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Improved solid-state laser sources. Final technical report, 2 June 1981-1 June 1982

Description: During the first program year we have demonstrated diffraction limited output of 600 mJ from an unstable resonator Nd:Glass slab geometry oscillator. We have investigated, in detail, slab geometry lasers and have verified by careful experiments all important predictions of the slab theory. To date we have generated 10 J of output energy at 2.5 Hz from a single multimode, non-Q-switched, slab oscillator at 3.5% storage efficiency, 2% slope efficiency and 1.6% extraction efficiency. We have doubl… more
Date: August 1, 1982
Creator: Byer, R.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Maximum Size of Combinatorial Geometries Excluding Wheels and Whirls as Minors

Description: We show that the maximum size of a geometry of rank n excluding the (q + 2)-point line, the 3-wheel W_3, and the 3-whirl W^3 as minor is (n - 1)q + 1, and geometries of maximum size are parallel connections of (q + 1)-point lines. We show that the maximum size of a geometry of rank n excluding the 5-point line, the 4-wheel W_4, and the 4-whirl W^4 as minors is 6n - 5, for n ≥ 3. Examples of geometries having rank n and size 6n - 5 include parallel connections of the geometries V_19 and PG(2,3).
Date: August 1989
Creator: Hipp, James W. (James William), 1956-
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Understanding Ancient Math Through Kepler: A Few Geometric Ideas from The Harmony of the World

Description: Euclid's geometry is well-known for its theorems concerning triangles and circles. Less popular are the contents of the tenth book, in which geometry is a means to study quantity in general. Commensurability and rational quantities are first principles, and from them are derived at least eight species of irrationals. A recently republished work by Johannes Kepler contains examples using polygons to illustrate these species. In addition, figures having these quantities in their construction f… more
Date: August 2002
Creator: Arthur, Christopher
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Neutral Beam Injection for Plasma and Magnetic FieldDiagnostics

Description: At the Lawrence Berkeley National Laboratory (LBNL) adiagnostic neutral beam injection system for measuring plasma parameters,flow velocity, and local magnetic field is being developed. High protonfraction and small divergence is essential for diagnostic neutral beams.In our design, a neutral hydrogen beam with an 8 cm x 11 cm (or smaller)elliptical beam spot at 2.5 m from the end of the extraction column isproduced. The beam will deliver up to 5 A of hydrogen beam to the targetwith a pulse wid… more
Date: August 1, 2007
Creator: Vainionpaa, Jaakko Hannes; Leung, Ka Ngo; Kwan, Joe W. & Levinton,Fred
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy Design Plugin: An EnergyPlus Plugin for SketchUp; Preprint

Description: This paper describes the Energy Design Plugin, a new software plugin that aims to integrate simulation as a tool during the earliest phases of the design process. The plugin couples the EnergyPlus whole-building simulation engine to the Google SketchUp drawing program.
Date: August 1, 2008
Creator: Ellis, P. G.; Torcellini, P. A. & Crawley, D. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SOME NATURAL CONDUIT ANALOGUES FOR POTENTIAL IGNEOUS ACTIVITY AT YUCCA MOUNTAIN

Description: Eruptive conduit geometry has direct relation to number of waste packages that would be damaged if a new volcano were to form at the proposed Yucca Mountain radioactive waste repository, and therefore is a key factor in predicting the consequences of such an eruption. Current risk calculations treat conduits as having circular plan view and range from a few meters to 150 m diameter at repository depths ({approx}300 m). We present new observations of shallow basaltic plumbing at analog sites aim… more
Date: August 26, 2005
Creator: Krier, D.J.; Keating, G.N. & Valentine, G.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydra modeling of experiments to study ICF capsule fill hole dynamics using surrogate targets

Description: In this section the results of HYDRA [1] design simulations will be discussed. The simulations were conducted in two dimensional, RZ geometry, with the fill tube on axis. The radiation transport was treated in the diffusion approximation using 15 energy groups. Opacities were calculated. The equations of state (EOS) for all materials used were from a combined analytic/Thomas-Fermi EOS which uses a modified Cowan model for the ion EOS, and uses a scaled Thomas-Fermi table for the electron EOS.
Date: August 27, 2007
Creator: Elliott, J B
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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VERIFICATION TEST PROBLEMS

