• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 90
  • 41
  • 6
  • 5
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 197
  • 197
  • 197
  • 69
  • 35
  • 26
  • 25
  • 24
  • 24
  • 24
  • 22
  • 20
  • 18
  • 15
  • 15
  • 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.
141

Gis-based Stochastic Modeling Of Physical Accessibility By Using Floating Car Data And Monte Carlo Simulations

Ertugay, Kivanc 01 September 2011 (has links) (PDF)
The term physical accessibility has widely been used by geographers, economists and urban planners and basically reflects the relative ease of access to/from several urban/rural services by considering various travelling costs. Numerous accessibility measures, ranging from simple to sophisticated, can be found in the GIS based accessibility modeling literature. However, whether simple or sophisticated, one of the fundamental shortcomings of the current GIS-based accessibility measures is that they are generally calculated from a fixed catchment area boundary based on constant traveling costs such as Euclidian (bird-flight) distance costs or transportation network-based average speed costs (e.g. 50 km/h for main streets and 30 km/h for local streets, etc.). Although such deterministic approaches are widely used in GIS-based accessibility modeling literature, they are not realistic, especially due to highly variable speeds in road segments and uncertainty in the accuracy and reliability of the accessibility measures. Therefore, this dissertation provides a new stochastic methodology for GIS-based accessibility modeling process by using GPS-based floating car data and Monte Carlo Simulation (MCS) that could handle variations in traveling costs and consider all possible catchment area boundaries, instead of one average or maximum fixed catchment area boundary. The main contribution of the research is that / the proposed physical accessibility modeling could handle uncertainties in transportation costs, create significant improvement on accuracy and reliability of accessibility measures in terms of catchment area boundaries and support decision makers who are supposed to deal with accessibility, location/allocation and service/catchment area related issues. The proposed stochastic methodology is implemented to a case study on medical emergency service accessibility, in Eskisehir, Turkey and the results of the deterministic and stochastic accessibility models are compared. The main focus of the case study is not to evaluate a specific accessibility condition in a detailed manner but to provide a methodological discussion and comparison between the deterministic and stochastic accessibility modeling process. With the implementation to a case study, it is shown that / the results of the proposed methodology are more realistic than the conventional deterministic approaches.
142

Apleistų pastatų naudojimo modeliavimas darnaus vystymo(-si) aspektu / Modelling of derelict buildings‘ use from the perspective of sustainable development

Antuchevičienė, Jurgita 27 May 2005 (has links)
The decision-making model was developed that allows solving multi-attribute problems of derelict buildings management from the perspective of sustainable development and under uncertainty. The model deals with the problem of developing the derelict buildings’ redevelopment variants and choosing the most rational one. Planning and technical components of an effective model in conformity with the main principles of sustainable development were proposed. The model of the sustainability indicator system for management of derelict buildings was designed. The developed system was applied to multi-attribute decision-making. A comparative analysis of the results was developed. The model was adjusted for modelling and evaluating the rational management of derelict rural buildings in Lithuania. The facilities of GIS for a spatial decision-making were adjusted to the analyzed problem of sustainable revitalization of derelict buildings.
143

A database based information system for artisanal fisheries management : a case study of Moma-Angoche in Mozambique

Vales, Maria Eulália. January 2007 (has links)
Sound management of information and data is an essential cornerstone for efficient and effective decision making. Structured, up to date and easily retrievable data from several heterogeneous sources is often required to effectively manage, monitor and predict resource quantities particularly for depleting resources such as fish. The documentation and management of fisheries data in most developing countries however poses great challenges. The main aim of this study therefore is to design an information system (IS) for Artisanal Fisheries management. The developed IS is supported by a database. Secondary data, from the provincial offices of Moma and Angoche in Mozambique, is used to test and populate the prototype database. The manner in which the database is developed demonstrates how in practice a database can be created as part of an information system. However, due to time restrictions, a complete database for the AF system could not be developed. To accomplish the objectives of the study, a model of the Artisanal Fisheries (AF) system was developed first. Based on standard system development approaches, the key components of the AF system that include; processes, data flows and data stores, were identified. The developed conceptual system was then used to identify critical data stores for the AF system and data models were subsequently developed. A prototype database to support the AF system was then implemented in MS Access. The motivation for this study is as a result of two observations made on information management which are a challenge in artisanal fisheries management in Moma-Angoche. These observations are; (i) the current information system lacks a structured approach and a database to document and archive data/information on the artisanal fisheries subsector; and, (ii) the high proportion of the data/information collected from different sources is not well processed, analyzed and is not user-friendly as yet. The Moma-Angoche Provincial Fisheries office was chosen because it is strategically suitable for research. This has been demonstrated by the amount of socio-economic artisanal fishing census data already collected and by the research on stock marine resources already carried out. As a result, the study area has become a pilot zone of integrated fisheries development projects. During the life cycle of the various projects, and even after their termination, the area remained an important zone where subsequent studies (for example baseline studies) were carried out. Furthermore, the existence of subsequent data available from those studies allows a good opportunity for data comparisons to be made. / Thesis (M.Env.Dev.) - University of KwaZulu-Natal, Pietermaritzburg, 2007.
144

