Engineering Commons^™

Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush

Theses and Dissertations

Existing missile/target encounter modeling and simulation systems focus on improving probability of kill models. Little research has been done to visualize these encounters. These systems can be made more useful to the engineers by incorporating current computer graphics technology for visualizing and animating the encounter. Our research has been to develop a graphical simulation package for visualizing both endgame and full fly-out encounters. Endgame visualization includes showing the interaction of a missile, its fuze cone proximity sensors, and its target during the final fraction of a second of the missile/target encounter. Additionally, this system displays dynamic effects such as the …

Development And Validation Of An Experimental Test Rig For Electrohydrodynamic Enhancement Of Forced Convective Heat Transfer, William T. Caldwell

Theses and Dissertations

This report details the development of a facility for the experimental investigation of electrohydrodynamic (EHD) enhancement of forced convection heat transfer. The test facility was developed for the Thermal and Transparencies Laboratory (TATLAB), Air Force Research Laboratory (AFRL), for use in future research into the applicability of EHD for the miniaturization of Air Force heat exchangers. During this research, a closed l6op, medium scale electrohydrodynamic test rig was developed and brought online. The test fluid loop was integrated with a data acquisition and parameter control system. Basic loop and fluid performance testing was accomplished through the use of a 3mm …

Message-Bundle Converting In Intenet Protocol Multicast-Based High Level Architecture Exercises, Tracy A. Bobo

Theses and Dissertations

The Department of Defense is pushing for more wide-spread and realistic interactive training simulations which increases the demand on network capacity and resources. While network bandwidth is a measurable resource, packet bandwidth, or the number of packets-per-second (Pk/s) a host can handle, is a shifting commodity. This research analyzes host performance characteristics under varying data loads. The hosts include SGI single and multi-processor systems and Intel Pentium platforms using both Windows 95 and Linux Operating Systems. The networking media covers Ethernet, ATM and FDDI. For the ATM network, both AAL5 and IP over ATM were analyzed. With the data from …

Orbit Estimation Using Track Compression And Least Squares Differential Correction, Vincent J. Chioma

Theses and Dissertations

This thesis develops two methods of compressing a track of radar observations of a satellite into a single state vector and associated covariance matrix, and a method of estimating orbits using results from multiple tracks. The track compression uses least squares differential correction to determine a state vector at the central observation time. The resulting state vectors and covariance matrices are then used to estimate the satellite's orbit, also using least squares differential correction. Numerical integration using two-body, J₂ and an atmospheric drag model is used to represent the dynamics. This orbit estimation produces a state vector which includes …

Velocity Profiles And Skin Friction On A Ribletted Flat Plate In Adverse Pressure Gradient, Richard D. Branam

Theses and Dissertations

This project investigated the flow field characteristics over a flat, ribletted plate and the effects of an adverse pressure gradient on this flow field. Testing examined the development of the flow over the ribletted plate from laminar through fully turbulent flow fields. The flow field states (laminar, transitional, and turbulent) were determined using local turbulence intensity values and boundary layer profiles. Several parameters were examined to help better describe the flow characteristics, boundary layer profiles, and influence on skin friction drag. The skin friction drag coefficients were calculated using a numerical integration technique to determine an average value and scaled …

A Modeling Study For The Implementation Of In Situ Cometabolic Bioremediation Of Trichloroethylene-Contaminated Groundwater, John A. Christ

Theses and Dissertations

The limitations of conventional groundwater remediation technologies have led to the development of innovative technologies which may achieve national hazardous waste site remediation goals. Before an innovative technology can be implemented in the field, remedial project managers, regulators and other stakeholders require adequate modeling tools to help assess the applicability of the technology at a particular site. This modeling study investigates how an innovative technology, in situ cometabolic bioremediation, might be implemented to remediate a TCE-contaminated site, under different site conditions. A steady-state model is developed which couples an analytical expression to simulate the effect of flow between multiple pumping …

Fatigue Behavior Of A Quasi-Isotropic Graphite/Epoxy Laminate Embedded With A Piezoelectric Sensor, Jon M. Coleman

Theses and Dissertations

This study primarily investigated the mechanical effects of embedding piezoelectric sensors on the tensile and fatigue strength of a quasi-isotropic, carbon-epoxy laminate. A secondary focus was the investigation of the sensor degradation under tensile loading. A [0 | ±45 | 90]_s laminate was fabricated from Hercules AS4/3501-6 pre-preg tape. Specimens were first tested monotonically to obtain an average ultimate tensile strength and to detail the progression of damage. The fatigue tests were tension-tension, R=0.1, 10 Hz, constant amplitude. Results indicated that the embedded piezoelectric sensors did not have a significant effect on the tensile strength of the laminate. Specimens …

