fuzzzy app.pdf

8/14/2019 fuzzzy app.pdf

1/13

Appl ication of Fuzzy Logic Concept to Prof itabili ty Quanti ficat ion in Plast icRecycling

S.A. Oke, M.Sc.1*, A.O. Johnson, B.Sc.1, I.O. Popoola, B.Sc.1,O.E. Charles-Owaba, Ph.D.2, and F. A. Oyawale, Ph.D.2

1Department of Mechanical Engineering, University of Lagos, Nigeria2Department of Industrial and Production Engineering, University of Ibadan, Nigeria

* E-mail: [email protected]

ABSTRACT

This paper aims at applying a fuzzy logic controlmodel to profitability in a case study of theplastic recycling industry in Nigeria. The studiesof profitability components of the plasticrecycling industry as used to develop a model

framework and the application of fuzzy logiccontrol model to the framework are given in thispaper. A brief introduction to profitabilityconcepts as well as useful suggestions andconclusions are all integral part of this paperwhich is based on the application of a fuzzy logicmodel of control to profitability concept in plasticrecycling industry.

(Keywords: manufacturing, process analysis,mathematical modelling, profitability, return on

investment, recycling, plastics, polymers, materialreclamation)

INTRODUCTION

The profitability of recycling industries has beenknown to be highly dependent on the effectivemanagement of resources and managementpractices [1, 2, 3, 22, 28]. Taking the plasticrecycling industry as a case study, the recyclingof plastics or polymers has contributed in nosmall measure to the conservation of materialand consequent low cost of production.

The ultimate resultant effect of the recycling

process is high profit generated due to the lowcost of production, hence, the link betweenprofitability and recycling industry [8, 20, 21].Since the ultimate aim of any capitalist industryis to make profit, the profitability concept is ofgreat significance in the engineering industry [9,11, 12, 16]. The profitability concept is thusverified using the plastic of recycling industry inNigeria as a case study.

In the plastic recycling industry in Nigeria,recycling of materials like polyvinylchloride(PVC), polyethylene terephthalate (PET), high-density polyethylene (HDPE), etc., has provenbeneficial to the nations economy. Therecycling process in the plastics industry is

divided into two major parts: 1) the pre-recyclingprocesses; (i) collection, (ii) size reduction (iii)separation or sorting and (iv) cleaning anddrying; and 2) the extrusion process; whichhomogenises the plastic and produces amaterial that is easy-to-work on to produce newproducts.

The major equipment in the extrusion process isthe extruder (e.g. single-screw extruder). Thisconsists of a screw in a metal cylinder (orbarrel). The barrel is surrounded by electricalheater bands and a fan (for melting and cooling).

The screw is connected through a thrust bearingand gearing which drives a motor that rotatesthe screw in the barrel. A conical hopper isconnected to the feed throat and a hole in thebarrel near the drive end of the screw. Theopposite end of the barrel is fully open andexposes the tip of the screw. A die is connectedto the open end of the extruder. The extrusionprocess involves the feeding of solid plasticmaterial into the extruding chamber after beingheated to molten form, and finally extruded in ahomogenous form through the die.

The point of interest in the application of a fuzzylogic model in the profitability concept is how thevarious processes involved in production affectthe cost of production. Since the cost ofproduction, as well as the selling price ofproducts, influence the profit generated by anindustry, both are used in generating a modelusing fuzzy logic, and in applying it to theprofitability concept. The production cost isderived from the cost incurred to recycle the

The Pacific Journal of Science and Technology 163http://www.akamaiuniversity.us/PJST.htm Volume 7. Number 2. November 2006 (Fall)
mailto:[email protected]:[email protected]


2/13

desired quantity of plastic materials as well asother costs of production including salaries,wages, rent, depreciation on machines andequipment, sundry expenses, and so on. Theselling price is arrived at base on the cost ofproduction and the profit generated from therelationship between the aforementionedphenomena (cost of production and sellingprice). Both are used as components of thefuzzy logic model in profitability concept ofplastic recycling industry.

