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Electrical and Computer Engineering Faculty Research & Creative Works

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Full-Text Articles in Engineering

Synaptic Plasticity Emulation By Natural Biomaterial Honey-Cnt-Based Memristors, Zoe Templin, Md Mehedi Hasan Tanim, Feng Zhao Dec 2023

Synaptic Plasticity Emulation By Natural Biomaterial Honey-Cnt-Based Memristors, Zoe Templin, Md Mehedi Hasan Tanim, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

Artificial synaptic devices made from natural biomaterials capable of emulating functions of biological synapses, such as synaptic plasticity and memory functions, are desirable for the construction of brain-inspired neuromorphic computing systems. The metal/dielectric/metal device structure is analogous to the pre-synapse/synaptic cleft/post-synapse structure of the biological neuron, while using natural biomaterials promotes ecologically friendly, sustainable, renewable, and low-cost electronic devices. In this work, artificial synaptic devices made from honey mixed with carbon nanotubes, honey-carbon nanotube (CNT) memristors, were investigated. The devices emulated spike-timing-dependent plasticity, with synaptic weight as high as 500%, and demonstrated a paired-pulse facilitation gain of 800%, which is …

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Microwave-Photonic Vernier Effect Enabled High-Sensitivity Fiber Bragg Grating Sensors For Point-Wise And Quasi-Distributed Sensing, Chen Zhu, Osamah Alsalman, Jie Huang Dec 2023

Microwave-Photonic Vernier Effect Enabled High-Sensitivity Fiber Bragg Grating Sensors For Point-Wise And Quasi-Distributed Sensing, Chen Zhu, Osamah Alsalman, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This paper reports a sensitivity-improved fiber Bragg grating (FBG) sensor system based on microwave-photonic interferometry and the Vernier effect. an incoherent microwave photonics system based on a broadband light source is employed to interrogate the FBG sensor using the wavelength-to-delay mapping technique combined with interferometry. Specifically, the sensing FBG together with a reference FBG is used to construct a microwave photonics Michelson interferometer (MI). Changes in the Bragg wavelength of the sensing FBG subject to external perturbations are encoded into the spectral shifts of the microwave interferogram of the MI. a virtual interferometer is then generated from the sensing MI …

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Space-Time-Frequency Characterization In Electromagnetic Near-Field Scanning: A Data-Driven Approach, Yanming Zhang, Lijun Jiang Dec 2023

Space-Time-Frequency Characterization In Electromagnetic Near-Field Scanning: A Data-Driven Approach, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Near-field scanning has become a widely used tool for diagnosing electromagnetic compatibility and electromagnetic interference issues. However, the transient signal of the device under test often contains multiple frequency bands and exhibits nonstationarity, which poses a challenge for near-field scanning analysis. To address this issue, this article presents a method for analyzing time-resolved near-field radiation based on multiresolution dynamic mode decomposition (MRDMD). The MRDMD approach recursively and hierarchically applies the traditional dynamic mode decomposition (DMD) method. The distribution of DMD eigenvalues determines the slow and fast modes in each level's decomposition, where the slow modes are preserved, and the fast …

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Graphene-Based Chemiresistor Sensors For Drinking Water Quality Monitoring, Mason Mcgarrity, Feng Zhao Dec 2023

Graphene-Based Chemiresistor Sensors For Drinking Water Quality Monitoring, Mason Mcgarrity, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

Monitoring the quality of drinking water is a crucial responsibility for all water infrastructure networks, as it guarantees access to clean water for the communities they serve. With water infrastructure deteriorating due to age and neglect, drinking water violations are on the rise in the US, underscoring the need for improved monitoring capabilities. Among the different sensor technologies, graphene-based Chemi resistors have emerged as a promising technology for water quality monitoring due to advantages such as simple design, sensitivity, and selectivity. This review paper provides an overview of recent advances in the development of graphene-based Chemi resistors for water quality …

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Data-Driven Scheme For Joint Estimation Of Direction-Of-Arrival And Frequency With Uniform Linear Array, Yanming Zhang, Lijun Jiang, Hsi Tseng Chou Dec 2023

