4 Enhance of Ship Safety Based on Maintenance Strategies by Applying of Analytic Hierarchy Process_dagkinis-nikitakos-To-Ventikos-papanikolaou

8/13/2019 4 Enhance of Ship Safety Based on Maintenance Strategies by Applying of Analytic Hierarchy Process_dagkinis-nikitakos-To-Ventikos-papanikolaou

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Enhance of ship safety based on maintenance strategies by applying of Analytic Hierarchy

Process

DAGKINIS IANNIS!" Dr# NIKI$AKS NIKI$AS%

1. University of the Aegean, Dept. of Shipping Trade and Transport, Korai 2a,Chios, 82100, GRCidag!aegean.gr, Te". 22#10$%28&

2. University of the Aegean, Dept. of Shipping Trade and Transport, Korai 2a,Chios, 82100, GRC

nni'!aegean.gr,Te". 22#10$%28&
mailto:[email protected]:[email protected]:[email protected]:[email protected]:[email protected]


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Enhance of ship safety based on maintenance strategies by applying of Analytic Hierarchy

Process

Abstract

The e()ip*ent *aintenan+e strategy is one of the fa+tors inf")en+ing the safety and overa"" operationa"*anage*ent of the ship. Using the rong *aintenan+e strategies +an aste ti*e, *oney, and

reso)r+es, and often has no effe+t on i*proving or *aintaining avai"a-i"ity of e()ip*ents. Th)s the

re"ia-i"ity of the ship is red)+ed, and the ris's and the pro-a-i"ity of fai")res in+reased.

The ai* of this paper is to sho one approa+h to the ris' eva")ation fro* e()ip*ents *aintenan+estrategy of the ship. The paper des+ri-es *ain +hara+teristi+s of aintenan+e Strategies here the

i*pa+t on safety is +r)+ia" and a *ode" for eva")ation of its ris'. The *ode" is -ased on the app"i+ation

of the Ana"yti+ /ierar+hy ro+ess *ethod. The deve"oped *ode" )ses s)-e+tivity, eperien+e and'no"edge, hen deter*ining signifi+an+e of se"e+ted ris' e"e*ents in re"ation to tota" safety and ris'.

Key&ords' aintenan+e Strategy, Ship Safety, )"ti De+ision Criteria a'ing, A/

!# IN$(D)*$IN

The +onstant pro+ess of g"o-a"i3ation "eads the +o*petition a*ong resear+hers and *an)fa+t)rers. As a

res)"t they opti*i3e the -)i"d ()a"ity, and the +ost -e+o*es *ore +o*petitive for the environ*enta"friend"y str)+t)res. 4)rther*ore, the *aority of te+hni+a" and +o**er+ia" a+tivities ithin shipping

ind)stries has -een +ontro""ed +ontin)o)s"y -y the internationa" a)thorities s)+h as 5nternationa"ariti*e 6rgani3ation 756, 5nternationa" Transportation 4ederation 75T4, 5nternationa" 9a-or

6rgani3ation 7596, and other govern*enta" and non:govern*enta" organi3ations 7;G6s "i'e f"agstates, port states, and +ha*-er of shipping, et+. The re"evant organi3ations ens)re the ee+)tion and

i*p"e*entation of internationa" r)"es, reg)"ations, and other re()ire*ents re"ated to the safety and

re"ia-i"ity )nder a )ni()e s+he*e d)ring the vario)s a+tivities in the -o)ndaries of *ariti*etransportation ind)stry. The adoption of stri+t environ*enta" standards, -oth in )rope and in the

United States, is for+ing shipping fir*s to red)+e the e*issions of po"")tants fro* the pro+ess of the

poer prod)+tion p"ants and red)+e the potentia" po"")tion of the operations on ship.

Today ith in+reasing Te+hno"ogy deve"op*ent, the deve"oping of ind)stries a)to*ation and the

in+rease of *a+hinery ()antity, the vo")*e of invest*ent in +o*pany12? -asedon type of ind)stry. ()a""y the in+rease of *a+hinery ()antity on ships and the +o*p"eed Ship

*a+hinery p"an re()ires an opti*a" *aintenan+e po"i+y *i, in order to in+rease the p"an avai"a-i"ityand red)+e the operating +osts. This "eads the shipping -)siness operators a++ording to the inevita-"e

+ost of *aintenan+e, to adopt *aintenan+e strategies on e()ip*ents that are a-"e to +o*p"y ithde*ands on re"ia-i"ity, to in+rease the safety and fina""y at the "oer possi-"e +ost.

