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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.
81

Modeling and Analysing Propagation Behavior in Complex Risk Network : A Decision Support System for Project Risk Management, / Modélisation et Analyse de Propagation dans un Réseau Complexe de Risques : Un système D’aide à la Décision Pour la Gestion des Risques Projet

Fang, Chao 02 December 2011 (has links)
La gestion des risques projet est une activité cruciale dans le management de projet. Aujourd'hui, les projets sont confrontés à une complexité croissante et sont ainsi exposés à de nombreux risques interdépendants. Cependant, les méthodes classiques ont des limites pour la modélisation de la complexité réelle des risques du projet. Par exemple, certains phénomènes comme les réactions en chaîne et des boucles ne sont pas correctement pris en compte. Cette thèse de doctorat vise à analyser le comportement du réseau de risques projet grâce à la modélisation des risques et des interactions entre risques. Un système d'aide à la décision est introduit avec une série de méthodes associées. La construction du réseau de risques projet nécessite l'implication du manager de projet et l'équipe d'experts en utilisant la méthode Design Structure Matrix (DSM). Des techniques basées sur la simulation et la théorie des réseaux sont développées pour analyser et hiérarchiser les risques du projet, en regard de leur rôle et leur importance dans le réseau des risques. L'approche proposée constitue un puissant complément à l'analyse classique des risques projet. Ces nouvelles analyses fournissent aux managers de projet une meilleure vision sur les risques et sur leurs interactions complexes et les aident à élaborer des réponses plus efficaces. Prenant en compte les contraintes de ressources, un algorithme glouton et un algorithme génétique sont développés pour optimiser le plan de réponse aux risques et l'allocation des réserves budgétaires. Deux exemples d'application, 1) à un projet réel de mise en scène musicale dans l'industrie du divertissement et 2) à un projet réel de construction d’un système de transport urbain, sont présentés pour illustrer l'utilité du système d'aide à la décision proposé. / Project risk management is a crucial activity in project management. Nowadays, projects are facing a growing complexity and are thus exposed to numerous and interdependent risks. However, existing classical methods have limitations for modeling the real complexity of project risks. For example, some phenomena like chain reactions and loops are not properly taken into account. This Ph.D. thesis aims at analyzing propagation behavior in the project risk network through modelling risks and risk interactions. An integrated framework of decision support system is presented with a series of proposed methods. The construction of the project risk network requires the involvement of the project manager and the team of experts using the Design Structure Matrix (DSM) method. Simulation techniques are used and several network theory-based methods are developed for analyzing and prioritizing project risks, with respect to their role and importance in the risk network in terms of various indicators. The proposed approach serves as a powerful complement to classical project risk analysis. These novel analyses provide project managers with improved insights on risks and risk interactions under complexity and help them to design more effective response actions. Considering resource constraints, a greedy algorithm and a genetic algorithm are developed to optimize the risk response plan and the allocation of budget reserves dedicated to the risk management. Two examples of application, 1) to a real musical staging project in the entertainment industry and 2) to a real urban transportation system implementation project, are presented to illustrate the utility of the proposed decision support system.
82

Proposta de modelo e implementação de um sistema de apoio à decisão em pequenas indústrias. / Sem título em inglês

