Certains environnements ont besoin de plusieurs compilateurs, par exemple un pour le système d'exploitation, supportant la norme C/C++ complète, et l'autre pour les applications, qui supporte éventuellement un sous-ensemble de la norme, mais capable de fournir plus de performance. Le maintien de plusieurs compilateurs pour une plateforme cible représente un effort considérable. Il est donc plus facile d'implémenter et de maintenir un seul outil responsable des optimisations particulières au processeur ciblé. Il nous faut alors un moyen de relier ces compilateurs à l'optimiseur, de préférence, en gardant au passage certaines structures de données internes aux compilateurs qui, soit prendraient du temps, soit seraient impossible à reconstruire à partir du code assembleur par exemple. Dans cette thèse, nous introduisons Tirex, une représentation textuelle intermédiaire pour échanger des informations de bas niveau, déjà dépendantes de la cible, entre les compilateurs, les optimiseurs et les autres outils de la chaîne de compilation. Notre représentation contient un flot d'instructions du processeur cible, mais garde également la structure explicite du programme et supporte la forme SSA (Static Single Assignment). Elle est facilement extensible et très flexible, ce qui permet de transmettre toute donnée jugée importante à l'optimiseur. Nous construisons Tirex par extension de MinIR, une représentation intermédiaire elle-même basée sur un encodage YAML des structures du compilateur. Nos extensions de Tirex comprennent: l'abaissement de la représentation au niveau du processeur cible, la conservation du flot de données du programme, ainsi que l'ajout d'informations sur les structures de boucles et les dépendances de données. Nous montrons que Tirex est polyvalent et peut être utilisé dans une variété d'applications différentes, comme par exemple un environnement d'exécution virtuel (VEE),et fournit une base forte pour un environnement d'analyse du programme. Dans le cadre d'un VEE, nous présentons un interprèteur de la forme SSA et un compilateur just-in-time (JIT). Nous montrons comment l'interprétation d'une représentation au niveau du processeur cible élimine la plupart des problèmes liés à l'exécution en mode mixte. Nous explorons également les questions liées à l'interprétation efficace d'une représentation de programme sous la forme SSA. / Some environments require several compilers, for instance one for the operating system, supporting the full C/C++ norm, and one for the applications, potentially supporting less but able to derive more performance. Maintaining different compilers for a target requires considerable effort, thus it is easier to implement and maintain target-dependent optimizations in a single, external tool. This requires a way of connecting these compilers with the target-dependent optimizer, preferably passing along some internal compiler data structures that would be time-consuming, difficult or even impossible to reconstruct from assembly language for instance. In this thesis we introduce Tirex, a Textual Intermediate Representation for EXchanging target-level information between compilers, optimizers an different tools in the compilation toolchain. Our intermediate representation contains an instruction stream of the target processor, but still keeps the explicit program structure and supports the SSA form(Static Single Assignment). It is easily extensible and highly flexible, which allows any data to be passed for the purpose of the optimizer. We build Tirex by extending the existing Minimalist Intermediate Representation (MinIR), itself expressed as a YAML textual encoding of compiler structures. Our extensions in Tirex include: lowering the representation to a target level, conserving the program data stream, adding loop scoped information and data dependencies. Tirex is currently produced by the Open64 and the LLVM compilers, with a GCC producer under work. It is consumed by the Linear Assembly Optimizer (LAO), a specialized, target-specific, code optimizer. We show that Tirex is versatile and can be used in a variety of different applications, such as a virtual execution environment (VEE), and provides strong basis for a program analysis framework. As part of the VEE, we present an interpreter for a Static Single Assignment (SSA) form and a just-in-time (JIT) compiler. We show how interpreting a target-level representation eliminates most of the complexities of mixed-mode execution. We also explore the issues related to efficiently interpreting a SSA form program representation.

