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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.
211

A geographical information system's approach to analyzing critical infrastructure interdependencies : a case study at the UBC campus

Cervantes Larios, Alejandro 11 1900 (has links)
In the past few years, the study of critical infrastructures and the interdependencies amongst them in the context of an emergency situation has become a priority for many countries, including Canada. Governments, universities, and private companies all over the world are spending vast amounts of money and effort trying to better understand how infrastructures and humans react in the time stages before, during, and after a disruptive event. Analyzing complex systems such as those formed by infrastructure networks and decision makers is not a simple task and requires a multidisciplinary holistic approach. The field of research in infrastructure interdependencies is fairly new, and lies in the intersection of areas of knowledge such as emergency management, geography, simulation modeling, planning, and safety engineering. Analyzing interdependencies between infrastructure networks is not only a complex problem in terms of its formalization, but also in terms of the intricacy required to test and validate that formalization. Furthermore, identifying and having access to the data necessary to validate the formal system is probably an even more complicated issue to resolve. It is, however, only through the study of these interdependencies that certain failures or weaknesses in the systems can be discovered; weaknesses that could not be studied through the analysis of a single isolated system. Not only is it a challenging task to analyze the interconnections between infrastructure systems, but studying these at moments of stress, when the interdependencies become dynamic, is even more difficult. In this thesis I explore the intersection between three main themes: Critical infrastructure interdependencies, Emergency Management, and Geographical Information Systems (GIS). Furthermore, I analyze the different types of interdependencies between infrastructure systems, I describe some of the challenges that have to be dealt with when modeling interdependencies, and I explore the possibility of modeling and visualizing some of these interdependencies by constructing an Infrastructure Geographical Information System of the UBC campus.
212

Improving road ice prediction through the introduction of GIS generated geographical parameters to an ice forecasting model

Fry, Richard January 2010 (has links)
Network forecasting has traditionally been conducted using survey data collected by field-based surveys of the road network to model the microclimate surrounding the road network. A review of the literature in the subject area identifies that the current methods rely heavily on a field based survey approach. This research examines the premise that these field surveys replaced by modern GIS modelling methods. The research goes on to describe the development of a variety of GIS based methodologies and software for the calculation of geographical parameters for input into the Geographical Road Ice Prediction model and the dissemination of the resulting ice forecast through a web based GIS system. The methods developed are then discussed in relation to a trial conducted in Hampshire in the winter of 2006/7, which test the methods in a real world scenario. The final element to this research is the exploration of a variety of different GIS datasets to test the methodologies developed and investigate the impact of varying the methodologies and data sources on the network forecast for a small locality in the north of Hampshire. Results suggest that a number of the methodological parameters developed could be adjusted without affecting the resulting forecast and therefore improve the efficiency of the modelling process. It also identifies which of the GIS datasets available in the UK produce the best forecasting results. The research concludes that the methodologies developed have successfully helped predict ice formation on road networks without the use of any manual survey data. Moreover, the methods developed can be used in other research fields. In particular, this research has found a more accurate method for modelling building heights from medium resolution IFSAR data, which has resulted in an 11% improvement in building height estimations. Finally, this research goes onto discuss further research and how a more detailed assessment of the methodologies under different climatic and geographical conditions the methods developed, have the potential to replace parts or all of the survey methods currently used in ice prediction surveys.
213

Validação de dados geográficos espaciais em ambiente orientado a objeto / Validation of espacial geographic data in orientaded object environment

Saldanha, Marcus Fabiano Silva January 2005 (has links)
A produção de base cartográfica para os SIG apresenta peculiaridades distintas daquelas produzidas somente para atender os usuários da cartografia. Portanto cartas digitais em formato vetor produzidos em ambiente de CAD devem passar por rigoroso processo de validação geométrica antes de serem usadas por tais sistemas. Este trabalho tem por finalidade apresentar uma metodologia de validação geométrica de dados geográficos para uso em SIG baseada em ambiente orientado a objeto. Pra tanto são apresentados no decorrer do trabalho os principais conceitos relacionados ao assunto, bem como, a descrição da aquisição de dados via digitalização vetorial, as principais fontes de erro oriundas deste processo e o processo de validação em ambiente de CAD. Também é apresentado de forma pormenorizada os conceitos relacionados à tecnologia de banco de dados Orientado a Objeto e o Sistema Gothic, dentro do qual foram realizadas as implementações. Por fim são apresentadas a descrição das rotinas elaboradas e a metodologia desenvolvida, além de resultados obtidos em testes preliminares. Os testes realizados mostram que ocorreram ganhos de produção consideráveis sem que houvesse perda de qualidade. / The production of cartographic base for the SIG presents distinct peculiarities of those only produced to attend the cartographic users. Therefore digital charts produced in vector format in CAD environment must pass for rigorous process of geometric validation before being used for such systems. This work has for purpose to present a methodology of geomettric validation of geographic data for use in SIG based on oriented object environment. For this the main concepts related to the subject are presented during the work, as well as, the description of acquisition of the data by means of vector digitizer, the main deriving sources of error of this process and the process of validation in CAD environment. Also it is presented of detailed form the concepts related to the technology of Oriented Object data base and the Gothic system, which was used for the implementations. Finally the description of the elaborated routines and the developed methodology are presented, beyond some results gotten in preliminary tests. The tests show that considerable profits of prodution had occurred without that had loss of quality.
214

