Engineering Commons^™

An Investigation Of Multi-Dimensional Evolutionary Algorithms For Virtual Reality Scenario Development, Scott Papson

Theses and Dissertations

Virtual reality (VR) has emerged as a powerful visualization tool for design, simulation, and analysis in modem complex industrial systems. The primary motivation for this thesis is to develop a framework for the effective use of VR in design-simulation-analysis cycles, particularly in situations involving large, complex, multi-dimensional data-sets. This thesis develops a framework that is intended to support not only the integration of such data for visual, interactive, and immersive displays, but also provides a method for performing risk analysis. Previously "static" VR environments are enhanced with time-evolutionary capabilities. Four candidate algorithms are evaluated for this purpose – deterministic modeling, …

Three-Dimensional Shape Characterization For Particle Aggregates Using Multiple Projective Representations, Jonathan Paul Corriveau

Theses and Dissertations

Shape descriptors are used extensively in computer vision/automated recognition applications such as fingerprint matching, robotics, character recognition, etc. The conventional two-dimensional shape descriptors used in these applications do not readily lend themselves to compact representations in three dimensions. The situation is even more challenging when one attempts to numerically describe the three-dimensional shapes of a mixture of objects such as in an aggregate mix.

The goal of this study is the design, development and validation of automated image processing algorithms that can estimate three-dimensional shape-descriptors for particle aggregates. The thesis demonstrates that a single set of numbers representing a composite …

Daubechies And Quadratic B-Spline Wavelets For Automated Early Diagnosis Of Alzheimer's Disease, Genevieve Jacques

Theses and Dissertations

Alzheimer's disease is a neurological disorder characterized by nerve degeneration and neuronal death. The diagnosis of Alzheimer's disease at an early stage is a major concern due to the lack of a standard and effective diagnosis procedure available to community healthcare providers, as well as the increasing numbers of the elderly population affected. Clinical evaluation, the standard AD diagnostic procedure conducted at major university hospitals and research clinics, achieves, on average, a positive predictive value of 93%, with a sensitivity of 83%, specificity of 55% and an overall accuracy of 75%. An effective and objective tool for early diagnosis of …

Vlsi Implementation Of An Efficient Method For The Computation Of Line Spectral Frequencies, David L. Reynolds

Theses and Dissertations

In speech coding applications using linear predictive techniques, the computation of line spectral frequencies (LSFs) from the predictor coefficients is an extremely computationally intensive task. The unique properties of the symmetric and antisymmetric polynomial roots limit the region which must be searched, however it is still necessary to perform a root-finding algorithm on a high-order polynomial.

Certain algorithms have been developed to reduce the complexity of the root finding exercise. One such algorithm, developed by Ramachandran and Kabal, takes advantage of certain properties of the symmetric and antisymmetric polynomials to map the upper portion of the unit circle onto the …

Heterogeneous Multi-Sensor Data Fusion Using Geometric Transformations And Parzen Windows For The Nondestructive Evaluation Of Gas Transmission Pipelines, Joseph Anthony Oagaro

Theses and Dissertations

The natural gas transmission pipeline network in the United States is a key component of the nation's energy supply infrastructure and extends for over 280,000 miles and has an average age of over 60 years. The integrity of the pipeline is maintained by periodic inline inspections using magnetic or ultrasonic pigs. Defect characterization algorithms developed using current pigging data are hampered by the fact that single inspection techniques (either magnetic or ultrasonic) do not yield sufficient information for accurately and repeatably characterizing defects. This thesis demonstrates that defect characterization algorithms using multiple inspection techniques can accomplish this task. In particular, …

Finite Difference Time Domain Analysis Of Fractal Antennas Used In Wireless Communications, Chritz Adenauer Duncan

FIU Electronic Theses and Dissertations

The advances in wireless technology and the ever-growing demand for multiband and smaller antennas in wireless communications has led to the field of mathematics known as fractal. The use of fractal geometry in antenna design has created a significant amount of interest within the wireless communications societies and most importantly, antenna design.

