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2009

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Articles 31 - 60 of 4157

Full-Text Articles in Engineering

Passive Earth Pressures On A Pile Cap With A Dense Sand Backfill, Robert Ashall Marsh Dec 2009

Passive Earth Pressures On A Pile Cap With A Dense Sand Backfill, Robert Ashall Marsh

Theses and Dissertations

Pile groups are often used to provide support for structures. Capping a pile group further adds to the system's resistance due to the passive earth pressure from surrounding backfill. While ultimate passive earth pressure under static loading conditions can be readily calculated using several different theories, the effects of cyclic and dynamic loading on the passive earth pressure response are less understood. Data derived from the full-scale testing of a pile cap system with a densely compacted sand backfill under static, cyclic, and dynamic loadings was analyzed with particular focus on soil pressures measured directly using pressure plates. Based on …

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Enhance Diamond Coating Adhesion By Oriented Interlayer Microcracking, Habio Guo, Xingcheng Xiao, Yue Qi, Zhi-Hui Xu, Xiaodong Li Dec 2009

Enhance Diamond Coating Adhesion By Oriented Interlayer Microcracking, Habio Guo, Xingcheng Xiao, Yue Qi, Zhi-Hui Xu, Xiaodong Li

Faculty Publications

In this paper, we report a microcrack toughening mechanism for enhancing the adhesion of diamondcoating. The oriented microcracks were formed within the TiC interlayer to dissipate strain energy and accommodate deformation via the crack opening-closing mechanism, thus enhancing the coating/substrate interfacial toughness. The delamination of diamondcoating was effectively prevented when the parallel microcracks were confined within the interlayer and arrested at interfaces of coating/interlayer/substrate. Density functional theory calculations revealed that the highly anisotropicfracture strength of the TiC phase energetically favors crack initiation and propagation along (100) planes only, which are 54.7° away from the interface. These microcracks are constrained inside …

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Design And Implementation Of Dstatcom For Fast Load Compensation Of Unbalanced Loads, Wei-Neng Chang, Kuan-Dih Yeh Dec 2009

Design And Implementation Of Dstatcom For Fast Load Compensation Of Unbalanced Loads, Wei-Neng Chang, Kuan-Dih Yeh

Journal of Marine Science and Technology–Taiwan

This paper proposes a distribution level static synchronous compensator (DSTATCOM) for fast load compensation of unbalanced loads in electric power distribution systems. For fast response requirement, a new feedforward compensation scheme is derived and employed in the paper. First, the compensation scheme of the DSTATCOM is derived with the symmetrical components method. Then, computer simulation with the program Matlab/Simulink preliminarily verifies the effectiveness of the proposed DSTATCOM. Accordingly, a hardware prototype is built with a floating-point DSP TMS320C6711-based system. Use of a current-regulated PWM (CRPWM) inverter as the power stage of the DSTATCOM generates needed compensation currents for real-time load …

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A Novel Stability Condition And Its Application To Ga-Based Fuzzy Control For Nonlinear Systems With Uncertainty, Po-Chen Chen, Cheng-Wu Chen, Wei-Ling Chiang, Ken Yeh Dec 2009

A Novel Stability Condition And Its Application To Ga-Based Fuzzy Control For Nonlinear Systems With Uncertainty, Po-Chen Chen, Cheng-Wu Chen, Wei-Ling Chiang, Ken Yeh

Journal of Marine Science and Technology–Taiwan

In this study, we strive to combine the advantages of fuzzy logic control (FLC), genetic algorithms (GA), H∞ tracking control schemes, smooth control and adaptive laws to design an adaptive fuzzy sliding model controller for the rapid and efficient stabilization of complex and nonlinear systems. First, we utilize a reference model and a fuzzy model (both involving FLC rules) to describe and well-approximate an uncertain, nonlinear plant. The FLC rules and the consequent parameter are decided on via GA. A boundary-layer function is introduced into these updated laws to cover modeling errors and to guarantee that the state errors converge …

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Production Of Iron Using Environmentally-Benign Renewable Or Recycled Reducing Agents, Timothy C. Eisele, Surendra Komar Kawatra Dec 2009

Production Of Iron Using Environmentally-Benign Renewable Or Recycled Reducing Agents, Timothy C. Eisele, Surendra Komar Kawatra