Vyhodnocení populace spárkaté zvěře na Horažďovicku pomocí GIS / Population development of ungulates in Horažďovice region (SW BBohemiaa) by GIS method

Ferdová, Jiřina January 2016 (has links)
The goal of this work is to evaluate the development of population dynamics of cloven-hoofed game in the years 2005 - 2014 and various hunting grounds in the interest area. There are the largest population of roe deer and wild boar at the Horažďovice region. There are also other specific game species - mouflon, sika and fallow deer. The landscape at the Horažďovice region is cultural, widely used for agriculture and it is not varied for cloven-hoofed game. The gamekeeper's statistics are the most important source of data for evaluating the development of population dynamics of this game. There were analyzed the data for the spring fundamental groups, hunting and death in specific game species. The results are processed by using clear tables, graphs and primarily maps created by GIS method.
215

Změny reliéfu dna a objemu VD Fojtka vlivem zanášení / Changes in volume of water reservoir Fojtka due to sediment flux

Vlasák, Tomáš January 2016 (has links)
Sedimentation in dams is a natural process depending on various factors over a period of time. Sediments influence both total capacity of dam's surface and also relief of bottom. This thesis deals with amount of sediment in Fojtka dam and with change of its bottom's relief in past 109 years since its establishment. There was conducted measuring using an echosounder in a boat. Final output derived from this experiment was a point layer including 5500 point items. Subsequently there was executed a measurement of dam's shoreline using GPS device. Data were processed in ArcGIS software, then reduced and edited to be used for interpolation tools of ArcToolbox. In order to select the most accurate interpolation method, there were created validation data, which were compared with interpolated data. The best results have been achieved by interpolation method Kriging and TIN in resolution 0.5 m. Original maps were vectorized for comparison with current condition. Created validation data were compared in order to show accuracy of particular interpolation. The most useful evaluated method for gained data was TIN method in resolution 0.5 m. TIN method was applied in both data sets for 2D and 3D bottom relief visualization and also for calculation of actual water volume and area of water surface of the dam. Difference in bottom's relief of Fojtka dam showed capacity reduction about 6,7 % and reduction of water surface area about 3,2 %. Regular extracting of sediment in reservoir located above the dam causes this relatively small silting ratio.
216

Změny krajinné struktury a jejich příčiny v katastrálním území Ostrožská Lhota

Hyráková, Lucie January 2016 (has links)
This thesis deals with the changes in landscape structure and sets out the causes of the changes in the use of the landscape in the cadastral territory of Ostrožská Lhota. Interest of the territory is located in Zlín region in the District of Uherské Hradiště. The work compares the use of landscape in the period between the years 1836 and 1953, and in the period between 1953 and 2015. For the determination of the status of the last use of the landscape has been used map II. the military mapping from the year 1836 and Ortofotomapa of the Czech Republic from 1953. The current state of the landscape was mapped out in the field, where potential changes were recorded in the current maps. Analysis of the changes of landscape structure was evaluated according to the area of representation of these selected categories of land use: arable land, permanent grassland, orchards and gardens, vineyards, forest stands, water areas, built-up area, recreation areas and other areas. The digitization of maps - exploring map the development of the outputs of the programme have been processed in ArcGIS.
217

A utilização de banco de dados e sistemas de informações geográficas como ferramentas de apoio à análise dos processos de arenização no sudoeste do Rio Grande do Sul