This thesis investigates the performance and optimization of fractal antennas used in wireless communications. The principle analytical tool utilized in the study is the Finite Difference Time Domain technique (FDTD). This numerical method was applied to calculate the electromagnetic propagation characteristics of the Sierpinski gasket and Koch snowflake …

Influence Of Connection Placement To The Behavior Of Precast Concrete Exterior Beam-Column Joint, Elly Tjahjono, Heru Purnomo

Makara Journal of Technology

Influence of Connection Placement to the Behavior of Precast Concrete Exterior Beam-Column Joint. This paper presents an experimental study on the influence of connection placement to the behaviour of exterior beamcolumn joint of precast concrete structure under semi cyclic loading. Four half-scale beam-column specimens were investigated. Three beam-columns were jointed through connection that are placed in beam-column joint region and the forth is connected at the plastic hinge potensial region of the beam. Crack patterns, strength, stiffness and ductility of the test specimens have been evaluated. The test result indicated that all beam-column specimens show good ductility behavior.

The Effects Of Influent Debit On Hydrodynamic Characteristic Of Bojongsoang Facultative Pond: Without Wind Effects, Rositayanti Hadisoebroto, Suprihanto Notodarmojo

Makara Journal of Technology

The Effects of Influent Debit on Hydrodynamic Characteristic of Bojongsoang Facultative Pond: Without Wind Effects. The performance of facultative pond in Bojongsoang WWTP have reported to be unstable. One of the cause of the unstable performance is the hydrodynamic characteristics that not met the criterion. The improper hydrodynamic characteristics are included the existence of dead-zone, the short-circuiting, and the turbulence due to eddy current. The study was to analyze the effect of the influent debit variation on the hydrodynamic characteristics of the pond using mathematical model. The two-dimensional hydrodynamic model was built from two hydrodynamic equations which are continuity and …

Optic Properties On Aggase2 Polycristal Fabrication, A. Harsono Soepardjo, I Dewa Made Janusetiawan

Makara Journal of Technology

Optic Properties on AgGaSe2 Polycristal Fabrication. Polycristal AgGaSe2, is compound (I-III-VI2) a semiconductor as basic material for thin film for solar cell. Polycristal was succesfully grown using Bridgmann Method, heated on sequential temperature treatment until 850°C and cooled down slowly until room temperature. Results observed were in the form of ingot (bars) with more or less 3 cm length and 13 mm in diameter. By using X-Ray Fefraction, composition obtained of each element (weight %) was Ag = 29,3996 %, Ga = 36,8123 % and Se = 30,29 % while using X-Ray Difraction lattice parameter obtained/calculated a = 4,4112 Å, …

Modelling And Simulation Of Packed Bed Catalytic Converter For Oxidation Of Soot In Diesel Powered Vehicles Flue Gas, Mohammad Nasikin, Praswasti P.D.K. Wulan, Vita Andrianty

Makara Journal of Technology

Modelling and Simulation of Packed Bed Catalytic Converter for Oxidation of Soot in Diesel Powered Vehicles Flue Gas. Diesel vehicle is used in Indonesia in very big number. This vehicle exhausts pollutants especially diesel soot that can be reduces by using a catalytic converter to convert the soot to CO2. To obtain the optimal dimension of catalytic converter it is needed a model that can represent the profile of soot weight, temperature and pressure along the catalytic converter. In this study, a model is developed for packed bed catalytic converter in an adiabatic condition based on a kinetic study that …

Fuel Injection System For One Cylinder Motor Cycle Engine, Bambang Sugiarto

Makara Journal of Technology

Fuel Injection System for One Cylinder Motor Cycle Engine. Fuel injection has been developed for many years. But its common application is limited on car’s engine. With many reason fuel injection systems in motorcycle one cylinder engine has not been widely used yet. Fuel Injection System allows the amount of fuel, injected to be controlled appropriate to engine parameters such as engine speed, amount of air inducted to cylinder, temperature, for each cycle, over the entire engine operating conditions. This fuel injection research is done to find out the Volumetric Efficiency of the intake manifold system, the amount of fuel …