Reinaldo Pacheco da Costa 25 August 1998 (has links)
O trabalho apresenta o sistema de apoio à decisão - SAD, projetado especificamente para pequenas indústrias. A pesquisa concentrou-se em parte no estudo das disciplinas envolvidas no tema análise econômico-financeira de empresas, de forma a recuperar as teorias e conceitos mais pertinentes, para, numa segunda etapa, aplicá-las ao projeto e implementação de um sistema de apoio às decisões de pequenas indústrias. O sistema de apoio à decisão - SAD foi concebido em parceria com 107 empresas de São Paulo, com o objetivo de realizar, de forma acurada e rápida, várias análises de apoio à tomada de decisões, entre as quais destacam-se as seguintes: análise das relações custo - volume - lucro (CVL); análise por taxa-alvo de retorno; cálculo de preços (orçamentos); análise econômica de seleção de produtos e de terceirizações de produtos, subconjuntos e operações. Além de específicas análises de administração financeira, outras relativas ao planejamento da produção são também colocadas à disposição pelo SAD, como é o caso do planejamento de materiais e de subconjuntos - MRP-I, do planejamento de capacidade para operações e máquinas - CRP, e do diagrama De-Para para apoiar arranjo físico, entre outras. O sistema tem oferecido apoio a uma série de tomadas de decisões em pequenas indústrias do Estado de São Paulo, com efetiva melhoria dos seus resultados econômico-financeiros. / This study presents a decision support system - simplified in portuguese as SAD, specifically designed to small manufacturing companies. The research concentrated partly on the study of the disciplines involved in economic-financial analysis of companies, in way to recover the theories and more pertinent concepts, for, in a second stage, to apply them to the project of a decision support system of industries of small load. The SAD was conceived and validated in partnership with 107 small manufacturing companies of São Paulo. It uses Managerial Accounting and Microeconomic models as long as Industrial Engineering methods. The research priorizes practical relevant managerial issues. The SAD was designed to realize accurately and rapidly several analysis to support decision making. The following analysis were highlighted: profit-cost-volume, target rate of return, pricing, products\' selection mix and make-or-buy decisions. Besides specifically financial management analysis, others relative to production planning were made available by the SAD, as materials requirements planning (MRP), capacity requirements planning (CRP), and the \"Chart of weighted values\" that supports lay out. The decision support system - SAD offered decision support to several small manufacturing companies, with effective improvement in their economical, financial and operational results.
83

Simulação da produção de madeira serrada

Heinrich, Daniele January 2010 (has links)
O aumento da competição e a aceleração dos avanços tecnológicos têm contribuído para o desenvolvimento de novos conceitos e estratégias de produção, direcionando as empresas à busca contínua de novas oportunidades de negócios e melhorias dos processos produtivos. A indústria de madeira serrada no Brasil, na sua grande maioria, apresenta estrutura produtiva precária, com baixa produtividade, e sua sobrevivência depende da busca por melhorias de eficiência técnica e econômica dos processos de transformação. Nesta busca de melhorias de processos, a simulação de sistemas pode ser utilizada como ferramenta de apoio à decisão no planejamento da produção de serrarias, contribuindo para a competitividade das empresas. Esta dissertação objetiva desenvolver um modelo de simulação da produção de madeira serrada para auxiliar no planejamento da produção de uma serraria. O trabalho verificou a real potencialidade do uso da simulação no processo produtivo da serraria, se mostrando uma alternativa para o planejamento da produção da mesma. Com o uso da ferramenta estudada, o sistema produtivo foi modelado e validado utilizando o pacote de simulação Arena. Dentre os resultados desta dissertação, podem ser destacados: o modelo de pesquisa, a identificação das variáveis do sistema, o desenvolvimento e a validação do modelo. / The growing competition and the acceleration of technological advances have been contributing for the development of new production concepts and strategies, guiding companies into the search for continuous new business opportunities and productive processes improvements. Most of sawn wood industry in Brazil presents poor productive structure with low productivity, and its survival depends on the search for improvements on technical and economic efficiency of transformation processes. On this search, system simulation can be used as a supporting tool when deciding about the saw production planning, which contributes in favor of company competition. This paper work aims the development of a sawn wood production simulation model in order to help in the planning of a sawmill production. This work verifies the real potentiality when using the simulation during the sawmill productive process, which demonstrates it can be an alternative for the planning of the sawmill production. After using the above studied tool, the productive system was modeled and validated based on Arena simulation package. Among all the results of this study, some deserve to be highlighted: the research model, the identification of the system variables, and the model development and validation.
84

Modelagem integrada de recursos hídricos com apoio de um sistema de informações geográficas / Water resources integrated modeling supported by a geographic information system

