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Electrical Engineering Faculty Publications

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Full-Text Articles in Engineering

Identifying Patients With Coronary Artery Disease Using Rest And Exercise Seismocardiography, Parastoo Dehkordi, Erwin P. Bauer, Kouhyar Tavakolian, Vahid Zakeri, Andrew P. Blaber, Farzad Khosrow-Khavar Sep 2019

Identifying Patients With Coronary Artery Disease Using Rest And Exercise Seismocardiography, Parastoo Dehkordi, Erwin P. Bauer, Kouhyar Tavakolian, Vahid Zakeri, Andrew P. Blaber, Farzad Khosrow-Khavar

Electrical Engineering Faculty Publications

Coronary artery disease (CAD) is the most common cause of death globally. Patients with suspected CAD are usually assessed by exercise electrocardiography (ECG). Subsequent tests, such as coronary angiography and coronary computed tomography angiography (CCTA) are performed to localize the stenosis and to estimate the degree of blockage. The present study describes a non-invasive methodology to identify patients with CAD based on the analysis of both rest and exercise seismocardiography (SCG). SCG is a non-invasive technology for capturing the acceleration of the chest induced by myocardial motion and vibrations. SCG signals were recorded from 185 individuals at rest and immediately …

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Relationship Between Ischemic Stroke And Pulse Rate Variability As A Surrogate Of Heart Rate Variability, Ajay K. Verma, Parshuram M. Aarotale, Parastoo Dehkordi, Jau-Shin Lou, Kouhyar Tavakolian Jul 2019

Relationship Between Ischemic Stroke And Pulse Rate Variability As A Surrogate Of Heart Rate Variability, Ajay K. Verma, Parshuram M. Aarotale, Parastoo Dehkordi, Jau-Shin Lou, Kouhyar Tavakolian

Electrical Engineering Faculty Publications

Autonomic reflex ascertains cardiovascular homeostasis during standing. Impaired autonomic reflex could lead to dizziness and falls while standing; this is prevalent in stroke survivors. Pulse rate variability (PRV) has been utilized in the literature in lieu of heart rate variability (HRV) for ambulatory and portable monitoring of autonomic reflex predominantly in young, healthy individuals. Here, we compared the PRV with gold standard HRV for monitoring autonomic reflex in ischemic stroke survivors. Continuous blood pressure and electrocardiography were acquired from ischemic stroke survivors (64 ± 1 years) and age-matched controls (65 ± 2 years) during a 10-minute sit-to-stand test. Beat-by-beat heart …

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A Printed Wearable Dual-Band Antenna For Wireless Power Transfer, Mohammad Haerinia, Sima Noghanian Apr 2019

A Printed Wearable Dual-Band Antenna For Wireless Power Transfer, Mohammad Haerinia, Sima Noghanian

Electrical Engineering Faculty Publications

In this work, a dual-band printed planar antenna, operating at two ultra-high frequency bands (2.5 GHz/4.5 GHz), is proposed for wireless power transfer for wearable applications. The receiving antenna is printed on a Kapton polyimide-based flexible substrate, and the transmitting antenna is on FR-4 substrate. The receiver antenna occupies 2.1 cm2 area. Antennas were simulated using ANSYS HFSS software and the simulation results are compared with the measurement results.

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Determining The Respiratory State From A Seismocardiographic Signal - A Machine Learning Approach, Christian Ulrich, Martin Jensen, Rolf Oberlin, Kouhyar Tavakolian, Farzad Khosrow-Khavar, Andrew Blaber, Kasper Sørensen, Samuel Schmidt Sep 2018

Determining The Respiratory State From A Seismocardiographic Signal - A Machine Learning Approach, Christian Ulrich, Martin Jensen, Rolf Oberlin, Kouhyar Tavakolian, Farzad Khosrow-Khavar, Andrew Blaber, Kasper Sørensen, Samuel Schmidt

