The development of a decision support system for energy cost management, using an expert system shell : a case study in the integrated use of software packages : report presented in fulfilment of the thesis requirements for the degree of Master of Technol

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(1)Copyright is owned by the Author of the thesis. Permission is given for a copy to be downloaded by an individual for the purpose of research and private study only. The thesis may not be reproduced elsewhere without the permission of the Author..

(2) THE D EVELOPMENT O F A DECIS ION SUP PORT S Y S TE M F O R ENERGY CO S T MANAGEMENT , U S ING AN EXPERT S Y S TE M S HE L L . A CASE STUDY IN THE INTEGRATE D USE OF SOFTWARE PACKAGE S. Rep o rt p re s e nted b y L J ROBERT S ON In fu l filme nt o f the the s i s requ i reme nts f o r the degre e o f ; Mas te r o f T echno logy. MAii�ifllHflli illl li llffliif 1061960754. y. ( C omputing T e chno l ogy ) .. 1989.

(3) 1. THE DEVE LOPMENT OF A D EC I S I ON SUP PORT S Y S TEM FOR ENERGY C O S T MANAGEMENT , U S ING AN EXPERT S Y S TEM S HE L L . A CASE STUDY I N THE INTEGRATED USE OF SOF TWARE PACKAGE S. Repo rt p re s e nted by L J ROBERT S ON I n fu l fi lme nt o f the the s i s r e qu i reme nts f o r the degree o f ; Ma s ter o f T e chnology. (C omputi ng T e chno l o gy ) .. 1989.

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(5) 2. TABLE OF CONTENT S. 1. AB S TRACT. 2. INTRODUCT I ON. 3. S TANDARD PC S OF TWARE PACKAGES AS TOOLS FOR " REAL " P ROBLEMS . U s e r spe c i f i c at i o n s fo r u s e fu l app l i cat i on s . Compu t e r funct i on s ; bu i l d i n g b l o c k s f o r us e fu l app l i c at i o n s . S o ftware t o o l p a c k age s ; s e t s o f computer funct i on s . App l i cat i on s requ i r i ng i n t e g r a t e d u s e o f more t han one s o ft wa r e t o o l pa ckage ; s e l e ct i o n o f packages a n d s t r at e gy .. 4. ENERGY CO ST MANAGEMENT ; AN AP P L I CAT I ON FOR I NTEGRAT I ON OF S TANDARD S OFTWARE TOOL FUNCT I ONS I nt roduct i o n t o Ene rgy Co s t Management ( E CM) . E CM us ing an L o t u s Symphony . Ene rgy Co s t Man agement us ing mu l t ip l e s o ftware p a ckage s .. 5. DATABAS E MANAGEMENT S UP P ORT FOR ECM . D BMS suppo rt requ i rement s . D at a ent ry modu l e . " I nt e l l i gent dat ab a s e " fun ct i on s .. 6 DECI S I ON SUP P ORT SYS TEM DEVE LOPMENT . D e f i n i t i o n o f ove r a l l a ims . D eve l opment methods . H i gh leve l E CM de c i s i o n t o o l . MD cont r o l b y l o a d p a t t e rn a d j u s t ment . MD cont r o l b y operat i on re s chedu l in g . P r ot otyp e deve l opment p robl em s and � o l ut i o n s . T e s t ing and eva luat i o n o f f i n a l ve rs i on . 7. CONCLU S I ONS . T h e value o f integrated u s e o f P C S o ft w a r e p ackages . Eva l u at i on o f the de c i s ion supp o rt and dat ab a s e s upport s y s t ems f o r ECM .. 8. REFERENCE S AND ACKNOWLEDGEMENT S .. APPEND I X AP PEND I X APPEND I X AP PEND I X AP PEND I X AP PEND I X AP PEND IX AP PEND I X AP PEND I X AP PEND I X. A B C D E F G H I J. CURRENT ECM S P READ SHE E T OUTP UTS DATA U S E D IN D EC I S I ON S U P P ORT S Y S TEM DEC I S I ON SUP P ORT S Y S TEM O P E RAT I ON KNOWLEDGE BASE RULE S & S OURCE CODE VP EXP ERT T I P S , TRICKS AND T RAP S DATA D I CT I ONARY ( P ROP OSED D BMS ) DATA ENTRY MODULE S OURCE CODE S P E C I F I CAT I ON FOR FURTHER WORK RES ULTS O F KNOWLEDGE ACQU I S I T I ON EXERC I S E ; SUPERSEDED KNOWLEDGE BASE S.

(6) 3 1. ABSTRACT. 1.1. Key p hr a s e s : Ene rgy c o s t management; E xp e r t s y s tem; De c i s ion suppo rt s y s tem; Inte g r a ted use of s o ftwa re p roducts .. 1.2. Abs tr act. The the o ry o f m i n imi z i ng tota l ene rgy us age i s we l l known ( i f not we l l documented ) , and the te chn i qu e s a r e wide l y p r acti ce d . Becau s e o f the w a y in whi ch ene rgy i s s o l d , the total co s t incurred may be a f f e cted even more s trongly by the time -di s tr ibution o f the ene rgy u s age , than by the tota l quanti ty u s e d . A m a j o r sub j e ct o f ECM i s the MANAGEMENT o f th i s time di s tributi on o f energy us age , w i th the ob j ective o f m i n imi z in g o f total ene rgy c o s ts to the u s e r . A s o f tware pack age ( n amed ECME S , Energy C o s t Man agemen t E xpert S y s tem) h a s b e e n deve l oped us i n g the L o tus S ymphony integrated spre adsheet s o ftware p a c k age . The ECME S app l i cati o n cons i s ts ( cu r rentl y ) o f thr e e modu l e s o f fe r i ng ana l y s e s o f s eve r a l a spe cts o f e l e ctr i c a l ene rgy c o s t management ( p lu s three c o r responding modu l e s for gas c o s ts , which are n o t The Symphony E CM app l i cati on con s i de r e d further ) . modu l e s have been deve l oped ove r the l a s t few y e ar s , l arge l y on a spare time ba s i s , b y P r o f e s s o r W Mon te i th o f Ma s s e y Un i ve r s i ty's P roduction T e chno l ogy D ep artment . The a n a l y s i s o f Ene rgy C o s t Management on a P C i s one which r e qu i re s functions s upp l i ed b y seve r a l s tandard s o ftware package s , p a rti c u l a r l y spreadshe e t , graphics , datab a s e and e xpert s y s tem . T h e r e l ative l y r ecent ava i l ab i l i ty o f mode rate l y p r i ced and u s e r f r i endly e xp e r t s y s tem deve l opment packages has b rought a n additi o n a l s e t of p owe r fu l to o l s w i th i n the r e ach o f the app l i c ati on deve l op e r . A D e c i s i on S upport S y s tem ( u s i ng an E x p e rt S y s tem she l l ) h a s b e e n deve loped, whi ch i s we l l integrate d with the s p readsheet data , and with a datab a s e , to e xp and the functi ons of the o r i ginal s p r e adsheet ECM ana l y s i s to o l . The o re ti c a l work o n the data r e qui rements and the p r o ducti o n ru l e s has opened up p o s s i b i l i ti e s for futu r e work ..

(7) 4 2. INTRODUCT I ON The the o r y o f min imi z ing t ot a l e n e rgy us age i s we l l known ( i f not we l l do cument e d ) , and t he t e chn i que s B e c ause o f the way i n whi ch are wi de l y p r a ct i ced . ene rgy i s s o l d , the t ot a l c o s t i n curr e d may b e a f fe ct e d even more st r o n g l y by t he t ime -di s t r ibut i on o f the A ma j o r ene rgy usage , than by the t ot a l quant i t y u s e d . sub j e ct o f ECM i s the MANAGEMENT o f t h i s t ime d i s t r ibut i on o f ene rgy us age , w i t h t he ob j e ct ive o f mi n imi z ing o f t o t a l ene rgy cost s t o t he u s e r . A s o ftware p ackage ( n amed ECME S , Ene rgy C o s t Man agement E xp e rt S y s t em ) h a s b e e n deve l op e d us ing the Lotus S ymphony integrat e d s preads heet p ro duct . The ECME S app l i cat i on cons i s t s ( current l y ) o f t h r e e modul e s o f fe r i n g ana l y s e s o f s eve r a l aspe ct s o f e l e ct r i cal energy c o s t management ( p lu s three c o r r e sponding modu l e s fo r g a s c o st s , wh i c h are not c o n s i de r e d furthe r ) . The Symphony E C M app l i cat i on modul e s have been deve l oped over the l a s t few ye a r s , l arge l y on a spare t ime ba s i s , by P ro fe s s o r W Mont e i th o f Ma s s e y Un i ve r s it y ' s P r oduct i o n T e chno l ogy Department . It i s a s o ftwa r e package who s e " t ime has c ome " , appe a r i ng in a t ime when ene rgy c o s t management i s b e c oming r e c o gn i s e d as o f great comme r c i a l s i gn i fi cance , a n d i t s s t udy i s The Lotus S ymphony deve l op ing into a recogn i s e d f i e l d . s o ftware package used to develop the ECME S p a c k age o f fe r s a very powe r ful t o o l for dat a ana l y s i s o f thi s typ e , combin ing " t radit i ona l " spre adshe et , f i l e management , and word p r o c e s s ing fun c t i on s a s we l l a s a powe r ful macro " l anguage " , and g o o d s creen handl ing fac i l it i e s . ·. The Symphony b a s e d ECM app l i cat i on w a s conce ived from the beginn ing as one whi ch would carry o ut many o f the funct i ons unde rt aken b y an e xp e r t , and hence could be c l a s s e d ( i n the mo st gen e r a l s en s e of the phra s e ) as an " expe rt s y s t em " . Dur i ng 1 9 8 8 , howeve r , i t was recogn i s e d that there we re opportun it i e s f o r e x t ending the u s e fulne s s o f the package by int e grat ing the . sp readshe et package with a " convent i onal " e xpe rt s y s t em app l i c at i on . Although the faci l i t i e s o ffered b y S ymphony are suf f i c i ent ly powe r ful t o a l l ow an e x p e rt s y s t em to be const ruct e d , thi s was r e c ogn i s e d to b e an i ne f fi c ient appr o a ch t o p rovi di ng the s e funct i o n s . The i nve s t igat ion o f the s o ftware r e qu i rement s , the spe c i f i c at i on and deve l opment of t h i s expert s y s t em app l i c at i o n , and t he met h o d o f int eg r at i on o f t he package s f o rm the sub j ect s o f t h i s t h e s i s . As i s evident from the t it l e , the the s i s h a s two aspe ct s ; the gene r a l a s p e ct o f int e g r at ing the funct i on s o f s eve r a l ( s t andard) P C s o ftwa r e t o o l s , and the mo r e spec i fi c a sp e ct o f p r oviding a de c i s i on support app l i cat i o n f o r the ( L otus S ymphony b a s e d ) Energy C o s t Management package ..

