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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

On sustainability assessment of technical systems : experience from systems analysis with the ORWARE and ecoeffect tools

Assefa, Getachew January 2005 (has links)
Engineering research and development work is undergoing a reorientation from focusing on specific parts of different systems to a broader perspective of systems level, albeit at a slower pace. This reorientation should be further developed and enhanced with the aim of organizing and structuring our technical systems in meeting sustainability requirements in face of global ecological threats that have far-reaching social and economic implications, which can no longer be captured using conventional approach of research. Until a list of universally acceptable, clear, and measurable indicators of sustainable development is developed, the work with sustainability metrics should continue to evolve as a relative measure of ecological, economic, and social performance of human activities in general, and technical systems in particular. This work can be done by comparing the relative performance of alternative technologies of providing the same well-defined function or service; or by characterizing technologies that enjoy different levels of societal priorities using relevant performance indicators. In both cases, concepts and methods of industrial ecology play a vital role. This thesis is about the development and application of a systematic approach for the assessment of the performance of technical systems from the perspective of systems analysis, sustainability, sustainability assessment, and industrial ecology. The systematic approach developed and characterized in this thesis advocates for a simultaneous assessment of the ecological, economic, and social dimensions of performance of technologies in avoiding sub-optimization and problem shifting between dimensions. It gives a holistic picture by taking a life cycle perspective of all important aspects. The systematic assessment of technical systems provides an even-handed assessment resulting in a cumulative knowledge. A modular structure of the approach makes it flexible enough in terms of comparing a number of alternatives at the same time, and carrying out the assessment of the three dimensions independently. It should give way to transparent system where the level of quality of input data can be comprehended. The assessment approach should focus on a selected number of key input data, tested calculation procedures, and comprehensible result presentation. The challenge in developing and applying this approach is the complexity of method integration and information processing. The different parts to be included in the same platform come in with additional uncertainties hampering result interpretations. The hitherto tendency of promoting disciplinary lines will continue to challenge further developments of such interdisciplinary approaches. The thesis draws on the experience from ORWARE, a Swedish technology assessment tool applied in the assessment of waste management systems and energy systems; and from the EcoEffect tool used in the assessment of building properties; all assessed as components of a larger system. The thesis underlines the importance of sustainability considerations beginning from the research and development phase of technical systems. The core message of this thesis is that technical systems should be researched as indivisible parts of a complex whole that includes society and the natural environment. Results from such researches can then be transformed into design codes and specifications for use in the research and development, planning and structuring, and implementation and management of technical systems. / QC 20100505
112

Optimization of the Internal Logistics Served by an AGV System A case study at Kinnarps Production AB

Mishev, Grigor, Shahidi, Omid January 2008 (has links)
Logistics plays a crucial role in companies’ ability to sustain competitive on the market. Time is regarded as one of the important metric in terms of logistics, since time influences the lead time of the products, which results in the vital advantage of speed. The recent business environment forces Kinnarps Production AB, a manufacturer of furniture, to optimize their inventory material flow in a way of increasing their capability and capacity to load more distribution containers with goods daily. The present circumstances of the material flow are associated with number of negative factors. An automated guided vehicle (AGV) system is operating and handling the distribution of goods. Wrong sequence of activities, long transportations, high transportation delays, waiting time, varying numbers of AGVs, wastes, bottlenecks are among the important issues to be considered. The purpose of this thesis is to analyze the material flow in Kinnarps Production AB’s inventory seven and to improve the AGV system activities within. Concepts associated with identifying waste were used by separating value-adding activities from the non-value added ones. The usage of ideal reference systems techniques were the base for identifying problems. Concrete literature regarding AGV’s design system was applied in establishing different statements about the material flow and identification of problems. Different methods and techniques were used in approaching the research, but most above others is the case study approach. Numerous amounts of secondary data have been employed in verifying the collection of other data carried out by primary data collection as well as verifying the qualitative and quantitative analysis. A mapping of the current system was established with respect to orders, times and distances. Numbers of congestion points were identified, non-value adding activities were eliminated or decreased, rearrangement of sequencing of different activities was considered and different pallets arrangement system was established. A stochastic model was used in identifying the AGV’s time variables in the system and estimating appropriate amount of AGVs within the inventory. All the findings from different calculations and estimations were associated with Kinnarps Production’s future increased demand. Different issues and considerations were analyzed and appropriate suggestions were given for elimination of the negative factors in the inventory or their decrease. Among the most influencing results was the proper amount of AGVs in the inventory area, pallets rearrangement, different stocking policy, rearrangement in the sequence of activities, increase of the buffer for pallets used for loading containers, new conveyor system for the incoming goods in the inventory, transportation layout changes resulting in blocking free routines, separate control system, decrease of the effect of stoppages. All these findings are considered to optimize the material flow and increase the system capacity contributing to an increase of the daily containers outgoing from Kinnarps Production AB.
113

