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Articles 2551 - 2580 of 3831
Full-Text Articles in Engineering
Investigation Of Macrobending Losses Of Standard Single Mode Fiber With Small Bend Radii, Pengfei Wang, Qiang Wu, Gerald Farrell, Ginu Rajan, Thomas Freir, John Cassidy
Investigation Of Macrobending Losses Of Standard Single Mode Fiber With Small Bend Radii, Pengfei Wang, Qiang Wu, Gerald Farrell, Ginu Rajan, Thomas Freir, John Cassidy
Articles
An investigation of macrobending loss characteristics of a standard singlemode fiber (SMF28) for small bend radii is presented theoretically and experimentally, which includes the bend loss of the SMF28 with coating layers and the bare SMF28 after stripping the coating layers and chemical etching of partial cladding. The significant influence of reflection occurring at the interface between the cladding and coating layer or the cladding layer and air on the bend loss is investigated theoretically and experimentally.
Grounding Justice In Public Meeting Practice, Ted H. Grossardt, Keiron Bailey
Grounding Justice In Public Meeting Practice, Ted H. Grossardt, Keiron Bailey
Kentucky Transportation Center Faculty and Researcher Publications
John Rawl’s A Theory of Justice, and Justice as Fairness were originally intended to promote a political structure of liberal democracy. Taken together with Habermas’ idea of ’discourse ethics’, this work has constituted a fundamental aspect of the communicative approach in the planning discipline over the past 20 years. While their work is quite theoretical, it need not be detached from the reality of day- to-day practice. We agree with O’Neill that the work toward greater justice and fairness is eminently practical, and so should derive from their work. In particular, we are interested in advancing justice/fairness in the arena …
Culture, Justice And The Arnstein Gap: The Impact Of Structured Public Involvement On U.S. Transportation Infrastructure Planning And Design, Keiron Bailey, Ted H. Grossardt
Culture, Justice And The Arnstein Gap: The Impact Of Structured Public Involvement On U.S. Transportation Infrastructure Planning And Design, Keiron Bailey, Ted H. Grossardt
Kentucky Transportation Center Faculty and Researcher Publications
Enormous quantities of public money are spent on transportation infrastructure (TI). According to the Bureau of Transportation Statistics this infrastructure spend in the U.S. amounted to almost $90 billion in 2001. In most political spheres, when public money is spent, the public demands a measure of accountability. The dimensions of this accountability depend on the character of the political system that funds TI. In most participatory democracies, ultimate accountability is exercised through a balloting system that ensures elected officials represent, to some degree, stakeholder views and preferences. However, despite enormous expenditure of public monies on TI, this type of accountability …
Simulation And Development Of Nanoscale Deposition Techniques Using Kinetic Monte Carlo, Corey Clark
Simulation And Development Of Nanoscale Deposition Techniques Using Kinetic Monte Carlo, Corey Clark
Electrical Engineering Dissertations - Archive
Modeling of deposition processes has become of extreme importance due to the small scale of devices and features as well as the reduction of time to market required by industry. Current modeling procedures have focused on individual aspects of growth as well as made assumptions that cause simplification of the problem to the point the models usefulness is limited. The Kinetic Monte Carlo (KMC) model developed in this work combines rate transitions that have been commonly found in KMC simulation along with energy density equations that help explain the transitions and formations of island in alloy deposition. Specifically the model …
Acuta Enews January 2007, Vol. 36, No. 1
Acuta Enews January 2007, Vol. 36, No. 1
ACUTA Newsletters
In This Issue
From ACUTA Headquarters........... Jeri A. Semer, CAE, ACUTA Executive Director
