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2007

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Articles 1501 - 1530 of 3831

Full-Text Articles in Engineering

A Prioritization Process For Access Management Implementation In Utah, Kordel T. Braley May 2007

A Prioritization Process For Access Management Implementation In Utah, Kordel T. Braley

Theses and Dissertations

Appropriate access management techniques can improve the safety and efficiency of arterial roads. In order to determine which roads can most benefit by the implementation of access management techniques, a prioritization process was developed to recommend various access management treatments such as limiting access points, installing raised medians, and ensuring adequate signal spacing along corridors. To serve as the basis for the performance index, a database was created including identifying features, characteristics, and crash history for 175 arterial road segments on Utah state routes. Stepwise linear regression was applied to the data collected to determine which characteristics of the roads …


Software Development For Mechatronics Systems: Simulation Of Multiple Uav Navigation And Device Driver Interface For The Q4 Data Acquisition Card, Ninad Pradhan May 2007

Software Development For Mechatronics Systems: Simulation Of Multiple Uav Navigation And Device Driver Interface For The Q4 Data Acquisition Card, Ninad Pradhan

All Theses

Mechatronics systems are often a close interleaving of different aspects of hardware, software, control and mechanical design. Two such aspects are delved into in greater detail for this thesis, both related to software development.
Simulations are used to know the practical conditions under which a control design is effective. The system simulated in this case was a multiple vehicle system, where the vehicles navigated from source to a destination configuration avoiding two different kinds of obstacles.
Post simulation, a system is implemented using hardware and tested using an experimental setup. Data Acquisition Boards such as the Quanser Q4 are used …


Spatial Sensors For Quantitative Assessment Of Retrieved Arthroplasty Bearings, Melinda Harman May 2007

Spatial Sensors For Quantitative Assessment Of Retrieved Arthroplasty Bearings, Melinda Harman

All Dissertations

Evaluation of retrieved joint arthroplasty bearings provides unique evidence related to the physiological environment in which bearing materials are expected to perform. This dissertation describes the development of novel spatial sensors and measurement strategies for standardized, quantitative assessments of arthroplasty bearings, including total knee replacements, unicompartmental knee replacements, and total hip replacements. The approach is to assess bearings that endured a finite duration of function in patients, with particular emphasis on expanding our understanding of the biomechanical conditions specific to bearing function and wear in the physiological environment. Several quantifiable parameters are identified that prove comparable to pre-clinical in vitro …


Evaluation And Installation Guidelines For Advance Warning Signal Systems In Utah, Aaron Paul Jensen May 2007

Evaluation And Installation Guidelines For Advance Warning Signal Systems In Utah, Aaron Paul Jensen

Theses and Dissertations

Advance warning signals (AWS) provide information warning drivers in advance of the end-of-green phase for an approaching signalized intersection. The purpose of this research was to develop guidelines for the placement of AWS in Utah, both conditions to evaluate the need for AWS installation and guidelines for the AWS system design. The conditions were based on literature of other transportation agencies that had similar AWS systems and were developed using the Policy Delphi method. The Policy Delphi method is the development of a specific policy area through the means of discussion by a committee of experts correlating views and information …


Viability, Functionality, And Genetic Assessment Of Cells After Laser Guidance, Tabitha Rosenbalm May 2007

Viability, Functionality, And Genetic Assessment Of Cells After Laser Guidance, Tabitha Rosenbalm

All Theses

We systematically vary the controllable laser parameters, namely, wavelength, intensity, and exposure time of the laser on single cells to clearly establish laser parameters that allow negligible cell damage with significant cellular position control. To accomplish this goal, embryonic day 7 (E7) chick forebrains neurons were cultured with control and test cells selected one hour after seeding to allow attachment, at which time test cells were subjected to the laser. Cells were imaged at 4, 12, 24, and 36 hours after laser exposure to evaluate viability and functionality by using the Live/Dead Viability Cytotoxicity Kit (Molecular Probes L3224) and measuring …


System For And Method Of Investigating The Exact Same Point On A Sample Substrate With Multiple Wavelengths, Galen L. Pfeiffer, Martin M. Liphardt, Blaine D. Johs, Craig M. Herzinger, Christopher A. Goeden, Ping He, John A. Woollam, James D. Welch May 2007

System For And Method Of Investigating The Exact Same Point On A Sample Substrate With Multiple Wavelengths, Galen L. Pfeiffer, Martin M. Liphardt, Blaine D. Johs, Craig M. Herzinger, Christopher A. Goeden, Ping He, John A. Woollam, James D. Welch

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are system for and method of analyzing a sample at substantially the exact same small spot point on a sample with a plurality of wavelengths.


