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Annual Research Conference 2017Abstract Booklet
School of Electrical and Electronic Engineering
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Table of contents
ARC 2017 welcomes you………………………………………………………………..
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ARC 2017 Committee .................................................................................................. 4
Sponsor’s and Guest’s Information………………………………………………………
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Presentation schedule…………………………………………………………………….
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Poster schedule…………………………………………………………………………..
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Map of The Research Beehive…………………………………………………………...
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Oral Presentation Abstracts ………………………………….......................................
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Poster Presentation Abstracts ......................................................................................... 35
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ARC 2017 welcomes you
On behalf of the School of Electrical and Electronic Engineering, the ARC 2017 Committee
would like to offer a warm welcome to the 19th Annual Research conference (ARC 2017) at
Newcastle University.
In its first 13 iterations, ARC was known as Post Graduate Conference (PGC). In its early
beginning, it has been initiated as an in-house platform for students in order to practice their
communication skills and show off their research Then, it has been growing to become a well-
known platform for research networking and a bridge between academia and industrial partners,
within and beyond our University.
The School of Electrical and Electronic Engineering at Newcastle University aims to
provide a research environment in which ambitious new and original ideas can flourish and in
which every individual member of staff can be research active. The School was awarded a 5A for
research in the Research Assessment Exercise (RAE) 2001. Research has increased dramatically
since the RAE 2001 and we have exceeded our targets for the RAE 2008. In The Sunday Times
University Guide on Research Quality EEE is ranked amongst the top 5 schools in the UK. Our
research work is centred on four major research groups of international standing in
Communications, Sensors, Signal and Information Processing (ComS2IP), Electrical Power (EP),
Emerging Technologies and Materials (ETM) and Micro Systems (μSystems). The School runs an
Annual Research Conference which provides a showcase for our research students and young
research staff. This annual event is an excellent opportunity for staff and research students to come
together with industrial partners to celebrate the school’s research and collaborative links. It is a
great networking event, where attendees can meet people from other research areas, exchange
knowledge and discuss common research interests.
The conference organising committee is very pleased to welcome our industrial and
academic sponsors SIEMENS, ARUK, Wolfram, IET and IEEE and we look forward to their
participation throughout the conference three days. Contributions from our sponsors have allowed
the committee to bring more value and expertise to the conference and for that, we are very grateful.
This year will be the first ARC to have a tutorial session where three prestigious companies are
giving tutorials in different disciplines: NI, Wolfram, and COMSOL. Having such an opportunity is
one of biggest achievement of our committee where our school PGRs and researchers will make use
of the cutting-edge tools which will definitely help them in achieving their research projects and
boost their CVs.
This year’s conference will involve over 109 technical presentations describing the
University’s latest research and findings to over 160 attendees across the three days. This will cover
a vast range of research areas that are explored across every research group within the school. We
are very proud of the growing strength of researchers and their cutting edge work.
Finally, this year will have an awards ceremony of £100 given for best paper, poster and oral
presentation winner of each group and combined networking event at the Research Beehive, old
library. This will be followed by prize giving for best papers, presentations, and posters. The
networking event is aimed at encouraging cross-research-group networking as well as with the
industrial sponsors and representatives from the IET. We hope that you find the three days
interesting that you thoroughly enjoy these days of the Annual Research Conference 2017, and take
something of value and lasting memory.
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ARC 2017 Committee
Harith Al-Shwaily
Chair
Group: ComS2IP
Ruisheng Li
Vice Chair / Student Liaison
Group: EP
Ari Al-Jaf
Industrial Liaison
Group: EP
Mohammed Al-hayanni
Media Executive
Group: Micro System
Bilal Jebur
Event Coordinator / Secretary
Group: ComS2IP
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Sponsors and Guests Information
1. SIEMENS.
Siemens Energy Management Division is one of the leading global suppliers of products,
systems, solutions, and services for the economical, reliable, and intelligent transmission and
distribution of electrical power. As the trusted partner for the development and extension of
an efficient and reliable power infrastructure, Siemens offers utilities and the industry
the portfolio they need. This includes facilities and systems for the low voltage and
distribution power grid level, smart grid and energy automation solutions, power supply
for industrial plants, and high-voltage transmission systems.
More information available at: http://www.siemens.com/energy-management
2. WOLFRAM.
For three decades, Mathematica has defined the state of the art in technical computing and
provided the principal computation environment for millions of innovators, educators,
students, and others around the world. Widely admired for both its technical prowess and
elegant ease of use, Mathematica provides a single integrated, continually expanding system
that covers the breadth and depth of technical computing and with Mathematica Online, it is
now seamlessly available in the cloud through any web browser, as well as natively on all
modern desktop systems. More information available at: https://www.wolframalpha.com/
3. ARUK.
A leading supplier of Test & Measurement solutions since 1990, ARUK offers a comprehensive
range of products including ZES ZIMMER Power Analysers, ITECH Power Supplies, Teledyne
LeCroy Digital Storage Oscilloscopes and Associated Research Electrical Safety Tester. Based in
Milton Keynes, ARUL provides after sales support for the complete product portfolio.
More information available at: http://www.arukltd.co.uk/
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4. IET.
The Institution of Engineering and Technology (IET) is Europe’s leading publisher of world-class
engineering & technology content. We publish 32 research and letters journals; hundreds of
conference proceedings; over 450 eBooks; Inspec, the world’s leading database for physics and
engineering, and IET.tv, a vast online archive of video content.
More information available at: http://www.theiet.org/
5. Dr Themis Prodromakis
Themis is a Reader in Nanoelectronics and EPSRC Fellow affiliated with the
Nano Research Group and the Southampton Nanofabrication Centre of ECS
at University of Southampton. He is also a Honorary Research Fellow within
Imperial College London. He previously held a Corrigan Fellowship in
Nanoscale Technology and Science, funded by the Corrigan Foundation and
LSI Inc., within the Centre for Bio-inspired Technology at Imperial College
and a Lindemann Trust Visiting Fellowship in EECS UC Berkeley. Dr Prodromakis is a Senior
Member of the IEEE, and a Member of the INE and the IET, and also serves as member of the
BioCAS, Nanoelectronics and Gigascale Systems and the Sensory Systems Technical Committees of
the IEEE Circuits & Systems Society. He is also a member of the IEEE Nanotechnology Council,
representing the CAS society, and Associate Editor for Nature's Scientific Reports, IEEE Sensors and
the Frontiers in Neuromorphic Engineering. Dr Prodromakis is also the Director of the Lloyds
Register Foundation International Consortium for Nanotechnology, a global initiative for building a
safer world with nanotechnologies. His contributions on electron devices were recognised by his
appointment as a member of the Semiconductor Research Corporation (SRC) Emerging Research
Devices working group that produces the International Technology Roadmap for Semiconductors
(ITRS). In 2015, Dr Prodromakis established ArC Instruments Ltd, a start-up that delivers high-
performance testing infrastructure for automating characterisation of novel nanodevices. His
background is in Electron Devices and nanofabrication techniques, with his research being focused
on bio-inspired devices for advanced computing architectures and biomedical applications.
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TIME ARC 2017 Presentations Schedule – Day One, Research Beehive 25th
January 2017
08:30 - 09:00 Registration – Ground floor reception, Research Beehive.
09:00 - 09:15 Opening Plenary –Room 2.21 &2.22.
09:15- 09:35 Keynote Presentation - Room 2.21 & 2.22.
09:35 - 10:15 Coffee Break
SESSION I COMS2IP Presentation
Room 2.21
EP Presentation
Room 2.22
10:20 - 10:35 10:35 - 10:50 10:50 - 11:05 11:05 - 11:20 11:20 - 11:35
Chair: Charalampos Tsimenidis Assessor: Said Boussakta
PGR Yachao Ran PGR Yang Sun PGR Chaoqing Tang PGR Jiachen Yin PGR Israa Al-Shaikhli
10:20 - 10:35 10:35 - 10:50 10:50 - 11:05 11:05 - 11:20 11:20 - 11:35
Chair: Glynn Atkinson Assessor: Mohammed Elgendy
PGR Fangbo Liu PGR Xiang Li PGR He Liu PGR Yang Lu PGR Andrew Jenkins
11:35-12:50 Lunch Break
COMS2IP, µSystem and ETM Poster Session. Room 2.20.
SESSION II COMS2IP talks-Room 2.21 EP talks -Room 2.22
12:50 - 13:05 13:05 - 13:20 13:20 - 13:35 13:35 - 13:50 13:50 - 14:05 14:05- 14:20
Chair: Said Boussakta Assessor: Martin Johnston
PGR Yulong Chen PGR Zeyu Fu PGR Ali Munthr Alameer PGR Mahmoud Alageli PGR Huan Cao PGR Bilal Jebur
12:50 - 13:05 13:05 - 13:20 13:20 - 13:35 13:35 - 13:50 13:50 - 14:05 14:05- 14:20
Chair: Volker Pickert Assessor: Petros Missailidis
PGR Weichi Zhang PGR Chenming Zheng PGR Yaohui Gai PGR Huaxia Zhan PGR Yerasimos Yerasimou
- - - - - - - - - - - -
14:20 - 14:40 Tea Break
SESSION III COMS2IP talks -Room 2.21 µSystem talks -Room
2.22
14:40 - 14:55 14:55 - 15:10 15:10 - 15:25 15:25 - 15:40 15:40 - 15:55 15:55 - 16:10 16:10 – 16:25
Chair: Mohsen Naqvi Assessor: Jonathon Chambers
PGR Sinan Alkassar PGR Fahad Alsifiany PGR Ruslee Suthaweekul PGR Mohammed Dahri Buhari PGR Saadoon Al-Sumaidaee PGR Xiaotian Chen PGR Hayfaa Hussein
14:40 - 14:55 14:55 - 15:10 15:10 - 15:25 15:25 - 15:40 15:40 - 15:55 15:55 - 16:10 16:10 - 16:25
Chair: Graeme Chester Assessor: Alex Bystrov
PGR Lijuan Xia PGR Konstantinos Goustos PGR Mohammed Al-Hayanni PGR Kaiyuan Gao PGR Yuqing Xu PGR Issa Qiqieh PGR Mohammed Al-Daloo
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TIME ARC 2017 Presentations Schedule – Day Two, Research Beehive 26th January 2017
SESSION IV ETM talks -Room 2.21 EP talks -Room 2.22
09:00 - 09:15 09:15 - 09:30 09:30 - 09:45 09:45 - 10:00
Chair: Jonathan Goss Assessor: Noel Healy
PGR Johannes Gausden PGR Hind Alsnani PGR Luke Bradley PGR Faiz Bin Arith
09:00 - 09:15 09:15 - 09:30 09:30 - 09:45 09:45 - 10:00
Chair: Dave Atkinson Assessor: Simon Lambert
PGR Ari Akbar Al-Jaf
PGR Hamza Khalfalla PGR Ilias Saratakos PGR Stalin Eloy Munoz Vaca
10:00 - 10:20 Coffee Break
SESSION V COMS2IP talks -Room 2.21 EP talks -Room 2.22
10:20 - 10:35 10:35 - 10:50 10:50 - 11:05 11:05 - 11:20 11:20 - 11:35 11:35 - 11:50
Chair: Martin Johnston
Assessor: Gui Yun Tian
PGR Wael Abd Al Alaziz PGR Aobo Zhao PGR Zaid Abdullah PGR Jafaar Al-Khasaraji PGR Safaa Nash At-Awny
PGR Jamal Hussain
10:20 - 10:35 10:35 - 10:50 10:50 - 11:05 11:05 - 11:20 11:20 - 11:35 11:35 - 11:50
Chair: Nick Baker Assessor: Mohammed Dahidah
PGR Jamie Lamb PGR Mohamed Mohamed PGR Mohammad Raihan PGR Ruisheng Li PGR David Mecrow PGR Ehsan Dehghan-Azad
11:50-13:15
Lunch Break
EP Poster Session. Room 2.20.
A talk given by Dr Themis Prodromakis. Room 2.21.
SESSION VI COMS2IP talks -Room 2.21 ETM talks -Room 2.22
13:15 - 13:30 13:30 - 13:45 13:45 - 14:00 14:00 - 14:15 14:15 - 14:30
Chair: Mohsen Naqvi Assessor: Charalampos Tsimenidis
PGR Sameer Alsudany PGR Lindsay Smith PGR Ahmad Abdulfattah PGR Denis Ona
- - - - - - - - - - - - -
13:15 - 13:30 13:30 - 13:45 13:45 - 14:00 14:00 - 14:15 14:15 - 14:30
Chair: Mark Rayson Assessor: Patrick Briddon
PGR Nurul Mohamed PGR Tiago Marinheiro
PGR Sherko Ghaderi PGR Muhammed Idris
PGR Fatimah Bahrani
14:30 - 14:50 Tea Break
SESSION VII µSystem talks -Room 2.21
14:50 - 15:05 15:05 - 15:20 15:20 - 15:35 15:35 - 15:50 15:50 - 16:05 16:05 - 16:20
Chair: Patrick Degenaar Assessor: Fei Xia
PGR Vladimir Dubhikhin PGR Ali Majeed Aalsaud
PGR Mohamed Abulgalgha PGR Dave Burke PGR Jonathan Beaumont PGR Alessaxundro De-Gennaro
16:20 – 16:50 Drink Reception
16:50 – 17:40 Closing Plenary. Room 2.21 and 2.22.
