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Power Research at NDSU

by Dr. Joydeep Mitra

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Power and energy systems engineering is the oldest field in electrical engineering. It also comprises one of the biggest industries in any economy. In the United States, the power industry generates over 3 million GWh of energy and over 200 billion dollars of revenue, annually. Over the last century, significant technological progress in the field has established the North American grid as a robust and reliable system. However, in the last few years, legislative, environmental and other forces have caused engineers, economists, lawyers and various activists to take a closer look at the system, and to challenge the established philosophies of energy generation and system operation. This activity has spurred a significant amount of research activity in field.

At NDSU, the power and energy systems research is involved in this action. With six faculty members participating, it is presently the largest, most active and well-funded contiguous research group in the ECE Department. Current research projects cover practically all major areas in the field, and are both theoretical and experimental in nature. In this presentation, we will talk about the various projects and the exciting future of the power and energy systems research program at NDSU.

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Sensor Systems for In-situ Biological Monitoring

by Dr. Joel Jorgenson

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

A proposal for an in-situ biological monitoring system discusses a widespread proliferation of sensor systems designed to monitor biological conditions for agricultural and wetland landscapes. The system of sensors can assist in curbing crop diseases, provide early warnings of wild fires, and improve the capabilities of precision agriculture. The development of the sensor system is based on collaborative efforts from researchers in Soil Science, Chemistry, and Electrical and Computer Engineering. Dr. Joel Jorgenson will present the framework of the proposal, give details of the capabilities, and indicate the road map for future sensor systems.

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Blue Skies and Brainstorms

by Dr. Mark Schroeder

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Dr. Schroeder will be discussing previous and ongoing efforts to improve the state of the ECE department. Last semester, he and doctoral fellow Jeff Wandler created and led the Blue-Sky Group. The group's objectives were to Blue-Sky (to express unrealistic or impractical views) or brainstorm about ways to improve the student, staff, and faculty experience in the department. The presentation will begin with a brief summary of last semester's accomplishments and will be followed by each graduate student introducing him/herself and sharing a Blue-Sky idea of his/her own (come prepared!). Perhaps the faculty will even be queried for a Blue-Sky idea! The remaining time will be used for open-ended comments and discussions about the proposed ideas.

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Fast Algorithms for Designing Multirate Cascade Filters

by Dr. Dave Farden

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

The design of a multirate cascade of discrete-time filters using a FWLS (frequency-weighted least-squares) approach is considered. The design strategy enables one to compensate at each stage for errors introduced by preceding stages in the cascade. As a result, very simple filters can be designed for the stages operating at the higher sampling rates.

A cascade FIR example is presented demonstrating how highly efficient decimators requiring large decimation rates can be designed. The example design yields a cascaded integrator comb (CIC) filter for the first stage. The design strategy applies to the design of interpolators and more arbitrary sample rate converters as well. Design of IIR cascade sections is also addressed.

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Monte Carlo Simulation as a Research Tool

by Shashi Patra and Julan Feng

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Numerical methods known as Monte Carlo methods can be loosely described as statistical simulation methods. These methods have been used for centuries, but only in the past several decades has the technique gained the status of a full-fledged numerical method capable of addressing the most complex applications. These are widely used in fields as diverse as nuclear reactor design, quantum chromodynamics, traffic flow, econometrics, and VLSI design.

We have found that Monte Carlo simulation is a very 13 August, 2008 12:17 PM troducing this concept and describing simple approaches and examples. Both graduate students and faculty will find this introductory material potentially useful to their research areas.

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Energy Efficient Transformers

by Larry Quamme
Powersmiths

Topics covered:

1. HARMONICS MITIGATING ENERGY EFFICIENT TRANSFORMERS
   • Harmonic(s) overview (i.e. origination, harmonics problems, solutions, etc.)
   • Transformer standards & comparisons
   • The effect of loads on performance
   • How harmonics affect energy efficiency and system capacity
   • Problems: neutral current, n-g voltage, and distortion
   • IEEE 519-1992 Std. for harmonic distortion within facilities

2. TRANSIENT VOLTAGE SURGE SUPPRESSION
   • Overview of what transients/surges are
   • Effects on equipment
   • Applications

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A Self-Calibrating Digitizer

by Dr. Mark Pavicic

Dakota Technologies, Inc.,
Fargo, ND

Abstract

This technology uses a DSP to control and calibrate high-speed analog circuitry. Incorporating a programmable digital device has a number of expected benefits like increased flexibility and functionality. In addition, a unit is easier to design and less costly to manufacture. However, total development cost depends on total functionality, which is subject to feature creep. Another very important benefit of this approach is that the system will perform better (be more accurate) than one designed using alternative approaches, given the same amount of time, money, and expertise.

