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Modeling of Fission Neutrons as a Signature for Detection of Highly Enriched Uranium (open access)

Modeling of Fission Neutrons as a Signature for Detection of Highly Enriched Uranium

We present the results of modeling intended to evaluate the feasibility of using neutrons from induced fission in highly enriched uranium (HEU) as a means of detecting clandestine HEU, even when it is embedded in absorbing surroundings, such as commercial cargo. We characterized radiation from induced fission in HEU, which consisted of delayed neutrons at all energies and prompt neutrons at energies above a threshold. We found that for the candidate detector and for the conditions we considered, a distinctive HEU signature should be detectable, given sufficient detector size, and should be robust over a range of cargo content. In the modeled scenario, an intense neutron source was used to induce fissions in a spherical shell of HEU. To absorb, scatter, and moderate the neutrons, we place one layer of simulated cargo between the source and target and an identical layer between the target and detector. The resulting neutrons and gamma rays are resolved in both time and energy to reveal the portion arising from fission. We predicted the dominant reaction rates within calcium fluoride and liquid organic scintillators. Finally, we assessed the relative effectiveness of two common neutron source energies.
Date: March 9, 2004
Creator: Wolford, J. K.; Frank, M. I. & Descalle, M.
Object Type: Article
System: The UNT Digital Library
Nonproliferation: Improvements Needed for Controls on Exports of Cruise Missile and Unmanned Aerial Vehicle Technology (open access)

Nonproliferation: Improvements Needed for Controls on Exports of Cruise Missile and Unmanned Aerial Vehicle Technology

Testimony issued by the General Accounting Office with an abstract that begins "Cruise missiles and unmanned aerial vehicles (UAV) pose a growing threat to U.S. national security interests as accurate, inexpensive delivery systems for conventional, chemical, and biological weapons. GAO assessed (1) the tools the U.S. and foreign governments use to address proliferation risks posed by the sale of these items and (2) efforts to verify the end use of exported cruise missiles, UAVs, and related technology."
Date: March 9, 2004
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Normalized Texture Motifs and Their Application to Statistical Object Modeling (open access)

Normalized Texture Motifs and Their Application to Statistical Object Modeling

A fundamental challenge in applying texture features to statistical object modeling is recognizing differently oriented spatial patterns. Rows of moored boats in remote sensed images of harbors should be consistently labeled regardless of the orientation of the harbors, or of the boats within the harbors. This is not straightforward to do, however, when using anisotropic texture features to characterize the spatial patterns. We here propose an elegant solution, termed normalized texture motifs, that uses a parametric statistical model to characterize the patterns regardless of their orientation. The models are learned in an unsupervised fashion from arbitrarily orientated training samples. The proposed approach is general enough to be used with a large category of orientation-selective texture features.
Date: March 9, 2004
Creator: Newsam, S D
Object Type: Article
System: The UNT Digital Library
North Texas Daily (Denton, Tex.), Vol. 88, No. 88, Ed. 1 Tuesday, March 9, 2004 (open access)

North Texas Daily (Denton, Tex.), Vol. 88, No. 88, Ed. 1 Tuesday, March 9, 2004

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: March 9, 2004
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Oklahoma Daily (Norman, Okla.), Vol. 87, No. 120, Ed. 1 Tuesday, March 9, 2004 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 87, No. 120, Ed. 1 Tuesday, March 9, 2004

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: March 9, 2004
Creator: King, Christopher R.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Oral History Interview with Eli Escobar, March 9, 2004 transcript

Oral History Interview with Eli Escobar, March 9, 2004

The National Museum of the Pacific War presents an interview with Eli Escobar. Escobar was drafted into the Army in May 1944. When Escobar arrived in France in November, 1944, he joined Company K, 242nd Infantry Regiment, 42nd Infantry Division. In January, 1945, Escobar got captured by German troops near Haguenau. He spent the remainder of the war as a prisoner of war. He was liberated in late April and returned to the US. Escobar was discharged in November, 1945.
Date: March 9, 2004
Creator: Escobar, Eli
Object Type: Sound
System: The Portal to Texas History
Oral History Interview with Eli Escobar, March 9, 2004 (open access)

Oral History Interview with Eli Escobar, March 9, 2004

The National Museum of the Pacific War presents an interview with Eli Escobar. Escobar was drafted into the Army in May 1944. When Escobar arrived in France in November, 1944, he joined Company K, 242nd Infantry Regiment, 42nd Infantry Division. In January, 1945, Escobar got captured by German troops near Haguenau. He spent the remainder of the war as a prisoner of war. He was liberated in late April and returned to the US. Escobar was discharged in November, 1945.
Date: March 9, 2004
Creator: Escobar, Eli
Object Type: Text
System: The Portal to Texas History
Perry Daily Journal (Perry, Okla.), Vol. 111, No. 46, Ed. 1 Tuesday, March 9, 2004 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 111, No. 46, Ed. 1 Tuesday, March 9, 2004

