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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

GIS diffusion in China: theoretical considerations and preliminary case studies. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 2001 (has links)
Kong Yunfeng. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (p. 280-312). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
2

Development, evaluation and application of a geographic information retrieval system

Hu, You-Heng, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2007 (has links)
Geographic Information Retrieval (GIR) systems provide users with functionalities of representation, storage, organisation of and access to various types of electronic information resources based on their textual and geographic context. This thesis explores various aspects of the development, evaluation and application of GIR systems. The first study focuses upon the extraction and grounding of geographic information entities. My approach for this study consists of a hierarchical structure-based geographic relationship model that is used to describe connections between geographic information entities, and a supervised machine learning algorithm that is used to resolve ambiguities. The proposed approach has been evaluated on a toponym disambiguation task using a large collection of news articles. The second study details the development and validation of a GIR ranking mechanism. The proposed approach takes advantage of the power of the Genetic Programming (GP) paradigm with the aim of finding an optimal functional form that integrates both textual and geographic similarities between retrieved documents and a given user query. My approach has been validated by applying it to a large collection of geographic metadata documents. The third study addresses the problem of modelling the GIR retrieval process that takes into account both thematic and geographic criteria. Based on the Spreading Activation Network (SAN), the proposed model consists a two-layer associative network that is used to construct a structured search space; a constrained spreading activation algorithm that is used to retrieve and to rank relevant documents; and a geographic knowledge base that is used to provide necessary domain knowledge for network. The retrieval performance of my model has been evaluated using the GeoCLEF 2006 tasks. The fourth study discusses the publishing, browsing and navigation of geographic information on the World Wide Web. Key challenges in designing and implementing of a GIR user interface through which online content can be systematically organised based on their geospatial characteristics, and can be efficiently accessed and interrelated, are addressed. The effectiveness and the usefulness of the system are shown by applying it to a large collection of geo-tagged web pages.
3

Development, evaluation and application of a geographic information retrieval system

Hu, You-Heng, Surveying & Spatial Information Systems, Faculty of Engineering, UNSW January 2007 (has links)
Geographic Information Retrieval (GIR) systems provide users with functionalities of representation, storage, organisation of and access to various types of electronic information resources based on their textual and geographic context. This thesis explores various aspects of the development, evaluation and application of GIR systems. The first study focuses upon the extraction and grounding of geographic information entities. My approach for this study consists of a hierarchical structure-based geographic relationship model that is used to describe connections between geographic information entities, and a supervised machine learning algorithm that is used to resolve ambiguities. The proposed approach has been evaluated on a toponym disambiguation task using a large collection of news articles. The second study details the development and validation of a GIR ranking mechanism. The proposed approach takes advantage of the power of the Genetic Programming (GP) paradigm with the aim of finding an optimal functional form that integrates both textual and geographic similarities between retrieved documents and a given user query. My approach has been validated by applying it to a large collection of geographic metadata documents. The third study addresses the problem of modelling the GIR retrieval process that takes into account both thematic and geographic criteria. Based on the Spreading Activation Network (SAN), the proposed model consists a two-layer associative network that is used to construct a structured search space; a constrained spreading activation algorithm that is used to retrieve and to rank relevant documents; and a geographic knowledge base that is used to provide necessary domain knowledge for network. The retrieval performance of my model has been evaluated using the GeoCLEF 2006 tasks. The fourth study discusses the publishing, browsing and navigation of geographic information on the World Wide Web. Key challenges in designing and implementing of a GIR user interface through which online content can be systematically organised based on their geospatial characteristics, and can be efficiently accessed and interrelated, are addressed. The effectiveness and the usefulness of the system are shown by applying it to a large collection of geo-tagged web pages.
4

Public commons for geospatial data: a conceptual model /

Sharad, Chakravarthy Namindi, January 2003 (has links) (PDF)
Thesis (M.S.) in Spatial Information Science and Engineering--University of Maine, 2003. / Includes vita. Includes bibliographical references (leaves 93-99).
5

Geographic Literacy and World Knowledge Among Undergraduate College Students

Winship, Jodi M. 03 November 2004 (has links)
To succeed in today'­s globalized world, it is important to understand the places and cultures outside our own. Yet despite the acknowledged need for and importance of a greater understanding of the world, various surveys assessing geographic knowledge have demonstrated the geographic ignorance of people in the U.S. The purpose of this study is to assess the level of geographic literacy among undergraduate college students and to investigate factors that may influence geographic literacy. An on-line survey, adapted from the National Geographic/Roper 2002 Global Geographic Literacy Survey, was administered to a sample of undergraduate students at Virginia Tech. The survey included a geography "quiz" to assess knowledge of geography and world events and a background section to collect information about various factors that may influence the participants' geographic literacy. Over 400 students participated in the study. The data were statistically analyzed using the Mann-Whitney U and Kruskal-Wallis tests for differences in means. Contrary to much of the previous research, the participants in this survey demonstrated a good level of geographic knowledge. The mean score of the geography "quiz" was 81 percent. Some of the factors found to have influence on the scores were gender, international travel, major, fulfillment of Virginia Tech's Area 7 requirement, frequency of news media access, and type of news accessed. Age, academic class, GPA, residency status, junior/high school geography classes, international friends, and knowledge of foreign languages were found to have little or no influence." / Master of Science
6

Designing spatio-temporal information systems : an object-oriented approach

Story, Philip A. January 1996 (has links)
No description available.
7

The Greek GIS community

Assimakopoulos, Dimitris G. January 1997 (has links)
No description available.
8

Supporting spatial orientation| Using resizable icons to visualize distant landmarks on mobile phones

Zhao, Jiayan 28 June 2016 (has links)
<p> Mobile phones have become so popular in navigation. Empirical studies, however, have implied several pitfalls of using these mobile systems. First of all, the small size of the mobile screen fragmentizes the map information so that users have to interact with the display frequently for fear of disorientation. In addition, generated navigation guides with continuous displays of routing information relieves users&rsquo; cognitive load, but the excessive reliance on the displayed spatial information keeps the users being mindless of the environment that impacts their acquisition of spatial knowledge. Later, landmarks as important referents were suggested to help users integrate the current surroundings with further decision points to support their sense of direction and cognitive mapping. But the small display limited users to access the landmarks located out of the view. To address this issue, designs attempt to display distant landmarks at the edge of screen as a way to overcome the aforementioned limits. In order to enhance spatial orientation while using mobile devices, this study introduced an improved design that not only display the direction but also the distance concept of distant landmarks by changing in size as an indicator of the distance from a user&rsquo;s location. Built on this, two kinds of mechanism were designed to present the distance concept by icons of different sizes: one is based on ratio scale that icons change in size continuously based on an established ratio to the actual distance between the user and the distant location. The other mechanism is based on ordinal scale which assigns one of three different sizes to a certain range of distance implying near, middle, and far. A formal user study was carried out to compare efficiency of these two mechanisms in four types of distance comparison tasks. Results show that ordinal icons are more effective than ratio icons in visualizing relative distances between two distant landmarks. But for both mechanisms, users have challenges distinguishing distant landmarks from local landmarks when displayed on screen simultaneously. A further step is to explore some other feasible options of representing distance.</p>
9

Organisation and analysis of spatial data

Williams, Richard David January 1988 (has links)
No description available.
10

A spatial study of aspects of the Roman settlement of Spain through the use of GIS

Massagrande, Federica Ada Nelda Marina January 1995 (has links)
No description available.

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