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Articles 5341 - 5370 of 6327

Full-Text Articles in Engineering

An Interdisciplinary Solar Energy Project, William J. Hutzel Jan 1996

An Interdisciplinary Solar Energy Project, William J. Hutzel

School of Engineering Technology Faculty Publications

An HVAC course, previously offered to students in Mechanical Engineering Technology (MET), has been re-structured to include students in Building Construction Management (BCM). A large project is always an integral part of this course, creating a unique opportunity for collaboration between two distinctly different groups of Technology students. This cooperation is particularly beneficial because MET and BCM graduates frequently cross paths during their professional careers. Many MET graduates operate and service heating, ventilating, and air conditioning equipment that was originally specified and installed by BCM graduates. This paper discusses and evaluates student interactions during a solar …

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Locating The Drainage Layer For Bituminous Pavements In Indiana, Hossam Farouk. Hassan, Thomas D. White Jan 1996

Locating The Drainage Layer For Bituminous Pavements In Indiana, Hossam Farouk. Hassan, Thomas D. White

JTRP Technical Reports

Pavement subsurface drainage and its effect on pavement performance has been a subject of interest since the 18th and 19th centuries. With no doubt the detrimental effects of heavy wheel loads on pavements with saturated base material is a significant factor. The consequence of subsurface water on pavement performance includes premature rutting, cracking, faulting, and increased roughness, all of which lead to a decrease in serviceability. This research study involves the evaluation of the drainage performance of three section configurations. The sections were built with a difference in the filter as well as the drainage layer. Indiana #5D, and #53 …

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Use Of Gps To Enhance Mapping By Photogrammetry, Robert D. Feeney, James Samuel Bethel, Boudewijn H. W. Van Gelder, Steve Johnson Jan 1996

Use Of Gps To Enhance Mapping By Photogrammetry, Robert D. Feeney, James Samuel Bethel, Boudewijn H. W. Van Gelder, Steve Johnson

JTRP Technical Reports

This research has sought to demonstrate the benefits of kinematic GPS in conjunction with photogrammetric aerial triangulation for mapping purposes. The work was performed with the existing INDOT aerial camera which is quite old, and while this affected the accuracy of the results, the demonstration of capability with a likely potential for excellent results was achieved. Ground point accuracies from the strip were in the sub-meter range with only a single control point. This is contrasted with full-model control requiring 50-80 control points for such a strip. In order to bring accuracies down to an acceptable level, i.e. sub decimeter, …

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Transients In Power Systems, M. Belkhayat, J. Edwards, N. Hoonchareon, O. Marte, D. Stenberg, E. Walters Dec 1995

Transients In Power Systems, M. Belkhayat, J. Edwards, N. Hoonchareon, O. Marte, D. Stenberg, E. Walters

Department of Electrical and Computer Engineering Technical Reports

Power system engineering largely focuses on steady state analysis. The main areas of power system engineering are power flow studies and fault studies - both steady state technologies. But the world is largely transient, and power systems are always subject to time varying and short lived signals. This technical report concerns several important topics in transient analyses of power systems. The leading chapter deals with a new analytical tool-wavelets-for power system transients. Flicker and electric are furnace transients are discussed in Chapters I1 and IV. Chapter 111 deals with transients from shunt capacitor switching. The concluding chapters deal with transformer …

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Stay-In-Place Deck Panels - Horizontal Shear Strength Of Bridge Deck Panels - Part 2, Phani Kumar Nukala, J. A. Ramirez, Robert H. Lee, Menashi D. Cohen Aug 1995

Stay-In-Place Deck Panels - Horizontal Shear Strength Of Bridge Deck Panels - Part 2, Phani Kumar Nukala, J. A. Ramirez, Robert H. Lee, Menashi D. Cohen

JTRP Technical Reports

One of the most economic methods of bridge deck construction consists of prestressed concrete deck panels used in stay-in-place forms in conjunction with the cast-in-place concrete topping instead of the traditional monolithic roadway deck slabs. The performance of this type of deck as a composite unit is only possible if the horizontal shear stress resulting from bending of the deck if effectively transferred across the interface of the two elements. It is assumed that horizontal shear stresses are transmitted across the interface due to bond between the precast panel and cast-in-place concrete acting in conjunction with the horizontal shear connectors …

