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Infiltration Heat Recovery in Building Walls: Computational Fluid Dynamics Investigations Results (open access)

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

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 study, Computational Fluid Dynamics was used to calculate infiltration heat recovery under a range of idealized conditions, specifically to understand factors that influence it, and assess its significance in building heat load calculations. This study shows for the first time the important effect of the external boundary layers on conduction and infiltration heat loads. Results show (under the idealized conditions studied here) that (1) the interior details of the wall encountered in the leakage pa th (i.e., insulated or empty walls) do not greatly influence the IHR, the overall relative location of the cracks (i.e., inlet and outlet locations on the wall) has the largest influence on the IHR magnitude, (2) external boundary layers on the walls substantially contribute to IHR and (3) the relative error in heat load calculations …
Date: August 5, 2002
Creator: Abadie, Marc O.; Finlayson, Elizabeth U. & Gadgil, Ashok J.
Object Type: Report
System: The UNT Digital Library
A Metadata Approach to Preservation of Digital Resources: The University of North Texas Libraries' Experience (open access)

A Metadata Approach to Preservation of Digital Resources: The University of North Texas Libraries' Experience

Article discussing metadata approaches to preservation of digital resources and the experiences of the University of North Texas (UNT) Libraries.
Date: August 5, 2002
Creator: Alemneh, Daniel Gelaw; Hastings, Samantha Kelly & Hartman, Cathy Nelson
Object Type: Article
System: The UNT Digital Library
Bosnia: U.S. Military Operations (open access)

Bosnia: U.S. Military Operations

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.
Object Type: Report
System: The UNT Digital Library
Chemical Weapons Convention: Issues for Congress (open access)

Chemical Weapons Convention: Issues for Congress

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 coverage to not only governmental but also civilian facilities. The Convention also requires export controls and reporting requirements on chemicals that can be used as warfare agents and their precursors. The CWC establishes the Organization for the Prohibition of Chemical Weapons (OPCW) to oversee the Convention’s implementation.
Date: August 5, 2002
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
Kosovo and Macedonia: U.S. and Allied Military Operations (open access)

Kosovo and Macedonia: U.S. and Allied Military Operations

None
Date: August 5, 2002
Creator: Bowman, Steven R.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 278, Ed. 1 Monday, August 5, 2002 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 278, Ed. 1 Monday, August 5, 2002

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Daily Journal (Perry, Okla.), Vol. 109, No. 153, Ed. 1 Monday, August 5, 2002 (open access)

Daily Journal (Perry, Okla.), Vol. 109, No. 153, Ed. 1 Monday, August 5, 2002

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, August 5, 2002 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, August 5, 2002

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 104, No. 121, Ed. 1 Monday, August 5, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 121, Ed. 1 Monday, August 5, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 252, Ed. 1 Monday, August 5, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 252, Ed. 1 Monday, August 5, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 5, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Oral History Interview with Joe Drastata, August 5, 2002 transcript

Oral History Interview with Joe Drastata, August 5, 2002

The National Museum of the Pacific War presents an oral interview with Joe Drastata. Drastata was born in El Campo, Texas on 1 August 1924 and entered the Army Air Forces in March 1943. After receiving initial training at Jefferson Barracks, Missouri he was sent to Fort Bragg, North Carolina where he was assigned to the 65th Troop Carrier Squadron, 403rd Troop Carrier Group. During July 1943 the unit went on board the USAT Maui bound for Australia. Drastata tells of the 28 day trip and describes the King Neptune ceremony when crossing the Equator. He describes the uncomfortable sleeping accommodations coupled with extensive rain and swarms of mosquitoes encountered at Port Moresby, New Guinea. He was assigned to communications assisting in duties that involved flag or light signals, land lines, switchboards and public address systems. The unit moved to various locations including Biak where he recounts an accident that claimed the life of a young officer. On 3 February 1945, the 65th Troop Carrier Squadron dropped paratroopers on the Los Banos prison camp to free the allied captives. Although Drastata was not personally involved in the operation he discusses various facets of this successful operation. He returned to the …
Date: August 5, 2002
Creator: Drastata, Joe
Object Type: Sound
System: The Portal to Texas History
Oral History Interview with Joe Drastata, August 5, 2002 (open access)

