eee questions anna university chennai

7/22/2019 EEE questions anna university Chennai

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EE1353POWER ELECTRONICSUNIT-I

(POWER SEMICONDUCTOR DEVICES)PART-A

1. What are the different methods to turn on the thyristor?

2. Define latching current.3. Define holding current.4. What is a snubber circuit?5. Why IGBT is very popular nowadays?6. What is the difference between power diode and signal diode?7. What are the advantages of GTO over SCR?8. What losses occur in a thyristor during working conditions?

PART-B1. Draw the two transistor model of SCR and derive an expression for anodecurrent. (8)2. Explain the characteristics of SCR (8)

3. Describe the various methods of thyristor turn on. (16)4. Explain the operation of MOSFET and IGBT (16)

UNIT II (PHASE-CONTROLLED CONVERTERS)PART-A

1. What is the function of freewheeling diodes in controlled rectifier?2. What is commutation angle or overlap angle?3. What are the advantages of six pulse converter?4. What is meant by commutation?5. What are the types of commutation?6. Mention some of the applications of controlled rectifier.7. What are the different methods of firing circuits for line commutated converter?

8. What is meant by natural commutation?9. What is meant by forced commutation? In this commutation, the currentflowing through

PART-BKINGS COLLEGE OF ENGINEERING, PUNALKULAM1. Describe the working of 1_ fully controlled bridge converter in the Rectifyingmode and inversion mode. And derive the expressions for average outputvoltage and rms output voltage. (16)2. Describe the working of 3_ fully controlled bridge converter in the Rectifyingmode and inversion mode. And derive the expressions for average outputvoltage and rms output voltage. (16)

3. Describe the working of Dual converter. (16)4. Derive the expressions for average output voltage and rms output voltageof 1_ semiconverter. (16)

UNIT III (DC TO DC CONVERTERS)PART-A

1. What is meant by dc chopper?2. What are the applications of dc chopper?3. What are the advantages of dc chopper?


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4. What is meant by step-up and step-down chopper?5. What is meant by duty-cycle?6. What are the two types of control strategies?7. What is meant by TRC?8. What are the two types of TRC?

9. What is meant by PWM control in dc chopper?PART-B1. Describe the principle of step-up chopper. Derive an expression for theaverage output voltage in terms of input dc voltage & duty cycle. (16)2. Describe the working of four quadrant chopper. (16)3. Explain the working of current commutated chopper with aid of circuit diagramand necessary waveforms. Derive an expression for its output voltage. (16)4. Explain the working of voltage commutated chopper with aid of circuit diagramand necessary waveforms. Derive an expression for its output voltage. (16)

UNIT IV (INVERTERS)PART-A

1. What is meant by inverter?2. What are the applications of an inverter?3. What are the main classification of inverter?4. Why thyristors are not preferred for inverters?5. Give two advantages of CSI.6. What is meant a series inverter?7. What is meant a parallel inverter?8. What are the applications of a series inverter?9. What is meant by McMurray inverter?10. What are the applications of a CSI?11. What is meant by PWM control?

12. What are the advantages of PWM control?PART-B1. Describe the operation of series inverter with aid of diagrams. Describe anexpression for output frequency, current and voltages. What are thedisadvantages of basic series inverter? (16)2. State different methods of voltage control inverters. Describe about PWMcontrol in inverter. (16)3. Explain the operation of 3_ bridge inverter for 180 degree mode of operationwith aid of relevant phase and line voltage waveforms. (16)

UNIT V (AC VOLTAGE CONTROLLER)PART-A

1. What does ac voltage controller mean?2. What are the applications of ac voltage controllers?3. What are the advantages of ac voltage controllers?4. What are the disadvantages of ac voltage controllers?5. What are the two methods of control in ac voltage controllers?6. What is the difference between ON-OFF control and phase control?7. What is meant by cyclo-converter?8. What are the two types of cyclo-converters?


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9. What is meant by step-up cyclo-converters?10. What is meant by step-down cyclo-converters?11. What are the applications of cyclo-converter?

PART-B1. Explain the operation of multistage control of AC voltage controllers with neat

diagram. (16)2. Explain the operation of 1_ AC voltage controller with RL load. (16)3. Explain the operation of 1_ sinusoidal AC voltage controller. (16)4. For a 1_ voltage controller, feeding a resistive load, draw the waveforms ofsource voltage, gating signals, output voltage and voltage across the SCR.Describe the working with reference to waveforms drawn. (16)


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EE 1352 - ELECTRICAL MACHINE DESIGNUNIT I

FUNDAMENTAL CONCEPTSPart A (2 MARKS)

1. What are the main dimensions of a rotating machine?

2. Define gap contraction factor for slots.3. Define total gap contraction factor.4. What is Carters Co-efficient? What is its usefulness in the design of dc machine?5. What is the effect of salient poles on the air gap mmf?6. Define Field form factor.7. List the methods used for estimating the mmf for tapered teeth.8. What is real and apparent flux density?9. In which way the air gap length influence the design of machines?10. What is magnetic leakage and leakage co-efficient?11. What is fringing flux?12. What are the differences between leakage flux and fringing flux?13. What is magnetic circuit and what are its constituents.14. Define gap contraction factor for ducts.15. What is tooth top leakage flux?16. What is ZigZag leakage flux?17. What is skew leakage flux?18. How will you minimize the leakage flux?19. Define slot space factor.20. Discuss the parameters governing the selection of conductor dimensions.

Part B (16 MARKS)1. a) Discuss in detail about the cooling methods adopted in transformers. (10)b) What are the advantages of hydrogen as a better cooling medium for turboalternators? (6)

2. a) Discuss about the various types of thermal ratings of the electrical machines(10)b) Discuss about the various Insulating materials and their grades. (6)3. a) Explain in detail about the MMF calculation for tapered Teeth. (10)b) Discuss in detail about the real and apparent flux densities. (6)4. a) Write about specific magnetic loading and specific electric loading. (8)b) Explain about the cooling of Turbo alternators. (8)5. a) What are the direct and indirect cooling methods used in electricalmachines (8)b) Derive an equation for the slot leakage reactance (8)6. a) Discuss in detail about the unbalance magnetic pull. (8)b) Explain about the air gap reluctances in different types of armature slots (8)

UNIT IIDC MACHINES

Part A (2 MARKS)1. Define specific magnetic loading.2. Define specific electric loading.3. What is output equation?4. Write the expressions for output coefficients5. List the factors that influence the separation of D and L of a dc machine.


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6. What is square pole criterion?7. List the various L/_ ratios used for separation of D and L in induction motor.8. In a dc machine what are the limiting values of armature diameter?9. What is un-balanced magnetic pull and how its ill-effects can be overcome?10. What are the factors that affect the size of rotating machines?11. What are the factors that decide the choice of specific magnetic loading?12. .What are the factors that decide the choice of specific electric loading?13. What is magnetization curve?14. What are the factors that modify the reluctance of air gap15. What are the problems encountered in estimating the mmf for teeth?16. What factor decides the number of turns in a winding?17. How the area of cross-section of a conductor is estimated?18. What are the ranges of specific magnetic loading and specific electric loading in dcmachine?19. What are the factors to be considered for the selection of number of poles in a dcmachine?20. What are the parameters that are affected by the number of poles?

21. List the advantages and disadvantages of large number of poles.22. Why square pole is preferred?23. State the difference between the armature winding of dc machine and the statorwinding of ac machine.24. Define winding pitch.25. What is back pitch?26. What is front pitch?27. Define commutator pitch.28. What is equalizer connection?29. What are the factors to be considered for estimating the length of air gap in dcmachines?30. What are the effects of armature reaction?

31. How the polarities of inter pole are decided.32. What is the effect of interpole on main pole?33. What is the fundamental requirement of a good insulating material?34. What is the importance of temperature as a factor in the life of insulatingmaterials?35. Why mineral insulating oils are the most widely used liquid insulation.36. Why large size machines have large rating time constant?37. Why ac armature winding is always made short-pitched.38. Why equalizer connections are necessary for the armature winding of a dc machinewith lap winding.39. Why the voltage wave form of an ac armature winding contains harmonics. ?

