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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.
1

Geospatial data sharing in Saudi Arabia

Lee, Donald C. January 2003 (has links)
This research started with a realization that two organizations in Saudi Arabia were spending large amounts of money, millions of dollars in fact, in acquiring separate sets of geospatial data that had identical basemap components. Both the organizations would be using the data for similar engineering purposes, yet both would be independently outsourcing the data gathering. In all probability, resources are being wasted through two organizations each developing and operating stand-alone geographic information systems and then populating the databases with geospatial data obtained separately. Surely with some cooperation, a shared database could be established, with a diffusion of economic benefits to both organizations. Preliminary discussions with representatives from both the organizations revealed high levels of enthusiasm for the principle of sharing geospatial data, but the discussions also revealed even higher levels of scepticism that such a scheme could be implemented. This dichotomy of views prompted an investigation into the issues, benefits and the barriers involved in data sharing, the relative weight of these issues, and a quest for a workable model. Sharing geospatial data between levels of government, between governmental and private institutions, and within institutions themselves has been attempted on large and small scales in a variety of countries, with varying degrees of accomplishment. Lessons can be learned from these attempts at data sharing, confirming that success is not purely a function of financial and technical benefits, but is also influenced by institutional and cultural aspects. This research is aimed at defining why there is little geospatial data sharing between authorities in Saudi Arabia, and then presenting a workable model as a pilot arrangement. This should take into account issues raised in reference material; issues evidenced through experience in the implementation of systems that were configured as independent structures; issues of culture; and issues apparent in a range of existing data sharing arrangements. The doubts expressed by engineering managers towards using a geospatial database that is shared between institutions in Saudi Arabia have been borne out by the complexity of interrelationships which this research has revealed. Nevertheless, by concentrating on a two party entry level, a model has been presented which shows promise for the implementation of such a scheme. The model was derived empirically and checked against a case study of various other similar ventures, with a consideration of their applicability in the environment of Saudi Arabia. This model follows closely the generic structure of the Singapore Land Hub. The scalability of the model should allow it to be extended to other, multi-lateral data sharing arrangements. An alternative solution could be developed based on a Spatial Data Infrastructure model and this is suggested for ongoing investigation. Major unresolved questions relate to cultural issues, whose depth and intricacy have the potential to influence the realization of successful geospatial data sharing in the Kingdom of Saudi Arabia.
2

GIS for spatial decision-making

Vlado, Veldic 24 November 2005 (has links)
Please read the abstract in the section 00front of this document / Dissertation (MSc)--University of Pretoria, 2001. / Geography, Geoinformatics and Meteorology / MSc / Unrestricted
3

Geographical Information System (GIS) web applications for data visualization of Drinking Water pipelines

Shekhawat, Pururajsingh 08 August 2018 (has links)
Robust decision support tools that aid water utilities to make informed, swift and precise decisions are becoming the need of the hour. Application of sophisticated models to aid the process of condition assessment and risk analysis on water pipelines have been limited owing to the lack of scalability, inability to incorporate external open source datasets and mathematically complicated output results. Interactive visualization of resultant model output is the key element in extracting valuable information to support decision making. This thesis presents a framework for visualization of data related to drinking water pipelines. Critical components of strategic, tactical and operational level decision making are explored in context with data presentation and information depiction. This thesis depicts various aspects of developing GIS web applications and their important functionalities for query and visualization of data. Multiple facets of data storage, standardization and application development are highlighted in this document. Publishing of application geo processing services in web environment is done through Virginia Tech enterprise geodatabase. Risk assessment and Performance models developed by a utility are projected in the application environment through help of widgets. Applications are coded into links on a Drupal website (www.pipeid.org) for model dissemination and utility engagement purposes. / Master of Science / Drinking water supply network primarily consists of pipelines, pumping stations, reservoir basins and treatment plants. Water pipelines are routinely inspected to check their condition and maintain appropriate water quality. Management of these subsurface assets should be given prime importance for maintaining high standards of services at acceptable cost to customers. An integral step in accomplishing this task is to view pipeline network in a geographic map. Different factors affecting pipeline condition are displayed on the map in the form of individual layers. Such real-world problems are analyzed with the help of Geographical Information System (GIS) tools that incorporate spatial features with tabular information. Moreover, interpretation of raw data into meaningful insights and distribution of allocated knowledge to all the concerned parties can be efficiently accomplished using rich internet applications. This thesis presents a framework to use GIS tools for developing web applications using raw data samples from contacted water utilities. Sample web applications are created and discussed in the form of case studies. Also, the challenges in water utility sector with respect to utilizing GIS tools for supporting daily decision-making processes is highlighted in this document. The recommendation to improve the suggested framework and adding more functionalities to developed applications are presented at the end with references.
4

