Dissertations / Theses: 'Rolling planning'

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GOMES, ULISSES ROCHA. "COLD-ROLLING PROCESS OPTIMIZATION BY MEANS EXPERIMENT PLANNING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10090@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
Esta dissertação teve como objetivo desenvolver um modelo através da técnica de planejamento de experimentos aplicado ao processo de laminação a frio para fabricação de aços especiais utilizados no segmento de mercado de bebidas carbonatadas. O processo consiste na transformação através da redução da espessura de uma bobina de aço laminada a quente e depois decapada para remoção do óxido, em uma bobina com espessura final desejada pelo cliente. Este processo envolve variáveis controláveis e não controláveis, que interagem umas com as outras afetando a variável resposta que é a espessura final do produto. As questões fundamentais são entender como as variáveis controláveis afetam a variável resposta? Quais são as mais influentes? Existem interações entre estas variáveis? É possível elaborar um modelo adequado para o problema? A técnica do planejamento fatorial fracionado não só torna possível encontrar tais respostas para as questões levantadas, mas também, abre novas perspectivas de aplicação desta poderosa ferramenta nos processos de produção, onde é bastante comum encontrar situações semelhantes ao estudo proposto por este trabalho. A realização deste projeto compreendeu, uma descrição do problema, uma revisão bibliográfica com as etapas necessárias para execução de um planejamento de experimentos, escolha das variáveis controláveis que integraram o experimento, a execução do experimento, a análise dos resultados, uma abordagem dos Modelos Lineares Generalizados e validação do modelo através de ajuste dos parâmetros do processo conforme indicado através da análise dos resultados. A aplicação desta metodologia e a implementação das alterações propostas proporcionaram robustez ao processo de forma que mesmo quando ocorrem as perturbações das variáveis não controláveis, ainda assim a espessura permanece dentro das tolerâncias especificadas. Proporcionou ainda uma redução na variação de ± 1.5% para ± 1.0% , quando era de se esperar a necessidade de investimentos em tecnologia o que tornaria o produto mais caro e menos competitivo frente aos sucedâneos. Os resultados alcançados possibilitam a defesa de mercado através de uma maior competitividade obtida pelo menor custo dos produtos em aço.
This dissertation aims to develop a model by using experiment planning techniques applied to cold-rolling process to manufacture special steels utilized in the carbonated beverage market segment. The process consists of downgauging hot-rolled coil, which is further pickled for oxide removal, into a coil with the final thickness required by customer. It involves controlled and uncontrolled variables, which interact with one another, thus affecting the response variable, i..e, product´s final thickness. Some of the fundamental questions to be asked include: How do controlled variables affect response variable? What are the most influential ones? Are there interactions among such variables? Is it possible to work out an appropriate model to address this problem? The fragmented factor planning technique provides answers to the questions raised, by breaking new grounds in terms of using this powerful tool in manufacturing processes , where situations similar to those suggested by this study are fairly common. It includes a description of the problem, a bibliography review with the required steps to conduct the experiment planning, choice of controlled variables which make up the experiment as well as its execution, result analysis, an approach to Generalized Linear Models, and validation of model by adjusting process analysis as shown in the result analysis. Applying this methodology and implementing the proposed changes bolstered the process in such a way that even when disturbances of uncontrolled variables occur the thickness remains within the specified tolerances. Additionally, a further reduction in variation ranging from ± 1.5% to ± 1.0% was achieved, where technology investment would be required, thereby making steel products more expensive and less competitive against other competing products, thus ensuring competitiveness.

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Husseini, Seyed M. M. "Computer aided process planning (CAPP) for flat rolling of copper alloys." Thesis, Aston University, 1989. http://publications.aston.ac.uk/11883/.

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The manufacture of copper alloy flat rolled metals involves hot and cold rolling operations, together with annealing and other secondary processes, to transform castings (mainly slabs and cakes) into such shapes as strip, plate, sheet, etc. Production is mainly to customer orders in a wide range of specifications for dimensions and properties. However, order quantities are often small and so process planning plays an important role in this industry. Much research work has been done in the past in relation to the technology of flat rolling and the details of the operations, however, there is little or no evidence of any research in the planning of processes for this type of manufacture. Practical observation in a number of rolling mills has established the type of manual process planning traditionally used in this industry. This manual approach, however, has inherent drawbacks, being particularly dependent on the individual planners who gain their knowledge over a long span of practical experience. The introduction of the retrieval CAPP approach to this industry was a first step to reduce these problems. But this could not provide a long-term answer because of the need for an experienced planner to supervise generation of any plan. It also fails to take account of the dynamic nature of the parameters involved in the planning, such as the availability of resources, operation conditions and variations in the costs. The other alternative is the use of a generative approach to planning in the rolling mill context. In this thesis, generative methods are developed for the selection of optimal routes for single orders and then for batches of orders, bearing in mind equipment restrictions, production costs and material yield. The batch order process planning involves the use of a special cluster analysis algorithm for optimal grouping of the orders. This research concentrates on cold-rolling operations. A prototype model of the proposed CAPP system, including both single order and batch order planning options, has been developed and tested on real order data in the industry. The results were satisfactory and compared very favourably with the existing manual and retrieval methods.

