Engineering Commons^™

Incorporation Of Cerium And Neodymium In A Uranyl Hydroxide Solid, Chang-Soo Kim, David J. Wronkiewicz, R. J. Finch, E. C. Buck

Electrical and Computer Engineering Faculty Research & Creative Works

The migration behavior of radionuclides in a nuclear-waste repository will be influenced, in part, by their equilibrium solubilities in the presence of radionuclide-bearing solids and/or adsorption affinities as trace components onto the surfaces of solid host phases. Uranium phases that precipitate on the surface of altered spent nuclear fuel may thus influence the mobility of radionuclides released in the near-field environment, since by proximity, these will be the first phases that the radionuclides encounter following their release from the spent fuel matrix. We have evaluated the potential for incorporating radionuclides into crystalline compounds by precipitating uranyl phases from aqueous solutions …

A New Method For Suboptimal Control Of A Class Of Nonlinear Systems, Ming Xin, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, a new nonlinear control synthesis technique (θ - D approximation) is presented. This approach achieves suboptimal solutions to nonlinear optimal control problems in the sense that it solves the Hamilton-Jacobi-Bellman (HJB) equation approximately by adding perturbations to the cost function. By manipulating the perturbation terms both semi-globally asymptotic stability and suboptimality properties can be obtained. The convergence and stability proofs are given. This method overcomes the large control for large initial states problem that occurs in some other Taylor expansion based methods. It does not need time-consuming online computations like the state dependent Riccati equation (SDRE) technique. …

Modeling, Fabrication, And Optimization Of Niobium Cavities: Phase Ii Second Quarterly Report, Robert A. Schill Jr., Mohamed Trabia

Transmutation Sciences Materials (TRP)

Niobium cavities are important parts of the integrated NC/SC high-power linacs. Over the years, researchers in several countries have tested various cavity shapes. They concluded that elliptically shaped cells are the most appropriate shape for superconducting cavities. The need for very clean surfaces lead to the use of a buffered chemical polishing produce for surface cleaning to get good performance of the cavities. Up to this point, the second phase has resulted in the design of an experimental setup for the fluid flow experiment. Other experimental activities include the evaluation of a vacuum system are underway. Little reportable progress has …

A New Approach To Evaluate Fracture Strength Of Uv-Liga Fabricated Nickel Specimens, Catherine Oropeza

LSU Master's Theses

One of the major difficulties faced by MEMS researchers today is the lack of data regarding properties of electroplated metals or alloys at micro-levels as those produced by the LIGA and LIGA related process. These mechanical properties are not well known and they cannot be extrapolated from macro-scale data without experimental verification. This lack of technical information about microscale physical properties has affected the consistency and reliability of batch-fabricated components and leads to very low rates of successful fabrication. Therefore, this material issue is of vital importance to the development of LIGA technology and to its industrial applications. This thesis …

Inspector's Job Guide, Indiana Ltap

Indiana Local Technical Assistance Program (LTAP) Publications

These guidelines are intended to cover the very basic duties of inspection by reference to key activities which must be supplemented by reference to contract documents, specifications, special provisions, instructional manuals, and guidance by the project engineer.

Metal–Insulator–Semiconductor Electrostatics Of Carbon Nanotubes, Jing Guo, Sebastien Goasguen, Mark S. Lundstrom, Supriyo Datta

Department of Electrical and Computer Engineering Faculty Publications

Carbon nanotube metal-insulator-semiconductor capacitors are examined theoretically. For the densely packed array of nanotubes on a planar insulator, the capacitance per tube is reduced due to the screening of the charge on the gate plane by the neighboring nanotubes. In contrast to the silicon metal-oxide-semiconductor capacitors, the calculated C-VC-V curves reflect the local peaks of the one-dimensional density-of-states in the nanotube. This effect provides the possibility to use C-VC-V measurements to diagnose the electronic structures of nanotubes. Results of the electrostatic calculations can also be applied to estimate the upper-limit on-current of carbon nanotube field-effect transistors.

Circulatory Adjuncts: Newer Methods Of Cardiopulmonary Resuscitation, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Current standard CPR only provides about one fifth of normal forward blood flow and only about one quarter of the blood flow that is theoretically possible with advanced external techniques. Two such techniques are now approved as optional alternatives in resuscitation guidelines. This chapter reviews modern understanding of the physiology of blood flow during CPR and practical aspects of utilizing more advanced resuscitation methods. When properly performed these methods produce statistically significant increases in survival.

