Engineering Commons^™

Inverse Synthetic Aperture Radar Imaging Using A Coherent Ultrawideband Random Noise Radar System, Daryl C. Bell, Ram M. Narayanan

Department of Electrical and Computer Engineering: Faculty Publications

The University of Nebraska-Lincoln has developed an ultrawideband random noise radar operating over the 1- to 2-GHz frequency range. The system uses the technique of heterodyne correlation, and is thus phase coherent. It has therefore been used in applications such as interferometry, polarimetry, and Doppler estimation. This assesses the performance of this radar as a range-Doppler imaging system, in particular, inverse synthetic aperture radar (ISAR). By performing turntable experiments, we examine a number of issues that arise both from the wideband nature of the radar system and from the randomness of the transmit signal. Although the ultrawideband nature of the …

Production Of Microcrystalline Cellulose By Reactive Extrusion, Milford Hanna, Gerald Biby, Vesselin Miladinov

Industrial Agricultural Products Center: Publications and Information

This process involves feeding cellulose into an extruder with an acid solution. The extruder is comprised of a screw and a barrel. The screw is rotated so as to pressurize the cellulose, and the cellulose undergoes acid hydrolysis and forms microcrystalline cellulose. The invented process can be accomplished by using pure cellulose or a lignocellulosic material as the starting material. If a lignocellulosic material is used, then a basic solution is added to it and the lignocellulosic material is fed through an extruder so as to obtain a mixture comprising lignin, hemicellulose and cellulose. The lignin and hemicellulose are extracted …

Apparatus And Method For Three-Dimensional Contouring, Carl B. Kieranen, Charles A. Hallstrom, Glen R. Simula, Nils P. Ruonavaara, James D. Waineo

Michigan Tech Patents

A contouring device and method for contouring three- dimensionally curved surfaces includes an elongated contouring assembly that is supported at opposite ends by a pair of fluid cylinders. The fluid cylinders are controlled to raise and lower the ends of the contouring assembly independently of each other, thereby allowing the contouring assembly to create a three-dimensionally curved surface as it passes over an area to be contoured. The control of one of the fluid cylinders is based on a comparison of the measured position of a first end of the contouring assembly with a profile of the surface to be …

Effects Of Filament Reinforced Plexiglass Pressure Vessel On Failure Analysis, Faysal A. Kolkailah, Eltahry Elghandour, Luis J. Valenzuela

Aerospace Engineering

This paper presents an investigation into the effect of reinforcing a Plexiglas tube with fiberglass/epoxy threads wound at different angles. This paper shows an experimental analysis approach to find the ultimate failure pressure of these vessels. The properties of the Plexiglas, fiberglass, orientation (wind) angle and the matrix were taken into account to determine their effects on the ultimate failure pressure of the vessels. Mandrels were wound at +/- 75, +/- 65, and +/- 55 deg, and specimen were cut out from each to 19.05 cm long, 7.62 cm inner diameter and outer diameters dependent of the wind angle. The …

The Study Of Empirical Methodology To Observe Damping Characteristics Of Various Laminate Composite Plates, Faysal A. Kolkailah, Eltahry Elghandour, Taikha Oh, Jason Bolosan

Aerospace Engineering

Modifying the stiffness of the structure is usually not a feasible solution to enhancing damping, since changing the stiffiless effects the natural frequency changing and eventually the condition of resonance will be reached. Therefore, one of the recommendatory ways to reduce the response on structural elements is to improve damping characteristics. The objectives of this study are to present empirical methodology to detect damping characteristics of structural elements, and determine the optimal location of sensor to detect structural failure by analyzed data from both experimental and numerical analysis. Using orthotropic composite plates comprised of 977-2 Carbon fiber/IM7 epoxy, the natural …

7v Tristate-Capable Output Buffer Implemented In Standard 2.5v Cmos Process, Vladimir I. Prodanov, Vito Boccuzzi

Electrical Engineering

This paper describes high-voltage CMOS buffer architecture that uses low-voltage transistors. The voltage capability of the presented architecture is nearly three times larger than the voltage capability of the used MOSFET's. This buffer topology could be used to provide 3.3 V compatibility of 1.2 V and 1.5 V digital ICs implemented in standard CMOS technology. A 7 V circuit-prototype was fabricated in 0.25 /spl μ/m 2.5 V CMOS technology. Performed measurements demonstrate stress-free operationin both active and high-impedance mode.

