Engineering Commons^™

Modeling And Analysis Of Soft-Test/Repair For Ccd-Based Digital X-Ray Systems, Byoungjae Jin, Nohpill Park, Koshy M. George, Minsu Choi, Mark B. Yeary

Electrical and Computer Engineering Faculty Research & Creative Works

Modern X-ray imaging systems evolve toward digitization for reduced cost, faster time-to-diagnosis, and improved diagnostic confidence. For the digital X-ray systems, charge coupled device (CCD) technology is commonly used to detect and digitize optical X-ray image. This paper presents a novel soft-test/repair approach to overcome the defective pixel problem in CCD-based digital X-ray systems through theoretical modeling and analysis of the test/repair process. There are two possible solutions to cope with the defective pixel problem in CCDs: one is the hard-repair approach and another is the proposed soft-test/repair approach. Hard-repair approach employs a high-yield, expensive reparable CCD to minimize the …

Viewing The Learning Process: Assessment Via Usability Testing, Vicki M. Eller, Steve Eugene Watkins, Richard H. Hall

Business and Information Technology Faculty Research & Creative Works

Learning through Computer-Based Activities Provides a Multi-Modal Approach in Which the User Can Select the Educational Media and Process. Effective Development of These Activities Requires an Understanding of User Interactivity. Traditional Assessment, Such as Test Scores and Subjective Surveys, Looks at End Results and Attitudes. This Method Does Not Monitor the Learning Process. in Particular Developer Needs to Accommodate Diverse Usage Preferences and Choices. Hence, Assessment Should Involve Usability Measures that Are Quantitative and Qualitative. Usability Testing Records Usage Patterns and User Reactions. a Usability Laboratory Was Created at the University of Missouri-Rolla. It is Supplements the Traditional Assessment for …

Influence Of Isoflurane On Left Atrial Function In Dogs With Pacing-Induced Cardiomyopathy: Evaluation With Pressure-Volume Relationships, Franz Kehl, John F. Ladisa, Douglas Anthony Hettrick, Judy R. Kersten, David C. Warltier, Paul S. Pagel

Biomedical Engineering Faculty Research and Publications

Objective

The actions of volatile anesthetics on left ventricular (LV) function in normal and failing hearts have been previously evaluated, but the effects of these agents on left atrial (LA) function in the presence of LV dysfunction are unknown. The hypothesis was tested that isoflurane alters LA mechanics evaluated with pressure-volume relations.

Design

Prospective.

Setting

Laboratory.

Participants

Barbiturate-anesthetized dogs (n = 8) were instrumented for measurement of aortic, LA, and LV pressures (micromanometers), and LA volume (epicardial orthogonal sonomicrometers) after 3 weeks of rapid ventricular pacing (220 beats/min).

Interventions

LA myocardial contractility (E_es) was assessed with end-systolic pressure-volume …

Chemical Kinetics And Thermal Hydraulics Of Lead Bismuth Flow Loops, Kanthi Kiran Dasika

UNLV Theses, Dissertations, Professional Papers, and Capstones

The objective of the thesis is to study the effect of chemical kinetics and thermal hydraulics of Lead Bismuth Eutectic (LBE) flow in the Materials Test Loop (MTL). The Materials Test Loop, also known as the Delta Loop, was built in Los Alamos National Laboratories (LANL) to obtain the experimental data for corrosion estimation and analysis. It is a well-known fact that corrosion plays an important role in the design of nuclear thermal hydraulic systems. Since the MTL is a multi-section closed system that differs in diameter from one part to another, an intensive study on the overall and regional …

Development Of A Systems Engineering Model For Chemical Separation Process, Lijian Sun

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis is concerned with the efforts to develop a general-purpose systems engineering model software TRPSEMPro1 that can be used to improve productivity in the design process. Different features of TRPSEMPro will be presented in this thesis. First, Systems Engineering technology is presented, followed by the exposition of different numerical optimization technologies and DOE (Design of Experiments) study technologies. Second, the detailed software process, Object-Oriented Analysis and Design (OOA&D) for the TRPSEMPro is presented. All the design data models are expressed by using Unified Modeling Language (UML).

