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An Integral Equation For Dissipative Quantum Transport, Supriyo Datta, Michael J. Mclennan Mar 1989

An Integral Equation For Dissipative Quantum Transport, Supriyo Datta, Michael J. Mclennan

Department of Electrical and Computer Engineering Technical Reports

We present an integral equation derived under the simplifying assumption that the inelastic scattering is caused by uncorrelated point scatterers, such as magnetic impurities or impurities with internal degrees of freedom. While this assumption is not always realistic, we believe that the model can be used to describe much of the essential physics of quantum transport in mesoscopic systems. This assumption allows us to write a transport equation that involves only the electron density and not the spatial correlations of the wave function. The kernel of this integral equation is calculated from the Schrodinger equation and contains all quantum interference …

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Sequal 2.1 User’S Manual, M. J. Mclennan, S. Datta Mar 1989

Sequal 2.1 User’S Manual, M. J. Mclennan, S. Datta

Department of Electrical and Computer Engineering Technical Reports

SEQUAL is a device simulation program which performs a quantum mechanical analysis of electron transport. The user need not be an expert in quantum mechanics to obtain useful results from this program, although an understanding of the subject is an invaluable aid in the interpretation of output. For this reason,, the theoretical formulation of the analysis is presented in some detail, following a brief introduction. The knowledgeable (or anxious) user may turn directly to the discussions of input and output in Chapters 3 and 4. The reader is cautioned, however, not to skip Chaper 2 entirely. At the heart of …

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3d Location Of Circular And Spherical Features By Monocular Model-Based Vision, Y. C. Shiu, Shaheen Ahmed Mar 1989

3d Location Of Circular And Spherical Features By Monocular Model-Based Vision, Y. C. Shiu, Shaheen Ahmed

Department of Electrical and Computer Engineering Technical Reports

This paper addresses the mathematics for using monocular model-based vision to find the 3-D positions of circular and spherical model features, and, for the circular case, orientations as well. Monocular model-based vision here refers to the use of a single projective image of modeled objects to solve for the 3-D positions and orientations of the objects in the scene. The mathematics for solving 3-dimensional position and orientation of the object from matched model and image points/lines features are well known. However, no known paper addresses spherical features arid very few papers address the mathematics involving circular model features. This paper …

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Description Of Semilog, Ryan Stanisfer, Chul Hung, Andrew B. Whinston, Parthasarathy Bhasker Feb 1989

Description Of Semilog, Ryan Stanisfer, Chul Hung, Andrew B. Whinston, Parthasarathy Bhasker

Department of Computer Science Technical Reports

No abstract provided.

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Preemptive Ensemble Motion Planning On A Tree, Gred N. Frederickson, D. J. Guan Feb 1989

Preemptive Ensemble Motion Planning On A Tree, Gred N. Frederickson, D. J. Guan

Department of Computer Science Technical Reports

No abstract provided.

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Increasing The Efficiency Of Vector Itpack, Robert E. Lynch Feb 1989

Increasing The Efficiency Of Vector Itpack, Robert E. Lynch

Department of Computer Science Technical Reports

No abstract provided.

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An Algorithm For Computing S-Invariants For High Level Petri Nets, Chuang Lin, Dan C. Marinescu Feb 1989

An Algorithm For Computing S-Invariants For High Level Petri Nets, Chuang Lin, Dan C. Marinescu

Department of Computer Science Technical Reports

No abstract provided.

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Sequence Comparison Of The Connection Machine, Mikhail J. Atallah, Scott Mcfaddin Feb 1989

Sequence Comparison Of The Connection Machine, Mikhail J. Atallah, Scott Mcfaddin

Department of Computer Science Technical Reports

No abstract provided.

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Disc: A Method For Dynamic Intelligent Scheduling And Control Of Reconfigurable Parallel Architectures, F. J. Weil, L. H. Jamieson, E. J. Delp Feb 1989

Disc: A Method For Dynamic Intelligent Scheduling And Control Of Reconfigurable Parallel Architectures, F. J. Weil, L. H. Jamieson, E. J. Delp

Department of Electrical and Computer Engineering Technical Reports

This work studies the use of intelligence-guided control of reconfigurable parallel processing systems. A reconfigurable architecture is one that can be partitioned into several independent virtual parallel machines operating in either SIMD or MIMD mode. Reconfigurable systems, while allowing great flexibility, present many scheduling and control problems. Scheduling tasks on such a system is an exponential time problem. Therefore, in an effort to achieve reduced, task execution time without incurring unacceptable scheduling costs, an expert system is used to apply heuristics to approximate an optimal schedule. When the execution time of a task is not known a priori, conventional scheduling …

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Critical Path Analysis Of Real-Time Ada Programs, Dan C. Marinescu, Ryan Stansifer Feb 1989

Critical Path Analysis Of Real-Time Ada Programs, Dan C. Marinescu, Ryan Stansifer

Department of Computer Science Technical Reports

No abstract provided.