Investigation Of Biodegradation Processes In Solid Waste Landfills, Philip A. Colborn

Theses and Dissertations

Greater demands on landfill capacity, stricter regulations intended to minimize landfill environmental impacts, and the economic potential associated with landfill operations have shifted the emphasis of landfill disposal toward methods concerned with the long term performance and capacity of landfills. Two opposing philosophies have emerged in constructing and managing landfills: the dry tomb and the wet cell. The key to managing a landfill from the wet cell viewpoint is first understanding the biodegradation processes occurring within the landfill. This thesis attempts to determine the fundamental processes responsible for the degradation of solid waste by employing a system dynamics approach. A …

Multiple Model Adaptive Estimation And Control Redistribution Performance On The Vista F-16 During Partial Actuator Impairments, Curtis S. Clark

Theses and Dissertations

Multiple Model Adaptive Estimation with Control Reconfiguration (MMAE/CR) capability to estimate and compensate for partial actuator failures, or "impairments" is investigated using the high-fidelity, nonlinear, six-degree-of-freedom, VISTA F-16 simulation which currently resides on the Simulation Rapid-Prototyping Facility (SRF). After developing a model for inserting partial actuator impairments into the VISTA F-16 truth model, research begins with a battery of single actuator impairment tests. This stage of research explores the capability of the existing MMAE algorithm to estimate single, partial actuator impairments, and helps to define refinements and expansions needed in the MMAE algorithm for the second phase of research: the …

Breast Cancer Mass Detection Using Difference Of Gaussians And Pulse Coupled Neural Networks, Donald A. Cournoyer

Theses and Dissertations

CAD, serving as a second reader, has been shown to improve the success of radiologists at detecting breast cancer. This thesis will develop a new algorithm to identify masses in mammograms. The system developed for this thesis will be capable of assisting a radiologist in making decisions.

Satellite Integrated Power And Attitude Control System Design Study, Stephen A. Fischer, Dwight D. Fullingim, Brian L. James, James M. Valenti, Jorg D. Walter, Paul J. Cotter, William A. Seeliger

Theses and Dissertations

Technological advances have brought Flywheel Energy Storage (FES) systems to the point where they can be used in satellites as replacements for chemical batteries. Flywheels have characteristics that may overcome limitations inherent in batteries. These characteristics include high specific energy, minimal degradation over time, and precise knowledge of charge level. A further advantage of flywheels is that, in a combined system, they can be used to replace traditional attitude control hardware. These Integrated Power and Attitude Control Systems (IPACS) show the potential to have less mass than the systems they replace. The question this study seeks to answer is, "In …

Effects Of Near-Field Scatterers On Space-Time Adaptive Processing, Jonathan W. Fitton

Theses and Dissertations

Near-field scatterers, such as the wing of an airplane, can affect the ability of the processor to null out clutter and jammer signals. The target, clutter, and jammer signals will reflect off the near-field scatterers into the array and appear to be coming from a direction different from their true sources. This thesis develops a theoretical model for the direct path and scattered path signals from the target, clutter, and jamming signals. The optimum weight vector, normally computed using the steering vector to the target and the covariance matrix of the undesired signals, must now include the effects of the …

Preparation Of High Rate Discharge Foamed Ni-Cd Battery, Yuming Wang, Jinsheng Chen

Journal of Electrochemistry

A novel device of SC type foamed NiCd battery is presented, in which, the innerresistance of battery is appeared to be reduced, and the electrode performance is gained to very improved, and so, this battery can be suited to using of the powerdrive pistol drill.

Advances In Solid Polymer Electrolytes, Liming Ding, Shaojun Dong, Erkang Wang

Journal of Electrochemistry

The formation, classification, applications and ion-transport mechanism studies of solid polymer electrolytes were reviewed. While the recent SPE reports on the preparation of novel materials, the full structure determinations of PEO/salt complexes, the exploration of ion-transport mechanism and the applications in electrochemical devices being introduced, some prospects on the future SPE research were suggested.

Li/Α-Sn(Hpo4)2 Cell And Its Reaction Mechanism, Yuan Lin, Runliang Cai, Haoqing Wu

Journal of Electrochemistry

The discharge mechanism of Li/α-Sn(HPO₄)₂ cell has been investigated by means of X-ray diffraction, XPS and cyclic voltammetry methodes. It has been shown that the electrochemical intercalation reation exists in the cathode material. There is a new phase after some degree of intercalation. With potential step and galvanostatic techniques, the chemical diffusion cofficients of Li⁺ in Li_xSn(HPO₄)₂ is estimated to be 10^-12～10^-13 cm²·s^-1.

