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1995

Electrical and Computer Engineering

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Articles 31 - 60 of 60

Full-Text Articles in Physical Sciences and Mathematics

A Unified Topological Approach To Electromagnetic Environmental Effects Protection, George H. Baker, J. Philip Castillo, Edward F. Vance Jun 1995

A Unified Topological Approach To Electromagnetic Environmental Effects Protection, George H. Baker, J. Philip Castillo, Edward F. Vance

George H Baker

The presentation recommends an approach for unifying electronic system protection designs for a wide spectrum of electromagnetic environments. A general electromagnetic topological construct is developed as the basis for a consistent shielding and terminal protection methodology. Spectral characteristics of multiple interfering electromagnetic sources, both internal and external, are described. Effects addressed include EMI/EMC, lightning, nuclear EMP, and RF weapons. Protection practices for individual effects are discussed and means for integrating these into a single protection topology.

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Optimal Mixed-Norm Control Synthesis For Discrete-Time Linear Systems, David R. Jacques Jun 1995

Optimal Mixed-Norm Control Synthesis For Discrete-Time Linear Systems, David R. Jacques

Theses and Dissertations

A mixed-norm approach to control synthesis for discrete time linear systems is developed. Specifically, the problem of minimizing the H2 norm of a transfer function, subject to a combination of ℓ1 and-or H∞ norm constraints on dissimilar but related transfer functions is considered. The uniqueness of the optimal solution is shown, and numerical methods for approximating the optimal solution to within arbitrary accuracy are developed. These methods generally result in high order compensators which can not be implemented in most practical applications. In response to this, a numerical method is developed which solves for suboptimal solutions of …

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Laser Scanning In-Situ Photoelectrochemical Microscopictechnique And Its Applications, Zugeng Lin, Jinkua You, Xiangdong Zhuo, Chun Zhang, Yong Yang May 1995

Laser Scanning In-Situ Photoelectrochemical Microscopictechnique And Its Applications, Zugeng Lin, Jinkua You, Xiangdong Zhuo, Chun Zhang, Yong Yang

Journal of Electrochemistry

Abstract The main factors of the laser scanning in-situ photoelectrochemical microscopicmeasurement system which is set up in our lab have been discusaed in this paper. Some applications ofthis technique for insttn study of medificiition and processing of semiconductor electrodes , monitoringof electredeposition process of semiconducting material and redox reaction occurring at metal oxideelectrodes have aiso been presented. The results have shown that the technique is very powerfui thatfor studing local photoelectrochemical properties of semiconductors and metal oxide electredes. Theseprovide important information on the micro structural and electronic properties in the solidlelectrolyteinterface.AbstractLaser scanning, Local photocurrent spectroscopy, Photoelectrochemical,Semiconductor electode

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An Indirect Electrochemical Oxidation Of Toluene──Anodic Oxidation Of Mn(Ⅱ) On The Lead Electrode, Zhonghua Wang, Qingmin Hua, Guaeai Chen May 1995

An Indirect Electrochemical Oxidation Of Toluene──Anodic Oxidation Of Mn(Ⅱ) On The Lead Electrode, Zhonghua Wang, Qingmin Hua, Guaeai Chen

Journal of Electrochemistry

The electrochemical oxidation of Mn (Ⅱ) to Mn(Ⅱ) in concentrated H_2SO_4(2￣8 mol . L-1) at lead electrede has been studied. It is found that the electrede surface is oxidized toPbO_2 in a direct electrochemical reaction, then PbO_2formed reacts with Mn (Ⅱ) in a chemicalreaction. Some effects involves current density , concentration of H_2SO_4 , temperature and conversionwere evaluated. The rule of electrogenerated Mn (Ⅲ) in flow electrolysis cell were determined atseveral conditions. The current efficiency at greater than 90% is obtained in general.