AMUSESimulator is another software package which has been designed and implemented in order …

Color Management Of Desktop Input Devices: Quantitative Analysis Of Profile Quality, Xiaoying Rong

Masters Theses

This thesis investigates the color management principle and input device profiling. The input devices discussed in this thesis are flatbed scanners.

In this thesis, the human visual system, CIE L*a*b* color space, ICC profiles are reviewed, and the evaluation of profile quality is discussed. Grayscale and standard color targets of three primary suppliers are used to create profiles for a scanner. The quantitative analyses of the quality of different profiles, created by two primary commercial profiling software, are conducted according to the Delta-E of the CIE L*a*b* color space. Finally, the relationship of different color targets and profiles for desktop …

Bs News

Building Services Engineering

No abstract provided.

Ultracompact High-Efficiency Polarizing Beam Splitter With A Hybrid Photonic Crystal And Conventional Waveguide Structure, J. Cai, S. Kim, Gregory P. Nordin, J. Jiang

Faculty Publications

We propose an ultracompact high-efficiency polarizing beam splitter that operates over a wide wavelength range and is based on a hybrid photonic crystal and a conventional waveguide structure. Within a small area (15 mm 3 10 mm), this polarizing beam splitter separates TM- and TE-polarized modes into orthogonal output waveguides. Results of simulations with the two-dimensional finite-difference time-domain method show that 99.3% of TM-polarized light is def lected by the photonic crystal structure (with a 28.0-dB extinction ratio), whereas 99.0% of TE-polarized light propagates through the structure (with a 32.2-dB extinction ratio). Wave vector diagrams are employed to explain the …

Design Of Asphalt Concrete Mixtures For Pavement Maintenance And Rehabilitation, Mubarak Bakheet Gaith Al-Falahi

Theses

The main objective of the thesis is to develop a knowledge base for the design of asphalt concrete mixtures suiting various types and causes of pavement distress and to develop supporting guidelines for the selection of aggregate types, gradation and binder contents for desirable mixture properties.

To achieve this objective, a two-level model was developed. The upper-level is a Factorial Experimental Design Model (FEDM) for the pavement condition evaluation. It can be used as a prediction tool to estimate the Pavement Condition Index (PCI), and determine the percentages of the types of distresses (Load, Environmental, Others). The upper-level model was …

A Fit-Gap Analysis Of E-Business Curricula Vs. Industry Need, S. Davis, Keng Siau, K. Dhenuvakonda

Research Collection School Of Computing and Information Systems

The alignment of e-business academic programs with the e-business market is examined using a fit-gap analysis. Two high-end business schools, ranked independently by US News and Business Week, were chosen as sample. A total of 391 different e-commerce courses were identified, which were classified into 24 categories. Out of these, there are two broad and distinct tracks in e-business curricula, with one track paving the way for an e-business career with a prevailing focus on the business aspect and the other track leading to a career focusing on technology and Web-based systems development. Industry demand for e-business professionals and the …

Getting The "Big Picture" In Engineering: Using Narratives And Conceptual Maps, Glenn W. Ellis, Borjana Mikic, Alan N. Rudnitsky

Engineering: Faculty Publications

The features and progress of Picker Engineering Program at Smith College are discussed. This program is the first undergraduate program leading to a degree in engineering at a women's liberal arts college. The program's goal is to educate engineers who are adaptable to the rapidly changing demands of society. The strategies which focus on productive ways of processing information, ways that involve the sort of intentions and conciousness necessary for meaningful learning are also discussed.

Design And Development Of A Lubrication Pump For A Horizontally Mounted Air-Conditioning Compressor., Kenneth T. Gilbert

Electronic Theses and Dissertations

Horizontally mounted compressors offer the advantage of reduced height in central air-conditioning units but prove difficult to produce economically due to costs associated with the manufacture of acceptable lubrication systems for the compressors. This study develops an effective, affordable oil pump for use on a horizontal compressor. Concepts are proven through testing of prototype assemblies. Test results drive modifications for future prototypes, and prototypes demonstrating adequate performance are modified for ease of manufacture.

