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1996

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Articles 1 - 30 of 107

Full-Text Articles in Electrical and Computer Engineering

Trade-Off Study And Computer Simulation For Assessing Spacecraft Pointing Accuracy And Stability Capabilities, Marcelo C. Algrain, Richard M. Powers Dec 1996

Trade-Off Study And Computer Simulation For Assessing Spacecraft Pointing Accuracy And Stability Capabilities, Marcelo C. Algrain, Richard M. Powers

Department of Electrical and Computer Engineering: Faculty Publications

A case study, written in a tutorial manner, is presented where a comprehensive computer simulation is developed to determine the driving factors contributing to spacecraft pointing accuracy and stability. Models for major system components are described. Among them are spacecraft bus, attitude controller, reaction wheel assembly, star-tracker unit, inertial reference unit, and gyro drift estimators (Kalman filter). The predicted spacecraft performance is analyzed for a variety of input commands and system disturbances. The primary deterministic inputs are the desired attitude angles and rate set points. The stochastic inputs include random torque disturbances acting on the spacecraft, random gyro bias noise, …

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Ellipsometer/Polarmeterbased Process Monitor And Control System Suitable For Simultaneous Retrofit On Molecular Beam Epitaxy System Rheed/Leed Interface System, And Method Of Use, John A. Woollam, Blaine D. Johs, Peter P. Chow Dec 1996

Ellipsometer/Polarmeterbased Process Monitor And Control System Suitable For Simultaneous Retrofit On Molecular Beam Epitaxy System Rheed/Leed Interface System, And Method Of Use, John A. Woollam, Blaine D. Johs, Peter P. Chow

Department of Electrical and Computer Engineering: Faculty Publications

A method of, and system for applying light beam producing systems, such as ellipsometers, polarimeters, polarized light reflectance and functionally similar systems, such that a beam of light produced thereby is caused to be incident upon a process element at an angle in excess of an associated Brewster angle while enabling the production of a signal sufficiently sensitive to changes in process element parameters, for use in "real-time" process element process monitoring and control, is disclosed. In addition, a process element processing system and electron beam producing system and light beam producing system combination system is taught, wherein the electron …

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Ellipsometer/Polarmeter Based Process Monitor And Control System Suitable For Simultaneous Retrofit On Molecular Beam Eptaxy System Rheed/Leed Interface System, And Method Of Use, John A. Woollam, Blaine D. Johs, Peter P. Chow Dec 1996

Ellipsometer/Polarmeter Based Process Monitor And Control System Suitable For Simultaneous Retrofit On Molecular Beam Eptaxy System Rheed/Leed Interface System, And Method Of Use, John A. Woollam, Blaine D. Johs, Peter P. Chow

Department of Electrical and Computer Engineering: Faculty Publications

A method of, and system for, applying light beam producing systems such as ellipsometers, polarimeters, polarized light reflectance and functionally similar systems, such that a beam of light produced thereby is caused to be incident upon a process element at an angle in excess of an associated Brewster angle while enabling the production of a signal sufficiently sensitive to changes in process element parameters, for use in "real-time' process element process monitoring and control, is disclosed. In addition a process element processing system and electron beam producing system and light beam producing system combination system is taught, wherein the electronbeam …

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Properties Of Schottky Contacts Of Aluminum On Strained Si1-X-YGeXCY Layers, Jian Mi, Ashawant Gupta, Cary Y. Yang Dec 1996

Properties Of Schottky Contacts Of Aluminum On Strained Si1-X-YGeXCY Layers, Jian Mi, Ashawant Gupta, Cary Y. Yang

Electrical and Computer Engineering

Schottky contacts of Al/Si1-x-yGexCy were fabricated using conventional Si technology. Effects of thermal processing of the alloys on the electrical properties of the Al/Si1-x-yGexCy Schottky diodes were investigated. Current–voltage (I–V), capacitance–voltage (C–V), and x‐ray diffraction measurements were performed. These thick alloy films (100–150 nm) experienced strain relaxation upon annealing at 700 °C. Nearly ideal I–V and C–V behaviors were obtained for strain‐compensated samples. I–V and C–Vcharacteristics show evidence of dislocation‐related traps for strain‐relaxed samples. Carbon incorporation improves the I–V and C–V characteristics by lessening the extent of lattice relaxation due …

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Growth Of Diamond By Rf Plasma-Assisted Chemical Vapor Deposition, Duane E. Meyer, Natale J. Ianno, John A. Woollam, A. B. Swartzlander, A. J. Nelson Dec 1996