(8) 5 The t he s i s i s s t ructured s o a s t o p r e s ent t he more gene r a l a sp e ct s of s o ftware int egrat i o n f i r s t , p r o c eed to an e xaminat ion o f Ene rgy C o s t Management ( b o t h as a s ub j e ct , and then a s a f ac i l it y provi ded b y the s p r e adshe e t package ) , and fina l l y to t h e deve l opment and i n t e g r at i on of de c i s i o n s upport s y s t em . The de c i s i on s upport s y stem deve l op e d i s w e l l i n t e g r a t e d w ith both the S ymphony-b a s e d Ene rgy C o s t Management appl i cat i o n , and a l s o with a dat ab a s e f a c i l i t y . Funct i ons a r e p rovided wh ich e xt e nd u s e r unde r s t anding o f the ene r gy u s age withi n the i r o rgan i s at i on , and a l l ow det a i l ed and h i gh l y i nt e r act ive e xp l o rat i o n o f the e f fect s o f changing e n e rgy u s e patt e rn s o n t ot a l e n e r gy c o s t s . In the c o u r s e o f the p r o j ect , e xp e r i ence has been ga i ned in the f i e l d o f ene rgy c o s t management genera l l y , the t h e o r y and u s e o f e xp e rt s y s t em she l l s , and the theory and p r a ct i ce o f i n t e g r at e d u s e o f s o ftware package s . The D e c i s i on Suppo rt S y s t em deve l op e d i s b y n o me an s a f i n i s hed p r o duct , and speci f i c at i on s a r e s u gge s t e d f o r future wo rk ..

(9) 6 3. STANDARD P C S OF TWARE PACKAGE S AS TOOLS PROBLEMS .. FOR " REAL ". CHAP T E R SUMMARY T h i s s e ct i o n s e t s out t o exp l o re b r i e f l y t h e qua l i t i e s a n d spe c i ficat i o n s whi ch wi l l a l l ow a comput e r app l i cat i on t o be o f u s e t o a u s e r , t he ( p r im i t ive ) s o ftwar e funct i on s requ i red f o r s u ch app l i c at i on s , and t he d i s t r ibut i o n o f t he s e funct i o n s among t he s t andard s o ftware t o o l p a ckage s . T h e f i n a l part o f t h i s s e ct i o n exp l o re s t h e i s sue s invo l v e d i n deve l op in g app l i cat i on s requ i r ing t he funct i on s o f m o r e than o n e s o ftware t oo l . CHAP TER CONTENTS STANDARD P C S OF TWARE PACKAGE S AS TOOLS FOR " REAL " PROBLEMS . 3.1 U S E R SPEC I F I CAT IONS FOR USEFUL APP L I CAT I ON S 3.1.1 Accept the dat a ava i l ab l e . P e r f o rm t he t a s k ( s ) requ i r ed . 3.1.2 3.1.3 P e r fo rm t a s k s i n t h e way requ i re d . 3.1.4 P r e s ent the r e s u l t s i n the way requ i r e d . 3.2 C OMP U TER FUNCT I ONS ; BU I LD ING B LOCKS FOR U S E FUL AP P L I CAT I ON S 3.2.1 Funct i on s requ i re d . 3.2.1.1 D a t a input and ve r i f i cat i on . D a t a s t o r age and ret r i eva l . 3 .2 . 1 .2 3.2 . 1 .3 Mathemat i c a l manipu l at i o n / p r o c e s s ing . 3.2 . 1 .4 P ro g r am f l ow contro l . 3.2 . 1 .5 P re s e ntat i o n o f r e s u lt s . 3.3 SOFTWARE TOOL PACKAGE S ; S E T S OF COMP UTER FUNC T I ON S 3.3.1 Gene r a l purpo s e p r o gramming l angu a ge s . 3.3.2 D at ab a s e management s y s t ems ( DBMS ) . E xpe rt S y s t em . 3.3.3 3.3.4 Spreadsheet . Word P ro ce s s ing . 3.3.5 3.4 APP L I CAT I ON S REQUIRING I NTEGRATED USE OF MORE THAN ONE S OF TWARE TOOL PACKAGE ; SELECT I ON OF PACKAGES . AND S T RATEGY . 3.4.1 P r ospect s f o r i n t e g r at i on . S p r eadsheet / D at abas e . 3.4.1.1 3.4.1.2 Spreadsheet w i t h Exp e rt S y s t e m . E xp e rt S y s t e m ( appl i ca t i on ) w i t h 3.4.1.3 D a t ab a s e . Word p roce s s i n g with Spreadshee t , and 3.4.1.4 dat ab a s e . 3.4.2 Methods o f app r o a c h i ng int egrat i on . 3.4.2.1 S e l e ct and u s e an int egrat e d s o ft w a r e p r o duct . P ro g r amming l an guage s ( 3GL ' s ) . 3.4.2.2 U s e individu a l s t andard s o ftware 3.4.2.3 package s . 3.4.3 I ntegrat i o n o f ope r a t i on . 3.4.3.1 "Aut omenu " ( o r e qu i v a l ent ) . 3.

(10) 7 Use o f Mi cro s o ft " Windows " , " De s qv i ew " , o r " S o ft �are C a r ous e l " . Use o f one o f t he app l i c at i on package s 3.4.3.3 t o cont r o l u s e o f o t he r s . 3.4.3.4 Use o f a mu lt i t a s k ing Ope rat i ng s y s t em . Int egrat i on o f dat a . 3.4.4 3.4.5 Eval uat i on and s e l ect i on o f p a ckage s and appr o ach met ho d . 3.4.5.1 I nt e g r at i on app r o a ch . Eva l u at i o n o f p a ckages . 3.4.5.2 As s i gnment o f funct i ons . 3.4.5.3 3.4.3.2. 3.1. USER SPEC I F I CAT I ON S FOR USEFUL APP L I CAT I ONS. 3.1.1. Accept t he data ava i l ab l e . The app l i cat i on should not demand dat a unt i l i t i s act u a l ly requ i red . I t should cont a i n on l y an app ro p riat e l evel o f dat a va l i dat i o n , and should p r o v i de amp l e opp o rtun i t y for reent ry . G o o d f a c i l it i e s f o r r eview o f data s h o u l d be ava i l ab l e . 3.1.2. P e r f o rm the t a s k ( s ) r e qu i red . The app l i cat i on deve l oper n e e d s t o g i ve much att e n t i on t o the de f i n i t i on o f the r e a l TAS K ( in human t e rm s , as opp o s ed to c omputer t e rms ) to be undert aken , mak i n g the ve ry care ful d i st inct i o n between t ho s e requ i r e d b y the ope rat o r , and tho s e requ i re d b y t he app l i c at i on . Not e ; from a m a rk e t i n g p e r sp e ct ive , i t i s e s s ent i a l t h e a u s e r b e ab l e t o readi l y app r e c i a t e So ftware t h e t a s k whi ch t h e package o ff e r s . funct i on s / c ap ab i l it i e s mu st then be s e l e 2t ed and i nt e g r ated to o f fe r t he great e st f a c i l i t y to the P ERS ON unde r t aking the t a s k . Ve ry few r e a l t a s ks can be comp l e t e ly accomp l i shed by a c omput e r - P E OPLE need t o s t a r t and fin i sh the m , t h e comput e r i s a lmo st a lway s a j u s t a t o o l . As with any t oo l , i t i s qu i t e p o s s ib l e f o r p o o r s o ftwar e t o make t h e accomp l i shment o f a t a s k mo r e o n e r o u s , o r s l owe r , r athe r than e a s i e r a n d qu i cke r . 3.1.3. P e rfo rm t a s k s i n the way r e qu i red . Ope rat i o n s not d i r e ct ly and n e c e s s a r i l y p art o f the u s e r' r e a l TAS K f o rm a di s t r act i on , _and n e e d t o b e e l im i n ated i f p o s s ib l e . Mo re c ommo n forms o f d i s t r ac t i o n i n c l ude t he n e e d t o r�fe r t o a l a rge s o ftwa r e manual ( appl i ca t i ons s ho u l d be s e l f documen t ing ) , u n c l e a r c ommands and menu cho i c e s , and l ack o f flexib i l it y ava i l ab l e in s e quencing o f act i v it ie s .. 3.1.4. P re sent the r e s u l t s i n the way requ i r e d . I t i s undoub t e d l y e a s i e r t o a s s im i l a t e s u ch i n f o rm at i on as t rends and p att e rn s f r om graphi c a l l y pre s e n t ed dat a than from t e xt ; un f o r t unat e l y , t he faci l i t ie s f o r inputt i n g g r aph i c a l i n format i on are n e i t he r as cheap , n o r r e a d i ly ava i l ab l e a s the me a n s.

(11) 8 for p r e s ent i ng gr aphi c a l dat a . Text p r e s en t at i o n i s s t i l l n e c e s s ary f o r c a s e s whe r e individu a l dat a i t ems need t o be input / output . Apart from t he i s su e o f graphi c s ve rsus t ext , t he e a s e with whi c h a u s e r c an a s s im i l at e t he dat a p r e s ented depends he av i l y o n t he quant i t y o f dat a whi ch i s p r e s ent ed at any o n e t ime , and how i t i s pre s e n t e d ( a s we l l as how attent i on focus s ing device s s u c h a s c o l o u r , b l i n k i n g t e xt e t c a re u s ed) . G o o d s creen l ayout i s e s sent i a l ..