Presentation Ceremony - Dr Glynn Atkinson, EEE Postgraduate Research Director
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TIME ARC 2017 Presentations Schedule – Day Three, Research Beehive
27th January 2017
SESSION I First Tutorial -Room 2.21
09:00 – 11:30
LabVIEW Tutorial
SESSION 2 Second Tutorial -Room 2.21
11:30 – 13:00 Mathematica Tutorial
SESSION 2 Third Tutorial -Room 2.21
14:00 – 17:00
COMSOL Tutorial
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ARC 2017 Poster Presentations Schedule – Day One, Research Beehive 25th January 2017 (09:00 – 17:00)
Board No. Group: ComS²IP 1 Adi Mahmud Jaya Marindra
2 Ana Carolina Pinto Da Silveira
3 Federico Angelini
4 Haicang Li
5 Monika Roopak
6 Scott Stainton
7 Yang Xian
Group: ETM
8 Amy Peters
9 Hector Galvan Brugal
10 James Beattie
11 Ryan James Siddall
12 Yu Tang
Group: uSystems
13 Adrian Reece Wheeldon
14 Banafsaj Jaafar
15 Danhui Li
16 Serhil Mileiko
17 Sidharth Maheshwari
18 Thanasin Bunnam
Group: Electrical Power
19 Ahmed Almoraya
20 Cuili Chen
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ARC 2017 Poster Presentations Schedule – Day Two, Research Beehive 26th January 2017 (09:00 – 17:00) Board No. Group: Electrical Power
1 Bassey Nyong-Bassey
2 Bethany Hoare
3 Chaudhry Jibran Javaid
4 Dan Wood
5 Gashtil Hamidreza
6 George Gkiza
7 Iago Martinez Ocano
8 Jin Xu
9 Jonathan Thompson
10 Li Lei
11 Luke Burl
12 Mark Turner
13 Najib Kabir Dankadai
14 Nasiru Aliyu
15 Nicola Chiodetta
16 Nikolas Spiliopoulos
17 Timothy D. Scott
18 Van-Binh Vu
19 Yarah Jamil Khawaja
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Maps of the Research Beehive
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Abstracts
Communications, Sensors, Signal & Information Processing
(ComS2IP) Research Group Presentations
Physical layer authentication scheme in WSN/IoT systems
Yachao Ran, Guiyun Tian and Martin Johnston
Conventional techniques of authentication involving cryptography and key management which are consuming for
computation and power resources applying to wireless devices. Physical layer authentication methods provide a
lightweight solution by utilizing physical layer. The paper investigates and analyses a design framework for
authentication at physical layer where authentication information is transmitted with data, using channel estimates and
one-way function. The efficiency of the scheme is tested through simulations for aspects of stealth and robustness. The
trade-offs in security, robustness and covertness is discussed.
Underdetermined Source Separation Using Time Frequency Masks and an Adaptive Combined Gaussian –
Student’s Probabilistic Model.
Yang Sun Waqas Rafique, Jonathon Chambers and Mohsen Naqvi
Time-frequency (T-F) masking algorithms are focused at separating multiple sound sources from binaural reverberant
speech mixtures. The statistical modelling of binaural cues i.e. interaural phase difference (IPD) and interaural level
difference (ILD) is a significant aspect of such algorithms. In this paper, a Gaussian-Student’s t distribution combined
mixture model is exploited for robust binaural speech separation. The weights of the distribution components are
calculated adaptively with the energy of the speech mixtures. The expectation maximization (EM) algorithm is applied
to calculate the parameters of the distributions. The speech signals from the TIMIT database are convolved with the real
binaural room impulse responses (BRIRs) from two datasets for the evaluation of the proposed method. The objective
performance measure signal to distortion ratio (SDR) confirms the improvement and robustness of the proposed
method.
Smart Compressed Sensing for On-line Evaluation of CFRP Structure Integrity
Chaoqing Tang , Gui Yun Tian, Said Boussakta and Martin Johnston
A compressed sensing (CS)-based algorithm framework is proposed enabling intelligent of open-ended waveguide
imaging system. Compared to traditional raster scan designs which require complete sampling, this smart compressed
sensing technique can generate whole damages pattern while the scanning is conducting, the sensor intelligence is
achieved by the proposed algorithm framework rather than seeking hardware update. The CS enables accumulated
down sampling and sparse recovery based on the spatial sparse and frequency sparse of impact damages on CFRP
structures. The damage edge/location in the reconstructed image can be detected using the proposed histogram
threshold edge detection (HTED) algorithm when the image is stabled enough. Edge-preserving smooth is used to
improve the stability of the reconstructed image. The experimental results illustrate time efficiency and more accurate
damage localization than other state-of-the art algorithm frameworks. The proposed smart compressed sensing
technique is attractive in quality control of CFRPs production.
Low cost Dual Polarised GPS antenna for effective signal acquisition in Multipath Environment
Jiachen Yin and Rajesh Tiwari
Recently, there has been increasing demands of precise positioning particularly in signal fading environment which is a
challenge for the autonomous and semi-autonomous vehicle. GPS signal is a right hand circularly polarisation (RHCP),
in very dense multipath environment, the polarisation may change to left hand circularly polarisation (LHCP). The GPS
receiver uses RHCP antenna. In vehicular communication, urban environment is a very good source of multipath which
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can lead GPS lose lock. In this paper, we design a low-cost dual polarisation patch antenna for a software-based GPS
receiver, which helps in acquiring LHCP signal
XG-FAST: Evolving the Copper Access
Israa Ali, Charalampos Tsimenidis and Martin Johnston
Recently, the fourth generation broadband technology (4GBB), abbreviated as G.fast, demon- strated data rate up to 1
Gbps over length loop up to 250 meters. XG-FAST dubbed fifth generation broadband technology is currently finalised
by ITU to succeed G.fast. This tech- nology aims to increase bit rate to 10 Gbps over shorten copper length loop up to
70 meters. This PhD project will focus on the concept of XG-FAST technology by utilising bonding and phantom
transmission modes over short loop lengths up to 30 meters and multiple copper twisted-pair cables. XG-FAST uses an
increased frequency range, up to 500 MHz with DMT modulation and concatenated Reed-Solomon (RS)code and four
dimensional trellis coded modulation(4-D TCM) for forward error correction with an interleaver in between. it is worth
noting that Soft-decision decoding of the TCM coding scheme is accomplished by using the Viterbi algorithm that its
output is represented the most likely transmitted sequence, which is the one at minimum Euclidean distance from the
received sequence.
Low Complexity Hybrid Precoding in Finite Dimensional Channel for Massive MIMO Systems
Yulong Chen, Said Boussakta, Charalampos Tsimenidis and Jonathon Chambers
Massive multiple input multiple output (MIMO) is an emerging technology for future wireless networks, scaling
up conventional MIMO to an unprecedented number of antennas at base stations. The large antenna array makes the
system achieve high channel capacity and spectral efficiency, but it also leads to the high cost of the hardware
complexity. In this paper, we consider a finite dimensional channel model in which finite distinct directions are applied
with M angular bins. In massive multi-user MIMO systems, a hybrid precoding method is proposed to reduce the
required number of radio frequency (RF) chains at the base station, employing single antenna per mobile station. The
proposed precoder is partitioned into a high-dimensional RF precoder and a low-dimensional baseband precoder. The
RF precoder is designed to obtain the power gain with phase-only control and the baseband precoder is designed to
facilitate multi-stream processing. For realistic scenarios, we consider the situation where the RF phase control is
quantized up to B bits of precision. Furthermore, an upper bound on spectral efficiency is derived with the proposed
precoding scheme. The simulation results show that hybrid precoding achieves desirable performance in terms of
spectral efficiency, which approaches the performance of zero-forcing precoding.
Robust Particle PHD Filter with Sparse Representation for Multi-Target Tracking
Zeyu Fu , Pengming Feng, Mohsen Naqvi and Jonathon Chambers
Recently, sparse representation has been widely used in computer vision and visual tracking applications, including face
recognition and object tracking. In this paper, we propose a novel robust multi-target tracking method by applying
sparse representation in a particle probability hypothesis density (PHD) filter framework. We employ the dictionary
learning method and principle component analysis (PCA) to train a static appearance model offline with sufficient
training data. This pre-trained dictionary contains both colour histogram and oriented gradient histogram (HOG)
features based on foreground target appearances. The tracker combines the pre-trained dictionary and sparse coding to
discriminate the tracked target from background clutter. The sparse coefficients solved by l1-minimization are
employed to generate the likelihood function values, which are further applied in the update step of the proposed
particle PHD filter. The proposed particle PHD filter is validated on two video sequences from publicly available
CAVIAR and PETS2009 datasets, and demonstrates improved tracking performance in comparison with the traditional
particle PHD filter.
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The Contribution of Peripheral and Central Vision on Cortex-like Models’ for Object Recognition
Ali Munthr Alameer, Kianoush Nazarpour and Patrick Degenaar
The human capability for recognition in a physical environment is still significantly better than any computer-based
model. It is believed that one reason for this, is that human utilises dierent visual fields for recognition depending on the
recognition task. Experiments on human subjects, done in [1], have shown that peripheral vision is more important than
central vision to achieve maximum performance in recognising a scene. In this paper, we present our visual cortex
model (En-HMAX) alongside with the HMAX model to replicate the experiments of [1]. We have created similar
experimental conditions using both “window” and “scotoma” conditions for object and scene datasets. Our experiments
show that the En-HMAX model achieves a maximum accuracy of 99% using only the peripheral vision (up to 7 visual
angle) for scene recognition. However, the experimental results have shown more sensitivity toward the information in
the centre when an object dataset has been used for recognition. Furthermore, the experiment on retinal images predicts
that central information is more ecient across all recognition tasks using same image area (in pixel), this is consistent
with the results in [1] . The inferred dierences in the relative important areas in cortex-like models had led us to train
and test only these regions of the input images. The results suggest that 50% of the visual field (relative data) is enough
to achieve a maximum accuracy of 95% to classify unseen images. This suggests that bio-inspired models, such as the
En-HMAX distribute a relative order of importance depending on the type of the processed data.
Relay Selection for Asynchronous AF Relay Networks with Frequency Selective Channels
Mahmoud Alageli , Aissa Ikhlef and Jonathon Chambers
In this paper, relay selection schemes in asynchronous multi-relay network for frequency selective channels have been
investigated. In particular, distributed Alamouti space time coding and amplify-and-forward (AF) relaying are
exploited, and orthogonal frequency division multiplexing (OFDM) is implemented with adaptive cyclic prefix (CP) to
deal with the frequency selectivity of the channels and timing errors. Several optimal and suboptimal relay selection and
joint relay-subcarrier selection schemes have been proposed based on two selection criteria. The first selection criterion
uses the end-to-end signal-to-noise ratio (SNR) and the second one uses the effective capacity which is a function of
both the end-to-end SNR and the CP length. Simulation results reveal that the optimal relay selection based on effective
capacity performs better in terms of network outage probability compared to the selection based on the SNR alone.
Also, it is shown that the more severe the frequency selectivity of the channels the larger the gain.
Performance of Polar codes on additive impullsive Noise Channels
Huan Cao and Martin Johnston
As an emerging class of error correction codes, polar codes are the first proven capacity-achieving codes for any
symmetric binary input discrete memoryless channels (BDMCs). They have a very low encoder and decoder
complexity and are now considered as an error-correcting code in wireless standards such as 5G. In most
communication systems, the noise at the channel is usually assumed to be Gaussian. However, this assumption is not
always valid if the signal is affected by impulsive noise. The aim of this paper is to evaluate the bit error rate
performance of polar codes with successive cancellation decoding on impulsive channels.
Performance Analysis of an AF Full-Duplex Physical-Layer Network Coding System
Bilal Jebur , Charalampos Tsimenidis, Martin Johnston and Jonathon Chambers
In this paper, we present a two-way relay channel (TWRC) network that utilizes a full-duplex physical layer network
coding (FD-PLNC) scheme in conjunction with amplify-and-forward (AF) relaying and orthogonal frequency-division
multiplexing (OFDM). In order to cope with the self-interference (SI) induced by the FD mode of operation, a self-
interference cancellation (SIC) scheme is utilized at each node in the proposed system. The performance of the
proposed system is thoroughly investigated in the presence of residual SI by deriving a closed-form expression for the
distribution of the tight upper bound end-to-end (E2E) signal to interference and noise ratio (SINR). Furthermore, an
exact closed-form expression for the tight upper bound ergodic capacity is derived and used to evaluate the E2E upper
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bound ergodic capacity of the proposed AF-FD-PLNC system. The obtained results demonstrate the ergodic capacity
gain of the proposed AF-FD-PLNC over the ergodic capacity of traditional AF half-duplex (HD) PLNC systems. In
particular, the proposed AF-FD-PLNC can increase the ergodic capacity of AF-HD-PLNC by a factor of 2 when the
SNR is higher than 25 dB and the SI to noise ratio is less than 0 dB.
Efficient Eye Corner and Gaze Detection for Sclera Recognition Under Relaxed Imaging Constraints
Sinan Alkassar, Lok Woo, Satnam Dlay and Jonathon Chambers
Sclera recognition has provoked research interest recently due to the distinctive properties of its blood vessels.
However, segmenting noisy sclera areas in eye images under relaxed imaging constraints, such as different gaze
directions, capturing on-the-move and at-a-distance, has not been extensively investigated. In our previous work, we
proposed a novel method for sclera segmentation under unconstrained image conditions with a drawback being that the
eye gaze direction is manually labeled for each image. Therefore, we propose a robust method for automatic eye corner
and gaze detection. The proposed method involves two levels of eye corners verification to minimize eye corner point
misclassification when noisy eye images are introduced. Moreover, gaze direction estimation is achieved through the
pixel properties of the sclera area. Experimental results in on-the-move and at-a-distance contexts with multiple eye
gaze directions using the UBIRIS.v2 database show a significant improvement in terms of accuracy and gaze detection
rates.
Exploiting Differential Modulation in Multiuser-MIMO Systems with Downlink Precoding
Fahad Alsifiany , Aissa Ikhlefy and Jonathon Chambers
In this paper, we consider a space time block coded multiuser multiple-input multiple-output (MU-MIMO) system with
downlink precoding. In particular, we propose to use downlink precoding combined with differential modulation (DM)
to shift the complexity from the receivers to the transmitter. As a space time block code, we use the Alamouti code
which can be encoded/decoded using DM thereby eliminating the need for channel knowledge at the receiver. The
block diagonalization (BD) precoding method is used to cancel the co-channel interference (CCI) in addition to its
advantage of enhancing diversity and improving the bit error rate (BER). The proposed scheme allows reduction in the
receiver complexity as well as enhancing the performance of the system. Monte Carlo simulation results demonstrate
the effectiveness of the proposed scheme.
Influence of Lift-off on Microwave Open-ended Waveguide Time of Flight Based Tire Inspection
Ruslee Sutthaweekul , Guiyun Tian and Mohammed Buhari
The comfort and safety of driving vehicles largely depends on state of the tires. However, inspecting defects within tires
is a challenging task. Numerous inspection methods have been proposed such as X-ray, impact-acoustic and machine
vision. X-ray is a mature method providing high-resolution images of tire structure but it is costly and requires safety
precaution. Impact- acoustic requires impactor and cannot tolerate noisy environments; machine vision is
computationally slow and can only obtain information of the tire surface. In this paper, we propose the use of
Microwave inspection using open-ended waveguide probe that is fast, low cost and can penetrate to reveal the internal
structure of the tire. This is achieved using Time of Flight (ToF) to extract the tire features for the reconstruction.
Cumulative side lobe level is used to determine the optimum lift- off scanning range which is used for the tire scanning.
Experimental results show that the technique can image the surface and reveal the internal structure of the tire.
