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Compressibilities of gases

Description: Reproduction of thirteen graphs for computing compressibilities of various gases and for computing the volumes delivered from cylinders containing various gases.
Date: November 21, 1925
Creator: Pickering, Samuel Fisher
Partner: UNT Libraries Government Documents Department

A Classification of Regular Planar Graphs

Description: The purpose of this paper is the investigation and classification of regular planar graphs. The motive behind this investigation was a desire to better understand those properties which allow a graph to be represented in the plane in such a manner that no two edges cross except perhaps at vertices.
Date: December 1972
Creator: McCalla, Linda F.
Partner: UNT Libraries

Tensile and Impact Properties of Selected Materials From 20 to 300 ºK

Description: Report giving the tensile and impact properties of structural materials that were experimentally determined at temperatures from 20 to 300 ºK. Tensile properties of a few materials were also determined at 4 ºK. The properties experimentally determined were the yield strength, tensile strength, elongation, and reduction of area, the stress versus strain curve, and the impact energy. The test equipment and procedures are described. The individual data are presented in tables, and the average results are displayed in graphs.
Date: June 28, 1963
Creator: Warren, K. A. & Reed, R. P.
Partner: UNT Libraries Government Documents Department

Microwave Impedance Measurements and Standards

Description: Report presenting a survey and discussion of well-known microwave impedance measurement techniques. The discussion includes an introduction which emphasizes basic concepts and reflection coefficient-voltage standing-wave ratio relationships. Sources of error in the various measurement techniques are discussed and methods to reduce errors are presented. Methods using rotating loops and resonance lines are included and a brief discussion of microwave impedance standards is given.
Date: August 12, 1965
Creator: Beatty, Robert W.
Partner: UNT Libraries Government Documents Department

A Study of Lunar Surface Radio Communication

Description: Report discussing the problem of point-to-point radio communication on the moon. Equations and curves are presented to estimate power requirements in lunar communication systems. Consideration is given to ground wave attenuation over both layered and non-layered grounds, antenna ground losses in situations where ground screens are impractical, noise level estimates in the receiving system, and the effects on propagation of possible lunar ionospheres. An example of the calculation of required power for a particular communication system is given, and further studies are suggested.
Date: September 14, 1964
Creator: Vogler, L. E.
Partner: UNT Libraries Government Documents Department

Curves of Input Impedance Change Due to Ground for Dipole Antennas

Description: Report presenting graphs of the change in input impedance of electrically short dipole antennas in the presence of an isotropic and homogeneous ground which considers four types of antennas: horizontal and vertical, electric and magnetic dipoles. Curves of the change in both the input resistance and reactance are shown for a wide range of values of the frequency, antenna height above the ground, and electromagnetic ground constants.
Date: January 31, 1964
Creator: Vogler, L. E. & Noble, J. L.
Partner: UNT Libraries Government Documents Department

Colors of Signal Lights: Their Selection, Definition, Measurement, Production, and Use

Description: Report discussing the selection, specifications, and use of signal-light colors. It discusses the nature of the problem, and the mathematical representation, recognition, production, control, and use of such colors. The characteristics of different types of chromaticity boundaries and the purpose and effect of the requirement for similarity of chromaticity characteristics are given special consideration. The treatment is varied according to the intended use. The discussion of the control of colors and the section on the use of colors are nontechnical, whereas the section on the production of signal colors is designed for the colorimetrist who is faced with the problem of selecting limit filters or drafting a specification.
Date: April 3, 1967
Creator: Breckenridge, F. C.
Partner: UNT Libraries Government Documents Department

Radio Meteorology

Description: Report compiling the work done in radio meteorology over the past ten years at the National Bureau of Standards' Central Radio Propagation Laboratory (CRPL). There is an emphasis upon the effects of the lower atmosphere on the propagation of radio waves. The CRPL group has concentrated upon the refraction of radio waves as well as the refractive index structure of the lower atmosphere on both synoptic and climatic scales. Additional chapters on radio-meteorological parameters and the absorption of radio waves by the various constituents of the lower atmosphere.
Date: March 1, 1966
Creator: Bean, B. R. & Dutton, E. J.
Partner: UNT Libraries Government Documents Department