(12) 9. 3.2 C OMPUTER FUNCT I ONS ; BU ILD ING BLOCKS FOR U SE FUL APP L I CAT I ONS 3.2.1. F unct i o n s requ i red. 3 . 2 . 1 . 1 D at a i nput and ve r i f i cat i on Not e ; T he mo st gen e r a l interpretat i on o f " da t a input (met ho d ) " is intended (i e , the i n c lu s i on o f i nput obt a in e d from keyboard, mous e , commun i c at i on s p ackage , remo t e data acqu i s it i on devi ce s , e t c ) , a s i s t he mo st gene r al inte rpretat i on o f " dat a " (i e keyb o a r d cha r a c t e r s a s we l l ik on a n d menu i t em s e l e ct i on s ) . D at a input funct i o n s requ i re d by t ru e s o ftware app l i c a t i o n s vary great l y , but s eve ral c l a s s i f i c at i o n s a r e i mp o r t an t ; T he i mportance o f correctn e s s : B anking o r medi cal data a t o n e ext reme , and " sp e cu l at ive " dat a such a s i s common l y u s e d i n s p re adshe e t app l i c at i ons , a t t he o t he r e xt reme . The v o lume o f dat a: D at ab a s e app l i c at i on s , in contrast to expe rt s y stem app l i cat i on s . T he d o main and presentat i on o f dat a : E xpert s y s t em input frequent l y requ i re o n l y s e l ect i on f r om among a l imit e d numb e r o f (menu ) c ho i c e s whe reas t he i nput o f l a rge qu ant i t i e s o f r e a l numb e r s o r text may b e n e c e s s a r y fo r a d a t ab a s e app l i cat i o n . T he m o de o f data ent ry B a t c h or inte ract ive . T he degree t o whi ch t he s o ftwar e c o n s t r a i n s and s t ru ct u r e s t he s e quence and fo rmat o f dat a e n t r y ; S p readshe et s and wo rd p r o c e s s ing p a ckage s i mp o s e v e ry l oo s e requi rement s o n t h e sequ en c e e t c o f d a t a ent r y ; dat ab a s e s y s t ems genera l l y r e qu i r e t he m o st s evere con s t r a i nt s on the format o f dat a e nt r y , whi l e Expert s y st ems t end t o i mp o s e r e st r i ct i on s part i cu l ar l y o n the s e quenc i ng o f d at a ent ry event s . 3 . 2 . 1 . 2 D at a s t o rage and ret r i eval A l l but the mo st s imp l e app l i c at i o n s requ i r e t o s t o r e and ret r i eve dat a ; the que s t i o n s t o b e a n swered r e l at e t o t he quant it y , t he requ i r e d speed o f ret r i e va l , and t he fo rmat t ing o f t h e dat a . 3 . 2 . 1 . 3 M a t hemat i c a l man ipu l at i on / p r o c e s s ing Mathemat i c a l manipu l at i on , i n t h i s cont e xt r e fe r s t o any (bat ch ) ope rat i on whi ch t ak e s nume r i c al dat a a s i t s i nput , and produce s nume r i c a l output without any furt he r int e rvent i on by t he ope r at o r . Thi s de f i n i t i on t he r e f o re i n c lude s such ope r at i on s a s fou r i e r a n a l y s i s , mat r i x oper at i on s , s o lut i on o f di f f e r ent i a l e qu at i o n s , findin g o f r o ot s , curve f i t t ing e t c , as we l l a s t he more s imp l e " ca l c u l at o r " funct i o n s ..

(13) 10 3 . 2 . 1 . 4 P ro g r am flow cont rol (de c i s i on mak i n g , men u s e l e ct i on et c ) The modern t e ndency i s t o a l l ow p r o g r am f l ow t o be cont r o l l e d b y the use of pul l -down menu s , mou s e and icons s y s t e m s et c . G o od gu i de l ines for the s e l e ct i on and de s i gn o f menu i t ems etc e x i s t : Each menu s h o u l d have ( i n t he s ame p o s i t i on ) t h e me ans f o r retur n i n g t o the p r evi o u s menu and t o the ma i n menu , t h e menu cho ice s s h o u l d be unambiguous , and the de fault i t e m (o r the i n it i a l cur s o r p o s i t i o n ) should be cho s e n w i t h care . 3 . 2 . 1 . 5 P re s en t a t i o n o f r e su l t s Ke y a spects a r e the use o f s ome t e chn i qu e t o f o c u s att ent i on on the c r i t i ca l i t e m s (e ither by the u s e o f co l our , " wi n dows " o r c a re ful s c reen de s i gn ) , and s imu lt ane ou s l y pres e nt s u f fi c i ent r e l ated " p e r iphe r a l " o r "background" dat a . Graph i c a l pre s entat i on o f dat a i s undoubt e d l y e f fect ive , howeve r two fact o r s n e e d t o b e t aken i n t o account ; f i r s t ly, if the app l i c at i on i s int e r a ct ive , at s ome s t age data w i l l have t o be read f r om the graph , which is o ften not e a s y , and s e cond l y , modi f i e d dat a w i l l have to be reent e r e d , a n d graph ical i nput equ i pment such a s d i g i t i s in g t ab l e t s a r e n e ithe r readi l y , wide l y , n o r che ap l y ava i l ab l e . The p r e s entat i on o f n o n -graph i c a l data i s t h e re f o r e imp o rt ant , a n d a comb i n at i on o f graphical a n d nume r i c dat a i s probably the i de a l ..

(14) 11 3.3. S OF TWARE T O O L PAC KAGE S ; SETS OF COMP UT E R F UNCT I ONS: ( An e x am i n a t i on o f the o r y o f o p e rat i o n o f s o ft ware p ackage s ) .. O n e o f the key p o i nt s t o note from the f o l l owing is the e xtent of ove r l ap between the funct i on s o f fered by the v a r i o u s c ommon PC s o ftware t o o l s . The e x t ent o f ove r l ap i s i l lus t rated i n F igure 1 . A l m o st a l l o f the t o o l s with rudiment a r y progr amming faci l it i e s can emu l at e t h e fun c t i on s o f t h e other t o o l s . F o r e xamp l e , i t i s qui t e p o s s ib l e t o con s t r u c t an exp e rt s y s t e m app l i cat ion u s i n g a datab a s e l angu a g e such a s Asht o n T at e ' s " dB a s e " , though i t i s almo s t c e rt a i n l y more di f f i cult than b y u s i n g a n expert s y s t em she l l . It is l i kewi s e po s s ib l e to c r e a t e an expert s y stem app l i c at i o n u s ing the mac r o p ro g r ammi ng langu a g e s o f the more advanced spre adsheet s . 3.3.1. P rogramming l angu age s. ( 3 GL ) .. T he general purp o s e p r ogramming l an gu age i s undoub t e d l y the m o s t ver s at i l e o f the P C s o ftwar e to o l s , but i t . i s a l s o o n e o f the t o o l s o f fe r i ng the lowe st p r ogramme r p roduct ivity . The ma j o r i t y o f s o ftwa r e t o o l package s a r e o r i ginal l y c omp i l e d from such l anguage s . 3.3.2. D at ab a s e man agement s y s t ems. ( DBMS ) ,. T h e e s s ent i a l fac i l it y o f a f i l e management app l i c at i on is the s t o rage and ret r i eva l o f dat a . T o qu a l i fy f o r the t it le o f database management s y st em , an app l i ca t i on needs t o add t o the capab i l i t i e s o f a f i l e manage r , f ac i l it i e s f o r man ipu l at ing , a s s o c i at ing and l in k i n g data from s e ve r a l f i l e s at o n c e . D at ab a s e managemen t sy stems have b e e n sub j ect ed t o much the o re t i c a l anal y s i s ; Mo s t PC based dat aba s e p a ck age s are b a s e d on E C o dd' s r e l at i onal dat a mode l [ 9 ] . Although DBMS ' s a r e s omewhat more spe ci a l i z ed than a gene r a l p u rp o s e p r ogramming l anguage , many DBMS package s inc lude e x ce l l ent h i gh l eve l p ro g r ammin g languag e s de s i gne d t o a l l ow a dvant age t o b e t ak e n o f the e f f i c i ent fi l e a cce s s fac i l i t i e s . Asht o n T at e ' s "dBa s e " DBMS ' s pr ovide a g o o d examp l e s o f the s e qua l i t i e s ..

(15) DATABASE. SPREAPSHEET. Lin king and jo in in g o f fi le s. Comp lex q ue rie s. In f o rma ti on s t o ra ge. G ra p hi c s , Mode l lin g , in f o rma ti on p re senta tion. Tex t and n ume ri ca l manip u la ti on P rogra m flow con t ro l. In fe ren ce ma c hani s m (en gine ) . Imp lementa ti on o f "Rule s" , ba ckwa r d fo rwa rd chaining.. EXPERT SYSTEM. GENERAL PUEPOSE PROGRAMMING LANGUAGES C3GL ' s). F IGURE 1:. OVE RLAPP ING FQNC TIONS OF SOF TWARE PACKAGES.

(16) 13 3.3.3. E xp e rt S y s t em. " E xp e rt s y s t em s " c ommo n l y comp r i s e an " in fe rence engine '' wh ich ope ra t e s on spe c i a l i z ed data s t o re d i n a " knowl e dge b a s e " . The expert s y stem " in fe re n c e engine " t re a t s the knowledge b a s e " rul e s " a s a s p e c i a l type o f s ub rout ine ( procedure ) wh i ch i s " re s u l t addre s s ab l e " that i s , a subrout i n e wh i ch i s i nvo k e d ( ca l l e d , addr e s s ed ) when t h e r e s u l t it p r o du c e s i s spe ci f i ed . B y cont r a st , i n a convent i o n a l p r o g r ammi n g language ( su ch a s P a s cal ) , p r ocedu r e s a r e " name addr e s s ab l e " , that i s , they are c a l l ed when the n ame o f the p r o c e dure i s speci f i e d . Not e t h i s di st inct i o n ; i n PAS CAL ( fo r e x amp l e ) , a procedu r e i s addre s s ed by re f e r r i ng t o i t s NAME ( i r r e s p e ct ive o f the content s / re s u l t s o f the p rocedu r e ) . For e xamp l e , should the ma i n p r o gr am cont ain t he c o de begin C a l cu l at eOutput end; the p a s c a l p r o gram w i l l r e c o gn i s e " C a l cu l at eOutput " as the name o f a p r o ce dure o r funct i on , and wi l l t h e n find and e x e c u t e " P rocedu r e C a l c u l at eOutput " , o r " Funct i on C a l cu l a t eOutput " . I n the i n ference engine o f a backward cha i n ing e xpert s y s t em , the " p ro c e dur e s " ( RULE S ) a r e addr e s s ed not by the i r name s , but r a t h e r by spec i fy i n g a var i ab l e whi ch i s found in the i r r e s u l t s s ect ion ; F o r e x amp l e , when VP Expert e ncount e r s the " F ind XXX " i n the fo l lowing c o de , it l o o k s f o r a ru l e whi ch h a s " XXX = " i n i t s con c l u s i on ( t he s e ct i on fol l owin g it s " then " s t at ement ) ; that i s , a r u l e whi ch i f pas s e d , wi l l p r o duce a va lue f o r XXX . I n t h i s c a s e such a s e a rch l o c at e s " Ru l e 1 " . " Ru l e 1 " howeve r requ i r e s t he fu l f i lment o f two c ondi t i o n s ( b = 2 , and c= 3 ) in o rde r t o "pa s s " , and only t he va l u e o f " c " i s known . VP Exp e rt the re fore s e e k s a furt h e r ru l e cont a i n i n g " b = " i n i t s conc l u s i o n , l eading t o the evaluat i o n of " Ru l e 2 " . I f " y " is found t o b e e qu a l t o 5 , then " Ru l e 2 " " p a s s e s " , " b " i s a s s i gn e d the v a l ue 2 , " Rule 1 " "pa s s e s " , and the value " s omet h i n g " i s a s s i gn e d t o " XXX " . c= 3 F i nd XXX ; Ru l e 1 if b= 2 AND c = 3 then XXX = " s omething " ; Ru l e 2 if yyy = 5 then b = 2 ; The r e i s a l s o a ve ry s t r ong theore t i c a l s im i l a r i t y betwe e n t he c oncept o f " ru l e s " , a s u s e d b y e xp e r t.