Order-Disorder Transformations In Sm–Co And Sm–Co–Zrc Systems With 2-17 Stoichiometry, Y.Y. Kostogorova-Beller, Jeffrey E. Shield, Matthew J. Kramer May 2007

Order-Disorder Transformations In Sm–Co And Sm–Co–Zrc Systems With 2-17 Stoichiometry, Y.Y. Kostogorova-Beller, Jeffrey E. Shield, Matthew J. Kramer

Materials Research Science and Engineering Center: Faculty Publications

This work investigates the order-disorder transformations utilizing time-resolved x-ray diffraction at the Advanced Photon Source. The metastable phases that can form during the order-disorder transformations in the Sm–Co intermetallics have the potential to produce materials with enhanced permanent magnetic properties. The high-temperature experiments transformed the disordered alloys with the TbCu7-type structure obtained by rapid solidification into the mixture of the hexagonal and rhombohedral ordered structures at 1375 K. The ordering process and the role of the ZrC alloying on the phase formation and ordering transformations were examined. The results showed the formation of shoulders of the fundamental peaks …


The Emerging Small Satellite Industry And Opportunities For Education, Robert J. Twiggs May 2007

The Emerging Small Satellite Industry And Opportunities For Education, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs titled "The Emerging Small Satellite Industry and Opportunities for Education" from May 3, 2007.


Evaluating The Impacts Of Accelerated Incident Clearance Tools And Strategies By Harnessing The Power Of Microscopic Traffic Simulation , Ryan Fries May 2007

Evaluating The Impacts Of Accelerated Incident Clearance Tools And Strategies By Harnessing The Power Of Microscopic Traffic Simulation , Ryan Fries

All Dissertations

Traffic incidents cause Americans delay, waste fuel, cause injuries, and create toxic emissions. Transportation professionals have implemented a variety of tools to manage these impacts and researchers have studied their effectiveness, illustrating a wide range between different tools and locations. To improve this state of knowledge, this dissertation sought to 1) identify prominent and effective incident management strategies, 2) model six selected incident management strategies within five highway corridors in South Carolina, and 3) apply benefit-cost analysis to evaluate the impact of various combinations of these strategies.
To meet these objectives, the author evaluated published literature of the selected strategies, …


System For And Method Of Investigating The Exact Same Point On A Sample Substrate With Multiple Wavelengths, Galen L. Pfeiffer, Martin M. Liphardt, Blaine D. Johs, Craig M. Herzinger, Christopher A. Goeden, Ping He, John A. Woollam, James D. Welch May 2007

System For And Method Of Investigating The Exact Same Point On A Sample Substrate With Multiple Wavelengths, Galen L. Pfeiffer, Martin M. Liphardt, Blaine D. Johs, Craig M. Herzinger, Christopher A. Goeden, Ping He, John A. Woollam, James D. Welch

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are system for and method of analyzing a sample at Substantially the exact same Small spot point on a sample with a plurality of wavelengths.


An Efficient Analysis Of Vertical Dipole Antennas Above A Lossy Half-Space , Yongfeng Huang May 2007

An Efficient Analysis Of Vertical Dipole Antennas Above A Lossy Half-Space , Yongfeng Huang

All Theses

The electromagnetic modeling of radiation by vertical dipole antennas above a lossy half-space has become an important subject due to many applications where these dipoles are involved. The modeling often encounters Sommerfeld-type integrals that are normally highly oscillatory with poor convergence. Recently, an efficient computation of the electric field radiated by an infinitesimal electric dipole above a lossy half-space has been reported, in which the Sommerfeld-type integrals are reduced to rapidly-converging integrals. Taking advantage of such efficiently-calculated electric field and using it as the Green's function, in this thesis, an electric field integral equation (EFIE) is formulated for the analysis …


Development Of Prediction Models To Measure Vendor Performance In Surveillance And Auditing Of Aircraft Maintenance, Nikhil Iyengar May 2007

Development Of Prediction Models To Measure Vendor Performance In Surveillance And Auditing Of Aircraft Maintenance, Nikhil Iyengar

All Dissertations

Elimination of aviation accidents is one of the primary goals of the Federal Aviation Administration (FAA) and the airline industry. A leading cause of aviation accidents is lack of oversight of various organizational issues, in particular, the organization's maintenance operation performance. The technologies used in the industry generate multiple risks, mostly from three domains: systems, hardware and people. Maintenance performance analyses identify the inherent risk in distributed, large-scale systems. Analysis of existing aviation maintenance data is a crucial step in meeting the aviation industry's need to improve aviation safety. Presently, we lack suitable tools to analyze large bodies of maintenance …


