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Real Time State Estimation Of Multi-Converter More Electric Ship Power Systems Using The Generalized State Space Averaging Method, Madan M. Jalla, Ali Emadi, Geoffrey A. Williamson, Babak Fahimi Dec 2004

Real Time State Estimation Of Multi-Converter More Electric Ship Power Systems Using The Generalized State Space Averaging Method, Madan M. Jalla, Ali Emadi, Geoffrey A. Williamson, Babak Fahimi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a real time state estimation algorithm for control and security maintenance of multi-converter MES power electronic systems. Estimation of the state variables of the system includes the effects of ripples and converter switching actions. the proposed state estimator is based on the Weighted Least Squares (WLS) approach. Generalized state space averaging technique in which we consider the DC value of the state variables, and their harmonics is used to model DC/DC converters for the state estimator. in this paper, after introducing the proposed approach and the concept of security and control assessments, results of applying the proposed …


Evaluating The Repair Of System-On-Chip (Soc) Using Connectivity, Minsu Choi, Nohpill Park, Vincenzo Piuri, Fabrizio Lombardi Dec 2004

Evaluating The Repair Of System-On-Chip (Soc) Using Connectivity, Minsu Choi, Nohpill Park, Vincenzo Piuri, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a new model for analyzing the repairability of reconfigurable system-on-chip (RSoC) instrumentation with the repair process. It exploits the connectivity of the interconnected cores in which unreliability factors due to both neighboring cores and the interconnect structure are taken into account. Based on the connectivity, two RSoC repair scheduling strategies, Minimum Number of Interconnections First (I-MIN) and Minimum Number of Neighboring Cores First (C-MIN), are proposed. Two other scheduling strategies, Maximum Number of Interconnections First (I-MAX) and Maximum Number of Neighboring cores First (C-MAX), are also introduced and analyzed to further explore the impact of connectivity-based repair …


Analysis And Control Of A Buck Dc-Dc Converter Operating With Constant Power Load In Sea And Undersea Vehicles, Claudio Rivetta, Ali Emadi, Geoffrey A. Williamson, Ranjit Jayabalan, Babak Fahimi Dec 2004

Analysis And Control Of A Buck Dc-Dc Converter Operating With Constant Power Load In Sea And Undersea Vehicles, Claudio Rivetta, Ali Emadi, Geoffrey A. Williamson, Ranjit Jayabalan, Babak Fahimi

Electrical and Computer Engineering Faculty Research & Creative Works

Power electronics based zonal DC power distribution systems are being considered for sea and undersea vehicles. the stability of the DC power electronics-based power distribution systems is a significant design consideration because of the potential for negative impedance induced instabilities. in this paper, dynamic properties and control of a buck converter feeding a downstream DC-DC converter are studied. the controller in this system combines an instantaneous current feedback loop using hysteresis with a proportional-integral algorithm to regulate the output voltage of the converter. based on a large-signal averaged model of the converter, the stability-in-large around the operation point is presented. …


Modeling Of Multi-Converter More Electric Ship Power Systems Using The Generalized State Space Averaging Method, Madan M. Jalla, Ali Emadi, Geoffrey A. Williamson, Babak Fahimi Dec 2004

Modeling Of Multi-Converter More Electric Ship Power Systems Using The Generalized State Space Averaging Method, Madan M. Jalla, Ali Emadi, Geoffrey A. Williamson, Babak Fahimi

Electrical and Computer Engineering Faculty Research & Creative Works

based on the more electric ship (MES) concept, conventional mechanical, hydraulic, and pneumatic power transfer systems are replaced by electrical systems in different sea vehicles. Considering different levels of power requirements of various electrical loads and for the achievement of compact, light, safe, and efficient power supplies, implementation of multi-converter power electronics-based power systems is the most feasible option in the development of advanced navy vehicles. This paper presents a modular approach for the modeling and simulation of multiconverter MES power systems based on the generalized state space averaging method. MES power systems may consist of many individual converters connected …


