Engineering Commons^™

Advanced Thermosonic Wire Bonding Using High Frequency Ultrasonic Power: Optimization, Bondability, And Reliability, Minh-Nhat Ba Le

Master's Theses

Gold wire bonding typically uses 60 KHz ultrasonic frequency. Studies have been reported that increasing ultrasonic frequency from 60KHz to 120KHz can decrease bonding time, lower bonding temperature, and/or improve the bondability of Au metalized organic substrates. This thesis presents a systematic study of the effects of 120 KHz ultrasonic frequency on the reliability of fine pitch gold wire bonding. Two wire sizes, 25.4 and 17.8 μm in diameter (1.0 and 0.7 mil, respectively) were used. The gold wires were bonded to metalized pads over organic substrates with five different metallization. The studies were carried out using a thermosonic ball …

Synthetic Aperture Radar Imaging Simulated In Matlab, Matthew Schlutz

Master's Theses

This thesis further develops a method from ongoing thesis projects with the goal of generating images using synthetic aperture radar (SAR) simulations coded in MATLAB. The project is supervised by Dr. John Saghri and sponsored by Raytheon Space and Airborne Systems. SAR is a type of imaging radar in which the relative movement of the antenna with respect to the target is utilized. Through the simultaneous processing of the radar reflections over the movement of the antenna via the range Doppler algorithm (RDA), the superior resolution of a theoretical wider antenna, termed synthetic aperture, is obtained. The long term goal …

Attitude Determination Of A Student Satellite Using On-Orbit Magnetometer And Temperature Data, Jacob Daniel Dimiceli

Master's Theses

An extended Kalman filter is modified to support only magnetometer data as a measurement for spacecraft attitude information. Actual on-orbit data from a student satellite is used in the filter from three different time periods and varying data frequencies. The extended Kalman filter has a thermal model that utilizes external temperature data as a verification tool for filter convergence and for parameter tuning. It can capture the frequency of temperature changes and the correct side panel being lit by the sun as long as the filter converges properly, but not the magnitude of the temperature at a specific time. A …

Development Of An Integrated Gaussian Process Metamodeling Application For Engineering Design, Collin R. Baukol

Master's Theses

As engineering technologies continue to grow and improve, the complexities in the engineering models which utilize these technologies also increase. This seemingly endless cycle of increased computational power and demand has sparked the need to create representative models, or metamodels, which accurately reflect these complex design spaces in a computationally efficient manner. As research into metamodeling and using advanced metamodeling techniques continues, it is important to remember design engineers who need to use these advancements. Even experienced engineers may not be well versed in the material and mathematical background that is currently required to generate and fully comprehend advanced complex …

Application Of Pv Panels In Large Multi-Story Buildings, Sara Kayal

Master's Theses

Application of PV Panels in Large Multi-Story Buildings Feasibility Study Sara Kayal

The awareness of global warming along with an ever increasing demand for a new source of energy has brought a strong interest in harnessing natural resources such as solar energy. This thesis evaluates the viability of applying photovoltaic (PV) panels in high-rise commercial buildings of around 20 stories. Specifically, the thesis is intended to provide a pre-planning tool during the early design stage for architects and designers who are considering the deployment of PV panels in new multi-story construction.

The first three chapters cover a comprehensive literature review …

Assessing Near-Field Outdoor Concentration Variability From Residential Wood Smoke Combustion Sources, Courtney E. Ward

Master's Theses

ABSTRACT Assessing Near-Field Outdoor Concentration Variability from Residential Wood Smoke Combustion Sources Courtney Ward The primary goal of this research was to determine whether near field effects from residential wood smoke emissions have a significant impact on acute and/or average PM2.5 concentrations, and therefore health risks. To this end, three primary research objectives were addressed: (1) measurement of the variability of wood smoke concentrations within a residential neighborhood with wood smoke sources, (2) establishment of whether the magnitude of near-source contributions to exposures can be estimated using typically available data, and (3) prediction of wood smoke concentrations using linear regression …

