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2011

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Articles 1501 - 1530 of 5801

Full-Text Articles in Engineering

Syntax Proposal For Nominal Schemas, David Carral Martinez, Adila A. Krisnadhi, Pascal Hitzler Jul 2011

Syntax Proposal For Nominal Schemas, David Carral Martinez, Adila A. Krisnadhi, Pascal Hitzler

Computer Science and Engineering Faculty Publications

This paper proposes a syntax representation for nominal schemas, a new description-logic style ex- tension of OWL 2 [2, 3]. Necessary and minimal modifications to Functional and Manchester grammars are included as well as mappings from these two syntaxes to Turtle. An appendix with two examples is added in order to clarify the proposal.


Development Of A Second-Stage Novice Driver Education And Training Program, John Wagner, M Jensen, F Switzer, K Alexander, P Pidgeon Jul 2011

Development Of A Second-Stage Novice Driver Education And Training Program, John Wagner, M Jensen, F Switzer, K Alexander, P Pidgeon

Publications

Novice drivers are overrepresented in traffic crashes and fatalities. Traffic crashes are the leading cause of death for 16 to 20 year olds and account for one in three deaths in this age group (NHTSA, 2008; CDC, 2010). Significant research has been conducted developing and analyzing driver education and training and education programs. Effective programs identify their target audiences and tailor the program paradigm and methods to their developmental needs. This paper develops a second-stage safe driver program for novice drivers focusing on classroom and behind-the-wheel instruction for four common driving skills and situations: braking, avoiding obstacles, losing control, and …


Electromagnetic Waves In Contaminated Soils, Arvin Farid, Akram N. Alshawabkeh, Carey M. Rappaport Jul 2011

Electromagnetic Waves In Contaminated Soils, Arvin Farid, Akram N. Alshawabkeh, Carey M. Rappaport

Civil Engineering Faculty Publications and Presentations

Soil is a complex, potentially heterogeneous, lossy, and dispersive medium. Modeling the propagation and scattering of electromagnetic (EM) waves in soil is, hence, more challenging than in air or in other less complex media. This chapter will explain fundamentals of the numerical modeling of EM wave propagation and scattering in soil through solving Maxwell’s equations using a finite difference time domain (FDTD) method. The chapter will explain how: (i) the lossy and dispersive soil medium (in both dry and fully water-saturated conditions), (ii) a fourth phase (anomaly), (iii) two different types of transmitting antennae (a monopole and a dipole), and …


Sensorimotor Control Of 3d Arm Movement And Stability In Post-Stroke Hemiparesis, Kakanand Alfonsomarie Srungboonmee Jul 2011

Sensorimotor Control Of 3d Arm Movement And Stability In Post-Stroke Hemiparesis, Kakanand Alfonsomarie Srungboonmee

Dissertations (1934 -)

Deficits of the affected arm in people with post-stroke hemiparesis have been generally associated with decreased strength and increased spasticity. These deficits are varied in proximal (shoulder) and distal (elbow) joints which results in an overall impairment during movement or during stabilization of hand position in space. In this study, reaching of the hemiparetic arm in 3D workspace was characterized by a curved and non-smooth endpoint trajectory and a reduced functional range of motion, compared to the unimpaired arm. Smoother trajectories were observed in the acceleration phase more than the deceleration phase, which was common to both the stroke subjects …


A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio Jul 2011

A Study On Facility Planning Using Discrete Event Simulation: Case Study Of A Grain Delivery Terminal, Sarah M. Asio

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

The application of traditional approaches to the design of efficient facilities can be tedious and time consuming when uncertainty and a number of constraints exist. Queuing models and mathematical programming techniques are not able to capture the complex interaction between resources, the environment and space constraints for dynamic stochastic processes. In the following study discrete event simulation is applied to the facility planning process for a grain delivery terminal. The discrete event simulation approach has been applied to studies such as capacity planning and facility layout for a gasoline station and evaluating the resource requirements for a manufacturing facility. To …


Modeling And Control For Heave Dynamics Of A Flexible Wing Micro Aerial Vehicle Distributed Parameter System, Lisa M. Kuhn Jul 2011

