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Chung, Jae Hyun. "Lot size scheduling problem with two level setup cost/time structure." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/25591.
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Xiao, Wen Qiang. "Essays on scheduling and lot sizing models /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?IEEM%202002%20XIAO.
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Chan, Lap-mui Ann. "Near optimal lot-sizing policies for multi-stage production/inventory systems /." [Hong Kong : University of Hong Kong], 1990. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12626533.
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Liu, Xin. "Heuristic strategies for the single-item lot-sizing problem with convex variable production cost." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B3642917X.
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Brandolini, Yara. "Strategie per la gestione integrata delle scorte nella catena logistica: joint economic lot size e consignment stock." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amslaurea.unibo.it/882/.
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Andere-Rendon, Jose 1963. "Economic lot size determination in finite production rate multi-stage assembly systems under power-of-two policies." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277278.
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In this thesis, we consider determining the economic lot sizes for a finite production rate assembly system with n facilities. Costs at each facility consist of a stationary positive echelon holding cost, and a fixed set up cost. The goal is to determine the production lot size at each facility in order to minimize the long-run total average cost of the system. Power-of-two policies, in which the lot size at each facility is a power of two times some base lot size, are considered. A 94%-effective power-of-two policy is determined from the optimal solution to a continuous relaxation problem by an O(n) algorithm, while a 98%-effective power-of-two policy is found using an O(n log n) algorithm. Near optimal solutions to the continuous relaxation problem are found by a subgradient optimization procedure and a cyclic coordinate descent method. Computational results suggest both methods are efficient for very large systems.
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Liu, Xin, and 劉忻. "Heuristic strategies for the single-item lot-sizing problem with convex variable production cost." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B3642917X.
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Quadt, Daniel. "Lot-sizing and scheduling for flexible flow lines /." Berlin : Springer, 2004. http://www.loc.gov/catdir/toc/fy0602/2004109270.html.
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陳立梅 and Lap-mui Ann Chan. "Near optimal lot-sizing policies for multi-stage production/inventory systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31209129.
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Choi, Soodong. "Material flow system integration in EOQ, ELSP, and Kanban production environments /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9901227.
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Hedlund, Tommy, and Daniel Kvarnlöf. "Optimering och balansering av cyklisk produktion : En studie på Sandvik Materials Technology PU Borrstål." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-21350.
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Aim: The purpose of this study is to present and test an algorithm that gives acceptable solutions in the optimization of a dedicated production line consisting of several machines, with regards of inventory holding cost and available capacity. The aim is also to suggest possible improvements in the practical case that has been used to test the model, which have been made in cooperation with Sandvik Materials Technology and it’s product unit Rock Drill Steel, located in Sandviken, Sweden. Method: An algorithm has been elaborated from articles and science reports and has then been tested with data from the practical case. The result has then been evaluated through an analysis where the algorithm’s ability to acceptable solutions and show potential savings with regards to capital tied up in stock of finished products, safety stock and products in work in process. Results and conclusions: The study shows that the algorithm has the ability to create acceptable solutions when given a specific demand rate, cycle time and capacity. The study also shows potential savings when using a shorter production cycle, given that the unit works in a structured way in order to shorten the production cycle. Suggestions for future research: The algorithm tested in this study needs more evaluations regarding its limits and possible benefits through practical and theoretical case studies. Contributions: The algorithm the possibility to combine principles and models aimed at solving the ELSP (Economic Lot Schedule Problem) and the principles of Schedule Leveling, which is a common term in lean production to a model that optimize inventory holding costs. These theories have similar approaches to cyclic production, but have different aims. Key words: cyclic scheduling, ELSP, economic lot size problem, schedule leveling, heijunka, lean productionTitel: Optimering och balansering av cyklisk produktion - en studie på Sandvik Materials Technology PU Borrstål Nivå: C-uppsats i ämnet Industriell Ekonomi Författare: Tommy Hedlund, Daniel Kvarnlöf Handledare: Mohammad Abid Datum: 2016 - Mars Syfte: Studiens syfte är att presentera och testa en algoritm som ger godkända resultat vid optimering av en dedikerad produktionslina bestående av flera produktionsresurser, med avseende på lagerhållningskostnad i omsättningslager samt tillgänglig kapacitet, samt att presentera möjliga förbättringsförslag utifrån de resultat som ges i det praktiska fall som simuleringsmodellen utvärderas genom. Det praktiska fallet i denna studie är Sandvik Materials Technology och dess produktenhet Borrstål. Metod: Studien har genomförts genom att en algoritm har tagits fram utifrån artiklar och forskningsrapporter på området, som sedan har prövats mot studiens praktiska fall. Resultatet har sedan utvärderats genom en analys av algoritmens förmåga att ge godkända lösningar, samt möjlig besparingspotential i det aktuella fallet utifrån kapitalbindning i omsättningslager, säkerhetslager och produkter i arbete. Resultat & slutsats: Studien visar att algoritmen har en god förmåga att skapa godkända resultat utifrån en specifik efterfrågan, cykeltid och kapacitet. Studien visar även på stora potentiella besparingar i kapitalbindning till följd av kortare cykeltid i såväl omsättningslager, säkerhetslager och produkter i arbete, givet att produktenheten arbetar strukturerat med att söka minska cykeltiden. Förslag till fortsatt forskning: Algoritmen behöver ytterligare forskning kring dess begränsningar genom att utvärderas utifrån fler praktiska och teoretiska fall. Uppsatsens bidrag: Algoritmen visar på en möjlighet att kombinera ELSP (economic lot scheduling problem) och dess modeller med de principer som återfinns inom Schedule Leveling, som är ett vanligt begrepp inom lean production. Dessa teorier liknar varandra men har till viss del skilda syften, vilka kan kombineras till en modell som optimerar produktionen med avseende på lagerhållningskostnaderna.
