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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.
431

Avaliação da estabilidade, capacidade e implantação de práticas lean em obras de infraestrutura e pavimentação viária

Freitas, Saulo Joaquim de January 2015 (has links)
O setor da construção civil é conhecido pela grande incidência de perdas em seus processos, o que tem levado ao crescente uso de práticas baseadas nos sistemas de produção enxuta. Este trabalho apresenta a avaliação da estabilidade e capacidade dos processos, bem como o uso de práticas enxutas em uma obra de pavimentação viária. Inicialmente, a avaliação da estabilidade e capacidade foi realizada por meio do mapeamento do fluxo de valor do estado atual e do desenvolvimento e coleta de indicadores associados aos 4M (Material, Mão-deobra, Máquina e Método). Os resultados indicaram que todos os cinco indicadores avaliados foram estáveis, porém apenas um indicador demonstrou capacidade de atender os parâmetros do cliente. Com base nessa avaliação, foram adotadas ações para redução de perdas e melhora da estabilidade e capacidade dos processos, por meio do uso de práticas enxutas, aplicadas em uma segunda obra com características similares à anterior. As práticas usadas foram: i) Mudança e melhoria de alguns processos construtivos; ii) implantação de ferramenta 5S no canteiro de obras; iii) criação e implantação de dispositivos poka-yokes, iv) aplicação de dispositivo visual de comunicação do tipo andon; v) planejamento de entrega de materiais just-in-time. Nessa segunda obra, os indicadores se mantiveram estáveis, mas foi percebida uma melhora quanto à capacidade destes indicadores em atender os parâmetros exigidos. Apenas o indicador de mão-de-obra turn over não foi capaz de atender a meta definida pela empresa. / The Building Sector is known for high incidence of wastes in its process. This characteristic has been motivating the operators to use some practices based on Lean Production Systems. This paper presents an evaluation of the stability and capacity of Lean Construction concepts in a road construction work. The evaluation of the stability and capacity was realized mapping the current state value stream and the collection of indicators associated with the 4M (Material Hand labor, Machine and Method) The results indicated that all seven indicators measured were stable, but only an indicator of the seven evaluated was considered capable. Based on this evaluation, actions were taken to improve the stability and capacity through the use of lean practices, applied in a second work with similar characteristics to the previous. The practices used were: i) improving / changing some construction processes, ii) 5S tool deployment on construction of works iii) creation and implementation of poka-yokes devices, iv) application of visual tool of andon type communication, v) delivery planning materials within the just-in-time concept. In this second work the indicators remained stable, but a great improvement was perceived, related to the ability of the indicators to meet the required parameters. Only the hand labor turnover indicator was not able to meet the target set by the company.
432

Avaliação da estabilidade, capacidade e implantação de práticas lean em obras de infraestrutura e pavimentação viária

Freitas, Saulo Joaquim de January 2015 (has links)
O setor da construção civil é conhecido pela grande incidência de perdas em seus processos, o que tem levado ao crescente uso de práticas baseadas nos sistemas de produção enxuta. Este trabalho apresenta a avaliação da estabilidade e capacidade dos processos, bem como o uso de práticas enxutas em uma obra de pavimentação viária. Inicialmente, a avaliação da estabilidade e capacidade foi realizada por meio do mapeamento do fluxo de valor do estado atual e do desenvolvimento e coleta de indicadores associados aos 4M (Material, Mão-deobra, Máquina e Método). Os resultados indicaram que todos os cinco indicadores avaliados foram estáveis, porém apenas um indicador demonstrou capacidade de atender os parâmetros do cliente. Com base nessa avaliação, foram adotadas ações para redução de perdas e melhora da estabilidade e capacidade dos processos, por meio do uso de práticas enxutas, aplicadas em uma segunda obra com características similares à anterior. As práticas usadas foram: i) Mudança e melhoria de alguns processos construtivos; ii) implantação de ferramenta 5S no canteiro de obras; iii) criação e implantação de dispositivos poka-yokes, iv) aplicação de dispositivo visual de comunicação do tipo andon; v) planejamento de entrega de materiais just-in-time. Nessa segunda obra, os indicadores se mantiveram estáveis, mas foi percebida uma melhora quanto à capacidade destes indicadores em atender os parâmetros exigidos. Apenas o indicador de mão-de-obra turn over não foi capaz de atender a meta definida pela empresa. / The Building Sector is known for high incidence of wastes in its process. This characteristic has been motivating the operators to use some practices based on Lean Production Systems. This paper presents an evaluation of the stability and capacity of Lean Construction concepts in a road construction work. The evaluation of the stability and capacity was realized mapping the current state value stream and the collection of indicators associated with the 4M (Material Hand labor, Machine and Method) The results indicated that all seven indicators measured were stable, but only an indicator of the seven evaluated was considered capable. Based on this evaluation, actions were taken to improve the stability and capacity through the use of lean practices, applied in a second work with similar characteristics to the previous. The practices used were: i) improving / changing some construction processes, ii) 5S tool deployment on construction of works iii) creation and implementation of poka-yokes devices, iv) application of visual tool of andon type communication, v) delivery planning materials within the just-in-time concept. In this second work the indicators remained stable, but a great improvement was perceived, related to the ability of the indicators to meet the required parameters. Only the hand labor turnover indicator was not able to meet the target set by the company.
433