Performance Projections For Ballistic Carbon Nanotube Field-Effect Transistors, Jing Guo, Mark S. Lundstrom, Supriyo Datta

Department of Electrical and Computer Engineering Faculty Publications

The performance limits of carbon nanotube field-effect transistors (CNTFETs) are examined theoretically by extending a one-dimensional treatment used for silicon metal-oxide-semiconductor field-effect transistors (MOSFETs). Compared to ballistic MOSFETs, ballistic CNTFETs show similar I-VI-V characteristics but the channel conductance is quantized. For low-voltage, digital applications, the CNTFET with a planar gate geometry provides an on-current that is comparable to that expected for a ballistic MOSFET. Significantly better performance, however, could be achieved with high gate capacitance structures. Because the computed performance limits greatly exceed the performance of recently reported CNTFETs, there is considerable opportunity for progress in device performance.

A Drift-Diffusion Equation For Ballistic Transport In Nanoscale Metal-Oxide-Semiconductor Field Effect Transistors, Jung-Hoon Rhew, Mark S. Lundstrom

Department of Electrical and Computer Engineering Faculty Publications

The performance limits of carbon nanotube field-effect transistors ~CNTFETs! are examined theoretically by extending a one-dimensional treatment used for silicon metal–oxide– semiconductor field-effect transistors ~MOSFETs!. Compared to ballistic MOSFETs, ballistic CNTFETs show similar I –V characteristics but the channel conductance is quantized. For low-voltage, digital applications, the CNTFET with a planar gate geometry provides an on-current that is comparable to that expected for a ballistic MOSFET. Significantly better performance, however, could be achieved with high gate capacitance structures. Because the computed performance limits greatly exceed the performance of recently reported CNTFETs, there is considerable opportunity for progress in device performance.

Simulating Quantum Transport In Nanoscale Mosfets: Real Vs. Mode Space Approaches, Rajesh Venugopal, Z. Ren, Supriyo Datta, Mark S. Lundstrom, D. Jovanovic

Department of Electrical and Computer Engineering Faculty Publications

The performance limits of carbon nanotube field-effect transistors (CNTFETs) are examined theoretically by extending a one-dimensional treatment used for silicon metal–oxide–semiconductor field-effect transistors (MOSFETs). Compared to ballistic MOSFETs, ballistic CNTFETs show similar I–VI–V characteristics but the channel conductance is quantized. For low-voltage, digital applications, the CNTFET with a planar gate geometry provides an on-current that is comparable to that expected for a ballistic MOSFET. Significantly better performance, however, could be achieved with high gate capacitance structures. Because the computed performance limits greatly exceed the performance of recently reported CNTFETs, there is considerable opportunity for progress in device performance.

Optimum Compression To Ventilation Ratios In Cpr Under Realistic, Practical Conditions: A Physiological And Mathematical Analysis, Charles F. Babbs, Karl B. Kern

Weldon School of Biomedical Engineering Faculty Publications

Objective: To develop and evaluate a practical formula for the optimum ratio of compressions to ventilations in CPR. The optimum value of a parameter is that for which a desired result is maximized. Here the desired result is assumed to be either oxygen delivery to peripheral tissues or a combination of oxygen delivery and waste product removal. Method: Equations describing oxygen delivery and blood flow during CPR as functions of the number of compressions and the number of ventilations delivered over time were developed from principles of classical physiology. These equations were solved explicitly in terms of the compression/ventilation ratio …

Counting Device Selection And Reliability: Synthesis Study, Srinivas Peeta, Pengchang Zhang

JTRP Technical Reports

Accuracy in traffic data detection is important for transportation operations and planning. Currently, inductive loop detectors are the most commonly used traffic counting devices in the field. New technologies are being developed to meet growing data counting and traffic surveillance needs. They include passive infrared, active infrared, passive magnetic, Doppler microwave, radar, passive acoustic, pulse and Doppler ultrasonic and video image processor. However, the relatively recent, but widespread, emergence of these technologies and the consequent sparseness in information on their performance characteristics preclude traffic agencies from making informed choices in the selection of traffic counting devices. This study performs a …

