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Community-oriented policing in a multicultural milieu: the case of loitering and disorderly conduct in East Arlington, Texas (open access)

Community-oriented policing in a multicultural milieu: the case of loitering and disorderly conduct in East Arlington, Texas

Article on community-oriented policing in a multicultural milieu and the case of loitering and disorderly conduct in East Arlington.
Date: September 20, 2002
Creator: Eve, Raymond A., 1946-; Rodeheaver, Daniel Gilbert, 1954-; Eve, Susan Brown; Hockenberger, Maureen; Pérez, Ramona L.; Burton, Ken et al.
System: The UNT Digital Library
Non-darcy flow behavior mean high-flux injection wells in porous and fractured formations (open access)

Non-darcy flow behavior mean high-flux injection wells in porous and fractured formations

This paper presents a study of non-Darcy fluid flow through porous and fractured rock, which may occur near wells during high-flux injection of waste fluids into underground formations. Both numerical and analytical models are used in this study. General non-Darcy flow is described using the Forchheimer equation, implemented in a three-dimensional, multiphase flow reservoir simulator. The non-Darcy flow through a fractured reservoir is handled using a general dual continuum approach, covering commonly used conceptual models, such as double porosity, dual permeability, explicit fracture, etc. Under single-phase flow conditions, an approximate analytical solution, as an extension of the Warren-Root solution, is discussed. The objectives of this study are (1) to obtain insights into the effect of non-Darcy flow on transient pressure behavior through porous and fractured reservoirs and (2) to provide type curves for well test analyses of non-Darcy flow wells. The type curves generated include various types of drawdown, injection, and buildup tests with non-Darcy flow occurring in porous and fractured reservoirs. In addition, non-Darcy flow into partially penetrating wells is also considered. The transient-pressure type curves for flow in fractured reservoirs are based on the double-porosity model. Type curves provided in this work for non-Darcy flow in porous and …
Date: April 25, 2003
Creator: Wu, Yu-Shu
System: The UNT Digital Library
First D-Zero jet measurements at squareroot s =1.96 TeV (open access)

First D-Zero jet measurements at squareroot s =1.96 TeV

The authors present the first Run II measurements with the D0 detector of the inclusive jet and dijet cross sections at {radical}s = 1.96 TeV. This analysis is based on an integrated luminosity of 34 pb{sup -1}. The results from a next-to-leading order perturbative QCD calculation are compared to the measured cross sections. The theoretical calculation agrees with the data.
Date: September 25, 2003
Creator: Begel, Michael
System: The UNT Digital Library
Charged current disappearance measurements in the NuMI off-axis beam (open access)

Charged current disappearance measurements in the NuMI off-axis beam

This article studies the potential of combining charged-current disappearance measurements of {nu}{sub {mu}} {yields} {nu}{sub {tau}} from MINOS and an off-axis beam. The author finds that the error on {Delta}m{sup 2} from a 100 kt-yr off-axis measurement is a few percent of itself. Further, the author found little improvement to an off-axis measurement by combining it with MINOS.
Date: September 25, 2003
Creator: Bernstein, R. H.
System: The UNT Digital Library
The second moment of the pion light cone wave function (open access)

The second moment of the pion light cone wave function

We present a preliminary result for second moment of the light cone wave function of the pion. This parameter is the subject of a discrepancy between theoretical predictions (coming from lattice and sum rules) and a recent experimental result (that remarkably agrees with purely perturbative predictions). In this work we exploit lattice hypercubic symmetries to remove power divergences and, moreover, implement a full 1-loop matching for all the contributing operators.
Date: September 25, 2003
Creator: Debbio, Luigi del; Pierro, Massimo di & Dougall, Alex
System: The UNT Digital Library
First observation of doubly charmed baryons (open access)

First observation of doubly charmed baryons

The SELEX experiment (E781) at Fermilab has observed two statistically compelling high mass states near 3.6 GeV/c{sup 2}, decaying to {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +} and {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +}{pi}{sup +}. These final states are Cabibbo-allowed decay modes of doubly charmed baryons {Xi}{sub cc}{sup +} and {Xi}{sub cc}{sup ++}, respectively. The masses are in the range expected from theoretical considerations, but the spectroscopy is surprising. SELEX also has weaker preliminary evidence for a state near 3.8 GeV/c{sup 2}, a high mass state decaying to {Lambda}{sub c}{sup +} K{sup -} {pi}{sup +}{pi}{sup +}, possibly an excited {Xi}{sub cc}{sup ++} (ccu*). Data are presented and discussed.
Date: September 25, 2003
Creator: al., M. A. Moinester et
System: The UNT Digital Library
HEU Measurements of Holdup and Recovered Residue in the Deactivation and Decommission Activities of the 321-M Reactor Fuel Fabrication Facility at the Savannah River Site (open access)

