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Electrical and Computer Engineering

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2018

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Articles 91 - 120 of 139

Full-Text Articles in Computer Engineering

Electron Effective Mass In In0.33ga0.67n Determined By Mid- Infrared Optical Hall Effect, Nerijus Armakavicius, Vallery Stanishev, Sean Knight, Mathias Schubert, Vanya Darakchieva Feb 2018

Electron Effective Mass In In0.33ga0.67n Determined By Mid- Infrared Optical Hall Effect, Nerijus Armakavicius, Vallery Stanishev, Sean Knight, Mathias Schubert, Vanya Darakchieva

Department of Electrical and Computer Engineering: Faculty Publications

Mid-infrared optical Hall effect measurements are used to determine the free charge carrier parameters of an unintentionally doped wurtzite-structure c-plane oriented In0.33Ga0.67N epitaxial layer. Room temperature electron effective mass parameters of m_ ¼ ð0:20560:013Þm0 andm_k ¼ ð0:20460:016Þm0 for polarization perpendicular and parallel to the c-axis, respectively,were determined. The free electron concentration was obtained as (1.760.2)_1019 cm-3. Within our uncertainty limits, we detect no anisotropy for the electron effective mass parameter and we estimate the upper limit of the possible effective mass anisotropy as 7%. We discuss the influence of conduction band nonparabolicity on …

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H.264 Video Decoder Implemented On Fpgas Using 3×3 And 2×2 Networks-On-Chip, Ian Barge, Cristinel Ababei Feb 2018

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 …

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Condensation And Subsequent Freezing Delays As A Result Of Using Femtosecond Laser Functionalized Surfaces, Chongji Huang, Ryan Bell, Alfred Tsubaki, Craig Zuhlke, Dennis Alexander Feb 2018

Condensation And Subsequent Freezing Delays As A Result Of Using Femtosecond Laser Functionalized Surfaces, Chongji Huang, Ryan Bell, Alfred Tsubaki, Craig Zuhlke, Dennis Alexander

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, the authors report on the use of femtosecond laser surface processing (FLSP) to enhance the anti-icing properties of a commonly used aircraft alloy, Al 7075-O Clad. By changing the surface morphology through FLSP and the surface chemistry through siloxane vapor deposition, the wettability of Al 7075-O Clad was altered. Tall mound and short mound FLSP functionalized surfaces were created through two sets of laser parameters. Condensation and the subsequent freezing of condensates on FLSP Al 7075-O Clad was studied. Both structure height and surface wettability were shown to play a role in the delay of freezing. Freezing …

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Internet Of Underground Things: Sensing And Communications On The Field For Precision Agriculture, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak Feb 2018

Internet Of Underground Things: Sensing And Communications On The Field For Precision Agriculture, Mehmet C. Vuran, Abdul Salam, Rigoberto Wong, Suat Irmak

CSE Conference and Workshop Papers

The projected increases in World population and need for food have recently motivated adoption of information technology solutions in crop fields within precision agriculture approaches. Internet of underground things (IOUT), which consists of sensors and communication devices, partly or completely buried underground for real-time soil sensing and monitoring, emerge from this need. This new paradigm facilitates seamless integration of underground sensors, machinery, and irrigation systems with the complex social network of growers, agronomists, crop consultants, and advisors. In this paper, state-of-the-art communication architectures are reviewed, and underlying sensing technology and communication mechanisms for IOUT are presented. Recent advances in the …

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Electronically Tuned Phase Transition In Germanium Telluride (Gete) Cells For Memory And Rf Switch Applications, Dushyant Tomer, Ronald A. Coutu Jr. Feb 2018

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 …

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Analytical Formulas For Mean Gain And Excess Noise Factor In Inas Avalanche Photodiodes, Erum Jamil, Majeed M. Hayat, Gordon A. Keeler Feb 2018

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 …

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A Fast And Robust Extrinsic Calibration For Rgb-D Camera Networks, Po-Chang Su, Ju Shen, Wanxin Xu, Sen-Ching S. Cheung, Ying Luo Jan 2018

A Fast And Robust Extrinsic Calibration For Rgb-D Camera Networks, Po-Chang Su, Ju Shen, Wanxin Xu, Sen-Ching S. Cheung, Ying Luo