Growth Of Diamond By Rf Plasma-Assisted Chemical Vapor Deposition, Duane E. Meyer, Natale J. Ianno, John A. Woollam, A. B. Swartzlander, A. J. Nelson

Department of Electrical and Computer Engineering: Faculty Publications

A system has been designed and constructed to produce diamond particles by inductively coupled radio-frequency, plasma-assisted chemical vapor deposition. This is a low-pressure, low-temperature process used in an attempt to deposit diamond on substrates of glass, quartz, silicon, nickel, and boron nitride. Several deposition parameters have been varied including substrate temperature, gas concentration, gas pressure, total gas flow rate, rf input power, and deposition time. Analytical methods employed to determine composition and structure of the deposits include scanning electron microscopy, absorption spectroscopy, scanning Auger microprobe spectroscopy, and Raman spectroscopy. Analysis indicates that particles having a thin graphite surface, as well …

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A Stochastic Model For Crystal-Amorphous Transition In Low Temperature Molecular Beam Epitaxial Si(111), R. Venkatasubramanian, Suresh Gorantla, S. Muthuvenkatraman, Donald L. Dorsey Dec 1996

A Stochastic Model For Crystal-Amorphous Transition In Low Temperature Molecular Beam Epitaxial Si(111), R. Venkatasubramanian, Suresh Gorantla, S. Muthuvenkatraman, Donald L. Dorsey

Electrical & Computer Engineering Faculty Research

Molecular beam epitaxial Si (111) grown below a certain temperature result in amorphous structure due to the limited surface mobility of atoms in finding correct epitaxial sites. In spite of many experimental and theoretical studies, the mechanism of crystal‐amorphous transition and its dynamics related to the growth conditions are not well understood. In this article, we present a theoretical model based on the formation of stacking fault like defects as a precursor to the amorphous transition of the layer. The model is simulated based on a stochastic model approach and the results are compared to that of experiments for temperatures …

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A Multimedia Manual On The World Wide Web For Telecommunications Equipment, Andrew L. Sears, Steve E. Watkins Dec 1996

A Multimedia Manual On The World Wide Web For Telecommunications Equipment, Andrew L. Sears, Steve E. Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

An interactive multimedia educational manual on the Internet through the World Wide Web for commercial optical fiber telecommunications equipment is described. The Telecommunications Laboratory Manual is a vehicle for enhancing engineering education with realistic laboratory or virtual laboratory experience. The manual provides a brief system tutorial, operating instructions, on-line help, and multimedia experimental demonstrations. It incorporates block diagrams, photographic images, and hypertext links that are mouse clickable, allowing users to access documents or links describing components or processes in any order. An experimental section guides students through laboratory experiences, demonstrates selected equipment characteristics, and provides for direct instructor contact through …

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Three-Dimensional Display Utilizing A Diffractive Optical Element And An Active Matrix Liquid Crystal Display, Gregory P. Nordin, M. W. Jones, S. T. Kowel, J. H. Kulick, R. G. Lindquist Dec 1996

Three-Dimensional Display Utilizing A Diffractive Optical Element And An Active Matrix Liquid Crystal Display, Gregory P. Nordin, M. W. Jones, S. T. Kowel, J. H. Kulick, R. G. Lindquist

Faculty Publications

We describe the design, construction, and performance of the first real-time autostereoscopic three-dimensional (3-D) display based on the partial pixel 3-D display architecture. The primary optical components of the 3-D display are an active-matrix liquid crystal display and a diffractive optical element (DOE). The display operates at video frame rates and is driven with a conventional VGA signal. Three-dimensional animations with horizontal motion parallax are readily viewable as sets of stereo images. Formation of the virtual viewing slits by diffraction from the partial pixel apertures is experimentally verified. The measured contrast and perceived brightness of the display are excellent, but …

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Detection For A Statistically-Known, Time-Varying Dispersive Channel, David W. Matolak, S. G. Wilson Dec 1996

Detection For A Statistically-Known, Time-Varying Dispersive Channel, David W. Matolak, S. G. Wilson

Faculty Publications

Detection for the statistically known channel (SKC) is aimed at obtaining good performance in situations where our statistical knowledge of a time-varying channel is good, and where other equalization/detection schemes are either too complex to implement, or their performance is limited due to the rapidity of channel fading, or where we are simply unable to perform channel estimation. By using a statistical characterization of the channel, we develop a new detector that performs maximum-likelihood sequence estimation (MLSE) (given the channel model) on blocks of N symbols. Both symbol-spaced and fractionally spaced samples are used, to obtain two different detectors, that …

