Digital Commons Network^™

High Breakdown Strength, Multilayer Ceramics For Compact Pulsed Power Applications, Wayne Huebner, Brian L. Gilmore, Shi C. Zhang, Mike L. Krogh, B. C. Schultz, R. C. Pate, L. F. Rinehart, J. M. Lundstrom

Materials Science and Engineering Faculty Research & Creative Works

Advanced ceramics are being developed for use in large area, high voltage devices in order to achieve high specific energy densities (greater than 10^6/ J/m^3/) and physical size reduction. Initial materials based on slip cast TiO2 exhibited a high bulk breakdown strength (BDS greater than 300 kV/cm) and high permittivity with low dispersion (epsilon approximately equal to 100). However, strong area and thickness dependencies were noted. To increase the BDS, multilayer dielectric compositions are being developed based on glass/TiO2 composites. The addition of glass increases the density (approximately equal to 99.8% theoretical), forms a continuous grain boundary phase, and also …

Measurement Of The Dielectric Strength Of Titanium Dioxide Ceramics, Wayne Huebner, J. M. Lundstrom, L. F. Rinehart, R. C. Pate, T. L. Smith, Mike L. Krogh

Materials Science and Engineering Faculty Research & Creative Works

Titanium dioxide ceramics (TiO2) are candidate materials for high energy density pulsed power devices. Experiments to quantify the dielectric strength of TiO2 have been performed on a limited number of unoptimized samples. A high voltage test set was constructed to test the titanium dioxide. All samples had a relative dielectric constant of 100, all samples were of 3 mm nominal thickness, and all tests were performed in water dielectric to reduce the effect of the triple point field enhancement at the electrode edge. Both single layer and laminated samples were tested and the breakdown field strengths were recorded. Voltage risetimes …

Structural Disorder And The Origin Of High-Tc Suppression In La₁.₈₇₅Ba₀.₁₂₅ Cuo4−Δ, Daniel Haskel, Edward A. Stern, Fatih Dogan, Arnie R. Moodenbaugh

Materials Science and Engineering Faculty Research & Creative Works

Polarized x-ray absorption fine structure (XAFS) measurements at all La, Ba and Cu sites were used to study local structural features that accompany the strong Tc suppression at: r,,, 1/8 in La₂BaCuO₄. Two critical parameters regulating the strength of hole-lattice coupling in this material were determined, ie, the direction and magnitude of CuO₆ octahedra local tilts. Our findings include the existence of large disorder in the magnitude of the tilt angle about its average value (0), with an rms~~ 2 (0). We suggest that this large disorder strongly scatters a large fraction of states at …

X-Ray Absorption, Neutron Diffraction, And Mössbauer Effect Studies Of Mnzn-Ferrite Processed Through High-Energy Ball Milling, D. J. Fatemi, V. G. Harris, Mingxing Chen, Satish K. Malik, William B. Yelon, Gary J. Long, Amitabh Mohan

Physics Faculty Research & Creative Works

MnZn-ferrite has been prepared via high-energy ball milling of elemental oxides MnO, ZnO, and α-Fe₂O₃. Neutron diffraction measurements suggest a high density of vacancies in a spinel structure. The spinel phase appears to comprise 99.8 wt % of the material in the sample milled for 40 h, with the remainder attributable to unreacted α-Fe₂O₃. The x-ray absorption near-edge structure was analyzed to provide an understanding of the charge state of the constituent Fe ions. This analysis reveals about 2/3 of Fe cations to be trivalent, increasing to about 3/4 after a 5 …

Magnetic And Crystallographic Properties Of Lani₅₋ₓfex, C. Tan, Oran Allan Pringle, Mingxing Chen, William B. Yelon, J. Gebhardt, Naushad Ali, C. Y. Tai, G. K. Marasinghe, George Daniel Waddill, William Joseph James

Physics Faculty Research & Creative Works

No abstract provided.