Electrical and Computer Engineering Faculty Publications

From object tracking to 3D reconstruction, RGB-Depth (RGB-D) camera networks play an increasingly important role in many vision and graphics applications. Practical applications often use sparsely-placed cameras to maximize visibility, while using as few cameras as possible to minimize cost. In general, it is challenging to calibrate sparse camera networks due to the lack of shared scene features across different camera views. In this paper, we propose a novel algorithm that can accurately and rapidly calibrate the geometric relationships across an arbitrary number of RGB-D cameras on a network. Our work has a number of novel features. First, to cope …

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Lowering Legal Barriers To Rpki Adoption, Christopher S. Yoo, David A. Wishnick Jan 2018

Lowering Legal Barriers To Rpki Adoption, Christopher S. Yoo, David A. Wishnick

All Faculty Scholarship

Across the Internet, mistaken and malicious routing announcements impose significant costs on users and network operators. To make routing announcements more reliable and secure, Internet coordination bodies have encouraged network operators to adopt the Resource Public Key Infrastructure (“RPKI”) framework. Despite this encouragement, RPKI’s adoption rates are low, especially in North America.

This report presents the results of a year-long investigation into the hypothesis—widespread within the network operator community—that legal issues pose barriers to RPKI adoption and are one cause of the disparities between North America and other regions of the world. On the basis of interviews and analysis of …

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An Overview Of The Usage Of Default Passwords, Brandon Knierem, Xiaolu Zhang, Philip Levine, Frank Breitinger, Ibrahim Baggili Jan 2018

An Overview Of The Usage Of Default Passwords, Brandon Knierem, Xiaolu Zhang, Philip Levine, Frank Breitinger, Ibrahim Baggili

Electrical & Computer Engineering and Computer Science Faculty Publications

The recent Mirai botnet attack demonstrated the danger of using default passwords and showed it is still a major problem. In this study we investigated several common applications and their password policies. Specifically, we analyzed if these applications: (1) have default passwords or (2) allow the user to set a weak password (i.e., they do not properly enforce a password policy). Our study shows that default passwords are still a significant problem: 61% of applications inspected initially used a default or blank password. When changing the password, 58% allowed a blank password, 35% allowed a weak password of 1 character.

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Electron Effective Mass In Sn-Doped Monoclinic Single Crystal B-Gallium Oxide Determined By Mid-Infrared Optical Hall Effect, Sean Knight, Alyssa Mock, Rafal Korlacki, Vanya Darakchieva, Bo Monemar, Yoshinao Kumagai, Ken Goto, Masataka Higashiwaki, Mathias Schubert Jan 2018

Electron Effective Mass In Sn-Doped Monoclinic Single Crystal B-Gallium Oxide Determined By Mid-Infrared Optical Hall Effect, Sean Knight, Alyssa Mock, Rafal Korlacki, Vanya Darakchieva, Bo Monemar, Yoshinao Kumagai, Ken Goto, Masataka Higashiwaki, Mathias Schubert

Department of Electrical and Computer Engineering: Faculty Publications

The isotropic average conduction band minimum electron effective mass in Sn-doped monoclinic single crystal B-Ga2O3 is experimentally determined by the mid-infrared optical Hall effect to be (0.28460.013)m0 combining investigations on (010) and (_201) surface cuts. This result falls within the broad range of values predicted by theoretical calculations for undoped B-Ga2O3. The result is also comparable to recent density functional calculations using the Gaussian-attenuation- Perdew-Burke-Ernzerhof hybrid density functional, which predict an average effective mass of 0.267m0. Within our uncertainty limits, we detect no anisotropy for the electron effective mass, which …

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Uneven-Layered Coding Metamaterial Tile For Ultrawideband Rcs Reduction And Diffuse Scattering, Jianxun Su, Huan He, Zengrui Li, Yaoqing Lamar Yang, Hongcheng Yin, Junhong Wang Jan 2018

Uneven-Layered Coding Metamaterial Tile For Ultrawideband Rcs Reduction And Diffuse Scattering, Jianxun Su, Huan He, Zengrui Li, Yaoqing Lamar Yang, Hongcheng Yin, Junhong Wang

