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Articles 31 - 60 of 125
Full-Text Articles in Engineering
Autonomous Robotic Automation Systemwith Vision Feedback, Jeffery Rosino
Autonomous Robotic Automation Systemwith Vision Feedback, Jeffery Rosino
Electronic Theses and Dissertations
In this thesis, a full design, development and application of an autonomous robotic automation system using vision feedback is performed. To realize this system, a cylindrical manipulator configuration is implemented, using a personal computer (PC) based PID controller from National Instruments. Full autonomous control will be achieved via a programmable human machine interface (HMI) developed on a PC using Borland C++ Builder. The vision feedback position control is accomplished using an ordinary "off-the-shelf" web camera. The manuscript is organized as follows; After Chapter 1, an introduction to automation history and its role in the manufacturing industry, Chapter 2 discusses and …
The Removal Of Motion Artifacts From Non-Invasive Blood Pressure Measurements, Paresh Thakkar
The Removal Of Motion Artifacts From Non-Invasive Blood Pressure Measurements, Paresh Thakkar
Electronic Theses and Dissertations
Modern Automatic Blood Pressure Measurement Techniques are based on measuring the cuff pressure and on sensing the pulsatile amplitude variations. These measurements are very sensitive to motion of the patient or the surroundings where the patient is. The slightest unexpected movements could offset the readings of the automatic Blood Pressure meter by a large amount or render the readings totally meaningless. Every effort must be taken to avoid subjecting the body of the patient or the patient's surroundings to motion for obtaining a reliable reading. But there are situations in which we need Blood Pressure Measurements with the patient or …
Data Transmission Scheduling For Distributed Simulation Using Packet A, Juan Vargas-Morales
Data Transmission Scheduling For Distributed Simulation Using Packet A, Juan Vargas-Morales
Electronic Theses and Dissertations
Communication bandwidth and latency reduction techniques are developed for Distributed Interactive Simulation (DIS) protocols. Using logs from vignettes simulated by the OneSAF Testbed Baseline (OTB), a discrete event simulator based on the OMNeT++ modeling environment is developed to analyze the Protocol Data Unit (PDU) traffic over a wireless flying Local Area Network (LAN). Alternative PDU bundling and compression techniques are studied under various metrics including slack time, travel time, queue length, and collision rate. Based on these results, Packet Alloying, a technique for the optimized bundling of packets, is proposed and evaluated. Packet Alloying becomes more active when it is …
Sinbad Automation Of Scientific Process: From Hidden Factor Analysis To Theory Synthesis, Olcay Kursun
Sinbad Automation Of Scientific Process: From Hidden Factor Analysis To Theory Synthesis, Olcay Kursun
Electronic Theses and Dissertations
Modern science is turning to progressively more complex and data-rich subjects, which challenges the existing methods of data analysis and interpretation. Consequently, there is a pressing need for development of ever more powerful methods of extracting order from complex data and for automation of all steps of the scientific process. Virtual Scientist is a set of computational procedures that automate the method of inductive inference to derive a theory from observational data dominated by nonlinear regularities. The procedures utilize SINBAD – a novel computational method of nonlinear factor analysis that is based on the principle of maximization of mutual information …
Nitrification Investigation And Modeling In The Chloraminated Drinking Water Distribution System, Suibing Liu
Nitrification Investigation And Modeling In The Chloraminated Drinking Water Distribution System, Suibing Liu
Electronic Theses and Dissertations
This dissertation consists of five papers concerning nitrification in chloraminated drinking water distribution systems in a one and a half year field study. Seven finished waters were produced from different treatment processes and distributed to eighteen pilot distribution systems (PDSs) that were made pipes taken from actual distribution systems. Unlined cast iron (UCI), galvanized steel (G), lined cast iron (LCI), and PVC pipes were used to build the PDSs. All finished waters were stabilized and chloraminated before entering the PDSs. This dissertation consists of five major parts. (1) System variations of nitrates, nitrites, DO, pH, alkalinity, temperature, chloramine residuals and …
Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat
Multiple Scattering Of Light In Inhomogeneous Media And Applications, Claudia Mujat
Electronic Theses and Dissertations
Light scattering-based techniques are being developed for non-invasive diagnostics of inhomogeneous media in various fields, such as medicine, biology, and material characterization. However, as most media of interest are highly scattering and have a complex structure, it is difficult to obtain a full analytical solution of the scattering problem without introducing approximations and assumptions about the properties of the system under consideration. Moreover, most of the previous studies deal with idealized scattering situations, rarely encountered in practice. This dissertation provides new analytical, numerical, and experimental solutions to describe subtle effects introduced by the properties of the light sources, and by …