Modeling And Control For Heave Dynamics Of A Flexible Wing Micro Aerial Vehicle Distributed Parameter System, Lisa M. Kuhn

Doctoral Dissertations

In recent years, much research has been motivated by the idea of biologically-inspired flight. It is a conjecture of the United States Air Force that incorporating characteristics of biological flight into air vehicles will significantly improve the maneuverability and performance of modern aircraft. Although there are studies which involve the aerodynamics, structural dynamics, modeling, and control of flexible wing micro aerial vehicles (MAVs), issues of control and vehicular modeling as a whole are largely unexplored. Modeling with such dynamics lends itself to systems of partial differential equations (PDEs) with nonlinearities, and limited control theory is available for such systems.

In …


Nanofabrication Of Halloysite-Pcl Composite Scaffolds And Functionalization Of Titanium For Tissue Regeneration, Shraddha Parshottambhai Patel Jul 2011

Nanofabrication Of Halloysite-Pcl Composite Scaffolds And Functionalization Of Titanium For Tissue Regeneration, Shraddha Parshottambhai Patel

Doctoral Dissertations

Major medical needs may be achieved through regenerative medicine. Nanotechnology has triggered a research revolution in many important areas such as the biomedical sciences and bioengineering at the molecular level which has grown significantly due to the availability of new analytical applications and tools based on nanotechnology. Clinical conditions and diseases being targeted by nanotechnology research include burns, Alzheimer's and Parkinson's disease, implant failure, improved wound healing, birth defects, osteoporosis and congestive heart defects. Therapeutic use of growth factors and drugs to stimulate the production and/or function of endogenous cells represents a key area of regenerative medicine. The development of …


Design, Behavior, And Performance Of Precast Concrete Bridge Barriers, Walid Rajab Alaywan Jul 2011

Design, Behavior, And Performance Of Precast Concrete Bridge Barriers, Walid Rajab Alaywan

Doctoral Dissertations

The guidelines proposed by the NCHRP Report 350 pertaining to the safety of roadway hardware devices necessitated the evaluation of those devices. This study deals with the strength evaluation of precast concrete bridge railing.

A literature review was performed before the start of the study. Though many articles, reports, and publications were found regarding the testing of cast-in-place concrete barriers, such similar publications pertaining to precast concrete bridge railing were almost non-existent.

The theoretical work was performed using the yield line theory to predict the strength of the precast barrier. Though the theory was developed for cast-in-place barriers where the …


Maximum Likelihood Approach To Pointwise Estimation In Statistical Data Processing Under Interval Uncertainty, Nitaya Buntao, Sa-Aat Niwitpong, Vladik Kreinovich Jul 2011

Maximum Likelihood Approach To Pointwise Estimation In Statistical Data Processing Under Interval Uncertainty, Nitaya Buntao, Sa-Aat Niwitpong, Vladik Kreinovich

Departmental Technical Reports (CS)

Traditional statistical estimates C(x1, ..., xn) for different statistical characteristics (such as mean, variance, etc.) implicitly assume that we know the sample values x1, ..., xn exactly. In practice, the sample values Xi come from measurements and are, therefore, in general, different from the actual (unknown) values Xi of the corresponding quantities. Sometimes, we know the probabilities of different values of the measurement error ΔXi = Xi - xi, but often, the only information that we have about the measurement error is the upper bound Δi …


Remote Monitoring Of Bridges, Rajan Sen, Gray Mullins, Alberto Sagues, Julio Aguilar, Danny Winters Jul 2011

Remote Monitoring Of Bridges, Rajan Sen, Gray Mullins, Alberto Sagues, Julio Aguilar, Danny Winters

Civil and Environmental Engineering Faculty Publications

This report summarizes findings from a 24-month study in which the performance of cathodic protection systems for substructures of two interstate bridges was remotely monitored. The two bridges #860050 and #860054 are located on the “Alligator Alley” toll portion of eastbound I-75 in Broward County, FL. Each bridge spans two pilesupported piers inside a drainage canal. The seven steel H-piles supporting the piers are jacketed in concrete to a level just below the water surface and are cathodically protected by three magnesium anodes spaced uniformly over their submerged length.