Apleistų pastatų naudojimo modeliavimas darnaus vystymo(-si) aspektu / Modelling of derelict buildings‘ use from the perspective of sustainable development

Antuchevičienė, Jurgita 30 May 2005 (has links)
The decision-making model was developed that allows solving multi-attribute problems of derelict buildings management from the perspective of sustainable development and under uncertainty. The model deals with the problem of developing the derelict buildings’ redevelopment variants and choosing the most rational one. Planning and technical components of an effective model in conformity with the main principles of sustainable development were proposed. The model of the sustainability indicator system for management of derelict buildings was designed. The developed system was applied to multi-attribute decision-making. A comparative analysis of the results was developed. The model was adjusted for modelling and evaluating the rational management of derelict rural buildings in Lithuania. The facilities of GIS for a spatial decision-making were adjusted to the analyzed problem of sustainable revitalization of derelict buildings.
145

A GIS approach for improving transportation and mobility in Iqaluit, Nunavut Territory

Copithorne, Dana 22 December 2011 (has links)
Planning for transportation within northern Canadian communities presents unique challenges, but new research tools offer opportunities for testing potentially innovative solutions that might help improve mobility within these communities. In particular, problem solving has been enriched in recent years by using the spatial modeling methods offered by Geographical Information Systems (GIS). This thesis first reviews various GIS methods before applying one method – the ‘Route Utility Theory’ – to a newly-developed set of metrics for determining the cost of alternate modes of intracommunity transportation. This set of metrics is applied to a data set that represents the trips or journeys made by non-car users in Iqaluit, the capital city of Nunavut Territory. GIS data on roads, walking trails, land contours, and public and residential neighbourhoods are analyzed. The results facilitate comparisons between road options and trail options for improving the movement of people within Iqaluit. Five bus routes were then custom designed and compared using the study’s metrics. The study found that increasing bus and trail options within Iqaluit would provide more efficient options for non-car users. It is argued that the study’s metrics can be adapted for application in other northern communities, and possibly in other isolated and rural communities in different world situations. / Graduate
146

A Fuzzy Based Decision Support System For Locational Suitability Of Settlements / Odunpazari, Eskisehir Case Study

Ercan, Ismail 01 February 2006 (has links) (PDF)
Spatial Decision Making as a branch of decision making science deals with geographically related data in order to achieve complex spatial decision problems. Fuzzy set theory is one of the methods that can be used to come up with these types of problems. On the other hand, Geographical Information Systems (GIS) is one of the most powerful tools that we can use to accomplish spatial decision problems. Selection of the suitable site or land-use for the real estate is also a spatial decision making problem. When we consider the initial dynamics of the suitably located property from the point of view of value and potential we observe that the &ldquo / good location&rdquo / is the dominating factor. This study reports on the development of a kind of decision support system for locational suitability of settlements that integrates the fuzzy set (FZ) theory, a rule-based system (RBS) and GIS. This study is thought as the assistant for the property managers that are buyers and sellers. It can function as the property consultant for the buyers when they are looking for a property to buy and also it helps the real estate agencies to sell their properties. On the other hand, different scenarios of the potential areas according to the different user&rsquo / s preferences are depicted and they are joined and compared with the results of the vulnerability to earthquake hazards&rsquo / of the same area. Odunpazari - Eskisehir area is selected for implementation of the case study because of the data availability. As a result of this study, it can be said that most suitable property changes depending on the people&rsquo / s preferences. In addition, it is seen that most of the buildings that are locationally suitable are highly vulnerable to the earthquake hazards.
147