40. Why the conductor eddy current loss increases if embedded deeper in the slot.Part B (16 MARKS)1. a) A 4 pole, 25 HP, 500 V, 600 rpm series motor has an efficiency of 82%.The pole faces are square and the ratio of pole arc to pole pitch is 0.67.Take Bav = 0.58 Wb/m2 and ac = 17000 amp.cond/m. Obtain the maindimensions of the core. (12)b) Enumerate the procedure for shunt field design (4)2. a) A 4 pole, 400 V, 960 rpm, shunt motor has an armature of 0.3 m in diameter and


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0.2 m in length. The commutator diameter is 0.22 m. Give full details of asuitable winding including the number of slots, number of commutator segmentsand number of conductors in each slot for an average flux density ofapproximately 0.55wb/m2Wb / m2 in the air gap. (12)b) Find the main dimension and number of poles of a 37 kW, 230V, 1400 rpm,shunt motor so that a square pole face is obtained. The average gap density is0.5 wb/m2 and the ampere conductors / meter are 22000. The ratioof pole arc to pole pitch is 0.7 and the full load efficiency is 90% (4)3. i) Derive the out put equation of a DC machine. (10)ii) Distinguish between lap winding and wave winding. (6)4. i) Determine the total commutator losses for a 1000kw, 500V, 800rpm, 10 polesgenerator. Given that commutator diameter is 1.0m, current density at brushcontact =75x10-3 A/mm2 brush pressure = 14.7kv/ m2, co efficiency offriction = 0.28, brush contact drop= 2.2V. (10)ii) Discuss the significance of specific loadings in the design of DC machines. (6)5. i) Design a suitable commutator for a 350kw, 600rpm, 440V, 6poles DC generatorhaving an armature diameter of 0.75m. The number of slots is 288. Assume

suitable values where its necessary? (10)ii) Discuss the choice of poles and speed in DC machine. (6)6. i) List out the procedure involved in design of shunt field winding and series fieldwinding? (10)ii) Find the main dimension and number of poles of a 37 kW, 230V, 1400 rpm,shunt generator so that a square pole face is obtained. The average gapdensity is 0.7 wb/m2 and the ampere conductors / meter are 25000. The ratio ofpole arc to pole pitch is 0.7 and the full load efficiency is 90 % (6)7. Determine the shunt field winding of a 6-pole, 440V, dc generator allowing a dropof 15 % in the regulator. The following design date are available, mmf per pole =7200 AT; mean length of turn = 1.2 m; winding depth = 3.5 cm; watts per sq.cm. ofcooling surface = 650. Calculate the inner, outer and end surfaces of the

cylindrical field coil for cooling. Take diameter of the insulated wire to be 0.4 mmgreater than the bare wire. Assume 2 microohm / cm as the resistivity of copperat the working temperature. (16)8. Determine the diameter and length of armature core for a 55kW, 110V, 1000 rpm,4 pole shunt generator, assuming specific electric and magnetic loadings of26000 amp.cond. / m and 0.5 Wb / m2 respectively. The pole arc should be about70% of pole pitch and length of core about 1.1 times the pole arc. Allow 10ampere for the field current and assume a voltage drop of 4 volts for thearmature circuit. Specify the winding to be used and also determine suitablevalues for the number of armature conductors and slots. (16)

UNIT III

TRANSFORMERSPart A (2 MARKS)

1. What is the cause of noise in transformer?2. Why the area of yoke in a transformer is kept 15-20% more than that of core?3. What are the salient features of a distribution transformer?4. In transformers, why the low voltage winding is placed near the core?5. Why circular coils are preferred in transformers?6. What are the advantages and disadvantages of stepped cores?


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7. What do you mean by stacking factor? What is its usual value?8. What is tertiary winding?9. List the different methods of cooling of transformers.10. How the heat dissipation is improved by the provision of cooling tubes?11. In mines applications transformer with oil cooling should not be used why?12. What are the important properties of steel used in transformer core?13. What are the advantages and disadvantages of using higher flux density in the core?14. Why the cross section of yoke is taken greater than core section.15. What are the types of windings, commonly used for LV winding.16. What are the draw backs of sandwich winding?17. Name a few insulating materials that are used in transformers.18. How iron losses occurring in transformers can be minimized.19. Mention clearly the condition for maximum efficiency for a transformer20. Why the efficiency of a transformer is so high?21. Mention the main function of cooling medium used in transformers.

Part B (16 MARKS)

1. i) Estimate the main dimensions including winding conductor area of a 3 phase

delta-star core type transformer rated at 300KVA, 6600/400 V, 50 Hz. A suitablecore with 3 steps having a circumscribing circle of 0.25m diameter and leg spacingof 0.4 m is available. EMF / turn = 8.5 V,_ = 2.5 A /mm2, kw= 0.28 and Sf = 0.9(stacking factor) (10)ii) Derive the output equation of a single phase transformer. (6)2. i) Determine the main dimensions of the core, the number of turns, the crosssectional area of conductors in primary and secondary windings of a 100 kVA, 2200

/ 480 V, 1-phase, core type transformer, to operate at a frequency of 50 Hz, byassuming the following data. Approximate volt per turn = 7.5 volt. Maximum fluxdensity = 1.2 Wb / m2. ratio of effective crosssectional area of core to square ofdiameter of circumscribing circle is 0.6. Ratio of height to width of window is 2.Window space factor = 0.28. Current density = 2.5 A/mm2. (10)ii) Explain how to estimate the no-load current of a three phase transformer. (6)3. i) A 250 kVA, 6600 / 400 V, 3-phase core type transformer has a total loss of 4800watts on full load. The transformer tank is 1.25 m in height and 1 m x 0.5 m in plan.Design a suitable scheme for cooling tubes if the average temperature rise is to belimited to 35C. The diameter of the tube is 50 mm and are spaced 75 mm fromeach other. The average height of the tube is 1.05 m. (10)ii) Describe about the effect of frequency on Iron losses. (6)4. i) Derive the voltage per turn equation of a transformer. (8)ii) Discuss about the various methods of cooling of power transformer. (8)5. i) Determine the core and yoke dimensions for a 250 kVA, 50Hz, single phase, coretype transformer, Emf per turn = 12 V, the window space factor = 0.33, current

density = 3A / mm2 and Bmax = 1.1 T. The distance between the centers of thesquare section core is twice the width of the core. (6)ii) Calculate the dimensions of the core, the number of turns and cross sectionalarea of conductors in the primary and secondary windings of a 250 kVA, 6600 / 400V, 50 Hz, single phase shell type transformer. Ratio of magnetic to electric loadings= 560 x 10-8, Bm = 1.1 T,_ = 2.5 A / mm2, Kw = 0.32, Depth of stacked core / widthof central limb = 2.6; height of window / width of window = 2.0. (10)6. i) A 375 kVA, single phase core type transformer operating on 6.6 kV / 415V is to be


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designed with approximately 7.5V per turn and a flux density of 1.1 T. Design asuitable core section and yoke section using two sizes of stampings. The width ofsmaller stampings may be approximately 0.62 times the larger stampings. State theassumptions made. (6)ii) The tank of a 500 kVA, 50Hz, 1-phase, core type transformer is 1.05 x 0.62 x 1.6m high. The mean temperature rise is limited to 35C. The loss dissipating surfaceof tank is 5.34 m2. Total loss is 5325 W. Find the area of tubes and number of tubesneeded. (10)7. The tank of 1250 kVA, natural oil cooled transformer has the dimensions length,width and height as 0.65 x 1.55 x 1.85 m respectively. The full load loss = 13.1 kW,loss dissipation due to radiations = 6 W / m2-C, loss dissipation due to convection =6.5 W / m2C, improvement in convection due to provision of tubes = 40%,temperature rise = 40C, length of each tube = 1m, diameter of tube = 50mm. Findthe number of tubes for this transformer. Neglect the top and bottom surface of thetank as regards the cooling. (16)

UNIT IVTHREE PHASE INDUCTION MOTORS

Part-A (2 marks)1. Why does induction motor designed with high specific electric loadings have smallerover load capacity?2. Why the harmonic leakage flux in squirrel cage induction rotor is not present?3. Why the length of air gap in induction motor is kept minimum possible?4. Why do die-cast rotors is extensively used in making 3 phase cage induction motor?5. Why do 3 phase squirrel cage induction motor finds wide application in industry?6. What is hot spot temperature?7. What is the advantage of having wound rotor construction?8. What is rotating transformer?9. What is integral slot winding and fractional slot winding?

10. What types of slots are preferred in induction motor?11. List the undesirable effects produced by certain combination of rotor and stator slots.12. What are the advantage and disadvantage of large air gap length in induction motor?13. What are the factors which influence the power factor of an induction motor?14. What are the criteria used for the choice for number of slots of an induction machine?15. What are the factors to be considered for estimating the length of air gap in inductionmotor?16. List out the methods to improve the power factor of an induction motor?17. Why the air gap of an induction motor is made as small as possible?18. What happens if the air-gap of an induction motor is doubled?19. What is the condition for obtaining the maximum torque in case of 3 phase inductionmotor?

