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Shape-Based Recognition Of Targets In Synthetic Aperture Radar Images Using Elliptical Fourier Descriptors, Louis P. Nicoli, Georgios C. Anagnostopoulos Apr 2008

Shape-Based Recognition Of Targets In Synthetic Aperture Radar Images Using Elliptical Fourier Descriptors, Louis P. Nicoli, Georgios C. Anagnostopoulos

Electrical Engineering and Computer Science Faculty Publications

This paper primarily investigates the use of shape-based features by an Automatic Target Recognition (ATR) system to classify various types of targets in Synthetic Aperture Radar (SAR) images. In specific, shapes of target outlines are represented via Elliptical Fourier Descriptors (EFDs), which, in turn, are utilized as recognition features. According to the proposed ATR approach, a segmentation stage first isolates the target region from shadow and ground clutter via a sequence of fast thresholding and morphological operations. Next, a number of EFDs are computed that can sufficiently describe the salient characteristics of the target outline. Finally, a classification stage based …

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Electric Motor Efficiency Under Variable Frequencies And Loads, Charles M. Burt, Xianshu Piao, Franklin Gaudi, Bryan Busch, Taufik Apr 2008

Electric Motor Efficiency Under Variable Frequencies And Loads, Charles M. Burt, Xianshu Piao, Franklin Gaudi, Bryan Busch, Taufik

Electrical Engineering

This paper details a study performed by the Irrigation Training and Research Center to determine motor performances under varying speeds [induced by a variable frequency drives (VFD) controller]and loads. A further goal of the study was to provide sufficient information to designers so that they could estimate total pumping plant power usage with a VFD-controlled installation. Motors were tested with a VFD as well as across-the-line. On average, the relative efficiency of the electrical system with a VFD may be approximately 8% lower than the relative efficiency of a properly designed, full-load across-the-line system. If one considers actual field operating …

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Secured Hardware Design - An Overview, S. Burugapalli, Waleed K. Al-Assadi Apr 2008

Secured Hardware Design - An Overview, S. Burugapalli, Waleed K. Al-Assadi

Electrical and Computer Engineering Faculty Research & Creative Works

Security is a prime concern in the design of a wide variety of embedded systems and security processors. So the customer security devices such as smart cards and security processors are prone to attack and there are on going research to protect these devices from attackers who intend to extract key information from these devices. Also an active attacker can induce errors during computation and exploit the faulty result to extract the key information embedded in the processor. Due to the design time issues weakness in the design is often revealed in the manufactured chips. Also because the post- manufacture …

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Dual-Function Neuron-Based External Controller For A Static Var Compensator, Ganesh K. Venayagamoorthy, Sandhya R. Jetti Apr 2008

Dual-Function Neuron-Based External Controller For A Static Var Compensator, Ganesh K. Venayagamoorthy, Sandhya R. Jetti

Electrical and Computer Engineering Faculty Research & Creative Works

The use of wide-area measurements for power system stabilization has recently been given a lot of attention by researchers and the power industry to avoid cascading failures and blackouts, such as the one in North America in August 2003. This paper presents the design of a nonlinear external damping controller based on wide-area measurements as inputs to a single dual-function neuron (DFN)-based controller. This DFN controller is specifically designed to enhance the damping characteristics of a power system over a wide range of operating conditions using an existing static var compensator (SVC) installation. The major advantage of the DFN controller …

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Modeling Of Substrate Noise Effects In Dynamic Cmos Circuits, Waleed K. Al-Assadi, S. Burugapalli, Sagar R. Gosavi Apr 2008

Modeling Of Substrate Noise Effects In Dynamic Cmos Circuits, Waleed K. Al-Assadi, S. Burugapalli, Sagar R. Gosavi

Electrical and Computer Engineering Faculty Research & Creative Works

The decrease in the feature size has led to the integration of both digital and analog circuits on the same silicon die which has led to many crosstalk issues. The crosstalk due to the substrate interactions also plagiarizes complete digital systems. This paper lays emphasis on this fact and because of the vulnerability of dynamic CMOS circuits to noise; a brief study of the effects of substrate variations on the performance of the dynamic CMOS circuits is carried out in this paper. The effects of substrate noise at very high frequencies (above 10 GHz) are also depicted in this paper. …

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Design And Fpga Prototyping Of A Flood Prediction System, Sandeep Gandla, Waleed K. Al-Assadi, Sahra Sedigh, Raghu A. R. Rao Apr 2008

