Engineering Commons^™

Water Conservation Technologies, Liam Mccarton

Articles

Given the increasing incidence of serious flooding in Europe in recent years it might seem odd to be addressing the problem of water conservation. However, recent economic prosperity has led to an increased per capita use of water for domestic and industrial use. The traditional approach to meeting increased demand is to augment supply. However, mobilising new resources involves ever higher costs. Allied to this is the concept of sustainability, which can be defined as ‘development that meets the needs of the present without compromising the ability of future generations to meet their own needs’. An important consideration of …

Roadway Lighting And Driver Safety, Eric R. Green, Kenneth R. Agent, Monica L. Barrett, Jerry G. Pigman

Kentucky Transportation Center Research Report

The objectives of this project were to: a) analyze the safety benefits associated with roadway lighting; b) determine the design of the lighting installation necessary to provide an adequate level of lighting; c) investigate how lighting affects the driver and the roadway’s surrounding environment; d) review the economic correlation between effective lighting and cost savings for the State; e) provide input for updating the current section on street and highway lighting in the Traffic Guidance Manual; and f) analyze crash data to identify nighttime high crash locations. The procedure involved a literature search, a survey of states, crash data analysis, …

Signal Mast Arm Fatigue Failure Investigation, Genda Chen, Michael G. Barker, Lokeswarappa R. Dharani, Christopher W. Ramsay

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Missouri Department of Transportation (MoDOT) has discovered and documented failures in several cantilever mast arms in the recent years. The failures were primarily by fatigue at the weld of the arm to the base plate attached to the mast. With over 6000 mast arms in service in Missouri, the failures raised concerns with the existing mast arm inventory and future mast arm design. This report presents findings from an effort to determine the cause of unexpected cracking in Missouri mast arms. Three causes of premature failure were investigated: the stress ranges experienced at the weld detail were higher than …

Osteon Pullout In The Equine Third Metacarpal Bone: Effects Of Ex Vivo Fatigue, L. P. Hiller, S. M. Stover, V. A. Gibson, J. C. Gibeling, C. S. Prater, S. J. Hazelwood, O. C. Yeh, R. B. Martin

Biomedical Engineering

An important concept in bone mechanics is that osteons influence mechanical properties in several ways, including contributing to toughness and fatigue strength by debonding from the interstitial matrix so as to "bridge" developing cracks. Observations of "pulled out" osteons on fracture surfaces are thought to be indicative of such behavior. We tested the hypothesis that osteon pullout varies with mode of loading (fatigue vs. monotonic), cortical region, elastic modulus, and fatigue life. Mid-diaphseal beams from the dorsal, medial, and lateral regions of the equine third metacarpal bone were fractured in four point bending by monotonic loading to failure under deflection …

Microwave Reflection Properties Of Concrete Exposed Periodically To Chloride Solution Of 3% Salinity And Compression Force, Joseph Toby Case, Eric Gallaher, Shanup Peer, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave nondestructive evaluation (NDE) techniques applied to mortar have proven successful in the past for detecting mixture constitutes, salt ingress, loading and cure state monitoring. In this paper, a similar microwave NDE technique is used to evaluate reflection properties of concrete for cyclical exposure to salt ingress and loading at S-(2.6-3.95 GHz) and X-(8.2-12.4GHz) microwave frequency bands. Four identical cubic specimens were prepared: one soaked in distilled water, one soaked in a 3%-salt solution, one soaked in a 3%-salt solution and loaded and finally one that was neither soaked nor loaded. Using both magnitude and phase of microwave reflection coefficient, …

Dc Power-Bus Noise Isolation With Power-Plane Segmentation, Wei Cui, Jun Fan, Yong Ren, Hao Shi, James L. Drewniak, Richard E. Dubroff

Electrical and Computer Engineering Faculty Research & Creative Works

Power-plane segmentation is often used for DC power-bus noise isolation in multilayer printed circuit board (PCB) designs. To achieve a desirable noise isolation, different power-plane segmentations can be used. A suitable modeling approach, as well as measurements, were employed in this work to study the noise isolation with several power-plane segmentation designs. The geometries studied include power islands, and totally segmented power planes. The effects of the power-bus noise isolation with different types of power island connections, locations of segmentation, and shapes were analyzed, and compared. The modeled and measured results show that suitable power-plane segmentation can result in significant …

Metrics And Models For Cost And Quality Of Component-Based Software, Sahra Sedigh, Arif Ghafoor, Raymond A. Paul

Electrical and Computer Engineering Faculty Research & Creative Works

Quality and risk concerns currently limit the application of commercial off-the-shelf (COTS) software components to non-critical applications. Software metrics can quantify factors contributing to the overall quality of a component-based system, and models for tradeoffs between cost and various aspects of quality can guide quality and risk management by identifying and eliminating sources of risk. This paper discusses metrics and models that can be used to alleviate quality concerns for COTS-based systems, enabling the use of COTS components in a broader range of applications.