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Zhu, Xiang. "Replenishment strategy and coordination with quantity flexibility in a rolling-horizon environment /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?IELM%202006%20ZHU.

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Pandravada, Ratnam. "Kinematics and motion planning of a rolling disk between two planar manipulators." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1178049004.

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Ventola, David P. "Order combination methodology for short-term lot planning at an aluminum rolling facility." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13441.

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Reiners, Christoph [Verfasser], and Alf [Akademischer Betreuer] Kimms. "Constraint Programming-Based Heuristics for the Multi-Depot Vehicle Routing Problem with a Rolling Planning Horizon / Christoph Reiners. Betreuer: Alf Kimms." Duisburg, 2016. http://d-nb.info/1081899670/34.

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Tréfond, Sabine. "Planification robuste des roulements d’engins dans le domaine ferroviaire." Thesis, Paris, CNAM, 2014. http://www.theses.fr/2014CNAM0921/document.

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Cette thèse est consacrée à la planification robuste du matériel roulant ferroviaire dans un contexte de transport de voyageurs régional. Il s'agit de déterminer pour chaque engin une suite de trajets à réaliser sur une période donnée de façon à résister au mieux aux aléas pouvant apparaître en opérationnel. Dans ce but, nous proposons une définition et une caractérisation de la robustesse par des indicateurs propres au contexte d'étude. Nous abordons le problème par une approche structurelle différente des approches robustes classiques qui permet d'agir sur la structure d'une solution en fonction des indicateurs définis. Trois méthodes sont alors mises en œuvre dans le cadre de ce travail. Une résolution approchée par une heuristique gloutonne et une recherche locale permet d'obtenir des solutions rapidement. Une méthode de résolution approchée par génération de colonnes a été développée afin de prendre en compte plus de contraintes de façon intégrée. Une méthode basée sur un programme linéaire en nombres entiers résolu exactement traite un problème plus général. Afin de limiter le coût de la robustesse, ces méthodes sont basées sur un existant à SNCF répondant au problème de planification des ressources matérielles à coûts de production minimaux. Un outil de simulation du comportement des solutions en situation perturbée permet de comparer les solutions entre elles par évaluation des indicateurs de robustesse. Des expérimentations sur des instances réelles ont prouvé la pertinence des approches et ont mené à l'industrialisation d'un prototype
This thesis deals with robust rolling-stock planning problems for passenger regional trains. It consists in building robust rolling-stock schedules to operate trains under technical constraints while anticipating operational disturbances that can occur. First of all, we define indicators to characterize robustness in context. We use these indicators to have an effect on solutions that we build. This structural approach is unusual compared to classical robust optimization approaches. We have implemented three methods to solve the problem. A sequential heuristic method enhanced by a local search gives solutions quickly. A column-generation method calculates approximate solutions.An integer linear program is solved exactly to obtain solutions to a global problem. These methods are based on an existing tool at SNCF that optimizes the rolling-stock planning problem to assure optimal production costs. A simulation tool evaluates robustness indicators to compare solutions. Tests on real instances have proved the relevance of the approaches and have lead to the use of a prototype in production

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Kanmert, Jacob, Joakim Lindh, and Joel Welin. "Prestationsmätning i komplexa projekt : - En fallstudie på Saab Aeronautics." Thesis, Linnéuniversitetet, Institutionen för maskinteknik (MT), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75059.

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Organisationer med komplexa projekt som sträcker sig över ett flertal år finner svårigheter att förhålla sig till projektens fördefinierade parametrar tid, kostnad och omfattning. Skenande kostnader och förseningar är vanligt förekommande i dessa typer av projekt, då projekten omfattar ett samspel av ett flertal aktiviteter och där projektets omfattning ofta förändras. Det finns metoder som verksamheter kan tillämpa för att kontrollera ovannämnda parametrar och i ett tidigt skede kunna identifiera när någon av parametrar tenderar att överskridas. En metod som styrker prestationsmätningar är Earned Value Mangament, EVM. Syftet med studien var att identifiera vart organisationer brister gentemot branschstandarden inom EVM, ANSI/EIA-748. Standarden innehåller viktiga steg för att kunna utföra en korrekt prestationsmätning tillsammans med teorin från Earned Value Management. Resultat studien presentera indikerar på att organisationer måste skapa tydliga riktlinjer hur ANSI/EIA-748 skall tillämpas. Till exempel att alla bryter ner arbetet och fördelar sina budgetar på samma sätt. Studiens resultat antyder också att Rolling Wave är ett lämpligt verktyg för komplexa och långa projekt. Av den anledningen att projektledare inte planerar för mycket i onödan eftersom projektets omfattning ständigt förändras.

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Henttu-Aho, T. (Tiina). "The emerging practices of modern budgeting and the role of controller." Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526214399.

