Engineering Commons^™

Digital Design For A Sweeping Langmuir Probe Board, Omar Morales

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In-situ probing of the Earth's upper atmosphere has greatly contributed to the understanding of the ionosphere's variations and structures. The purpose of this research project has been to develop the digital component of a Swept Langmuir Probe that will be used on a sounding rocket to be launched through the equatorial ionosphere. The probe will make measurements of the plasma density and temperature in the ionosphere.

The digital component uses an FPGA to perform three main functions in parallel which are generating a sweeping voltage on the probe, sampling data channels, and communicating measured data to external devices. The FPGA …

Calibration Of Plasma Impedance Probe On The Floating Potential Measurement Unit, Krishna Kishore Kurra

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Charging of the International Space Station (ISS) is identified as a potential space hazard for astronauts. Floating potential measurement unit (FMPU) was developed to address this issue. This project is aimed at developing a procedure for the calibration of Plasma Impedance Probe, one of the four probes housed by FPMU. Non-linear curve fits are used to find the calibration coefficients and the equations are symbolically solved to obtain the load magnitude and phase from the pulse code modulated (PCM) data. There is a brief discussion of various methods tried during this process. The results are compared with the actual test …

Susceptibility Characterization Of A Cavity With An Aperture By Using Slowly Rotating Em Fields: Fdtd Analysis And Measurements, Kimitoshi Murano, Takeshi Sanpei, Fengchao Xiao, Chen Wang, Yoshio Kami, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes the evaluation of the susceptibility of a cavity with an aperture using the finite-difference time-domain (FDTD) method and experimentally. To reduce the computing time, the FDTD method is used for the radiation from the cavity and the susceptibility is obtained by using the reciprocity theorem. The cavity used here is modeled after a full-tower desktop enclosure with a 3.5-in bay. The susceptibility characteristics are evaluated by measuring outputs of a monopole antenna and transmission lines installed in the cavity. The susceptibility characteristics, using a three-dimensional (3-D) map, are studied from the computed and the measured results by …

A System For Monitoring Pressures And Spinal Curvature In Spinally Injured People Immobilised On A Spinal Raft, Ruairí De Fréin, Eoin Flinn, Ted Burke

Articles

We present a system designed to study the pressure at various ‘hot spots’ on the back of the body and the deformation of the spine experienced by a patient when strapped to a spinal board, and the potential alleviation of both by the addition of an inflatable “spinal raft” (or other similar device). In measuring pressure we devised a system of air-filled sacks interfaced with a PC. Each sack, placed under a particular key point on the body, is inflated until its faces just begin to separate and a switch thereby opens. The pressure reading is then captured and displayed …

High Confidence Testing For Instrumentation System-On-Chip With Unknown-Good-Yield, N. J. Park, Bin Jin, Koshy M. George, Nohpill Park, Minsu Choi

Electrical and Computer Engineering Faculty Research & Creative Works

SoCs are in general built with embedded IP cores, each of which is procured from different IP providers with no prior information on known-good-yield (KGY). In practice, partial testing is a practical choice for assuring the yield of the product under the stringent time-to-market requirements. Therefore, a proper sampling technique is a key to high confidence testing and cost effectiveness. Based on previous research, this paper proposes a novel statistical testing technique for increasingly hybrid integrated systems fabricated on a single silicon die with no a-priori empirical yield data. This problem is referred to as the unknown-good-yield (UKGY) problem. The …

Application Of Bi-State Magnetic Material To Automotive Offset-Coupled Ipm Starter/Alternator Machine, Ayman M. El-Refaie, Russell Manzke, Thomas M. Jahns

Electrical and Computer Engineering Faculty Research and Publications

This paper investigates a new approach to designing high-speed interior permanent-magnet (IPM) synchronous machines using a bi-state soft magnetic material. The bi-state material can have its normally high magnetic permeability permanently reduced in localized regions to that of air by means of heat treatment. This new work significantly expands a previous investigation by considering offset-coupled IPM machines that make it possible to significantly increase the rotor speed while retaining all of the other specifications of the 6-kW starter/alternator application. Lumped-parameter models, Monte Carlo optimization, and both electromagnetic and structural finite-element analysis are used to develop new offset-coupled IPM machine designs …