Space Radiation Effects In Electronic Components, Len Adams

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation delivered by Professor Len Adams in May of 2003 on "Space Radiation Effects in Electronic Components."

Dnepr Space Launch System, Robert J. Twiggs, Isc Kosmotras

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by ISC Kosmotras and Professor Bob Twiggs titled "DNEPR Space Launch System" from May of 2003.

Co-Operation In Health And Safety: A Game Theory Analysis, Sylvie Nadeau

The University of New Hampshire Law Review

[Excerpt] “Health and safety managers face complex challenges in today’s production environments. They are confronted with increasingly flexible, autonomous and polyvalent contexts. Asymmetry of information on the workplace is widespread because various intervening parties rely on information lacking conformity. Social partners generate and use information which supports or benefits their pursuit of differing goals. Ascertaining and controlling this information can prove both difficult and costly. When addressing health and safety issues, one intervening partner alters or changes behavior in response to changes introduced by the other side. Strategic behaviors result, based on post-contract opportunism (moral hazard) and alliances with partners …

Development Of An Atrophic Nonunion Model And Comparison To A Closed Healing Fracture In Rat Femur, Takeshi Kokubu, David J. Hak, Scott J. Hazelwood, A. Hari Reddi

Biomedical Engineering

Although most fractures heal, some fail to heal and become nonunions. Many animal models have been developed to study problems of fracture healing. The majority of nonunion models have involved segmental bone defects, but this may not adequately represent the biologic condition in which nonunions clinically develop. The objective of the present study is to develop a nonunion model that better simulates the clinical situation in which there is soft tissue damage including periosteal disruption and to compare this model to a standard closed fracture model utilizing identical fracture stabilization, providing a similar mechanical environment. A total of 96 three …

Lumped-Circuit Model Extraction For Vias In Multilayer Substrates, Jun Fan, James L. Drewniak, James L. Knighten

Electrical and Computer Engineering Faculty Research & Creative Works

Via interconnects in multilayer substrates, such as chip scale packaging, ball grid arrays, multichip modules, and printed circuit boards (PCB) can critically impact system performance. Lumped-circuit models for vias are usually established from their geometries to better understand the physics. This paper presents a procedure to extract these element values from a partial element equivalent circuit type method, denoted by CEMPIE. With a known physics-based circuit prototype, this approach calculates the element values from an extensive circuit net extracted by the CEMPIE method. Via inductances in a PCB power bus, including mutual inductances if multiple vias are present, are extracted …

Numerical Modeling Of Electrostatic Discharge Generators, Kai Wang, David Pommerenke, Ramachandran Chundru, Thomas Van Doren, James L. Drewniak, A. Shashindranath

Electrical and Computer Engineering Faculty Research & Creative Works

The discharge current and the transient fields of an electrostatic discharge (ESD) generator in the contact mode are numerically simulated using the finite-difference time-domain method. At first the static field is established. Then the conductivity of the relay contact is changed, which initiates the discharge process. The simulated data are used to study the effect of design choices on the current and fields. They are compared to measured field and current data using multidecade broadband field and current sensors. The model allows accurate prediction of the fields and currents of ESD generators, thus it can be used to evaluate different …

A Dual-Current Method For Characterizing Common-Mode Loop Impedance, Geping Liu, Yimin Ding, Chingchi Chen, Richard W. Kautz, James L. Drewniak, David Pommerenke, Marina Koledintseva

Electrical and Computer Engineering Faculty Research & Creative Works

The definition of common-mode loop impedance is proposed instead of the ambiguous definition of common-mode impedance. Moreover, a non-invasive measurement method to characterize the common-mode loop impedance using dual clamp-on current probe is presented herein. The frequency responses of the current probes are de-embedded through a calibration procedure. Independent direct measurements using a network analyzer corroborate the validity of the Dual-Current-Probe Method.