Polarimetric Characterization Of Random Electromagnetic Beams And Applications, Mircea Mujat
Polarimetric Characterization Of Random Electromagnetic Beams And Applications, Mircea Mujat
Electronic Theses and Dissertations
Polarimetry is one of the principal means of investigating the interaction of light with matter. Theoretical models and experimental techniques are presented in this dissertation for polarimetric characterization of random electromagnetic beams and of signatures of random media in different scattering regimes and configurations. The degree of polarization rather than the full description of the state of polarization is of interest in multiple scattering and free space propagation where the statistical nature and not the deterministic component of light bears the relevant information. A new interferometric technique for determining the degree of polarization by measuring the intensity fluctuations in a …
Optimal Upfc Control And Operations For Power Systems, Xiaohe Wu
Optimal Upfc Control And Operations For Power Systems, Xiaohe Wu
Electronic Theses and Dissertations
The content of this dissertation consists of three parts. In the first part, optimal control strategies are developed for Unified Power Flow Controller (UPFC) following the clearance of fault conditions. UPFC is one of the most versatile Flexible AC Transmission devices (FACTs) that have been implemented thus far. The optimal control scheme is composed of two parts. The first is an optimal stabilization control, which is an open-loop ‘Bang’ type of control. The second is an suboptimal damping control, which consists of segments of ‘Bang’ type control with switching functions the same as those of a corresponding approximate linear system. …
Non-Destructive Microstructural Evaluation Of Yttria Stabilized Zirconia, Nickel Aluminides And Thermal Barrier Coatings Using Electrochemical Impedance Spectroscopy, Srinivas Vishweswaraiah
Non-Destructive Microstructural Evaluation Of Yttria Stabilized Zirconia, Nickel Aluminides And Thermal Barrier Coatings Using Electrochemical Impedance Spectroscopy, Srinivas Vishweswaraiah
Electronic Theses and Dissertations
There has been an urge for increasing the efficiency in advanced gas turbine engines. To fulfill these needs the inlet gas temperatures should be increased in the gas turbine engines, thermal barrier coatings (TBCs) have gained significant applications in increasing the gas inlet temperatures. Insulating characteristics of ceramic TBCs allow the operation at up to 150~250 ˚C higher gas temperatures. Because of the severe turbine engine operating conditions that include high temperature, steep temperature gradient, thermal cycling, oxidation and hot-corrosion, TBCs can fail by spallation at the interface between the metal and ceramic. The lack of understanding in failure mechanisms …
Modeling Of Membrane Solute Mass Transfer In Ro/Nf Membrane Systems, Yu Zhao
Modeling Of Membrane Solute Mass Transfer In Ro/Nf Membrane Systems, Yu Zhao
Electronic Theses and Dissertations
Five articles describing the impact of surface characteristics, and development of mass transfer models for diffusion controlled membrane applications are published in this dissertation. Article 1 (Chapter 3) describes the impact of membrane surface characteristics and NOM on membrane performance for varying pretreatment and membranes during a field study. Surface charge, hydrophobicity and roughness varied significantly among the four membranes used in the study. Membrane surface characteristics, NOM and SUVA measurements were used to describe mass transfer in a low pressure RO integrated membrane system. Inorganic and organic solute and water mass transfer coefficients were systematically investigated for dependence on …
Sub-Optimal Ultra-Wide Band Receivers, Nilesh Bhuvanendran
Sub-Optimal Ultra-Wide Band Receivers, Nilesh Bhuvanendran
Electronic Theses and Dissertations
Ultra-wide Band (UWB) has sparked a lot of interest lately from the industry and academia. The growing capacity of the wireless industry is requires a new communication system that satisfies the high data rate which does not interfere with existing RF systems. UWB promises to be this new technology. UWB also promises low power, low cost and flexibility. The UWB Channel opens up a huge new wireless channel with Giga Hertz Capacities as well as the highest spatial capacities measured in bits per hertz per square meter. When properly implemented UWB channel can share spectrum with traditional radio systems without …
Nascar Restrictor Plate Exhaust Manifold Design Strategies, Matthew John Dollhopf
Nascar Restrictor Plate Exhaust Manifold Design Strategies, Matthew John Dollhopf
Electronic Theses and Dissertations
This paper presents the results of a study on exhaust manifold design for a NASCAR Restrictor plate internal combustion engine. A computer simulation model was developed using Ricardo WAVE software. WAVE is a computer-aided engineering code developed by Ricardo to analyze the dynamics of pressure waves, mass flows and energy losses in ducts, plenums and the intake and exhaust manifolds of various systems and machines. [1] The model was validated against experimental data from a current NASCAR Winston Cup restrictor plate motor. The parameters studied have been exhaust manifold diameters and lengths. A response surface analysis of the simulation output …