Electrical Engineering Faculty Publications

Seismocardiography (SCG) is a non-invasive method for measurement of vibrations on the chest wall originating from the heart. Respiration changes the morphology of the SCG-signal and analyzing these changes could improve the diagnostic value of SCG. This study aimed to determine the nasal respiration signal amplitude at mitral closure (MC) and aortic opening (AO) using SCG features. The three proposed methods for this were multiple regression analysis (MRA), support vector regression (SVR), and a neural network (NN). SCG, Electrocardiography and nasal-catheter flow signals were acquired from 18 healthy subjects (age 29± 6). SCG-signal fiducial points were used as features and …

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Vertical Ground Reaction Force Marker For Parkinson’S Disease, Md Nafiul Alam, Amanmeet Garg, Tamanna Tabassum Khan Munia, Reza Fazel-Rezai, Kouhyar Tavakolian Jul 2018

Vertical Ground Reaction Force Marker For Parkinson’S Disease, Md Nafiul Alam, Amanmeet Garg, Tamanna Tabassum Khan Munia, Reza Fazel-Rezai, Kouhyar Tavakolian

Electrical Engineering Faculty Publications

Parkinson’s disease (PD) patients regularly exhibit abnormal gait patterns. Automated differentiation of abnormal gait from normal gait can serve as a potential tool for early diagnosis as well as monitoring the effect of PD treatment. The aim of current study is to differentiate PD patients from healthy controls, on the basis of features derived from plantar vertical ground reaction force (VGRF) data during walking at normal pace. The current work presents a comprehensive study highlighting the efficacy of different machine learning classifiers towards devising an accurate prediction system. Selection of meaningful feature based on sequential forward feature selection, the swing …

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Comparison Of Autonomic Control Of Blood Pressure During Standing And Artificial Gravity Induced Via Short-Arm Human Centrifuge, Ajay K. Verma, Da Xu, Michelle Bruner, Amanmeet Garg, Nandu Goswami, Andrew P. Blaber, Kouhyar Tavakolian Jun 2018

Comparison Of Autonomic Control Of Blood Pressure During Standing And Artificial Gravity Induced Via Short-Arm Human Centrifuge, Ajay K. Verma, Da Xu, Michelle Bruner, Amanmeet Garg, Nandu Goswami, Andrew P. Blaber, Kouhyar Tavakolian

Electrical Engineering Faculty Publications

Autonomic control of blood pressure is essential toward maintenance of cerebral perfusion during standing, failure of which could lead to fainting. Long-term exposure to microgravity deteriorates autonomic control of blood pressure. Consequently, astronauts experience orthostatic intolerance on their return to gravitational environment. Ground-based studies suggest sporadic training in artificial hypergravity can mitigate spaceflight deconditioning. In this regard, short-arm human centrifuge (SAHC), capable of creating artificial hypergravity of different g-loads, provides an auspicious training tool. Here, we compare autonomic control of blood pressure during centrifugation creating 1-g and 2-g at feet with standing in natural gravity. Continuous blood pressure was acquired …

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Crumpling Effects And Specific Absorption Rates Of Flexible Amc Integrated Antennas, Sima Noghanian, Ala Alemaryeen Mar 2018

Crumpling Effects And Specific Absorption Rates Of Flexible Amc Integrated Antennas, Sima Noghanian, Ala Alemaryeen

Electrical Engineering Faculty Publications

This study presents the design of a wearable textile-based monopole antenna integrated with a flexible artificial magnetic conductor (AMC). The proposed design covers the industrial, scientific, and medical 2.45 GHz band. An AMC reflector is utilised to isolate the human body from undesired electromagnetic radiation and to improve the antenna radiation characteristics. A monopole antenna was backed with an AMC reflector and tested in free space and on human body models. The inclusion of an AMC reflector increases the front-to-back ratio and antenna gain in free space. On the human body models, the AMC antenna provides stable performance and a …

