Evaluating the Suitability of an Enterprise Resource Planning System

Transcription

1 Evaluatng the Sutablty of an Enterpre Reource Plannng Sytem Francco Herrera, Enrque Herrera-Vedma Departamento de Cenca de la Computacón e I. A Ecuela Técnca Superor de Ingenería Informátca Unverdad de Granada Avda. de Andalucía 38, Granada, Epaña Teléfono: , Fax: , E-mal: herrera,vedma@deca.ugr.e Lu Martínez, Pedro J. Sánchez Departamento de Informátca Ecuela Poltécnca Superor de Jaén Unverdad de Jaén Avda. de Madrd, 35, Jaén, Epaña Teléfono: , Fax: , E-mal: martn,pedroj@ujaen.e

2 Evaluatng the Sutablty of an Enterpre Reource Plannng Sytem Summary The ue of Enterpre Reource Plannng (ERP) a a foundaton for the ntegraton of the complete range of bune procee and functon, clearly ueful and economcally proftable n mot very large organzaton whch deal wth great deal of data n ther nformaton ytem. However, the decon for ntallng an ERP ytem n all compane not alway o clear, t wll depend on the ze, future proft and other feature of the company. In th contrbuton, we hall preent an proce that t ueful for evaluatng the utablty of ntallng an ERP n a company. Th proce modelled a a Mult-Expert Decon Mang problem where we hall ue rather parameter ntead of alternatve. Th evaluaton problem defned over an heterogeneou context due to the fact that dfferent parameter evolved n the evaluaton of the utablty of the ytem are from dfferent nature and they wll be aeed n dfferent doman. Decon mang proce are uually compoed of two phae: () aggregaton and, () explotaton. In the current propoal the explotaton phae wll not order the parameter (alternatve), furthermore t wll obtan an overall value that we hall ue for evaluatng the utablty of ntallng the ERP ytem. Keyword: Lngutc varable, heterogeneou nformaton, decon proce, ERP 1. ITRODUCTIO The nformaton technologe (IT) have an enormou mpact on the productvty of the organzaton. Compane have mplemented ytem uch a Enterpre Reource Plannng (ERP), Materal Reource Plannng (MRP), Electronc Data Interchange (EDI), etc. n the lat year for mprovng ther productvty. However, ERP ytem have receved much attenton lately for ther potental n more effectve deconmang. The ntallaton of ERP ytem n bg compane ha produced an optmzaton of the compane nternal value chan and hence mportant advantage and proft. Th ucce ha nduced to other compane to ntall thee cotly ytem hopng mlar ucceful reult. However, the ntallaton of an ERP ytem very complex, expenve and ha a mave mpact on the entre organzaton. Due to thee reaon hould evaluate carefully the mplementaton of the ERP n order to avod unucceful reult n t mplementaton

3 orr (2000), Sheld (2001). The proce for evaluatng the utablty of ntallng an ERP ytem can be modelled by mean of a to Mult-Expert Decon Mang (ME-DM) problem. The man dfference that the evaluaton proce wll tudy dfferent parameter of the company ntead of alternatve. Thee parameter can have a dfferent nature and therefore, they need to be aeed by mean of heterogeneou aement. For example, the nformaton produced by nvetment or budget preent a quanttatve nature and are aeed by mean of numercal value Kacprzy (1986) or nterval-valued Le Téno (1998). However, other parameter a tandardzaton, rapd mplementaton, avalablty of peronnel, etc., preent a qualtatve nature and are aeed by mean of lngutc varable Zadeh (1975). A decon proce compoed of two phae Rouben (1997): () Aggregaton phae: that combne the ndvdual preference to obtan collectve preference () Explotaton phae: order the collectve preference to obtan a oluton et for the problem In the evaluaton proce the explotaton phae wll compute a meaurement on the utablty of mplementng an ERP n the organzaton. In th contrbuton we hall propoe a method to evaluate the utablty of the ntallaton of an ERP ytem n a company baed on a lngutc decon model. Th evaluaton problem defned over an heterogeneou nformaton context. In Herrera (2002) t wa defned a lngutc decon model ung the 2- tuple fuzzy lngutc repreentaton model Herrera (2000) for olvng decon mang problem defned over heterogeneou nformaton context. We hall ue th lngutc model to manage our problem n order to evaluate the utablty of the ntallaton of an ERP ytem. Th paper tructured a follow: n Secton 2 we hall mae a bref ntroducton to Enterpre Reource Plannng ytem; n Secton 3 we revew the 2-tuple lngutc repreentaton model that t wll be ued to manage the heterogeneou nformaton of our problem; n Secton 4 we preent the model for evaluatng the utablty of ntallng an ERP ytem n a company developng an example of th model. And fnally, ome concludng remar are ponted out. 2. ETERPRISE RESOURCE PLAIG An ERP ytem a tructured approach to optmzng a company' nternal value chan. The oftware, t fully ntalled acro an entre enterpre, connect the component of the enterpre through a logcal tranmon and harng of common data wth an ntegrated ERP. When data uch a a ale become avalable at one pont n the bune, t coure t way through the oftware, whch automatcally calculate