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Moran, Terrence J. "A Simulation and Evaluation Study of the Economic Production Quantity Lot Size and Kanban for a Single Line, Multi-Product Production System Under Various Setup Times." Kent State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=kent1213302997.
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Sridhar, H. K. "Influence of Lot Sizing on Lead Time Error Costs in M.R.P. Systems- a Computer Simulation Study." Thesis, Indian Institute of Science, 1988. http://hdl.handle.net/2005/85.
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Timing of ordering of inventory items is of very great importance in Materials Requirement Planning. Uncertainties in timing can have an adverse effect on the system performance. Most often the lead time variation contribute to timing uncertainties; and their effects are reflected in added costs.
Lead time error effects are investigated in this thesis. The study attempts to estimate the effects through some relevant costs, and their variations across the lot sizing rules.
The hypotheses for this study are 1) Between any two lot sizing rules, there will be a significant difference in error coats due to combined effect of purchased lead time error and manufacturing lead time errors; 2) Relative cost performance of lot sizing rules in MRP is influenced by the lead time errors; 3) There will be a difference in error cost between lot for l o t rule and least total cost rule even with single source of lead time variation.
To carry out the study a MRP programme was developed, in FORTRAN 77 with provisions to include the lot sizing rules while exploding the structure. The lot sizing rules used in the study are Lot for Lot, Silver and Meal heuristics, Wagner-Whitin algorithm, Least total cost, Least unit cost and Part Period balancing.
A simulation model is developed using GPSS/PC, to test the hypotheses. An hypothetical production situation with three end items, each with a different product structure is designed. In addition, a master production schedule and a job shop are also structured. Appropriate distributions are assumed for both manufacturing lead times and purchase lead times. These provide the stochastic variables in the simulation experiments.
A series of experiments were carried out with the model to investigate into the variations of costs amongst lot sizing rules. Results of the simulation experiments prove that there are costs associated with lead time errors in MRP. These error costs vary significantly with different lot sizing rules.
It is also found that the resultant error costs vary significantly even with a single source of lead time variation. Least unit cost rule gives the beat performance having least error costs. Lot for Lot rule has shown the worst performance amongst the lot sizing rules considered. Other interesting results have emerged out of the study.
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Liorentienė, Kristina. "Parama smulkiems ūkiams ir jos tobulinimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050527_112114-42029.
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Research object – the support measures for small farms. Research aim – to identify the support measures for small farms and to suggest their possible ways of improvement. Objectives: 1) To propose the criterions of size of farm and the conception of small farm at policy; 2) To explore the estimations of national economic and social support at economic literature; 3) To explore the national measures for small farms and to deduce the possibility of small farms to use them; 4) To explore the measures of Europe Union for small farms and to deduce the possibility of small farms to use them; 5) To identify the support measures for small farms; 6) To give suggestions for improvement of support measures for small farms. Research methods. To propose the mostly used criterions of size of farms, the conception of small farm at policy and the national economic and social support measures at economic literature were used the analysis and synthesis methods of scientific and juristically literature. To explore the measures of national and of Europe Union supports were used analysis and synthesis methods of juristically literature, programs. To identify the support measures for small farms and to give suggestions were used statistical, comparative analysis and graphic figure methods.
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Bartuškaitė, Aušra. "Valstybės paramos priemonių smulkiam ir vidutiniam verslui įgyvendinimas Lietuvoje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2007. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20070126_084535-91884.
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Mažos ir vidutinės įmonės – dinamiškiausia, nuolat besikeičianti įmonių grupė, vidurinioji ūkio sandaros grandis, turinti lemiamą įtaką ekonominiam augimui ir socialinių santykių stabilumui. Mažos ir vidutinės įmonės (toliau - MVĮ) sudaro gausiausią Lietuvos įmonių grupę, todėl jų skatinimas kurtis, veikti ir plėtotis tampa prioritetine Lietuvos ekonomikos plėtros kryptimi. Lietuvos valdžia įvairiais būdais stengiasi remti MVĮ, kad šios galėtų vystyti savo veiklą bei numato vis daugiau paramos priemonių. Pagrindinis darbo tikslas - išanalizuoti valstybės paramos smulkiam ir vidutiniam verslui įgyvendinimo sistemą Lietuvoje bei pateikti tobulinimosi kryptis. Darbe analizuojama smulkaus ir vidutinio verslo rėmimo politika vykdoma Europos Sąjungoje, kurios pagrindu bus pateikiamos tobulinimosi gairės valstybės paramos SVV teikimui Lietuvoje.Small and medium sized business is the middle structure link of national economy, which has decisive impact to the economy development and social relation stability. Small and medium sized enterprises (further – SME) are amount the biggest part of all Lithuanian enterprises. Thus, governments promotion is requested for business enterprises. Yearly Lithuanian government take about SME and sets supports forms in national market. Thus this becomes the economy development priority in Lithuania. The government, according to instruments of support for SME, attempts to engage people to take part actively in the small and medium business. The main purpose of this work is describing and studying the instruments of government supports for SME and to reveal, which instrument of existing national supports system should be further developed as well as possible to propose ways, how they can be achieved hereafter. Also there are discussed about the main directions of businnes stimulations, which are used in European Union countries and which may be used in Lithuania. It is necessary to mention governments promotion for SME forms, like the creation of business infrastructure net, the establishment of business incubators, tax concessions, municipalities support and etc. Goverment is responsible for financial and non-financial support. It gives the support according to small and medium business programs. The promotion of government for SME could raise not only the development of the... [to full text]
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Bučytė, Jurgita. "Alternatyviosios vertybinių popierių rinkos Lietuvoje veiklos prielaidų vertinimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080818_105425-44366.