LITERATURE REVIEW

This section provides an overview of selectedresearch on the concepts of recycling, designfor recycling, and life cycle costing. On lifecycle research, a variety of investigations havebeen carried out in the area of logistics,

economics of building, life cycle ofmanufacturing cells, and service organization [4,5, 10, 17, 26]. Although these studies haveestablished the relevance of life cycle analysis inany financial calculation functions such asdiscussed in this paper, very few articles haveconsidered the concept of life cycle as applied toplastic recycling. A close study in this regard iscredited to Larsen [15] who investigated ongarbage life cycle model.

The strength of the work is that the plasticrecycling mathematical functions considered

here reduces to a considerable extent theamounts of raw and natural materials obtainedfrom the earth. This justifies recycling in theplastics industry since preservation of naturalresources is encouraged. The weakness ofplastic recycling lies in the releases of chemicalharmful to the environment. By consideringLarsens work [15], no efforts were made atimplying the profitability of plastic recycling. Thisis a gap that the current work aims to close.

Good support for the plastic recycling modeldiscussed here is found in Goosey and Kellner

[7]. The work is concerned with new legislationto encourage the recycling of life electronics andmoves to implement sustainable development inelectronics manufacturing have focusedattention on the large quantity of printed circuitboards (PCBs) being consigned to landfills.

Also, in a recent investigation conducted onbehalf of the UKs Department of Trade andIndustry, the new methodologies for dealing withend of life circuit boards were identified as a

priority issue. Within the UK it is estimated that

50,000 tonnes per annum of PCB scrap iscurrently generated and investigations indicate

that only 15 percent is subjected to any form ofrecycling, with the remainder consigned tolandfills. This paper reports the results of a

scooping study carried out to identify thetechnologies and processes that can be used torecycle materials from end of life PCBs. Still, thework of Goosey and Kellney [7] has notadequately addressed the issue of plasticrecycling. In particular, the profitability modelproposed here was not mentioned. This justifiesthe need for the current work.

In a practical approach to life cyclemanagement, Price and Coy [19] suggested thatthe scope of a manufacturers environmentalresponsibility increasingly extends beyond thefactory gate to include customer use anddisposal of products. A practical case of 3M lifecycle management (LCM) implementation isdiscussed. The process helps its more than 40operating units meet or exceed such presentand future requirements by achieving twoobjectives: 1) identification of environmental,health and safety (EHS) opportunities andcompetitive market advantages arising fromsuperior performance in these areas; and 2)characterization and management of EHS risksas well as resources and energy use throughouta products life cycle. The process consists ofsix steps leading to a life cycle matrix that

organizes environmental, health and safetyinformation at all phases, from raw materialselection, development (laboratory), andmanufacturing to customer use and disposal ofthe companys products. Although a similarLCM process is used for 3M Laboratories, thefocus of this paper is on business-unitimplementation.

The current authors' deduction from the work ofPrice and Coy [19] is that recycling is used toreduce environmental pollution. Throughrecycling, recycled products are modified, thus

having a wide range of use than in the originalproduct. Another strength of plastic recycling, inparticular, is that it reduces the overallexpenditure in production and it is highlyprofitable. However, the limitation found in Priceand Coy [19] is that no attempt was made tointroduce any financial ratio that relate to theprofitability concept in plastic recycling. This gaphas been identified and treated in the currentwork.



3/13

A plastic recycling investigation was carried outby Gobin and Manos [6]. The catalyticdegradation of polyethylene over variousmicroporous materials (i.e., zeolites, zeolite-based commercial cracking catalysts as well asclays and their pillared analogues) was studiedin a semi-batch reactor. Over all catalysts theliquid products formed had a boiling pointdistribution in the range of motor engine fuels,which increases considerably the viability of themethod as a commercial recycling process.From the zeolites, ZSM-5 resulted mostly ingaseous products and almost no coking due toits shape selectivity properties.

Commercial cracking catalysts fully degradedthe polymer resulting in higher liquid yield andlower coke content than their parent ultra table Yzeolite. This confirmed the suitability of suchcatalysts for a polymer recycling process and its

commercialization potential, as it confirmed thepotential of plastic waste being co-fed into arefinery-cracking unit. Clays, saponite, andZenithN, a montmorillonite, and their pillaredanalogues were less active than zeolites, butcould fully degrade the polymer. They sowedenhanced liquid formation, due to their mildacidity, and lower coke formation. Regeneratedpillared clays offered practically the sameperformance as fresh samples, but their originalclays performance deteriorated after removal ofthe formed coke. Although performance of theregenerated saponite was satisfactory, with the

regenerated zenith the structural damage wasso extensive that plastic was only partlydegraded.