Multi-Stable Compliant Rolling-Contact Elements, Peter Andrew Halverson May 2007

Multi-Stable Compliant Rolling-Contact Elements, Peter Andrew Halverson

Theses and Dissertations

The purpose of this research is the development of design concepts and models of large-angle, compliant, multistable, revolute joints. This research presents evidence of the capability of these models and concepts by presenting a case study in which the miniaturization of revolute joints are examined. Previous attempts at multistable revolute joints can be categorized into two categories: compliant and non-compliant mechanisms. Non-compliant multistable revolute joints are typified by a combination of pin-in-slot joints, springs, and detents. Due to factors inherit in design, noncompliant joints often succumb to friction, wear, and undesirable motion, that leads to a decline in performance. Compliant …


Minimum Sample Size Needed To Construct Cushion Curves Based On The Stress-Energy Method, Patricia Marcondes May 2007

Minimum Sample Size Needed To Construct Cushion Curves Based On The Stress-Energy Method, Patricia Marcondes

All Theses

Cushion curves are graphical tools used by protective package designers to evaluate and choose foamed cushioning materials. Thousands of samples and hundreds of laboratory hours are needed to produce a full set of cushion curves according to the ASTM procedure D 1596. The stress-energy method considerably reduces the number of samples needed to construct cushion curves for closed-cell cushioning materials. Consequently the laboratory and data analysis time are reduced as well.
The stress-energy method was used to find the minimum sample size needed to construct cushion curves for closed-cell cushioning materials. A reference set of data collected for ARCEL Resin¨ …


Use Of The Clegg Impact Soil Tester To Access Rutting Susceptiblity Of Cement-Treated Base Material Under Early Trafficking, Garth B. Reese May 2007

Use Of The Clegg Impact Soil Tester To Access Rutting Susceptiblity Of Cement-Treated Base Material Under Early Trafficking, Garth B. Reese

Theses and Dissertations

In order to avoid the occurrence of early-age damage, cement-treated base (CTB) materials must be allowed to cure for a period of time before the pavement can be opened to traffic. Trafficking of a CTB before sufficient strength gain has occurred can lead to marring or rutting of the treated layer. The specific objectives of this research were to examine the correlation between Clegg impact values (CIVs) determined using a heavy Clegg impact soil tester and rut depths measured in newly constructed CTB and subsequently establish a threshold CIV at which rutting should not occur.The experimental work included field testing …


Kinetics Of Surface-Initiated Photoiniferter-Mediated Photopolymerization And Synthesis Of Stimuli-Responsive Polymer Brushes, Santosh Rahane May 2007

Kinetics Of Surface-Initiated Photoiniferter-Mediated Photopolymerization And Synthesis Of Stimuli-Responsive Polymer Brushes, Santosh Rahane

All Dissertations

The focus of this research is to understand the kinetic and mechanistic aspects of surface-initiated photoiniferter-mediated photopolymerization (SI-PMP) and exploit the robustness of SI-PMP to synthesize stimuli-responsive polymer brushes. The 'living' characteristics of dithiocarbamate-based photoiniferter-mediated photopolymerization are well documented. However, in this dissertation I show that the growth of poly(methyl methacrylate) (PMMA) brushes by SI-PMP is nonlinear, suggesting loss of radicals during SI-PMP and, in turn, non-living characteristics. Results from kinetic models in conjunction with experimental results suggest that irreversible bimolecular termination reactions are a primary culprit for the loss of radicals during SI-PMP. To overcome this problem of irreversible …


College Of Engineering Senior Design Competition Spring 2007, University Of Nevada, Las Vegas May 2007

College Of Engineering Senior Design Competition Spring 2007, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge.

The senior design competition helps to focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects …


Optimal Placement Of Metal Foils In Ultrasonic Consolidation Process, Raji Rexavier May 2007

Optimal Placement Of Metal Foils In Ultrasonic Consolidation Process, Raji Rexavier

All Theses

Ultrasonic Consolidation is a combination of additive and subtractive
manufacturing processes resulting in considerable material waste. This waste is a
function of the geometry of the part being manufactured and of the relative
placement of the layer with respect to the metal bands. Thus the waste may be
minimized by careful choice of the layer angle and offset from the original
position.
Previous work done in this field had developed an automated algorithm which
optimally places and orients the individual slices of the STL file of the artifact
being manufactured. However, the problem was solved on a 2-D scale and …


Development And In Vitro Examination Of Materials For Osseointegration, Sahil Jalota May 2007

Development And In Vitro Examination Of Materials For Osseointegration, Sahil Jalota