Byu Micro-Sar: A Very Small, Low-Power Lfm-Cw Synthetic Aperture Radar, Michael Israel Duersch

Theses and Dissertations

Brigham Young University has developed a low-cost, light-weight, and low power consumption SAR for flight on a small unmanned aerial vehicle (UAV) at low altitudes. This micro-SAR, or uSAR, consumes only 18 watts of power, ideal for application on a small UAV. To meet these constraints, a linear frequency modulation-continuous wave (LFM-CW) transmit signal is utilized. Use of an LFM-CW signal introduces some differences from the typical strip map SAR processing model that must be addressed in signal processing algorithms. This thesis presents a derivation of the LFM-CW signal model and the associated image processing algorithms used for the uSAR …

High Accuracy Distributed Target Detection And Classification In Sensor Networks Based On Mobile Agent Framework, Xiaoling Wang

Doctoral Dissertations

High-accuracy distributed information exploitation plays an important role in sensor networks. This dissertation describes a mobile-agent-based framework for target detection and classification in sensor networks. Specifically, we tackle the challenging problems of multiple- target detection, high-fidelity target classification, and unknown-target identification.

In this dissertation, we present a progressive multiple-target detection approach to estimate the number of targets sequentially and implement it using a mobile-agent framework. To further improve the performance, we present a cluster-based distributed approach where the estimated results from different clusters are fused. Experimental results show that the distributed scheme with the Bayesian fusion method have better performance …

Hmm - Impact Of Window Size And Frame Size On Asr Performance, Sanjay A. Patil, Jun Won Suh

Sanjay A. Patil

No abstract provided.

Charging-Induced Asymmetry In Molecular Conductors, Eric Polizzi, S. Datta, A. Ghosh, M. Paullson, F. Zahhid

Eric Polizzi

We investigate the origin of asymmetry in various measured current-voltage (I-V) characteristics of molecules with no inherent spatial asymmetry, with particular focus on a recent break junction measurement. We argue that such asymmetry arises due to unequal coupling with the contacts and a consequent difference in charging effects, which can only be captured in a self-consistent model for molecular conduction. The direction of the asymmetry depends on the sign of the majority carriers in the molecule. For conduction through highest occupied molecular orbitals (i.e., HOMO or p-type conduction), the current is smaller for positive voltage on the stronger contact, while …

Acoustic Wave Based Biosensor, Aditya A. Vijh

Masters Theses

Quartz Crystal Microbalances (QCMs) have been widely used for detection of various chemical and biological species in liquid media. In this work an improved binding of Protein A and IgG molecules on QCM biosensors by modifying the gold surface of the quartz crystal with an ultra thin polystyrene film followed by an acidic treatment has been reported. Protein A and IgG immobilizations on quartz crystals with the polystyrene film represented a 65% increase and a 40% increase respectively when compared to immobilization done directly onto the crystals. Atomic Force Microscopy (AFM) has been used to investigate and study the biomolecular …

Cross-Layer Design Of A Dynamic Resource Allocation Control For The Next Multimedia Wireless Generation 1xev-Dv Systems, Mohamed Bourouha

Masters Theses

1xEV-DV has been proposed as one of the standards of the next MultimediaWire- less Generation (MWG) systems, which adopts new techniques to enhance wireless data Quality of Service (QoS). Despite the recent research efforts in mapping QoS pa- rameters cross the different layers, there is still no cross layer QoS design that focuses in providing QoS assurances in the 1xEV-DV. Moreover, many possible combinations of resource parameters have been specified in the current standard. However, there are no specifications about the dynamic resource allocation. In this thesis, a suite of Cross Layer Multiuser Diversity Modules are proposed. These modules include …

A Two-Phase Cooling Method Using R134a Refrigerant To Cool Power Electronics Devices, Jeremy Bryant Campbell