Neste estudo, foi comparada a eficácia de dois modelos de gestão de materiais: o primeiro foi o modelo tradicional, com controle manual e com reposição de estoque baseado em cotas preestabelecidas, adotado pelo Hospital Universitário da Universidade de São Paulo (HU-USP), desde 1981; e o segundo modelo, implementado em 2008, com gestão informatizada e reposição de estoque segundo os princípios do just in time. Assim, os objetivos específicos foram comparar a quantidade e o custo dos materiais médico-hospitalares consumidos e em estoque antes e após a implantação do Sistema de Gestão de Materiais informatizado (SGM) e, identificar o consumo dos kits cirúrgicos e anestésicos após a implantação do novo sistema. Trata-se de um estudo comparativo com abordagem quantitativa, desenvolvido no Centro Cirúrgico do HU-USP. Para a coleta de dados, foram utilizados quatro instrumentos: planilha de movimento cirúrgico e a caracterização do paciente; planilha de consumo do material; planilha de kits cirúrgicos e anestésicos; e a planilha de dados sobre estoque de materiais. A população foi constituída por 400 itens de materiais médico-hospitalares do setor de Centro Cirúrgico, no período de fevereiro a maio de 2007 e fevereiro a maio de 2008. Os resultados mostraram que o consumo de materiais do Centro Cirúrgico em 2008 reduziu 8,13% em relação ao ano de 2007 e o custo total dos materiais consumidos tiveram um acréscimo de 2,20%, não tendo representação estatística significativa. Quanto aos kits de procedimentos cirúrgicos e anestésicos, nos quatro meses estudados no ano de 2008, 64,7% do consumo de materiais fizeram parte do kit e 35,3% foram materiais avulsos consumidos durante a cirurgia. Foram utilizados 81tipos de kits sendo que, 54 (66,6%) apresentaram um consumo de material abaixo de 51,9%. Houve uma redução de materiais em estoque no Centro Cirúrgico em 2008 de 26,22% em relação ao ano de 2007 e uma redução de 12,46% do custo / This study involved the comparison of the efficiency of two models of management of hospital medical materials: the first was the traditional model, manually controlled and with stock reposition based on pre-determined quotas adopted by the Hospital Universitário of the University of São Paulo (HU-USP) since 1981; the second model, implemented in 2008, was under an automated management and stock reposition system following the just-in-time parameters. The specific objectives of the study were thus (1) to compare the volume and the cost of the hospital medical materials used with the ones remained in stock before and after the implementation of the automated System of Management of Materials (SGM-Sistema de Gestão de Materiais); and (2) to determine the use of surgical kits and anesthetics also after the implementation of the new system. It also focused on a quantitative approach adopted in the Surgical Center of HU-USP. To achieve a comprehensive result, four types of Control Sheets were used to assemble the data: the surgical activity and the status of the patient; the volume of the material used; the surgical kits and anesthetics; and on the data of the stock of materials. The analysis involved 400 items of hospital medical materials of the Surgical Center sector in the month-periods of February to May of 2007 and of 2008. The results indicated an 8.13% reduction in the use of materials in the Surgical Center in 2008 as compared to 2007, and an increase of 2.20% in the total cost of material, the latter considered to be of no statistical significance. As far as the kits of surgical procedures and anesthetics are concerned, in the four-month period of 2008, 64.7% of the use of materials was out of the kit, and 35.3% represented other assorted materials used during the surgeries. 81 types of kits were used of which 54 (66.6%) decreased 51.9% in the use of kit-related materials. In 2008 there was a 26.22% stock reduction of materials in the Surgical Center as compared to 2007 and a 12.46% cost reduction

Este trabalho apresenta procedimentos que podem ser utilizados na programação da produção em um ambiente JIT. Esses procedimentos deveriam ser utilizados em sistemas clássicos de programação, onde a utilização do sistema kanban é inviável. O caso estudado se baseia em uma única máquina, com datas de entrega múltiplas e com penalidades distintas de adiantamento e de atraso para cada ordem. O objetivo a ser alcançado é a minimização do custo total. Para isso, é utilizado um procedimento de busca denominado beam search, para gerar as seqüências, e um algoritmo de inserção de ociosidade, para definir os programas. O algoritmo utilizado é uma generalização do algoritmo de GAREY et al. (1988) onde as penalidades são distintas para adiantamento e para atraso. O procedimento e o algoritmo são testados em várias condições sendo comparados com regras de despacho e com a função EXP-ET. Quando a função EXP-ET é utilizada com a possibilidade de inserção de ociosidade, o período de ociosidade ótimo é determinado. Assume-se que a dificuldade de solução do problema é dependente de dois parâmetros clássicos: fator de atraso médio e amplitude relativa das datas de entrega. Testes empíricos comparativos são realizados através de simulação computacional, onde se mede o tempo de solução e o valor alcançado pela função objetivo. Os resultados indicam que o desempenho dos vários procedimentos testados é altamente dependente dos dois parâmetros, mostrando que para a escolha de um procedimento apropriado, deve-se primeiramente conhecer o valor dos parâmetros. São fornecidos os resultados encontrados e os códigos computacionais utilizados no estudo. / This work presents some procedures which can be used in production scheduling problems in JIT environments. These procedures may be used in cases of classical production scheduling where the use of the kanban system is infeasible. The case studied is based on a single machine, with multiple due dates, and distinct earliness and tardiness penalties for each job. The objective function is to minimize total cost. A heuristic search procedure known as beam search is used to construct sequences of jobs, and an idleness insertion algorithm is used to obtain schedules. The algorithm used is a generalization of the GAREY et al. (1988) algorithm, where penalties are distinct for earliness and tardiness. The procedure and algorithm are tested in many conditions involving comparisons with dispatching rules and the EXP-ET function. When EXP-ET function is applied with possibility of idleness insertion, the optimal idleness period is provided. It was assumed that problem hardness is dependent on two classical parameters: average tardiness factor and relative range of due dates. Empirical comparative tests are conducted with computational simulation, where computational solution time and objective function value are evaluated. Results indicate that procedures performance is highly dependent on both parameters, showing that is necessary to know parameters values before choosing an appropriate procedure. The detailed results and computational code used in this study are also provided.