Comparison Of Near-Field Millimeter Wave Probes For Detecting Corrosion Pit Under Paint, Mohammad Tayeb Ahmad Ghasr, Sergey Kharkovsky, R. Zoughi, Russell A. Austin

Electrical and Computer Engineering Faculty Research & Creative Works

Corrosion pitting defection is a critical issue in the maintenance of aircraft. Near-field microwave nondestructive techniques have been successfully used for defection of corrosion under paint. In this paper a comparison between several different millimeter wave probes is made for the detection and evaluation of corrosion precursor pitting under paint at Ka-band and V-band. Since the pittings investigated here are very small in size, spatial resolution and sensitivity of the probes are critical issues. If is shown that modified open-ended rectangular probes namely, tapered waveguide and dielectric slab-loaded waveguide probes provide high resolution and sensitivity for the detection and evaluation …

A Web-Shareable Real-World Imaging Problem For Enhancing An Image-Processing Curriculum, R. Joe Stanley, Steve Eugene Watkins, Anand Gopal, Randy Hays Moss

Electrical and Computer Engineering Faculty Research & Creative Works

A real-world laboratory exercise is presented for image processing and related curricula. The exercise is a traffic-monitoring problem in which a truck must be tracked as it moves across a bridge and its velocity measured. Sequential images are taken from a dedicated Web camera that views the Smart Composite Bridge on the University of Missouri-Rolla campus. The prototype bridge is a field laboratory for several interdisciplinary courses, including a Machine Vision elective. The Machine Vision image-processing elective uses the traffic-monitoring exercise to give students experience with processing complex images, tracking image markers, and applying theoretical orthographic concepts. The laboratory exercise …

Cost-Driven Optimization Of Fault Coverage In Combined Built-In Self-Test/Automated Test Equipment Testing, Shanrui Zhang, Minsu Choi, Nohpill Park, Fabrizio Lombardi

Electrical and Computer Engineering Faculty Research & Creative Works

As the design and fabrication complexities for the instrumentation-on-silicon systems intensify, optimization of combined Built-In Self-Test (BIST) and Automated Test Equipment (ATE) testing becomes more desirable to meet the required fault-coverage while maintaining acceptable cost overhead. The cost associated with combined BIST/ATE testing of such systems mainly consists of the following; (1) the cost induced by the BIST area overhead and (2) the cost induced by the overall testing time. In general, BIST has faster testing speed 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 …

Modeling Switched-Reluctance Machines By Decomposition Of Double Magnetic Saliencies, Farzad R. Salmasi, Babak Fahimi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a novel analytical model for a switched-reluctance machine (SRM) based on decomposition of its inherent double joint magnetic saliencies due to rotor and stator salient poles and saturation of magnetic field at high stator currents. with this method, the magnetic characteristics of the motor, such as flux linkage and incremental inductance, are decomposed to vector functions of rotor position and phase current. Dynamic state and torque equations for the SRM are derived on the basis of this representation. the proposed model is appropriate for online identification and for sensor less position control algorithms. It is easy to …

Determination Of Dielectric Property Profile In Cement-Based Materials Using Microwave Reflection And Transmission Properties, Bharath Akuthota, R. Zoughi, K. E. Kurtis

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave characterization methods are effective means for evaluating dielectric properties of materials and correlating them to their important physical, chemical and mechanical properties. For characterization purposes most materials are considered homogeneous and the measurement of their dielectric properties is fairly straightforward. However, certain materials may be considered inhomogeneous in such a way that their dielectric properties vary in a preferred direction within the material. To evaluate the dielectric property profile of these materials an electromagnetic model is necessary that can be used along with their measured reflection and transmission properties. This paper presents the development of such a model which …

Design And Analysis Of Charge-Transfer Amplifiers For Low-Power Analog-To-Digital Converter Applications, William Joel Marble

Theses and Dissertations

The demand for low-power A/D conversion techniques has motivated the exploration of charge-transfer amplifiers (CTAs) to construct efficient, precise voltage comparators. Despite notable advantages over classical, continuous-time architectures, little is understood about the dynamic behavior of CTAs or their utility in precision A/D converters. Accordingly, this dissertation presents several advancements related to the design and analysis of charge-transfer amplifiers for low-power data conversion.