(17) 14 s y s t ems knowl edge b a s e s , and the c o n cept o f funct i on a l dependency (o f non-key att r ibut e s o n key att r ib ut e s ) Th i s within a tup l e o f a (re l at i onal ) dat aba s e . conn e ct i o n has been we l l recogni s e d by the de s i gn e r s o f such e xpe rt s y s tem s he l l s as VP E x p e rt , whi ch p rovide s a spe c i fi c command (INDUCE ) t o c r e at e a s et o f ru l e s dire ct l y from a dat aba s e . Un fortun a t e l y , mo s t P C dat ab a s e i mp l ement at i on s provide v e r y p o o r (i f any ) supp o rt f o r " ke y s " , nece s s itat ing c a re fu l u s e o f t h i s comman d . Det a i l e d i n f o rmat i o n on the the o r y and ope rat i on o f expert s y s t ems can be found in Levine and D rang [ 1 ] , and F r en z e l [ 6 ] . 3.3.4. S p re adsheet. Gene r a l p r o g r amming l anguage s , the i r s l i ght l y mo r e spe c i a l i z ed va r i ant s , dat abas e s , a n d the even m o r e speci a l i z e d exp e rt s y s tem she l l s h ave a l l been sub j e ct e d t o a great de a l of the o r et i cal i nve s t igat i o n . The s p r e adsheet , by cont r a s t , p r o v i de s a very c omp l e x progr ammi ng envi r onment , but h a s app arent l y been sub j e ct e d t o min imal fo rma l inve s t i gat i on . Un l i ke a l l o f t h e oth e r s o ftware p a ck age s whi ch o r i g i n a t e d o n ma i n f r ame comput e r s a n d w e r e p o r t e d to P C ' s , the spre adsheet o r i g i n ated a s a P C t o o l , and i s p r ima r i l y st i l l a P C t o o l (main frame ve r s i on s do , o f cou r s e , exi s t ) . The s ca r c i t y o f formal i nve s t i gat i on a l s o me an s a s c a r c i t y o f fo rmal de f i n i t i o n o f spre adsheet funct i ons ; o b s e rvat i on s hows a c ommo n core o f funct i o n s cons i s t in g o f ; A fixed- s i z e a r r ay o f d a t a e l e �l:ent s , de s i gn e d t o b e h e l d ent i r e l y i n memo r y ; Me ans o f i dent i fy ing and manipu l at i n g s p e c i f i c s e c t i o n s o f t h i s a r r a y (ce l l s , range s , w i ndows , " datab a s e s " ) , A set o f ut i l i t y funct i o n s (u s u a l l y ava i l ab l e v i a pu l l -down menu s ) a l l owing t he u s e r t o manipu l at e (move , c op y , de l e t e et c ) e it h e r the a r ray a s a who l e , o f s e ct i o n s o f it . A "programming l anguage " allowing two t yp e s o f funct i on s ; a/ The de f i n i t i on o f a nume r i c a l r e l at ionship b etween o n e e lement o f t h e a r r a y and any numb e r o f othe r s , b y s imp l y de f i n i n g t h e r e l at i on s h ip formu l a , and att achin g t h i s t o the " t arge t " e l ement a r r ay , and b/ The ab i l i t y t o s t o r e , and exe cut e aut omat i ca l l y , s equenc e s o f the ut i l i t y funct i ons , (a s " macros " ) . A powe r fu l me ans o f pre s enting r e s u l t s , b o t h g r aph i ca l l y , and b y a bu i lt - i n windowing f ac i l i t y , a l lowing the u s e r t o "brows e " t he l ength and w i dt h o f the a r r ay a t any t ime ..

(18) 15 The l imitat i on s o f t he s p r e adsheet a re ; F i rstly , the fact t hat it i s memo r y b a s e d means t hat t he t ot a l qu ant i t y o f data wh i ch can b e h e l d i s l im i t e d ; t h e s p r e ads h e e t i s de f i n i t e l y a f i xed s i z e a rray - maybe l arge , but de fin i t e l y f i x e d . S econdl y , whi l e t h e "macro " l anguage s undoubtedly cont ain the ma j o r fun ct i o n s o f fered by gen e r a l p u rp o s e p r ogramming l anguage s , they a r e i nt e rp re t e d l anguages, l im i t i n g the i r s p e e d , and ( mo r e imp o rt ant l y ) , b e i n g c o n s t r u cted a s a s e qu e n ce o f k e y s t roke s ( re lated to the pul l - down menu s e l e ct i on s , they a r e not o r ious ly d i f fi c u l t t o debug a n d maint a i n . Whi l e the funct i on s ava i l ab l e are gene r a l l y s u f f i c i e n t l y powe r fu l to o f f e r the ma j o r funct i on s o f a pr ogramm i n g l anguage , the r e a l st rength o f the spread s h e e t l i e s i n the area o f dat a p re s ent at i o n , rathe r t h an dat a p r o ce s s i n g ; T he " b r ows i n g " fa c i l i t i e s , the ava i l ab i l ity o f wi ndows and graphi c s fun c ti o n s , and the ab i l it y to ob s e rve the e f fe ct o f changing dat a in one ce l l on the va lue s o f a l l l inked ce l l s , o f fe r s a degre e o f u s e r i nt e ract i o n unp a ra l l e l e d b y o t h e r s o ftwa r e t o o l s . I n t he abs e n c e ( o r at l e a s t ign o r an c e ) o f any formal t h e o r y of s p r e adsheet ope rat i on and p r o g r amming, the s e we r e inve s t i gated very b r i e fl y a s part o f t h i s pro j ect . I t was found that t he e s sent i a l a sp e ct o f spread s h e e t ope rat i on was that , whe r e a s a gene r a l purp o s e p r ogramming l anguage h a s " n ame - addr e s s e d " subrout i n e s /procedu re s , and expert s y s t e m s have " re s u l t - addr e s s ed " s ub rout ine s , the spre adshe e t h a s " unive r s a l l y addre s s e d " , o r " u n condit i o n a l l y addr e s sed" subrout i n e s . That i s , eve r y t ime a dat a i t em is entered t o a s p r e a d sheet , ALL sub rout i n e s ( ce l l f o rmu l ae ) a re ( re ) eva l u at ed . Th i s p r i n c ip l e can b e a l t e rnat i ve l y s t at e d a s ; subrout i n e s i n a p r o gramming l angu age a r e act ivat e d whenever the i r NAME i s invoke d , expe rt s y st em ru l e s a r e a ct ivat e d whenever t h e i r RE SUL T S a r e i nvoked , but s p r e a d sheet c e l l f o rmu l a e a r e invoked UNCOND I T I ONALLY when ever any data is ent e re d . 3.3.5. W o r d P roce s s ing ,. The w o rd pro ce s s ing app l i c at i on i s the m o s t spe c i a l i z e d o f the app l i c at i o n s pre s ent e d , a n d t h e on l y one whi ch i s not a deve l opment t o o l ( s ome WP ' s d o a l l ow mac r o s f o r various o p e r at i o n s t o be s e t up , but t h e s e a r e ve r y l imited i n s cope ) ..

(19) 16 3.4. APPL I CAT I ON S REQU I R I NG INTEGRATED USE O F MORE T HAN ONE S OFTWARE TOOL PACKAGE ; S E LECT I ON O F PACKAGE S AND S TRATEGY .. 3.4.1. Pro spect s for integrat i on .. Note 1 ; thi s s ect i o n i s int ended t o e x am i n e the pro s p e ct s from t he u s e r' s view, rather tha n t he ava i l ab i l i ty o f t o o l s /t e chni que s . N o t e 2 ; The po s s ib i l it i e s for integrat i on w i t h other p ack age s , and e s p e ci a l ly graphics a n d commu n i cat i on s p ackage s h a s n o t b e e n addre s s e d here ; I n the ca s e o f the commu n i cat i on s package s , t h i s i s becau s e from a u s ers p o i nt o f view, they are primari l y an a l t e rnat i ve me ans o f dat a entry , and a s s uch s h o u l d the o re t i ca l ly need be n o more t h a n another s in g l e command opt i on within an app l i cat i o n . I n t h e ca s e o f graphi cs p ackage s , the fun ct i o n s o f fere d are far from st andardi z e d , varying b etween p ack age s whi ch a re s imp l i f i e d CAD appl icat i on s , and s u ch things a s grap h i cs t o o lbox e s supp l i e d with 3 G L programm i n g langu a ge s . The l atter cou l d de f i n i t e ly b e u s e d t o advant age in the ca s e o f an app l i cat i on deve l op e d u s ing (eg) TurboPa scal . Note 3 ; mo s t s o ft ware pack age s have f a ci l it i e s for " cal l in g " other p ackage s /b atch pro grams , s o i f the o n l y capab i l ity l ack ing in a p rop o s e d p ackage i s ( fo r examp l e ) a part i cu l ar mathemat i ca l funct i o n , t he eas i e s t rout e may be t o dev e l op t h i s in a 3 GL programming l a·nguage , and ca l l the re sult i n g . EXE f i l e when requ i re d . 3 . 4 . 1 .1 S pre adshe e t /Dat aba s e A s has been noted i n s ect i on 3 . 3 . 4 above , the strengt h of the s preadsheet l i e s i n its ab i l it y t o pre s e nt dat a ; o n e o f i t s we akne s s e s i s that , b e i ng memory b a s e d , and o f a f i x e d s i z e , the quant i t y o f dat a whi ch can be s t o red i s l imited . Thi s weakn e s s s ugge s t s the p o s s ib i l i ty o f comb i n ing the dat a st orage and retri e v a l capab i l it i e s o f a dat aba s e with the dat a pre s e nt at i on st rengths o f t he s pre adsheet . Spre a d s he et s genera l ly have few bu i lt - in s e curity feature s ( the ab i l it y to carry out " what - i f " e xe rci s e s t o e x p l ore the e ffect o f modi fying dat a i s counte d a s one o f the spre adshee t ' s s t rengt h s ) ; however u n l e s s very care fu l ly contro l l e d , thi s faci l ity can re s u l t i n a u s e r l o s ing a l l record o f what dat a i s h i st o rica l ly correct , and what dat a i s the re s u l t o f hyp o t he s e s . I n an app l i cat i on where t h i s s ituat i on i s a p o s s ib i l it y , a dat ab a s e cou l d be u s e d t o maint a i n an " authori z e d vers i o n " o f the dat a , ava i l ab l e f o r re l o a d i n g t o the spre a d s he et as require d ..