Data-Driven Scheme For Joint Estimation Of Direction-Of-Arrival And Frequency With Uniform Linear Array, Yanming Zhang, Lijun Jiang, Hsi Tseng Chou

Electrical and Computer Engineering Faculty Research & Creative Works

This article presents a two-step dynamic mode decomposition (TSDMD) approach to estimate the direction of arrival (DOA) and frequency for multiple narrow-band sources with single uniform linear array (ULA). The proposed algorithm first decomposes the receiving spatial-temporal data into temporal dynamic modes and corresponding spatial spectrum that yields the DOA information. Then the decomposed temporal dynamic modes are analyzed via the augmented DMD to retrieve the frequency information. The estimated DOAs and frequencies are automatically paired without the extra computational cost with such a temporal-spectral correlated decomposition scheme. Also, the obtained spatial spectrum distribution implies the actual number of the …

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Electromagnetic-Thermal Co-Design Of Base Station Antennas With All-Metal Ebg Structures, Huan Huan Zhang, Jun Bo Chao, Yi Wei Wang, Ying Liu, Yun Xue Xu, Heming Yao, Lijun Jiang, Xiang Hua Li Dec 2023

Electromagnetic-Thermal Co-Design Of Base Station Antennas With All-Metal Ebg Structures, Huan Huan Zhang, Jun Bo Chao, Yi Wei Wang, Ying Liu, Yun Xue Xu, Heming Yao, Lijun Jiang, Xiang Hua Li

Electrical and Computer Engineering Faculty Research & Creative Works

In order to improve the heat dissipation capability of the 5G base station, the electromagnetic and thermal performances of a base station antenna array are co-designed by adopting all-metal electromagnetic bandgap (EBG) structures. The geometrical dimension of the EBG structure is determined through balancing the electromagnetic and thermal performances of the antenna array. The operating frequency band (voltage standing wave ratio (VSWR) < 1.5) of the proposed antenna array can cover 3.4-3.8 GHz. Its realized gains, isolation, cross-polarized discrimination ratio, and half-power beamwidth are satisfactory compared with other state-of-the-art base station antennas. Most importantly, more than 9 C temperature reduction can be observed when comparing the heat dissipation capability of the proposed antenna array with the reference antenna array.

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Modeling Hydration Kinetics Of Sustainable Cementitious Binders Using An Advanced Nucleation And Growth Approach, Taihao Han, Jie Huang, Gaurav Sant, Narayanan Neithalath, Ashutosh Goel, Aditya Kumar Nov 2023

Modeling Hydration Kinetics Of Sustainable Cementitious Binders Using An Advanced Nucleation And Growth Approach, Taihao Han, Jie Huang, Gaurav Sant, Narayanan Neithalath, Ashutosh Goel, Aditya Kumar

Electrical and Computer Engineering Faculty Research & Creative Works

Supplementary cementitious materials (SCMs) are utilized to partially substitute Portland cement (PC) in binders, reducing carbon-footprint and maintaining excellent performance. Nonetheless, predicting the hydration kinetics of [PC + SCM] binders is challenging for current analytical models due to the extensive diversity of chemical compositions and molecular structures present in both SCMs and PC. This study develops an advanced phase boundary nucleation and growth (pBNG) model to yield a priori predictions of hydration kinetics—i.e., time-resolved exothermic heat release profiles—of [PC + SCM] binders. The advanced pBNG model integrates artificial intelligence as an add-on, enabling it to accurately simulate hydration kinetics for …

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Boosting Snr Of Cascaded Fbgs In A Sapphire Fiber Through A Rapid Heat Treatment, Farhan Mumtaz, Hanok Tekle, Bohong Zhang, Jeffrey D. Smith, Ronald J. O'Malley, Rex E. Gerald, Jie Huang Nov 2023