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: March 9, 2004
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
Rains County Leader (Emory, Tex.), Vol. 116, No. 38, Ed. 1 Tuesday, March 9, 2004 (open access)

Rains County Leader (Emory, Tex.), Vol. 116, No. 38, Ed. 1 Tuesday, March 9, 2004

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: March 9, 2004
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Recent results in high pT physics from CDF (open access)

Recent results in high pT physics from CDF

The authors present the most recent high p{sub T} results from the CDF experiment using p{bar p} collisions at {radical}s = 1.96 TeV produced at the Tevatron Collider at Fermilab. They summarize results in electroweak physics, top physics and searches for physics beyond the Standard Model. Many measurements of important signals like W boson, Z boson, and the top quark have been reestablished. Taking advantage of the increase in energy and detector upgrades, these measurements already begin to be competitive with previous results.
Date: March 9, 2004
Creator: Veramendi, G.
Object Type: Article
System: The UNT Digital Library
Restricting Trademark Rights of Cubans: WTO Decision and Congressional Response (open access)

Restricting Trademark Rights of Cubans: WTO Decision and Congressional Response

None
Date: March 9, 2004
Creator: Lee, Margaret Mikyung
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 154, Ed. 1 Tuesday, March 9, 2004 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 89, No. 154, Ed. 1 Tuesday, March 9, 2004

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: March 9, 2004
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Sealy News (Sealy, Tex.), Vol. 117, No. 20, Ed. 1 Tuesday, March 9, 2004 (open access)

The Sealy News (Sealy, Tex.), Vol. 117, No. 20, Ed. 1 Tuesday, March 9, 2004

Semiweekly newspaper from Sealy, Texas that includes local, state, and national news along with advertising.
Date: March 9, 2004
Creator: Griffin, Joanie & Horecka, Bobby
Object Type: Newspaper
System: The Portal to Texas History
Selected Legal and Policy Issues Related to Coalbed Methane Development (open access)

Selected Legal and Policy Issues Related to Coalbed Methane Development

None
Date: March 9, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Summary of the 2003 Moriond Workshop on electroweak interactions and unified theories (open access)

Summary of the 2003 Moriond Workshop on electroweak interactions and unified theories

The 2003 Moriond Workshop on Electroweak Interactions and Unified Theories covered a very rich, diverse array of recent results concerning neutrinos, astrophysics and cosmology, searches for new particles, Higgs physics, precision low-energy measurements, quark flavor physics, CP violation, and electroweak interactions. In this summary, we recapitulate some of the highlights. We update many of the results reported at the Workshop to include newer findings reported during Summer, 2003. In this report, We recount some of the highlights of the 2003 Moriond Workshop on Electroweak Interactions and Unified Theories.
Date: March 9, 2004
Creator: Kayser, Boris
Object Type: Article
System: The UNT Digital Library
A technique for accelerating the convergence of restarted GMRES (open access)

A technique for accelerating the convergence of restarted GMRES

We have observed that the residual vectors at the end of each restart cycle of restarted GMRES often alternate direction in a cyclic fashion, thereby slowing convergence. We present a new technique for accelerating the convergence of restarted GMRES by disrupting this alternating pattern. The new algorithm resembles a full conjugate gradient method with polynomial preconditioning, and its implementation requires minimal changes to the standard restarted GMRES algorithm.
Date: March 9, 2004
Creator: Baker, A H; Jessup, E R & Manteuffel, T
Object Type: Article
System: The UNT Digital Library
Terrorism and Security Issues Facing the Water Infrastructure Sector (open access)

Terrorism and Security Issues Facing the Water Infrastructure Sector

None
Date: March 9, 2004
Creator: unknown
Object Type: Report
System: The UNT Digital Library
An Updated Regional Water Table of the Savannah River Site and Related Coverages (open access)

An Updated Regional Water Table of the Savannah River Site and Related Coverages

A new regional-scale map of the water table configuration beneath the Savannah River Site and its surrounding area has been developed. This map is an update to the regional watertable map presented in1998. While similar methods were used to develop the updated coverages, increased accuracy was achieved due to several factors, including: (a) more data (new wells and additional measurements), (b) use of median versus mean water levels for water table contour development, (c) culling erroneous values from the data records, and (d) eliminating wells discovered to not reflect natural conditions.
Date: March 9, 2004
Creator: Hiergesell, R.A.
Object Type: Report
System: The UNT Digital Library
Void hierarchy and cosmic structure (open access)

