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Articles 1111 - 1140 of 1292
Full-Text Articles in Entire DC Network
Towards Combining Probabilistic And Interval Uncertainty In Engineering Calculations, Scott A. Starks, Vladik Kreinovich, Luc Longpre, Martine Ceberio, Gang Xiang, Roberto Araiza, J. Beck, R. Kandathi, A. Nayak, R. Torres
Towards Combining Probabilistic And Interval Uncertainty In Engineering Calculations, Scott A. Starks, Vladik Kreinovich, Luc Longpre, Martine Ceberio, Gang Xiang, Roberto Araiza, J. Beck, R. Kandathi, A. Nayak, R. Torres
Departmental Technical Reports (CS)
In many engineering applications, we have to combine probabilistic and interval errors. For example, in environmental analysis, we observe a pollution level x(t) in a lake at different moments of time t, and we would like to estimate standard statistical characteristics such as mean, variance, autocorrelation, correlation with other measurements. In environmental measurements, we often only know the values with interval uncertainty. We must therefore modify the existing statistical algorithms to process such interval data. Such modification are described in this paper.
Santa Clara Magazine, Volume 46 Number 1, Summer 2004, Santa Clara University
Santa Clara Magazine, Volume 46 Number 1, Summer 2004, Santa Clara University
Santa Clara Magazine
8 - A PUZZLING PROFESSOR By Adam Breen. Byron Walden, an assistant professor of mathematics at SCU, draws on his knowledge of numerical analysis to create crossword puzzles for The New York Times.
10 - THE LAUNCHING PAD By Larry Sokoloff J.D. '92. Top government agencies, other universities, and companies are relying on the University's Robotics Systems Lab-and its students-to build and monitor satellites.
16 - A NOVEL TEAM By Kristin Lenore '04. The University's publishing partnership with Heyday Books aims to help preserve California's cultural legacy.
Spectroscopic And Microscopic Investigation Of The Corrosion Of 316/316l Stainless Steel By Lead-Bismuth Eutectic (Lbe) At Elevated Temperatures: Importance Of Surface Preparation, Allen L. Johnson, Denise Parsons, Julia Manzerova, Dale L. Perry, Daniel Koury, Brian D. Hosterman, John Farley
Spectroscopic And Microscopic Investigation Of The Corrosion Of 316/316l Stainless Steel By Lead-Bismuth Eutectic (Lbe) At Elevated Temperatures: Importance Of Surface Preparation, Allen L. Johnson, Denise Parsons, Julia Manzerova, Dale L. Perry, Daniel Koury, Brian D. Hosterman, John Farley
Transmutation Sciences Materials (TRP)
The corrosion of steel by lead–bismuth eutectic (LBE) is an important issue in proposed nuclear transmutation schemes. Russian scientists at the IPPE exposed steel samples to oxygen-controlled LBE at temperatures up to 823 K and exposure times up to 3000 h. We have characterized these post-exposure steel samples and unexposed controls, using scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDAX) and X-ray photoelectron spectroscopy (XPS). Previous researchers have investigated the corrosion by LBE of steel of varying composition. In the present work, we compared two samples having the same composition (standard nuclear grade 316/316L) but different surface preparation: a cold-rolled …
Inside Unlv, Holly Ivy De Vore, Carol C. Harter, Stuart Mann
Inside Unlv, Holly Ivy De Vore, Carol C. Harter, Stuart Mann
Inside UNLV
No abstract provided.
A Recommendation For An Enhanced Fujita Scale (Ef-Scale)
A Recommendation For An Enhanced Fujita Scale (Ef-Scale)
United States Department of Commerce: Staff Publications
Background
National Weather Service (NWS) personnel who are responsible for rating tornadoes have expressed frustrations in applying the Fujita Scale in a consistent and accurate manner. Weak links in a structural system or a slow-moving storm sometimes lead to an overrating of a tornado event. Several technical articles suggest that wind speeds associated with some descriptions of damage are too high. For example, a 260 mph wind speed is not required to completely destroy a well constructed house and blow away the debris. The damage occurs at significantly lower wind speeds. Minor et al. (1977) and Phan and Simiu (2003) …
Afci Quarterly Input – Unlv April Through June, 2004, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division
Afci Quarterly Input – Unlv April Through June, 2004, 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, Holly Ivy De Vore, Caryn Key, Carol C. Harter, Richard Morgan
Inside Unlv, Holly Ivy De Vore, Caryn Key, Carol C. Harter, Richard Morgan
Inside UNLV
No abstract provided.