Centrex Conversion to PBX.............. Ron Walczak, Walczak Technology Consultants
Tech Talk: Duduplication Reduces Storage Needs............. Kevin Tanzillo, Dux PR
DC Update............... Jeanne Jansenius, Sewanee, The University of the South
ACUTA Alert: Federal Rules Governing Destruction of Electronically Stored Information
FYI: Useful Information from the Campus.............. Student Monitor
Setting Priorities............... Geoff Tritsch, Vantage Technology Consulting Group
Web Tip: Members Post Job Openings........... Aaron Fuehrer, ACUTA Information Technology Manager
Board Report............... Riny Ledgerwood, San Diego State Univ. of Northern Iowa
Thanks to Sponsors for 2006
A Moment in Time: …
Campus Communications Systems: Converging Technologies, The Association For Communications Technology Professionals In Higher Education
Campus Communications Systems: Converging Technologies, The Association For Communications Technology Professionals In Higher Education
ACUTA: Other Publications
This book is a rewrite of Campus Telecommunications Systems: Managing Change, a book that was written by ACUTA in 1995. In the past decade, our industry has experienced a thousand-fold increase in data rates as we migrated from 10 megabit links (10 million bits per second) to 10 gigabit links (10 billion bits per second), we have seen the National Telecommunications Policy completely revamped; we have seen the combination of voice, data, and video onto one network; and we have seen many of our service providers merge into larger corporations able to offer more diverse services. When this book was …
Input-Output And Hybrid Techniques For Real-Time Prediction Of Delay And Maximum Queue Length At Signalized Intersections, Anuj Sharma, Darcy M. Bullock, James A. Bonneson
Input-Output And Hybrid Techniques For Real-Time Prediction Of Delay And Maximum Queue Length At Signalized Intersections, Anuj Sharma, Darcy M. Bullock, James A. Bonneson
Department of Civil and Environmental Engineering: Faculty Publications
Vehicle delay and queue length are quantitative measures of intersection performance. The technological advancement in the field of vehicle sensors and traffic controllers has reached a point where it has enabled efficient measurement of these performance measures. Two techniques are presented for real-time measurement of vehicle delay and queue length at a signalized Intersection, and these automated delay and queue estimates are compared with manually ground-truthed measurement. These techniques were evaluated at an instrumented intersection in Noblesville, Indiana. The root-mean-square error by both techniques was below 0.7 veh-s for-estimation of average delay and less than 0.15 vehicle for estimation of …
Nebraska Blueprint - Winter 2006-07
Nebraska Blueprint - Winter 2006-07
Nebraska Blueprint (Student Publication)
Table of Contents:
Good for Livestock, Good for the Earth By Michaela McBride
Ethanol Isn’t the Fuel of the Future Editorial by Aaron Holmberg
Ethanol: The Most Viable Alternative Fuel Editorial By Frank Pribyl
Wind Energy: A Global Perspective By Khoa Chu
UNL Should Embrace Energy- Effi cient Buildings By Leila Knowles and Jeremy Emerson
Biodiesel: A Viable Alternative By Brian Neilson
On the Road Again with BioWillie By Brian Neilson
Attitude Adjustment By Aaron Holmberg
Details And Description Of Operations Research, Paul Savory
Details And Description Of Operations Research, Paul Savory
Department of Industrial and Management Systems Engineering: Reports
The ambiguous term operations research was coined during World War II. A frequent substitute is management science. Operations research is a scientific approach to analyzing problems and making decisions. It uses mathematics and mathematical modeling on computers to forecast the implications of various choices and zero in on the best alternatives. This content paper provides an overview of operations research. It highlights operations research problems, methods for solving problems, different areas of operations research, and example problems.