A Study Of Dempster-Shafer's Theory Of Evidence In Comparison To Classical Probability Combination, Scott J. Seims

Master's Theses

ABSTRACT

A Study of Dempster-Shafer’s Theory of Evidence in Comparison to Classical Probability Combination

Scott J. Seims

This thesis is an assessment on the effectiveness of Dempster-Shafer’s Theory of Evidence in comparison to Classical Probabilistic Combination as it applies to Synthetic Aperture Radar (SAR) Automatic Target Recognition (ATR). A three feature based classifier (peaks, corners and edges) ATR system is presented. These classifiers are assumed to be independent. The results of both the weight-based Maximum Likelihood and Dempster-Shafer’s Theory of Evidence data fusion techniques are presented.

Using Dempster-Shafer an accuracy of 77.50 percent is obtained, which is less than the …

Mechanical Simulation Of Articular Cartilage Based On Experimental Results, Kevin Matthew Stewart

Master's Theses

Recently, a constituent based cartilage growth finite element model (CGFEM) was developed in order to predict articular cartilage (AC) biomechanical properties before and after growth. Previous research has noted limitations in the CGFEM such as model convergence with growth periods greater than 12 days. The main aims of this work were to address these limitations through (1) implementation of an exact material Jacobian matrix definition using the Jaumann-Kirchhoff (J-K) method and (2) quantification of elastic material parameters based upon research findings of the Cal Poly Cartilage Biomechanics Group (CPGBG). The J-K method was successfully implemented into the CGFEM and exceeded …

General Direction Routing Protocol, Sean Michael Lydon

Master's Theses

The General Direction Routing Protocol (GDRP) is a Wireless Sensor Network (WSN)

multi-path routing protocol which abstracts localization information (commonly GPS

coordinates) into relative direction information in order to perform routing decisions. By

generating relative direction information GDRP is able to operate with fewer precision

requirements than other protocols. This abstraction also allows the integration of other emerging

hardware-based localization techniques, for example, Beamforming Sensor Arrays.

GDRP does not specifically address the next hop a packet should take, but instead specifies a

direction it should travel. This direction abstraction allows for multiple paths to be taken through

the network thus …

Analysis & Design Of Improved Multiphase Interleaving Dc-Dc Converter With Input-Output Bypass Capacitor, Rudi Rudianto

Master's Theses

As the transistor count per chip in computer microprocessors surpasses one billion, the semiconductor industry has become more and more concerned with meeting processor’s power requirements. This poses a design challenge for the power supply module, especially when the processor operates at low voltage range. For example, the electrical requirement for the newest Intel microprocessors has exceeded 100A with an input voltage of approximately 1V. To overcome this problem, multiphase DC-to-DC converters encased in a voltage regulator module (VRM) have become the standard means of supplying power to computer microprocessor.

This study proposes a new topology for the multiphase DC-to-DC …

Store And Forward Routing For Sparse Pico-Satellite Sensor Networks With Data-Mules, Trevor Joseph Koritza

Master's Theses

Satellites are playing an increasingly important role in collecting scientific information, providing communication services, and revolutionizing navigation. Until recently satellites were large and very expensive, creating a high barrier to entry that only large corporations and government agencies could overcome. In the past few years the CubeSat project at California Polytechnic University in San Luis Obispo (Cal Poly) has worked to refine the design and launching of small, lightweight, and less expensive satellites called pico-satellites, opening space up to a wider audience. Now that Cal Poly has the launch logistics and hardware under control, a new problem has arisen. These …

Novel Current-Fed Boundary-Mode Parallel-Resonant Push-Pull Converter, Jonathan David Paolucci

Master's Theses

The inherent difficulty in designing high voltage power supplies is often compounded by demands of high reliability, high performance, and safe functionality. A proposed high step-up ratio DC-DC converter meets the exacting requirements of applications such as uninterruptible power systems, radar, and pulsed power systems. The proposed DC-DC converter topology combines a multi-phase buck input stage with a novel self-tracking zero-voltage-switching (ZVS) resonant output stage. Traditionally, the inclusion of multiple power processing stages within a power supply topology severely degrades the overall converter efficiency. Due to the inherent high efficiency per stage, however, this effect is minimized. The self-tracking switching …