Research in this study proves that the most suitable design results from a modification of a rotating vane pump. The pump’s modifications enable it to pump oil …

Parallel Microgenetic Algorithm Design For Photonic Crystal And Waveguide Structures, J. Cai, L. Li, Gregory P. Nordin, J. Jiang

Faculty Publications

We have developed a powerful parallel genetic algorithm design tool for photonic crystal and waveguide structures. The tool employs a small-population-size genetic algorithm (microgenetic algorithm) for global optimization and a two-dimensional finite-difference time-domain method to rigorously design and optimize the performance of photonic devices. We discuss the implementation and performance of this design tool. We demonstrate its application to two photonic devices, a defect taper coupler to connect conventional waveguides and photonic crystal waveguides, and a sharp 90˚ waveguide bend for low index contrast waveguides.

Afci Quarterly Input – Unlv October Through December, 2003, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division

Transmutation Research Program Reports (TRP)

Quarterly report highlighting research projects and objectives of the Transmutation Research Program at the Nuclear Science & Technology Division, Harry Reid Research Center.

The University of Nevada, Las Vegas supports the AFCI through research and development of technologies for economic and environmentally sound refinement of spent nuclear fuel. The UNLV program has four components: infrastructure, international collaboration, student-based research, and management and program support.

Inside Unlv, Gian Galassi, Katrina Hudak, Carol C. Harter, Eric Sandgren, Tom Hagge

Inside UNLV

No abstract provided.

Energy Efficient Routing Protocols For Mobile Ad Hoc Networks, Chansu Yu, Ben Lee, Hee Yong Youn

Electrical and Computer Engineering Faculty Publications

Although establishing correct and efficient routes is an important design issue in mobile ad hoc networks (MANETs), a more challenging goal is to provide energy efficient routes because mobile nodes' operation time is the most critical limiting factor. This article surveys and classifies the energy-aware routing protocols proposed for MANETs. They minimize either the active communication energy required to transmit or receive packets or the inactive energy consumed when a mobile node stays idle but listens to the wireless medium for any possible communication requests from other nodes. Transmission power control approach and load distribution approach belong to the former …

Dynamic Modeling Of Compliant Constant-Force Compression Mechanisms, Cameron Boyle, Larry L. Howell, Spencer P. Magleby, Mark S. Evans

Faculty Publications

A mathematical dynamic model is derived for compliant, constant-force compression-mechanisms, based on the pseudo-rigid-body model simplification of the device. The compliant constant-force compression mechanism (CFCM) is a slider mechanism incorporating large-deflection beams, which outputs near-constant-force across the range of its designed deflection. The equation of motion is successfully calibrated with empirical data from five separate mechanisms, comprising two basic configurations of CFCMs. The dynamic equation is derived from a generalized pseudo-rigid-body model. This allows every configuration to be represented by the same model, so a separate treatment is not required for each configuration. An unexpected dynamic trait of the constant-force …

Multiple Uav Cooperative Search Under Collision Avoidance And Limited Range Communication Constraints, Randal W. Beard, Timothy W. Mclain

Faculty Publications

This paper focuses on the problem of cooperatively searching, using a team of unmanned air vehicles (UAVs), an area of interest that contains regions of opportunity and regions of potential hazard. The objective of the UAV team is to visit as many opportunities as possible, while avoiding as many hazards as possible. To enable cooperation, the UAVs are constrained to stay within communication range of one another. Collision avoidance is also required. Algorithms for team-optimal and individually-optimal/team-suboptimal solutions are developed and their computational complexity compared. Simulation results demonstrating the feasibility of the cooperative search algorithms are presented.

Creating A Virtual Store Image, P. Katerattanakul, Keng Siau

Research Collection School Of Computing and Information Systems

A study was conducted to describe some of the factors that needed to be considered for a virtual store. It was revealed that the growth of e-commerce and online businesses has made it essential to understand the critical attributes of image for a virtual store. Store image was described as the way in which the store was defined by customers and several studies. The study compiled 77 designs and features into a list used to construct a survey. Four hundred and twenty-seven potential customers were requested to rate the significance of each item on the list. The information gathered identified …

Evaluation Of Event Data Recorders In Real World Crashes And Full-Scale Crash Tests, Lewis Thomas Clayton Jr.