Surface Chemistry Of Application Specific Pads And Copper Chemical Mechanical Planarization, Sameer Arun Deshpande
Surface Chemistry Of Application Specific Pads And Copper Chemical Mechanical Planarization, Sameer Arun Deshpande
Electronic Theses and Dissertations
Advances in the interconnection technology have played a key role in the continued improvement of the integrated circuit (IC) density, performance and cost. Copper (Cu) metallization, dual damascenes processing and integration of copper with low dielectric constant material are key issues in the IC industries. Chemical mechanical planarization of copper (CuCMP) has emerged as an important process for the manufacturing of ICs. Usually, Cu-CMP process consists of several steps such as the removal of surface layer by mechanical action of the pad and the abrasive particles, the dissolution of the abraded particles in the CMP solution, and the protection of …
Processing, Microstructural And Mechanical Characterization Of Mechanically Alloyed Al-Al2o3 Nanocomposites, Pushkar Katiyar
Processing, Microstructural And Mechanical Characterization Of Mechanically Alloyed Al-Al2o3 Nanocomposites, Pushkar Katiyar
Electronic Theses and Dissertations
Aluminum-alumina nanocomposites were synthesized using mechanical alloying of blended component powders of pure constituents. This study was performed on various powder mixtures with aluminum as the matrix and alumina as the reinforcement with volume fractions of 20, 30, and 50 % and Al2O3 particle sizes of 50 nm, 150 nm, and 5 µm. X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques were used for the crystal structure and microstructural characterization of the powders at different stages of milling. Al2O3 powders with 50 nm and 150 nm particle size were predominantly of γ-type, while Al2O3 of 5 µm size was …
Quadratic Spatial Soliton Interactions, Ladislav Jankovic
Quadratic Spatial Soliton Interactions, Ladislav Jankovic
Electronic Theses and Dissertations
Quadratic spatial soliton interactions were investigated in this Dissertation. The first part deals with characterizing the principal features of multi-soliton generation and soliton self-reflection. The second deals with two beam processes leading to soliton interactions and collisions. These subjects were investigated both theoretically and experimentally. The experiments were performed by using potassium niobate (KNBO3) and periodically poled potassium titanyl phosphate (KTP) crystals. These particular crystals were desirable for these experiments because of their large nonlinear coefficients and, more importantly, because the experiments could be performed under non-critical-phase-matching (NCPM) conditions. The single soliton generation measurements, performed on KNBO3 by launching the …
Ocr: A Statistical Model Of Multi-Engine Ocr Systems, Mercedes Terre Mcdonald
Ocr: A Statistical Model Of Multi-Engine Ocr Systems, Mercedes Terre Mcdonald
Electronic Theses and Dissertations
This thesis is a benchmark performed on three commercial Optical Character Recognition (OCR) engines. The purpose of this benchmark is to characterize the performance of the OCR engines with emphasis on the correlation of errors between each engine. The benchmarks are performed for the evaluation of the effect of a multi-OCR system employing a voting scheme to increase overall recognition accuracy. This is desirable since currently OCR systems are still unable to recognize characters with 100% accuracy. The existing error rates of OCR engines pose a major problem for applications where a single error can possibly effect significant outcomes, such …
Nonlinear Adaptive Estimation Andits Application To Synchronization Of Lorenz System, Yufang Jin
Nonlinear Adaptive Estimation Andits Application To Synchronization Of Lorenz System, Yufang Jin
Electronic Theses and Dissertations
Synchronization and estimation of unknown constant parameters for Lorenz-type transmitter are studied under the assumption that one of the three state variables is not transmitted and that transmitter parameters are not known apriori. An adaptive algorithm is proposed to estimate both the state and system parameters. Since Lorenz system shows the property of sensitivity to initial conditions and evolves in different mode with parameter variation, an equivalent system is introduced. The adaptive observer is designed based on this equivalent system without any requirement on initial conditions of the observer. It is shown by Lyapunov arguments and persistent excitation analysis that …
Slurry Chemistry Effects On Copper Chemical Mechanical Planarization, Ying Luo
Slurry Chemistry Effects On Copper Chemical Mechanical Planarization, Ying Luo
Electronic Theses and Dissertations
Chemical-mechanical Planarization (CMP) has emerged as one of the fastest-growing processes in the semiconductor manufacturing industry, and it is expected to show equally explosive growth in the future (Braun, 2001). The development of CMP has been fueled by the introduction of copper interconnects in microelectronic devices. Other novel applications of CMP include the fabrications of microelectromechanical systems (MEMS), advanced displays, three dimensional systems, and so on (Evans, 2002). CMP is expected to play a key role in the next-generation micro- and nanofabrication technologies (Singh, et al., 2002). Despite the rapid increase in CMP applications, the fundamental understanding of the CMP …