A good strength of the paper is that it highlightsthe recycling process as important in helpingresearch for suitable materials, as well as betterand more efficient for industrial processes. Thisis implied for the study. However, the weaknessof the recycling process in general is the highinitial cost involved in setting up recycling plants.

A great deal of research is needed to ascertainthe best recycling modes for a particular

material. Experimentally, it could be expensive.An opportunity that emerges from this reviewedpaper is the need for some financial functionsthat measure profitability. The current workaddresses this need.

Another study that relates to plastic recycling isfrom Lee et al. [14]. This study analyzed therecycling potential of plastic wastes generatedby health care facilities for this study, the authors

obtained waste streams and recycling data fromfive typical city hospitals and medical centersand three animal hospitals in Massachusetts.The authors analyzed the sources, disposalcosts, and plastic content of medical wastes,and also determined the components, sources,types and amounts of medical plastic wastes.The authors then evaluated the recyclingpotential of plastic wastes produced by generalcity hospitals departments, such as cafeterias,operating rooms, laboratories, emergencyrooms, ambulance service and facilities, andanimal hospitals. Facilities, laboratories,operating rooms, and cafeterias were identifiedas major sources of plastic wastes generated byhospitals. It was determined that the recyclingpotential of plastics generated in hospitalcafeterias was much greater than that in otherdepartments, mainly due to a very slight chanceof contamination or infection and simplification of

purchasing plastic components.

Finally, the authors discuss methods to increasethe recycling of medical plastic wastes. Thisstudy suggests that a classification at wastegeneration sources, depending upon infectionchance and/or plastic component, could be amethod for the improved recycling of plasticwastes in hospitals. The implication of theresearch by Lee at al. [14] is that recyclingcreates economic opportunities. Recyclingcould become a major sector in many economicin the years to come because of its importance

to people and the environment. Recycling isalso a major source of employment andresearch opportunities. Again no consideration isgiven to profitability measures of the plasticrecycling system such as addressed in this work.

A related study on plastic recycling is due toSmith et al. [25]. The study is basically a surveyof a scheme in the United Kingdom to collectplastic bottles for recycling. The authors statedthat the Environment Act imposes a legalrequirement for plastic packaging to be recycled.Recycling of post consumer polyethylene

terephthalate (PET), polyvinylchloride (PVC),and high-density polyethylene (HDPE) bottleswas expected to make a significant contributionto the Environment Acts national target of 15%recycling of plastic of plastic packaging waste by2001. This paper summarizes the finding of anational survey of local authority post-consumerplastic bottle recycling schemes conducted atthe end of 1997, establishing an overview of UKactivity. Areas investigated included the type,



4/13

distribution and efficacy of schemes. Surveyresults are considered in the light of experiencein the UK and abroad.

While plastic bottle recycling has grown rapidlysince 1990, projections based on currentrecycling rates and local authority plans suggestthat further assistance was required for the 2001target to be met. Quite clearly, survey projectsdo not shed light into modelling, but the gap inthe plastic recycling industry relating to thedevelopment of profitability financial functionswas identified by the authors. This is animportant omission that the current workattempts to address.

The environmental effect of reusing andrecycling a plastic-based packaging system wasstudied by Ross and Evans [24]. The studypresents the findings of a lice cycle assessment

(LCA) that examined whether a re-use andrecycle strategy for a plastic-based packagingthat substantially reduces the quantity of wasteto landfill would also reduce the overallenvironmental burden.

The resources and environmental effectsassessed over the life of each of the packagingincluded fossil fuel consumption, greenhousegas emissions, and photochemical oxidantprecursors. The results demonstrate thatrecycle and reuse strategies for plastic-basedproducts can yield significant environmental

benefits. The study also includes someinteresting findings regarding the relativecontributions of transportation and constructionenergy, and the potential benefits of adjustingthe impact assessment results to take intoaccount the spatial variation in the significanceof some environmental effects. The strength ofthis work lies in the analysis of recycling costswith the use of the life cycle cost concept; ahighly valued approach in recycling problemsolving. Unfortunately no efforts were made todiscuss the relationship that life cycle has withprofitability. This is an aspect with great potential

for development. The issue of profitability istherefore justified in the current work.

