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Grain Size And Texture Effects On Deformation Behavior Of Az31 Magnesium Alloy, W. Yuan, R. S. Mishra Dec 2012

Grain Size And Texture Effects On Deformation Behavior Of Az31 Magnesium Alloy, W. Yuan, R. S. Mishra

Materials Science and Engineering Faculty Research & Creative Works

Cold rolled AZ31 magnesium alloy sheet was subjected to friction stir processing to generate four average grain sizes ranging from 0.8 to 9.6 μm. the processed material exhibited a strong basal fiber texture with the c-axis tilted about 35-55° towards the processing direction. the grain size and texture dependence of mechanical behavior were evaluated by using tensile testing along two orthogonal directions. Remarkably high ductility of ~65% was achieved in relatively coarse-grained material that fractured without developing necking when tested in the processing direction. the ductility decreased significantly to ~10% for ultrafine grained material as the tensile yield strength increased …

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Secure Hierarchical Data Aggregation In Wireless Sensor Networks: Performance Evaluation And Analysis, Vimal Kumar, Sanjay Kumar Madria Dec 2012

Secure Hierarchical Data Aggregation In Wireless Sensor Networks: Performance Evaluation And Analysis, Vimal Kumar, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

Secure data aggregation in wireless sensor networks has two contrasting objectives, i) Efficiently collecting and aggregating data and ii) Aggregating the data securely. Many schemes do not take into account the possibility of corrupt aggregators and allow the aggregator to decrypt data in hop-by-hop algorithms. on the other hand, using public key cryptography for providing end to end security is not energy efficient. in this paper we present and analyze the performance of the secure hierarchical data aggregation algorithm which uses an efficient public key cryptosystem (elliptic curve cryptography) to achieve end to end security. Unlike many other secure data …

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Crowdsourcing: Dynamic Data Management In Mobile P2p Networks, Sanjay Kumar Madria, Anirban Mondal Dec 2012

Crowdsourcing: Dynamic Data Management In Mobile P2p Networks, Sanjay Kumar Madria, Anirban Mondal

Computer Science Faculty Research & Creative Works

No abstract provided.

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Trust Management Of Encrypted Data Aggregation In A Sensor Network Environment, Nayot Poolsappasit, Michael Busby, Sanjay Kumar Madria Dec 2012

Trust Management Of Encrypted Data Aggregation In A Sensor Network Environment, Nayot Poolsappasit, Michael Busby, Sanjay Kumar Madria

Computer Science Faculty Research & Creative Works

Efficient power management is vital for increasing the life of sensor nodes in wireless sensor networks (WSN). Thus, techniques such as data aggregation have been widely used in WSN to preserve nodes' energy. Despite its appealing and powerful features, data aggregation processes require a high level of security. Ensuring accuracy with aggregating data can become an issue even due to single bit errors. Hence, many encryption techniques have been proposed to secure the data aggregation process. However, once a wireless sensor is physically compromised, the keys stored on the sensor are exposed, thus rendering the cryptography useless. Moreover, most cryptographic …

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Capacitance Calculation Of Tsvs Using An Integral Equation Method Based On Partial Capacitances, Hanfeng Wang, Yaojiang Zhang, Albert E. Ruehli, Jun Fan Dec 2012

Capacitance Calculation Of Tsvs Using An Integral Equation Method Based On Partial Capacitances, Hanfeng Wang, Yaojiang Zhang, Albert E. Ruehli, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

An integral equation method based on partial capacitances is used to extract the capacitance between two through-silicon-vias (TSVs). the unrealistic assumption of equal potential along the vertical interface of silicon dioxide (SiO2) coating of TSVs in the analytical method has been removed by introducing unknown equivalent charges. the Galerkin method is used here to solve the unknown charge densities in the integral equation and thus, the capacitance between two TSVs can be efficiently calculated. the results are validated by comparing the extracted capacitances with commercial software based on the finite element method. the accuracy and efficiency have been demonstrated. © …

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Asic Package Design Optimization For 10 Gbps And Above Backplane Serdes Links, Jane Lim, Kai Soon Chow, Jiangfan Zhang, Jianmin Zhang, Kelvin Qiu, Rick Brooks Dec 2012

