Engineering Commons^™

Susceptibility Scanning As Failure Analysis Tool For System-Level Electrostatic Discharge (Esd) Problems, Giorgi Muchaidze, Jayong Koo, Qing Cai, Tun Li, Lijun Han, Andrew Martwick, Kai Wang, Jin Min, James L. Drewniak, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

Susceptibility scanning is an increasingly adopted method for root cause analysis of system-level immunity sensitivities. It allows localizing affected nets and integrated circuits (ICs). Further, it can be used to compare the immunity of functionally identical or similar ICs or circuit boards. This paper explains the methodology as applied to electrostatic discharge and provides examples of scan maps and signals probed during immunity scanning. Limitations of present immunity analysis methods are discussed.

Simulation Of Multicultural Factors In Terrorism Networks, Jared Townsley

Industrial Engineering Undergraduate Honors Theses

As globalization extends its influence to the far corners of the world, rapid developments and changes are taking place economically, socially, and environmentally. Cultural differences between and within organizations have become significant during the past few years as politics and marketplaces expand globally to include multiple nationalities, beliefs, and value systems. Unfortunately, terrorism has also felt the effects of globalization as organizations such as Al-Qaeda seek to expand their influence worldwide. Although a considerable amount of research has been conducted to identify key cultural factors that play major roles within organizations, simulation models that attempt to quantify cultural effects are …

Using Ansys Workbench Computer Environment In Turbomachinery Design Process, Patricia Lynn Bowlds

Master's Theses - Daytona Beach

The main focus of designing turbomachinery is to analyze and optimize the aerodynamic efficiency and structural integrity of the machine. The preferred way to perform aerodynamic and structural analysis is to connect the analyses and shorten the analysis time as much as possible. ANSYS, Inc. provides a comprehensive approach to model fluid structure interaction phenomenon in turbomachinery within the ANSYS Workbench environment. This environment combines a number of software components that conduct blade design, fluid dynamic and structural analyses, and pre- and post-processing including mesh generation and overall performance estimation.

The focus of this study is to apply the ANSYS …

An Investigation Of Classical Panel Stiffener Buckling Methods For Modern Airframe Applications, Ryan Timothy Holt

Master's Theses - Daytona Beach

Classical methods for buckling assessment of aircraft panels reinforced by bulb-stiffened flanges differ regarding symmetric versus asymmetric cross-sections. The present research addresses a number of classical derivations of methods with a focus on the work of Dwight Windenburg as published in "The Elastic Stability of Tee Stiffeners" and the expansion of his work to asymmetric sections by E. F Bruhn in Analysis and Design of Aerospace Vehicle Structures. Vagueness in the relevance of geometric symmetry of the bulb exists between Windenburg's plate theory approach, and the accepted industry standard applications defined in the methods of Bruhn. The results presented trace …

Development Of Automatic Cfd Grid Generation For The Design Of The Preliminary Wing Sweep Schedule For The Gulfstream Quiet Supersonic Jet, Ali Kazeneh

Master's Theses - Daytona Beach

The wing sweep schedule for the Gulfstream Quiet Supersonic Jet (wing and body) was investigated using CFD analysis methods. The use of automating the gridding procedure allowed for numerous cases to be investigated. The examination of the drag polar for different Mach cases indicated the optimum corresponding wing sweep position. The study results revealed that for the Mach 0.85 case, the wings should remain at the forward most pivoted position (Ʌ=25°). The Mach 1.1 case indicted that the wings should be in the fully swept back position (Ʌ=60°). The majority of the wing sweep transition occurs from Mach 0.85 to …

Design For Reliability In Microoptelectromechanical Systems (Moems), Abiodun Abiodun Fasoro

Mechanical and Aerospace Engineering Dissertations - Archive

Microelectromechanical systems (MEMS) is an enabling technology for miniaturization. MEMS consist of micron sized moving mechanical structures and electronics fabricated on a suitable substrate such as silicon. MEMS has found applications in virtually every aspect of human life, ranging from the automobile to the aerospace, and from the telecommunications to the consumer electronic industries. Technology integration has led to several subsets of MEMS e.g. microoptoelectromechanical systems (MOEMS), radio-frequency MEMS (RF MEMS), etc. Together with these added functionalities, by way of technology integration come additional issues and challenges never before experienced by packaging engineers. MEMS and MOEMS package requirements vary widely …