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Hybrid Inductive Power Transfer And Wireless Antenna System For Biomedical Implanted Devices, Reem Shadid, Mohammad Haerinia, Sayan Roy, Sima Noghanian Jan 2018

Hybrid Inductive Power Transfer And Wireless Antenna System For Biomedical Implanted Devices, Reem Shadid, Mohammad Haerinia, Sayan Roy, Sima Noghanian

Electrical Engineering Faculty Publications

In this paper, we present a hybrid system consisting of a novel microstrip antenna that can be designed to resonate at various frequencies within the ultra-high frequency (UHF) band (e.g., 415 MHz, 905 MHz, and 1300 MHz), combined with a pair of high frequency (HF) coils (13.56 MHz). The system is designed to be fabricated on an FR4 substrate layer, and it provides a compact solution for simultaneous wireless power transfer (WPT) and multi-band wireless communication, to be utilized in implanted medical devices. The external antenna/coil combination (EX) will be located outside the body on the skin layer. The EX …

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Application Of P300 Event-Related Potential In Brain-Computer Interface, Ali Raider, Reza Fazel-Rezai Nov 2017

Application Of P300 Event-Related Potential In Brain-Computer Interface, Ali Raider, Reza Fazel-Rezai

Electrical Engineering Faculty Publications

The primary purpose of this chapter is to demonstrate one of the applications of P300 event-related potential (ERP), i.e., brain-computer interface (BCI). Researchers and students will find the chapter appealing with a preliminary description of P300 ERP. This chapter also appreciates the importance and advantages of noninvasive ERP technique. In noninvasive BCI, the P300 ERPs are extracted from brain electrical activities [electroencephalogram (EEG)] as a signature of the underlying electrophysiological mechanism of brain responses to the external or internal changes and events. As the chapter proceeds, topics are covered on more relevant scholarly works about challenges and new directions in …

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Non-Linear Heart Rate And Blood Pressure Interaction In Response To Lower-Body Negative Pressure, Ajay K. Verma, Da Xu, Amanmeet Garg, Anita T. Cote, Andrew P. Blaber, Kouhyar Tavakolian Oct 2017

Non-Linear Heart Rate And Blood Pressure Interaction In Response To Lower-Body Negative Pressure, Ajay K. Verma, Da Xu, Amanmeet Garg, Anita T. Cote, Andrew P. Blaber, Kouhyar Tavakolian

Electrical Engineering Faculty Publications

Early detection of hemorrhage remains an open problem. In this regard, blood pressure has been an ineffective measure of blood loss due to numerous compensatory mechanisms sustaining arterial blood pressure homeostasis. Here, we investigate the feasibility of causality detection in the heart rate and blood pressure interaction, a closed-loop control system, for early detection of hemorrhage. The hemorrhage was simulated via graded lower-body negative pressure (LBNP) from 0 to -40 mmHg. The research hypothesis was that a significant elevation of causal control in the direction of blood pressure to heart rate (i.e., baroreflex response) is an early indicator of central …

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A Software Based Smart Grid Framework For Automated Decision On Resource Allocation, Topological Control Using Omnet++, Eric Horton, Prakash Ranganathan Oct 2017

A Software Based Smart Grid Framework For Automated Decision On Resource Allocation, Topological Control Using Omnet++, Eric Horton, Prakash Ranganathan

Electrical Engineering Faculty Publications

The futuristic smart grid require creative architectures for Information and Communication technologies (ICT) networks. One such architecture must need some sort of topological control for the next generation grid. To assess architectural impact and effectiveness, simulation models are important. Communication networks are expected to be tightly coupled-integrated element for smart grid systems. The co-existence of communication and control and their joint operation necessitate accurate modeling of communication events. While at the first glance, it is tempting to model the communication network as a black box that introduces delay/s between its input and output, the complex interactions among grid network and …