20. What are the special features of the cage rotor on induction machine?.

Part-B (16 Marks)1. Estimate the main dimension, air gap length, stator slots, slots / phase and crosssectional area of stator and rotor conductors for three phase, 15HP, 400V, 6 pole,50Hz, 975 rpm induction motor. The motor is suitable for stardelta starting. Bav= 0.45 wb/m2. ac = 20000 AC/m. L /_ = 0.85._ = 0.9 , P.F = 0.85. (16)2. A 15 kW, three phase, 6 pole, 50 Hz, squirrel cage induction motor has the


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following data, stator bore dia = 0.32m, axial length of stator core = 0.125 m,number of stator slots = 54, number of conductor / stator slot = 24, current in eachstator conductor = 17.5 A, full load P.F = 0.85 lag. Design a suitable cage rotorgiving number of rotor slots section of each bar and section of each ring. The fullspeed is to be 950 rpm, use copper for rotor bar and end ring conductor.Resistivity of copper is 0.02_m. (16)3. A 90 kW, 500V, 50 Hz, three phase, 8 pole induction motor has a star connectedstator winding accommodated is 63 slots with a 6 conductors / slot. If slip ringvoltage, an open circuit is to be about 400V at no load find suitable rotor winding.Calculate number of rotor slots, number conductors / slot, coil span, number ofslots per pole. P.F = 0.9 and the efficiency is 0.85 (16)4. Determine the approximate diameter and length of stator core, the number ofstator slots and the number of conductors for a 20 kW, 400V, 3 phase, 4pole,1200rpm, delta connected induction motor. Bav =0.5T,_ = 0.82, ac = 26,000amp.cond/m, power factor = 0.8, L/_ = 1, double layer stator winding. (16)5.6. Estimate the main dimensions, air-gap length, stator slots, stator turns per phase

and cross sectional area of stator and rotor conductors for 3 phase, 110 kW,3300V, 50 Hz, 10 poles, 600 rpm, Y connected induction motor, Bav = 0.48 Wb/m2,ac = 28,000 amp.cond/m, L/_ = 1.25, _ = 0.9, power factor = 0.86. (16)7. Design a cage rotor for a 18.8HP, 3phase, 440V, 50Hz, 1000rpm, induction motorhaving full load efficiency of 0.86, power factor = 0.86, D=0.25m, L=0.14m, Zss/Ss=54. Assume missing data if any. (16)

UNIT VSYNCHRONOUS MACHINES

Part A (2 MARKS)1. State three important features of turbo alternator rotors.2. Why salient pole construction is rejected for high speed alternators.

3. What material user for the construction of turbo alternator rotor.4. What is run-away speed?5. What is approximately the run away speed of Kaplan turbine.6. Write the expression for the output coefficient of synchronous machine.7. What are the advantages of designing the alternators with higher flux density?.8. What are the disadvantages of designing the alternators with higher gap flux density?9. Why semi- closed slots are generally preferred for the stator of induction motors.10. What is the effect of specific magnetic loading on the size of the machine?11. What is the effect of specific electric loading on t he copper losses?12. Write down the main consideration in the selection of specific loadings for the designof induction motor.13. What is critical speed of alternator?

14. What are the functions of damper winding?15. What is Short Circuit Ratio (SCR)?16 What is the effect of SCR on synchronous machine performance?17. Why it is necessary to cool an electrical machine?18. What is limiting factor for the diameter of synchronous machine?19. Discuss how ventilation and cooling of a large high speed alternator is carried out.20. Mention the factors to be considered for the design of field system in alternator.

Part B (16 Marks)


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1. Determine the main dimension for 1000 kVA, 50 Hz, three phase, 375 rpm alternator.The average air gap flux density = 0.55 wb/m2 and ampere conductors / m = 28000.Use rectangular pole. Assume a suitable value for L /_ in order that bolted on poleconstruction is used for which machine permissible peripheral speed is 50 m/s. Therunway speed is 1:8 times synchronous speed. (16)2. Find main dimension of 100 MVA, 11 kV, 50 Hz, 150 rpm, three phase water wheelgenerator. The average gap density = 0.65 wb/m2 and ampere conductors / m are40000. The peripheral speed should not exceed 65 m/s at normal running speed inorder to limit runaway peripheral speed. (16)3. Determine suitable number of slots conductors / slot for stator winding of three phase,3300V, 50 Hz, 300 rpm alternator, the diameter is 2.3m and axial length of core =0.35 m. Maximum flux density in air gap should be approximately 0.9 wb / m2.Assume sinusoidal flux distribution use single layer winding and star connection foestator. (16)4. Determine for 500kVA, 6600V, 20Hz, 500 rpm and connected three phase salientpole machine diameter, core length for square pole face number of stator slots andnumber of stator conductors for double layer winding. Assume specific magnetic

loading = 0.68 tesla, ac = 30000 AC/m and Kws = 0.955. (16)5. A 1000 kVA, 3300V, 50Hz, 300 rpm, three phase alternator has 180 slots with 5conductors / slot ,single layer winding with full pitch coil is used. The winding is starconnected with one circuit / phase. Determine specific electric loading and magneticloading, IF stator core is 0.2 m and core length = 0.4 m. Using same loadingdetermine the data for 1250 kVA, 3300V, 50 Hz, 250 rpm, three phase star connectedalternator having 2 circuits / phase. (16)6. Determine for a 15 MVA, 11kV, 50 Hz, 2pole, star connected turbo alternator (i) airgapdiameter, (ii) core length, (iii) number of stator conductors, from the given dataBav= 0.55 Wb/m2, ac = 36000 amp.cond/m,_ = 5A/mm2, synchronous speed ns = 50rps, Kws = 0.98, peripheral speed = 160 m/s. (16)OTHER IMPORTANT QUESTIONS

1. Discuss the requirements of high conductivity materials.2. Write notes on temperature gradient in conductors placed in slots, with the help ofequations3. Writes notes on classification of insulating materials.4. Derive the voltage per turn equation for a single phase transformer.5. Derive an expression to find the specific slot permeance of a fully opened rectangularslot.6. What are the various types of synchronous machines based on rotor construction?Bring out the constructional differences between them.7. Discuss the effects of short circuit ratio on the performance of a synchronous machine.8. Explain the concept of determining the temperature gradients in conductors placed in

slots9. What are the limitations of design of electrical apparatus? Explain them.10. Explain the various factors that affected by the selection of number of poles in DCmachines.11. Explain the design of rotor bars and slots.12. Explain the choice of specific magnetic and electric loadings of synchronousmachines.13. Explain the design of induction motors using circle diagram.


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14.i Discuss the factors that influence the choice of number of poles o f a dc machineii.Design a shunt field coil of a dc motor from the following data.Field ampere turns/pole=9000, Mean length of turn=1.4 m, Depth of coil=35*10-3mVoltage across field coil=40V, Receptivity of wire=0.021 ohm/m and mm2.Thickness of insulating varnish=0.2mm, Power dissipation from total surface of thecoil


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conductors per slot 30, rotor slots 53, one bar per rotor slot, length of each bar 12cm, area of bar 0.6220cm2, mean diameter of end rings 18cm, area of ring 1.5cm2.Full pitch winding with phase spread for stator. Specific resistance is 0.021_/mlength per mm area.21. i. Prove that with usual notations that the KVA rating o f a synchronous generatoris given by the following relation. KVA=1.11 Kw Bav ac L Va *10-3Where Va= peripheral speed in m/secii. Design suitable values of diameter and length of a 75 MVA, 11KV, 50 Hz,3000rpm, 3phase, star connected alternator. Also determine the value of flux,conductor/slot, number of turns/phase and size of alternator conductor.Given: Average gap density=0.6 Tesla, Ampere cond/m=50000, Peripheral speed= 180 m/sec, Winding factor=0.95, Current density=6A/mm222. A 1250 KVA, 3 phase, 6600V salient pole alternator has the following data.Air gap diameter= 1.6m, length of core=0.45m, number of poles=20, armatureampere conductors per meter=28000, ratio of pole pitch=28mm, current density indamper bars 3A/mm2. Design a suitable damper winding for the machine.


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POWER SYSTEM ANALYSIS

QUESTION BANKUNITI THE POWER SYSTEMAN OVERVIEW AND MODELLING

PARTA(TWO MARK QUESTIONS)

1.What is a single line diagram?

2.A generator rated at 30 MVA, 11 kV has a reactance of 20%. Calculate its per unit reactance

for a base of 50 MVA and 10 kV

3.Define per unit value.

4.Draw equivalent circuit of a transformer.

5.Write the equation for per unit impedance.

6.Represent a short transmission line of 3 phase into its equivalent single phase circuit.

7.Write any two advantages of per-unit representation.

8.What is the need for system analysis in planning and operation of power system?

9.How is generator in transient analysis represented?

10.What are the advantages of per unit system?

11.List the different components of power system.

12.What is a bus?

13.What are the approximations made in reactance diagram?

14.How are the base values chosen in per unit representation of a power system?

15.Write the equation converting the p.u. impedance expressed in one base to another base.

16.What is bus impedance matrix?

17.Define primitive matrix.

PARTB

1. Draw the reactance diagram for the power system shown in Fig.1. Neglect resistance and

use a base of 100 MVA, 220 kV in 50 line. The ratings of the generator, motor and

transformer are given below.

Generator: 40 MVA, 25 kV, X = 20%

Synchronous motor : 50 MVA, 11 kV, X = 30%

YY Transformer : 40 MVA, 33/220 kV, X = 15%

Y - 30 MVA, 11/220 kV, (/Y), X = 15% (16)


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2. Draw the structure of an electrical power system and describe the components of the system

with typical values (16)

3. Obtain the per unit impedance (reactance) diagram of the power system shown in Fig.3

Fig. 3

One-line representation of a simple power system.

