Thesis (MDistance Ed) -- University of South Australia, 1994

This dissertation was motivated by the exponential growth in bandwidth capacity of the Internet, coupled with the immense growth of broadband adoption by the public. This has led to the development of a wide variety of new online services. Chief amongst the emerging applications is the delivery of multimedia contents to the end users via the network on-demand. It is the “on-demand” aspect that has led to problems which, despite the advances in hardware technology and network capacity, have hampered wide scale adoption of multimedia delivery. The focus of this dissertation was to address these problems, namely: scalability, cost-effectiveness, and network quality of service for timely presentation of multimedia contents. We proposed an architecture, which we referred to as “Delayed-Multicast”, to address the scalability problem. The new architecture introduced buffers within the network to reduce demands on core network bandwidth and server load. A feasibility study of the architecture was conducted through the use of a prototype. It was found that such a system is within reach by demonstrating the prototype using cheap, common-of-the-shelf (COTS) components, and with help of freely available system software such Linux with real-time support. The introduction of buffers within the network led to the requirement of how to minimize buffer space. We developed an optimal algorithm for allocating buffer space in a single level caching layout (i.e. only one buffer in the transmission path from the server to the end user). For the case of multi-levels network caching, we thoroughly examined different optimization problems from an algorithmic perspective. These problems included how to minimize total system memory, and minimize the maximum memory used per node. We proved that determining the optimal buffer allocation in many of these iv v cases is an NP-complete problem. Consequently, we developed heuristics to handle multi-level caching and showed through simulations that the heuristics greatly help in minimizing buffer space and network bandwidth requirement. An important aspect of the heuristics was how to handle the case when the arrival times of client requests were not known a priori. For these “online” problems we also proposed heuristics that can significantly reduce overall system resource requirements. If the cost of buffer space was also taken into account along with the cost of network bandwidth, a different optimization problem was how to minimize the total system cost. Here, we also proposed heuristics, which in simulations show that the total system cost can be significantly reduced. Besides the problems associated with resource allocation, in terms of buffer space and bandwidth, we also examined the problem of how to provision the necessary network quality of service on-demand. Most current networks rely on best-effort delivery which is ill suited for the delivery of multimedia traffic. We proposed a solution which relied on the use of a programmable network plane, that is present in many current routers, to dynamically alter the priority of flows within the network in real-time. We also demonstrated the effectiveness of the flow prioritization on an actual Nortel router. Finally, we examined the problem of how to admit and achieve fair bandwidth allocation for the end-users within a Differentiated Service (DiffServ) network. Diff- Serv is an IETF standard that aims to provide a “better than best-effort” network in a scalable manner, and is used widely, especially within the same autonomous domain for prioritization different classes of traffic. However, there are open problems on how to provide fair bandwidth allocation amongst competing flows. We proposed an edge-aware resource discovery loop, which as the name suggests, sent packets to gather information about the internal states of the core network. With this information, we proposed a price-based admission control algorithm for use within the DiffServ network that would allow fair admission, effective congestion control, and fair bandwidth allocation amongst different traffic flows.

175 leaves : ill. (part col.) tables, graphs ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical Engineering, 1978

Innovative improvements in the area of Human-Computer Interaction and User Interfaces have en-abled intuitive and effective applications for a variety of problems. On the other hand, there has also been the realization that several real-world optimization problems still cannot be totally auto-mated. Very often, user interaction is necessary for refining the optimization problem, managing the computational resources available, or validating or adjusting a computer-generated solution. This thesis investigates how humans can help optimization methods to solve such difficult prob-lems. It presents an interactive framework where users play a dynamic and important role by pro-viding hints. Hints are actions that help to insert domain knowledge, to escape from local minima, to reduce the space of solutions to be explored, or to avoid ambiguity when there is more than one optimal solution. Examples of user hints are adjustments of constraints and of an objective function, focusing automatic methods on a subproblem of higher importance, and manual changes of an ex-isting solution. User hints are given in an intuitive way through a graphical interface. Visualization tools are also included in order to inform about the state of the optimization process. We apply the User Hints framework to three combinatorial optimization problems: Graph Clus-tering, Graph Drawing and Map Labeling. Prototype systems are presented and evaluated for each problem. The results of the study indicate that optimization processes can benefit from human interaction. The main goal of this thesis is to list cases where human interaction is helpful, and provide an ar-chitecture for supporting interactive optimization. Our contributions include the general User Hints framework and particular implementations of it for each optimization problem. We also present a general process, with guidelines, for applying our framework to other optimization problems.

Master of Visual Arts / Digital/video games1 have entertained for 40 years and are a medium with the ability to reach a vast audience. In an article published in the Sydney Morning Herald, Charles Purcell reports that; “Globally, Halo 2 has sold more than 7 million copies. Both in the US and Australia it broke the film box-office record for the most earnings in the first 24 hours of release. The worldwide Halo 2 community on X-box Live has about 400,000 players… at the World Cyber Games in Seoul. Last year, gold medallist Matthew Leto won $US20,000 ($AUS27,0000) after his second consecutive Halo title.” 2. Game consoles have become a part of many lounge rooms just as the television did before them. Games are even commonplace in many coat pockets and carrying bags. This dissertation is concerned with the medium of digital/video games in relation to its effect on Game Art. It is also concerned with the concept of my studio work that deals with “evil” and the “uncanny” which are discussed in chapter four. My research looks at games and how they have developed and the relationship to contemporary art. A history of this development is explored in chapter two. My research will help me in developing an interactive piece. Throughout my current research the thoughts of author of The Second Self: Computers and the Human Spirit Sherry Turkle resonate: “…not what will the computer be like in the future, but instead, what will we be like? What kind of people are we becoming?” 3 It is interesting to consider the video/digital games as experiments of who we are or who we would like to be, little fantasies of empowerment. In a game we are able to live out our frustrations or fantasies in a closed and predictable experience.

Thesis (M.F.A.)--Rochester Institute of Technology, 2007. / Typescript. Accompanying CD-ROM contains the Online Cake Instructor module. Includes bibliographical references (leaves 44-45).

Thesis (M.S.)--University of North Carolina at Greensboro, 2007. / Title from PDF t.p. (viewed Feb. 28, 2008). Directed by Patrick Lee Lucas; submitted to the School of Human Environmental Sciences. Includes bibliographical references (p. 149-152).

Thesis (Ed. D.)--Illinois State University, 2006. / Title from title page screen, viewed on February 4, 2008. Dissertation Committee: Dent M. Rhodes (chair), Ellen A. Spycher, Chandra Sommers, Kenneth F. Jerich. Includes bibliographical references (leaves 109-117) and abstract. Also available in print.

Thesis (M.S.)--Rochester Institute of Technology, 1989. / Includes bibliographical references (leaves 78-79).

Thesis (M.F.A.)--College of Fine Arts, University of new South Wales, 1999. / Bibliography: p. 113-115. Also available online.