Electrical and Computer Engineering Commons^™

An Electron‐Rich Calix[4]Arene‐Based Receptor With Unprecedented Binding Affinity For Nitric Oxide, Denan Wang, Lena V. Ivanova, Maxim V. Ivanov, Saber Mirzaei, Qadir K. Timerghazin, Scott A. Reid, Rajendra Rathore

Electrical and Computer Engineering Faculty Research and Publications

Calixarenes have found widespread application as building blocks for the design and synthesis of functional materials in host–guest chemistry. The ongoing desire to develop a detailed understanding of the nature of NO bonding to multichromophoric π‐stacked assemblies led us to develop an electron‐rich methoxy derivative of calix[4]arene (3), which we show exists as a single conformer in solution at ambient temperature. Here, we examine the redox properties of this derivative, generate its cation radical (3^+.) using robust chemical oxidants, and determine the relative efficacy of its NO binding in comparison with model calixarenes. We find …

Field Oriented Sliding Mode Control Of Surface-Mounted Permanent Magnet Ac Motors: Theory And Applications To Electrified Vehicles, Xin Wang, Max Reitz, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Permanent magnet ac motors have been extensively utilized for adjustable-speed traction motor drives, due to their inherent advantages including higher power density, superior efficiency and reliability, more precise and rapid torque control, larger power factor, longer bearing, and insulation life-time. Without any proportional-and-integral (PI) controllers, this paper introduces novel first- and higher-order field-oriented sliding mode control schemes. Compared with the traditional PI-based vector control techniques, it is shown that the proposed field oriented sliding mode control methods improve the dynamic torque and speed response, and enhance the robustness to parameter variations, modeling uncertainties, and external load perturbations. While both first- …

Impacts Of Operators’ Behavior On Reliability Of Power Grids During Cascading Failures, Zhuoyao Wang, Mahshid Rahnamay-Naeini, Joana M. Abreu, Rezoan A. Shuvro, Pankaz Das, Andrea Mammoli, Nasir Ghani, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

Human operators play a key role in the reliable operation of critical infrastructures. However, human operators may take actions that are far from optimum. This can be due to various factors affecting the operators' performance in time-sensitive and critical situations such as reacting to contingencies with significant monetary and social impacts. In this paper, an analytic framework is proposed based on Markov chains for modeling the dynamics of cascading failures in power grids. The model captures the effects of operators' behavior quantified by the probability of human error under various circumstances. In particular, the observations from historical data and information …

Multispecies Fruit Flower Detection Using A Refined Semantic Segmentation Network, Philipe A. Dias, Amy Tabb, Henry P. Medeiros

Electrical and Computer Engineering Faculty Research and Publications

In fruit production, critical crop management decisions are guided by bloom intensity, i.e., the number of flowers present in an orchard. Despite its importance, bloom intensity is still typically estimated by means of human visual inspection. Existing automated computer vision systems for flower identification are based on hand-engineered techniques that work only under specific conditions and with limited performance. This letter proposes an automated technique for flower identification that is robust to uncontrolled environments and applicable to different flower species. Our method relies on an end-to-end residual convolutional neural network (CNN) that represents the state-of-the-art in semantic segmentation. To enhance …

Parallel Implementation Of Facial Detection Using Graphics Processing Units, Russell Marineau

Master's Theses (2009 -)

This thesis proposes to study parallelization methods to improve the computational runtime of the popular Viola-Jones face detection algorithm. These methods employ multithreaded programming and CUDA programming approaches. The thesis provides a discussion of background information on all relevant topics, which is then followed by a presentation of the code architecture changes that are proposed. Specific implementation details are then discussed in more details followed by a discussion and comparison of results obtained through various tests. This thesis first begins by presenting a history and description of the Viola-Jones algorithm. Detailed explanations of each step in the process used to …

Obtaining Chemical Selectivity From A Single, Nonselective Sensing Film: Two-Stage Adaptive Estimation Scheme With Multiparameter Measurement To Quantify Mixture Components And Interferents, Karthick Sothivelr, Florian Bender, Fabien Josse Phd, Edwin E. Yaz, Antonio J. Ricco

