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Articles 154651 - 154680 of 194019

Full-Text Articles in Engineering

Design Concepts And Process Analysis For Transmuter Fuel Manufacturing: Quarterly Progress Report #1, Jamil M. Renno, Georg F. Mauer Jan 2005

Design Concepts And Process Analysis For Transmuter Fuel Manufacturing: Quarterly Progress Report #1, Jamil M. Renno, Georg F. Mauer

Fuels Campaign (TRP)

A Hot Cell robotic assembly: Pick and place dynamic simulation, including feedback control with Matlab, was developed for dispersion fuel manufacture.

The deployment of remote manufacturing of transmuter fuel is a necessity for the transmutation applications. In the reporting period, a virtual hot cell for the manufacturing of dispersion fuel was designed using MSC.visualNastran©, ProEngineer© and MATLAB©. Atypical events were successfully simulated. Relevant physical quantities arising during such events were monitored as well.


Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems: Quarterly Progress Report (August 2004 – October 2004), Ajit K. Roy Jan 2005

Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems: Quarterly Progress Report (August 2004 – October 2004), Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV), Los Alamos National Laboratory (LANL) and Idaho State University (ISU) is to evaluate the effect of silicon (Si) content on the corrosion behavior and radiation-induced embrittlement of martensitic stainless steels having chemical compositions similar to that of the modified 9Cr-1Mo steel. Recent studies at LANL involving Alloy EP-823 of different Si content have demonstrated that increased Si content in this alloy may enhance the corrosion resistance in molten lead-bismutheutectic (LBE). Since very little data exists in the open literature on the beneficial effect of Si …


Creep Of Granular Ice With And Without Dispersed Particles, Min Song, David M. Cole, Ian Baker Jan 2005

Creep Of Granular Ice With And Without Dispersed Particles, Min Song, David M. Cole, Ian Baker

Dartmouth Scholarship

The effects of silt-sized particles (average diameter of 50 m m) on the compressive creep of polycrystalline ice have been studied at stress levels from 0.1 to 1.45MPa and temperatures of –12 8 C and –10 8 C. Dislocation densities during creep have been estimated using a dislocation-based model of anelasticity. The results indicate that at low concentrations (up to 4wt.% % ), particles increase the minimum creep rate. Power-law behavior with an exponent of 3 was observed for both particle-free ice and ice with 1 wt.% % particles when the stress was >0.3 MPa. In contrast, linear behavior was …


Comprehensive Black Liquor Droplet Combustion Studies, Leong-Teng Ip Jan 2005

Comprehensive Black Liquor Droplet Combustion Studies, Leong-Teng Ip

Theses and Dissertations

Black liquor, a byproduct from pulp production, is burned in a recovery boiler to generate electricity and recover inorganic materials. Black-liquor-droplet combustion is fundamental to understanding and potentially improving recovery boiler performance. This investigation reports comprehensive experimental data collected for a suite of five liquors. All the data were collected with newly-designed laboratory equipment, several aspects of which are unique. Single droplets were suspended on a thermocouple and heated in a furnace. Simultaneous diameter (size and shape), internal and surface temperatures, surface emissivity, and mass were measured under various furnace temperatures and gas compositions. The images recorded by the cameras …


Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements: Quarterly Progress Report (September 01 – November 30, 2004), Ajit K. Roy Jan 2005

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements: Quarterly Progress Report (September 01 – November 30, 2004), Ajit K. Roy

Transmutation Sciences Materials (TRP)

Accomplishments:

● A technical paper titled “Residual Stress Characterization in Structural Materials by Destructive and Nondestructive Techniques” has been accepted for publication in the Journal of Materials Engineering and Performance, ASM International, Ohio.

● The PAS method has been applied to develop calibration curves for line shape parameters (S and T) using unstressed and stressed (different magnitude) tensile specimens of martensitic stainless steels. These curves will enable the determination of residual stresses in plastically-deformed materials once the magnitude of S or T parameter is determined by the PAS technique.