Applications Of Power Electronics-Based Systems In Vehicular Technology: State-Of-The-Art And Future Trends, R. Jayabalan, Babak Fahimi, A. Koenig, Steven Pekarek Nov 2004

Applications Of Power Electronics-Based Systems In Vehicular Technology: State-Of-The-Art And Future Trends, R. Jayabalan, Babak Fahimi, A. Koenig, Steven Pekarek

Electrical and Computer Engineering Faculty Research & Creative Works

Power electronics-Based systems and components have been increasingly used in land, air, and sea vehicles over the past decade. This has turned the vehicular products into a primary market for power electronics applications. Moreover, the existing trend in more electrification of the vehicles represents an even bigger potential for an increase in the existing demand. Although the primary incentive for introduction of multi-converter systems into vehicular technologies was to enhance fuel economy and environmental issues associated with vehicles; today, improvement of fault tolerance, cost, and compactness have boosted the motivation for development of the more electric vehicles. the use of …


Versatile Hardware And Software Tools For Educating Students In Power Electronics, Joshua M. Williams, James L. Cale, Nicholas D. Benavides, Jeff D. Wooldridge, Andreas C. Koenig, Jerry L. Tichenor, Steven D. Pekarek Nov 2004

Versatile Hardware And Software Tools For Educating Students In Power Electronics, Joshua M. Williams, James L. Cale, Nicholas D. Benavides, Jeff D. Wooldridge, Andreas C. Koenig, Jerry L. Tichenor, Steven D. Pekarek

Electrical and Computer Engineering Faculty Research & Creative Works

A new power electronics laboratory has been constructed at the University of Missouri - Rolla. Key components of the laboratory are a set of custom- designed hardware and software tools. the novel hardware tools include five mobile power electronics testbeds that each contain the semiconductor devices, gate-drive boards, voltage and current sensors, and computer interface connections required to study a wide range of circuit topologies and control techniques. Novel software tools include a set of virtual instruments used for control, data capture, and data analysis. a description of these tools, along with their use in power electronics courses, laboratory exercises, …


An Error Analysis Of The Multirate Method For Power System Transient Stability Simulation, Jingjia Chen, Mariesa Crow, Badrul H. Chowdhury, Levent Acar Oct 2004

An Error Analysis Of The Multirate Method For Power System Transient Stability Simulation, Jingjia Chen, Mariesa Crow, Badrul H. Chowdhury, Levent Acar

Electrical and Computer Engineering Faculty Research & Creative Works

This efficient application of any numerical integration method depends on accurate estimation of the local truncation error to govern step size control. In this paper, the local truncation error of the multirate method using the forward Euler integration is derived leading to the calculation of the optimal step ratio. The techniques of applying multirate method in power systems are discussed. By implementing the multirate method in a practical power system example, the multirate strategies are proved to be efficient compared with traditional simulation methods.


Electrical Material Property Measurements Using A Free-Field, Ultra-Wideband System [Dielectric Measurements], C. A. Grosvenor, R. Johnk, D. Novotny, S. Canales, J. Baker-Jarvis, M. Janezic, James L. Drewniak, Marina Koledintseva, Jianmin Zhang, Poorna Chander Ravva Oct 2004

Electrical Material Property Measurements Using A Free-Field, Ultra-Wideband System [Dielectric Measurements], C. A. Grosvenor, R. Johnk, D. Novotny, S. Canales, J. Baker-Jarvis, M. Janezic, James L. Drewniak, Marina Koledintseva, Jianmin Zhang, Poorna Chander Ravva

Electrical and Computer Engineering Faculty Research & Creative Works

We present nondestructive measurements of material properties using TEM horn antennas and an ultra-wideband measurement system. Time-domain gating and genetic algorithms are used to process the data and extract the dielectric properties of the material under test.