Řada programovacích jazyků byla schopna zvýšit svoji rychlost výměnou běhových systémů stavěných na míru za obecné platformy, které pro optimalizaci používají just-in-time překlad, jako jsou GraalVM nebo RPython. V této práci vyhodnocuji, zda je použití takovýchto platforem vhodné i pro jazyky se závislymi typy nebo důkazovými systémy. Tato práce představuje koncepty -kalkulu a teorie typů potřebné pro úvod do závislých typů s relevantními algoritmy, specifikuje malý závisle typovaný jazyk založený na $\lambda\Pi$ kalkulu, a prezentuje dva interpretery tohoto jazyka. Tyto interpretery jsou psané v jazyce Kotlin, první je jednoduchý, psaný ve funkcionálním stylu a druhý používá platformu GraalVM a Truffle. GraalVM je platforma založená na virtuálním stroji Javy (JVM), která přidává just-in-time překladač založený na částečném vyhodnocení (partial evaluation) a Truffle je knihovna pro tvorbu programovacích jazyků využívající tento překladač. Závěr práce vyhodnocuje běhové charakteristiky těchto interpreterů na různých zátěžových testech.Závěry práce jsou ale silně negativní. Vliv JIT překladu není znatelný ani přes snahu optimalizovat běžné algoritmy z teorie typů, které jsou zjevně nevhodné pro platformu JVM. Práce končí návrhy několika navazujících projektů, které by lépe využily možnosti Truffle a které by byly vhodnější pro implementaci závisle typovaných jazyků.

Sea Traffic Management has developed with the aim of facilitating work and increasing efficiency at sea, both in terms of productivity and environmental contexts. The technical development and digitization of the equipment on ships has led to new problems that have been developed such as cyber-attacks and technical problems. This study is based on a qualitative research method. The purpose of the work is to investigate how effective STM is and how safe it is to use for merchant vessels. The study showed that STM can have a positive effect on the environment and increase time savings, provided that more vessels in the industry use it as standard equipment. Results indicate that Sea Traffic Management is a helpful tool that will increase safety for navigation and have a positive effect on the environment for longer sea voyages. However, this is assumed if the shipping industry itself is ready for a digitalized world that is constantly developing, where a new type of issues arises with a nuanced threat for both ships and land bases. / Sea Traffic Management har utvecklats i syfte att underlätta arbetet och öka effektiviteten till sjöss, både när det gäller i produktivitet samt i miljösammanhang. I samband med den tekniska utvecklingen och digitaliseringen av utrustningen på fartyg så har nya lösningar samt problem uppstått, såsom cyberattacker och tekniska bekymmer. Studien grundar sig i en kvalitativ forskningsmetod. Arbetet har i syfte att undersöka hur effektivt STM är samt hur säker den är för användning av olika handelsfartyg på marknaden. I studien visade det sig att STM kan påverka miljön positivt samt öka tidsbesparingar förutsatt att fler fartyg inom branschen nyttjar det som en standardutrustning. Resultat tyder på att Sea Traffic Management är ett hjälpsamt verktyg som kommer att öka säkerheten för navigeringen samt påverka miljön positivt för längre sjöresor. Detta är dock förutsatt om själva sjöfartsbranschen är redo för en digitaliserad värld som ständigt utvecklas, där en ny typ av problematik uppstår med en nyanserad hotbild för både fartyg och olika land baser.

