Linked data: a geographic perspective

291 Pages·2013·9.596 MB·English

by  Dolbear, Catherine, Hart, Glen

Glen Hart • Catherine Dolbear
Boca Raton London New York
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Contents
Preface......................................................................................................................xv
About the Authors ...................................................................................................xix
Chapter 1 A Gentle Beginning..............................................................................1
1.1 What This Book Is About and Who It Is For ............................1
1.2 Geography and the Semantic Web ............................................2
1.2.1 Geographic Information ...............................................2
1.2.2 The Semantic Web .......................................................3
1.3 GI in the Semantic Web .............................................................3
1.4 Examples ...................................................................................4
1.5 Conventions Used in the Book ..................................................5
1.6 Structure of the Book ................................................................7
1.7 A Last Thought about How to Read This Book ........................7
Chapter 2 Linked Data and the Semantic Web .....................................................9
2.1 Introduction ...............................................................................9
2.2 From a Web of Documents to a Web of Knowledge .................9
2.3 Early History and the Development of the Semantic Web ......12
2.4 Semantic Web Benefits ............................................................16
2.4.1 Data Integration ..........................................................16
2.4.2 Data Repurposing .......................................................17
2.4.3 Data Collection, Classification, and Quality Control ...17
2.4.4 Data Publishing and Discovery ..................................18
2.5 How It Works ...........................................................................19
2.6 Recent Trends in the Field .......................................................21
2.7 Summing Up and Signposts to the Next Chapter ....................23
Notes ...................................................................................................23
Chapter 3 Geographic Information .....................................................................25
3.1 Introduction .............................................................................25
3.2 What Is Geographic Information? ...........................................25
3.3 The Many Forms of GI ............................................................26
3.3.1 Geometry ....................................................................26
3.3.1.1 Raster ..........................................................26
3.3.1.2 Vector ..........................................................27
3.3.2 Topology and Mereology............................................28
3.3.3 Textual Representations .............................................29
3.3.3.1 Description ..................................................29
3.3.3.2 Classification ...............................................30
vii
viii Contents
3.3.3.3 Direction .....................................................31
3.3.3.4 Address .......................................................31
3.4 Representations and Uses of GI ...............................................33
3.4.1 Maps ...........................................................................33
3.4.2 Gazetteers ...................................................................35
3.4.3 Terrain Models and Three Dimensions ......................36
3.4.4 Digital Feature Models ...............................................36
3.5 A Brief History of Geographic Information ............................37
3.5.1 A Traditional Story: GI and GIS ................................37
3.5.1.1 Geographic Information Systems ...............37
3.5.1.2 Standards Develop ......................................40
3.5.1.3 The Web ......................................................40
3.5.1.4 Spatial Data Infrastructures ........................41
3.5.2 GI: A History of the Web and Spatial Coincidence ....42
3.5.2.1 Open Government Data ..............................46
3.5.3 The Formal and Informal Together ............................47
3.6 Summary .................................................................................49
Notes ...................................................................................................50
Chapter 4 Geographic Information in an Open World .......................................51
4.1 Introduction .............................................................................51
4.2 Principles .................................................................................51
4.2.1 Semantic Web .............................................................51
4.2.2 Geographic Information .............................................52
4.3 Applying the Semantic Web to GI ...........................................56
4.3.1 Example ......................................................................56
4.3.1.1 Obtain Appropriate Datasets ......................56
4.3.1.2 Load the Data .............................................57
4.3.1.3 Conduct the Spatial Analysis ......................57
4.3.1.4 Observations and Discussion ......................58
4.3.2 Topological Relationships ..........................................59
4.4 Important Observations ...........................................................61
4.5 Summary .................................................................................63
Notes ...................................................................................................64
Chapter 5 The Resource Description Framework ...............................................65
5.1 Introduction .............................................................................65
5.2 RDF: The Purpose ...................................................................65
5.3 A Word about Identity .............................................................66
5.4 The RDF Data Model ..............................................................67
5.5 RDF Serialization ....................................................................71
5.5.1 RDF/XML ..................................................................71
5.5.2 Turtle ..........................................................................75
Contents ix
5.5.3 N-Triples .....................................................................76
5.5.4 RDFa ..........................................................................76
5.6 RDFS .......................................................................................78
5.6.1 Concepts and Instances: Instantiation and
Hierarchy in RDFS .....................................................78
5.6.2 Vocabularies and Ontology ........................................78
5.6.3 RDFS Syntax: Classes and Properties .......................79
5.6.4 Subproperties, Domain, and Range ...........................80
5.6.5 RDF Containers and Collections................................80
5.6.6 RDFS Utility Properties .............................................81
5.7 Popular RDFS Vocabularies ....................................................82
5.7.1 Geo RDF ....................................................................83
5.8 RDF for the Thinking Geographer ..........................................84
5.9 Summary .................................................................................85
Notes ...................................................................................................85
Chapter 6 Organizing GI as Linked Data ...........................................................87
6.1 Introduction .............................................................................87
6.2 Identity: Designing and Applying Universal Resource
Identifiers .................................................................................87
6.3 Identity: Names........................................................................90
6.4 Geometry .................................................................................92
6.5 Classification ...........................................................................94
6.6 Topology and Mereology .........................................................94
6.6.1 Topology .....................................................................95
6.6.1.1 Region Connection Calculus 8 and
OGC Properties ..........................................95
6.6.1.2 Non-RCC8 or OGC Topology ....................97
6.6.2 Mereology ................................................................100
6.6.3 Network Topology ....................................................101
6.6.3.1 Links and Node Network Model ..............104
6.7 Summary ...............................................................................106
Notes .................................................................................................106
Chapter 7 Publishing Linked Data....................................................................107
7.1 Introduction ...........................................................................107
7.2 Linked Data Principles ..........................................................107
7.3 Making URIs Dereferenceable or Slash versus Hash ...........108
7.3.1 Slash or 303 URIs ....................................................108
7.3.2 Hash URIs ................................................................108
7.3.3 Slash versus Hash .....................................................109
7.4 Linked Data Design ...............................................................109
7.4.1 Step 1: Decide What Your Linked Data Is About ....109
7.4.2 Step 2: Look at the Current GI Data ........................111