Robust High-Pass And Notch Gm - (Grounded) C Biquads: How Many Different Topologies Are There?, Vladimir I. Prodanov

Electrical Engineering

This paper deals with Gm-C biquadratic filters that use grounded capacitors. We derive all practical HP and notch filter topologies that do not require critical component matching. The aim of this derivation was to discover new architectures. The result of this derivation is quite unexpected: there are only three distinct topologies (one notch and: two high-pass). None of them is particularly new because all reported in the literature biquad circuits are their embodiments.

Ky-Ctds Kentucky Contract Time Determination System (Kyspr 99-195-Lf), Donn E. Hancher, Raymond F. Werkmeister

Kentucky Transportation Center Research Report

This paper reports on the results of research that was funded by the Kentucky Transportation Cabinet (KyTC) to develop a new method for determining construction contract time for its highway construction contracts. The current and other DOT systems were analyzed to determine how a new system could provide better estimated duration. It was pre-determined that a PC computer based system was best suited. The development of the system input was developed from KyTC engineers with construction experience. The study advisory committee worked with Kentucky Transportation Center research engineers to develop the basis for the new contract time determination system, called …

First Casi/Utias Workshop On Low-Cost Space System: University Of Toronto, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "First CASI/UTIAS Workshop on Low-Cost Space System: University of Toronto" from May 4, 2001.

Cybersecurity Considerations With The Increasing Uses Of Small Unmanned Aircraft Systems (Suas) Or Drones, Matthew Kucharek, Stanley Mierzwa

Center for Cybersecurity

The effort to produce this information resource results from a collaborative effort between the Bergen County Technical Schools (high school), through the advisor Andrea Buccino, and a cybersecurity expert mentor. High school senior members of this learning partnership are provided with an interactive learning experience. They gain an increase and knowledge in a particular area of study while under the topical guidance of a mentor. In this example, the high school senior is pursuing coursework in Aerospace Engineering, and this was combined with the focus of cybersecurity to expand the students’ cross-discipline knowledge. This collaborative work was done virtually, given …

Medlink, Nicolas Ehalt

Honors Capstones

Capstone submitted as a graduation requirement for the BSU Honors Program.

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 17, Number 8, May 2001, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Acuta Enews May 2001, Vol.30, No. 5

ACUTA Newsletters

ACUTA Leadership Awards

Assigned to EDUCASUE

DC Update

Overheard on the Listserve: LECs, CLECs, and Resale

Board Report

Welcome New Members

Positions Available

Assessing The Predictive Accuracy Of Complex Simulation Models, Timothy Ross, Vladik Kreinovich, Cliff Joslyn

Departmental Technical Reports (CS)

No abstract provided.

Asymmetric Low-Velocity Impact Of A Finite Layer, Minggang Zhou, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The dynamic indentation of structural elements such as beams and plates continues to be an intriguing problem, especially for scenarios where large area contacts can occur. Standard methods of indentation analysis typically use a dynamic beam theory solution to obtain an overall load-displacement relationship and then a Hertzian contact solution to determine local stresses under the impactor. However, previous static and dynamic modeling efforts have shown that the stress distribution in the contact region will differ significantly from a Hertzian one when the contact length exceeds the thickness of the beam. In such cases point contact can no longer be …

Strain Rate And Aging Effect On The Mechanical Properties Of Sheet Steels, Chi Ling Pan, Shaojie Wu, Wei Wen Yu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study was primarily involved with the experimental determination of the dynamic mechanical properties of five different sheet steels. The nominal yield strengths of these five types of sheet steels ranged from 172 to 690 MPa (25-100 ksi) and the range of strain rates varied from 10-4 to 1.0 mm/mm/s. All these five materials were studied in both longitudinal and transverse directions under various strain rates, and some materials were also tested under different strain rates and different amounts of prior cold stretching. In addition, two types of steels were tested to estimate the aging effect on the mechanical properties …

Can Computers Do The Job Of Nobelist Physicists? Planck Formula Revisited, Richard Alo, Raul Trejo, Vladik Kreinovich

Departmental Technical Reports (CS)

There exist several computer programs which successfully model the discovery process in science. There are successful expert systems in medicine and other areas. But one area is a real challenge for such systems: theoretical physics. The most advanced knowledge discovery programs (like BACON written under the supervision of the Nobelist Herbert A. Simon) successfully reproduce only 17, 18, and 19 century physics, but stop short of explaining the very first formula of the 20 century: Planck's law of black body radiation. This law, discovered by an insight, led to the modern Quantum Physics. The programs stop short not because the …