● The tensile and welded specimens have been irradiated by low …


Experimental Verification Of The Aerodynamics Of Stream Thrust Probes, Robert S. Hiers Iii, James R. Sirbaugh, Capt Barrett T. Mccann, Russell M. Cummings, Cadet Laura S. Luft, Cadet Dimitrios P. Grillos Jan 2005

Experimental Verification Of The Aerodynamics Of Stream Thrust Probes, Robert S. Hiers Iii, James R. Sirbaugh, Capt Barrett T. Mccann, Russell M. Cummings, Cadet Laura S. Luft, Cadet Dimitrios P. Grillos

Aerospace Engineering

Determining the local stream thrust (a vector quantity) from a measured pitot pressure (a scalar quantity) requires either knowledge of the flow direction or a probe shape that compensates for flow direction. This compensation ideally would make the measured pressure directly proportional to the component of momentum along the probe axis. The flow angle sensitivity required to resolve this component of momentum was previously determined theoretically. A proposed probe nose shape was analyzed using computational fluid dynamics (CFD) and was found to produce a flow angle sensitivity close to the required sensitivity. In the current work, the proposed nose shape …


Des Turbulence Modeling On The C-130 Comparison Between Computational And Experimental Results, Malcom P. Claus, Scott A. Morton, Russell M. Cummings, Yannick Bury Jan 2005

Des Turbulence Modeling On The C-130 Comparison Between Computational And Experimental Results, Malcom P. Claus, Scott A. Morton, Russell M. Cummings, Yannick Bury

Aerospace Engineering

This paper represents the results from the initial phase of a research program to determine the flow characteristics of the C-130 Hercules transport aircraft. The initial phase of the program consists of evaluation and comparison of the flow-field obtained from flow visualization methods. Specifically CFD (Computational Fluid Dynamics) results are compared with experimental Hot Wire results produced by wind tunnel tests on the C-130 in clean configuration. This paper outlines the results to date and provides a description of further work. The CFD element of this research features the use of Detached Eddy Simulation (DES) in order to extend its …


Computational Aerodynamics Goes To School: A Course In Cfd For Undergraduate Students, Russell M. Cummings, Scott A. Morton Jan 2005

Computational Aerodynamics Goes To School: A Course In Cfd For Undergraduate Students, Russell M. Cummings, Scott A. Morton

Aerospace Engineering

As aerodynamics education has evolved over the past decades, a slow transition from important analytic methods to increasingly powerful computational methods has taken place. While a basic understanding of theoretical aerodynamics should always be included in coursework, the realities of modern design practices make the usefulness of the traditional approach less and less practical. A new undergraduate course in computational aerodynamics has been developed that attempts to give students experience with the modern computational tools of aerodynamics, primarily from an applications perspective. While introducing students to the important computational topics of accuracy and stability, the course stresses the practical tools …


Deformation Of Unstructured Viscous Grids, Denis B. Kholodar, Scott A. Morton, Russell M. Cummings Jan 2005

Deformation Of Unstructured Viscous Grids, Denis B. Kholodar, Scott A. Morton, Russell M. Cummings

Aerospace Engineering

A mesh deformation algorithm for unstructured grids is presented. It is designed for high Reynolds number flow problems. Such grids are employed in aerodynamic and aeroelastic studies of wings or complete aircraft configurations in flows where the viscous effects are important. Given a surface deformation, the method efficiently recalculates new locations of high aspect ratio cells that make up the viscous layers of the grid and then deforms the inviscid part of the grid using an established method based on a torsional spring analogy technique. Results are presented for monitoring the deterioration of the quality of the grid during subsequent …


Single-Layer-Coated Beam Splitters For The Division-Of-Amplitude Photopolarimeter, Rasheed M.A. Azzam, Faisal F. Sudradjat Jan 2005

Single-Layer-Coated Beam Splitters For The Division-Of-Amplitude Photopolarimeter, Rasheed M.A. Azzam, Faisal F. Sudradjat