HEU Measurements of Holdup and Recovered Residue in the Deactivation and Decommission Activities of the 321-M Reactor Fuel Fabrication Facility at the Savannah River Site

This paper contains a summary of the holdup and material control and accountability assays conducted for the determination of highly enriched uranium in the deactivation and decommissioning of Building 321 -M at the Savannah River Site. The facility was the Reactor Fuel Fabrication Facility at SRS and assemblies and miscellaneous components for the SRS production reactors. The facility operated for 25 years. During this time thousands of uranium-aluminum-alloy production reactor fuel tubes were produced. After the facility ceased operations in 1995, all of the easily accessible U-Al was removed from the building, and only residual amounts remained. The D and D project is likely to represent an important example for D and D activities across SRS and across the Department of Energy weapons complex.
Date: June 25, 2003
Creator: Dewberry, R.
System: The UNT Digital Library
TMVOC, simulator for multiple volatile organic chemicals (open access)

TMVOC, simulator for multiple volatile organic chemicals

TMVOC is a numerical simulator for three-phase non-isothermal flow of water, soil gas, and a multicomponent mixture of volatile organic chemicals (VOCs) in multidimensional heterogeneous porous media. It is an extension of the TOUGH2 general-purpose simulation program developed at the Lawrence Berkeley National Laboratory. TMVOC is designed for applications to contamination problems that involve hydrocarbon fuel or organic solvent spills in saturated and unsaturated zones. It can model contaminant behavior under ''natural'' environmental conditions, as well as for engineered systems, such as soil vapor extraction, groundwater pumping, or steam-assisted source remediation. TMVOC is upwards compatible with T2VOC (Falta et al., 1995) and can be initialized from T2VOC-style initial conditions. The main enhancements in TMVOC relative to T2VOC are as follows: a multicomponent mixture of volatile organic chemicals can be modeled; any and all combinations of the three phases water-oil-gas are treated; several non-condensible gases may be present; diffusion is treated in all phases in a manner that is fully coupled with phase partitioning. This paper gives a brief summary of the methodology used in TMVOC as well as highlighting some implementation issues. Simulation of a NAPL spill and subsequent remediation is discussed for a 2-D vertical section of a saturated-unsaturated …
Date: March 25, 2003
Creator: Pruess, Karsten & Battistelli, Alfredo
System: The UNT Digital Library
Reconstruction of fundamental SUSY parameters (open access)

Reconstruction of fundamental SUSY parameters

We summarize methods and expected accuracies in determining the basic low-energy SUSY parameters from experiments at future e{sup +}e{sup -} linear colliders in the TeV energy range, combined with results from LHC. In a second step we demonstrate how, based on this set of parameters, the fundamental supersymmetric theory can be reconstructed at high scales near the grand unification or Planck scale. These analyses have been carried out for minimal supergravity [confronted with GMSB for comparison], and for a string effective theory.
Date: September 25, 2003
Creator: al., P. M. Zerwas et
System: The UNT Digital Library
Innovative Flash Control in Inertia Welding (open access)

Innovative Flash Control in Inertia Welding

Inertia welding is widely used to join cylindrically shaped objects such as disks and shafts in turbine engines, turbochargers, etc. Flash control in many of these applications is not critical because the excess material is on external surfaces and can readily be removed by machining. Internal flash on hollow vessels, however, may be difficult or impossible to remove and may be either controlled by the use of flash traps or the part can be used as welded. Both internal flash and flash traps reduce internal volume and the conditions are not always acceptable. To address this short-coming, several innovative methods have been tested to determine their effect on flash control in inertia welding of hollow vessels. The methods include introduction of high pressure inert gas and incorporation of an expendable mandrel to divert the flash. Both gas and internal mandrels appear promising methods for diverting flash.
Date: April 25, 2003
Creator: Korinko, P.S.
System: The UNT Digital Library
Sfermion precision measurements at a linear collider (open access)

