Résumé Dissertation analysis raising of phenomenon of automobilism in the american city of Detroit in first half of 20. century. Analysis is focus primarily on the "Big Three" of car producers: Ford Motor Company, General Motors a Chrysler LLC. Analysis is temporalily delimitated with two moments, closely conected with developing of automobilism: Increase of popularity of cars at the begin of 20. century and Great depression. Important moments in delimitated time period were especially: founding of Ford Motor Company in 1903, founding of General Motors in 1908, implementation of assembly line by Henry Ford in 1913, founding of Chrysler LLC in 1925 and of course the Great Depresion from 1929. Special priority is focus on the personality od Henry Ford and his style of organization of work, company development and inovations, that were introduced mostly by his company, followed by others. Henry Ford has absolutely special position, mostly because of his complex care of his employes.Objective of this work is not only to analyze unprecedent increase and development of the city of Detroit, but also to describe demographical change of society, due by the development of automobile industry in the state of Michigan. Major question is: How the city of Detroit was changed in connection with industrial development,...

The global competitive environment and the growing demand for personalised products have increased the interest of companies in producing similar product models on the same assembly line. Companies are forced to make significant structural changes to rapidly respond to diversified demands and convert their existing single-model lines into mixed-model lines in order to avoid unnecessary new line construction cost for each new product model. Mixed-model assembly lines play a key role in increasing productivity without compromising quality for manufacturing enterprises. The literature is extensive on assembling small-sized products in an intermixed sequence and assembling large-sized products in large volumes on single-model lines. However, a mixed-model parallel two-sided line system, where two or more similar products or similar models of a large-sized product are assembled on each of the parallel two-sided lines in an intermixed sequence, has not been of interest to academia so far. Moreover, taking model sequencing problem into consideration on a mixed-model parallel two-sided line system is a novel research topic in this domain. Within this context, the problem of simultaneous balancing and sequencing of mixed-model parallel two-sided lines is defined and described using illustrative examples for the first time in the literature. The mathematical model of the problem is also developed to exhibit the main characteristics of the problem and to explore the logic underlying the algorithms developed. The benefits of utilising multi-line stations between two adjacent lines are discussed and numerical examples are provided. An agent-based ant colony optimisation algorithm (called ABACO) is developed to obtain a generic solution that conforms to any model sequence and it is enhanced step-by-step to increase the quality of the solutions obtained. Then, the algorithm is modified with the integration of a model sequencing procedure (where the modified version is called ABACO/S) to balance lines by tracking the product model changes on each workstation in a complex production environment where each of the parallel lines may a have different cycle time. Finally, a genetic algorithm based model sequencing mechanism is integrated to the algorithm to increase the robustness of the obtained solutions. Computational tests are performed using test cases to observe the performances of the developed algorithms. Statistical tests are conducted through obtained results and test results establish that balancing mixed-model parallel two-sided lines together has a significant effect on the sought performance measures (a weighted summation of line length and the number of workstations) in comparison with balancing those lines separately. Another important finding of the research is that considering model sequencing problem along with the line balancing problem helps algorithm find better line balances with better performance measures. The results also indicate that the developed ABACO and ABACO/S algorithms outperform other test heuristics commonly used in the literature in solving various line balancing problems; and integrating a genetic algorithm based model sequencing mechanism into ABACO/S helps the algorithm find better solutions with less amount of computational effort.