Theses and Dissertations

With the advent of advanced safety systems in U.S. passenger vehicles, there has been increased interest shown by automakers in recording crash related parameters that ultimately lead to the deployment of these safety systems in what are known as Event Data Recorders (EDRs). Since the only other record of these parameters, specifically crash pulse, comes from staged crash tests in a controlled environment, the advent of the EDR has become increasingly important to crash researchers. The purpose of this study is to quantify the performance of EDRs in full-scale crash tests and real world crashes.

Comparison of EDRs with staged …

The Distribution Of Internal Interfaces In Polycrystals, Brent L. Adams, Bassem S. El-Dasher, Gregory S. Rohrer, Anthony D. Rollett, David M. Saylor, Paul Wynblatt

Faculty Publications

This work was supported by the MRSEC program of the National Science Foundation under Award Number DMR-0079996. Recent advances both in experimental instrumentation and computing power have made it possible to interrogate the distribution of internal interfaces in polycrystals and the three dimensional structure of the grain boundary network with an unprecedented level of detail. The purpose of this paper is to review techniques that can be used to study the mesoscopic crystallographic structure of grain boundary networks and to summarize current findings. Recent studies have shown that grain surfaces within dense polycrystals favor the same low energy planes that …

Design And Evaluation Of Processes For Fuel Fabrication: Quarterly Progress Report #9, Georg F. Mauer

Fuels Campaign (TRP)

The ninth quarter of the project covered the following:

• Mr. Richard Silva continued the development of a simulation model with a Waelischmiller hot cell robot. Rich will continue to develop detailed 3-D process simulation models as his M.Sc. thesis project.

• A paper on hot cell robotics was presented at the ANS Winter Annual Meeting and published in the ANS 2003 conference proceedings.

• Further advances on Concepts and Methods for Vision-Based Hot Cell Supervision and control, focusing on rule-based object recognition (Ph.D. Student Jae-Kyu Lee)

• Graduate student Jamil Renno created simulations of more complex fuel manufacturing and …

Modeling Corrosion In Oxygen Controlled Lbe Systems With Coupling Of Chemical Kinetics And Hydrodynamics-Task V: Fourth Quarterly Report 09/01/2003-11/30/2003, Samir Moujaes, Yitung Chen

Transmutation Sciences Materials (TRP)

The Lead-Bismuth eutectic (LBE) has been determined from previous experimental studies by the Russians and the European scientific community to be a potential material that can be used as a spallation target and coolant for the TRP proposed application. Properly controlling the oxygen content in LBE can drastically reduce the LBE corrosion to structural steels. However, existing knowledge of material corrosion performance was obtained from point-wise testing with only very sparse experimental data. Scientists have noticed that the concentration of oxygen dissolved in the liquid alloy could control the corrosion rate of steels exposed to Pb or Pb-Bi. At high …

Preparation And Characterization Of Y-Type Carbon Nanotubes By Using Anodized Alumina Oxide (Aao) Template, Jing Zhang, Quan-Yong Gao, Yong Yang

Journal of Electrochemistry

In this work, potential-modulation method was used in two-step anodization process to make an AAO template with Y-type nanochannels. Then Y-type carbon nanotubes with controlled length and branch angle were prepared in the template based on chemical vapor decomposion (CVD) method with Co particles as catalyst and C₂H₂ as carbon source. The Y-type nanotube branches exhibit the angle distribution ranging from 20° to 120°. The results demonstrated that the oxidation potential should be responsible for the angles and length of the branches. Short pulse and high oxidation potential will result in the short and dense nanotube branches.