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A State Space Modeling And Control Method For Multivariable Smart Structural Systems, Robert Butler, Vittal S. Rao Dec 1996

A State Space Modeling And Control Method For Multivariable Smart Structural Systems, Robert Butler, Vittal S. Rao

Electrical and Computer Engineering Faculty Research & Creative Works

A system identification technique for the derivation of minimal, continuous time state variable models for multivariable smart structural systems is presented. The structural identification technique is based on the measurement of eigenvalues and eigenvectors of the structure. Two sensors are required for each mode included in the structural system model. Unlike computational system identification techniques, the relatively large number of sensors simplifies the identification process making it ideal for systems with several inputs and outputs. Additionally, the identification technique allows the implementation of multi-input multi-output full state feedback controllers with simple analog hardware. The amount of hardware required for the …

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Automated State Model Generation Algorithm For Power Circuits And Systems, O. Wasynczuk, Scott D. Sudhoff Dec 1996

Automated State Model Generation Algorithm For Power Circuits And Systems, O. Wasynczuk, Scott D. Sudhoff

Electrical and Computer Engineering Faculty Research & Creative Works

A new approach of automatically generating state-space models of power circuits and systems is presented. In this approach, the composite system state equations are established algorithmically given the standard node incidence matrix and elementary branch data (e.g. resistances, inductances, back emf's). The resulting state equations can be solved using a variety of numerical techniques or commercially available computer simulation programs. An example system consisting of a three-phase generator and rectifier load is used to illustrate this approach. Experimental verification is also provided. © 1996 IEEE.

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A Voltage Control Strategy For Current-Regulated Pwm Inverters, Oleg Wasynczuk, Scott D. Sudhoff, Tin D. Tran, David H. Clayton, Henry J. Hegner Dec 1996

A Voltage Control Strategy For Current-Regulated Pwm Inverters, Oleg Wasynczuk, Scott D. Sudhoff, Tin D. Tran, David H. Clayton, Henry J. Hegner

Electrical and Computer Engineering Faculty Research & Creative Works

Alternative voltage control strategies for current-regulated PWM inverters are analyzed, including previously established feedforward and feedforward/feedback controllers and a newly proposed decoupling feedback control strategy. The steady-state and dynamic characteristics of each of these control methods are illustrated and compared for a selected inverter design. It is shown that the feedforward controller exhibits steady-state error and an undesirable overshoot of the output voltages during startup. The addition of a feedback loop eliminates the steady-state error and reduces the overshoot; however, the natural response is underdamped regardless of the choice of feedback gains. A decoupling feedback control strategy that eliminates the …

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Controlling Three-Axis Attitude Rates On A Pointing System Using Nonlinear Observer And Two Axis Measurements, Marcelo C. Algrain Nov 1996

Controlling Three-Axis Attitude Rates On A Pointing System Using Nonlinear Observer And Two Axis Measurements, Marcelo C. Algrain

Department of Electrical and Computer Engineering: Faculty Publications

A new observer design method that allows for estimating the angular rates along a vehicle’s three principal axes is described. The observer uses measurements from a single two-axis angular rate sensor (gyro) and determines the rates for the third axis using a nonlinear observer. Unlike conventional approaches where the equations governing vehicle motion (Euler’s equations) are linearized and then an observer is constructed based on the linear model, this method does not require linearization of the system. Instead, a pseudo-linear representation is used. The pseudo-linear model is obtained by systematically decomposing a nonlinear system into linear and nonlinear terms. The …

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Application Of Inversions To Lossless Image Compression, Ziya Arnavut Nov 1996

Application Of Inversions To Lossless Image Compression, Ziya Arnavut

Department of Electrical and Computer Engineering: Faculty Publications

Linear prediction schemes, such as that of the Joint Photographic Experts Group (JPEG), are simple and normally produces a residual sequence with lower zero-order entropy. Occasionally the entropy of the prediction error becomes greater than that of the original image. Such situations frequently occur when the image data have discrete gray levels located within certain intervals. To alleviate this problem, various authors have suggested different preprocessing methods. However, the techniques reported require two passes. We extend the definition of Lehmer-type inversions (Lehmer 1960 and 1964) from permutations to multiset permutations and present a one-pass algorithm based on inversions of a …

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Arts, Computers And Artificial Intelligence, Sol Neeman Ph.D. Nov 1996

Arts, Computers And Artificial Intelligence, Sol Neeman Ph.D.