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Gait And Tremor Assessment For Patients With Parkinson’S Disease Using Wearable Sensors, Shyam V. Perumal, Ravi Sankar Oct 2016

Gait And Tremor Assessment For Patients With Parkinson’S Disease Using Wearable Sensors, Shyam V. Perumal, Ravi Sankar

Electrical Engineering Faculty Publications

Typically, subjects with Parkinson’s disease (PD) display instances of tremor at an early stage of the disease and later on develop gait impairments and postural instability. In this research, we have investigated the effect of using both gait and tremor features for an early detection and monitoring of PD. Various features were extracted from the data collected from the wearable sensors and further analyzed using statistical analysis and machine learning techniques to find the most significant features that would best distinguish between the two groups: subjects with PD and healthy control subjects. The analysis of our results shows that the …

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On Quality-Of-Service Provisioning In Ieee 802.11ax Wlans, Der-Jiunn Deng, Shao-Yu Lien, Jordan Lee, Kwang-Cheng Chen Aug 2016

On Quality-Of-Service Provisioning In Ieee 802.11ax Wlans, Der-Jiunn Deng, Shao-Yu Lien, Jordan Lee, Kwang-Cheng Chen

Electrical Engineering Faculty Publications

A revolutionary effort to seek fundamental improvement of 802.11, known as IEEE 802.11ax, has been approved to deliver the next-generation wireless local area network (WLAN) technologies. In WLANs, medium access control protocol is the key component that enables efficient sharing the common radio channel while satisfying the quality of service (QoS) requirements for multimedia applications. With the new physical layer design and subsequent new medium access control functions under more demands on QoS and user experience, in this paper, we first survey the QoS support in legacy 802.11. Then, we summarize the IEEE 802.11ax standardization activities in progress and present …

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Incorporating Energy Related Concepts Into Ee And Cs Laboratory Work And Coursework, Jack Adams, Christopher S. Stuetzle Apr 2016

Incorporating Energy Related Concepts Into Ee And Cs Laboratory Work And Coursework, Jack Adams, Christopher S. Stuetzle

Electrical Engineering Faculty Publications

During the course of this interdisciplinary effort, members of the Electrical Engineering (EE) and Computer Science (CS) departments collaborated on energy related curricular efforts. Initially work was carried out to develop and utilize an inexpensive, open-source system for measuring, storing, and displaying energy related data from across campus. Hardware and software components chosen were open source or free for educational use. A low power Linux server was utilized. The LAN-enabled Arduinos included sensors to measure energy related quantities such as power and temperature. EE and CS students were engaged in various aspects of the project – EE students focused on …

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A Tool For Beamforming And Real-Time Link Budget Analysis In Aeronautical Communications Using Kinematics, M. Cenk Erturk, Yasin Aksan Jan 2016

A Tool For Beamforming And Real-Time Link Budget Analysis In Aeronautical Communications Using Kinematics, M. Cenk Erturk, Yasin Aksan

Electrical Engineering Faculty Publications

Aeronautical Communication (AC) systems are likely to be a part of future tiered communication network structures. Therefore maintaining a robust AC link with a minimum power burden on the host platform has a critical importance. In this paper, we analyze the AC systems from a link budget analysis point of view and define the requirements for the parameters of link budget with an emphasize on antenna gains. First, we study the link budget analysis in an AC system. Then, we present a mathematical framework to provide an end-to-end link budget analysis utilizing the platform kinematics. Finally, we present the numerical …

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Fourth-Order Contour Mode Zno-On-Soi Disk Resonators For Mass Sensing Applications, Ivan Rivera, Adrian Avila, Jing Wang Apr 2015

Fourth-Order Contour Mode Zno-On-Soi Disk Resonators For Mass Sensing Applications, Ivan Rivera, Adrian Avila, Jing Wang