Sfermion precision measurements at a linear collider

At future e{sup +}e{sup -} linear colliders, the event rates and clean signals of scalar fermion production--in particular for the scalar leptons--allow very precise measurements of their masses and couplings and the determination of their quantum numbers. Various methods are proposed for extracting these parameters from the data at the sfermion thresholds and in the continuum. At the same time, NLO radiative corrections and non-zero width effects have been calculated in order to match the experimental accuracy. The substantial mixing expected for the third generation sfermions opens up additional opportunities. Techniques are presented for determining potential CP-violating phases and for extracting tan {beta} from the stau sector, in particular at high values. The consequences of possible large mass differences in the stop and sbottom system are explored in dedicated analyses.
Date: September 25, 2003
Creator: al., A. Freitas et
System: The UNT Digital Library
The transforming activity of Ski is dependent on its ability to repress the activity of Smad proteins (open access)

The transforming activity of Ski is dependent on its ability to repress the activity of Smad proteins

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Date: June 25, 2003
Creator: He, Jun; Tegen, Sarah B.; Krawitz, Ariel R.; Martin, G. Steven & Luo, Kunxin
System: The UNT Digital Library
An evaluation of current high-performance networks (open access)

An evaluation of current high-performance networks

High-end supercomputers are increasingly built out of commodity components, and lack tight integration between the processor and network. This often results in inefficiencies in the communication subsystem, such as high software overheads and/or message latencies. In this paper we use a set of microbenchmarks to quantify the cost of this commoditization, measuring software overhead, latency, and bandwidth on five contemporary supercomputing networks. We compare the performance of the ubiquitous MPI layer to that of lower-level communication layers, and quantify the advantages of the latter for small message performance. We also provide data on the potential for various communication-related optimizations, such as overlapping communication with computation or other communication. Finally, we determine the minimum size needed for a message to be considered 'large' (i.e., bandwidth-bound) on these platforms, and provide historical data on the software overheads of a number of supercomputers over the past decade.
Date: January 25, 2003
Creator: Bell, Christian; Bonachea, Dan; Cote, Yannick; Duell, Jason; Hargrove, Paul; Husbands, Parry et al.
System: The UNT Digital Library
Beam tests of ionization chambers for the NuMI neutrino beam (open access)

Beam tests of ionization chambers for the NuMI neutrino beam

We have conducted tests at the Fermilab Booster of ionization chambers to be used as monitors of the NuMI neutrino beamline. The chambers were exposed to proton fluxes of up to 10{sup 12} particles/cm{sup 2}/1.56 {micro}s. We studied space charge effects which can reduce signal collection from the chambers at large charged particle beam intensities.
Date: September 25, 2003
Creator: al., Robert M. Zwaska et
System: The UNT Digital Library
Variability in energy factor test results for residential electric water heaters (open access)

Variability in energy factor test results for residential electric water heaters

Recent modifications to the minimum energy efficiency requirements for residential water heaters have spurred an investigation into the variability in testing high-efficiency electric water heaters. While initial inter-laboratory comparisons showed excellent agreement between test results from different labs, subsequent inter-laboratory comparisons show differences between measured energy factors of up to 0.040. To determine the source of these differences, analyses of various parts of the test procedure are performed. For one case studied, the uncertainty in test results can be as high as +-0.028 if instrument accuracies reach the minimum level allowed in the test procedure. Other areas of the test procedure where variability is introduced are the optional use of pre-draws, the location of the lower tank temperature-measuring device, the use of insulation on tank fittings, and the use of a warm-up period before the simulated-use test commences. The implications of these issues on test results are provided.
Date: April 25, 2003
Creator: Healy, William; Lutz, James D. & Lekov, Alex
System: The UNT Digital Library
Simulation of a Batch Chemical Process Using Parallel Computing with PVM and Speedup (open access)

Simulation of a Batch Chemical Process Using Parallel Computing with PVM and Speedup

Speedup, a commercial software package for the dynamic modeling of chemical processes, has been coupled with the PVM software to allow a single process model to be distributed over several computers running in parallel. As an initial application, this coarse distribution technique was applied to a batch chemical plant containing 16 unit operations. Computation time for this problem was reduced by a factor of 4.7 using only three parallel processors in the UNIX computing environment. Better than linear acceleration was achieved from the significant reduction in computation required to reinitialize the smaller subprocesses at discontinuities in the solution. The process was physically divided at points that naturally separated the overall plant into distinct subprocesses. This facilitated the computation by minimizing the interconnection between the parallel units. Techniques were developed to make efficient material and energy transfers between the modeled subprocesses based on actual material transfers used in plant operations.
Date: March 25, 2003
Creator: Smith, F. G., III
System: The UNT Digital Library
Protection of Nuclear Plants Against Vehicular Bombs Via Full Spectrum Risk Assessment (open access)