Electrical and Computer Engineering Faculty Research and Publications

A new approach is reported to detect and quantify the members of a group of small-aromatic-molecule target analytes: benzene, toluene, ethylbenzene, and xylenes (BTEX), dissolved in water, in the presence of interferents, using only the data collected from a single polymer-coated SH-SAW (shear horizontal surface acoustic wave) device and a two-stage adaptive estimation scheme. This technique is composed of exponentially weighted recursive least-squares estimation (EW-RLSE) and a bank of Kalman filters (BKFs) and does not require any prior knowledge of the initial concentration range of the target analytes. The proposed approach utilizes the transient sensor response to sorption and/or desorption …

Stator Resistance Estimation Using Adaptive Estimation Via A Bank Of Kalman Filters, Alia R. Strandt, Andrew Strandt, Susan C. Schneider, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Accurate and efficient control of electric motors is dependent on knowledge of motor parameters such as the resistance and the inductance of the winding. However, these parameters are often unavailable to the control designer because they are dependent on the motor design and may change due to environmental effects such as temperature. An accurate real-time method to determine the values of these unknown parameters can improve motor performance over the entire operating range. In this work, a parameter estimation technique based on a bank of Kalman filters is used to adaptively estimate the motor winding resistance. Simulation results for a …

Coupled State-Dependent Riccati Equation Control For Continuous Time Nonlinear Mechatronics Systems, Xin Wang, Edwin E. Yaz, Susan C. Schneider

Electrical and Computer Engineering Faculty Research and Publications

This manuscript considers the coupled state-dependent Riccati equation approach for systematically designing nonlinear quadratic regulator and H _∞ control of mechatronics systems. The state-dependent feedback control solutions can be obtained by solving a pair of coupled state-dependent Riccati equations, guaranteeing nonlinear quadratic optimality with inherent stability property in combination with robust ℓ ₂ type of disturbance reduction. The derivation of this control strategy is based on Nash's game theory. Both of finite and infinite horizon control problems are discussed. An underactuated robotic system, Furuta rotary pendulum, is used to examine the effectiveness and robustness of this novel nonlinear control approach.

Dissipative Resilient Observer, M. Sami Fadali, Edwin E. Yaz

Electrical and Computer Engineering Faculty Research and Publications

Cybersecurity is a major concern for designers of control systems that can be directed against any of their components. Observers are an integral part of control systems that require state feedback. This paper considers an observer subject to errors in implementation or subject to cyberattacks. The errors and cyberattacks result in perturbations in the gain and in a finite-energy but unknown disturbance input. We obtain conditions for Q-S-R dissipativity and stability of the observer in the presence of the gain errors and disturbances in the form of linear matrix inequalities (LMIs). Three examples are presented to show how the LMIs …

Prior Day Effect In Forecasting Daily Natural Gas Flow From Monthly Data, Maral Fakoor, George F. Corliss, Ronald H. Brown

Electrical and Computer Engineering Faculty Research and Publications

Many needs exist in the energy industry where measurement is monthly yet daily values are required. The process of disaggregation of low frequency measurement to higher frequency values has been presented in this literature. Also, a novel method that accounts for prior-day weather impacts in the disaggregation process is presented, even though prior-day impacts are not directly recoverable from monthly data. Having initial daily weather and gas flow data, the weather and flow data are aggregated to generate simulated monthly weather and consumption data. Linear regression models can be powerful tools for parametrization of monthly/daily consumption models and will enable …

Apple Flower Detection Using Deep Convolutional Networks, Philipe A. Dias, Amy Tabb, Henry P. Medeiros

Electrical and Computer Engineering Faculty Research and Publications

To optimize fruit production, a portion of the flowers and fruitlets of apple trees must be removed early in the growing season. The proportion to be removed is determined by the bloom intensity, i.e., the number of flowers present in the orchard. Several automated computer vision systems have been proposed to estimate bloom intensity, but their overall performance is still far from satisfactory even in relatively controlled environments. With the goal of devising a technique for flower identification which is robust to clutter and to changes in illumination, this paper presents a method in which a pre-trained convolutional neural network …

Design Day Analysis - Forecasting Extreme Daily Natural Gas Demand, David Joseph Kaftan

Master's Theses (2009 -)

This work provides a framework for Design Day analysis. First, we estimate the temperature conditions which are expected to be colder than all but one day in N years. This temperature is known as the Design Day condition. Then, we forecast an upper bound on natural gas demand when temperature is at the Design Day condition. Natural gas distribution companies (LDCs) need to meet demand during extreme cold days. Just as bridge builders design for a nominal load, natural gas distribution companies need to design for a nominal temperature. This nominal temperature is the Design Day condition. The Design Day …

Search Methods For Mobile Manipulator Performance Measurement, Samuel Nana Yaw Amoako-Frimpong