Description: We present analytic solutions to two test problems that can be used to check the hydrodynamic implementation in computer codes designed to calculate the propagation of shocks in spherically convergent geometry. Our analysis is restricted to fluid materials with constant bulk modulus. In the first problem we present the exact initial acceleration and pressure gradient at the outer surface of a sphere subjected to an exponentially decaying pressure of the form P(t) = P{sub 0}e{sup -at}. We show t… more
Date: August 8, 2007
Creator: Moran, B
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Criticality Evaluation of Plutonium-239 Moderated by High-Density Polyethylene in Stainless Steel and Aluminum Containers Suitable for Non-Exclusive Use Transport

Description: Research is conducted at the Joint Actinide Shock Physics Experimental Facility (JASPER) on the effects of high pressure and temperature environments on plutonium-239, in support of the stockpile stewardship program. Once an experiment has been completed, it is necessary to transport the end products for interim storage or final disposition. Federal shipping regulations for nonexclusive use transportation require that no more than 180 grams of fissile material are present in at least 360 kilogr… more
Date: August 10, 2007
Creator: Watson, T T
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Test Results of a Nb3Sn Wind/React 'Stress-Managed' BlockDipole

Description: A second phase of a highfield dipole technology developmenthas been tested. A Nb3Sn block-coil model dipole was fabricated, usingmagnetic mirror geometry and wind/react coil technology. The primaryobjective of this phase was to make a first experimental test of thestress-management strategy pioneered at Texas A&M. In this strategy ahigh-strength support matrix is integrated with the windings to interceptLorentz stress from the inner winding so that it does not accumulate inthe outer winding. Th… more
Date: August 25, 2006
Creator: McInturff, A.; Bish, P.; Blackburn, R.; Diaczenko, N.; Elliott,T.; Hafalia Jr., R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The application of front tracking to the simulation of shock refractions and shock accelerated interface mixing

Description: The mixing behavior of two or more fluids plays an important role in a number of physical processes and technological applications. The authors consider two basic types of mechanical (i.e., non-diffusive) fluid mixing. If a heavy fluid is suspended above a lighter fluid in the presence of a gravitational field, small perturbations at the fluid interface will grow. This process is known as the Rayleigh-Taylor instability. One can visualize this instability in terms of bubbles of the light fluid … more
Date: August 1, 1993
Creator: Sharp, D. H.; Grove, J. W.; Yang, Y.; Boston, B.; Holmes, R.; Zhang, Q. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Diffraction tomographic signal processing algorithms for tunnel detection

Description: Signal processing algorithms have been developed for wave based imaging using diffraction tomography. The basis for this image reconstruction procedure is the generalized projection slice theorem (GPST) which, for homogeneous waves, is an analytic relationship between the spatial Fourier transform of the acquired data and the spatial Fourier transform of the spatial profile (object function) of the object being imaged. Imaging within geophysical diffraction tomography when only homogeneous wave… more
Date: August 1, 1993
Creator: Witten, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Triangle: A Teaching Program of High School Geometry

Description: Among the early applications of computers, one can find frequent mention of intelligent instructional systems. Such intelligent instructional systems represent a new generation of learner-based computer aided instruction, preceded in time by the original frame-based systems and an intervening generation of expert-based CAI. The history of CAI is characterized by three generations: Frame-based CAI, Expert-based CAI and Learner-based CAI.
Date: August 1983
Creator: Chen, Yei-Huang
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Design considerations for high-current superconducting RFQ,s

Description: As part of our ongoing development program of high-current cw accelerators, we are investigating the use of superconducting RFQs to capture, bunch, and accelerate high-current, cw ion beams to energies where they can be further accelerated by more conventional independently-coupled superconducting cavities. This investigation addresses issues related to beam physics, thermal management, electromagnetic design, mechanical design, matching to the ion source, etc.
Date: August 1, 1993
Creator: Delayen, J. R.; Bohn, C. L.; Kennedy, W. L. & Sagalovsky, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Entangled States, Holography and Quantum Surfaces

Description: Starting with an elementary discussion of quantum holography, we show that entangled quantum states of qubits provide a ''local'' representation of the global geometry and topology of quantum Riemann surfaces. This representation may play an important role in both mathematics and physics. Indeed, the simplest way to represent the fundamental objects in a ''theory of everything'' may be as muti-qubit entangled states.
Date: August 13, 2003
Creator: Chapline, G F
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Numerical investigation of the thrust efficiency of a laser propelled vehicle