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Efficient Real-Time Implementation of Multi-Stage Interpolation/Decimation Filter

by Debashis Banerjee

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

The techniques of real-time sampling rate conversion, and the interpolation and decimation processes have a wide variety of applications in digital signal processing. These applications include communication systems, speech and audio processing systems, antenna systems and radar systems. The reduced quantization noise in analog to digital (ADC) and digital to analog converters (DAC) at high sampling rates motivates the use of interpolation and decimation techniques to generate high-quality signals. The use of multi-stage form, proper utilization of the polyphase structure and the technique of optimum use of the digital signal processor memory can be applied to develop an efficient interpolation and decimation filtering process.

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and Data Acquisition

by Bob McCarty

National Instruments

Abstract

This presentation will cover the following:

1. Brief introduction to National Instruments
2. Brief overview of the elements of a data acquisition system
3. Brief overview of hardware options
4. Overview of software options with an emphasis on LabVIEW
5. Demonstration of a LabVIEW-based data acquisition system

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Information Gathering Via Infra-Red Imaging

by Prof. Floyd Patterson

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Correct interpretation of infra-red imagery requires basic physics knowledge of emission, reflection, absorption, and transmission of electromagnetic energy. Forensic science, failure/fault analysis, stealth security systems, and medical diagnostic procedures are seeing increased use of infra-red use.

The presentation will begin with a statement of what the public is told about forensic use followed by a short video of an actual North Dakota Bureau of Criminal Investigation tape on a criminal case. A demonstration tape admitted in court demonstrating possible interpretation of the infra-red was made in an ECE lab and will be shown. A more general discussion of the possible sources of energy to the imaging camera will complete the presentation.

A very high quality, research grade camera will be shown if available. Since this camera requires time to cool down, is noisy in the process, and requires a separate monitor for audience viewing, it will not be operating.

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Design of a Monolithic, Low-Power, Low-Area Microcontroller Clock Generation System

by Tristan Simetkosky

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Thanks to recent advances in semiconductor fabrication, increasingly complex circuits can be integrated into a single die. This increased level of integration has many benefits. Placing more functionality onto a single chip reduces the system part count, which reduces assembly costs, which reduces the overall system cost. Another benefit is portability. However, many portable systems are battery powered, which means that power consumption must be minimized.

This research discusses the design of a microcontroller clock generation system which attempts to increase the level of integration and minimize power consumption. Increasing the level of integration is accomplished by including all clock generation circuity on-chip. While the clock generation system is designed to be low-power itself, the most significant power savings will arise from the ability to dynamically adjust the clock frequency. This is unique in that many devices have a sleep or shutdown mode, but it is not common to have several low power modes in which normal operations are still performed.

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Nonlinear Oscillations - A Gentle Introduction

by Dr. Rajesh Kavasseri

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Several physical, engineering, and biological systems are often modeled by nonlinear equations which represent the system dynamics. In this talk (which is meant to be more of a primer), the speaker will introduce some of the fundamental tools and techniques involved in the analysis of such systems. Specifically, the talk will deal with the analysis of primary, subharmonic, ultraharmonic, and ultrasubharmonic resonances in nonlinear systems.

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Design of a Monolithic, Low-Power, Low-Area Microcontroller Clock Generation System

by Tristan Simetkosky

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

Thanks to recent advances in semiconductor fabrication, increasingly complex circuits can be integrated into a single die. This increased level of integration has many benefits. Placing more functionality onto a single chip reduces the system part count, which reduces assembly costs, which reduces the overall system cost. Another benefit is portability. However, many portable systems are battery powered, which means that power consumption must be minimized.

This talk describes the design of a microcontroller clock generation system which attempts to increase the level of integration and minimize power consumption. Increasing the level of integration is accomplished by including all clock generation circuity on-chip. While the clock generation system is designed to be low-power itself, the most significant power savings will arise from the ability to dynamically adjust the clock frequency. This is unique in that many devices have a sleep or shutdown mode, but it is not common to have several low power modes in which normal operations are still performed.

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Inductive Links with Integrated Receiving Coils for MEMS and Implantable Applications

by Dr. Jie Wu

Dept. of Electrical Engineering,
University of Notre Dame
Notre Dame, Indiana

Abstract

Microsystems, consisting of microelectromechanical systems (MEMS) actuators, sensors and control circuits, etc., can bring about revolutionary advancement in many fields, especially for implantable, autonomous applications. When freeing such microsystem chips from wire tethering, one major obstacle is the powering needs of MEMS devices, especially microactuators. Here we demonstrate that inductive links with integrated receiving coils can provide sufficient voltage or power to many MEMS devices. An inlaid electroplating procedure was developed to reduce large internal resistance of integrated receiving coils. Enhanced output is obtained for inductive links with micromachined microcoils.