Electrical Engineering Faculty Publications

A design procedure is presented for a near-optimal, single-layer-coated prism beam splitter that serves as the key optical element of the division-of-amplitude photopolarimeter (DOAP). For given film and substrate refractive indices, the angle of incidence and film thickness are selected such that the ellipsometric differential phase shifts in reflection and transmission Delta_r and Delta_t differ by ±pi/2, and the normalized determinant of the instrument matrix is maximized. The best results are obtained by using high-index films on low-index substrates. This is illustrated by examples of ZnS and GaP films on silica prisms in the visible and Si, Ge, and PbTe …


A Three Dimensional Finite Element Model For Emergency Response, Xiuling Wang, Darrell W. Pepper, Yitung Chen, Sean Hsieh Jan 2005

A Three Dimensional Finite Element Model For Emergency Response, Xiuling Wang, Darrell W. Pepper, Yitung Chen, Sean Hsieh

Mechanical Engineering Faculty Research

No abstract provided.


Robust Control Techniques For State Tracking In The Presence Of Variable Time Delays, Jarrett Goodell, Marc Compere, Miguel Simon, Wilford Smith, Ronnie Wright, Mark Brudnak Jan 2005

Robust Control Techniques For State Tracking In The Presence Of Variable Time Delays, Jarrett Goodell, Marc Compere, Miguel Simon, Wilford Smith, Ronnie Wright, Mark Brudnak

Publications

In this paper, a distributed driver-in-the-Ioop and hardware-in-the-Ioop simulator is described with a driver on a motion simulator at the U.S. Army TARDEC Ground Vehicle Simulation Laboratory (GVSL). Realistic power system response is achieved by linking the driver in the GVSL with a full-sized hybrid electric power system located 2,450 miles away at the TARDEC Power and Energy Systems Integration Laboratory (P&E SIL), which is developed and maintained by Science Applications International Corporation (SAIC). The goal is to close the loop between the GVSL and P&E SIL over the Internet to provide a realistic driving experience in addition to realistic …


Electromagnetically Induced Transparency In Alkali Atoms Integrated On A Semiconductor Chip, Aaron R. Hawkins, Holger Schmidt Jan 2005

Electromagnetically Induced Transparency In Alkali Atoms Integrated On A Semiconductor Chip, Aaron R. Hawkins, Holger Schmidt

Faculty Publications

We analyze the integration of electromagnetically induced transparency in alkali atoms on a semiconductor chip. We propose the use of antiresonant reflecting optical waveguides with hollow cores to realize the necessary waveguiding capability and optical mode areas of a few square micrometers. We derive the scaling laws and limitations for the reduction in group velocity and single-photon phase shifts as a function of waveguide dimension. We show that miniaturization leads to a large enhancement of single-photon cross-phase modulation, despite the presence of additional limitations due to coherence dephasing and waveguide loss.


Dynamic Reconfigurable Machine Tool Controller, Wei Li Jan 2005

Dynamic Reconfigurable Machine Tool Controller, Wei Li

Theses and Dissertations

This dissertation presents a dynamic reconfigurable control strategy based on the Direct Machining And Control (DMAC) research at Brigham Young University. A reconfigurable framework is proposed which will allow a machine tool to be controlled by a variety of applications and control laws. This Reconfigurable Mechanism for Application Control (RMAC) paradigm uses a hierarchical architecture to configure a mechanism into a device driver for direct control by an application like CAD/CAM. The RMAC paradigm is one of a mechanism device driver assigned to each mechanism class or model, and uses only the master model to control the mechanism. The traditional …


Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Iii, Third Quarterly Report, Robert A. Schill Jr., Mohamed Trabia, William Culbreth Jan 2005

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Iii, Third Quarterly Report, Robert A. Schill Jr., Mohamed Trabia, William Culbreth

Transmutation Sciences Materials (TRP)