4 the effect of the tranacton on other area, uch a manufacturng, nventory, procurement, nvocng, and boong the actual ale to the fnancal ledger orr (2000), Sheld (2001). What ERP really doe organze, codfy, and tandardze an enterpre' bune proce and data. The oftware tranform tranactonal data nto ueful nformaton and collate the data o that t can be analyzed. In th way, all of the collected tranactonal data become nformaton that compane can ue to upport ther bune decon. When an ERP ytem fully developed n a bune organzaton, t can yeld many beneft: reduce cycle tme, enable fater nformaton tranacton, facltate better fnancal management, lay groundwor for e-commerce, and mae tact nowledge explct. ERP oftware not ntrncally trategc; rather, t an enablng technology, a et of ntegrated oftware module that mae up the core engne of nternal tranacton proceng. The ntallaton of an ERP, mple a great nvetment, becaue of, requre major change n the organzatonal, cultural and bune procee. The mot mportant change are thoe referred to ndvdual role nde the organzaton. A lot of ERP product have forced the compane, to redegn ther bune procee for removng uele ta and focung the releaed employee n value added actvte, ncreang dramatcally the company' productvty and hence t proft. Thee mprovement have produced that all world wde organzaton and ncreangly mall- and medumzed compane are ntereted n the ntallaton of th type of product. However, the utablty of the ERP not alway proftable. Becaue ERP ytem are very complex and have a mave mpact on the entre organzaton. Implementng an ERP ytem alway very expenve and tme conumng, furthermore the productvty and proft of the company can not ncreae dramatcally n ome cae. Therefore, before to ntall an ERP mut be evaluated t utablty n each company, analyzng a et of parameter Maetre (2002) of the organzaton to decde the vablty of the ERP mplementaton. In th paper we propoe a model baed on an heterogeneou lngutc decon proce that evaluate the utablty of an ERP accordng to dfferent parameter of each company. 3. THE 2-TUPLE LIGUISTIC REPRESETATIO MODEL Th model wa preented n Herrera (2000), for overcomng the drawbac of the lo of nformaton preented by the clacal lngutc computatonal model Herrera (2000b): () The emantc model, () and the ymbolc one. The 2-tuple fuzzy lngutc repreentaton model baed on the ymbolc method and tae a the bae of t repreentaton the concept of Symbolc Tranlaton.

5 Defnton 1. The Symbolc Tranlaton of a lngutc term S =,..., } a numercal value { 0 g aeed n [-0.5,0.5) that upport the dfference of nformaton between an amount of nformaton [0, g] and the cloet value n {0,,g} that ndcate the ndex of the cloet lngutc term n S ( ), beng [0,g] the nterval of granularty of S. From th concept a new lngutc repreentaton model developed, whch repreent the lngutc nformaton by mean of 2-tuple (, α ), S and α [ 0.5,0.5). Th model defne a et of functon between lngutc 2-tuple and numercal value. Defnton 2. Let S =,..., } be a lngutc term et and β [0, g] a value upportng the reult of a { 0 g ymbolc aggregaton operaton, then the 2-tuple that expree the equvalent nformaton to β obtaned β wth the followng functon: ( β) = (, α), wth [ 0, g] S ( 0.5,.0.5) : = round( β) α = β α [ 0.5,0,5) (1) where round( ) the uual round operaton, ha the cloet ndex label to β and α the value of the ymbolc tranlaton. Propoton 1. Let S =,..., } be a lngutc term et and, α ) be a lngutc 2-tuple. There alway a { 0 g ( 1 functon, uch that, from a 2-tuple t return t equvalent numercal value β [0, g] n the nterval of granularty of S. Proof. It trval, we conder the followng functon: 1 [ 0,5,0.5) [ 0 g] : S, 1 (, α ) = + α = β (2) Remar 1. From Defnton 1 and 2 and Propoton 1, t obvou that the converon of a lngutc term nto a lngutc 2-tuple cont of addng a value 0 a ymbolc tranlaton: S,0) (3) (