Generator No. 1: 30 MVA, 10.5 kV, X = 1.6 Ohm



Transformer T1 (3phase) : 15 MVA, 33/11 kV, X = 15.2 Ohm per phase on HT side

Transformer T2 (3phase) : 15 MVA, 33/6.2 kV, X = 16 Ohm per phase on HT side

Transmission line : 20.5 Ohm/phase

Load A : 15 MW, 11kV, 0.9 p.f. lagging

Load B : 40 MW, 6.6 kV, 0.85 lagging p.f. (16)

4. Explain the modeling of generator, load, transmission line and transformer for power flow,

short circuit and stability studies. (16)

5. Choosing a common base of 20 MVA, compute the per unit impedance (reactance) of the

components of the power system shown in Fig.5 and draw the positive sequence

impedance (reactance) diagram.

Fig. 5

Gen 1 : 20 MVA, 10.5 kV, X = 1.4 Ohm

Gen 2 : 10 MVA, 6.6 kV, X = 1.2 OhmTr 1 : 10 MVA, 33/11 kV, X = 15.2 Ohm per phase on HT side

Tr 2 : 10 MVA, 33/6.2 kV, X = 16.0 Ohm per phase on HT side

Transmission line : 22.5 Ohms per phase (16)

6. Draw the reactance diagram using base of 100 MVA, 220 kV in 50 line.

Generator : 40 MVA, 25 kV,, X = 20%

Synchronous motor : 50 MVA, 11 kv, X = 30%

Star-Star transformer : 40 MVA, 33/220 kV, X = 15%

Star-delta transformer : 30 MVA, 11/220 kV, X = 15%. (16)

7. (i) What are the step by step procedures to be followed to find the per-unit impedance

diagram of a power system? (4)

(ii) Draw the structure of an electrical power system and describe the components of the

system with typical values. (12)

8. Write short notes on:


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9.

What are the constraints to be satisfied to solve load flow equation for a given bus load

configuration?

10. What technique is used to solve load flow problems using Zbus (Bus impedance matrix)?

11. Define load bus.

12. What are the disadvantages in reactive power compensation by shunt capacitors and how it

can be overcome?

13. What is off-nominal transformer ratio?

14. What is regulating Transformer and boosting Transformer?

15. How a load flow study is performed?

16. Compare Gauss-Seidel method, Newton-Raphson method and FDPF method with respect

to number of iteration taken for convergence and memory requirements.

PARTB

1. Derive load flow algorithm using GaussSeidel method with flow chart and discuss the

advantages of the method. (16)

2. Derive load flow algorithm using Newton-Raphson method with flow chart and state the

importance of the method. (16)

3. Explain clearly the algorithmic steps for solving load flow equation using NewtonRaphson

method (polar form) when the system contains all types of buses. Assume that the generators at

the P-V buses have adequate Q Limits. (16)

4. Explain the step by step procedure for the NR method of load flow studies. (16)

5. Find the bus admittance matrix for the given network. Determine the reduced admittance

matrix by eliminating node 4. The values are marked in p.u. (16) KINGS COLLEGE OF

ENGINEERING, PUNALKULAM 4


6. Find the bus impedance matrix for the system whose reactance diagram is shown in fig. All

the impedances are in p,u. (16)

7. (i) Derive the power flow equation in polar form. (8)

(ii)Write the advantages and disadvantages of Gauss-Seidel method andNewton-Raphson method. (8)

8.

Explain the step by step computational procedure for the Gauss-Seidel

method of load flow studies. (16)

9. The parameters of a 4-bus system are as under:


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Bus code Line impedance Charging admittance(pu) (pu)

1-2 0.2 + j 0.8 j 0.02

2-3 0.3 + j 0.9 j 0.03

2-4 0.25 +j 1.0 j 0.04

3-4 0.2 + j 0.8 j 0.02

1-3 0.1 + j0.4 j 0.01

Draw the network and find bus admittance matrix. (16)

10. Explain the step by step computational procedure for the Gauss-Seidel method of load flow

studies. (16)

11. With a flow chart, explain the NR Iterative method for solving load flow problem. (16)

12. (i) Compare Gauss-Seidel method and Newton-Raphson method of load flow studies (6)

(ii) Fig.12 shows a three bus power system.

Bus 1 : Slack bus, V= 1.05/00 p.u.

Bus 2 : PV bus, V = 1.0 p.u. Pg = 3 p.u.

Bus 3 : PQ bus, Pl = 4 p.u., Ql = 2 p.u.

Carry out one iteration of load flow solution by Gauss Seidel method.

Neglect limits on reactive power generation. (10) KINGS COLLEGE OF ENGINEERING,

PUNALKULAM 5


UNITIII - SYMMETRICAL FAULT ANALYSIS

PART- A

1.

Write the relative frequency of occurrence of various types of faults.

2.

Find the fault current in Fig.2, if the pre-fault voltage at the fault point is 0.97 p.u.?

Fig .2

3.

What are the assumptions made in short circuit studies of a large power system network?

4.

What are the reactance used in the analysis of symmetrical faults on the synchronous machines

as its equivalent reactance?

5.

What is the reason for Transients during short circuits?

6.


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Define short circuit MVA.

7.

How do short circuits occur in a power system?

8.

Mention two objectives of short circuit analysis.

9.

What is short circuit capacity of a network bus? Define the same.

10.

List the various types of shunt faults.

11.

What is the need for short circuit analysis?

PARTB

1. A generator is connected through a transformer to a synchronous motor the sub transient

reactance of generator and motor are 0.15 p.u. and 0.35 p.u. respectively. The leakage

reactance of the transformer is 0.1 p.u. All the reactances are calculated on a common base. A

three phase fault occurs at the terminals of the motor when the terminal voltage of the generator

is 0.9 p.u. The output current of generator is 1 p.u. and 0.8 p.f. leading. Find the sub transient

current in p.u. in the fault, generator and motor. Use the terminal voltage of generator as

reference vector. (16)

2. Explain the step by step procedure for systematic fault analysis using bus impedance matrix.

(16)

3. A 60 MVA, Y connected 11 KV synchronous generator is connected to a 60 MVA, 11/132 KV

/Y transformer. The sub transient reactance Xd of the generator is 0.12 p.u. on a 60 MVA

base, while the transformer reactance is 0.1 p.u. on the same base. The generator is unloaded

when a symmetrical fault is suddenly placed at point p as shown in Fig. 3 Find the sub transient

symmetrical fault current in p.u. amperes and actual amperes on both side of the transformer.

Phase to neutral voltage of the generator at no load is 1.0 p.u. (16)

KINGS COLLEGE OF ENGINEERING, PUNALKULAM 6

POWER SYSTEM ANALYSISFig. 3

4. A threephase transmission line operating at 33 KV and having a resistance and reactance

of 5 Ohms and 15 Ohms respectively is connected to the generating station bus-bar through a

5000 KVA step up transformer which has a reactance of 0.05 p.u. Connected to the bus-bars

are two alternators, are 10,000 KVA having 0.08 p.u. reactance and another 5000 KVA having


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0.06 p.u. reactance. Calculate the KVA at a short circuit fault between phases occurring at the

high voltage terminals of the transformers. (16)

5. A synchronous generator and a synchronous motor each rated 25 MVA, 11 KV having 15%

sub-transient reactance are connected through transformers and a line as shown in fig. The

transformers are rated 25 MVA< 11/66 KV and 66/11 KV with leakage reactance of 10% each.

The line has a reactance of 10% on a base of 25 MVA, 66 Kv. The motor is drawing 15 MW at

0.5 power factor leading and a terminal voltage of 10.6 KV. When a symmetrical 3 phase fault

occurs at the motor terminals. Find the sub-transient current in the generator, motor and fault.

(16)

6. A three phase power of 700 MW is to be transmitted to a substation located 315 kM from the

source of power. For a preliminary line design assume the following parameters:

Vs = 1.0 p.u., Vr + 0.9 p.u. = 5000 km ; zc = 320 , and = 36.870 .

(i)

Based on the practical line load ability equation, determine a nominal voltage level for

the transmission line. (8)

(ii)

For the transmission voltage level obtained in (i) Calculate the theoretical maximum

power that can be transferred by the transmission line. (8)

7. A 25,000 KVA, 13.8 kV generator with Xd = 15% is connected through a transformer to a

bus which supplies four identical motors as shown in Fig. 7 The sub transient reactance Xd of

each motor is 20% on a base of 5000 KVA, 6.9 kV. The three-phase rating of the transformer is

25,000 KVA, 13.8/6.9 kV, with a leakage reactance of 10%. The bus voltage at the motors is 6.9

kV when a three-phase fault occurs at point p. for the fault specified, determine (i) the sub

transient current in the fault (ii) the sub transient current in breaker A and (iii) the symmetrical

short-circuit interrupting current in the fault and in breaker A. (16)



Fig.7 one line diagram

8

Determine Zbus for the network shown below in Fig. 8 where the impedances labeled 1 through

6 are shown in per unit. Preserve all buses. (16)

Fig. 8Fig. 8 Branch impedances are in p.u. and branch numbers are in parentheses.

