Engineering Commons^™

Disordered Speech Assessment Using Automatic Methods Based On Quantitative Measures, Lingyun Gu, John G. Harris, Rahul Shrivastav, Christine Sapienza

Electrical and Computer Engineering Faculty Research & Creative Works

Speech quality assessment methods are necessary for evaluating and documenting treatment outcomes of patients suffering from degraded speech due to Parkinson's disease, stroke, or other disease processes. Subjective methods of speech quality assessment are more accurate and more robust than objective methods but are time-consuming and costly. We propose a novel objective measure of speech quality assessment that builds on traditional speech processing techniques such as dynamic time warping (DTW) and the Itakura-Saito (IS) distortion measure. Initial results show that our objective measure correlates well with the more expensive subjective methods. © 2005 Hindawi Publishing Corporation.

Coordination Of Ufls And Ufgc By Application Of D-Smes, Li Zhang, Yilu Liu, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the authors studied the coordination of under frequency load shedding (UFLS) and under frequency governor control (UFGC) by applying the distributed superconducting magnetic energy storage (D-SMES) devices. The active power of D-SMES device is controlled to eliminate the initial rapid frequency drop and allow time for the full action of UFGC to take over. The reactive power of D-SMES is controlled to stabilise the local bus voltage. The research results show that D-SMES devices can damp the quick dropping of system frequency and hold it waiting for the full activation of system spinning reserve. D-SMES can help …

Three-Dimensional Radiative Transfer In An Isotropically Scattering, Plane-Parallel Medium: Generalized X- And Y-Functions, D. W. Mueller, A. L. Crosbie

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The topic of this work is the generalized X- and Y-functions of multidimensional radiative transfer. the physical problem considered is spatially varying, collimated radiation incident on the upper boundary of an isotropically scattering, plane-parallel medium. an integral transform is used to reduce the three-dimensional transport equation to a one-dimensional form, and a modified Ambarzumian's method is used to derive coupled, integro-differential equations for the source functions at the boundaries of the medium. the resulting equations are said to be in double-integral form because the integration is over both angular variables. Numerical results are presented to illustrate the computational characteristics of …

Teaching Nanotechnology By Introducing Crossbar-Based Architecture And Quantum-Dot Cellular Automata, Minsu Choi, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

The end of photolithography as the driver for Moore's law is predicted within seven to twelve years and six different emerging technologies (mostly nanoscale) are expected to replace the current CMOS-based system integration paradigm. As nanotechnology is emerging, (1) there is a strong need for well-educated nanoscale systems engineers by industry, and (2) research and education efforts are also called to overcome numerous nanoscale systems issues. This paper is to propose a way to teach nanotechnology by introducing two emerging technologies: crossbar-based nanoarchitecture and quantum-dot cellular automata.

Liquid Saturation And Gas-Liquid Distribution In Multiphase Monolithic Reactors, Tobias Bauer, Shaibal Roy, Ruediger Lange, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

The Monolith Bed is One of the Promising Catalytic Reactors for a Number of Chemical Gas-Liquid-Solid Processes. in the Present Work, Liquid Saturations for Five Different Monoliths Have Been Investigated Experimentally in a Cold-Flow Unit with a Reactor Diameter of 5.0 Cm. the Influences of Gas and Liquid Flow Rates and of the Direction of Two-Phase Flow on Liquid Saturation Were Examined. the Results Indicate that the Direction of Flow Has No Significant Influence on Liquid Saturation for Proper Gas-Liquid Distribution. the Experimental Results Are in Good Agreement with Predictions of the Drift Flux Model using the Distribution Parameter Proposed …

A Matter Of Priorities: Effects Of Increased Opportunities For Extracurricular And Non-Traditional Learning Experiences On Student Time Management And Attitudes, David Spurlock, Daniel J. Bailey, Susan L. Murray, Andrew S. Ricke

Engineering Management and Systems Engineering Faculty Research & Creative Works

Many schools are emphasizing non-traditional and extracurricular learning experiences for undergraduate engineering students. These include activities such as incorporating servicelearning projects into the classroom, involving students in design competitions (e.g., solar car, formula car races), and promoting involvement in traditional campus organizations. Often this emphasis is in response to changes in ABET requirements, desires of future employers, and needs to improve student retention. What are the effects of emphasizing these sorts of activities on student attitudes and time management decisions? We examine the influences on students' priorities for allocating their time and their perceptions of the relative importance of available …

Hands-On Projects And Exercises To Strengthen Understanding Of Basic Computer Engineering Concepts, Rohit Dua, John E. Seiffertt Iv, Brian Blaha, Kapil Gupta, Venkat Satagopan, R. Joe Stanley, Daryl G. Beetner, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