Astro Camp Presentation, Get Away Special Team 2011 Jul 2011

Astro Camp Presentation, Get Away Special Team 2011

Education and Outreach

No abstract provided.


Social Innovation Concepts At Nasa: Integrating International Development Challenges And Hands-On Prototyping With Spacecraft Design Training, Leonard Yowell, Evan A. Thomas Jul 2011

Social Innovation Concepts At Nasa: Integrating International Development Challenges And Hands-On Prototyping With Spacecraft Design Training, Leonard Yowell, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

The NASA Johnson Space Center Social Innovation program has been designed to encourage innovation within the NASA community that benefits both NASA's core mission as well as human needs domestically and internationally. By encouraging internal and external collaboration and providing resources including the new Johnson Space Center "Sandbox" design shop, new innovations are anticipated. Technologies developed for the human exploration of space share similar requirements with appropriate technology for the developing world. The technology goals of keeping people alive in a difficult environment involve addressing requirements for low maintenance and robustness and often include using renewable energy sources. Technologies developed …


Electric Breakdown Of Longitudinally Shocked Pb(Zr₀.₅₂Ti₀.₄₈)O₃ Ceramics, S. I. Shkuratov, E. F. Talantsev, Jason Baird Jul 2011

Electric Breakdown Of Longitudinally Shocked Pb(Zr₀.₅₂Ti₀.₄₈)O₃ Ceramics, S. I. Shkuratov, E. F. Talantsev, Jason Baird

Mining Engineering Faculty Research & Creative Works

Electric breakdown of longitudinally-shock-compressed Pb(Zr₀.₅₂Ti₀.₄₈)O₃ (PZT 52/48) ferroelectric ceramics was experimentally investigated. It was found that a dependence of breakdown field strength, Eg, of shocked ferroelectrics on the thickness of the element, d, ranging from 0.65 to 6.5 mm is described by the Eg (d) = γ  · d-w law that describes the breakdown of dielectrics at ambient conditions. It follows from the experimental results that the tunnel effect is a dominant mechanism of injection of prime electrons in the shocked ferroelectric elements. It was demonstrated that electric breakdown causes significant energy losses in miniature autonomous …


Nitrogen Mass Balance In A High Rate Algal Pond, Kevin Jones Jul 2011

Nitrogen Mass Balance In A High Rate Algal Pond, Kevin Jones

Biomedical Engineering

The objective of the study described herein was to perform a mass balance on nitrogen in four small high rate algal ponds (HRAPs) in order to determine the fate of the nitrogen. The total percentage of nitrogen lost via ammonia volatilization was calculated via the mass balance.


Direct Simulation Monte Carlo Study Of Effects Of Thermal Nonuniformities In Electron-Beam Physical Vapor Deposition, A. Venkattraman, Alina A. Alexeenko Jul 2011

Direct Simulation Monte Carlo Study Of Effects Of Thermal Nonuniformities In Electron-Beam Physical Vapor Deposition, A. Venkattraman, Alina A. Alexeenko

Birck and NCN Publications

In a typical electron-beam physical vapor deposition system, there is limited control over how the high-power electron beam heats the metal surface. This leads to thermal nonuniformities at the melt. Three-dimensional direct simulation Monte Carlo simulations were performed with the aim of quantifying the effect of such spatial variations of source temperature in thin film depositions using an electron-beam physical vapor deposition system. The source temperature distribution from a typical deposition process was used in the direct simulation Monte Carlo simulations performed for various mass flow rates. The use of an area-averaged temperature is insufficient for all mass flow rates …


Schottky-Barrier Height Modulation Of Metal/In0.53ga0.47as Interfaces By Insertion Of Atomic-Layer Deposited Ultrathin Al2o3, Runsheng Wang, Min Xu, Peide D. Ye, Ru Huang Jul 2011

Schottky-Barrier Height Modulation Of Metal/In0.53ga0.47as Interfaces By Insertion Of Atomic-Layer Deposited Ultrathin Al2o3, Runsheng Wang, Min Xu, Peide D. Ye, Ru Huang