Landmine Detection And Discrimination Using High-Pressure Waterjets, Daryl G. Beetner, R. Joe Stanley, Sanjeev Agarwal, Deepak R. Somasundaram, Kopal Nema, Bhargav Mantha Oct 2004

Landmine Detection And Discrimination Using High-Pressure Waterjets, Daryl G. Beetner, R. Joe Stanley, Sanjeev Agarwal, Deepak R. Somasundaram, Kopal Nema, Bhargav Mantha

Electrical and Computer Engineering Faculty Research & Creative Works

Methods of locating and identifying buried landmines using high-pressure waterjets were investigated. Methods were based on the sound produced when the waterjet strikes a buried object. Three classification techniques were studied, based on temporal, spectral, and a combination of temporal and spectral approaches using weighted density distribution functions, a maximum likelihood approach, and hidden Markov models, respectively. Methods were tested with laboratory data from low-metal content simulants and with field data from inert real landmines. Results show that the sound made when the waterjet hit a buried object could be classified with a 90% detection rate and an 18% false …


Modeling Yield Of Carbon-Nanotube/Silicon-Nanowire Fet-Based Nanoarray Architecture With H-Hot Addressing Scheme, Shanrui Zhang, Minsu Choi, Nohpill Park Oct 2004

Modeling Yield Of Carbon-Nanotube/Silicon-Nanowire Fet-Based Nanoarray Architecture With H-Hot Addressing Scheme, Shanrui Zhang, Minsu Choi, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

With molecular-scale materials, devices and fabrication techniques recently being developed, high-density computing systems in the nanometer domain emerge. An array-based nanoarchitecture has been recently proposed based on nanowires such as carbon nanotubes (CNTs) and silicon nanowires (SiNWs). High-density nanoarray-based systems consisting of nanometer-scale elements are likely to have many imperfections; thus, defect-tolerance is considered one of the most significant challenges. In this paper we propose a probabilistic yield model for the array-based nanoarchitecture. The proposed yield model can be used (1) to accurately estimate the raw and net array densities, and (2) to design and optimize more defect and fault-tolerant …


Bulk Power System Low Frequency Oscillation Suppression By Facts/Ess, Li Zhang, Y. Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow Oct 2004

Bulk Power System Low Frequency Oscillation Suppression By Facts/Ess, Li Zhang, Y. Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Low frequency oscillations in the interconnected power systems are observed all around the world. In this paper, the authors studied the inter-area mode low frequency oscillations by analyzing the phenomena in Nashville area of the Tennessee Valley Authority (TVA) system. Our study revealed 4 dynamic groups of generators in this area. Within each group, generators swing together and have the same dynamic trend. Generators from different dynamic groups swing against each other. The authors studied the possibility of using a FACTS/ESS controller to damp the low frequency oscillations in Nashville area. The active power is controlled to damp the low …


Eaf Voltage Flicker Mitigation By Facts/Ess, Li Zhang, Yilu Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow Oct 2004

Eaf Voltage Flicker Mitigation By Facts/Ess, Li Zhang, Yilu Liu, Michael R. Ingram, Dale T. Bradshaw, Steve Eckroad, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

One of the problems caused by an electrical arc furnace (EAF) is voltage fluctuation from the variations of the active and reactive furnace load, which are known as voltage flickers. In this paper, voltage flicker mitigation results by different FACTS and energy storage systems (ESS) were presented. The system X/R ratio looking from the point of common coupling, which has a special impact on the effectiveness of active compensation, was discussed. The study has clarified the misunderstanding of how the system X/R ratio should be calculated. The study showed that FACTS with ESS could play a better role than reactive …


Evaluating Conduction Loss Of A Parallel Igbt-Mosfet Combination, Jonathan W. Kimball, Patrick L. Chapman Oct 2004

Evaluating Conduction Loss Of A Parallel Igbt-Mosfet Combination, Jonathan W. Kimball, Patrick L. Chapman

Electrical and Computer Engineering Faculty Research & Creative Works

A variety of power devices are available to designers, each with specific advantages and limitations. For inverters, typically an IGBT combined with a p-i-n diode is used to obtain high current density. Recent developments in high-voltage MOSFETs support other alternatives. For example, a MOSFET can be paralleled with an IGBT to reduce losses at low currents, while the IGBT carries the load at high currents. The current work evaluates conduction losses in this configuration, showing applicability to generic inverters.