Si le problème d'équilibrage lors de la conception de lignes d'assemblage est largement étudié dans la littérature sous le nom d’ALBP (Assembly Line Balancing Problems), peu de travaux concernent leur rééquilibrage dans un horizon court terme et en-ligne. Les travaux présentés dans ce mémoire portent donc sur le rééquilibrage dynamique des lignes d’assemblage en réaction aux événements court terme perturbants la production. L’objectif étant de changer l’allocation des taches sur les postes de travail afin de lisser la charge induite par la perturbation. Le délai court sans arrêt de production étant plus important que l'optimalité de la solution, le temps de résolution rapide des méthodes de résolution approchées nous a intéressé. Deux approches ont été étudiées pour leur simplicité et leur nouveauté dans le domaine du ALBP : la méthode ILS (Iterated Local Search) et la recherche d’atteignabilité sur un réseau d’automates communicants. Cela nous a montré qu'elles peuvent répondre au besoin de réactivité imposé par notre problème mais qu’elles sont difficilement adaptables lorsque les leviers d’action pour rééquilibrer la ligne sont modifiés. Notre proposition pour répondre à ce besoin d’adaptabilité est une méthodologie de modélisation et de résolution des problèmes de rééquilibrage des lignes d’assemblage s’appuyant sur un réseau d’automates communicants et une recherche d’atteignabilité sur celui-ci. Pour assurer la généricité, la méthodologie est décomposée en deux niveaux d’abstraction : l'étude de la classe du problème ALBP considéré et al résolution du problème spécifique. Les travaux ont été validés sur des exemples industriels issus de la société Trane. / Assembly lines are flow-oriented production systems. They are still typical in industrial production systems despite the evolution from mass-production to more personalized and fluctuating production. In order to meet customer demand (quantity, time, etc.) and to reduce manufacturing costs, the lines must be well balanced. In other words, the products need to move from one workstation to another with the same pace, usually called takt time. This assembly line design problem is widely studied in the literature under the name of ALBP (Assembly Line Balancing Problems). Nonetheless, few studies concern the on-line reconfiguration and in particular, the dynamic rebalancing. The work presented in this thesis focuses on the dynamic rebalancing of assembly lines in response to short-term events disturbing production. Two approaches have been studied for their simplicity, speed of implementation and innovation in the field of ALBP: the ILS approach (Iterated Local Search) and the reachability analysis approach based on a network of communicating automata. This study showed that both approaches can address the need for a quick resolution required by dynamic rebalancing problem but lacked for adaptation when model constraints or objectives are changed. A methodological approach for assembly line balancing problems modeling and resolution is proposed to bridge the gap of adaptability. To ensure the genericity of obtained models., the methodology is composed of two levels of abstraction: a study of the class of the considered problem and a focus on the specific problem to solve. Studies have been validated on industrial examples from Trane factories.

Existem muitos estudos e publicações focadas no planejamento e desenvolvimento de novos produtos. Porém, o mesmo não é notado em estudos relativos à implantação destes novos produtos e seus processos na área de manufatura. Para tal, é desenvolvido neste trabalho um modelo de referência consistente para a implantação de novos processos de montagem no setor automotivo. O citado modelo contém a descrição das etapas, as verificações de qualidade, as ações e as necessárias validações do produto produzido no processo de produção em série. O teste da consistência e relevância dessa metodologia ocorre por meio da aplicação do modelo proposto, no desenvolvimento de um processo da montagem de componentes na montagem final. Para a sua avaliação, compararam-se os indicadores de um processo existente em dois momentos: um primeiro, com o processo desenvolvido utilizando-se o método tradicional, e em segundo, com o desenvolvimento e implantação deste mesmo processo, utilizando-se o método proposto de desenvolvimento do processo produtivo, somado a uma avaliação qualitativa do modelo de referência, por meio de uma pesquisa, com especialistas reconhecidos do meio automotivo, validando-se assim o modelo proposto. / Currently, there are many studies and publications focused on the planning and development of new products. However, the same is not noted in studies related to the implementation of these new products and their processes in manufacturing area. For this, a consistent reference model is developed for implementation of new assembly processes in the automotive sector. This model contains a description of steps, quality checks, actions and validations required by the product manufactured in the serial production process. The test of consistency and relevance of this methodology occurs through the application of the proposed model, in the development of a process of component assembly in the final assembly. For its evaluation, the indicators of an existing process were compared in two time points: with the process developed using the traditional method, and secondly, with the development and implementation of this same process, using the proposed development method of the production process. This occurred alongside a qualitative evaluation of the reference model through a survey with recognized experts of the automotive environment, thus validating the proposed model.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-08-03T11:05:17Z No. of bitstreams: 2 Dissertação - Carlos Alexandre Xavier da Silva - 2017.pdf: 2190162 bytes, checksum: 7c5e13d2301a93a75a0e2d68e1b9a893 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-08-03T11:06:02Z (GMT) No. of bitstreams: 2 Dissertação - Carlos Alexandre Xavier da Silva - 2017.pdf: 2190162 bytes, checksum: 7c5e13d2301a93a75a0e2d68e1b9a893 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-08-03T11:06:02Z (GMT). No. of bitstreams: 2 Dissertação - Carlos Alexandre Xavier da Silva - 2017.pdf: 2190162 bytes, checksum: 7c5e13d2301a93a75a0e2d68e1b9a893 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In one version of the Simple Assembly Line Balancing Problem (SALBP) tasks are assigned to stations along an assembly line with a fixed cycle time in order to minimise the required number of stations. It is assumed that the total work needed for each product unit has been partitioned into economically indivisible tasks. In practice, it may be that the minimal number of stations can be reduced when it is possible to further divide particular tasks in limited ways even with additional time penalty costs. Allowing task division leads to a new assembly line balancing problem, TDALBP (Task Division Assembly Line Balancing Problem) and a solution procedure for it. This work introduces a mathematical model for the TDALBP and presents promising computational results for the adaptation of some classical SALBP instances from the research literature. The results demonstrate that the TDALBP has the potential to significantly improve assembly line performance. / O balanceamento eficaz de uma linha de produção é importante para aprimorar a produtividade e reduzir custos de uma industria. O problema do balanceamento de linhas de produção (Assembly Line Balancing Problem - ALBP) envolve atribuir as tarefas necessárias para produzir cada unidade de um produto entre estações de trabalho ao longo de uma linha de produção, a fim de otimizar alguma medida de desempenho do sistema. Tradicionalmente, supõe-se que o trabalho total necessário para cada unidade de produto foi particionado em tarefas economicamente indivisíveis, de modo que uma maior divisão gera custos desnecessários. Assim, cada tarefa requerida não pode ser dividida e deve ser realizada em uma única estação. Na prática, no entanto, isso pode não ser sempre verdadeiro quando existe um objetivo orientado ao tempo, tal como a minimização do número de estações para um determinado tempo de ciclo. Neste caso, pode ser que o número mínimo das estações possa ser reduzido quando for possível continuar a dividir tarefas particulares de formas limitadas, mesmo se a divisão induzir custos adicionais de tempo. A permissão de tal divisão de tarefas nos leva a um novo problema de balanceamento de linhas de produção, o qual denotamos por TDALBP (Task Division Assembly Line Balancing Problem). Nós propomos um modelo de programação linear inteira binária para o TDALBP e procedimentos efetivos para solucioná-lo. Os procedimentos foram avaliados sobre adaptações de várias instâncias SALBP clássicas da literatura. Os resultados computacionais são promissores e mostram o potencial do TDALBP para a melhora significativa do desempenho de linhas de produção.

