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A Preliminary Study Of Electrocrystallization Of Bismuth On Glassy Carbon, Min-Li Yang, Zhan-Jun Zhang May 2005

A Preliminary Study Of Electrocrystallization Of Bismuth On Glassy Carbon, Min-Li Yang, Zhan-Jun Zhang

Journal of Electrochemistry

The electrocrystallization of bismuth on glassy carbon electrodes (GCEs) from nitrate solutions was studied by cyclic voltammetry and chronoamperometry. Cyclic voltammograms exhibit a crossover between the cathodic and anodic branches, characteristic of the formation of bismuth nuclei on GCEs, and show that the bismuth electrocrystallization on GCEs is a diffusion-controlled reaction. The current transients were analyzed with the Scharifker and the Heerman equations. With the increaseof Bi3+ concentration, the non-dimensional plots leaned to the theoretical curve for 3D instantaneous nucleation and growth. The overpotential dependence of nucleation and growth mechanism was also found. With the increase of overpotential, the …

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Secure Stochastic Multi-Party Computation For Combinatorial Problems, Marius C. Silaghi, Gerhard Friedrich May 2005

Secure Stochastic Multi-Party Computation For Combinatorial Problems, Marius C. Silaghi, Gerhard Friedrich

Electrical Engineering and Computer Science Faculty Publications

High levels of security often imply that the computation time should be independent of the value of involved secrets. When the expected answer of the solver is either a solution or "unsatisfiable", then the previous assumption leads to algorithms that take always the computation time of the worst case. This is particularly disturbing for NP-hard combinatorial problems. Here we start from the observation that sometimes (specially for hard problems) users find it acceptable to receive as answer either a solution, the answer "unsatisfiable" or a failure with meaning "don't know". More exactly users accept "incomplete" solvers. For certain problems privacy …

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Modern Laboratory-Based Education For Power Electronics And Electric Machines, Robert S. Balog, Zakdy Sorchini, Jonathan W. Kimball, Patrick L. Chapman, Philip T. Krein May 2005

Modern Laboratory-Based Education For Power Electronics And Electric Machines, Robert S. Balog, Zakdy Sorchini, Jonathan W. Kimball, Patrick L. Chapman, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

The study of modern energy conversion draws upon a broad range of knowledge and often requires a fair amount of experience. This suggests that laboratory instruction should be an integral component of a power electronics and electric machines curriculum. However, before a single watt can be processed in a realistic way, the student must understand not only the operation of conversion systems but also more advanced concepts such as control theory, speed and position sensing, switching signal generation, gate drive isolation, circuit layout, and other critical issues. Our approach is to use a blue-box module where these details are pre-built …

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Synchronized Line-Scan Lidar/Eo Imager For Creating 3d Images Of Dynamic Scenes: Prototype Ii, Donald C. Anderton May 2005

Synchronized Line-Scan Lidar/Eo Imager For Creating 3d Images Of Dynamic Scenes: Prototype Ii, Donald C. Anderton

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

A second prototype integrated lidar/Electro Optical (EO) camera, or 3D Texel™ camera, has been developed by Utah State University (USU) Center for Advanced Imaging Ladar (CAIL) that collocates, both temporally and spatially, a CMOS digital camera readout with a time-of-flight pulsed lidar1. The first prototype uses a flying spot lidar with a double gimbal whereas this prototype uses a single gimbal and rotating mirror. The selection and design of the second prototype hardware components: lidar, EO camera, computer, synchronization box, power source (AC to DC and battery box) and battery charger is discussed and compared with the first prototype. The …

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Electronics Design Of The Aglite-Lidar Instrument, Scott S. Cornelsen May 2005

Electronics Design Of The Aglite-Lidar Instrument, Scott S. Cornelsen

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The AGLITE-LIDAR instrument is a three-wavelength lidar system being designed and constructed at the Space Dynamics Laboratory under contract from the Agricultural Research Service. Its purpose is to implement a novel new approach to making measurements of gas and particulate pollutants released into the atmosphere by agricultural operations. Once operational, it will provide a means whereby the total flux of pollutants being emitted by agricultural facilities might be measured. This approach is valid even for facilities that may cover several acres. The design of the AGLITE instrument consists of a myriad of different components that are brought together in a …

