Abstract ¡§Web GIS¡¨ is a Geographic Information Systems¡]GIS¡^ operating on the Internet. Web GIS is very popular in the world now. This 2D web GIS can¡¦t display real world spatial information in three dimension. Virtual Reality (VR) is a fancy technology, which can display real world objects in 3D and is able to walk or fly through in this virtual world. Virtual Reality Modeling Language¡]VRML¡^can be used to construct local terrain and structures in 3D on the internet. In order to use geographic coordinates in the VRML, GeoVRML was developed for GIS purposes. This research tries to integrate the tools of 2D web GIS, VRML and GeoVRML into a 3D web GIS. Concept of multi-view is used for this 3D web GIS, which combines a plan view, a model view and real view in a web page. The function of the plan view is to display 2D map and query attributes. The model view and real view are used to display 3D objects and link with database. However, the real view provides more object details in content and texture. This study tried to transform 2D polygons of the manmade structures into VRML and GeoVRML format without using specific software tools. The transformed 3D buildings are independent objects, which can link with database. The ways of creating terrain in GeoVRML are also discussed. A new node in the GeoVRML is suggested. A simple 3D spatial analysis is also explored. Finally, the campus of our university ( National Sun Yat-sen University ) was used as an example for 3D web GIS. The orthophoto of the IKONOS satellite image and 40m digital terrain model data were used. The interaction among plan view, model view and real view were also designed. A database was successfully linked with model view and real view. The calculation of 3D spatial distance between two points was demonstrated. This 3D web GIS is proved to be a 3D GIS with capabilities of 3D data display, query and 3D spatial analysis.

GIS (Geographic Information Systems) is gradually mature on the Internet, and the applications of the GIS, such as: living, entertainment, traffic, environment etc., are more extensive. People are very easy to get useful spatial information from Web GIS. SVG (Scalable Vector Graphics) was initiated by W3C (World Wide Web Consortium), it is an XML (eXtensible Markup Language)-based two-dimensional vector graphics standard on the internet. It is suitable to be used on the Web GIS. The research focuses on XML-based Web GIS including: spatial information and attribute data. The process to create a SVG system is discussed. Besides to write a software code for implementing a SVG system as a Web GIS, some functions were added to the system to promote the operating efficiency. Finally, two query applications were set up. One is Tapeng Bay to display fundamental setting up process and the other is Taipei school information query system to test the functions for SQL and statistical information. Keywords: Web GIS, XML, SVG, DOM

<p>This project was aimed at critically analyzing the use of web geographical information system (GIS) applications in local government, and problems associated with the design, development, and implementation of web mapping applications in the case study of the municipality of Gävle, Sweden. The project included a scientific and thorough analysis of options for developing web GIS applications by using ESRI GIS software technologies. During this research project, the ESRI GIS software tools and packages were used to perform a comprehensive system analysis of the proposed web mapping application, to gain a better understanding of the available methods of map document and web GIS application performance optimization, and finally to develop a web mapping application prototype for the web map of the municipality of Gävle. The research results include the guidelines for preparing map documents to be published, optimizing ESRI ArcGIS Server web mapping applications performance, and some possible ways of customizing user tools and a user interface by using the Microsoft Visual Studio framework. This study proves that ESRI web-based GIS products provide viable tools for web mapping application design, development, and customization. The developed ArcGIS Server based web mapping application can be optionally improved and then be used instead of existing ESRI ArcIMS-based application in the municipality of Gävle.</p>

The growing necessity for meaningful climate change response has encouraged the development of global warming mitigation and adaptation initiatives. Urban solar energy generation is one opportunity that has been investigated by numerous cities through various solar potential Web-applications. However, as solar feasibility can vary considerably across a small geographic area due to variations in local topography and feature shading, there is no one-size-fits-all solution to be implemented. This thesis investigates how a Web-based spatial decision support system (SDSS) can enable non-experts to explore urban solar feasibility and, to a lesser extent, issues related to urban heat. First, a conceptual framework is developed that investigates the linkages between SDSS, Web technologies, public participation, volunteered geographic information, and existing green energy initiatives. This framework identifies the relevance between these fields of study as well as a number of opportunities for improving on past work and taking advantage of new technical capabilities. Second, in order to test the opportunities identified, SunSpot was developed. This Web-SDSS investigates rooftop solar feasibility as well as land cover and surface temperature dynamics relating to the urban heat-island effect in Toronto, Ontario, Canada. A number of solar resource datasets were developed in order to facilitate the decision making capabilities of SunSpot. This was done using a combination of different topographical data sources, atmospheric data, and a raster-based irradiance model called Solar Analyst. Third, a number of in-person workshops were conducted to obtain feedback on SunSpot’s usability and ability for users to understand the visual layers and results. Finally, this feedback was analyzed to identify the successes and challenges of SunSpot’s capabilities and design. This revealed a number of recommendations for further development of SunSpot, as well as opportunities for future research relating to the development of local scale solar resource data and the development of similar Web-SDSS applications.

This project was aimed at critically analyzing the use of web geographical information system (GIS) applications in local government, and problems associated with the design, development, and implementation of web mapping applications in the case study of the municipality of Gävle, Sweden. The project included a scientific and thorough analysis of options for developing web GIS applications by using ESRI GIS software technologies. During this research project, the ESRI GIS software tools and packages were used to perform a comprehensive system analysis of the proposed web mapping application, to gain a better understanding of the available methods of map document and web GIS application performance optimization, and finally to develop a web mapping application prototype for the web map of the municipality of Gävle. The research results include the guidelines for preparing map documents to be published, optimizing ESRI ArcGIS Server web mapping applications performance, and some possible ways of customizing user tools and a user interface by using the Microsoft Visual Studio framework. This study proves that ESRI web-based GIS products provide viable tools for web mapping application design, development, and customization. The developed ArcGIS Server based web mapping application can be optionally improved and then be used instead of existing ESRI ArcIMS-based application in the municipality of Gävle.