Efterfrågan på bostäder är idag större än på länge samtidigt som byggbranschen kämpar med pressade byggtider och låga vinstmarginaler. Vinstmarginalen kan ökas genom att effektivisera logistiken och eliminera onödiga kostnader som uppstår i samband med bristande planering. Syftet med rapporten är att hjälpa Peab att identifiera var onödiga kostnader uppstår i samband med hantering av prefabricerade stomelement. Detta sker genom att jämföra arbetet med logistikfrågor på två likvärdiga Peab-projekt, vilka är KTH-studentbostäder samt Roddaren och Simmaren. Resultatet bygger till största del på djupgående intervjuer med nyckelpersoner på respektive projekt. En enkätundersökning gjordes som ett komplement till resultatet från intervjuerna. Rapporten visar att arbetet med logistikfrågor skiljer sig mellan de två projekten. Slöseri på grund av brister i den interna kommunikationen finns på båda arbetsplatserna. Gemensamt är även slöseri till följd av avsaknad av tydliga rutiner för dokumentation av dolda felkostnader. Det största identifierande slöseriet på den enskilda arbetsplatsen var slöseri till följd av fel lastordning på projekt Roddaren och Simmaren vilket lett till både synliga och dolda kostnader. / Demand for housing is today greater than in a long time, whilst the construction industry is struggling with the pressure to shorten construction schedules and low profit margins. The profit margin can be increased by streamlining logistics and eliminating unnecessary costs arising from lack of planning. The purpose of the report is to help Peab identify where unnecessary costs arise in the handling of prefabricated concrete elements. This is done by comparing the work on logistics issues to two equivalent Peab-projects, KTH-studentbostäder and Roddaren and Simmaren. Results are largely based on in-depth interviews with key people on each project. A survey was conducted as a complement to the results of the interviews. The report shows that the work on logistics issues differs between the two projects. Wastage due to shortcomings in internal communication are found at both workplaces. They also have in common wastage due to lack of clear procedures for documenting the cost of hidden errors. The biggest identifiable waste at the individual workplace was waste as a result of wrong loading order on the Roddaren and Simmaren projects, which led to both visible and hidden costs.

I delar av byggbranschen finns idag ett gemensamt problem som kan beskrivas med termen dålig framförhållning. Detta försvårar möjligheten att se bygglogistiken i ett helhetsperspektiv, både för leverantören och entreprenören, men tyvärr även för övriga aktörer inblandade i byggproduktionsprojekt. Att uppnå bra bygglogistik med ökad hänsyn till miljön kräver ett gott samarbete mellan samtliga parter. Bygglogistik är planering flera (många) veckor framåt, i byggbranschen är det vanligt att det uppkommer oväntade händelser som leder till att tidsplaner för olika delar i byggprojektet justeras. I dagsläget är det lite för ofta som justeringar sker ”i sista minuten”. Detta leder till dyrare frakter, svårigheter att klara av en bra leveransprecision vilket i sin tur påverkar effektiviteten i bygglogistiken negativt. Problemen som upptäckts för de olika processerna inom bygglogistiken på Cramo är beskrivna med åtgärdsförslag, rekommendationer för effektivisering/förbättring av bygglogistik under rubriken probleminventering. För detta arbete har faktainsamlingen omfattat metoderna i lean construction som JIT- Just in time och jämförelser mellan olika tilläggstjänsterna som används i byggbranschen idag. Även fakta om kommunikationssystemet, TMS, samt läran om transport och materialhantering har undersökts och analyserats. Fakta från intervjuerna som beskriver TMS, transport metoder och lösningar samt hur hantering av material sker och vad man har för mål i framtiden har redovisats i bakgrunden, resultatet samt i analysen. Bygglogistik är kortfattat en samlings ord för alla aktiviteter som leder till att rätt produkt ska vara på rätt plats vid rätt tillfälle. “Tänk efter före”(Sundin, 2019) / In the construction industry, there is a general industry problem that can be described by the term poor advance planning. This makes it difficult to see the construction logistics in a holistic perspective, both for the supplier and the contractor, but unfortunately also for other parties involved in construction production projects. Achieving good building logistics with consideration for the environment requires good cooperation between all parties. Building logistics is planning several (many) weeks ahead, in the construction industry it is common that unexpected events arise that lead to adjusting timetables for different parts of the construction project. At present, it is a little too often that adjustments are made "at the last minute". This leads to