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, a novel uneven-layered coding metamaterial tile is proposed for ultra-wideband radar cross section (RCS) reduction and diffuse scattering. The metamaterial tile is composed of two kinds of square ring unit cells with different layer thickness. The reflection phase difference of 180° (±37°) between two unit cells covers an ultra-wide frequency range. Due to the phase cancellation between two unit cells, the metamaterial tile has the scattering pattern of four strong lobes deviating from normal direction. The metamaterial tile and its 90-degree rotation can be encoded as the ‘0’ and ‘1’ elements to cover an object, and diffuse …

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Electrons Dynamics Control By Shaping Femtosecond Laser Pulses In Micro/Nanofabrication: Modeling, Method, Measurement And Application, Lan Jiang, An-Dong Wang, Bo Li, Tian-Hong Cui, Yong-Feng Lu Jan 2018

Electrons Dynamics Control By Shaping Femtosecond Laser Pulses In Micro/Nanofabrication: Modeling, Method, Measurement And Application, Lan Jiang, An-Dong Wang, Bo Li, Tian-Hong Cui, Yong-Feng Lu

Department of Electrical and Computer Engineering: Faculty Publications

During femtosecond laser fabrication, photons are mainly absorbed by electrons, and the subsequent energy transfer from electrons to ions is of picosecond order. Hence, lattice motion is negligible within the femtosecond pulse duration, whereas femtosecond photon-electron interactions dominate the entire fabrication process. Therefore, femtosecond laser fabrication must be improved by controlling localized transient electron dynamics, which poses a challenge for measuring and controlling at the electron level during fabrication processes. Pump-probe spectroscopy presents a viable solution, which can be used to observe electron dynamics during a chemical reaction. In fact, femtosecond pulse durations are shorter than many physical/chemical characteristic times, …

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Ultraviolet Laser Photolysis Of Hydrocarbons For Nondiamond Carbon Suppression In Chemical Vapor Deposition Of Diamond Films, Li-Sha Fan, Loic Constantin, Da-Wei Li, Lei Liu, Kamran Keramatnejad, Clio Azina, Xi Huang, Hossein Rabiee Golgir, Yao Lu, Zahra Ahmadi, Fei Wang, Jeffrey E. Shield, Bai Cui, Jean-Francois Silvain, Yong-Feng Lu Jan 2018

Ultraviolet Laser Photolysis Of Hydrocarbons For Nondiamond Carbon Suppression In Chemical Vapor Deposition Of Diamond Films, Li-Sha Fan, Loic Constantin, Da-Wei Li, Lei Liu, Kamran Keramatnejad, Clio Azina, Xi Huang, Hossein Rabiee Golgir, Yao Lu, Zahra Ahmadi, Fei Wang, Jeffrey E. Shield, Bai Cui, Jean-Francois Silvain, Yong-Feng Lu

Department of Electrical and Computer Engineering: Faculty Publications

In this work, we demonstrate that ultraviolet (UV) laser photolysis of hydrocarbon species alters the flame chemistry such that it promotes the diamond growth rate and film quality. Optical emission spectroscopy and laser-induced fluorescence demonstrate that direct UV laser irradiation of a diamond-forming combustion flame produces a large amount of reactive species that play critical roles in diamond growth, thereby leading to enhanced diamond growth. The diamond growth rate is more than doubled, and diamond quality is improved by 4.2%. Investigation of the diamond nucleation process suggests that the diamond nucleation time is significantly shortened and nondiamond carbon accumulation is …

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Ears-Dm: Efficient Auto Correction Retrieval Scheme For Data Management In Edge Computing, Kai Fan, Jie Yin, Kuan Zhang, Hui Li, Yintang Wang Jan 2018

Ears-Dm: Efficient Auto Correction Retrieval Scheme For Data Management In Edge Computing, Kai Fan, Jie Yin, Kuan Zhang, Hui Li, Yintang Wang

Department of Electrical and Computer Engineering: Faculty Publications

Edge computing is an extension of cloud computing that enables messages to be acquired and processed at low cost. Many terminal devices are being deployed in the edge network to sense and deal with the massive data. By migrating part of the computing tasks from the original cloud computing model to the edge device, the message is running on computing resources close to the data source. The edge computing model can effectively reduce the pressure on the cloud computing center and lower the network bandwidth consumption. However, the security and privacy issues in edge computing are worth noting. In this …

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Optimal Computational Power Allocation In Multi-Access Mobile Edge Computing For Blockchain, Yuan Wu, Xiangxu Chen, Jiajun Shi, Kejie Ni, Liping Qian, Liang Huang, Kuan Zhang Jan 2018

