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Full-Text Articles in Engineering

A Spatiotemporal Query Service For Mobile Users In Sensor Networks, Chenyang Lu, Guoliang Xing, Octav Chipara, Chien-Liang Fok, Sangeeta Bhattacharya May 2004

A Spatiotemporal Query Service For Mobile Users In Sensor Networks, Chenyang Lu, Guoliang Xing, Octav Chipara, Chien-Liang Fok, Sangeeta Bhattacharya

All Computer Science and Engineering Research

This paper presents MobiQuery, a spatiotemporal query service that allows mobile users to periodically gather information from their surrounding areas through a wireless sensor network. A key advantage of MobiQuery lies in its capability to meet stringent spatiotemporal performance constraints crucial to many applications. These constraints include query latency, data freshness and fidelity, and changing query areas due to user mobility. A novel just-in-time prefetching algorithm enables MobiQuery to main-tain robust spatiotemporal guarantees even when nodes op-erate under extremely low duty cycles. Furthermore, it sig-nificantly reduces the storage cost and network contention caused by continuous queries from mobile users. We …


Particles In The Great Pinatubo Volcanic Cloud Of June 1991:The Role Of Ice, Song Guo, William I. Rose, Gregg J. S. Bluth, M. I. Watson May 2004

Particles In The Great Pinatubo Volcanic Cloud Of June 1991:The Role Of Ice, Song Guo, William I. Rose, Gregg J. S. Bluth, M. I. Watson

Department of Geological and Mining Engineering and Sciences Publications

Pinatubo's 15 June 1991 eruption was Earth's largest of the last 25 years, and it formed a substantial volcanic cloud. We present results of analysis of satellite-based infrared remote sensing using Advanced Very High Resolution Radiometer (AVHRR) and TIROS Operational Vertical Sounder/High Resolution Infrared Radiation Sounder/2 (TOVS/HIRS/2) sensors, during the first few days of atmospheric residence of the Pinatubo volcanic cloud, as it drifted from the Philippines toward Africa. An SO2-rich upper (25 km) portion drifted westward slightly faster than an ash-rich lower (22 km) part, though uncertainty exists due to difficulty in precisely locating the ash cloud. …


Development Of Nanostructure Based Corrosion-Barrier Coatings On Steel For Transmutation Applications, Biswajit Das May 2004

Development Of Nanostructure Based Corrosion-Barrier Coatings On Steel For Transmutation Applications, Biswajit Das

Transmutation Sciences Materials (TRP)

The objective of this project is to develop a novel nanostructure based coating technology that will provide significantly improved corrosion resistance for steel in LBE at elevated temperatures (500 - 600oC), as well as provide long-term reliability under thermal cycling. The nanostructure based coatings will consist of a layer of nanoporous alumina with the pores filled with an oxidizing metal such as Cr, followed by a capping layer of alumina. Alumina, which is a robust anti-corrosion material, provides corrosion resistance at elevated temperatures. The Cr serves two purposes: (1) it acts as a solid filler material for the …


Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System, Kenneth Czerwinski, Byron Bennett May 2004

Fundamental Chemistry Of U And Pu In The Tbp-Dodecane-Nitric Acid System, Kenneth Czerwinski, Byron Bennett

Separations Campaign (TRP)

The speciation of hexavalent U and tetravalent Pu will be examined in the TBP-dodecane-nitric acid systems. This topic is chosen based on data needs for separation modeling identified by the AFCI. Emphasis will be placed on studying the influence of nitrate and acetohydroxamic acid on U and Pu speciation as well as conditions where a third phase forms in the organic phase. The organic phase will be 30% TBP in dodecane. Equal volumes of aqueous and organic phase will be used. The speciation of the actinides in the aqueous and organic phase will be determined by a number of different …


Design Concepts And Process Analysis For Transmuter Fuel Manufacturing, Georg F. Mauer May 2004

Design Concepts And Process Analysis For Transmuter Fuel Manufacturing, Georg F. Mauer

Fuels Campaign (TRP)

This proposal addresses the subject heading ‘Transmutation Fuel Development’ in the 2004 research topic list of the UNLV Transmutation Research Program (TRP) and DOE Advanced Fuel Cycle Initiative (AFCI). The large-scale deployment of remote fabrication and refabrication processes (with a capacity of approx. 100 metric tons of Minor Actinides (MA) annually) will be required for all transmutation scenarios. The objective of this project is the design, analysis, and evaluation of manufacturing processes for transmuter fuel fabrication. Fabrication processes for different fuel types differ in terms of equipment types, throughput, and cost. The evaluation of the fabrication processes will create a …


Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber May 2004

Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber

Faculty Publications

n- and p-type Ge nanowires were synthesized by a multistep process in which axial elongation, via vapor–liquid–solid (VLS) growth, and doping were accomplished in separate chemical vapor deposition steps. Intrinsic, single-crystal, Ge nanowires prepared by Au nanocluster-mediated VLS growth were surface-doped in situ using diborane or phosphine, and then radial growth of an epitaxial Ge shell was used to cap the dopant layer. Field-effect transistors prepared from these Ge nanowires exhibited on currents and transconductances up to 850 µA/µm and 4.9 µA/V, respectively, with device yields of >85%.


Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems, Ajit K. Roy May 2004

Effect Of Silicon Content On The Corrosion Resistance And Radiation-Induced Embrittlement Of Materials For Advanced Heavy Liquid Metal Nuclear Systems, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV), Los Alamos National Laboratory (LANL) and Idaho State University (ISU) is to evaluate the effect of silicon (Si) content on the corrosion behavior and radiation-induced embrittlement of martensitic stainless steels having chemical compositions similar to that of the modified 9Cr-1Mo 2 steel. Recent studies at LANL involving Alloy EP-823 of different Si content have demonstrated that increased Si content in this alloy may enhance the corrosion resistance in molten lead-bismuth-eutectic (LBE). Since very little data exists in the open literature on the beneficial effect of …


Composing Systemic Aspects Into Component-Oriented Doc Middleware, Nanbor Wang May 2004

Composing Systemic Aspects Into Component-Oriented Doc Middleware, Nanbor Wang

All Computer Science and Engineering Research

The advent and maturation of component-based middleware frameworks have sim-plified the development of large-scale distributed applications by separating system devel-opment and configuration concerns into different aspects that can be specified and com-posed at various stages of the application development lifecycle. Conventional component middleware technologies, such as J2EE [73] and .NET [34], were designed to meet the quality of service (QoS) requirements of enterprise applications, which focus largely on scalability and reliability. Therefore, conventional component middleware specifications and implementations are not well suited for distributed real-time and embedded (DRE) ap-plications with more stringent QoS requirements, such as low latency/jitter, timeliness, and …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 7, May 2004, College Of Engineering And Computer Science, Wright State University May 2004

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 7, May 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

An eight page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Nebraska Summary S466: Massey Ferguson 6480 Diesel 32-Speed, Nebraska Tractor Test Lab May 2004

Nebraska Summary S466: Massey Ferguson 6480 Diesel 32-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.


Fusion And Perspective Correction Of Multiple Networked Video Sensors, Christopher E. Neely, John W. Lookwood May 2004

Fusion And Perspective Correction Of Multiple Networked Video Sensors, Christopher E. Neely, John W. Lookwood

All Computer Science and Engineering Research

A network of adaptive processing elements has been developed that transforms and fuses video captured from multiple sensors. Unlike systems that rely on end-systems to process data, this system distributes the computation throughout the network in order to reduce overall network bandwidth. The network architecture is scalable because it uses a hierarchy of processing engines to perform signal processing. Nodes within the network can be dynamically reprogrammed in order to compose video from multiple sources, digitally transform camera perspectives, and adapt the video format to meet the needs of specific applications. A prototype has been developed using reconfigurable hardware that …


Run-Time Modification Of The Class Hierachy In A Live Java Development Environment, Joel R. Brandt May 2004

Run-Time Modification Of The Class Hierachy In A Live Java Development Environment, Joel R. Brandt

All Computer Science and Engineering Research

Class hierarchy design is central to object-oriented software development. How-ever, it is sometimes difficult for developers to anticipate all the implications of a design until implementation is underway. To support experimentation with different designs, we extend prior work on live development environments to allow run-time modification of the class hierarchy. The result is a more fluid object-oriented development process, in which immediate feedback from the executing program can be used to guide hierarchy design. This thesis presents a framework and developer support for run-time modification of class inheritance relations in JPie, a live visual programming environment for Java. Most notably, …