Material Flow Cost Versus Congestion In Dynamic Distributed Facility Layout Problem

Ozen, Aykut 01 July 2008 (has links) (PDF)
In this thesis, we study both dynamic and distributed facility layout problems, where the demand for product mix changes over time. We propose a new simulated annealing algorithm, SALAB, for the dynamic facility layout problem. Four variants of SALAB find the best known solution for 20 of the 48 benchmark problems from the literature, improving upon the best known solutions of 18 problems. We modify SALAB to obtain DSALAB, solving the dynamic distributed facility layout problem with the objective of minimizing relocation cost and total (full and empty) travel cost of the material handling system. We simulate DSALAB solutions of randomly generated problems to study the tradeoff between total cost and congestion in the system. Our experimental results indicate that distributing the department duplicates throughout the facility reduces the total cost with diminishing returns and causes increasing congestion. Therefore, distribution beyond a certain level is not justified.
114

Optimization of the Internal Logistics Served by an AGV System A case study at Kinnarps Production AB

Mishev, Grigor, Shahidi, Omid January 2008 (has links)
<p>Logistics plays a crucial role in companies’ ability to sustain competitive on the market. Time is regarded as one of the important metric in terms of logistics, since time influences the lead time of the products, which results in the vital advantage of speed. The recent business environment forces Kinnarps Production AB, a manufacturer of furniture, to optimize their inventory material flow in a way of increasing their capability and capacity to load more distribution containers with goods daily. The present circumstances of the material flow are associated with number of negative factors. An automated guided vehicle (AGV) system is operating and handling the distribution of goods. Wrong sequence of activities, long transportations, high transportation delays, waiting time, varying numbers of AGVs, wastes, bottlenecks are among the important issues to be considered.</p><p>The purpose of this thesis is to analyze the material flow in Kinnarps Production AB’s inventory seven and to improve the AGV system activities within.</p><p>Concepts associated with identifying waste were used by separating value-adding activities from the non-value added ones. The usage of ideal reference systems techniques were the base for identifying problems. Concrete literature regarding AGV’s design system was applied in establishing different statements about the material flow and identification of problems. Different methods and techniques were used in approaching the research, but most above others is the case study approach. Numerous amounts of secondary data have been employed in verifying the collection of other data carried out by primary data collection as well as verifying the qualitative and quantitative analysis.</p><p>A mapping of the current system was established with respect to orders, times and distances. Numbers of congestion points were identified, non-value adding activities were eliminated or decreased, rearrangement of sequencing of different activities was considered and different pallets arrangement system was established. A stochastic model was used in identifying the AGV’s time variables in the system and estimating appropriate amount of AGVs within the inventory.</p><p>All the findings from different calculations and estimations were associated with Kinnarps Production’s future increased demand. Different issues and considerations were analyzed and appropriate suggestions were given for elimination of the negative factors in the inventory or their decrease. Among the most influencing results was the proper amount of AGVs in the inventory area, pallets rearrangement, different stocking policy, rearrangement in the sequence of activities, increase of the buffer for pallets used for loading containers, new conveyor system for the incoming goods in the inventory, transportation layout changes resulting in blocking free routines, separate control system, decrease of the effect of stoppages. All these findings are considered to optimize the material flow and increase the system capacity contributing to an increase of the daily containers outgoing from Kinnarps Production AB.</p>
115