A *aintenan+e progra**e *)st -e prod)+ed -ased on operationa" spe+ifi+ needs and o-e+tives,

ta'ing into a++o)nt the -est pra+ti+e. 5t is parti+)"ar"y diffi+)"t to +hoose the -est *i of *aintenan+epo"i+ies on a ship hen needed to +o*p"y ith *any fa+tors. The adoption of previo)s de*ands+reates the need for the operators to se"e+t the -est *aintenan+e po"i+y for ea+h pie+e of e()ip*ent or

syste* fro* a set of possi-"e a"ternatives, for ea*p"e, +orre+tive, preventive, opport)nisti+, +ondition:-ased and predi+tive *aintenan+e po"i+ies hi+h are +onsidered in this paper. This ens)res the

re"ia-i"ity and integrity of the str)+t)re, the syste*s and the e()ip*ents of a vesse", and thro)gheffe+tive *aintenan+e and *anage*ent a+hieves today


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is a +riti+a" and +o*p"e tas' d)e to the great n)*-er of attri-)tes to -e +onsidered, *any of hi+h areintangi-"e.

As an aid to the reso")tion of this pro-"e*, so*e *)"ti:+riteria de+ision *a'ing 7CD approa+hesare proposed in the "iterat)re. A"*eida and @ohoris dis+)ss the app"i+ation of de+ision *a'ing theory

to *aintenan+e ith parti+)"ar attention to *)"ti attri-)te )ti"ity theory >1?. Triantaphy""o) et a".

s)ggests the )se of Ana"yti+a" /ierar+hy ro+ess 7A/ >1$?, +onsidering fo)r *aintenan+e +riteria+ost, repara-i"ity, re"ia-i"ity and avai"a-i"ity. The Re"ia-i"ity Centered aintenan+e 7RC*ethodo"ogy is a te+hni()e hi+h provides a fra*eor' for )ti"i3ing operating eperien+e in a *ore

syste*ati+ ay. RC represents a *ethod for preserving f)n+tiona" integrity and is designed to*ini*i3e *aintenan+e +osts -y -a"an+ing the higher +ost of +orre+tive *aintenan+e against the +ost of

preventive *aintenan+e, ta'ing into a++o)nt >8?. The proposa"s fro* "iterat)re and *any others are+onsidered in design and +onstr)+tion phase for "and -ased ind)stries, air+raft ind)stry and "ater they

adapted to severa" other ind)stries >2?, >#?, >12?.

This paper presents a *ethod -ased on the A/ approa+h : A/ is a de+ision *a'ing te+hni()e, hi+h

ena-"es the *anip)"ation of -oth ()a"itative assess*ents, and ()antitative *etri+s fro* esti*ations orre+orded data in order to i*prove fina" )dg*ents for se"e+tion of *aintenan+e strategy >%? to se"e+t the

*ost appropriate *aintenan+e strategy.

%# +AIN$ENAN*E S$(A$EG,

The @ritish Standards 5nstit)tionB @S$8111# gave a genera""y a++epted approa+h on *aintenan+eand defines it as EA +o*-ination of any a+tions +arried o)t to retain an ite* in or restore it to

a++epta-"e operationa" standardF >?. 5f there is -rea'don, sift a+tions *)st -e ta'en to restore thee()ip*ent or fa+i"ity to its Ea++epta-"e +onditionF. A++epta-"e +onditions i"" in+")de those fa+tors

s)+h as, ffi+ien+y 7f)e" )sage, poer o)tp)t, speed, et+., rod)+tion of good ()a"ity prod)+t servi+e,and Safety of operations.

Hith this definition, it +an -e +"ear"y seen that *aintenan+e invo"ves *ore than Efiing a -ro'ensyste*F. 5t invo"ves the )se of te+hni+a" as e"" as *anage*ent epertise. S)+h *anage*ent epertise

in+")des ngineering 7design and +onstr)+tion, anage*ent 7s+hed)"ing, +ost, infor*ation+o""e+tionana"ysis, and A++o)nting 7profita-i"ity and invest*ent in fa+i"ities.