In the present fierce global competition, poor responsiveness, low flexibility to meet the uncertainty of demand, and the low efficiency of traditional assembly lines are adequate motives to persuade manufacturers to adopt highly flexible production tools such as cross-trained workers who move along the assembly line while carrying out their planned jobs at different stations [1]. Cross-trained workers can be applied in various models in assembly lines. A novel model which taken into consideration in many industries nowadays is called the linear walking worker assembly line and employs workers who travel along the line and fully assemble the product from beginning to end [2]. However, these flexible assembly lines consistently endure imbalance in their stations which causes a significant loss in the efficiency of the lines. The operational time variability is one of the main sources of this imbalance [3] and is the focus of this study which investigated the possibility of decreasing the mentioned loss by arranging workers with different variability in a special order in walking worker assembly lines. The problem motivation comes from the literature of unbalanced lines which is focused on bowl phenomenon. Hillier and Boling [4] indicated that unbalancing a line in a bowl shape could reach the optimal production rate and called it bowl phenomenon.  This study chose a conceptual design proposed by a local automotive company as a case study and a discrete event simulation study as the research method to inspect the questions and hypotheses of this research.  The results showed an improvement of about 2.4% in the throughput due to arranging workers in a specific order, which is significant compared to the fixed line one which had 1 to 2 percent improvement. In addition, analysis of the results concluded that having the most improvement requires grouping all low skill workers together. However, the pattern of imbalance is significantly effective in this improvement concerning validity and magnitude.

This research investigates the problem of constrained sequencing of a set of jobs on a conveyor system with the objective of minimizing setup cost. A setup cost is associated with extra material, labor, or energy required due to the change of attributes in consecutive jobs at processing stations. A finite set of attributes is considered in this research. Sequencing is constrained by the availability of two elements ??orage buffers and conveyor junctions. The problem is motivated by the paint purge reduction problem at a major U.S. automotive manufacturer. First, a diverging junction with a sequence-independent setup cost and predefined attributes is modeled as an assignment problem and this model is extended by relaxing the initial assumptions in various ways. We also model the constrained sequencing problem with an off-line buffer and develop heuristics for efficiently getting a good quality solution by exploiting the special problem structure. Finally, we conduct sensitivity analysis using numerical experiments, explain the case study, and discuss the use of the simulation model as a supplementary tool for analyzing the constrained sequencing problem.

