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    PRODUCTION AND INVENTORY

    MANAGEMENT JOURNAL

    VOLUME 49, NO. 1 2014

    A Concepual Framework for Invenory Managemen:

    Focusing on Low-Consumpion Iems

    Peter Wanke

    Inegraing FMEA wih he Supply Chain Risk Managemen

    Processes o Faciliae Supply Chain Design Decisions

    V.M. Rao Tummala, Tobias Schoenherr, CSCP, Thomas Harrison

    Operaions Managemen Salary Repor

    L. Drew Rosen, Thomas Janicki, Judith Gebauer

    A Tuorial on Managerial Cos Accouning: Year-End Reporing

    Timothy D. Fry, Kirk D. Fiedler

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL2

    ABOUT THE PRODUCTION AND INVENTORY

    MANAGEMENT JOURNAL

    Through he suppor of APICS Foundaion, he P&IM Journal is commited

    o being he premier oule for managerial-focused research in operaionsand supply chain managemen. The APICS Foundaion 2014 board officersand members are:

    President:Karl Klaesius, CPIM, KS&E Enerprises

    Vice President: Shari Ruelas, CPIM, CSCP, Chevron Producs

    Treasurer: Rober Vokurka, PhD, CPIM, CIRM, CSCP

    Barbara Flynn, PhD, Richard M. and Myra Louise Buskirk Professor ofManufacuring Managemen, Kelley School of Business, Indiana Universiy

    Alan Dunn, CPIM, GDI Consuling and Training Company

    Kaie Fowler, Schlumberger

    Anonio Galvao, CSCP, Sealed Air Inc.

    Michael Wasson, CSCP, Coca-Cola Norh America

    Paul Pitman, PhD, Indiana Universiy Souheas

    Marco Ugare, PhD, CPIM, CSCP, MillerCoors

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    TABLE OF CONTENTS

    PRODUCTION AND INVENTORY

    MANAGEMENT JOURNAL

    Articles

    A Conceptual Framework for Inventory Management: Focusing on

    Low-Consumption Items

    by Peer Wanke

    Integrating FMEA with the Supply Chain Risk Management Processes

    to Facilitate Supply Chain Design Decisionsby V.M. Rao Tummala, Tobias Schoenherr, CSCP and Thomas Harrison

    Operations Management Salary Report

    by L. Drew Rosen, Thomas Janicki, Judih Gebauer

    A Tutorial on Managerial Cost Accounting: Year-End Reporting

    by Timohy D. Fry, Kirk D. Fiedler

    Editorial Staff Information

    Robert L. BregmanEdior in Chief

    Associae Professor

    Decision and Informaion Sciences Deparmen

    Universiy of Houson

    [email protected]

    6

    24

    71

    83

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL4

    ARTICLE SUMMARIES

    A CONCEPTUAL FRAMEWORK FOR INVENTORY MANAGEMENT:

    FOCUSING ON LOW CONSUMPTION

    This aricle evaluaes he premise o demand adherence o normal disribuion

    in invenory managemen models, showing ha his can lead o significan

    disorions, mainly o sock conrol o very low and low consumpion iems.

    The aricle hus proposes a ramework o help managers deermine he bes

    sock policy o be adoped given produc demand characerisics. The aricle

    also presens he use o such a ramework in a case sudy, in an atemp o

    illusrae he benefis o adoping probabiliy densiy uncions ha are more

    adequae o produc demand characerisics, in erms o oal coss o socks.

    INTEGRATING FMEA WITH THE SUPPLY CHAIN RISK

    MANAGEMENT PROCESS TO FACILITATE SUPPLY CHAIN

    DESIGN DECISIONS

    We presen a novel approach o inegraing ailure mode and effec analysis

    (FMEA) wih a supply chain risk managemen process (SCRMP). Focusing on

    he challenging ask o assess and manage supply-side risks in global supply

    chains, he approach developed offers an effecive and affordable way or

    firms o provide decision suppor or he selecion o heir mos appropriae

    supply chain design. The aim o he inegraed approach combining he

    srenghs o FMEA and SCRMP is o gaher as much perinen inormaion

    as possible, o srucure i, and o comprehensively delineae all poenialsupply chain risk acors, offering valuable decision suppor. We illusrae

    he applicaion o he approach a Michigan Ladder Company, where i was

    applied o wo specific supply chains or he procuremen o fiberglass ladders.

    Specifically, one supply chain spanned rom China o he U.S. via Mexico

    (aking advanage o a Mexican maquiladora), and one spanned rom China

    direcly o he U.S. The combinaion o FMEA and he SCRMP enhanced he

    manuacurers confidence in is supply chain design decision, and enabled he

    firm o proacively manage is supply-side risks. Overall, he aricle is mean o

    moivae praciioners o embark on he journey o acive risk managemen.

    While some may perceive risk managemen as a dauning ask or being

    primarily employed by larger firms, we provide guidance or firms o any sizeo apply he approach i can be done, and does no have o consume an

    inordinae amoun o resources.

    OPERATIONS MANAGEMENT SALARY REPORT

    APICS, in conjuncion wih he Cameron School o Business a he Universiy

    o Norh Carolina Wilmingon, is pleased o provide he resuls o he 2013

    Operaions Managemen Salary Repor. The daa are colleced rom a random

    sample o more han 30,000 operaions managemen proessionals worldwide.

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    VOLUME 49, NO. 1 5

    Twice annually, approximaely fify percen o he APICS membership and

    cusomer base receives a reques o complee an online survey collecing daa

    concerning curren salary and compensaion by job uncion and ile. The

    survey can be accessed a: htp://csbapp.uncw.edu/apics/.

    A TUTORIAL ON MANAGERIAL COST ACCOUNTING: YEAREND

    REPORTING

    Building on he companion aricle A Tuorial on Managerial Cos Accouning:

    Living wih Variances by Fry and Fiedler (2011), his curren paper picks

    up where he previous paper lef off and illusraes how he managemen

    accouning sysem (MCA) is linked o financial accouning (FA) o generae

    he year-end financial repors required by shareholders, banks, and he IRS.

    The prior paper ocused on he deailed use o inormaion provided by he

    MCA hroughou he year and walked hrough he developmen o he yearly

    budge, calculaion o produc coss, deerminaion o budge variances,

    derivaion o he periodic income and saemen o cash flows repors, and

    provides possible examples o dysuncional behavior a a ficiious company

    called Mandrake Manuacuring. This uorial concenraes on he ineracion

    o he MCA and FA sysems and he producion o year end FA saemens. In

    addiion o providing inormaion such as cos o goods sold, invenory values,

    and operaing sandards o he FA, he year-end inormaion provided by he

    MCA is also used o develop nex years budges. In his presen paper, he

    conversion o he MCA repors ino he FA repors will be presened. Also, he

    impac o he MCA repors on uure budges will be discussed. As poinedou in F&F, i is vial ha operaions managers undersand how he accouning

    sysems used by heir company uncion. Wihou such undersanding, many

    o he problems associaed wih he improper use o he accouning sysems

    will never be correced.

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL6

    A CONCEPTUAL FRAMEWORK FOR

    INVENTORY MANAGEMENT: FOCUSING ON

    LOW CONSUMPTION ITEMS

    Peer Wanke (Corresponding Auhor)

    Center for Logistics Studies, Infrastructure, and Management, The COPPEAD

    Graduate School of Business, Federal University of Rio de Janeiro, Rio de

    Janeiro Brazil 21949-900

    ABSTRACT

    This aricle evaluaes he premise o demand adherence o normal disribuion

    in invenory managemen models, showing ha his can lead o significandisorions, mainly o sock conrol o very low and low consumpion iems.

    The aricle hus proposes a ramework o help managers deermine he bes

    sock policy o be adoped given produc demand characerisics. The aricle

    also presens he use o such a ramework in a case sudy, in an atemp o

    illusrae he benefis o adoping probabiliy densiy uncions ha are more

    adequae o produc demand characerisics, in erms o oal coss o socks.

    Keywords: sock, lead-ime demand, coefficien o variaion, ramework, coss

    . Introduction

    Invenory managemen permeaes decision-making in counless firmsand has been exensively sudied in he academic and corporae spheres

    (Rosa e al. 2010). The key quesions usually influenced by a variey o

    circumsances which invenory managemen seeks o answer are: when

    o order, how much o order and how much sock o keep as saey sock

    (Nami and Chen 1999; Silva 2009). According o Wanke (2011a), invenory

    managemen involves a se o decisions ha aim a maching exising

    demand wih he supply o producs and maerials over space and ime

    in order o achieve specified cos and service level objecives, observing

    produc, operaion, and demand characerisics.