Master's Theses (2009 -)

Mobile manipulators are a potential solution to the increasing need for additional flexibility and mobility in industrial robotics applications. However, they tend to lack the accuracy and precision achieved by fixed manipulators, especially in scenarios where both the manipulator and the autonomous vehicle move simultaneously. This thesis analyzes the problem of dynamically evaluating the positioning error of mobile manipulators. In particular, it investigates the use of Bayesian methods to predict the position of the end-effector in the presence of uncertainty propagated from the mobile platform. Simulations and real-world experiments are carried out to test the proposed method against a deterministic …

Comparative Study Of Different Sensor Array Designs Involving Plasticized Polymer Coatings For Btex Detection In Water, Nicholas Post

Master's Theses (2009 -)

Detection and quantification of benzene, toluene, ethylbenzene, and xylenes (BTEX) in liquid phase is of interest because of the significant public health hazards posed by these compounds. BTEX are volatile organic compounds (VOCs) commonly used as additives in gasoline. Shear horizontal surface acoustic wave (SH-SAW) devices have shown promise in liquid phase sensing applications and is used to address this problem. SH-SAW devices can be made chemically sensitive by depositing a polymer coating on the device surface. SH-SAW devices coated with commercially available polymers have shown modest sensitivity to BTEX compounds. However, there are few polymers which exhibit the properties …

Foreword Special Section On Electrical Contacts, Ronald A. Coutu Jr., Ravi Mahajan

Electrical and Computer Engineering Faculty Research and Publications

Welcome to the Special Topics Section dedicated to the 2016 Holm Conference on Electrical Contacts. This special section contains eight high-quality papers that comprehensively describe the state of the art and potential future directions for topics of great interest to our readers. The Editor-in-Chief (EIC), in consultation with the other EICs, Associate Editors (AEs), and domain experts, selects the topics for the special sections, and a Guest Editor or AE (GE/AE), who is a leading expert in the technical area, then directs the solicitation and peer review of the papers. In cases where the GE/AE is also an author, the …

Performance Comparison Of Phase Change Materials And Metal-Insulator Transition Materials For Direct Current And Radio Frequency Switching Applications, Protap Mahanta, Mohiuddin Munna, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Advanced understanding of the physics makes phase change materials (PCM) and metal-insulator transition (MIT) materials great candidates for direct current (DC) and radio frequency (RF) switching applications. In the literature, germanium telluride (GeTe), a PCM, and vanadium dioxide (VO₂), an MIT material have been widely investigated for DC and RF switching applications due to their remarkable contrast in their OFF/ON state resistivity values. In this review, innovations in design, fabrication, and characterization associated with these PCM and MIT material-based RF switches, have been highlighted and critically reviewed from the early stage to the most recent works. We initially …

Automatic Segmentation Of Trees In Dynamic Outdoor Environments, Amy Tabb, Henry P. Medeiros

Electrical and Computer Engineering Faculty Research and Publications

Segmentation in dynamic outdoor environments can be difficult when the illumination levels and other aspects of the scene cannot be controlled. Specifically in orchard and vineyard automation contexts, a background material is often used to shield a camera's field of view from other rows of crops. In this paper, we describe a method that uses superpixels to determine low texture regions of the image that correspond to the background material, and then show how this information can be integrated with the color distribution of the image to compute optimal segmentation parameters to segment objects of interest. Quantitative and qualitative experiments …

Do Nir Spectra Collected From Laboratory-Reared Mosquitoes Differ From Those Collected From Wild Mosquitoes?, Masabho Peter Milali, Maggy T. Sikulu-Lord, Samson Sifael Kiware, Floyd E. Dowell, Richard J. Povinelli, George F. Corliss

Electrical and Computer Engineering Faculty Research and Publications

Background

Near infrared spectroscopy (NIRS) is a high throughput technique that measures absorbance of specific wavelengths of light by biological samples and uses this information to classify the age of lab-reared mosquitoes as younger or older than seven days with an average accuracy greater than 80%. For NIRS to estimate ages of wild mosquitoes, a sample of wild mosquitoes with known age in days would be required to train and test the model. Mark-release-recapture is the most reliable method to produce wild-caught mosquitoes of known age in days. However, it is logistically demanding, time inefficient, subject to low recapture rates, …

Uncertainty Aware Mapping Of Embedded Systems For Reliability, Performance, And Energy, Wenkai Guan, Milad Ghorbani Moghaddam, Cristinel Ababei