Peer Review Of Teaching Project: Overview Newsletter, Paul Savory, Amy M. Goodburn, Amy Nelson Burnett
Peer Review Of Teaching Project: Overview Newsletter, Paul Savory, Amy M. Goodburn, Amy Nelson Burnett
Department of Industrial and Management Systems Engineering: Reports
The Peer Review of Teaching Project (PRTP) is a UNL campus program that supports teams of faculty in making visible the serious intellectual work of teaching. Begun in 1994, the project uses the same process one would use to explore a research question by having faculty inquire, analyze, and document their teaching practices and the resulting student learning and then make these results accessible for use, review, and assessment by one’s peers. The project consists of a first-year fellowship program and an advanced scholar program. Specific faculty outcomes from participating in the project include: (1) Reflecting upon, developing, and writing …
Pre/Post Assessment Of Abilities, Paul Savory
Pre/Post Assessment Of Abilities, Paul Savory
Department of Industrial and Management Systems Engineering: Instructional Materials
One approach to assess if students are learning in a course is to conduct a pre-test, post-test assessment of the course material. By comparing the two results, one can make an assessment of the knowledge learned in the course. For certain types of courses, it can be a challenge in defining an assessment instrument that measure student knowledge. This example is one I have developed for my IMSE 440/840 (Discrete Event Computer Simulation) course. Students are asked rate their ability for key course objectives defined on the course syllabus. I administer it on the first day of the course and …
A Bayesian Multilevel Modeling Approach For Data Query In Wireless Sensor Networks, Honggang Wang, Hua Fang, Kimberly A. Espy, Dongming Peng, Hamid Sharif
A Bayesian Multilevel Modeling Approach For Data Query In Wireless Sensor Networks, Honggang Wang, Hua Fang, Kimberly A. Espy, Dongming Peng, Hamid Sharif
Department of Electrical and Computer Engineering: Faculty Publications (to 2015)
In power-limited Wireless Sensor Network (WSN), it is important to reduce the communication load in order to achieve energy savings. This paper applies a novel statistic method to estimate the parameters based on the real-time data measured by local sensors. Instead of transmitting large real-time data, we proposed to transmit the small amount of dynamic parameters by exploiting both temporal and spatial correlation within and between sensor clusters. The temporal correlation is built on the level-1 Bayesian model at each sensor to predict local readings. Each local sensor transmits their local parameters learned from historical measurement data to their cluster …
A Computational Theory For The Generation Of Solutions During Early Conceptual Design, Cari R. Bryant
A Computational Theory For The Generation Of Solutions During Early Conceptual Design, Cari R. Bryant
Doctoral Dissertations
"Advancement in technology is usually made by building on previous experiences and learning from past successes and failures. However, knowledge transfer in the broad field of product design is often difficult to accomplish. Research has shown that successful component configurations, observed from existing products, can be dissected and stored for reuse; but few computational tools exist to assist designers during the conceptual phase of design. Many well-known manual methods (e.g. brainstorming, intrinsic and extrinsic searches, and morphological analysis) rely heavily on individual bias and experience and are often time intensive, laborious tasks that may not catch solutions that are functionally …
The Development Of Hybrid Intelligent Systems For Technical Analysis Based Equivolume Charting, Thira Chavarnakul
The Development Of Hybrid Intelligent Systems For Technical Analysis Based Equivolume Charting, Thira Chavarnakul
Doctoral Dissertations
"This dissertation proposes the development of a hybrid intelligent system applied to technical analysis based equivolume charting for stock trading. A Neuro-Fuzzy based Genetic Algorithms (NF-GA) system of the Volume Adjusted Moving Average (VAMA) membership functions is introduced to evaluate the effectiveness of using a hybrid intelligent system that integrates neural networks, fuzzy logic, and genetic algorithms techniques for increasing the efficiency of technical analysis based equivolume charting for trading stocks"--Introduction, page 1.
Nonlinear Optimization Approach For Upfc Power Flow Control And Voltage Security: Sufficient System Constraints For Optimality, Radha P. Kalyani
Nonlinear Optimization Approach For Upfc Power Flow Control And Voltage Security: Sufficient System Constraints For Optimality, Radha P. Kalyani
Doctoral Dissertations
"This dissertation provides a nonlinear optimization algorithm for the long term control of Unified Power Flow Controller (UPFC) to remove overloads and voltage violations by optimized control of power flows and voltages in the power network. It provides a control strategy for finding the long term control settings of one or more UPFCs by considering all the possible settings and all the (N-1) topologies of a power network. Also, a simple evolutionary algorithm (EA) has been proposed for the placement of more than one UPFC in large power systems"--Abstract, page iv.