Engineering Studies Faculty Publications and Creative Works

Science and art seem to belong to different cultures. Science and technology, mainly the products of the intellect, use terminology and vocabulary that are concise and well defined. In contrast, in artistic expression, ambiguity is a powerful component. Still the relationship between these two different categories of human activity is interesting and fascinating. In this paper, a general comparison of these two disciplines will be introduced. Then the possibility of mechanical creation of art using computers and artificial intelligence will be discussed. This will be followed by two techniques which are used to create poetry and music. First, a statistical …

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Oxygen Plasma Asher Contamination: An Analysis Of Sources And Remedies, R. A. Synowicki, Jeffrey S. Hale, William A. Mcgahan, Natale J. Ianno, John A. Woollam Nov 1996

Oxygen Plasma Asher Contamination: An Analysis Of Sources And Remedies, R. A. Synowicki, Jeffrey S. Hale, William A. Mcgahan, Natale J. Ianno, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

The low Earth orbit (LEO) environment is commonly simulated using oxygen plasma ashers to determine the effects of LEO on spacecraft materials. However, plasma ashers can also contaminate samples during plasma exposure, making them less than ideal for space simulation. This study results from attempts to minimize or eliminate contamination. Optical methods of variable angle spectroscopic ellipsometry and reflectance spectrophotometry were used to quantify contaminant stoichiometry and deposition rate. Auger electron spectroscopy identified deposited contaminants and their surface coverage. Contamination results from etching of the rubber chamber seals by the plasma. The deposited contaminant was nearly indistinguishable from fully stoichiometric …

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A Real-Time Self-Tuning Web Tension Regulation Scheme, Brian T. Boulter, Zhiqiang Gao Nov 1996

A Real-Time Self-Tuning Web Tension Regulation Scheme, Brian T. Boulter, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

A self-tuning control scheme is proposed for tension regulation in a web transport system. A computationally efficient self-tuning method is first described. The frequency domain model of the plant is then described. Simulations of the on-line tuning are presented. The paper closes with a discussion of cognizant real-time implementation issues.

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Generalized Beam Matrices. Iii. Application To Diffraction Analysis, Lee W. Casperson, Anthony A. Tovar Nov 1996

Generalized Beam Matrices. Iii. Application To Diffraction Analysis, Lee W. Casperson, Anthony A. Tovar

Electrical and Computer Engineering Faculty Publications and Presentations

In analogy with Huygen’s wavelets a new method based on Gaussian beamlets is used to develop a conventional diffraction integral formalism for paraxial optical systems representable by complex 2×2 ABCD Gaussian beam matrices. This method, along with a new phase parameter transformation, is then used to produce a new diffraction integral for studying the propagation of light beams with arbitrary spatial profiles through much more general misaligned complex optical systems representable by 3×3 ABCDGH beam matrices.

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Investigation Of Fundamental Emi Source Mechanisms Driving Common-Mode Radiation From Printed Circuit Boards With Attached Cables, David M. Hockanson, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha, Michael J. Wilhelm Nov 1996

Investigation Of Fundamental Emi Source Mechanisms Driving Common-Mode Radiation From Printed Circuit Boards With Attached Cables, David M. Hockanson, James L. Drewniak, Todd H. Hubing, Thomas Van Doren, Fei Sha, Michael J. Wilhelm

Electrical and Computer Engineering Faculty Research & Creative Works

Fundamental EMI source mechanisms leading to common-mode radiation from printed circuit boards with attached cables are presented in this paper. Two primary EMI source mechanisms have been identified: one associated with a differential-mode voltage and another associated with a differential-mode current, both of which result in a common-mode current on an attached cable. These mechanisms can be used to relate printed circuit layout geometries to EMI sources. The two mechanisms are demonstrated through numerical and experimental results, and an example from a production printed-circuit design is presented.

