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Methane Hydrates: Energy Prospect or Natural Hazard? (open access)

Methane Hydrates: Energy Prospect or Natural Hazard?

None
Date: February 14, 2000
Creator: Mielke, James E
Object Type: Report
System: The UNT Digital Library
The Administration's Lands Legacy Initiative in the FY2001 Budget Proposal - A Fact Sheet (open access)

The Administration's Lands Legacy Initiative in the FY2001 Budget Proposal - A Fact Sheet

The fact sheet compares the FY2001 funding request for the Administration's Lands Legacy Initiative to the FY2000 request and the enacted FY2000 appropriation.
Date: February 14, 2000
Creator: Zinn, Jeffrey A.
Object Type: Report
System: The UNT Digital Library
Bicycle and Pedestrian Transportation Policies (open access)

Bicycle and Pedestrian Transportation Policies

This report discusses the Bicycle and Pedestrian Legislation, Intermodal Surface Transportation Efficiency Act Of 1991 (ISTEA), Transportation Equity Act for the 21st Century,and Funding under ISTEA and TEA21.
Date: February 14, 2000
Creator: Lipford, William A. & Harrison, Glennon J.
Object Type: Report
System: The UNT Digital Library
Clean Water Action Plan: Budgetary Initiatives (open access)

Clean Water Action Plan: Budgetary Initiatives

In October 1997, Vice President Gore directed federal agencies to develop a Clean Water Initiative to improve and strengthen water pollution control efforts. The multiagency plan was released on Feb. 19, 1998, and identifies nearly 100 key actions. Most are existing activities, now labeled as part of the Initiative. The President's FY1999 budget requests $2.2 billion for five departments and agencies to fund implementation of the Plan. While Congress is considering appropriations bills to fund the Plan, federal agencies are beginning or accelerating activities to carry out the actions under the Plan.
Date: February 14, 2000
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Northern Mariana Islands: Garment and Tourist Industries Play a Dominant Role in the Commonwealth's Economy (open access)

Northern Mariana Islands: Garment and Tourist Industries Play a Dominant Role in the Commonwealth's Economy

A chapter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO provided information on the state of the economy of the Commonwealth of the Northern Mariana Islands (CNMI) and its revenue-raising efforts, focusing on: (1) what the impact of the garment and tourist industries and the use of foreign washers has been on the economy of the CNMI; (2) how the revenue-raising efforts of the CNMI and the payments that CNMI receives from the U.S. Treasury compare with those of other U.S. territories and freely associated states; and (3) how the taxes and fees paid by the garment industry in the CNMI, expressed as a percentage of gross receipts, compare with the taxes and fees paid by the garment industry in the United States."
Date: February 14, 2000
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library
On-Machine Acceptance (open access)

On-Machine Acceptance

Probing processes are used intermittently and not effectively as an on-line measurement device. This project was needed to evolve machine probing from merely a setup aid to an on-the-machine inspection system. Use of probing for on-machine inspection would significantly decrease cycle time by elimination of the need for first-piece inspection (at a remote location). Federal Manufacturing and Technologies (FM and T) had the manufacturing facility and the ability to integrate the system into production. The Contractor had a system that could optimize the machine tool to compensate for thermal growth and related error.
Date: February 14, 2000
Creator: Arnold, K. F.
Object Type: Report
System: The UNT Digital Library
Small angle X-ray scattering study of coal soot formation (open access)

Small angle X-ray scattering study of coal soot formation

The objective of this study is to examine, by small angle X-ray scattering (SAXS), the formation of soot from individual coal particle combustion in a methane flat flame burner. The SAXS instrument at the Basic Energy Sciences Synchrotron Radiation Center (BESSRC) at the Advanced Photon Source (APS) can be used to observe both the formation of spherules and clusters since it can access length scales of 6--6000 {angstrom}. The high X-ray flux enables rapid acquisition of scattering data of various regions of the flame. SAXS data reveal particle size, shape, surface areas, and surface roughness.
Date: February 14, 2000
Creator: Winans, R. E.; Parker, J. T.; Seifert, S. & Fletcher, T. H.
Object Type: Article
System: The UNT Digital Library
Support vector machines for nuclear reactor state estimation (open access)