Optimal Computational Power Allocation In Multi-Access Mobile Edge Computing For Blockchain, Yuan Wu, Xiangxu Chen, Jiajun Shi, Kejie Ni, Liping Qian, Liang Huang, Kuan Zhang

Department of Electrical and Computer Engineering: Faculty Publications

Blockchain has emerged as a decentralized and trustable ledger for recording and storing digital transactions. The mining process of Blockchain, however, incurs a heavy computational workload for miners to solve the proof-of-work puzzle (i.e., a series of the hashing computation), which is prohibitive from the perspective of the mobile terminals (MTs). The advanced multi-access mobile edge computing (MEC), which enables the MTs to offload part of the computational workloads (for solving the proof-of-work) to the nearby edge-servers (ESs), provides a promising approach to address this issue. By offloading the computational workloads via multi-access MEC, the MTs can effectively increase their …

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Structure-Mediated Excitation Of Air Plasma And Silicon Plasma Expansion In Femtosecond Laser Pulses Ablation, Qingsong Wang, Lan Jiang, Jingya Sun, Changji Pan, Weina Han, Guoyan Wang, Feifei Wang, Kaihu Zhang, Ming Li, Yongfeng Lu Jan 2018

Structure-Mediated Excitation Of Air Plasma And Silicon Plasma Expansion In Femtosecond Laser Pulses Ablation, Qingsong Wang, Lan Jiang, Jingya Sun, Changji Pan, Weina Han, Guoyan Wang, Feifei Wang, Kaihu Zhang, Ming Li, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Femtosecond laser-induced surface structures upon multiple pulses irradiation are strongly correlated with the pulse number,which in turn significantly affects successive laser-material interactions. By recording the dynamics of femtosecond laser ablation of silicon using time-resolved shadowgraphy, here we present direct visualization of the excitation of air plasma induced by the reflected laser during the second pulse irradiation.The interaction of the air plasma and silicon plasma is found to enhance the shockwave expansion induced by silicon ablation in the longitudinal direction, showing anisotropic expansion dynamics in different directions. We further demonstrate the vanishing of air plasma as the pulse number increases because …

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Deformation Behavior Of Foam Laser Targets Fabricated By Two-Photon Polymerization, Ying Liu, John H. Campbell, Ori Stein, Lijia Jiang, Jared Hund, Yongfeng Lu Jan 2018

Deformation Behavior Of Foam Laser Targets Fabricated By Two-Photon Polymerization, Ying Liu, John H. Campbell, Ori Stein, Lijia Jiang, Jared Hund, Yongfeng Lu

Department of Electrical and Computer Engineering: Faculty Publications

Two-photon polymerization (2PP), which is a three-dimensional micro/nano-scale additive manufacturing process, is used to fabricate component for small custom experimental packages (“targets”) to support laser-driven, high-energy-density physics research. Of particular interest is the use of 2PP to deterministically print millimeter-scale, low-density, and low atomic number (CHO) polymer matrices (“foams”). Deformation during development and drying of the foam structures remains a challenge when using certain commercial acrylic photo-resins. Acrylic resins were chosen in order to meet the low atomic number requirement for the foam; that requirement precludes the use of low-shrinkage organic/inorganic hybrid resins. Here, we compare the use of acrylic …

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Optimal Computational Power Allocation In Multi-Access Mobile Edge Computing For Blockchain, Yuan Wu, Xiangxu Chen, Jiajun Shi, Kejie Ni, Liping Qian, Liang Huang, Kuan Zhang Jan 2018

Optimal Computational Power Allocation In Multi-Access Mobile Edge Computing For Blockchain, Yuan Wu, Xiangxu Chen, Jiajun Shi, Kejie Ni, Liping Qian, Liang Huang, Kuan Zhang

Department of Electrical and Computer Engineering: Faculty Publications

Blockchain has emerged as a decentralized and trustable ledger for recording and storing digital transactions. The mining process of Blockchain, however, incurs a heavy computational workload for miners to solve the proof-of-work puzzle (i.e., a series of the hashing computation), which is prohibitive from the perspective of the mobile terminals (MTs). The advanced multi-access mobile edge computing (MEC), which enables the MTs to offload part of the computational workloads (for solving the proof-of-work) to the nearby edge-servers (ESs), provides a promising approach to address this issue. By offloading the computational workloads via multi-access MEC, the MTs can effectively increase their …