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On Variable Radius Blending Using Dupin Cyclides, Vijaya Chandru, Debasish Dutta, Christoph M. Hoffmann Jan 1989

On Variable Radius Blending Using Dupin Cyclides, Vijaya Chandru, Debasish Dutta, Christoph M. Hoffmann

Department of Computer Science Technical Reports

No abstract provided.

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Dex: A High Level Tool For Distributed System Experiments, Niraj K. Sharma, Jagannathan Srinivasan Jan 1989

Dex: A High Level Tool For Distributed System Experiments, Niraj K. Sharma, Jagannathan Srinivasan

Department of Computer Science Technical Reports

No abstract provided.

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On Grid Refinement At Point Singularities For H-P Methods, A. T. Chen, John R. Rice Jan 1989

On Grid Refinement At Point Singularities For H-P Methods, A. T. Chen, John R. Rice

Department of Computer Science Technical Reports

No abstract provided.

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Review: The Practical Tutor, David Chapman Jan 1989

Review: The Practical Tutor, David Chapman

The Writing Center Journal

No abstract provided.

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Bond Of Epoxy Coated Reinforcing Steel In Concrete Bridge Decks : Informational Report, Douglas Bruce Cleary, J. A. Ramirez Jan 1989

Bond Of Epoxy Coated Reinforcing Steel In Concrete Bridge Decks : Informational Report, Douglas Bruce Cleary, J. A. Ramirez

JTRP Technical Reports

No abstract provided.

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Construction Specifications For Highway Projects Requiring Horizontal Earth Boring And/Or Pipe Jacking Techniques, Donn Edward Hancher, Thomas D. White, David Thomas Iseley Jan 1989

Construction Specifications For Highway Projects Requiring Horizontal Earth Boring And/Or Pipe Jacking Techniques, Donn Edward Hancher, Thomas D. White, David Thomas Iseley

JTRP Technical Reports

No abstract provided.

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Scatchard Analysis Of Methane Sulfinic Acid Production From Dimethyl Sulfoxide: A Method To Quantify Hydroxyl Radical Formation In Physiologic Systems, Charles F. Babbs, David W. Griffin Jan 1989

Scatchard Analysis Of Methane Sulfinic Acid Production From Dimethyl Sulfoxide: A Method To Quantify Hydroxyl Radical Formation In Physiologic Systems, Charles F. Babbs, David W. Griffin

Weldon School of Biomedical Engineering Faculty Publications

A major impediment to the confirmation of free radical mechanisms in pathogenesis is a lack of direct, chemical evidence that oxygen centered free radicals actually arise in living tissues in quantities sufficient to cause serious damage. This investigation was conducted to validate the use of dimethyl sulfoxide (DMSO) as a quantitative molecular probe for the generation of hydroxyl radicals (HO*) under physiologic conditions. Reaction of HO* with DMSO produces methane sulfinic acid (MSA) as a primary product, which can be detected by a simple colorimetric assay. To develop a method for estimating total HO* production, we studied two model systems: …

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Consequences Of Valley Filtering On Abrupt Junction Algaas/Gaas Heterojunction Bipolar Transistors, Amitava Das, Mark S. Lundstrom Jan 1989

Consequences Of Valley Filtering On Abrupt Junction Algaas/Gaas Heterojunction Bipolar Transistors, Amitava Das, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

Electron transport in AlGaAs/GaAs heterojunction bipolar transistors with compositionally abrupt emitter‐base junctions is examined. Transport across the abrupt emitter‐base heterojunction is treated quantum mechanically, and the Monte Carlo technique is used to study transport through the base. Although there is a sizeable population of upper‐valley electrons in the bulk emitter, the AlGaAs/GaAs heterojunction is found to favor the injection of Γ‐valley electrons into the base. This valley filtering effect enhances device performance by reducing base transit time, but quantum mechanical tunneling lowers the average energy of the injected flux which increases base transit time. The design of a heterojunction bipolar …

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Ee Student Workstation Lab Status Report December, 1988, Michael E. Hussey, John C. Lindenlaub Jan 1989

Ee Student Workstation Lab Status Report December, 1988, Michael E. Hussey, John C. Lindenlaub

Department of Electrical and Computer Engineering Technical Reports

The Maclab project in the Spring of 1988 demonstrated that providing a Macintosh workstation environment to some sections of EE 267 (Digital Logic Design Laboratory) was both useful and feasible on a small scale. The goals of the EE Student Workstation project this past Summer and Fall were: A. To provide all sections of EE 267 (approximately 200 students) with a Macintosh workstation environment for the simulation of digital logic circuits and for the preparation of reports. B. Tb provide a useful Macintosh workstation environment to other Electrical Engineering students. C. To transfer responsibility for operational aspects of the Macintosh …

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Effect Of Oxygen Concentration On The Formation Of Malondialdehyde-Like Material In A Model Of Tissue Ischemia And Reoxygenation, Steven C. Salaris, Charles F. Babbs Jan 1989