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Stormwater Drainage Manual 1995, Christopher B. Burke, Thomas T. Burke Jul 1995

Stormwater Drainage Manual 1995, Christopher B. Burke, Thomas T. Burke

Indiana Local Technical Assistance Program (LTAP) Publications

This manual is a comprehensive catalog of procedures, design methods and criteria, and general background information which will enable the designer to quickly learn or review the basic principles of storm drainage design. Subjects included are the precipitation and hydrological cycle, runoff and its estimation, open channels, flow in gutters and inlets, stormwater storage, storm sewer system design, and computer applications for computing watershed runoff. Included in the appendices are basics of statistical analysis, fundamentals of hydraulics, a list of regulatory agencies and governmental bodies which may have jurisdiction over drainage projects, and TR-20 and TR-55 blank forms.

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Differential Current Switch Logic: A Low Power Dcvs Logic Family, Dinesh Somasekhar, Kaushik Roy Apr 1995

Differential Current Switch Logic: A Low Power Dcvs Logic Family, Dinesh Somasekhar, Kaushik Roy

Department of Electrical and Computer Engineering Technical Reports

We present a new logic family, Differential Current Switch Logic (DCSL) for implementing clocked CMOS circuits. The circuit is in principle a differential cascode voltage switch logic circuit (DCVS). In cornparimsonto other forms of' clocked DCVS, DCSL achieves better performance both in terms of power and speed by restricting internal voltage swings in the N tree. Automatic lock-out of inputs on completion of evaluation is a novel feature of the circuit and allows new implementation of logic functions and the possibility of operating with reduced voltage swings. SPICE simulattions carried out with. the MOSIS 1 . 2 process indicate that …

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Direction Of Arrival Estimation And Tracking Of Narrowband And Wideband Signals, A. Satish, Rangasami L. Kashyap Mar 1995

Direction Of Arrival Estimation And Tracking Of Narrowband And Wideband Signals, A. Satish, Rangasami L. Kashyap

Department of Electrical and Computer Engineering Technical Reports

The research addresses estimation and tracking of direction of arrival @OA) and associated parameters of narrowband and wideband signals impinging on a uniform linear array of sensors. The signals are modeled as sample functions of a Gaussian stochastic process. Computationally efficient, approximate maximum likelihood (ML) methods are developed for direction of arrival estimation of narrowband signals impinging on a large array of sensors. A new likelihood function is formulated based on a large M (# sensors) Taylor's series approximation of the original likelihood function. Asymptotic expressions for Cramer-Rao lower bounds on the DOA estimates are derived. From the positive definiteness …

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Detecting Stator And Rotor Winding Faults In Three-Phase Induction Machines, Jeffrey C. Robertson, Chee Mun Ong Mar 1995

Detecting Stator And Rotor Winding Faults In Three-Phase Induction Machines, Jeffrey C. Robertson, Chee Mun Ong

Department of Electrical and Computer Engineering Technical Reports

The purpose of this work is to investigate the efficiency of existing methods for on-line fault detection when applied to three-phase induction motors, spc:cifically to test known theoretical calculations of harmonics developed by certain types of faults experimentally. The work involves the development of equipment and test procedures needed and research of existing methods of fault detection. The experiments are cor~ductedb y planting a fault in a test induction machine and then performing a Fast Fourier Transform (FFT) on the line current. The processed data are then compared with those from the same test machine before the fault was planted. …

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Alternatives To The Current Aashto Standard Bridge Sections, Joseffa Viktoria Meir, Michael Ramon Cicciarelli, J. A. Ramirez, Robert H. Lee Feb 1995

Alternatives To The Current Aashto Standard Bridge Sections, Joseffa Viktoria Meir, Michael Ramon Cicciarelli, J. A. Ramirez, Robert H. Lee