Birck and NCN Publications

The improvement of the metal/InGaAs interface is essential for the future application of InGaAs metal source/drain Schottky-barrier metal-oxide-semiconductor field-effect-transistors. In this article, on In0.53Ga0.47As, the authors examine the recently proposed method of inserting an ultrathin insulator to modulate the effective Schottky-barrier height (SBH) at the metal/semiconductor interface. Both n-type and p-type In0.53Ga0.47As are investigated by inserting an atomic-layer deposited Al2O3 interlayer. The results indicate that SBH modulation is more effective at the n-InGaAs interface than the p-InGaAs interface for the same Al2O3 thickness. However, the Fermi level at the metal/InGaAs interface is still weakly pinned even after inserting 2 nm …


Numerical Modeling Of Plasmonic Nanoantennas With Realistic 3d Roughness And Distortion, Alexander V. Kildishev, Joshua D. Borneman, Kuo-Ping Chen, Vladimir P. Drachev Jul 2011

Numerical Modeling Of Plasmonic Nanoantennas With Realistic 3d Roughness And Distortion, Alexander V. Kildishev, Joshua D. Borneman, Kuo-Ping Chen, Vladimir P. Drachev

Birck and NCN Publications

Nanostructured plasmonic metamaterials, including optical nanoantenna arrays, are important for advanced optical sensing and imaging applications including surface-enhanced fluorescence, chemiluminescence, and Raman scattering. Although designs typically use ideally smooth geometries, realistic nanoantennas have nonzero roughness, which typically results in a modified enhancement factor that should be involved in their design. Herein we aim to treat roughness by introducing a realistic roughened geometry into the finite element (FE) model. Even if the roughness does not result in significant loss, it does result in a spectral shift and inhomogeneous broadening of the resonance, which could be critical when fitting the FE simulations …


A Deterministic Method Of Predicting Long-Term Pile Capacity In Cohesive Soils After The Dissipation Of Excess Pore Water Pressure, Eric J. Steward Jul 2011

A Deterministic Method Of Predicting Long-Term Pile Capacity In Cohesive Soils After The Dissipation Of Excess Pore Water Pressure, Eric J. Steward

Doctoral Dissertations

Pile setup or freeze is a phenomenon where the bearing capacity of a pile increases over time both during and after the dissipation of pore pressure and the stabilization of lateral earth pressure. Driven piles gain capacity after installation because of the dissipation of excess pore pressure and soil aging. Incorporating accurate setup prediction into the design of the piles can significantly reduce the cost of many projects by reducing the size or number of required piles. Various simple, empirical mathematical models have been developed to predict pile setup. However, these models are often unreliable, resulting in very conservative designs. …


Predicting Deterioration Rate Of Culvert Structures Utilizing A Markov Model, Chenguang Yang Jul 2011

Predicting Deterioration Rate Of Culvert Structures Utilizing A Markov Model, Chenguang Yang

Doctoral Dissertations

A culvert is typically a hydraulic passage, normally placed perpendicular to the road alignment, which connects the upstream and downstream sections underneath an embankment, while also providing structural support for earth and traffic loads. The structural condition of culverts continues to deteriorate due to aging, limited maintenance budgets, and increased traffic loads. Maintaining the performance of culverts at acceptable levels is a priority for the U.S. Department of Transportation (DOT), and an effective maintenance of culvert structures can be greatly improved by introducing asset management practices. A priority list generated by traditional condition assessment might not provide optimum solutions, and …


Using A Systemic Model Of Accident For Improving Innovative Technologies: Application And Limitations Of The Stamp Model To A Process For Treatment Of Contaminated Substances, Karim Hardy, Franck Guarnieri Jul 2011

Using A Systemic Model Of Accident For Improving Innovative Technologies: Application And Limitations Of The Stamp Model To A Process For Treatment Of Contaminated Substances, Karim Hardy, Franck Guarnieri

Publications

This paper presents the STAMP accident model, based on systems theory, and describes its application in the context of risk prevention related to the remediation of contaminated materials. The implementation of the model is described, and results are presented both in methodological and technical terms.


