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A 2D electrostatic PIC code for the Mark III Hypercube

Description: We have implemented a 2D electrostastic plasma particle in cell (PIC) simulation code on the Caltech/JPL Mark IIIfp Hypercube. The code simulates plasma effects by evolving in time the trajectories of thousands to millions of charged particles subject to their self-consistent fields. Each particle`s position and velocity is advanced in time using a leap frog method for integrating Newton`s equations of motion in electric and magnetic fields. The electric field due to these moving charged partic… more
Date: December 31, 1990
Creator: Ferraro, R. D.; Liewer, P. C. & Decyk, V. K.
Partner: UNT Libraries Government Documents Department
open access

Activated transport in AMTEC electrodes

Description: Transport of alkali metal atoms through porous cathodes of alkali metal thermal-to-electric converter (AMTEC) cells is responsible for significant, reducible losses in the electrical performance of these cells. Experimental evidence for activated transport of metal atoms at grain surfaces and boundaries within some AMTEC electrodes has been derived from temperature dependent studies as well as from analysis of the detailed frequency dependence of ac impedance results for other electrodes, inclu… more
Date: July 1, 1992
Creator: Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.; Underwood, M. L.; O`Connor, D. & Kikkert, S.
Partner: UNT Libraries Government Documents Department
open access

Activated transport in AMTEC electrodes

Description: Transport of alkali metal atoms through porous cathodes of alkali metal thermal-to-electric converter (AMTEC) cells is responsible for significant, reducible losses in the electrical performance of these cells. Experimental evidence for activated transport of metal atoms at grain surfaces and boundaries within some AMTEC electrodes has been derived from temperature dependent studies as well as from analysis of the detailed frequency dependence of ac impedance results for other electrodes, inclu… more
Date: January 1, 1992
Creator: Williams, R.M.; Jeffries-Nakamura, B.; Ryan, M.A.; Underwood, M.L.; O'Connor, D. & Kikkert, S.
Partner: UNT Libraries Government Documents Department
open access

Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

Description: Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of… more
Date: January 1, 1991
Creator: Williams, R.M.; Jeffries-Nakamura, B.; Underwood, M.L.; Ryan, M.A.; O'Connor, D. & Kikkert, S.
Partner: UNT Libraries Government Documents Department
open access

Advances in high temperature components for AMTEC (alkali metal thermal-to-electric converter)

Description: Long lifetimes are required for AMTEC (or sodium heat engine) components for aerospace and terrestrial applications, and the high heat input temperature as well as the alkali metal liquid and vapor environment places unusual demands on the materials used to construct AMTEC devices. In addition, it is important to maximize device efficiency and power density, while maintaining a long life capability. In addition to the electrode, which must provide both efficient electrode kinetics, transport of… more
Date: December 31, 1991
Creator: Williams, R. M.; Jeffries-Nakamura, B.; Underwood, M. L.; Ryan, M. A.; O`Connor, D. & Kikkert, S.
Partner: UNT Libraries Government Documents Department
open access

[Article: Decathlete, family man, games founder]

Description: A magazine article about the last days of Dr. Tom Waddell's life from Dick Schaap's view. Dr. Tom Waddell was the founder of the Gay Games, a famous athlete, and was diagnosed with AIDS.
Date: June 1994
Partner: UNT Libraries Special Collections
open access

The comet Giacobini-Zinner magnetotail: Axial stresses and inferred near-nucleus properties

Description: Utilizing the electron and magnetic field data from the ICE tail traversal of Comet Giacobini-Zinner along with the MHD equations, we have developed a steady state, stress balance model of the cometary magnetotail. With it we infer many important but unmeasured ion properties within the G-Z magnetotail both at ICE and upstream at the average point along each streamline where cometary ions are picked-up. The derived tailward ion flow speed at ICE is quite constant at approx.-20 to -30 km/sec acr… more
Date: October 1, 1986
Creator: McComas, D. J.; Gosling, J. T.; Bame, S. J.; Slavin, J. A.; Smith, E. J. & Steinberg, J. L.
Partner: UNT Libraries Government Documents Department
open access

A Critique of Kellehear's Transcendent Society

Description: Article responding to Allen Kellehear's cultural analysis based on nine Mormon near-death experiences (NDEs) did not reflect the diversity of near-death visions from other cultures. It suggests that these Mormon NDEs were neither as utopian as Kellehear assumed nor representative of contemporary NDE reports, and that a more complete analysis would reveal a variety of NDEs and otherworld visions reflecting the experiencers' sociocultural background.
Date: Winter 1991
Creator: Mickel, Howard A.
Partner: UNT Libraries
open access

[The Dallas Morning News, 'Museum director resigns']

Description: An article written by Janet Kutner for The Dallas Morning News that announces the resignation of E. A. Carmean Jr. as director of the Modern Art Museum of Fort Worth. The piece covers the work he did while at the museum.
Date: 199X
Creator: Kutner, Janet
Partner: UNT Libraries Special Collections
open access

The Death Journey of a Hopi Indian: A Case Study

Description: Article presenting the case study of the "death journey" or near-death experience (NDE) of Don Talayesva, a Hopi Indian, whose experience occurred between 1900 and 1910. The article compares and contrasts his experience with 11 accounts of Native American NDEs reported by Jenny Wade, as well as with modern day NDEs.
Date: Summer 2008
Creator: Green, J. Timothy
Partner: UNT Libraries
open access