This quarterly report provides an update to the last phase of the Modeling, Fabrication, and Optimization of Niobium Cavities in the no-cost extension period. Designing the experimental setup of secondary electron emission was well underway in early summer of 2003 when funding was made available for this portion the study. By March 2004, many of the components of the experimental study reached UNLV with some assembly accomplished. The first secondary electron emission (SEE) measurement was made from the surface of a Faraday cup in September 2004. In December of 2005, the software for the particle positioning detector was finally up …


Applying Alternative Technologies To Cafos: A Case Study, Richard K. Koelsch, Carol Balvanz, John George, Dan Meyer, John A. Nienaber, Gene Tinker Jan 2005

Applying Alternative Technologies To Cafos: A Case Study, Richard K. Koelsch, Carol Balvanz, John George, Dan Meyer, John A. Nienaber, Gene Tinker

Department of Biological Systems Engineering: Conference Presentations and White Papers

The US EPA National Pollution Discharge Elimination System permit program has regulated open lot livestock production systems since the 1970’s, historically requiring collection, storage, and land application of runoff. Under the new Concentrated Animal Feeding Operation (CAFO) regulations, the effluent limitation guidelines (ELG) offer the option of Voluntary Alternative Performance Standards for beef and dairy. This potentially allows runoff management options such as vegetative treatment systems (VTS) that may perform equal to or better than our baseline system while maintaining a challenging standard for application of alternative technologies.

To facilitate application of VTS, the Iowa Cattlemen’s Association (ICA) and Iowa …


Using Ems’S To Improve Compliance On Livestock And Poultry Operations, L. Mark Risse, Richard K. Koelsch, W. L. Bland, Elizabeth A. Bird, Thomas M. Bass Jan 2005

Using Ems’S To Improve Compliance On Livestock And Poultry Operations, L. Mark Risse, Richard K. Koelsch, W. L. Bland, Elizabeth A. Bird, Thomas M. Bass

Department of Biological Systems Engineering: Conference Presentations and White Papers

Across the United States and abroad, innovative producers, processors, trade organizations and others in the agricultural sector are exploring the promise of Environmental Management Systems (EMS) to improve their environmental and business performance. An Environmental Management System or EMS helps farmers develop their own, personal strategies for reducing environmental risk on their operations by integrating environmental management considerations into production management decisions. It is a voluntary, flexible approach and is based on a producer's own sense of how best to manage an operation.

Partnerships for Livestock Environmental Management Systems is a 4-year project to explore the potential of livestock Environmental …


Engineering Tools For Variable Stiffness Vibration Suppression And Isolation, Michael F. Winthrop Jan 2005

Engineering Tools For Variable Stiffness Vibration Suppression And Isolation, Michael F. Winthrop

Theses and Dissertations

With the advent of smart materials, the concept of semi-active control or dynamic control of stiffness and/or damping for vibration control of structures has become practical and has seen limited use. Semi-active control has advantages over active and passive control methods, since it provides almost as much capability as active control while requiring much less power. Its main disadvantage is its inherent nonlinearity, greatly complicating engineering design. The purpose of this research is to extend semi-active control vibration isolation tools and methods considering space launch and on-orbit systems.


Sub-Surface Corrosion Research On Rock Bolt System, Perforated Ss Sheets And Steel Sets For The Yucca Mountain Repository — Quarterly Technical Report No. 2, Dhanesh Chandra Jan 2005

Sub-Surface Corrosion Research On Rock Bolt System, Perforated Ss Sheets And Steel Sets For The Yucca Mountain Repository — Quarterly Technical Report No. 2, Dhanesh Chandra

Publications (YM)

This report encompasses the work done for second quarter in accordance to cooperative agreement of UCCSN for the Task 019 “Subsurface Corrosion Research on Rock Bolt System, Perforated SS Sheets and Steel Sets for the Yucca Mountain Repository”, the objective of which was proposed earlier, to conduct corrosion research and predict the durability of rock-bolts and other underground metallic roof supports. We have recently started working on oxidation tests using Thermogravimetric Analyzer, stress corrosion cracking/hydrogen embrittlement studies on rock bolts, other support materials including bench mark materials.