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Photoelectrochemical And Spectroelectrochemical Studies Oniron Oxide Ultrafine Particles, Maizhi Yang, Yongjun Ji, Wen Zhang, Shengmin Cai May 1995

Photoelectrochemical And Spectroelectrochemical Studies Oniron Oxide Ultrafine Particles, Maizhi Yang, Yongjun Ji, Wen Zhang, Shengmin Cai

Journal of Electrochemistry

in this paper, Raman spectra, photocurrent and the UV-VIS reflectance aremeasured for studying the α-Fe_2O_3ultrafine particles adsorbed on Pt electrode. The blue shifts ofRaman peaks demonstrate the size quantization effect for the particles of 50 nm in diameter ascompared with the bulk material. With the changing of the potential , the photocurrent decrcases as theUV-VIS reflectance increases, and vice-versa. Therefore, the potential not only affects the hargetransfer direcdtion in the interface of electrede/redox couple, but also influences the light absortion onthe surface of particles.According to the results of photoelectrochemistry, we suggest that the cathedicphotocurrent in the potential range of more …

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The Electrochemical Reduction Of 2-Ethylanthraquinone(2eaq), Yaobin Zhu May 1995

The Electrochemical Reduction Of 2-Ethylanthraquinone(2eaq), Yaobin Zhu

Journal of Electrochemistry

The process of electrochemical reduction of 2EAQ in DMSO is studied using CVand ESR methods in this work, Pt, Pd and some implanted materials are used as electrodes. Thequasi-rever+sible property of two electron transfer steps and their following homogeneous chemicalreactions are illustrated,The mechanism of the electrochemical red uction of 2 EAQ and the kineticparameters of the related steps are obtained. Having measured the influence of water content in thesystem, the effect of the proton donor is discussed. After comparising the experimental results witheach other these experiments gives us the idea that the replacement of metal Pd or some Pd-catalystswith pd-implanted …

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Horseradish Peroxidase/Poly-O- Phen Ylenediamine Mem Brane Electrode:Preparation And Properties, Dong Wei, Huihuang Wu May 1995

Horseradish Peroxidase/Poly-O- Phen Ylenediamine Mem Brane Electrode:Preparation And Properties, Dong Wei, Huihuang Wu

Journal of Electrochemistry

A horseradish peroxidase(HRP)/poly-o-phenylenediamine(PPD)membraneelectrede was prepared by electropolymerization of o-phenylenediamine on glassy carbon in pH 7.0phosphate buffer,the process of the enzyme immobilization was studied,The enzyme electredeobtained exhibits the activity to catalyze the electrored uction of hydrogen peroxide in the absence ofany electron transfer mediator.The red uction reaction occurs in the potential range of PPD redoxprocess,it was believed that the polymer participates in electron transfer of the enzyme.The enzymereaction kinetics at rotating H RP/PPD electrede was analysed,and the factors influencing kineticparameters were discussed.

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Studies On Low Temperature Performance Of Rechargeable Mh-Ni Batteries, Wenkuan Zhang, Jingxian Shi, Yu Wan Lou, Qiusheng Duan May 1995

Studies On Low Temperature Performance Of Rechargeable Mh-Ni Batteries, Wenkuan Zhang, Jingxian Shi, Yu Wan Lou, Qiusheng Duan

Journal of Electrochemistry

The Dependence of low temperature performance on the alloy composition andelectrolyte component for rechargeable MH-Ni batteries is studied, the suitable composition of alloyand electrofyte are founds.

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Electrochemically Modified Glassy Carbon Electrode And Determination Of Copper By Anodic Stripping Voltammetry, Jinrui Xu, Yie Liu, Xiurun Zhuang May 1995

Electrochemically Modified Glassy Carbon Electrode And Determination Of Copper By Anodic Stripping Voltammetry, Jinrui Xu, Yie Liu, Xiurun Zhuang

Journal of Electrochemistry

This paper reported the glassy carbon electrode modified by cyclic voltammetrybetween-0. 1and + 1. 5 V(vs. SCE)in an aqueous solution containing catechol,formaldehyde andtalium hydroxide. The modified electrode can be applied to the determination of copper(Ⅱ) in water,and its sensitivity is about 35 times higher than that of unmedified glassy carbon electrede, Thequantitative limit with this modified electrede is 0. 1 ng/ml.

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The Reduction Of Oxygen To Hydrogen Peroxide At The Poly(O-Phenylenediamine)-Filmed Electrode, Zhaoe Lu, Tiangeng Zhong, Guanyong Zhang May 1995

The Reduction Of Oxygen To Hydrogen Peroxide At The Poly(O-Phenylenediamine)-Filmed Electrode, Zhaoe Lu, Tiangeng Zhong, Guanyong Zhang

Journal of Electrochemistry

The poly(o-phenylenediamine)(PPD)filmed graphite electrode was formed byelectro-polymerization of o-phenylenediamine in acidified(pH=1)0.2 mol·L-1 Na_2SO_4 solutionusing the cyclic voltammetric methed. The catalytic effect of the electrcareduction of oxygen in acidsolution was demonstrated by the voltammogram of the electrede in the oxygen saturated acid solutionof Na_2SO_4. The current efficiency of the reduction of oxygen to hydrogen peroxide was determined byIhe electrolysis in a divided cell under the condition of constant current. The various effectsinfluencing the accm ulation of H_2O_2 in the catholyte were discussed.

