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Full-Text Articles in Engineering

Center For Computer And Information Sciences Application Package 1990, Nova Southeastern University Jan 1990

Center For Computer And Information Sciences Application Package 1990, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.


A Simulation Testbed For Image Compression Algorithms, Andrew Francis Laine Jan 1990

A Simulation Testbed For Image Compression Algorithms, Andrew Francis Laine

All Computer Science and Engineering Research

This paper presents an overview of the design and development of a real-time (30 frames/sec) simulation testbed for evaluating and comparing image compression algorithms. The system was motivated by the need to visualize the performance of a novel compression algorithm when operating on moving pictures originating from "live" video sources. The simulation utilities are designed to exploit the parallelism of a Pixar Image Computer and high-throughput of a parallel disk assembly. The design of two key utilities are discussed: (1) A program to format precomputed four channel (RGBA) 256 X 256 color frames onto a parallel disk assembly. (2) A …


Thermal Dynamic Problems Of Reinforced Composite Cylinders, Victor Birman Jan 1990

Thermal Dynamic Problems Of Reinforced Composite Cylinders, Victor Birman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Thermal dynamic problems of circular cylindrical composite shells reinforced in the axial and circumferential directions and subject to variations of temperature are considered. Nonlinear governing equations are formulated based on the extension of Donnell shell theory. These equations are used to determine the response of geometrically nonlinear and linear shells to a thermal loading represented by the Heaviside step function (thermal shock). The solution of the nonlinear problem obtained by the assumption that displacements are single-term functions of coordinates is discussed. The analysis of the linear problem illustrates different types of response to thermal shock. The condition of thermally induced …


Conductivity Of N-Dimensional Composites Containing Hyperspherical Inclusion, Ashok S. Sangani Jan 1990

Conductivity Of N-Dimensional Composites Containing Hyperspherical Inclusion, Ashok S. Sangani

Biomedical and Chemical Engineering - All Scholarship

A problem of determining the macroscopic or effective thermal conductivity of an N-dimensional composite medium containing N-dimensional nonoverlapping hyperspherical inclusions is considered. Since the macroscopic conductivity is expected to become less sensitive to the detailed spatial distribution of the inclusions for N ≥ 4, only the special case of periodic arrangement of the inclusions is considered. An expression for the macroscopic conductivity correct to O(χ3N + 8), χ being the ratio of "diameter" of the inclusions to the spacing between them, is derived and the numerical results for the conductivity are presented as a function of χ and N for …


Comments On The Papers By Kê And Su, Hollis P. Leighly Jan 1990

Comments On The Papers By Kê And Su, Hollis P. Leighly

Materials Science and Engineering Faculty Research & Creative Works

No abstract provided.


Mass-Transfer Measurements Of Copper Deposition In A Fluosilicate Electrolyte, D. Uceda, Thomas J. O'Keefe, E. Cole Jan 1990

Mass-Transfer Measurements Of Copper Deposition In A Fluosilicate Electrolyte, D. Uceda, Thomas J. O'Keefe, E. Cole

Materials Science and Engineering Faculty Research & Creative Works

The electrodeposition of copper from a fluosilicate electrolyte has been investigated by electrochemical techniques, x-ray diffraction, and scanning electron microscopy. The diffusion coefficient of cupric ion in a fluosilicate solution has been determined with the aid of a rotating disk electrode using the mixed control Levich equation. Gold (Au+3) was used as a tracer to evaluate the mass transport properties of the system. The polarization behavior of the electrolyte was measured in the presence and absence of gas sparging on a vertical stationary electrode to study the effect of the mass transport contribution. Sound copper deposits were obtained …


Production Of Thin Copper Foils On Microporous Titanium Oxide Substrates, J. L. Delplancke, M. Sun, Thomas J. O'Keefe, R. Winand Jan 1990

Production Of Thin Copper Foils On Microporous Titanium Oxide Substrates, J. L. Delplancke, M. Sun, Thomas J. O'Keefe, R. Winand