Avaliação da estabilidade, capacidade e implantação de práticas lean em obras de infraestrutura e pavimentação viária

Freitas, Saulo Joaquim de January 2015 (has links)
O setor da construção civil é conhecido pela grande incidência de perdas em seus processos, o que tem levado ao crescente uso de práticas baseadas nos sistemas de produção enxuta. Este trabalho apresenta a avaliação da estabilidade e capacidade dos processos, bem como o uso de práticas enxutas em uma obra de pavimentação viária. Inicialmente, a avaliação da estabilidade e capacidade foi realizada por meio do mapeamento do fluxo de valor do estado atual e do desenvolvimento e coleta de indicadores associados aos 4M (Material, Mão-deobra, Máquina e Método). Os resultados indicaram que todos os cinco indicadores avaliados foram estáveis, porém apenas um indicador demonstrou capacidade de atender os parâmetros do cliente. Com base nessa avaliação, foram adotadas ações para redução de perdas e melhora da estabilidade e capacidade dos processos, por meio do uso de práticas enxutas, aplicadas em uma segunda obra com características similares à anterior. As práticas usadas foram: i) Mudança e melhoria de alguns processos construtivos; ii) implantação de ferramenta 5S no canteiro de obras; iii) criação e implantação de dispositivos poka-yokes, iv) aplicação de dispositivo visual de comunicação do tipo andon; v) planejamento de entrega de materiais just-in-time. Nessa segunda obra, os indicadores se mantiveram estáveis, mas foi percebida uma melhora quanto à capacidade destes indicadores em atender os parâmetros exigidos. Apenas o indicador de mão-de-obra turn over não foi capaz de atender a meta definida pela empresa. / The Building Sector is known for high incidence of wastes in its process. This characteristic has been motivating the operators to use some practices based on Lean Production Systems. This paper presents an evaluation of the stability and capacity of Lean Construction concepts in a road construction work. The evaluation of the stability and capacity was realized mapping the current state value stream and the collection of indicators associated with the 4M (Material Hand labor, Machine and Method) The results indicated that all seven indicators measured were stable, but only an indicator of the seven evaluated was considered capable. Based on this evaluation, actions were taken to improve the stability and capacity through the use of lean practices, applied in a second work with similar characteristics to the previous. The practices used were: i) improving / changing some construction processes, ii) 5S tool deployment on construction of works iii) creation and implementation of poka-yokes devices, iv) application of visual tool of andon type communication, v) delivery planning materials within the just-in-time concept. In this second work the indicators remained stable, but a great improvement was perceived, related to the ability of the indicators to meet the required parameters. Only the hand labor turnover indicator was not able to meet the target set by the company.
434

Optimisation of offshore wind farm maintenance

Sinha, Yashwant January 2016 (has links)
The installed capacity of European Offshore Wind Turbines (OWT) is likely to rise from the 2014 value of 7GW to 150GW in 2030. However maintenance of OWT is facing unprecedented challenges and cost 35% of lifetime costs. This will be equivalent to £14billion/year by 2030 if current OWT maintenance schemes are not changed. However the complexities around OWT operation require tools and systems to optimise OWT maintenance. The design of optimal OWT maintenance requires failure analysis of over 10,000 components in OWT for which there is little published work relating to performance and failure. In this work, inspection reports of over 400 wind turbine gearboxes (source: Stork Technical Services) and SCADA data (source: Shetland Aerogenerators Ltd) were studied to identify issues with performance and failures in wind turbines. A modified framework of Failure Mode Effects and Criticality Analysis (i.e. FMECA+) was designed to analyse failures according to the unique requirements of OWT maintenance planners. The FMECA+ framework enables analysis and prediction of failures for varied root causes, and determines their consequences over short and long periods of time. A software tool has been developed around FMECA+ framework that enables prediction of component level failures for varied root causes. The tool currently stores over 800 such instances. The need to develop a FMECA+ based Enterprise Resource Planning tool has been identified and preliminary results obtained from its development have been shown. Such a software package will routinely manage OWT data, predict failures in components, manage resources and plan an optimal maintenance. This will solve some big problems that OWT maintenance planners currently face. This will also support the use of SCADA and condition monitoring data in planning OWT maintenance, something which has been difficult to manage for a long time.
435