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Studies On Coordination Behavior Of Dimethyl Sulfoxide In Complex Of Rare Earth With Cryptand, Shichang Liu May 1995

Studies On Coordination Behavior Of Dimethyl Sulfoxide In Complex Of Rare Earth With Cryptand, Shichang Liu

Journal of Electrochemistry

lectrochemical reduction reaction in the course of the titration of Eu ( 2.2.2)and Eu( 2.2)using strong bonding solvent,DMSO,in C_2H_4Cl_2 has been investigated by cyclicvoltammetry. The greater the concen tration of strong bonding solvent,the more negative the half-wave potentials for the reduction reaction are. The coordination number of Eu(2.2.2 ) and Eu(2.2)which are 2 and 3 respectively,with DMSO can be calculated,according to the relations betweenhalf -wave potentials and the variety of concentration of DMSO.

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Bandwidth And Additive Bandwidth Of Graphs, Maria Kujawski May 1995

Bandwidth And Additive Bandwidth Of Graphs, Maria Kujawski

Honors Capstone Projects and Theses

No abstract provided.

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Review: 'Integrated Optics: Design And Modeling,' By Reinhard Marz, Bradley D. Duncan Apr 1995

Review: 'Integrated Optics: Design And Modeling,' By Reinhard Marz, Bradley D. Duncan

Electro-Optics and Photonics Faculty Publications

My overall impression is that Integrated Optics: Design and Modeling will make a fine addition to almost anyone's collection of books on integrated optics. It will, however, serve its readers better as a reference book than as a text from which to first learn the basic concepts of integrated optics. I say this because the book is written at a fairly sophisticated technical level, though the author often moves rather quickly to the "bottom line" without providing material much beyond what is first necessary to introduce a problem or concept, and then a statement of the results and/or implications. It …

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The Study Of The Growth Processes Of The Oxides On Lead Electrodes In Sulfuric Acid Solution, Hesheng Zhai, Xuguang Chen, Jinkua You, Yong Yang, Zugeng Lin Feb 1995

The Study Of The Growth Processes Of The Oxides On Lead Electrodes In Sulfuric Acid Solution, Hesheng Zhai, Xuguang Chen, Jinkua You, Yong Yang, Zugeng Lin

Journal of Electrochemistry

The growth processes of PbO and PbO_2 on lead electrodes have been investigatedby using in-situ methods that are combined with temporary AC resistance measurment technique andin-situ laser scanning photoelectrochemical microscopy.It is found that a linear relationship existsbetween the electrode resistance(R)and￣(1/2) after the electrode is oxidized at +0.6 V(vs.Hg/H_2SO_4/35%H_2SO_4)for more than 5 min.This result suggests that the growth of PbO is well distributedduring the early stage of oxidation.The study by using laser scanning photoelectrochemical microscopyhas further proved this point.The results also show that the growth of PbO_2 takes place and develops.

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Electroreduction Of The Nittobenzene On Titanium Electrode Implanted With Palladium, Zhongda Wu, Xianjun Zhu, Hongsen Wang Feb 1995

Electroreduction Of The Nittobenzene On Titanium Electrode Implanted With Palladium, Zhongda Wu, Xianjun Zhu, Hongsen Wang

Journal of Electrochemistry

The titanium substrates were bombarded with 1×10￣(17)～5×10￣(17)ions·cm￣(-2) ofpalladium at the room temperature. The surface composition of implanted electrede and concentration-depth profiles of various elements were measured by AES. The electrored uction processes ofnitrobenzene(NB)in 0.1 mol/L NaOH solution at Pd/Ti electrodes have been investigated by cyclicvoltaivimetry.The results show that the palladium implanted titanium electrodes exhibit a high catalyticactivity in the electroreduction of NB. The NB radical anion,which is the product of one-electronelectroreduction of NB,was detected by ESR in-situ in conjunction with electrochemical methods. Aniline was also detected as a product of electroreduction of NB by using UV-spectra in-situ. According to the …

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Electroreduction Of Holmium Ion On Iron Electrde In Molten Cholorides, Qiqin Yang, Guankun Liu, Yuzhi Su Feb 1995