Support vector machines for nuclear reactor state estimation

Validation of nuclear power reactor signals is often performed by comparing signal prototypes with the actual reactor signals. The signal prototypes are often computed based on empirical data. The implementation of an estimation algorithm which can make predictions on limited data is an important issue. A new machine learning algorithm called support vector machines (SVMS) recently developed by Vladimir Vapnik and his coworkers enables a high level of generalization with finite high-dimensional data. The improved generalization in comparison with standard methods like neural networks is due mainly to the following characteristics of the method. The input data space is transformed into a high-dimensional feature space using a kernel function, and the learning problem is formulated as a convex quadratic programming problem with a unique solution. In this paper the authors have applied the SVM method for data-based state estimation in nuclear power reactors. In particular, they implemented and tested kernels developed at Argonne National Laboratory for the Multivariate State Estimation Technique (MSET), a nonlinear, nonparametric estimation technique with a wide range of applications in nuclear reactors. The methodology has been applied to three data sets from experimental and commercial nuclear power reactor applications. The results are promising. The combination of …
Date: February 14, 2000
Creator: Zavaljevski, N. & Gross, K. C.
Object Type: Article
System: The UNT Digital Library
Line of Sight: A process for transferring science from the laboratory to the market place (open access)

Line of Sight: A process for transferring science from the laboratory to the market place

Commercialization and transfer of technology from laboratories in academia, government, and industry has only met a fraction of its potential and is currently an art not a science. The line of sight approach developed and in use at Sandia National Laboratories, is used to better understand commercialization and transfer of technology. The line of sight process integrates technology description, the dual process model of innovation and the product introduction model. The model, that the line of sight is based OR is presented and the application of the model to both disruptive and sustaining technologies is illustrated. Work to date suggests that the differences between disruptive and sustaining technologies are critical to quantifying the level of risk and choosing the commercialization path. The applicability of the line of sight to both disruptive and sustaining technologies is key to the success of the model and approach.
Date: February 14, 2000
Creator: Linton, Jonathan; Walsh, Steven; Lombana, Cesar A.; Hunter, Willard, B. & Romig Jr., Alton D.
Object Type: Article
System: The UNT Digital Library
Pressure as a probe of the physics of ABO{sub 3} relaxor ferroelectrics (open access)

Pressure as a probe of the physics of ABO{sub 3} relaxor ferroelectrics

Results on a variety of mixed ABO{sub 3} oxides have revealed a pressure-induced ferroelectric-to-relaxor crossover and the continuous evolution of the energetics and dynamics of the relaxation process with increasing pressure. These common features have suggested a mechanism for the crossover phenomenon in terms of a large decrease in the correlation length for dipolar interactions with pressure--a unique property of soft mode or highly polarizable host lattices. The pressure effects as well as the interplay between pressure and dc biasing fields are illustrated for some recent results on PZN-9.5 PT,PMN and PLZT 6/65/35.
Date: February 14, 2000
Creator: SAMARA,GEORGE A.
Object Type: Article
System: The UNT Digital Library
Nature, strength, and consequences of indirect adsorbate interactions on metals (open access)

Nature, strength, and consequences of indirect adsorbate interactions on metals

Atoms and molecules adsorbed on metals affect each other even over considerable distances. In a tour-de-force of density-functional methods, the authors establish the nature and strength of such indirect interactions, and explain for what adsorbate systems they can critically affect important materials properties. These perceptions are verified in kinetic Monte Carlo simulations of epitaxial growth, and help rationalize a cascade of recent experimental reports on anomalously low diffusion prefactors. The authors focus their study on two metal systems: Al/Al(111) and Cu/Cu(111).
Date: February 14, 2000
Creator: Bogicevic, Alexander; Ovesson, S.; Hyldgaard, P.; Lundqvist, B. I. & Jennison, Dwight R.
Object Type: Article
System: The UNT Digital Library
EMS IMPLEMENTATION COSTS AT A DOE NATIONAL LABORATORY (open access)

EMS IMPLEMENTATION COSTS AT A DOE NATIONAL LABORATORY

None
Date: February 14, 2000
Creator: BRIGGS,S.L.K.
Object Type: Article
System: The UNT Digital Library
Building integrated PV for commercial and institutional structures, a sourcebook for architects (open access)