Calculation Of The Impedance Of A Rectangular Waveguide Aperture In The Presence Of A Loaded Dipole Antenna Embedded In A Generally Lossy Material, Dana M. Hughes, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The use of a combined embedded modulated scattering technique, utilizing a PIN diode-loaded dipole probe, and near-field microwave nondestructive testing technique, utilizing an open-ended rectangular waveguide, has been investigated as a means for determining the complex dielectric constant in which the MST probe is embedded. For this, the formulation of the forward problem of calculating the modulated reflection coefficient, measured at the aperture of the waveguide, is presented here, This formulation is based upon the reciprocity theorem for two antennae, and utilizes the near-field radiation pattern of a rectangular waveguide aperture and current distribution along the length of a dipole …

Comparison Of Water And Saltwater Movement In Mortar Based On A Semi-Empirical Electromagnetic Model, Shanup Peer, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The presence of chloride ions in steel-reinforced structures leads to the corrosion of the reinforcement thus compromising the integrity and strength of the structure. Thus, it is of great importance to be able to non-destructively detect and evaluate the free chloride content in concrete. To that end, an investigation was initiated where two mortar cubes were soaked in distilled water and saltwater solutions, respectively. Their temporal microwave reflection properties were measured using open-ended rectangular waveguides on a daily basis for three cycles, each lasting 35 days. A semi-empirical electromagnetic model was then developed to simulate the reflection properties of the …

Thermoacoustic Refrigerator, Nathan A. Hammond

Undergraduate Honors Capstone Projects

Thermoacoustic refrigerators have typically been designed to cool an isolated working fluid, necessitating a heat exchanging device to draw heat from the outside target fluid into the cooled working fluid. For example, a thermoacoustic refrigerator designed to chill air might utilize argon as an isolated working fluid, necessitating a heat exchanger to draw heat from the air to the argon. A second heat exchanger would be required to draw heat from the argon to a cold sink.

A design team at Utah State University has created a thermoacoustic refrigerator which uses air at atmospheric pressure as its working fluid. By …

Wright Flyer Project, John William Love

Undergraduate Honors Capstone Projects

The time is December of 1903. The place is Kitty Hawk, North Carolina; an inhospitable, barren, and windy wasteland. Yet, in this forsaken desert, something magical and historic was about to take place. Many people believed that the Wright Brothers were insane to even fantasize about flight. Man kind was not suppose to fly. The brothers were likened to the myth of Icarus, and warned that those who try to fly to close to the sun will meet an untimely demise. Luckily, the jeers were not enough to sway the Wright Brothers from believing. The home-built aircraft started down the …

Development Of New Heat Sink Technology For High-Density Microprocessors, Pedro Lopez Jr.

Theses and Dissertations - UTB/UTPA

This study investigates the performance of existing heat sinks and compares it with two heat-exchanger prototypes: aluminum-foam heat sink and PCM (phase-change material)-filled heat sink. Kapton flexible heaters are used to replicate the heat produced by a computer's CPU (central processing unit). A number of thermocouples are connected between the heater and the heat sink being used to measure the component's temperature. The thermocouples are also connected to a data acquisition card to collect the data using a LabVIEW program. The values obtained are compared to data published in literature to validate the experiments and the setup. This setup is …

Bs News

Building Services Engineering

No abstract provided.

Optimal Beam Splitters For The Division-Of-Amplitude Photopolarimeter, R. M.A. Azzam, A. De

Electrical Engineering Faculty Publications

Optimal optical parameters of the beam splitter that is used in the division-of-amplitude photopolarimeter are determined. These are (1) 50%–50% split ratio of the all-dielectric beam splitter, (2) differential phase shifts in reflection and transmission Δ_r and Δ_t that differ by ±π/2, and (3) ellipsometric parameters (ψ_r, ψ_t)= (27.368°, 62.632°) or (62.632°, 27.368°). It is also shown that for any nonabsorbing beam splitter that splits incident unpolarized light equally, the relationship ψ_r+ψ_t=π/2 is always satisfied.

Rapid Prototyping Of Digital Controls For Power Electronics, Antonello Monti, Enrico Santi, Roger A. Dougal, Marco Riva

Faculty Publications

The process for designing digital controls for power electronics is typically quite convoluted and affords many opportunities for errors to occur. We present here a new and complete, method for rapid prototyping of digital controls that allows rapid realization of new designs. The approach uses a collection of tools that include both software (the virtual test bed (VTB) and Matlab/Simulink) and hardware (dSpace DSP). An example application of the methodology completes the discussion.