Nuclear Fuel Pellet Inspection Using Artificial Neural Networks, Shahla Keyvan, Xiaolong Song, Mark Kelly

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Nuclear fuel must be of high quality before being placed into service in a reactor. Fuel vendors currently use manual inspection for quality control of fabricated nuclear fuel pellets. In order to reduce workers' exposure to radiation and increase the inspection accuracy and speed, the feasibility of automation of fuel pellet inspection using artificial neural networks (ANNs) is studied in this paper. Three kinds of neural network architectures are examined for evaluation of the ANN performance in proper classification of good versus bad pellets. Two supervised neural networks, back-propagation and fuzzy ARTMAP, and one unsupervised neural network called ART2-A are …

Mechanisms For The Formation Of Rhythmic Topography In The Nearshore Region, Giovanni Coco

School of Biological and Marine Sciences Theses

The possibility that the periodic features observed in the nearshore region are the result of self-organisational processes is investigated in this work. The behaviour of two numerical models, based on different techniques, has been analysed in order to describe the formation of periodic features in the surf and swash zone respectively. The appearance of periodic patterns in the nearshore region has been traditionally linked to the presence of standing edge waves with the topographic changes passively driven by the flow patterns. A more recent approach indicates the possibility that periodic patterns appear because of feedback processes between beach morphology and …

The Hygrothermal Response And Physical Aging Of Polymer Matrix Textile Composites, Natalie L. Dixon

Masters Theses

"Woven graphite/epoxy composite laminate is one type of composite currently being investigated for use in aircraft engine components. However, polymers tend to become brittle with age, especially when exposed to elevated temperature. It is necessary to understand the physical changes in a material during the aging process in order to predict the long-term behavior.

In addition to aging, materials used in aircraft will be exposed to a wide variety of temperatures and relative humidity levels. Variations in temperature and moisture content affect both the physical and the mechanical properties of composites.

Experimental methods are described for hygrothermal testing of a …

Arbitration, Kristen Angus

Denver Law Review

No abstract provided.

Vol. 76, No. 3: Full Issue, Denver University Law Review

Denver Law Review

No abstract provided.

Influence Of Chemical Reactions In Magnesia-Graphite Refractories: I, Effects On Texture And High-Temperature Mechanical Properties, Carmen Baudín, Carlos Alvarez, Robert E. Moore

Materials Science and Engineering Faculty Research & Creative Works

Four formulations of magnesia-graphite-aluminum metal (antioxidant) bricks were prepared from the same raw materials, using the standard commercial practices. Chemical analysis and determination of room-temperature modulus of rupture and Young's modulus, as well as a complete microstructural characterization of the as-received materials, were performed. For high-temperature modulus-of-rupture and Young's modulus data, test samples of the four brick compositions were heated to 1000°, 1200°, and 1450 °C in flowing argon (< 1000 ppm oxygen at 1000 °C) and then loaded mechanically in flexure. Modulus-of-elasticity values ranged from 3.7 to 16.2 GPa and reflected strong effects of aluminum-metal concentration and treatment temperature. Young's modulus evolution with temperature was determined by the evolution of the micro-structure in the bulk of the specimens. Modulus-of-rupture values ranged from 6 to 21 MPa, and their evolution with temperature was determined by the evolution of the micro-structure in the bulk of the specimens at the lower testing temperatures (T≤1200 °C) and by phase assemblages in the surface regions of the specimens - essentially by the presence of the dense MgO zone - at 1450 °C.

Influence Of Chemical Reactions In Magnesia-Graphite Refractories: Ii, Effects Of Aluminum And Graphite Contents In Generic Products, Carmen Baudín, Carlos Alvarez, Robert E. Moore

Materials Science and Engineering Faculty Research & Creative Works

A group of magnesia-graphite and magnesia-graphite-aluminum materials, the compositions of which represent a wide range of graphite contents (approximately 10-16.4 wt.%), aluminum contents (0-5.2 wt.%), and MgO and graphite qualities, were fabricated, using standard commercial practices. Chemical analysis and determination of room-temperature modulus of rupture (MOR) and Young's modulus, as well as a complete microstructural characterization of the as-received materials, were performed. Mechanical characterization at high temperature (1000°, 1200°, and 1450 °C) was done in terms of Young's modulus and MOR in an argon atmosphere (°C). Modulus-of-elasticity values ranged from 4 to 16 GPa, and their evolution with temperature was …

Copper Nucleation On Titanium For Thin Film Applications, A. J.B. Dutra, Thomas J. O'Keefe