Materials Science and Engineering Faculty Research & Creative Works

This study deals with the electrochemical production of thin (35 μm) copper films on anodized titanium substrates. The formation of a microporous oxide layer on the titanium electrodes greatly enhances the surface density of copper nuclei during a potentiostatic experiment so that a complete coverage of the cathode surfaces may be obtained after short term (20 s) polarization. Moreover, the oxide film may act as a parting agent and the copper films may be easily stripped from their substrates. The higher the pore density of the oxide film, the higher the surface density of nuclei and the easier the foil's …


Combined Solar And Internal Load Effects On Selection Of Heat Reclaim-Economizer Hvac Systems, Harry J. Sauer, Ronald Hunter Howell, Zijie Wang Jan 1990

Combined Solar And Internal Load Effects On Selection Of Heat Reclaim-Economizer Hvac Systems, Harry J. Sauer, Ronald Hunter Howell, Zijie Wang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The concern for energy conservation has led to the development and use of heat recovery systems which reclaim the building internal heat before it is discarded in the exhaust air. On the other hand, economizer cycles have been widely used for many years in a variety of types of HVAC systems. Economizer cycles are widely accepted as a means to reduce operating time for chilling equipment when cool outside air is available. It has been suggested that heat reclaim systems should not be used in conjunction with an HVAC system which incorporates an economizer cycle because the economizer operation would …


Effect Of Viscoplastic Flow Rules On The Initiation And Growth Of Shear Bands At High Strain Rates, R. C. Batra, Chang-Soo Kim Jan 1990

Effect Of Viscoplastic Flow Rules On The Initiation And Growth Of Shear Bands At High Strain Rates, R. C. Batra, Chang-Soo Kim

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Marchand and Duffy have reported detailed measurements of the temperature and strain as a shear band develops in a HY-100 steel. Assuming their torsional tests in thin-wall tubes can be adequately modeled by a viscoplastic block undergoing overall adiabatic simple shearing deformations, we investigate the effect of modeling the viscoplastic response of the material by a.power law, and flow rules proposed by Litonski, Bodner and Partom, and Johnson and Cook. Each of these flow rules is first calibrated by using the test data at a nominal strain-rate of 3300 s-1. Then predictions from the use of these flow rules at …


Design Of Robust Controllers For Gas Turbine Engines, David E. Moellenhoff, Vittal S. Rao, Charles A. Skarvan Jan 1990

Design Of Robust Controllers For Gas Turbine Engines, David E. Moellenhoff, Vittal S. Rao, Charles A. Skarvan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes robust controller design methodologies for gas turbine engines. A linear state variable model for the engine is derived using partial derivatives. The Linear Quadratic Gaussian with Loop Transfer Recovery (LQG/LTR) and the Parameter Robust Linear Quadratic Gaussian (PRLQG) robust controller design methodologies have been used to design a controller for gas turbine engines. A new method is proposed by combining the features of LQG/LTR and PRLQG methods and yields good robustness properties with respect to both unstructured uncertainties in the frequency domain and structured parameter variations in the time domain. The new procedure is illustrated with the …


Reduced Order Modeling Methods For Turret-Gun System, Vittal S. Rao, Norman P. Coleman Jan 1990

Reduced Order Modeling Methods For Turret-Gun System, Vittal S. Rao, Norman P. Coleman

Electrical and Computer Engineering Faculty Research & Creative Works

Reduced-order modeling techniques are used to design lower order robust controllers for a turret-gun system. The balance-truncation, Routh approximation, and L. Litz's (1980) modal techniques are used to derive the models. A critical comparison of the time and frequency response characteristics of the original and reduced order models is made. The spillover problem associated with a reduced-order model is investigated.


Evaluation Of The Cost-Effectiveness Of Pavement Surface Maintenance Activities, Ibrahim Moussa Mouaket, Abdullah Al-Mansour, Kumares C. Sinha Jan 1990

Evaluation Of The Cost-Effectiveness Of Pavement Surface Maintenance Activities, Ibrahim Moussa Mouaket, Abdullah Al-Mansour, Kumares C. Sinha

JTRP Technical Reports

This study covers pavement surface maintenance on three surface types: rigid, flexible and composite (asphalt overlay on rigid pavement). It addresses 3 main issues as follows: 1) Do routine maintenance activities make a difference in terms of pavement serviceability? If yes, how much? 2) Are chip and sand seal coating cost-effective? What is their optimal timing? 3) What management criteria should be used as a guide to make seal coating decisions on specific roadways? In resolving Issue #1, a stratified 2-stage sample of observational data was used in a statistical before/after comparison. SAS-General Linear Model was used due to its …