Another application involves inductive transmission of low frequency waveforms. Some medical conditions, such as tremor, benefit from such a technique for electrical stimulation. This is challenging due to imperfect coupling and limited coil inductance. Amplitude modulation is adopted to circumvent this difficulty, and electroplated coils also provide better performance.

Link resonance is observed and used to selectively transmit signals to multiple receiving coils from a frequency-multiplexing input. A dual-coil fabrication process with electroplated through-wafer vias is developed for future integration of microcoils with semiconductor electronics. Combining dual coils with discrete demodulation and switching transistors, arbitrary biphasic waveforms are generated across a resistor representing body tissue. The above results offer possibilities to replace pulse generators with an external unit in coordination with implanted receiving coils and circuit components.

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DSP-Based Projects on Spectroscopy and Digitizers

by Adnanul Haq, Henry Von Bank, and Kurt Peterson

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstracts

1. B-Spline Enhanced Time-Spectral Analysis

   Conventional Fourier-based Time-Frequency analysis techniques such as Spectrogram, suffer from time localization and frequency localization problems. This presentation will show how these issues can be mitigated through the judicious use of B-Spline algorithms.

2. DSP-Based EIS Instrument

   Electrochemical Impedance Spectroscopy, or EIS, is a technique used to obtain the impedance of a material to determine its electrochemical properties. This presentation will report progress on the development of a DSP-based EIS instrument, and discuss the requirements and applications of such an instrument.

3. DTI Digitizer Characterization

   Static and dynamic error parameters are used to characterize typical analog-to-digital converters (ADC). However, the analog transient waveform digitizer (ATWD) being used by Dakota Technologies, Inc. (DTI) is not a typical ADC. This presentation will discuss the differences of the DTI ATWD and propose various methods to help characterize the device and deliver improved performance.

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Marching from Microelectronics towards Nanoelectronics

by Dr. Jixin Yu

Beckman Institute for Advanced Science and Technology
Dept. of Electrical and Computer Engineering
University of Illinois at Urbana-Champaign
Urbana, Illinois

Abstract

With the continuous downscaling of microelectronic device sizes (Moore's Law), we are now quickly approaching the nanometer scale electronics region (nanoelectronics). Molecular nanoelectronics, albeit faced with formidable problems, represents a potential avenue for continued progress beyond the physical limits of CMOS. To explore this possibility we are developing methods for creating hybrid systems in which molecular arrays are embedded within a CMOS matrix. This talk will focus on our work using ultrahigh vacuum scanning tunneling microscopy (UHV-STM) as a tool for fabricating molecular arrays and as a characterization tool to explore critical issues associated with continued CMOS scaling.

With UHV-STM we are able to selectively create single Si dangling bonds or dangling bond patterns on the H-passivated Si(100) surface. The strong chemical contrast between dangling bonds and the H-passivated Si surface allows molecules to self-assemble onto the single dangling bond or patterned areas. Several metals and organic molecules (such as CuPc, norbornadiene, C60, and carbon nanotubes) have been deposited and studied. We have investigated the electronic, chemical and mechanical properties of isolated CoPc molecules adsorbed on both Si(100)2x1 and Si(100)2x1:H surfaces with single dangling bonds. Quasi-quantum mechanical modeling was performed on the adsorption configurations to reveal the adsorption kinetics. Different interactions between CoPc and the Si substrates will be in discussed detail, as well as their effects upon the electronic charge distribution and geometric configurations of the adsorbed CoPc molecules.

We also used the UHV-STM to directly characterize the oxide-silicon interface roughness that leads to inversion layer carrier mobility degradation in deep submicron CMOS devices. We demonstrated for the first time that UHV-STM could be used to directly extract the surface roughness parameters from the topography. We measured the corresponding electron and hole mobilities, and compared the results with calculations of the mobilities that are completely constrained by measured parameters. The concurrence between the measurements and calculations indicates that interface roughness scattering accounts for the measured mobility at high electric field. A standard shallow trench isolation process flow has been examined and modified to produce a smoother interface. Initial experiments indicate that we should expect a factor of four mobility improvement in the high field limit with the modified process flow.