Prestressing Concrete With Shape Memory Alloy Fibers, Skye M. Orvis

Master's Theses

Concrete is considerably stronger in compression than it is in tension. When cracks form in concrete members, the flexural stiffness of the member decreases and the deflection increases which increases the overall size of the member. Prestressing concrete remedies this problem by inducing a compressive stress in the concrete thereby reducing the net tension in the member and increasing the load required to crack the member. Traditional prestressing is generally limited to large, straight members. During the last decade, shape memory alloys (SMA) have become more prevalent in engineering and civil engineering applications. The shape memory effect refers to the …

The Impact Of Lipid Percentage On Fibrous Cap Stability In Atherosclerotic Lesions, Anita Lorraine Crompton

Master's Theses

Coronary artery disease (CAD) is a common cause of sudden cardiac death. Much of the disease is not completely understood, which makes treatment and prevention difficult. Many researchers are using technology, such as advanced imaging techniques and finite element analysis, to better understand the disease. While there is much progress being made to look at the analysis of actual excised diseased arteries, there is still not a standardized model to predict the future of any one lesion. The purpose of this study is to explore the possibility of creating a standardized model to predict the mechanical stability of the fibrous …

Do Canines Experience The Effects Of Heart Rate Turbulence?, Melanie Ann Gurunathan

Master's Theses

Background

The canine cardiac system has been the model against which many Class III cardiac devices are validated. Thus, it is expected that the canine heart has very similar electrical model to that found in humans. In 1999, the absence of Heart Rate Turbulence (HRT) after a single Pre-Ventricular Contraction (PVC) was linked to high-risk patient after acute myocardial infarction. Studies of HRT were performed on high-risk patients with Holter-Monitors as were most subsequent HRT studies. If HRT could potentially be used as a risk factor of heart disease, it is interesting to study whether HRT is present following a …

A System For Natural Language Unmarked Clausal Transformations In Text-To-Text Applications, Daniel Miller

Master's Theses

A system is proposed which separates clauses from complex sentences into simpler stand-alone sentences. This is useful as an initial step on raw text, where the resulting processed text may be fed into text-to-text applications such as Automatic Summarization, Question Answering, and Machine Translation, where complex sentences are difficult to process. Grammatical natural language transformations provide a possible method to simplify complex sentences to enhance the results of text-to-text applications. Using shallow parsing, this system improves the performance of existing systems to identify and separate marked and unmarked embedded clauses in complex sentence structure resulting in syntactically simplified source for …

Extraction Of Causal-Association Networks From Unstructured Text Data, Brett N. Bojduj

Master's Theses

Causality is an expression of the interactions between variables in a system. Humans often explicitly express causal relations through natural language, so extracting these relations can provide insight into how a system functions. This thesis presents a system that uses a grammar parser to extract causes and effects from unstructured text through a simple, pre-defined grammar pattern. By filtering out non-causal sentences before the extraction process begins, the presented methodology is able to achieve a precision of 85.91% and a recall of 73.99%. The polarity of the extracted relations is then classified using a Fisher classifier. The result is a …

A Highly Abstracted Method Of Fpga-Based Development For Secondary Surveillance Radar Transpond Detection, James Penn Watt

Master's Theses

Traditional FPGA-based digital design is based on writing hardware definition language (HDL) code from scratch. Time to market, cost of development, and the level of training required for designers all can be reduced with a simplified and abstracted design strategy. This project intends to demonstrate a graphical user interface (GUI) layer of abstraction on top of existing commercially produced design aids including MATLAB, Simulink, and Xilinx System Generator. This project performs and demonstrates a specific implementation example of a Secondary Surveillance Radar (SSR) message decoder as proof-of-concept for the abstracted design method. The abstracted digital design methods shown in this …

