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Implementation of logical networks in System 2000 data bases

Description: The need for a means to express general relationships (networks) among entity occurrences (data sets) in System 2000 data bases is established. Integer expression of general path segments is described as a means to meet this need. Operations on the expressions are also described. Two possible implementations are discussed. Either or both of these implementations can be included by the user in System 2000 data bases. They are compatible with the System 2000 hierarchical data model, and could als… more
Date: May 1, 1980
Creator: Hall, R. C.
Partner: UNT Libraries Government Documents Department
open access

Measurement of radiofrequency fields

Description: We are literally surrounded by radiofrequency (RFR) and microwave radiation, from both natural and man-made sources. The identification and control of man-made sources of RFR has become a high priority of radiation safety professionals in recent years. For the purposes of this paper, we will consider RFR to cover the frequencies from 3 kHz to 300 MHz, and microwaves from 300 MHz to 300 GHz, and will use the term RFR interchangeably to describe both. Electromagnetic radiation and field below 3 k… more
Date: May 1, 1992
Creator: Leonowich, J.A.
Partner: UNT Libraries Government Documents Department
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Broadband diffractive lens

Description: Significant progress has been made toward solving the century-old problem of chromatic aberrations in diffractive optics. Our approach exploits modern materials and microfabrication technology and is very different from the purely diffractive strategy,'' which is commonly employed and which results in multiple diffractive elements separated by a finite distance. We have developed a Fresnel zone plate lens comprised of a serial stack of patterned minus-filters which allows broadband radiation to… more
Date: May 28, 1991
Creator: Ceglio, N. M.; Hawryluk, A. M.; London, R. A.; Seppala, L. G. (Lawrence Livermore National Lab., CA (USA)) & Gaines, D. P. (Brigham Young Univ., Provo, UT (USA))
Partner: UNT Libraries Government Documents Department
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BRUTE

Description: BRUTE is an algorithm to derive the implied boundary of a piecepart from the part's wireframe representation. BRUTE's input is an IGES file. The geometry is extracted and used to derive the edge-vertex (EV) topology. BRUTE then uses a divide-and-conquer method to derive all reasonable face-edge-vertex (FEV) topologies from the EV topology. The final step is to determine the geometry of each face by using the geometry of its edges. Any FEV topology that contains a face that is not a valid surfac… more
Date: May 1, 1982
Creator: Christensen, N.C.
Partner: UNT Libraries Government Documents Department
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Two-Photon Collisions and QCD

Description: A critical review of the applications of QCD to low- and high-p/sub T/ interactions of two photons is presented. The advantages of the two-photon high-p/sub T/ tests over corresponding hadronic beam and/or target tests of QCD are given particular emphasis.
Date: May 1, 1980
Creator: Gunion, J. F.
Partner: UNT Libraries Government Documents Department
open access

Optimal forced-air distribution in new housing

Description: This paper summarizes a system integration approach to residential heating, cooling, and ventilation, embodied in a tight building envelope with precooling and dehumidification of forced ventilation air, and with ducts in the conditioned space.
Date: May 1, 1992
Creator: Andrews, J. W.
Partner: UNT Libraries Government Documents Department
open access

Fabrication development of full-sized components for GCFR core assemblies

Description: This paper presents the status of the development of full-sized components for gas-cooled fast reactor (GCFR) core assemblies. Methods for ribbing of the fuel rod cladding, fabrication of grid spacers of two different designs, drawing of assembly flow ducts, and fabrication of fission gas collection manifolds by several methods are discussed.
Date: May 1980
Creator: Lindgren, J. R.; Flynn, P. W. & Foster, L. C.
Partner: UNT Libraries Government Documents Department
open access

Writing audit findings: Be reasonable

Description: A customary approach to auditing and reporting deficiencies is to keep a running list of those that are found, evaluate the severity of each, and based on the evidence, document findings or observations or concerns in an audit report. The report is issued and the auditee is normally requested to address root cause'' as part of their corrective action. This paper describes a root problems'' approach to documenting audit findings that is designed not only to put the QA auditor in a more favorable… more
Date: May 1, 1992
Creator: Girvin, N.W.
Partner: UNT Libraries Government Documents Department
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Electron ray tracing programs for gun design and beam transport. [None]