In a study on recycling, Treloar et al. [27]analyzed the factors influencing wasteminimization and the use of recycled materialsfor the construction of residential buildings. Theycommented that residential building constructionactivities (new builds), negatively impact theenvironment in the form depleting natural

resources, increasing waste production, andcausing pollution. Previous research hadidentified the benefits of preventing or reducingmaterial waste, mainly in terms of the limitedavailable space for waste disposal, andescalating costs associated with landfills, wastemanagement, and disposal and their impact on abuilding companys profitability. There had,however, been little development internationallyon innovative waste management strategiesaimed at reducing the resource requirement ofthe construction process.

The authors contended that embodied energy isa useful indicator of resource value. Using dataprovided by a regional high-volume residentialbuilder in the State of Victoria, Australia, thepaper identified the various types of waste thatwere generated from the construction of a typicalstandard house. It was found that in the

particular case, wasted amounts of materialswere less than those found previously by othersfor cases in capital cities (5-10 percent),suggesting that waste minimization strategieswere successfully being implemented. Cost andembodied energy savings from using materialswith recycled content were potentially morebeneficial in terms of embodied energy andresource depletion than waste minimizationstrategies.

In yet another study, the recycling ofconstruction and demolition wastes in the UK

was investigated by Lawson and colleagues[13]. In England and Wales, the constructionindustry produced 53.5Mt of construction anddemolition waste (C&D waste) annually, of which51 percent went to landfills, 40 percent was usedfor land reclamation, and only 9 percent wascrushed for future use or directly recovered.C&D waste may be contaminated, either throughspillage from industrial processes or contact withcontaminated land. There were no guidelines onhow to classify C&D waste as contaminated oron risk management for contaminated C&Dwaste. Research at the UK Building Research

Establishment and the University of Manchesterhad shown that new taxes were making disposalof C&D waste to landfills uneconomic, that lowgrade land-modelling recycling is increasing,and that disposal on-site is preferred. Samplingspatially of structures before demolition andtemporally of processed C&D waste emergingfrom crushers was enabling sources ofcontamination and excedance of guidelinevalues to be compared with natural background



5/13


6/13

CASE STUDY

Definition o f terms

1. Selling Price (SP): This is the selling priceper item of the quantity recycled.

2. Cost Price (CP): This is the cost price peritem of the quantity recycled. This includesall expenses incurred directly during therecycling processes.

3. Quantity Recycled (QR): The quantityrecycled is determined by the control modelbased on the configuration of thecomponents of the recycling equipment asfollows:

D = Screw diameterH = Channel depth in the metering zone

B = Flow widthW = Channel width parallel to the screw axis

= Helix angle of the screwN = Screw speed in revolutions per second (rps)V = Linear velocity

Thus,

( ) ( ) ( )

( )/itemminVVolumesecinTPeriodx/sminQrateflowVolume

Q3

3

R =

= item

V

T

a12L

WPCosh-

2

DhWNCos 32

where,

T = period between the beginning of recyclingand the expected completion in time.

V = volume that makes each item of the recycledproduct.

4. Profit (X): The profit made is the differencein Selling Price (SP) and Cost Price (CP)

multiplied by the quantity recycled (QR).This is given by:

Profit, X = ( )V

T

a12L

WPCosh-

2

DhWNCosCP-SP

32

Error terms

(SP) (QR) (CP) (QR) = O, Zero Error (Z)(No profit no loss)

(SP) (QR) (CP) (QR) = -, Negative Error (N)(Loss)

(SP) (Q

R) (C

P) (Q

R) = +, Positive Error (P)

(Profit)

Error dot terms

d{(SP)(QR)-(CP)(QR)}/dt = 0, Zero error-dot ( )Z& (No profit no loss over time)

d{(SP)(QR)-(CP)(QR)}/dt = -, Negative error-dot ( )N&

(Loss over time)

d{(SP)(QR)-(CP)(QR)}/dt = +, Positive error-dot( )P&

(Profit over time)