(20) 17 3 .4 .1 .2 Spreadsheet with E xpert S y s t em ( app l i cat i o n ) There i s a deg r e e o f ove r l ap betwe e n t he app l i cat i o n s for wh i ch a spre a dsheet wou l d be the obv i o u s cho i ce , and tho se for which an e xp e rt s y s t em she l l wou l d come to mind; both a r e u s e d f o r e xp l o r i n g hyp othe s e s , the spre adsheet b e ing more s u i t ab l e f o r cas e s whe r e t he ru l e s a re s imp l e r , and t he quant i t y o f dat a i s l arge r , whe r e a s expert syst ems a r e pre f e r r e d whe re t he quant ity o f dat a i s s ma l l e r , a n d t h e ru l e s a r e mo r e comp l e x . Cas e s whe r e p a rt o f an app l i cat i on l e ans t oward the e xpert system t e r r i t o r y , and o the r p a r t s o f the app l icat i on l e an t owards tha spreadsheet , a r e common . One such app l i cat i on forms t he ma i n s ub j ect o f t h i s t he s i s . 3 .4 .1 .3 Expert System ( app l icat i o n ) with D at ab a s e The the o ret i ca l b a s e s f o r datab a s e de s ign ( an d p a rt icu l a r l y r e l at i o n a l dat ab a s e de s i gn ) have b e e n we l l e st �bl i s hed , howeve r a l l t o frequently t h e r e s u l t o f a r igorous mode l l ing and normal i z ing exe rci s e i s a s omewh at " fr agme n t e d " dat a s t r ucture con s i s t i ng o f a l a rge numb e r of f i l e s , requ i r i ng a l a rge qu ant i t y o f dat a t o co r r e ct ly and fu l ly de s cr ibe the app l i cat i on . The pract i ca l prob l e m which t h e n ar i s e s i s that o f decidi ng whethe r the combinat i on o f the dat a cap t u r e e ffort , p l u s the e f f o rt and t ime requ i re d t o deve l op and app l y e qu a l l y an e qual ly r i go r o u s dat a ana lys i s , i s p r a ct i cal a t a l l ( an d whether i t i s j u s t i f i ed b y the value o f the app l i cat i o n ) . Two oppo rtun i t i e s for int e grat i on of the s e t yp e s o f pack age have b e e n i dent i f i e d. F i r st l y , the p o s s ib i l it y o f u s ing an expert s ystem app l i cat i on a s an " inte l l igent int e r fa ce " to a d a t ab a s e e x i s t s . S e co n d l y , t he s im i l a r ity betwe en dat ab a s e de s i gn t he o ry , a n d t he t he o ry o f e xp e rt system ru l e s ( s e e s e ct i o n 3 .3 .3 ) cou l d b e exp l o it e d to a l l ow i n fe rence o f e xp e rt system r u l e s di rect ly from dat aba s e fi l e s ( an d , b y r e t u r n i ng i n forma t i o n t o the dat aba s e , a l l ow the con s t ruct i o n o f an app l i cat i on whi ch " l e a rn s " ) . 3 .4 .1 .4 W o rd p r o ce s s ing with Spreadsheet , and dat ab a s e The a l l owab l e l ength o f s t ring var i ab l e s , s i z e o f dat ab a s e f i e lds , and s i z e o f s p r e adsheet ce l l s ( w i t h t he e x cept i on s , s uch a s Sympho n y ) set by o t h e r p ackage s o ft en p l ace s eve r e l imitat i on s on the quant i t y o f t e xt whi ch can b e s t o r e d , s o the ab i l ity to i n t e g r a t e a word p r o ce s s o r w i t h other p ackage s is ve ry de s i r ab l e . 3 .4 .2. Methods o f appr o aching int egrat i o n. 3 .4 .2 . 1 S e l e ct and u s e an integrat e d s o ftwar e p r o duct Int egrated s o ftware product s , such a s L o t u s S ymphony, IBM ' s Go l dengat e ( wh i ch has the added feature of commun i ca t i on faci l i t i e s t o s ome ma i n f r ame app l i cat i on s ) , and t he budget p r iced PF S " F i r st.

(21) 18 Choice " , att empt t o p ro v i de s eve r a l funct i ons i n o n e fu l l y integrated p ackag e ; typ i ca l l y the s e funct i on s include the n o rmal spreadsheet funct i on s , p l u s a fa i r l y go o d file man agement s y s t em , and a l i mited word p r o ce s s ing fac i l ity . Commun i cat i o n faci l i t i e s are a l s o The main a dvant age o f s uch frequ e n t l y i n c l uded . pack a g e s i s t hat the int egrat i on (both o f dat a and ope r a t ion ) is a l re ady done . The d i s advant ages l i e i n the spreadsheet o r igins o f the pack age s ; the " da t ab a s e " fac i l it i e s are memo ry r e s i dent , l imit ing t he i r cap a cit y , and t he "programming l anguage " i s s p r e adshe e t mac r o s wh i c h , wh i l e p owe r ful , a r e di fficu l t t o maint a in . A further p r ob l em i s t hat a lt hough t h e s e packages a r e " i ntegrat e d " , the fe a t u r e s conce rn e d a r e bu i l t - in ; i f t h e fe a t u r e s requ i r e d for the p r op o s e d i n t e g r ated app l i cat i on a r e a l l ava i l ab l e , t he r e i s n o prob l e m ; i f t hey a r e n o t , then t h e deve l op e r i s l i t t l e bet t e r o f f t han with s i n g l e - funct i o n package s . A de s c r ipt i o n o f t he faci l it ie s o f fered by Lotus Symphony can be found in " The Symphony Re feren ce B o o k " [3 ] ; informa t i o n on mac r o deve l opment and u s e can be found i n " the Lotus Maga z i n e " [7 ] , and mo re t e chn i c a l det a i l regarding fi l e f o rmat s e t c c a n be found in " Lo t u s F i l e F o rmat s " [ 8 ] . 3 . 4 . 2. 2. Programming l angu age ( 3 G L ' s ) " t o o lb o xe s " . S ome o f the more popu l ar p r o gr amming l angu age s ( 3 GL ' s ) have an exten s ive l ibrary o f app l icat i on modu l e s ava i l ab l e ; a g o o d examp l e i s B o r l and' s Turbo Pa s c a l , whi ch is s o l d with the s ou r ce code of a s imp l e s p r e a d s heet included i n t he pu rch a s e price , and for which " nume r i ca l methods " , " da t ab a s e " , and " g r aphic s " t o o l b o x e s ( w i t h s ource code ) are re adi l y ava i l ab l e . F o r a p r o grammer fami l i ar with TurboPa s c al , a s s emb l ing and l in k i n g such modu l e s to p r ovide a n app l i cat i o n which o f fe r s some o f the faci l it ie s o f a dat aba s e and a s oph i s t icated spreadsheet wou l d b e qu i t e p o s s ib l e , and p ackage f o r ma rket ing p u rp o s e s wou l d p rovide a " t i dy " ( i e , w i t h few D O S f i l e s , n o l i cencing prob l ems , and ins t a l l at i on p rocedu r e s a l r e ady supp l i e d ) .. 3 . 4 . 2. 3. Use i ndividu a l s t andard s o ftware p a c k a ge s . The final opt i on i s t o make u s e o f s eve r a l st andard s o ftware p ackage s , and t o u s e e ach acco rding to i t s part i cu l a r st rengt h s ( a s opp o sed t o capab i l it i e s ) . N o t e ; an imp o rt ant variant o f t h i s opt i on i s t o u s e a s et o f individu a l package s ( typ i c a l ly from t he one s u p p l i e r ) , whi ch a r e speci f i ca l l y de s igned t o w o r k t oget he r . An examp l e o f this app r o ach can be found in the VP I n fo , VP P l ann e r , and VP Expert p ack age s , a l l supp l i e d by " Pape rback s o ftware " . These p ackage s a l l ow ( fo r e x amp le ) the operation o f the VP P l ann e r spre a d s heet from withi n a VP Exp e rt app l i cat i o n ..

(22) 19 3.4.3. I nt eg rat ion o f ope rat i o n. 3 . 4 . 3 . 1 ''Aut omenu " ( o r e qu ival ent ) : See F i gure 2A . The " Aut omenu " p ack age a l l ows the co n s t ruct i o n o f a cu st omi s ed menu s y s t em , from which app l i cat i o n p ackage s can b e s e l e ct e d and run with a m i n i mum o f keyst r o ke s . The "Aut omenu " package i s ava i l ab l e e i t h e r comme rci a l l y or a s pub l ic domain so ftwa re . " F l ashup " i s s imi l a r i n ope rat i o n t o "Aut omenu " , but p o s s ib l y even fast e r and s imp l e r . 3 . 4 . 3 . 2 U s e o f Micro s o ft " Wi ndows " , " D e sqv i e w " , o r " S o ft ware Carou s e l " ( a l l about $2 0 0 - $3 0 0 ) ; S e e F i gu r e 2 B . The s e p r oduc t s all ow a numb e r o f app l i cat i o n s t o b e d i s p l ayed s imu l t a n e o u s l y wi thin d i f fe r ent " w i ndows " ; o n l y o n e p roduct i s act u a l l y " act ive " at any o n e t ime , but the s w i t ching between p r o duct s i s s imp l e , and t he ab i l ity t o retain the r e s u l t s o f act ivity o n o n e app l i cat i o n , whi l e ope r at ing o n another i s very valuab l e . S everal o f the s e p r o duct s suppo rt ( va ry i n g degre e s o f ) d a t a e xchange between t h e app l icat i o n s b e ing d i sp l ayed . 3 . 4 . 3 . 3 U s e o f one o f t he app l i c at i on package s t o con t r o l u s e o f o the r s ( v i a internal menu s y s t e m , a n d D O S ca l l s ; S e e F i gu r e 2 C . The l imitat i on o f thi s method i s that t he cho s e n app l i ca t i o n r ema i n s i n l o aded i n memory ; i f t h e cho s e n p ackage i s l a rge , l it t l e memo ry space rem a i n s i n t o whi ch furthe r pack age s can be l o aded ) . 3 . 4 . 3 . 4 Us e o f a t rue mu lt i t a s king Ope r at ing Sys t em . Po s s ib l e cho i ce s ( fo r a PC ) incl ude XENI X ( o r othe r propr i e t ary UNIX imp l ementat i o n ) , O S /2 o r Concu r re n t CP/M 3 8 6 ..

(23) .... MENU PROGRAM. ...... -. -. F IGURE 2A:. EXP E RT SYSTEM A P P L I CA T I ON. ,.. ,. -. ..... DATABA S E A P P L I CA T I ON. .... SP REA D SHEET A P P L I CA T I ON. Use o f "AUTOMENU" ,. /. o r e quiva lent.. MICROSOFT "W I ND OW S" , " D E SQV I EW" , EQU IVALENT.. DA TABA SE A P P L ICAT ION. ---EX P ERT SY STEM A P P L ICA T I ON .... "ACT IV E" A P P L ICAT I ON. F IGURE 2B:. Use o f "A ct i ve w indows".. ..... A P P L ICA T ION IIAII. �. -. -. -. -. SPR EA D SHEET A P.? L I CA T I ON. -. " MENU". -. � -. I. A P P L I CA T I ON "B". A P P L I CA T I ON " C". F I GURE 2 C: " Men u" a s pa rt o f one app l i cat i on.. F IGURE. 2:. INTEGRATI ON OF OPERAT ION. R. O.