Electroreduction Of Holmium Ion On Iron Electrde In Molten Cholorides, Qiqin Yang, Guankun Liu, Yuzhi Su

Journal of Electrochemistry

The cyclic voltammetry,open circuit potential-time curve after poteritiostaticelectrolysis,current-time curve at potential step,x-ray diffraction and electron probe microanalysiswere used to investigate the electrode process of Ho(Ⅲ)reduced on iron electrode in molten chloridesand the phases of surface alloy layer.The Ho-Fe alloys are formed at first,and then the metallicholmium is deposited when Ho(Ⅲ)is reduced on iron electrede. The charge transfer is reversible. Thefree energies of formation for the four intermetallic compounds of Ho-Fe system,the diffusioncoefficients and diffusion activation energy of Ho in alloyed cathode are determined.

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A Photoelectrochemical Investigation Of Zirconium Oxide Film, Maizhi Yang Feb 1995

A Photoelectrochemical Investigation Of Zirconium Oxide Film, Maizhi Yang

Journal of Electrochemistry

A photoelectrochemical investigation has been carried out on zirconium initialoxide film and its oxide film grownanodically at constant rate up to different thickness. Both anodicand cathedic photocurrents on the photocurrent spectrum depended on the potential,but had littlerelation with the forming anedic films or measuring solutions. Photocurrent spectrum and photocurrenttransients suggested that the oxide films on zirconium were duplex layers structure. The internal layerwas ZrO_2 and the external layer ZrO_2·(H_2O)_n. The photocurrent included photogenerated carrier ininternal and external oxide films,as well as internal photoinjection process for electrons from thesubstrate metal into the electrode/electolyte interface reacting with the redox couple. The analysis …

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Electrocatalytic Oxidation Of Formaidehyde And Formic Acid On A Pt/Sb_(Ad) Electrode, Hong Li, Lincai Jiang, Xiong Jiang Feb 1995

Electrocatalytic Oxidation Of Formaidehyde And Formic Acid On A Pt/Sb_(Ad) Electrode, Hong Li, Lincai Jiang, Xiong Jiang

Journal of Electrochemistry

The electrocatalytic activity for the oxidation of formaldehyde and formic acid ona Sb-modified platinum (Pt/Sb_(ad))was investigated.Results showed that the Pt/Sb_(ad) electrode waselectrocatalytically more active than a Pt electrode in the anodic oxidation of formaldehyde and formicacid.In the case of formaldehyde,an oxidation peak appeared at a potential of ca.0.7V.During theoxidation of formic acid,a 4-fold increase in the 1st peak current was observed.The Sb-modifiedplatinum electrode was found to be most electrocatalytically active at a coverage of 0.75±0.05.Theelectrocatalytic activity of the Pt/Sb_(ad) electrode can be best explained in terms of the geometrical effect,which may lead to the inhibition of the formation of the …

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Synthesis Of Li_Xcoo_2 And Its Behaviour In Rechargeable Lithium Battery, Mingfeng Guo, Ruimin Yang, Zebo Zhang, Jincao Ye Feb 1995

Synthesis Of Li_Xcoo_2 And Its Behaviour In Rechargeable Lithium Battery, Mingfeng Guo, Ruimin Yang, Zebo Zhang, Jincao Ye

Journal of Electrochemistry

The Variations of crystal lattice parameters of Li_xCoO_2 during charge anddischarge have been st ud ied by XRD and AAR spectroscopy.It was found that the Li_xCoO_2 crystalvolume expanded during charge and contracted during discharge.The crystal lattice structure wasbroken because of the formation of Co_3O_4 when deeply charge.The variation of lattice parameter C_0value in cycling process was similar to that in charge process.The variation of 006 peak was the mostsensitive in every case.In case of preheating for 20 hours at 700℃ before operating hightemperature,the 006 peak obtained an enhancement obviously.It has had the good rechargeability inmeasurement of the cyclic voltammograms,the CV …

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The Catalytic Behavior For Ni-W Electrode Modified By Carbon Ion Beam Implantion, Jishuang Zhang, Yaojiao Lv, Qinglian Li Feb 1995

The Catalytic Behavior For Ni-W Electrode Modified By Carbon Ion Beam Implantion, Jishuang Zhang, Yaojiao Lv, Qinglian Li

Journal of Electrochemistry

The hydrogen evolution activity in acidic and basic mediums for Ni-W electrodemodified by carbon ion beam implantation was investigated.The experimental results show thiselectrode has superior catalytic activity for the hydrogen evolution reaction than that of the unmodifiedNi-electrode.Long period testing of electrolysis under high current density show that this electrode hasalonger useful life hence it is a practical electrode material.The temperature effect of electrocatalyticproperty was also inverstigated.The experimental regularities are explained on the basis of the formation of surface m uItialloys of Ni-W-WC.