To make the fuzzy model in this profitability

concept more effective, the characteristicfuzziness of the model is utilized, which is highlyadvantageous in effective control of any system.Thus, more error and error-dot terms aregenerated as follows:

More error terms

(SP)(QR)-(CP)(QR) = >>> (-), High negativeerror (HN) (Great Loss)

(SP)(QR)-(CP)(QR) = >>> (+), High positive error(HP) (High Profit)

(SP)(QR)-(CP)(QR) = >>>>>> (-), Very highnegative error (VHN) (Verygreat Loss)

(SP)(QR)-(CP)(QR) = >>>>>> (+), Very highpositive error (VHP) (Veryhigh profit)

(SP)(QR)-(CP)(QR) = >> (+), High positive

error-dot (High profit

.

HP

over time)



7/13


8/13

High Negative (VHN), Very High Positive (VHP),Low Negative (LN) and Low Positive (LP))

INPUT #2:

(Error dot, Positive ( ), Zero ( ), Negative

( ), High Negative , Very High Negative

P& Z&

N&

.HN

( )NHV & , Very High Positive ( )PHV & , LowNegative , High Positive and Low

Positive ).

.

LN

.

HP

.

LP

CONCLUSION:

(Output, No profit no Loss (X), Loss (L), Profit(X), High Loss (HL), High Profit (HX), Very HighLoss (VHL), Very High Profit (VHX), Low Loss(LL) and Low Profit (LX))

INPUT #1: System StatusError: (SP)(QR) (CP)(QR)P = Profit, Z = No profit no loss, N = Loss

INPUT #2: System StatusError dot: d(Error)/dt

P = Profit over time, = No profit no loss over

time, = Loss over time.

Z&

N&

OUTPUT Conclusion and System ResponseOutput H = High, L = Low, VH = Very High

APPLICATION OF PROJECT MANAGEMENTPRINCIPLES

The approach to achieving the objective of thisresearch is the use of a fuzzy logic controlmodel. The fuzzy logic model is used toevaluate the relationship with the parameters

necessary in the profitability concept, which are:selling price, the quantity of solid waste recycled,and cost of recycling the solid waste.

The fuzzy logic command used in this regard isIF, AND, THEN. IF is the relationship betweenselling and cost price of recycled product; ANDis the relationship over time; and THEN is theoutput.

In the course of applying this command to theprofitability in solid waste recycling, the variouscomponents of fuzzy logic model are used, andthey are as follows:

i. LINGUISTIC VARIABLE:(SP)QR (CP)QR

ii. ERROR TERMS:

{(SP)QR (CP)QR}=Positive =Optimistic =Op {(SP)QR (CP)QR} =Negative =Pessimistic =Pe {(SP)QR (CP)QR} =Zero =Most Likely =MLiii. ERROR-DOT TERMS:

d{(SP)QR (CP)QR}/dt = =Optimistic =OP& p d{(SP)QR (CP)QR}/dt = =PN& e

d{(SP)QR (CP)QR}/dt= =MZ& L

From these components of fuzzy logic model, arule matrix, rule structure and system operatingrules are generated for effective control of theprofitability and solid waste recycling system.

Rule Matrix

(Error)

P N Z

1Op

2Pe

3ML

(Error-

dot)

Rule Structure

i. IF {SP)QR (CP)QR} = P, AND d{SP)QR

(CP)QR}/dt = , THEN output = OP& p

ii. IF {SP)QR

(CP)QR

} = N, AND d{SP)QR

(CP)QR}/dt = , THEN output = PN& e

iii. IF {SP)QR (CP)QR} = Z, AND d{SP)QR

(CP)QR}/dt = , THEN output = MZ& L



9/13

System Operating Rules

INPUT # 1:

(Error, Positive (P), Negative (N), Zero

(Z))

INPUT # 2:

(Error-dot, Positive ( ), Negative ( ),

Zero ( ))Zero ( ))

P& N&

Z&

CONCLUSION:CONCLUSION:(Output, Optimistic (Op), Pessimistic (Pe),

Most Likely (ML))

(Output, Optimistic (O

INPUT #1:INPUT #1:

System StatusSystem Status

Error = {SP)QR (CP)QR}Error = {SP)P = Optimistic, N = Pessimistic, Z = Most

Likely

P = Optimistic, N = Pessimistic, Z = Most

Likely

Error-dot = d{SP)QR (CP)QR}/dtError-dot = d{SP)