Time-Frequency Analysis Of Intracardiac Electrogram, Erik Brockman

Master's Theses

The Cardiac Rhythm Management Division of St. Jude Medical specializes in the development of implantable cardioverter defibrillators that improve the quality of life for patients diagnosed with a variety of cardiac arrhythmias, especially for patients prone to sudden cardiac death. With the goal to improve detection of cardiac arrhythmias, this study explored the value in time-frequency analysis of intracardiac electrogram in four steps. The first two steps characterized, in the frequency domain, the waveforms that construct the cardiac cycle. The third step developed a new algorithm that putatively provides the least computationally expensive way to identifying cardiac waveforms in the …

Non-Linear Contact Analysis Of Meshing Gears, Chun Hung Lee

Master's Theses

Gear transmission systems are considered one of the critical aspects of vibration analysis, and it contains various potential faults such as misalignment, cracks, and noise. Therefore, it requires vibration monitoring to ensure the system is operating properly. Case mounted accelerometers are frequently used to monitor frequencies in a system. However, it is not a simple task to identify and interpret the acceleration data since there are many gear mesh frequencies present. One of the approaches utilized by researchers to perform gear diagnostic is Finite Element Modeling. This study focuses on stiffness cycle and meshing stiffness of non-linear quasi-static finite element …

Modeling And Simulation Of Photovoltaic Water Pumping System, Taufik, Akihiro Oi, Makbul Anwari, Mohammad Taufik

Electrical Engineering

This paper presents modeling of a simple but efficient photovoltaic water pumping system. The system employs maximum power point tracker (MPPT). Two MPPT algorithms, subsystems and control methods will be modeled and simulated using Matlab and Simulink with actual irradiance data. Simulation results will be presented in terms of performance parameters such as total energy produced and total volume of water pumped per day. The results further validate that MPPT can significantly improve efficiency and performance of PV water pumping system compared to the system without MPPT.

Performance Analysis Of Shunt Reactive Power Compensators, Taufik, Emili Schaefer, Makbul Anwari, Mohammad Taufik

Electrical Engineering

This paper offers comparative solutions for utility companies to solve the problem of voltage flicker in distribution systems. The solutions entail provision of shunt reactive compensation. Two solutions will be explored: the shunt capacitor and the Static VAR Compensator (SVC). Both solutions are modeled and simulated using PSCAD. Results will be compared by analyzing their performance when subjected to changes on the system, and problems that arise when connected to the system.

Modeling And Simulation Of Multiple-Input Converter System With Equally Drawn Source Power, Taufik, Brian Butterfield, Makbul Anwari, Mohammad Taufik

Electrical Engineering

This paper presents the modeling of a proposed multiple input, single output converter system for use mainly to interface several renewable energy sources into a single load connection point. More specifically, modeling of a system involving ac and dc supplied to the multiple inputs, single output DC-DC converter will be described and then verified via simulation using OrCAD Pspice to exhibit its functionality. Results of the simulation of one model show the achievement of equally supplied source currents. Details of the modeling and the accompanying computer simulation of the proposed converter will be discussed.

Energy Benefits Of Reconfigurable Hardware For Use In Underwater Sensor Nets, Bridget Benson, Ali Irturk, Junguk Cho, Ryan Kastner

Electrical Engineering

Small, dense underwater sensor networks have the potential to greatly improve undersea environmental and structural monitoring. However, few sensor nets exist because commercially available underwater acoustic modems are too costly and energy inefficient to be practical for this applications. Therefore, when designing an acoustic modem for sensor networks, the designer must optimize for low cost and low energy consumption at every level, from the analog electronics, to the signal processing scheme, to the hardware platform. In this paper we focus on the design choice of hardware platform: digital signal processors, microcontrollers, or reconfigurable hardware, to optimize for energy efficiency while …

Multi-Objective Design Of Transient Network Models, Bong Seog Jung, Misgana K. Muleta, Paul F. Boulos

Civil and Environmental Engineering

The optimal design of a water distribution system under transient conditions is formulated as a two-objective optimization problem. The objectives are minimization of the total pipe costs and maximization of the hydraulic reliability for the transient network design model. Unlike most optimization models in which demands are set to their end-of-life levels, this approach assumes that the demand loadings vary throughout the design life of the system. Evolutionary algorithms are applied to support efficient search for Pareto optimal solutions to the dual-objective optimization problem. An example application is presented and relevant conclusions are stated.