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Abstract The presumed dominance of the traditional annual budgeting process as a cornerstone of management control has been called into question in recent years. Various new developments in budgeting have been seen replacing or complementing organisations’ conventional budgeting. The dissertation provides a comprehensive picture of these new budgetary practices and their implications for management accounting work, through investigation of the fragmentation among various purposes of budgeting and of the ways in which the role of controller and new budgetary practices can complement each other. The dissertation is composed of four inter-related essays, which provide qualitative evidence of how firmly established practices such as budgeting change and what implications the change has for the conflicting purposes of budgeting. It also provides insight into the ways controllers are able to build holistic view of the totality of budgetary control and compile new accounting information. The empirical findings presented in the dissertation give rise to novel concept of fragmentation, which can be defined as an arrangement wherein a new mix of diverse controls is used to serve several purposes of budgeting and a single budgeting process is either replaced with or complemented by other control mechanisms. Fragmentation can serve as a common denominator for recent developments in budgeting but also aid in understanding the variation in new budgetary practices. Fragmentation of budgeting makes the boundaries of a budgetary system blurred but also enables designing flexibility into the control system itself. For the role of controller, fragmented budgetary practices mean co-ordinating the linkages between various budget-related methods, wider communication and interaction with organisational actors, new business-oriented skills related to key purposes of budgeting, and a growing professional role in increasing the ‘realism’ of accounting information in the lateral budgetary planning process
Tiivistelmä Perinteisen vuosibudjetoinnin valta-asemaa johdon ohjausjärjestelmien kulmakivenä on alettu kyseenalaistaa viime vuosina. Budjetoinnin uudet kehityssuuntaukset näyttäisivät joko korvaavan tai täydentävän vakiintunutta budjetointikäytäntöä organisaatioissa. Tämä väitöskirja tarjoaa kokonaisvaltaisen kuvan uusista käytännöistä, sekä niiden vaikutuksista johdon laskentatoimen työhön. Väitöskirja tutkii budjetoinnin eri tehtävien pirstaloitumista sekä sitä, miten controllerin rooli ja uudet budjetointikäytännöt voivat toimia toisiaan täydentävästi. Väitöskirja muodostuu neljästä toisiinsa liittyvästä esseestä, jotka tuovat laadullisen tutkimuksen keinoin esille, kuinka vakiintunut käytäntö, kuten budjetointi, muuttuu, ja mitä vaikutuksia tällä muutoksella on budjetoinnin eri tehtäviin. Tutkimus tarjoaa myös käsityksen siitä, miten kontrollerit muodostavat kokonaiskuvan budjetoinnillisesta ohjausjärjestelmästä ja tuottavat uutta laskentatoimen informaatiota. Tämä väitöskirja kuvaa budjetoinnin muutosta käsitteellä pirstaloituminen (fragmentation). Se voidaan määritellä järjestelyksi, jossa uutta, erilaisten ohjausmenetelmien yhdistelmää käytetään palvelemaan budjetoinnin eri tehtäviä, ja jossa yksittäinen budjetointiprosessi joko korvautuu tai täydentyy muilla ohjausmekanismeilla. Tämä käsite tarjoaa yhteisen nimittäjän viimeaikaisille budjetoinnin kehityssuuntauksille, mutta auttaa myös ymmärtämään paremmin budjetoinnin eri variaatioita. Budjetoinnin pirstaloituminen hämärtää budjetointijärjestelmän rajat, mutta mahdollistaa myös joustavuuden suunnittelun järjestelmään itsessään. Kontrollerin roolin näkökulmasta budjetoinnin pirstaloituminen merkitsee budjetoinnin eri menetelmien välisten yhteyksien koordinointia, laajempaa kommunikaatiota ja vuorovaikutusta organisaation eri toimijoiden kanssa, uusien liiketoimintaorientoituneiden taitojen lisääntymistä sekä ammatillisen roolin korostumista laskentainformaation realismin parantamisessa budjetoinnin lateraalisessa suunnitteluprosessissa

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Голоскокова, Анна Олександрівна. "Моделі та інформаційна технологія планування покращення якості процесу розробки програмного забезпечення." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/38718.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13.06 – інформаційні технології. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. У дисертаційній роботі вирішено важливу науково-практичну задачу підвищення якості процесу розробки програмного забезпечення на основі моделі зрілості CMMІ з використанням ковзного планування. Виконано аналіз сучасного стану проблем підвищення якості ПР ПЗ. З урахуванням наведених проблем поставлено задачу розробки методу планування покращення якості ПР ПЗ, який базується на ковзному плануванні і дозволяє за рахунок спрощеної динамічної моделі зменшити розмірність задачі, а за рахунок статичної моделі підвищити точність результату. Для підвищення швидкості роботи алгоритму "Київський віник", який відноситься до методу послідовного аналізу варіантів, удосконалено технологію спрямованого перебору варіантів на кожному його етапі за рахунок вирішення множини оптимізаційних задач булевого програмування. На основі розробленого методу, моделей та алгоритмів реалізовано інформаційну технологію СППР, для якої було обрано архітектуру програної системи типу трирівневий "клієнт-сервер" з виділеним сервером застосунків. Результати досліджень впроваджено в практику функціонування ІТ-компаній м. Харкова, а також у навчальний процес кафедри програмної інженерії та інформаційних технологій управління НТУ "ХПІ".
The dissertation for a candidate degree in technical sciences, specialty 05.13.06 – Information Technologies. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2018. In the dissertation the important scientific and practical task for the quality improvement of the software development process is solved based on the maturity model Capability Maturity Model Integration (CMMI) using the rolling planning. The analysis of the current problems in the quality improvement of the software development process has been done. Taking into account analyzed issues, the problem of the method development for the quality improvement of the software development process has been set. The method is based on the rolling planning and allows reducing the dimensionality of the task by the dynamic model simplification, and increasing the accuracy of the result due to the static model. In order to increase the speed of "Kiev broom" algorithm, which is related to the method of the sequential analysis of the alternatives, the technology of oriented search of the alternatives at each algorithm’s stage has been improved by solving the set of optimization problems of Boolean programming. Based on the developed method, models and algorithms, the information technology for the decision support system (DSS) has been implemented. DSS has the architecture of the software system of three-level "client-server" type with a dedicated application server. Research results were introduced into the practical activities of IT companies in Kharkiv, as well as in the educational process at the Software engineering and management information technology department of NTU "KhPI".