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Effect Of Weld Nugget Size On Failure Mode And Mechanical Properties Of Microscale Resistance Spot Welds On Ti–1al–1mn Ultrathin Foils, Feng Chen, Shiding Sun, Zhenwu Ma, G Q. Tong, Xiang Huang Jan 2018

Effect Of Weld Nugget Size On Failure Mode And Mechanical Properties Of Microscale Resistance Spot Welds On Ti–1al–1mn Ultrathin Foils, Feng Chen, Shiding Sun, Zhenwu Ma, G Q. Tong, Xiang Huang

Department of Electrical and Computer Engineering: Faculty Publications

We use tensile–shear tests to investigate the failure modes of Ti–1Al–1Mn microscale resistance spot welds and to determine how the failure mode affects the microstructure, microhardness profile, and mechanical performance. Two different failure modes were revealed: interfacial failure mode and pullout failure mode. The welds that fail by pullout failure mode have much better mechanical properties than those that fail by interfacial failure mode. The results show that weld nugget size is also a principal factor that determines the failure mode of microscale resistance spot welds. A minimum weld nugget size exists above which all specimens fail by pullout failure …

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Bias-Dependent Scanning Tunneling Microscopy Signature Of Bridging-Oxygen Vacancies On Rutile Tio2(110), Willie B. Maddox, Danda P. Acharya, G. Jeremy Leong, Peter Sutter, Cristian V. Ciobanu Jan 2018

Bias-Dependent Scanning Tunneling Microscopy Signature Of Bridging-Oxygen Vacancies On Rutile Tio2(110), Willie B. Maddox, Danda P. Acharya, G. Jeremy Leong, Peter Sutter, Cristian V. Ciobanu

Department of Electrical and Computer Engineering: Faculty Publications

The rutile TiO2(110) surface has long-served as a wellcharacterized, prototypical transition-metal oxide surface used in heterogeneous catalysis and photocatalytic water splitting. Naturally occurring defects on this surface, called bridging-oxygen (BO) vacancies, are important as they determine the overall reactivity of the surface. Herein, we report a bias-dependent, scanning tunneling microscopy (STM) signature of the BO vacancies on TiO2(110): for sample bias voltages past a threshold of +3 V, the bright vacancies are flanked on either side (along the oxygen row) by two dark spots approximately shaped like half-moons. The BO vacancies have a bright aspect below …

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Experimental Analyses On Multiscale Structural And Mechanical Properties Of Ε-Si/Gesi/C-Si Materials, Wei Qiu, Lu-Lu Ma, Hong-Tao Wang, Ren-Rong Liang, Yu-Cheng Zhao, Yun-Shen Zhou Jan 2018

Experimental Analyses On Multiscale Structural And Mechanical Properties Of Ε-Si/Gesi/C-Si Materials, Wei Qiu, Lu-Lu Ma, Hong-Tao Wang, Ren-Rong Liang, Yu-Cheng Zhao, Yun-Shen Zhou

Department of Electrical and Computer Engineering: Faculty Publications

Strained silicon (ε-Si) is a promising material that could extend Moore’s law by enhancing electron mobility. A ε-Si material is usually composed of multiscale, multilayer heterostructures, where the strained-silicon film or strap is tens-of-nanometers thick, and its buffer layers are of the micrometer scale. The structural properties determine the electrical performance and reliability of ε-Si-based devices. Inhomogeneous residual stress is induced during the preparation, which induces ε-Si structure failure. In this work, biaxial strained-silicon films that contain graded and relaxed germanium-silicon buffer layers were prepared on monocrystalline silicon wafers through reduced-pressure chemical-vapor epitaxy. The layer components and thicknesses were measured …

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Adaptive Transmission Range Based Topology Control Scheme For Fast And Reliable Data Collection, Haojun Teng, Kuan Zhang, Mianxiong Dong, Kaoru Ota, Anfeng Liu, Ming Zhao, Tian Wang Jan 2018

Adaptive Transmission Range Based Topology Control Scheme For Fast And Reliable Data Collection, Haojun Teng, Kuan Zhang, Mianxiong Dong, Kaoru Ota, Anfeng Liu, Ming Zhao, Tian Wang