Description: Computer simulation of electron and ion sources is made by using a class of computer codes known as gun design programs. In this paper, we shall first list most of the necessary and some optional capabilities of such programs. Then we will briefly note specific codes and/or authors of codes with attention to specialized applications if any. There may be many more such programs in use than are treated here; we are only trying to cover a range of examples, not perform a comprehensive survey.
Date: May 1, 1988
Creator: Herrmannsfeldt, W.B.
Partner: UNT Libraries Government Documents Department
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New rf power system for SuperHILAC

Description: The upgraded rf system for the SuperHILAC is now operational using 9 new tetrode amplifiers. Each amplifier can produce in excess of 1MW of 70 Mhz pulsed rf power. Ferrite is used to decouple the screen grid circuit and to absorb parasitic oscillations. This results in a very stable amplifier with reasonable gain. This system uses a common 8 MW anode power supply and crowbar system. Overall system efficiency has been increased significantly. We project a 3 year payback on the equipment cost, re… more
Date: May 1, 1985
Creator: Fugitt, J.; Lancaster, H. & Sorensen, R.
Partner: UNT Libraries Government Documents Department
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High-temperature borate liquids: physical properties of glass-forming compositions

Description: Several experimental routes can be used to develop a better understanding of the polymeric constitution (polyanionic and/or polyhedral distribution) of borate, germanate, and silicate glasses. Spectral, chemical, physical-chemical, and mechanical property information can be determined directly for the glass compositions of interest. Generally, only physical-chemical information is readily accessible for the corresponding high temperature liquids. It will be shown that information on each state … more
Date: May 6, 1977
Creator: Riebling, E.F.
Partner: UNT Libraries Government Documents Department
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Development of nondestructive evaluation methods and prediction of effects of flaws on the fracture behavior of structural ceramics

Description: Characterization of ceramic matrix composites (continuous and whisker-type) by nondestructive evaluation (NDE) methods and an understanding of fracture behavior, together with correlation of fracture and NDE data, may provide insight into the prediction of component performance and the development of process technology. Knowledge of the degradation extent of fiber tows or monofilament degradation after processing, extent of open porosity before densification, and filament/fiber alignments befor… more
Date: May 1, 1992
Creator: Ellingson, W.A.; Singh, J.P.; Holloway, D.L.; Dieckman, S.L.; Singh, D.; Sivers, E.A. et al.
Partner: UNT Libraries Government Documents Department
open access

Thyratron characteristics under high di/dt and high-repetition-rate operation

Description: Power conditioning systems for high peak and average power, high repetition rate discharge excited lasers involve operation of modulator components in unconventional regimes. Reliable operation of switches and energy storage elements under high voltage and high di/dt conditions is a pacing item for laser development at the present time. To test and evaluate these components a Modulator Component Test Facility (MCTF) was constructed. The MCTF consists of a command charge system, energy storage c… more
Date: May 11, 1981
Creator: Ball, D.; Hill, J. & Kan, T.
Partner: UNT Libraries Government Documents Department
open access

Some physical aspects of higher twist

Description: A brief description of some of the physical origins of higher twist terms and their possible relevance to data is given. 13 references, 7 figures.
Date: May 1, 1980
Creator: Blankenbecler, R.
Partner: UNT Libraries Government Documents Department
open access

Thick Target Neutron Yields and Spectra From the Li(d,xn) Reaction at 35 Mev

Description: Measurements were performed using a 35 MeV deuteron beam from the isochronous cyclotron at the University of California at Davis. Data were obtained using the time-of-flight technique with an NE213 liquid scintillator. One set of measurements was used to observe the neutron spectrum from approx. 1 MeV to approx. 50 MeV, the maximum kinematically allowed energy. Observation angles were from 0/sup 0/ to 150/sup 0/ with emphasis on forward angles. Spectral data below approx. 1.5 MeV had poor accur… more
Date: May 1, 1980
Creator: Johnson, D. L.; Mann, F. M.; Watson, J. W.; Brady, F. P.; Ullmann, J. L.; Romero, J. L. et al.
Partner: UNT Libraries Government Documents Department
open access