Effect Of Oxygen Concentration On The Formation Of Malondialdehyde-Like Material In A Model Of Tissue Ischemia And Reoxygenation, Steven C. Salaris, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

This study was conducted to explore the functional relationship between oxygen concentration during tissue reoxygenation after ischemia and the extent of postischemic lipid peroxidation, an indicator of reoxygenation injury. Excised rat liver or kidney tissue was rendered ischemic for 1 h at 37°C, minced into 1 mm3 fragments, and then reoxygenated for 1 h in flasks of buffered salt solution containing various amounts of oxygen. Production of malondialdehyde-like material (MDA) was measured to indicate lipid peroxidation. MDA production was minimal at oxygen tensions less than 10 mmHg, increased sharply from 10 to 50 mmHg, and plateaued at approximately 100 mmHg. …

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Lethal Hydroxyl Radical Production In Paraquat-Treated Plants, Charles F. Babbs, Jo Ann Pham, Ronald C. Coolbaugh Jan 1989

Lethal Hydroxyl Radical Production In Paraquat-Treated Plants, Charles F. Babbs, Jo Ann Pham, Ronald C. Coolbaugh

Weldon School of Biomedical Engineering Faculty Publications

Bipyridinium herbicides, including paraquat and diquat, are believed to act by generating highly reactive, oxygen-centered free radicals within chloroplasts when treated plants are exposed to sunlight. This hypothesis has not yet been confirmed by direct chemical measurements of specific free radicals. We studied paraquat-treated plants using a new method able to detect and quantify formation of highly reactive and deleterious hydroxyl radicals (HO*), in which dimethyl sulfoxide (DMSO) is used as a molecular probe. DMSO is oxidized by HO* to form the stable, nonradical compound, methane sulfinic acid, which can be easily extracted from plant tissue and measured spectrophotometrically. Initial …

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Measurements Of Carrier Generation-Recombination Parameters In Silicon Solar Cell Material Using Mos Techniques, W. M/ Au, R. F. Pierret, R. J. Schwartz, F. Sanii Jan 1989

Measurements Of Carrier Generation-Recombination Parameters In Silicon Solar Cell Material Using Mos Techniques, W. M/ Au, R. F. Pierret, R. J. Schwartz, F. Sanii

Department of Electrical and Computer Engineering Technical Reports

Modified and new measurement techniques were developed for determining the carrier generation-recombination (G-R) parameters in silicon solar cell material under carrier deficit and low-level carrier excess conditions using MOS-based test structures. The structures mainly consisted of ring-dot MOS Capacitors (MOS-C) and Schottky-Drained Gate-Controlled Diodes (SGCD). Sample G-R parameters were extracted from n-type high quality silicon solar cell material. Additional measurements were also performed on low-quality ntype silicon substrates for comparison purposes. The photoaccelerated MOS-C Capacitance-time (C-t) transient measurement technique, modified from the standard C-t method, allows one to drastically reduce the observation time in deducing the carrier generation lifetime (Tg) …

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Supporting Shared Data Structures On Distributed Memory Architectures, Chalres Koelbel, Piyush Mchrotra Jan 1989

Supporting Shared Data Structures On Distributed Memory Architectures, Chalres Koelbel, Piyush Mchrotra

Department of Computer Science Technical Reports

No abstract provided.

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Classroom And Writing Center Collaborations: Peers As Authorities, Lisa Smulyan, Kristin Bolton Jan 1989

Classroom And Writing Center Collaborations: Peers As Authorities, Lisa Smulyan, Kristin Bolton

The Writing Center Journal

No abstract provided.

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Issues In The Writing Lab: An Eric/Rcs Report, Hilary Taylor Holbrook Jan 1989

Issues In The Writing Lab: An Eric/Rcs Report, Hilary Taylor Holbrook

The Writing Center Journal

No abstract provided.

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Checklist Of Recent Writing Center Scholarship: April 1988-March 1989, David W. Chapman Jan 1989

Checklist Of Recent Writing Center Scholarship: April 1988-March 1989, David W. Chapman

The Writing Center Journal

No abstract provided.

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Talking It Over: A Qualitative Study Of Writing Center Conferencing, Willa Wolcott Jan 1989

Talking It Over: A Qualitative Study Of Writing Center Conferencing, Willa Wolcott

The Writing Center Journal

No abstract provided.

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We're All Basic Writers: Tutors Talking About Writing Apprehension, Wendy Bishop Jan 1989

We're All Basic Writers: Tutors Talking About Writing Apprehension, Wendy Bishop

The Writing Center Journal

No abstract provided.

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Review: The Practical Tutor, Harvey Kail Jan 1989

Review: The Practical Tutor, Harvey Kail

The Writing Center Journal

No abstract provided.

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Ethical Issues In Peer Tutoring: A Defense Of Collaborative Learning, Richard Behm Jan 1989

Ethical Issues In Peer Tutoring: A Defense Of Collaborative Learning, Richard Behm

The Writing Center Journal

No abstract provided.

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