The Introduction to Computer Engineering course at the University of Missouri-Rolla provides a thorough understanding of basic digital logic analysis and design. The course covers: digital numbering systems, Boolean algebra, function minimization using Karnaugh maps (K-maps), memory elements, and sequential logic design. Students' grades are determined by their performance on homework assignments, quizzes, and in-class examinations. A laboratory course (optional for all but EE and CpE majors) supplements the lecture by providing experiments that include analysis and design using Mentor Graphics and FPGAs. While the laboratory is a very useful supplement to the lecture, almost half the students taking the …

Modeling Controlled Switches And Diodes For Electro-Thermal Simulation, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

Designers of advanced power converters may choose from a variety of switching device models for simulation. Some situations call for simple idealized models, while others require physics-based models. When evaluating thermal system performance, a behavioral model that includes both conduction and switching losses is desired. A set of models has been developed to include both unidirectional devices, such as IGBTs, BJTs, and diodes, and bidirectional devices, such as MOSFETs. Logic and timing elements are used to insert voltage and current sources into the circuit at appropriate times. All losses affect circuit operation, so simulation can accurately predict losses when the …

Power Engineering Laboratory Facilities At The University Of Missouri--Rolla, Keith Corzine, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

One of the significant niche areas at UMR is the area of electric power. For this reason UMR has invested in its power program over the years. The extent of this program ranges from power systems, motor drives, high-frequency effects in electric machines, acoustic noise of electric machines, FACTS device for electric utility applications, and naval propulsion power systems. The various laboratory facilities at UMR which supports these activities have been described in detail in this paper.

Environmental-Based Characterization Of Soc-Based Instrumentation Systems For Stratified Testing, N. J. Park, Koshy M. George, Nohpill Park, Minsu Choi, Yong-Bin Kim, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel environmental-based method for evaluating the good yield rate (GYR) of systems-on-chip (SoC) during fabrication. Testing and yield evaluation at high confidence are two of the most critical issues for the success of SoC as a viable technology. The proposed method relies on different features of fabrication, which are quantified by the so-called Fabrication environmental parameters (EPs). EPs can be highly correlated to the yield, so they are analyzed using statistical methods to improve its accuracy and ultimately direct the test process to an efficient execution. The novel contributions of the proposed method are: 1) to …

Facts/Ess Allocation Research For Damping Bulk Power System Low Frequency Oscillation, Li Zhang, Fei Wang, Yilu Liu, Michael R. Ingram, Steve Eckroad, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

Blue-Box Approach To Power Electronics And Machines Educational Laboratories, Robert S. Balog, Zakdy Sorchini, Jonathan W. Kimball, Patrick L. Chapman, Philip T. Krein, Peter W. Sauer

Electrical and Computer Engineering Faculty Research & Creative Works

Our approach to laboratory education in power electronics and electric machines is presented. The approach centers upon "blue-box" laboratory components, that aid the student in rapid experiment assembly without disguising important aspects of the hardware. Several example experiments are presented. Schematics and construction techniques for the hardware are publicly available.

Control Technique For Series Input-Parallel Output Converter Topologies, Jonathan W. Kimball, Joseph T. Mossoba, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

A series input-parallel output DC-DC converter topology inherently provides output current sharing among the phases, provided the input voltages are forced to share. With conventional output voltage feedback controls, input voltage sharing is unstable. Recent literature work proposes complicated feedback loops to provide stable voltage sharing, at the expense of dynamic performance. In the current work, a simple controller based on the sensorless current mode approach (SCM) stabilizes voltage sharing without compromising system performance. The SCM controllers reject source disturbances, and allow the output voltage to be tightly regulated by additional feedback control. With SCM control in place, a #super-matched# …

Hierarchical Optimal Force-Position-Contour Control Of Machining Processes. Part I. Controller Methodology, Yan Tang, Robert G. Landers, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

There has been a tremendous amount of research in machine tool servomechanism control, contour control, and machining force control; however, to date these technologies have not been tightly integrated. This paper develops a hierarchical optimal control methodology for the simultaneous regulation of servomechanism positions, contour error, and machining forces. The contour error and machining force process reside in the top level of the hierarchy where the goals are to 1) drive the contour error to zero to maximize quality and 2) maintain a constant cutting force to maximize productivity. These goals are systematically propagated to the bottom level, via aggregation …

Nanocomposite Nickel Ceria Cermet With Low Nickel Content For Anode-Supported Sofcs, Piotr Z. Jasinski, Toshio Suzuki, Vladimir Petrovsky, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

Ni-ceria cermet's with 7.5, 11, and 14 vol % of Ni manufactured by a novel method, called net-shape technology, are presented and evaluated. the method is a combination of conventional ceramic sintering and a polymer precursor impregnation technique. Ceria powder with a carbon pore former is sintered, constructing a rigid and stable oxide skeleton, which is next backfilled with Ni polymer precursor. the electrical conductivity of the cermet's as a function of Ni content has been investigated. © 2005 the Electrochemical Society. All rights reserved.