Study On The Gas Generation In Different Charging Voltage During Formation Process In Polymer Lithium-Ion Battery, Li Huang, Ming-Gang Jin, Hui-Qun Cai, Ming-Sen Zheng, Quan-Feng Dong, Jin-Kua You, Zu-Geng Lin

Journal of Electrochemistry

The gases of polymer lithium-ion battery (PLI) generated under different voltages during the first charging process were examined by means of gas chromatography (GC), and the mechanism of the gas generation was discussed. The electrolyte used in batteries was 1 mol/L LiPF₆-EC～DMC～EMC=1∶1∶1(in volume). The results showed that when the charging voltage is less than 2.5 V,  the main component of generated gases are H₂ and CO₂, and when the charging voltage is 2.5 V, EC begins to decompose. Due to the decomposition of EC, the main generated gas is C₂H₄ when the …

Electrochemical And In-Situ Scanning Tunneling Microscopy Studies On The Sb Underpotential Deposition On Cu Single Crystal Electrodes, Ji-Hong Wu, Jia-Wei Yan, Jing Tang, Wen-Yun Hu, Bing-Wei Mao

Journal of Electrochemistry

We report electrochemical and in-situ STM studies on Sb UPD onto Cu(111) and Cu(100) electrode surfaces in HClO₄ and H₂SO₄ solutions. The results indicate that the electrode surface structure as well as anion can considerably influence Sb UPD. Sb UPD on Cu(100) forms open adlayer structures, which is accompanied by surface alloying due to the more open structure of the (100) surface, On Cu(111), a more compact Sb adlayer is formed instead. Anion adsorption influences the dynamics as well as the adlayer structure of Sb UPD. Owing to the strong adsorption of SO₄^2-, …

Application Of Hydrogen-Storage Alloy Electrode In Electrochemical Reduction Of Glucose, Hui Chen, You-Gen Tang, Zheng Tang

Journal of Electrochemistry

Electrolysis of glucose was performed at constant potential using hydrogen-storage alloy as catalytic reduction electrode. It was found that the superficial treatment and activation of hydrogen-storage alloy powder had obvious effects on improving the current efficiency of sorbitol. Under the optimums, current efficiency of sorbitol by electrolyzing glucose was over 94%. The yield of sorbitol was over 80%, the lifespan of electrode was tested and analyzed, the ways of regeneration were discussed.

Study On Electrochemical Behavior Of Sus316l Stainless Steel After Surface Modification, Cheng-Hao Liang, Liang Guo, Wan Chen, Jing-Xiao Liu

Journal of Electrochemistry

The surface modification for SUS316L stainless steel was carried out by electroplating Rh, ion beam assisted deposition Ta₂O₅ and sol-gel-derived TiO₂. In Tyrode's stimulated body fluid, the surface modified samples had been investigated with electrochemical techniques. The results indicated that the electrochemical stability and dissolution were improved significantly after surface modification. Moreover, as to ion beam assisted deposition Ta₂O₅ and Sol-gel-derived TiO₂ film, the metal's d orbit electron holes filled up by the oxygen electrons made against the adsorption of hydrogen. Thus the cathode process, which is controlled by the hydrogen …

Pitting Characteristics Of Cu-50/60ni Alloys In Nacl Solution, Jie Li, Yan Niu, Shi-Zhe Song

Journal of Electrochemistry

The pitting behavior of nanocrystalline Cu-50/60Ni and cast Cu-50/60Ni alloys in different concentration of NaCl solutions has been investigated using various electrochemical methods. A logarithmic dependence of the passive breakdown potential (E_b), which is established using dynamic potential scan technic, on the chloride concentration was obtained for both alloys. The study on pitting propagation of both alloys was carried out using potential step chronocurrent method. As long as pits initiate on both alloys, the pits on nanocrystalline Cu-Ni alloys develop faster than those on cast alloys.

Preparation And Properties Of The Composite Microporous Pvdf-Hfp/Sio2 Based Polymer Electrolytes, Bao-Wen Zhang, Lu Qi, Hui Hen, Xiao-Hui Zhu, Li-Yan Liu, Yun-Xiang Ci

Journal of Electrochemistry

Microporous PVDF-HFP/SiO₂ film were prepared using a solvent/nonsolvent method-phase inversion method and the volatile plasticizers DMC, DEC or PC. The conductivity of the films increased pore volume measured by a nonsolvent uptake method. The conductivity of 1.86×10^-3 S⋅m^-1 were obtained using the liquid electrolyte LiPF₆(1 M) in EC/DMC (1:1).