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Alternatyvioji vertybinių popierių rinka yra aktualus ekonominių – finansinių studijų objektas, ypač besivystančių finansų rinkų kontekste. Šio baigiamojo darbo tikslas yra atlikus teorinę AVPR analizę bei atsižvelgus į jau veikiančių jų patirtį, įvertinti AVPR Lietuvoje veiklos prielaidas, jas įtakojančių aplinkos veiksnių ir potencialių šioje rinkoje kotiruotis įmonių atžvilgiais. Pirmojoje darbo dalyje atskleidžiami AVPR teoriniai aspektai, antrojoje – atliekamas AVPR veiklos prielaidų vertinimas Lietuvoje bei pristatoma jų tyrimo metodologija. Paskutinė darbo dalis skirta metodologiškai pagrįstam Lietuvos įmonių struktūros projektui pateikti ir kitiems sėkmės veiksniams, t.y. kaip AVPR - First North Lietuvoje veiklos prielaidoms, įvertinti. Taip pat suformuluojamos išvados ir rekomendacijos. Apibendrinant rezultatus galima teigti, jog įmonių veiklos rūšys, siekiant optimaliai diversifikuotos AVPR pagal du nagrinėtus scenarijus yra: transportas, maisto ir gėrimų pramonė, informacijos ir ryšių technologijos bendrovės, kelionių organizavimas ir agentavimas. Pagrindinės AVPR šalyje sėkmingos veiklos prielaidos yra perspektyvių įmonių pritraukimas, diversifikuota AVPR įmonių struktūra, investuotojų pritraukimas, tinkamas reguliavimas, sertifikuotų patarėjų vaidmuo.Alternative market is a relevant subject of economic and financial research., especially in the context of emerging financial markets. The objective of the final paper is to evaluate practice assumptions of alternative market, in respect of environmental influences and enterprises that may be potencial for quoting in the market. In the first part of the paper the theoretical aspects are revealed, and in the second the evaluation of practice assumptions, including good case practices, of alternative market as well as the methodology of research are provided. In the last part the project of Lithuanian enterprises‘ structure in First North is presented and good practices assumptions need to be evaluated. Summing up the results of the research the diversified enterprises‘ structure in respect of the number and variety of sectors according to two scenarios included industrial transportation, food and beverages, information technologies, travel agencies may be constructed. Then recommendations are provided.
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Mazurkevičius, Arūnas. "Įmonių finansų analizės galimybių naudojantis apskaitos informacine sistema vertinimas." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140617_121842-19740.
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Tyrimo objektas – apskaitos informacinės sistemos funkcinės galimybės įmonių finansinei analizei atlikti.
Tyrimo tikslas – parinkti, adaptuoti ir išbandyti modelį, kuriuo naudojantis būtų galima nustatyti apskaitos informacinės sistemos funkcines galimybes mažų ir vidutinių įmonių veiklos finansinei analizei atlikti.
Tyrimo uždaviniai:
1. Išanalizuoti ir apibendrinti mažų ir vidutinių įmonių finansų analizei naudojamus rodiklius bei išskirti pagrindines šių įmonių finansų analizės kryptis ir nustatyti AIS Debetas galimybes sukaupti finansų analizei atlikti reikiamus duomenis.
2. Išanalizuoti ir apibendrinti informacinių sistemų funkcionavimo sėkmę įtakojančius veiksnius, vertinimo kriterijus ir metodus, kuriais naudojantis būtų galima įvertinti šių sistemų funkcionalumą mažose ir vidutinėse įmonėse.
3. Adaptuoti integralų pajėgumų brandos modelį (toliau – CMMI) apskaitos informacinės sistemos funkcionalumui tirti, naudojant adaptuotąjį modelį įvertinti AIS Debetas funkcines galimybes finansų analizei atlikti, pasiūlyti šios programinės įrangos tobulinimo būdus bei įvertinti jų priimtinumą mažoms ir vidutinėms įmonėms.