    These diverse circumsances ha should be aken ino accoun or anappropriae selecion o invenory managemen models have conribued

    o he developmen o research and producion o aricles on possible

    qualiaive concepual schemes also known as classificaion approaches

    aimed a supporing decision-making (Huiskonen 2001). There are several

    examples o his kind hroughou he years.

    Williams (1984), or example, developed an analyical mehod o classiy

    demand as regular (high consumpion), low consumpion, or inermiten, by

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    VOLUME 49, NO. 1 7

    decomposing he variabiliy o lead-ime demand ino hree pars: variabiliy

    o he number o occurrences per uni o ime, variabiliy o demand size,

    and lead-ime variabiliy. Boter and Foruin (2000) based heir classificaion

    o iems on hree crieria: lead ime, price, and consumpion level, which

    underpin he developmen o eigh differen invenory managemen models.

    Eaves and Kingsman (2004) revisied Williams (1984) model, reclassiying

    spare pars ino five caegories: smooh, erraic, low urnover, slighly

    sporadic, and srongly sporadic. Syneos, Boylan and Croson (2005) classiy

    iems ino our quadrans, divided by wo axes: he average demand inerval

    and he squared coefficien o demand variaion. Years laer Boylan, Syneos,

    and Karakosas (2008) presened an applicaion o his mehod in a sofware

    firm. The iems consumpion patern is classified as srongly sporadic,

    slighly sporadic, and non-sporadic.

    The aim o his aricle is o analyze he patern o demand as he main

    inervening acor in invenory managemen. I firs o all discusses, in secion

    2, how he requenly adoped premises regarding he adherence o demand

    o Normal disribuion may no be realisic and cause disorions, especially

    in he case o very low when he annual demand is less han one and low

    consumpion iems when he annual demand ranges beween one and

    a value sufficienly high, say hree hundred or five hundred unis per year,

    in order o characerize a daily demand close o one. Secion 3 proposes a

    concepual ramework designed o suppor invenory managemen, which

    synhesizes hose models ha are mos adequae or specific paterns odemand (mean and variabiliy). Finally, secions 4 and 5 presen a case sudy

    underaken in a Brazilian company, which no only showed he pracical

    applicaion o he concepual ramework bu also revealed he laters impac

    in erms o shorage and excess coss.

    . Literature Review

    Choosing he mos adequae invenory managemen model is essenially an

    empirically-based decision ha may involve he use o simulaion, scenario

    analysis, incremenal cos analyses (Silva 2009; Rosa e al. 2010; Rego and

    Mesquia, 2011; Wanke 2011b) or qualiaive concepual schemes also known

    as classificaion approaches (Huiskonen 2001). The later usually considersha he impac o produc, operaion and demand characerisics consiue

    inervening variables in his choice (see, or example, Williams 1984; Hax and

    Candea 1984; Dekker, Klen, and De Roo 1998; Boter and Foruin 2000;

    Braglia, Grassi, and Monanari 2004; Eaves and Kingsman 2004; Wanke 2011b).

    An analysis o he lieraure dealing wih invenory managemen model

    selecion shows ha i originally ocused on producion and disribuion

    environmens in which demand and lead ime end o be more predicable

    or, in oher words, in which i is easier o answer he quesions o wha and

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL8

    how much o order (Wanke and Saliby, 2009; Wanke 2011b; Rosa e al. 2010).

    However, here is a growing lieraure relaed o he specific problems raised by

    low and very low consumpion iems such as spare pars (Boter and Foruin

    2000; Silva, 2009; Rego and Mesquia 2011; Syneos e al. 2012).

    The inrinsic characerisics o spare pars, which are ypically low and very

    low consumpion iems, make he choice o invenory managemen models

    paricularly criical under he ollowing circumsances (Cohen and Lee 1990;

    Cohen, Zheng, and Agrawal 1997; Mucksad 2004; Kumar 2005; Rego 2006):

    low sock urnover, difficul predicabiliy, longer replenishmen imes, greaer

    service level demands and higher acquisiion coss.

    Thereore, hese special eaures o spare pars deermine he selecion o

    appropriae invenory managemen models. According o Boter and Foruin

    (2000), here is a consensus ha spare pars canno be managed using radiional

    models (see, or example, hose presened in Rosa e al. 2010). Basically, spare

    pars do no fi hese models main premises such as, or example, he adherence

    o demand o symmeric and coninuous probabiliy densiy uncions (Silva 2009).

    The ollowing subsecions explore his issue a greaer deph, linking demand

    characerisics (mean and variabiliy) o invenory managemen models

    developed in he lieraure. In he case o average demand, he lieraure

    provides he basis or he segmenaion o annual consumpion according

    o hree differen levels very low consumpion, low consumpion and massconsumpion (Ward, 1978; Silva, 2009; Wanke, 2011a) while he coefficien o

    variaion (see or insance, Silver e al., 1998; Hopp and Spearman, 2008) and

    he probabiliy disribuion uncions (see or insance, Yeh, 1997; Silver e al.,

    1998) orm he basis or segmenaion in he case o variabiliy.

    . Very low consumption

    According o Tavares and Almeida (1983), very low consumpion pars are

    hose whose average consumpion is less han one uni per year. According o

    hese auhors, he sock conrol o hese iems should no be perormed using

    he usual models because, due o heir paricular consumpion characerisic,

    here are no enough previous occurrences o make a precise esimae oprobabiliy disribuion (Croson 1972; Syneos and Boylan 2001; Ghobbar and

    Friend 2003; Eaves and Kingsman 2004; Willemain, Smar, and Schwarz 2004;

    Regatieri e al. 2005; Hua e al. 2007; Guierrez, Solis, and Mukhopadhyay

    2008; Gomez 2008; Teuner and Duncan 2009).

    In addiion, ollowing Tavares and Almeida (1983), i is he analysis o oal shorage,

    excess and order placemen coss, given a cerain service level, ha makes i

    possible o deermine wheher a par should, or should no, be kep in sock, and a

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    VOLUME 49, NO. 1 9

    replenishmen reques made solely agains an order. Thus, a binary oal cos model

    was developed o suppor decision-making regarding wheher o keep one (1) or

    no (0) uni in sock based on wo supposiions: adherence o demand o Poisson

    disribuion and he possibiliy o placing an emergency order wih a lower han

    usual lead ime, whenever a shorage occurs. This model is presened in appendix 1.

    . Low consumption

    For he purpose o his aricle, low cos iems are hose wih a hisorical

    consumpion o beween 1 and 300~500 unis per year, which leads o an

    average daily demand close o one, as suggesed by Wanke (2005). As demand

    is no oo small o use he model proposed by Tavares and Almeida (1983),

    service level-relaed decisions such as he order poin and replenishmen

    level assume greaer imporance. Thus, he model, which is widely used in he

    lieraure, was considered o be he mos adequae (Rosa e al. 2010).

    More precisely, he model involves a coninuous review o sock levels and

    replenishmen orders are always placed whenever he sock posiion reaches

    he order poin s (Silver and Peerson 1985; Silver e al. 1998). In his case, a

    quaniy o replenishmen is used ha is sufficien o raise he sock posiion

    o poin S. Tha is, in pracice, he lo size is . According o Hadley and Whiin

    (1961), he models resul in uniary lo size orders when order placemen

    coss are low. Thus, as Feeney and Sherbrooke (1966) conclude, he policy

    consiues a paricular case o models.

    Various auhors (Feeney and Sherbrooke 1966; Walker 1997; Porras and Decker2008; Gomes and Wanke 2008) have used he model in spare par invenory

    managemen. Using his model, a replenishmen order is requesed as soon as

    a uni o sock is consumed in order o recompose he maximum level o sock.

    This model is appropriae or very cosly componens ha are essenial or

    business operaions (Walker 1997).

    In relaion o he probabiliy disribuions o demand and lead ime in he

    conex o models, Rosenshine e al. (1976 and Dhakar e al. 1993) iniially

    assume ha lead ime is deerminisic. However, various disribuions, have

    been considered in he conex o in order o represen he behavior o demand

    or lead ime separaely: Normal (Krupp 1997), Gama (Burgin 1975; Das 1976;Yeh 1997), Poisson (Hill, Omar, and Smih 1999) and empirical disribuion wih

    sochasic demands and lead imes (Eppen and Marin 1988).

    Anoher imporan poin involves he deerminaion o he probabiliy

    disribuion ha resuls rom he combinaion o lead-ime demand resuls

    (Lau 1989; Silva 2009). According o Tyworh (1992), heNormal disribuion

    consiues a reasonable approximaion or high consumpion iems, bu no or

    low consumpion ones. In he case o he later iems, disribuion is ypically

    asymmeric and possesses a high probabiliy o demand equal o zero. Porras

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL10

    and Decker (2008) adoped he Poisson disribuion o esimae he lead-ime

    demand o iems wih only one occurrence a each specific ime inerval.