Cristiano das Neves Almeida 13 February 2006 (has links)
A carência, absoluta ou relativa, de água direcionou diversas ações no sentido de amenizar esse problema. A política nacional de recursos hídricos (Lei 9.433/97), com seus cinco instrumentos de gestão e planejamento, pode ser considerada o principal marco. Entre esses instrumentos, encontra-se o sistema de informações, que tem por finalidade coletar, armazenar e disponibilizar dados para uma gestão racional. É nesse âmbito e no sentido de contribuir para a evolução desses sistemas, que se apresenta essa tese de doutoramento. O tema principal trata da implementação de um sistema de suporte a decisões – SSD com base nos conceitos da programação orientada a objetos – POO, forma esta de programação que procura representar os sistemas por meio de classes de maneira a buscar a semelhança à realidade. Esse SSD, denominado de ARENA (análise de recursos naturais), é composto de um sistema de informações geográficas – SIG, dois simuladores (simulação do fluxo de águas subterrâneas e do ciclo hidrológico superficial), uma base de dados georeferenciada e módulos de acesso aos dados. A forma como os simuladores foram implementados, baseado em conceitos da POO e suas integrações às entidades geométricas do SIG, é apresentada como contribuição. No ARENA, o SIG não é apenas utilizado nas fases de pré e pós-processamento de dados para modelos, e sim no processo de simulação. Aplicações do ARENA a uma bacia hidrográfica (escoamento superficial) e a dois sistemas hipotéticos (escoamento subterrâneo) são apresentados ao final do trabalho. A maneira como esse SSD foi implementado induz ao desenvolvimento de simuladores adicionais sem realizar modificações nos pacotes já implementados neste trabalho, sendo facilitada a utilização dos pacotes que compõem esse SSD / The relative or complete lack of water has been directing various actions in order to solve this problem. The national water resources politic (Law 9.433/97) with its five instruments for water resources planning and management can be considered the main action. Among these instruments, it is found the information system that has as purpose to collect, store and turn it into available data to the rational management. In this scope and in order to give some contributions to the improvement of these systems, this Ph.D. thesis is presented. The main topic deals with the decision support system (DSS) implementation based on oriented object – OO, a kind of programming which tries to represent systems through classes very closely to the reality. This DSS, called ARENA (análise de recursos naturais, in Portuguese), is made up of a geographic information system (GIS), two models (a groundwater model and a distributed rainfall-runoff model), a georeferenced database and graphic user interfaces (GUI). The way the models were built, based on OO concepts and its integration to GIS geographic data, is presented as contribution. In the ARENA, the GIS is not only used in the pre and post processing steps, but also in the simulation. The ARENA applications were carried out for two examples, a watershed (surface water simulation) and a hypothetic system (groundwater simulation), both presented in the end of this study. The way this DSS was built induces to the development of other models without modifications in the existing packages, so that the development of new applications becomes easy because the use of existing packages that made this DSS up
85

Contribution à la mise en place d’une méthodologie générique de contrôle des processus de forgeage dans le but de maitriser les moyens de production / A generic methodology to improve the forging process monitoring in order to master the means of production

Allam, Zakaria 06 November 2014 (has links)
Actuellement, les moyens et les méthodes de mesure et de contrôle des procédés de mise en forme, en particulier pour le forgeage, restent limités. Ils ne sont pas systématiques et sont très souvent développés pour des cas particuliers. La robustesse de ces procédés de mise en forme dépend de la capacité à mettre en œuvre des méthodes de maîtrise du processus et des contrôles efficaces. Des méthodologies existantes, comme la DMAIC, permettent de déterminer les paramètres à contrôler et leur influence sur les variables produit, cependant cette démarche possède des inconvénients rendant difficile son application, par exemple, la dépendance de cette méthode aux experts décidant des choix des paramètres. L'idée est de mettre en place une méthodologie générique permettant aux forgerons de maîtriser leur processus de fabrication de manière efficace et efficiente. La méthodologie consiste à mettre en place deux systèmes en amont et en aval du processus de forgeage. Le premier système, en amont, est un système d'aide à la décision reliant les spécifications sur le produit (géométrie, absence de défauts…) et sur les moyens de production aux paramètres processus. Ce premier système doit permettre de déterminer les paramètres clés à surveiller pour éviter des déviations au niveau des variables produit. Le deuxième système, en aval, est un système d'apprentissage dont le but est d'aider dans la compréhension du processus, renseigner le système d'aide à la décision et déterminer la pertinence de contrôle. / The mastering of the forging process is one of the principal objectives of the forging industry. To master a forging process, the key process parameters must be identified and controlled through a specified methodology. Some controlled parameters exist, like the stroke length or the lubrication, which are identified and controlled through a systematic approach. Their control depends on the part to produce or on customer's constraints, rather than a rational approach. A methodology is proposed to master the forging process and to avoid a process deviation. There are some methodologies that already exist such as the DMAIC, but it has certain drawbacks. The aim is to develop a generic methodology to improve the forging process monitoring. The methodology uses two systems in the upstream and the downstream of the forging process. The first system is a decision support system that connects product specifications (geometry, absence of defects…) or other forging process specifications (tool wear, energy…) to the process parameters, using the empirical rules and physical laws. The first system determinates the key parameters to control in order to avoid product variable deviations. The second system is a learning system, this latter helps in process understanding, supply the decision support system with laws and determinate the control pertinence.
86