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Electric Field Mapping System With Nanosecond Temporal Rosolution, F. E. Peterkin, R. Block, K. H. Schoenbach Jan 1995

Electric Field Mapping System With Nanosecond Temporal Rosolution, F. E. Peterkin, R. Block, K. H. Schoenbach

Bioelectrics Publications

The electric field dependence of the absorption coefficient in semi‐insulating GaAs at the absorption edge was measured in a high‐voltage pulsed experiment. Pulse duration was kept below 50 ns in order to avoid thermal effects. A GaAs laser diode was used as a probe light source with wavelength varied from 902 to 911 nm. For fields up to 40 kV/cm the absorption coefficient increased from 3 to 17 cm−1 at 902 nm, with smaller absolute increases evident at the longer wavelengths. Calculation from theory was consistent with this behavior. The spatial variation of the electric field was also recorded …

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Beam Dynamics In The Cebaf Superconducting Cavities, Zenghai Li Jan 1995

Beam Dynamics In The Cebaf Superconducting Cavities, Zenghai Li

Dissertations, Theses, and Masters Projects

This work is a study of beam dynamics in the CEBAF superconducting cavities under the influence of the fields generated by externally applied RF and beam particles.;A full 3-D modeling of the CEBAF 5-cell superconducting cavity is carried out. Details of the modeling with MAFIA are discussed. Multipole fields due to the asymmetric couplers are studied by means of 3-D Fourier transforms. The cavity steering and focusing of the multipole fields are studied. Experimental measurements of these effects are performed to validate the modeling. Evaluation of the cavity misalignment is discussed. The emittance degradation effects in the CEBAF superconducting linacs …

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Supralinear Photoconductivity Of Copper Doped Semi-Insulating Gallium Arsenide, K. H. Schoenbach, R. P. Joshi, F. Peterkin, R. L. Druce Jan 1995

Supralinear Photoconductivity Of Copper Doped Semi-Insulating Gallium Arsenide, K. H. Schoenbach, R. P. Joshi, F. Peterkin, R. L. Druce

Bioelectrics Publications

We report on the intensity dependent supralinear photoconductivity in GaAs:Si:Cu material. The results of our measurements show that the effective carrier lifetime can change over two orders of magnitude with variations in the intensity of the optical excitation. A threshold intensity level has been observed and can be related to the occupancy of the deep copper level. Numerical simulations have also been carried out to analyze the trapping dynamics. The intensity dependent lifetimes obtained from the simulations match the experimental data very well. Finally, based on the nonlinear intensity dependence of the effective lifetimes, a possible low‐energy phototransistor application for …

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Constrained Least-Squares Digital Image Restoration, Rajeeb Hazra Jan 1995

Constrained Least-Squares Digital Image Restoration, Rajeeb Hazra

Dissertations, Theses, and Masters Projects

The design of a digital image restoration filter must address four concerns: the completeness of the underlying imaging system model, the validity of the restoration metric used to derive the filter, the computational efficiency of the algorithm for computing the filter values and the ability to apply the filter in the spatial domain. Consistent with these four concerns, this dissertation presents a constrained least-squares (CLS) restoration filter for digital image restoration. The CLS restoration filter is based on a comprehensive, continuous-input/discrete- processing/continuous-output (c/d/c) imaging system model that accounts for acquisition blur, spatial sampling, additive noise and imperfect image reconstruction. The …

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Analysis And Extension Of Model-Based Software Executives, Keith E. Lewis Jan 1995

Analysis And Extension Of Model-Based Software Executives, Keith E. Lewis

Theses and Dissertations

This research developed a comprehensive description of the simulation environment of Architect, a domain-oriented application composition system being developed at the Air Force Institute of Technology to explore new software engineering technologies. The description combines information from several previous research efforts and Architect's source code into a single, comprehensive document. A critical evaluation of the simulation environment was also performed, identifying improvements and modifications that enhance Architecture's application execution capabilities by reducing complexity and execution time. The analysis was then taken one step further and presented extensions to the current simulation environment. The extensions included investigating the feasibility of mixed-mode …