Dynamic Modeling, Control And Optimization Of Pem Fuel Cell System For Automotive And Power System Applications, Woon Ki Na

Electrical Engineering Dissertations - Archive

This dissertation is focusing on fuel cell dynamic modeling and control, the optimization design of fuel cell systems, power electronics interface designs, and control for the fuel cell based hybrid system. First, a dynamic PEM fuel cell model is proposed as a nonlinear, multiple-input, multiple-output (MIMO) system so that feedback linearization can be directly utilized and the PEM fuel cells can be protected through the controller. For the design of the dynamic model PEM fuel cells, all possible water effects are considered, and the anode and cathode gas pressures, as well as the fuel cell voltage are defined as the …

Biaxial Mechanical Characterization Of Porcine Periosteum, Phillip Daniel Warren

Bioengineering Theses - Archive

Periosteum is multipotent tissue responsible for cortical bone deposition and is important in fracture repair. Research indicates the periosteum is mediated by similar mechanical signals to those that mediate bone growth and remodeling. Therefore, biaxial mechanical characterization of periosteum can be very informative, indeed. This paper presents the results of the first such examination. The porcine periosteum herein has at least three distinct layers - a cellular layer, an elastin-rich layer, and a collagen-rich layer - the latter two providing structural integrity. Not surprisingly then, the general biaxial mechanical characteristics of periosteum resemble those of other collagen and/or elastin-rich membranes. …

Composition - Microstructure - Property Relationships In Dual Phase Bulk Magnetoelectric Composite, Rashed Adnan Islam

Material Science and Engineering Dissertations - Archive

The coexistence of coupled electrical and magnetic properties in the “magnetoelectric” material has led to the possibility of developing smarter and smaller electronic components. In order to make this possibility a reality, significant efforts are required to understand the science of magnetoelectric (ME) behavior and apply this understanding to develop higher sensitivity material. The primary aims of this thesis are to identify the role of composition, microstructural variables, composite geometry, texturing, post sintering heat treatment, and nanoscale assembly on ME coefficient. The overall objective is to synthesize, characterize and utilize a high ME coefficient composite. The desired range of ME …

Renewable Resource Lactide Derived Materials: Scaled-Up Synthesis, Characterization And Applications, Akhilesh Singh

All Dissertations

Renewable resource monomer, lactide, derived copolymers and terpolymers were synthesized on a few hundred gram scale with specialty/commodity co-monomers such as perfluoropolyether and bisphenol A derivatives. The modifications resulted in improved properties such as surface energy, crystallization, and glass transition temperature of the polylactide.
Ring-opening polymerizations of L-lactide were performed using different block length perfluoropolyethers as macro-initiators and tin octoate as the catalyst. The resultant polylactide-perfluoropolyether-polylactide block copolymers were characterized by various analytical and microscopic techniques such as differential scanning calorimetry, thermogravimetric analysis, nuclear magnetic resonance spectroscopy, dynamic mechanical analysis, wide-angle x-ray diffraction spectroscopy, polarized optical microscopy, etc.
The incorporation …

Release Of Hydrophobic Molecules From Polymer Micelles Into Cell Membranes Revealed By Forster Resonance Energy Transfer Imaging, Hongtao Chen, Sungwon Kim, Shuyi Wang, Kinam Park, Ji-Xin Cheng

Other Nanotechnology Publications

it is generally assumed that polymeric micelles, upon administration into the blood stream, carry drug molecules until they are taken up into cells followed by intracellular release. The current work revisits this conventional wisdom. The study using dual-labeled micelles containing fluorescently labeled copolymers and hydrophobic fluorescent probes entrapped in the polymeric micelle core showed that cellular uptake of hydrophobic probes was much faster than that of labeled copolymers. This result implies that the hydrophobic probes in the core are released from micelles in the extracellular space. Forster resonance energy transfer (FRET) imaging and spectroscopy were used to monitor this process …

Structures And Energetics Of Si Nanotubes From Molecular Dynamics And Density Functional Theory, Amritanshu Palaria, Gerhard Klimeck, Alejandro Strachan

Birck and NCN Publications

We use molecular dynamics (MD) with a first principles-based force field (ReaxFF) and density functional theory (DFT) to predict the atomic structure, energetics and elastic propoerties of Si nanotubes. We find various low-energy and low-symmetry hollow structures with external diameters of about 1 nm. These are the most stable structures in this small-diameter regime reported so far and exhibit properties very different from the bulk. While the cohesive energies of the four most stable nanotubes reported here are similar (from 0.638 to 0.697 eV above bulk Si), they have disparate Young's moduli (from 72 to 123 GPa).