JTRP Technical Reports

The main objective of this study was evaluate feasible alternatives to the current AASHTO bridge girders used in Indiana. This evaluation included precast pretensioned bridge girders for spans from 30 to 130 feet with girder spacing between 5 and 10 feet up to 12 feet for the longer spans. Other criteria included girder design concrete compressive strengths up to 7000 psi, 8” total concrete deck thickness with design strength of 4000 psi, grade 60 steel for slab reinforcement and stirrups and ½” special grade 270 low-relaxation strand for prestressing steel. Post-tensioning and pretensioned box girders were outside the scope of …

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A Summary Of Highway Revenues, Expenses, And Distributions: 1987 Through 1994, Herpicc Feb 1995

A Summary Of Highway Revenues, Expenses, And Distributions: 1987 Through 1994, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

This report shows the history of receipts, expenses and distributions of revenues that provide funding to all local governments for highway, road and street work.

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An Evaluation Of Lane Closure Strategies For Interstate Work Zones, Raktim Pal, Kumares C. Sinha Jan 1995

An Evaluation Of Lane Closure Strategies For Interstate Work Zones, Raktim Pal, Kumares C. Sinha

JTRP Technical Reports

A systematic procedure was developed in the present study that can be used to make a decision regarding the appropriate lane closure strategy at a particular interstate work zone. Four criteria were identified which influence such a decision, namely user travel time and vehicle operating cost, traffic control cost, safety, and contractors’ convenience. The influences of these criteria were aggregated using the Analytic Hierarchy Approach. The procedure developed in the present study is systematic in nature, simple to use and sensitive to the policy adopted by a transportation agency. A computer program, LANECLOSE, was developed which can be readily used …

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Asphalt Mix Design And Performance, Shakor Ramat Badaruddin, Thomas D. White Jan 1995

Asphalt Mix Design And Performance, Shakor Ramat Badaruddin, Thomas D. White

JTRP Technical Reports

Premature flexible pavement distress became a major concern in Indiana. As a result, a study was conducted investigating the major underlying factors. Pavement sections were investigated based on a factorial study with four factors comprised of climate, truck traffic, pavement base type, and wheel path. The distresses evaluated were rutting, thermal cracking and stripping. All were evaluated against control sections with zero distress. The pavement condition of each section was determined. Laboratory tests of field sample included physical properties, dynamic creep and recompaction. Results of the study indicate that the Asphalt Institute mix design criteria identify an asphalt content that …

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Concrete Pavement Crack And Seat Performance Overlay Design, Haiming Huang, Thomas D. White Jan 1995

Concrete Pavement Crack And Seat Performance Overlay Design, Haiming Huang, Thomas D. White

JTRP Technical Reports

The objective of this study is to develop guidelines and criteria for design and construction of overlays on cracked and seated concrete pavements. The main factors which are investigated in this study include number of the seated roller pass, weight of seating roller pass, weight of seating roller, thickness of overlay, fiber content and fiber layer location. Eleven test sections were constructed on I-65 and twenty two test sections were constructed on US-31. An extensive investigation was conducted involving both field and laboratory testing. Field investigations included pavement condition survey and non destructive testing (NDT) of the pavements using FWD …

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Behavior Of Concrete Bridge Decks And Slabs Reinforced With Epoxy Coated Steel, Hendy Oetih Hasan, J. A. Ramirez Jan 1995

Behavior Of Concrete Bridge Decks And Slabs Reinforced With Epoxy Coated Steel, Hendy Oetih Hasan, J. A. Ramirez

JTRP Technical Reports

Thirty-four slab specimens with splices and transverse steel were tested in the laboratory to evaluate the structural performance of concrete bridge decks reinforced with epoxy-coated steel. Thirty specimens were tested under fatigue loading, and four were tested monotonically. Evaluations were made by comparing the performance of uncoated bar concrete specimens with that of epoxy-coated specimens under service and ultimate load conditions. In addition, a field evaluation of six bridges was conducted to assess the in-service condition of concrete bridge decks reinforced with epoxy-coated steel in Indiana. The laboratory results indicated fewer but wider cracks in specimens with epoxy-coated reinforcement. No …

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Development Of Annual Permit Procedure For Overweight Trucks On Indiana Highways, Robert K. Whitford, David P. Moffett Jan 1995

