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open access

Practical path planning among movable obstacles

Description: Path planning among movable obstacles is a practical problem that is in need of a solution. In this paper an efficient heuristic algorithm that uses a generate-and-test paradigm: a good'' candidate path is hypothesized by a global planner and subsequently verified by a local planner. In the process of formalizing the problem, we also present a technique for modeling object interactions through contact. Our algorithm has been tested on a variety of examples, and was able to generate solutions wi… more
Date: September 5, 1990
Creator: Chen, Pang C. & Hwang, Yong K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Theoretical/numerical investigation of induction cavity impedances for moderate to large gap widths

Description: In order to understand the coupling of a charged particle beam to modes in induction cells with gap width -- to -- beampipe radius ratio w/b > 1, the variation of the transverse Z/Q for both axially symmetric and axially asymmetric dipole modes in this regime is investigated. It is found that the gross behavior of the axially symmetric modes when w/b > 1 is at least consistent with the approximate analysis of Briggs, although a thorough comparison has not been undertaken. The axially asymmetric… more
Date: September 5, 1990
Creator: DeFord, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Relativistic klystrons for high-gradient accelerators

Description: Experimental work is being performed by collaborators at LLNL, SLAC, and LBL to investigate relativistic klystrons as a possible rf power source for future high-gradient accelerators. We have learned how to overcome or previously reported problem of high power rf pulse shortening and have achieved peak rf power levels of 330 MW using an 11.4-GHz high-gain tube with multiple output structures. In these experiments the rf pulse is of the same duration as the beam current pulse. In addition, exper… more
Date: September 5, 1990
Creator: Westenskow, G. A.; Aalberts, D. P.; Boyd, J. K.; Deis, G. A.; Houck, T. L.; Orzechowski, T. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
captions transcript

[News Clip: Kuwait Fuel]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: September 5, 1990, 6:00 p.m.
Duration: 1 minute 40 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Drug War]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: September 5, 1990, 10:00 p.m.
Duration: 1 minute 53 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Yellow Ribbon]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: September 5, 1990, 5:00 p.m.
Duration: 43 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Defense - Quayle]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: September 5, 1990, 6:00 p.m.
Duration: 1 minute 41 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Kid Porn]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 6pm.
Date: September 5, 1990, 6:00 p.m.
Duration: 1 minute 48 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
open access

Dispersion and interbunch energy variation for an E sup + E sup minus linear collider

Description: Recent studies concerning optimization parameters for e{sup +}e{sup {minus}} super linear colliders use multiple particle bunches for each rf pulse to increase the luminosity and overall efficiency. Requirements for final focusing of the beams severely restrict the bunch to bunch energy variation during the rf pulse. To accurately determine the accelerating fields and energy variation, the dispersion related transient behavior of the rf drive pulse must be considered. A numerical study of dispe… more
Date: September 5, 1990
Creator: Houck, T.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Application of Linear Magnetic Loss Model of Ferrite to Induction Cavity Simulation

Description: A linear, frequency independent model of the rf properties of unbiased, soft ferrite has been implemented in finite-difference, time-domain, electromagnetic simulation code AMOS for the purposes of studying linac induction cavities. The simple model consists of adding a magnetic conductivity term ({sigma}{sub m}H) to Faraday's Law. The value of {sigma}{sub m} that is appropriate for a given ferrite at a particular frequency is obtained via an rf reflection experiment on a very thin ferrite toro… more
Date: September 5, 1990
Creator: DeFord, J. F. & Kamin, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

A chemical kinetic modeling study of chlorinated hydrocarbon combustion

Description: The combustion of chloroethane is modeled as a stirred reactor so that we can study critical emission characteristics of the reactor as a function of residence time. We examine important operating conditions such as pressure, temperature, and equivalence ratio and their influence on destructive efficiency of chloroethane. The model uses a detailed chemical kinetic mechanism that we have developed previously for C{sub 3} hydrocarbons. We have added to this mechanism the chemical kinetic mechanis… more
Date: September 5, 1990
Creator: Pitz, W.J. & Westbrook, C.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Avalanche transistor selection for long term stability in streak camera sweep and pulser applications

Description: We have identified the Motorola 2N4014 and 2N5551 and the Raytheon RS3944 as three transistor types that exhibit avalanche characteristics and have long term collector breakdown voltage stability superior to other transistors tested. Stability on all types has been improved by power burnin. An automatic avalanche transistor burnin tester has been constructed to allow power burnin of up to 1008 transistors at a time. The tester is controlled by an IBM Personal Computer (PC) and can be programmed… more
Date: September 5, 1990
Creator: Thomas, S.W.; Griffith, R.L. & Teruya, A.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
captions transcript

[News Clip: Quayle]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 12 P.M.
Date: September 5, 1990
Duration: 1 minute 41 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Gun control]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 6 P.M.
Date: September 5, 1990
Duration: 1 minute 55 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Drug war]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 10 P.M.
Date: September 5, 1990
Duration: 1 minute 52 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Kuwait fuel]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 6 P.M.
Date: September 5, 1990
Duration: 1 minute 40 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Otwell]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story. This story aired at 10 P.M.
Date: September 5, 1990
Duration: 1 minute 13 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
open access

Response of Tundra Ecosystems to Elevated Atmospheric CO{sub 2}

Description: OAK B188 Response of Tundra Ecosystems to Elevated Atmospheric CO{sub 2}. Atmospheric CO{sub 2} is expected to double by the end of the next century. Global mean increases in surface air temperature of 1.5-4.5 C are anticipated with larger increases towards the poles predicted. Changes in CO{sub 2} levels and temperature could have major impacts on ecosystem functioning, including primary productivity, species composition, plant-animal interactions, and carbon storage. Until recently, there has… more
Date: September 5, 1990
Creator: Oechel, Walter C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
captions transcript

[Lewisville Elementary School]

Description: A video of school children at a Lewisville elementary school.
Date: September 5, 1990
Duration: 31 minutes 09 seconds
Creator: University of North Texas. Center for Media Production.
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
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