Engineering Commons^™

Freeway Control Via Ramp Metering: Development Of A Basic Building Block For An On-Ramp, Discrete, Stochastic, Mesoscopic, Simulation Model Within A Contextual Systems Approach, Mohamed Yaser Alkadri

Dissertations and Theses

One of the most effective measures of congestion control on freeways has been ramp metering, where vehicle entry to the freeway is regulated by traffic signals (meters). Meters are run with calibrated influx rates to prevent highway saturation. However, recent observations of some metering sites in San Diego, CA indicate that metering, during peak hour demand, is helping freeway flow while sometimes creating considerable traffic back-ups on local streets, transferring congestion problems from the freeway to intersections. Metering problems stem largely from the difficulty of designing an integrated, dynamic metering scheme that responds not only to changing freeway conditions but …

Properties Of Ruthenium Oxide Coatings, Roger M. Hawk, Kamesh V. Gadepally, David N. Patangia

Journal of the Arkansas Academy of Science

Ruthenium oxide coatings have been deposited on titanium substrates using a flood coating process. These films were heat treated for varying times and temperatures. The resulting films subsequently were characterized by performing resistivity and SEM analyses. Resistivity of the ruthenium oxide coating was found to be extremely dependent upon the firing temperature. Effect of the process conditions and formulations of the coatings on the morphology with respect to their electrical characteristics is presented. Capacitors were fabricated using plates coated with ruthenium oxide coatings. Capacitance versus heat treatment temperatures are discussed and at one firing temperature (480'C), the capacitance was 50 …

Simple Synchronous Detector For Spectroscopic Studies, Mokhtar Mofidi, M. Keith Hudson, Reagan Cole, James D. Wilson

Journal of the Arkansas Academy of Science

Lock-in-amplifiers are used in many applications for signal processing and offer the ability to discriminate high levels of noise. While these instruments are very powerful and offer many features, they are not portable and are expensive. An economical and easy to use alternative circuit is presented which incorporates pre-amplification, reference, and synchronous detection on one circuit board. The design can be used in laboratory or process control situations where its small size and low cost are advantageous. The circuit was successfully applied to moderate and high level signals as seen in flame infrared emission detection and in a portable radiometer …

Electric Field Induced Emission As A Diagnostic Tool For Measurement Of Local Electric Field Strengths, A. N. Dharamsi, K. H. Schoenbach

Bioelectrics Publications

The phenomenon of electric field induced (EFI) emission is examined in several diatomic and polyatomic molecules. The possibility of using this phenomenon as a diagnostic tool to measure, nonintrusively, the strength and direction of local electric fields in plasmas is discussed. An estimate of the EFI signal emitted in a typical application plasma is given. This yields a lower bound on the detector sensitivity necessary to exploit EFI emission in practical applications. It is concluded that, at present, the EFI signal could be measured by some very sensitive infrared detection schemes available. Current progress in infrared detector technology, if maintained, …

Reduced Order H∞ Controller Design, Seng Chu Chow

Masters Theses

"The problem formulation and the development of the H_∞ optimal control theory are reviewed. Various H_∞ robust controller design techniques, including both state and output feedback cases, together with a brief comparison and some remarks on these methodologies arc presented. Also included are a review of the controller order reduction alternatives and various balanced truncation model reduction methods.

A new model reduction technique with reduced error bound is proposed. This proposed technique introduces a new parameter which can be used to select the spectral norm of the model reduction error at low and high frequency ranges according to …

Coordinated Strategic Planning Of Hydroelectric Energy Usage Using Stochastic Dynamic Programming With Decoupled Production Cost Simulation, Duane David Highley

Masters Theses

"The method of Stochastic Dynamic Programming is applied to the problem of Long-term hydrothermal coordination for a five-reservoir system in the Midwest. The model that has been developed will optimize the monthly reservoir elevations to produce the lowest expected energy production cost. The production cost calculations are decoupled from the Dynamic Programming loop, resulting in shorter execution times. Constraints are included for maximum and minimum reservoir elevations, maximum monthly reservoir rise and drop, and maximum and minimum monthly energy production. These constraints help to reduce the state space and shorten execution time. An additional constraint is modeled to control the …

Toward The Development Of Decision Support Tools To Manage The Catis Project Life Cycle, Steven Wayne Mccrary

Doctoral Dissertations

"The American Public Works Administration (1987) states that communities' infrastructures are in need of repair and better management and recommends CATIS (Computer-Assisted Terraspatial Information Systems) as an excellent tool to assist in that endeavor. Small communities have several voids that CATIS technology can fill. This research reports on a life-cycle approach to CATIS adoption that will help small communities to better manage their infrastructure.