6 Th model ha a computatonal technque baed on the 2-tuple were preented n Herrera (2000): 1. Aggregaton of 2-tuple The aggregaton of lngutc 2-tuple cont of obtanng a value that ummarze a et of value, therefore, the reult of the aggregaton of a et of 2-tuple mut be a lngutc 2-tuple. In Herrera (2000) we can fnd everal 2-tuple aggregaton operator baed on clacal aggregaton operator. 2. Comparon of 2-tuple The comparon of nformaton repreented by 2-tuple carred out accordng to an ordnary lexcographc order. Let, α ) and, α ) be two 2-tuple repreented two aement: ( 1 ( l 2 If < l then, α ) maller than, α ) If =l then ( 1 ( l 2 1. If α 1 = α2 then (, α1 ) and ( l, α2 ) 2. If α 1 < α2 then (, α1 ) maller than ( l, α2 ) 3. If α 1 > α2 then (, α1 ) bgger than ( l, α2 ) repreent the ame value 4. EVALUATIG THE SUITABILITY OF A ERP SYSTEM An evaluatng proce of the utablty of an ERP ytem can be repreented a a problem that tude a et of parameter of the company X = x,..., x } that they are evaluated by n expert E = e,..., e } provdng { 1 m { 1 n ther evaluaton n dfferent doman, vector: D, accordng to the nature of the parameter by mean of utlty { 1,..., } m Let j ( {1,..., m}, j {1,..., n}, {, I, L} beng the evaluaton agned to the parameter x j by expert e aeed n the doman D. Each expert provde a vector wth h evaluaton. The doman ued n th problem to ae the evaluaton may be: umercal, Interval-valued and Lngutc. Accordng to the above cheme to evaluate the utablty of the ERP ytem, we propoe the ung of the lngutc decon proce preented n Herrera (2002) degned for dealng wth heterogeneou nformaton.

7 4.1. HETEROGEEOUS DECISIO PROCESS Here, we preent the aggregaton and explotaton phae of the lngutc decon proce for managng heterogeneou nformaton preented n Herrera (2002) that we hall ue to evaluate the utablty of an ERP Aggregaton phae In th phae the ndvdual evaluaton utlty vector provded by the expert are combned to obtan a collectve utlty vector. A the evaluaton of the expert are aeed n dfferent doman, numercal ( D ), I L nterval-valued ( D ) and lngutc ( D ). Th proce accomplhed a follow: 1. Mang the nformaton unform. The heterogeneou nformaton unfed nto a pecfc lngutc doman, called Bac Lngutc Term Set (BLTS) and ymbolzed a S T. The BLTS choen accordng to the condton hown n Herrera (2002). Afterward, each numercal, nterval-valued and lngutc evaluaton, a) Tranformng numercal value, j, tranformed nto a fuzzy et n j, n [0; 1], nto F( S T ): τ [ 01, ] F( S ) : T τ( j ) = {( 0, γ0),...,( g, γ g)}, ST, γ S T, F( S T ). [ 0,1 ] γ = µ ( j 0 ) = f j a b c 1 c j c d j Support( µ f f f a c d < < < j j j ( < b < d j < c )) (4) Remar: We conder memberhp functon, µ ( ), for lngutc label, ST repreented by a parametrc functon a, b, c, d ). (, are