SAR Multiple Targets Reconstruction using MUSIC-LSE Algorithm
Mohammed Dahri Buhari, Ruslee Sutthaweekul and Guiyun Tian
In Synthetic Aperture Radar (SAR) image reconstruction, the quality of the image depends on the range and cross range
resolution to resolve multiple target positions. If the distance between the targets is less than both SAR resolutions, the
radar imaged them as one single target. To overcome this challenge, Orthogonal Frequency Division Multiplexing
(OFDM)
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SAR has been proposed to improve the image resolution. However, the image quality degrades in lower boundary
conditions. In this paper, we propose the use of Multiple Signal Classification (MUSIC) algorithm to estimate the signal
Direction of Arrival (DoA) and Least Square Estimation (LSE) algorithm to estimate the phase history. The Cross-range
Profile Reconstruction (CPR) is reconstructed using the phase history and combined with Range Profile Reconstruction
(RPR) to form the image. Simulation results show that the proposed MUSIC-LSE SAR approach gives a higher image
resolution compared to the LSESAR imaging. The approach also shows that by estimating the signal DoA and then
apply LSE, the radar can separate the targets even at distances below the range and cross-range resolution without
necessarily increasing the bandwidth.
Recognizing The Facial Expressions using The Histogram Features of The LGGC-HD Descriptor and SVM
Classifier
Saadoon Al-Sumaidaee
We propose a new method for the facial expression recognition by constructing a new layer structure that compound
from the local gradient features based on the Gabor’s coefficients. Hence, we combine the Local Gradient Code-
Horizontal Diagonal (LGC-HD) descriptor with set of the Kernel Gabor Filters (KGFs). Firstly, we extract the Gabor
Features Map (GFM) by convolving each image with five scales and eight orientations of the KGFs. Then, we apply the
LGC-HD descriptor on the output of each image in the GFM to obtain the new Local Gabor Gradient Code-Horizontal
Diagonal descriptor (LGGC-HD). Consequently, a sequence of the histogram features of the LGGC-HD descriptor is
calculated from the 42 blocks of each image in the GFM. In terms of high feature dimensionality, we applied principal
component analysis as a reduction techniques. We then classified each expression based on the histogram features of
the LGGC-HD descriptor using two well-known machine learning methods, template matching and support vector
machine. The experimental results on the JAFEE database demonstrated the efficiency of the proposed method
compared to different methods in the state-of-the-art.
Active 3D Surface Temperature Mapping for Eddy Current Pulsed Thermography
Xiaotian Chen and Guiyun Tian
Eddy Current Pulsed Thermography is a Non-Destructive Testing and Evaluation technique which provides accurate,
quick and non-contact method for detection and identification of defects. Previous ECPT system heat the testing object
and use thermal camera to capture the transient state of the object for defect detection. However, thermal imaging
system is blurred and lack the information of geometry and depth. Furthermore, camera at different viewing angle will
have different imaging result due to optical projection as well as directional emissivity. To solve the problem, this paper
propose to use RGB-D camera to capture 3D point cloud. The 3D point cloud and thermal image is used to regenerate
3D thermal surface. A new registration method is proposed to establish reliable projection matrix. The fusion result has
shown that 3D active thermography gives a more accurate and better presentation of thermal distribution.
Study of Sparsity-Based Facial Expression Recognition on a Spontaneous Database
Hayfaa Hussein , Jonathon Chambers and Mohsen Naqvi
The target of facial expression recognition is to analyse a specific image or a set of video frames to detect an
individual’s emotion, thereby producing more natural and smarter interaction between human beings and computers. In
this paper, we investigate the identity-independent expression recognition problem. Our experimental results using a
Sparse Representation Classifier (SRC) together with Principal Component Analysis (PCA) and Fisher Linear
Discriminant Analysis (FLDA) methods on two types of databases namely the posed database CK+ and the spontaneous
database VDMFP, yield two main findings: results with the spontaneous database are worse than with the posed
database in terms of average accuracy. Training on difference images rather than the original images yields better
accuracy both with the posed and spontaneous databases.
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Non-Binary Turbo Codes on Additive Impulsive Noise Channels
Wael Abd Al Alaziz, Martin Johnston and Stephane Y. Le Goff
It is well known that binary error-correcting codes with iterative decoders can achieve near Shannon-limit performance
on the additive white Gaussian noise (AWGN) channel, but their performance on more realistic wireless channels can
become degraded due to the presence of burst errors or impulsive noise due to interference. A better performing coding
scheme is the class of non-binary codes, which are known to be more effective in correcting burst errors, but there is no
research reported in the literature investigating non-binary codes on impulsive noise channels. In this paper, we
investigate the performance of no binary turbo codes defined in finite fields on symmetric alpha stable impulsive noise
channels and compare with comparable binary turbo codes employing a Cauchy receiver to mitigate the effects of the
channel. Our simulation results show that the no binary turbo code slightly better than the binary turbo code on the
AWGN channel, but significantly outperforms the binary turbo code as impulsiveness increases.
UHF RFID Tag Antenna Based Sensors for Corrosion Characterization with Miniaturization for Resolution
Enhancement
Aobo Zhao and Guiyun Tian
Two Ultra-High Frequency (UHF) Radio-Frequency Identification (RFID) tag antenna based sensor designs for steel
corrosion sensing and miniaturization for robustness improvement are proposed in this paper. In early corrosion process
of steel, the corrosion layer thickness increases. To characterize corrosion, the new antenna adopts the structure of patch
antenna with a meander line feed. Based on the microstrip line theory, the impedance of meander line feed changes as
the corrosion layer thickness increases. The impedance changes of meander line feed results in mismatch between tag
antenna and tag IC so that this change can be captured with characteristics change of the tag antenna. To increase the
spatial resolution, 3D antenna via folding has been redesigned from the non-folded antenna to reduce the antenna size.
Experimental studies with ThingMagic development kit on dedicated corrosion samples have been undertaken to
validate the antenna designs. Resonance frequency features of developed antenna are studied for corrosion
characterization. Folded antenna shows enhanced robustness while non-folded antenna has better thickness sensitivity
with averaged effect. The experimental study has validated the different antennas for RFID-based corrosion
characterization.
Tabu Search vs. Bio-inspired Algorithms for Antenna Selection in Spatially Correlated Massive MIMO Uplink
Channels
Zaid Abdullah, Charalampos Tsimenidis and Martin Johnston
Massive Multiple Input Multiple Output (MIMO) systems can significantly improve the system performance and
capacity by using a large number of antenna elements at the base station (BS). To reduce the system complexity and
hardware cost, low complexity antenna selection techniques can be used to choose the best antenna subset while
keeping the system performance at a certain required level. In this paper, Tabu Search (TS) and three bio-inspired
optimization algorithms were used for antenna selection in Massive MIMO systems. The three bio-inspired algorithms
were: Particle Swarm Optimization (PSO), Genetic Algorithm (GA), and Artificial Bee Colony (ABC). Simulations
showed promising results for the TS by achieving higher capacity with GA than PSO and ABC, and much shorter CPU
time than any of the bio-inspired techniques.
Channel Modelling For Underwater Optical Wireless Communication Based On Monte-Carlo Simulation
Jafaar Al-Khasaraji and Charalampos Tsimenidis
Channel Modelling For Underwater Optical Wireless Communication Based On Monte-Carlo Simulation. This paper
considers the point-to-point configuration links for underwater optical wireless communication (UWOC). The
commonly used Monte Carlo method is employed to build the impulse response of UWOC channels for three aqueous
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environments. We then existing a double Gamma functions (DGF) model to characterize under water optical impulse
response. Simulation results have shown that the DGF model agrees with the Monte Carlo simulations for various FOV
and water types.
BER Computation of Hierarchical Modulation with OFDM-PLNC in Fading Environments
Safaa Nash At-Awny and Charalampos Tsimenidis
In this paper, we investigate the performance of hierarchical modulation (HM) that utilizes a half-duplex physical layer
network coding (HD-PLNC) scheme with two-way relay network (TWRN) and denoise and forward (DNF) operations
over Rayleigh Fading channel. The proposed scheme is based on analyzing the average bit error rate (BER) expression
of the 4/16-QAM HM of the information exchanged between the two end nodes, A and B, with the aid of a relay. The
main concept is to merge two different streams at the modulation level, the High Priority (HP) stream and the Low
Priority (LP) stream, which select the quadrant and the position inside the quadrant, respectively. Furthermore, a half-
duplex physical layer network coding (HD-PLNC) scheme and orthogonal frequency-division multiplexing (OFDM)
system are used to remedy the two-way relay network (TWRN), which is helping the two end nodes to communicate.
This scheme improves the system throughput by deriving the bit error rate performance (BER) expressions of the 4/16-
QAM constellations over Rayleigh fading channel and describing the point-to-point performance. In this
correspondence, particular numerical results show that the BER expressions and the simulation results are closest
matches over Rayleigh fading environments depending on the constellation size M.
Exact Outage Performance of the SIMO Cognitive Cooperative Network in the Presence of Co-Channel
Interference
Jamal Hussein
The nature of cognitive radio is based on the coexistence of secondary users in the area of primary users. Co-channel
interference (CCI), therefore, is a vulnerable phenomenon in such a system. Motivated by this, a more practical scenario
has been considered for studying the performance of the single-input-multiple-output (SIMO) underlay cognitive
cooperative network. In this investigation, the primary transceiver is considered as well as the impact of the CCI on the
secondary network. For this practical scenario, the equivalent signal-to-interference-plus-noise ratio (SINR) of the
secondary system is obtained by employing the selection combining (SC) technique at the receiver side. Then, the
cumulative distribution function (CDF) of the equivalent SINR is derived. Using the derived CDF, exact outage
probability for the secondary network is assessed. From the results, it can be deduced that using a multi-antenna scheme
and applying the SC technique has the advantage of improving the system performance. Moreover, besides the impact
of the interference power constraint, the presence of the primary transmitter and the CCI will severely reduce the system
performance, especially when the CCI linearly increases with the secondary transmit powers. Finally, numerical results
and Monte Carlo simulations have also been provided to support the correctness of the analytical derivations.
A Novel Algorithm to Compress IPV6 Header using Context-Based Scheme for 6LoWPAN Networks
Sameer Alsudany Said Boussakta and Martin Johnston
Internet Wireless embedded devices are a subset of the Internet of Things. The connections between wireless sensor
networks (WSNs) and the Internet is challenging due to the large differences in the capabilities
of the two technologies. One of the most important challenges is the difference in the Maximum Transmission Unit
(MTU). The frame length of the medium access layer of the WSN is not large enough to embrace the IPV6 header
efficiently. Therefore the IETF (Internet Engineering Task Force) has developed the encoding format LoWPAN_IPHC
to map and compress the multi-byte IPV6 header to 4-bits CID (context identifier). The CID can map only 15 prefixes,
which is far too few for practical needs. Therefore, this paper proposes a novel algorithm to manage the context system
by using an adaptable scheme with two modes. One mode conforms to the requirements of the standard scheme. The
other mode uses 8-bits CID to map and compress up to 255 Internet prefixes. The system adapts its operation according
to the most energy saving mode. The scheme implements four processes (mapping, updating, synchronization, and
adaptation) to manage the context system. Simulation results prove the performance of the proposed algorithm which
outperforms the standard scheme that uses only 4-bits CID.
21
Acoustic Emission Methods to Localise Partial Discharge Events in Subsea Umbilicals
Lindsay Smith and Jiff Neasham
Failures in Umbilicals caused by insulation breakdown from partial discharge (PD) in MV cables can lead to excessive
down time and costs. Ideally these discharges would be detected & located before complete breakdown occurred. This
paper discusses acoustic emission sensing methods used to detect PD events along with time difference of arrival
(TDOA) and time delay estimation (TDE) algorithms to establish the fault location. Analysis is shown on the two main
propagation paths for the emission from the PD signal. The first being the propagation through the cable itself and the
second being the propagation out of the umbilical and through the surrounding water. The analysis is performed on
results taken from trials carried out on cable samples containing 'man made' faults which are subjected to HVAC to
create PD events.
Subthreshold-based m-sequence code generator for ultra low-power body sensor nodes
Ahmad Abdulfattah, Charalampos Tsimenidis and Alex Yakovlev
Power dissipation is one of the challenges of body sensor nodes (BSNs) transceivers in which ultra-low power
consumption is essential for the sensor QoS. In this paper, m-sequence code generator designs for different code lengths
are presented and analyzed to demonstrate their efficiency within the region of sub-threshold voltage. The proposed m-
sequence generators are investigated at a transistor level and their quality and reliability are verified using the auto-
correlation and eye diagram characterizations. The maximum switching frequency is obtained at different supply
voltages and the power consumption is measured at the maximum achieved frequencies. Simulation and results reveal
the capability of our design schemes to work efficiently within the region of sub-threshold voltage.
Improving detectability of Pulsed Eddy Current Sensor for Pipeline Integrity Inspection
Denis Ona and Gui Tian
Detection sensitivity of PEC largely depends on crack length orientation with respect to eddy current (EC) flow
direction in test specimen. In traditional EC testing the induced eddy currents flow mainly through a single direction in
the tested specimen. In pipeline, axial, circumferential and angular cracks are common and one specific orientation of
EC flow will not detect all of the cracks. This paper investigates the use of printed circuit board (PCB) PEC sensors
with different orientations and configurations for detection of cracks at different orientations. A rectangular steel slab
with fabricated cracks is scanned using PCB based PEC sensors with two different coil configurations at various scan
orientations. Results show that for angular positioning of the sensor (45 degrees), the lowest point determined the crack
position however for perpendicular position the highest range determined the crack position. This shows that the sensor
orientation has influence on the crack detection sensitivity
Electrical Power (EP) Research Group Presentations
A Triple Three-phase Fault Tolerant Induction Machine
Fangbo Liu and Barrie Mecrow
A tipple three-phase induction machine rewound from a conventional three-phase induction machine has been proposed
and invested for safety critical applications. In order to achieve the optimized fault-tolerant capability, three sets of the
three-phase winding is adopted and to make that there is no overlapping between each two parts the segregated winding
configuration is devised here. Each set of the three-phase segment is supplied by a conventional three-phase inverter.
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With the “off-the-shelf” inverter, the cost reduced and integration speed increased. The performance of the triple three-
phase induction under one segment failure and two segments failure has been simulated by the FEA software, according
to those results some other parameters is calculated . The results show that the triple three-phase induction machine
exhibits high performance and good capability of the fault tolerant.