Building integrated PV for commercial and institutional structures, a sourcebook for architects

This sourcebook on building-integrated photovoltaics (BIPV) is intended for architects and designers interested in learning more about today's sustainable solar buildings. The booklet includes 16 design briefs describing actual structures; they illustrate how electricity-generating BIPV products (such as special roofing systems, vertical-wall systems, skylights, and awnings, all of which contain PV cells, modules, and films) can be integrated successfully into many different kinds of buildings. It also contains basic information about BIPV technologies, an overview of US product development activities and development programs, descriptions of major software design tools, and a bibliography.
Date: February 14, 2000
Creator: Eiffert, P. & Kiss, G.
Object Type: Book
System: The UNT Digital Library
The generation of hexahedral meshes for assembly geometries: A survey (open access)

The generation of hexahedral meshes for assembly geometries: A survey

The finite element method is being used today to model component assemblies in a wide variety of application areas, including structural mechanics, fluid simulations, and others. Generating hexahedral meshes for these assemblies usually requires the use of geometry decomposition, with different meshing algorithms applied to different regions. While the primary motivation for this approach remains the lack of an automatic, reliable all-hexahedral meshing algorithm, requirements in mesh quality and mesh configuration for typical analyses are also factors. For these reasons, this approach is also sometimes required when producing other types of unstructured meshes. This paper will review progress to date in automating many parts of the hex meshing process, which has halved the time to produce all-hex meshes for large assemblies. Particular issues which have been exposed due to this progress will also be discussed, along with their applicability to the general unstructured meshing problem.
Date: February 14, 2000
Creator: TAUTGES,TIMOTHY J.
Object Type: Article
System: The UNT Digital Library
Predicted performance of neutron spectrometers using scintillating fibers (open access)

Predicted performance of neutron spectrometers using scintillating fibers

A variety of needs exists for knowing the energy spectral content of a neutron flux. Among these needs are arms-control and national-security applications, which arise because different neutron sources produce different neutron energy spectra. This work is primarily directed at these applications. The concept described herein is a spectrometer in the same sense as a Bonner sphere. The instrument response reflects a statistical average of the energy spectrum. The Bonner sphere is an early rendition of this class. In this, a neutron detector is placed at the center of a moderating (and absorbing) sphere (of varying thickness and composition). Spectral unfolding is required, and the resolution and efficiency are, typically, poor, although the potential bandwidth is very large. A recent variation on the Bonner-sphere approach uses {sup 3}He gas proportional counters with resistive wires to locate the position of the event (Toyokawa et al 1996). The spectrometer concept investigated here has the potential for better resolution and much improved neutron efficiency compared to Bonner spheres and similar devices. These improvements are possible because of the development of neutron-sensitive, scintillating-glass fibers. These fibers can be precisely located in space, which allows a corresponding precision in energy resolution. Also, they can be …
Date: February 14, 2000
Creator: Craig, RA & Bliss, M
Object Type: Report
System: The UNT Digital Library
Electron-impact ionization of atomic hydrogen (open access)

Electron-impact ionization of atomic hydrogen

Since the invention of quantum mechanics, even the simplest example of collisional breakup in a system of charged particles, e{sup {minus}} + H {r_arrow} H{sup +} + e{sup {minus}} + e{sup {minus}}, has stood as one of the last unsolved fundamental problems in atomic physics. A complete solution requires calculating the energies and directions for a final state in which three charged particles are moving apart. Advances in the formal description of three-body breakup have yet to lead to a viable computational method. Traditional approaches, based on two-body formalisms, have been unable to produce differential cross sections for the three-body final state. Now, by using a mathematical transformation of the Schrodinger equation that makes the final state tractable, a complete solution has finally been achieved, Under this transformation, the scattering wave function can be calculated without imposing explicit scattering boundary conditions. This approach has produced the first triple differential cross sections that agree on an absolute scale with experiment as well as the first ab initio calculations of the single differential cross section.
Date: February 14, 2000
Creator: Baertschy, Mark D.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Qualification of uranium-molybdenum alloy fuel -- conclusions of an international workshop (open access)