Inside Unlv, Gian Galassi, Richard Morgan, Carol C. Harter

Inside UNLV

No abstract provided.

Coding, Decoding, And Recovery Of Clock Synchronization In Digital Multiplexing System, Hansheng Wang, Xiaoyi Qin, Lieguang Zeng, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

High-speed broadband digital communication networks rely on digital multiplexing technology where clock synchronization, including processing, transmission, and recovery of the clock, is the critical technique. This paper interprets the process of clock synchronization in multiplexing systems as quantizing and coding the information of clock synchronization, interprets clock justification as timing sigma-delta modulation (TΔ-ΣM), and interprets the jitter of justification as quantization error. As a result, decreasing the quantization error is equivalent to decreasing the jitter of justification. Using this theory, the paper studies the existing jitter-reducing techniques in transmitters and receivers, presents some techniques that can decrease the quantization error …

Isomorphic Strategy For Processor Allocation In K-Ary N-Cube Systems, Moonsoo Kang, Chansu Yu, Hee Yong Youn, Ben Lee, Myungchul Kim

Electrical and Computer Engineering Faculty Publications

Due to its topological generality and flexibility, the k-ary n-cube architecture has been actively researched for various applications. However, the processor allocation problem has not been adequately addressed for the k-ary n-cube architecture, even though it has been studied extensively for hypercubes and meshes. The earlier k-ary n-cube allocation schemes based on conventional slice partitioning suffer from internal fragmentation of processors. In contrast, algorithms based on job-based partitioning alleviate the fragmentation problem but require higher time complexity. This paper proposes a new allocation scheme based on isomorphic partitioning, where the processor space is partitioned into higher dimensional isomorphic subcubes. The …

Guest Editorial: Text And Web Mining, Ah-Hwee Tan, Philip S. Yu

Research Collection School Of Computing and Information Systems

Text mining and web mining are two interrelated fields that have received a lot of attention in recent years. Text mining [1, 2] is concerned with the analysis of very large document collections and the extraction of hidden knowledge from text-based data. Web mining [3] refers to the analysis and mining of all web-related data, including web content, hyperlink structure, and web access statistics.

Final Design Report Of Computer Controller Of Robotic Arm, Kurt Niederhauser

Undergraduate Honors Capstone Projects

My Part of the project was to design the hardware. I assembled the TT8 microprocessor and designed the optocial isolation board for the input and output signals to the TT8 microprocessor. We had two boards. One board had the TT8 Processor and other chips used for regulating the affairs of the TT8 (This board I assembled), and then there was another board that had all the control signals for the TT8 (this board I had to design), which sent the signals letting the TT8 know when the robot arm had been extended or retracted as far is it could go. …

Analysis Of Lifting Performance Capacity Through An Integrated Learning Curve Model, Jose Roel Flores

Theses and Dissertations - UTB/UTPA

Physical fitness specific to job demands is necessary for jobs that require moderate or heavy effort. Fitness training is needed not just when a new job is learned but also when an individual has been away from the job for a few weeks and returns to perform the task. The basic problem is to have a good understanding of the dynamics of performance capacities to establish training and retraining regimes to prevent overexertion. To obtain this, a better understanding of the behavior of performance capacity over time is necessary. A performance capacity training regimen was designed for tasks that required …

Analysis Of Performance Capacity Of Hand Grip Through An Integrated Learning Curve Model, Miguel Torres

Theses and Dissertations - UTB/UTPA

There are few activities or work task in the manufacturing industry that does not involve grip strength. That is why it is in the best interest of the manufacturing industry to have an understanding of the optimum grip strength gain capacity over time that would lead to better performance, accuracy and most of all prevent hand grip related injuries. For that reason, this thesis was concentrated in discovering a possible basic working model for estimating grip strength over time for a specific grip strength activity. The first step was to observe the trend characteristics of the strength gain data over …

Expert System Development For Hard Disk Drive Failure Analysis, Fernando Rodriguez Rosas

Theses and Dissertations - UTB/UTPA

The Computer's Hard Disk Drive is a complex high technology device, diagnosis of a failure is difficult even using sophisticated test equipments. These Drives are expensive and returning a new one when it fails within the warranty period is not an option. The failed drive must be tested and repaired. In the repair process the analysis and diagnosis of the failures is a key point in the process where decisions regarding the repair process that the failed Drive will follow. Therefore, there is a requirement to perform an effective analysis and provide an accurate diagnosis. The standard system utilized for …