A Semantics-Based Approach to Machine Perception
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Wright State University CORE Scholar Browse all Theses and Dissertations Theses and Dissertations 2013 A Semantics-Based Approach to Machine Perception Cory Andrew Henson Wright State University Follow this and additional works at: https://corescholar.libraries.wright.edu/etd_all Part of the Computer Engineering Commons, and the Computer Sciences Commons Repository Citation Henson, Cory Andrew, "A Semantics-Based Approach to Machine Perception" (2013). Browse all Theses and Dissertations. 1154. https://corescholar.libraries.wright.edu/etd_all/1154 This Dissertation is brought to you for free and open access by the Theses and Dissertations at CORE Scholar. It has been accepted for inclusion in Browse all Theses and Dissertations by an authorized administrator of CORE Scholar. For more information, please contact [email protected]. A Semantics-based Approach to Machine Perception A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy By CORY ANDREW HENSON B.A., University of Georgia, 2005 2013 Wright State University COPYRIGHT BY Cory Henson 2013 WRIGHT STATE UNIVERSITY GRADUATE SCHOOL December 14, 2013 I HEREBY RECOMMEND THAT THE DISSERTATION PREPARED UNDER MY SUPERVISION BY Cory Andrew Henson ENTITLED A Semantics-based Approach to Machine Perception BE ACCEPTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF Doctor of Philosophy. ______________________________ Amit P. Sheth, Ph.D. Dissertation Director ______________________________ Arthur A. Goshtasby, Ph.D. Director, Computer Science Ph.D. Program ______________________________ R. William Ayres, Ph.D. Interim Dean, Graduate School Committee on Final Examination ______________________________ Amit P. Sheth, Ph.D. ______________________________ Krishnaprasad Thirunarayan, Ph.D. ______________________________ Payam Barnaghi, Ph.D. ______________________________ Satya S. Sahoo, Ph.D. ______________________________ John Gallagher, Ph.D. Abstract Henson, Cory Andrew. Ph.D., Computer Science and Engineering Ph.D. Program, Wright State University, 2013. A Semantics-based Approach to Machine Perception. Machine perception can be formalized using semantic web technologies in order to derive abstractions from sensor data using background knowledge on the Web, and efficiently executed on resource-constrained devices. Advances in sensing technology hold the promise to revolutionize our ability to observe and understand the world around us. Yet the gap between observation and understanding is vast. As sensors are becoming more advanced and cost-effective, the result is an avalanche of data of high volume, velocity, and of varied type, leading to the problem of too much data and not enough knowledge (i.e., insights leading to actions). Current estimates predict over 50 billion sensors connected to the Web by 2020. 1 While the challenge of data deluge is formidable, a resolution has profound implications. The ability to translate low-level data into high-level abstractions closer to human understanding and decision-making has the potential to disrupt data-driven interdisciplinary sciences, such as environmental science, healthcare, and bioinformatics, as well as enable other emerging technologies, such as the Internet of Things. The ability to make sense of sensory input is called perception; and while people are able to perceive their environment almost instantaneously, and seemingly without effort, machines 1 http://share.cisco.com/internet-of-things.html continue to struggle with the task. Machine perception is a hard problem in computer science, with many fundamental issues that are yet to be adequately addressed, including: (a) annotation of sensor data, (b) interpretation of sensor data, and (c) efficient implementation and execution. This dissertation presents a semantics-based machine perception framework to address these issues. The tangible primary contributions created to support the thesis of this dissertation include the development of a Semantic Sensor Observation Service (SemSOS) for accessing and querying sensor data on the Web, an ontology of perception (Intellego) that provides a formal semantics of machine perception and reasoning framework for the interpretation of sensor data, and efficient algorithms for the machine perception inference tasks to enable interpretation of sensor data on resource-constrained devices, such as smart phones. Each of these contributions has been prototyped, evaluated, and applied towards solving real-world problems in multiple domains including weather and healthcare. Table of Contents 1. Introduction ....................................................................................................................1 1.1. Contributions ........................................................................................................................................ 2 1.2. Chapter Overview ................................................................................................................................ 4 2. Semantic Sensor Web ....................................................................................................7 2.1. Background .......................................................................................................................................... 8 2.1.1. Sensor Web Enablement .............................................................................................................. 8 2.1.2. SWE Sensor Observation Service ............................................................................................... 9 2.1.3. Semantic Web ........................................................................................................................... 11 2.2. Semantic Sensor Observation Service ............................................................................................... 13 2.2.1. Observations and Measurements Ontology ............................................................................... 14 2.2.2. Spatial, Temporal, and Thematic Ontologies ............................................................................ 18 2.2.3. Semantic Annotation of SWE .................................................................................................... 19 2.2.4. Rule Based Reasoning ............................................................................................................... 20 2.2.5. SemSOS Implementation .......................................................................................................... 24 2.2.5.1. 52North SOS ..................................................................................................................... 25 2.2.5.2. SemSOS Extensions to 52North ........................................................................................ 26 2.2.5.3. Example SemSOS Query Processing ................................................................................ 27 2.3. Linked Sensor Data ............................................................................................................................ 30 2.4. Semantic Sensor Network Ontology ................................................................................................. 35 2.5. Concluding Remarks .......................................................................................................................... 38 3. Semantic Perception ...................................................................................................40 3.1. Cognitive Models of Perception ....................................................................................................... 42 3.2. Ontology of Perception – Set Theory ............................................................................................... 45 3.2.1. Semantics of Perception: Concepts and Relations .................................................................... 47 3.2.2. Semantics of Perception: Processes .......................................................................................... 49 3.2.2.1. Observation Process ........................................................................................................... 50 3.2.2.2. Perception Process .............................................................................................................. 51 3.2.2.3. Perception Cycle ................................................................................................................. 52 3.2.3. Evaluation .................................................................................................................................. 58 3.2.3.1. Focus Evaluation ................................................................................................................ 58 3.2.3.1.1. Background Knowledge for Focus Evaluation ......................................................... 60 3.2.3.1.2. Implementation ......................................................................................................... 61 3.2.3.1.3. Experiment Setup ...................................................................................................... 64 3.2.3.1.4. Experiment 1: No Focus (brute force approach) ....................................................... 65 3.2.3.1.5. Experiment 2: With Focus ........................................................................................ 67 3.2.3.1.6. Experiment 3: With Optimized Focus ...................................................................... 70 3.2.3.2. Expressivity