Department of Electrical and Computer Engineering: Faculty Publications

An Adaptive Transmission Range Based Topology Control (ATRTC) scheme is proposed to reduce delay and improve reliability for data collection in delay and loss sensitive wireless sensor network. The core idea of the ATRTC scheme is to extend the transmission range to speed up data collection and improve the reliability of data collection.The main innovations of our work are as follows: (1) an adaptive transmission range adjustment method is proposed to improve data collection reliability and reduce data collection delay. The expansion of the transmission range will allow the data packet to be received by more receivers, thus improving the …

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Metasurface Base On Uneven Layered Fractal Elements For Ultra-Wideband Rcs Reduction, Jianxun Su, Yueyang Cui, Zengrui Li, Yaoqing (Lamar) Yang, Yongxing Che, Hongcheng Yin Jan 2018

Metasurface Base On Uneven Layered Fractal Elements For Ultra-Wideband Rcs Reduction, Jianxun Su, Yueyang Cui, Zengrui Li, Yaoqing (Lamar) Yang, Yongxing Che, Hongcheng Yin

Department of Electrical and Computer Engineering: Faculty Publications

A novel metasurface based on uneven layered fractal elements is designed and fabricated for ultra-wideband radar cross section (RCS) reduction in this paper. The proposed metasurface consists of two fractal subwavelength elements with different layer thickness. The reflection phase difference of 180◦ (±37◦) between two unit cells covers an ultra-wide frequency range. Ultra-wideband RCS reduction results from the phase cancellation between two local waves produced by these two unit cells. The diffuse scattering of electromagnetic (EM) waves is caused by the randomized phase distribution, leading to a low monostatic and bistatic RCS simultaneously. This metasurface can achieve …

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Information Theory And Cognition: A Review, Khalid Sayood Jan 2018

Information Theory And Cognition: A Review, Khalid Sayood

Department of Electrical and Computer Engineering: Faculty Publications

We examine how information theory has been used to study cognition over the last seven decades. After an initial burst of activity in the 1950s, the backlash that followed stopped most work in this area. The last couple of decades has seen both a revival of interest, and a more firmly grounded, experimentally justified use of information theory. We can view cognition as the process of transforming perceptions into information—where we use information in the colloquial sense of the word. This last clarification is one of the problems we run into when trying to use information theoretic principles to understand …

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Integrated Vacuum-Ultraviolet, Mid And Near-Ultraviolet, Visible, Near, Mid And Far Infrared And Terahertz Optical Hall Effect (Ohe) Instrument, And Method Of Use, Tino Hofmann, Mathias M. Schubert, Stefan Schoeche, Philipp Kuehne, Craig M. Herzinger, John A. Woollam, Gregory K. Pribil, Thomas E. Tiwald, Sean R. Knight Jan 2018

Integrated Vacuum-Ultraviolet, Mid And Near-Ultraviolet, Visible, Near, Mid And Far Infrared And Terahertz Optical Hall Effect (Ohe) Instrument, And Method Of Use, Tino Hofmann, Mathias M. Schubert, Stefan Schoeche, Philipp Kuehne, Craig M. Herzinger, John A. Woollam, Gregory K. Pribil, Thomas E. Tiwald, Sean R. Knight

Department of Electrical and Computer Engineering: Faculty Publications

Optical Hall Effect (OHE) method for evaluating such as free charge carrier effective mass, concentration, mobility and free charge carrier type in a sample utilizing a permanent magnet at room temperature.

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Comparative Study On Various Dielectric Barriers And Their Effect On Breakdown Voltage, Elham Foruzan, Amir A. S. Akmal, Kaveh Niayesh, Jeremy Lin, Desh Deepak Sharma Jan 2018

Comparative Study On Various Dielectric Barriers And Their Effect On Breakdown Voltage, Elham Foruzan, Amir A. S. Akmal, Kaveh Niayesh, Jeremy Lin, Desh Deepak Sharma

Department of Electrical and Computer Engineering: Faculty Publications

Non-pressurised air is extensively used as basic insulation medium in high-voltage equipment. Unfortunately, an inherent property of air-insulated design is that the system tends to become physically large. On the other hand, the application of dielectric barriers can increase the breakdown voltage and therefore decrease the size of the equipment. In this study, the impact of dielectric barriers on breakdown voltage enhancement is investigated under both direct current (dc) and alternating current (ac) applied voltages. For this purpose, three kinds of dielectric barriers in two different high-voltage electrode structures are investigated. In the first structure, several experiments are carried out …