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System And Method For Joint Source-Channel Encoding, With Symbol Decoding And Error Correction, Khalid Sayood, Michael W. Hoffman, Billy D. Pettijohn May 2005

System And Method For Joint Source-Channel Encoding, With Symbol Decoding And Error Correction, Khalid Sayood, Michael W. Hoffman, Billy D. Pettijohn

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is a system and method for joint source-channel encoding, symbol decoding and error correction, preferably utilizing an arithmetic encoder with operational error detection space; and a combination sequential, and arithmetic, encoded symbol decoder structure.

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Distributed Control Of Hybrid Motor Drives, Shuai Lu, Keith Corzine, T. H. Fikse May 2005

Distributed Control Of Hybrid Motor Drives, Shuai Lu, Keith Corzine, T. H. Fikse

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

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Calibration And Results Of The Equis Ii Plasma Impedance Probe (Pip), Seth D. Humphries May 2005

Calibration And Results Of The Equis Ii Plasma Impedance Probe (Pip), Seth D. Humphries

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents the calibration process and analysis results for the two Plasma Impedance Probe (PIP) units that were flown as part of the NASA Equis-I I campaign from the Kwajalein Atoll. The work of calibration that was presented by Krishna Kurra for the PIP on the Floating Potential Measurement Unit (FPMU) is improved and extended herein. The sweeping impedance probe (SIP), the instrument formerly known as plasma sweeping probe (PSP), is an integral part of the PIP. For the SIP, the calibration presented in this work, calibration error less than 5% error is achieved. The calibration is applied to …

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Nanoindentation Technique For Characterizing Cantilever Beam Style Rf Microelectromechanical Systems (Mems) Switches, Hyukjae Lee, Ronald A. Coutu Jr., Shankar Mall, Paul E. Kladitis Apr 2005

Nanoindentation Technique For Characterizing Cantilever Beam Style Rf Microelectromechanical Systems (Mems) Switches, Hyukjae Lee, Ronald A. Coutu Jr., Shankar Mall, Paul E. Kladitis

Electrical and Computer Engineering Faculty Research and Publications

A nanoindentation technique was used to mechanically actuate a radio frequency micro-switch along with the measurement of contact resistance to investigate its applicability to characterize deflection and contact resistance behaviors of micro-sized cantilever beam switches. The resulting load–displacement relationship showed a discontinuity in slope when the micro-switch closed. The measured spring constants reasonably agreed with theoretical values obtained from the simple beam models. The change in contact resistance during test clearly indicated micro-switch closure but it did not coincide exactly with the physical contact between two electric contacts due to a resistive contaminated film.

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Higher Radix Floating-Point Representations For Fpga-Based Arithmetic, Bryan Christopher Catanzaro Apr 2005

Higher Radix Floating-Point Representations For Fpga-Based Arithmetic, Bryan Christopher Catanzaro

Theses and Dissertations

Field Programmable Gate Arrays (FPGAs) are increasingly being used for high-throughput floating-point computation. It is forecasted that by 2009, FPGAs will provide an order of magnitude greater sustained floating-point throughput than conventional processors. FPGA implementations of floating-point operators have historically been designed to use binary floating-point representations, as do general purpose processors. Binary representations were chosen as the standard over three decades ago because they provide maximal numerical accuracy per bit of floating-point data. However, the unique nature of FPGA-based computation makes numerical accuracy per unit of FPGA resources a more important measure of the usefulness of a given floating-point …

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Personalized Ranking Of Search Results With Implicitly Learned User Interest Hierarchies, Hyoung-Rae Kim, Philip K. Chan Apr 2005

Personalized Ranking Of Search Results With Implicitly Learned User Interest Hierarchies, Hyoung-Rae Kim, Philip K. Chan