8.

With a help of a detailed flowchart, explain how a symmetrical fault can be analyzed using


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Zbus ? (16)

9.

(i) For the radial network shone below a three phase fault occurs at F. Determine the fault

current and the line voltage at 11 kV bus under fault conditions. (6)



(ii) Explain the procedure for making short-circuit studies of a large power system networks

using digital computers. (10)

10.

Two synchronous machines are connected through three phase transformers to the

transmission line shown in Fig.11 the ratings and reactance of the machines and transformers

are

Machine 1 and 2 : 100 MVa, 20kV; Xd = X1 = X2 = 20%X0 = 4%, Xn = 5%

Transformers T1 and T2 : 100 MVA, 20 /345 YkV ; X = 8%.

On a chosen base of 100 MVA, 345 kV in the transmission line circuit the line reactances are X1

= X2 = 15% and X0 = 50%. Draw each of the three sequence networks and find the zero

sequence bus impedance matrixes by means of Zbus building algorithm. (16)

Fig.11



UNITIV - SYMMETRICAL COMPONENTS ANDUNBALANCED FAULT ANALYSIS

PART- A

1.

Draw the equivalent sequence network diagram for a single phase to ground fault in a power

system.

2.

Draw the zero sequence equivalent network diagram for a 3 phase star connected alternator

with reactance earthing.3.

Write the symmetrical components of three phase system.

4.

Draw the equivalent sequence network for a Line-Line bolted fault in a power system.

5.


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What is a sequence network?

6.

What are unsymmetrical faults?

7.

Draw the zero sequence network of a star-connected alternator with zero sequence impedance

zgo when the neutral is grounded through an impedance zn .

8.

Draw the equivalent sequence network diagram for a single phase to ground fault in a power

system.

9.

Compute the following in polar form 0120

1a

i.ja ii. 21aa

10. Draw the zero sequence diagram of a synchronous generator with neutral grounded

11. Draw the negative sequence diagram of a synchronous machine

PART- B

1.

Derive the expression for fault current in Line-to-Line fault on an unloaded generator in terms of

symmetrical components. (16)

2.

Determine the fault current and MVA at faulted bus for a line to ground (solid) fault at bus 4 as

shown in Fig.2

Fig.2

G1, G2 : 100 MVA, 11kV, X+ + X- = 15%, X0 = 5%, Xn = 6%

T1 T2 : 100 MVA, 11kV/220 kV, Xl\leak = 9%

L 1,L2 : X+ = X- = 10%, X0 = 10% on base of 100 MVA. Consider a fault at phase a. (16)



3.

A single line to ground fault occurs on bus 4 of the system shown in Fig.3

(i) Draw the sequence networks and (12)

(ii) Compute the fault current. (4)

Fig. 3

Gen 1 and 2 : 100 MVA, 20kV; X = X 20% ; X0 = 4%; Xn = 5%.

Transformer 1 and 2 : 100 MVA, 20/345 KV; Xleakage = 8% on 100 MVA


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Tr. Line : X = X = 15% X0 = 50% on a base of 100 MVA, 20 kV.

4.. Draw the Zero sequence diagram for the system whose one line diagram is shown in fig.

(16)

5.

Two synchronous machines are connected through three-phase transformers to the

transmission line as given below in Fig. 5. The ratings and reactance of the machines and

transformers are

Machines 1 and 2 : 100 MVA, 20 Kv; Xd = X 1 = X2 = 20%

X0 = 4%; Xn = 5%.

Transformers T1 and T2 : 100 Mva, 20y/345 YkV ; X= 8%

Both transformers are solidly grounded on two sides. On a chosen base of 100 MVA, 345 kV in

the transmission line circuit the line reactance are X1 =X2 = 15% and X0 = 50%. The system is

operating at nominal voltage without prefault currents when a bolted (Zf = o) single line-to-

ground fault occurs on phase A at bus (3) Using the bus impedance matrix for each of the three

sequence networks, determine the sub transient current to ground at the fault. (16)



Fig.5

6.

Determine the positive, negative and zero sequence networks for the system shown in Fig. 6.

Assume zero sequence reactance for the generator and synchronous motors as 0.06 p.u.current limiting reactors of 2.5 are connected in the neutral of the generator and motor No.2

The zero sequence reactance of the transmission line is j 300 . (10)Fig. 6

7.

Develop the connection of sequence network when a line to line fault occurs in a power

network. (16)

8.

Derive the expression for fault current in double line to ground fault on unloaded generator.

Draw an equivalent network showing the inter connection of networks to simulate double line to

ground fault (16)



UNIT- V - POWER SYSTEM STABILITY

PART - A


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1.

On what basis do you conclude that a given synchronous machine has lost stability

2.

Define infinite bus in a power system.

3.

What is power system stability?

4.

State equal area criterion.

5.

Write the swing equation used for stability analysis of power system.

6.

Write any two assumptions made to simplify the transient Stability problems.

7.

Write the swing-equation for a single synchronous machine connected to an infinite bus

8.

Write the concept of critical clearing angle.

9.

Define steady state stability limit.

10.

State equal area criterion.

11.

In a 3-machine system having ratings S1 S2 and S3 and inertia constants M1 M2 and M3, what

is inertia constant M and H of the equivalent system?

12.

List any two methods of improving the transient stability limit of power system.

13.

Define swing curve. What is the use of swing curve?

14.

Write the power-angle equation of a synchronous machine connected to an Infinite bys and also

the expression for maximum power transferable to the bus.

15.

Define critical clearing time.

PART- B


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1.

Derive swing equation used for stability studies in power system. (16)

2.

Explain the modified Euler method of analyzing multi machine power system for stability with a

neat flow chart. (16)

3.(i) Derive swing equation for a synchronous machine. (8)

(ii) A 50 Hz generator is delivering 50% of the power that it is capable of delivering through a

transmission line to an infinite bus. A fault occurs that increases the reactance between the

generator and the infinite bus to 500% of the value before the fault. When the fault is isolated,

the maximum power that can be delivered is 75% of the original maximum value. Determine the

critical clearing angle for the condition described. (8)

4. Find the critical clearing angle for clearing the fault with simultaneous opening of the

breakers 1 and 2. The reactance values of various components are indicated on the

diagram. The generator is delivering 1.0 p.u. power at the instant preceding the fault. The

fault occurs at point p as shown in the figure.

(16)

5 In the system shown in Fig. 5 a three phase static capacitive reactor of reactance 1 p.u. per

phase in connected through a switch at motor bus bar. Calculate the limit of steady




state power with and without reactor switch closed. Recalculate the power limit with capacitance

reactor replaced by an inductive reactor of the same value. (16)

Fig.5

Assume the internal voltage of the generator to be 1.2 pu. and motor to be1.0 p.u.

6. Describe the Runge-Kutta method of solution of swing equation for multi-machine

systems. (16)

7. (i) Derive the swing equation of a synchronous machine swinging against an infinite bus.

Clearly state the assumption in deducing the swing equation. (10)

(ii) The generator shown in Fig. 7 is delivering power to infinite bus. Take Vt = 1.1 p.u. Find the

maximum power that can be transferred when the system is healthy. (6)

Fig. 7

9.

(i) A 2-pole 50 Hz, 11kV turbo alternator has a ratio of 100 MW, power factor 0.85

lagging. The rotor has a moment of inertia of 10,000 kgm2. Calculate H and M. (6)


25/42

(ii)A three phase fault is applied at the point P as shown below. Find the critical clearing angle

for clearing the fault with simultaneous opening of the breakers 1 and 2. The reactance values

of various components are indicated in the diagram. The generator is delivering 1.0 p.u. power

at the instant preceding the fault. (10)

10. Describe the equal area criterion for transient stability analysis of a system. (16)

CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 1

KINGSCOLLEGE OF ENGINEERING

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERINGQUESTION BANKSUBJECT CODE: CS1358 YEAR : IIISUBJECT NAME: COMPUTER ARCHITECTURE SEM : VI

UNIT-1BASIC STRUCTURE OF COMPUTERSPART- A (2 marks)1. Define interrupt and ISR.2. Define Bus. What are the different buses in a CPU?3. Compare single bus structure and multiple bus structure?4. What is System Software? Give an example?5. What is Application Software?

6. What is multiprogramming or multitasking?7. Define clock rate.8. Write down the basic performance equation?9. What is big endian and little endian format?10. What are condition code flags?11. What are the commonly used condition code flags?12. Define addressing mode.13. What the various addressing modes?14. Define device interface.15. What are the various units in the computer?16. What is an I/O channel?17. What is a bus?18. Define word length.CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 219. Explain the following the address instruction?20. What is the straight-line sequencing?21. What is stack?22. What is a Queue?PART-B(16 Marks)


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1. Explain the various generations of Computer (16)2. Explain the basic functional units of a simple computer. (16)3. Describe the different classes of instructions format with example. (16)4. Explain various addressing modes found in modern processors (16)5. What are stack and queues? Explain its use and give its differences (16)6. Write short notes on software performance and Memory locations and address .(16)UNIT-2ARITHMETICPART- A (2 marks)1. Give an example each of zero- address, one-address, two-address and three-addressinstructions.2. What is booth algorithm?3. Write down the steps for restoring division and non-restoring division.