La transformation du sytème bancaire dans l'Union européenne : une approche en terme de réseaux / Transformation of the banking system in the european Union : a network approach

Mirchev, Lyubomir 05 November 2013 (has links)
Ces dernières années, l’intégration des marchés financiers s’est accrue dans le monde entier. Ces marchés dépassent désormais les frontières nationales. A l’ordre du jour, la création d’instruments financiers adéquats et une démarche nouvelle, destinée à améliorer la sécurité et la stabilité du secteur financier de l’UE. L’objet de cette thèse est d’appréhender les principaux problèmes posés par la constitution et le développement du marché bancaire européen, et d’identifier les défis engendrés par les nouvelles réalités qui lui sont associées. Ce travail examine la transformation du marché bancaire européen, impacté par la crise, en mettant l’accent sur sa fonction de coordination dans l’économie. L’objectif de la thèse est d’analyser la transformation du système bancaire, d’une structure à effets différés, - c’est à dire telle que les mesures de régulation et les interventions en réponse à un problème sont différées dans le temps -, en un système opérationnel d’autorégulation fonctionnant en temps réel. Cette transformation améliorerait radicalement la stabilité et l’efficacité du système dans son ensemble. Cet objectif général conduit aux étapes suivantes : analyser le marché bancaire à travers une analyse du réseau pour mettre en évidence certaines spécificités des liens institutionnels, et contribuer ainsi à l’analyse de la transformation du secteur bancaire ; identifier les architectures de régulation et de contrôle du système bancaire pour mieux identifier sa structure actuelle de gestion et de contrôle ; appréhender le système bancaire comme une infrastructure critique relevant d’une approche en termes de réseau, et analyser ses propriétés de stabilité et d’efficacité dans le domaine financier (bancaire), d’un point de vue national et international. L’apport principal de la thèse est de fournir un modèle de surveillance en termes de réseaux, ce qui constitue un nouveau type d’architecture de contrôle du réseau financier. Ce modèle fournit une alternative aux modèles de contrôle actuels, dans l’objectif d’appréhender la structure contemporaine des marchés financiers. / In recent years, financial markets worldwide became highly integrated, overcoming national borders. The problem of developing adequate tools and comprehensive approaches for achieving higher security and stability in the EU financial sector is on the agenda. Key issues and challenges for the formation and development of the single European financial market, driven by the new realities, are considered in this thesis. The goal of this thesis is to propose and develop analyses able to contribute to the transformation of the banking system from a structure with delayed-in-time management, in which the impact of the regulatory measures and interventions in response to a particular problem is delayed in the time, into an operational self-regulating system (system of systems) operating in near real-time. This transformation would allow sharp increase in stability and operability of the system. The so defined goal implies the following more specific objectives: to analyze the banking market through the network perspective in order to reveal some aspects of the system, not typical to the particular institutions, regarded as separate entities; to analyze the regulatory and supervisory architectures for discovering the current control structure of the banking system; to explore and develop the architecture of the banking system as a separate critical infrastructure, which could enable the application of network-centric approach as an opportunity for achieving stability and efficiency (operability) in the financial sector, directly related to national and international security. The main proposition of the thesis is the creation of a new type of network supervisory architecture as an alternative to the current supervisory models in order to respond to the modern structure of the financial markets.
436

Infrastructure policy reforms and rural poverty reduction in Ghana : the case of the Keta Sea Defence Project

Garr, Ewald Quaye January 2010 (has links)
Masters in Public Administration - MPA / This mini-thesis seeks to understand why infrastructure projects fail to contribute effectively to poverty (rural) reduction. The thesis assumes that though infrastructure provision can impact positively on rural poverty reduction, the same infrastructure provision has worsened or put people in worse conditions of poverty. Therefore it is not automatic that infrastructure provision would reduce rural poverty as often held. The thesis goes on to postulate that a positive relationship between infrastructure and rural poverty reduction is best achieved within a broad or generic policy which provides the framework for providing such infrastructure. The thesis assesses these assertions empirically by first, testing the relationships between infrastructure and rural poverty reduction. Here a large scale infrastructure project in Ghana known as the Keta sea defence project serves as the case study. Secondly the thesis assesses Ghana's infrastructure provision policy environment and its implications on rural poverty reduction in the affected communities of the Keta sea defence project. / South Africa
437

Les activités maritimes de la Province d'Afrique romaine (de 46 av. J.-C. – jusqu'en 439 apr. J.-C.) / The maritime activities of the province of Roman Africa (46 av J. -C - up to 439 after J. C.)