    I should be highlighed ha when demand involves more han one

    occurrence per ime inerval, various auhors have proposed compound

    models, such as he Sutering Poisson (Ward 1978) , he compound

    Poisson model (Williams 1984; Silver, Ho, and Deemer 1971) or he

    compound Bernoulli model (Janssen, Heus, and Kok 1998; Srbosch,

    Heus, and Schoo 2000). More recenly, Syneos e al. (2012) conduced

    a comprehensive lieraure review on he disribuional assumpions

    or spare-pars managemen, assessing he goodness-o-fi o various

    disribuions and heir sock-conrol implicaions in erms o invenories

    held and service levels achieved.

    However, since mos o he disribuional assumpions are difficul o

    apply in pracice as he parameers o more han one disribuion mus

    be deermined firs so as o analyze he lead-ime demand behavior and

    in order o make he concepual ramework developed in his research

    operaional o managers, readily o be implemened in Excel spreadshees,

    we decided o narrow he decision regarding he mos adequae lead-

    ime demand disribuion beween Poisson and Gamma disribuions. For

    examples on he pracically o he implemenaion o hese disribuions in

    Excel, readers should reer, or insance, o Hopp and Spearman (2008) and

    Wanke (2011a) or Poisson disribuion and Silver e al. (1998) and Tyworhand Ganeshan (2000) or Gamma disribuion. Besides, as deailed nex,

    hese disribuions hold sraighorward relaions beween heir defining

    parameers and he mean and variance o he variable o ineres.

    ... Poisson Distribution

    In he case o low consumpion iems, Silver e al. (1998) sugges adoping

    he Poisson disribuion premise (c. Appendix 2). According o Yeh (1997 ),

    however, i is firs o all necessary o veri y he pracical applicabiliy o he

    Poisson disribuion. This is because, in he Poisson disribuion, he mean

    and variance are numerically equal. Thus, i his disribuion is o be used

    in pracice, he variance o demand mus be siuaed wihin an inervaldelimied by a variaion o en percen around is mean: 0.9ED

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    VOLUME 49, NO. 1 1

    Gamma disribuion adheres easily o real daa and can be mahemaically

    manipulaed in invenory managemen.

    Following Yeh e al. (1997), he Gamma disribuion is adequae in cases where

    periods wih null demand occur more requenly. Under hese circumsances,

    i makes sense o consider he ime inerval ha has elapsed beween wo

    consecuive demands differen rom zero as a variable o ineres or modeling

    purposes, besides demand isel and lead ime. Segersed (1994 and Yeh

    1997), or example, developed an invenory managemen model assuming ha

    he ime inerval beween wo consecuive non-zero demands (Ti), demand ()

    and lead ime (TR) are adheren o he Gamma disribuion.

    I is worh noing ha inermiten demand paterns meaning ha demand

    arrives inrequenly and is inerspersed by ime periods wih no demand a all

    is a criical or choosing he mos adequae disribuional assumpion (Eaves,

    2002; Syneos e al., 2012). Boylan and Syneos (2007) used he average

    demand inerval, ha is he mean ime beween wo consecuive demands

    greaer han zero, o classiy spare pars in conjuncion wih demand and lead-

    ime uncerainy. Eaves and Kingsman (2004) developed similar conceps.

    The model used by Yeh (1997) uses he probabiliy o no having a sock

    shorage during an order cycle, ha is, during he inerval o ime beween

    wo consecuive replenishmens, as a measure o he service level. The lowes

    and highes desired service levels or each iem are defined according o he

    model. The service level or he remaining sock is calculaed by 1-Ps(S), inwhich Ps(S), given in Appendix 4, is he probabiliy o sock shorage during he

    order cycle, given he level o sock S.

    . Mass consumption

    Mass consumpion iems are requenly considered o be hose wih a

    hisorical consumpion o over 300~500 unis per year, roughly one uni/day

    (Wanke2005). According o Rosa e al. (2010), he classic lo size/reorder poin

    model sands ou among mass consumpion iem invenory managemen

    models. According o his model, unis are requesed whenever he sock

    posiion reaches reorder poin (OP) (Love 1979; Silver e al. 1998; Mucksad

    2004; Sherbrooke 2004; Hopp and Spearman 2008). In pracice, he size o loQis deermined by he radiional Economic Order Quaniy ormula (Harris

    1913) and he reorder poin is defined so as o assure a specific service level

    measure (Eppen and Marin 1988; Rego e al. 2011).

    I is necessary o know he orma o he disribuion o lead-ime demand

    o deermine he saey sock embedded wihin he reorder poin (Keaon

    1995). According o Porras and Decker (2008), his calculaion requires

    speciying he disribuion o lead-ime demand so ha he saey acor, K,

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL12

    can be deermined. Tradiionally, lead-ime demand is modeled using a Normal

    disribuion (Silver and Peerson 1985). Due o he properies o his disribuion,

    he saey acor Kor a specific service level is he same as o he sandard

    normal disribuion curve, Z, which can be ound in several saisics and

    logisics exbooks such as, or example, Levine e al. (2005) and Ballou (2006).

    Various sudies, however, criicize his approximaion. According o Menzer

    and Krishnan (1988), his approximaion is only valid i he Normal disribuion is

    defined beween he inerval o -and +. Moreover, his creaes he possibiliy

    o negaive demand in many pracical applicaions. For Moors and Srbosch

    (2002), one o he main drawbacks o he Normal disribuion is he symmery

    assumpion. Furhermore, according o Eppen and Marin (1988), iems ha

    presen a Normal disribuion o lead-ime demand are ound in only a ew cases.

    As an atemp o balance he advanages and disadvanages o choosing an

    specific premise, Silver e al. (1998) propose a general rule or approximaing

    lead-ime demand using he probabiliy disribuion o he coefficien o

    variaion (CV), in he specific case o mass consumpion iems. I CVis greaer

    han 0.5, he Gamma disribuion should be used and, i i is no, a Normal

    disribuion provides a good approximaion or lead-ime demand.

    . CONCEPTUAL FRAMEWORK FOR INVENTORY MANAGEMENT

    Taking he heoreical ramework presened in previous secions as a poin o

    deparure, he presen aricle proposes a concepual ramework or invenory

    managemen based on he segmenaion o annual demand ino hreecaegories very low consumpion, low consumpion and mass consumpion

    and he coefficien o he variaion o demand ino wo caegories high

    uncerainy and low uncerainy. Using hese wo demand patern-associaed

    variables, he concepual ramework indicaes he mos appropriae invenory

    managemen model or low, very low, and mass consumpion iems, hus supporing

    decision-making based on he mos adheren premises o answer he quesions o

    how much o order, when o order and how much sock o keep in saey socks.

    In he concepual ramework synhesized in figure 1, exremely low

    consumpion iems are considered o be hose wih an average hisorical

    demand o less han one uni per year. Low consumpion iems correspond oiems whose average hisorical demand may vary beween one and 300~500

    unis per year, or a maximum o one uni per day, while mass consumpion

    iems are hose wih a demand o over approximaely 300~500 unis per year,

    in accordance wih Wanke (2005). The cu-off poin or he coefficien o he

    variaion o demand is 0.5, like in Silver e al. (1998).

    More specifically, or each quadran o annual demand and he iems

    coefficien o variaion o demand, he concepual ramework conains he

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    VOLUME 49, NO. 1 1

    mos adheren probabiliy disribuion uncions and he mos appropriae

    invenory managemen model, incorporaing all he heoreical consideraions

    described in he previous secions.

    FIGURE : CONCEPTUAL FRAMEWORK FOR INVENTORYMANAGEMENT

    In addiion o he developmen o concepual rameworks, Rego e al.

    (2011) sress he need o conduc case sudies ocusing on heir pracical

    applicabiliy in firms in order o overcome gaps beween heory and pracice.

    These case sudies enable researchers o increase heir pracical knowledge

    given ha aspecs involving undersanding abou environmens complexiy and

    he managerial effors made by firms become eviden. Examples can be ound in

    Cohen e al. (1990), Boter and Foruin (2000), Srbosch, Heus, and Schoo (2000),

    Trimp e al.(2004), Levn and Segersed (2004), Wanke (2005), Porras and Dekker

    (2008), Wagner and Lindemann (2008), Syneos, Keyes, and Babai (2009), and

    Silva (2009). The ollowing secions presen and discuss he resuls o he pracicalapplicaion o he proposed concepual ramework in a large Brazilian company.