The a-ove fa+tors ere +onfir*ed -y an investigation +arried o)t -y the United ;ations 5nd)stria"Deve"op*ent 6rgani3ation 7U;5D6 >1?. 5n investigating the possi-i"ity of i*proving )pon*aintenan+e and repair pra+ti+es in deve"oping +o)ntries, a U;5D6 report revea"ed that EThe a+t)a"

*aintenan+e pro-"e* does not "ie on"y in the a+t)a" repair operations -)t a"so in the p"anning and

*anageria" a+tivities at -oth the enterprise and the nationa" "eve"sF.5t is +"ear that a good *aintenan+e progra* *)st define different strategies for different *a+hines.

So*e of these i"" *ain"y affe+t the nor*a" operation of the ship, so*e i"" +on+ern re"evant safetypro-"e*s, and others i"" invo"ve high *aintenan+e +osts. The over"apping of these effe+ts ena-"es )s

to assign a different priority for every ship *a+hinery syste* or +o*ponent, and to +on+entrate thee+ono*i+s and te+hni+a" efforts on areas that +an prod)+e the -est res)"ts.

2.1. Maintenance strategies

The definitions of the *aintenan+e strategies are -ased on re"ia-i"ity data fro* the "iterat)re and on the

te+hni+a" feat)re of the *a+hines. This infor*ation then is )pdated )sing the data a+()ired fro*eperts d)ring the or'ing "ife of the ship e()ip*ents. The ana"ysis syste* has -een str)+t)red in a

rationa" ay so as to 'eep the )pdate pro+ess as o-e+tive as possi-"e. 4)rther*ore, to eva")ate the -este()ip*ents *aintenan+e strategy, d)e to the "arge n)*-er of e()ip*ents that +onsist the ship

operationa" syste* 7p)*ps, +o*pressors, +oo"ers, et+., the ship e()ip*ents syste* is divided intogro)ps ith different +hara+teristi+s. Then, these gro)ps i"" +orrespond to different *aintenan+e

strategies >&?, >#?. The *ain +hara+teristi+s of the gro)ps are the fo""oing

a+hinery gro)p 1. A fai")re in this gro)p +an "ead to serio)s +onse()en+es in ter*s of

or'ers safety, in a syste* of the ship and environ*enta" da*ages, et+. Signifi+ant savings+an -e o-tained -y red)+ing the fai")re fre()en+y and the donti*e "ength. A +aref)"

*aintenan+e 7i.e. 4ied Ti*e aintenan+e or predi+tive +an "ead to good "eve"s of shipIs

+o*pany added:va")e. 5n this +ase, savings in *aintenan+e invest*ents are not advisa-"e.

This gro)p +ontains the +riti+a" e()ip*ent and the -igger per+entage of the ship *a+hines.


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a+hinery gro)p 2. The da*ages derived fro* a fai")re +an -e serio)s -)t, in genera", they

do not affe+t the eterna" environ*ent. A *edi)* +ost red)+tion +an -e o-tained ith an

effe+tive -)t epensive *aintenan+e. 4or this reason Condition @ased *aintenan+e isprefera-"e to a *ore epensive predi+tive po"i+y.

a+hinery gro)p $. The fai")res do not affe+t the ship syste*. The spare parts are not

epensive and, as a +onse()en+e, "o "eve"s of savings +an -e o-tained thro)gh a red)+tion ofspare sto+'s and fai")re fre()en+ies. This gro)p +ontains the "oest per+entage of the*a+hines.

The three a"ternative *aintenan+e strategies hi+h are eva")ated in this st)dy -rief"y are the fo""oing

redi+tive aintenan+e or 4ied S+hed)"ed Ti*e aintenan+e 74T. This is a Ti*e

5nterva" -ased *aintenan+e pra+ti+eB pra+ti+es in this +ategory in+")de sh)t don *aintenan+ehi+h is preJp"anned. 5t10?, >11?. And so on.

