Engineering Commons^™

Experimental Demonstration Of An Algorithm To Detect The Presence Of A Parasitic Satellite, Vincent J. Dabrowski

Theses and Dissertations

Published reports of microsatellite weapons testing have led to a concern that some of these "parasitic" satellites could be deployed against US satellites to rendezvous dock and then disrupt, degrade disable or destroy the system. An effective detection method is essential. Various sensing solutions were investigated including visual, impact, and dynamic techniques. Dynamic detection, the most effective solution, was further explored. A detection algorithm was constructed and validated on the Air Force Institute of Technology's ground-based satellite simulator, SIMSAT. Results indicate that microsat microsatellites rigidly connected to a satellite can be detected with a series of small identical maneuvers utilizing …

Calculation Of The Actual Cost Of Engine Maintenance, Oguz Ezik

Theses and Dissertations

The cost of military operations has been difficult to determine, yet considered of high importance. The cost of an operation is largely dependent upon the answers to subordinate questions involving the discrete costs of military activities, like supporting individual items, While different cost estimates have received attention from the media, the question arises as to how accurate these figures are, There have been numerous studies performed by the Operations Research analysts to minimize costs while allocating scarce resources, However, the values of these studies are dependent upon whether or not the cost figures used are sufficiently "true" or accurate, This …

Modeling Homeland Security: A Value Focused Thinking Approach, Kristopher A. Pruitt

Theses and Dissertations

The events of September 11, 2001 have propelled the topic of homeland security to the forefront of national concern. The threat of terrorism within the United States has reached an unprecedented level. The pervasive vulnerabilities of the nation's critical infrastructure coupled with the destructive capabilities and deadly intentions of modern terrorists pose extraordinary risks. The United States must mitigate these risks while at the same time balancing the associated costs and impact on civil liberties. Currently, the United States lacks effective methods and measure for assessing the security of the homeland from acts of terrorism. This study outlines a first …

Effective Thermal Conductivity Estimates Of Particulate Mixtures, Christiaan Richter, Hendrik J. Viljoen, N.F.J Van Rensburg

Papers in Physical Properties

Several theories have been advanced to estimate effective thermal conductivities of particulate mixtures, but most theories have focused on the dilute case. A method is proposed to estimate the effective thermal conductivity coefficient of mixtures of arbitrary concentration. Earlier the authors developed a theory to determine the expected contact area between different species. This theory is employed to determine the Kapitza resistance of the heterogeneous mixture and forms part of an overall theory to estimate the effective thermal conductivity. Results are compared with other theoretical estimates and with experiments.

Inside Unlv, Gian Galassi, Richard Jensen, Carol C. Harter, Kenneth E. Marks

Inside UNLV

No abstract provided.

Shear Strengthening Of Rc Beams Using Carbon Fiber Reinforced Polymer Laminates, Zhichao Zhang

Dissertations

Shear failure is catastrophic and occurs usually without advanced warning, thus it is desirable that the beam fails in flexure rather than in shear. Many existing reinforced concrete (RC) members are found to be deficient in shear strength and need to be repaired. Deficiencies occur due to several reasons such as insufficient shear reinforcement or reduction in steel area due to corrosion, increased service load, and construction defects. Externally bonded reinforcement such as Carbon Fiber Reinforced Polymer (CFRP) provides an excellent solution in these situations.

In order to investigate the shear behavior of RC beams with externally bonded CFRP shear …

Flight Physician - January, 2003, Civil Aviation Medical Association

Browse all Civil Aviation Medical Association Newsletters

A twenty page newsletter of the Civil Aviation Medical Association. The newsletter provided news about civil aviation medicine and information related to the organization.

Guiding Growth: A Survey Of Tax Incentives, New England Environmental Finance Center, Muskie School Of Public Service

Legislation

Current development patterns and increased tax pressures in local municipalities combine to harm both Maine’s natural resources and its quality of life. Previous initiatives such as the implementation of zoning laws did not fully result in the desired outcomes. Zoning laws were often too flexible and often did not resist market and political pressures to change zoning regulations to allow development with possible economic growth. A sound taxation system or fee structure may be the solution to slow down development in natural areas and direct it towards areas appropriate for growth.