Boosting Snr Of Cascaded Fbgs In A Sapphire Fiber Through A Rapid Heat Treatment, Farhan Mumtaz, Hanok Tekle, Bohong Zhang, Jeffrey D. Smith, Ronald J. O'Malley, Rex E. Gerald, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This Letter reports the performance of femtosecond (fs) laser-written distributed fiber Bragg gratings (FBGs) under high-temperature conditions up to 1600°C and explores the impact of rapid heat treatment on signal-to-noise ratio (SNR) enhancement. FBGs are essential for reliable optical sensing in extreme temperature environments. Comprehensive tests demonstrate the remarkable performance and resilience of FBGs at temperatures up to 1600°C, confirming their suitability for deployment in such conditions. The study also reveals significant fringe visibility improvements of up to ∼10 dB on a 1-m-long sapphire optical fiber through rapid heat treatment, representing a first-time achievement to the best of our knowledge. …

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Qc-Sane: Robust Control In Drl Using Quantile Critic With Spiking Actor And Normalized Ensemble, Surbhi Gupta, Gaurav Singal, Deepak Garg, Sarangapani Jagannathan Sep 2023

Qc-Sane: Robust Control In Drl Using Quantile Critic With Spiking Actor And Normalized Ensemble, Surbhi Gupta, Gaurav Singal, Deepak Garg, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Recently Introduced Deep Reinforcement Learning (DRL) Techniques in Discrete-Time Have Resulted in Significant Advances in Online Games, Robotics, and So On. Inspired from Recent Developments, We Have Proposed an Approach Referred to as Quantile Critic with Spiking Actor and Normalized Ensemble (QC-SANE) for Continuous Control Problems, Which Uses Quantile Loss to Train Critic and a Spiking Neural Network (NN) to Train an Ensemble of Actors. the NN Does an Internal Normalization using a Scaled Exponential Linear Unit (SELU) Activation Function and Ensures Robustness. the Empirical Study on Multijoint Dynamics with Contact (MuJoCo)-Based Environments Shows Improved Training and Test Results Than …

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Fs-Laser Fabricated Miniature Fabry–Perot Interferometer In A No-Core Fiber For High-Temperature Applications †, Chen Zhu, Osamah Alsalman, Jie Huang Sep 2023

Fs-Laser Fabricated Miniature Fabry–Perot Interferometer In A No-Core Fiber For High-Temperature Applications †, Chen Zhu, Osamah Alsalman, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Reports a Fiber In-Line Fabry–Perot Interferometer (FPI) Fabricated in a No-Core Fiber using the Direct Femtosecond Laser Writing Technique for High-Temperature Sensing Applications. Two In-Line Reflectors Are Directly Inscribed in a No-Core Fiber to Construct a Low-Finesse FPI. Fringe Visibility Greater Than 10 DB is Obtained from the Reflection Spectra of the Fabricated No-Core Fiber FPIs. Temperature Responses of a Prototype No-Core Fiber FPI Are Characterized Up to 1000 °C. the Proposed Configuration is Compact and Easy to Fabricate, Making It Attractive for Sensing Applications in High-Temperature Harsh Environments.

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Multifunctional Organic Monolayer-Based Coatings For Implantable Biosensors And Bioelectronic Devices: Review And Perspectives, Taral Patel, Jie Huang, Katarzyna Krukiewicz Sep 2023

Multifunctional Organic Monolayer-Based Coatings For Implantable Biosensors And Bioelectronic Devices: Review And Perspectives, Taral Patel, Jie Huang, Katarzyna Krukiewicz

Electrical and Computer Engineering Faculty Research & Creative Works

The Emerging Field of Biosensors and Bioelectronics Seeks to Exploit Biology in Combination with the Recent Advances in Engineering. Even Though Biomedical Implants Can Significantly Improve Quality of Life, Problems Following the Process of Implantation Are Still an Issue. in This Review, We Point Out Organic Monolayer-Based Coatings as a Potential Solution to the Major Limitations of Implantable Biomaterials, Including Limited Biocompatibility, the Risk of Biofouling, Bacterial Colonization, and Stability under in Vivo Conditions. at First, Selected Current and Perspective Biomaterials Are Discussed, with the Focus on their Use as Implantable Biosensors and Biomedical Electrodes. Surface Modification Strategies for Implantable …

