3D Rendering of Geo-Spatial Data in XML/GML Using Python
3D Rendering of Geo-Spatial Data in XML/GML Using Python.
ABSTRACT
Geographic information (also called geo-information, spatial information, or geospatial information) plays an increasingly important role in our society. Location-based services, applications for urban planning, disaster management systems rely on up-to-date geospatial data.
Geo-spatial data as a major component of every Geographic Information System has been facing many challenges in its use including portability, maintainability, interoperability, accessibility, and unavailability of the digital datasets.
This work proposes a framework for the 3D rendering of Geo-spatial data in XML/GML which are MarkUp Languages that encode Geo-spatial information in the Web.
With our framework, we were able to extract Geo-spatial information from the satellite imagery of an area covered by the Ahmadu Bello University, Zaria, then store this information in a spatially enabled database interfaced with our Python engine which now renders this geospatial information in GML.
The basic idea is to render this geographic information in a unique environment (the Web) that will make this data portable, accessible, maintainable, and interoperable.
The approach reveals interesting results as it was discovered that the framework with a little extension can be adapted to serve geographic data in other XML-base technologies capable of holding geographic information like CityGML, X3D, and KML.
Table of Contents
DECLARATION ………………………………………………………………………………………………………………………. iii
CERTIFICATION……………………………………………………………………………………………………………………… iv
DEDICATION………………………………………………………………………………………………………………………….. v
ACKNOWLEDGEMENT ……………………………………………………………………………………………………………. vi
ABSTRACT …………………………………………………………………………………………………………………………… vii
Table of Contents………………………………………………………………………………………………………………….viii
LIST OF FIGURES …………………………………………………………………………………………………………………….. x
LIST OF TABLES ……………………………………………………………………………………………………………………… xi
LIST OF APPENDICES………………………………………………………………………………………………………………xiii
ABBREVIATIONS, DEFINITIONS, GLOSSARIES, AND SYMBOLS …………………………………………………………xiv
CHAPTER ONE ………………………………………………………………………………………………………………………..2
GENERAL INTRODUCTION…………………………………………………………………………………………………………2
1.1 Background of study ………………………………………………………………………………………………….2
1.2 Research Motivation and Goals…………………………………………………………………………………… 6
1.3 Research Questions……………………………………………………………………………………………………7
1.4 Research Objectives…………………………………………………………………………………………………..8
1.5 Methodology …………………………………………………………………………………………………………… 8
1.6 Contributions to Knowledge………………………………………………………………………………………..9
CHAPTER TWO …………………………………………………………………………………………………………………….. 10
LITERATURE REVIEW……………………………………………………………………………………………………………… 10
2.0 Geo-Spatial Data …………………………………………………………………………………………………….. 10
2.1 Geographic Coordinate System………………………………………………………………………………….. 11
2.3 Geo-Spatial Data Types (SDT) ……………………………………………………………………………………. 12
2.4 Geo-Spatial Data File Format…………………………………………………………………………………….. 14
2.5 Geo-Spatial Data Collection………………………………………………………………………………………. 15
2.6 A Major Problem Associated With Geo-Spatial Data Usage……………………………………………. 16
2.7 The Web as a Major Platform to Enhance Geo-Spatial Data Interoperability ………………………….. 16
2.7.1 Geography Markup Language (GML)…………………………………………………………………… 17
2.7.2 Mechanisms of GML for Data Interoperability ……………………………………………………… 18
2.7.3 Generating GML Data……………………………………………………………………………………….. 23
2.7.4 Visualizing GML Data ………………………………………………………………………………………… 24
2.8 Review of 3D GIS Implementation with the Web’s Markup Language ……………………………… 26
2.9 Relationship between our proposed framework and the prototype reviews…………………….. 30
CHAPTER THREE …………………………………………………………………………………………………………………… 31
SYSTEM DEVELOPMENT…………………………………………………………………………………………………………. 31
3.0 System Requirements……………………………………………………………………………………………….. 31
3.1 Geographic Data in GML……………………………………………………………………………………………. 36
3.0.1 GML Features…………………………………………………………………..
3.0.1 Encoding Geographic Information with GML ………………………….
3.0.2 Structures of GML Documents………………………………………………………………………………….. 40
3.2 Proposed Framework………………………………………………………………………………………………. 36
CHAPTER FOUR ……………………………………………………………………………………………………………………. 48
SYSTEM IMPLEMENTATION ……………………………………………………………………………………………………. 48
4.0 Data Collection ………………………………………………………………………………………………………. 48
4.1 Data Storage………………………………………………………………………………………………………….. 52
4.2 Algorithm used for implementation of the Python Engine …………………………………………….. 54
4.3 Visualization of the Generated GML ………………………………………………………………………….. 55
CHAPTER FIVE………………………………………………………………………………………………………………………. 56
SUMMARY AND FUTURE WORK………………………………………………………………………………………………. 56
5.0 Summary ………………………………………………………………………………………………………………. 56
5.2 Future Work ………………………………………………………………………………………………………….. 57
REFERENCES………………………………………………………………………………………………………………………… 59
INTRODUCTION
This chapter discusses the introductory part of the thesis which includes a background of the study, research motivations, and goals, the research questions for which the thesis attempts to answer, the methodology that is used to answer those questions and finally the summary of the thesis contributes to knowledge.
- Background of study
The World Wide Web has found its application in all spheres of life and studies. Geographic information management and analysis is not an exception to this.
Geography is primarily concerned with location-based phenomena in both manmade and natural realms, why things are located where they are, for example, why people inhabit flood-prone areas, how they are related to historical and present activities, and how to make better plans for the future based on experience gained in the past. (Alan, 2003)
The essence of geography resides in location-related problem solving and decision making. Let us take a look at a few examples. In e-government, location intelligence is used to plan growth, improve public services and share information with citizens.
Governments can employ geo-technology to support public works decisions such as highway and sewer planning.
In municipalities, citizens now have a centralized portal where criminal intelligence information is shared by law enforcement at the local, state, and federal levels-giving law enforcement agencies the insight needed to solve and prevent crimes.
Opening a new store or branch location can cost millions of naira, with payback often calculated in years. Companies can now analyze market demographics, competition, and consumer buying 3 habits across alternative geographies in order to predict events well into the future.
This is especially important in times of economic uncertainty when many companies are deciding whether or not to close or relocate stores or branch locations. In facilities management-locating underground pipes and cables, planning facility maintenance, telecommunication network services, energy use tracking, and planning.
In environmental and natural resources management-suitable study for agricultural cropping, management of forests, agricultural lands, water resources, environmental impact analysis, disaster management, and waste facility site location.
In short, geography helps governments, businesses, organizations, and individuals make better decisions. Geographic Information has become a key issue in location-related problem solving and effective decision making.
The field of Geographic Information Systems (GIS) evolved since the 1960s with the basic aim of improving efficiency and effectiveness in decision making.
A GIS is a system using computers and software to collect, retrieves, store, manipulate, transform, analyze and display data that describe the physical and logical properties of the geographic world. (Hilary M. H., 1994)
The problem of geospatial data portability, maintainability and interoperability and information access has been a major problem in the GIS industry. According to the Open Geo-Spatial Consortium (OGC), the following issues must be solved and promoted
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