Stable Spatial Solitons In Semiconductor Optical Amplifiers, Erdem Ultanir
Stable Spatial Solitons In Semiconductor Optical Amplifiers, Erdem Ultanir
Electronic Theses and Dissertations
A spatial soliton is a shape invariant self guided beam of light or a self induced waveguide. Spatial solitons appear as a result of the balance of diffraction and nonlinear focusing in a system. They have been observed in many different conservative media in the last couple of years. Solitons are ubiquitous, because of the probability of using their interactions in optical data processing, communications etc. Up to now due to the power required to generate the solitons, and the response times of the soliton supporting media, these special waves of nature could not penetrate the applications arena. Semiconductors, with …
Planar Magnetics Design For Low-Voltage Dc-Dc Converters, Shangyang Xiao
Planar Magnetics Design For Low-Voltage Dc-Dc Converters, Shangyang Xiao
Electronic Theses and Dissertations
The objectives of this thesis are to design planar magnetic devices based on accurate electromagnetic analysis and miniaturize magnetics within desired low profile as well as small footprint. A novel methodology based on FEM simulation is proposed. By introducing Maxwell 2D simulator, optimal interleaving structures can be found to reduce AC losses that cannot otherwise be accounted for by conventional method. And 3D simulator is employed to make the results more realistic. Thus, high-efficiency high-power density magnetics is achieved.
Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz
Object Tracking And Activity Recognition In Video Acquired Using Mobile Cameras, Alper Yilmaz
Electronic Theses and Dissertations
Due to increasing demand on deployable surveillance systems in recent years, object tracking and activity recognition are receiving considerable attention in the research community. This thesis contributes to both the tracking and the activity recognition components of a surveillance system. In particular, for the tracking component, we propose two different approaches for tracking objects in video acquired by mobile cameras, each of which uses a different object shape representation. The first approach tracks the centroids of the objects in Forward Looking Infrared Imagery (FLIR) and is suitable for tracking objects that appear small in airborne video. The second approach tracks …
Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication, Maha Abdelmoneim Mohamed Ali
Design And Analysis Of Adaptive And Reconfigurable Antennas For Wireless Communication, Maha Abdelmoneim Mohamed Ali
Electronic Theses and Dissertations
Modern radar and communication systems have experienced a tremendous increase in the number of antennas onboard, on the ground, and in orbital space. This places a burden due to the confined volume and limited weight requirements especially in space applications. The reconfigurable antenna is a promising and exciting new type of antenna, where through the use of appropriate switches the antenna can be structurally reconfigured, to maintain the elements near their resonant dimensions for several frequency bands. This increases the bandwidth of the antenna dramatically, which enables the use of one antenna for several applications. Four novel reconfigurable antenna elements …
Damage Modeling Method For Turbine Compressor Blade Tuning, Gennadiy Afanasiev
Damage Modeling Method For Turbine Compressor Blade Tuning, Gennadiy Afanasiev
Electronic Theses and Dissertations
The thesis presents a method of evaluation for blade damage in Combustion Turbine Compressor Section. This method involves use of multiple domains within a single Finite Element Model to predict the effect of damage on the blade properties. This approach offers significant time and effort savings when compared to traditional evaluation methods of similar problems. It is demonstrated via examples that the multi-domain modeling approach yields acceptable accuracy results. The economical implications of described method are readily applicable to both the industrial and the aerospace Combustion Turbine fields. It is economically impractical to replace the blade at each damage occurrence. …
Fast Algorithms For Fragment Based Completion In Images Of Natural Scenes, Siddharth Rajkumar Borikar
Fast Algorithms For Fragment Based Completion In Images Of Natural Scenes, Siddharth Rajkumar Borikar
Electronic Theses and Dissertations
Textures are used widely in computer graphics to represent fine visual details and produce realistic looking images. Often it is necessary to remove some foreground object from the scene. Removal of the portion creates one or more holes in the texture image. These holes need to be filled to complete the image. Various methods like clone brush strokes and compositing processes are used to carry out this completion. User skill is required in such methods. Texture synthesis can also be used to complete regions where the texture is stationary or structured. Reconstructing methods can be used to fill in large-scale …
Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua
Application Of Absorptive Treatments On Traffic Noise Barriers In Florida, Chin Boon Chua
Electronic Theses and Dissertations