Mechanism Of Electrodeposition Of Cu/Co Multilayer Thin Films, Jiangyun Xue, Jixun Wu, Dejun Yang

Journal of Electrochemistry

The mechanism of electrodeposition of Cu/Co multilayer thin films has been studied by means of potentodynamic sweep, cyclic voltammetry sweep and AC impendance. The results indicated that the copper deposition is mass transfer controlled process and the cobalt deposition is related to the absorbed intermediate species such as Co(OH)_ads. The cobalt ions first form Co(OH)_ads, then was deoxygenated to cobalt on the electrode surface.

The Effect Of Solution Composition On The Corrosion Behavior Of Electrodeposited Zinc Powder, Qingwen Li, Qin Yang, Xi Xia

Journal of Electrochemistry

Zinc powder as a widely anode material can be electrowon from ZnCl₂ or ZnO+KOH media. The properties of zinc powder are likely to be modified with electrolytic conditions such as the composition of bath solution, electrolysis manner, current density and additives etc.. In this paper, we have discussed the effect of the compositions of bath solution on the microstructure and corrosion resistance of zinc powder.

The Activity Of Alloy Cu-Ni Electrode In Electroreduction Of Aromatic Nitro-Compounds, Chunan Ma, Shaoping Tong, Xiaojun Cheng, Hui Wang

Journal of Electrochemistry

Cu-Ni alloy on the basis of copper at different ratio Cu/Ni are prepared by codepostion. The cathode activtiy of film are studied by steady-state polarization for electroreduction nitro-benzene (NB) and 1,5-dinitroanthraquinone (1,5-DNA) to p-aminophenol and 1,5-diamino-4,8-dihydroanthraquinone respectly. The results show that the alloy cathodes at different ratio Cu/Ni have different exchange current density (i^o) and apparent activition energy (E_A). The alloy (CN-30) has maximal i^o and minimal E_A by codeposition at the following conditions: electrolyte: 0.05 mol/L CuSO₄·5H₂O+0.6 mol/L NiSO₄·6H₂O+0.25 mol/L Na₃Cit·2H₂O; …

Photoluminescence Of Photoelectrochemically Etched N+-Si, Guozheng Li, Chengqian Zhang, Xiumei Yang

Journal of Electrochemistry

PS layer on n⁺-Si with (111) orientation prepered by means of photoelectrochemically etched has photo-luminescent (PL) ability like PS layer on usual n-Si. The data of PL spectra and quenching are given.

Study On The Oxygen Electrodes Of Alkaline Fuel Cells Effect Of Dopant On The Activity Of Ag/C Catalyst, Jiawei Teng, Linhua Jin, Luncheng Tang

Journal of Electrochemistry

A new kind of nonnoble catalyst for the oxygen electrodes of Alkaline Fuel Cells was investigated. The AgNiBiHg/C catalyst, which was prepared by chemical reduction, was active for the cathodic reduction of oxygen in alkaline fuel cells. It was found that the catalytic activity was improved by adding Ni, Bi, Hg to Ag/C catalyst, and the maximum activity was observed at Ag50%-Ni2%-Bi3%-Hg3%-C42%(wt%). XRD inconjunction with SEM indicated that the crystalline silver turned into amorphous in the presence of doping agents and the grain size of silver was reduced. No dramatic deactivation of the catalyst occured after 5200 hours of service.

Development Of A New Type Ni-S Evolution Hydrogen Electrode For Water Electrolysis, Xiaoyou Yuan, Jinyu Wang

Journal of Electrochemistry

A new type evolution hydrogen electrode NiS(N) has been made from nickel plating electrode in NiSO₄CS(NH₂)₂ bath by electrodeposition. It is analyzed by SEM and X-ray energy spectrum. The NiS(N) electrode is different from the NiS(O) electrode (which is used in plant at present time) in surface metallograph configuration and surfer content. The results of measurement polarization curves and water electrolysis 480 hours at 5 000 A·m^-2 show that the evolution hydrogen overpotential of NiS(N) electrode is decreased at least 160 mV relative to NiS(O) electrode and the stablisum of NiS(N) electrode is better …

Molten Carbonate Fuel Cell Materials And Technology, Naichao Li, Baolian Yi

Journal of Electrochemistry

Molten Carbonate Fuel Cell materials are reviewed, and the technology of Molten Carbonate Fuel Cell are discussed.