Step:-y:step pro+ed)re in )sing A/ is the fo""oing 4irst define de+ision +riteria in the for* of ahierar+hy of o-e+tives. The hierar+hy is str)+t)red on different "eve"s fro* the top 7i.e. the goa"

thro)gh inter*ediate "eve"s 7+riteria and s)-:+riteria on hi+h s)-se()ent "eve"s depend to the "oest"eve" 7i.e. the a"ternatives.

Then eight the +riteria, s)-:+riteria and a"ternatives as a f)n+tion of their i*portan+e for the+orresponding e"e*ent of the higher "eve". 4or this p)rpose, A/ )ses si*p"e pairise +o*parisons to

deter*ine eights and ratings so that the ana"yst +an +on+entrate on )st to fa+tors at one ti*e. 6neof the ()estions hi+h *ight arise hen )sing a pairise +o*parison is ho i*portant is the

E*aintenan+e strategy +ostF fa+tor ith respe+t to the E*aintenan+e strategy app"i+a-i"ityF attri-)te, inter*s of the E*aintenan+e po"i+y se"e+tionF 7i.e. the pro-"e* goa" The anser *ay -e Ee()a""y

i*portantF, Eea'"y *ore i*portantF, et+. The ver-a" responses are then ()antified and trans"ated into

a s+ore via the )se of dis+rete :point s+a"es 7see Ta-"e 1. After a )dg*ent *atri has -eendeve"oped, a priority ve+tor to eight the e"e*ents of the *atri is +a"+)"ated. This is the nor*a"i3ed

eigenve+tor of the *atri.

Sin+e e 'no the priorities of the Criteria ith respe+t to the Goa", and the priorities of theA"ternatives ith respe+t to the Criteria, e +an +a"+)"ate the priorities of the A"ternatives ith respe+t

to the Goa" and fina""y synthesi3e the fina" priorities. This is a straightforard *atter of *)"tip"ying


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and adding, +arried o)t over the ho"e of the hierar+hy and the res)"ts give to )s the overa"" prioritiesand the so")tion for *a'ing the de+ision.

.# $he De/elopment of a Hierarchical Decision +odel

Hhen deve"oping the A/ hierar+hi+a" -oes +hart 74ig. 1, the ai* is to deve"op a genera" fra*eor'

that satisfies the needs of the de+ision *a'ers to so"ve the se"e+tion pro-"e* of the -est *aintenan+estrategy. The str)+t)re has -een +reated -y fo""oing s)ggestions fro* re"evant e()ip*ent

*aintenan+es and or'ing staff of shipping +o*panies. The A/ hierar+hy is deve"oped in this st)dyin three "eve"s. The first "eve" represents the *ain goa" of *aintenan+e se"e+tion and the "oest "eve"

+o*prises the a"ternative *aintenan+e strategies. The eva")ation +riteria that inf")en+e the pri*ary goa"are in+")ded at the se+ond "eve" and are re"ated to fo)r different ris' aspe+ts 6perationa": ndanger at

the 6perationa" Degree, ersonne" Se"e+ting, Ana"ysis of the aintenan+e Re()ire*ents, and Se"e+tingaintenan+e Te+hno"ogy 4ig. 1. These +riteria then +o)"d -rea' don into severa" s)-:+riteria.

The +ir+)*s+ription of the hierar+hy *ethodo"ogy that is des+ri-ed a-ove has -een deve"oped )sing a-rainstor*ing pro+ess >$?. A"so the )dg*ents of a"" the peop"e +on+erned ith *aintenan+e pro-"e*s

in ship and onshore are in+")ded. 5n parti+)"ar, in this st)dy e in+")de the opinions of *aintenan+eengineering personne" 76n Ship and 6ff Ship ho perfor* the *aintenan+e ana"yses and deve"op the

*aintenan+e i*prove*ent pro+ed)res, the operation personne" 7ho *anages the *aintenan+eoperations and the safety personne" 7ho perfor*s the ana"ysis of fa+tor 6perationa" ndanger

Degree.

The re"evant fa+tors defining the 6perationa" ndanger Degree +riterion are identified as "oss of

prop)"sion poer, "oss of e"e+tri+ poer, and fai")res of +argo hand"ing fa+i"ities. These are re"ated tothe operationa" re"ia-i"ity of the ship, the da*age to environ*ent d)e to spi""ing or +o""ision et+, the

inf")en+e to personne" safety, and to the +o*pany


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0# AHP Analysis and (es1lts

The diagra* in fig. 2 shos the A/ hierar+hy at the end of the de+ision *a'ing pro+ess. The goa" is

to +hoose the *ost s)ita-"e *aintenan+e of ()ip*ent aintenan+e Strategies 7S to enhan+e theris' eva")ation -ased on fo)r spe+ifi+ +riteria.

