• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 132
  • 110
  • 34
  • 25
  • 15
  • 14
  • 4
  • 3
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 398
  • 41
  • 36
  • 33
  • 29
  • 28
  • 28
  • 26
  • 26
  • 25
  • 24
  • 23
  • 22
  • 22
  • 21
  • 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

Caminhoneiros, caminhos e caminhões: uma etnografia sobre mobilidades nas estradas / Truckers, routes and trucks: an ethnography of mobilities on the roads

Gomes, Arthur Fontgaland 30 November 2017 (has links)
Esta dissertação busca identificar os elementos integrados pelos caminhoneiros autônomos em suas vidas móveis. Analisa como estes motoristas extraem permanência de suas mobilidades, constitutivas desses modos de vidas. Os caminhoneiros são profissionais especializados em operar veículos automotores de carga e fazer circular mercadorias a partir do transporte rodoviário. Trata-se de um conjunto disperso e heterogêneo que executa grandes jornadas de trabalho distantes de seus endereços fixos, para onde retornam intermitentemente. Sem desvincular-se dos cotidianos mais sedentários, intensificam o convívio com os caminhões e as estradas. Instrumento de trabalho, mas também casa móvel, o caminhão é onde se realiza obrigações, prazeres e lazeres. Os veículos adquirem diverso usos, modificações, valores, afetos e podem operar nas distinções entre pares. Cuidados de si e dos caminhões se misturam e revestem a boleia de domesticidade masculina que ajuda a viabilizar o ser caminhoneiro. Nas estradas, cumpre-se o itinerário, cujas rotas e prazos são estipulados pelo mercado. O itinerário é preenchido pelos caminhoneiros por intensas negociações entre tarefas laborais e extralaborais manifestadas nas escolhas e efetivações das paradas que pontuam o trajeto. Nos estabelecimentos comerciais, os motoristas se vinculam ao pessoal do posto, chapas e putas. São interações afetivas, trabalhistas, sexuais e de consumo que se articulam e animam as estradas. Tendo em vista a vida social das BRs esta etnografia se desenvolveu a partir de caronas nas boleias de caminhão, um tipo de mobilidade informal e gratuita inteligível neste contexto, em especial, para os caminhoneiros. As teorias elaboradas pelos motoristas inspiraram esta dissertação e suscitam dialogo com algumas discussões acadêmicas sobre mobilidades e trabalho caminhoneiro no campo das humanidades. Com isso, leva-se em conta que quando os motoristas e caminhões se movem pelas estradas, não só as mercadorias são postas em circulação através de itinerários. Junto a elas se movimentam também certa economia corporal, material e simbólica numa trama adensada de relações que cria e recria caminhos. Estes, indispensáveis para a permanência dessas vidas móveis. / This dissertation aims to identify what are the elements that truck drivers integrate in their mobile lives. We analyze how these truck drivers extract permanence of their mobilities, constitutive of those ways of living. The truck drivers professionals specializes in operate cargo automotive vehicles, transporting goods across the road network. They are a heterogeneous disperse set of professionals performing long work periods away from their fixed homes, to which they return intermittently. Thus, they keep bonds with their settled dwellings while they intensify their sociality with trucks and roads. The truck is both a work tool and a mobile house, where they perform duties, pleasures and leisure. The vehicles are put to different uses, customizations, values, affections and may engender distinction amongst colleagues. Drivers intertwine self-care and truck maintenance, investing the truck lorry of a masculine domesticity which instantiate what is to be a truck driver. On the road, an itinerary is fulfilled, with market stipulated routes and schedules. Meanwhile, truck drivers entangle their itinerary with intense negotiations between work tasks and other activities, which take place in the truck drivers choices of where they stop along the way. At side road shops and stores, drivers relate to gas station workers, local guides and prostitutes. Labor, affective, sexual and consumption relations that makes the road alive. Regarding the social life of Brazilian federal highways and roads, this ethnographic research was carried out by means of hitchhiking truck lorries, a free and non-official way of faring used to translate to the drivers the anthropological research. The theories conceived by those truckers have inspired this work and are presented in dialogue with academic debates on mobilities and truck drivers professional realities. Thus, we consider that not only goods are set in motion when drivers and trucks fare their itineraries, but there is also a specific bodily, material and symbolic economy moving along a thick meshwork of relations that make and unmake paths. Those are constitutive of the permanence of those mobile lives.
112