8 b) Tranformng lngutc value, L j S, nto F( S T ): τ SST : S F ( ST ) τ SS T L ( ) = {( c, γ )/ {0,..., g}}, j L j S (5) γ = max y mn{ µ ( y), µ c j ( y)} where µ (y) and µ ( y) are the memberhp functon of the fuzzy et aocated wth the term j c L j and c, repectvely. When the BLTS a term et ued n the context the fuzzy et that repreent t lngutc term all 0 except the correpondent to the ordnal of the label that 1. I c) Tranformng nterval value, [ 01, ] j, nto F( T S ): Let I =, be an nterval value n _ [0,1]. We aume that the nterval-value ha a repreentaton, npred n the memberhp functon of the fuzzy et Kuchta (2000): The tranformaton functon : 0 f ϑ< µ I ( ϑ) = 1 f ϑ (6) 0 f < ϑ τ IST : I F( ST ) τ IS T L ( ) = {( c, γ ) / {0,..., g}} j (7) γ = max y mn{ µ I ( y), µ c j ( y)} where µ (y) the memberhp functon aocated wth the nterval-valued I j I j. 2. Aggregatng ndvdual utlty vector. For each parameter, a collectve value obtaned aggregatng the above fuzzy et on the BLTS that repreent the ndvdual evaluaton agned by the expert ung an aggregaton operator.

9 3. Tranformng nto 2-tuple: The collectve utlty vector expreed by mean of fuzzy et n the BLTS are tranformed nto lngutc 2-tuple n the BLTS. Th tranformaton carred out ung the functon χ and the functon (Def. 2): [ 0 g] χ: F ( S T ), j γ j j= 0 χ ( τ( ϑ)) = χ({( j, γ j ), j = 0,..., g} = = β g γ g j= 0 j (8) Explotaton phae Over the collectve preference vector the explotaton phae, uually, obtan the bet alternatve(). However, n th problem t compute an overall value expreed by mean of a lngutc 2-tuple. Th overall value expree a meaurement of the degree of utablty for the ntallaton of the ERP oftware n the company. In our propoal we compute th overall meaurement aggregatng the collectve value for each parameter. Th degree of utablty wll be evaluated n a predefned table, uch that, dependng on t value t pont out the utablty or unutablty of ntallng the ERP ytem EVALUATIG THE ISTALLATIO OF A ERP The evaluaton of the degree of utablty for the ntallaton of an ERP tae nto account a conderable amount of company' parameter. In th ecton, we preent an example of the evaluatng proce. We tae nto account the followng parameter of the company, aeed n dfferent doman, for evaluatng the utablty of the ERP ytem: X 1 Invetment n IT for employee an nterval-valued wth a maxmum value of 6000 X 2 Prce of the mplementaton a numercal value wth a maxmum value of ; X 3 Urgency n the mplementaton are aeed by lngutc value n the lngutc term et A X 4 Standard degree are aeed by lngutc value n the lngutc term et C X 5 Interrelaton wth other ubytem a numercal value aeed n [0,1] X 6 Capacty of the uer to pecfy are aeed by lngutc value n the lngutc term et C X 7 Requet of change by the uer aeed by lngutc value n the lngutc term et B X 8 Avalablty of peronnel are aeed by lngutc value n the lngutc term et B

10 X 9 Capacty of nfluence of the clent n the provder are aeed by lngutc value n the lngutc term et D The emantc of the term et are howed n the Table 1 and graphcally n Fgure 1. Table 1: Label term et Term Set A Term Set B Term Set C Term Set D A 0 (0,0,12) B 0 (0,0,.16) C 0 (0,0,.25) D 0 (0,0,0,0) A 1 (0,.12,.25) B 1 (0,.16,.33) C 1 (0,.25,.5) D 1 (0,.01,.02,.07) A 2 (.12,.25,.37) B 2 (.16,.33,.5) C 2 (.25,.5,.75) D 2 (.04,.1,.18,.23) A 3 (.25,.37,.5) B 3 (.33,.5,.66) C 3 (.5,.75,1) D 3 (.17,.22,.36,.42) A 4 (.37,.5,.62) B 4 (.5,.66,.83) C 4 (.75,1,1) D 4 (.32,.41,.58,.65) A 5 (.5,.62,.75) B 5 (.66,.83,1) D 5 (.58,.63,.80,.86) A 6 (.62,.75,.87) B 6 (.83,1,1) D 6 (.72,.78,.92,.97) A 7 (.75,.87,1) D 7 (.93,.98,.99,1) A 8 (.87,1,1) D 8 (1,1,1,1) Fgure 1: Label term et