Using Fft-Based Data Processing Techniques To Characterize Asphaltic Concrete Mixtures, Scott A. Starks, Vladik Kreinovich, Roberto Araiza, Soheil Nazarian, J. Adidhela
Using Fft-Based Data Processing Techniques To Characterize Asphaltic Concrete Mixtures, Scott A. Starks, Vladik Kreinovich, Roberto Araiza, Soheil Nazarian, J. Adidhela
Departmental Technical Reports (CS)
A natural way to test the quality of a pavement is to send signals with different frequencies through the pavement and compare the results with the signals passing through an ideal pavement. For this comparison, we must determine how, for the corresponding mixture, the elasticity E depends on the frequency f in the range from 0.1 to 10^5 Hz. It is very expensive to perform measurements in high frequency area (above 20 Hz). To avoid these measurements, we can use the fact that for most of these mixtures, when we change a temperature, the new dependence changes simply by scaling. …
Modeling, Optimization, And Flow Visualization Of Chemical Etching Process In Niobium Cavities, Sathish K. Subramanian
Modeling, Optimization, And Flow Visualization Of Chemical Etching Process In Niobium Cavities, Sathish K. Subramanian
UNLV Theses, Dissertations, Professional Papers, and Capstones
Niobium cavities are important component of the linear accelerators. Researchers have concluded that buffered chemical polishing on the inner surface of the cavity improves its performance. However the mechanism of chemical polishing is not well understood. A finite element computational fluid dynamics (CFD) model was developed to simulate the fluid flow characteristics of chemical etching process inside the cavity. The CFD model is then used to optimize the baffle design. The analysis confirmed the observation of other researchers that the iris section of the cavity received more etching than the equator regions. The baffle, which directs flow towards the walls …
O-Cell Testing Of Reinforced Concrete Driven Piles, Sanjeev Kumar, Cesar Alarcon, Alyass Hosin
O-Cell Testing Of Reinforced Concrete Driven Piles, Sanjeev Kumar, Cesar Alarcon, Alyass Hosin
International Conference on Case Histories in Geotechnical Engineering
Precast and prestressed concrete piles, approximately 12 to 18 inch diameter or width are frequently used to support heavy building and bridge structures. Fly ash has long been recognized as a construction material used frequently in several Portland cement and concrete products, structural fills, embankments, and road bases/subbases. However, use of Illinois PCC bottom ash in construction of precast concrete piles so far has been very limited, if any, mainly due to the lack of technical data to convince the engineering community that bottom ash could be used in precast and prestressed concrete piles without jeopardizing their performance and the …
Rion – Antirion Bridge Foundations: A Blend Of Design And Construction Innovation, Gregory L. Biesiadecki, Ricardo Dobry, George E. Leventis, Ralph B. Peck
Rion – Antirion Bridge Foundations: A Blend Of Design And Construction Innovation, Gregory L. Biesiadecki, Ricardo Dobry, George E. Leventis, Ralph B. Peck
International Conference on Case Histories in Geotechnical Engineering
This case history discusses the design and construction of the appropriate foundation scheme for the largest cable-stayed bridge in the world. This concession project was financed through a combination of public funds, private equity and bank loans. When completed in 2004, the Rion-Antirion Bridge will connect the Peloponnese, Greece’s southernmost peninsula, with the mainland across the Gulf of Corinth. Alternative foundation concepts that were considered included traditional driven piles, deeply embedded caissons, and soil improvement. The process of how the foundation evolved from schematics to final design, what were the driving forces, how ideas were disseminated among the Design Team, …
Towards A General Methodology For Designing Sub-Noise Measurement Procedures, Roberto Osegueda, George R. Keller, Scott A. Starks, R. Araiza, Dm. Bizyaev, Vladik Kreinovich
Towards A General Methodology For Designing Sub-Noise Measurement Procedures, Roberto Osegueda, George R. Keller, Scott A. Starks, R. Araiza, Dm. Bizyaev, Vladik Kreinovich
Departmental Technical Reports (CS)
In many practical situations, the measurement result z depends not only on the measured value x, but also on the parameters s describing the experiment's setting and on the values of some auxiliary quantities y; the dependence z=f(x,s,y) of z on x, s, and y is usually known. In the ideal case when we know the exact value of the auxiliary parameter y, we can solve the above equation and find the desired value x. In many real-life situations, we only know y with some uncertainty, and this uncertainty leads to additional uncertainty in x.