Michigan Tech Patents

To produce metallic iron from iron ore, a composition comprising a mass of material formed from a mixture of iron ore particles and particles of a reductant that is either a biomass material in particulate form or a plastic resinous material in particulate form is used. The reductant can also be a mixture of biomass material and resin in any proportions. The mass of material comprises at least one body having a shape adapted for smelting such as pellets, briquettes, pieces or lumps. The pellets have sufficient cohesion to maintain the shape into which they have been formed. The invention …

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Robust Stability Bounds For Lur'e System With Parametric Uncertainty, Chyun-Chau Fuh, Pi-Cheng Tung Dec 2009

Robust Stability Bounds For Lur'e System With Parametric Uncertainty, Chyun-Chau Fuh, Pi-Cheng Tung

Journal of Marine Science and Technology–Taiwan

The robust stability of Lur’e system with parametric uncertainty is studied through the Popov-Lyapunov approach. Robust stability bounds of such a system are presented. Since we avoid using norm forms and absolute values, the obtained stability bounds are less conservative. An example demonstrating the feasibility of our method is illustrated

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Degradation Of The Bond Strength Between Rebar And Concrete Due To The Impressed Cathodic Current, Jiang-Jhy Chang, Weichung Yeih, Ran Huang Dec 2009

Degradation Of The Bond Strength Between Rebar And Concrete Due To The Impressed Cathodic Current, Jiang-Jhy Chang, Weichung Yeih, Ran Huang

Journal of Marine Science and Technology–Taiwan

In this study, the degradation of the bond strength between the steel rebar and concrete by the impressed cathodic current was investigated. Experimental results showed that the bond strength degraded as the charging current density and the polarization time increased basically. A new parameter representing the total transferred electrons per unit protected area was proposed, and the bond strength was found to decrease as the parameter increased after some value.

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Spectroscopicellipsometer And Polarmeter Systemis, John A. Woollam, Blaine D. Johs, Craig M. Herzinger, Ping He, Martin M. Liphardt, Galen L. Pfeiffer Dec 2009

Spectroscopicellipsometer And Polarmeter Systemis, John A. Woollam, Blaine D. Johs, Craig M. Herzinger, Ping He, Martin M. Liphardt, Galen L. Pfeiffer

Department of Electrical and Computer Engineering: Faculty Publications

A rotating compensator spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for Supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, the system being functionally present in an environmental control chamber and therefore suitable for application in wide spectral range, (for example, 130-1700 nm). Preferred compensator design involves a Substantially achromatic multiple element compensator systems wherein multiple total internal reflections enter retardance into an entered beam of electromagnetic radiation, and the elements thereof are oriented to minimize changes …

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Dsp-Based Implementation Of A Real-Time Doa Estimator For Underwater Acoustic Sources, Sheng-Yun Hou, Shun-Hsyung Chang, Hsien-Sen Hung, Jiang-Yao Chen Dec 2009

Dsp-Based Implementation Of A Real-Time Doa Estimator For Underwater Acoustic Sources, Sheng-Yun Hou, Shun-Hsyung Chang, Hsien-Sen Hung, Jiang-Yao Chen

Journal of Marine Science and Technology–Taiwan

Many direction-of-arrival (DOA) estimation algorithms for acoustic sources based on sensor array measurements have been well developed and verified via computer simulations and/or small-scale water trough experiments. However, these results are not in practical use because the testing scenarios may not reflect real underwater environments. In order to have a better understanding of DOA estimation in sea experiments, a prototype of DSP-based acoustic DOA estimator is designed and implemented. The prototype system is based on TMS320VC33 digital signal processor and is validated by both computer simulation and experiments performed on the shallow water of Bi-Sha fishery harbor located near the …

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Cpt-Based Simplified Liquefaction Assessment By Using Fuzzy-Neural Network, Shuh-Gi Chern, Ching-Yinn Lee Dec 2009

Cpt-Based Simplified Liquefaction Assessment By Using Fuzzy-Neural Network, Shuh-Gi Chern, Ching-Yinn Lee

Journal of Marine Science and Technology–Taiwan

Due to the difficulty and the cost of obtaining high quality undisturbed samples, simplified methods based on in-situ tests such as the standard penetration test (SPT) and the cone penetration test (CPT) are preferred by geotechnical engineers for evaluation of earthquake induced liquefaction potential of soils. Because of the increasing popularity worldwide of the CPT for site characterization, significant progress on the CPTbased methods has been made. In most existing CPT-based methods, empirically determined curves are used to predict liquefaction and non-liquefaction. These empirical curves are generally relied on engineering judgment and are essentially performance functions that were established based …