4. What is the advantage of non restoring over restoring division?5. Briefly explain the floating point representation with an example?6. What are guard bits?7. What are the ways to truncate guard bits?

8. What are the two attractive features of Booth algorithm?9. What are the two techniques for speeding up the multiplication operation?10. How bit pair recoding of multiplier speeds up the multiplication process?CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 3PART-B(16 Marks)1. (a) Discuss the principle of operation of carry-look ahead adders. (08)(b) Discuss the non-restoring division algorithm. Simulate the same for 23/5. (08)2. (a) Multiply the following pair of signed 2s complements numbers using bit pairrecoded multiplier: Multiplicand = 110011 Multiplier = 101100. (08)(b) Describe the algorithm for integer division with suitable example. (08)3. Describe how the floating-point numbers are represented and used in digital arithmetic

operations. Give an example. (16)4. (a) Explain the representations of floating point numbers in detail. (06)(b) Give the block diagram of the hardware implementation of addition and subtraction ofsigned number and explain its operations. (10)5. (a) Design a multiplier that multiplies two 4-bit numbers. (06)(b) Explain the working of floating point adder and subtractor. (10)UNIT-3BASIC PROCESSING UNITPART- A (2 marks)1. Name two special purpose registers.2. Define datapath.

3. Define processor clock.4. Define register file.5. What are the two approaches used for generating the control signals in propersequence?6. What are the factors determine the control signals?7. What are the features of the hardwired control.8. What is micro programmed control?9. What is control word?10. Define micro routine and microinstruction.


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11. Name some register output control signals.12. What is vertical organization and horizontal organization?13. Compare vertical organization and horizontal organization.CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 414. What is the drawback of micro programmed control?15. Name the four steps in pipelining.16. What is data hazard?17. What are instruction hazards?18. What are called stalls?19. What is structural hazard?20. What is said to be side effect?21. What is branch folding?22. Define speculative execution.23. What is called static and dynamic branch prediction?PART-B(16 Marks)1. Give the organization of typical hardwired control unit and explain the functions

performed by the various blocks. (16)2. Discuss the various hazards that might arise in a pipeline. What are the remediescommonlyadopted to overcome/minimize these hazards. (16)3. Explain in detail about instruction execution characteristics. (16)4. With a neat block diagram, explain in detail about micro programmed control unit andexplainits operations. (16)5. (a) Explain the execution of an instruction with diagram. (08)(b) Explain the multiple bus organization in detail. (08)6. (a) Explain the function of a six segment pipeline showing the time it takes to processeight

tasks. (10)(b) Highlight the solutions of instruction hazards. (06)UNIT-4MEMORY SYSTEMPART- A (2 marks)1. Define memory access time.2. Define memory cycle time.3. What is MMU?CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 54. Define static memories.

5. What are the Characteristics of semiconductor RAM memories?6. What are the Characteristics of SRAMs?7. What are the Characteristics of DRAMs?8. Define Memory Latency.9. What are asynchronous DRAMs?10. What are synchronous DRAMs?11. What is double data rate SDRAMs?12. What are SIMMs and DIMMs?


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13. What is memory Controller?14. Differentiate static RAM and dynamic RAM.15. What are RDRAMs?16. What are the special features of Direct RDRAMs?17. What are RIMMs?18. Define ROM.PART-B(16 Marks)1. (a) Discuss the various mapping techniques used in cache memories. (08)(b) A computer system has a main memory consisting of 16 M words. It also has a 32Kwordcache organized in the block-set-associative manner, with 4 blocks per set and 128 wordsper block.Calculate the number of bits in each of the TAG, SET and WORD fields of the main memoryaddress format. How will the main memory address look like for a fully associative mappedcache?(08)2. (a) Explain the concept of virtual memory with any one virtual memory management

technique.(08)(b) Give the basic cell of an associative memory and explain its operation. Show howassociative memories can be constructed using this basic cell. (08)3. Give the structure of semiconductor RAM memories. Explain the read and writeoperations indetail. (16)4. Explain the organization of magnetic disks in detail. (16)CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 65. (a) A digital computer has a memory unit of 64K*16 and a cache memory of 1K words.The

cache uses direct mapping with a block size of four words. How many bits are there in thetag,index, block and word fields of the address format? How many blocks can the cachesaccommodate? (16)UNIT-5I/O ORGANIZATIONPART- A (2 marks)1. What is program controlled I/O?2. What are the various mechanisms for implementing I/O operations?3. What are vectored interrupts?4. When the privilege exception arises?

5. What is time slicing?6. What is memory mapped I/O?7. What is DMA?8. What is DMA controller?9. What is cycle stealing?10. What is bus arbitration?11. What are the three types of buses?12. What are the objectives of USB?


29/42

13. What is synchronous bus?14. What is asynchronous bus?15. What are the functions of typical I/O interface?PART-B(16 Marks)1. Explain the functions to be performed by a typical I/O interface with a typical input outputinterface. (16)2. (a) Discuss the DMA driven data transfer technique. (08)(b) Discuss the operation of any two input devices (08)3. Explain in detail about interrupt handling. (16)4. Explain in detail about standard I/O interface. (16)CS1358 COMPUTER ARCHITECTUREKINGS COLLEGE OF ENGINEERING/CS1358/COMPUTER ARCHITECTURE 75. Describe the functions of SCSI with a neat diagram. (16)6. (a) What is the importance of I/O interface? Compare the features of SCSI and PCIinterfaces.(08)(b) Explain the use of vectored interrupts in processes. Why is priority handling desired in

Interrupt controllers? How does the different priority scheme work? (08)7. Write notes on the following. (16)

DIGITAL SIGNAL PROCESSINGYEAR / SEM: III / V

UNIT ISIGNALS

PART A (2 MARKS)

1. Define even and odd signals.

2. State the disadvantages of digital signal processing over analog process.

3. Check whether the following system is time-variant y(n)=nx2(n).

4. What are the different types of signal representation?

5. Define DFT pair.

6. Define the following (a) System (b) Discrete-time system

7. List the merits and demerits of DSP:

8. When discrete time signals called as periodic signals?

9. Write properties of convolution.

10. What is static and dynamic system?

11. What are the classification of discrete-time systems?

12. What is linear and non-linear system?


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13. State sampling theorem.

14. What is an anti-aliasing filter?

15. What is aliasing effect?

16. What is a Causal system?

17. What is SISO system and MIMO system?

18. Define a Stable System.

19. What is an LTI system?

20. What is a Shift invariant (or) Time-invariant system?

21. Define Quantization.

PART B

1. Explain in detail about the classification of discrete time systems. (16)

2. (a) Describe the different types of discrete time signal representation. (6)

(b) Define energy and power signals. Determine whether a discrete time unit step

signal x(n) = u(n) is an energy signal or a power signal. (10)

3. (a) Give the various representation of the given discrete time signal

x(n) = {-1,2,1,-2,3} in Graphical, Tabular, Sequence, Functional and Shifted

functional. (10)

(b) Give the classification of signals and explain it. (6)

4. (a) Draw and explain the following sequences:i) Unit sample sequence

ii) Unit step sequence

iii) Unit ramp sequence

iv) Sinusoidal sequence and

v) Real exponential sequence (10)

(b) Determine if the system described by the following equations are causal or

noncausal

i) y(n) = x(n) + (1 / (x(n-1)) ii) y(n) = x(n2) (6)

5. Determine the values of power and energy of the following signals. Find whether the

signals are power, energy or neither energy nor power signals.

i) x(n) = (1/3)n u(n) ii) x(n) = ej((/2)n + (/4)

iii) x(n) = sin (/4)n iv) x(n) = e2n u(n) (16)


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6. (a) Determine if the following systems are time-invariant or time-variant

i) y(n) = x(n) + x(n-1) ii) y(n) = x(-n) (4)

(b) Determine if the system described by the following input-output equations are

linear or non-linear.

i) y(n) = x(n) + (1 / (x(n-1)) ii) y(n) = x2(n) iii) y(n) = nx(n) (12)

7. Test if the following systems are stable or not.

i) y(n) = cos x(n) ii) y(n) = ax(n)

iii) y(n) = x(n) en iv) y(n) = ax(n) (16)

8. (a) Determine the stability of the system y(n)(5/2)y(n-1) + y(n-2) = x(n)x(n-1) (8)

(b) Briefly explain about quantization. (8)

9. (a) Explain the principle of operation of analog to digital conversion with a neat

diagram. (8)

(b) Explain the significance of Nyquist rate and aliasing during the sampling of

continuous time signals. (8)

10. (a) List the merits and demerits of Digital signal processing. (8)

(b) Write short notes about the applications of DSP. (8)

UNIT IIDISCRETE TIME SYSTEM ANALYSIS

PART A (2 MARKS)

1. Define Z-transform.

2. What is meant by Region of convergence?

3. What are the properties of ROC?

4. List the properties of z-transform.

5. Explain the linear property of z-transform.

6. Explain the time-shifting property of z-transform.

7. What are the different methods of evaluating inverse z-transform?

8. What are the properties of frequency response H(ei) of an LTI system?

9. What is the necessary and sufficient condition on the impulse response of stability?

10. Distinguish between Linear convolution and circular convolution.

11. How will you obtain linear convolution from circular convolution?

12. What is meant by sectioned convolution?


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13. What are the two methods used for te sectional convolution?