Ac Impedance Measurement Techniques, Keith Corzine, M. Belkhayat, Yakov L. Familiant, Jing Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Naval ship as well as aerospace power systems are incorporating a greater degree of power electronic switching sources and loads. Although these power electronics based components provide exceptional performance, they are prone to instability due to their high efficiency and constant power characteristics which lead to negative impedance. When designing these systems, integrators must consider the impedance versus frequency at a system interface (which designates source and load). Stability criterions have been developed in terms of source and load impedance for both dc and ac systems and it is often helpful to have techniques for impedance measurement. For dc systems, …

Aisi Standard For Cold-Formed Steel Framing – Truss Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary. With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is …

Standard For Cold-Formed Steel Framing - Truss Design, 2004 Edition, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

The material contained herein has been developed by the American Iron and Steel Institute Committee on Framing Standards. The Committee has made a diligent effort to present accurate, reliable, and useful information on cold-formed steel framing design and installation. The Committee acknowledges and is grateful for the contributions of the numerous researchers, engineers, and others who have contributed to the body of knowledge on the subject. Specific references are included in the Commentary.

With anticipated improvements in understanding of the behavior of cold-formed steel framing and the continuing development of new technology, this material may eventually become dated. It is …

Distributed Control Of Hybrid Motor Drives, Shuai Lu, Keith Corzine, T. H. Fikse

Electrical and Computer Engineering Faculty Research & Creative Works

No abstract provided.

The Wettability Of Titanium Diboride By Molten Aluminum Drops, D. A. Weirauch, W. J. Krafick, G. Ackart, P. D. Ownby

Materials Science and Engineering Faculty Research & Creative Works

Titanium diboride is widely accepted to be completely wet by liquid aluminum, yet few published wetting studies demonstrate this behavior, and reported contact angles vary widely. Sessile drop substrates from four different sources were selected and their microstructures and chemistries characterized. the results of sessile drop experiments using four techniques to modify oxide film behavior were compared. the Al-TiB2 interfaces were examined in metallographic sections or after chemical removal of the Al drop. Al wets a material containing 5.5 wt% Ni in vacuum experiments before the hold temperature of 1025°C is reached. the other TiB2 substrates are completely wet by …

Coupling Between Differential Signals And The Dc Power-Bus In Multilayer Pcbs, Chen Wang, Marco Leone, James L. Drewniak, Antonio Orlandi

Electrical and Computer Engineering Faculty Research & Creative Works

Differential and common-mode transfer impedances are proposed herein to analyze noise coupled to (from) the dc power-bus from (to) via transitions in differential signals. Expressions for the two transfer impedances in terms of conventional single-ended transfer impedances are derived and verified through measurements, full-wave finite-difference time-domain (FDTD) simulations and an analytical cavity model. Some properties of the differential and common-mode transfer impedances are investigated to facilitate engineering design. The impact of signal current imbalances on power-bus noise and the benefit of differential signals as compared to single-ended signals are quantified.

Modern Laboratory-Based Education For Power Electronics And Electric Machines, Robert S. Balog, Zakdy Sorchini, Jonathan W. Kimball, Patrick L. Chapman, Philip T. Krein

Electrical and Computer Engineering Faculty Research & Creative Works

The study of modern energy conversion draws upon a broad range of knowledge and often requires a fair amount of experience. This suggests that laboratory instruction should be an integral component of a power electronics and electric machines curriculum. However, before a single watt can be processed in a realistic way, the student must understand not only the operation of conversion systems but also more advanced concepts such as control theory, speed and position sensing, switching signal generation, gate drive isolation, circuit layout, and other critical issues. Our approach is to use a blue-box module where these details are pre-built …

Survey Of Clustering Algorithms, Rui Xu, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Data analysis plays an indispensable role for understanding various phenomena. Cluster analysis, primitive exploration with little or no prior knowledge, consists of research developed across a wide variety of communities. The diversity, on one hand, equips us with many tools. On the other hand, the profusion of options causes confusion. We survey clustering algorithms for data sets appearing in statistics, computer science, and machine learning, and illustrate their applications in some benchmark data sets, the traveling salesman problem, and bioinformatics, a new field attracting intensive efforts. Several tightly related topics, proximity measure, and cluster validation, are also discussed.