A Complete Mode Sum for LF, VLF, ELF Terrestrial Radio Wave Fields

Description: Report discussing the VLF, ELF propagation in the earth-ionosphere waveguide emphasizing the total field found by summing all modes which contribute appreciably. Solutions are given and calculations are made for a homogeneous isotropic ionosphere, a homogeneous ionosphere with a constant radial magnetic field imposed, and an ionosphere with a magnetic field of arbitrary dip angle.
Date: October 1, 1964
Creator: Johler, J. Ralph & Berry, Leslie A.
Partner: UNT Libraries Government Documents Department

Cycles and Cliques in Steinhaus Graphs

Description: In this dissertation several results in Steinhaus graphs are investigated. First under some further conditions imposed on the induced cycles in steinhaus graphs, the order of induced cycles in Steinhaus graphs is at most [(n+3)/2]. Next the results of maximum clique size in Steinhaus graphs are used to enumerate the Steinhaus graphs having maximal cliques. Finally the concept of jumbled graphs and Posa's Lemma are used to show that almost all Steinhaus graphs are Hamiltonian.
Date: December 1994
Creator: Lim, Daekeun
Partner: UNT Libraries

Analysis of Ambient Pollutant Concentrations and Meteorological Conditions Affecting EPA Class I and II Areas in Southeastern Louisiana, Volume 2: Appendices

Description: Appendices containing data that was collected as apart of a study on pollutants in Southeastern Louisiana. The four appendices include: [A] Gosier Island Hourly Data, [B] Breton Island (Chandeleur Islander) Hourly Data, [C] Pass-A-Loutre Hourly Data, and [D] Radiosonde Data.
Date: December 1996
Creator: Hsu, S. A.
Partner: UNT Libraries Government Documents Department

Topic Identification Using Wikipedia Graph Centrality

Description: This paper presents a method for automatic topic identification using a graph-centrality algorithm applied to an encyclopedic graph derived from Wikipedia. When tested on a data set with manually assigned topics, the system is found to significantly improve over a simpler baseline that does not make use of the external encyclopedic knowledge.
Date: May 2009
Creator: Coursey, Kino High & Mihalcea, Rada, 1974-
Partner: UNT College of Engineering

Matlab Implementation of a Tornado Forward Error Correction Code

Description: This research discusses how the design of a tornado forward error correcting channel code (FEC) sends digital data stream profiles to the receiver. The complete design was based on the Tornado channel code, binary phase shift keying (BPSK) modulation on a Gaussian channel (AWGN). The communication link was simulated by using Matlab, which shows the theoretical systems efficiency. Then the data stream was input as data to be simulated communication systems using Matlab. The purpose of this paper is to introduce the audience to a simulation technique that has been successfully used to determine how well a FEC expected to work when transferring digital data streams. The goal is to use this data to show how FEC optimizes a digital data stream to gain a better digital communications systems. The results conclude by making comparisons of different possible styles for the Tornado FEC code.
Date: May 2011
Creator: Noriega, Alexandra
Partner: UNT Libraries

Hamiltonian cycles in subset and subspace graphs.

Description: In this dissertation we study the Hamiltonicity and the uniform-Hamiltonicity of subset graphs, subspace graphs, and their associated bipartite graphs. In 1995 paper "The Subset-Subspace Analogy," Kung states the subspace version of a conjecture. The study of this problem led to a more general class of graphs. Inspired by Clark and Ismail's work in the 1996 paper "Binomial and Q-Binomial Coefficient Inequalities Related to the Hamiltonicity of the Kneser Graphs and their Q-Analogues," we defined subset graphs, subspace graphs, and their associated bipartite graphs. The main emphasis of this dissertation is to describe those graphs and study their Hamiltonicity. The results on subset graphs are presented in Chapter 3, on subset bipartite graphs in Chapter 4, and on subspace graphs and subspace bipartite graphs in Chapter 5. We conclude the dissertation by suggesting some generalizations of our results concerning the panciclicity of the graphs.
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Date: December 2004
Creator: Ghenciu, Petre Ion
Partner: UNT Libraries

