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Equation of State and Heat Content of Uranium

Description: Report issued by the APDA over studies conducted on the state of uranium at different temperature and pressure. Calculations are presented for the differing pressures of uranium. This report includes tables.
Date: February 20, 1957
Creator: Brout, Robert H.
Partner: UNT Libraries Government Documents Department

Random growth of interfaces: Statistical analysis of single columns and detection of critical events.

Description: The dynamics of growth and formation of surfaces and interfaces is becoming very important for the understanding of the origin and the behavior of a wide range of natural and industrial dynamical processes. The first part of the paper is focused on the interesting field of the random growth of surfaces and interfaces, which finds application in physics, geology, biology, economics, and engineering among others. In this part it is studied the random growth of surfaces from within the perspective of a single column, namely, the fluctuation of the column height around the mean value, which is depicted as being subordinated to a standard fluctuation-dissipation process with friction g. It is argued that the main properties of Kardar-Parisi-Zhang theory are derived by identifying the distribution of return times to y(0) = 0, which is a truncated inverse power law, with the distribution of subordination times. The agreement of the theoretical prediction with the numerical treatment of the model of ballistic deposition is remarkably good, in spite of the finite size effects affecting this model. The second part of the paper deals with the efficiency of the diffusion entropy analysis (DEA) when applied to the studies of stromatolites. In this case it is shown that this tool can be confidently used for the detection of complexity. The connection between the two studies is established by the use of the DEA itself. In fact, in both analyses, that is, the random growth of interfaces and the study of stromatolites, the method of diffusion entropy is able to detect the real scaling of the system, namely, the scaling of the process is determined by genuinely random events, also called critical events.
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Date: August 2004
Creator: Failla, Roberto
Partner: UNT Libraries

Lyapunov Exponents, Entropy and Dimension

Description: We consider diffeomorphisms of a compact Riemann Surface. A development of Oseledec's Multiplicative Ergodic Theorem is given, along with a development of measure theoretic entropy and dimension. The main result, due to L.S. Young, is that for certain diffeomorphisms of a surface, there is a beautiful relationship between these three concepts; namely that the entropy equals dimension times expansion.
Date: August 2004
Creator: Williams, Jeremy M.
Partner: UNT Libraries

The Nonadditive Generalization of Klimontovich's S-Theorem for Open Systems and Boltzmann's Orthodes

Description: We show that the nonadditive open systems can be studied in a consistent manner by using a generalized version of S-theorem. This new generalized S-theorem can further be considered as an indication of self-organization in nonadditive open systems as prescribed by Haken. The nonadditive S-theorem is then illustrated by using the modified Van der Pol oscillator. Finally, Tsallis entropy as an equilibrium entropy is studied by using Boltzmann's method of orthodes. This part of dissertation shows that Tsallis ensemble is on equal footing with the microcanonical, canonical and grand canonical ensembles. However, the associated entropy turns out to be Renyi entropy.
Date: August 2008
Creator: Bagci, Gokhan Baris
Partner: UNT Libraries

Widening the lens: An interdisciplinary approach to examining the effect of exposure therapy on public speaking state anxiety.

Description: This study used an interdisciplinary approach to examine an intervention for reducing public speaking state anxiety. A quasi-experiment was conducted to determine if a multiple-exposure treatment technique (TRIPLESPEAK) would help to attenuate public speaking anxiety. The treatment group reported experiencing significantly less state anxiety during their post-test presentation than did the control group. This lead to the conclusion that exposure therapy can be used to help students enrolled in basic communication classes begin to overcome their fear of speaking in front of an audience. Follow-up analysis of the treatment group's reported anxiety levels during all five presentations (pre-test, Treatment Presentation 1, Treatment Presentation 2, Treatment Presentation 3, and post-test) revealed an increase in anxiety from the last treatment presentation to the post-test presentation. In order to explore this issue, Shannon's entropy was utilized to calculate the amount of information in each speaking environment. Anderson's functional ontology construction approach served as a model to explain the role of the environment in shaping speakers' current and future behaviors and reports of anxiety. The exploratory analysis revealed a functional relationship between information and anxiety. In addition, a qualitative study was conducted to determine which environmental stimuli speakers perceived contributed to their anxiety levels. Students reported experiencing anxiety based on four categories, which included speaker concerns, audience characteristics, contextual factors and assignment criteria. Students' reports of anxiety were dependent upon their previous speaking experiences, and students suggested differences existed between the traditional presentations and the treatment presentations. Pedagogical and theoretical implications are discussed.
Date: August 2007
Creator: Finn, Amber N.
Partner: UNT Libraries

A multi-dimensional entropy model of jazz improvisation for music information retrieval.

Description: Jazz improvisation provides a case context for examining information in music; entropy provides a means for representing music for retrieval. Entropy measures are shown to distinguish between different improvisations on the same theme, thus demonstrating their potential for representing jazz information for analysis and retrieval. The calculated entropy measures are calibrated against human representation by means of a case study of an advanced jazz improvisation course, in which synonyms for "entropy" are frequently used by the instructor. The data sets are examined for insights in music information retrieval, music information behavior, and music representation.
Date: December 2005
Creator: Simon, Scott J.
Partner: UNT Libraries

Framework to Evaluate Entropy Based Data Fusion Methods in Supply Chain Management

Description: This dissertation explores data fusion methodology to deduce an overall inference from the data gathered from multiple heterogeneous sources. Typically, if there existed a data source in which the data were reliable and unbiased, then data fusion would not be necessary. Data fusion methodology combines data form multiple diverse sources so that the desired information - such as the population mean - is improved despite redundancies, inaccuracies, biases, and inflated variability in the data. Examples of data fusion include estimating average demand from similar sources, and integrating fatality counts from different media sources after a catastrophe. The approach in this study combines "inputs" from distinct sources so that the information is "fused." Another way of describing this process is "data integration." Important assumptions are 1. Several sources provide "inputs" for information used to estimate parameters of a probability distribution. 2. Since distributions for the data from the sources are heterogeneous, some sources are less reliable. 3. Distortions, bias, censorship, and systematic errors may be more prominent in data from certain sources. 4. The sample size of sources data, number of "inputs," may be very small. Examples of information from multiple sources are abundant: traffic information from sensors at intersections, multiple economic indicators from various sources, demand data for product using similar retail stores as sources, polling data from various sources, and disaster count of fatalities from different media sources after a catastrophic event. This dissertation seeks to address a gap in the operations literature by addressing three research questions regarding entropy base data fusion (EBDF) approaches to estimation. Three separate, but unifying, essays address the research questions for this dissertation. Essay 1 provides an overview of supporting literature for the research questions. A numerical analysis of airline maximum wait time data illustrates the underlying issues involved in EBDF methods. This ...
Date: December 2016
Creator: Tran, Huong Thi
Partner: UNT Libraries