All Dissertations

Bone is a connective tissue with nanosized particles of carbonated apatitic calcium phosphate dispersed in a hydrated collagen matrix. With the ageing of the baby boomer population, an increasing number of people sustain bone fractures and defects. Hence, efforts are underway to develop materials to hasten the healing and repairing of such defects. These materials are termed as artificial bone substitutes.
This study represents innovative techniques for development of bone implant materials and improving the existing substitute materials. Emphasis was on three different kinds of materials: Metals (titanium and alloys), Ceramics (calcium phosphates), and Polymers (collagen). The bioactivity of titanium …


Volumetric Irrigation Water Pricing Considerations, Charles M. Burt May 2007

Volumetric Irrigation Water Pricing Considerations, Charles M. Burt

BioResource and Agricultural Engineering

Volumetric water pricing is a popular topic within donor agencies for irrigation project modernization and sustainability. Implementation of an effective pricing program is quite complex and requires consideration of physical modernization, fee structure, enforcement procedures, and the level of water delivery service. Variations of volumetric water pricing and allocation are discussed.


Ultrasonic Method For Aircraft Wake Vortex Detection, Rebecca J. Rodenhiser, William W. Durgin, Hamid Johari May 2007

Ultrasonic Method For Aircraft Wake Vortex Detection, Rebecca J. Rodenhiser, William W. Durgin, Hamid Johari

Office of the Provost Scholarship

This paper describes the experimental proof of concept study for an ultrasonic method of wake vortex detection. This new acoustic method uses travel time of acoustic pulses around a closed path to measure the net circulation within the acoustic path. In this application the closed path encloses the vorticity shed from one side of a Piper PA-28 aircraft wing. Magnitude and sign of circulation detected is comparable to the expected circulation generated by the Piper PA-28 test aircraft. This study demonstrates the validity of the acoustic method in detecting aircraft wake vortices. Further investigations and applications using this technique are …


Combinatorial Fusion Criteria For Robot Mapping, Damian M. Lyons, D. Frank Hsu, Qiang Ma, Liang Wang May 2007

Combinatorial Fusion Criteria For Robot Mapping, Damian M. Lyons, D. Frank Hsu, Qiang Ma, Liang Wang

Faculty Publications

We address the problem of sensor fusion for stereo and ultrasound depth measurements for map building for a robot operating in a cluttered environment. In such a situation it’s difficult to make useful and realistic assumpt ions about the sensor or environment statistics. Combinatorial Fusion Analysis is used to develop an approach to fusion with unknown sensor and environment statistics. A metric is proposed that shows when fusion from a set of fusion alternatives will produ ce a more accurate estimation of depth than either sonar or stereo alone and when not. The metric consists of two crit eria: (a) …


Acuta Enews May 2007, Vol. 36, No. 5 May 2007

Acuta Enews May 2007, Vol. 36, No. 5

ACUTA Newsletters

ln This lssue

Nominees for ACUTA Board of Directors 07-08

From ACUTA Headquarters ....................... Jeri A. Semer, CAE, ACUTA Executive Director

Staff Changes at ACUTA Headquarters

Tech Talk: Med Center Keeps Legacy Equipment Alive in New Network............ Kevin Tanzillo, Dux PR

Overheard on the Listserv: Panic Button Quick Fix ...... Rob McCray, Delaware Tech.& Comm. College

Board Report ............ Riny Ledgerwood, San Diego State Univ. ACUTA Sec./Treasurer

DC Update.......... Jeanne Jansenius, Sewanee, The University of the South

ATlS Releases Standard on Surveillance

Dues Notices Mailed May 1

Technology Policies and User Expectations Focus of 2007 Strategic Leadership Forum

Web Tip: …


Detecting Duplicates In Geoinformatics: From Intervals And Fuzzy Numbers To General Multi-D Uncertainty, Scott A. Starks, Luc Longpre, Roberto Araiza, Vladik Kreinovich, Hung T. Nguyen May 2007

Detecting Duplicates In Geoinformatics: From Intervals And Fuzzy Numbers To General Multi-D Uncertainty, Scott A. Starks, Luc Longpre, Roberto Araiza, Vladik Kreinovich, Hung T. Nguyen

Departmental Technical Reports (CS)

Geospatial databases generally consist of measurements related to points (or pixels in the case of raster data), lines, and polygons. In recent years, the size and complexity of these databases have increased significantly and they often contain duplicate records, i.e., two or more close records representing the same measurement result. In this paper, we address the problem of detecting duplicates in a database consisting of point measurements. As a test case, we use a database of measurements of anomalies in the Earth's gravity field that we have compiled.