Saidi, Ali 29 January 2016 (has links)
Il s'agit de faire la reconstitution de l'ensemble du paysage portuaire. On va aussi étudier des différents mécanismes des activités maritimes faisant des cités portuaires de la province d'Afrique romaine, des véritables centres économiques. Autrement dit, on essayera d’étudier les infrastructures portuaires et les aspects, du rôle assumé par ces villes, en tant que points de contact, entre le monde de l’arrière-pays et de l’outre-mer. Dans ce contexte, on tâchera de réexaminer plusieurs thèses, concernant l’évaluation du rôle des ports, dans le processus du commerce maritime extérieur. Cette réflexion nous amènera à examiner les aspects de l’aménagement du réseau routier terrestre ainsi que l’organisation des itinéraires maritimes, qui contribuèrent à l’écoulement de divers produits africains. On examinera également, la nature des marchandises qui constituaient les cargaisons, les divers navires partant des ports. L’organisation administrative et législative du transport, surtout de l'annone, aussi le commerce maritime, son importance, tant qu’elle nous renseigne sur les procédures employées par le pouvoir central romain, pour organiser ce commerce, enfin sur l’importance des villes portuaires, de la province d'Afrique pour Rome. / This is to reconstitute the entire port landscape. We will also study the different mechanisms of maritime activities which make the port cities of the province of Roman Africa, the real economic centers. In other words, we will try to study the port infrastructure and the aspects of the role played by these cities as points of contact between the world of inland and oversea. In this context, we will try to review several theses on the assessment of the ports role in the process of foreign maritime trade. This reflection leads us to examine aspects of the organization of land road network and the organization of maritime routes, which contributed to the flow of various African products. We also consider the nature of the goods which were the cargo, various ships from the ports. The administrative and legislative organization of transport, especially the annona, as maritime trade, its importance, as it provides information on the procedures used by the Roman central authority to organize this trade, finally the importance of port cities of the province of Africa to Rome.
438

Assessing the Management of Public Private Partnerships In Infrastructure Procurement: A Complex Evolutionary Systems Theory Perspective

Parsons, Blair January 2016 (has links)
This dissertation focuses on the findings of a multi-case study centered around two public-private partnership (P3s) projects in Ontario: the Royal Ottawa Hospital and the Brampton Civic Hospital. Partnerships have become particularly important as a part of infrastructure procurement for all levels of government in Canada. While infrastructure public-private partnerships have grown in popularity, they remain a controversial means of procuring public assets. Considerable questions remain as to whether the mechanisms related to partnerships with the private sector represent a sufficient response to the challenges facing health care systems. As such, major avenues exist for contributions in the form of evidence-based examinations to the field of knowledge pertaining to hospital procurement. A body of research literature and review of public-private partnerships, including those with a particular focus on health-sector projects in Canada, has grown over the past two decades. This study contributes an analysis of the relationship between public and private partners to that literature, utilizing a conceptual lens developed out of complex evolutionary systems theory. The study is intended to examine the capacity of public managers entering into a public-private partnership arrangement to successfully activate agents and utilize the skill and knowledge of these agents, conduct joint fact finding and consensus building, and better understand how they have arranged and organized joint interactions between the public and private sector. The two case studies demonstrate the key inputs into the decision-making processes for what were formative health infrastructure partnership projects in Ontario, providing an assessment of the degree to which the government of Ontario was successful in managing a cooperative decision-making process that stressed inclusion and horizontal steering. Results find that public managers struggled in some ways to leverage an effective horizontal management style and engage in smart interventions to utilize expert knowledge to address knowledge gaps, contributing to stagnating negotiations and driving up transaction costs for the projects. Some noteworthy successes were experienced in the case of the Royal Ottawa Hospital in leveraging private-sector knowledge to develop performance metrics, and the approach to stakeholder engagement in this case presents positive lessons-learned for future P3 infrastructure projects.
439