Electrical Engineering Faculty Publications

In this work, we have investigated the design, fabrication and testing of ZnO-on-SOI fourth-order contour mode disk resonators for mass sensing applications. This study aims to unveil the possibility for real-time practical mass sensing applications by using high-Q ZnO-on-SOI contour-mode resonators while taking into account their unique modal characteristics. Through focused ion beam (FIB) direct-write metal deposition techniques, the effects of localized mass loading on the surface of three extensional mode devices have been investigated. Ten microfabricated 40 mm-radius disk resonators, which all have a 20 mm-thick silicon device layer and 1 mm-thick ZnO transducer layer but varied anchor widths …

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Visualization Of 4d Q2psk And Ce Q2psk In Ideal Bandlimited Channels, Milton I. Quinteros, Edit J. Kaminsky, Kenneth V. Cartwright Jan 2015

Visualization Of 4d Q2psk And Ce Q2psk In Ideal Bandlimited Channels, Milton I. Quinteros, Edit J. Kaminsky, Kenneth V. Cartwright

Electrical Engineering Faculty Publications

This paper presents new visualization techniques for 4D Quadrature-Quadrature Phase Shift Keying (Q2PSK), Saha’s Constant Envelope (CE) Q2PSK, and Cartwright’s CEQ2PSK in ideal bandlimited channels. The signal diagrams analyzed are: time-signal eye patterns for 4D passband signals, 2D complex trajectory diagrams of baseband signals, and time-signal eye patterns for the 1D outputs of the baseband matched filter. These methods may be applied to other multidimensional modulation systems to obtain insight into the effects of noise, interference, and channel filtering.

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A Further Look At Capacitors In Complex Arrangements, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky Dec 2014

A Further Look At Capacitors In Complex Arrangements, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky

Electrical Engineering Faculty Publications

Recently, a previous contributor showed how the delta-wye conversion may be applied to find the equivalent capacitance of five capacitors arranged in a bridge configuration. In fact, that contributor gave an algorithm for this purpose which showed that the equivalent capacitance depends upon all five capacitors. However, in this paper, we point out that there is a special case where the equivalent capacitance does not depend upon one of the five capacitors.

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Finding The Minimum Input Impedance Of A Second-Order Twofold-Gain Sallen-Key Low-Pass Filter Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky Dec 2014

Finding The Minimum Input Impedance Of A Second-Order Twofold-Gain Sallen-Key Low-Pass Filter Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

We derive an expression for the input complex impedance of a Sallen-Key second-order low-pass filter of twofold gain as a function of the natural frequency ωo and the quality factor Q. From this expression, it is shown that the filter behaves like a Frequency Dependent Negative Resistance (FDNR) element for low frequencies and as a single resistor at high frequencies. Furthermore, the minimum input impedance magnitude is found without using calculus. We discovered that the minimum input impedance magnitude is inversely proportional to Q and can be substantially less than its high-frequency value. Approximations to the minimum input impedance and …

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Finding The Maximum And Minimum Magnitude Responses (Gains) Of Third-Order Filters Without Calculus, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky Dec 2013

Finding The Maximum And Minimum Magnitude Responses (Gains) Of Third-Order Filters Without Calculus, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky

Electrical Engineering Faculty Publications

The maximum and minimum gains (with respect to frequency) of third-order low-pass and high-pass filters are derived without using calculus. Our method uses the little known fact that extrema of cubic functions can easily be found by purely algebraic means. PSpice simulations are provided that verify the theoretical results.