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Fundamental Properties Of Linear Ship Steering Dynamic Models, Ching-Yaw Tzeng, Ju-Fen Chen Dec 2009

Fundamental Properties Of Linear Ship Steering Dynamic Models, Ching-Yaw Tzeng, Ju-Fen Chen

Journal of Marine Science and Technology–Taiwan

This paper is concerned with the fundamental properties associated with the Nomoto models. Specifically, the state space model associated with the first order Nomoto model is both observable and controllable. The state space model associated with the second order Nomoto model is also observable; however, it is controllable only if the effective sway time constant is different from the effective yaw time constant. The zero appearing in the transfer function model is found responsible for the overshoot behaviors, which are typical in the yaw rate for large rudder angle steering. This suggests that a second order Nomoto model is more …

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A Representation Of Gm-Variation In Waves By The Volterra System, Jianbo Hua, Wei-Hui Wang, Jiang-Ren Chang Dec 2009

A Representation Of Gm-Variation In Waves By The Volterra System, Jianbo Hua, Wei-Hui Wang, Jiang-Ren Chang

Journal of Marine Science and Technology–Taiwan

As known, the variation of the metacentric height of a ship in irregular waves is not a pure linear process, particular when a ship has large beam to draught ratio and large flare near the waterline at bow and stern. This kind of unconventional hull form is usually adopted for modern RoRo-ship, cruise-ship etc. which allows large cargo space and high service speed. In this paper, the GM-variation is derived into a function series with respect to the variation order and represented by the Volterra system. The transfer functions for the different orders are integrated numerically or analytically through expressing …

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Spanning Trees For Binary Directed De Bruijn Networks And Their Applications To Load Balancing, Ming-Bo Lin, Ming-Hong Bai, Gene Eu Jan Dec 2009

Spanning Trees For Binary Directed De Bruijn Networks And Their Applications To Load Balancing, Ming-Bo Lin, Ming-Hong Bai, Gene Eu Jan

Journal of Marine Science and Technology–Taiwan

One of the major reasons of using parallel computer systems is that they have the potential for improving performance and resource sharing. To achieve this, an efficient way must be provided to broadcast a message or messages from a node to every other nodes in the system. However, the efficiency of transferring messages in a system is determined by the architecture of the underlying interconnection network of the system. In this paper, we consider the systems based on binary directed de Bruijn networks and define two shortest path spanning trees: the upward-0 spanning tree and the downward-0 spanning tree, to …

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Non-Darcy Flow And Heat Transfer In A Porous Insulation With Infiltration, Hwa-Chong Tien, Kwang-Sheng Chiang Dec 2009

Non-Darcy Flow And Heat Transfer In A Porous Insulation With Infiltration, Hwa-Chong Tien, Kwang-Sheng Chiang

Journal of Marine Science and Technology–Taiwan

This work analyzes non-Darcy flow and heat transfer in a vertical slot filled with a porous matrix. The left and right vertical boundaries of the porous system are maintained at higher and lower temperatures, respectively. The horizontal boundaries are assumed to be impermeable and insulated. The vertical boundaries are either completely impermeable, where free convection is induced, or partially permeable in a way to simulate the wall leakage in the building materials, where both air infiltration and free convection exist. The non-Darcy model, which includes the Brinkman and Forchheimer extensions along with the convection terms, is employed to describe the …

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Development Of A Methodology For Numerical Simulation Of A D C Arc Discharge In A Liquid Dielectric, Christopher James Lewis Dec 2009

Development Of A Methodology For Numerical Simulation Of A D C Arc Discharge In A Liquid Dielectric, Christopher James Lewis

Theses and Dissertations

The majority of literature regarding the numerical simulation of arc discharges in gaseous environments has used a plasma physics approach. Virtually all simulations treat the discharge as an idealized gaseous plasma, which can be described by temperature, pressure, and electric field. This approach can work well if the media is a shielding gas such as Argon; however, the approach does not work well for processes such as underwater welding, EDM, and underwater discharges used to generate high purity particles. The reason these discharges do not have many extensive simulation efforts as described in the literature is because they occur in …