Design And Simulation Of An Induction Skull Melting System, Taide Tan May 2004

Design And Simulation Of An Induction Skull Melting System, Taide Tan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Incorporating volatile actinides, mainly americium into a metallic fuel pin (MFP) has been a serious problem due to americium’s high vapor pressure. An Induction Skull Melting (ISM) system was identified by Argonne National Laboratory (ANL) as a potential furnace design to cast MFPs. Through the development of the ISM system, the nuclear waste feedstock can be melted and injected into the mold for fabricating MFPs in the advanced nuclear fuel cycles. The main phenomena in this system include: induction melting process, casting process and mass transfer process of americium. Issues related to ISM system design for casting MFPs are discussed …


Multi-Period Multi-Dimensional Knapsack Problem And Its Application To Available-To-Promise, Hoong Chuin Lau, M. K. Lim May 2004

Multi-Period Multi-Dimensional Knapsack Problem And Its Application To Available-To-Promise, Hoong Chuin Lau, M. K. Lim

Research Collection School Of Computing and Information Systems

This paper is motivated by a recent trend in logistics scheduling, called Available-to-Promise. We model this problem as the multi-period multi-dimensional knapsack problem. We provide some properties for a special case of a single-dimensional problem. Based on insights obtained from these properties, we propose a two-phase heuristics for solving the multi-dimensional problem. We also propose a novel time-based ant colony optimization algorithm. The quality of the solutions generated is verified through experiments, where we demonstrate that the computational time is superior compared with integer programming to achieve solutions that are within a small percentage of the upper bounds.


Inside Unlv, Gian Galassi, Andy Grossman, Donna Mcaleer, Jennifer Vaughan, Carol C. Harter, Ronald Yasbin May 2004

Inside Unlv, Gian Galassi, Andy Grossman, Donna Mcaleer, Jennifer Vaughan, Carol C. Harter, Ronald Yasbin

Inside UNLV

No abstract provided.


Modified Art 2a Growing Network Capable Of Generating A Fixed Number Of Nodes, Ji He, Ah-Hwee Tan, Chew-Lim Tan May 2004

Modified Art 2a Growing Network Capable Of Generating A Fixed Number Of Nodes, Ji He, Ah-Hwee Tan, Chew-Lim Tan

Research Collection School Of Computing and Information Systems

This paper introduces the Adaptive Resonance Theory under Constraint (ART-C 2A) learning paradigm based on ART 2A, which is capable of generating a user-defined number of recognition nodes through online estimation of an appropriate vigilance threshold. Empirical experiments compare the cluster validity and the learning efficiency of ART-C 2A with those of ART 2A, as well as three closely related clustering methods, namely online K-Means, batch K-Means, and SOM, in a quantitative manner. Besides retaining the online cluster creation capability of ART 2A, ART-C 2A gives the alternative clustering solution, which allows a direct control on the number of output …


Automatic Determination Of Factors For Real-Time Garbage Collection, Tobias Mann, Ron K. Cytron Apr 2004

Automatic Determination Of Factors For Real-Time Garbage Collection, Tobias Mann, Ron K. Cytron

All Computer Science and Engineering Research

Several approaches to hard, real-time garbage collection have been recently proposed. All of these approaches require knowing certain statistical properties about a program's execution, such as the maximum extent of live storage, the rate of storage allocation, and the number of non-null object references. While these new approaches offer the possibility of guaranteed, reasonably bounded behavior for garbage collection, the determination of the required information may not be straight forward for the application programmer. In this paper we present evidence suggesting that the necessary factors can vary widely over the program's execution, indicating that an automatic, phased approach may be …


Theoretical Modeling Of Protective Oxide Layer Growth In Non-Isothermal Lead-Alloys Coolant Systems, Yitung Chen, Jinsuo Zhang, Jichun Li Apr 2004

Theoretical Modeling Of Protective Oxide Layer Growth In Non-Isothermal Lead-Alloys Coolant Systems, Yitung Chen, Jinsuo Zhang, Jichun Li

Transmutation Sciences Materials (TRP)

The goal of the proposed research project is to provide basic understanding of the protective oxide layer behaviors and to develop oxide layer growth models of steels in non-isothermal leadalloys (lead or lead-bismuth eutectic) coolant systems. It is widely recognized that the corrosiveness of the lead-alloys is a critical obstacle and challenge for which it can be safely used or applied in the nuclear coolant systems. Active oxygen control technique can promote the formation of the “self-healing” oxide films on the structural material surface, drastically reducing steel corrosion and coolant contamination. Many experiments of steels exposed to flowing leadalloys have …