Signal injection Method for SiC MOSFET Health Monitoring
Xiang Lu
Comparative works have been done in regarding the TSEPs (Temperature Sensitive Electrical Parameters) of both Si
devices including MOSFET and IGBT and SiC MOSFET. The results show that traditional TSEPs which work well for
the Si devices are not quite suitable for the SiC MOSET. This is mainly because the sensitivity of the TSEP of SiC
MOSFET is too small to be detected in practical experiment and the shift of the TSEP is not sufficient enough to tell the
temperature change. Another difficulty is the dynamic response of the SiC MOSFET is also hard to be observed due to
the ultra-fast switching frequency while the device is more vulnerable and sensitive to the parasitic components than the
Si devices. In this letter, a new method has been proposed to use signal injection to detect the degradation of the bond
wire of SiC MOSFET.
High Voltage High Power Modular Multilevel DC/DC Converter for Off-shore Windfarm DC Collection Point
He Liu
This paper presents a new high voltage high power DC/DC converter configuration suitable for off-shore windfarm
application. The proposed converter functions as a DC collection point and boosts the wind generators voltage to
facilitate the employment of high voltage direct current (HVDC) transmission lines. The proposed converter utilizes the
modular multilevel converter (MMC) structure and combined converter linked by medium frequency transformer,
which leads to lower voltage and current stresses of diode bridge rectifier compared to the conventional DC/DC
converters while using relatively smaller transformer. This topology also features modularity, which significantly
improves system’s reliability and implementation. This paper presents the design and analysis of the proposed converter
under various operating conditions. A new control method will be derived and demonstrated to show the effectiveness
of the proposed system.
Double Stator Switched Reluctance Machine with four phase opposing winding
Yang Lu and James Widmer
The switched reluctance machine (SRM) is a promising candidate for no permanent magnet electric propulsion system.
However, the lower torque density and efficiency compare to other electrical machines such as permanent magnet
synchronise machine (PMSM), may become one of the main drawback. To achieve a higher performance than a
conventional SRM, this paper will describe a SRM with double stator structure and four phase opposing winding
configuration. It can be proved that the four phase opposing winding configuration may provide best torque producing
ability during phase interaction period (if the winding are excited by 180-degree ideal square wave). And this
superiority could become more distinct with high split ratio and deep magnetic saturation level. The double stator
structure can be exactly pleased by the same design trend, and itself is a promising novel SRM structure as well. The
combination of these two ideas will be simulated using 2D FEM method and will present an excellent torque per unit
copper loss value. The manufacture and assemble method will be briefly discussed as well. The plastic material will
support and stable the rotor lamination to minimum the potential eddy current in rotor. And the structure is examined by
3D FEM in JMAG to prove its survivability under centrifugal force.
Improving the Scheduling of Services that Energy Storage Systems could provide in Urban
Andrew Jenkins, Charalampos Patsios, Phil Taylor, Neal Wade, Phil Blythe and Olamayowa Olabisi
Energy Storage Systems (ESSs) and microgrids can enable the connection of Electric Vehicles (EVs) and Solar
generation to urban electrical networks, by ensuring power flows and voltages stay within equipment ratings, without
23
network reinforcement. The load from EVs and generation from Solar is often uncertain and as such the scheduling of
the ESS to keep the network operating state within equipment ratings must take this into account, while also minimizing
the storage power and energy exchange to do this in a cost effective manner. This paper uses a Robust Optimisation
(RO) formulation, utilizing a linearization of the full AC power flow calculation, to schedule ESS under load and
generation uncertainty. A contribution is made through considering the optimisation horizon to be considered during the
optimisation. By minimizing the horizon, the time step between each rolling re-scheduling of the ESS can be minimized
thus leading to more frequent updated forecasts and reduced uncertainty. This in turn is expected to lead to reduced ESS
degradation and losses from round trip efficiencies.
DC Current Extraction in Transformer-less Inverter Based on DC Link Sensing Technique
Weichi Zhang, Matthew Armstrong and Mohammed Elegendy
Transformer-less, grid connected, photovoltaic inverter systems are becoming increasingly popular due to their reduced
volume and high efficiency performance. However, the potential risk of dc current injection into the grid is of
significant concern in such systems, and strict guidelines and standards are normally in place to protect the integrity of
the distribution network. Nevertheless, accurate determination of the dc current content in the inverter output is
particularly challenging. This is primarily because the very small dc signals have to be extracted from much larger ac
signals, and the measurements can be significantly influenced by noise. This paper investigate a novel dc extraction
method based on the dc link sensing technique. The principle of the proposed circuit and algorithm are thoroughly
explained and the advantages in simplicity, accuracy and robust are successfully demonstrated in theory and simulation.
Condition Monitoring of Capacitors in Modular Multilevel Converters
Chenming Zhang and Mohamed Dahidah
This paper address the condition monitoring of sub-module (SM) capacitors in modular multilevel converter (MMC),
by utilising the online estimation methods to get capacitance and ESR as indicators to reveal the conditions of the sub-
module capacitors. The online estimation scheme require the transfer function derived from second order differential
equations which only works during the on-state of SM. The input and output of transfer function are obtained by using
the existing arm current sensors and capacitor voltage sensors. The proposed scheme is to get sufficient sampling points
from ON-STATE period for the stochastic-gradient algorithms based on the existing sorting balancing control method.
Therefore no extra signal injection or terminating the system operation are required. The accuracy test is based on
MATLAB/Simulation environment and experiment results are presented to validate the proposed estimation scheme.
24
Cooling System Investigation and Analysis for Electrical Machines - A Review
Yaohui Gai, Mohammad Kimiabeigi and James Widmer
This paper presents an overview of the studies and analysis of cooling system for electrical machines. A high
temperature has an insignificant effect on the machines performance and life expectancy. Accurate and promptly heat
dissipation is an essential element of the machine design process. The various cooling methods: natural cooling, air and
liquid forced convection, phase change are proposed and compared the merits and defects of each. In addition, some of
practical applications are described. Finally, the thermal and mechanical behavior are taken into account based on
lumped parameter thermal-network, finite-element analysis and computational fluid dynamics.
A Cascaded Transformer-based Equalization Converter for Series Connected Battery Cells
Huaxia Zhan
Lithium-ion batteries have been used as energy storage device in many applications, such as electric vehicles. As part of
the battery management system a process for voltage equalisation of cells throughout the stack is essential. The
drawback of traditional transformer-based equalization circuit is the size and the difficult manufacture of the
transformer.
This paper proposes a new battery charging system integrated with equalization circuit. Compared to traditional
equalization circuit, the new circuit assembles charging and equalization function. Therefore, it will reduce the volume
and fabrication cost of the system. The topology concept and operating principals are discussed in this paper. In
addition some experimental work has been displayed as well.
A Liquid Metal Cooling Device for Adaptive Thermal Management of IGBT Power Modules
Yerasimos Yerasimou and Volker Pickert
Power semiconductors are key elements for safety critical and high-reliability applications. While operating, high
junction temperature swings occur that result in high thermomechanical stress within the structure of the power module.
Consequently, the lifetime of the module can be significantly reduced. Liquid metals received little attention in the area
of power semiconductors cooling, despite being able to remove high heat fluxes. This paper proposes a novel adaptive
liquid metal cooling device, which is capable of reducing the thermomechanical stress of the power semiconductors by
adapting the flow rate of the coolant. A magneto hydrodynamics pump is utilised for driving the liquid metal, which is
impinged directly on the baseplate and under the IGBT chip. Experimental work has been carried out, clearly showing
the advantages that adaptive cooling can offer compared to a conventional heat sink.
Winding Arrangement and Design Development for Fault Tolerant EPS Systems
Ari Al-Jaf , Barrie Mecrow and David Moule
Driverless cars are expected to become a reality over the next 20 years. The sub-systems within these vehicles will
require increased fault tolerance and capability. This is in addition to the already high reliability, efficiency and
performance of today’s systems such as electric power steering (EPS) systems. This paper presents a motor design
development of such an auxiliary system. Predicted performance of various double-layer and single-layer options are
presented and contrasted.
An Adaptive Proportional Resonant Controller for Single Phase PV Grid Connected Inverter Based on Band-
Pass Filter Technique
Hamza Khalfalla, Salaheldine Ethni, Maher Al-Greer, Volker Pickert, Matthew Armostrong and Van Tung
Phan
This paper presents an adaptive proportional resonant (PR) controller for single phase grid connected inverter that
adapts its control parameters to grid impedance variations. Forth order band bass filter is designed and then integrated
with the adaptive scheme for on-line detection of any variations in the resonance frequency. The estimated frequency is
25
then processed by statistical signal processing operation to identify the variations in the grid impedance. For the on–line
tuning of the PR parameters, a look-up table technique is utilized and its parameters are linked with the estimated
impedance values. Simulation results based on MATLAB environment clearly verify the effectiveness of the proposed
control scheme for 2 kW grid connected inverter system.
Incorporating Asset Management into Power System Operations
Ilias Sarantakos , Simon Blake and Phil Taylor
Generally, decisions regarding power system operations are based only on operational parameters of the distribution
network (DN) such as voltages, currents and power flows. Asset condition is a key parameter that is usually not
considered by Network Management Systems (NMS) in their optimization process. Against this background, this paper
seeks to indicate that the condition of power system assets can influence the network operation decisions. The criteria
used to decide the optimal network operation are asset condition-based risk and
losses. This is illustrated by a case study, where a number of network reconfigurations are examined in a representative
DN and the results show that by taking asset condition information into account, then an improved operation of the
network can be achieved.
Frequency Response Enhancement of Wind Farms by using Hybrid Energy Storage Systems
Stalin Munoz Vaca, Charalampos Patsios and Phil Taylor
Several grid regulations require the provision of mandatory frequency response for large-scale grid wind generators.
This could affect their regular operation by limiting the generator’s energy and power capacity and triggering revenue
losses. The use of energy storage (ES) technologies can support in limiting these losses and guaranteeing the delivery of
mandatory services. Nevertheless, single energy storage devices might not be economically viable in many occasions.
The present paper addresses a techno-economic methodology for sizing hybrid energy storage systems (HESSs) when
working together with wind generators for the provision of frequency support. HESS refers to the combination of
multiple energy storage technologies and it merges the individual benefits of these devices without having their
drawbacks. The methodology applies linear programming for achieving the best combination of HESS and wind
generator’s reserves in terms of power and energy capacity and maximum revenues. This study was analysed in a 60
MW wind farm which contains Vanadium Redox flow batteries (VRFB) and supercapacitors under the United Kingdom
(UK) regulations and UK energy market. The results show that HESSs can provide higher economic benefits under
certain conditions in comparison with a single ES technology and with non-using ESS for this type of service.
Sensor-less Induction Motor Drive with Multilevel Converter, Output Filtering and Active Damping
Jamie Lamb
Passive power filters are required to have low losses. A high Q factor for a LC power filter is desirable. A high Q factor
is characteristic of a highly resonant underdamped system. Passive damping can be used to overcome the issues that this
presents however power is dissipated in the components used which significantly contributes to the total energy loss of
a power electronics system. Vector control with output filter is not a common practice. Inclusion of a highly resonant
filter to the system complicates the control scheme. PI controllers are a common component in most vector control
schemes. A PI controller transfer function interacts with the system and shifts the resonant frequency upwards, towards
the inverters switching frequency. This results in steady state oscillations in the machines terminal voltage limiting the
range of the PI-controller gains. This increases the system response times. Stator voltage knowledge is an essential
parameter for MRAS speed estimation and direct measurement is not normally possible with a PWM voltage source due
to the necessary high sampling rate. With inverter output filtering direct measurement of the machine terminal voltage
becomes possible.
Active damping can be utilised to defend against system oscillations and allow higher PI controller gains in order to
decrease response times. This ultimately improves the torque response of the system.
26
Challenges of Integrating Magnetics of LCL Filter into High Speed Machince with Pre-compressed coils
Mohamed Mohamed , Barrie Mecrow, Simon Lambert, David Atkinson and A. C. Smith
This paper presents a high speed high power machine with integrated magnetics of the grid side LCL filter. This
integrated drive has been designed to take full advantage of sharing the magnetic steel for volume reduction. The main
outcome of this paper is firstly the integration of all 3-phase LCL filter inductors into the proposed machine by sharing
the original machine’s magnetic circuit without magnetic cross-coupling whether between the integrated filter inductors
windings or with the main machine magnetic circuit. Secondly, the coils are prepressed directly to the double slot
machine to form a solid component with fill factors for the main machine and filter windings 60% and 50%
respectively. The use of a segmented stator enabled rapid and repeatable construction of this complex magnetic
component. There are a number of important design features which are not possible with conventional preformed Litz
windings for the main machine coils. For example, the main machine coils were formed with safety margin from the
machine slot opening along with the restriction of slot area. The prototype offers superior performance of the
achievement of filter inductances.
A novel Linear Permanent Magnet Vernier Hybrid Machine (LPMVHM) machine for ocean wave enrgy
converter and improved performance
Mohammad Abdul Hakim Raihan , Nick Baker and Kristopher Smith
In this paper, a linear permanent magnet vernier hybrid machine (LPMVHM) is proposed, in which the long mover
comprises of an iron teethed salient structure while, both magnets and armature windings are set on the stator.
Henceforth, it is reasonable for long-stroke applications, for example, wave energy power take-off. It took into account
a baseline model, analyses and compare the model with a novel proposed machine incorporates two different
polarization magnets together, which can reduce dominant leakage flux and improve flux density of the baseline model.
The proposed design has the benefit of having lower magnet mass, rigid and compact stator design with higher force
density, lower force ripple and back EMF compared to the initial model, while maintaining lower cogging force.
On-line Parameter Estimation of Non-Minimum Phase DC-DC Converters
Ruisheng Li and Matthew Armstrong
Time varying parameters, such of passive components within the circuit and load elements, can significantly impact on
the control and voltage regulation of power electronic systems, such as switch mode power converters (SMPC).
Therefore, there is increasing interest in parametric system identification and adaptive control techniques to optimize
system performance. Most literature focuses on the DC-DC buck converter. However, unlike the DC-DC buck
converter, the boost converter has two left half-plane poles (LHP) and one right half-plane (RHP) zero in its
mathematical model. The existence of a RHP zero in the s-domain transfer function causes a zero to be outside of the
unit cycle in the discrete model. As a result, system identification of the boost converter is much more difficult in
comparison to the buck converter. The paper sets out to illustrate the RHP zero problem in detail and propose a novel
method to resolve this problem.
Magnetic Field and Force Calculation Using 3D Analytical Methods
David Mecrow and Glynn Atkinson
A novel permanent magnet simulation was produced using the Coulombian model for permanent magnets. The
simulation calculates both the field from a primary permanent magnet and the resultant force on a secondary ring
magnet. The solver is compatible with any prismatic design, including rings and segment, and can be adapted to
irregular shapes.