Asic Package Design Optimization For 10 Gbps And Above Backplane Serdes Links, Jane Lim, Kai Soon Chow, Jiangfan Zhang, Jianmin Zhang, Kelvin Qiu, Rick Brooks

Electrical and Computer Engineering Faculty Research & Creative Works

This paper discussed the package selection and BGA signal pin assignment consideration for high-end ASIC design with over 400 SerDes (Serializer Deserializer) pairs for >10Gbps backplane interface. the ASIC package is using advanced high-performance organic build-up (BU) materials like GX13, GZ41 and thinner core in the stack-up to help reduce the package loss and improve the signal transmission on the highspeed SerDes links. for return loss and insertion loss studies, the main objectives are to investigate the core thickness, BU material properties, and routing configurations impact on the differential signaling. the design suggestions are then made at each area for …

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Speed-Up Of Peec Em/Ckt Solver Using Rank-Reduced Waveform Relaxation, Giulio Antonini, Albert E. Ruehli Dec 2012

Speed-Up Of Peec Em/Ckt Solver Using Rank-Reduced Waveform Relaxation, Giulio Antonini, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

The solution of EM/Circuit problems is important for the EMC/SI/PI system designs. an essential issue today is the solution of larger problems without excessive memory and compute time requirements. in this paper, we show the potential for a new speed-up approach using the PEEC method. One source of the speed-up is due to the use of the waveform relaxation (WR) technique, which is very suitable for parallel processing. Importantly, the dense part of the partial inductance and potential matrices are sparsified by taking advantage of the rank deficiency of the dense parts of the MNA matrix. We show that both …

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Using Fsv In High-Speed Channel Characterization And Correlation, Jiangfan Zhang, Jianmin Zhang, Jane Lim, Kelvin Qiu, Rick Brooks, Bill Chen Dec 2012

Using Fsv In High-Speed Channel Characterization And Correlation, Jiangfan Zhang, Jianmin Zhang, Jane Lim, Kelvin Qiu, Rick Brooks, Bill Chen

Electrical and Computer Engineering Faculty Research & Creative Works

In modern high performance networking systems, high-speed channels are among the most concerns due to the channel loss, discontinuities and crosstalk as data rate reaches 15 Gbps (Gigabit per second) and above through backplane. Full-wave modeling and system level simulations are widely used to estimate the performance for high-speed channels. Due to the variations and uncertainties associated with the simulation and manufacturing, correlation between simulation and measurement is often used to gain confidence on the channel performance prediction. in this paper, a high-speed channel including the portion inside a high-end ASIC (Application-Specific Integrated Circuit) package and the portion on a …

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Fast Admittance Computation For Tsv Arrays, Dazhao Liu, Siming Pan, Brice Achkir, Jun Fan Dec 2012

Fast Admittance Computation For Tsv Arrays, Dazhao Liu, Siming Pan, Brice Achkir, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

A fast method to calculate the admittance matrix of through Silicon Vias (TSVs) is proposed in this paper. the silicon dioxide layers are equivalently modelled using the bound charge on the conductor surfaces as well as on the dielectric interface between the silicon dioxide and the silicon regions. Unknown surface densities of both the free and bound charge are expanded using the axial harmonics. Galerkin's method is then applied to obtain the capacitance and conductance matrices. the proposed method is validated with a full wave 2D cross-sectional analysis tool for a typical TSV pair structure. Comparisons with popular closed-form expressions …

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Alternative Aefie-Efie Method For Broadband Cem Modeling, Jia Liu, Li (Lijun) Jun Jiang Dec 2012

Alternative Aefie-Efie Method For Broadband Cem Modeling, Jia Liu, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

It is well known that the electric field integral equation (EFIE) has the low frequency breakdown problem while the Augmented electric field integral equation (AEFIE) method has the high frequency breakdown issue. To obtain a unified method that works for both low and high frequencies without manual switching of methods, a novel and simple method is proposed in this paper. It uses AEFIE and EFIE to compensate each other iteratively in all frequency regimes to guarantee the accuracy of the solution. As a result, it effectively extends AEFIE to the high frequency regime and extends EFIE to the low frequency …