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Novel High-Speed Architecture For Machine Vision Applications, Bassam S. Farroha, Raghvendra G. Deshmukh Oct 1996

Novel High-Speed Architecture For Machine Vision Applications, Bassam S. Farroha, Raghvendra G. Deshmukh

Electrical Engineering and Computer Science Faculty Publications

This paper focuses on producing a state-of-the-art technique for designing an image recognition system for machine vision applications. The motivation behind the new system design is to provide a unique methodology, using strategic design techniques, to implement a system that addresses real-world image recognition applications. The introduction of application-specific, massively parallel array of processors, where low-level processing is accomplished on reconfigurable hardware structures, highlights the scheme. The system was built and simulated on a VLSI chip and results were verified using Electric Rules Check and Harris Timing Analysis examination tools. The system is composed of there functional layers and a …

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Infrared Quarter-Wave Reflection Retarders Designed With High-Spatial-Frequency Dielectric Surface-Relief Gratings On A Gold Substrate At Oblique Incidence, Jian Liu, Rasheed M.A. Azzam Oct 1996

Infrared Quarter-Wave Reflection Retarders Designed With High-Spatial-Frequency Dielectric Surface-Relief Gratings On A Gold Substrate At Oblique Incidence, Jian Liu, Rasheed M.A. Azzam

Electrical Engineering Faculty Publications

One- and two-dimensional high-spatial-frequency dielectric surface-relief gratings on a Au substrate are used to design a high-reflectance quarter-wave retarder at 70° angle of incidence and 10.6-μm light wavelength. The equivalent homogeneous anisotropic layer model is used. It is shown that equal and high reflectances (>98.5%) for the p and the spolarizations and quarter-wave retardation can be achieved with two-dimensional ZnS surface-relief gratings. Sensitivities to changes of incidence angle, light wavelength, grating filling factor, and grating layer thickness are considered.

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Detecting Stress And Fatigue Cracks, Christian J. Huber, R. Zoughi Oct 1996

Detecting Stress And Fatigue Cracks, Christian J. Huber, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Discoveries in using open ended rectangular waveguides for microwave surface crack detection and sizing have generated interest. The foundation, potential, advantages and disadvantages of this methodology, developed at the Applied Microwave Nondestructive Testing Laboratory in the Electrical Engineering Department at Colorado State University, are discussed. Microwave techniques in general and this particular approach offer certain unique advantages that can advance the state of the art of fatigue/surface crack detection. The basic features and capabilities of this technique have been theoretically and experimentally investigated these past few years. However, more developmental work is needed to bring this technique from the laboratory …

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Generation Of Synthetic-Focus Images From Pulse-Echo Ultrasound Using Difference Equations, Daryl G. Beetner, R. Martin Arthur Oct 1996

Generation Of Synthetic-Focus Images From Pulse-Echo Ultrasound Using Difference Equations, Daryl G. Beetner, R. Martin Arthur

Electrical and Computer Engineering Faculty Research & Creative Works

To produce a complete-dataset, pulse-echo image requires a knowledge of the time of flight (TOF) from each source to each sensor in the transducer array for each site to be imaged. Increasing the speed of TOF calculation is important in adaptive-focus schemes. The authors determined TOF more rapidly than via direct calculation by representing TOF surfaces by two-dimensional (2-D), positive-integer-degree polynomials implemented in their forward-difference form. Errors which accumulate due to the use of a difference equation depend on the degree of the polynomial and on the size of the image. The number of bits needed to address echo samples …

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Nlo Waveguide "And" Switch And Method Therefor, John J. Kester, Iyad A. Dajani, Peter M. Ranon, Thomas G. Alley Sep 1996

Nlo Waveguide "And" Switch And Method Therefor, John J. Kester, Iyad A. Dajani, Peter M. Ranon, Thomas G. Alley

AFIT Patents

Method and apparatus are provided for NLO switching by first providing a phase-matched SHG grating which outputs a reinforced SHG beam only when two input beams of frequency (ω) are present in two modes of such wg. The so encoded NLO switch is operated by directing at least two input pulsed laser beams of frequency (ω) into the two modes of the wg to generate a reinforced pulsed output SHG beam and output same from the wg in an NLO switching process. The two input beams desirably have a separate pulse train and the spatial and temporal overlap of the …

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Determination Of The Refractive Index And Thickness Of Transparent Pellicles By Use Of The Polarization-Independent Absentee-Layer Condition, Y. Cui, R. M.A. Azzam Sep 1996

Determination Of The Refractive Index And Thickness Of Transparent Pellicles By Use Of The Polarization-Independent Absentee-Layer Condition, Y. Cui, R. M.A. Azzam

Electrical Engineering Faculty Publications

The refractive index and the thickness of a transparent pellicle are determined when the pellicle is placed between two vertical crossed polarizers and rotated in the horizontal plane. The transmission axes of the polarizers are neither parallel nor perpendicular to the plane of incidence. The light transmitted through the crossed polarizers reaches a minimum when the pellicle satisfies the absentee-layer condition. The refractive index and the film thickness are obtained from the pellicle orientation angles under such a condition.