Qualification of uranium-molybdenum alloy fuel -- conclusions of an international workshop

Thirty-one participants representing 21 reactors, fuel developers, fuel fabricators, and fuel reprocessors in 11 countries discussed the requirements for qualification of U-MO alloy fuel at a workshop held at Argonne National Laboratory on January 17--18, 2000. Consensus was reached that the qualification plans of the US RERTR program and the French U-Mo fuel development program are valid. The items to be addressed during qualification are summarized in the paper.
Date: February 14, 2000
Creator: Snelgrove, J. L. & Languilee, A.
Object Type: Article
System: The UNT Digital Library
A spray-suppression model for turbulent combustion (open access)

A spray-suppression model for turbulent combustion

A spray-suppression model that captures the effects of liquid suppressant on a turbulent combusting flow is developed and applied to a turbulent diffusion flame with water spray suppression. The spray submodel is based on a stochastic separated flow approach that accounts for the transport and evaporation of liquid droplets. Flame extinguishment is accounted for by using a perfectly stirred reactor (PSR) submodel of turbulent combustion. PSR pre-calculations of flame extinction times are determined using CHEMKIN and are compared to local turbulent time scales of the flow to determine if local flame extinguishment has occurred. The PSR flame extinguishment and spray submodels are incorporated into Sandia's flow fire simulation code, VULCAN, and cases are run for the water spray suppression studies of McCaffrey for turbulent hydrogen-air jet diffusion flames. Predictions of flame temperature decrease and suppression efficiency are compared to experimental data as a function of water mass loading using three assumed values of drop sizes. The results show that the suppression efficiency is highly dependent on the initial droplet size for a given mass loading. A predicted optimal suppression efficiency was observed for the smallest class of droplets while the larger drops show increasing suppression efficiency with increasing mass loading …
Date: February 14, 2000
Creator: Desjardin, Paul E.; Tieszen, Sheldon R. & Gritzo, Louis A.
Object Type: Article
System: The UNT Digital Library
The optimum Cs condition for high-resolution transmission electron microscopy (open access)

The optimum Cs condition for high-resolution transmission electron microscopy

With the advent of electron-optical systems able to generate negative spherical aberration (usually called ''Cs correctors''), it has now become feasible to zero-out objective lens Cs in the high-resolution transmission electron microscope. However, I show that - instead of tuning out spherical aberration completely - there is an optimum value for the residual Cs that maximizes information transfer to the best possible resolution and depends only on the information limit of the microscope.
Date: February 14, 2000
Creator: O'Keefe, Michael A.
Object Type: Article
System: The UNT Digital Library
Predicted Performance of Neutron Spectrometers Using Scintillating Fibers (open access)

Predicted Performance of Neutron Spectrometers Using Scintillating Fibers

One class of neutron spectrometers is devices that provide a measure of the neutron spectrum by using moderating and absorbing materials together with thermal-neutron detectors. Pacific Northwest National Laboratory has developed scintillating fibers that are sensitive to thermal neutrons. Because these fibers are thin, they present an enabling technology for several applications, including highly efficient neutron spectroscopy. The underlying concept is to arrange the fibers in an array of layers separated by materials whose characteristics have been chosen to optimize the instrument function for the application. Monte Carlo experiments have been performed to characterize the conceptual design and to determine the value of the concept as a tool for research and other applications.
Date: February 14, 2000
Creator: Craig, Richard A & Bliss, Mary
Object Type: Report
System: The UNT Digital Library
Cartesian Methods for the Shallow Water Equations on a Sphere (open access)

Cartesian Methods for the Shallow Water Equations on a Sphere

The shallow water equations in a spherical geometry are solved using a 3-dimensional Cartesian method. Spatial discretization of the 2-dimensional, horizontal differential operators is based on the Cartesian form of the spherical harmonics and an icosahedral (spherical) grid. Computational velocities are expressed in Cartesian coordinates so that a problem with a singularity at the pole is avoided. Solution of auxiliary elliptic equations is also not necessary. A comparison is made between the standard form of the Cartesian equations and a rotational form using a standard set of test problems. Error measures and conservation properties of the method are reported for the test problems.
Date: February 14, 2000
Creator: Drake, J.B.
Object Type: Report
System: The UNT Digital Library
Final progress report, Construction of a genome-wide highly characterized clone resource for genome sequencing (open access)