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Electromagnetic Properties Of Metal Granular Composite Materials For Emc Applications, Takanori Tsutaoka, Aiko Tsurunaga, Teruhiro Kasagi, Kenichi Hatakeyama, Marina Koledintseva Dec 2012

Electromagnetic Properties Of Metal Granular Composite Materials For Emc Applications, Takanori Tsutaoka, Aiko Tsurunaga, Teruhiro Kasagi, Kenichi Hatakeyama, Marina Koledintseva

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic properties of copper and Fe55Ni45alloy (Permalloy) composite materials have been studied by measuring the relative complex permeability (µr = µr’– jµr”), and permittivity (Σr = Σr’– jΣr”) spectra over the microwave range, as well as the a.c. electrical conductivity σac spectra. The variation of σac and Σr with particle content shows the insulator-metal transition due to the percolation effect. The effective cluster model can be applied to the percolation effect in permittivity. The permeability spectra in Permalloy composites, which contain the percolated particles, …

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Analytical Representations For Frequency Dependences Of Microwave Permeability, Konstantin N. Rozanov, Marina Koledintseva Dec 2012

Analytical Representations For Frequency Dependences Of Microwave Permeability, Konstantin N. Rozanov, Marina Koledintseva

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic materials applied to solve various EMC and EMI problems require adequate analytical description of their RF and microwave material parameters. This is necessary for numerical optimization of wideband electromagnetic performance of devices incorporating these materials. The paper discusses the shape of frequency dependences of microwave permeability in homogeneous materials and composites. The Lorentzian frequency dispersion law is shown to allow for rather accurate description of all types of magnetic loss peaks, including those related to the ferromagnetic resonance and the effect of eddy currents. To model wideband electromagnetic performance of composites, mixing laws are typically used. The problem is …

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Economics Of Grid-Tied Customer-Owned Photovoltaic Power Generation, Badrul H. Chowdhury, Fanjun Meng Dec 2012

Economics Of Grid-Tied Customer-Owned Photovoltaic Power Generation, Badrul H. Chowdhury, Fanjun Meng

Electrical and Computer Engineering Faculty Research & Creative Works

Currently, there are only a handful of methods used to calculate prices for the energy generated from photovoltaic and other renewable resources. Some of these are net metering, feed-in-tariffs, etc. However, none of the methods in use today are widely used. This paper will discuss a new methodology to calculate energy prices in the sense of locational marginal prices for future smart distribution systems with renewable energy resources as the primary energy supply. the scheme calculates the marginal energy price for renewable generations and storage, as well as the marginal congestion and loss prices in order to determine optimal economic …

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Towards On-Line Voltage Stability Assessment Using Synchrophasors, Himanshu S. Hirlekar, Badrul H. Chowdhury Dec 2012

Towards On-Line Voltage Stability Assessment Using Synchrophasors, Himanshu S. Hirlekar, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

Advances in technology has made possible the online monitoring and assessment of voltage stability. Synchrophasors measure voltage and current phasors with accurate time stamping with respect to Global Positioning System (GPS) clock reference. a novel voltage stability prediction algorithm using synchrophasors is proposed. Synchrophasor data is used to perform a fast state estimation of the system. This is a departure from conventional SCADA-Based state estimation. the traditional method of VQ analysis for voltage stability is put to use in this algorithm to estimate the voltage stability margin. Since the data refresh rate is faster with synchrophasor data than SCADA-Based data, …

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Solid State Fault Interruption Devices In Medium Voltage Microgrid Distribution Systems With Distributed Energy Resources, Mehul K. Madan, Badrul H. Chowdhury Dec 2012

Solid State Fault Interruption Devices In Medium Voltage Microgrid Distribution Systems With Distributed Energy Resources, Mehul K. Madan, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

The solid-state fault interruption device (SSFID) is used for the purpose of quickly isolating sections of power networks under permanent faults. the SSFID is tested for performance by simulation in a simulated medium voltage system. a comparison with the conventional breaker is presented in response to system faults in the presence of wind power plants and other distributed energy resources. the SSFID appears to be a superior alternative to the contemporary mechanical circuit breaker in isolating faulted sections. However, some high transients may appear on the network because of the operation of the device. © 2012 IEEE.

