Thesis (M.S. in Modeling, Virtual Environments, and Simulation)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Wolfgang Baer, David W. Laflam. Includes bibliographical references (p. 61-63). Also available online.

Thesis (Ph. D.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 167-179).

Thesis (M.S. in Modeling, Virtual Environments and Simulation)--Naval Postgraduate School, March 2003. / Thesis advisor(s): Rudolph P. Darken, Joseph A. Sullivan. Includes bibliographical references (p. 137-140). Also available online.

Thesis (Ph. D.)--Ohio State University, 2003. / Title from first page of PDF file. Document formatted into pages; contains xiii, 102 p.: ill. (some col.). Includes abstract and vita. Advisor: Roger A. Crawfis, Dept. of Computer and Information Science. Includes bibliographical references (p. 98-102).

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 83-87).

There has been a rapid growth in the vehicle industry market, companies are expected to provide comfortable and safer products, improving with every new model. Hence, the interest on developing Digital Human Modelling (DHM) tools that are focused on their needs. The aim of this project is to suggest a standard seating posture that could be used with ergonomic software like IMMA, to address the research an initial literature study was performed to understand existing methods used in the industry and previous posture studies. In order to visualize the extent of the topic, it was required to acquire information from the vehicle industries and make an investigation on preferred postures by real drivers. Comparisons are made between the different categories of observed vehicles, and literature found for ideal postures. The results were also used to implement suggestions for the ergonomic IMMA software development / Virtual Driver Research

Computational methods have become an integral part of drug development and can help bring new and better drugs to the market faster. The process of predicting the biological activity of large compound collections is known as virtual screening, and has been instrumental in the development of several drugs today in the market. Computational methods can also be used to elucidate the energies associated with chemical reactivity and predict how to improve a synthetic protocol. These two applications of computational medicinal chemistry is the focus of this thesis. In the first part of this work, quantum mechanics has been used to probe the energy surface of palladium(II)-catalyzed decarboxylative reactions in order to gain a better understating of these systems (paper I-III). These studies have mapped the reaction pathways and been able to make accurate predictions that were verified experimentally. The other focus of this work has been to develop virtual screening methodology. Our first study in the area (paper IV) investigated if the results from several virtual screening methods could be combined using data fusion techniques in order to get a more consistent result and better performance. The study showed that the results obtained from data fusion were more consistent than the results from any single method. The data fusion methods also for several target had a better performance than any of the included single methods. Next, we developed a dataset suitable for evaluating the performance of virtual screening methods when applied to large compound collection as a replacement or complement for high throughput screening (paper V). This is the first benchmark dataset of its kind. Finally, a method for using computationally derived reaction coordinates as basis for virtual screening was developed. The aim was to find inhibitors that resemble key steps in the mechanism (paper VI). This initial proof of concept study managed to locate several known and one previously not reported reaction mimetics against insulin regulated amino peptidase.

Globalization, global competitive market forces and technological progress have made Geographically Distributed Development (GDD) possible and a necessity for most companies in the world. The software industry has consistently been at the forefront of exploring and implementing this business model. This thesis studies the key drivers of GDD, identifies the major challenges which global virtual teams face and existing frameworks for successful global virtual teams. A case study is used to validate the challenges and concerns of managing a global virtual team and a framework is proposed to help overcome the challenges and enable successful global software development. / text

As articulated by J. K. Wright (1947), "terrae incognitae," or unknown lands, capture the imagination and inspire an excitement to explore and learn, but with a reduction in travel times and subsequent expansions of potential travel range, along with growth in media and the development of the video game industry, for many, terrae incognitae has shifted from places on Earth to the intangible environments of interactive media. While the virtual environments of video games can be fantastic, they are also designed and created by human beings to exist entirely in relation to the game player, who is an adventurer, explorer, settler, civilizer, or conqueror. Using qualitative research methods, this dissertation analyzes the geographies online video gaming in relation to an original framework based on the mutually constitutive concepts of representation, exploration, and geographic narrative, as well as the intersecting roles of myth, fantasy, and the virtual in shaping narratively structured imaginative environments. With specific chapters examining themes of interaction between human and software, gender and sexuality, exploration, narrative, cooperation, and creativity, this dissertation proposes that video games can be best understood as both collaborative representations and virtual environments. / text

Given the popularity of Java, extending the standard Java virtual machine (JVM) to become cluster-aware effectively brings the vision of transparent horizontal scaling of applications to fruition. With a set of cluster-wide JVMs orchestrated as a virtually single system, thread-level parallelism in Java is no longer confined to one multiprocessor. An unmodified multithreaded Java application running on such a Distributed JVM (DJVM) can scale out transparently, tapping into the vast computing power of the cluster. While this notion creates an easy-to-use and powerful parallel programming paradigm, research on DJVMs has remained largely at the proof-of-concept stage where successes were proven using trivial scientific computing workloads only. Real-life Java applications with commercial server workloads have not been well-studied on DJVMs. Their natures including complex and sometimes huge object graphs, irregular access patterns and frequent synchronizations are key scalability hurdles. To design a scalable DJVM for real-life applications, we identify three major unsolved issues calling for a top-to-bottom overhaul of traditional systems. First, we need a more time- and space-efficient cache coherence protocol to support fine-grained object sharing over the distributed shared heap. The recent prevalence of concurrent data structures with heavy use of volatile fields has added complications to the matter. Second, previous generations of DJVMs lack true support for memory-intensive applications. While the network-wide aggregated physical memory can be huge, mutual sharing of huge object graphs like Java collections may cause nodes to eventually run out of local heap space because the cached copies of remote objects, linked by active references, can’t be arbitrarily discarded. Third, thread affinity, which determines the overall communication cost, is vital to the DJVM performance. Data access locality can be improved by collocating highly-correlated threads, via dynamic thread migration. Tracking inter-thread correlations trades profiling costs for reduced object misses. Unfortunately, profiling techniques like active correlation tracking used in page-based DSMs would entail prohibitively high overheads and low accuracy when ported to fine-grained object-based DJVMs. This dissertation presents technical contributions towards all these problems. We use a dual-protocol approach to address the first problem. Synchronized (lock-based) and volatile accesses are handled by a home-based lazy release consistency (HLRC) protocol and a sequential consistency (SC) protocol respectively. The two protocols’ metadata are maintained in a conflict-free, memory-efficient manner. With further techniques like hierarchical passing of lock ownerships, the overall communication overheads of fine-grained distributed object sharing are pruned to a minimal level. For the second problem, we develop a novel uncaching mechanism to safely break a huge active object graph. When a JVM instance runs low on free memory, it initiates an uncaching policy, which eagerly assigns nulls to selected reference fields, thus detaching some older or less useful cached objects from the root set for reclamation. Careful orchestration is made between uncaching, local garbage collection and the coherence protocol to avoid possible data races. Lastly, we devise lightweight sampling-based profiling methods to derive inter-thread correlations, and a profile-guided thread migration policy to boost the system performance. Extensive experiments have demonstrated the effectiveness of all our solutions. / published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy