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High Flying To Tailspin: Otto E. Szekely And His Troubled Aircraft And Engine Company, Geoffrey D. Reynolds Jan 2001

High Flying To Tailspin: Otto E. Szekely And His Troubled Aircraft And Engine Company, Geoffrey D. Reynolds

Faculty Publications

Otto E. Szekely and His Troubled Aircraft and Engine Company is an article concering Hungarian native Otto E. Szekely and his short success as a builder of Flying Dutchman aircraft and Szekely aicraft engines in Holland, Michigan, from the 1920s to the 1930s.

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Not So Different: Tangible, Intangible, Digital, And Analog Works And Their Comparison For Copyright Purposes, I. Trotter Hardy Jan 2001

Not So Different: Tangible, Intangible, Digital, And Analog Works And Their Comparison For Copyright Purposes, I. Trotter Hardy

Faculty Publications

No abstract provided.

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Carter, Reagan, And Khomeini: Presidential Transitions And International Law, Nancy Amoury Combs Jan 2001

Carter, Reagan, And Khomeini: Presidential Transitions And International Law, Nancy Amoury Combs

Faculty Publications

No abstract provided.

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Soft-X-Ray Fluorescence Study Of The Quasi-One-Dimensional Heisenberg Antiferromagnet Tetraphenylverdazyl, E. Z. Kurmaev, V. R. Galakhov, S. Shimada, T. Otsuka, K. Endo, S. Stadler, D. L. Ederer, A. Moewes, H. Schuerman, M. Neumann, S. Tomiyoshi, N. Azuma, M. Iwami Dec 2000

Soft-X-Ray Fluorescence Study Of The Quasi-One-Dimensional Heisenberg Antiferromagnet Tetraphenylverdazyl, E. Z. Kurmaev, V. R. Galakhov, S. Shimada, T. Otsuka, K. Endo, S. Stadler, D. L. Ederer, A. Moewes, H. Schuerman, M. Neumann, S. Tomiyoshi, N. Azuma, M. Iwami

Faculty Publications

Soft-x-ray fluorescence measurements have been performed on a single crystal of the organic antiferromagnet 2,4,6-triphenylverdazyl. Resonant and nonresonant C Kα and N Kα (2p → 1s transition) x-ray emission spectra (XES) were measured and compared with x-ray photoelectron valence band spectra and deMon density-functional theory calculations. It is shown that intramolecular interactions are much stronger than intermolecular ones and give the main contribution to the formation of C 2p density of states. We present evidence of a delocalization of unpaired N 2p electrons over the verdazyl ring. The excitation energy dependence of C Kα and N Kα XES observed below …

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High-Quality P-N Junctions With Quaternary Alingan/Ingan Quantum Wells, A. Chitnis, A. Kumar, M. Shatalov, V. Adivarahan, A. Lunev, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur Dec 2000

High-Quality P-N Junctions With Quaternary Alingan/Ingan Quantum Wells, A. Chitnis, A. Kumar, M. Shatalov, V. Adivarahan, A. Lunev, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur

Faculty Publications

We report on quaternary AlInGaN/InGaN multiple quantum well(MQW)light emitting diode structures grown on sapphire substrates. The structures demonstrate high quality of the p–njunctions with quaternary MQW. At low forward bias (below 2 V), the temperature dependent of current–voltage characteristics are exponential with the ideality factor of 2.28, which is in a good agreement with the model of the injected carrier recombination in the space charge region. This ideality factor value is approximately three times lower than for conventional GaN/InGaN light emitting diodes(LEDs). The obtained data indicate the recombination in p–njunction space charge region to be responsible for a current transport …

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The Role Of Intelligent Transportation Systems (Its) In Intermodal Air Cargo Operations, H.-S. Jacob Tsao, Asim Rizwan Dec 2000

The Role Of Intelligent Transportation Systems (Its) In Intermodal Air Cargo Operations, H.-S. Jacob Tsao, Asim Rizwan

Faculty Publications

If California were a nation, it would be the sixth largest economy in the world. Efficient goods movement is crucial to California’s economy. Air freight consists predominantly of high-value, time-sensitive or time-definite goods, e.g., electronic equipment, emergency shipments, overnight packages, etc. Timely delivery of air freight has been an important element of many manufacturing and service operations in California. Therefore, the air cargo industry is a vital part of the state’s economy. The objectives of this research include (a) investigating and suggesting how the public sector in California can assist the air cargo industry in providing efficient services to businesses …

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Biomedical Research Leaders: Report On Needs, Opportunities, Difficulties, Education And Training, And Evaluation, Samuel H. Wilson, Deborah Brown, Jay Moskowitz, Dan Hurley, David Brown, David Brown, Byron J. Bailey, Michael Mcclain, Marilyn Misenhimer, Judith Buckalew, Thomas Burks Dec 2000

Biomedical Research Leaders: Report On Needs, Opportunities, Difficulties, Education And Training, And Evaluation, Samuel H. Wilson, Deborah Brown, Jay Moskowitz, Dan Hurley, David Brown, David Brown, Byron J. Bailey, Michael Mcclain, Marilyn Misenhimer, Judith Buckalew, Thomas Burks

Faculty Publications

The National Association of Physicians for the Environment (NAPE) has assumed a leadership role in protecting environmental health in recent years. The Committee of Biomedical Research Leaders was convened at the recent NAPE Leadership Conference: Biomedical Research and the Environment held on 1–2 November 1999, at the National Institutes of Health, Bethesda, Maryland. This report summarizes the discussion of the committee and its recommendations. The charge to the committee was to raise and address issues that will promote and sustain environmental health, safety, and energy efficiency within the biomedical community. Leaders from every important research sector (industry laboratories, academic health …

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Effect Of Gate Leakage Current On Noise Properties Of Algan/Gan Field Effect Transistors, S. L. Rumyantsev, N. Pala, M. S. Shur, R. Gaska, M. E. Levinshtein, M. Asif Khan, Grigory Simin, X. Hu, J. Yang Dec 2000

Effect Of Gate Leakage Current On Noise Properties Of Algan/Gan Field Effect Transistors, S. L. Rumyantsev, N. Pala, M. S. Shur, R. Gaska, M. E. Levinshtein, M. Asif Khan, Grigory Simin, X. Hu, J. Yang

Faculty Publications

The effect of the gate leakage current fluctuations on noiseproperties of AlGaN/GaN heterostructurefield effect transistors(HFETs) has been studied in conventional HFET structures and in AlGaN/GaN metal-oxide-semiconductorheterostructurefield effect transistors (MOS-HFETs). The comparison of the noiseproperties of conventional AlGaN/GaN HFETs and AlGaN/GaN MOS-HFETs fabricated on the same wafer, allowed us to estimate the contribution of the gate currentnoise to the HFET’s output noise. The effect of the gate current fluctuations on output noiseproperties of HFETs depends on the level of noise in the AlGaN/GaN HFETs. For the transistors with a relatively high magnitude of the Hooge parameter α∼10−3, even a …

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Finite-Aperture Wire Grid Polarizers, Michael A. Jensen, Gregory P. Nordin Dec 2000

Finite-Aperture Wire Grid Polarizers, Michael A. Jensen, Gregory P. Nordin

Faculty Publications

The transmission characteristics of wire grid polarizers fabricated in finite apertures are investigated by using a three-dimensional finite-difference time-domain formulation. Specifically, the optical transmissivity and extinction ratio are characterized for a wide variety of geometrical parameters including aperture size in both dimensions, conducting wire fill factor, and polarizer thickness. A dispersive material model is used to investigate the performance of polarizers fabricated by using realistic metals at infrared wavelengths. The results indicate that the aperture dimension significantly impacts the polarizer transmission behavior and that the extinction of the unwanted polarization is often limited by depolarizing scattering that is due to …

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Direct Generation Of Optical Diffractive Elements In Perfluorocyclobutane (Pfcb) Polymers By Soft Lithography, Gregory P. Nordin, J. Ballato, P. C. Deguzman, S. Foulger, H. Shah, D. Smith Dec 2000

Direct Generation Of Optical Diffractive Elements In Perfluorocyclobutane (Pfcb) Polymers By Soft Lithography, Gregory P. Nordin, J. Ballato, P. C. Deguzman, S. Foulger, H. Shah, D. Smith

Faculty Publications

Optically diffractive line gratings with 0.58- m feature sizes have been generated in 100- m perfluorocyclobutane (PFCB) polymer films by direct micromolding using only a silicon master. Strong reflectivities from the green to red portions of the visible spectrum, depending on incident beam angle, were observed with 3 dB bandwidths of approximately 30 nm. This negative mold-free technique permits, for the first time to our knowledge, feature reproduction at submicrometer size scales, eliminates several steps from conventional soft lithographic methods, and marks itself as a practical means for rapidly generating planar photonic structures that operate spectrally in the visible and …

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Erratum: Magnetoresistance From Quantum Interference Effects In Ferromagnets (Nature (2000) 404 (581-584)), N. Manyala, Y. Sidis, J. F. Ditusa, G. Aeppli, D. P. Young, Z. Fisk Nov 2000

Erratum: Magnetoresistance From Quantum Interference Effects In Ferromagnets (Nature (2000) 404 (581-584)), N. Manyala, Y. Sidis, J. F. Ditusa, G. Aeppli, D. P. Young, Z. Fisk

Faculty Publications

No abstract provided.

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Molecular Dynamics Calculations Of The Electrochemical Properties Of Electrolyte Systems Between Charged Electrodes, Richard L. Rowley, Paul S. Crozier, Douglas Henderson Nov 2000

Molecular Dynamics Calculations Of The Electrochemical Properties Of Electrolyte Systems Between Charged Electrodes, Richard L. Rowley, Paul S. Crozier, Douglas Henderson

Faculty Publications

We investigate the interfacial electrochemical properties of an aqueous electrolyte solution with discrete water molecules in slab geometry between charged atomistic electrodes. Long-range intermolecular Coulombic interactions are calculated using the particle particle particle mesh method with a modification to account for the slab geometry. Density distribution profiles and potential drops across the double layer are given for 0, 0.25, and 1 M aqueous electrolyte solutions each electrode surface charges. Results are compared qualitatively with experimental x-ray scattering findings, other computer simulation results, and traditional electrochemistry theory. The interfacial fluid structure characteristics are generally in good qualitative agreement with the conclusions …

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Kinetic Characterization Of His-Tagged Cp47 Photosystem Ii In Synechocystis Sp. Pcc6803, Zhao Liang Li, Terry M. Bricker, Robert Burnap Nov 2000

Kinetic Characterization Of His-Tagged Cp47 Photosystem Ii In Synechocystis Sp. Pcc6803, Zhao Liang Li, Terry M. Bricker, Robert Burnap

Faculty Publications

Recently, construction of strains of Synechocystis sp. PCC6803 having a His6 extension (His-tag) of the carboxyl terminus of the CP47 protein has been reported (T.M. Bricker et al, Biochim. Biophys. Acta 1409 (1998) 50; M.J. Reifler et al., in: Garab, Pusztai (Eds.) Proc. XIth International Congress on Photosynthesis, 1998). While these initial reports suggest a minimal impact of the His-tag upon Photosystem (PS) II function, a more thorough analysis of the kinetic properties of the modified complex is essential. This communication reports on a more detailed kinetic analysis to assess possible perturbations of PS II due to the genetic addition …

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Parallel Phylogenetic Inference, Mark J. Clement, David Mclaughlin, Quinn O. Snell, Michael Whiting Nov 2000

Parallel Phylogenetic Inference, Mark J. Clement, David Mclaughlin, Quinn O. Snell, Michael Whiting

Faculty Publications

Recent advances in DNA sequencing technology have created large data sets upon which phylogenetic inference can be performed. However, current research is limited by the prohibitive time necessary to perform tree search on even a reasonably sized data set. Some parallel algorithms have been developed but the biological research community does not use them because they don’t trust the results from newly developed parallel software. This paper presents a new phylogenetic algorithm that allows existing, trusted phylogenetic software packages to be executed in parallel using the DOGMA parallel processing system. The results presented here indicate that data sets that currently …

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Toward Automated Abstraction For Protocols On Branching Networks, Michael D. Jones, Ganesh Gopalakrishnan Nov 2000

Toward Automated Abstraction For Protocols On Branching Networks, Michael D. Jones, Ganesh Gopalakrishnan

Faculty Publications

We have used various manual abstraction techniques to formally verify a transaction ordering property for an IO protocol over bus/bridge networks. In the context of network protocol verification, an abstraction is needed to reduce the unbounded number of network configurations to a small number of representative networks that can be checked using algorithmic methods. The manually derived abstraction was both brittle and difficult to validate. In this report, we discuss the need for abstraction techniques in the formal verification of protocols over networks and present our recent efforts to create an automatic abstraction technique for network protocols using predicate abstraction …

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Mission College, Thailand, Assignment: October 26 - November 8, 2000, Keith Clouten Nov 2000

Mission College, Thailand, Assignment: October 26 - November 8, 2000, Keith Clouten

Faculty Publications

This report tells the story of a library consultation visit to Mission College, a new Adventist post-secondary school situated in the hill country northeast of Bankok, Thailand.

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Hop Integrity In Computer Networks, Mohamed G. Gouda, E.N. Elnozahy, Chin-Tser Huang, Tommy M. Mcguire Nov 2000

Hop Integrity In Computer Networks, Mohamed G. Gouda, E.N. Elnozahy, Chin-Tser Huang, Tommy M. Mcguire

Faculty Publications

A computer network is said to provide hop integrity iff when any router p in the network receives a message m supposedly from an adjacent router q, then p can check that m was indeed sent by q, was not modified after it was sent, and was not a replay of an old message sent from q to p. We describe three protocols that can be added to the routers in a computer network so that the network can provide hop integrity. These three protocols are a secret exchange protocol, a weak integrity protocol, and a strong integrity protocol. All …

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High Performance Micropane Electron Beam Window, Roger A. Dougal, Shengyi Liu Nov 2000

High Performance Micropane Electron Beam Window, Roger A. Dougal, Shengyi Liu

Faculty Publications

A silicon disk etched so that it contains a multitude of microscopic and thin window panes (micropanes) can potentially transmit a larger average electron beam current density and absorb a smaller fraction of the beam energy than a common metal foil window. The enhanced performance is achieved by a combination of decreased power loss due to the extremely small window thickness (~1 μm), and increased conductive cooling due to the small diameter (~50 μm) of the micropanes and the large cross section of the honeycomb structure that supports the micropanes. Beam current densities up to 34 A/cm2 are permitted within …

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System Level Microwave Design: Radar-Based Laboratory Projects, Michael A. Jensen, David V. Arnold, Donald E. Crockett Nov 2000

System Level Microwave Design: Radar-Based Laboratory Projects, Michael A. Jensen, David V. Arnold, Donald E. Crockett

Faculty Publications

Two laboratory projects-a Doppler radar and a synthetic aperture radar (SAR)-designed to augment traditional electromagnetics education are proposed. The projects introduce students to component and system level design and expose them to modern computer-aided design (CAD) tools, microstrip and surface mount fabrication technologies, and industry standard test equipment and procedures. Additionally, because the projects result in a working radar system, students gain new enthusiasm for the electromagnetics discipline and directly see its relevance in the engineering field. Implementation of these laboratories within the curriculum have proven to be highly motivational and educational and have even contributed to increased enrolments in …

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Enhanced Luminescence In Ingan Multiple Quantum Wells With Quaternary Alingan Barriers, Jianping Zhang, J. Yang, Grigory Simin, M. Shatalov, M. Asif Khan, M. S. Shur, R. Gaska Oct 2000

Enhanced Luminescence In Ingan Multiple Quantum Wells With Quaternary Alingan Barriers, Jianping Zhang, J. Yang, Grigory Simin, M. Shatalov, M. Asif Khan, M. S. Shur, R. Gaska

Faculty Publications

We report on the comparative photoluminescence studies of AlGaN/GaN, GaN/InGaN, and AlInGaN/InGaN multiple quantum well(MQW) structures. The study clearly shows the improvement in materials quality with the introduction of indium. Our results point out the localized state emission mechanism for GaN/InGaN structures and the quantum well emission mechanism for AlInGaN/InGaN structures. The introduction of indium is the dominant factor responsible for the observed differences in the photoluminescence spectra of these MQW structures.

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High Electron Mobility In Algan/Gan Heterostructures Grown On Bulk Gan Substrates, E. Frayssinet, W. Knap, P. Lorenzini, N. Grandjean, J. Massies, C. Skierbiszewski, T. Suski, I. Grzegory, S. Porowski, Grigory Simin, X. Hu, M. Asif Khan, M. S. Shur, R. Gaska, D. Maude Oct 2000

High Electron Mobility In Algan/Gan Heterostructures Grown On Bulk Gan Substrates, E. Frayssinet, W. Knap, P. Lorenzini, N. Grandjean, J. Massies, C. Skierbiszewski, T. Suski, I. Grzegory, S. Porowski, Grigory Simin, X. Hu, M. Asif Khan, M. S. Shur, R. Gaska, D. Maude

Faculty Publications

Dislocation-free high-quality AlGaN/GaN heterostructures have been grown by molecular-beam epitaxy on semi-insulating bulk GaN substrates. Hall measurements performed in the 300 K–50 mK range show a low-temperature electron mobility exceeding 60 000 cm2/V s for an electron sheet density of 2.4×1012 cm−2. Magnetotransport experiments performed up to 15 T exhibit well-defined quantum Hall-effect features. The structures corresponding to the cyclotron and spin splitting were clearly resolved. From an analysis of the Shubnikov de Hass oscillations and the low-temperature mobility we found the quantum and transport scattering times to be 0.4 and 8.2 ps, respectively. The …

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Preparation Of Mesoporous Sno2-Sio2 Composite As Electrodes For Lithium Batteries, Fanglin Chen, Zhong Shi, Meilin Liu Oct 2000

Preparation Of Mesoporous Sno2-Sio2 Composite As Electrodes For Lithium Batteries, Fanglin Chen, Zhong Shi, Meilin Liu

Faculty Publications

Mesoporous SnO2–SiO2 composite stable up to 600 °C with a BET surface area of 350 m2 g-1 and an average pore size of 3.4 nm is successfully prepared, which exhibits promising cycling properties as anodes for lithium batteries

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Preparation Of Mesoporous Yttria-Stabilized Zirconia (Ysz) And Ysz-Nio Using A Triblock Copolymer As Surfactant, Fanglin Chen, Meilin Liu Oct 2000

Preparation Of Mesoporous Yttria-Stabilized Zirconia (Ysz) And Ysz-Nio Using A Triblock Copolymer As Surfactant, Fanglin Chen, Meilin Liu

Faculty Publications

Mesoporous yttria-stabilized zirconia (YSZ) and YSZ-NiO have been prepared for the first time using Pluronic P103 as a structure-directing agent and inorganic chlorides as precursors in a nonaqueous medium. After being fired at 500°C for 2 h, mesostructured YSZ has a BET surface area of about 146 m2 g-1, with an average pore size of 3.8 nm, while mesostructured YSZ-NiO has a BET surface area of about 108 m2 g-1, with an average pore size of 4.5 nm.

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Optical Bandgap Formation In Alingan Alloys, G. Tamulaitis, K. Kazlauskas, S. Juršėnas, A. Žukauskas, M. A. Khan, J. W. Yang, J. Zhang, Grigory Simin, M. S. Shur, R. Gaska Oct 2000

Optical Bandgap Formation In Alingan Alloys, G. Tamulaitis, K. Kazlauskas, S. Juršėnas, A. Žukauskas, M. A. Khan, J. W. Yang, J. Zhang, Grigory Simin, M. S. Shur, R. Gaska

Faculty Publications

We report on the spectral dynamics of the reflectivity, site-selectively excited photoluminescence,photoluminescence excitation, and time-resolved luminescence in quaternary AlInGaN epitaxial layers grown on GaN templates. The incorporation of a few percents of In into AlGaN causes significant smoothening of the band-bottom potential profile in AlInGaN layers owing to improved crystal quality. An abrupt optical bandgap indicates that a nearly lattice-matched AlInGaN/GaN heterostructure with large energy band offsets can be grown for high-efficiency light-emitting devices.

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The Business Lawyer As Terrorist Transaction Cost Engineer, Royce De R. Barondes Oct 2000

The Business Lawyer As Terrorist Transaction Cost Engineer, Royce De R. Barondes

Faculty Publications

Lawyers have garnered a reputation for being unreasonable and excessively contentious. This popular sentiment is embedded in our culture. If lawyers cannot change that perception, a second-best outcome (from the perspective of lawyers) would be the formation of an understanding that there is a reason why they appear to act unreasonably, that it can be desirable for lawyers to act in a way that initially appears to be unreasonable. This Article attempts to build a basis for that understanding in the context of lawyers participating in large commercial transactions.

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Chinese Privatization: Between Plan And Market, Lan Cao Oct 2000

Chinese Privatization: Between Plan And Market, Lan Cao

Faculty Publications

No abstract provided.

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A Dynamic Optimal Trajectory Generator For Cartesian Path Following, Edward Red Sep 2000

A Dynamic Optimal Trajectory Generator For Cartesian Path Following, Edward Red

Faculty Publications

This paper considers a dynamic and adaptive trajectory generator for negotiating paths using S-curves. Applying constant jerk transitions between the constant acceleration and deceleration periods of the trajectory, the trajectory will optimally transition to the desired speed setting. Optimal is defined to be the minimum time to transition from the current speed to the set speed for the move segment when jerk and acceleration are limited. The S-curve equations will adapt to instantaneous changes in speed setting and path length. An integrated motion planner will determine allowable speeds and transitional profiles based on the remaining move distance.

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The Monument To Brigham Young And The Pioneers : One Hundred Years Of Controversy, J. Michael Hunter Sep 2000

The Monument To Brigham Young And The Pioneers : One Hundred Years Of Controversy, J. Michael Hunter

Faculty Publications

For more than a century, the Brigham Young Monument in Salt Lake City has been the center of sometimes acrimonious controversy. The idea and organization to create a monument were begun in 1891. The statue of Brigham Young was completed by Cyrus Dallin in 1893. Many delays in raising funds caused the monument not to be finished until 1900. Thereafter it often became the target of those trying to improve traffic conditions in the downtown area. In 1993, the monument was moved just north of the intersection to improve the flow of traffic. On the monuments one hundredth anniversary, "The …

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Algan/Gan Metal-Oxide-Semiconductor Heterostructure Field-Effect Transistors On Sic Substrates, M. Asif Khan, X. Hu, A. Tarakji, Grigory Simin, J. Yang, R. Gaska, M. S. Shur Aug 2000

Algan/Gan Metal-Oxide-Semiconductor Heterostructure Field-Effect Transistors On Sic Substrates, M. Asif Khan, X. Hu, A. Tarakji, Grigory Simin, J. Yang, R. Gaska, M. S. Shur

Faculty Publications

We report on AlGaN/GaN metal–oxide–semiconductor heterostructurefield-effect transistors (MOS-HFETs) grown over insulating 4H–SiC substrates. We demonstrate that the dc and microwave performance of the MOS-HFETs is superior to that of conventional AlGaN/GaN HFETs, which points to the high quality of SiO2/AlGaNheterointerface. The MOS-HFETs could operate at positive gate biases as high as +10 V that doubles the channel current as compared to conventional AlGaN/GaN HFETs of a similar design. The gate leakage current was more than six orders of magnitude smaller than that for the conventional AlGaN/GaN HFETs. The MOS-HFETs exhibited stable operation at elevated temperatures up to 300 …

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Gettysburg: An Exhibit For The First-Year Reading Experience, Patrick G. Scott Aug 2000

Gettysburg: An Exhibit For The First-Year Reading Experience, Patrick G. Scott

Faculty Publications

Based on an exhibition for University of South Carolina students reading Michael Shaara's bestselling book The Killer Angels, this catalogue recounts the story of the battle of Gettysburg day by day, with an opening section introducing the major participants and a final section dealing with the commemoration of the battle and its treatment in later American literature. All the items in the exhibition are drawn from the Francis A. Lord Civil War Collection and the Robert S. Chamberlain Military History Collection, both in Rare Books & Special Collections, University of South Carolina Libraries.

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