Void hierarchy and cosmic structure

Within the context of hierarchical scenarios of gravitational structure formation we describe how an evolving hierarchy of voids evolves on the basis of two processes, the void-in-void process and the void-in-cloud process. The related analytical formulation in terms of a two-barrier excursion problem leads to a self-similarly evolving peaked void size distribution.
Date: March 9, 2004
Creator: Weygaert, Rien van de & Sheth, Ravi
Object Type: Article
System: The UNT Digital Library
www.fermiqcd.net (open access)

www.fermiqcd.net

FermiQCD is a C++ library for fast development of parallel lattice QCD applications. The expression FermiQCD Collaboration is used as a collective name to indicate both the users of the software and its contributors. One of the main differences between FermiQCD and libraries developed by other collaborations is that it follows an object oriented design as opposed to a procedural design. FermiQCD should not be identified exclusively with the implementation of the algorithms but, rather, with the strict specifications that define its Application Program Interface. One should think of FermiQCD as a language on its own (a superset of the C++ language), designed to describe Lattice QCD algorithms. The objects of the language include complex numbers (mdp-complex), matrices (mdp-matrix), lattices (mdp-lattice), fields (gauge-field, fermi-field, staggered-field), propagators (fermi-propagator) and actions. Algorithms written in terms of these objects are automatically parallel.
Date: March 9, 2004
Creator: al., Massino Di Pierro et
Object Type: Article
System: The UNT Digital Library
2002-2003 Engineering Accomplishments: Unconventional Nuclear Weapons Detection (open access)

2002-2003 Engineering Accomplishments: Unconventional Nuclear Weapons Detection

The Defense Threat Reduction Agency, DTRA, is a federal agency charged with safeguarding the nation from weapons of mass destruction, in particular nuclear weapons such as crude devices, and radiological dispersal devices (RDD), also known as dirty bombs. Both of which could be delivered using unconventional means such as by transporting them by a car or boat. Two years ago DTRA partnered with NNSA to evaluate commercially available technologies that could be deployed quickly to defend against threats posed by unconventional nuclear weapons under a program called the Unconventional Nuclear Warfare Defense (UNWD) Program. Lawrence Livermore National Laboratory (LLNL) was one of several National laboratories that participated in this program, which consisted in developing, deploying, and demonstrating detection systems suitable for military base protection. Two key contributions to this program by the LLNL team were the development of two Radiation Detection Buoys (RDB) deployed at Naval Base in Kings Bay in Georgia, and the Detection and Tracking System (DTS) demonstrated at Fort Leonard Wood Missouri, headquarters for the Total Force's Maneuver Support Center (MANSCEN). The RDB's were designed to detect the potential transportation of an unconventional nuclear or radiological weapon by a boat. The RDB's consisted of two commercial marine …
Date: April 9, 2004
Creator: Hernandez, Jose E. & Valentine, John
Object Type: Report
System: The UNT Digital Library
Adaptive Algebraic Multigrid Methods (open access)

Adaptive Algebraic Multigrid Methods

Our ability to simulate physical processes numerically is constrained by our ability to solve the resulting linear systems, prompting substantial research into the development of multiscale iterative methods capable of solving these linear systems with an optimal amount of effort. Overcoming the limitations of geometric multigrid methods to simple geometries and differential equations, algebraic multigrid methods construct the multigrid hierarchy based only on the given matrix. While this allows for efficient black-box solution of the linear systems associated with discretizations of many elliptic differential equations, it also results in a lack of robustness due to assumptions made on the near-null spaces of these matrices. This paper introduces an extension to algebraic multigrid methods that removes the need to make such assumptions by utilizing an adaptive process. The principles which guide the adaptivity are highlighted, as well as their application to algebraic multigrid solution of certain symmetric positive-definite linear systems.
Date: April 9, 2004
Creator: Brezina, M; Falgout, R; MacLachlan, S; Manteuffel, T; McCormick, S & Ruge, J
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 106, No. 8, Ed. 1 Friday, April 9, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 8, Ed. 1 Friday, April 9, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: April 9, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Analytical Solutions for the Nonlinear Longitudinal Drift Compression (Expansion) of Intense Charged Particle Beams (open access)

Analytical Solutions for the Nonlinear Longitudinal Drift Compression (Expansion) of Intense Charged Particle Beams

To achieve high focal spot intensities in heavy ion fusion, the ion beam must be compressed longitudinally by factors of ten to one hundred before it is focused onto the target. The longitudinal compression is achieved by imposing an initial velocity profile tilt on the drifting beam. In this paper, the problem of longitudinal drift compression of intense charged particle beams is solved analytically for the two important cases corresponding to a cold beam, and a pressure-dominated beam, using a one-dimensional warm-fluid model describing the longitudinal beam dynamics.
Date: April 9, 2004
Creator: Startsev, Edward A. & Davidson, Ronald C.
Object Type: Report
System: The UNT Digital Library