Optimalizace vybraného dodavatelského řetězce v rámci potravinářského sortimentu / Optimalization of the chosen supply chain in the range of food-processing assortment

KOS, Petr January 2010 (has links)
The aim of this thesis is the optimalization of chosen supplier chain from the point of view of material and informational flow, description of critical factors and a proposal for optimalization of the whole system from the point of view of logistic service and expenses. This thesis is devided into several parts. In the first part there are quoted some sources dealing with the topic of the thesis. In the second part present company functioning is described from the point of view of informational and material flow. These were analyzed within the conpany as well as between the company and the other parts of the chain. After evaluation of the results from the second part I tried to describe critical factors, which make the third part of the thesis. Ten critical factors were analyzed. The main part of the thesis is made by proposals for removing these critical factors.
116

Caracterização do consumo domestico de materiais da cidade de Montevidéu mediante análise de fluxos de materiais / Characterization of domestic materials consumption in Montevideo attending the analysis of material flows

Mimbacas Rodriguez, Alicia Filomena January 2012 (has links)
As cidades podem ser definidas como sistemas abertos altamente dependentes do seu entorno para a provisão dos recursos naturais e eliminação dos resíduos. Abarcando 2% da superfície da terra, elas consomem aproximadamente 75% de seus recursos, expulsando resíduos em escala similar. Na atualidade, 50% da população mundial habita em cidades e é estimado que esta porcentagem ascenderá a 70% no 2050. Em particular, a América Latina apresenta uma crescente população urbana. No ano 1970, 57 % da população era urbana e estima se que se atinja 81% no 2025. O Uruguai é o país de América Latina de maior porcentagem de população urbana: 93%, em 2010. A Análise de Fluxos de Materiais (AFM) é una metodologia de avaliação do campo da economia ecológica que tem sido pouco considerada na planificação ou gestão urbana regional. Argumenta-se que essas abordagens são as que podem dar luz a um modelo de desenvolvimento de cidades mais sustentáveis, contribuindo para a definição de políticas publicas ambientais. O objetivo do trabalho é estimar quantitativamente o consumo doméstico de materiais (CDM) para a cidade de Montevidéu, no período entre os anos 2002 e 2009. Os principais desafios do trabalho foram a inexistência de metodologias de consenso de aplicação regional e a dificuldade na aquisição de dados, os quais se encontram em sua maioria desagregados em diferentes instituições públicas e privadas. O referencial metodológico adotado foi o proposto por EUROSTAT, aplicado a nível nacional pelas maiores economias da OCDE. O trabalho propõe uma estratégia de ponderação que permite a passagem da escala nacional á urbana, Os resultados obtidos evidenciam um aumento no consumo de materiais em Montevidéu na serie de anos analisada, sendo 80% deles de origem não renovável no ano 2009. A indústria da construção é responsável por mais de 50% do consumo total. A estimação quantitativa do CDM, para a cidade de Montevidéu, é um primeiro passo na identificação de alternativas para uma menor intensidade no uso de materiais, condição indispensável para um relacionamento mais equilibrado entre os sistemas socioeconômicos e o médio ambiente. O CDM de Montevidéu é uma ferramenta em processo, passível de ser aprimorada em futuros trabalhos. A principal dificuldade deste trabalho foi a compatibilização dos diferentes critérios de classificação de materiais da metodologia da EUROSTAT e das bases de dados nacionais. / Cities can be defined as open systems that are highly dependent on their environment for the provision of natural resources and waste disposal. Although cities only cover 2% of the surface of the earth, they consume 75% of its resources. Currently, 50% of the world population lives in cities and it is estimated that this number will rise to 70% in the year 2050. This phenomenon is remarkable in Latin America. While in 1970 its urban population was 57%, it is expected to climb to 81% by 2025. In this context, Uruguay is the country of Latin America that present the higher rate of urban population: 93% (year 2010). The Material Flow Analysis (MFA) (an evaluation methodology from the field of ecological economics) has not been contemplated on regional planning and urban management. However, it is argued that these approaches can enlighten the development of more sustainable cities contributing to the definition of environmental public policy. The aim of this work is to quantify the domestic consumption of materials (fossils, minerals and biomass) for the city of Montevideo, Uruguay for the years 2006 and 2009. At this point, the main barriers are the lack of agreed on regional implementation methodologies and the difficulty with data acquisition. The methodological guide to be used is the one defined by Eurostat, applied nationally for several years by the greatest OECD economies. The paper proposes a weighting strategy that allows the passage from a national scale to an urban one.The results obtained for the period of time analized show an increase in consumption of materials and energy. For instance, the consumption of non-renewable sources reached 80% for the year of2009. On this period, the construction industry was responsible for the 50% of the total consumption. This diagnosis let us perceive the paths to follow in order to reduce the intensity of the use of materials and energy, wich is imperative to create a balanced relationship between socioeconomic systems and the environment. The DMC of Montevideo is a tool in the process, which can be improved in future works. The main difficulty of this work was to reconcile the different criteria of classification of materials from EUROSTAT methodology with national databases.
117