11 In th example, four expert evaluate the utablty of the ERP provdng ther aement over the parameter by mean of utlty vector (ee Table 2): Table 2: Expert aement E 1 E 2 E 3 E 4 X 1 [3500,4000] [2000,2500] [3100,3800] [4500,5000] X X 3 A 5 A 6 A 5 A 4 X 4 C 2 C 2 C 3 C 1 X X 6 C 1 C 1 C 2 C 3 X 7 B 3 B 4 B 3 B 4 X 8 B 4 B 5 B 5 B 3 X 9 D 7 D 6 D 5 D 5 The parameter X 2, X 5, X 6, X 7, X 8 have not an ncreang nterpretaton,.e., hgh value ndcate a mnor degree of acceptance. Then, thee parameter are nverely tranformed before to mae unform the nformaton. On th way, all parameter have an ncreang nterpretaton. Table 3: Increang Interpretaton E 1 E 2 E 3 E 4 X 1 [.58,.67] [.33,.42] [.52,.63] [.75,.83] X X 3 A 5 A 6 A 5 A 4 X 4 C 2 C 2 C 3 C 1 X X 6 C 3 C 3 C 2 C 1 X 7 B 3 B 2 B 3 B 2 X 8 B 2 B 1 B 1 B 3 X 9 D 7 D 6 D 5 D 5

12 ow we apply the decon proce: 1. Aggregaton phae (a) Mang the nformaton unform 1. Chooe the BLTS. In th cae, there are two term et wth the maxmum granularty and dfferent emantc, hence, we chooe a S T the pecal term et of 15 label gven n Fg. 2 accordng to Herrera (2002). Fgure 2: A BLTS wth 15 term ymetrcally dtrbuted 2. Tranformng the nput nformaton nto F(S T ) (ee Table 4). Table 4: Input nformaton nto F(S T ) E 1 E 2 E 3 E 4 X 1 (0,0,0,0,0,0,0,.86,1,.43,0,0,0,0,0) (0,0,0,0,.43,1,.86,0,0,0,0,0,0,0,0) (0,0,0,0,0,0,0,.71,1,.86,0,0,0,0,0) (0,0,0,0,0,0,0,0,0,0,.43,1,.71,0,0) X 2 (0,0,0,0,0,0,0,1,0,0,0,0,0,0,0) (0,0,0,.57,.43,0,0,0,0,0,0,0,0,0,0) (0,0,0,0,0,0,0,0,.86,.14,0,0,0,0,0) (0,0,0,0,.43,.57,0,0,0,0,0,0,0,0,0) X 3 (0,0,0,0,0,0,0,.36,.73,.89,.55,.2,0,0,0) (0,0,0,0,0,0,0,0,.1,.45,.79,.84,.47,.09,0) (0,0,0,0,0,0,0,.36,.73,.89,.55,.2,0,0,0) (0,0,0,0,0,.29,.65,1,.63,.26,0,0,0,0,0) X 4 (0,0,0,.12,.34,.56,.78,1,.78,.56,.34,.12,0,0,0) (0,0,0,.12,.34,.56,.78,1,.78,.56,.34,.12,0,0,0) (0,0,0,0,0,0,0,.21,.43,.65,.87,.9,.68,.45,.21) (.21,.65,.68,.9,.87,.65,.43,.21,0,0,0,0,0,0,0) X 5 (0,0,0,0,0,0,0,0,0,0,0,.71,.29,0,0) (0,0,0,0,0,0,0,0,0,.86,.14,0,0,0,0) (0,0,0,0,.57,.43,0,0,0,0,0,0,0,0,0) (0,0,0,0,0,0,0,0,0,.14,.86,0,0,0,0) X 6 (0,0,0,0,0,0,0,.21,.43,.65,.87,.9,.68,.45,.21) (0,0,0,0,0,0,0,.21,.43,.65,.87,.9,.68,.45,.21) (0,0,0,.12,.34,.56,.78,1,.78,.56,.34,.12,0,0,0) (.21,.65,.68,.9,.87,.65,.43,.21,0,0,0,0,0,0,0) X 7 (0,0,0,0,.12,.41,.7,1,.69,.39,.08,0,0,0,0) (0,0,.24,.54,.83,.87,.58,.29,0,0,0,0,0,0,0) (0,0,0,0,.12,.41,.7,1,.69,.39,.08,0,0,0,0) (0,0,.24,.54,.83,.87,.58,.29,0,0,0,0,0,0,0) X 8 (0,0,.24,.54,.83,.87,.58,.29,0,0,0,0,0,0,0) (.3,.97,.95,.75,.45,.16,0,0,0,0,0,0,0,0,0) (.3,.97,.95,.75,.45,.16,0,0,0,0,0,0,0,0,0) (0,0,0,0,.12,.41,.7,1,.69,.39,.08,0,0,0,0) X 9 (0,0,0,0,0,0,0,0,0,0,0,0,0,.58,.87) (0,0,0,0,0,0,0,0,0,0,.35,.76,1,.92,.33) (0,0,0,0,0,0,0,0,.5,1,1,1,.61,.07,0) (0,0,0,0,0,0,0,0,.5,1,1,1,.61,.07,0)