P& = Getting Optimistic, = Getting

Pessimistic, = Getting Most Likely

= Getting Optimistic, = Getting

Pessimistic, = Getting Most Likely

N&

Z&

OUTPUTOUTPUTConclusion & System ResponseConclusion & System Response

Output Op = Optimistic, Pe = Pessimistic,

ML= Most Likely

Output O

OTHER EXTENSIONS

Z&

P& N&

Z&

p), Pessimistic (Pe),

Most Likely (ML))

QR (CP)QR}

QR (CP)QR}/dt

p = Optimistic, Pe = Pessimistic,

ML= Most Likely

OTHER EXTENSIONSRepresenting the components of the fuzzy logiccontrol model of the profitability concept in solidwaste recycling with membership functions, weobtain Table 1:

Table 1:Components of Fuzzy Logic Model

Level

No.

Interpretation Fuzzy

Output

Linguistic

Variables123

PessimisticMost LikelyOptimistic

NegativeZeroPositive

{(SP)QR (CP)QR}{(SP)QR (CP)QR}{(SP)QR (CP)QR}

where the degree of relationship between fuzzyoutput and membership function ranges from 0 1.0. Illustrating the above table graphically, wehave the following (Figure 2):

denotes positive denotes negative denotes zero

Figure 2:Graph of Fuzzy Logic Control Model

The interpretation of the graph shows that:

i. When the selling price of quantity of solid

waste recycled is more than cost price ofquantity recycled the model promptspositive (optimistic output) 3 ( = 0.9).

ii. When the cost price of quantity of recycledis more than selling price of quantityrecycled the model prompts negative(pessimistic output) 3 ( = 0.9).

iii. When the selling and cost prices of thequantity of solid waste recycled are equalthe model prompts zero (Most Likelyoutput) 2( = 1.0).

Representing the fuzzy logic control modelrelationship by the use of direct graph we have:

X1 X2

X3

0.8

0.5

0.3

OP

N

Figure 2:Showing the Strength of Relationshipswithin the Fuzzy Logic Outputs; Positive, Zero

and Negative.



10/13

Note:X1= PositiveX2= ZeroX3= Negative0.8 = Strong relationship0.5 = Weak relationship0.3 = Weaker relationship

This implies that when the selling price of thequantity of solid waste recycled is higher thanthe cost price, it is difficult to run at loss wherethe cost price is higher (Negative) as indicatedby:

= Weaker relationship

When the selling price of the quantity of solidwaste recycled is equal to the cost price, it isvery easy for the selling price to go lower thanthe cost price of the quantity of solid wasterecycled, thus,

= Stronger relationship

Whereas it is not that easy for the selling pricewhich is equal to the cost price to go higher thanthe cost price, as indicated by:

= Weak relationship

For a more simplified graphical illustration, thefollowing table of membership functions and costlevels is given:

Table 2:Relationships between Cost Level andMembership Function

Membership Cost level Cost %

0 22.5 4.55 8.5

9 1.0

Low costHigh costVery high cost

Maximum cost

0 4041 6061 80

81 100

X1 X3

NP

0.3

Figure 3:Graphical Illustration of Relationshipbetween Cost Level and Membership Function

To define the fuzzy logic model more clearly aterm is used to represent the procedurefollowed. This term is known as defuzzification.X2 X3

NO

0.8

DEFUZZIFICATION

Defuzzification is the term used for theprocedure followed in an attempt to convert thefuzzy set having overall conclusions to a singleconclusion or value. There are various methodsused in defuzzification, the common one beingthe center of gravity of the overall fuzzy setconclusions. If a fuzzy set is represented by Z,defined over the interval (a, b), the center-of-gravity defuzzification c is given by:

X1 X2

OP

0.5

=

b

z(x)dx

xz(x)dxc

a

b

a

Based on this idea of defuzzification, anextension of fuzzy logic model is thought of inlooking into how more specific output can beachieved.



11/13

This leads to further research into neuro-fuzzymodel which intends to combine both fuzzy logicand neural networks.

RECOMMENDATIONS

Effective control of profitability should be givenhigh consideration in future research work, so asto help in maximizing profit, the basic reason forwhich any industries are set up.