Fatigue Behavior Of Beam Diaphragm Connections With Intermittent Fillet Welds: Part Ii, Brittle Fracture Examination Of The I-64 Blue River Bridge, Mark D. Bowman

JTRP Technical Reports

This report is the second of a two-part, three volume final report presenting the findings of the research work that was undertaken to evaluate the behavior of Indiana highway bridges with diaphragm members welded directly to the web of the primary beams and girders. Fatigue cracks have been observed at several bridges that utilize the welded diaphragm connection. The seriousness of the cracking and the corresponding potential risk on the integrity of the bridge superstructure were assessed. Inspection and repair guidelines for bridges with the welded diaphragm connections were also developed as part of the research effort. This volume presents …

Updating Procedures To Estimate And Forecast Vehicle-Miles Traveled, Jon D. Fricker, Raymond K. Kumapley

JTRP Technical Reports

Procedures developed for the estimation of Vehicle-Miles of Travel (VMT) have been fraught with problems of inaccuracy. Emphasis on environmental issues (air quality), as mandated by current regulations (CAAA, ISTEA-91, and TEA 21), requires State DOTs to accurately estimate travel on their highway infrastructure. The Federal Highway Administration (FHWA) has developed, and subsequently modified, the Highway Performance Monitoring System (HPMS) to assist in data collection and reporting. INDOT currently estimates VMT by a method that closely follows the HPMS method. Roads that are not on the state highway system (minor collectors, urban collectors and local) are not represented in the …

Using Commercial Finite Element Code Called Abaqus In Modeling Hybrid Constrained Layers Damping Beam Structure And Quantitative Determination Of The Stability Of Implant-Bone Interface Using Resonance Frequency Analysis, Daniel Delgado Jr.

Theses and Dissertations - UTB/UTPA

In Chapter 1, it has been demonstrated that the damping treatments for beam and plate structures are effective, and the vibrational behaviors of the systems considered are influenced by many geometrical and material parameters. This has led to an interest in developing advanced “intelligent” structures. In the past, passive and active damping mechanisms have been used to reduce vibration. The uses of passive constrained layers are limited, but it has dissipative qualities for all the modes of the structure; and the uses of active constrained layers are limited to a single mode control. Recent published papers, many have suggested that …

Defining Benthic Organism Exposure: Bioavailability And Effects Of Non-Polar Organics, Marc Samuel Greenberg

Browse all Theses and Dissertations

Laboratory and field tests were conducted to evaluate the hypothesis that factors such as the total organic carbon (TOC) contents and groundwater-surface water interactions (GSI) in the sediments can affect chemical desorption, bioavailability and benthic organism exposure. Laboratory studies were conducted with the polycyclic aromatic hydrocarbon fluoranthene (FLU) and the herbicide trifluralin (TF). Toxicokinetic parameters were determined for Lumbriculus variegatus and Hyalella azteca in water-only exposures to 0, 5, 20 and 50 µg/L of the compounds and bioaccumulation was measured during exposures to 0, 100 and 200 mg/kg of FLU and TF spiked onto sediments from Lakes Erie and Huron. …

Influence Of Curing Conditions On Strength Properties And Maturity Development Of Concrete, Scott Andrew Newbolds, Jan Olek

JTRP Technical Reports

In this study, the results of both laboratory studies and a field study, conducted to evaluate the effects of different curing conditions on the strength properties and maturity development of pavement concrete, are presented. Further, a laboratory study was performed to evaluate the maturity concept in relation to the degree of hydration of cement. Concrete specimens, beams and cylinders, were prepared in the field study. The specimens in the field were cured in one of four curing conditions: lime bath, sandpit, air, or by temperature match curing. Specimens were tested for flexural strength and compressive strength, respectively. The temperature of …

Scour Monitoring Of Indiana Streams, Dennis A. Lyn, Thomas J. Cooper, Yong-Kon Yi, Rahul N. Sinha, A. Ramachandra Rao

JTRP Technical Reports

The project examines the survivability and reliability of fixed-in-place continuous scour monitors for possible use in Indiana streams. The report considers primarily the experience with a sonar device at the US52 crossing of the Wabash River. Although very large flow events did not occur over the project period, the device has survived a number of smaller events, and has operated continuously without failure due to physical damage. Further, the data obtained, after appropriate processing, were examined for their credibility in terms of their correlation with a hydrologic parameter, the stage. A reasonably strong correlation was found, suggesting that the recorded …