Directed polymers and rough paths

Tapia Muñoz, Nikolas Esteban January 2018 (has links)
Tesis para optar al grado de Doctor en Ciencias de la Ingeniería, Mención Modelación Matemática / Las Ecuaciones Estocásticas en Derivadas Parciales (SPDEs por su sigla en inglés) son una herramienta esencial para el análisis de los límites de escalamiento de diversos modelos microscópicos provenientes de otras áreas de las ciencias tales como la física y la química. Este tipo de ecuaciones corresponde a una ecuación en derivadas parciales clásica a la cual se le ha agregado un término de forzamiento externo aleatorio el que suele ser muy irregular; el ejemplo más sencillo es tal vez la Ecuación del Calor Estocástica, de la cual una de sus versiones es estudiada en la presente tesis. En cualquier caso, la irregularidad de este potencial hace que el análisis de las soluciones de estos problemas sea mucho más complicado. En efecto, hay casos en que dichas soluciones sólo pueden ser entendidas en el sentido de las distribuciones. Hay casos más críticos como la ecuación de Kardar--Parisi--Zhang (KPZ) en en una dimensión espacial donde, si bien se puede probar que posee soluciones Hölder, estas no son lo suficientemente regulares para permitir definir uno de los términos no lineales que aparecen en ella. Durante los últimos 20 años se han desarrollado varias técnicas para el análsis de este tipo de ecuaciones, entre las que destacan la teoría de rough paths geométricos de T. Lyons (1998), los rough paths ramificadosde M. Gubinelli (2010), y la más reciente teoría de estructuras de regularidad de M. Hairer (2014) por la que este último obtuvo la medalla Fields en 2014. Aunque diferentes, todas estas técnicas tienen como idea central el concepto de renormalización. En particular, la renormalización de Wick juega un rol esencial en la renormalización en el marco de las estructuras de regularidad. En este trabajo se desarrollan los productos y polinomios de Wick desde un punto de vista algebraico inspirado en el cálculo umbral de G.-C. Rota. También se explora la teoría general de losrough paths en general y su versión ramificada en particular, probándose nuevos resultados en la dirección de incorporar un análogo de la renormalización de Wick existente en las estructuras de regularidad. Por último, se estudia el modelo de polímero semidiscreto multicapas introducido por I. Corwin and A. Hammond (2014) para el cual se prueba la convergencia de su función de partición hacia la "solución" de la Ecuación del Calor Estocástica multicapas definida por N. O'Connell y J. Warren (2011) algunos años antes. Cabe destacar que al momento de redacción de esta tesis no existen resultados que permitan interpretar este proceso en el continuo como la solución de una SPDE singular como en el caso de la ecuación de KPZ, lo que ha sido una de las principales fuentes de inspiración para este trabajo. / CONICYT/Doctorado Nacional/2013-21130733 CMM - Conicyt PIA AFB170001
113

Aboriginal Dreaming Tracks or Trading Paths: The Common Ways

Kerwin, Dale Wayne, n/a January 2006 (has links)
This thesis recognises the great significance of 'walkabout' as a major trading tradition whereby the Dreaming paths and songlines formed major ceremonial routes along which goods and knowledge flowed. These became the trade routes that criss-crossed Australia and transported religion and cultural values. The thesis also highlights the valuable contribution Aboriginal people made in assisting the European explorers, surveyors, and stockmen to open the country for colonisation, and it explores the interface between Aboriginal possession of the Australian continent and European colonisation and appropriation. Instead of positing a radical disjunction between cultural competencies 'before' and 'after', the thesis considers how European colonisation of Australia (as with other colonial settings) appropriated Aboriginal competence in terms of the landscape: by tapping into culinary and medicinal knowledge, water and resource knowledge, hunting, food collecting and path-finding. As a consequence of this assistance, Aboriginal Dreaming tracks and trading paths also became the routes and roads of colonisers. This dissertation seeks to reinstate Aboriginal people into the historical landscape of Australia. From its beginnings as a footnote in Australian history, Aboriginal society, culture, and history has moved into the preamble, but it is now time to inscribe Aboriginal people firmly in the body of Australian history.
114

Congestion Removal in the Next Generation Internet

Suryasaputra, Robert, rsuryasaputra@gmail.com January 2007 (has links)
The ongoing development of new and demanding Internet applications requires the Internet to deliver better service levels that are significantly better than the best effort service that the Internet currently provides and was built for. These improved service levels include guaranteed delays, jitter and bandwidth. Through extensive research into Quality of Service and Differentiated Service (DiffServ) it has become possible to provide guaranteed services, however this turns out to be inadequate without the application of Traffic Engineering methodologies and principles. Traffic Engineering is an integral part of network operation. Its major goal is to deliver the best performance from an existing service provider's network resources and, at the same time, to enhance a customers' view of network performance. In this thesis, several different traffic engineering methods for optimising the operation of native IP and IP networks employing MPLS are proposed. A feature of these new methods is their fast run times and this opens the way to making them suitable for application in an online traffic engineering environment. For native IP networks running shortest path based routing protocols, we show that an LP-based optimisation based on the well known multi-commodity flow problem can be effective in removing network congestion. Having realised that Internet service providers are now moving towards migrating their networks to the use of MPLS, we have also formulated optimisation methods to traffic engineer MPLS networks by selecting suitable routing paths and utilising the feature of explicit routing contained in MPLS. Although MPLS is capable of delivering traffic engineering across different classes of traffic, network operators still prefer to rely on the proven and simple IP based routing protocols for best effort traffic and only use MPLS to route traffic requiring special forwarding treatment. Based on this fact, we propose a method that optimises the routing patterns applicable to different classes of traffic based on their bandwidth requirements. A traffic engineering comparison study that evaluates the performance of a neural network-based method for MPLS networks and LP-based weight setting approach for shortest path based networks has been performed using a well-known open source network simulator, called ns2. The comparative evaluation is based upon the packet loss probability. The final chapter of the thesis describes the software development of a network management application called OptiFlow which integrates techniques described in earlier chapters including the LP-based weight setting optimisation methodology; it also uses traffic matrix estimation techniques that are required as input to the weight setting models that have been devised. The motivation for developing OptiFlow was to provide a prototype set of tools that meet the congestion management needs of networking industries (ISPs and telecommunications companies - telcos).
115