It is important for small communities to become aware of the types of systems available and what each system can do. This study presents a straightforward, understandable discussion of CATIS technologies, features, and applications. Justifying the …

Observation Of The Visible Absorption Spectrum Of H2o+, Biswajit Das, John W. Farley

Electrical & Computer Engineering Faculty Research

The Ã ² Ã₁–X̃ ² B̃₁ system of H₂O⁺ has been observed, using laser absorption spectroscopy in a velocity‐modulated discharge. A total of 78 transitions between 14 794 and 15 475 cm⁻¹ have been observed with an uncertainty (1 SD) of 0.02 cm⁻¹, including 76 transitions in the (0,7,0)–(0,0,0) band and 2 in the (0,8,0)–(0,0,0) band. This species is important for cometary astronomy, and intriguing for molecular physics because of its prominent Renner–Teller interaction. Careful measurements were made of the relative intensities of the absorption lines, …

In-Situ Film Thickness Measurements For Real-Time Monitoring And Control Of Advanced Photoresist Track Coating Systems, Richard N. Savage, Thomas E. Metz, Horace O. Simmons

Materials Engineering

This paper explores the methodologies of real-time measurement of photoresist film thickness on silicon wafers using multi-wavelength reflection interferometry. Reflected light from the wafer's surface, containing the interference profile, is collected in-situ via a fiber optic cable and film thickness is determined in real-time via a pattern recognition algorithm. The instrumentation used to make this measurement and its application toward optimizing track performance during spin-coating and back are discussed. Data demonstrating basic thickness versus spin-time and thickness versus bake-time profiles acquired on-line without process disruption are presented along with its utilization toward minimizing process set-up and machine qualification. Moreover, the …

The Production Data-Based Similarity Coefficient Versus Jaccard's Similarity Coefficient, Hamid Seifoddini, Manocher Djassemi

Industrial Technology and Packaging

This paper compares the performance of Jaccard's similarity coefficient with the production data-based similarity coefficient. A number of machine-component charts taken from the literature or randomly generated are used to form machine-component groups. Then, the sum of intercellular and intracellular material handling costs for each machine-component group is calculated and used as a basis for performance evaluation of the two similarity coefficients.

High Heat Flux Cooling For Spacecraft Electronics, Louis C. Chow, John E. Leland

Office for Research Publications and Presentations

An experimental investigation of flow boiling in a curved channel has been performed to ascertain its value in electronics cooling applications. Results have been obtained for flow velocities of 1 to 5 m/s and subcooling of 0.5 to 40 K. These results were compared to those of straight channel under identical velocity and subcooling conditions. The critical heat flux of the curved channel was found to be greater than that of the straight channel. In some cases the increase was found to be marginal, however. An unexplained temperature shift in the nucleate boiling regime was experienced during some experiments. Because …

Self-Pulsation Operating Regime For The Absorber Of A Twin Section Laser Diode, Gerald Farrell, P. Phelan, Joe Hegarty

Articles

The voltage-current characteristic of the absorber of a twin section laser diode is investigated as a function of the gain section current. For self pulsation to occur the absorber must be operated within a specific region of the voltage-current characteristics. This region only exists for absorber voltage current characteristics which contain an S-shaped negative resistance.