Electrical Engineering and Computer Science Faculty Publications

Web search engines are usually designed to serve all users, without considering the interests of individual users. Personalized web search incorporates an individual user's interests when deciding relevant results to return. We propose to learn a user profile, called a user interest hierarchy (UIH), from web pages that are of interest to the user. The user's interest in web pages will be determined implicitly, without directly asking the user. Using the implicitly learned UIH, we study methods that rank the results from a search engine. Experimental results indicate that our personalized ranking methods, when used with a popular search engine, …

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Estimating The Dynamic Sensitive Cross Section Of An Fpga Design Through Fault Injection, Darrel E. Johnson Apr 2005

Estimating The Dynamic Sensitive Cross Section Of An Fpga Design Through Fault Injection, Darrel E. Johnson

Theses and Dissertations

A fault injection tool has been created to emulate single event upset (SEU) behavior within the configuration memory of an FPGA. This tool is able to rapidly and accurately determine the dynamic sensitive cross section of the configuration memory for a given FPGA design. This tool enables the reliability of FPGA designs and fault tolerance schemes to be quickly and accurately tested. The validity of testing performed with this fault injection tool has been confirmed through radiation testing. A radiation test was conducted at Crocker Nuclear Laboratory using a proton accelerator in order to determine the actual dynamic sensitive cross …

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A Flexible Circuit-Switched Communication Network For Fpga-Based Soc Design, Clint Richard Hilton Apr 2005

A Flexible Circuit-Switched Communication Network For Fpga-Based Soc Design, Clint Richard Hilton

Theses and Dissertations

As FPGA densities continue to improve, single chips are becoming capable of implementing larger and more complex systems. Even today these systems may include several processors working in conjuction with a handful of other standard interfaces or custom modules. Additional system complexity naturally leads to added complexity throughout the different design and implementation stages. Attempting to design such a system while maintaining high performance and within a reasonable time frame is becoming more and more difficult. Architectural design approaches ranging from direct module interconnection to sophisticated bus schemes have been used to build such systems, all with their own trade-offs. …

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Visible Light Emitting Diodes Fabricated From Soluble Semiconducting Polymers, Alan J. Heeger, David Braun Apr 2005

Visible Light Emitting Diodes Fabricated From Soluble Semiconducting Polymers, Alan J. Heeger, David Braun

Electrical Engineering

Visible light LEDs are produced having a layer of conjugated polymer which is cast directly from solution or formed as a gel-processed admixture with a carrier polymer. The LEDs can be formed so as to emit polarized light.

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Intelligent Control Of Nonlinear Systems With Actuator Saturation Using Neural Networks, Wenzhi Gao Apr 2005

Intelligent Control Of Nonlinear Systems With Actuator Saturation Using Neural Networks, Wenzhi Gao

Doctoral Dissertations

Common actuator nonlinearities such as saturation, deadzone, backlash, and hysteresis are unavoidable in practical industrial control systems, such as computer numerical control (CNC) machines, xy-positioning tables, robot manipulators, overhead crane mechanisms, and more. When the actuator nonlinearities exist in control systems, they may exhibit relatively large steady-state tracking error or even oscillations, cause the closed-loop system instability, and degrade the overall system performance. Proportional-derivative (PD) controller has observed limit cycles if the actuator nonlinearity is not compensated well. The problems are particularly exacerbated when the required accuracy is high, as in micropositioning devices. Due to the non-analytic nature of the …

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Programmable Process Flow Networks, Filip D. Cuckov Apr 2005

Programmable Process Flow Networks, Filip D. Cuckov

Electrical & Computer Engineering Theses & Dissertations

A model that introduces programmability to processes occurring in a cargo terminal simulation through the use of a process language is presented in this thesis. The model provides a means for a straight-forward definition, and redefinition of changing processes, their incorporation in the simulation architecture and efficient execution. The model was built to investigate a solution for transforming the cargo terminal simulation CPortS into a process-oriented simulation without hard-coded processes. The approach taken separates the system into an architecture and a set of processes which utilize and interact with the architecture's resources and infrastructure. The processes that take place within …