Another key issue in current Si technology is the need for nanometer-resolution dopant profiles. Due to the random nature of ion implantation and diffusion, the dopant density in shallow junctions and short channels is subject to stochastic variation, which translates directly into variations in device behaviors. We have demonstrated for the first time that individual dopants in different Si(100) sub-surface layers can be observed by STM, and three dimensional dopant profiles can be extracted with atomic resolution. We were also able to acquire STM topographic images, dI/dV images, and Current Image Tunneling Microscopy (CITS) across lateral p-n junctions of Si devices. Two dimensional carrier profiles were extracted from the CITS data with 1nm resolution.

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Analog and Mixed Signal Test and Fault Diagnosis

by Dong Liu

School of Electrical Engineering & Computer Science
Ohio University
Athens, Ohio

Abstract

Analog and mixed-signal (AMS) test and fault diagnosis plays an essential role in circuit design, device production, and instrumentation maintenance. The benefits include correcting design flaws, reducing time-to-market, increasing manufacture yield, and reducing system cost. Usually, AMS test and fault diagnosis consists of three tasks. The first one is fault detection to check if the CUT is faulty or not, which is usually called test in industry. If the CUT is judged faulty, the second task is fault location to find out where the faulty parameters are inside the faulty circuit. The final task is parameter evaluation to compute how much the faulty parameters are deviated from their nominal values. The difficulties for AMS test and fault diagnosis come from ambiguities, increased complexity, reduced accessibility, lack of effective fault model, increased test cost.

In this presentation, the above problems are explored. A verification method based on ambiguity group locating technique is designed for accurate computing and efficient fault diagnosis. To decrease complexity and increase accessibility, a decomposition technique is implemented to decompose large scale system and calculate voltages of inaccessible nodes. An optimum test nodes selection algorithm will be introduced to find out a local minimum set whose efficient and solution accuracy is the best comparing with other reported algorithms. To locate multiple analog catastrophic faults, an analog stuck fault location approach is designed removing the repetitive simulation required by traditional analog test approaches. One example of mixed-signal system, sampling voltmeter is utilized for model building and analog simulation in order to test and locate its fault mechanism.

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Conservation Laws for Control Systems

by Dr. Rodney Holland

Visiting Professor
Electrical & Computer Engineering
NDSU
Fargo, ND

Abstract

This session is designed as a lecture at the senior undergraduate and first year graduate student level. A common belief among engineers is that a control system can almost always be designed to provide an arbitrary level of performance. However, there are fundamental system characteristics apart from the controller that limit the performance of the control. Curiously, these fundamental requirements were noted in Bode's original 1945 paper, but were generally ignored for the next 45 years. This lecture looks at the sensitivity and complementary sensitivity transfer functions and explains system limitations in terms of those functions with respect to performance and model integrity. Additional requirements are introduced via Bode's integral applied to the sensitivity transfer function to provide a practical means of assessing the feasibility of a control system specification one might receive as part of a project.

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Modeling receivers in optical fiber communications systems

by Ivan T. Lima, Jr.

Electrical & Computer Science and Electrical Engineering
Univ. of Maryland, Baltimore County
Baltimore, MD

Abstract

Accurate modeling of receivers is essential for the design of modern optical fiber communications systems. The performance of these systems depends just as much on the design of the receiver as on the characteristics of the incoming optical signal. In this talk I will describe a new receiver model that relates two of the most widely used measures of performance for optical communications systems: The optical signal-to-noise ratio (OSNR) and the Q-factor. When the optical noise is unpolarized there is a unique relationship between the Q-factor and the OSNR. The major contribution of the new model is to show that if the optical noise is arbitrarily polarized, the relationship between the Q-factor and the OSNR is not unique. By taking the polarization state of the noise into account, we obtained excellent agreement between theory and experiments.

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Transmission and Generation Planning Processes Within the Upper Midwest Region of North America

by Ryan D. Retzlaff

Dept. of Electrical and Computer Engineering,
NDSU
Fargo, ND

Abstract

The North American high voltage transmission system is one of the largest infrastructures in the world. This infrastructure is continually changing and growing to meet societal demands. In order to safely, reliably, and economically meet these demands, it is necessary to maintain an efficient and effective high voltage transmission and generation planning process.

This presentation examines the high voltage transmission and generation planning process utilized in the upper Midwest region of North America.

We will discuss the current state of large transmission governing bodies in the upper Midwest, planning study techniques, system modeling, and system design standards. We also demonstrate the validity of the upper Midwest planning process through the examination of a case study: the Solway Combustion Turbine Transmission Study.

We demonstrate that the high voltage transmission and generation planning process utilized in the upper Midwest region of North America is valid, prudent, and dependable.

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