Frank loop unfaulting mechanism in fcc metals during neutron irradiation

Description: The unfaulting mechanism whereby sessile Frank dislocation loops evolve into a complex tangle of glissile dislocations during irradiation of face centered cubic metals is not well understood. It is presumed that such loops grow by absorption of point defects until interactions develop which provide sufficient impetus for nucleation of an unfaulting event. The loops then become glissile, interact and form a dislocation network. An alternate mechanism which has been observed to occur in an austen… more
Date: May 1980
Creator: Gelles, D. S.
Partner: UNT Libraries Government Documents Department
open access

Ripple burn control

Description: The ripple contribution to the ion thermal conductivity is ideally suited in magnitude, temperature dependence, and spatial dependence to serve as a burn control mechanism. Furthermore, a considerable measure of automatic burn control results because of the radial shift of the plasma to a region of higher ripple. Unfortunately, the window in ripple values consistent with both ignition and a burn equilibrium is uncomfortably narrow, given the current lack of contact between the theoretical model… more
Date: May 1, 1980
Creator: Bhadra, D. K.; Petrie, T. W.; Peuron, U. A. & Rawls, J. M.
Partner: UNT Libraries Government Documents Department
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W mass and W asymmetry at CDF

Description: The lepton charge asymmetry from W decaying into a lepton and a neutrino is discussed (preliminary result). This measurement gives information on parton distribution functions at low x values. The derivation of the recently published W mass value of 79.91 {plus minus} 0.39 GeV/c{sup 2} is also presented. M{sub W} is used to set an upper limit on the top quark mass. 13 refs., 4 figs., 1 tab.
Date: May 1, 1991
Creator: Leone, S. (Pisa Univ. (Italy) Istituto Nazionale di Fisica Nucleare, Pisa (Italy))
Partner: UNT Libraries Government Documents Department
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Determination of the composition of ordered Pt/sub 3/Co by atom-probe field-ion microscopy: intrinsic problems

Description: Atom-probe field-ion microscope (FIM) analyses were performed on specimens of fully ordered Pt/sub 3/Co. The purpose of the investigation was to study the effects of different important experimental variables on the composition measured by the atom probe technique. The dependence of the alloy's composition on the following variables was determined: (1) pulse fraction (f); (2) specimen temperature; (3) crystal plane; and (4) field-evaporation rate. It was demonstrated that the composition determ… more
Date: May 1, 1980
Creator: Yamamoto, M. & Seidman, D. N.
Partner: UNT Libraries Government Documents Department
open access

High-intensity photoionization of H sub 2

Description: A tunable, high-intensity picosecond dye laser system has been employed with electron energy analysis to investigate the dynamics of (3+1) resonance-enhanced multiphoton ionization of H{sub 2} via different vibrational levels of its B{sub 1}{Sigma}{sub u}{sup +} and C{sup 1}{Pi}{sub u} electronic states. We observe production of molecular ions in various vibrational levels, with a shift to increased population of lower vibrational states of H{sub 2}{sup +} consistent with the a.c. Stark shift o… more
Date: May 1, 1991
Creator: Allendorf, S.W. & Szoeke, A.
Partner: UNT Libraries Government Documents Department
open access

Whole facility energy use monitoring

Description: Pacific Northwest Laboratory (PNL) is conducting numerous field monitoring studies of the induces of energy in buildings. Energy use monitoring techniques have been developed to provide reliable empirical measurements of energy consumption according to enduse and time of day. These measurements are analyzed in conjunction with climate and site characteristics data to determine energy use efficiencies and identify energy conservation and load management opportunities. This paper draws upon this … more
Date: May 1, 1989
Creator: Mazzucchi, R.P. & Jo, J.
Partner: UNT Libraries Government Documents Department
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