Development, Verification, And Future Applications Of A 3-Dof Entry And Descent Simulation Tool, Shaun Deacon

Master's Theses - Daytona Beach

With any space related mission, the unknown effects are often some of the most important design considerations. These effects must be accounted for in some fashion, and often lead to mission elements being centered around gathering information on the unknown.

It is the purpose of this research to develop and test a tool for simulation of entry, descent, and landing, (EDL) and to present a brief analysis of possible dispersion patterns related to autonomous radiosonde deployment on the surface of Mars.

The EDL simulation tool is written in Matlab. The aerodynamic information used by the tool is obtained with the …

Exploring The Potential For Electromangetophoretic Separation, Thomas Lewis

Chemical Engineering Undergraduate Honors Theses

Current research in mircofluidic technology is underway to develop automatic micro-analyzing chips for medical diagnostic testing. Diagnostic testing often requires separation of specific biological particles from a sample, and many of these molecules contain electric or magnetic properties. This project investigates the potential for separation in electromagnetophoretic and magnetophoretic microfluidic technology. In electromagnetophoresis, the Lorentz force acting on a current carrying medium in a homogeneous magnetic field creates a pressure gradient in the fluid, resulting in an applied force to particles present in the separation medium. This force causes the particle to have a velocity component that is perpendicular to …

Voltage Profile Estimation And Reactive Power Control Of Distribution Feeders, David Timothy Chessmore

Electrical Engineering Dissertations - Archive

Distribution systems are important transportation links for the delivery of electric power. Understanding the system conditions of distribution feeders is vital for controlling power systems and maintaining electricity flow on power grids. With better knowledge of the system conditions on distribution feeders, a deliberate and systematic approach can be taken to achieve more efficient and reliable power delivery. Furthermore, better understanding of system conditions can be useful in reducing operation and maintenance costs in various power system applications such as voltage control and capacitor bank switching. This dissertation presents a novel method for estimating the voltage profile of a radial …

Simultaneous Robot Localization And Mapping Of Parameterized Spatio-Temporal Fields Using Multi-Scale Adaptive Sampling, Muhammad Faizan Mysorewala

Electrical Engineering Dissertations - Archive

This dissertation presents a Multi-scale Adaptive Sampling (AS) framework for combining measurements arriving from mobile robotic sensors of different scales, rates and accuracies, in order to reconstruct a parametric spatio-temporal field. The proposed sampling algorithm, "EKF-NN-GAS", is based on the Extended Kalman Filter (EKF), Radial Basis Function (RBF) Neural Networks and Greedy Search Heuristics. This novel AS algorithm responds to real-time measurements by continuously directing robots to locations most likely to yield maximum information about the sensed field. EKF is used to derive quantitative information measures for sampling locations. In addition, the localization uncertainty of the robots is minimized by …

The Application Of Discrete-Event Simulation For Demining Strategy Evaluation, Hui-Chiao Jen

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Teams of mobile autonomous robots have been proposed for the detection and clearing of landmines. Several competing strategies for automated mine detection have been proposed. This paper will discuss the development of a tool that will support the quantitative analysis of various automated mine detection approaches used in Humanitarian Demining and Military Mine Field Breaching. The approaches used to model mine detection in a scout, breaching, and Humanitarian Demining scenario using a discrete-event simulation analysis tool are discussed. The model assumes that each UGV is autonomous rather than being directly controlled by a centralized command and control system. The algorithm …

Passivation Of Si (100) Surface And Fabrication Of Doping-Free Mosfet, Muhammad Yusuf Ali

Electrical Engineering Dissertations - Archive

Chalcogen atoms have been successfully used for the passivation of GaAs(100) as well as Ge(100) and Si(100) substrates. Unlike GaAs(100) and Ge(100), the native oxide(SiO2) of Si(100) substrate is not soluble in ammonium sulfide solution ((NH4)2Sx) or water, which is a major problem to passivate Si(100) surface in a solution. In this work, a wet chemical process has been developed in which a compatible etchant ammonium hydroxide (NH4OH) is added with a passivating solution ((NH4)2S). Because of the compatibility of the etchant with the passivating solution, native oxide on Si(100) surface is removed in-situ to expose a fresh and clean …