more expensive freight, difficulties in coping with a good delivery precision, which in turn negatively affects the efficiency of construction logistics. Problems that has been discovered for the different parts of the process within building logistics in CRAMO are presented with solutions, recommendation of efficiency/improvement for building logistics under the title problem inventory,”problem inventering”. In problem inventory, these are described while action proposals are presented later in the report during the analysis. For this work, the facts have included the methods in lean construction as JIT- Just in time and comparisons between various additional services used in the construction industry today. Facts about the communication system, TMS, and the doctrine of transport and material handling have also been investigated and analyzed. Facts from the interviews that describe TMS, transport methods and solutions as well as how material handling takes place and what one has for goals in the future have been reported in the background, the result and in the analysis. Building logistics is briefly a term for all activities that lead to the right product being in the right place at the right time. "Think ahead" (Sundin, 2019)

Många företag har problem med höga lagernivåer. Det innebär att hanteringskostnader ökar och att material lagras i långa perioder. Företag eftersträvar att sänka sina lagernivåer, utan att riskera att lagret blir tomt eller att material saknas. I denna studie kommer ett fallföretag att analyseras, där orsaken till höga lagernivåer och dyra hanteringskostnader identifieras. Det teoretiska ramverket är baserat på vetenskapliga artiklar, som är peer-review granskade. Teorin som används i studien är Lean, Just-in-Time (JiT), First-in-First-out (FIFO), leverantörsstyrda lager och leverantörsrelationer. Det empiriska materialet är framställt av information som framkommit under semistrukturerade intervjuer. Teorin har tillsammans med det empiriska materialet analyserats med hjälp av en tematisk analysmetod. En av orsakerna till att lagernivåerna är höga är på grund av att komponenterna beställs efter prognoser som är bristfälliga. En annan orsak är att företaget inte arbetar efter en tydlig strategi. Det resulterar i att materialet ankommer långt innan behovet och behöver lagras i flera månader. Resultatet visar att företaget kunnat använda JiT, eftersom det skulle innebära att materialet ankommer när ett behov finns. Det skulle resultera i att komponenterna inte behöver lagras under långa perioder, vilket även reducerar hanteringskostnaderna. En risk med JiT är att det kan bli materialbrist vid leveransstörningar, något som kan undvikas med hjälp av säkerhetslager. Fallföretaget har långa ledtider på vissa komponenter, något som gör att de beställer större kvantiteter och lagrar. Detta kan undvikas med leverantörsstyrda lager, då leverantörerna har ett färdigvarulager för att reducera ledtiderna. FIFO är ett bra lagringsalternativ för att reducera lagringstiden, men det kräver bra förutsättningar för att det ska fungera bra. För att undvika slöseri så hade Lean kunnat implementeras. / Numerous companies have problems with high inventory levels. Which in many cases lead to increasing handling costs, and materials being stored for a long period of time. Companies strive to reduce their inventory levels, without risking the warehouse going empty or lacking material. In this study a case company will be analysed in order to identify the cause of high inventory levels and expensive handling costs. The theoretical framework is based on peer- reviewed scientific articles. Focusing mainly on the theories of Lean, Just-in-Time (JiT), First- in-First-out (FIFO), Vender management inventory and Supplier Relationship. The empirical material is collected through semi-structured interviews. Together with the empirical material, the theory has been analysed using a thematic analysis method. One of the reasons why inventory levels are high, is because the components are ordered based on forecasts that are insufficient. Another reason is that the company does not work according to any strategy. Which is causing the material to arrive before the demand appears, requiring it to be stored for several months in advance. The result shows that the company should consider using JiT and have the material arrive once there is an actual material demand. The risks with JiT are that there could be material shortages, which could be avoided with safety stocks. The case company has long lead times on certain components, meaning that they order larger quantities and stock. This can be avoided with vender management inventory, as the suppliers have a stock of finished goods to reduce lead times. FIFO is a good storage method, but it requires good conditions to work well. To avoid waste, Lean could have been implemented.