    . PRACTICAL APPLICATION: DESCRIPTION OF RESULTS

    The concepual ramework presened in secion 3 ormed he basis or he

    developmen o a VBA ool or Excel o help segmen invenory iems using a

    daabase srucured in an elecronic spreadshee. In addiion, his ool makes

    i possible o obain a quick answer o he quesions o how much o order,

    when o order and how much sock o keep in a saey sock or a large number

    BinaryModels(Zero

    orOne)

    Coefficientofvariation

    ofdemand

    Lessthan

    0.5

    Great

    erthan

    0.5

    Annual Demand0 1 300~500 Infiniy

    Policy (Q, OP)

    Order Poin

    SS Gamma Disribuion

    or Daa Hisogram

    Order Poin

    SS Normal Disribuion

    or Daa Hisogram

    Policy (S, S-1)

    Shor Lead Time Lo = 1

    Lead Time Long

    Lo=Consunpion

    Forecase during Lead Time

    .Premises/Assumpions o

    Deermine S:

    Poisson

    If 0,9 E(D) < Var (D) < 1.1 E(D)

    Gamma

    If he percenage of periods

    during which D=0 exceeds

    30% of he oal

    Demand LT

    Replenishmen LT

    Average Demand

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL14

    o iems, considering a given level o service ha he firm wishes o offer

    cusomers and he previously idenified segmenaion. The ool was applied o

    real daa rom a Brazilian company in order o measure possible gains resuling

    rom he proposed concepual ramework or invenory managemen.

    The firm ha was he objec o his pracical applicaion is one o he worlds

    leading manuacurers o agriculural and consrucion equipmen. I has

    approximaely one hundred sixy acories worldwide, o which hree are

    locaed in Brazil. The Brazilian subsidiary has more han wo housand

    employees. In addiion, he firm mainains a oal o more han 20,833 differen

    iems in is Brazilian subsidiarys warehouses. The firm considers ha his

    diversiy o iems is undamenal or providing suppor or echnical assisance

    aciviies and pos-sales services or he equipmen i commercializes.

    In order o perorm a comparison beween he invenory managemen acually

    verified in he firm and he policy suggesed by he ool (concepual ramework),

    he sudy used consumpion daa o he previous ory-eigh monhs or all

    20,833 iems. Besides consumpion daa, oher daa inormed by he firm,

    which was imporan or modeling purposes, was also used: iems acquisiion

    cos; replenishmen/order placemen cos; unavailabiliy and penaly coss;

    average supplier lead ime; variance o supplier lead ime; opporuniy cos o

    mainaining socks or a year, or each o he differen iems.

    The firs sep in he applicaion o he concepual ramework was o use he

    Excel ool o segmen he iems according o he classificaion caegorieso very low consumpion, low consumpion and mass consumpion, which

    resuled in he ollowing respecive percenages: 22 percen; 74.5 percen

    and 3.5 percen. In addiion, based on he hree demand caegories and he

    wo coefficiens o variaion, an analysis was underaken o demands degree

    o adherence o he Poisson and Gamma disribuions, according o he

    discussion presened in secions 2.2.1 and 2.2.2.

    Figure 2 shows one o he ool s oupu screens conaining a sample o he

    firs en iems analyzed, heir respecive classificaion (very low consumpion,

    low consumpion and massconsumpion) and heir adherence o he mos

    adequae probabiliy disribuion (Poisson or Gamma). I should be highlighedha, as he adherence o demand o he Poisson or Gamma disribuion was

    no verified, i was assumed ha demand adhered o a Normal disribuion in

    cases in which he coefficien o variaion was lower han 0.5.

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    VOLUME 49, NO. 1 1

    All he analyses presened below relae o very low and low consumpion iems

    which represen 96.5 percen o oal iems.

    As regards very low consumpion iems, i was observed ha, in he case o 99.9

    percen o he iems classified in his group, he firm should keep a par in sock,

    oaling 4,586 socked iems (one or each iem). The invesmen needed o orm

    his sock exceeds BRL$2,540,000, i all pars have o be purchased iniially a he

    same ime, hus generaing an annual opporuniy cos o over BRL$563,000.

    In he case o low consumpion iems ha adhere o he Poisson or Gamma

    disribuions, he sudy calculaed he levels o sock needed o caer o hreedifferen service levels: a niny percen, niny-five percen, and niny-eigh

    percen probabiliy o no having a shorage o he iem in sock. For each level

    o service he sudy calculaed he opporuniy coss o keeping he pars in

    sock, as well he invesmen needed o purchase hese iems i hey iniially

    had o be purchased simulaneously.

    Specifically or he niny percen level o service, an invesmen o over

    BRL$84,000,000 would be needed o orm his sock i all pars iniially had o be

    FIGURE : RESULTS OUTPUT SCREENSEGMENTATION ANDADHERENCE TO THE DISTRIBUTION

    ID Item Code Classification Poisson Gama

    1 A1304031 Low Turnover no yes

    2 A162896 Very Low Turnover no no

    3 BNHCMP0001 Low Turnover no yes

    4 BNHCMP0002 Mass Consumpion no no

    5 BNHCMP0005 Mass Consumpion no no

    6 BNHCMP0007 Mass Consumpion no no

    7 BNHC0001 Low Turnover no yes

    8 BNHC0002 Low Turnover no yes

    9 BNHC0003 Low Turnover no yes

    10 BNHC0004 Mass Consumpion no no

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL16

    purchased simulaneously. This amoun involves an annual opporuniy cos o

    BRL$18,670,000.00. This opporuniy cos o roughly weny-wo percen per year

    is basically financial: i relaes o he high ineres raes o he Brazilian economy.

    By he ime he case sudy was conduced (2010), he Brazilian base ineres

    rae, named SELIC, was around welve percen per year. These addiional en

    percen poins consiue he average spreads incurred by large companies when

    borrowing money o suppor working capial requiremens, such as invenories.

    On average, en pars are kep in sock or each low consumpion iem.

    . PRACTICAL APPLICATION: DISCUSSION OF RESULTS

    As he company did no divulge is real invenory policy nor wheher radiional

    invenory classificaion schemes, such as ABC, subsidized decision-making

    wih respec o invenory model segmenaion, he sudy made some working

    assumpions in order o be able o evaluae wheher gains would occur in

    boh financial and service level erms i he invenory models suggesed by

    he concepual ramework were adoped. Some o hese working assumpions

    considered he Normal disribuion alogeher wih (S, s)invenory model and

    coninuous review or low and very low consumpion iems.

    For very low consumpion iems, he sudy analyzed he impac, in erms o

    oal coss, o keeping no (CT0) or one (CT1) par in sock, as shown by eqs. (A1)

    and (A3), respecively. The resuls showed ha he mos appropriae policy was

    o keep a par corresponding o each iem in sock as i led o a gain given

    by he sum o he differences (CT0-CT1) or all iems o BRL$14,429,517.56.The gains ha can be achieved by keeping a par in sock or all iems are due

    mainly o he high unavailabiliy and penaly coss, which hus consiue an

    exremely imporan par o he cos difference beween he wo policies.

    In he case o low consumpion iems, which represen 74.5 percen o he oal,

    he sudy considered ha he arge-sock S or each iem was equal o he

    mean o he hree bigges demand spikes ha had occurred during he previous

    ory-eigh monhs. This is a common pracice wihin Brazilian companies

    (c. case sudy in Wanke 2011). Then, or each iem, he sudy calculaed he

    opporuniy cos or he level o sock suggesed by he ool and he one

    effecively praciced by he firm. When he resuling difference was posiive,

    i was considered ha he adopion o he concepual ramework would leado a reducion in opporuniy coss. In his case, his amouned o nearly

    BRL$8,870,000, due o lower levels o invenory. Similarly, when he difference

    was negaive, he sudy assumed ha here would be an increase in opporuniy

    coss due o he rameworks adopion which, in his case, oaled nearly

    BRL$2,230,000, on accoun o higher levels o invenory. I should be poined ou

    ha, on mos occasions, he increase in invenory levels can be atribued o he

    need o adjus cusomer service levels, sipulaed, in his case, a niny percen.

    Wih he aim o ideni ying he oal ime aken o achieve financial gains

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    VOLUME 49, NO. 1 1

    resuling rom invenory demobilizaion, he sudy esimaed he amoun

    o ime needed o consume excess invenory, based on average monhly

    consumpion figures. The BRL$8,870,000 reducion in opporuniy coss is

    achieved wihin a maximum imescale o 20.57 monhs, bu in a maximum o

    six monhs i is possible o atain BRL$8,446,990.04, or 97.01 percen o he

    oal, and in a litle under a year, more precisely in 10.29 monhs, i is possible

    o achieve 97.89 percen o gains, amouning o BRL$8,676,001.41 (figure 3).

    The ool, which idenified he adherence o he disribuions o low urnover iems o

    he Poisson and Gamma disribuions, showed grea efficiency, producing savings o

    BRL$2,321,674.55, o be achieved over a maximum period o 20.57 monhs.

    FIGURE : Reduction Of The Opportunity Cost Of Maintaining

    Stocks Over Time.