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In Situ Monitoring Of The Hydration Of Calcium Silicate Minerals In Cement With A Remote Fiber-Optic Raman Probe, Bohong Zhang, Wenyu Liao, Hongyan Ma, Jie Huang Sep 2023

In Situ Monitoring Of The Hydration Of Calcium Silicate Minerals In Cement With A Remote Fiber-Optic Raman Probe, Bohong Zhang, Wenyu Liao, Hongyan Ma, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This study utilized a novel in situ fiber-optic Raman probe to continuously monitor the hydration progress of tricalcium silicate (C3S) and dicalcium silicate (C2S) without the need for sampling, from early hydration stage to later stages, and from fresh to hardened states of paste samples. by virtue of the remarkable ability of this technique in characterizing either dry or wet and crystalline or amorphous samples, the hydration processes of C3S and C2S pastes with different water-to-solid (w/s) ratios could be monitored from the start of the hydration reaction. the main hydration products, calcium silicate hydrate (C–S–H) and portlandite/calcium hydroxide (CH), …

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Large-Scale Cascading Of First-Order Fbg Array In A Highly Multimode Coreless Fiber Using Femtosecond Laser For Distributed Thermal Sensing, Farhan Mumtaz, Bohong Zhang, Ronald J. O'Malley, Jie Huang Aug 2023

Large-Scale Cascading Of First-Order Fbg Array In A Highly Multimode Coreless Fiber Using Femtosecond Laser For Distributed Thermal Sensing, Farhan Mumtaz, Bohong Zhang, Ronald J. O'Malley, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This research focuses on the performance analysis and characterization of a fiber Bragg gratings (FBGs) array, consisting of 10 first order FBGs inscribed by a femtosecond (FS) laser in a highly multimode coreless fiber. The study evaluates the FBG array's ability to function as a distributed thermal sensing (DTS) platform, with the coreless fiber chosen as the sensing element due to its immunity to dopant migration at high temperatures. The design of a large cascaded first-order FBG array effectively eliminates unwanted harmonic peaks across a wide spectrum range. In contrast, higher-order FBGs introduce limitations due to the overlapping of Bragg …

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A Direct Data Approach To Joint 2-D Doa And Frequency Estimation With L-Shaped Array, Yanming Zhang, Lijun Jiang Aug 2023

A Direct Data Approach To Joint 2-D Doa And Frequency Estimation With L-Shaped Array, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This article presents a joint two-dimensional dynamic mode decomposition (JTDDMD) approach to estimate the azimuth angle, elevation angle, and frequency for multiple narrowband sources using the L-shaped array. According to the placement position of different coordinate axes of the receiving antenna in the array, i.e., x- or z-axis, the received signal is divided into two datasets. Two-dimensional dynamic mode decomposition (TDDMD), the sub algorithm of JTDDMD, is used twice to deal with these two datasets separately. Through the analysis of the x-axis subarray received signal using TDDMD, the electrical angle in the x-direction and frequency are obtained with automatic pairing. …

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Localization And Identification Of Emi Sources In Shielding Enclosures Based On A Two-Step Source Reconstruction Method, Zi An Wang, Jun Fa Mao, Li (Lijun) Jun Jiang, Ping Li Aug 2023

Localization And Identification Of Emi Sources In Shielding Enclosures Based On A Two-Step Source Reconstruction Method, Zi An Wang, Jun Fa Mao, Li (Lijun) Jun Jiang, Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

Localization and identification of unknown electromagnetic interference (EMI) sources in shielding enclosures is a great challenge due to the complex electromagnetic environment. In this work, a two-step source reconstruction method is proposed to address this issue. The actual EMI sources are initially modeled by equally distributed equivalent electric dipoles in the shielding enclosure. Effects of surrounding environments are rigorously incorporated using the numerical Green's function which bridges between the equivalent dipoles and planar scanned tangential magnetic near-field. Next, the initial equivalent sources are downsized via evaluating the contribution of each equivalent dipole. The parameters of remaining equivalent dipoles are updated …