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Голоскокова, Анна Олександрівна. "Моделі та інформаційна технологія планування покращення якості процесу розробки програмного забезпечення." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/38692.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.13.06 – інформаційні технології. – Національний технічний університет "Харківський політехнічний інститут", Харків, 2018. У дисертаційній роботі вирішено важливу науково-практичну задачу підвищення якості процесу розробки програмного забезпечення на основі моделі зрілості CMMІ з використанням ковзного планування. Виконано аналіз сучасного стану проблем підвищення якості ПР ПЗ. З урахуванням наведених проблем поставлено задачу розробки методу планування покращення якості ПР ПЗ, який базується на ковзному плануванні і дозволяє за рахунок спрощеної динамічної моделі зменшити розмірність задачі, а за рахунок статичної моделі підвищити точність результату. Для підвищення швидкості роботи алгоритму "Київський віник", який відноситься до методу послідовного аналізу варіантів, удосконалено технологію спрямованого перебору варіантів на кожному його етапі за рахунок вирішення множини оптимізаційних задач булевого програмування. На основі розробленого методу, моделей та алгоритмів реалізовано інформаційну технологію СППР, для якої було обрано архітектуру програної системи типу трирівневий "клієнт-сервер" з виділеним сервером застосунків. Результати досліджень впроваджено в практику функціонування ІТ-компаній м. Харкова, а також у навчальний процес кафедри програмної інженерії та інформаційних технологій управління НТУ "ХПІ".
The dissertation for a candidate degree in technical sciences, specialty 05.13.06 – Information Technologies. – National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2018. In the dissertation the important scientific and practical task for the quality improvement of the software development process is solved based on the maturity model Capability Maturity Model Integration (CMMI) using the rolling planning. The analysis of the current problems in the quality improvement of the software development process has been done. Taking into account analyzed issues, the problem of the method development for the quality improvement of the software development process has been set. The method is based on the rolling planning and allows reducing the dimensionality of the task by the dynamic model simplification, and increasing the accuracy of the result due to the static model. In order to increase the speed of "Kiev broom" algorithm, which is related to the method of the sequential analysis of the alternatives, the technology of oriented search of the alternatives at each algorithm’s stage has been improved by solving the set of optimization problems of Boolean programming. Based on the developed method, models and algorithms, the information technology for the decision support system (DSS) has been implemented. DSS has the architecture of the software system of three-level "client-server" type with a dedicated application server. Research results were introduced into the practical activities of IT companies in Kharkiv, as well as in the educational process at the Software engineering and management information technology department of NTU "KhPI".

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Lucas, Rémi. "Planification adaptative des ressources ferroviaires." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. https://theses.hal.science/tel-03009036.

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La planification ferroviaire consiste à établir en amont des circulations un plan de transport spécifiant l’emploi du temps de chaque ressource : les sillons, qui correspondent aux horaires des trains, les matériels roulants devant assurer leur circulation, ainsi que les agents à bord de ces trains. Compte tenu de la complexité du système ferroviaire, cette planification est effectuée potentiellement plusieurs années à l’avance, où un plan de transport précis est établi.Or, une fois qu’une ressource a été planifiée, il est parfois nécessaire d’adapter le plan de transport et donc de le changer. Les raisons peuvent être multiples : changement horaire pour causes de travaux, infrastructure partiellement endommagée, demande d’une rame supplémentaire pour un train, avarie sur un type de matériel roulant… Ainsi, le plan de transport est parfois adapté à plusieurs reprises entre sa conception potentiellement plusieurs années à l’avance et son exécution le jour des circulations. Dès lors, il est légitime de se demander si la conception d’un plan de transport précis avec des échelles de temps aussi importantes est raisonnable.Dans cette thèse, nous envisageons d’ajouter de la flexibilité dans le processus de planification, afin que les efforts déployés pour adapter le plan de transport lorsque cela est nécessaire soient réduits. Nous introduisons la notion de coûts d’adaptation du plan de transport, et nous proposons d’expliciter ces coûts d’adaptation pour le matériel roulant. Nous précisons notamment les coûts d’adaptation structurels, qui permettent de quantifier les similitudes entre deux planifications différentes du matériel roulant. La planification adaptative telle que nous l'envisageons consiste alors à anticiper dès la phase de conception les futures adaptations possibles du plan de transport. Plusieurs modèles de Programmation Linéaire en Nombres Entiers sont introduits et des résultats expérimentaux sont proposés sur des instances réelles issues de SNCF. L'approche de planification adaptative a pu être comparée à l'approche actuelle, et on montre que les coûts d'adaptation du plan de transport peuvent être effectivement réduits en adoptant cette nouvelle façon de planifier
Railway planning consists of drawing up a transportation plan before operational time, specifying a planning for each resource: the train paths, which correspond to the schedules, the rolling stock that will be used to move the trains, and the crew on board the trains. Given the complexity of the railway system, this transportation plan is carried out potentially several years in advance, when a precise transportation plan is drawn up.However, once a resource has been planned, it is sometimes necessary to adapt the transportation plan and therefore change it. There may be many reasons for this: schedule changes due to work, partially damaged infrastructure, request for an additional train set for a train, damage to a type of rolling stock, etc. Thus, the transportation plan may sometimes be adapted several times between its design, potentially several years in advance, and its execution on the day of traffic. It is therefore legitimate to ask whether the design of a precise transport plan with such large time scales is reasonable.In this thesis, we consider the adding of flexibility to the planning process so that the effort to adapt the transportation plan when necessary is reduced. We introduce the notion of transportation plan adaptation costs, and we propose to make these adaptation costs explicit for the rolling stock resource. In particular, we specify the structural adaptation costs, which make it possible to quantify the similarities between two different rolling stock plannings. Adaptive planning consists in anticipating possible future adaptations of the transport plan as early as the design phase. Several Integer Linear Programs are introduced and experimental results are proposed on real SNCF instances. The adaptive planning approach can be compared with the current approach, and it is shown that the adaptation costs can be effectively reduced by adopting this new way of planning