Cycle systems : an investigation of colouring and invariants /

Burgess, Andrea, January 2005 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2005. / Bibliography: leaves 78-83.
116

Modelling and analysis of engineering changes in complex systems

Lemmens, Yves Claude Jean January 2007 (has links)
Complex products are comprised of a large number of tightly integrated components, assemblies and systems resulting in extensive logical and physical interdependences between the constituent parts. Thus a change to one item of a system is highly likely to lead to a change to another item, which in turn can propagate further. The aim of this research therefore is to investigate dependency models that can be used to identify the impact and trace thepropagation of changes in different information domains, such as requirements, physical product architecture or organisation. Cont/d.
117

Prospects and Challenges of Multi-Layer Optical Networks

HASEGAWA, Hiroshi, SATO, Ken-ichi 01 August 2007 (has links)
No description available.
118

Improving Tool Paths for Impellers

Kuo, Hsin-Hung 02 September 2004 (has links)
Impellers are important components in the field of aerospace, energy technology, and precision machine industries. Considering the high accuracy and structural integrity, impellers might be manufactured by cutting. Due to their complex geometries and high degrees of interference in machining, multi-axis machines are requested to produce impellers. The object of this thesis is to improve 5-axis tool paths for surface quality of impellers by smoothing point cutting tool paths in terms of linear segments and B-Splines and by using flank milling technologies with linear segment and B-Splines tool paths. Experimental results show that the surface quality of impeller blades can be improved by point cutting with smoothed tool paths and by flank milling. Moreover, the required milling time can be reduced by 18 percent and 13percent based on smoothed linear tool paths and smoothed B-Splines tool paths, respectively.
119

Identification Of Risk Paths In International Construction Projects

Eybpoosh, Matineh 01 September 2010 (has links) (PDF)
Within the context of construction projects, risk is generally defined as an uncertain happening which is the function of its occurrence probability and the severity of its possible impacts on pre-defined objectives. According to this definition, international construction projects are high-risk endeavors, since they are known with their complex natures, large sizes, multidisciplinary frameworks, and unfamiliar and uncertain environments. International construction projects have more complex risk emergence patterns as they are affected from multiple global and foreign country conditions as well as project-related factors. Huge and complicated interrelationships and dynamic interactions among these influencing factors necessitate more systematic, comprehensive, and multi-attribute risk management process for overseas projects. In order to satisfy the requirements of such a risk management system, a realistic, inclusive, and accurate picture of the real case, reflecting all the aforementioned aspects of the international projects, is necessary. The major aim of this study is to demonstrate that there are causal relationships between various risk factors which necessitate identification of risk paths rather than individual risk factors during risk identification and assessment phases. Identification of a network of interactive risk paths, each of which initiated from diverse v vulnerabilities of the project system, is considered to be a better reflection of the real conditions of construction projects rather than using generic risk checklists. In this study, using the data of 166 projects carried out by Turkish contractors in international markets, and utilizing Structural Equation Modeling (SEM) technique, 36 interrelated risk paths were identified and the total effects of each vulnerability factor and risk path on cost overrun were assessed. SEM findings prove the main hypotheses of the study. The results demonstrate that every risk path is generated from specific vulnerabilities of inherent in project environment. Risk identification using SEM helps decision-makers in answering &ldquo / what-if&rdquo / questions in early stages of a project, in tracing the effects of interdependent risks throughout the life of the project, and in evaluating the influence of alternative mitigation strategies, not only on specific risks, but also on the whole network of interrelated risk factors.
120

Green mode : pedestrian and cycling : a design strategy for Tin Shui Wai /

Mehmood, Bilal. January 1995 (has links)
Thesis (M.U.D.)--University of Hong Kong, 1996. / Includes bibliographical references (leaves 75-79).

Page generated in 0.1165 seconds