13 3. Aggregatng ndvdual performance value. In th example we ue a aggregaton operator the arthmetc mean obtanng the collectve value howed n Table 5. Table 5: Aggregated data X 1 (0,0,0,0,.11,.25,.22,.39,.5,.32,.11,.25,.18,0,0) X 2 (0,0,0,.14,.22,.14,0,.25,.22,.04,0,0,0,0,0) X 3 (0,0,0,0,0,.07,.16,.43,.55,.62,.47,.31,.12,.02,0) X 4 (.05,.16,.17,.29,.39,.44,.5,.61,.5,.44,.39,.29,.17,.11,.05) X 5 (0,0,0,0,.14,.11,0,0,0,.25,.25,.18,.07,0,0) X 6 (.05,.16,.17,.26,.3,.3,.3,.41,.41,.47,.52,.48,.34,.23,.11) X 7 (0,0,.12,.33,.59,.72,.68,.65,.39,.28,.17,.06,0,0,0) X 8 (.15,.49,.54,.51,.46,.40,.32,.32,.17,.10,.02,0,0,0,0) X 9 (0,0,0,0,0,0,0,0,.25,.5,.59,.69,.56,.41,.30) E (b) Tranformng the collectve value nto 2-tuple n S T. The reult of th tranformaton : Table 6: Aggregated data n 2-tuple X 1 X 2 X 3 X 4 X 5 X 6 X 7 X 8 X 9 E (S 8,0) (S 6,-.19) (S 9,-.23) (S 7,-.07) (S 9,-.32) (S 8,-.18) (S 6,-.03) (S 4,-.1) (S 11,-.02)

14 2. Explotaton phae. In th phae we obtan an overall utablty value for the ntallaton of the ERP that wll be evaluated accordng to the followng recommendaton table: Table 7: Table of utablty Degree of utablty Recommendaton < S 4 ot ntall > S 4 and < S 6 The ntallaton not utable > S 6 and < S 9 The ntallaton feable > S 9 and < S 11 The ntallaton utable > S 11 The ntallaton very utable We ue the 2-tuple arthmetc mean operator Herrera (2000) to obtan the degree of utablty for the ntallaton of the ERP: (S 7,-.07) Therefore n th example the ntallaton of the ERP feable but not utable. 5. COCLUDIG REMARKS In th contrbuton, we have propoed the applcaton of a lngutc decon proce for evaluatng the utablty of ntallng an ERP ytem n a company. The proce evaluate the parameter, of the current condton of the company, accordng to the opnon of the expert. Thee parameter are aeed n dfferent nformaton doman. The method propoed combne the heterogeneou nformaton provdng by the expert, n ther evaluaton of the parameter, for obtanng an overall meaurement of the utablty for the ntallaton of the ERP. Th proce more flexble than other one that force to the expert to provde ther opnon n an unque expreon doman Maetre (2002). Acnowledgement Th wor partally upported by the Reearch Project TIC and TIC and FEDER Fund

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