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Nguyen, Phuong Loan. "Planification tactique de la production : approche hiérarchisée pour une classe d'entreprises de sous-traitance et application au cas d'une entreprise de laminage à froid." Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10072.

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Dans cette these, nous considerons le probleme de la planification de la production pour une classe d'entreprises de sous-traitance. Celles-ci peuvent avoir une clientele tres diversifiee, ce qui implique notamment une grande variete des produits fabriques. Nous nous interessons en particulier au cas d'une entreprise de siderurgie, dont l'activite est le laminage a froid de feuillards d'acier. Etant donnee la complexite d'un tel probleme, nous avons envisage une approche hierarchisee, apres avoir defini des niveaux d'agregation sur les produits et sur les equipements. L'une des principales preoccupations de telles entreprises est de pouvoir proposer aux clients des delais competitifs, tout en s'assurant que ceux-ci puissent etre respectes. Pour cela, nous avons developpe un systeme d'aide a la decision base sur trois niveaux. Le premier niveau sert de support pour gerer de maniere dynamique l'arrivee de nouvelles commandes sur un horizon long terme, tout en effectuant une planification au niveau de l'usine. A partir des resultats obtenus, un deuxieme niveau verifie la faisabilite du plan de production en tenant compte des capacites des ateliers. Pour ce niveau plusieurs modeles adaptes a la classe d'entreprises consideree sont presentes. Enfin, le niveau inferieur a pour but d'assurer la coherence entre le plan prevu et le deroulement reel dans le systeme de production, en agissant sur les lancements en fabrication. Pour ce dernier module, nous presentons une approche heuristique specifique au cas particulier etudie, en prenant en compte des contraintes fortes du processus de fabrication, et nous proposons une generalisation possible de la methode pour d'autres entreprises de sous-traitance.

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14

Liu, Kuo-Chu, and 劉國著. "Development of Optimization Model for Rolling Stock Utilization Planning." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/23033256402487037453.

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碩士
國立臺灣大學
土木工程學研究所
100
Rolling stock is one of the most expensive assets of a railway agency or company. Therefore, efficient utilization of rolling stock is a very important objective pursued in practice. This study proposed a Rolling Stock Utilization Planning Tool to improve the efficiency of rolling stock usage by creating a utilization schedule to cover the trips in the timetable with the consideration of practical requirements, such as inspection regulation, depot capacity, rolling stock characteristics, and most important of all, the idea of schedule circulation. Past studies usually simplified the problem by ignoring some of the important factors in practices; therefore, most of the railway agencies or companies still rely on experienced planners for this task. These practitioners can generally create an acceptable plan but there is no guarantee of the optimality. Consequently, there is a need for a planning tool which takes all important factors into account and provides optimal solutions to this problem. In order to develop such tool, this research first identified the appropriate factors by reviewing literatures and interviews with practitoners. Then the Rolling Stock Utilization Planning Model is developed to minimize the deadhead cost and inspection cost in rolling stock utilization planning cycle. This study also presents the column generation method with Gilmore-Gomory algorithm to improve the solution efficiency, especially for large-scale problem. The practical cases of Taiwan Railways Administration were used to demonstrate the validity and applicability of the proposed tool. The empirical results show that this optimization process can produce more efficient utilization plans with minimal deadhead distance and significant reduced number of inspections compared to the manual process. It’s equivalent to successfully reduce the total deadhead and inspection cost by 20%~25%. Using this decision support tool will help railways improve the efficiency of rolling stock utilization so as to provide reliable service to their customers.

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Tsao, Chia-Hsin, and 曹家馨. "A Study of Rolling Stock Maintenance System Planning of TaoYuan International Airport MRT." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/00259858705231574643.