Electrical and Computer Engineering Faculty Research and Publications

Duo to technology downscaling, embedded systems have increased in complexity and heterogeneity. Increasingly large process, voltage, and temperature variations negatively affect the design and optimization process of these systems. These factors contribute to increased uncertainties that in turn undermine the accuracy and effectiveness of traditional design approaches. In this paper, we formulate the problem of uncertainty aware mapping for multicore embedded systems as a multi-objective optimization problem. We present a solution to this problem that integrates uncertainty models as a new design methodology constructed with Monto Carlo and evolutionary algorithms. The methodology is uncertainty aware because it is able to …

Experimental Validation Of External Load Effects For Micro-Contacts Under Low Frequency, Low Amplitude Alternating Current (Ac) Test Conditions, Protap Mahanta, Ronald A. Coutu Jr., Dushyant Tomer

Electrical and Computer Engineering Faculty Research and Publications

The use of micro-contacts has been demonstrated in various radio frequency (RF) applications. However, the premature failure of such devices under alternating current (AC) operations is still a hurdle to further development. In this work, modified gray scale lithography is performed to fabricate two types of gold–gold (Au–Au) micro-contacts: hemispherical-planar and hemispherical-2D pyramid. The performance of these devices was investigated under low frequency, low amplitude AC conditions with external circuit loads. A custom-made experimental setup which uses various load configurations, controls the frequency of the applied voltage and modifies the cycle rate of switch operation to obtain the contact resistance …

Remote Vibration Estimation Using Displaced-Phase-Center Antenna Sar For Strong Clutter Environments, Justin B. Campbell, Francisco Pérez, Qi Wang, Balasubramaniam Santhanam, Ralf Dunkel, Armin W. Doerry, Thomas Atwood, Majeed M. Hayat

Electrical and Computer Engineering Faculty Research and Publications

It has been previously demonstrated that it is possible to perform remote vibrometry using synthetic aperture radar (SAR) in conjunction with the discrete fractional Fourier transform (DFrFT). Specifically, the DFrFT estimates the chirp parameters (related to the instantaneous acceleration of a vibrating object) of a slow-time signal associated with the SAR image. However, ground clutter surrounding a vibrating object introduces uncertainties in the estimate of the chirp parameter retrieved via the DFrFT method. To overcome this shortcoming, various techniques based on subspace decomposition of the SAR slow-time signal have been developed. Nonetheless, the effectiveness of these techniques is limited to …

Hybrid Sensorless Field Oriented And Direct Torque Control For Variable Speed Brushless Dc Motors, Kellen Carey

Master's Theses (2009 -)

The objective of this thesis is to design a hybrid sensorless closed-loop motor controller using a combination of Field-Oriented Control (FOC) and Direct Torque Control (DTC) for brushless DC motors used in multi-rotor aerial vehicles. The primary challenge is the wide range of desired working speeds, which can quickly vary from low speed to high speed. For this range, the control approach must be efficient, effective, and low-cost in order to provide fast response times during initial startup, steady-state, and transient operation. Additional design challenges include minimal response time to desired speed changes and small steady-state speed errors. Finally, the …

An Unsupervised Cluster: Learning Water Customer Behavior Using Variation Of Information On A Reconstructed Phase Space, Michele Rae Bizub Malinowski

Dissertations (1934 -)

The unsupervised clustering algorithm described in this dissertation addresses the need to divide a population of water utility customers into groups based on their similarities and differences, using only the measured flow data collected by water meters. After clustering, the groups represent customers with similar consumption behavior patterns and provide insight into ‘normal’ and ‘unusual’ customer behavior patterns. This research focuses upon individually metered water utility customers and includes both residential and commercial customer accounts serviced by utilities within North America. The contributions of this dissertation not only represent a novel academic work, but also solve a practical problem for …

Analysis Of Sensor Signals For Online Detection Of Hydrocarbons In Liquids In The Presence Of Interferents, Karthick Sothivelr

Dissertations (1934 -)

Current applicability of many chemical sensors is limited due to the lack of adequate selectivity to enable real-world applications. Often, the chemically sensitive element of the sensor is only partially selective to any specific target analyte, potentially giving rise to low probability of detection. Other challenges include the need to identify and quantify the target analytes in a mixture, especially in the presence of non-target interferents. In this dissertation, to enhance the selectivity of the sensor, analysis of sensor signals for detection and quantification of mixtures of hydrocarbon compounds in liquids in the presence of interferents using estimation theory and …