Conceptions of geographic information systems (GIS) held by senior geography students in Queensland

West, Bryan A. January 2008 (has links)
Geographical Information Systems (GIS) represent one of the major contributions to spatial analysis and planning of the new technologies. While teachers and others have viewed its potential contribution to geographical education as considerable, it has not been known with any certainty whether they present a valuable educational tool that aids geographical education. The value of GIS to geographical education is viewed as depending on a geographical education being, in itself, valuable. Within this context, synergetic focus groups are employed to explore the conceptions of GIS held by 109 secondary school students studying Senior Geography in metropolitan and regional Queensland, Australia. A phenomenographic approach is adopted to identify the six qualitatively different ways, or conceptions, in which the participating students experience GIS as: 1. Maps and a source of maps in geography. 2. Mapping in geography: a way to use and create maps. 3. A professional mapping tool: exceeding the needs of senior geography. 4. Frustrating geography: irksome and presenting many challenges to the student-user. 5. Relevant geography: within and beyond the school experience. 6. A better geography: offering a superior curriculum, and broader geographical education, when contrasted to a senior geography that omits its use. The structural and referential elements of each of these conceptions are elucidated within corresponding Categories of Description. The qualitatively different ways in which the conceptions may be experienced are illustrated through an Outcome Space, comprising a metaphoric island landscape. This structural framework reveals that for the Senior Geography students who participated in this investigation, the extent to which GIS may augment the curriculum is influenced by the nature of students' individual understandings of how GIS manages spatial data. This research project is a response to repeated calls in the literature for teachers of geography themselves to become researchers and for a better understanding of GIS within geography education. It reviews the salient literature with respect to geography and geography education generally, and GIS within geographical education specifically. The investigation has confirmed that qualitatively different conceptions of GIS exist amongst students and that these are not consistently aligned with assumptions about its use and benefits as presented by current literature. The findings of the study contribute to knowledge of the potential educational outcomes associated with the use of GIS in geography education and decisions related to current and potential geography curricula. It provides guidance for future curriculum development involving GIS and argues for additional research to inform educators and the spatial sciences industry about the actual and perceived role of GIS within geography education.
148

Crime analysis and police station location in Swaziland : a case study in Manzini

Tengbeh, Sahr 03 1900 (has links)
Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Criminal activity and police station locations have an inherent geography that needs to be understood in order for crime prevention strategies to be reasonably effective. This study analysed the spatiotemporal pattern of crime in the city of Manzini, in Swaziland, for the period of 2004 and determined suitable locations for future police stations. Four categories of crime were analysed. These were crimes against property, crimes against people, drug related crimes and crimes against public order. Five main analyses were performed namely: overlay analysis, proximity analysis, temporal analysis, morphological analysis, and accessibility analysis. The findings suggest that crimes against property are the most prevalent category of crime in Manzini with a prevalence rate of 84.2%. This category was followed by crimes against people (11.9%), drug related crimes (3.5%), and crimes against public order (0.4%). Landuses associated with transportation experienced the highest amount (22%) of crime in Manzini. There was a strong relationship between incidents of crime and areas with medium to high population density. The proximity analysis revealed that the highest concentration of incidents of crime was between 50 and 100 metres from alcohol serving establishments in Manzini. In a similar analysis, the proximity of incidents of crime to educational institutions was concentrated between 500 and 1000 metres whereas the proximity of incidents of crime to the Manzini police station was dominant between 250 and 500 metres. Of all recorded incidents of crime 87% occurred during the day while 13% occurred during the night. In areas of high-crime concentration such as the bus rank and the Manzini market, it was established that the structural layout of these areas promoted criminal activity. The accessibility analysis showed that seven police stations are necessary to ensure that people do not walk more than 30 minutes to the nearest police station in Manzini. The study concluded that crime prevention strategies would require the intervention of both the police and city planners to be reasonably successful. It also noted that the establishment of accessible police stations would complement the efforts of the police in their endeavour to combat crime in Manzini.
149