Masters Theses

Power electronics are vital to the operation and performance of hybrid-electric vehicles (HEVs) because they provide the interface between the energy sources and the traction drive motor. As with any “real” system, power electronic devices have losses in the form of heat energy during normal switching operation, which has the potential ability to damage or destroy the device. Thus, to maintain reliability of the PE system, the heat energy produced must be removed. Present HEV cooling methods provide adequate cooling effects, but lack sufficient junction temperature control to maintain long-term reliability. This thesis is based on using the automobile’s air …

Hardware Acceleration Of The Embedded Zerotree Wavelet Algorithm, Suresh S. Polisetty

Masters Theses

The goal of this project was to gain experience in designing and implementing a microelectronic system to acclerate the execution of a time-consuming software algorithm, the Embedded Zerotree Wavelet (EZW), which is used in multimedia applications. The algorithm was implemented using MATLAB to be certain it was fully understood and to serve as a validation reference. Then, the algorithm was mapped into a hardware description language, VHDL, and its resulting implementation verified with the golden reference. The hardware description was then targeted to a field-programmable gate array (FPGA). Significant acceleration was achieved since the hardware implementation in a FPGA (Xilinx …

A Mobile Virtual Reality System, Neena Nambiar

Masters Theses

Virtual Reality is the simulation of real or imagined environments, which can be experienced in three dimensions width, height and length. VR simulations provide interactions with the virtual world using external devices.

Virtual Reality systems have been bulky and not suitable for mobile operations. This thesis aims at creating such a mobile virtual reality system, which is portable and lightweight. This system consists of a lightweight notebook or laptop computer. It also includes a head-mounted display, a wireless mouse, a pinch glove, a tracker and wireless networking. This system is built with off-the-shelf components. This system is described in this …

The Design Of Medium Access Control (Mac) Protocols For Energy Efficient And Qos Provision In Wireless Sensor Networks, Yang Liu

Masters Theses

This thesis work focuses on innovative design of media access control (MAC) protocols in wireless sensor networks (WNSs). The characteristics of the WSN inquire that the network service design considers both energy efficiency and the associated application requirement. However, most existing protocols address only the issue of energy efficiency.

In this thesis, a MAC protocol has been proposed (referred to as Q-MAC) that not only minimized the energy consumption in multi-hop WSNs, but also provides Quality of Service (QoS) by differentiating network services based on priority levels prescribed by different applications. The priority levels reflect the state of system resources …

Rf Cmos Receiver Front-End Using A Reflex Amplifier, Radovan Kuzet

Theses and Dissertations - UTB/UTPA

A concept for an RF-CMOS receiver with reflex topology is developed and tested, using OrCad as the primary design and simulation tool. The main idea of the reflex topology is to reuse a Low Noise Amplifier (LNA) stage in the circuit and thus eliminate one high power consumption stage. A Gilbert cell is used for down conversion, with the benefit of low noise and low power while maintaining gain. A set of passive diplexers allows reuse of the LNA at the RF and IF. The complete circuit was simulated using 0.18 micron and 0.5 micron AMI technology. Parameters for the …

Feature Detection Using Linear Structure Modeling And Pca, Kawshif Muhammed Riaz Ahmed

Masters Theses

An algorithm to extract features from digital images such as cracks in concrete bridges for automated inspection is developed. The algorithm is based on the use of Principal Component Analysis (PCA). In general, PCA is used to reduce the dimensionality of a data set that consists of a large number of interrelated variables while retaining the variation present in the original data set. This ability of PCA will be used in this project to identify clusters using two training sets of images. Linear structure modeling is used to emphasize the image features (cracks) prior to applying PCA. Whole images processing …

Carbon Nanotube Based Chemical And Biological Sensors, Srikanth Singamaneni

Masters Theses

Carbon nanotubes are among those wonderful molecules man has discovered by chance. Carbon nanotubes are sheets of graphite rolled up to form seamless cylinders. Their outstanding electrical, mechanical and thermal properties form the inspiration behind this work. This work investigates the possible application of carbon nanotubes as biological sensors for the detection of various biomolecules like Streptavidin and Mouse monoclonal Immunoglobulin-G. Electrical conductance changes of Carbon nanotubes for exposure to alcohol vapors were studied. This thesis demonstrates that these quantum wires can form highly sensitive biological and chemical sensors at molecular level. Although the main focus of the-research was chemical …