It is recommended that software be developed insubsequent research work based on the fuzzylogic model with consideration to a standard thatwill always ensure profit maximization despitevarying costs of production upon which theselling price, and ultimately profit, in an industrydepend. The fuzzy logic model is of greatsignificance in this regard, since the desiredoutcome of an operation can be controlled andensured due to the fuzziness of fuzzy logicwhich accommodates wide variation in inputparameter(s) like production cost.

The fuzzy logic model reveals clearly that loss isincurred in various magnitudes, only when thecost of production is high, compared to theselling price. In the case of the plastic recyclingindustry, the cost of production depends onrecycling process and other processes involvedin production, hence in engineering terms, it isrecommended that the configuration of the

recycling equipment (extruder) which determinesthe quantity of materials recycled should bedesigned so as to reduce the cost of recycling tothe barest minimum.

CONCLUSION

Since the survival of any industrial process isdependent on the profitability concept, and it isclear that the fuzzy logic model is highlyeffectively in controlling profitability to desiredstandard, more research work is encouraged in

the area of application of fuzzy logic toprofitability concept in industries.

REFERENCES

1. Chen, K. 2001. "Development of IntegratedDesign for Disassembly and Recycling inConcurrent Engineering". Journal of IntegratedManufacturing Systems.12(1):67-79.

2. Craighill, A.L. and Powell J.C. 1996. "LifecycleAssessment and Economic Evaluation ofRecycling: A Case Study". Resource,Conservation & Recycling. 17(2):75-96.

3. Cunningham, M.T. 1969. The Application of

Product Life Cycles to Corporate Strategy: SomeResearch Findings. European Journal ofMarketing. 3(1):32-44.

4. El-Haram, M.A., Marenjak, S., and Horner, M.W.2002. Development of a Generic Framework forCollecting Whole Life Cost Data for the BuildingIndustry. Journal of Quality in MaintenanceEngineering. 8(2):144-151.

5. Fernandez, J.A., De Oluveira, R., and Hochheim,N. 2002. Application of Family Life CycleConcept in Determining Potential Segment forHousing Projects: Case Study of Two DowntownProjects in Florianopolis, Brazil. 20(5):312-325.

6. Gobin, K. and Mano, G. 2004. PolymerDegradation to Fuels over Microporous Catalystsas a Tertiary Plastic Recycling Method. PolymerDegradation and Stability. 83(2):267-279.

7. Goosey, M. and Kellner, R. 2003. RecyclingTechnologies for the Treatment of end of lifePrinted Circuit Boards (PCBs). Circuit World.29(3):33-37.

8. Gronostajski, J. and Matuszak, A.A. 1999. TheRecycling of Metals by Plastic Deformation: AnExample of Recycling of Aluminum and its AlloysChips. Journal of Materials Processing

Technology. 92:35-41.

9. Helms, M.M. and Renfrow, T.W. 1994.Expansionary Processes of the Small Business:

A Life Cycle Profile. Management Decision.32(9):43-45.

10. Hutcheson, T.M. 1994. The Life CycleEconomics of Buildings. Facilities. 12(5):11-15.

11. Institute of Scrap Recycling Industries. 2006.Web page. http://www.isri.org

12. Ishii, K., Eubanks, C.F., and Di Marco, P. 1994."Design for Product Retirement and Material Life-Cycle". Materials & Design. 15(4):225-233.

13. Lawson, N., Douglas, I., Garvin S., McGrath, C.,Manning, D., and Vetterlein, J. 2001. "RecyclingConstruction and Demolition Wastes: A UKPerspective". Journal of EnvironmentalManagement and Health. 12(2):146-157.

14. Lee, B.K., Ellenbecker, M.J., and Moure-Eraso,R. 2002. Analyses of the Recycling Potential of



12/13

Medical Plastic Wastes. Waste Management.22(5):461-470.

15. Larsen, B. 2001. The Garbage Can Life CycleModel of Quality Management. The TQMMagazine. 13(2):95-104.

16. Lundquist, L. 2000. Life Cycle Engineering ofPlastics: Technology, Economy and theEnvironment. Elsevier: Oxford, UK.

17. Marsh, R.F., Meredith, J.R., and McCutcheon,D.M., 1997. The Life Cycle of ManufacturingCells. International Journal of Operations andProduction Management. 17(12):1167-1182.