Thesis (MBA)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: This report details the critical success factors for consideration in developing a quick response (QR) supply chain strategy for fashion apparel retailers in South Africa. Quick response is the recent supply chain management development that supports a fast fashion business model most evident within the North American and European fashion apparel market. A QR supply chain strategy differs from previous supply chain management principles as it utilises consumer data to create a demand driven network in order to co-ordinate functions through the supply chain. This differs from the standard ‘push’ model evident within the normal fashion apparel cycle and follows a more consumer-centric approach to product demand. The continued success and growth of four of the global fashion apparel, retail organisations as listed by Deloitte’s Global Powers of Retailing 2014 survey, is attributed to the ability of these retailers to respond in season to consumer demand. These leading organisations have effectively adapted and incorporated a QR strategy into their broader competitive offering. South African fashion apparel retailers have recently begun introducing the philosophy and operational strategy of QR to their overriding business strategy, however, current implementation is limited and the full advantages of QR practises in comparison to the northern hemisphere markets is not being realised. Based on the limited amount of local retail and manufacturing QR information, limited availability of sales data for statistical analysis, increasing levels of competition and slow economic growth, a clear understanding of QR is needed. Critically, phased implementation of QR in South Africa requires a clear understanding of the critical success factors (CSF) needed for upfront engagement between retailers and manufacturers. The primary research question was therefore, what are the critical success factors for QR implementation in the South African fashion apparel sector? The purpose of this research was to define a priority list of critical success factors for consideration by defining the scope of QR thinking within business and clarifying the degree and level of application in northern hemisphere markets as lessons for the local sector. Three research aspects were conducted in determining the critical success factors for South Africa. An academic literature review was used to describe the development of QR and identify those factors within the field of supply chain management. This was used to define the scope of questions and themes for interviews with local industry professionals. The results of these interviews were then compared to insights from case studies of global, fast fashion retailers in order to define the priority list of factors. The primary findings for the South African retail sector were: that effective QR implementation should be strongly aligned to the strategic positioning of retail and manufacturing cluster of organisations. Detailed consideration of the benefits for both supply chain members, as well as the level of communication and exchange of information was critical in developing the responsiveness required from the supply chain. Collaborative product design featured frequently within the research and required new processes and organisational structures to be implemented effectively. The findings of the research provide a concise, viable set of factors for retail and manufacturing engagement. These factors can be used to structure long term, sustainable quick response practises to enable greater adoption and implementation within the South African sector. This will encourage more close-to-home product development and enable retailers to better utilise local manufacturing resources while remaining competitive.

A just-in-time supply pickup and delivery system (JSS) manages the logistic operations between a manufacturing plant and its suppliers by controlling the sequence, timing, and frequency of container pickups and parts deliveries, thereby coordinating internal conveyance, external conveyance, and the operation of cross-docking facilities. The system is important to just-in-time production lines that maintain small inventories. This research studies the logistics, supply chain, and production control of JSS. First, a new meta-heuristics approach (taboo search) is developed to solve a general frequency routing (GFR) problem that has been formulated in this dissertation with five types of constraints: flow, space, load, time, and heijunka. Also, a formulation for cross-dock routing (CDR) has been created and solved. Second, seven issues concerning the structure of JSS systems that employ the previously studied common frequency routing (CFR) problem (Chuah and Yingling, in press) are explored to understand their impacts on operational costs of the system. Finally, a discreteevent simulation model is developed to study JSS by looking at different types of variations in demand and studying their impacts on the stability of inventory levels in the system. The results show that GFR routes at high frequencies do not have common frequencies in the solution. There are some common frequencies at medium frequencies and none at low frequency, where effectively the problem is simply a vehicle routing problem (VRP) with time windows. CDR is an extension of VRP-type problems that can be solved quickly with meta-heuristic approaches. GFR, CDR, and CFR are practical routing strategies for JSS with taboo search or other types of meta-heuristics as solvers. By comparing GFR and CFR solutions to the same problems, it is shown that the impacts of CFR restrictions on cost are minimal and in many cases so small as to make simplier CFR routes desirable. The studies of JSS structural features on the operating costs of JSS systems under the assumption of CFR routes yielded interesting results. First, when suppliers are clustered, the routes become more efficient at mid-level, but not high or low, frequencies. Second, the cost increases with the number of suppliers. Third, negotiating broad time windows with suppliers is important for cost control in JSS systems. Fourth, an increase or decrease in production volumes uniformly shifts the solutions cost versus frequency curve. Fifth, increased vehicle capacity is important in reducing costs at low and medium frequencies but far less important at high frequencies. Lastly, load distributions among the suppliers are not important determinants of transportation costs as long as the average loads remain the same. Finally, a one-supplier, one-part-source simulation model shows that the systems inventory level tends to be sticky to the reordering level. JSS is very stable, but it requires reliable transportation to perform well. The impact to changes in kanban levels (e.g., as might occur between route planning intervals when production rates are adjusted) is relatively long term with dynamic after-effects on inventory levels that take a long time to dissapate. A gradual change in kanban levels may be introduced, prior to the changeover, to counter this effect.