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Modeling Resilient Modulus Of Unbound Granular Materials Under Repeated Loading, Cheng Chen, Louis Ge, Jia Sheng Zhang Dec 2009

Modeling Resilient Modulus Of Unbound Granular Materials Under Repeated Loading, Cheng Chen, Louis Ge, Jia Sheng Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Resilient modulus of unbound granular materials is a key design parameter for mechanistic empirical pavement design. But the complexity of the affected factors has made it challenging and difficult for practical designers and researchers to find an appropriate model to describe the entire stress-strain response where the plastic deformation is accumulated during the repeated loading condition. a cyclic plasticity model based on fuzzy sets plasticity theory is presented in this paper to model the resilient modulus and permanent strain behavior of unbound granular materials under repeated loading. the concept of the fuzzy set plasticity is first introduced, followed by its …

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Energy Dissipation Caused By Asphalt Roadway Gouges For Use In Accident Reconstruction, Charles L. Crosby Dec 2009

Energy Dissipation Caused By Asphalt Roadway Gouges For Use In Accident Reconstruction, Charles L. Crosby

Theses and Dissertations

In reconstruction of on-roadway vehicle accidents, roadway surface gouges and the forces and energy attributed to the related vehicle components become important keys to resolving an accurate accident reconstruction. These roadway gouge forces vary depending upon such factors as surface temperature and the velocity and geometry of the gouging mechanism. Accounting for the forces applied to vehicle components and the energy dissipated from such forces can be helpful in accident reconstruction where supporting data exists. This research documents the force necessary to create a given roadway gouge geometry. Controlled pavement gouging tests were performed using roadway surface temperature and gouging …

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Computational Modeling Of Biochemical Systems Using Cellular Automata, Advait Apte Dec 2009

Computational Modeling Of Biochemical Systems Using Cellular Automata, Advait Apte

Theses and Dissertations

Biological systems exhibit complex behaviors through coordinated responses of individual biological components. With the advent of genome-scale techniques, one focus has been to develop methods to model interactions between components to accurately describe intact system function. Mathematical modeling techniques such as constraint-based modeling, agent-based modeling, cellular automata (CA) modeling and differential equation modeling are employed as computational tools to study biological phenomenon. We have shown that cellular automata simulations can be used as a computational tool for 12 predicting the dynamics of biological systems with stochastic behavior. The basic premise for the research was the observations made during a study …

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Decision-Based Data Fusion Of Complementary Features For The Early Diagnosis Of Alzheimer's Disease, Metin Ahiskali Dec 2009

Decision-Based Data Fusion Of Complementary Features For The Early Diagnosis Of Alzheimer's Disease, Metin Ahiskali

Theses and Dissertations

As the average life expectancy increases, particularly in developing countries, the prevalence of Alzheimer's disease (AD), which is the most common form of dementia worldwide, has increased dramatically. As there is no cure to stop or reverse the effects of AD, the early diagnosis and detection is of utmost concern. Recent pharmacological advances have shown the ability to slow the progression of AD; however, the efficacy of these treatments is dependent on the ability to detect the disease at the earliest stage possible. Many patients are limited to small community clinics, by geographic and/or financial constraints. Making diagnosis possible at …

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Labrat™: Miniature Robot For Students, Researchers, And Hobbyists, Paul Robinette, Ryan Meuth, Ryanne Dolan, Donald C. Wunsch Dec 2009

Labrat™: Miniature Robot For Students, Researchers, And Hobbyists, Paul Robinette, Ryan Meuth, Ryanne Dolan, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

LabRat™ is an autonomous, self-contained mobile robot kit with batteries, motors, two bumper whisker sensors, and three infrared proximity sensors that double as channels for "Rat-to-Rat" communication. the vehicle determines its position with an optical sensor that detects movement in both lateral directions. the LabRat™ design is completely open source, including software examples and libraries. LabRat™ is designed to fit inside the body of a computer mouse and has applications in the classroom, the lab and the home. the device has been successfully used in an undergraduate robotics class. © 2009 IEEE.