A Web GIS system has a major issue of serving the map data to the client applications. Since most of the GIS services provide their geospatial data as basic image formats like PNG and JPEG, constructing those images and transferring them over the internet are costly operations. To enhance this inefficient process, various approaches are offered. Caching the responses of the requests on the client side is the most commonly implemented solution. However, this method is not adequate by itself. Besides caching the responses, predicting the next possible requests of the client and updating the cache with the responses for those requests provide a remarkable performance improvement. This procedure is called &ldquo / prefetching&rdquo / . Via prefetching, caching mechanisms can be used more effectively and efficiently. This study proposes a prefetching algorithm called Retrospective Adaptive Prefetch (RAP). The algorithm is constructed over a heuristic method that takes the former actions of the user into consideration. This method reduces the user-perceived response time and improves users&rsquo / navigation efficiency. The caching mechanism developed takes the memory capacity of the client machine into consideration to adjust the cache capacity by default. Otherwise, cache size can be configured manually. RAP is compared with 4 other methods. According to the experiments, this study shows that RAP provides better performance enhancements than the other compared methods.

Information technologies have achieved an important role in archaeology. The management, research and exchange of the large amount of data gathered from archeological sites needs the tools of information technologies. The web based GIS combines the advantages of both GIS and the Internet technologies. This system can be used as a tool that helps to support the management of information for archaeological sites and provides support functions for specialists.This web based system can hold many types of archaeological site data from small excavation campaigns to large sites. The system consists of a relational database, a web server, and a GIS mapping server. Google Maps Server is used as a GIS mapping server in this study. The client computers require only the availability of a proper browser that supports javascript and ajax technologies. With this system, Google Maps can be used as an archaeological research tool for everybody interested in archaeology. In a general, everybody can reach the system using their web browsers in order to search and retrieve information regarding archaeological sites. This system also enables specialists to upload, search and share archaeological data. The aim of this study is to provide easy and simple access to the GIS related archaeological site information in Turkey, using a web based and user friendly interface and share the information the information with specialists all over the world.

The growing necessity for meaningful climate change response has encouraged the development of global warming mitigation and adaptation initiatives. Urban solar energy generation is one opportunity that has been investigated by numerous cities through various solar potential Web-applications. However, as solar feasibility can vary considerably across a small geographic area due to variations in local topography and feature shading, there is no one-size-fits-all solution to be implemented. This thesis investigates how a Web-based spatial decision support system (SDSS) can enable non-experts to explore urban solar feasibility and, to a lesser extent, issues related to urban heat. First, a conceptual framework is developed that investigates the linkages between SDSS, Web technologies, public participation, volunteered geographic information, and existing green energy initiatives. This framework identifies the relevance between these fields of study as well as a number of opportunities for improving on past work and taking advantage of new technical capabilities. Second, in order to test the opportunities identified, SunSpot was developed. This Web-SDSS investigates rooftop solar feasibility as well as land cover and surface temperature dynamics relating to the urban heat-island effect in Toronto, Ontario, Canada. A number of solar resource datasets were developed in order to facilitate the decision making capabilities of SunSpot. This was done using a combination of different topographical data sources, atmospheric data, and a raster-based irradiance model called Solar Analyst. Third, a number of in-person workshops were conducted to obtain feedback on SunSpot’s usability and ability for users to understand the visual layers and results. Finally, this feedback was analyzed to identify the successes and challenges of SunSpot’s capabilities and design. This revealed a number of recommendations for further development of SunSpot, as well as opportunities for future research relating to the development of local scale solar resource data and the development of similar Web-SDSS applications.

No description available.

Regulated rivers provide opportunities to improve habitat quality by managing the times, locations, and magnitudes of reservoir releases and diversions across the watershed. To identify these opportunities, managers select priority species and determine when, where, and how to allocate water between competing human and environmental users in the basin. Systems models have been used to recommend allocation of water between species. However, many models consider species’ water needs as constraints on instream flow that is managed to maximize human beneficial uses. Many models also incorporate uncertainty in the system and report an overwhelmingly large number of management alternatives. This dissertation presents three new novel models to recommend the allocation of water and money to improve habitat quality. The new models also facilitate communicating model results to managers and to the public. First, a new measurable and observable habitat metric quantifies habitat area and quality for priority aquatic, floodplain, and wetland habitat species. The metric is embedded in a systems model as an ecological objective to maximize. The systems model helps managers to identify times and locations at which to apply scarce water to most improve habitat area and quality for multiple competing species. Second, a cluster analysis approach is introduced to reduce large dimensional uncertainty problems in habitat models and focus management efforts on the important parameters to measure and monitor more carefully. The approach includes manager preferences in the search for clusters. It identifies a few, easy-to-interpret management options from a large multivariate space of possible alternatives. Third, an open-access web tool helps water resources modelers display model outputs on an interactive web map. The tool allows modelers to construct node-link networks on a web map and facilitates sharing and visualizing spatial and temporal model outputs. The dissertation applies all three studies to the Lower Bear River, Utah, to guide ongoing habitat conservation efforts, recommend water allocation strategies, and provide important insights on ways to improve overall habitat quality and area.