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Silicon Carbide-Based Dna Sensing Technologies, Abdulla Al Mamun, Mason Mcgarrity, Jong Hoon Kim, Feng Zhao Aug 2023

Silicon Carbide-Based Dna Sensing Technologies, Abdulla Al Mamun, Mason Mcgarrity, Jong Hoon Kim, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

DNA sensing is critical in various applications such as the early diagnosis of diseases and the investigation of forensic evidence, food processing, agriculture, environmental protection, etc. As a wide-bandgap semiconductor with excellent chemical, physical, electrical, and biocompatible properties, silicon carbide (SiC) is a promising material for DNA sensors. In recent years, a variety of SiC-based DNA-sensing technologies have been reported, such as nanoparticles and quantum dots, nanowires, nanopillars, and nanowire-based field-effect-transistors, etc. This article aims to provide a review of SiC-based DNA sensing technologies, their functions, and testing results.

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A Natural Organic Artificial Synaptic Device Made From A Honey And Carbon Nanotube Admixture For Neuromorphic Computing, Md Mehedi Hasan Tanim, Zoe Templin, Kaleb Hood, Jun Jiao, Feng Zhao Jul 2023

A Natural Organic Artificial Synaptic Device Made From A Honey And Carbon Nanotube Admixture For Neuromorphic Computing, Md Mehedi Hasan Tanim, Zoe Templin, Kaleb Hood, Jun Jiao, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

Artificial synaptic devices are the essential hardware component in emerging neuromorphic computing systems by mimicking biological synapse and brain functions. When made from natural organic materials such as protein and carbohydrate, they have potential to improve sustainability and reduce electronic waste by enabling environmentally friendly disposal. In this paper, a new natural organic memristor based artificial synaptic device is reported with the memristive film processed by a honey and carbon nanotube (CNT) admixture, that is, honey-CNT memristor. Optical microscopy, scanning electron microscopy, and micro-Raman spectroscopy are employed to analyze the morphology and chemical structure of the honey-CNT film. The device …

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A Non-Line-Of-Sight Mitigation Method For Indoor Ultra-Wideband Localization With Multiple Walls, Mengyao Dong, Yihong Qi, Xianbin Wang, Yiming Liu Jul 2023

A Non-Line-Of-Sight Mitigation Method For Indoor Ultra-Wideband Localization With Multiple Walls, Mengyao Dong, Yihong Qi, Xianbin Wang, Yiming Liu

Electrical and Computer Engineering Faculty Research & Creative Works

Ultra-wideband (UWB) ranging techniques can provide accurate distance measurement under line-of-sight (LOS) conditions. However, various walls and obstacles in indoor non-LOS (NLOS) environments, which obstruct the direct propagation of UWB signals, can generate significant ranging errors. Due to the complex through-wall UWB signal propagation, most conventional studies simplify the ranging error model by assuming that the incidence angle is zero or the relative permittivity's for different walls are the same to improve the through-wall UWB localization performance. Considering walls are different in realistic settings, this article presents a through-multiple-wall NLOS mitigation method for UWB indoor positioning. First, spatial geometric equilibrium …

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Detection Of Critical Cancer Cells In Human Organs Using Dual Demodulation Photonic Crystal Fiber: Numerical Study, Farhan Mumtaz Jul 2023

Detection Of Critical Cancer Cells In Human Organs Using Dual Demodulation Photonic Crystal Fiber: Numerical Study, Farhan Mumtaz