14. Distinguish between Overlap add and Overlap save method.

15. Distinguish between DFT and DTFT.

16. Distinguish between Fourier series and Fourier transform.

PART B

1. (a) Obtain the transfer function and impulse response of the LTI system defined by

y(n-2)+5y(n-1)+6y(n)+x(n) (8)

(b) State and prove convolution property of discrete time fourier transform. (8)

2. (a) State and prove any tow properties of z-transform. (8)

(b) Find the z-transform and ROC of the causal sequence. (4)

X(n) = {1,0,3,-1,2}

(c) Find the z-transform and ROC of the anticausal sequence (4)

X(n) = {-3,-2,-1,0,1}

3. (a) Determine the z-transform and ROC of the signal i) x(n) = a nu(n) and

ii) x(n) = -bnu(-n-1) (12)

(b) Find the stability of the system whose impulse response h(n) = (2) nu(n) (4)

4. (a) Determine the z-transform of x(n) = cos n u(n) (6)

(b) State and prove the following properties of z-transform. (10)

i) Time shiftingii) Time reversal

iii) Differentiation

iv) Scaling in z-domain

5. (a) Determine the inverse z-transform of x(z) = (1+3z-1) / (1+3z-1+2z-2) for z >2 (8)

(b) Compute the response of the system y(n) = 0.7y(n-1)-0.12y(n-2)+x(n-1)+x(n-2) to

input x(n) = nu(n).Is the system is stable (8)

6. Find the inverse z-transform of x(z) = (z2+z) / (z-1)(z-3), ROC: z > 3. Using (i) Partial

fraction method, (ii) Residue method and (iii) Convolution method. (16)

7. (a) Determine the unit step response of the system whose difference equation is

y(n)-0.7y(n-1)+0.12y(n-2) = x(n-1)+x(n-2) if y(-1) = y(-2) = 1. (8)

(b) Find the input x(n) of the system, if the impulse response h(n) and the output y(n)

as shown below. (8)


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h(n) = {1,2,3,2} y(n) = {1,3,7,10,10,7,2}

8. (a) Determine the convolution sum of two sequences x(n) = {3,2,1,2}, h(n) = {1,2,1,2}

(8)

(b) Find the convolution of the signals

x(n) = 1 n = -2,0,1

= 2 n = -1

= 0 elsewhere

h(n) = (n)-(n-1)+ (n-2)- (n-3) (8)

9. (a) Determine the output response y(n) if h(n) = {1,1,1,1}; x(n) = {1,2,3,1} by using

i) Linear convolution ii) Circular convolution and iii) Circular convolution with zero

padding. (12)

(b) Explain any twp properties of Discrete Fourier Transform. (4)

10. Using linear convolution find y(n) = x(n)*h(n) for the sequences x(n) = (1,2,-1,2,3,-2,

-3,-1,1,1,2,-1) and h(n) = (1,2).Compare the result by solving the problem using

i) Over-lap save method and ii) Overlapadd method. (16)

11. For the sequences given below, find the frequency response, plot magnitude

response, phase response and comment. (16)

i) x(n) = 1 for n = -2,-1,0,1,2

= 0 otherwise

ii) x(n) = 1 for n = 0,1,2,3,4

= 0 otherwise

12. (a) Calculate the frequency response for the LTI systems representation

i) h(n) = [1/n]n u(n) ii) h(n) = (n)(n-1) (8)

(b) Find the frequency response of the system having impulse response

h(n) = [1/2] { (1/2)n + (-1/4)n } u(n) (8)

13. Determine the frequency response (H(ej)) for the system and plot magnituderesponse and phase response. y(n)+[1/4]y(n-1) = x(n)-x(n-1) (16)

14. (a) A discretetime system has a unit sample response h(n) given by

h(n) = [1/2] (n) + (n-1) + [1/2] (n-2). Find the system frequency response H(ej);

Plot magnitude and Phase response. (12)


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(b) Explain any two properties of Discrete Fourier Series. (4)

UNIT IIIDISCRETE FOURIER TRANSFORM AND COMPUTATION

PART

A (2 MARKS)

1. Why FFT is needed?

2. What is the main advantage of FFT?

3. What is FFT?

4, What is meant by Radix-2 FFT?

5. What is decimation-in-time algorithm?

6. What is decimation in frequency algorithm?

7. What are the differences and similarities between DIF and DIT algorithm?8. What is the basic operation of DIT algorithm?

9. What is the basic operation of DIF algorithm?

10. What are the applications of FFT algorithms?

11. Draw the flow graph of a two point DFT for a decimation-in-time decomposition.

12. Draw the flow graph of a two point radix-2 DIF FFT.

13. Draw the basic butterfly diagram for DIT algorithm.

14. Draw the basic butterfly diagram for DIF algorithm.

PART

B

1. Describe the decimation in time [DIT] radix-2 FFT algorithm to determine N-point

DFT. (16)

2. An 8-point discrete time sequence is given by x(n) = {2,2,2,2,1,1,1,1}. Compute the

8-point DFT of x(n) using radix-2 FFT algorithm. (16)

3. (a) Compute the 4-point DFT and FFT-DIT for the sequence x(n) = {1,1,1,3} and

What are the basic steps for 8-point FFT-DIT algorithm computation? (12)

(b) What is the advantage of radix-2 FFT algorithm in comparison with the classicalDFT method? (4)

4. (a) Perform circular convolution of the two sequences graphically x 1(n) = {2,1,2,1}

and x2(n) = {1,2,3,4} (6)

(b) Find the DFT of a sequence by x(n) = {1,2,3,4,4,3,21} using DIT algorithm. (10)


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5. (a) Explain the decimation in frequency radix-2 FFT algorithm for evaluating N-point

DFT of the given sequence. Draw the signal flow graph for N=8. (12)

(b) Find the IDFT of y(k = {1,0,1,0} (4)

6. (a) Find the circular convolution of the sequences x1(n)= {1,2,3} and x2(n) = {4,3,6,1}

(8)

(b) Write the properties of DFT and explain. (8)

7. (a) Draw the 8-point flow diagram of radix-2 DIF-FFT algorithm. (8)

(b) Find the DFT of the sequence x(n) = {2,3,4,5} using the above algorithm. (8)

8. (a) What are the differences and similarities between DIT and DIF FFT algorithms?

(6)

(b) Compute the 8-point IDFT of the sequence x(k) = {7, -0.707-j0.707, -j,

0.707-j0.707, 1, 0.707+j0.707, j, -0.707+j0.707} using DIT algorithm. (10)

9. (a) Compute the 8-point DFT of the sequence x(n) = {0.5,0.5,0.5,0.5,0,0,0,0} using

radix-2 DIT algorithm. (8)

(b) Find the IDFT of the sequence x(k) = {4,1-j2.414,0,1-j0.414,0,1+j.414,0,1+j2.414}

using DIF algorithm. (8)

10. Compute the 8-point DFT of the sequence

x(n) = 1, 0 n 7

0, otherwise by using DIT,DIF algorithms. (16)UNITIV

DESIGN OF DIGITAL FILTERSPART A (2 MARKS)

1. What is FIR Filter?

2. Write the procedure for designing FIR filters

3. Write the characteristics of FIR filter.

4. What are the design techniques available for the designing FIR filter?

5. What are the demerits of FIR filter?

6. What are the possible types of impulse response for linear phase FIR filters?

7. What is GIBBS phenomenon?

8. Write the desirable characteristics of frequency response of window functions.

9. Write the characteristics features of rectangular window.

10. List merits and demerits of rectangular window.


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11. List the features of Kaiser Window.

12. What do you understand by linear phase response?

13. What are the two types of filter based on the impulse response?

14. What are the advantages of Kaiser Window?

15. What is the principle of designing FIR filter using frequency sampling method?

16. What are the properties of FIR filter?

17. What is the need for employing window technique for FIR filter design? (Or)

What is window and why it is necessary?

18. What is the necessary and sufficient condition for linear phase characteristic in FIR

filter?