Final progress report, Construction of a genome-wide highly characterized clone resource for genome sequencing

At TIGR, the human Bacterial Artificial Chromosome (BAC) end sequencing and trimming were with an overall sequencing success rate of 65%. CalTech human BAC libraries A, B, C and D as well as Roswell Park Cancer Institute's library RPCI-11 were used. To date, we have generated >300,000 end sequences from >186,000 human BAC clones with an average read length {approx}460 bp for a total of 141 Mb covering {approx}4.7% of the genome. Over sixty percent of the clones have BAC end sequences (BESs) from both ends representing over five-fold coverage of the genome by the paired-end clones. The average phred Q20 length is {approx}400 bp. This high accuracy makes our BESs match the human finished sequences with an average identity of 99% and a match length of 450 bp, and a frequency of one match per 12.8 kb contig sequence. Our sample tracking has ensured a clone tracking accuracy of >90%, which gives researchers a high confidence in (1) retrieving the right clone from the BA C libraries based on the sequence matches; and (2) building a minimum tiling path of sequence-ready clones across the genome and genome assembly scaffolds.
Date: February 14, 2000
Creator: Nierman, William C.
Object Type: Report
System: The UNT Digital Library
Distributed Denial of Service Tools, Trin00, Tribe Flood Network, Tribe Flood Network 2000 and Stacheldraht. (open access)

Distributed Denial of Service Tools, Trin00, Tribe Flood Network, Tribe Flood Network 2000 and Stacheldraht.

One type of attack on computer systems is know as a Denial of Service (DoS) attack. A DoS attack is designed to prevent legitimate users from using a system. Traditional Denial of Service attacks are done by exploiting a buffer overflow, exhausting system resources, or exploiting a system bug that results in a system that is no longer functional. In the summer of 1999, a new breed of attack has been developed called Distributed Denial of Service (DDoS) attack. Several educational and high capacity commercial sites have been affected by these DDoS attacks. A DDoS attack uses multiple machines operating in concert to attack a network or site. There is very little that can be done if you are the target of a DDoS. The nature of these attacks cause so much extra network traffic that it is difficult for legitimate traffic to reach your site while blocking the forged attacking packets. The intent of this paper is to help sites not be involved in a DDoS attack. The first tools developed to perpetrate the DDoS attack were Trin00 and Tribe Flood Network (TFN). They spawned the next generation of tools called Tribe Flood Network 2000 (TFN2K) and Stacheldraht (German …
Date: February 14, 2000
Creator: Criscuolo, P. J.
Object Type: Report
System: The UNT Digital Library
Planning Document for Spent Nuclear Fuel (SNF) Cleanliness Inspection Process (OCRWM) (open access)

Planning Document for Spent Nuclear Fuel (SNF) Cleanliness Inspection Process (OCRWM)

The Fuel Retrieval System (FRS) Process Validation Procedure (Shen 1999) requires that a specified quantity of fuel processed through the Primary Cleaning Machine (PCM) be inspected for cleanliness during initial operational and process validation testing. Specifically, these inspections are performed to confirm that the PCM adequately cleans the fuel elements of canister sludge. The results of these inspections will be used to demonstrate that residual quantities of canister particulate on fuel elements loaded into Multi-Canister Overpacks (MCOs) are within projected levels used to establish safety basis limits (Sloughter 1998). The fuel inspections performed as part of the validation process will be conducted during the Hot Operations portion of the Phased Startup Initiative (PSI) of the Fuel Retrieval and Integrated Water Treatment Systems (Pajunen 1999). Hot Operations testing constitutes Phases 3 and 4 of the PSI. The fuel assemblies in all candidate canisters will be thoroughly inspected during these test phases (highly degraded fuel assemblies are exempt from inspection). During subsequent production operation of the FRS, only periodic (every tenth canister) inspections for cleanliness will be performed and documented. This document describes the specific processes and techniques that will be applied in performing the cleanliness inspections, and the methodology used to …
Date: February 14, 2000
Creator: Pitner, A. L.
Object Type: Report
System: The UNT Digital Library