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Finding The Minimum Input Impedance Of A Second-Order Unity-Gain Sallen-Key Low-Pass Filter Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky Dec 2013

Finding The Minimum Input Impedance Of A Second-Order Unity-Gain Sallen-Key Low-Pass Filter Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

We derive an expression for the input complex impedance of a Sallen-Key second-order low-pass filter of unity gain as a function of the natural frequency , o  quality factor Q and the ratio of the resistors of the filter. From this expression, it is shown that the filter behaves like a single capacitor for low frequencies and as a single resistor at high frequencies. Furthermore, the minimum input impedance magnitude is found without using calculus. We discovered that the minimum input impedance magnitude is inversely proportional to Q and can be substantially less than its highfrequency value. Approximations to …

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Complex Reflection Coefficients Of P- And S-Polarized Light At The Pseudo-Brewster Angle Of A Dielectric–Conductor Interface, Rasheed M.A. Azzam Sep 2013

Complex Reflection Coefficients Of P- And S-Polarized Light At The Pseudo-Brewster Angle Of A Dielectric–Conductor Interface, Rasheed M.A. Azzam

Electrical Engineering Faculty Publications

The complex Fresnel reflection coefficients rp and rs of p- and s-polarized light and their ratio ρ = rp/rs at the pseudo-Brewster angle (PBA) φpBof a dielectric-conductor interface are evaluated for all possible values of the complex relative dielectric function Ε = |Ε| exp(-jθ) = Εr - jΕi, Εi > 0 that share the same φpB. Complex-plane trajectories of rp, rs, and ρ at the PBA are presented at discrete values of φpB from 5° to 85° in equal steps of 5° as θ is increased from 0° to 180°. It is shown that for φpB > 70° (high-reflectance metals in the …

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A Review Of P300, Ssvep, And Hybrid P300/Ssvep Brain-Computer Interface Systems, Reza Fazel-Rezai, Setare Amiri, Ahmed Rabbi, Leila Azinfar Jun 2013

A Review Of P300, Ssvep, And Hybrid P300/Ssvep Brain-Computer Interface Systems, Reza Fazel-Rezai, Setare Amiri, Ahmed Rabbi, Leila Azinfar

Electrical Engineering Faculty Publications

No abstract provided.

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Study Of The Effects Of Changing Physiological Conditions On Dielectric Properties Of Breast Tissues, Abas Sabouni, Camerin Hahn, Sima Noghanian, Edward Sauter, Tim Weiland Jan 2013

Study Of The Effects Of Changing Physiological Conditions On Dielectric Properties Of Breast Tissues, Abas Sabouni, Camerin Hahn, Sima Noghanian, Edward Sauter, Tim Weiland

Electrical Engineering Faculty Publications

This paper addresses the changes in the physical characteristics (temperature and water/blood content) of breast tissue under different physiological conditions. We examined ex vivo specimens of breast tissue excised at the time of surgery to study the effects of physiological conditions on dielectric properties. We observed that the dielectric properties strongly depend on tissue physiological state. When the biological tissues undergo physiological changes, such as those due to disease or those induced by external changes such as variations in the environmental temperature, the microscopic processes deviate from their normal state and impact the overall dielectric properties. This suggests that microwave …

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Finding The Maximum Magnitude Response (Gain) Of Second-Order Filters Without Calculus, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky Dec 2012

Finding The Maximum Magnitude Response (Gain) Of Second-Order Filters Without Calculus, Kenneth V. Cartwright, Patrick Russell, Edit J. Kaminsky

Electrical Engineering Faculty Publications

The maximum gain (with respect to frequency) of second-order filters such as low-pass, high-pass, band-pass, low-pass notch and high-pass notch filters is derived without using calculus. Our method uses the fact that the square of the magnitude response (gain) for these filters can be written as a positive constant divided by a quadratic function of frequency. Hence, the gain is maximized when the denominator of the gain is minimized, which is easily achieved without calculus, as the denominator is parabolic.