Finding Robust-Under-Risk Solutions For Flowshop Scheduling, Steven O. Kimbrough, Ann Kuo, Hoong Chuin Lau Jul 2011

Finding Robust-Under-Risk Solutions For Flowshop Scheduling, Steven O. Kimbrough, Ann Kuo, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

We propose and explore, in the context of benchmark problems for flowshop scheduling, a risk-based concept of robustness for optimization problems. This risk-based concept is in distinction to, and complements, the uncertainty-based concept employed in the field known as robust optimization. Implementation of our concept requires problem solution methods that sample the solution space intelligently and that produce large numbers of distinct sample points. With these solutions to hand, their robustness scores are easily obtained and heuristically robust solutions found. We find evolutionary computation to be effective for this purpose on these problems.


Using Modeling And Simulation To Improve Oral Health Services Delivery In Hampton Roads, Virginia, Mohammad J. Alzahrani Jul 2011

Using Modeling And Simulation To Improve Oral Health Services Delivery In Hampton Roads, Virginia, Mohammad J. Alzahrani

Health Services Research Dissertations

The purpose of this study is to examine the system performance in delivering oral health services in a public health district based on the Conceptual Framework to Measure Performance of the Public Health System (PHS). Using modeling and simulation, a predictive model based on the conceptual framework dimensions: mission, structural capacity, processes, and outcomes was developed to predict the performance of public health district in delivering oral health services.

This is a retrospective longitudinal study. The main objective of this study is to use a modeling and simulation approach to predict the performance of public health district dental clinic in …


Automatic High-Fidelity 3d Road Network Modeling, Jie Wang Jul 2011

Automatic High-Fidelity 3d Road Network Modeling, Jie Wang

Computational Modeling & Simulation Engineering Theses & Dissertations

Many computer applications such as racing games and driving simulations frequently make use of 3D high-fidelity road network models for a variety of purposes. However, there are very few existing methods for automatic generation of 3D realistic road networks, especially for those in the real world. On the other hand, vast road network GIS data have been collected in the past and used by a wide range of applications, such as navigation and evaluation. A method that can automatically produce 3D high-fidelity road network models from 2D real road GIS data will significantly reduce both the labor and time needed …


Statistical Optimizations Of Muscle Action Potentials Based On Modeling And Analysis Of Ion Channel Dynamics, Gyutae Kim Jul 2011

Statistical Optimizations Of Muscle Action Potentials Based On Modeling And Analysis Of Ion Channel Dynamics, Gyutae Kim

Electrical & Computer Engineering Theses & Dissertations

An Electromyogram (EMG) is an electrical signal, which is measured from a skeletal muscle during voluntary and involuntary contractions. EMGs are useful in interpreting pathological states of the musculoskeletal system. In particular, EMGs offer valuable information concerning the timing of muscular activity and its relative intensity. Various EMG models have developed with many different purposes from a pure mathematical model to a pattern structure model [17,46]. Sophisticated EMG models are necessary to examine the effects of small changes in muscular morphology and activities [46]. Due to the crucial importance of EMG models, all factors in the model should be precise …


The Tracking Performance Of Distributed Recoverable Flight Control Systems Subject To High Intensity Radiated Fields, Rui Wang Jul 2011

The Tracking Performance Of Distributed Recoverable Flight Control Systems Subject To High Intensity Radiated Fields, Rui Wang

Electrical & Computer Engineering Theses & Dissertations

It is known that high intensity radiated fields (HIRF) can produce upsets in digital electronics, and thereby degrade the performance of digital flight control systems. Such upsets, either from natural or man-made sources, can change data values on digital buses and memory and affect CPU instruction execution. HIRF environments are also known to trigger common-mode faults, affecting nearly-simultaneously multiple fault containment regions, and hence reducing the benefits of n-modular redundancy and other fault-tolerant computing techniques. Thus, it is important to develop models which describe the integration of the embedded digital system, where the control law is implemented, as well …


Perfectly Matched Layer Absorbing Boundary Conditions For The Discrete Velocity Boltzmann-Bgk Equation, Elena Craig Jul 2011

Perfectly Matched Layer Absorbing Boundary Conditions For The Discrete Velocity Boltzmann-Bgk Equation, Elena Craig