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Sensorless control of IM based on stator-voltage MRAS for Limp-home EV applications
Ehsan Dehghan-Azad, Shady Gadoue and Dave Atkinson
This paper proposes a novel sensorless speed estimation for an induction motor (IM) based on a new stator voltage
model reference adaptive system (Vs-MRAS) scheme. This is utilized for torque-controlled drive (TCD) in limp-home
mode operation of EV applications. The Vs-MRAS scheme uses the error between the reference and estimated stator
voltage vectors and estimates the synchronous speed. Unlike existing MRAS schemes, the proposed sensorless scheme
does not require the measured nominal values of stator resistance, stator inductance, and rotor resistance. This scheme is
insensitive to variations of the aforementioned parameters. Moreover, using the proposed scheme eliminates the need
for slip calculation. The proposed scheme is implemented and experimentally tested in a lab environment, on a 19-kW
IM, and also applied on an electric golf buggy, powered by a 5-kW IM. The experimental results show that the
proposed scheme is immune to parameter variations and is consistent in vehicle-starting from standstill and hill-starting
tests. This scheme is also free from drift problems associated with a pure integration and is stable in the field weakening
region. The test-drive results from the golf buggy confirm suitability of the proposed Vs-MRAS scheme over a wide
range of speeds for the purpose of TCD in EV applications.
μSystems Research Group Presentations
A flash-FPGA based implantable neuroprosthetic micro-system for intervening epileptic seizures by optogenetics
Lijuan Xia and Mike Walker
Recent technological advances have shed lights on lightweight battery head-mounted operated microsystem for freely
moving transgenic rodents. In this paper, we demonstrate a flash-based FPGA micro-system in-vivo implantable in
freely moving transgenic rodents for intervening epileptic–like seizure in brain cells. The proposed neuroprosthetic
micro-system, which collects electrophysiological recordings of Local Field Potential (LFP), performing non-linear
proportional, integral and derivative processing and delivering close- loop pulse width modulation (PWM) optical
stimulus simultaneously, is composed of totally commercial off-the-shelf component. This implantable micro-system
can receive recording LFP from CANDO optrode , then amplify and digitalize the recording LFP to be used in digital
domain for further non-linear PID controlling in real time based on a flash based low power field programmable gate
array ( Microsemo Smartfusion A2F500M3G-FGG484). An intensity-modulated PWM module will be designed in
cortex-M3 for interfacing with CANDO Optrode to shine the light to cells with neurons which are genetically
manipulated to be sensitive to light for intervening epileptic–like seizures. This will be the exploratory reported flash-
FPGA based close loop neuroprosthetic micro-system in the market for intervening epileptic–like seizure implantable in
freely moving transgenic rodents for lower power consumption. Further biomedical experimental measurements on
rodents will verify the system performance.
Unclonability as a Security Enabler
Konstantinos Goutsos, Alex Bystrov and Alex Yakovlev
As networked devices are increasingly becoming a part of everyday life, they are starting to penetrate even the most
sensitive of sectors. This leads to a need for elevated security which will not get in the way of progress. We believe that
one of the most promising areas in this effort for improved security are protocols and methods making use of the notion
of unclonability. In this paper we introduce the concept in the context of system security and propose some first steps
for exploiting unclonability along with discussing some of the practical constructions that offer unclonability in
electronics.
Furthermore, being firm believers in the need for a closer mapping between human organisation structures and machine
network topologies, we make a first attempt at modelling these relationships. The resulting formalisation of the issue
will help create protocols that advance the goals of security while not hindering the usability of the systems.
28
Power and Energy Normalized Amdahl’s Speedup Model for Heterogeneous Many Core Computing
Mohammed A. Noaman Al-Hayanni, Ashur Rafiev, Rishad Shafik, Fei Xia and Alex Yakovlev
Continued technology scaling in VLSI has enabled more and more computation cores to be integrated in the same chip.
This has facilitated the parallelization of processing and the increase of performance whilst keeping energy
consumption at reasonable levels. To study the potential improvement of performance in such many core systems.
Amdahl’s law is the original speedup model that estimates the maximum performance improvement with fixed
workloads. This model is further extended via the Hill-Marty model to cover a limited form of heterogeneity. This
paper extends this model to cover a more comprehensive assumption of core heterogeneity. We also present power and
energy models based on the extended heterogeneous model. Our model cover popular power and performance control
methods such as Dynamic Voltage Frequency Scaling (DVFS), power gating, etc. A case study is performed with an
ARM big.LITTLE architecture containing Cortex A7 and A15 cores, including a comprehensive analysis with different
ratios of parallel and sequential workloads to identify the most energy-efficient system configuration based on this
model. Experimental results demonstrated high correlations between practically measured power normalized
performance and that of the proposed extended models.
Fast Capacitance-to-Digital Converter with Internal Reference
Kaiyuan Gao, Delong Shang, Fei Xia and Alex Yakovlev
Conventional capacitance-to-digital converters (CDC) widely used in IoTs particularly in portable applications tend to
make use of complex analog-to-digital technologies. However this can be power hungry and take long conversion time.
In addition, the analog parts are hard to implement in ASICs, especially under wide working conditions, such as energy
harvesting scenarios. Recently digitalized CDCs were proposed to meet these challenges, but existing solutions still
required long conversion time, and need external voltage references limiting their portability. A novel CDC with low
energy consumption and short measuring time is presented in this paper. With a new internal time reference method, it
is fully portable and achieves fast conversion response. A method of decoupling the sensing resolution from the
discharge mechanism enhances the programmability of such sensors making energy to precision tradeoffs
straightforward. This paper contains both theoretical analysis and the experimental demonstration of these methods.
This new solution can reduce the conversion time by more than 20 times, and reduce energy consumption by half.
A Smart All-Digital Charge to Digital Converter
Yuqing Xu , Delong Shang, Fei Xia and Alex Yakovlev
Capacitance sensors, that report the values of capacitances as digital codes, are important in such areas as biomedical,
environmental, and mobile applications. Voltage sensors are also widely used in many modern application areas, e.g.
where battery life information is important. Conventional capacitance sensing methods use complex ADC techniques
that are power hungry, and existing digital solutions, which use the charge to digital conversion (CDC) method tend to
suffer from slow sensing response. A novel dual-use all-digital CDC method is proposed in this paper, which can be
used to sense either capacitance values as a capacitance sensor or voltage levels as a voltage sensor. It shows low
power/energy consumption and fast sensing response.
Energy-Efficient Approximate Multiplier Design using Bit Significance-Driven Logic Compression
Issa Qiqieh , Rishad Shafik, Ghaith Tarawneh, Danil Sokolov and Alex Yakovlev
Approximate arithmetic has recently emerged as a promising paradigm for many imprecision-tolerant applications. It
can offer substantial reductions in circuit complexity, delay and energy consumption by relaxing accuracy requirements.
In this paper, we propose a novel energy-efficient approximate multiplier design using a significance-driven logic
compression (SDLC) approach. Fundamental to this approach is an algorithmic and configurable lossy compression of
the partial product rows based on their progressive bit significance. This is followed by the commutative remapping of
the resulting product terms to reduce the number of product rows. As such, the complexity of the multiplier in terms of
logic cell counts and lengths of critical paths is drastically reduced. A number of multipliers with different bit-widths
29
(4-bit to 128-bit) are designed in SystemVerilog and synthesized using Synopsys Design Compiler. Post-synthesis
experiments showed that up to an order of magnitude energy savings, and reductions of 65% in critical delay and almost
45% in silicon area can be achieved for a 128-bit multiplier compared to an accurate equivalent. These gains are
achieved with low accuracy losses estimated at less than 0.00071 mean relative error. Additionally, we demonstrate the
energy-accuracy trade-offs for different degrees of compression, achieved through configurable logic clustering. In
evaluating the effectiveness of our approach, a case study image processing application showed up to 68.3% energy
reduction with negligible losses in image quality expressed as peak signal-to-noise ratio (PSNR).
Energy Efficient Bootstrapped CMOS Inverter for Ultra-Low Power Applications
Mohammed Al-daloo, Alex Yakovlev and Basel Halak
This paper describes an energy efficient bootstrapped CMOS inverter for ultra-low power applications. The proposed
design is achieved by internally boosting the gate voltage of the transistors (via the charge pumping technique), and the
operating region is shifted from the sub-threshold to a higher region, enhancing performance and improving tolerance to
PVT variations. The proposed bootstrapped driver uses fewer transistors operating in the sub-threshold region, and
consists of two stages. The first stage is a normal driver with PMOS and NMOS transistors that are driven by the
enhancing voltage circuit (stage 2) which generates voltage levels theoretically between -VDD for pulling up to 2VDD
for pulling down. Our analysis shows that the proposed implementation achieves around 20% reduction in energy
consumption compared to conventional designs under a supply voltage of 0.15V VDD.
A Workflow for the Design of Mixed-signal Systems with Asynchronous Control
Vladimir Dubikhin, Alex Yakovlev and Danil Sokolov
This paper presents a novel workflow for the design of mixed-signal systems. Current methods rely
on synchronous control logic and full-system simulation, which might lead to suboptimal results and even project
respins due to critical errors. The proposed workflow aims to combine state-of-the-art tools for asynchronous circuit
design and formal verification of analogue systems in a unified environment.
Power-Aware Performance Adaptation of Concurrent Applications in Heterogeneous Many-Core Systems
Ali Majeed Aalsaud, Rishad Shafik, Ashur Rafiev, Fei Xia and Alex Yakovlev
Modern embedded systems execute multiple applications, both sequentially and concurrently. These applications are
exercised on heterogeneous platforms generating varying power consumption and system workloads (CPU or memory
intensive or both). As a result, determining the most energy-efficient system configuration (i.e. the number of parallel
threads, their core allocations and operating frequencies) tailored for each kind of workload and application scenario is
extremely challenging. In this paper, we propose a novel runtime optimization approach with the aim of achieving
maximized power normalized performance considering dynamic variation of workload and application scenarios.
Fundamental to this approach is a comprehensive study to investigate the tradeoffs between inter-application
concurrency with performance and power consumption under different system configurations. Using real experimental
measurements on an Odroid XU-3 heterogeneous platform with a number of PARSEC benchmark applications, we
model power normalized performance (in terms of IPS/Watt) underpinning analytical power and performance models,
derived through show that with increasing number of concurrent CPU intensive applications show variable gains in
IPS/Watt compared to the memory intensive applications in both sequential and concurrent application scenarios.
Furthermore, we demonstrate that it is possible to continuously adapt system configuration through a low-cost and
linear-complexity runtime algorithm, which can improve the IPS/Watt by up to 125% compared to the existing
approach.
Derivation of the Reliability Metric for Digital Circuits
Mohamed Abufalgha and Alex Bystrov
30
A new method of evaluation of reliability of combinational circuits uses two levels of characterisation: a Stochastic
Fault Model (SFM) of the component library and a design-specific Critical Vector Model (CVM). The idea is to move
the high-complexity problem of stochastic characterisation of parameters into the generic part of the design process, and
do it just once for a great number of the specific designs. The SFM captures variations of the vector of parameters of a
library component fault model, those causing a transient fault at the component output; it is meant to be supplied by the
foundry, similar to timing library files. The CVM is derived by a limited number of simulation runs on the specific
design, and represents the boundary between the erroneous and error-free operation, w.r.t. the vector of parameters of
each component. The probability of error-free operation is subsequently calculated by jointly using SFM and CVM. The
method is demonstrated on a chain of inverters for simplicity, and subsequently applied to a single path derived from an
ISCAS benchmark circuit. A complex three-way trade-off between energy, performance and reliability is explored.
Multiple paths and fault masking effects are not discussed. The method is meant to serve as a basis for design-time
reliability evaluation and run-time power-reliability management
Energy-Efficient, Smart Security Vision System Design using Significance Driven Learning
Dave Burke and Rishad Shafik
The historical evolution of the internet and embedded systems has seen massive growth in the performance of hardware
components and sub systems in terms of processing power, data transfer rates and data storage capacity. This has
enabled furnishing of data centres that can accommodate the huge quantity of data to be stored and the complexity of
applications to process these large amounts of data. Embedded systems are typically evolving with the same sort of
developments as sensor data and their data rates are becoming larger.
Typically increases in performance have been met by shrinking device geometry, offering faster clock rates and
therefore faster performance however this comes with a penalty that as you increase the clock rate the power
consumption increases linearly to the clock rate. This increased power consumption is now a significant issue with data
centres and server farms and could become a significant issue for embedded systems as sensor processing complexity
and data rates increase.
Devices and Printed Circuit Boards (PCBs) have come to a practical limiting frequency around 3GHz and the use of
Multiprocessor systems was left as the only way to increase performance, again resulting in an increase in power
consumption. The next generation evolution of heterogeneous systems is seeing combinations of asymmetric
multiprocessing coupled with Graphics Processing Units (GPUs) and Field Programmable Gate Arrays (FPGAs) as
ways of improving the power consumption to performance ratio. The system design of heterogeneous systems produces a
new challenge for design tools. System designers will need to estimate and select combinations of processor, GPU and
FPGA to give the desired performance and power usage against the specific tasks to be executed, rather than just
throwing an array of high performance processors at the solution. Other key topics in this process are management of
the running tasks in a Real Time
Operating System (RTOS) and power gating in order to minimise power consumption. The introduction of Internet of
Things (IoT) embedded devices has highlighted a serious number of security issues which has become a highly
focussed area which needs to be addressed in future embedded systems. This research is to look at ways of analysing,
fixed camera position, Ultra High Definition (UHD) camera video, initially, utilising Computer vision software
techniques to extract relevant information from the data stream, within user defined and prioritised polygonal Regions
of Interest (RoIs), for onward transmission to a storage or image processing utility. The background, slowly changing
data, will be transmitted at a lower frame rate.
In this way all elements can be recorded or processed to display a re-constructed image as seen by the camera. A further
stage of this research will be to analyse the image processing algorithms to identify areas of software that can be
accelerated by the use of FPGAs hardware and reduce the overall power consumption
Automated translation of asynchronous concepts to Signal Transition Graphs
Jonathan Beaumont
Asynchronous circuits are becoming increasingly important in system design for Internet-of-Things, where they
orchestrate the interface between big synchronous computation components and the analogue environment, which is
inherently asynchronous and has high uncertainty with respect to power supply, temperature and long-term ageing
31
effects. However, wide adoption of asynchronous circuits by industrial users is hindered by a steep learning curve for
asynchronous control models,such as Signal Transition Graphs, that are developed by the academic community for
specification, verification and synthesis of asynchronous circuits. Previously, we have introduced a novel high-level
description language for asynchronous circuits, which is based on behavioural concepts – high-level descriptions of
asynchronous circuit requirements, that can be shared, reused and extended by users. In this paper we will discuss more
examples using concepts, and an algorithm to automatically translate these to Signal Transition Graphs for further
processing by conventional asynchronous and synchronous EDA tools, such as PETRIFY and MPSAT. Our aim is to
simplify the process of capturing system requirements in the form of a formal specification, and to promote behavioural
concepts as a means for design reuse. The proposed design flow is fully automated in open-source toolsuite
WORKCRAFT.