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Microgrids - A Review Of Modeling, Control, Protection, Simulation And Future Potential, Shyam Naren Bhaskara, Badrul H. Chowdhury Dec 2012

Microgrids - A Review Of Modeling, Control, Protection, Simulation And Future Potential, Shyam Naren Bhaskara, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

Results of a literature survey done on microgrids from conception to installation is presented. the purpose is to evaluate the current status, major obstacles and existing research efforts directed toward establishing functional microgrids within utility systems. This review paper covers technical issues associated with frequency control and re-synchronization associated with typical distributed energy sources. Also evaluated are regulatory and policy issues associated with ownership, maintenance, availability, coordinated equipment control, obligation to provide adequate power quality, etc. associated with operating an islanded microgrid within a utility company's service territory. Actual microgrids in operation today are described. Benchmark test systems for steady …

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Recovery Of Metallic Materials From Printed Wiring Boards By Green Pyrolysis Process, Alex Luyima, Lifeng Zhang, Jaan Kers, Viktor Laurmaa Dec 2012

Recovery Of Metallic Materials From Printed Wiring Boards By Green Pyrolysis Process, Alex Luyima, Lifeng Zhang, Jaan Kers, Viktor Laurmaa

Materials Science and Engineering Faculty Research & Creative Works

Currently, the main options for the treatment of electronic waste are involved in reuse, remanufacturing, and recycling, as well as incineration and land filling. Recycling of e-waste can be broadly divided into three major steps: (a) disassembly: selectively disassembly, targeting on singling out hazardous or valuable components for special treatment, is an indispensable process in recycling of e-waste; (b) upgrading: using mechanical processing and/or metallurgical processing to up-grade desirable materials content, i. e. preparing materials for refining process; (c) refining: in the last step, recovered materials are retreated or purified by using chemical (metallurgical) processing so as to be acceptable …

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Distribution System Operation With Solid State Controller And Energy Storage Management, F. Meng, D. Shah, B. H. Chowdhury, M. L. Crow Dec 2012

Distribution System Operation With Solid State Controller And Energy Storage Management, F. Meng, D. Shah, B. H. Chowdhury, M. L. Crow

Electrical and Computer Engineering Faculty Research & Creative Works

A novel distribution system infrastructure is proposed with solid state controller locating at load sites. an energy storage management algorithm is developed to optimize battery charge/discharge operation using forward dynamic programming method. This algorithm is implemented in a system test bed in PSCAD. the simulation results present economic benefits to private customers with reduced energy cost. It also reduces system peak demand which may improve system reliability. © 2012 IEEE.

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A Circular Polarization Hybrid-Integrated Rectangular Ring Antenna For Rfid Reader, Yan Li, Sheng Sun, Lijun Jiang, Terry T. Ye Dec 2012

A Circular Polarization Hybrid-Integrated Rectangular Ring Antenna For Rfid Reader, Yan Li, Sheng Sun, Lijun Jiang, Terry T. Ye

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a compact hybrid-integrated microstrip rectangular ring antenna with circular polarization is proposed for RFID reader. By integrating a cross-slotted patch hybrid with a rectangular ring antenna in the same plane, the proposed antenna has the features of circular polarization, compact size, low cost, light weight and unique flexibility for RFID applications. A prototype operating at 915 MHz is designed and fabricated. The measured results agree well with the simulated results. © 2012 IEEE.

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Reliability Evaluation Of Distribution Systems Containing Renewable Distributed Generations, Abdulaziz A. Alkuhayli, Srinath Raghavan, Badrul H. Chowdhury Dec 2012

Reliability Evaluation Of Distribution Systems Containing Renewable Distributed Generations, Abdulaziz A. Alkuhayli, Srinath Raghavan, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

Reliability evaluation of distribution networks under grid-tied and islanded microgrid modes is presented. the Monte Carlo simulation (MCS) algorithm is applied to a modified RBTS Bus 2 distribution network. the network includes three types of distributed energy resources, namely, solar photovoltaic (PV), wind turbine (WT), and diesel turbine generator (DTG). These distributed generators contribute to supply part of the load during grid-connected mode but supply 100% of the load in the islanded microgrid mode. This study shows that the implementation of distributed generations can improve the reliability indices of the distribution network. © 2012 IEEE.