First, an analysis methodology is proposed which leads to a deterministic model of the voltage transfer function. The model is generalized to any timing scheme and can be extended to account for nonlinear threshold modulation. The model …

On Noncoherent Detection Of Cpm, Michael D. Rice, Erik Perrins

Faculty Publications

This work was supported under a grant from the Air Force ARTM program (Contracts F04700-02-P-0080 and F04700-02-P-0081). It is well understood that the performance of noncoherent receivers with multi-symbol observation intervals approaches that of coherent receivers as the observation interval grows arbitrarily large. However, since complexity also grows exponentially with observation length, there are practical limits to this approach. In this paper we present a noncoherent receiver for continuous phase modulation (CPM) whose structure is a hybrid between existing coherent and noncoherent receiver architectures. The presentation is given in the most general M-ary multi-h terms, with some emphasis on the …

A Tutorial On Text-Independent Speaker Verification, Frédéric Bimbot, Jean-François Bonastre, Corinne Fredouille, Guillaume Gravier, Ivan Magrin-Chagnolleau, Sylvain Meignier, Teva Merlin, Javier Ortega-García, Dijana Petrovska-Delacrétaz, Douglas A. Reynolds

Presidential Fellows Articles and Research

This paper presents an overview of a state-of-the-art text-independent speaker verification system. First, an introduction proposes a modular scheme of the training and test phases of a speaker verification system. Then, the most commonly speech parameterization used in speaker verification, namely, cepstral analysis, is detailed. Gaussian mixture modeling, which is the speaker modeling technique used in most systems, is then explained. A few speaker modeling alternatives, namely, neural networks and support vector machines, are mentioned. Normalization of scores is then explained, as this is a very important step to deal with real-world data. The evaluation of a speaker verification system …

Optimal Pitch, Speed And Fuel Control At Sea, Thomas Hellström

Journal of Marine Science and Technology–Taiwan

This paper discusses algorithms for fuel saving control for large vessels. The fuel saving is achieved by optimizing control at three levels: low level propeller and main engine control, dynamic speed control to avoid peeks in the fuel consumption and finally route planning for optimal speed profiles compensated for varying depth and weather conditions. The control problems involve classical control functions as well as numerical optimization.

Discontinuous Conduction Mode Of Negative Output Elementary Circuit, Jung-Chien Li, Han-Yang Chen

Journal of Marine Science and Technology–Taiwan

The negative output elementary circuit operated in the discontinuous conduction mode is discussed. The voltage transfer gain of this dc-to-dc converter depends on switching frequency, conduction duty ratio, inductance, and load resistance. The condition for the discontinuous conduction mode is derived and verified. The variation ratio of the output voltage is also derived.

Response To Comments On "A Novel Approach To Determine The Astronomical Vessel Position", Jiang-Ren Chang, Chih-Li Chen, Tien-Pen Hsu

Journal of Marine Science and Technology–Taiwan

No abstract provided.

Electron Vacuum Tube Guitar Amplifier, Erik Widman

Honors Theses

This project consisted of designing and fabricating an electron vacuum tube guitar amplifier. Vacuum tubes have become obsolete in modern electronics due to their size, cost, and inefficiency. However, vacuum tubes are still commonly used in guitar amplifiers. Vacuums tube's nonlinear amplifying characteristics are ideal for distorting a signal. Hence vacuum tubes are used in distorting guitar amplifiers commonly used in rock music. While guitar amplifiers consist of many subsystems, the focus of this senior design report is the distorting preamplifier.