The unbundling of the faculty role occurs when e-learning course tasks normally performed by a single faculty member--such as course design, development, delivery, grading, interaction with students, course improvement, and advisement--are segmented or unbundled so that they can be performed by other personnel or with technologies. Using a qualitative methods approach, this study examines the unbundling and restructuring of the faculty professional role in large enrollment e-learning courses. This study was conducted at three community colleges in a large, urban community college district, and presents three models of e-learning course production that affect the unbundling of the faculty role: craft, collegial, and virtual assembly line. This research also examines how e-learning faculty members seek to rebundle tasks associated with their professional role and identity, and the tasks they perceive as meeting student needs and demand. This study contributes to professional and economic theories concerning faculty members in the e-learning context, and advances theories associated with academic labor, managed professionals, Academic Capitalism, and the globalization of the community college.

Purpose – The purpose of the study is to propose a framework for standardized workstations with focus on operators work activities and material presentation on a mixed-model assembly line. In order to fulfill the purpose, it was decomposed into three research questions: Research question 1: What problems in existing manual workstations can be identified, regarding work activities and material presentation? Research question 2: What can be considered regarding operators' work activities in creation of standardized workstations for a mixed-model assembly line? Research question 3: What can facilitate the work performance and ergonomics of operators when designing material presentation for standardized workstations for a mixed-model assembly line? Methodology – This study was carried out inductively through analysis of empirical data from a case study against existing theories from a literature study. Theories were in the areas of mixed-model assembly line, workstation design, material presentation, work activities, ergonomics and human aspect, and standardization and flexibility. To gather empirical data, a document study, observations and interviews were conducted at one case company. Findings – The study resulted in a framework for work activities and material presentation in standardized workstations on a mixed-model assembly line within the perspectives of ergonomics, standardization and non-value-added work. Results indicated on decreased efficiency if the involvement of human factor and standardization were insufficient in the workstation design, by increased non-value- added work and decreased ergonomics. Implications – The proposed framework intended to support companies to merge assembly lines into a mixed-model assembly line with low automation. Limitations – The framework in this study only focused on workstations' workactivities and material presentation. Workstations are linked to more than these two areas therefore should more areas be included in merging assembly lines. This framework had the perspectives of ergonomics, standardization and non-value-added work, more perspectives should be considered in a merger.

Submitted by MÁRCIO GARCIA RODRIGUES null (marciogarcia@maxionsc.com) on 2016-04-28T15:54:31Z No. of bitstreams: 1 Dissertacao_Marcio Garcia_280416.pdf: 2456536 bytes, checksum: b79ef40cb702a054ccb7d7f939704cf6 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-02T12:54:04Z (GMT) No. of bitstreams: 1 rodrigues_mg_me_guara.pdf: 2472389 bytes, checksum: 1c7d0b1b7f5b2d9c139a65d762cda63a (MD5) / Made available in DSpace on 2016-05-02T12:54:04Z (GMT). No. of bitstreams: 1 rodrigues_mg_me_guara.pdf: 2472389 bytes, checksum: 1c7d0b1b7f5b2d9c139a65d762cda63a (MD5) Previous issue date: 2016-04-21 / A crescente variedade de produtos nos sistemas atuais de produção é um grande desafio para a logística interna de abastecimento de materiais numa linha de montagem final, o abastecimento logístico precisa estar em concordância com a programação de produção de forma a disponibilizar para montagem o material necessário, no momento certo e na quantidade correta. A linha de montagem objeto do estudo acompanha esta tendência. Nela são montados modelos variados de chassis. Desta forma, o objetivo geral da pesquisa é desenvolver um modelo de abastecimento para linha de montagem multiprodutos, onde o ponto principal do trabalho é a definição do conceito mais adequado de acordo com o tipo e quantidade do material a ser abastecido. Através de uma pesquisa-ação foi proposto um modelo de abastecimento de linha que demonstrou uma redução de aproximadamente 50% da área ocupada na borda de linha, em consequência da redução de materiais, e aumento de 3% da produtividade, em virtude das reduções das indisponibilidades e perdas por set-up de abastecimento. / The increasing variety of products in current production systems is a big challenge for internal logistics supply of materials to a final assembly line, the logistic supply must be in step with the production program, in order to provide the necessary material for assembly at the right time and in the correct quantities. The assembly line which is the object of this study follows the trend. On it, several models of chassis are assembled. Therefore, the general objective of this research is to develop a supply model for a multi-product assembly line, with the main focus of the work on determining the most suitable concept in terms of the type and amount of material to be supplied. Through research-action, a model to supply the line has been proposed, which demonstrated a reduction of approximately 50% of the area occupied alongside the line, due to the reduction in materials, and an increase of 3% in productivity, owing to the reductions in outages and losses during supply set-up.