Oral History Interview with Joe Drastata, August 5, 2002

The National Museum of the Pacific War presents an oral interview with Joe Drastata. Drastata was born in El Campo, Texas on 1 August 1924 and entered the Army Air Forces in March 1943. After receiving initial training at Jefferson Barracks, Missouri he was sent to Fort Bragg, North Carolina where he was assigned to the 65th Troop Carrier Squadron, 403rd Troop Carrier Group. During July 1943 the unit went on board the USAT Maui bound for Australia. Drastata tells of the 28 day trip and describes the King Neptune ceremony when crossing the Equator. He describes the uncomfortable sleeping accommodations coupled with extensive rain and swarms of mosquitoes encountered at Port Moresby, New Guinea. He was assigned to communications assisting in duties that involved flag or light signals, land lines, switchboards and public address systems. The unit moved to various locations including Biak where he recounts an accident that claimed the life of a young officer. On 3 February 1945, the 65th Troop Carrier Squadron dropped paratroopers on the Los Banos prison camp to free the allied captives. Although Drastata was not personally involved in the operation he discusses various facets of this successful operation. He returned to the …
Date: August 5, 2002
Creator: Drastata, Joe
Object Type: Text
System: The Portal to Texas History
Project Plan for Vertical Lift Machine (open access)

Project Plan for Vertical Lift Machine

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 predetermined heights, in relation to other objects suspended from above, for high neutron multiplication experiments. Operation of the machine during the experiments is done remotely. The lift mechanism shall accommodate various platforms (tables) that support the objects to be raised. A frame will support additional subassemblies from above such that the lower subassembly can be raised close to and/or interface with those above. The structure must be stiff and motion of the table linear such that radial alignment is maintained (e.g. concentricity). The safe position for the Vertical Lift Machine is the lift mechanism fully retracted with the subassemblies fully separated. The machine shall reside in this position when not in use. It must return to this safe condition from any position …
Date: August 5, 2002
Creator: Ellsworth, G F
Object Type: Report
System: The UNT Digital Library
Chamber wall response to target implosion in inertial fusion reactors : new and critical assessments. (open access)

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

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 methods include use of solid bare walls, gas-filled cavities, and liquid walls/jets. Detailed models have been developed for reflected laser light, emitted photons, and target debris deposition and interaction with chamber components and have been implemented in the comprehensive HEIGHTS software package. The hydrodynamic response of gas filled cavities and photon radiation transport of the deposited energy has been calculated by means of new and advanced numerical techniques. Fragmentation models of liquid jets as a result of the deposited energy have also been developed, and the impact on chamber clearing dynamics has been evaluated. The focus of this study is to critically assess the reliability and the dynamic response of chamber walls in various proposed protection methods for IFE systems. Of particular concern is the effect on …
Date: August 5, 2002
Creator: Hassanein, A. & Morozov, V.
Object Type: Article
System: The UNT Digital Library
A SPICE Model and Electrostatic Field Analysis of the MOS Turn-Off Thyristor (open access)

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

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 create a four-terminal sub-circuit component representing the MTO that can be readily imported into computer-aided circuit design programs such as PSPICE and Micro-Cap. The generated static I-V characteristics and simulated switching waveforms are shown. The electrostatic field analysis was done for the maximum operating voltage of 4.5 kV using the Ansoft Maxwell 3D field simulator. Electrostatic field magnitudes that exceed the nominal air breakdown threshold of 30 kV/cm were observed surrounding the simulated turn-off gate wire, the turn-off gate ring contact, and the cathode ring contact. The resulting areas of high fields are a concern, as arc track marks have been found on the inner surface of the ceramic insulator near the internal gate connections of a failed device.
Date: August 5, 2002
Creator: Kelly, D. Q.; Mayhall, D. J.; Wilson, M. J. & Lahowe, D. A.
Object Type: Report
System: The UNT Digital Library
Modeling the Evolution of Strength During Wire Drawing (open access)