Design of Control and Datapath of Scenario-based Hardware Systems
Alessandro De-Gennaro
One of the possible approach to the design of hardware systems is to start with the description of their behaviours. Each
of them represents a task that the system is supposed to execute. A task, also known as scenario, is nothing else but the
set of operations which need to be performed in a certain order for the achievement of the requested answer.
This has been validated with the design, fabrication and verification of an asynchronous reconfigurable pipeline (using a
miniASIC with TSMC 90nm technology). The models and tools used are available in the open source Workcraft
framework. Other models and theories for the synthesis of scenario-based hardware systems are also considered and
briefly examined, in order to picture the benefits that the presented design-flow comes with.
Emerging Technology and Materials (ETM) Research Group
Presentations
Facile Strain Induction in Monolayer MoS2
Johannes Gausden
Two dimensional materials have received signifi- cant interest over the past decade. Their low mass coupled with their
high tensile strength make them an excellent option for use within nano-electro- mechanical systems. There has also
been signif- icant interest surrounding bandgap engineering of two dimensional semiconductors via the local appli-
cation of strain. A rapid, facile method for the in- duction of localised strain within MoS2is presented which is fully
compatible with modern silicon tech- nology, and is anticipated to be fully transferable to all two dimensional materials.
The role of Carbon Vacancy in 4H-SiC
Hind Alsnani , Jonathan Goss and Alton Horsfall
This paper presents the results of carbon vacancy calculations for 4H-silicon carbide (SiC). Theoretical investigations
based on the density functional theory techniques are used to provide information on the ionisation levels of the VC
defects and the thermodynamic stability of the different charge states. Changes to the band structure of SiC with the
introduction of carbon vacancies enables a direct comparison between the calculated defect levels and those that have
been identified experimentally using techniques such as deep level transient spectroscopy. The energy level of the
double negatively charged state, that is thermodynamic stable, indicates that the Z1/2 centre, which limits the carrier
lifetime in SiC originates from a carbon vacancy.
Critical Field for Complete Impurity Ionisation Below Carrier Freeze Out Temperatures
Luke Bradley, Glynn Atkinson and Alton Horsfall
32
The field induced ionisation of dopants within semiconductors dramatically increases the suit- ability of semiconductor
devices for applications at liquid helium temSperatures. It is shown that carriers with sufficient kinetic energy are
capable of ionising shallow dopants at temperatures where the majority of carriers have frozen out. The ionisation
fraction of dopants reaches unity at field strengths above a critical field value. The critical field for ionisation increases
with dopant concen- tration as the resulting decrease in carrier mobility reduces the kinetic energy of free carriers. The
ionisation mechanism is of great benefit for semi- conducting devices functioning at temperatures well below the carrier
freeze out temperature with Ge being highlighted as the optimal material for power devices.
SiC MOSFET
Faiz Arith, Jesus Urresti, Konstantin Vasilevskiy and Anthony O'Neill
Investigating improvements in MOS mobility for SiC MOSFETs, we report the introduction of an ultrathin SiO2 layer
between Al2O3 gate dielectric and 4H-SiC interfaces. By using Angle Resolved X-Ray Photoelectron Spectroscopy
(ARXPS), we confirmed that the SiO2 is grown and the thicknesses is well defined. From our results, by introducing
the ultrathin SiO2 layer at low temperature condition underneath Al2O3, the density of interface traps are reduced
significantly. This ultrathin layer exhibited a good interface layer between 4H-SiC and Al2O3. Specifically, we
believed that thermally grown SiO2 generates single interstitials carbon atom (Ci) that can eventually bind to each other
and form immobile carbon clusters like (Ci)2 giving rise to a increment of the density of interface traps. Furthermore,
the combination of Al2O3 and ultrathin SiO2 produces an adequate barrier height to render a low leakage current.
Low Energy X-ray Detection in 4H-SiC Schottky Diode at Elevated Temperatures
Nurul Mohamed , Nick Wright and Alton Horsfall
The superlative material properties make silicon carbide radiation hard and this ability has enabled it to be demonstrated
in a range of detector structures for deployment in extreme environments, including those where the ability to tolerate
high radiation dose is imperative. This includes applications in space and nuclear environments, where the ability to
detect highly energetic radiation is important. In contrast, detectors used in medical treatment, such as imaging and
radiotherapy, uses a range of radiation dose rates and energies for both particulate and photonic radiation. Here, we
report the response and linearity of detectors fabricated from silicon carbide to dose rates in the range of
0.185mGy.min-1, typical of those used for medical imaging purposes. The data show that the radiation generated
current originates within the depletion region of the detector and that the response is linearly dependent on the volume
of the space charge region. The realisation of a vertical detector structure, coupled with the high quality of epitaxial
layers, has resulted in a linearity and sensitivity of the detector that are more than four orders of magnitude higher than
those published previously for similar dose rates. The temperature dependence of the characteristics indicate that silicon
carbide Schottky diode based detectors offer a performance suitable for medical applications at temperatures below 100
C without the need for external cooling.
Towards accurate, fast and large scale Kohn-Sham DFT.
Tiago Marinheiro
Towards accurate, fast and large scale Kohn-Sham DFT. The power of Density Functional Theory (DFT) property
prediction has led to its acceptance in a variety of fields. But for all its success at predicting a material properties, DFT
suffers from a bottleneck problem, large and accurate calculations can take a prohibitively long time. Most of the
widely used codes nowadays use plane waves as a basis sets. From a theoretical point of view plane wave basis offers
systematic convergence, but they are one of the most computationally expensive methods. Meanwhile, Gaussian basis
sets are not as easy to converge, but results can be obtained in much shorter timescale for small and medium sized
systems, providing a good complement to plane wave codes. As large scale calculations become more important for
accurate results such as in point defect studies, the necessity for a code with plane wave accuracy and a small
computational overhead. A brief explanation of DFT using Gaussian basis sets is given. A procedure is shown which
greatly simplifies the generating of Gaussian basis sets to bring it on par with the accuracy of plane waves (the first step
in obtaining large and accurate DFT calculations). A benchmark calculation, which is used to compare different codes
and produced and averaged “error” value, is used to assess the basis generating procedure
33
34
Characterization of nickel-nanoparticles embedded in silica aerogel
Sherko Ghaderi , Sarah Olsen, Lidija Siller, Khalil Hassan and Xiao Han
Silica aerogel embedded with nickel nanoparticles (NP) is characterized and considered as a potential thermoelectric
material. The thermal conductivity, electrical resistivity, and Seebeck coefficient have been analyzed as the density of
NiNP are increased from 0 to 700 ppm. The results suggest that optimizing the density of NiNP could yield promising
thermoelectric properties. The electrical resistivity is found to be highly sensitive to the density of NiNP, while the
thermal conductivity remains unchanged. The samples exhibit (10)^6 improvement in power factor when the density of
the NiNP is increased from 0 to 700 ppm. This arises from metallic percolation networks developing which improve the
electrical conductivity. Material composition is analyzed using Raman spectroscopy, the electrical resistivity is assessed
using four-point probe techniques and thermal conductivity is measured using HotDisk measurements and scanning
thermal microscopy (SThM). All measurements were performed at room and elevated temperatures. By using SThM,
characterization of individual NiNP clusters is possible.
Instability of phosphorous doped SiO2 in 4H-SiC MOS capacitors at high temperatures
Muhammad Idzdihar Idris, Alton Horsfall and N.G. Wright
In this paper, the effect of inclusion of phosphorous (at a concentration below 1%) on the high temperature
characteristics (up to 300°C) of the SiO2/SiC interface is investigated. Capacitance – Voltage measurements taken for a
range of frequencies have been utilized to extract parameters including flatband voltage, the effective oxide charge and
the interface state density. The variation of these parameters with temperature has been investigated for bias sweeps in
opposing directions and a comparison made between phosphorous doped and as grown oxides. At room temperature,
the effective oxide charge for SiO2 may be reduced by phosphorous termination of dangling bonds at the interface.
However, at high temperatures the effective charge in the phosphorous doped oxide remains unstable and effects such
as flatband voltage shift dominates the characteristics. The instability in these characteristics was found to result from
the trapped charges in the oxide (±1012 cm-3) or near interface traps at the interface of the gate oxide and
semiconductor (1012 ~1013 cm-2eV-1). Hence, the performance enhancements observed for phosphorous doped oxides
are not realised in devices operated at elevated temperatures.
Investigation of the migration mechanisms and diffusion of Cd in CZTS/CdS heterojunction
Fatimah Bahrani , Jonathan Goss and Patrick Briddon
The interface between CZTS as an alternative absorber for low cost thin film and the CdS buffer layer is one of the
most important issues affecting CZTS/CdS cell performance. The determination of the activation energy through the
interface is a crucial point for the high-efficiency CZTS cell. The diffusion barrier across the heterojunction interface
for the CZTS/CdS cell was determined on the basis of the first-principles calculations. The charge-neutral substitution
defect CdZn has the lowest formation energy (0.035eV), so that it can be formed easily in the hetero-structure interface.
In this study, the results revealed that there is a diffusion of Cd, Cu, and Zn at the epitaxial interface
CdS(100)/CZTS(100), that the dominant diffusion defects via the heterojunction interface CdS/CZTS is the neutral
charge CdZn, and that the diffusion barrier of CdZn is about 2.1eV.
35
Abstracts
Communications, Sensors, Signal & Information Processing
(ComS2IP) Research Group
(Posters)
Crack Detection and Characterisation System for Metallic Structures Using Chipless RFID Tag Sensor
Adi Mahmud Jaya Marindra and Gui Yun Tian
Passive chipped RFID sensor systems have been studied for structural health monitoring (SHM) applications on
metallic structures. However, the use of silicon chip makes RFID tags not economical enough and unable to work in
extreme environments. This research proposes chipless RFID sensor system for crack detection and characterisation on
metallic structures. The system consists of a metal-mountable chipless RFID tag, which is attached onto the monitored
metallic surface; and a reader, which performs signal transmission and reception, signal processing and feature
extraction. This research aims to explore feasibility of chipless RFID for crack detection and characterisation on
metallic structures and overcome challenges, such as sensing sensitivity, resolution, and read distance, by optimising the
sensor design and the reader. A feasibility study through simulations shows that chipless RFID system has great
potentials for crack detection and characterisation.
Sensory Feedback in Prosthetic Limbs
Ana Carolina Pinto Da Silveira, Emma Brunton and Kianoush Nazarpour
In the event of limb loss, prosthetic devices have been able to restore some functionality, enabling the user to regain
independence. Even though these devices are increasingly sophisticated, prosthetic limbs do not provide sensation to the
user and are not able to rival the functionality of the natural limbs [1], [2]. The aim of this project is to contribute to the
next generation of prosthetic devices that will provide sensory feedback through neural interfaces. Neural interfacing
technologies, differing on their level of invasiveness, selectivity of stimulation and electrode-density, will be compared
by performing in vivo experiments in animal models. The experiments will be divided into acute and chronic, where
both peripheral nerve recording and stimulation will be performed. The goal is to be able to discriminate the recorded
sensory afferent signals using classification algorithms and to then use this information to stimulate peripheral nerves
and, therefore, provide sensory feedback.
Multimodal Wide Area Surveillance
Federico Angelini
This work will focus upon Machine Learning and Fusion Techniques for the automatic analysis of multimodal wide
area sensor measurements. The aim is to obtain a robust model for human activity based on video camera data in order
to estimate abnormal behaviour. Wide area surveillance is a thriving field, providing plenty of challenges. One of the
most interesting is the human behaviour recognition in public environment, with special focus on situation awareness
and prompt reaction in case of suspicious events. Techniques related to face/gaze/head/body recognition,
gesture/posture recognition, skeleton estimation and modelling of human activities are involved in this project. The
work would align with activities within the University Defence Research Collaboration (UDRC) and the opportunities
to work with the academic and industrial partners, in particular Thales, which is also providing real world data for
testing (supporting preliminary testing based on CAVIAR dataset). Facilities within the new Intelligent Sensing
Laboratory at Newcastle University will also be available for this work.
36
Cognitive Radio Approach and Implementation for Smart V2X Communication
Haicang Li
Efficient, secure and reliable, vehicular communication is one of the critical parameters in the intelligent transport
system, and is the next generation research and application which has the potential to ease traffic and provide safety to
drivers and road users. Vehicle to vehicle (V2V) and vehicle to anything (V2X) communication can share security,
safety related and general messages between vehicles within the radius of a 1-2 km vehicular network, and
infrastructure and with emergency vehicles within the radius stated in WAVE protocol. There are enormous channels
for communication between every node within a vehicular network and the topology of this network is mobility and
dynamic which add challenges to have efficient V2X communication in the urban environment. Therefore, improving
the capacity and efficiency is one of the most critical things in a vehicular network. Cognitive radio is based SDR
(Software Defined Radio), can detect and access unoccupied channels in wireless spectrum. It is reprogrammable and
reconfigurable to change the parameters of its communication dynamically. The major benefit of having cognitive radio
is that the efficiency and capacity of the vehicular network can be improved significantly. This study focuses on using
SDR for safe, secure V2X communication for next generation intelligent transport system.
A Review of Intrusion Detection Schemes for IOT
Monika Roopak, Prof Gui Yun Tian and Jonathon Chambers
The future of the Internet is emerging on the basis of the concept of the Internet of Things (IoT). It promises to create a
world where all the objects around us are connected to the Internet and communicate with each other without human
interference. The IoT has to implement a proper security mechanism such as encryption and back up of data,
authenticate users and applications and integrity assurance of processed and stored data in the system. In theory IoT
system is secure of all the necessary security mechanisms are in place, however the situation is not be simple as that.
The protective mechanisms alone are not sufficient to provide adequate security for a system. It is important that IoT
systems are also equipped with a proper second line defence mechanism that can be used to detect and analyse security
incidents therefor the Intrusion Detection System (IDS). In this poster, we review various intrusion detection
approaches to mitigate those attacks in IOT.