Diagnostic Load Testing Of Two-Way Posttensioned Concrete Slab, Antonio Nanni, M. Mettemeyer

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Diagnostic load testing techniques have been used to verify in situ that existing structures have the required load-carrying capacity. This paper discusses the diagnostic load testing and finite-element modeling of a two-way posttensioned concrete slab with the purpose of illustrating the features of this full-scale testing method. The slab was modeled using a commercial finite-element package and the results were verified experimentally. The test loads were applied using hydraulic jacks. Negative internal bending moments were generated at critical locations equivalent to those produced by a 92 psf (4.40 kPa) superimposed uniformly distributed load. Positive internal bending moments were also produced …

Measurement Of Linewidth Enhancement Factor Of Semiconductor Lasers Using An Injection-Locking Technique, G. Liu, Xiaomin Jin, Shun-Lien Chuang

Electrical Engineering

A new method for measuring the linewidth enhancement factor of semiconductor lasers using the injection-locking technique is presented. This idea is based on the relation between the upper and lower bounds of the locked and unlocked regimes when the detuning of the pump and slave laser is plotted as a function of the injection power. Our results are confirmed with an independent measurement using amplified spontaneous emission (ASE) spectroscopy as well as our theory, which takes account of the realistic quantum-well (QW) band structure and many-body effects. This method provides a new approach to measure the linewidth enhancement factor above …

The Need For Emphasis On Teaching The Content Of Certain Subject Areas And Teaching Concepts Related To Certain Packaging Industry Job Titles As Perceived By Packaging Professionals In Indiana And The Surrounding States, Marion D. Schafer

All-Inclusive List of Electronic Theses and Dissertations

The study investigates the opinions or packaging professionals about an appropriate curriculum for a Bachelor of Science degree program in packaging. The study was conducted by surveying packaging profossionals randomly seleclcd from the Central Indiana Institute of Packaging Professionals mailing list. This list was made up mostly of Indiana residents but included a few residents from the fhur surrounding slates. The study was initiated as a first step in the process of developing appropri.ite improvements to the curriculum for the Bachelor of Science degree in packaging al Indiana State University. Six packaging job titles and twenty-three su~jcct areas were chosen …

Factors Affecting The Quality Of Dry Shotcrete, El Rasheid Mohamed Abdalla El Khidir

Archived Theses and Dissertations

No abstract provided.

Axial Strength Of Purlins Attached To Standing Seam Roof Panels, John A. Stolarczyk, James M. Fisher

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

The purpose of this research was to determine the axial load capacity of Z-purlins with one flange attached to a standing seam roof system. The axial load capacity was determined by developing a relationship between the flexural uplift buckling strength and the axial buckling strength in the Z-purlin. This relationship was investigated using finite element models and by conducting a parametric study. At the conclusion of the parametric study, confirmatory tests were conducted to verify the finite element results. Lastly, a relationship has been provided that relates the axial buckling strength in the Z-purlin to the flexural uplift buckling strength.

Infrared Optical Properties Of Aged Porous Gaas, S. Zangooie, Mathias Schubert, T. E. Tiwald, John A. Woollam

Department of Electrical and Computer Engineering: Faculty Publications

Aging properties of porous GaAs were investigated nondestructively using variable angle of incidence infrared spectroscopic ellipsometry. In addition to the thickness and volume porosity, properties of the solid part of the porous material are investigated in terms of the long-wavelength dielectric function and chemical composition. The high sensitivity is employed to detect and identify infrared resonant absorptions related to different vibration modes of cubic and amorphous As₂O₃. Resonances centered at 333.3, 480, 785.8, 838, and 1045.5 cm^-1 are from cubic As₂O₃, whereas resonances centered at 350, 490, and 808.5 cm^{-1 …}

Modeling Dc Power-Bus Structures With Vertical Discontinuities Using A Circuit Extraction Approach Based On A Mixed-Potential Integral Equation, Jun Fan, Hao Shi, Antonio Orlandi, James L. Knighten, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

The DC power-bus is a critical aspect in high-speed digital circuit designs. A circuit extraction approach based on a mixed-potential integral equation is presented herein to model arbitrary multilayer power-bus structures with vertical discontinuities that include decoupling capacitor interconnects. Green's functions in a stratified medium are used and the problem is formulated using a mixed-potential integral equation approach. The final matrix equation is not solved, rather, an equivalent circuit model is extracted from the first-principles formulation. Agreement between modeling and measurements is good, and the utility of the approach is demonstrated for DC power-bus design.