Experimental And Analytical Evaluation Of Frp-Confined Large Size Reinforced Concrete Columns, Silvia Rocca
Experimental And Analytical Evaluation Of Frp-Confined Large Size Reinforced Concrete Columns, Silvia Rocca
Doctoral Dissertations
"Fiber Reinforced Polymer (FRP) jacketing of Reinforced Concrete (RC) columns, as a rapidly growing strengthening technique, requires appropriate design methods. However, the current available design guides are based on models, in their majority semi-empirical, and calibrated with small-scale plain concrete specimens. These models might not be reliable in predicting the strength and ductility enhancement sought through FRP-confinement in RC columns with geometric and material properties as found in practice. This dissertation presents the research conducted in three technical papers. In the first paper, the performance of 22 FRP-wrapped RC columns of medium- and large-scale is studied. The results of the …
Understanding Standing, Christopher Storey
Understanding Standing, Christopher Storey
Doctoral Dissertations
Research objectives. Psychophysical acceleration threshold is a tool for detecting deficits in dynamic postural control. Our lab has shown differences in the acceleration threshold among young adults, elderly adults, and elderly adults with diabetes. Electromyography, Semmes-Weinstein monofilaments, and hearing tests investigate the underlying physiological mechanisms for the detriments in postural control. Due to peri-sway perturbations, the motion of a person's sway affects the signal to noise ratio for perturbed stance. Since increases in sway range accompany postural instabilities, sway entrainment will allow us to investigate changes in acceleration threshold at different points in sway. The center of pressure, observed …
Evolvable Reconfigurable Hardware Framework For Edge Detection, Nader I. Rafla
Evolvable Reconfigurable Hardware Framework For Edge Detection, Nader I. Rafla
Electrical and Computer Engineering Faculty Publications and Presentations
Systems on Reconfigurable Chips contain rich resources of logic, memory, and processor cores on the same fabric. This platform is suitable for implementation of Evolvable Reconfigurable Hardware Architectures (ERHA). It is based on the idea of combining reconfigurable Field Programmable Gate Arrays (FPGA) along with genetic algorithms (GA) to perform the reconfiguration operation. This architecture is a suitable candidate for implementation of early-processing stage operators of image processing such as filtering and edge detection. However, there are still fundamental issues need to be solved regarding the on-chip reprogramming of the logic. This paper presents a framework for implementing an evolvable …
Novel Facial Image Recognition Techniques Employing Principal Component Analysis, Moataz Mahmoud Abdelwahab
Novel Facial Image Recognition Techniques Employing Principal Component Analysis, Moataz Mahmoud Abdelwahab
Electronic Theses and Dissertations
Recently, pattern recognition/classification has received considerable attention in diverse engineering fields such as biomedical imaging, speaker identification, fingerprint recognition, and face recognition, etc. This study contributes novel techniques for facial image recognition based on the Two dimensional principal component analysis in the transform domain. These algorithms reduce the storage requirements by an order of magnitude and the computational complexity by a factor of 2 while maintaining the excellent recognition accuracy of the recently reported methods. The proposed recognition systems employ different structures, multicriteria and multitransform. In addition, principal component analysis in the transform domain in conjunction with vector quantization is …
Modeling Free Chlorine And Chloramine Decay In A Pilot Distribution System, Jorge Miguel Arevalo
Modeling Free Chlorine And Chloramine Decay In A Pilot Distribution System, Jorge Miguel Arevalo
Electronic Theses and Dissertations
The purpose of this study was to identify the effect that water quality, pipe material, pipe size, flow conditions and the use of corrosion inhibitors would have on the rate of free chlorine and chloramine decay in distribution systems. Empirical models were developed to predict the disinfectant residual concentration with time based on the parameters that affected it. Different water treatment processes were used to treat groundwater and surface water to obtain 7 types of finished waters with a wide range of water quality characteristics. The groundwater was treated either by conventional treatment by aeration (G1) or softening (G2) or …
Soft Switching Multi-Resonant Forward Converter Dc To Dc Application For Communications Equipment, David Marlin Bills