Desenvolvimento de um algoritmo para o traçado do divisor de águas de uma bacia hidrográfica em programas que utilizam Sistemas de Informações Geográficas (SIG) / not available

Cordovil, Sérgio Augusto de França 16 August 2001 (has links)
Este trabalho trata da organização de um algoritmo, sem preocupação com a linguagem de programação que possa ser utilizada, para desenvolver um método para o traçado da linha divisória de uma bacia hidrográfica, para aplicações em SIG. O método escolhido foi o de análise dos oitos pixels à volta de um pixel já pertencente ao divisor, constituindo uma variação do processo conhecido como D8 (determinístico dos oito vizinhos), que só é possível ser aplicado em sistemas do tipo raster. A partir dessa análise desenvolveu-se uma metodologia para a definição do próximo pixel que pertencerá ao divisor de águas da bacia. A avaliação do algoritmo foi feita utilizando-se um mapa fictício, criado para incluir as mais prováveis dificuldades encontradas na definição do divisor de uma bacia através de programa computacional. O traçado obtido, acompanhando as etapas lógicas do algoritmo, mostrou-se adequado quando comparado com a linha divisória da bacia traçada manualmente. Um mapa digitalizado a partir de rede local real é utilizado como exemplo de aplicação do algoritmo desenvolvido. / This work is about the organizing of an algorithm, without any regard with the programming language that may be used, in order to develop a method for delineation of watershed boundaries, for GIS applications. The method chosen was the analysis of eight pixels that surround another pixel belonging to the watershed, being a variation of the process known as D8 (deterministic of the eight neighbors), which can only be applied in raster systems. Considering this analysis, a methodology was developed for establishing the next pixel that will belong to the watershed. The algorithm evaluation was done with a fictitious map, created to include the most probable difficulties in establishing the divisor of a watershed through a computer program. The obtained line, following the logical steps of the algorithm, was suitable when compared with the dividing line of the watershed done manually. A digital map of a real place is used as an example of application of the developed algorithm.
5

Planning for Marine Protected Area - Case Study for Guishan Island

Shen, Cheng-Han 17 February 2011 (has links)
With the rapid development of the coastal environment and advances in fishing technology, marine biodiversity and fishery resources are decreasing dramatically. Therefore, each state is now focusing on conserving the marine environment. Planning Marine Protected Areas is one of the simplest and most efficient ways to do this. In recent years, researches have been conducted on Marine Protected Areas around the world. The government and academic fields in Taiwan also has started to value its surrounding marine environment. However, literature on the Marine Protected Areas in Taiwan has focused on policy and management, not so much on planning and zoning strategies. Therefore, this study uses the Geographic Information System (GIS) to simulate the planning and zoning process. This research set principles and zoning framework for Marine Protected Areas in Taiwan based on case studies and spatial analysis techniques. This study uses Gueishan Island in Yilan County as case study since the unique geographical environment of Gueishan Island provides potentiality to set Marine Protected Areas. In this study, it is suggested that "hot spring resources", "cetacean resources", and "fisheries resources" are the main protected objectives. The zoning strategies, management guidelines and recommendations are provided in this study based on these three protected objectives. According to the GIS simulation process, using the spatial analysis techniques is one of the possible efficient methodologies to plan and zone the Marine Protected Areas. With supplementary data and information, the results can be discussed more specifically in the further study. In addition, techniques of visualization during the MPAs zoning process can be a easier way for various stakeholders to understand, and to strengthen mutual communication, thereby reducing disputes to create successful Marine Protected Areas.
6

