Symmetric Edit Lenses: A New Foundation for Bidirectional Languages

Lenses are bidirectional transformations between pairs of connected structures capable of translating an edit on one structure into an edit on the other. Most of the extensive existing work on lenses has focused on the special case of asymmetric lenses, where one structures is taken as primary and the other is thought of as a projection or view. Some symmetric variants exist, where each structure contains information not present in the other, but these all lack the basic operation of composition. Additionally, existing accounts do not represent edits carefully, making incremental operation difficult or producing unsatisfactory synchronization candidates. We present a new symmetric formulation which works with descriptions of changes to structures, rather than with the structures themselves. We construct a semantic space of edit lenses between “editable structures”—monoids of edits with a partial monoid action for applying edits—with natural laws governing their behavior. We present generalizations of a number of known constructions on asymmetric lenses and settle some longstanding questions about their properties—in particular, we prove the existence of (symmetric monoidal) tensor products and sums and the non-existence of full categorical products and sums in a category of lenses. Universal algebra shows how to build iterator lenses for structured data such as lists and trees, yielding lenses for operations like mapping, filtering, and concatenation from first principles. More generally, we provide mapping combinators based on the theory of containers. Finally, we present a prototype implementation of the core theory and take a first step in addressing the challenge of translating between user gestures and the internal representation of edits

4. TITLE AND SUBTITLE: Title (Mix case letters) Efficient Nearly Orthogonal and Space-Filling Experimental for High-Dimensional Complex Models

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THE INFLUENCE OF DEVELOPING A WEB-BASED COURSE ON UNIVERSITY PROFESSOR CLASSROOM INSTRUCTIONAL TECHNIQUES AS MEASURED BY THE MTQ

Of course, I must first thank Dr. Messner for hours of reading, re-reading, encouragement and support. His advice and insight have been invaluable. I would also like to thank members of my committee for all of their assistance throughout this process. Looking back further, this dissertation and my path of learning would never have been possible without my parents exemplifying a love of lifelong learning themselves. I thank them for encouraging me to question and think. I also am in deep gratitude to Carolyn Phelps for providing me room (and board) on nights like these, when I am away from home, writing. It is impossible to understate how she, Gary and my parents have positively affected my life. I often reflect on the first July that I spent in Columbia. As the time to leave home approached, two of our three vehicles became inoperable. In order to be punctual, I set out in the only working vehicle, leaving Kathryn, my wife, home to pick up the pieces without transportation. Many times throughout this doctoral experience, it seems that I have rushed off in a flash leaving Kathryn to pick up the pieces of our lives. When multiple priorities competed for my time and energy, she always was the one that gave. I could never have endured without her unwavering love and support. My daughters, Darell and Phelps, have also given up a lot without even knowing it sometimes. Their pleas of “When are you coming home, Dad ” were always heard, and I thank them for their patience and tolerance. It is to Kathryn, Darell and Phelps that I dedicate this final product. i

A Software Architecture for the Construction and Management of Real-Time Virtual Worlds

As military budgets shrink, the Department of Defense (DoD) is turning to virtual worlds (VW) to solve problems and address issues that were previously solved by prototype or field exercises. However, there is a critical void of experience in the community on how to build VW systems. The Naval Postgraduate School\u92s Network Vehicle Simulator (NPSNET) was designed and built to address this need. NPSNET is a populated, networked, interactive, flexible, three dimensional (3D) virtual world system. This dissertation covers the construction and management of the VW in NPSNET. The system, which uses both standard and non-standard network message formats, is fully networked allowing multiple users to interact simultaneously in the VW. Commercial off the shelf (COTS), Silicon Graphics Incorporated (SGI) workstations, hardware was used exclusively in NPSNET to ensure the usefulness and the portability of the system to many DoD commands. The core software architecture presented here is suitable for any VW

Dedicated to my dad

The undersigned, appointed by the Dean of the Graduate School, Have examined the dissertation entitled