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Implementation Of A Microgrid Central Controller In A Laboratory Microgrid Network, Md Rasheduzzaman, Shyam N. Bhaskara, Badrul H. Chowdhury Dec 2012

Implementation Of A Microgrid Central Controller In A Laboratory Microgrid Network, Md Rasheduzzaman, Shyam N. Bhaskara, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

When distributed generation (DG) units operate in a microgrid environment, there is a need for coordinated operation between the DGs, the utility grid and the loads. a Microgrid Central Controller (MGCC) can keep track of the status from the systemic point of view and command the local micro source controllers (MC) to ensure system stability. in various modes of operation, vis-à-vis grid-connected, islanded and during transition from grid-connected to islanded mode and vice versa, the MGCC can support the MCs by feeding the necessary information to contribute towards stable system operation. This paper discusses the implementation of the MGCC for …

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Developing Life Cycle Management Plans For Power Plant Components, Srinath Raghavan, Badrul H. Chowdhury Dec 2012

Developing Life Cycle Management Plans For Power Plant Components, Srinath Raghavan, Badrul H. Chowdhury

Electrical and Computer Engineering Faculty Research & Creative Works

A process to develop life cycle management (LCM) plans for power plant components is described. an LCM plan is a guide to make operational decision for a piece of equipment over its life cycle. an LCM typically consists of preventive maintenance schedule, condition monitoring and inspection activities, replacement or refurbishment plans and spares management. It is developed on the basis of component failure modes, operating history, maintenance practices, ageing, spares and obsolescence. Once an LCM plan has been formulated it can be compared with other alternative LCM strategies in order to minimize the long-term costs over the plant lifetime. for …

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Fokker-Planck Equation Application To Analysis Of A Simplified Wind Turbine Model, Keyou Wang, Mariesa L. Crow Dec 2012

Fokker-Planck Equation Application To Analysis Of A Simplified Wind Turbine Model, Keyou Wang, Mariesa L. Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a new method to evaluate the stochastic dynamic model of the wind turbine system using stochastic differential equations (SDE). the wind speed is described by the Rayleigh distribution which is constructed as the stationary solution of a one-dimensional nonlinear SDE. the dynamic model of the wind turbine system can be combined with this SDE of wind speed to expand to multi-dimensional stochastic differential equations. the time evolution of the probability density function of the system is described by the Fokker-Planck equation (FPE) which can be derived from the corresponding stochastic differential equations. the procedure is illustrated using …

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Enabling Wind Power Plants With Frequency And Voltage Regulation Capability By Forced Curtailment, Anshuman Vaidya, Badrul H. Chowdhury, Manohar Chamana Dec 2012

Enabling Wind Power Plants With Frequency And Voltage Regulation Capability By Forced Curtailment, Anshuman Vaidya, Badrul H. Chowdhury, Manohar Chamana

Electrical and Computer Engineering Faculty Research & Creative Works

With higher penetration of renewable energy resources like wind energy, its utilization for the provision of ancillary services, such as frequency and voltage regulation, is imminent. This paper deals with allowing the wind power plant to provide these services in a microgrid environment with the consideration of different generation mixes of wind and conventional energy resources. a novel hysteresis control algorithm is implemented in the wind control system to compensate for the shortcomings of droop control during low wind conditions. a microgrid model test system is simulated in Matlab/Simulink environment to compare the performance of the control strategy, henceforth called …

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An Automated Forward Operating Base Electrical Distribution System Simulator, Onur Kahveci, Mariesa L. Crow, Steven Corns Dec 2012

An Automated Forward Operating Base Electrical Distribution System Simulator, Onur Kahveci, Mariesa L. Crow, Steven Corns

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, an automated forward operating base electrical distribution system simulator (ODCC) is developed. the ODCC has been developed based on the open platform distribution system simulator (DSS) that is able to create variable models of electrical systems and performing many types of analysis. © 2012 IEEE.