Development Of Annual Permit Procedure For Overweight Trucks On Indiana Highways, Robert K. Whitford, David P. Moffett

JTRP Technical Reports

Overweight truck permitting in Indiana is presently done on a per trip basis. This study evaluated alternatives to each trip having to make a call to the INDOT permit office to gain a permit. The study was originally requested by the Indiana State Legislature under P.L. 122-1993 section 7 in response to delays in getting permits. The report’s six chapters are 1. Introduction and Summary 2. Review of Other States’ Permitting Systems 3. Framework for Policy Evaluation 4. Permits for Michigan Truck-Trains 5. Overweight and Overweight/Oversized Trucks 6. Implementation Suggestions – PLUS -- 7. Appendices. A Michigan Truck-Train is a …

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Fatigue Strength Of Girders With Tapered Covered Plates, Ahmed Farouk Hassan, Mark D. Bowman Jan 1995

Fatigue Strength Of Girders With Tapered Covered Plates, Ahmed Farouk Hassan, Mark D. Bowman

JTRP Technical Reports

This report represents results from a study to determine the fatigue strength of steel beams with welded partial-length cover plates. Results of an experimental investigation that examined the fatigue strength of various cracked cover plate end details that were subsequently repaired are presented. The repair methods investigated included a slip-critical bolted splice plate connection, air-hammer peening, and a combination of the previous two called a partial bolted splice connection. Also, an analytical model was developed to predict the fatigue behavior of a cover plate and detail that is repaired using one of the three repair methods investigated and which contains …

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Improved Strategies For Deploying Vehicle-Actuated Control At Isolated Signalized Intersections, Michael J. Cassidy, Yu-Hao Chuang, Jeffrey Dunn Vitale Jan 1995

Improved Strategies For Deploying Vehicle-Actuated Control At Isolated Signalized Intersections, Michael J. Cassidy, Yu-Hao Chuang, Jeffrey Dunn Vitale

JTRP Technical Reports

This research has sought to demonstrate potential benefits from deploying enhanced vehicle actuation strategies at isolated signalized intersections. The work has exploited microscopic, stochastic simulation to evaluate impacts of enhanced vehicle-actuated (VA) control schemes for an array of operating conditions. Simulated outcomes (i.e. average vehicle delays) generated under the enhanced strategies were compared with outcomes resulting from more “conventional VA control policies. Findings from this work suggest that substantial delay reduction generally occurs by exploiting VA strategies which seek to 1) facilitate the use of the clearance interval by discharging vehicles, 2) shorten the duration of the required clearance interval …

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New Treatment Combinations For Control Of Brush And Vegetation Management Along Indiana Roadsides, D. James Morré Jan 1995

New Treatment Combinations For Control Of Brush And Vegetation Management Along Indiana Roadsides, D. James Morré

JTRP Technical Reports

This report represents results from a project for research to develop and implement new treatment mixtures for control of problem brush, trees and other woody species and herbicide-resistant weeds along Indiana roadsides. An environmentally safe mixture of trichlopyr (Galon Herbicide) and ammonium nitrate for one application control of deciduous roadside vegetation was developed. Also discovered and developed was a new, environmentally safe and effective TR series of additives that enhance the action of the auxin herbicides (trichlopyr, 2,4-D, picloram) for inclusion in both the brush control mixtures and control of milkweed, Canada thistle, bindweed, ground cherry and other perennial, herbicide-resistant …

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A Decision Support System For Real-Time Snow And Ice Control, Hjalmar James Miedema, J. R. Wright Jan 1995

A Decision Support System For Real-Time Snow And Ice Control, Hjalmar James Miedema, J. R. Wright

JTRP Technical Reports

Effective real-time snow and ice control operations require a timely initial call-out. A timely initial call-out is one that mobilizes the workforce slightly prior to the onset of hazardous road conditions. In order to estimate the onset of hazardous road conditions, the snow and ice control decision makers use available physical and meteorological information. New technologies are developed that could provide better information, thereby improving the ability to make timely initial call-outs. A systematic methodology for evaluating the benefit of additional information used in snow and ice control initiation is presented. The purposed methodology compares reduction in the direct and …