[Denton Record-Chronicle articles, June 10, 1990]

Description: A clipping of an article by Susan Shelton for the Denton Record-Chronicle about the new NTIEVA program's reworking of art education in Metroplex schools. Another piece by Shelton that is included covers Dr. Warren Carver's support of the program.
Date: June 10, 1990
Creator: Shelton, Susan
Partner: UNT Libraries Special Collections
open access

Describing the Light: Attribution Theory as an Explanation of the Near-Death Experience

Description: Article exploring near-death experiences and attribution theory, which focuses on how information is used to create causal inferences and answer causal questions. The finding that near-death experiencers (NDErs) rarely describe unknown events, characters, or objects suggests that NDErs make attributions to answer why these experiences occurred. Examining various descriptions of NDEs demonstrates how attribution theory explains individuals' descriptions of their NDEs.
Date: Spring 1995
Creator: Norton, Max C. & Sahlman, James M.
Partner: UNT Libraries
open access

Design considerations for a fiber optic communications network for power systems

Description: The design of a fiber optic communication network for monitoring and control in power systems is discussed. It is shown that by appropriate choice of protocols, a fault-tolerant system can be built that operates in any arbitrary configuration. Since the network is based on fiber optics, it can be made fast enough for substation monitoring and control. In this application, a relatively small number of cables is required to implement a high reliability system. The network can also be used for dis… more
Date: August 1, 1993
Creator: Kirkham, H.; Johnston, A. R. & Allen, G. D.
Partner: UNT Libraries Government Documents Department
open access

Dual arm master controller concept

Description: The Advanced Servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm m… more
Date: January 1, 1984
Creator: Kuban, D.P. & Perkins, G.S.
Partner: UNT Libraries Government Documents Department
open access

Dual arm master controller development

Description: The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance, gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape-driven manipulators. Studies were performed which addressed the human factors design and performance trade-offs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm m… more
Date: January 1, 1985
Creator: Kuban, D. P. & Perkins, G. S.
Partner: UNT Libraries Government Documents Department
open access

Dynamic load balancing in a concurrent plasma PIC code on the JPL/Caltech Mark III hypercube

Description: Dynamic load balancing has been implemented in a concurrent one-dimensional electromagnetic plasma particle-in-cell (PIC) simulation code using a method which adds very little overhead to the parallel code. In PIC codes, the orbits of many interacting plasma electrons and ions are followed as an initial value problem as the particles move in electromagnetic fields calculated self-consistently from the particle motions. The code was implemented using the GCPIC algorithm in which the particles ar… more
Date: December 31, 1990
Creator: Liewer, P. C.; Leaver, E. W.; Decyk, V. K. & Dawson, J. M.
Partner: UNT Libraries Government Documents Department
open access

Efficiency of an AMTEC recirculating test cell, experiments and projections

Description: The alkali metal thermal to electric converter (AMTEC) is an electrochemical device for the direct conversion of heat to electrical energy with efficiencies potentially near Carnot. The future usefulness of AMTEC for space power conversion depends on the efficiency of the devices. Systems studies have projected from 15% to 35% thermal to electric conversion efficiencies, and one experiment has demonstrated 19% efficiency for a short period of time. Recent experiments in a recirculating test cel… more
Date: May 1, 1992
Creator: Underwood, M. L.; O`Connor, D.; Williams, R. M.; Jeffries-Nakamura, B. & Ryan, M. A.
Partner: UNT Libraries Government Documents Department
open access

Experimental evaluation of a fixed collector employing vee-trough concentrator and vacuum tube receivers

Description: A test bed for experimental evaluation of a fixed solar collector which combines an evacuated glass tube solar receiver with a flat plate/black chrome plated copper absorber and an asymmetric veetrough concentrator was designed and constructed. Earlier predictions of thermal performance were compared with test data acquired for a bare vacuum tube receiver; and receiver tubes with Alzak aluminum, aluminized FEP Teflon film laminated sheet metal and second surface ordinary mirror reflectors. Test… more
Date: January 1, 1977
Creator: Selcuk, M. K.
Partner: UNT Libraries Government Documents Department
open access

External flow radiators for reduced space powerplant temperatures. Technical information report

Description: Nuclear space powerplants can operate at temperatures below 900 K and use stainless steel construction without a weight penalty if new radiator concepts can achieve radiator weights of 1-3 kg/m{sup 2}. Conventional tube-and-fin radiators weight about 10 kg/m{sup 2} because of heavy tube walls to prevent meteroid puncture. Radiator designs that do not require meteroid protection are possible; they operate with fluids of low vapor pressure that can be exposed directly to space in external-flow ra… more
Date: January 1, 1984
Creator: Elliott, D. G.
Partner: UNT Libraries Government Documents Department
open access

Generation of a strong core-centering force in a submillimeter compound droplet system

Description: By amplitude-modulating the driving voltage of an acoustic levitating apparatus, a strong core-centering force can be generated in a submillimeter compound droplet system suspended by the radiation pressure in a gaseous medium. Depending on the acoustic characteristics of the droplet system, it has been found that the technique can be utilized advantageously in the multiple-layer coating of an inertial-confinement-fusion pellet.
Date: January 1, 1981
Creator: Lee, M. C.; Feng, I.; Elleman, D. D.; Wang, T. G. & Young, A. T.
Partner: UNT Libraries Government Documents Department
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