Cooperative Communication in Vehicular Ad-Hoc Networks
Scott Stainton
In this research, cooperative communication using relays is proposed as a solution to mitigate the harsh effects of
vehicular channels and maximise throughput under varying conditions. Throughout, the research is focussed on abiding
by the IEEE 802.11p standard for Wireless Access in Vehicular Environments (WAVE) with specific attention being
paid to having practical applications in the Intelligent Transport Systems (ITS) sector. Due to the highly mobile nature
of vehicular ad-hoc networks (VANETs), many existing techniques become suboptimal as the network topology
changes rapidly. It is hoped to be shown that through the efficient use of relay selection and relay processing protocols
that the overall system performance can be optimised even when the direct link between the transmitter and the receiver
is weak. This research will focus on the creation and repurposing of algorithms to achieve these tasks, while being
mindful of the strict latency requirements imposed by the WAVE standard.
Model-Based Robust Speech Separation
Yang Xian, Mohsen Naqvi and Jonathon Chambers
My research project focuses on the analysis, design and evaluation of statistical signal processing methods and
computational auditory scene analysis (CASA) based method to address the machine cocktail party problem (MCPP).
The statistic signal processing based on principle component analysis (PCA),independent component analysis (ICA)and
independent vector analysis (IVA). The CASA based well-know MESSL with Student's t-distribution is reviewed in
this report. More specifically, the Student's t-distribution are used to model binaural cues such as distributions of
interaural phase difference (IPD) and interaural level difference (ILD). The maximization of log likelihood function is
37
realized by expectation-maximization (EM) algorithm. Finally, the probabilistic time-frequency (TF) masks are
obtained, which are used to separate sources. The experimental results based on TIMIT data base and BRIRs data base
shows signal to distortion ratio (SDR), perceptual evaluation of speech quality (PESQ) and short time objective
intelligibility of Student's t-distribution mixture models (SMMs) outperforms Gaussian mixture models (GMMs). In
future work, binaural and monaural statistical models will be studied for robustness BSS.
Emerging Technology and Materials (ETM)
Posters
Graphene Hall Sensors for Harsh Environment Current Sensing
Amy Peters, Alton Horsfall and Nick Wright
Whilst current sensing techniques are advanced, their sensitivity to high temperatures somewhat limits their use in
power electronics applications. The 2-D nature of graphene along with its exceptional electronic properties such as high
carrier mobility (~10,000〖cm〗^2 V^(-1) s^(-1)) and high thermal conductivity makes it an ideal material for the
realization of highly sensitive, low-noise Hall sensors capable of operating at high temperatures. These properties are
true only for suspended graphene as when fabricated on a substrate it is transfer doped leading to degradation of its
electronic properties, particularly the carrier mobility. Indeed, there are many limitations in graphene device design,
namely in its sensitivity to the surrounding environment. Chemical contamination from conventional lithographical
processes results in degradation of electronic properties with high contact resistance at the metal/graphene interface also
being a significant challenge. Methods into reducing this chemical contamination and achieving a low contact resistance
need to be investigated in addition to optimizing the electronic properties of graphene when fabricated on a substrate.
Optimization Considerations for Thermoelectric Generators
Hector Gabriel Galvan Brugal and Sarah Olsen
Cheap, clean, and reliable energy is one of the greatest challenges ever presented to researchers. Photovoltaic cells, tidal
power, and wind farms are good sources of clean energy, but are expensive. A recent trend also requires energy to be
mobile. Thermoelectric-based generators are the cost-effective solution to applications which require clean, mobile
energy. The aim of this research is to develop efficient designs for wearable thermoelectric generators. This
optimization will consider advanced thermoelectric materials, contact resistance and device geometry.
Calculated electron affinity and stability of Aluminium Oxide terminated diamond
James Beattie and Jon Goss
Chemically engineering a materials surface to exhibit an NEA (Negative Electron Affinity) is desirable, as it lowers the
potential barrier for electron emission. Hydrogen terminated diamond exhibits an NEA but is unstable at high
temperatures where it desorbs from the surface above 700oC. Desorption reverses the NEA back to a PEA making it ill-
suited for high power operations. Using the quantum mechanical modelling software AIMPRO, calculations are
performed to assess the viability of varying Aluminium Oxide stoichiometry’s and geometries on the 111 surface of
diamond. Finding the most energetically favourable termination with a binding energy that can withstand temperatures
above that of Hydrogen as well as an NEA in the region of 1-2eV could prove Aluminium oxide to be a suitable
termination choice for device applications.
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The Fabrication of Silicon Carbide Gas Sensors for use in Automotive Applications
Ryan James Siddall, Alton Horsfall and Nick Wright
The aim of my project is to produce a silicon carbide metal-oxide-semiconductor (MOS) gas sensor capable of
selectively monitoring automotive exhaust gases. In order to meet the upcoming changes to European legislation,
selectivity to nitrogen oxides (NOx) and carbon monoxide (CO) will be focused upon. An investigation into the
influence of the high-κ dielectric and catalytic gate metals on the selectivity to different gases in the exhaust mixture
will be carried out. A number of different materials will be incorporated into the device structure to selectively target
gases. Working in collaboration with an industrial partner, Littelfuse, the aim of this work is to develop laboratory
prototypes from conception into fully functional devices capable of meeting the required performance specifications of
the automotive industry. The ultimate goal is to produce a reliable, fully contained and stable sensor system which can
be packaged and integrated into a vehicle with ease.
Magnetron sputtering magnetostriction film for characterisation and sensing application
Yu Tang and Sarah Olsen
Magnetostriction is the effect of changes in physical dimensions by an applied magnetic field or vice versa.
Magnetostrictive materials can be exploited in many applications including micro-drivers for servo motors, actuators,
sonar and sensing applications. In a magnetostrictive sensor, the change in dimension arising from the magnetization
may be detected. This can be used for force, torque or displacement sensing, or liquid level detection. In addition to
exhibiting high magnetostriction, galfenol (iron-gallium) benefits from machinability and mechanical robustness. In this
project magnetostrictive films such as galfenol will be developed for sensing applications using magnetron sputtering.
The sensor films will be characterised using a variety of techniques including magnetic force microscopy, x-ray
diffraction and vibrating sample magnetometry. The change in magnetostriction with external circumstances will be
evaluated.
μSystems Research Group
Posters
Design Methods for Minimum Energy Point Asynchronous Processors in the Internet of Things
Adrian Reece Wheeldon
As internet of things devices become increasingly abundant, the need to minimise their energy consumption becomes
evermore important. This research will concentrate on processor design for the internet of things, specifically focused
on the use of asynchronous (clockless) digital logic. While asynchronous design has been around for decades and can
offer many advantages, it remains underutilized in industry, presumably due to its more formal design process and
underdeveloped design tools when compared with synchronous design. The research covers four areas of processor
design using asynchronous design methodologies, and works towards wider adoption of asynchronous design. The areas
include design partitioning, memory architecture, parameterised circuits, and instruction set architecture; all of which
will enable improved energy efficiency. Throughout, special consideration will be given to the design process, and
effort made to improve existing (or create new) design flows in an attempt to push asynchronous design into wider use.
Wireless Energy Transfer and Communication for Implantable Medical Devices
Banafsaj Rasool and Patrick Degenaar
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One of the most important and challenging disciplines in this era is the implantable medical devices. Particularly,
Increasing concern to improve the blind peoples’ life by developing and implementing a new visual aid. The major goal
of this research is to implement a novel design of visual cortical implant as a visual aid for blind people. The implanted
visual cortex prosthesis, by using an implanted optoelectrode (optrode) array, will be capable of firstly optically
stimulate the visual pathway and generate a spatial pattern of visual precepts so-called phosphens, secondly
electronically recording the field potential and send this information back to the external system. The key challenging in
this field is those related to the power consumption which resulting a fast depletion in the implants battery life. In
addition, the data link which required a high rate and small latency. This system will be implemented with the acoustic
power transfer and wireless data transfer characteristics.
RF Energy Harvesting system
Danhui Li
There are a variety of RF signals including TV, cellular and WIFI transmission, intriguing the widely use of RF energy
harvesting technologies. WISP is a typical RF energy harvesting application refers signal sensing, data processing and
wireless communicating capabilities. As RF signal in the environment is not stable, energy efficiency is the key issue
that needs to promote for the purpose of improving the life span of the battery in the RF energy harvesting system. In
energy harvesting system based on piezoelectric transducers, high-efficiency power delivery methods such as Switched
Capacitor DC-DC Converter (SCC) and Capacitor Bank Block (CBB) are developed. However, in the RF energy
harvesting system the high efficiency of these power delivery is need to be verified.
Self-Timed Control of Two-Phase Switched Capacitor Converters
Serhil Mileiko, Alexander Kushnerov, Danil Sokolov and Alexandre Yakovlev
The paper considers the shoot-through currents in two-phase switched capacitor converters (SCCs) as switching
hazards. Despite the fact that the existing control circuits provide safe operation, there is no formal method to
synthesize such circuits for multiphase SCCs. Besides that, the existing circuits are synchronous and therefore do not
sustain large changes in the operating conditions. The paper shows how one can use a CAD tool for designing
asynchronous circuits to synthesize an SCC controller and thereby alleviate both of the above-mentioned drawbacks.
The obtained circuit is self-timed, i.e. does not require external clock and has low sensitivity due to inherent negative
feedback.
Computational Costs of State-of-the-art Algorithms for Read Alignment in Whole Genome Sequencing
Sidharth Maheshwari, Rishad Shafik, Alex Yakovlev and Ian Wilson
Whole genome sequencing (WGS) is leading from the front in the current revolution underway in medicine to transform
it from reactive to preventive. WGS facilitate predictive, preventive, participatory and personalized (P4) form of
medicine through continuously decreasing cost of genome sequencing and technological advancements in the
sequencing instruments. This, however, posits immense pressure on the computing resources to crunch large amounts of
data in a reasonable time and energy framework. Among the two categories of algorithms for genome assembly viz. de
novo assembly and read alignment, we study the state-of-the-art algorithms in the latter, owing to its runtime
advantages, to characterize w.r.t energy, peak power, and runtime and memory utilization in order to propose
approximate computing solutions. We study all the major algorithms, proposed in the last decade since the arrival of
next generation sequencing, and report the run-time and resource utilization.
Low-power QDI design using novel device and interconnect technologies
Thanasin Bunnam, Danil Sokolov and Alex Yakovlev
Recently, various computing device and interconnect technologies, for instance carbon nanotube and silicon nanowire,
were invented due to the limitations of CMOS technology in nano-scale circuits. Although they revealed a great
promising performance, they suffered from fabrication process variabilities which caused leakage and timing variation
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problems and finally reduced circuit yield. In the meantime, Quasi-Delay-Insensitive (QDI) design has been considered
to be an approach for designing low-power time-invariant circuits because of its event-driven property inherited from
the asynchronous circuit.
This research will investigate on process variability problems of the novel device and interconnect technologies and a
solution using QDI design approach. Therefore, the expected result will be an approach that is able to enhance power
efficiency, variation robustness and yield of the circuit. To evaluate this, the experiments will be conducted by
statistical analysis with process variation probability and power analysis between the proposed design and the
traditional one.
Electrical Power (EP) Research Group
Posters
Development of a Double-Sided Linear Vernier Hybrid Machine for Direct Drive Wave Energy Converters
Ahmed Almoraya, Nick Baker and Kristopher Smith
In recent years, low speed high thrust force linear permanent magnet (PM) machines which are suitable for direct drive
wave energy converters have attracted the attention of many researchers. In literature, a linear veriner hybrid permanent
magnet (LVHPM) machine with inherent magnetic gearing was proposed for direct drive wave energy converters.
However, since the magnets with alternating polarity are used in this class of machine, a large amount of PM material is
required leading to high initial cost. This project aims to develop a double-sided LVHPM machine with less than 50%
PM mass resulting in low capital cost. The consequent pole technique is adopted in the new machine where one polarity
of PMs is replaced with ferromagnetic poles. This topology is capable of improving the main flux and the machine
performance consequently. The present machine is designed, analysed and compared with that of the conventional
LVHPM using finite element analysis (FEA).
Integrated Diagnostic System for Wind Power Generators
Cuili Chen , Volker Pickert and Charalampos Tsimenidis
IGBT power modules are the fragile part in wind power converter. Intensive research is focused on the reliability
improvement of power module to make the power system more trustworthy and cost-effective. This poster is mainly
about the state of art research on this area. First, an overview about the power module itself is provided along with the
general failure mechanisms. Second, reliability of power modules is introduced followed by a summary of approaches
aimed at reliability improvement. Then, pilot study about simulation and experimental test is presented including a
proposed method for online application. Finally, this research will mainly focus on signal process based method in the
future.
Power Pinch MPC - RL based Control for Adaptive Energy Management of an Integrated Hybrid Energy
Storage Smart Grid
Bassey Nyong-Bassey, Damian Giaouris, Shady Gadoue and Haris Patsios
In a hybrid RE microgrid, the use of predefined power management strategy (PMS) for optimal decision making
requires anticipation of all possible sequence of control and corresponding actions. The model predictive and
reinforcement learning (Q-Learning) control techniques may be used to explore and evaluate in advance the rewards of
undertaking several control actions for optimal (PMS). Therefore, this research work proposes to exploit the adaptive
shaping of the Power Pinch strategy for inferring the PMS with respect to demand side response load shifting within a
hybridised MPC and RL (Q-Learning) framework to enhance robustness to uncertainty. Also, the proposed method will
be exploited for RE grid sizing cost minimisation.
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Application of Wide Band Gap (WBG) Switching Devices in Automotive Integrated Machine Drives.
Bethany Hoare , Dave Atkinson, Simon Lambert and Barrie Mecrow
Wide Band Gap (WBG) switching devices have several characteristics that make them desirable for integrated drives.
They can operate at higher temperatures, voltages and frequencies. These features may enable a smaller, lighter
integrated drive system to be designed, a highly desirable opportunity for applications where weight and space are a
premium. The automotive drive company Protean have several modifications that they would like to make to their
existing product, it is thought that WBG technology will enable these changes. The first stage of research will be to
carry out a feasibility study in order to determine the expected benefits of a WBG based drive over its silicon
counterpart. The two WBG materials that will be considered are silicon carbide and gallium nitride, the material chosen
for the project will depend upon the results of the feasibility study and literature review.
Decarbonisation of the Chemical Industry through the deployment of Virtual Power Plants
Chaudhry Jibran Javaid , Damian Giaouris, Phil Taylor and Simon Blake
The Chemical Industry is a heavy user of energy and most of this energy is generated by using fossil fuels. Given the
UK target for 80% reduction in CO2 emissions by 2050 this situation will have to change. This is very challenging and
the chemical industry is a heavy energy user and fossil fuels have relatively high energy densities when compared to
renewable forms of generation. The proposed method and currently under investigation is that of the virtual power
plant. This concept seeks to use real time control and energy management of demand, variable generation, networks and
energy storage in order to present what appears to be a power plant capability to the grid. This means that although
behind the grid connection a number of relatively small stochastic sources and sinks of energy exist inside a micro grid
or sub network, from a point of common coupling to the grid the overall entity appears predictable, dispatchable and
responsive. This offers commercial, environmental and operational benefits. The research would examine three
scenarios:
• A very large centralised chemical plant with a grid connection capacity in the region of 500MVA.