Soft Switching Multi-Resonant Forward Converter Dc To Dc Application For Communications Equipment, David Marlin Bills
Electronic Theses and Dissertations
In the field of power electronics there is always a push to create smaller and more efficient power conversion systems. This push is driven by the industry that uses the power systems, and can be realized by new semiconductor devices or new techniques. This examination describes a novel technique for a small and highly efficient method of converting relatively high DC voltage to a very low voltage for use in the telecommunications industry. A modification to the standard Forward Resonant converter results in improvements in component stress, system efficiency, response time, and control circuitry. This examination describes background information needed …
Impact Of Zinc Orthophosphate Inhibitor On Distribution System Water Quality, Xiaotao Guan
Impact Of Zinc Orthophosphate Inhibitor On Distribution System Water Quality, Xiaotao Guan
Electronic Theses and Dissertations
This dissertation consists of four papers concerning impacts of zinc orthophosphate (ZOP) inhibitor on iron, copper and lead release in a changing water quality environment. The mechanism of zinc orthophosphate corrosion inhibition in drinking water municipal and home distribution systems and the role of zinc were investigated. Fourteen pilot distribution systems (PDSs) which were identical and consisted of increments of PVC, lined cast iron, unlined cast iron and galvanized steel pipes were used in this study. Changing quarterly blends of finished ground, surface and desalinated waters were fed into the pilot distribution systems over a one year period. Zinc orthophosphate …
Processing And Study Of Carbon Nanotube / Polymer Nanocomposites And Polymer Electrolyte Materials, Muthuraman Harish
Processing And Study Of Carbon Nanotube / Polymer Nanocomposites And Polymer Electrolyte Materials, Muthuraman Harish
Electronic Theses and Dissertations
The first part of the study deals with the preparation of carbon nanotube/polymer nanocomposite materials. The dispersion of multi-walled carbon nanotubes (MWNTs) using trifluoroacetic acid (TFA) as a co-solvent and its subsequent use in polymer nanocomposite fabrication is reported. The use of carbon nanotube/ polymer nanocomposite system for the fabrication of organic solar cells is also studied. TFA is a strong but volatile acid which is miscible with many commonly used organic solvents. Our study demonstrates that MWNTs can be effectively purified and readily dispersed in a range of organic solvents including dimethyl formamide (DMF), tetrahydrofuran (THF), and dichloromethane when …
Comparison Of Single Stage And Two Stage Stage Grid-Tie Inverters, Keith Mansfield
Comparison Of Single Stage And Two Stage Stage Grid-Tie Inverters, Keith Mansfield
Electronic Theses and Dissertations
This thesis compares two methods of designing grid-tie inverters. The first design topology is a traditional two stage approach consisting of an isolated DC-DC converter on the input followed by a high switching frequency SPWM (Sinusoidal Pulse Width Modulation) stage to produce the required low frequency sine wave output. The novel second design approach employs a similar DC-DC input stage capable of being modulated to provide a rectified sine wave output voltage/current waveform. This stage is followed by a simple low frequency switched Unfolding Stage to recreate the required sine wave output. Both of the above designs have advantages and …
Multisensor Fusion Remote Sensing Technology For Assessing Multitemporal Responses In Ecohydrological Systems, Ammarin Makkeasorn
Multisensor Fusion Remote Sensing Technology For Assessing Multitemporal Responses In Ecohydrological Systems, Ammarin Makkeasorn
Electronic Theses and Dissertations
Earth ecosystems and environment have been changing rapidly due to the advanced technologies and developments of humans. Impacts caused by human activities and developments are difficult to acquire for evaluations due to the rapid changes. Remote sensing (RS) technology has been implemented for environmental managements. A new and promising trend in remote sensing for environment is widely used to measure and monitor the earth environment and its changes. RS allows large-scaled measurements over a large region within a very short period of time. Continuous and repeatable measurements are the very indispensable features of RS. Soil moisture is a critical element …
Low Temperature Nitife Shape Memory Alloys: Actuator Engineering And Investigation Of Deformation Mechanisms Using In Situ Neutr, Vinu Krishnan