[en] ENVIRONMENT CHANGES DETECTION: A PROACTIVE SYSTEM TO MONITOR MOVING OBJECTS / [pt] DETECÇÃO DE MUDANÇAS NO AMBIENTE: UM SISTEMA PROATIVO PARA MONITORAR OBJETOS MÓVEIS

FABIO DA COSTA ALBUQUERQUE 13 February 2017 (has links)
[pt] Sistemas de posicionamento, combinados com tecnologias de comunicação de baixo custo, abrem possibilidades interessantes para implementar aplicações em tempo real que monitoram objetos móveis e que apoiam sistemas de tomada de decisão. Inicialmente, esta dissertação discute requisitos básicos para aplicações proativas de monitoramento em tempo real. Em seguida, propõe uma arquitetura para aplicações proativas que monitoram objetos móveis, explorando a semântica da trajetória e a dinâmica do ambiente. Por fim, fornece um exemplo sobre como uma aplicação que monitora uma frota de caminhões pode se tornar proativa, utilizando notícias sobre condições da malha viária, a partir da publicação de dados em texto não estruturado através da Internet. A dissertação descreve como estruturar e georreferenciar as notícias, utilizando serviços de geocodificação. / [en] Positioning systems, combined with inexpensive communication technologies, open interesting possibilities to implement real-time applications that monitor moving objects and that support decision making. This dissertation first discusses basic requirements for proactive real-time monitoring applications. Then, it proposes an architecture to deploy applications that monitor moving objects, are pro-active, explore trajectory semantics and are sensitive to environment dynamics. Lastly, this dissertation provides an example of how an application that monitors a fleet of trucks can become proactive, using unstructured text information available on Internet focused on road conditions change. The dissertation describes how to structure and geo-reference the text, using available geocoding services.
150

Uma arquitetura orientada a serviços para roteamento personalizado. / A service-oriented architecture for custom routing.

SILVA, Elvis Rodrigues da. 31 July 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-07-31T18:16:44Z No. of bitstreams: 1 ELVIS RODRIGUES DA SILVA - DISSERTAÇÃO PPGCC 2007..pdf: 3374100 bytes, checksum: 70beb2c61d7b1eb969fe1e64941edd84 (MD5) / Made available in DSpace on 2018-07-31T18:16:44Z (GMT). No. of bitstreams: 1 ELVIS RODRIGUES DA SILVA - DISSERTAÇÃO PPGCC 2007..pdf: 3374100 bytes, checksum: 70beb2c61d7b1eb969fe1e64941edd84 (MD5) Previous issue date: 2007-04 / Os sistemas de roteamento vêm se tornando ferramentas bastante úteis recentemente. Eles pretendem ajudar os usuários a encontrar o caminho mais adequado entre dois lugares de acordo com a distância da viagem, o tempo do percurso, e outros critérios. Esta dissertação apresenta uma arquitetura orientada a serviços e propõe um novo algoritmo de busca de rotas chamado Coolest Path. Este algoritmo habilita personalização multi-critério de acordo com a distância da viagem, o tempo, pontos turísticos e a simplicidade do caminho. Além disso, a dissertação propõe restrições a serem acrescentadas aos caminhos calculados: A-autonomy, onde o usuário define uma constante A e o algoritmo provê um caminho com N paradas, uma a cada distância A; e T-autonomy, onde o usuário define uma constante T e o algoritmo provê um caminho com N paradas, uma a cada T unidades de tempo. Essas paradas são realizadas em pontos de interesse (ex. pontos turísticos). Os algoritmos são fornecidos na forma de serviços Web, ou seja, são acessíveis de qualquer dispositivo conectado à Internet: um browser desktop, um celular ou um quiosque turístico localizado em um aeroporto. O serviço de roteamento é uma extensão ao framework iGIS. / Routing systems have become very powerful tools recently. They help users in finding the most suitable path between two places using travel distance, time and others criteria. This dissertation presents a routing system based on service-oriented architecture, which includes the proposal of an innovative algorithm known as coolest path. This algorithm enables multi-criteria personalization by using travel distance, time, points of interest and path simplicity. Moreover, constrained paths are also supported including the implementation of a-autonomy in road networks and the proposal of a new algorithm: t-autonomy, which returns the best path with N stops, such that the travel time between any two consecutive points in the path is not greater than t. These algorithms are implemented as an iGIS extension by using Web services technology.

Page generated in 0.1302 seconds