Graphical Recoupling of Angular Momenta

Description: Report presenting a diagrammatic method for solving angular momentum recoupling problems. It is shown that a few graphical elements with a set of rules for their use lead to the solution of many types of recoupling problems in an intuitive and systematic way. Several examples are given together with exercises to develop the reader's facility with the method.
Date: October 1973
Creator: Lehman, D. R. & O'Connell, J. S.
Partner: UNT Libraries Government Documents Department

Applications of Rapidly Mixing Markov Chains to Problems in Graph Theory

Description: In this dissertation the results of Jerrum and Sinclair on the conductance of Markov chains are used to prove that almost all generalized Steinhaus graphs are rapidly mixing and an algorithm for the uniform generation of 2 - (4k + 1,4,1) cyclic Mendelsohn designs is developed.
Date: August 1993
Creator: Simmons, Dayton C. (Dayton Cooper)
Partner: UNT Libraries

Using Normal Deduction Graphs in Common Sense Reasoning

Description: This investigation proposes a powerful formalization of common sense knowledge based on function-free normal deduction graphs (NDGs) which form a powerful tool for deriving Horn and non-Horn clauses without functions. Such formalization allows common sense reasoning since it has the ability to handle not only negative but also incomplete information.
Date: May 1992
Creator: Munoz, Ricardo A. (Ricardo Alberto)
Partner: UNT Libraries

Massive graph visualization : LDRD final report.

Description: Graphs are a vital way of organizing data with complex correlations. A good visualization of a graph can fundamentally change human understanding of the data. Consequently, there is a rich body of work on graph visualization. Although there are many techniques that are effective on small to medium sized graphs (tens of thousands of nodes), there is a void in the research for visualizing massive graphs containing millions of nodes. Sandia is one of the few entities in the world that has the means and motivation to handle data on such a massive scale. For example, homeland security generates graphs from prolific media sources such as television, telephone, and the Internet. The purpose of this project is to provide the groundwork for visualizing such massive graphs. The research provides for two major feature gaps: a parallel, interactive visualization framework and scalable algorithms to make the framework usable to a practical application. Both the frameworks and algorithms are designed to run on distributed parallel computers, which are already available at Sandia. Some features are integrated into the ThreatView{trademark} application and future work will integrate further parallel algorithms.
Date: October 1, 2007
Creator: Wylie, Brian Neil & Moreland, Kenneth D.
Partner: UNT Libraries Government Documents Department

Intelligent Memory Management Heuristics

Description: Automatic memory management is crucial in implementation of runtime systems even though it induces a significant computational overhead. In this thesis I explore the use of statistical properties of the directed graph describing the set of live data to decide between garbage collection and heap expansion in a memory management algorithm combining the dynamic array represented heaps with a mark and sweep garbage collector to enhance its performance. The sampling method predicting the density and the distribution of useful data is implemented as a partial marking algorithm. The algorithm randomly marks the nodes of the directed graph representing the live data at different depths with a variable probability factor p. Using the information gathered by the partial marking algorithm in the current step and the knowledge gathered in the previous iterations, the proposed empirical formula predicts with reasonable accuracy the density of live nodes on the heap, to decide between garbage collection and heap expansion. The resulting heuristics are tested empirically and shown to improve overall execution performance significantly in the context of the Jinni Prolog compiler's runtime system.
Date: December 2003
Creator: Panthulu, Pradeep
Partner: UNT Libraries

Exercise your visual thinking. [Graphic representation in publishing]

Description: Figures and tables are a means of presenting high-density information in a pleasing manner. Editors who exercise their visual thinking can improve dense, uninviting reports by suggesting meaningful illustrations for an author's approval. Illustrations can clarify descriptive passages or even replace them. Editors are urged to sketch what they think is needed. Examples of selecting information for graphic representation are given and the appropriateness of a photograph, illustration, graph, or logic diagram is discussed.
Date: January 1, 1982
Creator: Amsden, D.C.
Partner: UNT Libraries Government Documents Department

[Man works at a computer]

Description: Photograph of a man working at his computer in his office. Charts, graphics and other data is displayed on the computer screen while another man looks on.
Date: May 5, 2015
Creator: Clark, Junebug
Location Info:
Partner: UNT Libraries Special Collections