Tyrimo metodai. Sprendžiant pirmąjį ir antrąjį tyrimo uždavinius buvo naudojami monografinis, palyginimo, loginės analizės ir apibendrinimo bei grafinio vaizdavimo tyrimo metodai. Sprendžiant trečiąjį tyrimo uždavinį buvo naudojamas anketinės ir interviu apklausos, statistinio duomenų apdorojimo, duomenų analizės ir sisteminimo, CMMI ir ISO/IEC 14598... [toliau žr. visą tekstą]Research object: the ability of accounting information system to provide enterprises’ financial analysis. Research aim: to provide search, adoption and testing of the model, allowing assessment of the functional abilities of accounting information system to conduct financial analysis in small and medium size enterprises. Objectives: 1. To provide analysis and summarising of indicators, used for financial analysis and main directions of financial analysis in small and medium-sized enterprises and to investigate in abilities of current version of AIS Debetas to collect necessary data for provision of financial analysis. 2. To provide analysis and summarising of the aspects, influencing quality of functioning of accounting information system, the quality assessment criteria and applicable quality assessment methods used for financial analysis in small and medium-sized enterprises. 3. To provide adaptation of the Capability maturity Model Integration (CMMI) for accounting information system quality evaluation, AIS Debetas quality assessment using adopted model, to propose the ways for software and to evaluate acceptability of proposed improvements for end users in small and medium-sized enterprises. Research methods: monographic, comparison, logical analysis and synthesis, questionnaire and interview surveys, statistical data processing, data analysis and summarising, model of CMMI and ISO/IEC 14598. Research results. The first part of this work presents results of analysis of... [to full text]
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Daberkow, Kevin S. "Financing Ohio’s Public Schools through the Ohio Lottery: Quantitative and Qualitative Dimensions of the Lottery’s Tax Incidence." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1335201752.
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Saňáková, Miroslava. "Řízení stavební zakázky." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409903.
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This diploma thesis solves problems of construction orders management. The key to successful business and stable position in a competitive market is the way of planning, managing and quality processing of construction orders. The aim of this diploma thesis is to describe and analyze the management of a construction order in a selected company, in my case ARCHATT, s.r.o. I also deal with this in this work, namely for the specific order Oprava Severního parkánu a hradeb of Prague Castle. The content of the work is a processed documentation of the supplier's preparation for this order and a detailed description of the entry of construction workers to this daily guarded building.
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Yuan, Chih Hsien, and 袁志賢. "Location-routing Problem Taking Joint Economic Lot Size into Consideration." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/41113976428575464277.
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碩士長庚大學
工商管理學系
98
We study some distribution network design problems, which combine location routing problem (LRP) and joint economic lot size (JELS). In order to minimize the total system cost, we decided facilities' number, location, scope of services, vehicle routing and inventory control simultaneously to satisfy customers’ demand. In this study, we consider inventory holding cost and ordering cost to decide the optimal order quantity for the distribution center. Since finding the optimal solution for this problem is an NP-hard problem, we use genetic algorithms to solve the problem. The results show that if solving the LRP without inventory-related cost being considered, it may cause results to bias and the total cost of systems is larger than solving the LRP and JELS simultaneously.
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Chen, Yu-wen, and 陳俞妏. "Economic Production Lot Size-Reorder Point Inventory Model with Fuzzy Demands." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/38291310176437040354.
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碩士國立中正大學
企業管理所
97
Fuzzy inventory problems are often encountered such that they have discussed widely by several scholars. This paper investigates the economics production lot size-reorder point inventory problem with fuzzy demands being fuzzy numbers. The fuzzy demands in this model is presented by the cuts of fuzzy demands and then the fuzzy total inventory cost for finding inventory policy of (Q,L), where Q is the order quantity and L is the reorder point, is constructed. Five cases are discussed depending on different range of L. Then Yager’s ranking index is adopted to find the optimal Q* and L* with minimum index of fuzzy total cost. Moreover, when the fuzzy demand is a trapezoidal fuzzy number, we can derive the closed-form for the global optimal solutions to Q* and L*. Finally, a numerical example is investigated to illustrate the validity of this model. The method proposed in this paper is helpful for decision makers to control inventory problems effectively in fuzzy environments.
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"A comparison of some lot-sizing heuristic rules independent of EOQ-assumptions." Chinese University of Hong Kong, 1986. http://library.cuhk.edu.hk/record=b5885622.
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楊志德. "An economic production lot size inventory model for deteriorating items with price-dependent." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/57723494266923096131.
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碩士淡江大學
管理科學學系
90
Perishability is a common phenomenon in the inventory systems. The sellers usually keep fewer capacities so that it causes the stock shortage easily. When the shortages occur, some customers are willing to wait for backorder and others would turn to buy from other sellers. At this time, it will bring the loss of sales for sellers. Manufacturing and selling products simultaneously is called the economic production lot size model (EPLS model) in the inventory model. In the traditional EPLS model, it is often assumed that the demand and production rate are constants. In practice, demand rate always varies linearly with price. In the other hand, the production rate may be influenced by the on-hand inventory or the demand. In this study, inventory models are developed for deteriorating items with price-dependent demand rate and partial backordering, in which the rate of deterioration is assumed to be constant. In addition, the shortages are partial backordering, and assuming the backordering rate to be constant. Our purpose is to determinate the different time period of the inventory cycle and the selling price of product that maximize net selling revenue in order to provide the decision-maker to make production cycle and pricing strategy. In Chapter 2, we first develop an EPLS model for deteriorating items with the constant production rate, price-dependent demand rate and partial backordering. In Chapter 3, we consider an EPLS model for deteriorating items with inventory-level-dependent production rate, price-dependent demand rate and partial backordering. In Chapter 4, we present an EPLS model for deteriorating items with demand-dependent production rate, price-dependent demand rate and partial backordering. The optimal solution procedures for the present problems are provided. Numerical examples are added to illustrate the results, and the sensitivity analysis of the optimal solution with respect to parameters of the systems is also carried out for understanding how parameters changes influence the optimal solution.