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Calibrating Seawinds And Quikscat Scatterometers Using Natural Land Targets, David G. Long, Lucas B. Kunz Apr 2005

Calibrating Seawinds And Quikscat Scatterometers Using Natural Land Targets, David G. Long, Lucas B. Kunz

Faculty Publications

The SeaWinds-on-QuikSCAT (QuikSCAT) and SeaWinds-on-ADEOS-2 (SeaWinds) scatterometers measure the normalized radar backscatter (O) of the earth's surface. These identical radar sensors are on different spaceborne platforms in similar orbits. QuikSCAT and SeaWinds data are used to infer near-surface wind vectors, polar sea-ice extent, polar-ice melt events, etc. In order to verify the relative calibration of these sensors, a simple cross calibration based on land backscatter measurements is performed. A first-order polynomial model is used to remove the incidence angle dependence of O for selected regions of the Amazon rainforest and the Sahara Desert. It is shown that the two sensors …

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Trajectory Boundary Modeling Of Time Series For Anomaly Detection, Matthew V. Mahoney, Philip K. Chan Mar 2005

Trajectory Boundary Modeling Of Time Series For Anomaly Detection, Matthew V. Mahoney, Philip K. Chan

Electrical Engineering and Computer Science Faculty Publications

We address the problem of online detection of unanticipated modes of mechanical failure given a small set of time series under normal conditions, with the requirement that the anomaly detection model be manually verifiable and modifiable. We specify a set of time series features, which are linear combinations of the current and past values, and model the allowed feature values by a sequence of minimal bounding boxes containing all of the training trajectories. The model can be constructed in O(n log n) time. If there are at most three features, the model can be displayed graphically for verification, otherwise a …

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Deconvolution Analysis Of Laser Pulse Profiles From 3-D Ladar Temporal Returns, Michael D. Walter Mar 2005

Deconvolution Analysis Of Laser Pulse Profiles From 3-D Ladar Temporal Returns, Michael D. Walter

Theses and Dissertations

Three-dimensional laser imaging systems offer important advantages for battlefield applications, such as night-time targeting and tactical reconnaissance. Recently developed technologies used by coherent detection systems that collect temporally resolved images include arrays of Avalanche Photo-Diodes (APD), Geiger mode APDs, and photo-diodes. Frequently, LADAR systems produce waveforms from each detector that characterize the convolution of the transmitted laser pulse with the target surface. The pulse convolution generates uncertainty as to the precise location of a target surface, which can severely impact various weapon systems' targeting capability. This work analyzes two deconvolution techniques: Wiener filtering and an iterative process derived from the …

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Structure From Motion Using Optical Flow Probability Distributions, Paul Clark Merrell Mar 2005

Structure From Motion Using Optical Flow Probability Distributions, Paul Clark Merrell

Theses and Dissertations

Several novel structure from motion algorithms are presented that are designed to more effectively manage the problem of noise. In many practical applications, structure from motion algorithms fail to work properly because of the noise in the optical flow values. Most structure from motion algorithms implicitly assume that the noise is identically distributed and that the noise is white. Both assumptions are false. Some points can be track more easily than others and some points can be tracked more easily in a particular direction. The accuracy of each optical flow value can be quantified using an optical flow probability distribution. …

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Visualization Of Medical Images Over Mobile Wireless Handheld Devices, Min Wu, Khurana Ashish, Nadar Mariappan, Chang Wen Chen Mar 2005

Visualization Of Medical Images Over Mobile Wireless Handheld Devices, Min Wu, Khurana Ashish, Nadar Mariappan, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

With the novel advances in wireless communication and personal mobile handheld devices, a newly emerging technology of medical visualization on mobile handheld is believed to provide advance service for physicians, especially in image-based diagnosis. In this paper, we have implemented a real time easy-to-use 3D volume visualization system on mobile handheld devices. The doctors could use their wireless handheld devices, such as Pocket PC or PDA, interactively access medical image at anytime and anywhere in the hospital building. System architecture, technical problems and solutions are discussed. Experimental results are clear enough to show this system to be practical for clinic …