Design And Fpga Prototyping Of A Flood Prediction System, Sandeep Gandla, Waleed K. Al-Assadi, Sahra Sedigh, Raghu A. R. Rao

Electrical and Computer Engineering Faculty Research & Creative Works

This paper explains the chip design of a flood prediction system based on piezoelectric pressure sensors, and its FPGA prototyping. The sensors are placed at different water levels and can dependably predict the occurrence of a flood. The main criteria considered in design of the system are low cost, low power consumption, ease of installation, autonomy, reliability, and most importantly, provision of early alerts. Predicting the flood before its actual occurrence can buy sufficient time for residents to evacuate nearby areas, preventing loss of life and property. The design has been prototyped on Altera's Cyclone DE2 FPGA board.

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Further Results On Frequency-Domain Channel Equalization For Single Carrier Underwater Acoustic Communications, Y. Rosa Zheng, Chengshan Xiao, Xin Liu, Wen-Bin Yang, T. C. Yang Apr 2008

Further Results On Frequency-Domain Channel Equalization For Single Carrier Underwater Acoustic Communications, Y. Rosa Zheng, Chengshan Xiao, Xin Liu, Wen-Bin Yang, T. C. Yang

Electrical and Computer Engineering Faculty Research & Creative Works

A frequency-domain channel equalization and phase correction method was proposed in a previous work published in Oceans'07 conference, in which 10^-4 BER performance was presented for fixed-to-fixed source/receiver channels. The method is improved by using minimum mean square error (MMSE) estimation in channel updates rather than least squares estimation. It is applied to moving-to-fixed channels in the AUVFest'07 ocean experiment where single-carrier wideband transmission was employed with quadrature phase shift keying modulation. The moving source channels exhibit higher Doppler shift and larger Doppler drift than the fixed-to-fixed channels. Therefore, the number of symbols required for initial phase estimation is increased …

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Design And Implementation Of Fpga Configuration Logic Block Using Asynchronous Semi-Static Ncl Circuits, Indira P. Dugganapally, Waleed K. Al-Assadi, Vijay Pillai, Scott C. Smith Apr 2008

Design And Implementation Of Fpga Configuration Logic Block Using Asynchronous Semi-Static Ncl Circuits, Indira P. Dugganapally, Waleed K. Al-Assadi, Vijay Pillai, Scott C. Smith

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes the design of a FPGA configurable logic block (CLB) using asynchronous semi-static NULL convention logic (NCL) Library. The proposed design uses three semi-static LLT's for implementing NCL logic functions. Each LLT can be configured to function as any one of the 27 fundamental NCL Semi-Static gates. The proposed CLB supports 10 inputs and three different outputs, each with resettable and inverting variations. The CLB has two modes: Configuration mode and Operation mode. The Static NCL FPGA CLB is simulated at the transistor level using the 1.8 V, 180 nm TSMC CMOS process.

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An Approach To Identifying The Biomechanical Differences Between Intercostal Cartilage In Subjects With Pectus Excavatum And Normals In Vivo: Reconstruction And Ct Registration, Zhenzhen Yan Apr 2008

An Approach To Identifying The Biomechanical Differences Between Intercostal Cartilage In Subjects With Pectus Excavatum And Normals In Vivo: Reconstruction And Ct Registration, Zhenzhen Yan

Electrical & Computer Engineering Theses & Dissertations

Pectus excavatum (PE) is a congenital chest wall deformity affecting the ribs and sternum and exhibiting a concave appearance in the anterior chest wall. In this thesis, we describe a study to investigate in vivo differences in the pectus excavatum rib cage and outline steps using normals and pectus patients data in developing models and methods to be used in carrying out the study. We propose methods to develop reconstructed models in order to enable proper registration between data collection points (DCPs) on the 3D CT rib cage model and CT skin surface model and registration between CT surrogate models …

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Improving Query Efficiency Of Multiresolution Data Aggregation For Analytical Exploration Of Large Relational Dataset, Yu-Ting Huang Apr 2008

Improving Query Efficiency Of Multiresolution Data Aggregation For Analytical Exploration Of Large Relational Dataset, Yu-Ting Huang

Masters Theses

Tree structures are developed to organize the data more efficiently by using fewer resources for searching records. This thesis investigates the tree's actual structure on the hard disk to see the influence of different kinds of structures on the tree building time and query execution time. In order to improve efficiency, one multi-file structure and two reorganization structures, BFS and DFS, are examined to achieve this goal. The results indicate that two reorganization structures on KDB-tree structure can significantly improve the query execution time in large data sets and multi-file structure can slightly improve the TPIE lover level building time.