Electrical and Computer Engineering Faculty Research & Creative Works

This study reports a novel approach for early detection of malignant cancer cells in human organs using a birefringent photonic crystal fiber (PCF)-based optical sensor with dual demodulation. The PCF injects light into the middle hole, enhancing the radiated evanescent field. Analytes injected through the core cause a wavelength shift, measured by peak or dip shift. The proposed sensor has an optimal sensitivity of −7,940 nm/RIU, −8,265 nm/RIU, −9,747 nm/RIU, −9,006 nm/RIU, and −8,994 nm/RIU by peak shift and −8,745 nm/RIU, −10,728 nm/RIU, −8,721 nm/RIU, −10,113 nm/RIU, and −11,150 nm/RIU by dip shift for CRT-(Cervical tissue), BLD-(Blood), ADG-(Adrenal gland), BRT-(Breast) …

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Nonmonotonic Effect Of Chemical Heterogeneity On Interfacial Crack Growth At High-Angle Grain Boundaries In Fe-Ni-Cr Alloys, Yuchu Wang, Bita Ghaffari, Christopher Taylor, Simon Lekakh, Carlos Engler-Pinto, Larry Godlewski, Yang Huo, Mei Li, Yue Fan Jul 2023

Nonmonotonic Effect Of Chemical Heterogeneity On Interfacial Crack Growth At High-Angle Grain Boundaries In Fe-Ni-Cr Alloys, Yuchu Wang, Bita Ghaffari, Christopher Taylor, Simon Lekakh, Carlos Engler-Pinto, Larry Godlewski, Yang Huo, Mei Li, Yue Fan

Electrical and Computer Engineering Faculty Research & Creative Works

An intermittent pattern is observed in the modeling of interfacial cyclic-loading crack growth at high-angle grain boundaries in ternary Fe-Ni-Cr alloys. Different from conventional wisdom of stress-intensity factor, the abrupt crack advances are found driven by extreme value statistics - namely, the aggregation of atoms with most compressive residual stresses. In addition, inherently non-affine atomic stress fluctuations are discovered, and the fluctuations peak at intermediate level of chemical heterogeneity, causing the fastest crack growth. Implications of such nonmonotonic mechanism in regard to the origin of intermediate-temperature embrittlement phenomena are also discussed.

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Cu2o Heterojunction Solar Cell With Photovoltaic Properties Enhanced By A Ti Buffer Layer, Binghao Wang, Zhiqiang Chen, Feng Zhao Jul 2023

Cu2o Heterojunction Solar Cell With Photovoltaic Properties Enhanced By A Ti Buffer Layer, Binghao Wang, Zhiqiang Chen, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

In this study, semiconductor oxide cuprite (Cu2O) and indium tin oxide (ITO) heterojunction solar cells with and without a 10 nm thick titanium (Ti) thin film as the buffer layer were fabricated and characterized for comparison. The Cu2O film was formed by low-cost electrodeposition, and Ti and ITO layers were deposited on a glass substrate by sputtering. The interfacial microstructures, surface topology, and electrical and photovoltaic properties of both solar cells were investigated. The test results showed that the Ti buffer layer changed the surface morphology, resistivity, and contact potential of the electrodeposited Cu2O …

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Fusion Of Microgrid Control With Model-Free Reinforcement Learning: Review And Vision, Buxin She, Fangxing Li, Hantao Cui, Jingqiu Zhang, Rui Bo Jul 2023

Fusion Of Microgrid Control With Model-Free Reinforcement Learning: Review And Vision, Buxin She, Fangxing Li, Hantao Cui, Jingqiu Zhang, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

Challenges and opportunities coexist in microgrids as a result of emerging large-scale distributed energy resources (DERs) and advanced control techniques. In this paper, a comprehensive review of microgrid control is presented with its fusion of model-free reinforcement learning (MFRL). A high-level research map of microgrid control is developed from six distinct perspectives, followed by bottom-level modularized control blocks illustrating the configurations of grid-following (GFL) and grid-forming (GFM) inverters. Then, mainstream MFRL algorithms are introduced with an explanation of how MFRL can be integrated into the existing control framework. Next, the application guideline of MFRL is summarized with a discussion of …

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Hydrogen Gas Sensor Based On Seven-Core Fiber Interference And Pt-Wo3 Film, You Wang, Farhan Mumtaz, Yutang Dai Jun 2023