Development Of Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Yitung Chen, Sean Hsieh Apr 2004

Development Of Integrated Process Simulation System Model For Spent Fuel Treatment Facility (Sftf) Design, Yitung Chen, Sean Hsieh

Separations Campaign (TRP)

The Advanced Fuel Cycle Initiative (AFCI) and Transmutation Research Program-University Participation Program (TRP-UPP) supported by Department of Energy of the United States have been developing many important technologies for the transmutation of nuclear waste to address long-term disposal issues. While successfully embedding AMUSE module into a dedicated System Engineering Model (TRPSEMPro), developed by the Nevada Center for Advanced Computational Methods (NCACM) at the University of Nevada-Las Vegas collaborating with Argonne National Laboratory (ANL), ANL is interested in further simulating the Light Water Reactor (LWR) Spent Fuel Treatment Facility (SFTF) combining commercial process simulation and analysis packages and core calculation of …


Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy Apr 2004

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV) and Idaho State University (ISU) is to evaluate the feasibility of determining residual stresses of welded, bent (three-point-bend), and cold-worked engineering materials using a new nondestructive technique based on positron annihilation spectroscopy (PAS). The proposed technique is to use γ-rays from a small MeV electron linear accelerator (Linac) to generate positrons inside the test sample via 2 pair production. This method can be used for materials characterization and investigation of defects in thick samples that usually cannot be accomplished by conventional positron technique or other …


Detection Of Closed Hyperstreamlines, Thomas Wischgoll Apr 2004

Detection Of Closed Hyperstreamlines, Thomas Wischgoll

Computer Science and Engineering Faculty Publications

No abstract provided.


2004 - The Ninth Annual Symposium Of Student Scholars Apr 2004

2004 - The Ninth Annual Symposium Of Student Scholars

Symposium of Student Scholars Program Books

The full program book from the Ninth Annual Symposium of Student Scholars, held on April 16, 2004. Includes abstracts from the presentations and posters.


Re-Evaluation Of So2 Release Of The 15 June 1991 Pinatubo Eruption Using Ultraviolet And Infrared Satellite Sensors, Song Guo, Gregg J. S. Bluth, William I. Rose, M. I. Watson, A. J. Prata Apr 2004

Re-Evaluation Of So2 Release Of The 15 June 1991 Pinatubo Eruption Using Ultraviolet And Infrared Satellite Sensors, Song Guo, Gregg J. S. Bluth, William I. Rose, M. I. Watson, A. J. Prata

Department of Geological and Mining Engineering and Sciences Publications

In this study, ultraviolet TOMS (Total Ozone Mapping Spectrometer) satellite data for SO2 are re-evaluated for the first 15 days following the 15 June 1991 Pinatubo eruption to reflect new data retrieval and reduction methods. Infrared satellite SO2 data from the TOVS/HIRS/2 (TIROS (Television Infrared Observation Satellite) Optical Vertical Sounder/High Resolution Infrared Radiation Sounder/2) sensor, whose data sets have a higher temporal resolution, are also analyzed for the first time for Pinatubo. Extrapolation of SO2 masses calculated from TOMS and TOVS satellite measurements 19–118 hours after the eruption suggest initial SO2 releases of 15 ± 3 …


Reconstruction Of Two-Dimensional Magnetopause Structures From Cluster Observations: Verification Of Method, H. Hasegawa, B. U. Ö Sonnerup, M. W. Dunlop, A. Balogh, S. E. Haaland, B. Klecker, G. Paschmann, B. Lavraud, I. Dandouras, H. Reme Apr 2004

Reconstruction Of Two-Dimensional Magnetopause Structures From Cluster Observations: Verification Of Method, H. Hasegawa, B. U. Ö Sonnerup, M. W. Dunlop, A. Balogh, S. E. Haaland, B. Klecker, G. Paschmann, B. Lavraud, I. Dandouras, H. Reme

Dartmouth Scholarship

A recently developed technique for reconstructing approximately two-dimensional (∂/∂z≈0), time-stationary magnetic field structures in space is applied to two magnetopause traversals on the dawnside flank by the four Cluster spacecraft, when the spacecraft separation was about 2000km. The method consists of solving the Grad-Shafranov equation for magnetohydrostatic structures, using plasma and magnetic field data measured along a single spacecraft trajectory as spatial initial values. We assess the usefulness of this single-spacecraft-based technique by comparing the magnetic field maps produced from one spacecraft with the field vectors that other spacecraft actually observed. For an optimally selected invariant (z)-axis, the correlation between …


Santa Clara Magazine, Volume 45 Number 4, Spring 2004, Santa Clara University Apr 2004

Santa Clara Magazine, Volume 45 Number 4, Spring 2004, Santa Clara University

Santa Clara Magazine

8 - TOP TEACHERS By Elizabeth Kelley Gillogly '93-Meet three SCU professors who received University awards for teaching excellence and curriculum innovations.