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Fluorescent Si Nanoparticle-Based Electrode For Sensing Biomedical Substances, Gang Wang, Siu-Tung Yau, Kevin Mantey, Munir H. Nayfeh Apr 2008

Fluorescent Si Nanoparticle-Based Electrode For Sensing Biomedical Substances, Gang Wang, Siu-Tung Yau, Kevin Mantey, Munir H. Nayfeh

Electrical and Computer Engineering Faculty Publications

We have been studying the miniaturization of silicon crystals and the transition from the solid state to the atomistic state. We demonstrated the existence of “sweet spots” in cluster size in the range 1–3nm that have enhanced chemical, structural, and photo stability. The particles are produced by an electrochemical etching process as dispersion in liquid, and they are reconstituted in films, patterns, alloys, or spread on chips to produce super chips. Unlike bulk, these Si nanoparticle configurations have a spectacular ability to glow in distinct RGB colors. In this paper we describe an electrode sensor built by decorating metal or …

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Channel Estimation, Equalization And Phase Correction For Single Carrier Underwater Acoustic Communications, Jun Tao, Y. Rosa Zheng, Chengshan Xiao, Wen-Bin Yang, T. C. Yang Apr 2008

Channel Estimation, Equalization And Phase Correction For Single Carrier Underwater Acoustic Communications, Jun Tao, Y. Rosa Zheng, Chengshan Xiao, Wen-Bin Yang, T. C. Yang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we employ a time-domain channel estimation, equalization and phase correction scheme for single carrier single input multiple output (SIMO) underwater acoustic communications. In this scheme, Doppler shift, which is caused by relative motion between transducer (source) and hydrophones (receiver), is estimated and compensated in the received baseband signals. Then the channel is estimated using a small training block at the front of a transmitted data package, in which the data is artificially partitioned into consecutive data blocks. The estimated channel is utilized to equalize a block of received data, then the equalized data is processed by a …

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Design And Implementation Of Fpga Configuration Logic Block Using Asynchronous Static Ncl, Waleed K. Al-Assadi, T. Tammina, Scott C. Smith, Indira P. Dugganapally Apr 2008

Design And Implementation Of Fpga Configuration Logic Block Using Asynchronous Static Ncl, Waleed K. Al-Assadi, T. Tammina, Scott C. Smith, Indira P. Dugganapally

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes the design of a FPGA configurable logic block (CLB) using asynchronous static NULL convention logic (NCL) Library. The proposed design uses three static LUT's for implementing NCL logic functions. Each LUT can be configured to function as any one of the 27 fundamental NCL Static gates. The proposed CLB supports 10 inputs and three different outputs, each with resettable and inverting variations. The CLB has two modes: Configuration mode and operation mode. The static NCL FPGA CLB is simulated at the transistor level using the 1.8 V, 180 nm TSMC CMOS process.

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Applying Frequency-Domain Equalization To Code-Division Multiple Access And Transform-Domain Communications Systems, Alfred A. Tamayo Iii Mar 2008

Applying Frequency-Domain Equalization To Code-Division Multiple Access And Transform-Domain Communications Systems, Alfred A. Tamayo Iii

Theses and Dissertations

This research examined the theory and application of using orthogonal frequency division multiplexing (OFDM), or discrete multi-tone (DMT), frequency domain equalization (FEQ) with two communications systems that inherently possess unused carrier frequencies, or null-tones, in their respective transmission frequencies. The fundamental DMT-FEQ property relies on null-tones to equalize a non-ideal channel and mitigate the effects of interchannel interference (ICI), intersymbol interference (ISI), and noise. The two communications systems investigated were a Hadamard encoded code division multiple access (CDMA) communications system with up to 32 synchronous users and a transform domain communications system (TDCS) with only one user. Both communications systems …

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System For Reducing Stress Induced Effects Duringdetermination Of Fluid Optical Constants, Thomas E. Tiwald, John A. Woollam, Galen L. Pfeiffer, Blaine D. Johs, Craig M. Herzinger Mar 2008

System For Reducing Stress Induced Effects Duringdetermination Of Fluid Optical Constants, Thomas E. Tiwald, John A. Woollam, Galen L. Pfeiffer, Blaine D. Johs, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

A system for determination of optical constants of liquids, including provision for reducing stress induced effects while obtaining data.