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Investigation Of The Mechanical Properties Of Poly (Ethylene Glycol) Diacrylate By Nanoindentation Using Atomic Force Microscopy, Zouheir Drira Dec 2009

Investigation Of The Mechanical Properties Of Poly (Ethylene Glycol) Diacrylate By Nanoindentation Using Atomic Force Microscopy, Zouheir Drira

Theses and Dissertations

Poly (ethylene glycol) (PEG) hydrogel based polymers are among the most widely used synthetic materials for biomedical applications. Because of their biocompatibility, and ease of fabrication, hydrogels are highly suitable for use as constructs to engineer tissues as well as for cell transplantation. A critical parameter of importance for PEG hydrogels is their mechanical properties which are highly dependent on the environmental conditions. Properties of PEG-based hydrogels can be engineered to resemble scaffolds composed of extracellular matrix molecules, which provide structural support, adhesive sites and mechanical as well as biomechanical signals to most cells. The mechanical properties of these synthetic …

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Extending The Strategy Based Risk Model Using The Delphi Method: An Application To The Validation Process For Research And Developmental (R&D) Satellites, Amanda J. Langenbrunner, Mary R. Trautwein Dec 2009

Extending The Strategy Based Risk Model Using The Delphi Method: An Application To The Validation Process For Research And Developmental (R&D) Satellites, Amanda J. Langenbrunner, Mary R. Trautwein

Theses and Dissertations

The validation between a research and developmental satellite and its ground system is critical to ensuring the success on-orbit. However, the exact process for completing validation is not documented, frequently underfunded, and accomplished ad hoc. This leads to debate regarding maintenance of budget and schedule, while ensuring on-orbit success. This thesis examines readiness and on-orbit activities within the U.S. Air Force Space Development and Test Wing's Research Development Test and Evaluation Support Complex. Combining historical data with the consultation of subject matter experts, a validation process was defined. Risks associated with this process were then analyzed using the Strategy Based …

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Analyzing Systems Integration Best Practices And Assessment In Dod Space Systems Acquisition, Douglas R. Dillon, Enriqueta M. Styres Dec 2009

Analyzing Systems Integration Best Practices And Assessment In Dod Space Systems Acquisition, Douglas R. Dillon, Enriqueta M. Styres

Theses and Dissertations

Senior leadership of the Air Force's Space and Missile Center suggested an investigation of systems integration within the space acquisition community in the fall of 2008. This thesis performs that investigation. A review concluded that while Systems Integration (SI) is extensively discussed as an area deserving considerable attention in the Systems Engineering literature, definitions are weak and methods and tools non-existent. Known SI activities are not being traced and assessed for adequacy throughout system development. Employing the Space System Acquisition Lifecycle Framework as the environment for this research, a method of characterizing and tracing SI throughout a program‘s lifecycle by …

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Comparative Study Of Population Based Techniques For Power System Stabilizer Design, Pinaki Mitra, Chuan Yan, Lisa Grant, Ganesh K. Venayagamoorthy, Komla Folly Dec 2009

Comparative Study Of Population Based Techniques For Power System Stabilizer Design, Pinaki Mitra, Chuan Yan, Lisa Grant, Ganesh K. Venayagamoorthy, Komla Folly

Electrical and Computer Engineering Faculty Research & Creative Works

Power System Stabilizers (PSSs) are used in interconnected power systems in order to mitigate low frequency oscillations. the comparison of the performances of four advanced population-based techniques in tuning the parameters of PSS in a three-machine-nine-bus test system is presented in this paper. the algorithms considered in this paper are A) Differential Evolution based Particle Swarm Optimization (DEPSO), b) Modified Clonal Selection Algorithm (MCSA), c) Small Population based Particle Swarm Optimization (SPPSO) and d) Population based Incremental Learning (PBIL). the comparative study is focused on the frequency domain performances. It is observed that MCSA is performing better than the other …

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Short To Medium Range Time Series Prediction Of Solar Irradiance Using An Echo State Network, Stephen M. Ruffing, Ganesh K. Venayagamoorthy Dec 2009

Short To Medium Range Time Series Prediction Of Solar Irradiance Using An Echo State Network, Stephen M. Ruffing, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

An Echo State Network (ESN) can make multi-step predictions since it can process temporal information without the training difficulties encountered by conventional recurrent neural networks. an ESN is applied in this paper to make multistep predictions of solar irradiance, 30 minutes to 270 minutes into the future. the ESN is trained and tested using two performance metrics (correlation coefficient and mean squared error) on meteorological and solar data recorded at the National Renewable Energy Laboratory Solar Radiation Research Laboratory in Golden, Colorado. When feedback of target outputs is utilized, an improvement is seen for the first performance metric, while no …