Extended Operation Of Flying Capacitor Multilevel Inverters, Jing Huang, Keith Corzine Oct 2004

Extended Operation Of Flying Capacitor Multilevel Inverters, Jing Huang, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

Recent research in flying capacitor multilevel inverters (FCMIs) has shown that the number of voltage levels can be extended by changing the ratio of the capacitor voltages. For the three-cell FCMI, four levels of operation are expected if the traditional ratio of the capacitor voltages is 1:2:3. However, by altering the ratio, the inverter can operate as a five-, six-, seven-, or eight-level inverter. According to previous research, the eight-level case is referred to as maximally distended (or full binary combination schema) since it utilizes all possible transistor switching states. However, this case does not have enough per-phase redundancy to …


Probabilistic Balancing Of Fault Coverage And Test Cost In Combined Built-In Self-Test/Automated Test Equipment Testing Environment, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi Oct 2004

Probabilistic Balancing Of Fault Coverage And Test Cost In Combined Built-In Self-Test/Automated Test Equipment Testing Environment, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

As design and test complexities of SoCs ever intensify, the balanced utilization of combined built-in self-test (BIST) and automated test equipment (ATE) testing becomes desirable to meet the required minimum-fault-coverage while maintaining an acceptable cost overhead. The cost associated with combined BIST/ATE testing of such systems mainly consists of 1) the cost induced by the BIST area overhead and 2) the cost induced by the overall testing time. In general, BIST is significantly faster than ATE, while it can provide only limited fault-coverage, and driving higher fault-coverage from BIST means additional area cost overhead. On the other hand, higher fault-coverage …


Multi-Class Cancer Classification By Semi-Supervised Ellipsoid Artmap With Gene Expression Data, Rui Xu, Donald C. Wunsch, Georgios C. Anagnostopoulos Sep 2004

Multi-Class Cancer Classification By Semi-Supervised Ellipsoid Artmap With Gene Expression Data, Rui Xu, Donald C. Wunsch, Georgios C. Anagnostopoulos

Electrical and Computer Engineering Faculty Research & Creative Works

To accurately identify the site of origin of a tumor is crucial to cancer diagnosis and treatment. With the emergence of DNA microarray technologies, constructing gene expression profiles for different cancer types has already become a promising means for cancer classification. In addition to binary classification, the discrimination of multiple tumor types is also important semi-supervised ellipsoid ARTMAP (ssEAM) is a novel neural network architecture rooted in adaptive resonance theory suitable for classification tasks. ssEAM can achieve fast, stable and finite learning and create hyper-ellipsoidal clusters inducing complex nonlinear decision boundaries. Here, we demonstrate the capability of ssEAM to discriminate …


Low-Input-Voltage, Low-Power Boost Converter Design Issues, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman Sep 2004

Low-Input-Voltage, Low-Power Boost Converter Design Issues, Jonathan W. Kimball, Theresa L. Flowers, Patrick L. Chapman

Electrical and Computer Engineering Faculty Research & Creative Works

Issues associated with boost converter design and performance are investigated when a low input voltage is used. Low-input-voltage sources include single fuel cells, single solar cells, and thermoelectric devices. The primary context is interfacing single micro fuel cells to portable electronic loads, such as mobile phones. Efficiency and circuit startup are the two most difficult issues for a low-cost design. It is shown in theory and experiment that the boost converter has a voltage collapse point. A simple startup technique is proposed that is appropriate for some applications.