Vulnerability Assessment of an Island City with Respect to Pre-dicted Climate Change: Case Study of Makung City

Yeh, Cheng-chung 13 September 2012 (has links)
¡@¡@The isolation, separation, and self-contained characteristics of island environ-ments form the unique systems of ecology, culture, and landscape. Simultaneously, characteristics such as a lack of available area, high population density, and depend-ence on imports cause high vulnerability and low resilience in these isolated islands. There are 11 islands around Taiwan. Penghu is one of the islands in this area with the highest density. Under the impact of climate change, the vulnerability and the adapta-tion of the island¡¦s city may be affected. Therefore, Makung City served as a base for this study, which uses field observations and the collection of relevant literature, fol-lowed by spatial analysis methods and vulnerability assessment model analysis to de-termine the vulnerability of Magong City. The study¡¦s results and recommendations could provide a basis for policy on the island with respect to spatial planning and management. ¡@¡@To determine the sources of vulnerability on the island, vulnerability indicators can distinguish between the environment and society. However, up to now, we have not considered the difference between the islands near Taiwan. Therefore, the gov-ernment could not provide basic data to assess vulnerability. However, according to the limiting data of the vulnerability assessment results, the neighborhoods near the Makung port are in a high vulnerability area. If climate change continues with a sea level rise and storm surges, it may impact buildings near the coastal area of Makung City. In this study, the weight of vulnerability indicators was built by equal concep-tion to analyze the island¡¦s vulnerability wholly. Therefore, vulnerability research could try to build weight of island vulnerability in the future.
7

The Review and Prospect of Integrated Coastal Zone Management¡GCoastal Areas of Kaohsiung County as the Case

Shang, Rong-Kang 26 September 2000 (has links)
The coastal zone including coastal waters and littoral zone are influenced by the interactions between sea and land, and the resources of coastal areas have significant functions and values whatever the regards of nature ecology, industry development, transportation, tourism, national defense, and academic research. Following the population growth, economic advancement, and the change of industry, the land use of coastal zone is more diverse and complex. The incompatible between development and marine environment was happened sometimes. In order to solve the conflicts of coastal resources multiple use and mitigate the negative effects by human activities, integrated coastal zone management was become the most important way for sustainable using the sea. ¡§Integrated Coastal Zone Management (ICZM)¡¨ is a resource management system applying the process of integration, connection, and interaction, to analyze the complicated management problem at coastal areas. It is also a framework of principles and methodology for identification of important environmental priorities and allocation of scarce resources. It is an integrated management planning process emphasizing the comprehensive aspect to achieve the sustainable development of the coastal zone. Because the laws and regulations about land planning and coastal zone management is under legislation and the ¡§Coastal Zone Management Plan¡¨ of Kaohsiung County is not accomplished, the research attempts to understand the future development concept and direction about coastal areas in Kaohsiung County according to ¡§Kaohsiung County Comprehensive Development Plan¡¨. The research formulates some phenomena at present involving artificial construction causing coastal erosion, making land destroying the ecology, development project standing, development location overlapping, project contents competing each other, objective scale too large, disregard environmental sensitive areas, using a lot of hard structures, etc. Furthermore, we survey the planning and management of coastal zone through the aspects of integration among sectors, between the land and the water sides of the coastal zone, among levels of government, and among disciplines. Synthesizing the discussions of research, we can find the major problem of coastal zone management at Kaohsiung County is not lacking of planning project, instead of having too many but the implement result is not satisfactory. It is perceived that investigating and evaluating of the resource supply and the user demand at advance planning process was insufficient. Besides, it didn¡¦t have a comprehensive development plan which thinks about coastal environment from the first to be a basis of integration and coordination the various land use. Expecting the future coastal zone development and management, the responsible agency and project proponent can discard the departmental egoism, prior consider the integrated environment, proceed to communication, coordination, and integration continuously in search of a common consensus and vision. Only if that, the coastal zone development can be sustainable.
8