Investigation Of Lstm Based Prediction For Dynamic Energy Management In Chip Multiprocessors, Milad Ghorbani Moghaddam, Wenkai Guan, Cristinel Ababei

Electrical and Computer Engineering Faculty Research and Publications

In this paper, we investigate the effectiveness of using long short-term memory (LSTM) instead of Kalman filtering to do prediction for the purpose of constructing dynamic energy management (DEM) algorithms in chip multi-processors (CMPs). Either of the two prediction methods is employed to estimate the workload in the next control period for each of the processor cores. These estimates are then used to select voltage-frequency (VF) pairs for each core of the CMP during the next control period as part of a dynamic voltage and frequency scaling (DVFS) technique. The objective of the DVFS technique is to reduce energy consumption …

Foreword: Special Section On Electrical Contacts, Ronald A. Coutu Jr., Ravi Mahajan

Electrical and Computer Engineering Faculty Research and Publications

Welcome to the Special Topics Section dedicated to the 2016 Holm Conference on Electrical Contacts. This Special Section contains six high-quality papers that comprehensively describe the state of the art and potential future directions for topics of great interest to our readers. The Editor-in-Chief (EIC), in consultation with the other EICs, Associate Editors (AEs), and domain experts, selects the topics for the Special Sections, and a Guest Editor or AE (GE/AE), who is a leading expert in the technical area, and then directs the solicitation and peer review of the papers. In cases where the GE/AE is also an author, …

H.264 Video Decoder Implemented On Fpgas Using 3×3 And 2×2 Networks-On-Chip, Ian Barge, Cristinel Ababei

Electrical and Computer Engineering Faculty Research and Publications

In this paper, we present the design and verification of the H.264 video decoder algorithm on FPGAs. The primary difference compared to previously reported designs is that the communication between the decoder modules is done via a network-on-chip in our case. The proposed design is a complete system level hardware design described in VHDL and Verilog. We report experimental results for two different implementations. The first implementation uses a 3×3 network-on-chip and is validated on the DE4 development board, which uses Altera's Stratix IV GX FPGA chip. The second implementation uses a 2×2 network-on-chip and is validated on the Cyclone …

Electronically Tuned Phase Transition In Germanium Telluride (Gete) Cells For Memory And Rf Switch Applications, Dushyant Tomer, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Germanium telluride (GeTe) is a phase change material that undergoes an amorphous to crystalline transition upon heating to ~ 200oC. This transition is reversible in nature and results in ~ six orders of magnitude difference in GeTe resistivity which makes it a suitable candidate for data storage and other functional devices. In this work, micro-size phase change test cells were fabricated by RF sputtering GeTe thin films onto silicon (Si) wafers and Si wafers coated with silicon dioxide (SiO2), silicon nitride (Si3N4), and alumina (Al2O3) films. Two different heating methods, conductive and electrical (i.e. Joule heating), were applied to induce …

Analytical Formulas For Mean Gain And Excess Noise Factor In Inas Avalanche Photodiodes, Erum Jamil, Majeed M. Hayat, Gordon A. Keeler

Electrical and Computer Engineering Faculty Research and Publications

It has been known that McIntyre's local multiplication theory for avalanche photodiodes (APDs) does not fully explain the experimental results for single-carrier InAs APDs, which exhibit excess noise factor values below 2. While it has been established that the inclusion of the dead-space effect in the nonlocal multiplication theory resolves this discrepancy, no closed-form formulas for the mean gain and excess noise factor have been specialized to InAs APDs in a nonlocal setting. Upon utilizing prior analytical formulation of single-carrier avalanche multiplication based on age-dependent branching theory in conjunction with nonlocal ionization coefficients and thresholds for InAs, closed-form solutions of …

A Phase Change Material For Reconfigurable Circuit Applications, Dushyant Tomer, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

The large resistance contrast between amorphous and crystalline states of phase change materials (PCM) makes them a promising candidate for data-storage applications. Germanium telluride (GeTe), an early member of the PCM family, shows ~6 orders of magnitude difference in resistivity upon phase transition. In this paper, two different heating methods, direct (Joule) and indirect thermal heating, were applied to induce a phase transition in vertical and horizontal GeTe resistors. In the electrical measurements, it was observed that thermal heating produces a two orders of magnitude larger difference in GeTe resistivity that the Joule heating, irrespective of the resistor’s geometry and …