Mathematics & Statistics Theses & Dissertations

Perfectly Matched Layer (PML) absorbing boundary conditions were first proposed by Berenger in 1994 for the Maxwell's equations of electromagnetics. Since Hu first applied the method to Euler's equations in 1996, progress made in the application of PML to Computational Aeroacoustics (CAA) includes linearized Euler equations with non-uniform mean flow, non-linear Euler equations, flows with an arbitrary mean flow direction, and non-linear clavier-Stokes equations. Although Boltzmann-BGK methods have appeared in the literature and have been shown capable of simulating aeroacoustics phenomena, very little has been done to develop absorbing boundary conditions for these methods. The purpose of this work was …


A Systemic Approach To Next Generation Infrastructure Data Elicitation And Planning Using Serious Gaming Methods, Ersin Ancel Jul 2011

A Systemic Approach To Next Generation Infrastructure Data Elicitation And Planning Using Serious Gaming Methods, Ersin Ancel

Engineering Management & Systems Engineering Theses & Dissertations

Infrastructure systems are vital to the functioning of our society and economy. However, these systems are increasingly complex and are more interdependent than ever, making them difficult to manage. In order to respond to increasing demand, environmental concerns, and natural and man-made threats, infrastructure systems have to adapt and transform. Traditional engineering design approaches and planning tools have proven to be inadequate when planning and managing these complex socio-technical system transitions. The design and implementation of next generation infrastructure systems require holistic methodologies, encompassing organizational and societal aspects in addition to technical factors. In order to do so, a serious …


Ultrafast Electron Diffraction Study Of The Dynamics Of Antimony Thin Films And Nanoparticles, Mahmoud Abdel-Fattah Jul 2011

Ultrafast Electron Diffraction Study Of The Dynamics Of Antimony Thin Films And Nanoparticles, Mahmoud Abdel-Fattah

Electrical & Computer Engineering Theses & Dissertations

The ultrafast fast phenomena that take place following the application of a 120 fs laser pulse on 20 nm antimony thin films and 40 nm nanoparticles were studied using time-resolved electron diffraction. Samples are prepared by thermal evaporation, at small thickness (< 10 nm) antimony nanoparticles form while at larger thicknesses we get continuous thin films.

The samples are annealed and studied by static heating to determine their Debye temperatures, which were considerably less than the standard value. The thermal expansion under static heating also yielded the expansion coefficient of the sample material. Nanoparticle samples gave a very accurate thermal expansion coefficient (11 × 10-6 K-1).

Ultrafast time resolved electron diffraction …


Improving The Efficiency Of Organic Solar Cells By Varying The Material Concentration In The Photoactive Layer, Kevin Anthony Latimer Jul 2011

Improving The Efficiency Of Organic Solar Cells By Varying The Material Concentration In The Photoactive Layer, Kevin Anthony Latimer

Electrical & Computer Engineering Theses & Dissertations

Polymer-fullerene bulk heterojunction solar cells have been a rapidly improving technology over the past decade. To further improve the relatively low energy conversion efficiencies of these solar cells, several modifications need to be made to the overall device structure. Emerging technologies include cells that are fabricated with interfacial layers to facilitate charge transport, and tandem structures are being introduced to harness the absorption spectrum of polymers with varying bandgap energies.

When new structures are implemented, each layer of the cell must be optimized in order for the entire device to function efficiently. The most volatile layer of these devices is …


Cyberknife Radiation Modeling: Effects Of Relaxed Translational And Rotational Constraints On Healthy Tissue Irradiation, Sudha Bhavaroop Potineni Jul 2011

Cyberknife Radiation Modeling: Effects Of Relaxed Translational And Rotational Constraints On Healthy Tissue Irradiation, Sudha Bhavaroop Potineni

Electrical & Computer Engineering Theses & Dissertations

The Cyberknife system is a robotic radio surgery instrument that is used to treat cancers in different parts of the human body. Because of its accuracy and precision, it has become one of the best radio surgery systems in the world. However, even with Cyberknife the treatment time for one session takes from 30 minutes up to 120 minutes depending on the size, shape, and position of the tumor in the human body. In this research, a solution is presented to aid in reducing this long treatment time. An algorithm is developed which simulates the amount of the healthy tissue …