To protect Maine’s natural resources more successfully from future …

History Of Food Acceptance Research In The Us Army, Herbert L. Meiselman, Howard G. Schutz

United States Army: Publications

The history of food acceptance research by the US Army in Chicago and Natick is reviewed. The review covers the staff of the two research centers, the research programs, and the significant accomplishments of the Army laboratories from the 1940s to the present. Accomplishments begin with the development of the nine-point hedonic scale, and the development of the first Food Acceptance Laboratory. Further accomplishments include studies of sensory psychophysics, food preferences, food choice and food intake. The laboratories designed methods and conducted research on the role of consumer variables in the acceptance of food products and food service systems. Recent …

Global Optical Lightning Flash Rates Determined With The Forte Satellite, Tracy E. Light, Sean M. Davis, William Boeck, Abram Jacobson, David Suszcynsky

United States Department of Energy: Publications

Using FORTE photodiode detector (PDD) observations of lightning, we have determined the geographic distribution of nighttime flash rate density. We estimate the PDD flash detection efficiency to be 62% for total lightning through comparison to lightning observations by the TRMM satellite's Lightning Imaging Sensor (LIS), using cases in which FORTE and TRMM viewed the same storm. We present here both seasonal and total flash rate maps. We examine some characteristics of the optical emissions of lightning in both high and low flash rate environments, and find that while lightning occurs less frequently over ocean, oceanic lightning flashes are somewhat more …

Automated Distribution And Management Of Software And Hardware Configurations For Heterogeneous Wireless Devices, Grainne Foley

Theses

The continuing evolution of wireless networks and services has increased the complexity and diversity of wireless networks and devices, placing significant emphasis on the need for flexible device configuration management. Widely varying wireless technologies currently operate independently worldwide, making global wireless network access for the mobile user confusing and unwieldy. New technologies, network access methodologies and improved services further obscure the evolving environment. The focus of effort for this thesis is the development of a system to automate the distribution and management of software and hardware configurations that enable different levels of wireless device reconfiguration. The scope of investigation will …

Field Evaluation Of In-Situ Test Technology For Qc/Qa During Construction Of Pavement Layers And Embankments, Munir Darwish Nazzal

LSU Master's Theses

With the coming changes from an empirical to mechanistic-empirical pavement design, it becomes essential to move towards changing the quality control/quality assurance (QC/QA) procedures of compacted materials from a unit weight-based criterion to a stiffness/strength based criterion. The non-destructive in-situ tests such as Geogauge, Dynamic Cone Penetrometer (DCP), and Light Falling Weight Deflectometer (LFWD) can be used as effective tools in the assessment of subsurface conditions and in evaluating the stiffness of pavement materials and embankment. This thesis evaluates the potential use of these three devices to reliably measure the stiffness characteristics of highway materials for possible application in the …

Selected Chemoautotrophic Processes In Wastewater Treatment: Low Temperature Nitrification Inhibition By An Azo Dye And Biofiltration For Odor Control Of Hydrogen Sulfide, Ronald W. Martin Jr.

Dissertations, Master's Theses and Master's Reports - Open

Biochemical processes by chemoautotrophs such as nitrifiers and sulfide and iron oxidizers are used extensively in wastewater treatment. The research described in this dissertation involved the study of two selected biological processes utilized in wastewater treatment mediated by chemoautotrophic bacteria: nitrification (biological removal of ammonia and nitrogen) and hydrogen sulfide (H2S) removal from odorous air using biofiltration.

A municipal wastewater treatment plant (WWTP) receiving industrial dyeing discharge containing the azo dye, acid black 1 (AB1) failed to meet discharge limits, especially during the winter. Dyeing discharge mixed with domestic sewage was fed to sequencing batch reactors at 22oC and 7oC. …

Thermal Assessment Of Silicon-Based Composite Materials Used In Photovoltaics, Pavlos K. Bataglannis

Theses

Photovoltaics are devices that convert sunlight directly to electricity. It is well established that the conversion efficiency of mono and poly-crystalline silicon-based photovoltaic modules is inversely related to their temperature. Substantial improvements in operational performance can thus be achieved if the thermal energy accumulating in the material can be effectively dissipated.