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Comparison Of Enhanced-Pso And Classical Optimization Methods: A Case Study For Statcom Placement, Yamille Del Valle, Ronald G. Harley, Ganesh K. Venayagamoorthy Dec 2009

Comparison Of Enhanced-Pso And Classical Optimization Methods: A Case Study For Statcom Placement, Yamille Del Valle, Ronald G. Harley, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

This paper validates the effectiveness of an enhanced particle swarm optimizer (Enhanced-PSO) method in solving the problem of optimal allocation of FACTS devices in a power system. the performance of the Enhanced-PSO method is compared with classical optimization approaches using a simple but realistic case study of optimal allocation of STATCOM devices, considering steady state and economic criteria. This paper also discusses the concepts and details about the optimization process that tend to be overlooked in the literature since the selection of an optimization algorithm highly depends on them. © 2009 IEEE.

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Heuristic Algorithms For Solving Convex And Nonconvex Economic Dispatch, Yusuf Yare, Ganesh K. Venayagamoorthy, Ahmed Yousuf Saber Dec 2009

Heuristic Algorithms For Solving Convex And Nonconvex Economic Dispatch, Yusuf Yare, Ganesh K. Venayagamoorthy, Ahmed Yousuf Saber

Electrical and Computer Engineering Faculty Research & Creative Works

Economic dispatch (ED) is a power system optimization problem, and its objective is to reduce the total generation cost of units while satisfying constraints. the presence of nonlinearities in practical generator operation makes solving the ED problem more challenging. These generator nonlinearities are modeled as constraints to be met in the form of ramp-rate limits and prohibited operating zones. This paper proposes three heuristic algorithms, namely, the genetic algorithm (GA), differential evolution (DE) and modified particle swarm optimization (MPSO) to solve this ED problem for two test systems. Simulation, numerical results and convergence performances of these three algorithms are presented …

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Performance Analysis Of Live-Virtual-Constructive And Distributed Virtual Simulations: Defining Requirements In Terms Of Temporal Consistency, Douglas D. Hodson Dec 2009

Performance Analysis Of Live-Virtual-Constructive And Distributed Virtual Simulations: Defining Requirements In Terms Of Temporal Consistency, Douglas D. Hodson

Theses and Dissertations

This research extends the knowledge of live-virtual-constructive (LVC) and distributed virtual simulations (DVS) through a detailed analysis and characterization of their underlying computing architecture. LVCs are characterized as a set of asynchronous simulation applications each serving as both producers and consumers of shared state data. In terms of data aging characteristics, LVCs are found to be first-order linear systems. System performance is quantified via two opposing factors; the consistency of the distributed state space, and the response time or interaction quality of the autonomous simulation applications. A framework is developed that defines temporal data consistency requirements such that the objectives …

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Electromagnetic Field Control And Optimization Using Metamaterials, Jeffrey S. Mcguirk Dec 2009

Electromagnetic Field Control And Optimization Using Metamaterials, Jeffrey S. Mcguirk

Theses and Dissertations

Transformation optics has shown the ability to cloak an object from incident electromagnetic radiation is possible. However, the material parameters are inhomogeneous, anisotropic, and, in some instances, singular at various locations. In order for a cloak to be practically realized, simplified parameter sets are required. However, the simplified parameters result in a degradation in the cloaking function. Constitutive parameters for simplified two-dimensional cylindrical cloaks have been developed with two material property constraints. It was initially believed satisfying these two constraints would result in the simplified cylindrical cloaks having the same wave equation as an ideal cloak. Because of this error, …

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A Physical Model Of Human Skin And Its Application For Search And Rescue, Abel S. Nunez Dec 2009

A Physical Model Of Human Skin And Its Application For Search And Rescue, Abel S. Nunez

Theses and Dissertations

For this research we created a human skin reflectance model in the VIS and NIR. We then modeled sensor output for an RGB sensor based on output from the skin reflectance model. The model was also used to create a skin detection algorithm and a skin pigmentation level (skin reflectance at 685nm) estimation algorithm. The average root mean square error across the VIS and NIR between the skin reflectance model and measured data was 2%. The skin reflectance model then allowed us to generate qualitatively accurate responses for an RGB sensor for different biological and lighting conditions. To test the …

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