Systém řízení kvality v podniku a jeho zdokonalení / Quality management system and its improvement

PIVOVARSKÁ, Jitka January 2007 (has links)
These diploma thesis are oriented on a analysis of quality management system in Fezko a. s. Strakonice and propose possibilities for its improvement. Quality management system is in this company on high level. Company is certified according to ISO/TS 16949. The opportunities for system improvement were detected particularly in production control area and material flow. I propose using of modern quality management tools and implementing of lean manufacturing principles and Six Sigma methodology in production, including kaizen and kanban techniques.
118

Analýza logistického systému a jeho optimalizace ve firmě LIP distribution s.r.o. / Analyse of logistic system and its optimalization in LIP distribution s.r.o.

KUČERA, Kamil January 2008 (has links)
Analyse of logistic system and its optimalization of selected subject in light of material and information flow with concentration for logistic services and possibility of its optimalization.
119

Řízení materiálového toku na Zemědělské fakultě Jihočeské univerzity v Českých Budějovicích / Management of material flow in the Faculty of Agriculture at the University of South Bohemia in České Budějovice

DVOŘÁK, David January 2007 (has links)
The main target of this dissertation is logistic resource analysis in relation to expendable property with majority directing on reduction of total costs in the Faculty of Agriculture at the University of South Bohemia in České Budějovice by optimalization means of resource quotient fixed in inventories. Sub-target is availability detection of contemporary information system, eventually regulation or substitution by the new system, exact detection of real needs of faculty particular workplace in term of ordering system, supplies speed and assortment width {--} suggestion of system changes leading to the achievement of optimal supply version and spreading of offered assortment or offer cavity of particular lines of products. The result of this dissertation is suggestion of material flow assurance in the Faculty of Agriculture by the complex outsourcing system. On the basis of quotations confrontation and business conditions of potential providers was as the main provider suggested company Büroprofi, s.r.o.
120

Metabolismo de um município brasileiro de pequeno porte : o caso de Feliz, RS / Metabolism of a small Brazilian municipality : Feliz, RS, case study