Shadow Casting Phenomena At Newgrange, Frank Prendergast

Articles

A digital model of the Newgrange passage tomb and surrounding ring of monoliths known as the Great Circle is used to investigate sunrise shadow casting phenomena at the monument. Diurnal variation in shadow directions and lengths are analysed for their potential use in the Bronze Age to indicate the passage of seasonal time. Computer-aided simulations are developed from a photogrammetric survey to accurately show how three of the largest monoliths, located closest to the tomb entrance and archaeologically coded GC1, GC-1 and GC-2, cast their shadows onto the vertical face of the entrance kerbstone, coded K1. The phenomena occur at …

Identification Of Tetragonal And Cubic Structures Of Zirconia Using Synchrotron X-Radiation Source, Ram Srinivasan, Robert J. De Angelis, Gene Ice, Burtron H. Davis

Department of Mechanical and Materials Engineering: Faculty Publications

X-ray diffraction from a synchrotron source was employed in an attempt to identify the crystal structures in zirconia ceramics produced by the sol-gel method. The particles of chemically precipitated zirconia, after calcination below 600 °C, are very fine, and have a diffracting particle size in the range of 7-15 nm. As the tetragonal and cubic structures of zirconia have similar lattice parameters, it is difficult to distinguish between the two. The tetragonal structure can be identified only by the characteristic splittings of the Bragg profiles from the "c" index planes. However, these split Bragg peaks from the tetragonal phase in …

Electronic Controls For Swine Buildings, Douglas G. Overhults, R. S. Gates

Agricultural Engineering Extension Updates

This fact sheet discusses the use of electronic controllers to maintain the environment within swine barns. There are some special considerations when using electronic controllers to replace traditional control systems. Three main items are addressed in this fact sheet: 1) the selection of a controller, 2) installation considerations, and 3) protection against controller failure.

A Median-Filter-Based Ambiguity Removal Algorithm For Nscat, David G. Long, Scott J. Shaffer, R. Scott Dunbar, S. Vincent Hsiao

Faculty Publications

A description is given of the baseline NSCAT (the NASA scatterometer) ambiguity removal algorithm and the method used to select the set of optimum parameter values. An extensive simulation of the NSCAT instrument and ground data processor provides a means of testing the resulting tuned algorithm. This simulation generates the ambiguous wind-field vectors expected from the instrument as it orbits over a set of realistic mesoscale wind fields. The ambiguous wind field is then de-aliased using the median-filter-based ambiguity removal algorithm. Performance is measured by comparison of the selected wind fields with the true wind fields. Results have shown that …

Properties Of Glass Fabric Reinforced Silicone Glazing For Solar Applications In Rural Areas, Mohammed A Ahmed Dabbour

Archived Theses and Dissertations

No abstract provided.

Master Of Science, Computer Science 1991, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Master Of Science--Computer Information Systems 1991-92, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer And Information Sciences Master Of Science In Computer Information Systems Spring Courses 1991, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer And Information Sciences 1991, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer And Information Sciences 1991-1992 Catalog, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Center For Computer And Information Sciences Doctor Of Science In Computer Science 1991-1992, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

Compensation Modes In Counterdoped Rutile, M. M. Nasrallah, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

Thermogravimetric measurements were conducted on undoped, Nb⁵⁺ or Ta⁵⁺ donor-doped, and Al³⁺ acceptor doped rutile at 1000°C and 105-10-7 Pa oxygen activity. Nb⁵⁺ or Ta⁵⁺ doped rutile was counter doped by Al³⁺ in order to identify the role of Al³⁺ acceptor and its effect on donor doped rutile. Our results show that both dopants enter the lattice substitutionally for Ti⁴⁺, that Al³⁺ is as effective an acceptor as Nb⁵⁺ or that Ta⁵⁺ is effective as a donor, and the compensation occurs on a one-to-one basis. Earlier reports indicate …

Nebraska Summary S111: Lamborghini 115v Dt Also White 6105c And 6105ca, 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 …

Test 1642: Ford 3230 (8x2) Diesel 8-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 1644: Ford 3930 (8x2) Diesel 8-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 1646: Ford 8630 Powershift 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 1643: Ford 3430 (8x2) Diesel 8-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 1649: Case International 9230 And Steiger 9230 (12-Speeds) Diesels, 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 …