19. Define IIR filter.

20. What are the methods available for designing analog IIR filter?

21. What are the methods available for designing analog IIR filter?

22. Mention the importance of IIR filter:

23. Mention the two properties of Butterworth low pass filter.

24. Write the properties of chebyshev type-I filter:

25. What is aliasing? Why it is absent in bilinear transformation ?

26. How one can design digital filter from analog filter ?

27. What is bilinear transformation?

28. What is warping effect?

29. Write merits and demerits of bilinear transformation.

30. What is the main advantage of direct-form II realization when compared to

directform

I realization?

31. What is the main disadvantage of direct-form realization?

32. What is the advantage of cascade realization?33. Distinguish IIR and FIR.

34. Compare analog and digital filter.

35. Compare Butterworth and Chebyshev Filter:

36. Compare impulse invariant and bilinear technique


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37. What are the different types of structures for realization of IIR systems?

38. Write a short note on prewarping.

PART B

1. Describe the impulse invariance and bilinear transformation methods used for

designing digital IIR filters. (16)

2. (a) Obtain the cascade and parallel realization of the system described by

y(n) = -0.1y(n-1)+0.2y(n-2)+3x(n)+3.6x(n-1)+0.6x(n-2) (10)

(b) Discuss about any three window functions used in the design of FIR filters. (6)

3. Determine the direct form II and parallel form realization for the following system.

y(n) = -0.1y(n-1)+0.72y(n-2)+0.7x(n)-0.252x(n-2) (16)

4. An analog filter has a transfer function H(s) = (10 / s2+7s+10). Design a digital filter

equivalent to this impulse invariant method. (16)

5. For the given specifications design an analog Butterworth filter,

0.9 H(j) 1 for 0 0.2

H(j) 0.2 for 0.4 (16)

6. Design a digital Butterworth filter satisfying the constraints

0.707 H(ej) 1 for 0 /2

H(ej) 0.2 for 3

With T = 1 sec using Bilinear transformation. (16)

7. Design a chebyshev filter for the following specification using impulse invariance

method. 0.8 H(ej) 1 for 0 0.2

H(ej) 0.2 for 0.6 (16)

8. (a) Write the expressions for the Hamming, Hanning, Bartlett and Kaiser windows.(6)

(b) Explain the design of FIR filters using windows. (10)

9. Design an ideal high pass filter with

Hd(ej) = 1 for /4

= 0 for /4

Using Hanning window for N=11. (16)

10. Design an ideal high pass filter with

Hd(ej) = 1 for /4

= 0 for /4


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Using Hamming window for N=11. (16)

11. Using a rectangular window technique design a lowpass filter with pass band gain of

unity, cutoff frequency of 1000 Hz and working at a sampling frequency of 5kHZ. The

length of the impulse response should be 7. (16)

12. Design an ideal Hilbert transformer having frequency response

H(ej) = j for - 0

= -j for 0

Using blackman window for N=11.Plot the frequency response. (16)

UNIT VPROGRAMMABLE DSP CHIPS

PART A (2 MARKS)

1. What are the classifications of digital signal processors?

2. What are the factors that influence the selection of DSPs?

3. What are the applications of PDSPs?

4. Mention the different addressing modes in TMS320C54x processor.

5. What is meant by pipelining?

6. Give the digital signal processing application with the TMS 320 family.

7. What are the desirable features of DSP Processors?

8. What are the different types of DSP Architecture?

9. State the features of TMS3205C5x series of DSP processors.10. Define Parallel logic unit?

11. Define scaling shifter?

12. Define ARAU in TMS320C5X processor?

13. What are the Interrupts available in TMS320C5X processors?

14. What are the three quantization errors due to finite word length registers in digital

filters?

15. What do you understand by input quantization error?

16. What is co-efficient quantization error?

17. What is product quantization error? (or) What is product round-off error in DSP?

18. What are the different methods of quantization?

19. Define Truncation and Rounding.

20. What is the effect of quantization on pole locations?


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21. Which realization is less sensitive to the process of quantization?

22. What is meant by quantization step size?

23. What are the two kinds of limit cycle behavior in DSP?

24. Define Dead band of the filter.

25. Explain briefly the need for scaling in the digital filter implementation.

26. Why rounding is preferred to truncation in realizing digital filter?

PART B

1. Describe in detail the architectural aspects of TMS320C54 digital signal processor

using an illustrative block diagram. (16)

2. Explain the various addressing modes and salient features of TMS320C54X. (16)

3. (a) Describe the function of on-chip peripherals of TMS320C54 processor. (12)

(b) What are the different buses of TMS320C54 and their functions? (4)

4. Describe the errors introduced by quantization. Explain the impact of quantization

of filter coefficients on the location of poles. (16)

5. Write a brief note on:

i) Input quantization (8)

ii) Limit cycles (8)

6. Discuss in detail the various quantization effects in the design of digital filters. (16)

7. Find the effect of co-efficient quantization on pole locations of the given second

order IIR system, when it is realized in direct form I and in cascade form. Assume a

word length of 4 bits through truncation. (16)

H(z) = 1 / (10.9 z-1 + 0.2 z-1)

***************************

PRINCIPLES OF MANAGEMENT SEMESTER : VIQUESTION BANK

UNIT 12 Marks

1. Define Management.2. Define Productivity.3. What are the functions of Managers?4. Write the different levels of Management.


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5. What is meant by social audit?6. What are the effective characteristics of Managers?7. Define Organization.8. Define effectiveness.9. Define efficiency.10. Give the main importance of management.

16 Marks1. Explain briefly about the various functions of Management.2. What are the Henry Fayols 14 principles of management? Explain.3. Explain briefly about the different factors affecting the organizationalenvironment.4. Explain the overall development of management thought.5. Management : Science or ArtDiscuss.6. Compare Management and administration.7. Explain in detail about the different types of business organization.8. Write the characteristics and limitations of classical approach.9. What are the different responsibilities of managers in effective

management? Explain.10. Discuss in detail about the recent trends in management concepts.

UNIT 22 Marks

1. Define planning2. Define strategies.3. Define objectives and goals.4. What are the different types of plans?5. What is meant by policies?6. State the various steps in planning.7. Define MBO.8. Define Programs.

9. Define TOWS matrix.10. What do you understand by decision making?

16 marks1. Explain the overall decision making process.2. Explain in detail about the various forecasting methods.3. Explain the process of MBO.4. Explain in detail about the TOWS matrix and SWOT analysis.5. Define policies with its types. Explain the planning premises with types.6. Explain the relationship of planning and controlling.7. Discuss in detail about the performance appraisal.8. Name the classifications of planning practices.

9. Discuss the various factors affecting the decision making process.10. Explain briefly about the major kinds of strategies.UNIT 3

2 Marks1. Define span of management.2. Give the main difference between the formal and informalorganization.3. List out the steps involved in organizing.


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4. Discuss Departmentation.5. What are the different bases of departmentation?6. Define decentralization.7. What is organization chart?8. Define staffing.9. What is meant by performance appraisal?10. What is human resource planning?

16 Marks1. Explain briefly about the various types of Departmentation.2. Explain briefly about the various types of Organizational structures.3. Discuss the span of management/managerial effectiveness.4. Explain briefly about the overall selection process.5. Discuss briefly the various steps involved in organizing.6. List out the difference between Formal and Informal organization.7. List out the basic activities of human resource development.8. Name the types of centralization.9. Explain about the organizational culture.

10. Explain about the human resource planning.UNIT 4

2 Marks1. Define Leading.2. What are the difference between creativity and innovation?3. Define Motivation.4. What are the elements in the Maslow hierarchy of needs?5. Define Leadership.6. List out the various styles of leadership with examples.7. Define Communication.8. What is meant by downward communication?9. Define Operations Research.

10. What do you understand by JIT?16 Marks

1. Explain briefly about three theories of Motivation.2. Explain in detail about the various functions of Leader.3. Discuss in detail about the Creativity and Innovation.4. Explain the various types of Leadership with its different styles.5. Discuss in detail about the process and types of Motivation.6. Explain the different characteristics of a Leader.7. List the tools and techniques used in operating managementsystem.8. Explain briefly about MIS.

9. Explain the different barriers and breakdowns of communicationprocess.10. Explain in detail about the different types of Budgets.11. Difference between Motivation and Satisfaction.

Unit 5 (2 Marks)1. Define Controlling.2. What are the steps involved in the control process?3. Define budgeting.


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4. What is meant by MIS?5. What is international business?6. Define Globalisation.7. What is MNC? Give an example.8. Define Reporting.9. What are the benefits of IT in controlling?10. What do you mean by PERT?

16 Marks1. Explain the difference between Japanese and US Management.2. Explain in detail about MNCs.3. Discuss in detail about the techniques used for improvingProductivity.4. Explain the term Reporting.5. Explain in detail the preventive control mechanism towardsachieving a unified global management theory.6. Impact of IT in Management conceptDiscuss.7. Discuss in briefly about the various functions of MNC.

8. Explain in detail about the Globalization and Liberalization.9. Explain in detail reporting and ROI.10. Write down the management concept in Germany.11. Explain in detail the various forms of International business

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