The steering p)*p has -een se"e+ted as a representative *a+hine for the A/ ana"ysis in this st)dy.This p)*p -e"ongs to *a+hinery gro)p 1 hi+h is the gro)p ith -igger per+entage of the ship

*a+hineries. A fai")re in a steering syste* +an "ead to serio)s +onse()en+es in +re safety, shipavai"a-i"ity, and environ*ent. As an overvie, the steering gear on ships provides a *ove*ent of the

r)dder in response to a signa" fro* the -ridge. The tota" syste* +onsists of three parts, +ontro"e()ip*ent, a poer )nit and a trans*ission to the r)dder sto+'. The +ontro" e()ip*ent +onveys a

signa" of desired r)dder ang"e fro* the -ridge and a+tivates the poer )nit and trans*ission syste*)nti" the desired ang"e is rea+hed. The poer )nit provides the for+e, hen re()ired and ith

i**ediate effe+t, to *ove the r)dder to the desired ang"e. Steering gears +an -e arranged ithhydra)"i+ +ontro" e()ip*ent 'non as a Ite"e*eterI, or ith e"e+tri+a" +ontro" e()ip*ent. The poer

)nit *ay in t)rn -e hydra)"i+ or e"e+tri+a""y operated. Us)a""y for seagoing vesse"s the poer )nit ishydra)"i+. /en+e a p)*p is re()ired in the hydra)"i+ syste* hi+h +an i**ediate"y p)*p f")id in

order to provide a hydra)"i+ for+e that i"" *ove the r)dder. 5nstant response does not a""o ti*e for

the p)*p to -e sit+hed on and therefore a +onstant"y r)nning p)*p is re()ired that i"" provide f")idon"y hen re()ired. 4or this reason the p)*ps hi+h are insta""ed ith these feat)res are the varia-"ede"ivery p)*ps.

6n+e the hierar+hy str)+t)re of the *aintenan+e strategy de+ision *a'ing pro-"e* is defined everyavai"a-"e data is i*ported. Then the ana"yti+ hierar+hy pro+ess 7A/ *athe*ati+a" so"ver r)ns to

synthesi3e the res)"ts and nor*a"i3e the va")es. The priorities for the a"ternatives are spe+ified inrespe+t to ea+h of the de+ision +riteria, and priorities for ea+h of the +riteria ith respe+t to their

i*portan+e in rea+hing the goa" are +a"+)"ated )sing pairise +o*parisons. The +o*parisons of

a"ternatives ith respe+t to ndanger of 6perationa" Degree given -y the eperts< )dg*ents are shonin Ta-"e 2. Then they are pro+essed thro)gh the A/ *atri and the priorities res)"ts are shon in

Ta-"e $.

The net steps are the pairs< +o*parison of a"ternatives ith respe+t to ersonne" Se"e+ting, Ana"ysis ofthe aintenan+e Re()ire*ents and Se"e+ting aintenan+e Te+hno"ogy. The eights are transferredinto the *atries and so"ve the A/. Then the +riteria are +o*pared ith respe+t to rea+hing the goa"

and ith pairise +o*parisons, the higher ran'ing +riterion is the one )sed to a+hieve the goa".

Ta-"e . shos the fina" ran'ing for the Steering Gear )*p. @ased on the epertIs +hoi+e of de+ision+riteria, on their )dg*ents a-o)t the re"ative i*portan+e of ea+h, and on their )dg*ents a-o)t

*aintenan+e strategy ith respe+t to ea+h of the +riteria, redi+tive, ith a priority of 0.%1, is -y far

the *ost prefera-"e *aintenan+e strategy. reventive *aintenan+e strategy, ith a priority of 0,2820, is

se+ond, and Corre+tive *aintenan+e strategy, at 0,2%88, is third. 4or the Steering )*p the predi+tivestrategy is high"y prefera-"e ith respe+t to the others -e+a)se a fai")re has +riti+a" inf")en+e to the

ship


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4)rther*ore, +onsidering that the responsi-"e *aintenan+e person +an never -e s)re of the re"ativei*portan+e of de+ision *a'ing in the se"e+tion +riteria hen dea"ing the +o*p"e pro-"e* of a ship

*aintenan+e, the i*prove*ent of effe+tiveness of A/ *ethodo"ogy +o)"d -e a+hieved -yi*p"e*entation of sensitivity ana"ysis for *ore a++)rate res)"ts.