Transportation in Shanghai : A Decision Support System to Move towards Sustainability

Quchen, Xu, Yanping, Zhuang, Jing, Lu January 2010 (has links)
An excellent transportation system is integral for Shanghai as it aims for sustainable development. Decision-making has a far-reaching impact on transportation, which should be improved and supplied with assistance. This thesis aims to design a tool based on a Decision Support System (DSS) named the Transportation Sustainability Decision Support System (TSDSS). The Framework for Strategic Sustainable Development (FSSD) is a key element that was integrated in the TSDSS which will guide the users to backcast from sustainability principles to be strategic in moving transportation in Shanghai towards sustainability. The TSDSS has 3 modules based on the ABCD method and 4 base systems including a Database System, a Model Base System, a Method Base System and a Knowledge Base System, which are designed to help Shanghai’s transportation system move in the right direction towards sustainability.
87

A decision support system for conduct hydropower development

Loots, Ione January 2013 (has links)
Cheap and reliable electricity is an essential stimulus for economic and social development. Currently fossil fuels are used for the majority of global electricity generation, but energy shortages and pressure on all industries to reduce CO2 emissions provide incentives for growing emphasis on the development of alternative energy-generation methods. Presently hydropower contributes about 17% of global energy generation, which is only a fraction of its total potential. In Africa only 5% of its estimated hydropower potential has been exploited, making it the most underdeveloped continent in terms of hydropower. An often overlooked source of hydropower energy is found in conduits, where pressure-reducing stations (PRSs) are installed to dissipate excess energy. The energy dissipated by these devices can instead be captured as hydroelectricity if turbines are installed in the conduits, either by replacing pressure-reducing valves (PRVs) with a turbine, or by installing the turbine in parallel with the PRV. An initial scoping investigation indicated that significant potential exists for small-scale hydropower installations in water-distribution systems in South Africa. Almost all of the country’s municipalities and water-supply utilities have pressure-dissipating stations in their water-distribution systems, where hydropower potential may exist. This dissertation reflects the development of a Conduit Hydropower Decision Support System (CHDSS), summarised in a series of flow diagrams that illustrate the developmental process (Figure i(a) provides an example). A Conduit Hydropower Development (CHD) Tool was developed to facilitate the calculation of necessary factors (the Phase 1 Economic Analysis is shown in Figure i(b)). The objective of this CHDSS was to assist municipalities and engineers in identifying conduit hydropower potential in South Africa and to provide proper guidance for the development of potential sites. / Dissertation (MEng)--University of Pretoria, 2013. / gm2014 / Civil Engineering / Unrestricted
88

Epidemiology of early blight on potatoes in South Africa

Van der Waals, Jacquie E. (Jacqueline Elise) 11 May 2005 (has links)
Early blight (Alternaria solani Sorauer)is a major foliar disease of potatoes in most growing regions of the world and is underestimated in South Africa. This project studies the epidemiology and control of the disease in South Africa. A decision support system (DSS) for early blight in South Africa was developed and evaluated in field trials. This early blight DSS is the first such system to be developed in South Africa and once incorporated with the late blight model, will represent innovative technology for use in the South African potato industry. Trends in weather variables and concentrations of airborne conidia of A. solani were monitored. Distinct seasonal variation was noted. Peaks in spore concentration coincided with periods favourable for spore formation and dispersal; most notable was diurnal periodicity and interrupted wetting periods. The results obtained from these measurements will be useful in improving early blight DSSs for southern Africa. Isolates of A. solani from various potato-growing regions in South Africa were characterized using virulence, vegetative compatibility (VC) and random amplified microsatellite (RAMS) primers. Neither the virulence assays nor VC tests sufficiently characterised the population. Analysis of RAMS profiles revealed 27% genetic diversity among the isolates. This value is similar to diversity values obtained by previous authors studying A. solani, however, it is relatively high for an asexually reproducing fungus. There was no evidence for geographical clustering of isolates, indicating that isolates are widespread across South Africa. A survey on control practices and grower perceptions of early blight in South Africa was conducted using a questionnaire. These questionnaires were distributed to growers from 10 potato-growing regions in South Africa. Results highlighted the most popular control methods and cultivars in the South African potato industry. The majority of respondents indicated that they would use an accurate, cost-effective early blight DSS, and that more research is necessary on early blight in South Africa. A survey on control practices and grower perceptions of early blight in South Africa was conducted using a questionnaire. These questionnaires were distributed to growers from 10 potato-growing regions in South Africa. Results highlighted the most popular control methods and cultivars in the South African potato industry. The majority of respondents indicated that they would use an accurate, cost-effective early blight DSS, and that more research is necessary on early blight in South Africa. Estimated crop losses ranged from 1% - 60%, with an average of approximately 20%. This is the first comprehensive epidemiological study to be conducted on early blight in South Africa and has highlighted the need for further research. / Thesis (DPhil (Plant Pathology))--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted
89