Protection of Nuclear Plants Against Vehicular Bombs Via Full Spectrum Risk Assessment

A more urgent need now exists since 9/11 to protect vital assets at nuclear plants from physical security threats. Any approach to successful defense must result in the best possible risk profile , while also performing this defense against credible threats within the context of limited personnel and materiel resources. Engineered solutions need to be well thought out, and take advantage of each plant's available organic strengths and opportunities. A robust, well trained/equipped highly motivated protective force will help reduce concerns where there are weaknesses making the plant vulnerable to threats. A thorough risk assessment takes into account the proper combination of both deterministic and probabilistic application of resources as a most advantageous approach; this is postulated to be development of integrated protection methods and plans, which blend solid engineering design with the highest caliber of protection forces. By setting a clear and ambitious objective to shield the nuclear assets with this type of dynamic full spectrum defense in depth, the risk of harm-breach or likelihood of any opponent's threat being realized should be reduced to the lowest practicable levels.
Date: February 25, 2003
Creator: Campagna, M. S. & Sawruk, W.
System: The UNT Digital Library
Spent Fuel Reprocessing: More Value for Money Spent in a Geological Repository? (open access)

Spent Fuel Reprocessing: More Value for Money Spent in a Geological Repository?

Today, each utility or country operating nuclear power plants can select between two long-term spent fuel management policies: either, spent fuel is considered as waste to dispose of through direct disposal or, spent fuel is considered a resource of valuable material through reprocessing-recycling. Reading and listening to what is said in the nuclear community, we understand that most people consider that the choice of policy is, actually, a choice among two technical paths to handle spent fuel: direct disposal versus reprocessing. This very simple situation has been recently challenged by analysis coming from countries where both policies are on survey. For example, ONDRAF of Belgium published an interesting study showing that, economically speaking for final disposal, it is worth treating spent fuel rather than dispose of it as a whole, even if there is no possibility to recycle the valuable part of it. So, the question is raised: is there such a one-to-one link between long term spent fuel management political option and industrial option? The purpose of the presentation is to discuss the potential advantages and drawbacks of spent fuel treatment as an implementation of the policy that considers spent fuel as waste to dispose of. Based on technical …
Date: February 25, 2003
Creator: Kaplan, P.; Vinoche, R.; Devezeaux, J-G. & Bailly, F.
System: The UNT Digital Library
Problems Encountered During the Radiological Remediation of Old Buildings (open access)

Problems Encountered During the Radiological Remediation of Old Buildings

With several military base closures resulting in property transfer to public use and the decommissioning of many legacy waste facilities, the opportunity for remediation of older buildings is increasing. Along with these projects, come several problems that could give the potential remediator some surprises. During the preconstruction and planning phases of the original construction activities, several generations of drawings were most likely produced for approval and permit submittal. Over the years, buildings may undergo several renovations with or without the full characterization or remediation that should be done when radioactive materials are used on a site. New walls or floors may be built over the original construction materials. Contamination in and around the building may have resulted from processes that were accepted at the time or from inadvertent activities that may have been covered up, including accidental spills. Many buildings contain hidden rooms or accesses that over time became useless and have been closed up or over, these areas may not be very obvious. When characterizing a building the effluents of the building are usually forgotten, sewer lines are important areas to investigate. All these items could cause a remediator to overlook a potentially highly contaminated area. With more of …
Date: February 25, 2003
Creator: Krieger, K. V. & Schillings, D. C.
System: The UNT Digital Library
National Ambient Radiation Database (open access)

National Ambient Radiation Database

The U.S. Environmental Protection Agency (EPA) recently developed a searchable database and website for the Environmental Radiation Ambient Monitoring System (ERAMS) data. This site contains nationwide radiation monitoring data for air particulates, precipitation, drinking water, surface water and pasteurized milk. This site provides location-specific as well as national information on environmental radioactivity across several media. It provides high quality data for assessing public exposure and environmental impacts resulting from nuclear emergencies and provides baseline data during routine conditions. The database and website are accessible at www.epa.gov/enviro/. This site contains (1) a query for the general public which is easy to use--limits the amount of information provided, but includes the ability to graph the data with risk benchmarks and (2) a query for a more technical user which allows access to all of the data in the database, (3) background information on ER AMS.
Date: February 25, 2003
Creator: Dziuban, J. & Sears, R.
System: The UNT Digital Library
Washing of Cloth Contaminated with Radionuclides Using A Detergent-Free Laundry System (open access)

Washing of Cloth Contaminated with Radionuclides Using A Detergent-Free Laundry System