Kuhn, Eugenia Aumond January 2014 (has links)
Estudos relacionados ao consumo de recursos e à emissão de resíduos na escala territorial local se originaram nas pioneiras pesquisas associadas ao conceito de metabolismo urbano. Nos últimos 15 anos, observa-se um crescimento do número de estudos aplicados a cidades, municípios ou regiões metropolitanas. A Análise dos Fluxos de Materiais - AFM (Material Flow Analysis) vem se consolidando como a abordagem metodológica predominante para esse tipo de investigação, a qual objetiva prover informações sobre fluxos de materiais e de energia, usualmente em unidades de massa, entrando e deixando uma sociedade. No entanto, todos os casos estudados na literatura prévia correspondem a capitais nacionais ou a municípios com centralidade econômica e de gestão do território na região as quais pertencem. Adicionalmente, não há estudos desenvolvidos no Brasil. Em face dessas lacunas, o objetivo principal deste trabalho é a caracterização dos fluxos de materiais associados ao metabolismo de um município brasileiro de pequeno porte (MBPP). Para tanto se adotou como estudo de caso o município de Feliz-RS. Como objetivos intermediários da pesquisa estabeleceram-se: a) Identificação dos métodos existentes para caracterização de fluxos de materiais na escala local e análise das possibilidades de aplicação no contexto dos MBPP; b) Desenvolvimento de um detalhamento metodológico da AFM, para a caracterização dos fluxos de materiais de MBPP; c) Análise das limitações e oportunidades para uso da AFM, na avaliação de sustentabilidade ambiental de municípios. Como resultados, avalia-se que o detalhamento metodológico desenvolvido é funcional e replicável para municípios brasileiros com o mesmo perfil, além de fornecer informações bastante detalhadas acerca dos fluxos ocorrentes no município adotado como caso. Assim, é possível realizar análises com diferentes níveis de desagregação. Quanto aos fluxos de materiais de Feliz, encontrou-se que o consumo doméstico de materiais per capita (DMC/ per capita) do município é alto, se comparado àqueles já caracterizados na literatura. Essa constatação corrobora com a proposição de que municípios com produção primária e secundária tendem a demandar, proporcionalmente, mais recursos do que aqueles que são consumidores finais. Quanto ao uso da AFM, na avaliação de sustentabilidade ambiental, verifica-se um alto potencial, com vantagens, em relação a outros métodos correntemente adotados. Entretanto, essas oportunidades ainda são pouco exploradas no contexto internacional e ignoradas no Brasil, ao se analisar a literatura existente. / Studies related to resources consumption and wastes emissions in a local territorial scale were originated from pioneering researches related to the urban metabolism concept. Over the past 15 years, there was a growth in the number of such studies applied to cities, municipalities and metropolitan areas. At the same time, Material Flow Analysis - MFA was consolidated as the predominant methodological approach for this type of research. However, it must be pointed out that all studied cases have been related to national capitals or counties, with economics centrality and land management in their own area. Besides, no studies of this nature were found as being developed in Brazil. Thus, the main goal of the research presented in this paper was to characterize material flows associated with the metabolism of a small Brazilian municipality and for this purpose the municipality of Feliz was adopted as a case study. Three intermediate objectives were established: a) To identify existing methods for material flows characterization on the local scale and to analyse the possibilities of applying them in the context of small Brazilian municipalities; b) to develop a MFA methodological detailing for the characterization of material flows of small Brazilian municipalities; c) to analyse constraints and opportunities for the use of MFA in the assessment of municipalities environmental sustainability. As results, it is considered that the methodological detailing developed raises the possibility of replicating the procedures applied in Feliz to other Brazilian municipalities, being this research a first and referential step in this direction. Besides, it provides very detailed information on flows occurring in the municipality adopted as the case study. Thus, it is possible ti further develop of analyses considering different levels of disaggregation. Concerning the material flows associated with the metabolism of Feliz, it was found that the studied municipality presents a DMC per capita comparable or superior to that of larger municipalities already analyzed by previous researches. This finding corroborates the hypothesis that municipalities with primary and secondary production tend to demand proportionately more resources than those who are the final consumers. Regarding the use of the MFA in the assessment of municipalities environmental sustainability, it was verified that it presents a high potential, with advantages over other methods currently adopted. However, when analyzing the existing literature it was noticed that these opportunities are still little explored in the international context and ignored in Brazil.

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