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Determining The Maximum Or Minimum Impedance Of A Special Parallel Rlc Circuit Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky Mar 2012

Determining The Maximum Or Minimum Impedance Of A Special Parallel Rlc Circuit Without Calculus, Kenneth V. Cartwright, Edit J. Kaminsky

Electrical Engineering Faculty Publications

We show that the maximum or minimum impedance of a special parallel RLC studied in a previous paper can be found analytically, without using calculus. In fact, we show that the maximum or minimum value occurs when the driving frequency  is equal to o 1/ LC , a fact that was determined graphically in that previous paper. Furthermore, we show that either the maximum or minimum value is given by     2 2 R  1  3 ,where   L/C / R. Also, for the minimum impedance   2 min Z  R …

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Excessive Grain Boundary Conductivity Of Spin-Spray Deposited Ferrite/Non-Magnetic Multilayer, Yun Xing, J. Myers, Ogheneyunume Obi, Nian X. Sun, Yan Zhuang Feb 2012

Excessive Grain Boundary Conductivity Of Spin-Spray Deposited Ferrite/Non-Magnetic Multilayer, Yun Xing, J. Myers, Ogheneyunume Obi, Nian X. Sun, Yan Zhuang

Electrical Engineering Faculty Publications

Magnetic materials with a high self-biased ferromagnetic resonance (FMR) frequency and low electrical conductivity hold great potential for RF/microwave devices. In this work, ferrite film consisting of Fe3O4 (1.2 mu m)/photoresist (60 nm)/Fe3O4 (1.2 mu m) was deposited at 90 degrees C via spin spray deposition. Broadband impedance imaging with nanometer spatial resolution was recorded by using scanning microwave microscopy. Compared to a reference sample, it turned out that the grain boundary appeared to be more conductive than the grain.

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Circular And Near-Circular Polarization States Of Evanescent Monochromatic Light Fields In Total Internal Reflection, R. M. A Azzam Nov 2011

Circular And Near-Circular Polarization States Of Evanescent Monochromatic Light Fields In Total Internal Reflection, R. M. A Azzam

Electrical Engineering Faculty Publications

Conditions for the production of near-circular polarization states of the evanescent field present in the rarer medium in total internal reflection of incident monochromatic p-polarized light at a dielectric-dielectric planar interface are determined. Such conditions are satisfied if high-index (>3.2) transparent prism materials (e.g., GaP and Ge) are used at angles of incidence well above the critical angle but sufficiently below grazing incidence. Furthermore, elliptical polarization of incident light with nonzero p and s components can be tailored to cause circular polarization of the resultant tangential electric field in the plane of the interface or circular polarization of the …

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Poincaré Sphere Representation Of The Fixed-Polarizer Rotating-Retarder Optical System, R. M.A. Azzam Nov 2011

Poincaré Sphere Representation Of The Fixed-Polarizer Rotating-Retarder Optical System, R. M.A. Azzam

Electrical Engineering Faculty Publications

The trajectory of the polarization state of a monochromatic light beam after it passes through a fixed linear polarizer and a rotating linear retarder of arbitrary retardance Δ is determined on the Poincaré sphere. The three-dimensional figure-8 contour is shown to be the line of intersection of a right-circular cylinder with the sphere. The cylinder is parallel to the polar (s3) axis, touches the sphere at the equator (at the point that represents the linear polarization transmitted by the fixed polarizer), and has a radius r=sin2(Δ/2). Projections of the trajectory in the coordinate planes of the …

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Three-Dimensional Polarization States Of Monochromatic Light Fields, R. M.A. Azzam Oct 2011

Three-Dimensional Polarization States Of Monochromatic Light Fields, R. M.A. Azzam

Electrical Engineering Faculty Publications

The 3×1 generalized Jones vectors (GJVs) [ExEyEz]t (t indicates the transpose) that describe the linear, circular, and elliptical polarization states of an arbitrary three-dimensional (3-D) monochromatic light field are determined in terms of the geometrical parameters of the 3-D vibration of the time-harmonic electric field. In three dimensions, there are as many distinct linear polarization states as there are points on the surface of a hemisphere, and the number of distinct 3-D circular polarization states equals that of all two-dimensional (2-D) polarization states on the Poincaré sphere, of which only two are circular states. The subset of 3-D polarization …

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