Low Temperature Nitife Shape Memory Alloys: Actuator Engineering And Investigation Of Deformation Mechanisms Using In Situ Neutr, Vinu Krishnan
Electronic Theses and Dissertations
Shape memory alloys are incorporated as actuator elements due to their inherent ability to sense a change in temperature and actuate against external loads by undergoing a shape change as a result of a temperature-induced phase transformation. The cubic so-called austenite to the trigonal so-called R-phase transformation in NiTiFe shape memory alloys offers a practical temperature range for actuator operation at low temperatures, as it exhibits a narrow temperature-hysteresis with a desirable fatigue response. Overall, this work is an investigation of selected science and engineering aspects of low temperature NiTiFe shape memory alloys. The scientific study was performed using in …
Vacancy Engineered Doped And Undoped Nanocrystalline Rare Earth Oxide Particles For High Temperature Oxidation Resistant Coating, Ranjith Thanneeru
Vacancy Engineered Doped And Undoped Nanocrystalline Rare Earth Oxide Particles For High Temperature Oxidation Resistant Coating, Ranjith Thanneeru
Electronic Theses and Dissertations
Rare earth oxides with trivalent lattice dopants have been of great interest to researchers in the recent years due to its potential applications in catalysis and high temperature protective coatings. The ability to store oxygen in rare earths is the basis for catalysis because of the ability to change valence states which causes the presence of intrinsic oxygen vacancies in the crystal lattice. Although, several doped-rare earth oxide systems in micron scale have been investigated, the doping effect in cerium oxide nanoparticles with well characterized particle size has not been studied. The doping of ceria at that small size can …
Infrared Antenna-Coupled Phased-Array, Christopher Middlebrook
Infrared Antenna-Coupled Phased-Array, Christopher Middlebrook
Electronic Theses and Dissertations
Phased-array antennas are commonplace in the radiofrequency portion of the electromagnetic spectrum. Exploitation of phasing effects between multiple antennas facilitates a wide range of applications, including synthetic-aperture radar, beam forming, and beam scanning. For the first time, the phased addition of multiple dipole antennas is demonstrated in the infrared, at a wavelength of 10.6 micrometers. Coplanar strip lines are used to interconnect the antennas, preserving the phase of the individual contributions. Several different proof-of-concept experiments are performed, using planar antennas fabricated with direct-write electron-beam lithography. Infrared-frequency currents from two dipole antennas are summed together at a common feedpoint and dissipated …
High-Speed Modelocked Semiconductor Lasers And Applications In Coherent Photonic Systems, Wangkuen Lee
High-Speed Modelocked Semiconductor Lasers And Applications In Coherent Photonic Systems, Wangkuen Lee
Electronic Theses and Dissertations
1.55-µm high-speed modelocked semiconductor lasers are theoretically and experimentally studied for various coherent photonic system applications. The modelocked semiconductor lasers (MSLs) are designed with high-speed (>5 GHz) external cavity configurations utilizing monolithic two-section curved semiconductor optical amplifiers. By exploiting the saturable absorber section of the monolithic device, passive or hybrid mode-locking techniques are used to generate short optical pulses with broadband optical frequency combs. Laser frequency stability is improved by applying the Pound-Drever-Hall (PDH) frequency stabilization technique to the MSLs. The improved laser performance after the frequency stabilization (a frequency drifting of less than 350 MHz), is extensively studied …
A Weighted Residual Parabolic Acceleration Time Integration Method For Problems In Structural Dynamics, Ali Abolmaali, S.H. Razavi, M. Ghassemieh
A Weighted Residual Parabolic Acceleration Time Integration Method For Problems In Structural Dynamics, Ali Abolmaali, S.H. Razavi, M. Ghassemieh
Civil Engineering Faculty Publications - Archive
In the proposed method, the variation of displacement in each time step is assumed to be a fourth order polynomial in time and its five unknown coefficients are calculated based on: two initial conditions from the previous time step; satisfying the equation of motion at both ends of the time step; and the zero weighted residual within the time step. This method is non-dissipative and its dispersion is considerably less than in other popular methods. The stability of the method shows that the critical time step is more than twice of that for the linear acceleration method and its convergence …