Thesis (B.Sc)--University of Hong Kong, 2005. / Includes bibliographical references (p. 176-179)

Thesis (Ph. D.)--University of Hong Kong, 2007. / Title proper from title frame. Also available in printed format.

This thesis describes in vitro and in vivo evaluation of a gastric retention formulation (GRF) developed at Oregon State University. The formulation was prepared from xanthan gum and locust bean gum as gelling agents and other formulation ingredients were added, then it was originally vacuum oven dried. The effect of freeze drying on GRF was studied in this research. Freeze dried GRF were evaluated for dissolution and drug release properties using hydrochlorothiazide as a model drug. The effect of storage of GRF inside hard gelatin capsules on rate of swelling of the capsule shell and release of GRF was also studied. Storage for up to 12 months had no effect on capsule shell swelling and release of GRF. Gastric residence time, pharmacokinetics and bioavailability of hydrochlorothiazide, a drug that has an absorption window limited to the upper small intestine, from two different sizes of gastric retention formulations (GRF) were evaluated in 12 healthy volunteers in both fed and fasted states, and compared to immediate release tablets. Extent of bioavailability of drug from the larger formulation in this study was comparable to IR tablets in both fed and fasted states. Deconvolved input functions data suggest that the GRF stayed in the stomach providing sustained drug input for 12-28 hours. Initial blood pressure lowering and side effects of hydrochlorothiazide from a gastric retention formulation were evaluated and compared to immediate release tablets in 10 subjects with stage I hypertension. Gastric retention formulations produced an average reduction in systolic blood pressure 3 mm Hg lower than IR tablets regardless of sequence of administration. GRF also produced less blood pressure fluctuation in most subjects than IR tablets. Most subjects reported fewer and less severe side effects with GRF than IR tablets. / Graduation date: 2004

Graduation date: 1998

This thesis examines the problem of an autonomous agent learning a causal world model of its environment. Previous approaches to learning causal world models have concentrated on environments that are too "easy" (deterministic finite state machines) or too "hard" (containing much hidden state). We describe a new domain --- environments with manifest causal structure --- for learning. In such environments the agent has an abundance of perceptions of its environment. Specifically, it perceives almost all the relevant information it needs to understand the environment. Many environments of interest have manifest causal structure and we show that an agent can learn the manifest aspects of these environments quickly using straightforward learning techniques. We present a new algorithm to learn a rule-based causal world model from observations in the environment. The learning algorithm includes (1) a low level rule-learning algorithm that converges on a good set of specific rules, (2) a concept learning algorithm that learns concepts by finding completely correlated perceptions, and (3) an algorithm that learns general rules. In addition this thesis examines the problem of finding a good expert from a sequence of experts. Each expert has an "error rate"; we wish to find an expert with a low error rate. However, each expert's error rate and the distribution of error rates are unknown. A new expert-finding algorithm is presented and an upper bound on the expected error rate of the expert is derived.

This thesis presents SodaBot, a general-purpose software agent user-environment and construction system. Its primary component is the basic software agent --- a computational framework for building agents which is essentially an agent operating system. We also present a new language for programming the basic software agent whose primitives are designed around human-level descriptions of agent activity. Via this programming language, users can easily implement a wide-range of typical software agent applications, e.g. personal on-line assistants and meeting scheduling agents. The SodaBot system has been implemented and tested, and its description comprises the bulk of this thesis.

Thesis (Ph. D.)--Ohio State University, 2006. / Full text release at OhioLINK's ETD Center delayed at author's request

Thesis (Ph.D.)--Baylor University, 2005. / Includes bibliographical references (p. 299-309).

Thesis (Ph.D.)--University of Delaware, 2006. / Principal faculty advisor: Eric W. Kaler, Dept. of Engineering. Includes bibliographical references.

Thesis (M.S.)--University of Florida, 2001. / Title from first page of PDF file. Document formatted into pages; contains ix, 65 p.; also contains graphics. Vita. Includes bibliographical references (p. 63-64).