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Predicting Traffic Impacts At Two-Lane Highway Work Zones, Michael J. Cassidy, Youngtae Son Jan 1995

Predicting Traffic Impacts At Two-Lane Highway Work Zones, Michael J. Cassidy, Youngtae Son

JTRP Technical Reports

Maintenance or reconstruction activity on a two-lane highway often requires a lane closure. The implementation of “one-way traffic control,” required to maintain traffic flow throughout the work zone, typically produces significant motorist delay. This report describes the adaptation and application of queuing models, originally derived for intersections controlled by vehicle-actuated traffic signals, to estimate delay at two-lane highway work zones. The models estimate expected delay as a function of directional traffic demand rates, work zone physical length and observed traffic measures. Validation efforts using simulation suggest that the models accurately predict the impacts of two-lane highway lane closures.

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Use Of Time Domain Reflectometry For Determination Of Water Content An Density Of Soil, Shafiqul I. Siddiqui, Vincent P. Drnevich Jan 1995

Use Of Time Domain Reflectometry For Determination Of Water Content An Density Of Soil, Shafiqul I. Siddiqui, Vincent P. Drnevich

JTRP Technical Reports

A new method is developed for measuring in-place density and moisture content of soil using the technique of Time Domain Reflectometry (TDR). The method is applicable for construction control of earthworks. The method is extended for measuring moisture content of soil in the laboratory and in the field for various other geotechnical purposes. Laboratory uses include measuring moisture content of soil in compaction molds; field uses include measuring moisture content of soil in Shelby tubes and soil retrieved during drilling and sampling operations. In the course of achieving these goals, this study develops the principles of TDR probe design, test …

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Effects Of Salt And Trace Minerals For Bituminous Pavement Literature Review, Information Gathering, And Research Plan Development, Robert Allan Pittenger, Terry R. West Jan 1995

Effects Of Salt And Trace Minerals For Bituminous Pavement Literature Review, Information Gathering, And Research Plan Development, Robert Allan Pittenger, Terry R. West

JTRP Technical Reports

A review of current literature on the effects of deicing salt and trace minerals, such as sulfate, on aggregate deterioration was conducted. Such deterioration in both Portland cement concrete, and bituminous pavements was reviewed. For Portland cement concrete, it was determined that current research on the effects of moisture and deicing salt on aggregates concrete matrix durability, with little discussion on the effects on aggregates. The effects of trace minerals in deicing salt are also rarely discussed. Pore size distribution, insoluble residue, absorption, and susceptibility to alkali-silica reaction all appear to affect aggregate durability in the presence of moisture of …

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1995 Directory Of Indiana State, County, City And Town Officials Responsible For Road And Street Work, Herpicc Jan 1995

1995 Directory Of Indiana State, County, City And Town Officials Responsible For Road And Street Work, Herpicc

Indiana Local Technical Assistance Program (LTAP) Directory

Contact information for agency officials and employees responsible for Indiana’s local road infrastructure.

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Theoretically Optimal Duty Cycles For Chest And Abdominal Compression During External Cardiopulmonary Resuscitation, Charles F. Babbs, Keir Thelander Jan 1995

Theoretically Optimal Duty Cycles For Chest And Abdominal Compression During External Cardiopulmonary Resuscitation, Charles F. Babbs, Keir Thelander

Weldon School of Biomedical Engineering Faculty Publications

Objective: To use an electronic model of human circulation to compare the hemodynamic effects of different durations of chest compression during external CPR, both with, and without interposed abdominal compression (IAC). Methods: An electrical analog model of human circulation was studied on digital computer workstations using SPICE, a general-purpose circuit simulation program. In the model the heart and blood vessels were represented as resistive-capacitive networks, pressures as voltages, blood flow as electric current, blood inertia as inductance, and cardiac and venous valves as diodes. External pressurization of the heart and great vessels, as would occur in IAC-CPR, was simulated by …

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On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, Shin'ichi Tanaka Jan 1995

On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, Shin'ichi Tanaka

Department of Electrical and Computer Engineering Faculty Publications

A simple one-speed solution to the Boltzmann equation is used to evaluate the mobility and diffusion coefficient for carriers in forward-biased semiconductor barriers. The analysis shows that although the average kinetic energy of carriers remains near thermal equilibrium, the mobility and diffusion coefficient are strongly reduced by the built-in field. Conventional macroscopic transport equations, which treat the carrier mobility and diffusion coefficient as single valued functions of the kinetic energy will improperly treat transport in forward-biased barriers. The results are important for the careful analysis of metal–semiconductor and heterojunction diodes.