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碩士
國立交通大學
管理學院碩士在職專班運輸物流組
97
It’s the interantioal railway transportation trend in decades; the railway transportation system provides the passengers delivery service from airport area access to the main city area. The airport express is mainly provide the international business traveller a reliable transportation service to access from/to the airport area, such as Japan Narita Express, Hongkong airport express, etc. The airport express is basically using the unique railway access right and will not be affected by the roadway traffic. Taiwan government had approved the TTY International Access MRT system development project after many years schedulded and planed. Based on the above study background and motivation, the purpose of this study is considered and planed according to the TTY International Access MRT EMU maintenance system. To realize the planning of the EMU maintenance requirement model so that the EMU maintenance requirement estimated model will be the basis for the relevant EMU maintenance facilities and equipment to be allocated in the depot.

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林志鴻. "The material planning model of component commonality using rolling schedules in assembly industries." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/28443051219065846528.

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17

Lin, Chun-Yen, and 林軍諺. "Applying Rolling Schedule on Multi-Period, Multi- Product Production Planning Considering of Safety Stock." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/43943619822213103037.

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碩士
國立臺灣大學
商學研究所
103
Cost management is important to generate higher profit for companies in intense competitive environments. Inventory management is especially vital for manufacturers, and a good inventory policy will not only influence cost but also customer service. While customer service levels will rise, it will also cause huge management costs. However, less inventory will easily generate a higher probability of backlog. Production planning provides factories a method to effectively plan the production units under limited capacity and meanwhile calculate the best inventory level each period to minimize total costs. In the past study of production planning, demand levels are provided and most of them consider the possibility of shortage. For example, a food company is examined in this study, where future demand forecasting is based on real sales data with a rolling schedule applied to the model. Besides this, to lower the probability of shortages, while establishing a model of production planning we consider the importance of safety stock, design two-stage penalty mechanism, basic penalty cost and extra penalty cost. Considering different cost items in this study, we implement the model and analyze the impact by sensitive analysis as well, and conclude as following paragraph: 1. Under a two-stage penalty mechanism, factories can effectively plan production schedule and make better decisions based on tradeoffs between holding inventory and backlog. 2. With the increase of safety stock, total cost and basic penalty costs will rise at an increasing rate. However, safety stock has no influence on backlog. 3. The adjustment of service level only has a minor impact on total costs. While the service rate moved from 75% to 85%, it shows a great improvement on backlog, but no further changes happen if the rate advances to 95%. 4. With the rise of basic penalty cost, both total cost and holding cost will increase, but total cost increase at a decreasing rate. On the other hand, change of basic penalty cost has no relation to backlog.

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Cowling, Peter I. "A Flexible Decision Support System for Steel Hot Rolling Mill Scheduling." 2003. http://hdl.handle.net/10454/3193.

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No
A steel hot rolling mill subjects steel slabs to high temperatures and pressures in order to form steel coils. We describe the scheduling problem for a steel hot rolling mill. We detail the operation of a commercial decision support system which provides semi-automatic schedules, comparing its operation with existing, manual planning procedures. This commercial system is currently in use in several steel mills worldwide. The system features a very detailed multiobjective model of the steel hot rolling process. This model is solved using a variety of bespoke local and Tabu search heuristics. We describe both this model and the heuristics used to solve it. The production environment is highly unstable with frequent, unforeseen events interrupting planned production. We describe how the scheduling system's models, algorithms and interfaces have been developed to handle this instability. We consider particularly the impact on existing planning and production systems and the qualitative improvements which result from the system's implementation.

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Huang, Po-wen, and 黃柏文. "Development of Decision Support Framework and Models for Synchronized Resource Planning on Railway Route and Rolling Stock Upgrade." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/05715805213381126559.

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碩士
國立臺灣大學
土木工程學研究所
100
The most common, near-term approach to upgrading railway corridors to achieve high speeds is by incremental improvement. Existing infrastructure or rolling stock can be improved in various ways to allow for increasing speeds and reducing travel time along a route. Each track section has a characteristic set of opportunities for increasing speed and their corresponding effect on travel time reduction, along with an associated set of costs. Similarly, each type of rolling stock has the potential to increase operational speed and reduce travel time, corresponding to a specific price tag. This research focuses on developing a decision support process using mathematical programming to identify the most cost-effective strategy for reducing corridor travel time given a prescribed performance goal and budget. This optimization process was implemented in a railway corridor in Taiwan, and the result shows that the best strategy is a combination of infrastructure upgrade and rolling stock acquisition. Using this tool can help states and railway agencies simultaneously maximize capital investment returns and maintain reliable services for their customers.

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Li, Tzu-chin, and 李志欽. "A Study of the Optimal Production Planning and Product Mix Problems for Hot Rolling Wire Rods and Deformed Bars Mill in a Steel Plant." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/31244162572531813296.