Hydrogen Gas Sensor Based On Seven-Core Fiber Interference And Pt-Wo3 Film, You Wang, Farhan Mumtaz, Yutang Dai

Electrical and Computer Engineering Faculty Research & Creative Works

Tungsten oxide (WO3) typically owns the characteristics of electrochemical, photo-chromic, and gas-chromic. The seven-core fiber (SCF) generates a strong interference signal that comprises super-modes. The thermo-optic and thermo-expansion characteristics of SCF were utilized with an aid of Pt-WO3 film that makes the sensor highly sensitive to the H2 gas environment. The sensor with spiral micro grooves by femtosecond-laser ablation considerably enhanced the H2 sensitivity from 3.28 nm% to 4.0 nm%, and obtained a response and recovery time < 90 s.

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Time-Domain Shielding Effectiveness Analysis Based On Dgtd Method Accelerated By Local Time-Stepping And Parallel Techniques, Zheng Lang Jia, Huan Huan Zhang, Da Zhi Ding, Lei Zhao, Qiang Ren, Li (Lijun) Jun Jiang Jun 2023

Time-Domain Shielding Effectiveness Analysis Based On Dgtd Method Accelerated By Local Time-Stepping And Parallel Techniques, Zheng Lang Jia, Huan Huan Zhang, Da Zhi Ding, Lei Zhao, Qiang Ren, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The discontinuous Galerkin time-domain (DGTD) method accelerated by local time-stepping (LTS) and parallel techniques is employed to analyze the time-domain shielding effectiveness (TDSE) of metallic enclosures. The detailed formulations and implementation procedures of the DGTD method and LTS and parallel techniques are introduced. Numerical results validate the correctness of the proposed method. Moreover, the influence of various design parameters of the metallic enclosure, including aperture dimensions, wall thickness, spacing of aperture arrays, etc., on the TDSE are analyzed by the proposed method. Some rules are given for the design of the enclosure with rectangular apertures from the perspective of TDSE. …

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Hybrid Model To Evaluate The Frequency-Dependent Leakage Inductance Of Partially-Filled Transformers, Angshuman Sharma, Jonathan W. Kimball Jun 2023

Hybrid Model To Evaluate The Frequency-Dependent Leakage Inductance Of Partially-Filled Transformers, Angshuman Sharma, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

The leakage inductance of a transformer designed for a power electronic converter can drop significantly as the switching frequency is increased due to skin and proximity effects. Although the magnetic image method-Based double-2-D model can predict the low-frequency leakage inductance of a partially filled transformer with sufficient accuracy, it is inherently a frequency-independent model. While Dowell's 1-D model uses frequency-dependent relations to account for both skin and proximity effects, its accuracy is severely affected by the assumed winding geometry. in this paper, a semi-analytical hybrid model is proposed that uses superposition to combine a modified Dowell's model with the double-2-D …

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Optimal Offering Strategy Of Genco With Joint Participation In Ftr Auction And Day-Ahead Market Considering Virtual Bidding, Hossein Mehdipourpicha, Rui Bo, Siyuan Wang May 2023

Optimal Offering Strategy Of Genco With Joint Participation In Ftr Auction And Day-Ahead Market Considering Virtual Bidding, Hossein Mehdipourpicha, Rui Bo, Siyuan Wang

Electrical and Computer Engineering Faculty Research & Creative Works

Nodal price separations in Day-Ahead (DA) market caused by transmission congestion create congestion charges/surplus that are reallocated to the market participants through the financial transmission right (FTR) auction. From a market participant's viewpoint, these two markets are interrelated because the revenue of market participant in FTR auction is determined based on the day-ahead locational marginal prices. Furthermore, virtual transactions which are designed to improve price convergence between the day-ahead and real-time markets can directly impact day-ahead prices. This impact through virtual transactions may be utilized by a market participant to increase its FTR value and improve its overall strategy in …

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A Machine Learning Specklegram Wavemeter (Maswave) Based On A Short Section Of Multimode Fiber As The Dispersive Element, Ogbole C. Inalegwu, Rex E. Gerald, Jie Huang May 2023