A Trans-Dimensional View of Drug Resistance Evolution in Multiple Myeloma Patients

Jacobson, Timothy 23 March 2016 (has links)
Multiple Myeloma (MM) is a treatable, yet incurable, malignancy of bone marrowplasma cells. This cancer affects many patients and many succumb to relapse of tumor burden despite a large number of available chemotherapeutic agents developed for therapy. This is because MM tumors are heterogeneous and receive protection from therapeutic agents by the microenvironment and other mechanisms including homologous MM-MM aggregation. Therefore, therapy failure and frequent patient relapse is due to the evolution of drug resistance, not a lack of available drugs. To analyze and understand this problem, the evolution of drug resistance has been explored and presented herein. We seek to describe the methods through which MM cells become resistant to therapy, and how this resistance evolves throughout a patient’s treatment history. We achieve this in five steps. First we review the patient’s clinical history, including treatments and changes in tumor burden. Second, we trace the evolutionary tree of sub-clones within the tumor burden using standard of care fluorescence in situ hybridization (FISH). Thirdly, immunohistochemistry slides are stained and aligned to quantify the level of environmental protection received by surrounding cells and plasma in the bone marrow microenvironment (coined environment mediated drug resistance score [EMDR]). The fourth analysis type is produced through a novel 384-well plate ex vivo chemosensitivity assay to quantify sensitivity of primary MM cells to chemotherapeutic agents and extrapolate these findings to 90-day clinical response predictions. In addition to direct clinical application in the choice of best treatment, this tool was also used to study changes in sensitivity of patient tumors to other drugs, and it was observed that, upon relapse, in addition to developing resistance to the current line of therapy, tumors become cross-resistant to agents that they were never exposed to. Finally, MM-MM homologous aggregation is quantified to assess the level of drug resistance contributed by clustering of patient tumor cells, which causes upregulation of Bcl-2 expression and other resistance mechanisms1. The findings of such experimentation improve comprehension of the driving factors that contribute to drug resistance evolution on a personalized treatment basis. The aforementioned factors all contribute in varying degrees for unique patient cases, seven of which are presented in depth for this project. In summary: Environmental protection plays a critical initial role in drug resistance, which is followed by increase in tumor genetic heterogeneity as a result of mutations and drug-induced Darwinian selection. Eventually, environment-independent drug resistant subpopulations emerge, allowing the tumor to spread to unexplored areas of the bone marrow while maintaining inherited drug resistant phenotype2. It is our hope that these findings will help in shifting perspective regarding optimal management of MM by finding new therapeutic procedures that address all aspects of drug resistance to minimize chance of relapse and improve quality of life for patients.
90

Business intelligence: Požadavky na výběr softwaru a jeho přínosy / Business intelligence: Requirements and benefits

Jíra, Martin January 2013 (has links)
The thesis focuses on requirements, which must be established when business intelligence is chosen, from user point of view. Business intelligence je decision support system and it is very important, that system must be ease of use and provide expected information for analyst and managers. During the process of choosing the software, they are the one, who provide requirements and expectation of the system. The thesis focuses on mapping those requirements and their importance using survey among analyst and managers, who uses business intelligence or want to use it.

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