If we are trying to …
Inside Unlv, Katrina Hudak, Carol C. Harter, James Frey
Inside Unlv, Katrina Hudak, Carol C. Harter, James Frey
Inside UNLV
No abstract provided.
Afci Quarterly Input – Unlv January Through March, 2004, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division
Afci Quarterly Input – Unlv January Through March, 2004, 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.
Proposal For No-Cost Extension And Re-Scope For Unlv Trp Project: Neutron Multiplicity Measurements For The Afci Program (Advanced Fuel Cycle Initiative), Denis Beller
Transmutation Sciences Physics (TRP)
The U.S. Advanced Fuel Cycle Initiative (AFCI) is a program to develop economic and environmental methods to reduce the impact of waste from commercial nuclear fuel cycles. One concept for near-complete destruction of waste isotopes from used nuclear fuel is accelerator-driven transmutation. High-power accelerators would be used to produce high-energy charged particles, which then collide with heavy metal targets to create a cascade of neutrons. These neutrons then cause a nuclear chain reaction in subcritical systems. Fission neutrons then transmute fissile waste isotopes as well as other problematic isotopes such as technetium-99 and iodine-129. To design these systems, complex reactor …
Santa Clara Magazine, Volume 46 Number 3, Winter 2004, Santa Clara University
Santa Clara Magazine, Volume 46 Number 3, Winter 2004, Santa Clara University
Santa Clara Magazine
8 - AN ARTIST WITH A MISSION By Elizabeth Kelley Gillogly '93. In his latest series, Howard Anderson '71 created paintings of the 21 California missions.
10 - THE SPIRITUALITY OF GIFT GIVING By Tom Beaudoin. Is it possible to turn our gift giving into a spiritual exercise?
14 - RAISING ARIZONA By Susan Shea. Arizona Governor Janet Napolitano '79, a rising political star, uses the lessons learned at SCU to serve her state.
20 - LEAVING COMMUNISM BEHIND By Jane Curry. An SCU professor and Fulbright Scholar researches forgiveness and justice in post-communist Poland.
Assessing Conceptual Models For Subsurface Reactive Transport Of Inorganic Contaminants, J.A. Davis, S.B. Yabusaki, C.I. Steefel, John M. Zachara, G.P. Curtis, G.D. Redden, L.J. Criscenti, B.D. Honeyman
Assessing Conceptual Models For Subsurface Reactive Transport Of Inorganic Contaminants, J.A. Davis, S.B. Yabusaki, C.I. Steefel, John M. Zachara, G.P. Curtis, G.D. Redden, L.J. Criscenti, B.D. Honeyman
United States Department of Energy: Publications
In many subsurface situations where human health and environmental quality are at risk (e.g., contaminant hydrogeology, petroleum extraction, carbon sequestration, etc.), scientists and engineers are being asked by federal agency decision-makers to predict the fate of chemical species under conditions where both reactions and transport are processes of first-order importance.