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On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, S. I. Tanaka Jan 1995

On The Carrier Mobility In Forward-Biased Semiconductor Barriers, Mark S. Lundstrom, S. I. Tanaka

Department of Electrical and Computer Engineering Faculty Publications

A simple one-speed solution to the Boltzmann equation is used to evaluate the mobility and diffusion coefficient for carriers in forward-biased semiconductor barriers. The analysis shows that although the average kinetic energy of carriers remains near thermal equilibrium, the mobility and diffusion coefficient are strongly reduced by the built-in field. Conventional macroscopic transport equations, which treat the carrier mobility and diffusion coefficient as single valued functions of the kinetic energy will improperly treat transport in forward-biased barriers. The results are important for the careful analysis of metal-semiconductor and heterojunction diodes.© 1995 American Institute of Physics.

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Very Low Resistance Nonalloyed Ohmic Contacts Using Low-Temperature Molecular Beam Epitaxy Of Gaas, M. P. Patkar, T. P. Chin, J. M. Woodall, Mark S. Lundstrom, Michael R. Melloch Jan 1995

Very Low Resistance Nonalloyed Ohmic Contacts Using Low-Temperature Molecular Beam Epitaxy Of Gaas, M. P. Patkar, T. P. Chin, J. M. Woodall, Mark S. Lundstrom, Michael R. Melloch

Department of Electrical and Computer Engineering Faculty Publications

Ex situ nonalloyed ohmic contacts were made to n- and p‐type GaAs using low‐temperature molecular beam epitaxy. For n‐type GaAs, Ag, and Ti/Au nonalloyed contacts displayed specific contact resistitivities of mid 10-7 ohm cm2. For p‐type GaAs, nonalloyed Ti/Au contacts with specific contact resistivities of about 10-7 ohm cm2 were obtained.

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Transition Matrix Approach For Monte Carlo Simulation Of Coupled Electron/Phonon/Photon Dynamics, Muhammad A. Alam, Mark S. Lundstrom Jan 1995

Transition Matrix Approach For Monte Carlo Simulation Of Coupled Electron/Phonon/Photon Dynamics, Muhammad A. Alam, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

A new approach for simulating the dynamics of electrons, phonons, and photons is described. The technique provides a Monte Carlo simulation of particle dynamics without the statistical noise associated with direct Monte Carlo simulation, treats physical phenomena with a wide range of time scales, and has a good computational efficiency. A transition matrix is first precomputed by direct Monte Carlo simulation. Particle populations are then updated at regular time steps by simple matrix multiplication while correcting for nonlinear effects such as carrier–carrier scattering, band filling, hot phonons, etc. The technique is well suited to studies of quantum well laser devices …

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Temperature Dependence Of Minority And Majority Carrier Mobilities In Degenerately Doped Gaas, Michael L. Lovejoy, Michael R. Melloch, Mark S. Lundstrom Jan 1995

Temperature Dependence Of Minority And Majority Carrier Mobilities In Degenerately Doped Gaas, Michael L. Lovejoy, Michael R. Melloch, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

Measured minority and majority carrier mobility temperature dependencies in heavily doped n- and p-GaAs are compared. Majority carrier mobilities in heavily doped GaAs are essentially temperature ~T! independent while minority carrier mobilities exhibit a roughly 1/T dependence. Majority carrier freezeout, which reduces both majority–minority carrier and ionized impurity scattering, is shown not to be responsible for the 1/T minority carrier mobility dependence. The difference in minority and majority carrier mobility T dependencies is explained in terms of the increased degree of degeneracy of majority carriers with decreased temperature, which decreases majority–minority carrier scattering.

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