In our previous papers, we have proposed a new fast (O(n log(n))) …


Towards Optimal Scheduling For Global Computing Under Probabilistic, Interval, And Fuzzy Uncertainty, With Potential Applications To Bioinformatics, Roberto Araiza, Michela Taufer, Ming-Ying Leung May 2007

Towards Optimal Scheduling For Global Computing Under Probabilistic, Interval, And Fuzzy Uncertainty, With Potential Applications To Bioinformatics, Roberto Araiza, Michela Taufer, Ming-Ying Leung

Departmental Technical Reports (CS)

In many practical situations, in particular in many bioinformatics problems, the amount of required computations is so huge that the only way to perform these computations in reasonable time is to distribute them between multiple processors. The more processors we engage, the faster the resulting computations; thus, in addition to processor exclusively dedicated to this job, systems often use idle time on other processors. The use of these otherwise engaged processors adds additional uncertainty to computations.

How should we schedule the computational tasks so as to achieve the best utilization of the computational resources? Because of the presence of uncertainty, …


On Probability Of Making A Given Decision: A Theoretically Justified Transition From Interval To Fuzzy Uncertainty, Van Nam Huynh, Yoshiteru Nakamori, Francois Modave May 2007

On Probability Of Making A Given Decision: A Theoretically Justified Transition From Interval To Fuzzy Uncertainty, Van Nam Huynh, Yoshiteru Nakamori, Francois Modave

Departmental Technical Reports (CS)

In practice, it is often necessary to make a decision under uncertainty.

In the case of interval uncertainty, for each alternative i, instead of the exact value vi of the objective function, we only have an interval of possible values. In this case, it is reasonable to assume that each value vi is uniformly distributed on the corresponding interval, and to take the probability that vi is the largest as the probability of selecting the i-th alternative.

In some practical situations, we have fuzzy uncertainty, i.e., for every alternative i, we have a fuzzy number describing the value of the …


Interval Computations As An Important Part Of Granular Computing: An Introduction, Vladik Kreinovich May 2007

Interval Computations As An Important Part Of Granular Computing: An Introduction, Vladik Kreinovich

Departmental Technical Reports (CS)

This chapter provides a general introduction to interval computations, especially to interval computations as an important part of granular computing. This introduction is aimed at researchers who would like to learn more - and eventually to use - the main ideas and techniques of granular computing.

We explain how intervals naturally appear in data processing, which techniques exist for processing intervals, and how these techniques have been historically developed.


When Are Two Wave Functions Distinguishable: A New Answer To Pauli's Question, With Potential Applications To Quantum Cosmology, Luc Longpre, Vladik Kreinovich May 2007

When Are Two Wave Functions Distinguishable: A New Answer To Pauli's Question, With Potential Applications To Quantum Cosmology, Luc Longpre, Vladik Kreinovich

Departmental Technical Reports (CS)

Traditional quantum mechanics (QM) predicts probabilities of different events. If we describe an elementary particle, then, experimentally, these probabilities mean that if we repeat the same measurement procedure with multiple particles in the same state, the resulting sequence of measurement results will be random w.r.t. the corresponding probability measure. In quantum cosmology, QM is used to describe the world as a whole; we have only one copy of the world, so multiple measurements are impossible. How to interpret these probabilities?

In this paper, we use the approach of the algorithmic information theory to come up with a reasonable interpretation. This …


On The Nature Of Over-Dispersion In Motor Vehicle Crash Prediction Models, Sudeshna Mitra, Simon Washington May 2007

On The Nature Of Over-Dispersion In Motor Vehicle Crash Prediction Models, Sudeshna Mitra, Simon Washington

Civil and Environmental Engineering

Statistical modeling of traffic crashes has been of interest to researchers for decades. Over the most recent decade many crash models have accounted for extra-variation in crash counts—variation over and above that accounted for by the Poisson density. The extra-variation – or dispersion – is theorized to capture unaccounted for variation in crashes across sites. The majority of studies have assumed fixed dispersion parameters in over-dispersed crash models—tantamount to assuming that unaccounted for variation is proportional to the expected crash count. Miaou and Lord [Miaou, S.P., Lord, D., 2003. Modeling traffic crash-flow relationships for intersections: dispersion parameter, functional form, and …


Chemical Composition Of Groundwater Hydrocarbon Mixtures Before And After Aerobic Biodegradation, Eileen Mick, Kevin Crossley, Yarrow Nelson May 2007

Chemical Composition Of Groundwater Hydrocarbon Mixtures Before And After Aerobic Biodegradation, Eileen Mick, Kevin Crossley, Yarrow Nelson

Civil and Environmental Engineering

No abstract provided.