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A Collaborative Ocean Visualization Environment The Design of COVE: a Collaborative Ocean Visualization Environment Keith Grochow A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy University of Washington 2011 Program Authorized to Offer Degree: Computer Science & Engineering University of Washington Graduate School This is to certify that I have examined this copy of a doctoral dissertation by Keith Grochow and have found that it is complete and satisfactory in all respects, and that any and all revisions required by the final examining committee have been made. Chair of the Supervisory Committee: _____________________________________________________ Edward Lazowska Reading Committee: ______________________________________________________ Edward Lazowska ______________________________________________________ James Fogarty ______________________________________________________ John Delaney Date: ____________________________________________ In presenting this dissertation in partial fulfillment of the requirements for the doctoral degree at the University of Washington, I agree that the Library shall make its copies freely available for inspection. I further agree that extensive copying of the dissertation is allowable only for scholarly purposes, consistent with “fair use” as prescribed in the U.S. Copyright Law. Requests for copying or reproduction of this dissertation may be referred to ProQuest Information and Learning, 300 North Zeeb Road, Ann Arbor, MI 48106-1346, 1-800-521- 0600, to whom the author has granted “the right to reproduce and sell (a) copies of the manuscript in microform and/or (b) printed copies of the manuscript made from microform.” Signature__________________________________ Date_____________________________________ University of Washington Abstract The Design of COVE: a Collaborative Ocean Visualization Environment Keith Grochow Chair of the Supervisory Committee: Professor Edward Lazowska Computer Science & Engineering Ocean observatories, exemplified by the NSF Ocean Observatories Initiative (OOI), aim to transform oceanography from an expeditionary to an observation-based science. To do so, new cyberinfrastructure environments are helping scientists from disparate fields jointly conduct experiments, manage large collections of instruments, and explore extensive archives of observed and simulated data. However, such environments often focus on systems, networking, and databases and ignore the critical importance of rich 3D interactive visualization, asset management, and collaboration needed to effectively communicate across interdisciplinary science teams. This dissertation presents the design, implementation, and evaluation of an interactive ocean data exploration system designed to satisfy the unmet needs of the multidisciplinary ocean observatory community. After surveying existing literature and performing a multi- month contextual design study that included input from scientists at multiple institutions, I propose a set of guidelines for the system’s user interface and design. Motivated by these guidelines and informed by close collaboration with multidisciplinary ocean scientists, I then present the Collaborative Ocean Visualization Environment (COVE), a new data exploration system that combines the ease of use of geobrowsers, such as Google Earth, with the data exploration and visualization capabilities of sophisticated science systems. To validate COVE’s design, I evaluated its capabilities in three ways. (1) User studies showed that it works efficiently for expert and novice data explorers as well as visualization producers and consumers. (2) Multiple real-world science deployments, both on land and at i sea, saw it replace existing systems for observatory design, provide faster and more engaging planning and data analysis for science teams, and enhance mission preparation and navigation for the ALVIN research submarine. (3) An analysis of COVE over local, server and cloud-based resources indicated that its flexible work partitioning architecture is essential for real-world observatory data analysis and visualization tasks. ii TABLE OF CONTENTS Page List of Figures ..................................................................................................................... iii List of Tables ..................................................................................................................... vii Glossary ......................................................................................................................... viii Chapter 1 Introduction .........................................................................................................1 1.1 Thesis Contributions ............................................................................................. 4 1.2 Outline of the Thesis ............................................................................................. 5 1.3 Observing the Ocean ............................................................................................. 6 1.4 Ocean Observatory Challenges ........................................................................... 11 Chapter 2 Related Work and Gap Analysis .......................................................................16 2.1 Data Types .......................................................................................................... 16 2.2 Data Exploration Tasks ....................................................................................... 18 2.3 Data Exploration and Visualization Systems ...................................................... 28 2.4 Gap Analysis ....................................................................................................... 33 2.5 Conclusion .......................................................................................................... 38 Chapter 3 Contextual Design Study ...................................................................................40 3.1 Methodology ....................................................................................................... 40 3.2 Key Themes ........................................................................................................ 42 3.3 Design Guidelines ............................................................................................... 50 3.4 Conclusion .......................................................................................................... 52 Chapter 4 COVE ................................................................................................................53 4.1 Visualizing and Exploring Data .......................................................................... 56 4.2 Instrument Layout and Management .................................................................. 59 4.3 Collaboration and Communication ..................................................................... 62 i 4.4 Architecture and Implementation ....................................................................... 65 4.5 Conclusion .......................................................................................................... 67 Chapter 5 Usability Evaluation ..........................................................................................68 5.1 Ocean Data Experts and Novices: Study 1 ......................................................... 69 5.2 Visualization Producers and Consumers: Study 2 ............................................. 77 5.3 Conclusion .......................................................................................................... 82 Chapter 6 COVE in the Field .............................................................................................84 6.1 Observatory Design ............................................................................................ 84 6.2 Mapping RSN Sites............................................................................................. 88 6.3 Exploring Geothermal Vents with ALVIN ......................................................... 93 6.4 Conclusion .......................................................................................................... 98 Chapter 7 Scaling to the Cloud ........................................................................................100 7.1 Architecture Overview ...................................................................................... 101 7.2 Experiment Design............................................................................................ 106 7.3 Experimental Analysis ...................................................................................... 113 7.4 Results ............................................................................................................... 115 7.5 Conclusion ........................................................................................................ 119 Chapter 8 Conclusion and Future Work ..........................................................................120 8.1 Contributions..................................................................................................... 120 8.2 Future Work ...................................................................................................... 122 8.3 Closing Remarks ............................................................................................... 125 Bibliography ......................................................................................................................126 Appendix
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