(24) 21 3 . 4 .4. I nt egrat i on o f dat a. P r o duct s such as VP E xpert have ext e n s ive faci l i t i e s for d i re ct imp o rt o f dat a used by o t h e r product s . P r oduct s such a s S ymphony , dBa s e e t c h ave s omewha t mo re l im i t ed s uch faci l i t i e s . S e e F i gur e 3A . It i s s u spected t hat i n the ca s e o f VP Expert , t he ab i l i t y t o import ( eg ) spre adsheet dat a i s r e s t r ict e d b y ava i l able memo ry space , though t h i s has not b e e n con f i r me d . Othe r opt i o n s include the u s e o f interm e d i at e dat a fi l e s , in. a format which can b e wr itt e n t o/re ad from by a l l s o ftware package s i nvo lved; AS C I I a n d D I F fi l e s b e i ng the mo st common ( thou gh dB a s e f i l e s a r e al s o u s e d b y many app l i cat i on s ) . Thi s i s i l lu s t r at e d i n F i gure 3 B ..

(25) E:l;EEBI SYSTEM APELICATION. I\. 1\. data reque s t. .... -. SEBE:ADSI::IEEI AEELIC8IIQN. -. -. -. -. -. -. -. -. -. AEPLICAIION DAIA. da t a flo w -. FIGURE 3 A: D a t a held w i t h in one app l i cat ion, a c cce s sed dire c t ly by o t he r app l i ca t ion s. EXPERT SYSTEM APELICATIONS. SPBEADSI::IEE:T AEELICATIQNS. /i\. I�. -. QAIA EILE ASCII t�;�S;t' dBa�e Ill. lll..E... SQE �t�:; -. FIGURE 3 B: Data he ld in separate data f i le( s).. F IGURE 3 INTEGRAT ION OF DATA.

(26) 23 3 . 4 .5. Eva l u at i on and s e lect i o n o f package s and appro ach method .. 3 . 4 . 5 . 1 I nt egra t i on appro ach The s e l ect i on o f the metho d o f appro a ch ( from the opt ions pre s ent e d in s ect i on 3 . 4 . 2 above ) is primari l y on the ba s i s o f overa l l co st , however it i s e s s ent i a l t o appreci a t e that overa l l co s t i nclude s deve l opment co s t . D eve l opment co s t s common l y outwe i gh the cap i t a l co s t o f p ackage s i nvo l ved . Other facto rs include t ho s e a s s oci at e d w ith market ing ( for e x amp l e , i s it e s s ent i a l t o market t he app l i cat i on a s a s ingle fi l e ) , ava i l ab l e deve lopment t ime , and capabi l i t y ( does dat a vo l ume pre clude the use o f a spre adshe et?) . An addi t i on a l pract i ca l cons ide rat i on i s the p ri o r commitment t o a part i cu l ar s o ftware p a ckage . . I f , for examp l e , a s e ct i on of the app l i cat i on h a s alre ady b e en deve l oped u s ing a spre adshe e t , then the u s e o f individual p a ckage s w i l l t e n d t o be favoured a s the appro ach t o i n t e grat i on . 3 . 4 . 5 . 2 Eva luat i on o f p a ck age s . Overa l l co st ; Overa l l co st s include s in g l e l i cence p ackage co s t s , and the amort i s at i on of deve l opers ' vers i on co s t s , and deve l opment co st s . " i nt e grab i l i t y " ; S ome package s have ext e n s ive faci l i t i e s wh i ch make i nt egrat i on easy ( fo r e xamp l e , VP Expert h a s p art icu l ar l y s imp l e funct i ons for u s ing dat aba s e , spreadsheet and t ext f i le s , a s we l l as for ca l l ing other p acka ge s ) , other package s h ave few such faci l i t i e s . Ava i l ab i l ity of deve l oper' s vers i o n s ; I f a l l /any o f t he standard s o ftware p roduct s u s e d i n the app l i cat i on d o n ot have a deve l opers ' vers i on , (with a l i cence a l l ow i ng dis tribut ion o f runt ime modu l e s ) , then s evera l prob lems ari s e ; firs t l y , a s ingl e - l i ce nce copy o f the o f fending s o ftware p ackage w i l l n e ed to be s o l d with each " integra t e d app l i cat i on " , and s e condly, copy s e curi t y become s d i f ficu l t t o contro l . I n pract i ce the mo s t s eri o u s problem o f t h i s t yp e o ccurs w i t h spre adshee t s , whi ch do not common l y have deve l opers ' vers i on s ava i l ab l e . The author is aware o f o n l y one spre adsheet comp i l e r , " @l ibert y " , and t he cap ab i l i t i e s o f thi s product are unknown . Hardware requ i rement s ; One fact or wh i ch needs t o b e con s i dered very care fu l ly i s that commerci al s o ftware w i l l be attract ive t o users o p e rat ing a wide vari e t y o f hardware ( w i th di f fe ri ng memory cap acit y , di s k con f igu rat i on and cap acity, and proce s s or t ype and cap abi l i t y ) and periphera l s . Alt hough the co st o f h ardware con t inue s t o decre a s e i n re lat i o n t o capab i l ity a n d mo re s op h i s t icat e d periphera l s b e come readi l y ava i l able , an app l i cat i on which requ ire s very.

(27) 24 speci f i c o r s ophi s t i cated cap ab i l i ty wi l l nevert he l e s s b e at s om e dis advant age i n the marketpl ace . 3 . 4 . 5 . 3 As s i gnment o f funct i on s . As suming that t he deci s i on has been t aken t o deve l op a n app l i cat i on by integrat i ng the capab i l i t i e s o f s evera l s o ftware p ackage s , i t i s nece s s ary t o decide how to d i v i de the funct i ons between the vari o u s pack age s . T h e que st i on i s b y n o mean s s imp l e , s i n ce there may b e a very h i gh degree o f overl ap o f CAPAB I L I T Y b etwe en the p ackage s . Po s s ib l e crit eri a for a s s ignmen t o f funct i ons i nclude ; Keystro ke s ; Wh i ch package can accomp l i sh the t a s k with the m i n i mum number o f keystrokes ( an imp ort ant con s i derat i on for the u s er) . Spe e d ; Whi ch package c a n e xe cute the funct i on fa s t e s t . E a s e o f deve l opment ; I n whi ch pack age can the funct i on m o s t e a s i ly be deve l oped ( t ak ing account of ava i l ab l e programmer s k i l l s etc) . Note that a statement t o t he e f fect t h at " i t i s e a s i er t o imp l ement app l i cat i o n "A" u s i n g l anguage/s o ftware package " B " , rat her t hat l an guage/s o ftware p ack age " C " " i s o n l y o f value i f the proposed pro grammer has equal l e ve l s o f s k i l l i n t he u s e o f " B " and " C " , and i n pract i ce t h i s i s s e l dom so . I t wou l d there fore b e more u s e fu l t o s t at e that " a l ower l eve l o f programmer e xpert i s e i s re qu ired t o imp l ement app l i cat i o r. "A" i n l anguage " B " t han i n l anguage " C " " . I n pract ice , i t i s sugge s t e d that t h i s is the crit e ri a mo s t l i k e l y t o be u s e fu l . Logica l group ings o f funct i on s ; N o matter how good the int egrat ion o f operat i on i s , i t i s un l i ke ly t o b e accept ab l e t o ca l l one p ackage from w i t h i n a l o op execut i n g within a n o t her package , s imp ly to use the f i rs t pack age ' s s up e ri or mat hemat ica l funct i o n s . The f i na l criterion h a s been found t o b e t he mo s t common l y app l i cab l e ..

(28) 25 4. ENERGY C O S T MANAGEMENT ; AN APPL I CAT I ON FOR I NTEGRAT I ON OF S TANDARD S OFTWARE TOOL FUNC T I ONS. CHAPTER SUMMARY The fo l l owing s e ct i on b e g i n s with a b r i e f de s cr i p t i on o f the sub j ect o f Ene rgy C o s t Management , t he u s e o f a spreadsheet app l i cat ion deve l oped by Pro f Mont e i t h o f Mas sey Un i ve r s i t y t o a s s i st with the ana lys i s and managemen t of ene rgy co s t s . The f i n a l s e ct i on comp a res the comput e r funct i ons r e qu i red f o r E CM w i t h t he funct i ons ava i l ab l e from s t andard s o ftware p ackage s , and select s addit i on a l so ftwa re p ackage s . CHAPTER CONTENT S ENERGY C O S T MANAGEMENT ; AN APPL I CAT I ON FOR I NTEGRAT I ON OF S TANDARD S OFTWARE T OOL FUNC T I ONS 4 .1 I NT RODUC T I ON TO ECM 4 .1 .1 The concept o f ene rgy cost management 4 .1 .2 Ene rgy co s t i ng b a s i cs Pr i ncip l e s o f ECM 4 .1 .3 4 .1 .3 .1 The ana l ys i s o f h i st o ri ca l u s age pat t e r n s 4 .1 .3 .2 Pre d i ct i on o f future ene rgy u s age 4 .1 .3 .3 ·Analys i s o f co s t r educt i on me a s u re s 4 .2 ENERGY COST MANAGEMENT U S I NG LOTUS S YMPHONY 4 .2.1 App licat i on modu l e s App licat i o n funct i o n s 4 .2.2 Input s and Output s 4 .2.3 4 .3 ENERGY COST MANAGEMENT U S I NG MULT I PLE SOFTWARE PACKAGE S 4 .3 .1 A compari s on o f ECM t a s k s and s o ftwar e package funct i on s 4 .3 .2 S e l ect i on o f integrat i on app r o ach ( i ntegrat i on o f ope r at i on , dat a ) 4 .3 .3 S e l ect ion and eva l u at i on o f s o ftware p ackages ( genera l ) . 4 .3 .3 .1 S e l e ct i o n o f p ackage s t o extend the Lotus S ymphony ECM app l i cat i on. 4 .3 .3 .2 S e l e ct i o n and eva luat ion o f p ackage s , as suming n o p r i o r commitment t o Lotu s Symphony. 4 .3 .4 As s ignment o f funct i on s t o pack age s . 4.