Electromagnetic Interference Of System On Package, Toshio Sudo, Hideki Sasaki, Norio Masuda, James L. Drewniak Aug 2004

Electromagnetic Interference Of System On Package, Toshio Sudo, Hideki Sasaki, Norio Masuda, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic interference (EMI) issues are expected to be crucial for next-generation system-on-package (SOP) integrated high-performance digital LSIs and for radio frequency (RF) and analog circuits. Ordinarily in SOPs, high-performance digital LSIs are sources of EMI, while RF and analog circuits are affected by EMI (victims). This paper describes the following aspects of EMI in SOPs: 1) die/package-level EMI; 2) substrate-level EMI; 3) electromagnetic modeling and simulation; and 4) near electromagnetic field measurement. First, LSI designs are discussed with regard to radiated emission. The signal-return path loop and switching current in the power/ground line are inherent sources of EMI. The EMI …


Effects Of Open Stubs Associated With Plated Through-Hole Vias In Backpanel Designs, Shaowei Deng, Jingkun Mao, Todd H. Hubing, James L. Drewniak, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, Chen Wang Aug 2004

Effects Of Open Stubs Associated With Plated Through-Hole Vias In Backpanel Designs, Shaowei Deng, Jingkun Mao, Todd H. Hubing, James L. Drewniak, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander, Chen Wang

Electrical and Computer Engineering Faculty Research & Creative Works

Plated through-hole (PTH) vias are commonly used in printed circuit boards. They usually leave open stubs if the signal(s) does not transition the entire depth of the board. These open stubs can have a negative impact on signal transmission. This summary reports the investigation of the impact of the open via stubs in a typical backpanel design.


Representation Of Permittivity For Multiphase Dielectric Mixtures In Fdtd Modeling, Marina Koledintseva, J. Wu, H. Zhang, James L. Drewniak, Konstantin Rozanov Aug 2004

Representation Of Permittivity For Multiphase Dielectric Mixtures In Fdtd Modeling, Marina Koledintseva, J. Wu, H. Zhang, James L. Drewniak, Konstantin Rozanov

Electrical and Computer Engineering Faculty Research & Creative Works

A simple method of approximating frequency characteristics of composites in a form convenient for time-domain numerical modeling is proposed. The frequency characteristics can be obtained from experiment or calculations based on the Maxwell Garnett mixing formalism. The resultant frequency characteristic might be of a complex shape corresponding to a combination of a number of absorption peaks. The approximation is made by a series of Debye-like terms using a genetic algorithm (GA). This leads to the necessity of taking a number of terms in the approximating series. Every term corresponds to its pole, i.e., the frequency where the maximum loss occurs. …


Static And Quasi-Dynamic Load Balancing In Parallel Fdtd Codes For Signal Integrity, Power Integrity, And Packaging Applications, Sarah A. Seguin, Michael A. Cracraft, James L. Drewniak Aug 2004

Static And Quasi-Dynamic Load Balancing In Parallel Fdtd Codes For Signal Integrity, Power Integrity, And Packaging Applications, Sarah A. Seguin, Michael A. Cracraft, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

The Finite-Difference Time-Domain (FDTD) method is a robust technique for calculating electromagnetic fields, but practical problems, involving complex or large geometries, can require a long time to calculate on any one single-processor computer. One computer with many processors or many single-processor computers can reduce the computation time. However, some FDTD cell types, e.g., PML cells, require more computation time than others. Thus, the size and shape of the individual process allocations can significantly influence the computation time. This paper addresses these load balancing issues with static and quasi-dynamic approaches. The Message-Passing Interface (MPI) library is applied to a three-dimensional (3D) …


Validation Of Equivalent Circuits Extracted From S-Parameter Data For Eye-Pattern Evaluation, Giuseppe Selli, Mauro Lai, Shaofeng Luan, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Giulio Antonini, Antonio Orlandi, Bruce Archambeault, Samuel R. Connor Aug 2004

Validation Of Equivalent Circuits Extracted From S-Parameter Data For Eye-Pattern Evaluation, Giuseppe Selli, Mauro Lai, Shaofeng Luan, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Giulio Antonini, Antonio Orlandi, Bruce Archambeault, Samuel R. Connor