Spare Line Borrowing Technique For Distributed Memory Cores In Soc, B. Jang, Minsu Choi, Nohpill Park, Vincenzo Piuri, Fabrizio Lombardi, Yong-Bin Kim

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a new architecture of distributed embedded memory cores for SoC is proposed and an effective memory repair method by using the proposed Spare Line Borrowing (software-driven reconfiguration) technique is investigated. It is known that faulty cells in memory core show spatial locality, also known as fault clustering. This physical phenomenon tends to occur more often as deep submicron technology advances due to defects that span multiple circuit elements and sophisticated circuit design. The combination of new architecture & repair method proposed in this paper ensures fault tolerance enhancement in SoC, especially in case of fault clustering. This …

Wide-Band Lorentzian Media In The Fdtd Algorithm, Marina Koledintseva, James L. Drewniak, David Pommerenke, Giulio Antonini, Antonio Orlandi, Konstantin Rozanov

Electrical and Computer Engineering Faculty Research & Creative Works

This paper considers the case of a wide-band Lorentzian (WBL) algorithm in the finite-difference time-domain (FDTD) modeling of dispersive media. It is shown herein that the WBL model is a physically meaningful and practically useful case of the frequency behavior of materials along with the Debye and narrow-band Lorentzian (NBL). The recursive convolution algorithms for the finite-difference time-domain technique for NBL and WBL models differ. The Debye model, which is suitable for comparatively low-frequency dispersive materials, may not have sufficient number of parameters for describing the wide-band material, especially if this material exhibits pronounced absorption at higher frequencies. It is …

High-Temperature Monitoring Of Refractory Wall Recession Using Frequency-Modulated Continuous-Wave (Fm-Cw) Radar Techniques, Bivin Varghese, C. Deconick, G. Cartee, M. Velez, Robert E. Moore, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Furnaces are among the most crucial components in the glass and metallurgical industry. Nowadays, furnaces are being operated at higher temperatures and for longer periods of time thus increasing the rate of wear on the furnace refractory lining. Consequently, there is a great need for a nondestructive tool that can accurately measure refractory wall thickness at high temperatures. In this paper the utility of a frequency-modulated continuous-wave (FM-CW) radar is investigated for this purpose.

Microwave Reflectometry As A Novel Diagnostic Method For Detection Of Skin Cancers, Kundan Chand, Pratik Mehta, Daryl G. Beetner, R. Zoughi, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

More than one million people are diagnosed with skin cancer each year in the United States and more than ten thousand people die from the disease. Currently, there are some methods for early detection of skin cancers, like visual inspection, but improvements are needed. This paper presents a method involving microwave reflectometry as a diagnostic tool for detection of skin cancers. The results of measurements and simulations for normal and wet skin have been shown to distinguish among skin samples with different properties. Microwave measurements from lesions have also been presented which are used to distinguish between cancerous and benign …

Millimeter Wave Detection Of Localized Anomalies In The Space Shuttle External Fuel Tank Insulating Foam And Acreage Heat Tiles, Sergey Kharkovsky, R. Zoughi, J. T. Case, F. L. Hepburn

Electrical and Computer Engineering Faculty Research & Creative Works

Undesired manufactured or in-service produced anomalies in the form of voids in the SOFI and unbonds in the heat tiles can significantly reduce their designed effectiveness. Additionally, unbonds in the heat tiles may cause their complete separation from the fuselage exposing it to extreme heat. Millimeter wave NDT methods are viable candidate for life-cycle inspection of the SOFI and the acreage heat tiles of the Space Shuttle fleet. The results of these investigations described in this paper clearly showed the utility of these methods for detecting localized anomalies in thick SOFI and acreage heat tiles. These methods are fast and …

Dielectric Material Characterization By Complex Ratio Of Embedded Modulated Scatterer Technique States, Gabriel S. Freiburger, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The embedded modulated scatterer technique (MST) is an innovative tool which can be used for microwave dielectric characterization of infrastructure and composite structures. By impinging a microwave signal on a loaded thin dipole antenna embedded in a material whose dielectric properties are sought, the resulting refelction data can be used to inversely solve for the dielectric properties of interest. Previous investigations utilized reflection information from a single loaded dipole and required known system parameters, such as radiator polarization vs. dipole alignment and relative distance between radiator and probe, to solve for the sought-for dielectric properties. This paper explores a unique …

Advanced Control Of Cascaded Multilevel Drives Based On P-Q Theory, Shuai Lu, Keith Corzine, T. H. Fikse

Electrical and Computer Engineering Faculty Research & Creative Works

In recent years, there has been significant development on the cascaded multilevel inverter wherein the series connection is accomplished by splitting the neutral point of the load and driving both ends with power converters. This splits the power between a "bulk" inverter supplying higher-voltage low-frequency power and a "conditioning" inverter supplying low-voltage high-frequency power and leads to exceptional power quality which is necessary in applications such as naval propulsion that require extremely low THD. This paper reports the development of a new control method for the cascaded multi-level inverter. The primary advantage of this new control is that the bulk …