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Direct, Object Brightness Estimation From Atmospheric Turbulence Degraded Images Using A New, High-Speed, Modified Phase Diversity Method, William W. Arrasmith Mar 2008

Direct, Object Brightness Estimation From Atmospheric Turbulence Degraded Images Using A New, High-Speed, Modified Phase Diversity Method, William W. Arrasmith

Electrical Engineering and Computer Science Faculty Publications

The well known phase diversity technique has long been used as a premier passive imaging method to mitigate the degrading effects of atmospheric turbulence on incoherent optical imagery. Typically, an iterative, slow method is applied that uses the Zernike basis set and 2-D Fourier transforms in the reconstruction process. In this paper, we demonstrate a direct method for estimating the un-aberrated object brightness from phase or phase difference estimates that 1) does not require the use of the Zernike basis set or the intermediate determination of the generalized pupil function, 2) directly determines the optical transfer function without the requirement …

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Real-Time Forward Urban Environment Perception For An Autonomous Ground Vehicle Using Computer Vision And Lidar, Christopher Richard Greco Mar 2008

Real-Time Forward Urban Environment Perception For An Autonomous Ground Vehicle Using Computer Vision And Lidar, Christopher Richard Greco

Theses and Dissertations

The field of autonomous vehicle research is growing rapidly. The Congressional mandate for the military to use unmanned vehicles has, in large part, sparked this growth. In conjunction with this mandate, DARPA sponsored the Urban Challenge, a competition to create fully autonomous vehicles that can operate in urban settings. An extremely important feature of autonomous vehicles, especially in urban locations, is their ability to perceive their environment. The research presented in this thesis is directed toward providing an autonomous vehicle with real-time data that efficiently and compactly represents its forward environment as it navigates an urban area. The information extracted …

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Securing Manets With Bitsi: Danger Theory And Mission Continuity, Marco Carvalho, Richard A. Ford, William H. Allen, Gerald A. Marin Mar 2008

Securing Manets With Bitsi: Danger Theory And Mission Continuity, Marco Carvalho, Richard A. Ford, William H. Allen, Gerald A. Marin

Electrical Engineering and Computer Science Faculty Publications

MANET (Mobile Ad hoc Network) environments are becoming increasingly important as potential users recognize the benefits of being able to create a functional network using little or no fixed infrastructure. Unfortunately, the very properties that provide such flexibility also cause significant complications in terms of security. The collaborative nature of the system combined with its continual state of flux requires solutions that are highly dynamic, and that can adapt to massive changes in system resources, traffic patterns and network topology. In this paper, we outline a new approach to MANET security called BITSI (the Biologically-Inspired Tactical Security Infrastructure). BITSI is …

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Design And Implementation Of An All-Digital Real-Time Underwater Acoustic Transceiver Using Digital Signal Processors, Fu-Sheng Lu, Ching-Hsiang Tseng, Bin-Chong Wu Mar 2008

Design And Implementation Of An All-Digital Real-Time Underwater Acoustic Transceiver Using Digital Signal Processors, Fu-Sheng Lu, Ching-Hsiang Tseng, Bin-Chong Wu

Journal of Marine Science and Technology–Taiwan

In this paper, an all-digital transceiver for real-time underwater acoustic (UWA) communications is developed using digital signal processors (DSPs). The design of the transceiver is based on the direct-sequence spread-spectrum (DS/SS) modulation scheme, in which the timing synchronization is efficiently achieved by employing a sliding correlator and a modified noncoherent delay-locked loop for code acquisition and tracking, respectively. In addition, an equal-gain combiner (EGC) and an adaptive decision-feedback equalizer (DFE) are included in the receiver to enhance its interference rejection capability under multipath fading environments. Several real-time UWA transmission tests are conducted in an experimental water tank to evaluate the …

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Mobile Free Space Optical Communication System, Xian Wang, Chi Yeh Hsu, Xiaomin Jin Mar 2008

Mobile Free Space Optical Communication System, Xian Wang, Chi Yeh Hsu, Xiaomin Jin