In this quarterly report we will discuss “Dry” oxidation of steels and other …


Performance Of Concrete Bridge Deck Joints, Lik Hang Yuen Jan 2005

Performance Of Concrete Bridge Deck Joints, Lik Hang Yuen

Theses and Dissertations

The purpose of this research was to identify the types of joints available for use on concrete bridge decks and to investigate the performance characteristics of each type, including primary functions and movement ranges. Eleven reports on joint performance published by state departments of transportation and universities nationwide were analyzed in order to obtain information on joint performance problems typically encountered by state transportation agencies. In addition, test methods and specifications provided by the American Society for Testing and Materials (ASTM) were reviewed for application by bridge engineers to ensure the adequacy of deck joints.

The research indicates that compression …


Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander Jan 2005

Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander

Papers in Biotechnology

Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1 kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the Aα,Bβ and γ fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 μg/ml, with total secretion of subunits approaching 700 μ g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. …


Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander Jan 2005

Secretion Of Recombinant Human Fibrinogen By The Murine Mammary Gland, William H. Velander

Papers in Biotechnology

Transgenic animals secreting individual chains and assembled fibrinogen were produced to evaluate the capacity of the mammary gland for maximizing assembly, glycosylation and secretion of recombinant human fibrinogen (rhfib). Transgenes were constructed from the 4.1 kbp murine Whey Acidic Protein promoter (mWAP) and the three cDNAs coding for the Aα,Bβ and γ fibrinogen chains. Transgenic mice secreted fully assembled fibrinogen into milk at concentrations between 10 and 200 μg/ml, with total secretion of subunits approaching 700 μ g/ml in milk. Partially purified fibrinogen was shown to form a visible and stable clot after treatment with human thrombin and factor XIII. …


Elevated Temperature Deformation Behavior Of Nanostructured Al-Ni-Gd-Fe Alloys, X. L. Shi, Rajiv S. Mishra, T. J. Watson Jan 2005

Elevated Temperature Deformation Behavior Of Nanostructured Al-Ni-Gd-Fe Alloys, X. L. Shi, Rajiv S. Mishra, T. J. Watson

Materials Science and Engineering Faculty Research & Creative Works

The elevated temperature deformation behavior of nanostructured Al89Ni3Gd7Fe1 alloy was characterized. Tensile strength was 760 MPa at 373 K. Ductility of the alloy increases with increasing strain rate at 573 K. At high temperatures (623-673 K), the operative deformation mechanism is dislocation-climb controlled.


Supplement 2004 To The North American Specification For The Design Of Cold-Formed Steel Structural Members 2001 Edition, American Iron And Steel Institute Jan 2005

Supplement 2004 To The North American Specification For The Design Of Cold-Formed Steel Structural Members 2001 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by a joint effort of the American Iron and Steel Institute Committee on Specifications, the Canadian Standards Association Technical Committee on Cold Formed Steel Structural Members (S136), and Camara Nacional de la Industria del Hierro y del Acero (CANACERO) in Mexico. The organizations and the Committees have made a diligent effort to present accurate, reliable, and useful information on cold-formed steel design. The Committees acknowledge and are grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included …


Supplement 2004 To The North American Specification For The Design Of Cold-Formed Steel Structural Members, American Iron And Steel Institute Jan 2005

Supplement 2004 To The North American Specification For The Design Of Cold-Formed Steel Structural Members, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by a joint effort of the American Iron and Steel Institute Committee on Specifications, the Canadian Standards Association Technical Committee on Cold Formed Steel Structural Members (S136), and Camara Nacional de la Industria del Hierro y del Acero (CANACERO) in Mexico. The organizations and the Committees have made a diligent effort to present accurate, reliable, and useful information on cold-formed steel design. The Committees acknowledge and are grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included …


Distortional Buckling Of Cold-Formed Steel Members In Bending, Cheng Yu, Benjamin W. Schafer Jan 2005

