Contents Abstract i Acknowledgements iii List of Figures ix List of Tables xi List of Listings xiii List of Abbreviations xv List of Terms and Definitions xvii 1 Introduction 1 1.1 The Need for an Interoperable Sensor Infrastructure in Disaster Management 1 1.2 Challenges for Integrating Sensors with the Sensor Web 4 1.3 Research Objectives 7 1.3.1 Out of Scope 8 1.3.2 Research Questions 9 1.4 Research Methodology 10 1.5 Chapter Overview 12 2 Context of this Research 17 2.1 From Heterogeneous Sensors to the Sensor Web 17 2.2 Related Approaches for Bridging Between Sensors and Applications 19 2.2.1 Middleware for Sensor Network Management Systems 20 2.2.2 Middleware for Sensor Web Infrastructures 22 2.2.3 Sensor Web Portals 25 2.2.4 Frameworks for Internet of Things/Web of Things 26 2.3 Standards for Sensor Communication 27 2.4 The Sensor Web Enablement Framework of Specifications 30 2.4.1 Introduction to OGC's Sensor Web Enablement Initiative 30 2.4.2 SWE Information Model 32 2.4.3 SWE Interface Model 36 2.4.4 Sensor Web Enablement Projects and Applications 43 2.5 The Semantic Sensor Web 47 3 Use Cases for an On-the-fly Integration of Geosensors 53 3.1 The Wupperverband and its Sensor Web Deployment 53 3.2 Use Case: Flood Monitoring 58 3.3 Use Case: Forest Fire Risk Assessment 61 3.4 Use Case: Oil Spill Monitoring 62 4 Requirements for a Sensor Plug & Play Paradigm on the Sensor Web 67 4.1 Requirements for a Publish/Subscribe Mechanism 67 4.2 Requirements for a Generic Driver Mechanism for Sensors 69 4.3 Requirements for a Matchmaking Mechanism 71 5 Approach for the Automated On-the-fly Integration of Geosensors 75 5.1 An Intermediary Layer for the Geosensor Infrastructure Stack 76 5.1.1 Interactions on an Intermediary Layer Between Sensors and the Sensor Web 77 5.1.2 The Sensor Bus - A Realization of the Intermediary Layer 83 5.2 A Generic Driver Mechanism based on Sensor Interface Descriptors 92 5.2.1 Overview of the Sensor Interface Descriptor Concept 92 5.2.2 Encapsulation of the Sensor Interface Descriptor within SensorML 94 5.2.3 Description of Sensor Addressing 97 5.2.4 Description of Sensor Protocol 98 5.2.5 Description of Data Processing 100 5.2.6 Description of Sensor Output Metadata 102 5.2.7 Description of Sensor Commands 103 5.3 A Tool for the Creation of Sensor Interface Descriptors 105 5.4 A Mechanism for the Semantic Mediation between Sensors and Services 109 5.4.1Semantic Mediation with Sensor Bus Components 110 5.4.2 Creation of Ontological Sensor Descriptions 111 5.4.3 Semantic Matchmaking 111 5.4.4 Conversion between Advertised and Required Characteristics 112 6 Implementation of the Developed Concepts 115 6.1 Implementation of Sensor Bus and Semantic Mediators 115 6.2 Implementation of the SID Interpreter 120 7 Application and Evaluation of the Developed Methods 123 7.1 Applying the Developed Methods in a Combined Way 124 7.2 On-the-fly Integration of Geosensors to Facilitate Flood Monitoring 127 7.2.1 Publishing the G-WaLe Sensor Data 127 7.2.2 Tasking of the G-WaLe Sensor 130 7.3 Tool Supported Sensor Integration 135 7.3.1 User Study Setup 135 7.3.2 Analysis and Evaluation of the User Study 138 7.4 Semantically-enabled Sensor Plug & Play in the Oil Spill Scenario 141 7.5 Lessons Learned from the Application of the Approach 151 8 Conclusions 155 8.1 Discussion 155 8.1.1 On-the-fly Integration of Sensors and the Sensor Web through the Sensor Bus 156 8.1.2 Closing the Interoperability Gap with Sensor Interface Descriptors 158 8.1.3 Completing the Vertical Integration with Supporting Tools 161 8.1.4 Semantic Mediation of Sensors and Services 162 8.2 Answers to Research Questions and Resulting Contributions 164 8.3 Recommendations for Future Work 168 8.3.1 Future Work on the Sensor Bus 168 8.3.2 Future Work on Sensor Interface Descriptors 169 8.3.3 Future Work on the SID Creator 170 8.3.4 Future Work on the Semantic Mediation Mechanism 170 A Example Sensor Interface Descriptor Instance 173 Bibliography 185