Materials Science and Engineering Faculty Research & Creative Works

Copper nucleation and growth on titanium substrates from concentrated acidic copper sulfate solutions was studied at 45 and 65 °C and high cathodic potentials. Electrochemical experiments allied to SEM examination were performed to characterize the mechanism of nucleation and its evolution with time. Particular emphasis was given to the influence of potential and agitation on the initial stages of nucleation and growth. Results indicated that most of copper nucleation on titanium from a 83 g dm-3 Cu2+ solution, at 65 °C, is achieved in a matter of milliseconds. As expected, the initial stages of the copper nucleation and growth is …

University Of Missouri--Rolla Self-Study Prepared For The North Central Association Of Colleges And Schools, University Of Missouri--Rolla

Self-Study for North Central Association accreditation

This document has been developed as a part of the planning processes ongoing within the University of Missouri-Rolla (UMR) community and the University of Missouri (UM) System In 1993, the four-campus UM System conducted a significant planning effort under the aegis of the University’s Board of Curators focusing on program review, which involved a detailed setting of academic priorities Within the past two years, the four- campus system has, based on inclusive planning, established priorities for additional support from the State of Missouri under a "mission enhancement" effort Further, the UMR campus has a well-developed annual planning cycle which produces …

Leisure, The Basis Of Culture [Review] / Josef Pieper; New Translation By Gerald Malsbary., Johhny Ramirez

Andrews University Seminary Studies (AUSS)

No abstract provided.

Development Of Odour-Baited Traps For Glossina Swynnertoni (Diptera: Glossinidae), P. N. Ndegwa, S. Mihok

All Peer-Reviewed Publications

Three new prototype traps, (S1-S3), were developed during studies of the behavioural ecology of Glossina swynnertoni Austen in Kenya and Tanzania. The traps were compared in latin square experiments relative to the regular biconical trap as a standard and a selection of other conventional tsetse traps. Observations were also made on fly behaviour in the vicinity of traps using electric nets and sticky materials. When baited with acetone and 1-octen-3-ol, the S1 trap was 3.5 times as effective in catching G. swynnertoni in Kenya as the biconical trap. In Tanzania, the relative performance of the S1 and biconical traps differed; …

Workplace Sexual Harassment In Singapore: The Legal Challenge, Jack Tsen-Ta Lee

Research Collection Yong Pung How School Of Law

This article examines the nature and prevalence of sexual harassment in the work environment, and compares civil and criminal law in Singapore to the approaches taken by various jurisdictions in dealing with the problem. It is submitted that legislation is needed to protect employees, as Singapore law currently does not present any clear and coherent means for victims to seek redress for workplace sexual harassment.

User-Responsivity And Environment-Sensitivity Consideration For State-Funded Housing In Alain City, Nassra Saif Al Daheri

Theses

Massive housing projects have shown that prospective users are rarely given the opportunity to participate in the design decisions. Subsequently, such schemes commonly fail to accommodate all their needs. In the Emirate of Abu Dhabi, the housing projects that aim at resettling of Bedouin into newly developed urban communities are state-funded. Many of these houses that were built in the late seventies and early eighties were transferred back to the state (in a very bad condition due to the users random modifications and additions) in exchange of newer better houses. The lack of an adaptive design concept that can accommodate …

An Analysis Of Sustained Collaborative Research Activities Between University Organized Research Units And Industry: A Case Study Of Three Institutions, Elizabeth Taraski Mcdonnell

Seton Hall University Dissertations and Theses (ETDs)

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A Study Of Job Satisfaction Among Urban Superintendents In New Jersey, Richard J. Malanowski

Seton Hall University Dissertations and Theses (ETDs)

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Perceptions Regarding Knowledge Management: An Exploration Of Characteristics And Components Of Knowledge Management With Application In The Pharmaceutical Industry, Michael D. Sutch

Seton Hall University Dissertations and Theses (ETDs)

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High-Performance Bus-Based Architectures - Guest Editorial, Stephan Olariu, Rong Lin

Computer Science Faculty Publications

(First paragrapg) This special issue of VLSI Design presents a collection of seven papers selected out of more than 35 submissions received following the Call for Papers. Each submission was sent to three referees, all of them experts in the area of bus-based architectures. The result is impressive. The papers featured in this Special Issue cover a wide range of topics from sorting to string matching, to load balancing, to simulation, matrix operations, to robotics, to the design of high-performance scalable architectures.