18. Pohlen, T.L. and Farris, M.T. 1992. ReverseLogistics in Plastics Recycling". InternationalJournal of Physical Distribution and LogisticsManagement. 22(7).

19. Price, E.E. and Donald, R.C. 2001. Life Cycle

Management at 3M: A Practical Approach.Environmental Management and Health.12(3):254-259.

20. Recycling Today. 2006. Web page.http://www.recyclingtoday.com.

21. Recycling International. 2006. Web page.http://www.recyclinginternational.com.

22. Reed, R. 1987. Fashion Life Cycles andExtension Theory. European Journal ofMarketing. 21(3):52-62.

23. Romualdo, R.M., Gelmires de Araujo, N., Heber,

C.F., and Helio de lucena, L., 2002. Recycling ofGranite Industry Waste from the NortheastRegion of Brazil". Journal on EnvironmentalManagement and Health. 13:134-141.

24. Ross, S. and Evans, D. 2003. TheEnvironmental Effect of Rusting and Recycling aPlastic-Based Packaging System. Journal ofCleaner Production. 11(5):561-571.

25. Smith, D.N., Harison, L.M., and Simmons, A.J.1999. A Survey of Schemes in the UnitedKingdom Collecting Plastic Bottles for Recycling.Resources, Conservation, and Recycling. 25(1):17-34.

26. Tibben-Lembke, S.R. 2002. Life After Death:Reverse Logistics and the Product Life Cycle.International Journal of Physical Distribution andLogistics Management. 32(3):223-244.

27. Treloar, G.J., Gupta, H., Love, P.E.D. andNguyen, B. 2003. "An Analysis of FactorsInfluencing Waste Minimization and Use ofRecycled Materials for the Construction of

Residential Buildings". International Journal ofManagement of Environmental Quality.14(1):134-145.

28. Zineldin, M. 1996. Bank-Corporate ClientPartnership Relationship: Benefits and LifeCycle. The International Journal of Banking

Marketing. 14(3):14-22.

ABOUT THE AUTHORS

S.A. Oke, M.Sc. graduated in IndustrialEngineering from the University of Ibadan,Nigeria with Bachelor and Master's degrees in1989 and 1992 respectively. He is currently adoctoral candidate at the University of Ibadan,Nigeria. He worked for the IDM Services Limitedas a consultant and currently lectures in theDepartment of Mechanical Engineering,University of Lagos, Nigeria.

A.O Johnson, B.Sc. is a graduate ofMechanical Engineering at the University ofLagos. His interests include modelling problemsin production-oriented organizations.

I.O. Popoola, B.Sc. is a graduate of MechanicalEngineering at the University of Lagos. He iscurrently a graduate student at Louisiana TechUniversity, USA. His interests include modelingproblems in production systems.

O.E. Charles-Owaba, Ph.D. earned his B.S.,

M.S., and Ph.D. degrees in IndustrialEngineering from Texas-Tech University,Lubbock, USA. He has served as Head of theDepartment of Industrial and ProductionEngineering, University of Ibadan, Nigeria. Hehas chaired several conferences and is adistinguished scholar with 6 books and severalinternational and local publications in reputable

journals. He is currently researchingmaintenance scheduling, safety, andperformance measurement. He lectures in theDepartment of Industrial and ProductionEngineering, University of Ibadan.

F.A. Oyawale, Ph.D. earned his B.Sc. andM.Sc. degrees from Western MichiganUniversity, and his Ph.D. from the University ofBenin. He is a Registered Engineer. Currently,he lectures in the Department of Industrial andProduction Engineering, University of Ibadan. Hehas 2 books to his credit and is widely publishedthe scholarly literature.



13/13

SUGGESTED CITATION

Oke, S.A., A.O. Johnson, I.O. Popoola, O.E.Charles-Owaba, and F.A. Oyawale. 2006.Application of Fuzzy Logic Concept toProfitability Quantification in Plastic Recycling.Pacific Journal of Science and Technology.7(2):163-175.

Pacific Journal of Science and Technology


fuzzzy app.pdf

Documents

Transcript of fuzzzy app.pdf