A Machine Learning Specklegram Wavemeter (Maswave) Based On A Short Section Of Multimode Fiber As The Dispersive Element, Ogbole C. Inalegwu, Rex E. Gerald, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Wavemeters are very important for precise and accurate measurements of both pulses and continuous-wave optical sources. Conventional wavemeters employ gratings, prisms, and other wavelength-sensitive devices in their design. Here, we report a simple and low-cost wavemeter based on a section of multimode fiber (MMF). The concept is to correlate the multimodal interference pattern (i.e., speckle patterns or specklegrams) at the end face of an MMF with the wavelength of the input light source. Through a series of experiments, specklegrams from the end face of an MMF as captured by a CCD camera (acting as a low-cost interrogation unit) were analyzed …

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Machine Learning For A Vernier-Effect-Based Optical Fiber Sensor, Chen Zhu, Osamah Alsalman, Wassana Naku May 2023

Machine Learning For A Vernier-Effect-Based Optical Fiber Sensor, Chen Zhu, Osamah Alsalman, Wassana Naku

Electrical and Computer Engineering Faculty Research & Creative Works

In recent years, the optical Vernier effect has been demonstrated as an effective tool to improve the sensitivity of optical fiber interferometer-based sensors, potentially facilitating a new generation of highly sensitive fiber sensing systems. Previous work has mainly focused on the physical implementation of Vernier-effect-based sensors using different combinations of interferometers, while the signal demodulation aspect has been neglected. However, accurate and reliable extraction of useful information from the sensing signal is critically important and determines the overall performance of the sensing system. In this Letter, we, for the first time, propose and demonstrate that machine learning (ML) can be …

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Simultaneous And Multiplexed Measurement Of Curvature And Strain Based On Optical Fiber Fabry-Perot Interferometric Sensors, Chen Zhu, Hongkun Zheng, Osamah Alsalman, Wassana Naku, Lingmei Ma May 2023

Simultaneous And Multiplexed Measurement Of Curvature And Strain Based On Optical Fiber Fabry-Perot Interferometric Sensors, Chen Zhu, Hongkun Zheng, Osamah Alsalman, Wassana Naku, Lingmei Ma

Electrical and Computer Engineering Faculty Research & Creative Works

Optical fiber sensors that have a compact size and the capability for multi-parameter sensing are desired in various applications. This article reports a miniaturized optical fiber Fabry-Perot interferometric sensor with a length of hundreds of µm that is able to simultaneously measure variations of curvature, temperature, and strain. The sensor is easy to fabricate, requiring only the fusion splicing of a short section of the silica capillary tube between two single-mode fibers (SMFs). The combined mechanism of the Fabry-Perot interference occurred in the two interfaces between the capillary and the SMFs, and the Anti resonant guidance induced by the capillary …

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Design And Analysis Of Gold-Nanowires Based Multi-Channel Spr Sensor, Nasir Mahmood Anjum, Farhan Mumtaz, Muhammad Aqueel Ashraf May 2023

Design And Analysis Of Gold-Nanowires Based Multi-Channel Spr Sensor, Nasir Mahmood Anjum, Farhan Mumtaz, Muhammad Aqueel Ashraf

Electrical and Computer Engineering Faculty Research & Creative Works

This research reports the simultaneous multi-analyte sensing capabilities of a D-shaped multi-channel surface plasmon resonance (SPR) sensor. Three channels are truncated in a U-shaped pattern at the side-polished surface of the D-shaped three-core fiber. Three Gold-nanowires (AuNWs) are positioned at the bottom of each sensing channel. To examine the SPR sensor's multi-channel characteristics, a finite element method (FEM) is applied. In order to detect a variety of analytes, y-polarized modes-multiplexing is used, which offers a sufficient wavelength range. At an infiltrated refractive index (RI) of 1.35, 1.38, and 1.41, respectively, the maximal RI sensitivities of c-1 (channel-one), c-2 (channel-two), and …

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