Need Help Asap!! A Call For The Development Of Online Research Guidelines And Protocols, G. Jon Hall, Douglas J. Frederick

Iowa Journal of Communication

The use of electronic forums for research has recently been recognized and encouraged. Research via Usenet saves time, is convenient, and is accessible 24 hours per day. Moreover, electronic forums may serve as a potential research site for virtually any topic in any discipline. However, research methodology has failed to keep pace with technological advancement. Application of traditional research methods to electronic forums often are inappropriate and injurious to member-participants. The development of research methodology by trial and error is irresponsible. This study, an outgrowth of an actual case study, seeks to call attention to the need for protocols and …

The Dichotomy Between Standards And Rules, Mary C. Daly

Vanderbilt Journal of Transnational Law

The differences in perception between U.S. and foreign lawyer codes of conduct is more than simply a matter of academic interest or curiosity. It is only a matter of time until the WTO turns its attention to the codes, examining whether and to what extent they create illegitimate regulatory barriers to trade in legal services. As the participants in the Forum on Transnational Legal Practice have come to realize, if the legal profession is to play a meaningful role in cross-border regulation, it must seize the initiative, much as the CCBE did in 1988 with the adoption of the CCBE …

Emerging Leader Of The Tax Avant-Garde, Andrzej J. Burba

Vanderbilt Journal of Transnational Law

In 1998, Poland's Minister of Finance Leszek Balcerowicz unveiled a plan to restructure the tax system. His fiat tax proposal promises numerous benefits to individual and corporate taxpayers with significant reduction in tax rates for both groups. The new plan offers to further strengthen Poland's growing economy--a consequence that is especially significant in light of the country's aspiration to join the European Union. It provides a remedy for virtually every ailment plaguing the current tax system and, most importantly, the reform offers to finance itself This Note argues that the plan should be adopted immediately for the following reasons: (1) …

Iowa Academy Of Science Membership Directory, 1999-2000, Iowa Academy Of Science

Iowa Academy of Science Documents

Contents:

Editorial Board, Journal ... 5
Committees ... 6
Sections ... 18
ISTS Regional Directors ... 22
Awards of Merit ... 24
Excellence in Science Teaching Awards ... 25
Past Presidents ... 26
Membership Roster ... 27
Corporate Sponsors ... 70

The Role Of Artists In Ship Camouflage During World War I, Roy R. Behrens

Faculty Work

Experiments in ship camouflage during World War I were necessitated by the inordinate success of German submarines (called "U-boats") in destroying Allied ships. Because it is impossible to make a ship invisible at sea, Norman Wilkinson, Everett L. Warner and other artists devised methods of course distortion in which high-contrast, unrelated shapes were painted on a ship's surface, thereby confusing the periscope view of the submarine gunner.

Surface Resistance Measurements Of Superconducting Niobium Samples With A Triaxial Cavity, Paul Martin Boccard

Physics Theses & Dissertations

This experimental study has revealed and investigated many of the physical issues that affect accurate measurement of the surface resistance for small samples consisting of superconducting niobium films on copper substrates. It is believed that this work provides the groundwork for future research directed towards solving this important problem. Accurate measurement of surface resistance for such samples is needed to allow the rapid evaluation and optimization of the deposition parameters necessary for manufacturing low-loss superconducting niobium films.

A superconducting niobium triaxial cavity was investigated to determine its suitability for measuring the residual surface resistance of copper samples that were sputter-coated …

Smart Objects, Dumb Archives: A User-Centric, Layered Digital Library Framework, Kurt Maly, Michael L. Nelson, Mohammad Zubair

Computer Science Faculty Publications

Discusses digital libraries, interoperability, and interfaces to access them, and proposes one universal protocol for communication for simple archives based on the hypertext transfer protocol (http). Describes the creation of a special class of digital objects called buckets, archives based on a NASA collection, and a set of digital library services. (Author/LRW)

Smoking : An Exploration Of Message Framing And Death Anxiety, Ian James Parker

Theses : Honours

The focus of this thesis is the replication and extension of research by Tversky and Kahneman (1981) who found that how a message is worded or framed can significantly affect decisional choice. Tversky and Kahneman (1981) demonstrated that a message framed in terms of "lives saved" was favoured over one which read "lives lost" notwithstanding that the net sum of survivors was equal in both instances. The authors referred to the effects of message framing on decision making as Prospect Theory. This thesis studied Tversky and Kahneman's (1981) research applied to the issue of smoking. The preference for a positive …