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Chiu, Sin-ga W., and 王聖嘉. "Optimal Lot-Size Decision for Economic Production Quantity Model with Defective Items Rework." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/xvd6nt.
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博士中原大學
工業工程研究所
92
This research considers optimal lot-size decision for Economic Production Quantity Model (EPQ) with defective items rework. The assumption of perfect quality production condition of the classical EPQ model is unrealistic. Due to process deterioration or other factors, the generation of defective items is inevitable. This study assumes that the defective rate is a random variable and all items produced are inspected. The imperfect quality items can fall into two groups, the repairable and the scrap. The reworking of the repairable defective items starts when the regular production process finishes in each cycle. The rework process is assumed to be imperfect, a random portion of reworked items fail and become scrap. Five specific situations of EPQ model are examined in this research. They are situations where: (1) all defective items are scrap; (2) all defective items are reworked and can be repaired with an additional holding and reworking cost; (3) situation where the defective items fall into two groups, one is scrap and the other is repairable; (4) all defective items are reworked, however, a portion of them fail the reworking and become scrap; (5) An imperfect EPQ model combining the situations described by (3) and (4) above. Mathematical models are developed for each of the aforementioned situations, respectively. Disposal cost per scrap item and repairing and holding cost for each reworked item are included in the cost analysis. The renewal reward theorem is utilized in the proposed mathematical modeling to cope with the variable cycle length. The optimal lot size that minimizes the expected overall costs is derived for each model, where shortages are not permitted. Numerical examples are provided demonstrate the ready and practical usages of our resulting models to the real-life manufacturing firms.
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"On the single level capacitated lot sizing problem." 1998. http://library.cuhk.edu.hk/record=b5889649.
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Yip Ka-yun.Thesis (M.Phil.)--Chinese University of Hong Kong, 1998.
Includes bibliographical references (leaves 107-113).
Abstract also in Chinese.
Chapter Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Overview --- p.1
Chapter 1.2 --- Our Contributions --- p.2
Chapter 1.3 --- Organization of the Thesis --- p.4
Chapter Chapter 2 --- Literature Review --- p.5
Chapter 2.1 --- Overview --- p.5
Chapter 2.2 --- Research in Capacitated Lot Sizing Problem without significant setup times --- p.5
Chapter 2.3 --- Research in Capacitated Lot Sizing Problem with setup time consideration --- p.12
Chapter 2.4 --- Summary --- p.15
Chapter Chapter 3 --- Capacitated Lot Sizing Problem with Setup Times --- p.16
Chapter 3.1 --- Overview --- p.16
Chapter 3.2 --- Problem Description and Formulation --- p.20
Chapter 3.2.1 --- Our problem formulation
Chapter 3.2.2 --- Comparison between our problem formulation and traditional problem formulation
Chapter 3.3 --- Description of the Algorithm --- p.26
Chapter 3.3.1 --- Wagner-Whitin algorithm
Chapter 3.3.2 --- Transportation problem
Chapter 3.3.3 --- Consistence test
Chapter 3.3.4 --- Subgradient optimization
Chapter 3.3.5 --- Computation of lower bound
Chapter 3.4 --- Design of Experiment --- p.43
Chapter 3.4.1 --- Product demands
Chapter 3.4.2 --- Setup costs
Chapter 3.4.3 --- Setup times
Chapter 3.4.4 --- Capacity costs
Chapter 3.4.5 --- Inventory holding costs
Chapter 3.4.6 --- Quantity of capacity available for production
Chapter 3.4.7 --- Capacity absorption rate
Chapter 3.4.8 --- Generation of larger problems
Chapter 3.4.9 --- Initialization of Lagrangean multipliers
Chapter 3.4.10 --- Close test
Chapter 3.5 --- Open test --- p.58
Chapter 3.6 --- Managerial Implications --- p.61
Chapter 3.7 --- Summary --- p.61
Chapter Chapter 4 --- Capacitated Lot Sizing Problem without Setup Times --- p.63
Chapter 4.1 --- Overview --- p.63
Chapter 4.2 --- Problem Description and Formulation --- p.64
Chapter 4.3 --- Description of the Algorithm --- p.67
Chapter 4.3.1 --- Decomposition scheme
Chapter 4.3.2 --- Wagner-Whitin algorithm
Chapter 4.3.3 --- Transportation problem
Chapter 4.3.4 --- Subgradient optimization
Chapter 4.3.5 --- Computation of lower bound
Chapter 4.4 --- Design of Experiment --- p.80
Chapter 4.4.1 --- Product demands
Chapter 4.4.2 --- Setup costs
Chapter 4.4.3 --- Capacity costs
Chapter 4.4.4 --- Inventory holding costs
Chapter 4.4.5 --- Quantity of capacity available for production
Chapter 4.4.6 --- Capacity absorption rate
Chapter 4.4.7 --- Generation of larger problems
Chapter 4.4.8 --- Initialization of Lagrangean multipliers
Chapter 4.4.9 --- Selection of the extent of geometrical reduction and exponential smoothing
Chapter 4.4.10 --- Close test
Chapter 4.5 --- Open test --- p.92
Chapter 4.6 --- Managerial Implications --- p.95
Chapter 4.7 --- Comparison with other approaches --- p.96
Chapter 4.7.1 --- Gilbert and Madan's approach
Chapter 4.7.2 --- Our algorithm for CLS problem with setup time consideration
Chapter 4.8 --- Summary --- p.102
Chapter Chapter 5 --- Conclusion --- p.104
Appendix A Vogel's approximation method --- p.106
Bibliography --- p.107
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Chu, Fei Yao, and 費耀祖. "The Optimal Inventory Strategy of Economic Product Lot Size Model with Productive Conditions Changing." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/52134102863080737971.