In 2002, a working group (WG) was formed by representatives of the U.S. Geological Survey, Environmental Protection Agency,Department of Energy,Nuclear Regulatory Commission, Department of Agriculture,and Army Engineer Research and Development Center to assess the role of reactive transport modeling (RTM) in addressing these situations. Specifically, the goals of the WG …
Understanding Manufacturing Energy Use Through Statistical Analysis, J. Kelly Kissock, John Seryak
Understanding Manufacturing Energy Use Through Statistical Analysis, J. Kelly Kissock, John Seryak
Mechanical and Aerospace Engineering Faculty Publications
Energy in manufacturing facilities is used for direct production of goods, space conditioning, and general facility support such as lighting. This paper presents a methodology for statistically analyzing plant energy use in terms of these major end uses. The methodology uses as few as 60 data points that are relatively easy for most plants to obtain. Multivariable change-point models of electricity and natural gas use as functions of outdoor air temperature and production data are then developed. The statistical models can be used to predict energy use for energy budgeting, measure savings, determine cost structures, and diagnostic purposes. Moreover, in …
Modeling Impacts On Populations: Fathead Minnow (Pimephales Promelas) Exposure To The Endocrine Disruptor 17Β-Trenbolone As A Case Study, David H. Miller, Gerald T. Ankley
Modeling Impacts On Populations: Fathead Minnow (Pimephales Promelas) Exposure To The Endocrine Disruptor 17Β-Trenbolone As A Case Study, David H. Miller, Gerald T. Ankley
United States Environmental Protection Agency: Publications
Evaluation of population-level impacts is critical to credible ecological risk assessments. In this study, a predictive model was developed to translate changes in fecundity of the fathead minnow (Pimephales promelas) in a short-term laboratory toxicity test to alterations in population growth rate. The model uniquely combines a Leslie population projection matrix and the logistic equation. Application of the model requires only a life table for the organism of interest, a measure of carrying capacity for the given population, and an estimation of the effect of a stressor on vital rates. The model was applied to investigate population dynamics …
University Of Nevada, Las Vegas Transmutation Research Program Annual Report Academic Year 2003-2004, Anthony Hechanova, Elizabeth Johnson, Gary Cerefice
University Of Nevada, Las Vegas Transmutation Research Program Annual Report Academic Year 2003-2004, Anthony Hechanova, Elizabeth Johnson, Gary Cerefice
Transmutation Research Program Reports (TRP)
It is my pleasure to present the UNLV Transmutation Research Program’s third annual report that highlights the academic year 2003 – 2004. Supporting this document are the many technical reports and scientific papers that have been generated over the past three years.
In the third year of our program, we experienced infrastructure growth despite a decreasing budget. This past year we continued into the final phases of the initial 16 independent student research tasks started in 2001 and 2002, supporting 45 graduate students and 11 undergraduates in 6 academic departments across the UNLV scientific and engineering communities during the academic …
Fundamental And Applied Experimental Investigations Of Corrosion Of Steel By Lbe Under Controlled Conditions: Kinetics, Chemistry, Morphology, And Surface Preparation: Quarterly Report, Allen L. Johnson, John Farley, Dale L. Perry
Fundamental And Applied Experimental Investigations Of Corrosion Of Steel By Lbe Under Controlled Conditions: Kinetics, Chemistry, Morphology, And Surface Preparation: Quarterly Report, Allen L. Johnson, John Farley, Dale L. Perry
Transmutation Sciences Materials (TRP)
This project has four components:
(1) the fabrication of a materials test apparatus with unique capabilities,
(2) comparative studies of steel corrosion under gas phase conditions comparable to the Lead Bismuth Eutectic (LBE) oxygen control conditions,
(3) isotope labeling studies, and
(4) collaborative efforts with other workers in the field.