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A Novel Multiple Description Scalable Coding Scheme For Mobile Wireless Video Transmission, Haifeng Zheng, Lun Yu, Chang Wen Chen Mar 2005

A Novel Multiple Description Scalable Coding Scheme For Mobile Wireless Video Transmission, Haifeng Zheng, Lun Yu, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

We proposed in this paper a novel multiple description scalable coding (MDSC) scheme based on in-band motion compensation temporal filtering (IBMCTF) technique in order to achieve high video coding performance and robust video transmission. The input video sequence is first split into equal-sized groups of frames (GOFs). Within a GOF, each frame is hierarchically decomposed by discrete wavelet transform. Since there is a direct relationship between wavelet coefficients and what they represent in the image content after wavelet decomposition, we are able to reorganize the spatial orientation trees to generate multiple bit-streams and employed SPIHT algorithm to achieve high coding …

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Capacitance-Voltage Study On The Effects Of Low Energy Electron Radiation On Al0.27Ga0.73N/Gan High Electron Mobility Transistor, Thomas D. Jarzen Mar 2005

Capacitance-Voltage Study On The Effects Of Low Energy Electron Radiation On Al0.27Ga0.73N/Gan High Electron Mobility Transistor, Thomas D. Jarzen

Theses and Dissertations

The effects of radiation on semiconductors are extremely important to the Department of Defense since the majority of the defense informational, navigational and communications systems are now satellite-based. Due to the high radiation tolerance of gallium nitride and a plethora of high temperature, high power and high frequency applications, the prospect that gallium nitride based devices will become key components in a multitude of military satellite-based systems is highly probable. AlGaN/GaN HEMTs were irradiated at low temperature (~80 K) by 0.45 – 0.8 MeV electrons up to fluences of 1×1015 e-/cm2. Following irradiation, low temperature capacitance-voltage measurements …

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Using Liquid Crystal Spatial Light Modulators For Closed Loop Tracking And Beam Steering With Phase Holography, Michael J. Perry Mar 2005

Using Liquid Crystal Spatial Light Modulators For Closed Loop Tracking And Beam Steering With Phase Holography, Michael J. Perry

Theses and Dissertations

Optical Phased Array (OPA) technology offers advantages in the reduction of size, weight, and power of optical steering devices. Nematic liquid crystal (LC) spatial light modulators (SLMs) have been studied as a potential candidate for building non-mechanical OPAs. They can steer a laser beam and split the beam into multiple beams. This thesis builds upon the prior research showing each split beam can be individually controlled, including variation in intensity. A closed loop tracking scenario shows the flexibility of the SLM by tracking and stabilizing an incoming beam. Results show that applying a phase grating to the SLM has limitations …

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An Analysis Of Seawinds Simultaneous Wind/Rain Retrieval In Severe Weather Events, Jeffrey R. Allen Mar 2005

An Analysis Of Seawinds Simultaneous Wind/Rain Retrieval In Severe Weather Events, Jeffrey R. Allen

Theses and Dissertations

Scatterometers, such as SeaWinds, can provide wide coverage of ocean surface winds. They estimate near-surface wind vectors by relating measured radar backscatter to a geophysical model function. However, SeaWinds measurements are also sensitive to rain, and conventional wind retrieval degrades in rainy conditions. An algorithm that exploits SeaWinds' sensitivity to both wind and rain has be developed. This algorithm, termed simultaneous wind/rain retrieval, retrieves both wind vectors and rain rates for a given ocean area. Instantaneous results of simultaneous wind/rain retrieval in Hurricane events is analyzed through comparison with the NEXRAD ground-based radar system. This comparison allows validation of retrieved …

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Zero-Knowledge Proofs For Mix-Nets Of Secret Shares And A Version Of Elgamal With Modular Homomorphism, Marius C. Silaghi Mar 2005