In this study, we describe a new laundry system to wash clothes, including those contaminated with radionuclides, without using detergent. The main part of this system is electrolytic cell that consists of a cathode with a special coating of nickel, an anode of nickel, and a cation exchange membrane between the two electrodes. The electrolyte is supplied to the anode and the tap-water to the cathode. When an electricity of 5 volts and 25 amperes is applied to the electrodes, the processed water is produced from the cathode. This processed water containing no detergent was investigated experimentally with regard to its decontamination efficiency of radionuclides and detergency of soil as compared to the conventional washing using detergent. It was found that the processed water from this system has an ability to simultaneously remove radionuclides and soil from the cloth with good efficiency.
Date: February 25, 2003
Creator: Yim, S. P.; Ahn, B. G.; Lee, H. J.; Shon, J. S.; Chung, H.; Kim, K. J. et al.
System: The UNT Digital Library
Treatment of Organic-Contaminated Mixed Waste Utilizing the Oak Ridge Broad Spectrum Contracts (open access)

Treatment of Organic-Contaminated Mixed Waste Utilizing the Oak Ridge Broad Spectrum Contracts

To meet the requirements of the State of Tennessee's Department of Environment and Conservation Commissioner's Order for treatment of mixed low level wastes, Oak Ridge has utilized commercial treatment companies to treat and dispose mixed waste. Over the past year, Oak Ridge has shipped organic-contaminated mixed waste for treatment to meet milestones under the Site Treatment Plan. Oak Ridge has established contracts with commercial treatment companies accessible by all DOE sites for treatment of a wide range of mixed wastes. The paper will describe and summarize the activities involved in treating and disposing of organic-contaminated mixed waste utilizing DOE complex-wide contracts and the treatment and disposal activities required. This paper will describe the case history of treatment of several organic-contaminated mixed wastes from the Oak Ridge Reservation requiring treatment prior to disposal. The paper will include waste category information, implementation activities, and contract access. The paper will discuss the specifics of the mixed waste treatment including waste characteristics, treatment process and equipment utilized, and treatment results. Additional information will be provided on task order development, waste profiling, treatment pricing, and the disposal process.
Date: February 25, 2003
Creator: Estes, C. H.; Heacker, F. K.; Cunningham, J. & Westich, B.
System: The UNT Digital Library
Studsvik Processing Facility Update (open access)

Studsvik Processing Facility Update

Studsvik has completed over four years of operation at its Erwin, TN facility. During this time period Studsvik processed over 3.3 million pounds (1.5 million kgs) of radioactive ion exchange bead resin, powdered filter media, and activated carbon, which comprised a cumulative total activity of 18,852.5 Ci (6.98E+08 MBq). To date, the highest radiation level for an incoming resin container has been 395 R/hr (3.95 Sv/h). The Studsvik Processing Facility (SPF) has the capability to safely and efficiently receive and process a wide variety of solid and liquid Low Level Radioactive Waste (LLRW) streams including: Ion Exchange Resins (IER), activated carbon (charcoal), graphite, oils, solvents, and cleaning solutions with contact radiation levels of up to 400 R/hr (4.0 Sv/h). The licensed and heavily shielded SPF can receive and process liquid and solid LLRWs with high water and/or organic content. This paper provides an overview of the last four years of commercial operations processing radioactive LLRW from commercial nuclear power plants. Process improvements and lessons learned will be discussed.
Date: February 25, 2003
Creator: Mason, J. B.; Oliver, T. W.; Hill, G. M.; Davin, P. F. & Ping, M. R.
System: The UNT Digital Library
The Waste Isolation Pilot Plant: An International Center of Excellence (open access)

The Waste Isolation Pilot Plant: An International Center of Excellence

The United States Department of Energy's Carlsbad Field Office (CBFO) is responsible for the successful management of transuranic radioactive waste (TRUW) in the United States. TRUW is a long-lived radioactive waste/material (LLRM). CBFO's responsibilities includes the operation of the Waste Isolation Pilot Plant (WIPP), which is a deep geologic repository for the safe disposal of U.S. defense-related TRUW and is located 42 kilometers (km) east of Carlsbad, New Mexico. WIPP is the only deep-geological disposal site for LLRM that is operating in the world today. CBFO also manages the National Transuranic Waste Program (NTP), which oversees TRU waste management from generation to disposal. As of February 2003, approximately 1500 shipments of waste have been safely transported to the WIPP, which has been operating since March 1999.
Date: February 25, 2003
Creator: Matthews, Mark
System: The UNT Digital Library