In this thesis, the parallel barrier analysis feature in the Federal Highway Administration Traffic Noise Model (FHWA TNM), which is based on RAYVERB was used to explore the effects of multiple reflections due to single and parallel barriers and the use of absorptive treatment. Database was developed from the data collected from previous research efforts was used to generate a best fit equation model that can be used as a predetermining tool to determine the magnitude of parallel barrier insertion loss. The best fit equation model was then used to test against measured/model result and TNM prediction results for its …
Comparison Of Square-Hole And Round-Hole Film Cooling: A Computational Study, Michael Glenn Durham
Comparison Of Square-Hole And Round-Hole Film Cooling: A Computational Study, Michael Glenn Durham
Electronic Theses and Dissertations
Film cooling is a method used to protect surfaces exposed to high-temperature flows such as those that exist in gas turbines. It involves the injection of secondary fluid (at a lower temperature than that of the main flow) that covers the surface to be protected. This injection is through holes that can have various shapes; simple shapes such as those with a straight circular (by drilling) or straight square (by EDM) cross-section are relatively easy and inexpensive to create. Immediately downstream of the exit of a film cooling hole, a so-called horseshoe vortex structure consisting of a pair of counter-rotating …
Evolving Models From Observed Human Performance, Hans Karl Gustav Fernlund
Evolving Models From Observed Human Performance, Hans Karl Gustav Fernlund
Electronic Theses and Dissertations
To create a realistic environment, many simulations require simulated agents with human behavior patterns. Manually creating such agents with realistic behavior is often a tedious and time-consuming task. This dissertation describes a new approach that automatically builds human behavior models for simulated agents by observing human performance. The research described in this dissertation synergistically combines Context-Based Reasoning, a paradigm especially developed to model tactical human performance within simulated agents, with Genetic Programming, a machine learning algorithm to construct the behavior knowledge in accordance to the paradigm. This synergistic combination of well-documented AI methodologies has resulted in a new algorithm that …
Phenomenology And Experimental Observations In High Temperature Ternary Interdiffusion, Abby Lee Elliott
Phenomenology And Experimental Observations In High Temperature Ternary Interdiffusion, Abby Lee Elliott
Electronic Theses and Dissertations
A new method to extract composition dependent ternary interdiffusion coefficients from a single diffusion couple experiment is presented. The calculations involve direct determination of interdiffusion fluxes from experimental concentration profiles and local integration and differentiation of Onsager's formalism. This new technique was applied to concentration profiles obtained from selected semi-infinite, single-phase diffusion couple experiments in the Cu-Ni-Zn, Fe-Ni-Al, and Ni-Cr-Al systems. These couples exhibit features such as uphill diffusion and zero flux planes. The interdiffusion coefficients from the new technique along with coefficients reported from other methods are graphed as functions of composition. The coefficients calculated from the new technique …
Chemical Structure - Nonlinear Optical Property Relationships For A Series Of Two-Photon Absorbing Fluorene Molecules, Joel Mccajah Hales
Chemical Structure - Nonlinear Optical Property Relationships For A Series Of Two-Photon Absorbing Fluorene Molecules, Joel Mccajah Hales
Electronic Theses and Dissertations
This dissertation reports on the investigation of two-photon absorption (2PA) in a series of fluorenyl molecules. Several current and emerging technologies exploit this optical nonlinearity including two-photon fluorescence imaging, three-dimensional microfabrication, site-specific photodynamic cancer therapy and biological caging studies. The two key features of this nonlinearity which make it an ideal candidate for the above applications are its quadratic dependence on the incident irradiance and the improved penetration into absorbing media that it affords. As a consequence of the burgeoning field which exploits 2PA, it is a goal to find materials that exhibit strong two-photon absorbing capabilities. Organic materials are …
Design And Hardware Implementation Of A Novel Scrambling Security Algorithm For Robust Wireless Local Area Networks, Mohit Jagetia
Design And Hardware Implementation Of A Novel Scrambling Security Algorithm For Robust Wireless Local Area Networks, Mohit Jagetia
Electronic Theses and Dissertations
The IEEE802.11 standard for wireless networks includes a Wired Equivalent Privacy (WEP) protocol, which is a popular wireless secure communication stream cipher protocol approach to network security used to protect link-layer communications from eavesdropping and other attacks. It allows user to communicate with the user; sharing the public key over a network. It provides authentication and encrypted communications over unsecured channels. However, WEP protocol has an inherent security flaw. It is vulnerable to the various attacks, various experiments has proved that WEP fails to achieve its security goals. This thesis entails designing, evaluating and prototyping a wireless security infrastructure that …