Full textAbstract:
碩士淡江大學
管理科學研究所
81
Economic Production Lot Size model (or EPLS model) is de- signed for the manufacturing industry which manufacture and sale products simutaneously, offering references to the firms for planning its optimal inventory strategy. Two of the basic assumptions of the productive conditions of EPLS models are (1) the life cycle of product is infinite and (2) cost items are static during the cycle. The purpose of this paper is to investgate how the optemal inventory strategy will be influ- enced by changes of the previous assumptions. In this paper, on the basis of classical EPLS model, both previous assumptions are relaxed gradually. According to whe- ther the assumptions are relaxed or not, we construct four different types of EPLS models, discuss their inventory sys- tems and cost functions respectively, and find out their op- timal inventory strategies. All of the procedures of getting solutions can be written in computer programs to obtain the decision variables needed. Decision makers can put in parameters from different situa- tions to get the outcomes rapidly for planning and controlling their optimal inventory strategies.
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Chen, Hsin-Fen, and 陳杏棻. "Economic production lot size inventory models fordeteriorating items with time-dependent demand and variable production." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/55652186653848538002.
Full textAbstract:
碩士淡江大學
管理科學學系
88
Economic Production Lot Size model（EPLS model）is designed for the manufacturing industries which manufacture and sell products simultaneously, offering references to the firms for planning its optimal inventory strategy. In the traditional EPLS model, it is often assumed that the demand and production rate is constant In practice, demand rate always varies linearly with time. The production rate may be influenced by the on-hand inventory or by the demand. The phenomenon of deterioration occurs in many processes of inventory. In this situation, inventory level will be decreasing speedily. During the shortage period, the consumers may buy the goods from others. Thus, it causes opportunity cost. These changes of the costs will affect total cost of the inventory directly. Due to the factor considered above, in this study, two inventory models have been formulated. First, under the assumption of constant decay rate, we develop a EPLS inventory model of which demand is time-varying and production rate is the function of the on-hand inventory level. Secondly, the model is reformulated and solved under the assumption, thus, the production rate is dependent on demand rate and backlogging rate is constant. We discuss two inventory models and cost functions respectively and find out their optimal inventory strategies. Computer software can be used to obtain the decision variables needed in the procedures of getting solution. Additionally, in all mathematics inventory models built, numerical examples are provided to illustrate the proposed models, and sensitivity analysis is also provided. 第一章 緒 論 1 1.1 研究動機與目的 1 1.2 研究方法與求解步驟 3 1.3 研究結構 3 第二章 文獻探討 4 第三章 生產與存貨水準有關且需求隨時間變動之退化性產品的存貨模式 6 3.1 假設條件及符號說明 6 3.2 模式推導 8 3.3 各種成本的計算 12 3.4 模式求解 16 3.5 數值範例 18 3.6 敏感度分析 20 第四章 生產與需求函數有關且需求隨時間變動之退化性產品的存貨模式 30 4.1 假設條件及符號說明 30 4.2 模式推導 32 4.3 各種成本的計算 35 4.4 模式求解 39 4.5 數值範例 41 4.6 敏感度分析 44 第五章 結論與未來研究方向 55 5.1 結論 55 5.2 未來研究方向 56 參考文獻 57
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Yeh, Shu-Chun, and 葉淑君. "An Integrated Economic Lot Size Model for Central Factory JIT Purchasing and Satellite Factory Batch." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/66260159846072398035.
Full text
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鄭聖宏. "An economic production lot size inventory model for deteriorating items with-varying demand and production rate." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/61477146660969676143.
Full textAbstract:
碩士國立臺灣科技大學
工業管理系
92
ABSTRACT In this study, we discuss the “Economic Production Lot Size model” (EPLS model), which is an inventory model that manufacturing companies make and sell its goods at the same time. Different from the traditional EPLS model, we change several of its original hypotheses to make it fit the practical situation. For example, we assume that all products deteriorate as time goes by. And the production and demand rate will change with time and with the price of the products. We also hypothesize that shortage is allowed and demand during the stockout period is partially lost due to impatient customers. Moreover, the hypothesis of the finite planning horizon is discussed in this paper. Base on the hypotheses we mentioned above, three EPLS models about fixed deterioration rate have been developed. In chapter 2, we assumed that the production and demand rate change with time and partial backlogging is concerned. In chapter 3, we assumed that the production rate changes with time but the demand rate changes both with time and with the price of the product. In chapter 4, we assumed that production rate and demand rate change with time but the planning horizon is finite. In chapter 2 and chapter 4, the object is to find the minimum production cost per unit time and in chapter 3, the object is to find the maximum net profit per unit time. Each object function is respectively to find out their optimal inventory strategies. Finally, numerical examples are provided to illustrate the proposed model and sensitivity analysis is also provided.