    . CONCLUSIONS

    A vas lieraure relaed o invenory heory has been developed over he pas

    fify years. However, many o he heoreical resuls achieved are no easily

    applicable in business pracice, given ha mos are based on premises ha

    are no verified in he corporae environmen. Wih he aim o helping o fill

    his gap, his sudy proposes a concepual ramework designed o suppor he

    choice o he mos adequae/appropriae invenory managemen model.

    Based on differen demand characerisics, he proposed concepualramework reveals ha he premise ha demand adheres o Normal

    disribuion is no always valid and ha oher probabiliy disribuions, such as

    he Poisson and Gamma disribuions, should be considered by managers. This

    sudy also explored issues relaed o he managemen o socks o low and

    very low consumpion iems hrough he rameworks pracical applicaion in a

    Brazilian agriculural and consrucion equipmen company.

    A

    ccumulatedGain(BRLthousand)

    Achievement Time (months)

    0 5 10 15 20

    2500

    5000

    7500

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL18

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    APPENDIX DERIVATION FOR VERY LOWCONSUMPTION

    ITEMS (TAVARES AND ALMEIDA )

    The auhors demonsraed ha he oal cos associaed wih he policy o no

    keeping a spare par in sock (CT0 ) can be calculaed as ollows:

    (A1)

    in which is he average hisorical consumpion (pars/year), CTR is he oal

    cos o iem replenishmen/order placemen (BRL), and Cipis he cos o

    unavailabiliy and penaly coss relaed o shorage (BRL).

    In order o adop he alernaive policy, ha is, he firm keeps a uni in sockunil consumpion occurs, an evaluaion should be perormed o he expeced

    racion o ime in sock (FTECE), given by:

    (A2)

    in which TRis he replenishmen lead-ime.

    The expeced value o occurrences during he expeced racion o ime ou o

    sock is given by *(1-FTECE). Thus, one can obain he oal cos associaed

    wih he decision o always keep a par in sock (CT1 ), aking ino accoun he

    possible occurrence o anoher reques during he lead ime, as well as is

    implicaions in erms o replenishmen coss and unavailabiliy and penaly

    coss, as given below:

    (A3)

    The pars o eq. (A3) represen, respecively, he opporuniy cos o keeping a

    spare par in sock, he oal replenishmen cos and unavailabiliy and penaly

    coss. In order o define he mos advanageous policy, i is necessary o

    compare he magniudes o CT0 and CT1, oping or he leas-cos decision.

    CT1= *Caq*i Cip**1+TR1 +[CTR*]+ 1+*TR

    1

    CT0=*(CTR+Cip),

    FTECE= ,1+*TR

    1

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL24

    INTEGRATING FMEA WITH THE SUPPLY CHAIN

    RISK MANAGEMENT PROCESS TO FACILITATE

    SUPPLY CHAIN DESIGN DECISIONS

    V. M. Rao Tummala

    Computer Information Systems Department, College of Business, Eastern

    Michigan University, Ypsilanti MI 48197

    Tobias Schoenherr, CSCP (Corresponding Auhor)

    Department of Supply Chain Management, Broad College of Business,

    Michigan State University, East Lansing MI 48824

    Thomas Harrison

    Chief Executive Officer, Michigan Ladder Company, Ypsilanti MI 48198

    ABSTRACT

    We presen a novel approach o inegraing ailure mode and effec analysis

    (FMEA) wih a supply chain risk managemen process (SCRMP). Focusing on

    he challenging ask o assess and manage supply-side risks in global supply

    chains, he approach developed offers an effecive and affordable way or

    firms o provide decision suppor or he selecion o heir mos appropriae

    supply chain design. The aim o he inegraed approach combining he

    srenghs o FMEA and SCRMP is o gaher as much perinen inormaionas possible, o srucure i, and o comprehensively delineae all poenial

    supply chain risk acors, offering valuable decision suppor. We illusrae

    he applicaion o he approach a Michigan Ladder Company, where i was

    applied o wo specific supply chains or he procuremen o fiberglass ladders.

    Specifically, one supply chain spanned rom China o he U.S. via Mexico

    (aking advanage o a Mexican maquiladora), and one spanned rom China

    direcly o he U.S. The combinaion o FMEA and he SCRMP enhanced he

    manuacurers confidence in is supply chain design decision, and enabled he

    firm o proacively manage is supply-side risks. Overall, he aricle is mean o

    moivae praciioners o embark on he journey o acive risk managemen.

    While some may perceive risk managemen as a dauning ask or beingprimarily employed by larger firms, we provide guidance or firms o any size

    o apply he approach i can be done, and does no have o consume an

    inordinae amoun o resources.

    Keywords: supply chain risk managemen, supply-side risks, ailure mode and

    effec analysis (FMEA), supply chain managemen decisions, case sudy

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    VOLUME 49, NO. 1 2

    Introduction

    Globalizaion has enabled companies o ake advanage o worldwide supply

    and demand markes, creaing new opporuniies and increasing heir profi

    poenial. However, wih hese enicing prospecs have also come he dangers

    o associaed longer and more complex supply chains (Tang 2006), which ofen

    span muliple counries or even coninens. Especially in a ime o increasing

    cusomer demands and requiremens on qualiy, delivery lead ime and

    responsiveness, managing hese global supply chains has become a challenge.

    Ensuing risks are hus muliarious, and can manies hemselves in he orm

    o supply disrupions or breakdowns (e.g., Hendricks and Singhal 2005; Sockes

    2008; Tang and Musa 2011). This is especially heighened in imes o companies

    ocusing on heir core compeencies, and ousourcing he remaining asks,

    ineviabiliy increasing heir vulnerabiliy (Narasimhan and Talluri 2009).

    Evidence is provided or example by he caasrophes associaed wih super-

    sorm Sandy on he Eas Coas o he U.S. in 2012, he floods in Thailand in

    2012, and he Japanese sunami in 2011. Besides he incomprehensible human

    ragedies, he later even or example also resuled in companies such as

    Apple, Sony Ericsson, and many auomobile manuacurers being unable o

    quickly adjus heir supply chains; he firms were unable o compensae or he

    missed supplies rom Japan, resuling in significan losses (BBC 2011). Furher

    examples o imminen risks abound, such as he financial crisis affecing mos

    companies and counries (Blome and Schoenherr 2011), as well as recen

    poliical insabiliy and regime changes (Doukas e al. 2011).

    Due o hese realiies, i has become an imperaive or odays supply chain

    managers o ideniy possible risks affecing heir supply chains, evaluae

    hem, and develop appropriae risk miigaion sraegies. However, his

    underaking can be a dauning ask (Kwak and Soddard 2004), as was

    revealed in a survey by Snell (2010): while 90 percen o he responding firms

    el hreaened by supply chain risks, ew el confiden and knowledgeable

    in managing hese risks. This finding is consisen wih our own anecdoal

    observaions and recen ineracions wih supply chain proessionals. As such,

    no many firms are employing a srucured approach o assess and manage

    risks inheren in heir global supply chains, which is especially he case or

    small- and medium-sized enerprises. This negligence can however havesevere repercussions, since even smaller firms and heir supply chains are now

    ofen inerconneced globally and hus exposed o a muliude o risks.

    I is hereore our objecive in he presen paper o illusrae a novel approach

    combining ailure mode and effec analysis (FMEA) wih a supply chain risk

    managemen process (SCRMP). This inegraed mehodology provides

    guidance or managers on how o beter ge a handle on risks associaed

    wih heir exising or poenial supply chain designs. The aim o he approach

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL26

    combining he srenghs o FMEA and SCRMP is o gaher as much perinen

    inormaion as possible, o srucure i, and o comprehensively delineae all

    poenial supply chain risk acors. We illusrae his applicaion a Michigan

    Ladder Company (MLC), which uilized he inegraive approach o provide

    decision suppor or is supply chain design. The mehodology srucured

    he decision problem and offered he firm more confidence in is final choice.

    The approach was applied o assess he supply-side relaed risks inheren in

    wo alernae supply chain designs or he procuremen o fiberglass ladders.

    While one supply chain design involved he procuremen o he finished

    produc rom China, he oher involved he procuremen o pars rom China,

    assembling hem in a Mexican maquiladora, and hen shipping hem o he

    U.S. locaion o MLC. The risks associaed wih each were assessed relaive

    o he firms objecives o cos reducion and responsiveness. Wihin his

    conex, supply chain risk was defined as he hrea or probabiliy o supply

    chain disrupions ha adversely affec he smooh flow o producs, impacing

    operaional perormance measures such as responsiveness and cos.