Electrical Engineering

The paper discusses a low power consumption, light weight and low cost 10MHz free-space optical communication (FSO). The system is designed for mounting on mobile platforms, with effective range of at least 50 meters. Light-Emitting Diodes (LEDs) and Laser diodes (LDs) are used in the transmitter for comparison for their relative performance in the system. The receiver features a beam splitter that feeds part of the data link optical signal to a quadrant photodetector and controls a tracking/stabilization system using microcontroller. Since almost all commercial FSO systems are mounted on fixed positions such as buildings, the paper explores the possibility …

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Wind/Rain Backscatter Modeling And Wind/Rain Retrieval For Scatterometer And Synthetic Aperture Radar, Congling Nie Mar 2008

Wind/Rain Backscatter Modeling And Wind/Rain Retrieval For Scatterometer And Synthetic Aperture Radar, Congling Nie

Theses and Dissertations

Using co-located space-borne satellite (TRMM PR, ESCAT on ERS 1/2) measurements, and numerical predicted wind fields (ECMWF), the sensitivity of C-band backscatter measurement to rain is evaluated. It is demonstrated that C-band radar backscatter can be significantly altered by rain surface perturbation, an effect that has been previously neglected. A low-order wind/rain backscatter model is developed that has inputs of surface rain rate, incidence angle, wind speed, wind direction, and azimuth angle. The wind/rain backscatter model is accurate enough for describing the total backscatter in raining areas with relatively low variance. Rain has a more significant impact on measurements at …

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Microfluidic Power Generation, Aaron J. Sprecher Mar 2008

Microfluidic Power Generation, Aaron J. Sprecher

Theses and Dissertations

This thesis includes the detailed mathematical calculations used to determine the feasibility of harnessing electrical energy from the blood flow through human capillaries. The designs are inspired by human physiology and well established electromagnetic energy harvesting techniques and the fabrication methods have been proposed for the various components of the device. The fabrication and the design of these components have also been extensively analyzed using calculations based on the governing principles of microfluidics, kinetics, and electromagnetics. The analysis has confirmed that this design can produce sufficient energy to power a MEMS device using non-standard materials and fabrication methods. The designs …

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Anti-Tamper Method For Field Programmable Gate Arrays Through Dynamic Reconfiguration And Decoy Circuits, Samuel J. Stone Mar 2008

Anti-Tamper Method For Field Programmable Gate Arrays Through Dynamic Reconfiguration And Decoy Circuits, Samuel J. Stone

Theses and Dissertations

As Field Programmable Gate Arrays (FPGAs) become more widely used, security concerns have been raised regarding FPGA use for cryptographic, sensitive, or proprietary data. Storing or implementing proprietary code and designs on FPGAs could result in the compromise of sensitive information if the FPGA device was physically relinquished or remotely accessible to adversaries seeking to obtain the information. Although multiple defensive measures have been implemented (and overcome), the possibility exists to create a secure design through the implementation of polymorphic Dynamically Reconfigurable FPGA (DRFPGA) circuits. Using polymorphic DRFPGAs removes the static attributes from their design; thus, substantially increasing the difficulty …

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Improvement Of Ecm Techniques Through Implementation Of A Genetic Algorithm, James D. Townsend Mar 2008

Improvement Of Ecm Techniques Through Implementation Of A Genetic Algorithm, James D. Townsend

Theses and Dissertations

This research effective effort develops the necessary interfaces between the radar signal processing components and an optimization routine, such as genetic algorithms, to develop Electronic Countermeasure (ECM) waveforms under a Hardware-in-the-Loop (HILS) architecture. The various ECM waveforms are stored in an ECM library, where an operator selects the desired function to use against a particular system. This optimization works with modular components, compared to previous research that embedded a genetic algorithm into the Range Gate Pull-off (RGPO) waveform optimization loop, which can be interchanged based upon the operator's desired hardware/ software testing setup. The ECM library's first entries contain the …

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Induction Machine Broken Bar And Stator Short-Circuit Fault Diagnostics Based On Three Phase Stator Current Envelopes, Aderiano M. Da Silva, Richard J. Povinelli, Nabeel Demerdash Mar 2008

Induction Machine Broken Bar And Stator Short-Circuit Fault Diagnostics Based On Three Phase Stator Current Envelopes, Aderiano M. Da Silva, Richard J. Povinelli, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

A new method for the fault diagnosis of a broken rotor bar and interturn short circuits in induction machines (IMs) is presented. The method is based on the analysis of the three-phase stator current envelopes of IMs using reconstructed phase space transforms. The signatures of each type of fault are created from the three-phase current envelope of each fault. The resulting fault signatures for the new so-called ldquounseen signalsrdquo are classified using Gaussian mixture models and a Bayesian maximum likelihood classifier. The presented method yields a high degree of accuracy in fault identification as evidenced by the given experimental results, …