Test 1637: White 80 Diesel 18-Speed, Nebraska Tractor Test Lab Jan 1990

Test 1637: White 80 Diesel 18-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Test 1638: Belarus 420a And 400a Diesel 11-Speed, Nebraska Tractor Test Lab Jan 1990

Test 1638: Belarus 420a And 400a Diesel 11-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …


Nebraska Summary: S076 Case-Ih 5130, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S076 Case-Ih 5130, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S073 Massey Ferguson 362, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S073 Massey Ferguson 362, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S118 Ford Versatile 9030, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S118 Ford Versatile 9030, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S124 Massey Ferguson 3660, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S124 Massey Ferguson 3660, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S119 Ford Versatile 846, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S119 Ford Versatile 846, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Nebraska Summary: S123 Massey Ferguson 3140, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S123 Massey Ferguson 3140, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …


Use Of Energy In Data-Track Association And State Estimation In Multitarget-Multisensor Problems, S. N. Balakrishnan, H. Park Jan 1990

Use Of Energy In Data-Track Association And State Estimation In Multitarget-Multisensor Problems, S. N. Balakrishnan, H. Park

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A coarse test and a fine test have been formulated for use in multiple sensor-multiple target data-track association. Various forms of energies are used in these tests to pick the proper data to be associated with any target. Numerical experiments which involve the use of a decentralized Kalman filter scheme are presented. The experiments show the effectiveness of the two tests


A Complete Model Characterization Of Brushless Dc Motors, N. Hemati, Ming-Chuan Leu Jan 1990

A Complete Model Characterization Of Brushless Dc Motors, N. Hemati, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The modeling problem associated with brushless DC motors (BLDCMs) with nonuniform air gaps which operate in a range where magnetic saturation may exist is addressed. The mathematical model, includes the effects of reluctance variations and magnetic saturation to guarantee proper modeling of the system. An experimental procedure is developed and implemented in a laboratory environment to identify the electromagnetic characteristics of a BLDCM in the presence of magnetic saturation. It is demonstrated that the modeling problem associated with this class of BLDCM can be formulated in terms of mathematically modeling a set of multidimensional surfaces corresponding to the electromagnetic torque …


Monitored Residential Space Cooling Electricity Consumption In A Hot-Humid Climate: Magnitude, Variation And Reductionfrom Retrofits, Florida Solar Energy Center, Danny Parker Jan 1990

Monitored Residential Space Cooling Electricity Consumption In A Hot-Humid Climate: Magnitude, Variation And Reductionfrom Retrofits, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

There are few end-use studies that report monitored space cooling energy consumption for residential buildings in hot-humid climates. This paper reports data from 25 occupied single-family houses in Palm Beach County, Florida (Messenger et.al. 1982). The houses were first monitored for one year in 1981 to establish their space cooling consumption. After the first year of monitoring they received a battery of retrofits predicted to reduce household energy use. Incorporated measures included conversion to high-efficiency air conditioners or heat pumps, added ceiling insulation, window films, awnings, zoned conditioning systems and ceiling fans. The houses were then monitored for an additional …


The Parallel Implementation Of The Waveform Relaxation Method For Transient Stability Simulations, Marija D. Ilić, Mariesa Crow Jan 1990

The Parallel Implementation Of The Waveform Relaxation Method For Transient Stability Simulations, Marija D. Ilić, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the authors extend the results of their earlier paper on waveform relamtion (WR), which is a parallel algorithm for transient stability analysis. The WR algorithm is extended to a structure-preserving power system model in which the loads are retained. This results in a system of differential/ algebraic equations (DAEs). Power systems exhibit several unique dynamic properties which may be exploited in an advantageous manner by the WR algorithm. This leads to a greater computational efficiency than most other direct methods of simulation. This paper presents several theoretical results as well as computational results on parallel implementation.


An Electronic Surveillance And Control System For Traffic Management On The Borman Expressway, Part I : Executive Summary, Michael J. Cassidy, Kumares C. Sinha Jan 1990

An Electronic Surveillance And Control System For Traffic Management On The Borman Expressway, Part I : Executive Summary, Michael J. Cassidy, Kumares C. Sinha

JTRP Technical Reports

No abstract provided.