Sign Retroreflectivity Study, Austin Lyons Bischoff, Darcy M. Bullock

JTRP Technical Reports

Signing is a big yearly cost to state DOT’s in sign maintenance and replacement costs. In 2001 the Indiana Department of Transportation (INDOT) replaced 14,930 signs at a cost of $1,067,931 and did maintenance work on 34,084 signs at a cost of $2,136,076. Recently, guidelines have been proposed by the Federal Highway Administration (FHWA) for minimum retroreflectivity of traffic signs for state, county, and city roads in the United States. The purpose of this study was to evaluate if the majority of the signs currently used by INDOT will meet the new minimum requirements proposed by the FHWA. In addition, …

Study Of The Performance Of Acoustic Barriers For Indiana Toll Roads, Sanghoon Suh, Luc Mongeau, J. Stuart Bolton

JTRP Technical Reports

The purpose of this study was to optimize the geometry and the acoustic properties of sound barriers for traffic noise applications. The approach consisted of developing and validating boundary element predictive models, which were subsequently exercised in order to refine the barrier characteristic and determine optimized configurations. The simple geometry of a circular disk was chosen to validate the boundary element model in the first part of this work. Experiments were performed in an anechoic chamber to validate the numerical model. Complex barrier geometries were then investigated to study the effects of geometry on sound barrier performance. Boundary element models …

The Examination Of Infra-Red Techniques For Inspection Of Steel Structures I & Ii, Vachirapun Trakulyingyong, Mark D. Bowman

JTRP Technical Reports

Infra-red thermography systems that have been developed over the last few years offer great potential to locate and discover flaws in steel highway bridge structures at a relatively early stage in their development. Under ideal conditions, the use of infra-red instrumentation should allow bridge inspection personnel to rapidly scan the structure and determine if a potential structural problem has developed. If a problem spot is located by the infra-red camera, then the trouble spot can be examined carefully to determine the need for corrective maintenance. The primary purpose of this research study is to evaluate the accuracy and reliability of …

Validation, Calibration, And Evaluation Of Its Technologies On The Borman Corridor, Srinivas Peeta, Pengchang Zhang, Raghubhushan K. Pasupathy

JTRP Technical Reports

This study develops an Internet-based remote on-line traffic control architecture for route guidance in large-scale traffic systems equipped with advanced information systems and sensors. It also proposes to use the Beowulf Cluster paradigm as an economical, flexible, and customizable computing architecture to generate supercomputing capabilities within the control architecture. The Beowulf Cluster provides the enabling environment to execute and coordinate the activities of the various modules that address real-time network route guidance, data transmission, calibration and fault tolerance. In the context of large-scale traffic systems, a Beowulf Cluster can be configured in centralized as well as decentralized on-line control architectures …

Worker Exposure To Airborne Contaminates When Using Waste Foundry Sand In The Construction Of Road Embankments, Waseem Afzal, Robert Bertram Jacko

JTRP Technical Reports

A section of road was constructed in Northeastern Indiana in the summer of 1996 using waste foundry sand as the embankment construction material. Initial testing on the waste sand had determined no detrimental health effects. However, it was observed during construction that once the sand had dried, tire-road interaction raised copious clouds of black dust. This led to worker concern regarding airborne silica and silicosis. This study aimed at determining whether the threat of overexposure to airborne crystalline silica existed in regard to Occupation Health and Safety Administration’s (OSHA) Permissible Exposure Limit (PEL). Experiments carried out at the Auburn Foundry …

Web-Based Distance Instructional Partnership For Maritime Technology Of Pacific Rim Countries, Chun-Mei Shieh

Dissertations and Theses @ UNI

The prime purpose of this study was to identify and determine the attitudes and intentions of the faculty members in the field of marine technology education in Taiwan and Australia regarding adopting Web-based distance education. A secondary purpose was to develop guidelines for a program in preparation for implementing Web-based distance education for faculty members in Taiwan.