Mitigation Of Vibration In A Permanent Magnet Synchronous Machine Using Field Reconstruction, Umamaheshwar Krishnamurthy

Electrical Engineering Dissertations - Archive

Permanent magnet synchronous machines (PMSM) are widely used due to their unique characteristics including high efficiency, high power density, simple construction, simple maintenance, and relative ease of control. With increasing need for automation, survivable and fault tolerant motor drives are highly in demand in many sectors of industry. Advancement in the area of modern power electronics has allowed researchers a great deal of flexibility in implementing complex control routines. While considerable of focus has been placed on improving schemes of control, not much effort has been put improvements in the performance of electric drives. It is also important to note …

Acuta Enews May 2008, Vol. 37, No. 5

ACUTA Newsletters

ln This Issue

From ACUTA Headquarters.......... Jeri A. Semer, CAE, ACUTA Executive Director

Two Audio Seminars in May

Tech Talk: Femtocells: Designed to Give Cellular Coverage a Boost........................ Kevin Tanzillo, Dux PR 3

Board Approves State of Nominees

DC Update Jeanne Jansenius, Sewanee, The University of the South

Board Report.................. Riny Ledgerwood, San Diego State Univ., ACUTA Sec./Treasurer

Recycle Old Cell Phones

Be a Telecom BMOC: Win Big Buck

Check lt Out: RFls/RFPs, Job Postings, Press Releases

lnfo links.................. Randy Hayes' Univ. of Northern lowa

Be a Moderator or Monitor at the Annual Conference..... Donna Hall, ACUTA Mgr. of Professional …

Biodiesel Production From High Free Fatty Acid Content Feedstocks, Kaewta Suwannakarn

All Dissertations

Biomass, such as animal fats and grease, is one of the better sources for transportation fuels, e.g. biodiesel. Use of such biomass in the biodiesel synthesis decreases the need for fossil energy, provides an outlet for utilizing the abundant resources effectively and economically, results in a cleaner fuel that is biodegradable, renewable, and non-toxic. Free fatty acid (FFA) esterification and triglyceride (TG) transesterification with low molecular weight alcohols are the central reactions for the biodiesel production. The focus of this research is to establish a better fundamental insight into heterogeneous catalysis for biodiesel forming reactions, in an attempt to design …

The Effects Of Build Orientation, Diameter And Printhead Life On The Cylindricity Of Three-Dimensionally Printed Parts, Troy E. Ollison

All-Inclusive List of Electronic Theses and Dissertations

Rapid prototyping (RP) technologies have become more than just a fast and inexpensive way to produce prototypes. Today RP is widely used to produce functional prototypes, end-use parts and tooling as well as visual prototypes. When RP is used for end-use parts with interconnected moving assemblies or for producing metal casting molds which must have sufficient material for machining tolerances, accuracy is very critical. However, in general, accuracy of the finished RP parts is relatively low lll compared to parts produced by traditional manufacturing processes. The understanding of why some of these accuracy differences exist is either unknown or not …

Evaluating Arkansas Roadway Intersection Accidents Using Traffic Safety Analysis Methods: Generalized Estimating Equations And Roadway Observation, Jacob Mercer

Industrial Engineering Undergraduate Honors Theses

Considerable research has been made in recent years to evaluate road traffic safety. This is especially true with the United States, whose international rank in public safety is rapidly declining. In 2004, Arkansas ranked as the third highest in traffic fatalities among all the states. These are striking numbers that reflect the lack of attention that the state has received in terms of evaluating road traffic safety. Historically, this safety is measure by one of two methods: Statistical analyses of historical data or hands-on, observational analyses of present safety conditions. Rarely in research are both methods used within the same …

Random Road Analysis And Improved Gear Ratio Selection Of A Front Wheel Drive Drag Racing Car, Thomas New