• A small scale highly distributed form of chemical plant with a grid connection capacity in the region of 1 MVA.
• A mid-scale chemical plant with a grid connection capacity of approximately 50MVA that could be reduced to around
20MVA through the use of the VPP concept.
High-Frequency Machines using Soft Magnetic Composites
Dan Wood and Glynn Atkinson
This PhD programme will apply soft magnetic composite (SMC) machine design and new powder technology to the
area of high-speed electrical machine (HSEM) development. The programme aims to produce a high-speed SMC
electrical machine in several leading edge SMC low loss powders with an upgrade or paralleled performance compared
to a current commercially available lamination machine. Initially, a suitable application will be sought and material
measurement, machine design and overall development will run in synchronism. A status of mechanical, thermal, power
electronic switching element and other necessary associated limitations will be investigated and outlined and an outlook
for the future will be included. An intention of forming a link to work incorporation with a partner company for the
production of an optimised HS machine is also envisioned subject to the chosen application. Here the desired
application would be for an e-turbocharger, in a hybrid or combustion engine, used to spin a compressor to a required
speed when there is a lack of energy, and harness energy when there is an excess of energy.
Develop a Software Tool that Identifies the Technology Selection and Realisation of Inline Power Supply, Power
Electronics Drive and Drive Controller for a Defined Automotive Hybrid Vehicle Transaction Electric Machine
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Gashtil Hamidreza , Volker Pickert, Damian Giaouris, Mohamed Dahidah and Shady Gadoue
Using the powerful software tool, that can help manufacture to visualize and optimize the finalize performance, cost,
weight and volume of their productions, is the vital key in decreasing the expenditure and improving the outputs of
productions. The proposed software has an ability to expose the performance of control methods applied in drive
controllers for different type of machines such as IM, IPM, SynRM and PMaSynRM. Then, the operating performance,
cooling/ packaging requirements and operating efficiency should be evaluated in Inline Power Supply (which is
Interface between High Voltage Battery and Power Electronics Drive) and Power Electronics Drive (which is Interface
between Inline Power Supply and Electric Machine). Furthermore, the durability and cost verses performance impact of
power components used in power electronics and drives should be considered in the proposed software. Finally, An
Indication of Radiated EMI Based on the dv/dt and di/dt Waveforms will be presented in the software.
Control of Power Conversion Systems and Nonlinear Analysis
George Gkiza
The control design of power conversion systems is a challenging processes that demands special treatment due to their
complex nature. This complexity stems from their highly nonlinear dynamics, which can be attributed to their switching
action, as well as from the uncertainty that governs these kind of systems system concerning load, input and parameter
variations. As a result, advanced control design techniques need to be considered that take into account the nonlinear
behaviour of the system and provide robustness and satisfactory performance as well. The controlled design techniques
that need to be employed utilize polytopic models that incorporate the aforementioned uncertainties. However, the
challenge lays in incorporating the nonlinear phenomena that stem from the switching action of the power conversion
systems. This presents several challenges and it is an uncharted territory due to many problems that stem from the
mathematical point of view. The novelty of my research lays in the derivation of model that fully describes the
nonlinear behaviour of the system and can be used to directly apply control theory. This is of very high importance
since these kind of nonlinear phenomena can severely affect the operation of the system and deteriorate its performance
due to the increase of power loss and the violation of performance specifications.
Transverse flux machine for in-wheel applications
Iago Martinez Ocaña
Protean’s in-wheel motor offers an interesting solution for motor placing in electric vehicles. This project will develop a
new topology based on the Transverse flux machine (TFM) configuration. In a TFM the increase in power is
proportional to the pole number as the coil MMF is seen by all the poles, hence torque increases with electric loading.
The project will cover a study to show the capabilities of the TFM with the volume, and converter constrains, aiming to
demonstrate its high torque performance. Deeper study of the topology will be performed analytically and using Finite
Element Analysis (FEA) tools. Due to its unique flux path only 3D FEA models can be used, which require high
computational time. The use of analytical or reluctance networks calculations will speed up the design process. The
desired project outcome is to manufacture and test such novel machine.
System Identification of Multi-Rail DC-DC Power Converter
Jin Xu , Matthew Armstrong and Maher Al-Greer
Since the requirements of multi-rail DC-DC power converter include soft-start / shut-down, sequencing, margining,
fault management, fault recovery fault prediction and etc., adaptive control based on parametric system identification
would be introduced soon to obtain the detailed information of system operation and then adjust the controller into
optimized working conditions, which is the main topic of my future work. Meanwhile, as to multi-rail DC-DC
converter, an appropriate time schedule would be proposed to reduce reacting time of master auto-tuner and individual
controller.
Novel Advanced Powered Air Purifying Respirator (PAPR) Concepts.
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Jonathan Thompson , Steve McDonald, Barrie Mecrow and Simon Lambert
Powered air purifying respirators (PAPR) utilise a motor blower to provide a positive pressure in the mask of a
respirator. Recent breath responsive PAPRs perform well overall but suffer from a problem known as overbreathing,
whereby the demand volumetric airflow is larger than the supplied. To improve the breath responsive systems, current
models of the PAPRs available have been simulated in Simulink and will be compared against real data from a rig to
simulate a user breathing into said device. Once the simulated model has been validated it can be optimised for the best
possible system. Results show that the motor power density, weight and dimensions of the impeller, sensor response,
and the battery power density are the main limitations of the system’s response. A method is also being produced to
calibrate and even predict the user’s breathing pattern to customise the system for individuals.
Droop control method in DC/AC hybrid micro grid
Li Lei, Mohammed Elgendy and Neal Wade
Although there are many advantages of distributed generation (DG), there are still many problems, such as the cost of
stand-alone access is very high and difficult control. Furthermore, the distributed power supply is an uncontrollable
power supply relative to the power grid, which will have some disadvantages on the stable operation of the power grid.
In order to coordinate the contradiction between power grid and distributed power, and to promote the large-scale
integration and application of distributed generation, the concept of micro-grid is put forward. As a basic power
electronic interface unit in the micro grid, the micro grid inverter has a direct and reasonable control on the safe and
stable operation of the micro grid. In order to realize the dual-mode stable operation and the smooth switching between
two modes, this project will focus on the droop control strategy of micro grid inverter.
Next generation monitoring for enhanced asset management
Luke Burl
Real-time condition monitoring represents a large opportunity for power system network operators.
This is becoming more important due to ever-increasing challenges faced by the power systems and network operators.
To enable this real-time condition monitoring and asset management capability, a number of developments within the
power systems and ICT industries have occurred:
•Increased interoperability and data gathering capability due to the adoption of IEC61850
•Increased computational capabilities due to Cloud computing techniques
•Greater visibility of grid systems through additional smart enabled monitoring systems
•Availability of load, generation and weather forecasting techniques and data
•New novel smart sensor technologies
This PhD research project will investigate the application of these advances to condition monitoring and diagnostics for
future substations. The research will consider the technical feasibility of the next generation substation sensor
technologies and analytic techniques including machine learning and other Artificial Intelligence techniques to provide
useful information to operators and planners.
Research into Switched Mode Power Supplies for Consumer Products
Mark Turner
As consumer products keep improving and becoming more powerful. This means the technology that supplies this
power needs to also improve. When an applications power level increases, a battery with greater capacity would be
required to keep the same operating time or a higher capacity supply would be required if it is directly mains connected.
In order to maintain acceptable charging times with larger batteries, higher power level supply would be required.
Therefore, in both mains and battery powered cases, the power supply needs to be able to deliver more power to charge
a battery quicker or directly supply the application with sufficient power. As a result of these requirements, these power
supplies need to be very efficient. The most common used power supplies are switched mode power supplies (SMPS).
Increasing the size of the SMPS is not an option for increasing power capacity because they want to be decreased in size
for cost and aesthetic reasons. Therefore, the power density must be improved in line with the efficiency improvement.
This research will look into methods such as adding dual active bridges into the circuit and other techniques for making
the SMPS smaller and more efficient. Finally, consumer SMPS must meet certain European standards such as IEC
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1000-3-2 which has constraints of certain harmonic on the supply current which the SMPS can create which affects the
design and control of these supplies. Techniques such as unity power factor control and other techniques will be
reviewed to overcome this and meet the standards.
Stochastic Predictive Control of Switched Reluctance Motor
Najib K Dankadai and Mohammed Elgendy
This research will investigate the application of a stochastic model predictive controller (MPC) for direct instantaneous
torque control of a switched reluctance motor (SRM). In this project, an objective function of MPC will be developed to
ensure tracking of the desired torque as accurate as possible with low ripples, minimize winding currents and improve
system operation during normal and faulty conditions. The objective function of the MPC will be varying with time by
a fast and non-complex auto-tuning algorithm to cope with the SR machine uncertain inductance profile. The proposed
structure of the controller will also consist of a designed filter with the low computational cost to allow a fast response,
ambient noise rejection, and robustness. Finally, simulation and experimental results will be provided to demonstrate
the effectiveness of the proposed control scheme.
A new compact axial flux permanent magnet motor development for dishwasher using soft magnetic composites.
Nasiru Aliyu , Glynn Atkinson and Nick Stannard
With increasing demand for electric motors used in nearly all sectors of our day to day activities, which range from the
motor that rotates the washing machine and dishwasher to the tens of thousands of motors in the vehicle we drive. The
number of applications for soft magnetic composites (SMC) material is growing significantly. This paper presents the
development of a new compact single sided concentrated winding axial flux PM motor using soft magnetic composite
as core for reducing core losses and cost. The effects of changing the flux carrying component to pressed SMC parts is
investigate based on a comprehensive understanding of the properties of the material. A 3-D finite-element analysis is
performed for accurate parameter calculation. To validate the simulation, a new static test measurement was fully
conducted on a prototype motor and the results agree with the theoretical calculations and old measured static test.
Hybrid Electric Aircraft Propulsion Motor
Nicola Chiodetta
Moving to Hybrid Electric Aircraft Propulsion is now being recognised as a major option to provide more
environmentally friendly air travel. Maximum exploitation of existing gas turbines technology has already been
reached, and no significant further development is forecasted. Latest models for electrical solutions suggest up to 75%
fuel (CO2) savings with corresponding gains in NOx and noise emissions. Multiple propulsion configurations have
been proposed, among which the BLI (Boundary Layer Ingestion), that this project will aim to design a propulsion
motor for.
Since airplanes will need to fly by means of electrical propulsion rather than continue to exploit conventional turbo
engines, electrical machines design must achieve extremely high power densities. Novel configurations need to be
studied, as no existing electrical machine can reach the performance required by the aerospace sector: at least 20
kW/kg. High speeds/high power solutions with particular attention on the cooling side will be investigated.
Energy storage in the context of smart grids
Nikolas Spiliopoulos , Phil Taylor, Neal Wade and Damian Giaouris
The concept of energy storage in the context of smart grids is investigated. Part of the research is focused on EVs and
particularly in Vehicle - to - Grid (V2G) technology. More precisely, the potential benefits that an EV owner could gain
for providing particular services are examined. One scenario evaluates the use of vehicle, for providing energy to the
home of the owner (Vehicle-to-Home concept). Moreover, other aspects of energy storage concept are going to be
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evaluated in the context of battery degradation and renewable energy integration. In addition smart techniques, such as
Demand –Side Management (DSM) could be correlated as well, by investigating the benefits for the grid and the
customers. A challenging issue, will be to evaluate how DSM could compromise customer’s comfort and give solutions
towards this direction.
Control of the Linear Electric Machines in a Free Piston Engine
Timothy D. Scott
Free Piston Engine (FPE) technology promises the prospect of higher efficiency, lower emission, fuel flexible
combustion engines. Coupled to a linear electric generator, Free Piston Engines are an attractive possibility for future
range extender technology in series hybrid electric vehicles. However as purely linear machines, with their motion
ungoverned by a crankshaft, challenges remain with the degree of control needed to keep Free Piston Engines operating
in a safe, reliable and efficient manner. These have to be addressed before commercial FPE technology will become
widely available. This presentation identifies these challenges and looks at how they might be addressed. In particular it
studies the issues around the control of the linear electric machine, used both as a starter and a generator within these
engines.
A Comprehensive Comparison in a Dynamic Electric Vehicle Charging System
Van-Binh Vu, Mohamed Dahidah and Volker Pickert
Electric vehicle technology has been intensively developed as an attempt to reduce carbon-dioxide emissions caused by
internal combustion engines in conventional vehicles. EVs in general are equipped with expensive on-board energy
storage (batteries) and power electronics for charging and discharging the battery. The main issue is that batteries take
up large space and weight portion in vehicles, and require frequent and long hour charging time for short driving range.
These problems are not easily solved by current battery technology, which currently affects the number of EVs
distributed in the market at present. In recent times, wireless power charging (WPC) of electric vehicles (EVs) has
gained huge attractions. To reduce the cost, size, weight, and volume of batteries and on-board chargers, the concept of
dynamic EV charging (DEVC) adopting WPC has been proposed. With this system, electric vehicles can be charged
wirelessly while moving on the road. A DEVC system can be classified as long-track transmitter and short-individual
transmitters. In this research, a comprehensive comparison between two kinds of transmitters in a DEVC system
illustrating with some simulation results is presented.
Sizing of Hybrid Renewable Systems with Energy for the Isle of Wight
Yarah Jamil Khawaja , Damian Giaouris, Haris Patsios and Mohamed Dahidah
This research aims to find the optimal sizing for a hybrid renewable energy system with energy storage for the Isle of
Wight, the main objective is to develop an optimization method to size the components of HRES with ESS to be applied
on the Isle of Wight, and perform a reliability and cost analysis in order to reach the optimum HRES with minimum
costs. The IOW project targets to decarbonise the electricity system of the island to make it self-sufficient in energy
from renewables. An analytical method will be applied on the distribution network of the Isle of Wight for limiting
import energy from the main grid. A various group of simulations have been executed on Matlab by implementing an
analytical method to find the adequate sizing of ESS. Three case studies were analysed based on three areas on the Isle
of Wight and they are: Cowes, Freshwater, and Newport. The results shows the power rating of the ESSs for the three
cases equal to the maximum load in that area, while the energy capacity of them increase with the load increasing.