Determining transit impact on Seoul office rent and land value: an application of spatial econometrics

Kim, Jin 17 February 2005 (has links)
This study posits that there may be a systematic bias in measuring the transit’s endogenous impact on land values in a built up area due to discrimination by location in the city. Studies of transit value-added effect report mixed results about the capitalization of station proximity. The question is not whether a transit station influences nearby land values, but how and where location determines the impacts. Examining 731 office rentals and land values in Seoul, this study finds that value premium over better accessibility to a station decays with increasing distance from the central business district (CBD) and significantly depends on the development density of the station area. Overall, station benefits seem to exist in Seoul, but they look more notable in centers with higher centrality. This makes a hierarchy of regression coefficients for station proximity by location, i.e. the beta in the CBD is the highest and those in the subcenters are next, while that in other areas is the lowest. Study findings imply that the potential of more compact and denser developments within station areas seems higher in a dense inner city, providing evidence for the concept of ‘compact city.’ Questions concerning model specification in the hedonic approach are raised: in research sampled heavily from the suburbs, the coefficient may be underestimated where this benefit actually exists. Also, due to the incongruence of station area with station value-added area, using a dummy variable seems intrinsically risky. This study shows that estimation with spatial models outperforms OLS estimation in the presence of spatial autocorrelation. Also, there is a strong spatial autocorrelation even in the SAR residuals where the omission of key variables still influences the estimation. Overall, spatial lag and error term variables greatly improve the fitness of regression equations; however, the latter seemed more useful than the former in this study. One thing to note is that the latter seems more sensitive to the choice of weight matrix than the lag variable. There may exist a unique weight scheme proper for the data structure which cannot be known in advance.
9

Spatial analysis modeling for marine reserve planning¡Ðexample of Kaomei wetland

Chen, Chun-te 16 July 2008 (has links)
It is an internationally acknowledged that marine protected area (MPA) is an important measure for maintaining biodiversity and rescuing endangered species. MPA can also effectively inhibit human interferences such as development and pollution discharge. The establishment of MPA is possible to fulfill the goal of sustainable management, which is to conserve marine habitat for an integrative ecosystem and a higher biodiversity. However, how to design an effective MPA remains an important research issue to be explored. In order to grasp the spatial distribution of the ecological data in the study area, the current research uses spatial interpolation tool, Kriging, provided by the Geographic information system (GIS) software. Then three spatial analytical models have been developed based on integer programming techniques. It is guarantee that all three models can find the global optimal solutions for the best protective area partitions. This quantitative approach is more efficient and effective compared to the qualitative methods in many aspects. The models are able to preserve the maximum ecological resources under the limited spatial area. Besides, the model formulation can be adjusted from different environmental impact factors to fulfill the requirements of users. The case study of the research is to design a MPA for Kaomei wetland. However the spatial analytical models developed in this research can also be applied to protected area design in land area.
10

DETERMINING FACTORS THAT CONTRIBUTE TO NONPOINT SOURCE POLLUTION IN THE LOWER KENTUCKY WATERSHED

Wermuth, James A. 01 January 2007 (has links)
The water quality in the United States has greatly improved since the implementation of the Clean Water Act (CWA) in the early 1970s. Unfortunately, the Clean Water Act only addresses one kind of water pollution, point source pollution. The major problem that is present in the degradation of todays water quality has to deal with nonpoint source pollution. Agriculture is commonly regarded as the leading contributor to nonpoint source pollution in the United States. This study uses two analytical tools to try to determine the significant factors in the transport of pollutants in the Lower Kentucky Watershed, located in central Kentucky. Spatial analysis (GIS) coupled with the statistical analysis (SAS), allowed for significant factors to be identified within a small proximity of sampling sites throughout the watershed. The results suggest that although agriculture is commonly regarded as the largest contributor to nonpoint source pollution, other factors outside of agriculture were also found to be significant, such as resident land use and rainfall. The results generated from this study suggest that land managers in communities throughout the watershed should analyze agricultural factors, as well as, factors outside of agriculture, in an effort to protect their communities water quality.

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