(29) 26 4.1. I NTRODUCT I ON T O ECM. 4.1.1. The concept o f e n e rgy co st man agement. M i n imi z ing the co s t of energy can b e appro ache d from t wo dire ct i on s ; reducing the t ot a l energy u s age , and MANAG ING t h i s energy u s age i n s uch a way a s t o m i n i m i z e t ot a l cost s . The the ory o f m i n imi z ing t o t a l energy u s age i s we l l k nown and document e d (much o f th i s t he o ry i s ve ry clo s e l y l i nked with cl a s s i cal thermodynamics and heat t ran s fer the ory ) , and the techn i qu e s are wide l y pract i ced . T he reader i s re ferre d to the " Fue l E f f i ci en cy Boo k l et s " [1 1 ] , for i n format ion on t h i s s ub j e ct . B e cau s e o f the way i n wh ich e l ectrical e nergy i s s o l d , the tot a l co st i n curred by t h e con s ume r i s i n f l ue nced even more s t rongly by t he t ime -d i s t ribut i o n o f t he energy u s age , than b y t h e t o t a l qu ant i t y o f energy u s e d . The sub j e ct o f ECM i s the MANAGEMENT o f t h i s t ime -di stribut i o n of energy u s age , and t he end re s u l t i s the min imi z i ng of t ot a l ( l ong t erm , a s we l l a s s ho rt t erm ) energy co s t s t o the u s e r . Ri s i ng energy co st s have acqu ired a l ong h i s t o ry , and it i s there fore surpri s ing that the management o f energy co s t s h a s o n l y recently come t o att ract a s imi l ar de gree o f e f fort t o that whi ch h a s b e e n e xpended on the reduct i o n o f energy us age . T h e import ance o f e n e rgy co st man agsrnent st erns from two princip l e s ; F i rst ly, energy charge s , and in part i cu l ar e l e ct ri ca l e n e rgy charg e s , vary gre a t l y and hence t ot a l energy co st s to an organ i s at i on can b e very s ign i fi cant ly a f fe ct e d b y the p l an n i ng ( management ) o f energy us age ( s e e "An E xp e rt System Appro ach t o Indu s t r i a l Energy U s e Man agement [ 1 2 ] ) ; S e co n d l y , energy co s t s are a ma j or co st e l ement i n many operat i ons , o ft e n e x ce e d i ng the ove ra l l pro f i t margin . The man agement o f energy co s t s has t here fore t he potent i a l o f imme d i at e l y incre a s i n g t ot a l p ro f i t marg i n s b y a l arge fact or , at the e xpe n s e o f minimal out l ay . 4.1.2. Energy co s t i ng b a s i cs. E n ergy suppl y authorit i e s common l y cal cu l at e t ot a l e l ect ri cal energy co s t s b y summing t he re s u l t s o f two type s o f charge rat e s ; a un it charge rate ( t ar i f f ) cal cu l ated in $/kWh , summe d cont inu o u s l y over t he charg i n g period ( intended t o cover t he co s t o f energy u s e d ) , and a Max i mum D emand charge rat e , ca l cu l at e d o n t h e b a s i s o f $/ kVA b a s e d o n t h e p e a k kVA drawn over any 3 0 minute period during the charg ing p e ri o d ..

(30) 27 El e ct r i city s upply authori t i e s commonly have a number of t ar i f f stru cture s , one of whi ch is s e l e ct e d at the t ime t he conn e ct i on cont ract i s agre ed . 4.1.3. Princip l e s o f ECM. T here are three e s s ent i a l a sp e ct s o f e n e rgy cos t management ; The analys i s of (past ) e n e rgy u s age pattern s , a/ b/ The i dent i fi ca t i on of t he pre s ent s i tuat i on , le ading t o the predict i on o f fut ure u s age pat t ern s , and , cl The ana lys i s o f pos s ib l e means o f reduci ng overal l energy cost s . The s e are i l lus t rat e d in F i gure 4, and w i l l now b e exami n e d i n t urn ..

(31) Maximum demand fo r day. Demand. lkYhl. Figu re 4A:. Acccurate appreciation of cu r rent position.. Monthly consunmtion Units ..!..l:Qihl. Figure 4B·. Prediction of future demand. Maximum demand for day. Demand. Target maximum demand. �. Max pem Reduction 30kVA Projected saving I year = $50.000 =. Figure 4C· Analysis of cost reduction proposal s. FIGURE 4:. PRINC I P LES OF ENERGY CO S T MANAGEMENT.

(32) 29 4 . 1 . 3 . 1 The an a l y s i s o f h i st o r ica l u s age p at t e r n s The pat t e rn o f ene rgy us age o f a l a rge o rgan i s at i o n is an e xt r em e ly comp l e x one ; t he ope rat i on o f eve ry s ing l e component o f the ove r a l l p at t e rn h a s i t s o wn s e t o f con s t ra i nt s , many o f wh i ch i n t e ract with tho s e of othe r comp o nent s . By ca r e fu l ana l y s i s o f the ove r a l l pat t e rn , u s e fu l l arge sca l e e ff e ct s can b e The ana l y s i s ident i fied, and t h e n u s e d to advant a ge . wi l l b e conce rned with : t he strengt h o f the cycl i c comp onent s o f u s age , hou r l y , diurn a l , week l y , mont hl y , and s e as onal ( ye a r l y ) ; t h e occu r r e n ce and h e i ght o f p e a k demands , the " b ackground" l o ad ( co r r e s p o nding t o equ i pment on 24 hour ope ra t i on) , and the patt e rn s o f demand a s the y are co r r e l ated with w o rk and bus i ne s s pat t e rns . 4 . 1 . 3 . 2 Predict i o n o f fut u r e ene rgy u s age The mo st imme d i at e u s e for the unde r s t anding o f the p attern o f ene rgy u s age s o g a i n e d , i s f o r the accu rate p r e d i ct i on o f future energy co s t s . Thi s p r e d i ct i on i s nece s s ary both in o rde r t o p r e p a re accu r at e ca s h f l ow p l an s , and a l s o t o a l l ow i n fo rmed economic de ci s i on mak i n g rega rdin g e ne rgy co s t s av i ng mea s u re s . 4 . 1 . 3 . 3 Anal y s i s o f co s t r educt i on me a sure s Met hods o f r e ducing ene rgy co s t include ; Ene rgy s aving a/ The s imp l e st method of reducing ene rgy co s t s i s s imp l y t o re duce the n e t t ene rgy u s age , e g b y the i n s t a l l at i on o f i n s u l at i on to reduce he at i n g and coo l ing co st s , turning 6 f f idl ing e quipment etc . The bene f i t s o f s u ch me a s u r e s are we l l kn own and app r e ci ated . b/ MD Cont r o l I t i s qu i t e common t o find t h a t the l ar g e s t s ingle co s t i ncurred by an e le ct r icity u s e r is that due t o t he Max imum Demand charge l ev i ed by the di s t r ibut i on aut ho r ity . As such , max imum demand i s a p r ime candidate f o r co st cont r o l l ing me a s u re s . One approach t o MD cont r o l i s t o i n st a l l a s imp l e Max imum D emand l o ad shedding cont r o l l e r , de s i gned to t u rn o f f s e l ect e d l oads should the t o t a l demand exce e d s ome p r e p r o g r ammed l eve l ; t he d rawback a s s o c i at e d w i t h s u ch devices i s that they a r e ( at l e a s t unt i l r e ce nt l y ) cap ab l e o f o n l y l im i t e d i nt e l l igence i n the s e l e ct i on of whi ch devi ce s to swit ch o f f , and have n o mean s o f account ing f o r the r e l at i ve imp o r t a nce o f the p r o ce s s con s uming the powe r . A more con s t ruct ive app r o a ch , and one which i s l i k e l y t o a l l ow much great e r l e ve l s o f MD redu ct i on to f i n d management favo u r , is that o f care fu l ly re s chedu l i n g t h e var i o u s l oads t h roughout the day/month, i n such a way as t o m i nimi z e t he MD . S uch r e s chedu l ing needs t o b e g i n with an examinat i on o f the cur rent dai l y l o ad patt e rn s , and a det a i l e d know l e dge o f t h e inte rdependenci e s o f equipmen t , l ab ou r , and raw mat e r i al s etc within the o rgani s at i on ..

(33) 30 Two a lt ernat ive means o f reschedu l ing con s umpt i o n t o r e duce Max i mum Demand a r e i l lu s t r at e d i n F i gu r e s 5 and 6..

(34) Lo ad re s chedu led. Old Max Demand. Load. Demand ( kVA). 0 0: 0 0. 12. F ig u re 6 B :. 00. D a i ly l o ad p a t t rn. 24 : 00 i o r t o l o ad. re s chedu l in. O ld Max . Demand. Ne w Max .. Demand ( kVA) .. 1 2: 0 0. 00 : 00 F i g u re 6 B :. F I GURE. 5:. Demand. 24 : 00. D a i ly load p a t te rn pr ior to load re s chedu l ing. LOAD RE S CHEDQLING TO REDUCE MAX IMUM DEMAND.

(35) Max Dem. ( kVA ). Same. No te :. ( h igh ) M D for ea ch MD char ge per io d. The s a me p ro ce s s ca u se s t he. ( h i g h) MD char ge. du r in g e a ch M D cha rge pe r io d. Jan. . . Mar Figure 7 A :. Max Dem. Ap r. . .. Jun. Jul. . .. Sep t. Oct. . .. De c. Lo ad pa t te rn pr io r to re s chedu l in g. ( kVA ). Sa me MD fo r one cha rge per io d. Re duce d MD for three char ge per io ds. A l l pe a k p ro du c in g. w i t h in one M D charge pe r io d Jan. . . Mar F igu re 7 8 :. Ap r. . . Jun. Jul. . .. Sep t. Oct. . .. De c. Lo ad pa t tern a fter re s chedu l in g. F I GURE 6 : THE EFFECT OF CONCENTRAT ING PEAK-PRODUCING PROCES SES INTO ONE MAXIMUM DEMAND CHARGE -PERIOD.

(36) 33 S i nce the prima ry purp o s e o f the max i mum demand cha rge i s to a l low the s upp ly autho r i t i e s t o recover the i r e qu ipment co s t s ( a s opp o s e d to cove r i ng the purch a s e of t he bu l k p o we r from t he gen e rat i on organ i s at i on s ) , and s i nce equipmen t co s t s a r e re l at e d t o p e a k v o lt age and cu r rent rat i ngs , max imum demand i s me a su r e d i n kVA, rathe r than kWh . A po o r p o w e r fact o r incu r s a he avy pen a l t y i n thi s way , and mak e s the i n s t a l l at i on of powe r fact o r co r r e ct i on e qu ipment imp o rt ant . The degree o f powe r fact o r co r re ct i on needs t o be the sub j ect o f an economic decis i on , b a l anci ng equ ipment l i fet ime and cap i t a l co s t aga i n s t annua l s av i ngs . cl. Re s chedu l i ng o f consumpt i on The s econd pr imary component o f a t yp ic a l e l e ct r i c i t y t a r i f f i s the u n i t co s t , ( ca l cu l at e d i n $/ kWh ) , and i t i s common t o find t hat t h e u n i t cha rge rat e var i e s by a fact o r o f 2 . from one t ime o f day t o t h e n e xt . Re s chedu l ing a l l ope r at i ons t o t h e sma l l hou r s o f t he morning may we l l not b e e i the r p ract i ca l , n o r economi ca l ly de s i r ab l e ( due t o such fact o r s a s p e n a l l ab o u r rate s ) , but the r e s chedul ing o f s ome l o a d t o l ow t a r i f f t ime s i s a pot ent i a l source o f l ar ge s av i ngs . d/. S e l e ct i on o f a l t e r n at ive t a r i f f s t r u ct u r e s As h a s been ment i oned prev i o u s ly, s upp l y autho r i t i e s common l y h ave a numb e r o f t ar i f f s t ructur e s , s ome o f wh i ch may o f f e r di s t i n ct advant age s t o a u s e r w i t h a p a rt i cu l a r l o ad p attern . Even i f the crit e r i a u s e d by the s upply aut ho r ity for s e l e ct i on o f a t ar i f f i s cl ear , changes i n the natu r e o r p ract i ce s o f an o r g an i s at i on may o ffer opp o rtunit i 2. s f o r reque st i n g t hat an a l t e rnat ive t ar i ff b e u s e d .. I n t he ca s e o f l arge con s ume r s , it may b e p o s s ib l e t o negot i at e a one - o f f t ar i ff ; i n the ca s e o f very l arge con s um e r s it may even be p o s s ib l e to negot i at e d i r e ct l y w i t h generat i on autho r i t i e s . e/. S e l e ct i on o f a l t e rnat ive ene rgy s ou r ce s . Whe r e s upp l i e s o f l ow co st a lternat ive fue l e x i s t , the s e may o bv i ous ly b e e xp l o it e d t o reduce o ve r a l l energy co s t s ; opt i o n s r ange from the u s e o f l oca l l y ava i l ab l e b i omass f o r heat ing, t o the con s t ruct i o n o f a comb ined cycl e powe r s t at i on t o ut i l i s e g a s ava i l ab l e o n a " u s e i t o r l o s e i t " cont ract u a l b a s i s ..