Imagine a guitar signal as a pure sine wave (although in reality the signal is a complicated series of …

Synthesis Of Electromagnetic Devices With A Novel Neural Network, Heriberto Jose Delgado, Michael Thursby, Fredric M. Ham

Electrical Engineering and Computer Science Faculty Publications

A novel Artificial Neural Network (ANN) is presented, which has been designed for computationally intensive problems, and applied to the optimization of electromagnetic devices such as antennas and microwave devices. The ANN exploits a unique number representation in conjunction with a more standard neural network architecture. An ANN consisting of a hetero-associative memory provided a very efficient method of computing the necessary geometrical values for the devices, when used in conjunction with a new randomization process. The number representation used provides significant insight into this new method of fault-tolerant computing. Further work is needed to evaluate the potential of this …

Consistency Restoration In Point And Interval Spatio-Temporal Reasoning, Florent Launay, Debasis Mitra

Electrical Engineering and Computer Science Faculty Publications

In this work, we first have proposed a technique to define the “causes” of inconsistency on an online point based reasoning constraint network. Second, we introduce an algorithm that proposes the user a minimal set of relations to remove when inconsistencies are detected. We have developed and implemented a battery of algorithms for the purpose of this type of reasoning. Some useful theorems and properties are defined for proving the ‘minimal’ aspect of the algorithm. Finally, we found that our investigation was a polynomially solvable sub problem of the vertex cover problem.

Hardware Synthesis Of Synchronous Data Flow Models, Matthew R. Koecher

Theses and Dissertations

Synchronous Dataflow (SDF) graphs are a convenient way to represent many signal processing and dataflow operations. Nodes within SDF graphs represent computation while arcs represent dependencies between nodes. Using a graph representation, SDF graphs formally specify a dataflow algorithm without any assumptions on the final implementation. This allows an SDF model to be synthesized into a variety of implementation techniques including both software and hardware.

This thesis presents a technique for generating an abstract hardware representation from SDF models. The techniques presented here operate on SDF models defined structurally within the Ptolemy modeling environment. The behavior of the nodes within …

Construction Of Depth-Structure Shelf-Edge Map For Case Study Of Kujung Formation, East Java Sea, Saifatur Rusli, Suparto Suparto

Makara Journal of Technology

Construction of Depth-Structure Shelf-edge Map for Case Study of Kujung Formation, East Java Sea. In general, reflection seismic method has capability to represent sub-surface in time domain. Seismic cross-section that depicts the formation of sub-surface usually use time domain in the format of TWT (Two Way Times). This due to in the process of seismic data acquisition, seismic wave propagates in down-going and up-going manner so that the obtained results from data processing are in the format of TWT seismic vs. shot points. This paper will describe the construction of depth-structure map for case study of Kujung Formation, East Java …

Metrics For Human Driving Of Multiple Robots, Dan R. Olsen Jr., Jonathan Turner, Stephen Bart Wood

Faculty Publications

A goal of human-robot interaction is to expand the capability of human beings so that they can control multiple robots simultaneously. This provides leverage for human attention beyond single robot interaction. The number of such robots that can be operated is called the fan-out of a human-robot team. We define the concepts of neglect-tolerance as a measure of autonomy and interaction-effort as a measure of required human attention. A model for fan-out is presented that predicts a human's ability to control multiple robots. We validate this model using robot simulations and user studies. Using the validated model we demonstrate enhanced …

An Electromagnetic Model For Evaluating Temporal Water Content Distribution And Movement In Cyclically Soaked Mortar, Shanup Peer, K. E. Kurtis, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Evaluation of water distribution and its temporal movement in cement-based materials is important for assessing cement hydration, curing, and long-term performance. From a practical standpoint, it is also important to obtain this information nondestructively. Near-field microwave nondestructive evaluation methods have proven effective for evaluation of cement-based materials for their various mixture properties, including the detection of salt added to the mixing water and chloride ions entering these materials through exposure to salt water solutions. Electromagnetic modeling of the interaction of microwave signals with moist cement-based materials can provide the necessary insight to evaluate water content distribution and movement in these …