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The Far Field Transformation Using The Iterative Srm Based On The Phaseless Data, Ping Li, Li (Lijun) Jun Jiang Dec 2012

The Far Field Transformation Using The Iterative Srm Based On The Phaseless Data, Ping Li, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Conventional equivalent source reconstruction methods (SRM) require both phase and amplitude information of the field data. However, there are situations where the phase information is not easy to obtain. Hence, developing novel SRM based on phaseless data is necessary. In this paper, a novel iterative SRM based on two sets of measured phaseless data is presented. It can reproduce the 3D radiation pattern with very good accuracy. Integral equation (IE) is employed to build reconstruct equivalent source. Combined field IE (CFIE) is also employed to obtain more physical current distribution. © 2012 IEEE.

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A Single-Layer Compact Hf-Uhf Dual-Band Rfid Tag Antenna, Zi Long Ma, Li (Lijun) Jun Jiang, Jingtian Xi, Terry Tao Ye Dec 2012

A Single-Layer Compact Hf-Uhf Dual-Band Rfid Tag Antenna, Zi Long Ma, Li (Lijun) Jun Jiang, Jingtian Xi, Terry Tao Ye

Electrical and Computer Engineering Faculty Research & Creative Works

This letter presents a novel dual-band (HF and UHF) radio frequency identification (RFID) tag antenna. Two key challenges are faced: the compact dimension and the impaired bandwidth due to the couplings between two band structures. To enable the implementation of whole design on a credit-card-size single-layer support, a spiral coil along the edges of the card is designed to handle the HF (13.56 MHz) near-field coupling, and the UHF antenna is placed inside the coil instead of outside. Meanwhile, a diagonal symmetric design consisting of two meander lines inside the spiral coil is adopted for UHF band. This structure supports …

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Integral Equation Method For Analyzing Purcell Effect In Plasmonic System, Yongpin P. Chen, Weng Cho Chew, Wei E.I. Sha, W. C.H. Choy, Lijun Jiang Dec 2012

Integral Equation Method For Analyzing Purcell Effect In Plasmonic System, Yongpin P. Chen, Weng Cho Chew, Wei E.I. Sha, W. C.H. Choy, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Integral equation method is applied to analyze the Purcell effect in plasmonic system in this paper. By applying the Fermi's golden rule, the Purcell effect of a quantum emitter can be calculated from the local density of states (LDOS), which can be further expressed by the imaginary part of the Green's function of the whole system. To obtain this Green's function numerically, the layered medium Green's function is utilized to simplify the modeling of planarly layered substrate, where the surface plasmon polaritons (SPPs) can be sustained. The metallic nano scatterers are introduced to excite the localized surface plasmons (LSP), and …

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Characterization Of Wave Physics Using The Rigorous Helmholtz Decomposition Based On The Surface Integral Equation, Xiaoyan Y.Z. Xiong, Wei E.I. Sha, Li (Lijun) Jun Jiang Dec 2012

Characterization Of Wave Physics Using The Rigorous Helmholtz Decomposition Based On The Surface Integral Equation, Xiaoyan Y.Z. Xiong, Wei E.I. Sha, Li (Lijun) Jun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Helmholtz decomposition (HD) is a fundamental tool of vector calculus and plays an important role in electromagnetics. In this work, arbitrary vector field defined on the open or closed surface is decomposed into the sum of an irrotational (curl-free) vector field and a solenoidal (divergence-free) vector field by using the surface integral equation method. Unlike the popular loop-tree decomposition that is only a quasi-HD suitable for the circuit physics in the low frequency regime, the HD developed in this paper is rigorous and can capture both circuit and wave physics from very low frequency to high frequency regimes. The work …

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An Efficient Method For Highly Oscillatory Physical Optics Integrals, Yu Mao Wu, Li (Lijun) Jun Jiang, Weng Cho Chew Dec 2012

An Efficient Method For Highly Oscillatory Physical Optics Integrals, Yu Mao Wu, Li (Lijun) Jun Jiang, Weng Cho Chew

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, we use the steepest descent path (SDP) method in the complex analysis to calculate the highly oscillatory physical optics (PO) integral with quadratic phase and amplitude variations on the triangular patch. Compared with traditional approximate asymptotic expansion approach, our method has significantly improved the PO integral accuracy by one to two digits (10 1 to 102) for evaluating the PO integral. Moreover, the computation effort for the highly oscillatory integral is frequency independent. © 2012 IEEE.

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