$ables and 2ig1res

Ta-"e 1. 4)nda*enta" S+a"e of A-so")te ;)*-ers

5ntensity of

i*portan+eLa")e des+ription p"anation

1Criterion i and +riterion are of

e()a" i*portan+e.

To a+tivities +ontri-)te e()a""y to the

o-e+tive.

$Criterion i is ea'"y *ore

i*portant than +riterion .

perien+e and )dg*ent s"ight"y favor one

a+tivity over another

%Criterion i is strong"y *ore


perien+e and )dg*ent strong"y favor one

a+tivity over another.

#Criterion i is very strong"y *ore


An a+tivity is strong"y favored and its

do*inan+e de*onstrated in pra+ti+e.

Criterion i is a-so")te"y *orei*portant than +riterion .

The eviden+e favoring one a+tivity over anotheris of the highest possi-"e order of affir*ation.

2,,&,85nter*ediate va")es -eteen the

to ada+ent va")es.Hhen a +o*pro*ise in )dg*ent is needed.

Ta-"e 2. A"ternatives +o*pared ith respe+t to ndanger of 6perationa" Degree.

redi+tive reventive 1 redi+tive is ea'"y *ore i*portant than +riterion to

reventive aintenan+e. Height

redi+tive Corre+tive 1 redi+tive is a-so")te"y *ore i*portant to Corre+tive

aintenan+e. Height

reventive # Corre+tive 1 reventive is very strong"y *ore i*portant to

Corre+tive aintenan+e. Height #

Ta-"e $. The transfer of eights to the *atri.

6perationa" ndanger of

6perationa" Degree

redi+tive reventive Corre+tive riority

redi+tive 1 0,&$

reventive 1 1 # 0,2%$$

Corre+tive 1 1# 1 0,0%28

Ta-"e . The res)"ts for +hoose the -est a"ternative.

riority ith Respe+t to

aintenan+e

strategy

Ris' to

ndanger the6perationa"

Degree

Ris' fro*

ersonne"Se"e+tion

Ris' fro*

Ana"ysis ofaintenan+e

Re()ire*ents

Ris' fro*

Se"e+ting ofaintenan+e

Te+hno"ogy

G6A9

redi+tive 0,$& 0,0121 0,012% 0,0$ 0,%1

reventive 0,1% 0,0281 0,021 0,0#0 0,2820

Corre+tive 0,0$0 0,108 0,112 0,00&& 0,2%88

Tota"s 0,%#% 0,11 0,1%% 0,120% 1,0000


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Figure 1.The A/ Goa", Criteria and A"ternatives.

4ig)re 2. The A/ deve"op*ent and the g"o-a" priority indi+es.

(eferences

>1? A"*eida AT, @ohoris GA. 71%. De+ision theory in *aintenan+e de+ision *a'ing. Mo)rna"

of N)a"ity in aintenan+e ngineering, Lo". 1 5ss 1, pp.$ : %.>2? @asi* A":;aara, 5*ad A"syo)f-. 7200$. Se"e+ting the *ost effi+ient *aintenan+e approa+h

)sing f)33y *)"tip"e +riteria de+ision *a'ing. 5nternationa" Mo)rna" of rod)+tion +ono*i+sLo")*e 8, 5ss)e 1, 11, pp:8%J100.

>$? @evi"a+()a, . and @rag"ia, . 72000. The ana"yti+ hierar+hy pro+ess app"ied to *aintenan+estrategy se"e+tion. Re"ia-. ng. Syst. Saf., #0 pp:#1:8$.

>? @ritish Standards 5nstit)tion. 71# EG"ossary of aintenan+e Ter*s in Terote+hno"ogyF.@S$811. @ritish Standards 5nstit)tion 9ondon, UK.

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