Generating Series For Interconnected Nonlinear Systems And The Formal Laplace-Borel Transform, Yaqin Li

Electrical & Computer Engineering Theses & Dissertations

Formal power series methods provide effective tools for nonlinear system analysis. For a broad range of analytic nonlinear systems, their input-output mapping can be described by a Fliess operator associated with a formal power series. In this dissertation, the inter connection of two Fliess operators is characterized by the generating series of the composite system. In addition, the formal Laplace-Borel transform of a Fliess operator is defined and its fundamental properties are presented. The formal Laplace-Borel transform produces an elegant description of system interconnections in a purely algebraic context.

Specifically, four basic interconnections of Fliess operators are addressed: the parallel, …

Pid Fuzzy Logic Controller System For Dc Motor Speed Control, H. Samsul Bachri M.

Makara Journal of Technology

PID Fuzzy Logic Controller System for DC Motor Speed Control. A good controller system must have resilience to disturbance and must be able to response quickly and accurately. Problem usually appears when PID controller system was built sensitively hence the system’s respon to the disturbance will yield big overshot/undershot then the possibility of oscillation to be happened is excelsior. When the controller system was built insensitively, the overshot/undershot will be small but the recovery time will be longer. Hybrid controller system could overcome those problems by combining PID control system with fuzzy logic. The main control of this system is …

Source Level Debugging Of Circuits Synthesized From High Level Language Descriptions, Karl S. Hemmert

Theses and Dissertations

The rapid increase in the density of modern FPGAs has allowed ever increasingly complex designs to be mapped to FPGAs. However, this increase in logic resources is accompanied by an increase in the complexity of describing and verifying the operation of an application. This has prompted the search for new approaches to the design, debug and verification of circuits. The desire to find more effecient approaches to designing these large FPGA circuits has led to the creation of synthesizing compilers that can create hardware from high-level descriptions based on general purpose programming languages. Being able to describe the application at …

Scaling And Characterization Of Direct Current Glow Discharge Plasma In Atmospheric Air, Abdel-Aleam Hefney Mohamed

Electrical & Computer Engineering Theses & Dissertations

A microhollow cathode discharge was used as a plasma cathode to sustain a stable direct current glow discharge in atmospheric pressure air. The volumetric scale of glow discharge increased from the millimeter to the centimeter range by extending the plasma in lateral and axial directions. In the axial direction, the length of the glow discharge column was varied from 1 mm to 2 cm, with the sustaining voltage increasing linearly with the glow discharge column length. Extension in the lateral direction was obtained by operating discharges in parallel. The glow discharge plasma of the parallel discharge columns was found to …

Data Smoothing And Interpolation Using Eighth-Order Algebraic Splines, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

A new type of algebraic spline is used to derive a filter for smoothing or interpolating discrete data points. The spline is dependent on control parameters that specify the relative importance of data fitting and the derivatives of the spline. A general spline of arbitrary order is first formulated using matrix equations. We then focus on eighth-order splines because of the continuity of their first three derivatives (desirable for motor and robotics applications). The spline's matrix equations are rewritten to give a recursive filter that can be implemented in real time for lengthy data sequences. The filter is lowpass with …

Analysis Of Kancil's Car Knuckle Prototype, Tresna P. Soemardi, Aida Mahmudah

Makara Journal of Technology

Analysis of Kancil’s Knuckle Prototype. The objective of this work is to execute strength analysis of knuckle, which is made from FCD 50, by using static analysis on maximum loading. This maximum loading is obtained from front axle loading calculation on particular operating condition. That is, vehicle is braking while cornering in down hill. From previous vehicle loading calculation, we get a number of loading values on different speed and deceleration. At the end, we get a value of speed and deceleration that guarantee the vehicle safety if it is braking while cornering in down hill. As comparison, loading calculation …