Distortional Buckling Of Cold-Formed Steel Members In Bending, Cheng Yu, Benjamin W. Schafer

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

Laterally braced cold-formed steel beams generally fail due to local and/or distortional buckling in combination with yielding. For many cold-formed steel (CFS) studs, joists, purlins, or girts, distortional buckling may be the predominant buckling mode. However, distortional buckling of CFS beams remains a largely unaddressed problem in the current North American Specification for the Design of Cold-Formed Steel Structural Members (NAS). Further, adequate experimental data on unrestricted distortional buckling in bending is unavailable. Therefore, two series of bending tests on industry standard CFS C and Z-sections were performed and presented in this dissertation. The testing setup was carefully designed in …


Modeling Natural, Organic Matter In An Unfiltered Surface Water Supply, Daniel R. Buttrick Jan 2005

Modeling Natural, Organic Matter In An Unfiltered Surface Water Supply, Daniel R. Buttrick

Environmental & Water Resources Engineering Masters Projects

Wachusett Reservoir, located in central Massachusetts, supplies water to the Boston, Massachusetts metropolitan area. The reservoir receives water from a watershed of 117 square miles, as well as water transferred from the Quabbin Reservoir to the west. Quabbin Reservoir water generally has lower levels of most water quality constituents than water received from the Wachusett Reservoir watershed. The Massachusetts Department of Conservation and Recreation (DCR) manages the watershed and monitors tributary and in-reservoir water quality, while the Massachusetts Water Resources Authority (MWRA) is responsible for treatment and distribution. CE QUAL W2 is a two dimensional, laterally averaged water quantity and …


Genome-Wide Requirements For Resistance To Functionally Distinct Dna-Damaging Agents, Patrick Flaherty Jan 2005

Genome-Wide Requirements For Resistance To Functionally Distinct Dna-Damaging Agents, Patrick Flaherty

Mathematics and Statistics Department Faculty Publication Series

The mechanistic and therapeutic differences in the cellular response to DNA-damaging compounds are not completely understood, despite intense study. To expand our knowledge of DNA damage, we assayed the effects of 12 closely related DNA-damaging agents on the complete pool of ;4,700 barcoded homozygous deletion strains of Saccharomyces cerevisiae. In our protocol, deletion strains are pooled together and grown competitively in the presence of compound. Relative strain sensitivity is determined by hybridization of PCR-amplified barcodes to an oligonucleotide array carrying the barcode complements. These screens identified genes in well-characterized DNAdamage-response pathways as well as genes whose role in the DNA-damage …


Onset And Ornament Detection And Music Transcription For Monophonic Traditional Irish Music, Aileen Kelleher Jan 2005

Onset And Ornament Detection And Music Transcription For Monophonic Traditional Irish Music, Aileen Kelleher

Masters

To date, much has been... This abstract will be longer in due course!


Gain-Bandwidth Product Optimization Of Heterostructure Avalanche Photodiodes, Oh-Hyun Kwon, Majeed M. Hayat, Joe C. Campbell, Bahaa E.A. Saleh, Malvin Carl Teich Jan 2005

Gain-Bandwidth Product Optimization Of Heterostructure Avalanche Photodiodes, Oh-Hyun Kwon, Majeed M. Hayat, Joe C. Campbell, Bahaa E.A. Saleh, Malvin Carl Teich

Electrical and Computer Engineering Faculty Research and Publications

A generalized history-dependent recurrence theory for the time-response analysis is derived for avalanche photodiodes with multilayer, heterojunction multiplication regions. The heterojunction multiplication region considered consists of two layers: a high-bandgap Al/sub 0.6/Ga/sub 0.4/As energy-buildup layer, which serves to heat up the primary electrons, and a GaAs layer, which serves as the primary avalanching layer. The model is used to optimize the gain-bandwidth product (GBP) by appropriate selection of the width of the energy-buildup layer for a given width of the avalanching layer. The enhanced GBP is a direct consequence of the heating of primary electrons in the energy-buildup layer, which …