Study On Perchlorate Produced By Electrolysis With Oxygen Cathode, Zhigang Shao, Baolian Yi, Naichao Li, Ming Han

Journal of Electrochemistry

A new method of measuring the flow capacity of cell gas in the perchlorate cell process equipped with an oxygen cathode is applided to investigate the influence of changes in the concentration of solution (chloride, chlorate, perchlorate and metal ion) and changes in the operation parameters (current density, temperature and pH) on perchlorate current efficiency. The main abstacle that the oxygen cathode is used in the perchlorate cell process is put forward and a method is provided to resolve it.

The Effect Of Bismuth On Microstructure Of The Cathodic Copper Deposition Of Copper Electrorefining, Daorong Lu, Jianxing Lin

Journal of Electrochemistry

The electrocrystal formation, crystal orientation and the chemical composition of the cathodic copper deposition in the presence of Bi³⁺ in the electrolyte of acidified CuSO₄ are studies by scanning electron microscopy, X-ray diffraction, atomic absorption and EDAM. The results indicate that the Bi could′t deposit on cathode when copper electrolysed at common current density i=200 A·mol/L^-2 and t=60 ℃. Bi³⁺ scarcely effected on the crystal orientation (220) of copper deposition. High concentration Bi³⁺ in the electrolyte promoted (220) growth and inhibited the other crystal orientation growth. Bi³⁺ effected on electrocrystal formation and the cell …

Energy Needs During Disasters: Workshop Summary Report, Florida Solar Energy Center, Gerard Ventre

FSEC Energy Research Center®

When natural disasters, such as hurricanes, earthquakes and floods, occur, thousands of people can be left without homes, electrical power, communications, potable water, and food storage capabilities. Adequate electrical power is imperative for both disaster relief operations and community rebuilding. However, the disaster may have disrupted the commercial power supply to a community, requiring disaster relief agencies to rely on alternative sources of power. Photovoltaic-powered equipment provides electrical power which is renewable, quiet, and safe, and which can be used for many essentials of disaster relief efforts, such as refrigeration, communications and lighting. However, at present, photovoltaic (PV) technology is …

An Analysis Of Current Interruption Upon The Behavior Of Light Bulb Filament During Initial Aircraft Impact In Support Of Aircraft Accident Investigations, Daniel J. Larow

Master's Theses - Daytona Beach

The purpose of analyzing annunciator panels, warning, and indicator lamps is to determine the state ("on" or "off") of each light bulb immediately before the impact. Determination of the state of lamps may help investigators determine the probable cause of the accident. The information gained from the lamp's filaments may be used to infer the aircraft's operational parameters prior to impact and to a qualitative appreciation of the severity of the accident. It is generally agreed that upon impact the filament of an unlit bulb will fracture without deformation and the filament of a lit bulb will display plastic deformation …

Tractor Test Museum Commttee Minutes November 19th, 1997, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Update on Roof Progress Big Red Club State Fair Project

Pv Powering A Weather Station For Severe Weather, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

A natural disaster, such as Hurricane Andrew, destroys thousands of homes and businesses. The destruction from this storm left thousands of people without communications, potable water, and electric power. This prompted the Florida Solar Energy Center to study the application of solar electric power for use in disasters.

During this same period, volunteers at the Tropical Prediction Center at the National Hurricane Center (NHC) and the Miami Office of the National Weather Service (NWS) were working to increase the quantity and quality of observations received from home weather stations.

Many weather data collecting stations are at remote sites, which are …

Infrared Optical Properties Of Mixed-Phase Thin Films Studied By Spectroscopic Ellipsometry Using Boron Nitride As An Example, Mathias Schubert, B. Rheinlander, E. Franke, H. Neumann, T. E. Tiwald, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

We present a microstructure-dependent anisotropic infrared-optical dielectric function model for mixed-phase polycrystalline material from which we derive the transverse and longitudinal-optical modes observable in thin films. Infrared ellipsometry over the wavelength range from 700 to 3000 cm^-1 is then used to determine the phase and microstructure of polycrystalline and multilayered hexagonal and cubic boron nitride thin films deposited by magnetron sputtering onto (100) silicon. The ellipsometric data depend on the thin-film multilayer structure, the layer-phase composition, and the average orientation of the hexagonal grain c axes. In particular, we demonstrate the existence of spectral shifts of longitudinal optical phonons …

Complete-Range Activity-Based Rtl Power Estimation, Nur Kurt-Karsilayan

Dissertations and Theses

In recent years, power consumption has become a major concern in the electronic industry. Power reduction can be accelerated in the design cycle by fast and accurate power estimation tools. Since the units of lower-levels of design abstraction are transistors or gates, power estimation becomes a slow process at these levels. Therefore designers need to have tools for fast and accurate power estimation at the higher levels of design abstraction such as register transfer level (RTL).

A novel RTL power estimation technique called CRAB-RPE will be presented in this thesis. The CRAB power model is built upon four important properties …