Pizzio, Analberto Tavares January 2007 (has links)
O presente trabalho tem como objetivo principal desenvolver e implantar um sistema de informações utilizando Banco de Dados que permita uma interface com os Sistemas de Informações Geográficas, promovendo e facilitando o acesso dos dados sobre o Processo de Arenização no Sudoeste do Rio Grande do Sul. Para tal utilizou-se como base as informações contidas no Atlas da Arenização do Sudoeste do Rio Grande do Sul, resultado do trabalho do grupo de pesquisa do Departamento de Geografia do Instituto de Geociências da Universidade Federal do Rio Grande do Sul. A área de ocorrência dos areais está localizada no sudoeste do Estado do Rio Grande do Sul, a partir do meridiano de 54º, em direção Oeste, até a fronteira com a República da Argentina e a República Oriental do Uruguai. A degradação do solo nesta área apresenta-se sob forma de areais, ocupando uma longa faixa onde se localizam os municípios de Alegrete, Cacequi, Itaquí, Maçambara, Manuel Viana, Quaraí, Rosário do Sul, São Borja, São Francisco de Assis e Unistalda. No desenvolvimento desse trabalho buscou-se realizar um levantamento acerca dos conhecimentos específicos tais como Modelagem de Dados, Banco de Dados, Geoprocessamento, Sistemas de Informações Geográficas e os Processos de Arenização no sentido de criar uma base conceitual e tecnológica, que possibilite a estruturação do sistema de maneira mais adequada. Desta forma, o desenvolvimento de sistemas de Banco de Dados deve estar baseado em uma metodologia eficaz, a partir da qual são empregados instrumentos específicos de apoio às diferentes etapas do projeto. Sendo assim, a abordagem utilizada foi a representação de dados no modelo relacional, utilizando-se, para tal, o Modelo de Entidade Relacionamento - MER. Este é baseado na percepção do mundo real, constituído por um conjunto de objetos básicos chamados de entidades, relacionamentos e atributos. Tal modelo foi desenvolvido para facilitar a tarefa de projetar banco de dados relacionais, possibilitando à especificação da estrutura lógica geral do mesmo. Seguindo esta metodologia, foi possível modelar e desenvolver um banco de dados contendo as informações importantes do objeto em estudo, a fim de que esses dados pudessem ser acessados futuramente para análise e obtenção de resultados sobre o Processo de Arenização no Sudoeste do Rio Grande do Sul. / The main purpose of the present work is to develop and implement a database information system to interface geographical information systems in order to foster and ease the access to data regarding the process of sand-spreading (in Portuguese, "Arenização") in southwest Rio Grande do Sul state. The southwest Rio Grande do Sul Sandiness Atlas, a work by the research group from the Geography Department of the Geosciences Institute of the Rio Grande do Sul University, was used as the source of information. The occurrence of fields the sand dunes ("Areais") is restricted to the southwest part of the Rio Grande do Sul state, from the 54W meridian, up to the borderline with the Republic of Argentina and the East Republic of Uruguay. The soil wears down throughout the whole area, forming a long strip of sand over the counties of Alegrete, Cacequi, Itaquí, Maçambara, Manuel Viana, Quaraí, Rosário do Sul, São Borja, São Francisco do Assis e Unistalda. During the development of this work, we sought to gather particular understanding about Data Modelling, Database Systems, Geoprocessing, Geographical Information Systems and Process of Sand-Spreading, in order to build a conceptual and technological base to allow the proper arrangement of the system. In this way, the development of a database system must be grounded by an effective methodology, from which particular support tools to the distinct parts of the project are employed. Therefore, the adopted approach was to represent data in the relational model, using the Entity-Relationship Model (MER), which is based on the perception of the real world, made up by a set of basic objects called in entities, relationships and attributes. The model was developed to ease the task of projecting relational database systems, allowing for its own general logical structure specification. Following this methodology, the modelling and development of a database with all the relevant information about the object of study has become possible in such a way that these data may be accessed later on for analyses and evaluation of the process of sand-spreading taking place over southwest Rio Grande do Sul state.
218

Geografický informační systém Grass a jeho využití pro vizualizaci dat - metodická příručka / Grass - GIS and its using for data vizualization

VAŠKOVÁ, Jiřina January 2011 (has links)
This thesis deals with the general issue of geographic information system GRASS distributed under the licence GNU GPL. It introduces the system itself and its possibilities as well as describes the terminology used in the Geography scientific sector. It also can be use as a simple handbook for teaching GIS.
219

An analysis for the determination of the best measure of precipitation for the estimation of bankfull width

SHRESTHA, SURAJ 01 August 2015 (has links)
It has been demonstrated in past studies that drainage area (Ada) and mean annual precipitation depth (Pmean) are significant independent variables for predicting bankfull channel geometry. Bankfull width (Wbf), a particularly useful measure of bankfull channel geometry, is used in hydrology, fluvial geomorphology and stream ecology applications. Since precipitation depth does not generally have a normal distribution over a basin it is reasonable to question whether or not Pmean is the best measure of precipitation across a basin. That is, perhaps the median precipitation depth (P50) or the mean annual precipitation depth at the basin outlet (Poutlet) is more representative of precipitation in a basin. The objective of the study is to see if Pmean, P50, or Poutlet is a significantly better measure of precipitation in a watershed. Along with Ada, each of these precipitation measures was used to develop relationships for predicting Wbf for basins located across the continental U.S. Using several goodness-of-fit statistics i.e., coefficient of determination(R2), Standard error of estimates(SEE) and Akaike Information Criterion(∆AIC), the relationships were compared to determine which one had the greatest predictive strength. Estimates of Pmean, P50, and Poutlet were derived from a precipitation model developed by PRISM. Results from this study tentatively indicate that all three measures of precipitation depth yield models for predicting Wbf that have comparable goodness-of-fit statistics.
220

Participativní GIS v krajinném a územním plánování

Plíhal, Václav January 2013 (has links)
No description available.

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