Five groups in the field of marine technology composed the research population for this study. They are the faculty members in Taiwan in nine vocational high schools, two junior colleges, the National Kaohsiung Institute Marine Technology (NKIMT), and the National Taiwan Ocean University …

Symmetrically Coated Pellicle Beam Splitters For Dual Quarter-Wave Retardation In Reflection And Transmission, Rasheed M.A. Azzam, Fadi A. Mahmoud

Electrical Engineering Faculty Publications

A trilayer pellicle that consists of a high-index center layer that is symmetrically coated on both sides by a low-index film can be designed to produce differential reflection and transmission phase shifts of ∓90° at oblique incidence and equal throughput for the p and the s polarizations. Such a device splits a beam of incident linearly polarized light into two orthogonal circularly polarized components that travel in well-separated angular directions. Examples of infrared dual quarter-wave retarders that use a symmetrically coated Ge pellicle at 77° angle of incidence are presented. A 50–50% splitter requires a symmetric pellicle with at least …

Angular Range For Reflection Of P-Polarized Light At The Surface Of An Absorbing Medium With Reflectance Below That At Normal Incidence, R. M.A. Azzam, Ericson E. Ugbo

Electrical Engineering Faculty Publications

The range of incidence angle, 0 < φ < φ_e, over which p-polarized light is reflected at interfaces between transparent and absorbing media with reflectance below that at normal incidence is determined. Contours of constant φ_e in the complex plane of the relative dielectric constant ε are presented. A method for determining the real and imaginary parts of the complex refractive index, ε^1/2 = n + jk, which is based on measuring φ_e and the pseudo-Brewster angle φ_pB, is viable in the domain of fractional optical constants, n, k < 1.

Assessment Of Slip Severity Among Different Age Groups, Thurmon E. Lockhart, Jeffrey C. Woldstad, James L. Smith

Department of Industrial and Management Systems Engineering: Faculty Publications

A laboratory study utilizing new techniques for assessing slip severity was conducted to investigate the process of inadvertent slips and falls among different age groups. Forty-two subjects from three age groups (young adults, middle-aged, and the elderly) walked on a rectangular track at a self-determined pace. Without the subjects’ awareness, a slippery floor surface was placed on the track over a force-measuring platform. The results indicated that elderly adults’ friction demand (RCOF) was not significantly different from the young and middle-aged adults. The older adults, however, fell more often than the other age groups. Fall recovery threshold (FRT) measures indicated …

A Simulation Based Experiment For Comparing Amhs Performance In A Semiconductor Fabrication Facility, Gerald Mackulak, Paul Savory

Department of Industrial and Management Systems Engineering: Faculty Publications

As the cost and complexity of constructing a semiconductor fabrication facility increases, responsive tools are needed for designing and planning its operations. Discrete-event simulation paired with design of experiments is an effective combination. This article demonstrates how simulation in combination with design of experiments is used to compare the intrabay layout of two automated material handling systems. The difference in stocker robot utilization, number of vehicle moves per hour, and average delivery time for the two intrabay layouts will be compared using a fractional factorial experimental design. The study demonstrates that the distributed storage option is preferable for maximizing manufacturing …

An Airborne Low-Cost Sar For Remote Sensing: Hardware Design And Development, Ram Narayanan, Paul C. Cantu, Xiaojian Xu

Department of Electrical and Computer Engineering: Faculty Publications

An airborne low-cost synthetic aperture radar (SAR) is under development at the University of Nebraska-Lincoln. The SAR system is an X-band, stepped-chirp frequency modulation (SCFM) radar system. One of its unique features is that the waveform generation consists of a timing-controlled D/A converter and VCO arrangement to synthesize the SCFM signal, whereby allowing for less design complexity and a much lower overall system cost. In this paper, we present a brief description of the system and some computer simulation results.

Shape-Based Change Detection And Information Mining In Remote Sensing, Jiang Li, Ram M. Narayanan

Department of Electrical and Computer Engineering: Faculty Publications

Change detection is an important application of remote sensing. This paper presents our approach to retrieve and represent interesting shapes in the remotely sensed imagery using supervised classification, edge detection, and polygonal approximation techniques, and to compare the shape similarity by a computationally efficient metric. The experiments were conducted on a time series of calibrated and registered Landsat MSS images, covering the scene of the lakes at the western Nebraska. The results show the effectiveness of the shape-based change detection approach, which is potentially useful for specific applications such as the study of the lake change response to short or …