Application Of Stochastic Downscaling Techniques To Global Climate Model Data For Regional Climate Prediction, Suchita Potta
Application Of Stochastic Downscaling Techniques To Global Climate Model Data For Regional Climate Prediction, Suchita Potta
LSU Master's Theses
Global warming is the most important issue of the present day that affects the climate drastically. This research was carried out to find out the effects of Global warming on Louisiana in future on a very finer spatial and temporal scale. For this purpose spatial downscaling technique is used, where finer resolution climate information is derived from a coarser resolution Global Climate Model (GCM) output. Empirical/statistical downscaling method is used in which sub grid scale changes are calculated as a function of large scale climate. For this purpose a stochastic weather generator and two Global models are considered. The two …
Afci Quarterly Input – Unlv October Through December, 2003, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division
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.
Bomb-Pulse Chlorine-36 At The Proposed Yucca Mountain Repository Horizon: An Investigation Of Previous Conflicting Results And Collection Of New Data, Klaus J. Stetzenbach, Fred Phillips, Drew Coleman, Don Baepler, Amy J. Smiecinski
Bomb-Pulse Chlorine-36 At The Proposed Yucca Mountain Repository Horizon: An Investigation Of Previous Conflicting Results And Collection Of New Data, Klaus J. Stetzenbach, Fred Phillips, Drew Coleman, Don Baepler, Amy J. Smiecinski
Publications (YM)
Previous studies by scientists at Los Alamos National Laboratory (LANL) and the United States Geological Survey (USGS) quantified 36Cl/Cl to test for the presence of fast pathways at the proposed Yucca Mountain high-level nuclear waste repository. The goal of these studies was to determine whether or not fluids containing bomb-pulse 36Cl/Cl traveled along fast travel pathways and reached the repository horizon, however, the two groups followed somewhat different procedures and produced conflicting results. The objective of this study is to attempt to determine the cause of the conflicting results and to obtain additional data to determine whether or …
Inside Unlv, Gian Galassi, Cayrn Key, Carol C. Harter, Patrick Ferrillo
Inside Unlv, Gian Galassi, Cayrn Key, Carol C. Harter, Patrick Ferrillo
Inside UNLV
No abstract provided.
Inside Unlv, Cate Weeks, Diane Russell, Carol C. Harter, Martin Watson
Inside Unlv, Cate Weeks, Diane Russell, Carol C. Harter, Martin Watson
Inside UNLV
No abstract provided.
Corrosion And Mass Transport Processes In Carbon Steel Miniature Waste Packages, James Cizdziel, Kaveh Zarrabi, Susan Lestrange, Amy J. Smiecinski
Corrosion And Mass Transport Processes In Carbon Steel Miniature Waste Packages, James Cizdziel, Kaveh Zarrabi, Susan Lestrange, Amy J. Smiecinski
Publications (YM)
In this study, we have systematically investigated corrosion and mass transport processes in carbon steel miniature waste packages (MWP) in dynamic systems (water in, water out) under varying chemical conditions. The MWP were fabricated to have similar configuration to the DOE Spent Nuclear Fuel (SNF) waste package and that individual components to be in scale with each other compare to the SNF waste package. Two MWP configurations were studied: a "bathtub" model and a "flow-through" model. By slowly dripping 4 different solutions (groundwater obtained from well water J-13 located near Yucca Mountain, and J-13 water adjusted to low-pH, high-salinity, and …
Afci Quarterly Input – Unlv July Through September, 2003, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division
Afci Quarterly Input – Unlv July Through September, 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.
Day 3. Wednesday, August 13, 2003: Lighthawk Flyover, University Of Colorado Boulder. Natural Resources Law Center
Day 3. Wednesday, August 13, 2003: Lighthawk Flyover, University Of Colorado Boulder. Natural Resources Law Center
Energy Field Tour 2003 (August 11-16)
11 pages (includes some color illustrations and maps).
Contains references.
45th Rocky Mountain Conference On Analytical Chemistry
45th Rocky Mountain Conference On Analytical Chemistry
Rocky Mountain Conference on Magnetic Resonance
Final program, abstracts, and information about the 45th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, co-endorsed by the Colorado Section of the American Chemical Society and the Rocky Mountain Section of the Society for Applied Spectroscopy. Held in Denver, Colorado, July 27-31, 2003.