Accurate modelling of modules would allow possible methods of thermal dissipation to be evaluated, and as a crucial component of the model, the thermal properties of the constituent materials of PV modules needed to be known. Special consideration needed to be given to the interfaces between dissimilar materials and …

Adaptive-Critic-Based Optimal Neurocontrol For Synchronous Generators In A Power System Using Mlp/Rbf Neural Networks, Jung-Wook Park, Ganesh K. Venayagamoorthy, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel optimal neurocontroller that replaces the conventional controller (CONVC), which consists of the automatic voltage regulator and turbine governor, to control a synchronous generator in a power system using a multilayer perceptron neural network (MLPN) and a radial basis function neural network (RBFN). The heuristic dynamic programming (HDP) based on the adaptive critic design technique is used for the design of the neurocontroller. The performance of the MLPN-based HDP neurocontroller (MHDPC) is compared with the RBFN-based HDP neurocontroller (RHDPC) for small as well as large disturbances to a power system, and they are in turn compared …

Mechanical Property Characterization Of Mouse Zona Pellucida, Yu Sun, Kai-Tak Wan, K. P. Roberts, J. C. Bischof, B. J. Nelson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Previous intracytoplasmic sperm injection (ICSI) studies have indicated significant variation in ICSI success rates among different species. In mouse ICSI, the zona pellucida (ZP) undergoes a "hardening" process at fertilization in order to prevent subsequent sperm from penetrating. There have been few studies investigating changes in the mechanical properties of mouse ZP post fertilization. To characterize mouse ZP mechanical properties and quantitate the mechanical property differences of the ZP before and after fertilization, a microelectromechanical systems-based multiaxis cellular force sensor has been developed. A microrobotic cell manipulation system employing the multiaxis cellular force sensor is used to conduct mouse ZP …

Wireless Local Area Network Security : An Investigation Into Security Tool Usage In Wireless Networks, Susan Webb

Theses : Honours

Many organisations and individuals installing wireless local area networks (WLANs), which are based on the IEEE 802.11 b standard, have little understanding of the security issues that surround this technology.

This study was initiated to determine how WLAN security issues affect organisations in Perth, Western Australia. The scope of the study was restricted to 802.llb WLANs operating in infrastructure mode, where all traffic is transmitted by wireless access points (APs). This study was conducted in two phases. The general aims of the first phase were to determine the number of detectable WLANs in the Perth Central Business District (CBD) and …

Implementation Of Adaptive Critic-Based Neurocontrollers For Turbogenerators In A Multimachine Power System, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents the design and practical hardware implementation of optimal neurocontrollers that replace the conventional automatic voltage regulator (AVR) and the turbine governor of turbogenerators on multimachine power systems. The neurocontroller design uses a powerful technique of the adaptive critic design (ACD) family called dual heuristic programming (DHP). The DHP neurocontroller's training and testing are implemented on the Innovative Integration M67 card consisting of the TMS320C6701 processor. The measured results show that the DHP neurocontrollers are robust and their performance does not degrade unlike the conventional controllers even when a power system stabilizer (PSS) is included, for changes in …

An Industrial Food Processing Plant Automation Using A Hybrid Of Pi And Fuzzy Logic Control, Ganesh K. Venayagamoorthy, D. Naidoo, P. Govender

Electrical and Computer Engineering Faculty Research & Creative Works

An industrial food processing plant consisting of nonlinear dynamics requires pressure and temperature controllers to be nonlinear. In this paper, nonlinear controllers are designed using fuzzy logic to augment the conventional pressure and temperature PI controllers for an industrial food processing plant. Simulation results are presented to show improvement in the plant response with the hybrid controllers.

Adaptive Neural Network Based Power System Stabilizer Design, Wenxin Liu, Ganesh K. Venayagamoorthy, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Power system stabilizers (PSS) are used to generate supplementary control signals for the excitation system in order to damp the low frequency power system oscillations. To overcome the drawbacks of conventional PSS (CPSS), numerous techniques have been proposed in the literature. Based on the analysis of existing techniques, this paper presents an indirect adaptive neural network based power system stabilizer (IDNC) design. The proposed IDNC consists of a neuro-controller, which is used to generate a supplementary control signal to the excitation system, and a neuro-identifier, which is used to model the dynamics of the power system and to adapt the …

Dual Heuristic Programming Excitation Neurocontrol For Generators In A Multimachine Power System, Ganesh K. Venayagamoorthy, Donald C. Wunsch, Ronald G. Harley

Electrical and Computer Engineering Faculty Research & Creative Works

The design of nonlinear optimal neurocontrollers that replace the conventional automatic voltage regulators for excitation control of turbogenerators in a multimachine power system is presented in this paper. The neurocontroller design is based on dual heuristic programming (DHP), a powerful adaptive critic technique. The feedback variables are completely based on local measurements from the generators. Simulations on a three-machine power system demonstrate that DHP-based neurocontrol is much more effective than the conventional proportional-integral-derivative control for improving dynamic performance and stability of the power grid under small and large disturbances. This paper also shows how to design optimal multiple neurocontrollers for …