Theoretical Analysis Of Alendronate And Risedronate Effects On Canine Vertebral Remodeling And Microdamage, Xiang Wang, Antonia M. Erickson, Matthew R. Allen, David B. Burr, R. Bruce Martin, Scott J. Hazelwood

Biomedical Engineering

Bisphosphonates suppress bone remodeling activity, increase bone volume, and significantly reduce fracture risk in individuals with osteoporosis and other metabolic bone diseases. The objectives of the current study were to develop a mathematical model that simulates control and 1 year experimental results following bisphosphonate treatment (alendronate or risedronate) in the canine fourth lumbar vertebral body, validate the model by comparing simulation predictions to 3 year experimental results, and then use the model to predict potential long term effects of bisphosphonates on remodeling and microdamage accumulation. To investigate the effects of bisphosphonates on bone volume and microdamage, a mechanistic biological model …

Linear Analysis Of Ordinary Bridges Crossing Fault-Rupture Zones, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

Rooted in structural dynamics theory, two approximate procedures for estimating peak responses of linearly elastic “ordinary” bridges crossing fault-rupture zones are presented: response spectrum analysis (RSA) procedure and a linear static analysis procedure. These procedures estimate the peak response by superposing peak values of quasi-static and dynamic responses. The peak quasi-static response in both procedures is computed by static analysis of the bridge with peak values of all support displacements applied simultaneously. In RSA, the peak dynamic response is estimated by dynamic analysis including all significant modes, which is simplified in the latter procedure to static analysis of the bridge …

Nonlinear Analysis Of Ordinary Bridges Crossing Fault-Rupture Zones, Rakesh K. Goel, Anil K. Chopra

Civil and Environmental Engineering

Rooted in structural dynamics theory, three approximate procedures for estimating seismic demands for bridges crossing fault-rupture zones and deforming into their inelastic range are presented: modal pushover analysis (MPA), linear dynamic analysis, and linear static analysis. These procedures estimate the total seismic demand by superposing peak values of quasi-static and dynamic parts. The peak quasi-static demand in all three procedures is computed by nonlinear static analysis of the bridge subjected to peak values of all support displacements applied simultaneously. In the MPA and the linear dynamic analysis procedures, the peak dynamic demand is estimated by nonlinear static (or pushover) analysis …

Development Of An In-Vitro Tissue Engineered Blood Vessel Mimic Using Human Large Vessel Cell Sources, Dimitri E. Delagrammaticas

Master's Theses

Tissue engineering is an emerging field that offers novel and unmatched potential medical therapies and treatments. While the vast aim of tissue engineering endeavors is to provide clinically implantable constructs, secondary applications have been developed to utilize tissue-engineered constructs for in-vitro evaluation of devices and therapies. Specifically, in-vitro blood vessel mimics (BVM) have been developed to create a bench-top blood vessel model using human cells that can be used to test and evaluate vascular disease treatments and intravascular devices. Previous BVM work has used fat derived human microvascular endothelial cells (EC) sodded on an ePTFE scaffold. To create a more …

Implementation Of Physiologic Flow Conditions In A Blood Vessel Mimic Bioreactor System For The Evaluation Of Intravascular Devices, Marc Cody Dawson

Master's Theses

The prevalence and devastating nature of cardiovascular diseases has led to many advancements in the therapies used to treat the millions of patients that suffer as a result of these conditions. As coronary artery disease (CAD) is the most common of these cardiovascular conditions, it is a major focus of research among the medical industry. Although lifestyle changes and drug therapies can treat early CAD, more advanced cases often require more definitive interventions. In conjunction with angioplasty, stenting of an occluded vessel has shown significant success in preventing restenosis. However, as with nearly every therapeutic process in the medical field, …