    The developmen and illusraion o he approach is imporan boh rom

    a pracical and a heoreical perspecive. From a pracical angle, he value

    consiss o he presenaion o an effecive, comprehensive, and inegraed

    ramework or risk managemen, consising o boh FMEA and he SCRMP,

    as well as an illusraion o how i can be applied. The imporance inheren

    in he later is he demonsraion ha risk managemen does no have o be

    rocke science or hugely expensive, and ha sraighorward approachescan yield significan insigh. I is hus our hope ha he aricle provides an

    impeus, moivaion and guidance or pracicing managers o ollow his

    ramework, especially also or small- and medium-sized firms, which may have

    been hesian o adop risk managemen approaches in he pas due o heir

    poenial associaed expenses and effor. We are also direcly addressing

    a shorcoming menioned in Snell (2010), who ound in heir survey ha

    respondens did no eel confiden and knowledgeable in managing hese

    risks. The approach presened herein is a means o increase confidence and

    knowledge in risk managemen, and represens a ready-o-use ool o beter

    manage global supply chain risks.

    The sudy also conribues o lieraure and heory in supply chain risk

    managemen in ha i proacively idenifies and evaluaes risk and miigaion

    sraegies, insead o examining ex pos scenarios (c. Trkman and McCormack

    2009); his leads o he urher improvemen o he firms confidence in is

    supply chain design ex ane, anicipaing poenial ailures and developing

    prevenive and response acion plans. The successul experiences made by

    Michigan Ladder Company demonsrae he useulness o he approach and

    is significan poenial in aciliaing supply chain decisions ocusing on risk

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    VOLUME 49, NO. 1 2

    assessmen and managemen. We hus also answer he call or urher insigh

    ino risk managemen approaches o aciliae and srucure supply managers

    sraegic decision making on he opimal configuraion o heir supply chains

    (Zsidisin e al. 2004). In addiion, we ollow he example o Chan e al. (2012),

    who encouraged he inegraion o FMEA wih risk analysis approaches. As

    such, overall, we make imporan conribuions o boh pracice and heory/

    lieraure in producion and operaions managemen.

    The nex secion provides a brie inroducion ino he general area o supply chain

    risk managemen. This is ollowed by a descripion o he inegraive approach

    combining FMEA and he SCRMP. Michigan Ladder Company and he conex in

    which he approach was implemened are presened nex. This is ollowed by he

    applicaion o our suggesed approach a MLC. The ensuing secion discusses he

    resuls, illusraes he derived value or MLC, and describes he acions resuling

    rom he approach. A las secion concludes he aricle.

    Supply Chain Risk Management

    We define supply chain risk as he hrea or probabiliy o supply chain

    disrupions ha adversely affec he smooh flow o producs, impacing

    operaional perormance measures such as responsiveness and cos.

    This definiion was derived rom exan lieraure, bu was also specifically

    influenced by he conex o MLC and how i viewed supply chain risk.

    Mos definiions ound in lieraure go back o he concepualizaion offered

    by he Briish Sandards Insiue, which described risk as a combinaion oprobabiliy or requency o occurrence o a defined hazard and magniude o

    occurrence (BS 4778, 1991). O paricular relevance in he presen sudy is he

    risk o inerruped supply. Wihin his conex, supply risk has been defined

    as ailures associaed wih inbound goods and services ha affec he firm

    o mee cusomer demand (Zsidisin e al. 2004, 2005). Similarly, Harland e

    al. (2003), reerring o Meulbrook (2000), described supply risk as adversely

    affecing inward flow o any resource ha hinders scheduled operaions. Our

    concepualizaion is in line wih hese prior definiions.

    The criicaliy o ensuring he smooh flow o producs hrough he supply

    chain and he impac o supply chain disrupions has been highlighed byrecen evens. For example, supply chains have been impaced by naural

    disasers, such as he super-sorm Sandy on he U.S. Eas Coas in 2012, floods

    in Thailand in 2012, he Japanese sunami in 2011 (Dawson 2011), he 2006

    earhquake in Java, he hurricanes Karina and Ria in 2005 (Devlin 2005), and

    he ongoing hackings o vessels by piraes off he coas o Somalia (Bowman

    2010). The immediae impac o announcemens concerning such supply

    chain disrupions on shareholder value has been shown by Hendricks and

    Singhal (2005). I is hereore crucial or managers o ideniy and undersand

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL28

    he associaed risks wih heir supply chains, as well as o hen develop risk-

    reducion sraegies (Chopra and Sodhi 2004).

    Responding o hese realiies, academic research ino supply chain risk

    managemen has flourished. For example, Waers (2011) ocused on supply

    chain risk managemen rom he perspecive o logisics, and Sodhi and

    Tang (2012) called or companies o more proacively manage he associaed

    risks. Frsl e al. (2011) repored on wha represens excellence in supply

    risk managemen across differen indusry secors, and Olson (2012) offered

    analysis ools or supply chain risk managemen. Allen and Schuser (2000)

    examined risk managemen a Welchs, Inc., or heir harvesing o grapes,

    and Maneti (2001) emphasized he imporance o r isk managemen or

    he choice and implemenaion o echnologies in manuacuring. Risk

    managemen was described as an essenial ingredien or projec planning

    by De Reyck (2010). Pohl e al. (2010) summarized exan lieraure in supply

    chain risk managemen, complemening earlier work by Tang (2006) who

    ocused on he review o quaniaive models or he managemen o supply

    chain risk. A review o recen sudies in supply risk is also provided in Blome

    and Schoenherr (2011).

    Various approaches have been suggesed or he managemen and miigaion

    o supply chain risks. As such, Kilgore (2004) inroduced an analyical

    risk miigaion ramework consising o five seps, Giannakis and Louis

    (2011) proposed a muli-agen decision suppor sysem or supply chainrisk managemen, and Wagner and Nesha (2010) assessed supply chain

    vulnerabiliy using graph heory. De Waar (2006) developed an inormal

    assessmen ool o implemen risk miigaion sraegies, Sheffi and Rice

    (2005) used he dimensions o disrupion probabiliy and consequences

    as caegorizaion scheme, and Kleindorer and Saad (2005) proposed a

    ramework reflecing he aciviies o risk assessmen and risk miigaion.

    Sinha e al. (2004) suggesed a prescripive risk mehodology applied o

    he aerospace supply chain, Cucchiella and Gasaldi (2006) proposed a real

    opions-based supply chain risk managemen approach, and Huhn and Kahn

    (2012) uilized robus opimizaion o manage supply chain risks. We build

    on and exend his sream o research and propose a novel and innovaivesupply chain risk managemen approach, which will be described nex.

    FMEA and SCRMP

    In our inegraed approach we combine he srenghs o radiional FMEA

    (1995), and uilize i ogeher wih specific echniques such as he U.S. Miliary

    Sandard 882C and he Hazard Toem Pole (Grose 1987), as par o he SCRMP.

    Wihin his conex, FMEA enables he assessmen o poenial ailures and

    heir effecs, ogeher wih he developmen o prevenive acion plans and

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    VOLUME 49, NO. 1 2

    associaed implemenaion coss, effecively complemening he SCRMP.

    A recen sudy illusraed he power o inegraing FMEA wih general risk

    managemen approaches, noed he dearh o research in his area, and

    hus called or he urher invesigaion o his area (Chan e al. 2011). Chan

    e al. (2011) specifically noed ha here is a lack o pracical guidance in he

    inegraion o risk and ailure analysis, and sressed he significan poenial o

    doing so. We answer his call in he presen sudy.

    The value o inegraing FMEA wih oher approaches can be considerable,

    given exan research ha repored on such inegraion effors. For example,

    Shahin (2004) inegraed FMEA wih he Kano model, Chang and Paul (2009)

    combined FMEA wih daa envelopmen analysis, and Chin e al. (2009)

    inegraed i wih he evidenial reasoning approach. In he presen sudy, we

    inegrae FMEA wih he supply chain risk managemen process and illusrae

    is combined applicaion.

    Failure Mode and Effect Analysis (FMEA)

    Failure mode and effec analysis (FMEA) is a srucured approach o ideniy

    and preven produc and process ailures beore hey occur (McDermot e

    al. 2009). Having evolved rom firs applicaions in he aerospace indusry in

    he 1960s, i has since hen been widely employed or produc and process

    improvemen effors and or he purpose o reducing he risk o ailures

    (Samais 2003). In FMEA, every possible maluncion or breakdown is

    assessed in erms o he poenial causes o he ailure, he poenial effecsand consequences, prevenive acions possible, and coss o hese prevenive

    acions (Taikonda and Taikonda 1994). FMEA has been applied or example

    o projec risk managemen (Tummala and Mak 2001; Ng e al. 2003; Carbone

    and Tippe 2004) and o he implemenaion o enerprise resource planning

    sysems (Shirouyehzad e al. 2011). I was also noed ha benefis rom FMEA

    are mos ully realized i i is par o a qualiy managemen sysem (McDermot

    e al. 2009). Exending his idea, we orward he noion ha he applicaion o

    FMEA ogeher wih he SCRMP is mos effecive.