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Fiber - Optic Temperature And Flow Sensor System And Methods, Ming Han, Guigen Liu, Weilin Hou Jan 2018

Fiber - Optic Temperature And Flow Sensor System And Methods, Ming Han, Guigen Liu, Weilin Hou

Department of Electrical and Computer Engineering: Faculty Publications

A fiber optic sensor, a process for utilizing a fiber optic sensor, and a process for fabricating a fiber optic sensor are described, where a double-side-polished silicon pillar is attached to an optical fiber tip and forms a Fabry-Perot cavity. In an implementation, a fiber optic sensor in accordance with an exemplary embodiment includes an optical fiber configured to be coupled to a light source and a spectrometer; and a single silicon layer or multiple silicon layers disposed on an end face of the optical fiber, where each of the silicon layer(s) defines a Fabry-Perot interferometer, and where the sensor …

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Non-Vacuum Preparation Of Wse2 Thin Films Via The Selenization Of Hydrated Tungsten Oxide Prepared Using Chemical Solution Methods, Christopher L. Exstrom, Scott A. Darveau, Megan E. Falconer, Jessica R. Blum, Whitney M. Colling, Natale J. Ianno Jan 2018

Non-Vacuum Preparation Of Wse2 Thin Films Via The Selenization Of Hydrated Tungsten Oxide Prepared Using Chemical Solution Methods, Christopher L. Exstrom, Scott A. Darveau, Megan E. Falconer, Jessica R. Blum, Whitney M. Colling, Natale J. Ianno

Department of Electrical and Computer Engineering: Faculty Publications

It is known that tungsten oxide may be reacted with selenium sources to form WSe2 but literature reports include processing steps that involve high temperatures, reducing atmospheres, and/or oxidative pre-treatments of tungsten oxide. In this work, we report a non-vacuum process for the fabrication of compositionally high quality WSe2 thin films via the selenization of tungsten oxide under milder conditions. Tungsten source materials were various hydrated WO3 and WO2.9 compounds that were prepared using chemical solution techniques. Resulting films were selenized using a two-stage heating profile (250 °C for 15 minutes and 550 °C for 30 …

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Non-Vacuum Preparation Of Wse2 Thin Films Via The Selenization Of Hydrated Tungsten Oxide Prepared Using Chemical Solution Methods, Christopher L. Exstrom, Scott A. Darveau, Megan E. Flaconer, Jessica R. Blum, Whitney M. Colling, Natale J. Ianno Jan 2018

Non-Vacuum Preparation Of Wse2 Thin Films Via The Selenization Of Hydrated Tungsten Oxide Prepared Using Chemical Solution Methods, Christopher L. Exstrom, Scott A. Darveau, Megan E. Flaconer, Jessica R. Blum, Whitney M. Colling, Natale J. Ianno

Department of Electrical and Computer Engineering: Faculty Publications

It is known that tungsten oxide may be reacted with selenium sources to form WSe2 but literature reports include processing steps that involve high temperatures, reducing atmospheres, and/or oxidative pre-treatments of tungsten oxide. In this work, we report a non-vacuum process for the fabrication of compositionally high quality WSe2 thin films via the selenization of tungsten oxide under milder conditions. Tungsten source materials were various hydrated WO3 and WO2.9 compounds that were prepared using chemical solution techniques. Resulting films were selenized using a two-stage heating profile (250 oC for 15 minutes and 550 oC for 30 minutes) under a static …

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Method Ofobtaining Micrographs Of Transparent Or Semi-Transparent Specimens Using Anisotropic Contrast, Tino Hofmann, Mathias M. Schubert, Tadas Kasputis, Angela K. Pannier, Craig M. Herzinger, John A. Woollam Jan 2018

Method Ofobtaining Micrographs Of Transparent Or Semi-Transparent Specimens Using Anisotropic Contrast, Tino Hofmann, Mathias M. Schubert, Tadas Kasputis, Angela K. Pannier, Craig M. Herzinger, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

Anisotropic contrast methodology in combination with use of sample investigating polarized electromagnetic radiation to provide Jones or Mueller Matrix imaging data corresponding to areas on samples.

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