Description: The flow situation for a thruster propelled by ablated gas which is energized by a laser pulse is numerically simulated. The flow is axisymmetric and nonsteady, and is assumed to be inviscid due to its high Reynolds number. The high pressure expansion of the laser heated gas generates thrust as it pushes against the vehicle. Gas expansion lateral to the thrust vector causes performance to decrease. The vehicle geometry and the laser pulse characteristics determine the degree to which the flow i… more
Date: August 1, 1990
Creator: jr, mulroy
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electronic structure and spectroscopy of nucleic acid bases: Ionization energies, ionization-induced structural changes, and photoelectron spectra

Description: We report high-level ab initio calculations and single-photon ionization mass spectrometry study of ionization of adenine (A), thymine (T), cytosine (C) and guanine (G). For thymine and adenine, only the lowest-energy tautomers were considered, whereas for cytosine and guanine we characterized five lowest-energy tautomeric forms. The first adiabatic and several vertical ionization energies were computed using equation-of-motion coupled-cluster method for ionization potentials with single and do… more
Date: August 2, 2010
Creator: Bravaya, Ksenia B.; Kostko, Oleg; Dolgikh, Stanislav; Landau, Arie; Ahmed, Musahid & Krylov, Anna I.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Search for backwards produced exotic meson resonances and study of particle spectra and mass distributions in the reaction. pi. /sup +/ + P. -->. n (forward) + X/sup + +/ at 8. 4 GeV/c. [Upper limits, G parity, 8. 4 GeV/c]

Description: Results are reported from a hybrid experiment designed to search for backwards produced I = 2 exotic meson resonances by investigating the backward scattering reactions: ..pi../sup +/ + p ..-->.. in (forward) + ..pi../sup +/..pi../sup +/, ..pi../sup +/..pi../sup +/..pi../sup +/..pi../sup -/, ..pi../sup +/..pi../sup +/..pi../sup +/..pi../sup +/..pi../sup -/..pi../sup -/, and p anti p..pi../sup +/..pi../sup +/ at an incident pion momentum of 8.4 GeV/c. The SLAC 15'' rapid cycling bubble chamber, … more
Date: August 1, 1975
Creator: Alam, M. S.; Brabson, B. B. & Galloway, K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isospin Splittings of Doubly Heavy Baryons

Description: The SELEX Collaboration has reported a very large isospin splitting of doubly charmed baryons. We show that this effect would imply that the doubly charmed baryons are very compact. One intriguing possibility is that such baryons have a linear geometry Q-q-Q where the light quark q oscillates between the two heavy quarks Q, analogous to a linear molecule such as carbon dioxide. However, using conventional arguments, the size of a heavy-light hadron is expected to be around 0.5 fm, much larger t… more
Date: August 18, 2011
Creator: Brodsky, Stanley J.; Guo, Feng-Kun; Hanhart, Christoph & Meissner, Ulf-G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Array of virtual Frisch-grid CZT detectors with common cathode readout and pulse-height correction

Description: We present our new results from testing 15-mm-long virtual Frisch-grid CdZnTe detectors with a common-cathode readout for correcting pulse-height distortions. The array employs parallelepiped-shaped CdZnTe (CZT) detectors of a large geometrical aspect ratio, with two planar contacts on the top and bottom surfaces (anode and cathode) and an additional shielding electrode on the crystal's sides to create the virtual Frisch-grid effect. We optimized the geometry of the device and improved its spec… more
Date: August 1, 2010
Creator: Bolotnikov, A. E.; Camarda, G. S.; Cui, Y.; Egarievwe, E. U.; Fochuk, P. M.; Fuerstnau, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Specification for the Reattachment of the EC South Cryostat Heads

Description: This Engineering Note defines technical requirements and the scope of work for reattachment of the heads of the South EC cryostat. This work is to be done in the clean room at the D-Zero Assembly Building (DAB) at Fermilab.and is expected to begin around September 15, 1991. The task consists primarily of welding four heads onto a 17-foot diameter stainless steel double-wall pressure/vacuum vessel. Nominal thicknesses of the welds are all 5/8-inch. Root passes are to be made by TIG welding and t… more
Date: August 1, 1991
Creator: Luther, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On the behavior of Bronsted-Evans-Polanyi Relations for Transition Metal Oxides

Description: Versatile Broensted-Evans-Polanyi (BEP) relations are found from density functional theory for a wide range of transition metal oxides including rutiles and perovskites. For oxides, the relation depends on the type of oxide, the active site and the dissociating molecule. The slope of the BEP relation is strongly coupled to the adsorbate geometry in the transition state. If it is final state-like the dissociative chemisorption energy can be considered as a descriptor for the dissociation. If it … more
Date: August 22, 2011
Creator: Vojvodic, Aleksandra
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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