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Hardware Assists For High Performance Computing Using A Mathematics Of Arrays, Hardy J. Pottinger, W. Eatherton, J. Kelly, T. Schiefelbein, Lenore Mullin, R. Ziegler Jan 1995

Hardware Assists For High Performance Computing Using A Mathematics Of Arrays, Hardy J. Pottinger, W. Eatherton, J. Kelly, T. Schiefelbein, Lenore Mullin, R. Ziegler

Electrical and Computer Engineering Faculty Research & Creative Works

Work in progress at the University of Missouri-Rolla on hardware assists for high performance computing is presented. This research consists of a novel field programmable gate array (FPGA) based reconfigurable coprocessor board (the Chameleon Coprocessor) being used to evaluate hardware architectures for speedup of array computation algorithms. These algorithms are developed using a Mathematics of Arrays (MOA). They provide a means to generate addresses for data transfers that require less data movement than more traditional algorithms. In this manner, the address generation algorithms are acting as an intelligent data prefetching mechanism or special purpose cache controller. Software implementations have been …

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Effects Of Large Aspect Ratios And Fluctuations On Hard X-Ray-Detection In Lower Hybrid Driven Divertor Tokamaks, Linda L. Vahala, George Vahala, Paul Bonoli Jan 1995

Effects Of Large Aspect Ratios And Fluctuations On Hard X-Ray-Detection In Lower Hybrid Driven Divertor Tokamaks, Linda L. Vahala, George Vahala, Paul Bonoli

Electrical & Computer Engineering Faculty Publications

It is shown that lower hybrid wave scattering from fluctuations plays a critical role in large aspect ratio divertor plasmas even through the edge density fluctuation levels are only at 1%. This is seen in the theoretically calculated electron power-density profiles which can be directly correlated to the standard experimental chordal hard x-ray profiles. It thus seems that fluctuation effects must be included in determining rf current-density profiles.

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Compensation And Characterization Of Gallium Arsenide, Randy A. Roush Jan 1995

Compensation And Characterization Of Gallium Arsenide, Randy A. Roush

Electrical & Computer Engineering Theses & Dissertations

The properties of transition metals in gallium arsenide have been previously investigated extensively with respect to activation energies, but little effort has been made to correlate processing parameters with electronic characteristics. Diffusion of copper in gallium arsenide is of technological importance due to the development of GaAs:Cu bistable photoconductive devices. Several techniques are demonstrated in this work to develop and characterize compensated gallium arsenide wafers. The material is created by the thermal diffusion of copper into silicon-doped GaAs. Transition metals generally form deep and shallow acceptors in GaAs, and therefore compensation is possible by material processing such that the shallow …

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Scanning-Tunneling-Microscopy Study Of Pb On Si(111), D. Tang, H. E. Elsayed-Ali, J. Wendelken, J. Xu Jan 1995

Scanning-Tunneling-Microscopy Study Of Pb On Si(111), D. Tang, H. E. Elsayed-Ali, J. Wendelken, J. Xu

Electrical & Computer Engineering Faculty Publications

Scanning-tunneling microscopy has been used to study temperature and coverage dependence of the structure of lead on the Si(111)-7×7 surface. For low Pb coverage, the Pb atoms favored the faulted sites. The ratio between the number of Pb atoms on faulted to unfaulted sites increased after sample annealing. An energy difference of 0.05 eV associated with a Pb atom on these two sites is estimated. The mobility of Pb atoms on Si(111) was observed at a temperature as low as 260°C for a coverage of 0.1 and 1 ML. © 1995 The American Physical Society.

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A Diamond Thin Film Flow Sensor, Sacharia Albin, John C. Hagwood, John B. Cooper, David L. Gray, Scott D. Martinson, Michael A. Scott Jan 1995

A Diamond Thin Film Flow Sensor, Sacharia Albin, John C. Hagwood, John B. Cooper, David L. Gray, Scott D. Martinson, Michael A. Scott

Electrical & Computer Engineering Faculty Publications

We present the results of theoretical modeling and experimental testing of a diamond thin film sensor for flow studies. It is shown that the high thermal conductivity of a diamond film can enhance the frequency response of the flow sensor. One-dimensional heat diffusion equation was solved using the finite difference method for determining the frequency response. Two different sensor structures were analyzed: a Ni film on a quartz substrate (Ni/Q) and an intermediate layer of diamond film between the Ni film and quartz substrate (Ni/D/Q). The theoretical model predicts a frequency response for the Ni/D/Q sensor higher than that of …

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