(37) 34 4.2 EVALUAT I ON OF ECM US I NG AN I NTEGRATE D S OFTWARE PACKAGE ( L otus Symphony, Vers i o n 2 . 0 ) 4 . 2. 1. App l i cat i o n modu l e s. The L o t u s Symphony app l i cat ion deve l op e d by Pro fe s s o r Mont e i t h current l y con s i s t s o f s i x m o du l e s , e nt it l ed E l e ctricity analys i s G a s Ana lys i s E l e ct ricity I nvent ory G a s I nvent o ry E l e ctricity Consumption and Product i on. 4 . 2. 2. App l i cat i on funct i on s. I t i s not the funct i o n o f t h i s the s i s t o provi de a det ail e d de script i on o f a l l o f the funct i o n s o f the Sympho n y ECM app l ication ; t his wou l d be overly l engthy and l arge ly superfluous t o t he main t opic . The fe ature s o f mo st re levance t o thi s the s i s can be summari sed as fo l l ows ; Mont hly con s ump t io n and Maximum D emand dat a recorded over a three year period is a n a l y s e d , and i s pre s ent e d graphica l ly i n s everal di f ferent ways ( wit h the ob j ect o f e n s uring the b e s t p o s s ib l e comprehen s i on o f t h e p att ern s b y t h e human ( e xp e rt ) u s e r ) . A l imited range o f t a rif f data i s a l s o ent ere d , and u s e d t o a n a l y s e co s t s in s imi l ar manner t o con s umpt i o n . An int eract ive method is p rovide d t o a l l ow the user t o vary the depth o f ( hypothetica l ) l o ad s he dding , and be pre s ented with a graphica l rep re s entatio n o f the corre sponding shed peri ods , the re sultan t MD leve l , and the cash s aving over the current figure . Al l e l e ctricity con suming e qu ipment is recorded in a n " inve n t o ry '' , t ogether with the re s p on s ible D epartment , and the e s t imat e d u t i l is ation fact or . T his dat a i s then an a l ys e d ( including p aret o ana lysis a n d ran k i ng ) , and pre s ented graphica l ly , with the ob j e ct o f e n s uring the comprehe n s i on by the u s e r o f the p a t t ern o f u s ag e on a department a l basis . F i n a l l y , dat a regarding the rat e o f production o f product s may b e e n t e re d , a l l owing the energy u s age to b e corre l a t e d wit h t he pro duction dat a ( regre s s ion a n a l y s is ) . A current prob lem with the s ymphony E CM pack age i s that t h e raw data is he l d in a s omewhat fragme n t e d and redundant form within the modu l e s t hems e lve s , ris k ing dat a i n t e grity prob l em s ..

(38) 35 4.2.3. I nput s and Output s. The princi p l e i nput s requ i re d are ment i oned ab ove ; t he t o t a l qu an t i t y o f dat a i s not exce s s ive l y l arge , and cou l d be e xpect e d t o b e re adi l y ava i l ab l e t o an o rgan i s at i o n . The re ader i s re ferre d to Appe n d i x A for e x amp l e s o f the output s produced by the S ymphony app l i cat i on . The examp l e s documen t e d are cho s e n for t he i r re l eva nce t o the fo l l owing s e ct i o n s of t h i s t he s i s ..

(39) 36 4.3. ENERGY COST MANAGEMENT US ING MULT I P LE S O F T WARE PACKAGE S. The purp o s e o f this s e ct i on i s firs t l y t o con s i der the s o f tware funct i ons whi ch can be brought t o b e ar on this app l i cat ion , s econdly to con s i der the s o ftware package s ( t o o l s ) i n which t he s e funct i o n s can b e found, and fi n a l l y to recommend a s e lect i on o f s o ftware package s t o e xtend and imp rove the E CM funct i on . 4.3.1. A compari s o n o f ECM t a s k s and s o ftware p ack age funct i ons .. I n o rder to i dent i fy t he s o ftware package funct i on s re quire d , it i s nece s s ary to ( re ) e x am i ne both ECM a s a s ub j e ct , and a l s o the a ims of t h i s pro j ect . The former are l i st ed in s ect i on 4 . 1 . 3 , whi l e t he l atter a re found i n sect i on 5 . 1 o f thi s t he s i s . The part icu l ar s o ftware funct i on s thus i dent i fi e d a re ; a/ Me ans o f st oring and retri eving t he raw data b/ Me ans o f pre s ent i ng the dat a , f o l l ow i ng s o rt ing and arithme t i c man ipu l at i o n , s o a s t o a l l ow a human exp ert recogn i s e import ant f e a t ure s / trends . cl Me ans o f aut omat i ca l ly ident i fying and drawing att ent ion t o the s e feature s , p a t t e rn s or trends . d/ Me ans t o a l l ow a u s er t o a d j u st the p at t ern o f e nergy u s age , and obs erve the e f fect upo n overal l co s t . e/ Me ans t o veri fy whether a propo s ed a d j u s tment i s v a l i d or de s i rab l e . 4.3.2. S e l e ct i on o f i ntegrat i on appro ach o perat i o n , dat a ). ( in t e grat i o n o f. 4 . 3 . 2 . 1 I n t e grat ion o f operat i on O n e o f the ma i n fact ors a f fect ing the a s s i gnment o f funct i on s is that the s i z e o f the Symphony and VP Expert p a ckages preclude t he s e being he l d in ( P C ) memory s imu l t ane ou s ly . Th i s dict at e s that the " integra t i on of operat i on " ( s ee sect i on 3 . 4 . 3 ab ove ) needs t o be o f the type i n which the u s e r s e l e ct s one or othe r s o ftware p ackage to be l o aded int o memory , and when f i n i s hed with thi s p a ck age , a l l ows it to b e re l e a s e d from memory pri o r t o l o ading a l t ern a t i ve package s . 4 . 3 . 2 . 2 I nt e grat ion o f dat a I t w a s init i a l ly hoped that " in tegra t i on o f dat a " cou l d b e ach i eved b y having VP Expert acce s s t h e Symphon y spre ads hee t s dire ct l y ; un fortun at e ly t h i s proved i mp o s s ib l e , due t o the s i z e o f s ome o f t he ECM spreads he e t s ( an d t he l e s s import ant fact t hat VP E xpert requ i res spreadshee t s t o u s e the " .WK S " f i l e.

(40) 37 exten s i on ) . I ntegrat i on o f dat a was there f ore achi eved by t he use o f a sma l l i n t e rme di ate s pre adsheet f i l e wh i ch can b e re ad and wri t t e n to b y both VP E xpert and S ymphony . The f i n a l prot otype a l s o re ads and wri t e s dat a t o two dB a s e I I I format dat a f i l e s , ( h o l ding invent o ry dat a , and records of a l l e l ect rica l l o ad movement s propo s ed) . At a l at e r dat e it i s propo s e d t o arrange f o r the inve n t o ry f i l e to be writ t e n to b y the S ymphony app l i cat i o n . Th i s operat i on wi l l re quire s ome care , s i nce a l th ough the structure o f the dat a i s t h e s ame i n t h e dBa s e a n d Symphony f i l e s , the dat a de fi n i t i on i s s l i ght l y d i f ferent ; t he S ymphony f i l e records det a i l s o f " every i t e m o f equ ipme nt whi ch cons ume s e l e ctrical power " , wh i l e the dBa s e f i l e records det a i l s o f " every b l ock o f e l ectrical equ ipment whi ch can be t urne d on or o ff as a uni t " . 4 . 3.3. S e l e ct i on and eva l u at i on o f s o ftware p a c k age s .. C on s i de r i n g the above l i st o f funct i on s , and t he so ftware p a ck age s ava i l ab l e , the fo l l owing obs e rvat i o n s can be made ; A/ The data s t o rage requ i rement s dict a t e e it he r a dedica t e d datab a s e , o r the dat aba s e funct i o n s o f a spre a d s he e t . A con s i derat i on o f the dat a vo l ume s e s t ima t e d i n s e ct ion 5 . 3 . 1 . 1 w i l l s h ow that t he MACH I NE - S LO T dat a vo l ume i s far beyond the cap acit y o f a spre ad s he e t , and the COMPANY-DAY e nt it y i s probab ly appro a c h i n g the pract ica l l imit o f record numbers for a spre a d s h e e t such as Lotus S ymphony . Provide d t hat the deci s i on i s made to not imp l ement t he s e two e n t i t i e s , howev e r , t he vo lume s and record numb ers o f t h e rema i n i ng ent i t i e s do not preclude t he u s e o f a spre a d s h e e t for s t orage . B/ The analys i s o f the numerica l dat a i s n o t comp l e x , e ither i n t e rms o f mathemat ica l fun ct i on s , o r i n t e rms of dat a v o lume s ; thi s funct i o n cou l d be undert aken with appro x imat e ly e qu a l ease by e ither s pre adshee t , dat ab a s e , o r programming l anguage p a ckage s , a n d by expert s ys t em package s with only s l i ght l y more di ffi cu l t y . Cl Wh i l e the dat a ana l y s i s requ i rement s do n o t narrow the cho i ce o f s o ftware package , the comb i n at i o n o f analys i s and re sult pre s entat i o n requ irement s sugge st the u s e o f a spre adsheet . P rovi de d that the d e c i s i o n i s made n o t t o imp l ement the MACH I NE - S LOT , and C OMPANY -DAY ent i t i e s t he dat a st orage vo lume i s within t h e capab i l i t i e s o f t h e spre a d s heet . D/ The data man ipu l at i on aspe ct s pre s e nt a more comp l e x requ i rement ; prop o s e d l o ad movement s may or may not be v a l i d ( i t wou l d obv i ou s ly b e inva l id t o prop o s e moving t h e l o ad o f a n i t em o f e qu ipment whi ch w a s not.

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