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碩士
國立中正大學
企業管理所
97
The steel industry is the foundation of all industries, it is the basic industry of the national construction and the national defense industry, and it has also being called the mother of industries. Due to the consideration of economic development and security reason of the national defence, the governments of most countries often taking high tariff, quota to limit or classifying as the specific project of importing etc., in order to protect the development of the national steel industry. The production facilities, equipments, raw materials and energy consumptions are all more costly than the general industries. Thus, the steel industries are highly capital and skill intensive. The steel industry in Taiwan has been through and strived for half a century. Nowadays, the complete foundation of the steel industry in Taiwan has been established and proceeds to grow up. However, the breakout of the global financial crisis last year causes the sudden stagnation for the demand of the steel-made products, and brings the severe crisis ever for the steel industry. In addition, the drastic fluctuation of the international petroleum price also causes the production costs to go up as well as the prices of a variety of energy and raw materials. Under the severe environment today, the profits in the steel industries have being shrinked. That forces the managers in this industry to take steps to deal with this situation. In addition to making great efforts to develop the new products, to increase the profit margins, and to maintain basic and smooth operations of produciton lines and the prerequisite in the scale of economy, managers can’t help but make more cost-effective decisions. Among these decision problems, the optimal productin planning problem and product mix problem are two of the most crucial problems to the steel industry. Thus, the objective of this research is to develop the mathematical programming models to cope with these two decision problems. By considering the hot-rolled line of wire rods and reforming bars material for real industry production, we take various kinds of limiting conditions under the realistic environment into the mathematical programming models, and obtain the best production planning and the optimal product mix for the case steel firm so that the corporate''s minimum total production costs and the best profit-making level can be achieved.

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Alves, Cátia Filipa Veiga. "Desenvolvimento de um modelo de gestão em tempo real para empresas virtuais." Master's thesis, 2011. http://hdl.handle.net/1822/16422.

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Dissertação de mestrado integrado em Engenharia e Gestão Industrial
Hoje em dia tem-se a perceção do crescimento das empresas como um fator importante no desenvolvimento da economia. Como tal, Associações e Projetos têm vindo a desenvolver projetos traçados para o que as empresas necessitam, apontando para a crescente aposta em sistemas de gestão em tempo real. Nesse sentido nesta dissertação é proposta a investigação sobre o desenvolvimento de um modelo de gestão em tempo real para empresas virtuais (empresas em rede), com vista a redução do tempo de resposta ao mercado. Além deste modelo, e devido à importância do tempo de reconfiguração na crescente necessidade de alinhamento de negócio das empresas, desenvolveu-se uma estrutura para o tempo de reconfiguração e integração, onde se melhorou o modelo de estrutura do tempo de integração, introduzindo o tempo de transporte entre recursos. Com a construção e a validação do modelo de gestão em tempo real verificou-se a necessidade das empresas conseguirem mudar de recursos quase em tempo real, a cada momento de reconfiguração. No contexto de rede de empresas, estas devem ser essencialmente pequenas empresas devido aos seus baixos custos fixos. A dissertação apresenta contribuição original para a literatura através (1) do desenvolvimento de um modelo de gestão em tempo real onde o processo de gestão em tempo real é realizado através de um modelo teórico, e (2) do desenvolvimento de uma estrutura para o tempo de integração através da construção e preenchimento de novas visões sobre as arquiteturas de integração. Desta dissertação surge ainda a necessidade de trabalho futuro em campo empresarial que certamente irá trazer uma mais-valia para as empresas em rede, com o objetivo de as tornar mais cooperantes entre si, de modo a satisfazer objetivamente os seus clientes e reduzir o consumo de energia, como por exemplo, nos serviços de transporte.
The growth of enterprises is seen as a relevant economic development factor in nowadays. Aligning with the contemporary and emergent enterprises needs, the main company‘s investments and projects focus goes towards the real time management systems. Considering this and in order to make more agile and to minimize the time-to-market reaction, the development of a new model of real time management on virtual enterprises is proposed in the adjacent work of this thesis. The emergent need to be quickly aligned with the continuous changes on global business paradigms and overcome the competition brought by the multiple potential stakeholders, the time to reconfigure and to face with the new requirements is critical. Since a new structure for reconfiguration and integration times that considers the transport time between resources was developed and a better integration time structured was archived. After the proposed real time management model validation, the enterprises needs for real time resources change in their reconfiguration process, became evident. Furthermore, in a networked enterprises context these companies need to be essentially small enterprises due to their lower fixed costs. This thesis presents an innovative scientific contribution to real time systems since it follows a theoretical model. It develops an integration time structure through the construction and fulfilment of new visions about integration architectures, as well. From this thesis appears the need of future work in the industry that will bring an added value to the networked enterprise, in order to make them more co-operative to achieve the client‘s needs and reduce energy consumption.

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Gemieux, Géraldine. "Planification de la récolte et allocation des produits aux usines." Thèse, 2009. http://hdl.handle.net/1866/3515.