    While mos FMEA sudies have ocused on produc and manuacuring

    process improvemens, and no on supply chain managemen, he inherenineres o hese prior sudies was in reducing he risk o produc or process

    ailures (Samais 2003). Wha is hereore imminen is he applicabiliy o

    supply chain risk managemen. Wih a ew excepions, however, exan

    research has no deal wih he applicaion o FMEA o supply chain risk

    managemen, an observaion which suggess o have lef many opporuniies

    on he able. Wihin he conex o supply chain managemen, Elkins e al.

    (2005) proposed using FMEA o race back he roo cause o a ailure and learn

    rom he even, and Teng e al. (2006) provided guidance or implemening

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL30

    FMEA in a collaboraive supply chain environmen. We exend hese works by

    illusraing he combined applicaion o FMEA wih he SCRMP.

    Supply Chain Risk Management Process (SCRMP)

    The Supply Chain Risk Managemen Process (SCRMP) is a ramework or he

    assessmen o he risk profile associaed wih a specific supply chain, and

    was concepually developed by Tummala and Schoenherr (2011). I offered

    a pracical emplae o manage supply chain risks more effecively in a

    srucured ashion. However, he auhors ailed o illusrae he approach

    in he real world, quesioning is applicabiliy and relevance or managerial

    pracice. In he curren research, we work owards alleviaing his omission,

    and inegrae i wih FMEA.

    The core o he SCRMP consiss o hree phases: (I) risk idenificaion, risk

    measuremen and risk assessmen, (II) risk evaluaion, risk miigaion and

    he developmen o coningency plans, and (III) risk conrol and monioring

    (Tummala and Schoenherr 2011). The purpose o phase I is o enumerae all

    possible poenial supply chain risks, and assess heir severiy and likelihood o

    occurrence. Phase II evaluaes he idenified risks o develop appropriae risk

    response sraegies or risk reducion and managemen. Phase III develops a

    risk-based daa managemen and analysis sysem o monior he effeciveness

    o he implemened risk reducion plans.

    In he curren sudy we ocus on phases I and II o he SCRMP, heir inherenprocess seps, associaed echniques and evaluaion approaches. Specifically,

    he seven process seps ha we consider are he ollowing: (1) ideniy

    poenial supply chain risk acors; (2) assess he severiy o consequences

    o he idenified risk acors; (3) assess he likelihood o occurrence o he

    idenified risk acors; (4) classiy he idenified risk acors; (5) deermine he

    cos o implemening risk response acion plans; (6) deermine risk prioriy

    scores; and (7) consruc he Hazard Toem Pole char. The las phase and

    remaining process seps no considered reer o acions aken afer he risk

    miigaion and coningency plans have been implemened, and deal wih

    ongoing risk conrol and monioring. These seps are no considered since

    hey are ouside o he scope peraining o he inegraion o FMEA; raher,hey uilize resuls o he prior seps and FMEA o effecively manage risk.

    CONTEXT AND BACKGROUND

    We illusrae he applicaion o our approach a Michigan Ladder Company

    (MLC), a small manuacurer and disribuor o ladders, locaed in Ypsilani,

    Michigan. The produc specrum o MLC is narrow bu deep, including

    aluminum, fiberglass and wood ladders. The firm has been enjoying good

    financial healh despie he economic downurn, providing evidence o is

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    VOLUME 49, NO. 1 3

    sound risk managemen approaches. Esablished in 1901, MLC is he oldes

    U.S. ladder manuacuring company, supplying ladders primarily or he

    commercial secor, including he miliary. The coninued success o he

    company is atribued o is innovaive and loyal workorce, as well as MLCs

    emphasis on and dedicaion o qualiy producs. The firm was chosen o serve

    as an exemplar or he applicaion o our approach, since i had been very

    proacive in is houghs oward risk managemen.

    An earlier approach o risk managemen ha he company was aking,

    involving he analyic hierarchy process (AHP), was chronicled in Schoenherr

    e al. (2008). This evaluaion was riggered by changes in he compeiive

    landscape and he wish o move he sourcing o wo o he firms major

    produc lines rom a Mexican supplier o an alernae source. The five

    alernaives considered were (1) he sourcing o finished goods rom Mexico, (2)

    he sourcing o finished goods rom China, (3) he sourcing o pars rom China

    and assembly in he U.S., (4) he sourcing o pars rom China, assembling

    hem in a maquiladora in Mexico wih invesmen, and (5) he sourcing o

    pars rom China, assembling hem in a maquiladora in Mexico wih no

    invesmen. These supply chain designs and associaed sourcing locaions

    were considered due o heir appeal in erms o boh qualiy and cos, which all

    alernaives demonsraed. A oal o seveneen risk acors were idenified as

    being relevan or he firm. Using AHP modeling, he risk acors were assessed

    across he five alernaives, yielding a preerence score minimizing he risks

    or each alernaive. As a resul, he hree alernaives wih he leas risk wereimplemened (alernaives (2), (5) and (1)). Three supply chain designs were

    pursued, so as o urher diversiy he risk inheren in each. This approach

    has been receiving grea ineres by praciioners, and was also eaured

    a a dinner presenaion held or he Greaer Deroi Chaper o APICS. We

    hereore conaced MLC o solici is paricipaion or he presen sudy.

    Due o he dynamic environmen, MLC was consanly re-evaluaing is

    sraegic choices regarding is ousourcing aciviies. A he ime he sudy

    was conduced, he company had abandoned alernaive (1), which was merely

    reained unil he new supply chain designs were ully operaional. As such,

    he company was operaing wih wo supply chain designs: (A) he sourcingo finished goods rom China, and (B) he sourcing o pars rom China,

    assembling hem in a Mexican maquiladora (wih no invesmen aken in he

    venure), and hen shipping hem o he Midwes locaion o he firm. We will

    reer o opion (A) as he China-Midwes supply chain, whereas opion (B) is

    reerred o as he China-Mexico-Midwes supply chain.

    Alhough hese wo supply chains represened he leas risk, based on he

    prior AHP analysis, qualiy problems began o emerge abou a year afer he

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL32

    commimen o he China-Midwes supply chain had been made. A more

    deailed invesigaion o he risk acors involved in his supply chain was

    hereore needed, offering a ormidable conex o apply FMEA inegraed

    wih he SCRMP. In order o provide a comparison benchmark, i was

    decided o also include he second leas-risky alernaive in he evaluaion,

    he China-Mexico-Midwes supply chain, which had also been in operaion.

    The design, srucure and configuraion o hese wo supply chains is quie

    diverse, involving a differen se o supply chain risks and differing inensiy

    levels or each. As such, a more rigorous assessmen o hese wo scenarios

    was now warraned. In addiion, in conras o he earlier evaluaions via AHP,

    he wo supply chains were now ully operaional, and acual experiences

    had been made o beter gauge he risks. Thereore, in collaboraion wih he

    company, he approach presened herein was developed, combining FMEA

    and he SCRMP. The goal was o aciliae he decision on he opimal supply

    chain design, minimizing supply-side relaed risks. The overriding objecives

    o he assessmen were o reduce coss along he supply chain, wih

    however a he same ime improving (or a leas no deerioraing) service

    levels and responsiveness.

    Differentiation to Prior Work

    The curren work builds on and exends prior sudies, and we would like o

    highligh how he curren paper differeniaes isel. Specifically, above we

    noed ha we are ollowing up on a decision Michigan Ladder Company had

    made peraining o five offshoring alernaives, which was aciliaed wihhe Analyic Hierarchy Process and presened in Schoenherr e al. (2008).

    Our work differeniaes isel in ha we are no relying on AHP o offer

    decision suppor. While we conduced our research a he same company

    wih he same risk acors (since hese risk acors were sill deemed valid by

    he company), he ramework presened in he presen paper is differen in

    ha we apply a novel approach inegraing FMEA and he SCRMP.

    In addiion, he presen paper describes an approach or decision suppor

    ha was aken laer on in he imeline o he company, once he decision

    chronicled in Schoenherr e al. (2008) had been made. As such, we are

    ocusing on he wo leas risky alernaives idenified in Schoenherr e al.(2008) , and provide more enhanced and deailed decision suppor, building

    on and exending his prior work. Furhermore, we base he assessmen

    on he acual operaion o he wo supply chains, or boh o which

    experiences had now been made. Moreover, even hough we consider

    he same seveneen risk acors as hose idenified by Schoenherr e al.

    (2008) , he use o FMEA and he applicaion o he principles inheren in he

    SCRMP, such as he U.S . Miliary Sandard 882C and he Hazard Toem Pole,

    enabled us o provide a much more deailed analysis o assess he poenial

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    PRODUCTION AND INVENTORY MANAGEMENT JOURNAL34

    INTEGRATING FMEA WITH THE SCRMP: AN APPLICATION AT MLC

    This secion describes he inegraion o FMEA wih he SCRMP, as well as how

    i was applied a MLC. Table 1 provides a summary o his inegraion. Overall,

    his expos provides a valuable applicaion and emplae or oher firms acing

    similar problem scenarios and decisions.