Modeling the Evolution of Strength During Wire Drawing

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 function of pearlite colony size, interlamellar spacing and the size of the stable dislocation cells that are produced during wire drawing. The results have been used to model the evolution of strength during wire drawing. Model predictions for the evolution of tensile strength with drawing strain show excellent agreement with data derived from a number of eutectoid and hyperectectoid steels as a function of drawing strain.
Date: August 5, 2002
Creator: Lesuer, D R; Syn, C K & Sherby, O D
Object Type: Article
System: The UNT Digital Library
Beatrice Alba Martinez to represent Dallas on DART Board of Directors (open access)

Beatrice Alba Martinez to represent Dallas on DART Board of Directors

News release about the appointment of Beatrice Martinez to the DART Board of Directors, representing the city of Dallas.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
DART's Cowboys Flyer Makes 'road trips' easier for fans (open access)

DART's Cowboys Flyer Makes 'road trips' easier for fans

News release about DART's "Cowboy Flyer" shuttle service to Dallas Cowboy games.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Joyce Foreman to represent Dallas on DART Board of Directors (open access)

Joyce Foreman to represent Dallas on DART Board of Directors

News release about the appointment of Joyce Foreman to the DART Board of Directors, representing the city of Dallas.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Proposed bus service changes presented in community meetings (open access)

Proposed bus service changes presented in community meetings

News release concerning DART public meetings to gather input on proposed bus service changes in coordination with the agency's light rail expansion.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
Randall D. Chrisman to represent Carrollton and Irving on DART Board of Directors (open access)

Randall D. Chrisman to represent Carrollton and Irving on DART Board of Directors

News release about the appointment of Randall D. Chrisman to DART Board of Directors, representing the cities of Carrollton and Irving.
Date: August 5, 2002
Creator: Lyons, Morgan
Object Type: Text
System: The Portal to Texas History
National Spherical Torus Experiment Real Time Plasma Control Data Acquisition Hardware (open access)

National Spherical Torus Experiment Real Time Plasma Control Data Acquisition Hardware

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 Panel Data Port (FPDP) for high-speed data transfer. Data coming from physically different locations is referenced to several different ground potentials necessitating the need for a custom FPDP multiplexer. This paper discusses the data acquisition system configuration, the in-house designed 4-to-1 FPDP Input Multiplexing Module (FIMM), and future expansion plans.
Date: August 5, 2002
Creator: Marsala, R. J. & Schneider, J.
Object Type: Report
System: The UNT Digital Library
Monitoring Carbon Dioxide Sequestration Using Electrical Resistance Tomography (ERT): A Minimally Invasive Method (open access)

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

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 fluids. High resolution tomographs of electrical properties are now used for site characterization and to monitor subsurface migration of fluids (i.e., leaking underground tanks, infiltration events, steam floods, contaminant movement, and to assess the integrity of engineered barriers). When electrical resistance tomography (ERT) imaging can be performed using existing well casings as long electrodes, the method is nearly transparent to reservoir operators, and reduces the need for additional drilling. Using numerical simulations and laboratory experiments, we have conducted sensitivity studies to determine the potential of ERT methods to detect and monitor the migration of CO{sub 2} in the subsurface. These studies have in turn been applied to the design and implementation of the first field casing surveys conducted in an oil field undergoing a CO{sub 2} flood.
Date: August 5, 2002
Creator: Newmark, R. L.; Ramirez, A. L. & Daily, W. D.
Object Type: Article
System: The UNT Digital Library
Advanced Techniques for Fourier Transform Wavefront Reconstruction (open access)

Advanced Techniques for Fourier Transform Wavefront Reconstruction

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 can be implemented at the filtering stage, preserving the speed of FT reconstruction. Simulation of a large system shows how compensated FT methods can have equivalent or better performance to slower vector-matrix-multiply reconstructions.
Date: August 5, 2002
Creator: Poyneer, L A
Object Type: Article
System: The UNT Digital Library