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Wang, Ruei-Pei, and 王瑞培. "A Study of Economic Production rate & lot size for multi-production channels under limited capacity." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/39611620193470495355.
Full textAbstract:
碩士國立成功大學
工業與資訊管理學系碩博士班
94
In the past, for the traditional stable competition environment, manufacturers believed that they can continuously produce products and customers will buy any way. Manufacturers consider only their manufacture process instead of caring about the customers’ needs. However, the industry environment has changed. First of all, for customers with different procurement policies, manufacturers not only confront divinable and stable regular orders but also doubtable and unstable irregular orders. Therefore, this study considers both the regular and irregular orders to construct a model in dealing with the situation which manufacturers faced with uncertain demands. A capacity confirming mechanism is set up to examine the demand quantities. If the demand quantity is less than or equal to the capacity in the general production channel, the general supply channel is used to proceed the manufacturing procedure; if the demand quantity is greater than the capacity in the general production channel, the contingency supply channel is considered to use in addition to the general supply channel. The optimal values of production rate and production lot size for each channel are derived to provides effective information for production planning.
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Nananukul, Narameth 1970. "Lot-sizing and inventory routing for a production-distribution supply chain." Thesis, 2008. http://hdl.handle.net/2152/3960.
Full textAbstract:
The integration of production and distribution decisions presents a challenging problem for manufacturers trying to optimize their supply chain. At the planning level, the immediate goal is to coordinate production, inventory, and delivery to meet customer demand so that the corresponding costs are minimized. Achieving this goal provides the foundations for streamlining the logistics network and for integrating other operational and financial components of the system. In this paper, a model is presented that includes a single production facility, a set of customers with time varying demand, a finite planning horizon, and a fleet of vehicles for making the deliveries. Demand can be satisfied from either inventory held at the customer sites or from daily product distribution. A procedure centering on a reactive tabu search is developed for solving the full problem. After a solution is found, path relinking is applied to improve the results. A novel feature of the methodology is the use of an allocation model in the form of a mixed integer program to find good feasible solutions that serve as starting points for the tabu search. Lower bounds on the optimum are obtained by solving a modified version of the allocation model. Computational testing on a set of 90 benchmark instances with up to 200 customers and 20 time periods demonstrates the effectiveness of the approach. In all cases, improvements ranging from 10 - 20% were realized when compared to those obtained from an existing greedy randomized adaptive search procedure (GRASP). This often came at a three- to five-fold increase in runtime, however. A hybrid scheme that combines the features of reactive tabu search algorithm and branch-and-price algorithm is also developed. The combined approach takes advantage of the efficiency of the tabu search heuristic and the precision of the branch-and-price algorithm. Branching strategy that is suitable for the problem is proposed. Several advance techniques such as column generation heuristic and rounding heuristic are also implemented to improve the efficiency of the algorithm. Computational testing on standard data sets shows that a hybrid algorithm can practically solve instances with up to 50 customers and 8 time periods which is not possible by standard branch-and-price algorithm alone.text
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"Improved optimality conditions for the Wagner-Whitin algorithm." Chinese University of Hong Kong, 1988. http://library.cuhk.edu.hk/record=b5885937.
Full text
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"A genetic algorithm for the capacitated lot sizing problem with setup times." 2009. http://library.cuhk.edu.hk/record=b5894198.
Full textAbstract:
Chen, Jiayi.Thesis (M.Phil.)--Chinese University of Hong Kong, 2009.
Includes bibliographical references (p. 86-94).
Abstract also in Chinese.
Abstract --- p.i
Acknowledgement --- p.iv
Introduction --- p.1
Chapter 1.1 --- Introduction to the Capacitated Lot Sizing (CLS )problem --- p.1
Chapter 1.2 --- Our contributions --- p.2
Chapter 1.3 --- Organization of the thesis --- p.4
Literature Review --- p.5
Chapter 2.1 --- Research in CLS problem --- p.5
Chapter 2.1.1 --- Reviews in CLS problems --- p.8
Chapter 2.1.2 --- Approaches and methods to solve the traditional CLS problems --- p.9
Chapter 2.1.3 --- Research on Fixed-Charge-Transportation-typed models for CLS problems --- p.13
Chapter 2.2 --- Research in Genetic Algorithm (GA) --- p.15
Chapter 2.3 --- Conclusion --- p.17
Problem Description and Formulation --- p.18
Chapter 3.1 --- The formulation --- p.18
Chapter 3.2 --- Comparison with the traditional formulation --- p.24
Chapter 3.3 --- Conclusion --- p.28
Description of the Heuristic --- p.29
Chapter 4.1 --- Initialization --- p.32
Chapter 4.1.1 --- Setup string generation --- p.32
Chapter 4.1.2 --- Transportation problem --- p.35
Chapter 4.1.3 --- Consistency test --- p.47
Chapter 4.2 --- Selection --- p.50
Chapter 4.3 --- Crossover --- p.50
Chapter 4.4 --- Mutation --- p.52
Chapter 4.5 --- Evaluation --- p.53
Chapter 4.6 --- Termination --- p.54
Chapter 4.7 --- Conclusion --- p.54
Design of Experiments and Computational Results --- p.56
Chapter 5.1 --- Design of experiments --- p.57
Chapter 5.2 --- Discussion of lower bound procedures --- p.63
Chapter 5.3 --- Computational results --- p.65
Chapter 5.3.1 --- CLS problems with setup times --- p.65
Chapter 5.3.2 --- CLS problems without setup times --- p.77
Chapter 5.4 --- Conclusion --- p.82
Conclusion --- p.83
Bibliography --- p.86
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Lin, Chen-Hua, and 林楨樺. "Applying the Fixed Rate Approach to Solve the Cost and Warehouse Size of the Economic Lot Scheduling Problem." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/19371360582569802712.