Self-Monitoring, Pseudo-Ductile, Hybrid Frp Reinforcement Rods For Concrete Applications, C. E. Bakis, Antonio Nanni, J. A. Terosky, S. W. Koehler

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The feasibility of hybrid -fiber-reinforced-polymer rods that demonstrate the important safety features of self-monitoring capability and pseudo-ductility is demonstrated. The rods are intended to be the basis of improved pultruded reinforcements for concrete or other civil applications where safety is of critical importance. The lowest elongation fiber in the seven rods investigated is carbon, which by virtue of its piezo resistivity allows the monitoring of deformation and fracture throughout an entire rod with simple electronic equipment. Resistance measurements obtained during quasi-static tests clearly reveal failure of the carbon fibers. Following this easily detected event, higher loads can be safely sustained …

Characterization Of Frp Rods As Near-Surface Mounted Reinforcement, Laura De Lorenzis, Antonio Nanni

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The use of near surface mounted (NSM) fiber-reinforced polymer (FRP) rods is a promising technology for increasing flexural and shear strength of deficient reinforced concrete (RC) members. As this technology emerges, the structural behavior of RC elements strengthened with NSM FRP rods needs to be fully characterized. Given the variability of material properties and groove geometry, this requires that the tensile properties of the FRP rod and the mechanics of load transfer between NSM FRP rods and concrete be investigated. Tensile and bond tests on commercially available carbon FRP deformed rods for application as NSM reinforcement were carried out using …

Countermeasures For Fatal Crashes On Two-Lane Rural Roads, Kenneth R. Agent, Jerry G. Pigman, Nikiforos Stamatiadis

Kentucky Transportation Center Research Report

In the first phase of this study, characteristics of crashes on two-lane rural roads were summarized and compared to all crashes. Also, one-mile sections having high crash rates were identified. In this phase of the study, a detailed analysis was conducted for a random sample of 150 fatal crashes which occurred on a two-lane rural road. Recommendations were made for countermeasures to reduce the number and severity of crashes on this type of roadway. The potential effectiveness of these countermeasures in preventing the crashes or reducing their severity was evaluated.

Crashes were selected from the years of 1996 through 1998. …

Molecular Simulation Of Adsorption: Gibbs Dividing Surface And Comparison With Experiment, Orhan Talu, Alan L. Myers

Chemical & Biomedical Engineering Faculty Publications

At low temperature near the normal boiling point, computer simulations of adsorption of gases can be compared directly with experiment. However, for adsorptive gas separations in which the gas is adsorbed near or above its critical temperature, absolute simulation variables must be converted to excess variables for comparison with experiment. The conversion of absolute to excess variables requires the helium pore volume of the adsorbent. Lennard-Jones potential parameters for helium gas molecules interacting with the oxygen atoms of silicalite are ε/k = 28.0 K and σ = 2.952 Å. The helium pore volume of silicalite is 0.175 cm …

Software Engineering Metrics For Cots-Based Systems, Sahra Sedigh, Arif Ghafoor, Raymond A. Paul

Electrical and Computer Engineering Faculty Research & Creative Works

The paradigm shift to commercial off-the-shelf components appears inevitable, necessitating drastic changes to current software development and business practices. Quality and risk concerns currently limit the application of COTS based system design to noncritical applications. New approaches to quality and risk management will be needed to handle the growth of CBSs. Our metrics based approach and software engineering metrics can aid developers and managers in analyzing the return on investment in quality improvement initiatives for CBSs. These metrics also facilitate the modeling of cost and quality, although we need more complex models to capture the intricate relationships between cost and …

Particle Motion In Packed/Ebullated Beds By Ct And Carpt, Jinwen Chen, Novica Rados, Muthanna H. Al-Dahhan, Milorad P. Duduković, Duyen Nguyen, Krishniah Parimi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Computed Tomography (CT) and Computer-Automated Radioactive Particle Tracking (CARPT) Were Used to Study the Gas Distribution and Incipient Particle Motion in a Packed/ebullated Bed in Which Gas and Liquid Are in Cocurrent Upflow. CT Scans Were Performed to Evaluate the Gas-Liquid Distributor and Gas Sparger for the Experiments, using a Perforated Plate Gas-Liquid Distributor (With 96 1-Mm Holes, Open Area of 0.1%) and a Gas Sparger (Cross-Shaped, with 16 3-Mm Holes), the Cross-Sectional Gas Holdup Distribution in the Packed/ebullated Bed Was Relatively Uniform, with Gas Holdup of About 0.11 in the Center and 0.09 Near the Wall of the Bed …