Electrical and Computer Engineering Faculty Research & Creative Works

S-parameter circuit model extraction is usually characterized by a trade off between accuracy and complexity. Trading one feature for another may or may not affect the goodness of the reconstructed S-parameter data, which are obtained from frequency domain simulations of the models extracted. However, the ultimate test for the validity of these equivalent circuit representations should be left to eye-diagram simulations, which provide useful insights, from an SI point of view, about the degradation of the signal, as it travels through the system. Physics based simplication procedures can be used to tune the models and achieve less complexity, whereas the …


A Circuit Approach To Model Narrow Slot Structures In A Power Bus, Lin Zhang, Ray Alexander, Richard E. Dubroff, James L. Drewniak, James L. Knighten, Norman W. Smith, Bruce Archambeault, Samuel R. Connor, Jun Fan Aug 2004

A Circuit Approach To Model Narrow Slot Structures In A Power Bus, Lin Zhang, Ray Alexander, Richard E. Dubroff, James L. Drewniak, James L. Knighten, Norman W. Smith, Bruce Archambeault, Samuel R. Connor, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

A coupled transmission line model for narrow slot structures in DC power planes is proposed. This approach, combined with SPICE-based cavity models and a segmentation method, provides an easy and fast way to model relatively complex structures of power planes with narrow slots often used for isolation purposes. This approach is used to achieve isolation using gapping. The cavity model formulations for rectangular and isosceles right triangular segments are reviewed. The rationale of modeling the narrow slot as a three-conductor transmission line is described. The modeling results are shown and compared with the output of a full wave simulation tool, …


A Cn-Fdtd Scheme And Its Application To Vlsi Interconnects/Substrate Modeling, Rui Qiang, Dagang Wu, Ji Chen, Chen Wang, James L. Drewniak Aug 2004

A Cn-Fdtd Scheme And Its Application To Vlsi Interconnects/Substrate Modeling, Rui Qiang, Dagang Wu, Ji Chen, Chen Wang, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a two-dimensional (2D) Crank-Nicholason (CN) finite difference time domain (FDTD) method is proposed for VLSI interconnect/substrate characterization. Through rigorous truncation and dispersion error analyses, a guideline on using this technique is presented. Several iterative solvers are investigated to accelerate the solution of the CN-FDTD scheme. Numerical examples are given to demonstrate the accuracy and the efficiency of the proposed algorithm.


A Time Domain Approach To Estimate Current Draw From Smt Decoupling Capacitors, Lin Zhang, Bruce Archambeault, Samuel Conner, James L. Knighten, Jun Fan, Norman W. Smith, Ray Alexander, Richard E. Dubroff, James L. Drewniak Aug 2004

A Time Domain Approach To Estimate Current Draw From Smt Decoupling Capacitors, Lin Zhang, Bruce Archambeault, Samuel Conner, James L. Knighten, Jun Fan, Norman W. Smith, Ray Alexander, Richard E. Dubroff, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A time domain approach to investigate and predict impedances and scattering parameters of a DC power bus is proposed. This approach is based on a cavity model and is achieved using a circuit simulation tool - SPICE. A SPICE-based circuit model for triangular power plane segments is described, verified and applied to simulate both the frequency and time domain characteristics of an irregularly shaped two-layer PCB board. Furthermore, the current draw from a surface mount technology (SMT) decoupling capacitor is simulated and estimated using this approach. Near-field electromagnetic loop probes are used to validate the current estimation qualitatively. Additionally the …


Comparison Of Water And Saltwater Movement In Mortar Based On A Semiempirical Electromagnetic Model, Shanup Peer, R. Zoughi Aug 2004

Comparison Of Water And Saltwater Movement In Mortar Based On A Semiempirical Electromagnetic Model, Shanup Peer, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The presence of chloride ions in steel-reinforced structures leads to the corrosion of the reinforcement thus compromising the integrity and strength of the structure. Thus, it is of great interest to nondestructively detect and evaluate free chloride content in concrete. To this end, an investigation was initiated where two mortar cubes were soaked in distilled water and saltwater solutions, respectively. Their temporal microwave reflection properties were measured using open-ended rectangular waveguides on a daily basis for three cycles, each lasting 35 days. Subsequently, a semiempirical electromagnetic model was developed to simulate the reflection properties of the cubes. The outcome of …