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Hybrid Kalman / Minimax Filtering In Phase-Locked Loops, Daniel J. Simon, Hossny El-Sherief Sep 1996

Hybrid Kalman / Minimax Filtering In Phase-Locked Loops, Daniel J. Simon, Hossny El-Sherief

Electrical and Computer Engineering Faculty Publications

A method of combining Kahnan filtering and minimax filtering is proposed and demonstrated in an application to phase-locked loop design. Kalman filtering suffers from a lack of robustness to departures from the assumed noise statistics. Minimax filtering, however, has the drawback of ignoring the engineer's (admittedly incomplete) knowledge of the noise statistics. It is shown in this paper that hybrid Kalman/minimax filtering can provide the “best of both worlds” . Phase-locked loop filter design is used in this paper to demonstrate an application of hybrid estimation.

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Globally Optimal Periodic Robot Joint Trajectories, Daniel J. Simon Sep 1996

Globally Optimal Periodic Robot Joint Trajectories, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

This paper presents a new method for the planning of robot trajectories. The method presented assumes that joint-space knots have been generated from Cartesian knots by an inverse kinematics algorithm. The method is based on the globally optimal periodic interpolation scheme derived by Schoenberg, and thus is particularly suited for periodic robot motions. Of all possible periodic joint trajectories which pass through a specified set of knots, the trajectory derived in this paper is the ‘best’. The performance criterion used is the integral (over one period) of a combination of the square of the joint velocity and the square of …

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Real-Time Optically Processed Face Recognition System Based On Arbitrary Moiré Contours, Rafael A. Andrade, Bernard R. Gilbert, Donald W. Dawson, Chris L. Hart, Samuel Peter Kozaitis, Joel H. Blatt Sep 1996

Real-Time Optically Processed Face Recognition System Based On Arbitrary Moiré Contours, Rafael A. Andrade, Bernard R. Gilbert, Donald W. Dawson, Chris L. Hart, Samuel Peter Kozaitis, Joel H. Blatt

Electrical Engineering and Computer Science Faculty Publications

We demonstrate a hybrid electronic-optical real-time system that performs 3-D face recognition. We constructed custom reference gratings that formed a desired moire pattern when mixed with images of structurally illuminated faces. The moiré patterns could be in any form such as, equal depth contours, error maps, or any arbitrary pattern. We demonstrate video methods to generate such error maps in real time, thus developing a real-time automated face recognition system based on the optical processing of arbitrary moiré contours. We chose the moiré pattern to be in the form of a Fresnel zone plate, which is displayed on a liquid …

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An Empirical Comparison Of Area-Universal And Other Parallel Computing Networks, Ronald I. Greenberg, Lee Guan Sep 1996

An Empirical Comparison Of Area-Universal And Other Parallel Computing Networks, Ronald I. Greenberg, Lee Guan

Computer Science: Faculty Publications and Other Works

This paper provides empirical comparison of the communication capabilities of two area-universal networks, the fat-tree and the fat-pyramid, to the popular mesh and hypercube networks for parallel computation. While area-universal networks have been proven capable of simulating, with modest slowdown, any computation of any other network of comparable area, prior work has generally left open the question of how area-universal networks compare to other networks in practice. Comparisons are performed using techniques of throughput and latency analysis that have previously been applied to k-ary n-cube networks and using various existing models to equate the hardware cost of the networks being …

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Real-Time Range Image Segmentation Using Adaptive Kernels And Kalman Filtering, Fred W. Depiero, Mohan M. Trivedi Aug 1996

Real-Time Range Image Segmentation Using Adaptive Kernels And Kalman Filtering, Fred W. Depiero, Mohan M. Trivedi

Electrical Engineering

Segmentation is a fundamental process affecting the overall quality and utility of a machine vision system. Range Profile Tracking (RPT) is a systematic approach for stable, accurate and high speed segmentation of range images that is based on Kalman filtering. Tests of RPT have produced stable decompositions of second order surfaces bounded by jump and crease discontinuities, having a volumetric error of a few percent, in under 6 sec. for a wide variety of conditions. Results from over 900 tests on synthetic scenes and 150 real range images are presented.

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