Charakteristika IT infrastruktury / Characteristics of IT infrastructure

Křena, Martin January 2013 (has links)
The theme of this thesis is the IT infrastructure in enterprises in the Czech Republic. Nowadays IT infrastructure exists in all companies which are trying to succeed in the competition. Outputs (services) of IT infrastructure should be monitored and managed so the company could most effectively support their core processes. For monitoring and man-agement processes can be used a variety of tools designed for management of information systems. This work deals with the evaluation of the level of IT infrastructures service man-agement. The aim of this thesis is to assess the level of IT infrastructure services manage-ment in the selected company. This work establishes methods showing appreciation of IT infrastructure service level that is applicable in all companies, regardless of their orientation. In conclusion, the methodology is tested on a real company from the IT environment.
440

Evaluation et développement de la méthode IRIP de cartographie du ruissellement. Application au contexte ferroviaire / Evaluation and development of the IRIP method of surface runoff mapping. Application to the railway context.

Lagadec, Lilly-Rose 05 December 2017 (has links)
Le ruissellement pluvial est à l’origine de phénomènes violents tels que des inondations, de l’érosion ou des coulées de boue. Les voies ferrées interceptent les écoulements de surface, ce qui peut engendrer une dégradation précoce de l’infrastructure ou la destruction d’éléments, tels que la plateforme ou les talus. La méthode IRIP, « Indicateur de Ruissellement Intense Pluviale », permet de représenter le ruissellement en trois cartes, la production, le transfert et l’accumulation. La méthode IRIP se veut simple et robuste, pour un usage sur tous types de territoires et sans calage. Comme tout modèle de ruissellement, l’évaluation de la méthode IRIP se heurte au manque de données. Pourtant, l’évaluation est une étape cruciale dans le développement de modèles. Pour un usage opérationnel ou pour poursuivre les développements, il est nécessaire d’estimer la valeur et la fiabilité des informations produites. L’objectif de la thèse est donc de proposer une méthode d’évaluation de la méthode IRIP par comparaison à des données d’impacts sur les voies ferrées. La difficulté réside dans la différence de fond et de forme des données à comparer et dans la nécessité de prendre en compte la vulnérabilité de l’infrastructure. La méthode d’évaluation proposée est basée sur le calcul de tableaux de contingence et d’indicateurs de performance, couplé à des analyses détaillées d’incidents. Après une estimation de la performance de la méthode IRIP, des développements sont testés et évalués grâce à la méthode d’évaluation élaborée. La lisibilité des cartes est finalement améliorée, tout en gardant de bons scores de performance. En appliquant la méthode IRIP à des contextes opérationnels, il est montré en quoi IRIP peut être considéré comme un outil d’aide à l’expertise. Différentes tâches du processus de gestion des risques sont testées, telles que les diagnostics de risques sur les voies ferrées, les retours d’expérience post-évènement ou encore la réalisation de zonage règlementaire. De manière générale, cette thèse contribue à l’amélioration des connaissances sur le phénomène du ruissellement et propose des méthodes pour améliorer la gestion des risques liés au ruissellement. / Surface runoff is the source of severe hazards such as floods, erosion or mudflows. Railways can disturb natural surface water flow path, which can generate accelerated deterioration of the infrastructure, or the destruction of railway elements, such as the roadbed or the embankments. The IRIP method ‘Indicator of Intense Pluvial Runoff’ (French acronym) allows mapping surface runoff through three maps, generation, transfer and accumulation. The IRIP method aims to be simple and reliable, in order to be used on all types of lands, without calibration stage. As for others surface runoff models, the IRIP method evaluation faces the lack of data. However, evaluation is a crucial stage for the development of models. In the perspective of an operational use, or simply for the model development, it is essential to estimate the value and the reliability of the model outputs. The thesis objective is to provide an evaluation method using surface runoff impacts on railways. Difficulties lie in the fact that data to be compared differ in terms of form and content. Moreover, the infrastructure vulnerability must be characterized. The proposed evaluation method is based on the computation of contingency tables and of verification indicators, together with detailed analysis of specific impacts. After an estimation of the IRIP method performance, further developments can be tested and evaluated thanks to the proposed evaluation method. Finally, maps comprehensibility is enhanced, while preserving satisfying performance scores. By applying the IRIP method to operational contexts, it has been shown how the IRIP method can be used as a tool in expert appraisals. Different tasks of the risk management process have been studied such as risk analysis on railways, post-event investigation or the realisation of regulatory zonings. More generally, this thesis contributes to improve knowledge about surface runoff and provide methods for improving the risk management.

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