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Output Feedback Controller For Operation Of Spark Ignition Engines At Lean Conditions Using Neural Networks, Jonathan B. Vance, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier Mar 2008

Output Feedback Controller For Operation Of Spark Ignition Engines At Lean Conditions Using Neural Networks, Jonathan B. Vance, Brian C. Kaul, Jagannathan Sarangapani, J. A. Drallmeier

Electrical and Computer Engineering Faculty Research & Creative Works

Spark ignition (SI) engines operating at very lean conditions demonstrate significant nonlinear behavior by exhibiting cycle-to-cycle bifurcation of heat release. Past literature suggests that operating an engine under such lean conditions can significantly reduce NO emissions by as much as 30% and improve fuel efficiency by as much as 5%-10%. At lean conditions, the heat release per engine cycle is not close to constant, as it is when these engines operate under stoichiometric conditions where the equivalence ratio is 1.0. A neural network controller employing output feedback has shown ability in simulation to reduce the nonlinear cyclic dispersion observed under …

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An Improved Snr Estimator For Speech Enhancement, Yao Ren, Michael T. Johnson Mar 2008

An Improved Snr Estimator For Speech Enhancement, Yao Ren, Michael T. Johnson

Dr. Dolittle Project: A Framework for Classification and Understanding of Animal Vocalizations

In this paper, we propose an MMSE a priori SNR estimator for speech enhancement. This estimator has similar benefits to the well-known decision-directed approach, but does not require an ad-hoc weighting factor to balance the past a priori SNR and current ML SNR estimate with smoothing across frames. Performance is evaluated in terms of estimation error and segmental SNR using the standard logSTSA speech enhancement method. Experimental results show that, in contrast with the decision-directed estimator and ML estimator, the proposed SNR estimator can help enhancement algorithms preserve more weak speech information and efficiently suppress musical noise.

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Wideband Smaller Unit-Cell Planar Ebg Structures And Their Application, M. Faisal Abedin, Mohammed Z. Azad, Mohammod Ali Mar 2008

Wideband Smaller Unit-Cell Planar Ebg Structures And Their Application, M. Faisal Abedin, Mohammed Z. Azad, Mohammod Ali

Faculty Publications

A new low-cost smaller unit-cell planar electromagnetic bandgap (ERG) structure operating at the lower GHz frequencies (below 6 GHz) is proposed. ERG structures based on this new geometry are designed on a number of commonly available substrates. Characteristics of such structures, such as bandgap and reflection phase profile are analyzed. a simple empirical model is proposed to predict the surface wave stopband frequency of the proposed ERG structure. Finally, a low-profile dipole antenna is designed and tested for operation on the ERG structure.

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Digital Signal Processing Leveraged For Intrusion Detection, Theodore J. Erickson Mar 2008

Digital Signal Processing Leveraged For Intrusion Detection, Theodore J. Erickson

Theses and Dissertations

This thesis describes the development and evaluation of a novel system called the Network Attack Characterization Tool (NACT). The NACT employs digital signal processing to detect network intrusions, by exploiting the Lomb-Scargle periodogram method to obtain a spectrum for sampled network traffic. The Lomb-Scargle method for generating a periodogram allows for the processing of unevenly sampled network data. This method for determining a periodogram has not yet been used for intrusion detection. The spectrum is examined to determine if features exist above a significance level chosen by the user. These features are considered an attack, triggering an alarm. Two traffic …

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Multi-Reference Frame Image Registration For Rotation, Translation, And Scale, Christopher S. Costello Mar 2008

Multi-Reference Frame Image Registration For Rotation, Translation, And Scale, Christopher S. Costello

Theses and Dissertations

This thesis investigates applications of multi-reference frame image registration for image sets with various translation, rotation, and scale combinations. It focuses on registration accuracy improvement over traditional pairwise registration, and also compares the quality of scene estimation from frame averaging. Three experiments are developed which use cross-correlation to estimate translation, the Radon transform to estimate translation and rotation, and the Fourier-Mellin transform to estimate translation, rotation, and scale. Results from applying multi-reference frame registration in these experiments show distinct improvements in both registration accuracy and quality of frame averaging compared to single-reference frame registration. Furthermore, it is shown that the …

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