10 - BLAZING THE TRAIL By Victoria Hendel De La O. There are many unique challenges and rewards for the hundreds of first-generation college students at SCU.

14 - THE SCU DIFFERENCE By Margaret Avritt. The value of an SCU education goes beyond statistics and scores. Students at this university have experiences that engage and transform them.

18 - MIND OVER MONEY By Hersh Shefrin and Meir Statman. Two SCU professors of finance explore how psychology can help …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 6, April 2004, College Of Engineering And Computer Science, Wright State University Apr 2004

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 20, Number 6, April 2004, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A six page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Anisotropy Of Exchange Stiffness And Its Effect On The Properties Of Magnets, K. D. Belashchenko Apr 2004

Anisotropy Of Exchange Stiffness And Its Effect On The Properties Of Magnets, K. D. Belashchenko

Kirill Belashchenko Publications

Using the spin-spiral formulation of the tight-binding linear muffin-tin orbital method, the principal components of the exchange stiffness tensor are calculated for typical hard magnets including tetragonal CoPt-type and hexagonal YCo5 alloys. The exchange stiffness is strongly anisotropic in all studied alloys. This anisotropy makes the domain wall surface tension anisotropic. Competition between this anisotropic surface tension and magnetostatic energy controls the formation and dynamics of nanoscale domain structures in hard magnets. Anisotropic domain wall bending is described in detail from the general point of view and with application to cellular Sm–Co magnets. It is shown that the repulsive …


Willamette River Basin Temperature Tmdl Model: Model Scenarios, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells Apr 2004

Willamette River Basin Temperature Tmdl Model: Model Scenarios, Robert Leslie Annear, Michael Lee Mckillip, Sher Jamal Khan, Chris Berger, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The State of Oregon Department of Environmental Quality (DEQ) is developing a TMDL for temperature in the Willamette River basin shown in Figure 1. The study area included the Willamette River and all major tributaries (except the Tualatin River where a TMDL process was already concluded). A large section of the Columbia River was also modeled to provide adequate boundary representation of tidal flows in the lower Willamette River. The Willamette River below the Oregon City Falls in the Portland metropolitan area has a typical diurnal tidal range of 1 m. The development of a dynamic model of temperature and …


Generic Performance Evaluation Tool Implementation For An Imaging Fourier Transform Spectrometer, James M. Mengert Apr 2004

Generic Performance Evaluation Tool Implementation For An Imaging Fourier Transform Spectrometer, James M. Mengert

Electrical & Computer Engineering Theses & Dissertations

Evaluation software for analyzing general analytical model applications utilizing MATLAB is presented in this thesis. The focus is to provide an interactive environment for the evaluation of model applications relating to an Imaging Fourier Transform Spectrometer. The Generic Performance Evaluation Tool (GPET) was developed by researchers at Old Dominion University and NASA-Langley Research Center and was a NASA-Langley Research Center sponsored project. GPET is capable of producing a multitude of object-oriented input data for any number of individual model applications. The tool is also capable of creating user-defined input interfaces for the purpose of viewing and/or editing input object data, …


Speaker Normalization For Improved Automatic Speech Recognition For Digital Libraries, Wei Wang Apr 2004

Speaker Normalization For Improved Automatic Speech Recognition For Digital Libraries, Wei Wang

Electrical & Computer Engineering Theses & Dissertations

The context of this thesis work is the improvement of automatic speech recognition (ASR) for use with digital libraries. First, commonly used multimedia file formats and codecs are surveyed with the objective of identifying those formats that preserve speech quality while keeping file sizes compact. The main contribution of the work is a new technique for speaker adaptation based on frequency scale modifications. The frequency scale is modified using a minimum mean square error matching of a spectral template for each speaker to a "typical speaker" spectral template. Each spectral template is computed from the average amplitude-normalized spectra of several …