    TABLE :INTEGRATION OF SCRMP AND FMEA

    Step Step in the SCRMP Integration with FMEA

    1 Idenify risk facors

    Define he poenial failure mode (i.e. how he specific risk manifess

    iself in erms of failures or breakdowns for MLC), poenial causes of

    he failure or breakdown, poenial effecs or consequences of he

    failure or breakdown, prevenive acions ha could be done, and he

    cos of such acions

    2 Assess he severiies of consequencesUpdae (add or modify) he FMEA framework by more deailed

    informaion having emerged hrough his SCRMP sep

    3 Assess he likelihood of occurrenceRefer o informaion colleced in he FMEA o make more informed

    decisions on he assignmen of individual likelihood values

    4 Classify he idenified risk facorsRefer o informaion colleced in he FMEA o subsaniae

    classificaion; if necessary, make adjusmens o beter reflec realiy

    5Deermine he cos of implemening risk

    response acion plans

    Provide more deail in he FMEA framework peraining o specific

    coss, as well as subsaniaion for specific cos esimaes

    6 Deermine risk prioriy scores

    Subsaniae he classificaion ino risk prioriy scores wih

    qualiaive informaion recorded in he FMEA, combining he

    srenghs of boh approaches

    7 Consruc he Hazard Toem Pole char

    Uilize informaion from he FMEA framework o subsaniae

    classificaions and overall srucure of he Hazard Toem Pole, refuing

    he criicism ha SCRMP scores can be subjecive; his can be

    especially useful in he presenaion o ohers affeced by he decision

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    Step 1: Identify Risk Factors

    We commenced wih he firs sep o he SCRMP, i.e. he idenificaion o

    supply chain managemen risk acors. Useul approaches a his sage

    include brainsorming or he nominal group echnique. All easible risks should

    be idenified ha could poenially influence he desired oucomes. The

    overriding objecives o he risk assessmen in he case o MLC were o reduce

    coss along he supply chain, wih however a he same ime improving (or a

    leas no deerioraing) service levels and responsiveness. These objecives

    were kep in mind when considering poenial supply-side risk acors or MLC.

    Afer a review o poenial risks, he research eam deemed he seveneen

    risk acors as idenified earlier (Schoenherr e al. 2008) as sill represening

    he curren siuaion. Furher discussions and eedback obained rom

    colleagues no involved in he research and in oher uncions did no lead o

    any addiional applicable acors. These seveneen risk acors, as well as heir

    definiions and corresponding abbreviaions used in he ensuing discussion,

    are summarized in Table 2.

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    TABLE :IDENTIFIED RISK FACTORS

    Risk

    Factor

    Code

    Risk Factors Label Risk Factor Definitions

    ACR ANSI ComplianceMinimum requiremens ha he companys producs mus a leas fulfill, and he risk ha he

    supplier fails o mee hese requiremens.

    PQR Produc QualiyLikelihood of he supplier no providing an excellen produc in erms of qualiy (measured in

    erms of he number of defecive producs).

    PCR Produc Cos Price ha he company pays for he produc, and he risk associaed wih a price increase.

    CCR Compeior Cos

    A measure of how he price ha he company receives from is suppliers compares o he price

    compeiors are likely o pay for comparable inpu. I represens he risk of he compeior having a

    relaive cos advanage.

    DMR Demand RiskMeasures he likelihood of severe swings in demand, and he responsiveness he respecive

    supply chain would exhibi in accommodaing hese swings.

    SFR SupplierFulfillmen Risk

    Esimaes how accurae suppliers are fulfilling he orders, boh in erms of qualiy, quaniyand puncualiy.

    LGR Logisics RiskRisks due o organizaional aspecs of logisics, such as paperwork involved, scheduling roues,

    deermining wha o ship wih wha mode and a wha ime, selecion of pors and carriers, ec.

    TBROn-Time and

    On-Budge Risk

    Deals direcly wih he abiliy of he supplier o deliver he produc o he company on-ime

    and on-budge, i.e. wihou delays and wihou any higher coss.

    OFROrder Fulfillmen

    Risk Addresses he risk ha producs ordered are no delivered in he quaniy and qualiy demanded.

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    WPRWrong Parner

    Risk

    Risk of engaging wih he wrong parner, and hus, due o heir poenial poor performance,

    no being able o mee cusomer needs and/or demand requiremens.

    OSR Overseas RiskConsiders he possibiliy ha relaionships overseas are more difficul o manage, due o for

    example culural and poliical facors, bu also disance and language barriers.

    SUR Supplier RiskConcerned wih he chance ha he supplier goes ou of business / goes bankrup as a resul

    of poor managemen capabiliy.

    SSMSuppliers

    Supplier Risk

    Deals wih how he immediae (or Tier 1) supplier manages is sources of supply and he associaed risk,

    i.e. he buying companys second and possibly also hird and fourh ier suppliers.

    EIREngineering and

    Innovaion Risk

    Concerned wih he suppliers capabiliy o collaborae on design, he poenial for join

    innovaions, as well as he poenial for he leakage of confidenial informaion shared.

    TPR TransporaionRisk

    Measures he exen o which carriers can have problems in he physical movemen of goods.

    SVR Sovereign RiskAssesses he risk associaed wih giving up conrol when going overseas, including poenial

    poliical insabiliy, srikes, and sringen governmen regulaions

    NTRNaural Disasers/

    TerrorismLikelihood ha he supply chain can fall vicim o naural disasers and errorism atacks.

    Risk

    Factor

    Code

    Risk Factors Label Risk Factor Definitions

    TABLE :IDENTIFIED RISK FACTORS CONTINUED

    Insrumenal a his sage, peraining o he inegraion o FMEA wih heSCRMP, was ha as much deail as possible or each risk acor was colleced.

    The opporuniy o gaher his inormaion a his sage is given, since here

    is usually an underlying raionale or a eam member o sugges a paricular

    risk as being imporan. Specifically, or each idenified risk acor, we aimed o

    define he poenial ailure mode (i.e. how he specific risk maniess isel in

    erms o supply chain ailures or breakdowns or MLC), poenial causes o he

    ailure or breakdown, poenial effecs or consequences, possible prevenive

    acions, and he cos o such acion. These caegories were revised and/or

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    complemened wih addiional inormaion ha was riggered in he ensuing

    sages o he SCRMP. For example, or he on-ime and on-budge risk

    (risk acor code TBR; his risk acor will be used as an illusraive example

    hroughou), which addresses he abiliy o he supplier o deliver he produc

    wihou delays and wihou any higher coss, he poenial ailure mode or MLC

    was idenified as no having wha is needed and when i is needed. Poenial

    causes were atribued o he lack o manuacuring capabiliy and ransporaion

    flexibiliy on he par o he supplier. Effecs o his ailure were lower saey sock

    levels, los sales, and higher replacemen coss. Prevenive acions ha were

    idenified included a closer working relaionship wih logisics personnel and

    suppliers, he provision o help o he supplier or improving heir processes and

    capabiliies, and more effecive communicaion. The implemenaion o hese

    iniiaives was esimaed o cos $60,000. The FMEA analysis or all risk acors

    peraining o he China-Midwes supply chain is presened in Appendix A.

    Step 2: Assess the Severities of Consequences

    In he second sep o he SCRMP we uilized Miliary Sandard 882C (1993)

    o define he caegories o consequence severiies ino caasrophic, criical,

    marginal or negligible (yielding he Risk Consequence Index). The our-

    level sandard was adaped o MLC in a cross-uncional ashion involving

    he academics and he CEO o he company. As such, a caasrophic

    consequence (risk severiy index = 4) was described as he plan being shu

    down, equivalen also o no delivery occurring or more han one monh due

    o lack o componens and zero saey sock levels. The consequence wasdescribed as criical (risk severiy index = 3) i he process slowed down or i

    no delivery was received or more han one week due o lack o componens

    and zero saey sock levels. A siuaion wih decreasing service levels and

    depleing saey sock was described as marginal (risk severiy index = 2),

    while an insance wih service levels no being impaced due o sufficien

    saey sock levels was considered negligible (risk severiy index = 1). These

    degrees o magniude can be adaped based on he individual companys

    assessmen o wha would represen a caasrophic, criical, marginal or

    negligible even; according o he miliary sandard, he wors possible even

    is considered in each caegory. Wih hese definiions in place, we evaluaed

    each o he seveneen risk acors along heir respecive consequence severiyon he objecives o (a) cos reducion and (b) responsiveness (service levels).

    Since i was our inen o assess he curren offshoring sraegy