Engineering Soils Map Of Blackford County, Indiana, Andrew Garrigus Jan 1990

Engineering Soils Map Of Blackford County, Indiana, Andrew Garrigus

JTRP Technical Reports

This report entitled "Engineering Soils Map of Blackford County, Indiana," completes a portion of the long-term project concerned with the development of county engineering soils maps of the 92 counties in the state of Indiana. This is the 86th report of the series. The report was prepared by Andrew Garrigus, Research Assistant, Joint Highway Research Project, under my direction. The soils mapping of Blackford County was done primarily by the analysis of landforms and associated parent materials as portrayed on stereoscopic aerial photographs. Extensive additional information on the soils was obtained from the soil survey and publications of the Soil …


A Simple Model For A Zinc/Bromine Flow Cell And Associated Storage Tanks, G. D. Simpson, Ralph E. White Jan 1990

A Simple Model For A Zinc/Bromine Flow Cell And Associated Storage Tanks, G. D. Simpson, Ralph E. White

Faculty Publications

A simple model for a parallel plate, zinc/bromine flow cell and associated storage tanks is presented and used to make time-dependent predictions for various quantities in the system. The model is based on a previously published algebraic model of the cell at steady-state and time-dependent, first-order differential equations for the storage tanks. The Butler-Volmer equation is used for the electrochemical reactions, and the homogeneous reaction between bromine and bromide is included. The model predictions indicate that the charging operation of a zinc/bromine battery can be significantly improved by using a storage tank with a larger residence time for the bromine …


Mathematical Modeling Of An H2s Removal Electrolyzer, Z. Mao, P. Adanuvor, Ralph E. White Jan 1990

Mathematical Modeling Of An H2s Removal Electrolyzer, Z. Mao, P. Adanuvor, Ralph E. White

Faculty Publications

A mathematical model is presented for a high temperature H2S electrolyzer. It is shown that the maximum current in this type of a cell is determined entirely by the transport rate of sulfide ions through the separator. It is suggested that this model could be used to determine the feasibility of various designs for this electrolyzer.


Electrochemical Behavior Of Graphite And Ni-Cr Electrodes In Sodium Polysulfide In The Absence And Presence Of Hydrogen Sulfide, Z. Mao, Ralph E. White, B. Dandapani, A. Anani, S. Srinivasan, A. J. Appleby Jan 1990

Electrochemical Behavior Of Graphite And Ni-Cr Electrodes In Sodium Polysulfide In The Absence And Presence Of Hydrogen Sulfide, Z. Mao, Ralph E. White, B. Dandapani, A. Anani, S. Srinivasan, A. J. Appleby

Faculty Publications

The electrochemical behavior of graphite and Ni-Cr electrodes in sodium tetrasulfide melt has been investigated using voltammetric, chronoamperometric, and chronopotentiometric techniques in the presence and absence of hydrogen sulfide. Two continuous phases, namely, Na2S2 and Na2S, are apparently formed at different potentials during the cathodic polarization. The blocking effect by these layers was much less significant on the Ni-Cr electrode than on graphite. The presence of H2S did not appear to influence the electrode reactions, but it significantly reduced the rate of formation of the continuous phases (Na2S2 or Na …


A Computer Simulation Of The Oxygen Reduction Reaction In Carbonate Melts, P. K. Adanuvor, Ralph E. White, A. J. Appleby Jan 1990

A Computer Simulation Of The Oxygen Reduction Reaction In Carbonate Melts, P. K. Adanuvor, Ralph E. White, A. J. Appleby

Faculty Publications

A computer simulation of the oxygen reduction reaction in various carbonate melts has been carried out under steady-state conditions on the basis of a proposed kinetic model which takes into consideration the autocatalytic reaction involving oxygen and other reducible oxygen species in the melt, and the neutralization of oxide ions by dissolved carbon dioxide. A simulation of the presence of (physically) dissolved oxygen, in the diffusion layer region of the melt, corresponding to the possible situation in porous electrodes, causes a significant enhancement in the polarization curves, particularly in the mass-transfer control region. On the other hand, high levels of …