Consistency Results For The Roc Curves Of Fused Classifiers, Kristopher S. Bjerkaas

Theses and Dissertations

The U.S. Air Force is researching the fusion of multiple classifiers. Given a finite collection of classifiers to be fused, one seeks a new classifier with improved performance. An established performance quantifier is the Receiver Operating Characteristic (ROC) curve, which allows one to view the probability of detection versus the probability of false alarm in one graph. Previous research shows that one does not have to perform tests to determine the ROC curve of this new fused classifier. If the ROC curve for each individual classifier has been determined, then formulas for the ROC curve of the fused classifier exist …

Trade Space Analysis Of Antenna Array Architecture Using System Modeling Tools, Eugene Johnson

Theses and Dissertations

This trade study has two objectives. The first provides a trade space analysis of differing array architectures and associated radio frequency components using system-modeling tools. The second objective develops system modeling tools aiding similar analysis by other users. These objectives were accomplished by evaluating a selected group of output parameters to include overall system cost, mass, and power consumption, as well as the minimum detectable input level, system spurious free dynamic range, and selected beam spoilage parameters caused by the use of discrete phase shifters. A fixed number of designs were evaluated using simulation. The evaluation process examined input parameter …

Ultra Wide Band Signal Modeling For Radar Receiver Characterization, Robert J. Backscheider

Theses and Dissertations

Results for modeling, simulation, and analysis of interference effects that modern wideband signals have on existing narrowband radar system performance are presented. In particular, radar detection performance is characterized using a basic radar receiver model and operational parameters consistent with those of the ARSR-4 air route surveillance radar. Two modern wideband signals (interferers) are addressed in this work, including the GPS military signal (M-Code signal) and a direct sequence ultra wideband (DS-UWB) waveform meeting outdoor emission restrictions imposed by the Federal Communications Commission (FCC). Interference effects are characterized for an unmodulated sinusoidal pulse as well as linear frequency modulated (LFM) …

Non-Cooperative Detection Of Ultra Wideband Signals, Brett D. Gronholz

Theses and Dissertations

Techniques for the non-cooperative (non-matched filter) detection of impulse-like ultra wideband signals using channelized receiver architectures are developed and evaluated. Each technique considered is modeled and simulations conducted to characterize detection performance, the results of which are compared with the detection performance of three receivers: the matched filter receiver, which provides optimum detection performance in AWGN; the radiometer, or energy detector; and the multi-aperture cross correlation receiver. It is shown that a channelized receiver (with no downconversion) can provide approximately 2.5 dB improvement over the radiometer when performing detection using the temporal-temporal matrix (TTM). The TTM processing technique provides the …

X-Ray Image Processing And Visualization For Remote Assistance Of Airport Luggage Screeners, Yue Zheng

Masters Theses

X-ray technology is widely used for airport luggage inspection nowadays. However, the ever-increasing sophistication of threat-concealment measures and types of threats, together with the natural complexity, inherent to the content of each individual luggage make x-ray raw images obtained directly from inspection systems unsuitable to clearly show various luggage and threat items, particularly low-density objects, which poses a great challenge for airport screeners.

This thesis presents efforts spent in improving the rate of threat detection using image processing and visualization technologies. The principles of x-ray imaging for airport luggage inspection and the characteristics of single-energy and dual-energy x-ray data are …

Thermal Modeling And Imaging Of As-Built Automotive Parts, Vijaya Priya Muthusamy Govindasamy

Masters Theses

Simulation is of significant importance in the automotive industry and can be done for various applications ranging from fluid flow analysis to complex thermal management of components. This thesis describes the method and necessary requirements for thermal modeling of automotive parts. Simulation of under hood and under vehicle automotive poses several challenges, the shape and complexity of the geometry used being the first and foremost to be considered. This thesis addresses the simulation of thermal images of as-built automotive parts using the 3D meshes generated from 3D modeling tools, CAD meshes and reverse engineered meshes.

Thermal modeling requires complete knowledge …