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Port Security: Nation Faces Formidable Challenges in Making New Initiatives Successful

Description: Testimony issued by the General Accounting Office with an abstract that begins "Although most of the attention following the September 11 terrorist attacks focused on airport security, an increasing emphasis has since been placed on ports. Ports are inherently vulnerable to terrorist attacks because of their size, generally open accessibility by water and land, metropolitan area location, the amount of material being transported through ports, and the ready transportation links to many location… more
Date: August 5, 2002
Creator: United States. General Accounting Office.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

A SPICE Model and Electrostatic Field Analysis of the MOS Turn-Off Thyristor

Description: This paper presents a circuit model and an electrostatic field analysis with an approximate model of the SDM170HK MOS turn-off thyristor (MTO) fabricated by Silicon Power Corporation. The circuit model consists of five cells, each containing two bipolar junction transistors and three resistors. The turn-off feature of the MTO was simulated by inserting an array of 21 Fairchild FDS6670A MOSFET importable sub-circuit components between the cathode and the turn-on gate. The model was then used to … more
Date: August 5, 2002
Creator: Kelly, D. Q.; Mayhall, D. J.; Wilson, M. J. & Lahowe, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chamber wall response to target implosion in inertial fusion reactors : new and critical assessments.

Description: The chamber walls in inertial fusion energy (IFE) reactors are exposed to harsh conditions following each target implosion. Key issues of the cyclic IFE operation include intense photon and ion deposition, wall thermal and hydrodynamic evolution, wall erosion and fatigue lifetime, and chamber clearing and evacuation to ensure desirable conditions prior to target implosion. Several methods for wall protection have been proposed in the past, each having its own advantages and disadvantages. These… more
Date: August 5, 2002
Creator: Hassanein, A. & Morozov, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Evaluation of Possible Nuclear Magnetic Resonance Diagnostic Techniques for Tokamak Experiments

Description: Potential applications of nuclear magnetic resonance (NMR) diagnostic techniques to tokamak experiments are evaluated. NMR frequencies for hydrogen isotopes and low-Z nuclei in such experiments are in the frequency range approximately equal to 20-200 MHz, so existing RF [radio-frequency] antennas could be used to rotate the spin polarization and to make the NMR measurements. Our tentative conclusion is that such measurements are possible if highly spin polarized H or (superscript)3He gas source… more
Date: August 5, 2002
Creator: Zweben, S. J.; Kornack, T. W.; Majeski, D.; Schilling, G.; Skinner, C. H. & Wilson, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

National Spherical Torus Experiment Real Time Plasma Control Data Acquisition Hardware

Description: The National Spherical Torus Experiment (NSTX) is currently providing researchers data on low aspect-ratio toroidal plasmas. NSTX's Plasma Control System adjusts the firing angles of thyristor rectifier power supplies, in real time, to control plasma position, shape and density. A Data Acquisition system comprised of off-the-shelf and custom hardware provides the magnetic diagnostics data required in calculating firing angles. This VERSAmodule Eurocard (VME) bus-based system utilizes Front Pane… more
Date: August 5, 2002
Creator: Marsala, R. J. & Schneider, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Modeling the Evolution of Strength During Wire Drawing

Description: Extensive plastic deformation during wire drawing is commonly used to produce steel wires with very high strengths. Typically these steels are eutectoid and hypereutectoid steels and drawing strains up to 4 are used during processing. The resulting materials can have tensile strengths in excess of 4000 MPa. The evolution of microstructure and the strengthening mechanisms resulting from wire drawing have been studied for eutectoid and hypereutectoid steels. Strength has been shown to be a functi… more
Date: August 5, 2002
Creator: Lesuer, D R; Syn, C K & Sherby, O D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Project Plan for Vertical Lift Machine

Description: This document describes the Project Plan for the development and manufacture of a Vertical Lift Machine. It is assumed by this project plan that the Vertical Lift Machine will be developed, designed, manufactured, and tested by a qualified vendor. LLNL will retain review and approval authority for each step given in this project plan. The Vertical Lift Machine is a single linear axis positioning device capable of lifting objects vertically at controlled rates and positioning them repeatedly at … more
Date: August 5, 2002
Creator: Ellsworth, G F
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Advanced Techniques for Fourier Transform Wavefront Reconstruction

Description: The performance of Fourier transform (FT) reconstructors in large adaptive optics systems with Shack-Hartmann sensors and a deformable mirror is analyzed. FT methods, which are derived for point-based geometries, are adapted for use on the continuous systems. Analysis and simulation show how to compensate for effects such as misalignment of the deformable mirror and wavefront sensor gain. Further filtering methods to reduce noise and improve performance are presented. All these modifications ca… more
Date: August 5, 2002
Creator: Poyneer, L A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Infiltration Heat Recovery in Building Walls: Computational Fluid Dynamics Investigations Results

Description: Conventional calculations of heating (and cooling) loads for buildings assume that conduction heat loss (or gain) through walls is independent of air infiltration heat loss (or gain). During passage through the building envelope, infiltrating air substantially exchanges heat wall insulation leading to partial recovery of heat conducted through the wall. The Infiltration Heat Recovery (IHR) factor was introduced to quantify the heat recovery and correct the conventional calculations. In this stu… more
Date: August 5, 2002
Creator: Abadie, Marc O.; Finlayson, Elizabeth U. & Gadgil, Ashok J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CHEMICALLY BONDED CEMENTS FROM BOILER ASH AND SLUDGE WASTES. PHASE I REPORT AUGUST 1997 - JULY 1998

Description: In exploring methods to recycle boiler ash (BA) and waste water treatment sludge (WWTS), by-products generated from Keyspan's power plants, into commercially viable materials, we synthesized chemically bonded cements (CBC) offering the following three specific characteristics; (1) immobilization of hazardous heavy metals, such as Pb, Ni, and V, (2) rapid hardening and setting properties, and (3) development of high mechanical strength. The CBCs were prepared through an acid-base reaction betwee… more
Date: August 5, 2002
Creator: SUGAMA,T. & YAGER,K.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Tomography (ERT): A Minimally Invasive Method

Description: Successful geologic sequestration of carbon dioxide (CO{sub 2}), will require monitoring the CO{sub 2} injection to confirm the performance of the caprock/reservoir system, assess leaks and flow paths, and understand the geophysical and geochemical interactions between the CO{sub 2} and the geologic minerals and fluids. Electrical methods are especially well suited for monitoring processes involving fluids, as electrical properties are sensitive to the presence and nature of the formation fluid… more
Date: August 5, 2002
Creator: Newmark, R. L.; Ramirez, A. L. & Daily, W. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Bosnia: U.S. Military Operations

Description: This report outlines U.S. military operations in Bosnia and discusses issues such as U.S. and Allied Participation in Bosnia Peacekeeping (IFOR/SFOR), duration, cost, arms control and military assistance. This report also includes most recent development, background analysis, and legislation.
Date: August 5, 2002
Creator: Bowman, Steven R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Chemical Weapons Convention: Issues for Congress

Description: The CWC bans the development, production, stockpiling, and use of chemical weapons by members signatories. It also requires the destruction of all chemical weapons stockpiles and production facilities. Neither the United States nor Russia will be able to meet the original CWC’s deadlines for destruction of their CW stockpiles, and have been granted extensions to at least 2012. The Convention provides the most extensive and intrusive verification regime of any arms control treaty, extending its … more
Date: August 5, 2002
Creator: Bowman, Steven R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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