Digital Scr Control Box For Educational Laboratory, Zakdy Sorchini, Jonathan W. Kimball, Philip T. Krein Aug 2004

Digital Scr Control Box For Educational Laboratory, Zakdy Sorchini, Jonathan W. Kimball, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

A "blue box" has been designed to introduce the silicone controlled rectifier (SCR) to power electronics students. SCRs are useful in many real-world applications, and are conceptually important in a student's understanding of power converters. The box is highly flexible in application, and its internal design is simple enough to explain to students. Experiments are shown, both of the type commonly used in the laboratory and of the type used for demonstrations. The box has also been designed to be suitable for research purposes and line voltage applications.


Expert System Algorithms For Identifying Radiated Emission Problems In Printed Circuit Boards, Hwan-Woo Shim, Todd H. Hubing, Thomas Van Doren, Richard E. Dubroff, James L. Drewniak, David Pommerenke, R. Kaires Aug 2004

Expert System Algorithms For Identifying Radiated Emission Problems In Printed Circuit Boards, Hwan-Woo Shim, Todd H. Hubing, Thomas Van Doren, Richard E. Dubroff, James L. Drewniak, David Pommerenke, R. Kaires

Electrical and Computer Engineering Faculty Research & Creative Works

Radiated emission algorithms for a printed circuit board EMC expert system are described. The expert system mimics the thinking processes that human EMC engineers would use to analyze circuit boards and make design recommendations. Working with limited information about the enclosure, cables or the exact nature of the signals, the expert system evaluates different structures on the printed circuit board looking for potentially strong radiated emission sources. Results obtained from the analysis of a sample printed circuit board are provided to demonstrate how the expert system quickly identifies problems that would otherwise be difficult to locate.


Extracting R, L, G, C Parameters Of Dispersive Planar Transmission Lines From Measured S-Parameters Using A Genetic Algorithm, Jianmin Zhang, Marina Koledintseva, James L. Drewniak, Giulio Antonini, Antonio Orlandi, Konstantin Rozanov Aug 2004

Extracting R, L, G, C Parameters Of Dispersive Planar Transmission Lines From Measured S-Parameters Using A Genetic Algorithm, Jianmin Zhang, Marina Koledintseva, James L. Drewniak, Giulio Antonini, Antonio Orlandi, Konstantin Rozanov

Electrical and Computer Engineering Faculty Research & Creative Works

Signal integrity (SI) analysis of printed circuit boards for high-speed digital design requires information on the perunit-length R, L, G, C parameters of the transmission lines. However, these are not always available when the property of the dielectric medium used in the board is unknown. A method to extract R, L, G, and C parameters from parallel-plate and strip transmission line geometries is proposed. It is based on measured scattering parameters and analytical modeling. A genetic algorithm (GA) is used to optimize the extraction by minimizing the frequency domain discrepancy between an objective function, which is the measured scattering matrix …


Extraction Of A Spice Via Model From Full-Wave Modeling For Differential Signaling, Shaofeng Luan, Giuseppe Selli, James L. Drewniak, Andrea De Luca, Giulio Antonini, Antonio Orlandi, Antonio Ciccomancini Scogna, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander Aug 2004

Extraction Of A Spice Via Model From Full-Wave Modeling For Differential Signaling, Shaofeng Luan, Giuseppe Selli, James L. Drewniak, Andrea De Luca, Giulio Antonini, Antonio Orlandi, Antonio Ciccomancini Scogna, Jun Fan, James L. Knighten, Norman W. Smith, Ray Alexander

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a procedure for building SPICE models for via transitions in differential signaling. The method of extracting parameters of SPICE models from a full-wave simulation tool is demonstrated. Then the validity of the SPICE models is studied by comparing the solution from the SPICE models with that from the full-wave simulation.