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L’industrie forestière est un secteur qui, même s’il est en déclin, se trouve au cœur du débat sur la mondialisation et le développement durable. Pour de nombreux pays tels que le Canada, la Suède et le Chili, les objectifs sont de maintenir un secteur florissant sans nuire à l’environnement et en réalisant le caractère fini des ressources. Il devient important d’être compétitif et d’exploiter de manière efficace les territoires forestiers, de la récolte jusqu’à la fabrication des produits aux usines, en passant par le transport, dont les coûts augmentent rapidement. L’objectif de ce mémoire est de développer un modèle de planification tactique/opérationnelle qui permet d’ordonnancer les activités pour une année de récolte de façon à satisfaire les demandes des usines, sans perdre de vue le transport des quantités récoltées et la gestion des inventaires en usine. L’année se divise en 26 périodes de deux semaines. Nous cherchons à obtenir les horaires et l’affectation des équipes de récolte aux blocs de coupe pour une année. Le modèle mathématique développé est un problème linéaire mixte en nombres entiers dont la structure est basée sur chaque étape de la chaine d’approvisionnement forestière. Nous choisissons de le résoudre par une méthode exacte, le branch-and-bound. Nous avons pu évaluer combien la résolution directe de notre problème de planification était difficile pour les instances avec un grand nombre de périodes. Cependant l’approche des horizons roulants s’est avérée fructueuse. Grâce à elle en une journée, il est possible de planifier les activités de récolte des blocs pour l’année entière (26 périodes).
Forest industry is a sector located at the heart of the debate on globalisation and sustainable development, even if it is in decline. For many countries like Canada, Sweden and Chile, the objectives are to maintain a flourishing sector without damaging the environment and to realize the finite nature of resources. It is important to be competitive and to operate effectively on forest territories, from harvesting to manufacturing products, through transport, in a context where costs increase rapidly. This master’s thesis is developing a tactical operational planning model to organize activities for a year to meet requests for factories, without losing sight of the transport of harvested quantities and inventory management factory. The year is divided into 26 periods of two weeks. We seek harvest teams schedules and assignment to harvest areas (units) for a year. The problem is formulated as a mixed integer programming model, whose structure is based on each stage of the forest supply chain. We choose to solve it by an exact method, branch-and-bound. We were able to assess how the direct resolution of our planning problem was difficult for instances with a large number of periods. However the rolling horizon approach has proved successful. In a day, we obtained the harvest activities planning for 26 periods.

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23

Gémieux, Géraldine. "Modèles et méthodes pour la planification de la récolte forestière." Thèse, 2015. http://hdl.handle.net/1866/13712.

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Ce projet de recherche a été réalisé avec la collaboration de FPInnovations. Une part des travaux concernant le problème de récolte chilien a été effectuée à l'Instituto Sistemas Complejos de Ingeniería (ISCI) à Santiago (Chili).
La planification de la récolte forestière comporte différents niveaux de planification selon l'horizon de temps du problème et la nature des décisions à prendre. Dans un premier temps, nous nous intéressons à un problème de planification annuelle de la récolte, à mi-chemin entre la planification tactique et opérationnelle. Ce problème appliqué à l'exploitation forestière au Québec, naît d'un besoin de l'industrie québécoise d'un outil pour la planification annuelle intégrée qui fournit aux équipes de récolte leur calendrier. L'intégration consiste à déterminer les affectations des équipes aux blocs en fonction des besoins des usines, et qui respectent les contraintes de transport, de gestion des stocks, et bien entendu les conditions d'exploitation en forêt. Plusieurs modèles de types MIP ont été formulés, des approches de résolution adaptées à la structure de chacun des modèles ont été développées. L'approche par horizon roulant est celle dont les résultats surpassent les deux autres et surtout, améliorent de façon significative les plans usuellement suivis, notamment en réduisant les volumes non livrés aux usines de moitié, ou encore en divisant entre 2 et 6 fois les volumes en stock quand la demande diminue. De plus, le développement d'une interface pour systématiser le processus de résolution et élargir le nombre d'utilisateurs, est la seconde contribution de la thèse. Cette étape du projet correspond à un transfert de technologie de l'université vers l'industrie. Le second problème de planification se situe au Chili, est une planification tactique de la récolte dirigée par les prix et demandes en produits finis, ces derniers étant considérés comme des paramètres aléatoires. Le problème stochastique formulé est résolu suivant une méthode de décomposition par scénarios dont le nombre varie entre 10 et 100. Pour chaque scénario, la solution déterministe, lorsqu'elle est réalisable, est comparée avec celle issue de la résolution du problème stochastique. La solution déterministe n'est réalisable que pour une dizaine de scénarios parmi 100, et les pertes encourues sont en moyenne de 9%.
Harvest planning has different levels according to the time horizon of the problem and the nature of the decisions to be taken. Initially, we are interested in an annual harvest scheduling problem, halfway between tactical and operational planning. This problem applied in Qu\'ebec, is motivated by a need from the industry for an integrated tool that provides annual schedules to harvest teams. The integration is to determine demand driven assignments of teams to cutblocks and to manage transportation and inventory accordingly. Several MIP models have been formulated, and three solution approaches have been developed according to the structure of each model. The rolling horizon approach performs better than the other two, by improving significantly from the traditional harvest plan, especially by reducing by half non delivered volumes or by dividing between 2 and 6 times volumes in storage when demands decrease. Another contribution of the thesis is the creation of an interface to systematize solution process and to allow other users. This is the object of a transfer project between academics and industry. The second problem is a Chilean tactical harvest planning. Harvesting decisions are driven by stochastic demands and prices of final products. The stochastic problem is solved using a heuristic based on a scenario decomposition technique. The number of scenarios considered is between 10 and 100 scenarios. For each scenario, when the deterministic solution is feasible, it is compared with the stochastic solution for the current scenario. The deterministic solution is only feasible for 10% of the scenarios, and induces losses of 9% in average.

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Dissertations / Theses on the topic 'Rolling planning'

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