Zero-Knowledge Proofs For Mix-Nets Of Secret Shares And A Version Of Elgamal With Modular Homomorphism, Marius C. Silaghi

Electrical Engineering and Computer Science Faculty Publications

Mix-nets can be used to shuffle vectors of shared secrets. This operation can be an important building block for solving combinatorial problems where constraints are secret to different participants. A main contribution of this paper is to show how participants in the mix-net can provide Zero-Knowledge proofs to convince each other that they do not tamper with the shuffled secrets, and that inverse permutations are correctly applied. The approach is related to the proof of knowing an isomorphism between large graphs. We also make a detailed review and comparison with rationales and analysis of Chaum's and Merritt's mix-nets. Mix-nets offer …

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Optimization Of Automatic Target Recognition With A Reject Option Using Fusion And Correlated Sensor Data, Trevor I. Laine Mar 2005

Optimization Of Automatic Target Recognition With A Reject Option Using Fusion And Correlated Sensor Data, Trevor I. Laine

Theses and Dissertations

This dissertation examines the optimization of automatic target recognition (ATR) systems when a rejection option is included. First, a comprehensive review of the literature inclusive of ATR assessment, fusion, correlated sensor data, and classifier rejection is presented. An optimization framework for the fusion of multiple sensors is then developed. This framework identifies preferred fusion rules and sensors along with rejection and receiver operating characteristic (ROC) curve thresholds without the use of explicit misclassification costs as required by a Bayes' loss function. This optimization framework is the first to integrate both "vertical" warfighter output label analysis and "horizontal" engineering confusion matrix …

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An Evaluation Of Wind Turbine Technology At Peterson Afb, Randy C. Combs Mar 2005

An Evaluation Of Wind Turbine Technology At Peterson Afb, Randy C. Combs

Theses and Dissertations

Wind energy technology is a viable source for attaining the emission reduction and renewable energy use goals set forth by the executive office. In accordance with Executive Orders, the Air Force must reduce greenhouse emissions and energy consumption, and expand the use of renewable energy sources within its facilities nation-wide by year 2010. This mandate requires that the Air Force look at alternative electrical production and rely more on such renewable energy resources as wind power. The specific problem addressed by this research is whether on-site wind energy generation can be more economically feasible than the conventional energy consumption at …

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An Analysis Of Information Assurance Relating To The Department Of Defense Radio Frequency Identification (Rfid) Passive Network, Robert G. Giovannetti Mar 2005

An Analysis Of Information Assurance Relating To The Department Of Defense Radio Frequency Identification (Rfid) Passive Network, Robert G. Giovannetti

Theses and Dissertations

The mandates for suppliers to commence Radio Frequency Identification tagging set by Wal-Mart and the Department of Defense is changing this long-time rumored technology into reality. Despite the many conveniences to automate and improve asset tracking this technology offers, consumer groups have obstinately opposed this adoption due to the perceived weaknesses in security and privacy of the network. While the heated debate between consumers and retailers continues, little to no research has addressed the implications of security on the Department of Defense Radio Frequency Identification network. This thesis utilized a historical analysis of Radio Frequency Identification literature to determine whether …

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Daytime Detection Of Space Objects, Alistair D. Funge Mar 2005

Daytime Detection Of Space Objects, Alistair D. Funge

Theses and Dissertations

Space Situational Awareness (SSA) requires repeated object updates for orbit accuracy. Detection of unknown objects is critical. A daytime model was developed that evaluated sun flares and assessed thermal emissions from space objects. Iridium satellites generate predictable sun glints. These were used as a model baseline for daytime detections. Flares and space object thermal emissions were examined for daytime detection. A variety of geometric, material and atmospheric characteristics affected this daytime detection capability. In a photon noise limited mode, simulated Iridium flares were detected. The peak Signal-to- Noise Ratios (SNR) were 6.05e18, 9.63e5, and 1.65e7 for the nighttime, daytime and …

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