Full textAbstract:
碩士東海大學
資訊管理學系
102
When a company does not have enough storage space, it must rent outsourcing warehouse space from other companies to store products. If this condition happening, a manager will need to consider (1) how to calculate the correct warehouse size and (2) how does the rent cost affect the average total cost. Therefore, this study discusses the above two issues when a company must rent outsourcing warehouse space from other companies. This research uses the fixed rate approach to solve the warehouse size and average total cost of the economic lot scheduling problem under the common cycle approach. Our approach applied the extra idle time for changing the production rate of one product in order to reduce the holding cost and warehouse rental cost. Most past researchers discussed the two issues above of the economic lot scheduling problem under the common cycle approach. They restrict the sequence all products strictly. However, they did not develop an effective approach for finding an optimal or near-optimal sequence/solution. Past researchers use the fixed rate approach to pick a product with the highest holding cost for changing its production rate. In this study, as applying the fixed rate approach to adjust the production rate of a product, it does not only affect the holding costs, but also impacts the warehouse rent costs. This study will investigate how to find a better production sequence and solution under the common cycle approach as applying the fixed rate approach. It also discusses how to pick a product in order to change its production rate when considering rent outsourcing warehouse space. Our study can help decision maker to schedule all products sequence, compute the related costs and rent right outsourcing warehouse space.
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Chen, Yun, and 陳蘊. "Applying the Flexible Rate Approach to Solve the Cost and Warehouse Size of the Economic Lot Scheduling Problem." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/49818517739058847990.
Full textAbstract:
碩士東海大學
資訊管理學系
103
The ELSP is concerned with the scheduling of cyclical production of n≥2 products on a single facility in equal lots over an infinite planning horizon, assuming stationary and known demands for each product. The objective of the ELSP is to determine the lot size and the schedule of production of each product so as to minimize the total cost incurred per unit time. When a company does not have enough storage space, it must rent an outsourcing warehouse space from other companies to store products. If this condition happening, a manager will need to consider following: (1) how to calculate the exact warehouse size and (2) how does the rent cost affect the average total cost. Therefore, this study discusses the above two issues as a company must rent an outsourcing warehouse space from other companies. This research uses the flexible rate method to solve the warehouse size and average total cost of the economic lot scheduling problem under the common cycle approach. Our approach applied the extra idle time for changing the production rate of one product in order to reduce the holding cost and warehouse rental cost. This study uses the flexible rate method to pick a particular product with the highest holding cost and change its production rate. In this study, as applying the flexible rate method to adjust the production rate of a product, it does not only affect the holding costs, but also impacts the warehouse rent sizes. This study will investigate how to apply the ant colony system to find a the optimal production sequence and solution under the common cycle approach. The numerical experiment shows our flexible rate method can obtain better solutions than the fixed rate method. Our study can help decision makers to schedule all products sequence, compute the related costs and rent the exact outsourcing warehouse space.
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Jiang, Li. "A fixed-effects model of the impact of minimum-lot-size zoning on residential development." 2008. http://hdl.rutgers.edu/1782.2/rucore10001600001.ETD.17502.
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BALLERINI, VERONICA. "Fisher's noncentral hypergeometric distribution and population size estimation problems." Doctoral thesis, 2021. http://hdl.handle.net/11573/1563206.
Full textAbstract:
Fisher’s noncentral hypergeometric distribution (FNCH) describes a biased urn experiment with independent draws of differently coloured balls where each colour is associated with a different weight (Fisher (1935), Fog (2008a)). FNCH potentially suits many official statistics problems. However, such distribution has been underemployed in the statistical literature mainly because of the computational burden given by its probability mass function. Indeed, as the number of draws and the number of different categories in the population increases, any method involving evaluating the likelihood is practically unfeasible. In the first part of this work, we present a methodology to estimate the posterior distribution of the population size, exploiting both the possibility of including extra-experimental information and the computational efficiency of MCMC and ABC methods. The second part devotes particular attention to overcoverage, i.e., the possibility that one or more data sources erroneously include some out-of-scope units. After a critical review of the most recent literature, we present an alternative modelisation of the latent erroneous counts in a capture-recapture framework, simultaneously addressing overcoverage and undercoverage problems. We show the utility of FNCH in this context, both in the posterior sampling process and in the elicitation of prior distributions. We rely on the PCI assumption of Zhang (2019) to include non-negligible prior information. Finally, we address model selection, which is not trivial in the framework of log-linear models when there are a few (or even zero) degrees of freedom.