All Theses

Drag racing has been around since the 1950's and has become a very popular and very competitive sport. The difference between winning and losing can be hundredths and even thousandths of a second. Drag racing teams need every advantage they can get in order to excel in their field. On-track testing is very expensive and can consume large amounts of time and resources that a race team may not be able to afford.
One way to address this potential problem of high cost is by using computer simulation to show how your drag race car may perform at different tracks …

Immobilization Of Biomolecules On Polymer Scaffolds: A Novel Approach, Joshua Barringer

All Theses

In this thesis, I describe the successful development of a procedure for the step-by-step formation of a multi-layer polymer scaffold on a silicon wafer and the characterization of these materials. Also discussed is the development of a procedure for the non-site specific attachment of a biomolecule to the modified silicon wafer, including scaffolds modified via drop-on-demand, DOD, inkjet printing. Ellipsometry, x-ray photoelectron spectroscopy (XPS), FTIR, fluorometry, and static water contact angle measurements are used to study the nanoscale structure and properties of the interfacial, thin film-modified surfaces. Polymers based on 2-vinyl-4,4-dimethylazlactone (VDMA) are used as the platform onto which biomolecules …

Analysis And Experiments For Tendril-Type Robots, Lara Cowan

All Theses

New models for the Tendril continuous backbone robot, and other similarly constructed robots, are introduced and expanded upon in this thesis. The ability of the application of geometric models to result in more precise control of the Tendril manipulator is evaluated on a Tendril prototype. We examine key issues underlying the design and operation of 'soft' robots featuring continuous body ('continuum') elements. Inspiration from nature is used to develop new methods of operation for continuum robots. These new methods of operation are tested in experiments to evaluate their effectiveness and potential.

Ductile-Regime Machining Of Glass Using The Micromilling Process, Kevin Foy

All Theses

Glass is a homogeneous material with amorphous crystal structure that is produced through the rapid cooling of its molten state below the glass transition temperature. Glass exhibits many excellent mechanical and physical properties, and it is widely used in automotive, communications, optics, electronics, architectural, and biomedical industries. For certain applications such as DNA microarrays, glass components with microfeatures are typically produced using a combination of photolithography and etching processes, which is generally time consuming and can involve hazardous chemicals. It would be ideal to fabricate some glass devices through mechanical micromachining for some rapid prototyping applications of glass-based devices, but …

Storm Water Export Of Nitrogen, Phosphorous, And Carbon From Developing Catchments In The Upper Piedmont Physiographic Province, Laura Reid

All Theses

Impacts on water quality caused by land use change from forests and pastures to housing subdivisions were evaluated in catchments undergoing active development in the upper Piedmont physiographic province of South Carolina. Specific attention was focused on the export of nitrogen, phosphorus and carbon from these catchments during storm events. Three catchments with varying stages of development were compared to categorize the effects of land disturbance. Storm events occurring within a four year period of 2004 through 2007 were studied for changes in water quality within catchment streams. Due to the potential large input of surface runoff to streams following …

Novel Near-Field Microwave And Millimeter Wave Differential Probe Using A Dual-Modulated Single Aperture, Mohamed A. Abou-Khousa, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

A novel differential probe design is introduced in this paper for near-field microwave and millimeter wave non-destructive testing (NDT) and imaging applications. In such applications, the variations in the distance between the probing antenna and the structure under inspection, i.e., standoff distance, can potentially mask the signal of interest, and hence, adversely impact the detection capability of the probe. Differential near-field probes and compensation methods were developed in the past to null out the standoff distance variation effect from the measured signal. The available methods, however, suffer from some limitations such as using two balanced apertures or offering limited range …

A Semi-Analytical Approach For System-Level Electrical Modeling Of Electronic Packages With Large Number Of Vias, Zaw Zaw Oo, En Xiao Liu, Er Ping Li, Xingchang Wei, Yaojiang Zhang, Mark Tan, Le Wei Joshua Li, Rüdiger Vahldieck

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a semi-analytical approach for electrical performance modeling of complex electronic packages with multiple power/ ground planes and large number of vias. the method is based on the modal expansion technique and the method of moments. for the inner package domain with multiple power/ground planes and many vias, the modal expansion method is employed to compute the electromagnetic fields from which the multiport network parameters, e.g., the admittance matrix can be easily obtained. for the top/bottom domain of signal layers, the moment method is used to extract the equivalent resistance, inductance, capacitance, and conductance (RLCG) parameters. the equivalent …