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Review of Gamification mindset (open access)

Review of Gamification mindset

This article is a review of the book "Gamification Mindset" by Ole Goethe.
Date: October 15, 2020
Creator: Ham, Chris D.
System: The UNT Digital Library
The hygroscopicity of moso bamboo (Phyllostachys edulis) with a gradient fiber structure (open access)

The hygroscopicity of moso bamboo (Phyllostachys edulis) with a gradient fiber structure

This article studies the hygroscopicity of moso bamboo (Phyllostachys edulis) with a gradient fiber structure assessed by a dynamic vapor sorption (DVS) apparatus and fitted with a Haillwood–Horrobin (H–H) model. The effects of the chemical composition, gradient fiber structure, and mesopore structure of the bamboo were also investigated. The results demonstrate that the hygroscopicity of bamboo gradually increases from the outer to the inner layer along the thickness of the culm wall, which is related to the gradient distribution of the fibers. The structure–function relationships between the chemical composition, multi-scale structure, and hygroscopicity identified in this study provide a theoretical basis for bamboo drying and storage technology, as well as the processing and application of bamboo fiber-based composites.
Date: October 15, 2021
Creator: Wei, Xin; Wang, Ge; Smith, Lee M. & Jiang, Huan
System: The UNT Digital Library
Safety and environmental aspects of fusion reactors (open access)

Safety and environmental aspects of fusion reactors

Fusion is examined against the yardstick of fission technology with respect to inventories of radioactivity (and associated Biological Hazard Potentials), routine emissions, accident pathways and consequences, radioactive-waste management, and misuse of nuclear materials. Based on conceptual designs of Tokamak fusion reactors with stainless steel structure and tritium inventories of 10 kg per thermal gigawatt, the apparent advantage of fusion is 1 to 2 orders of magnitude in most indices of radiological hazards. Fusion's advantage is 2 to 5 orders of magnitude in comparing damage potential of intentional airborne dispersal of tritium and plutonium, and nonexistent in comparing medium-term radwaste hazard potential (1000 to 100,000 years) and intentional waterborne dispersal of tritium and plutonium. Fusion appears to have some qualitative advantages with respect to accident pathways and safeguards considerations. Fusion has the theoretical potential for improvements of 1 to 2 additional orders of magnitude in short-term BHPs and 3 orders of magnitude and more in radwaste BHPs after 10 years if vanadium-titanium alloy can be used in place of stainless steel in the reactor structure. Other important unresolved questions are how much the inventory of tritium can be reduced by ingenious design, and what fraction of a fusion reactor's activation products …
Date: October 15, 1976
Creator: Holdren, J. P.
System: The UNT Digital Library
X-ray detector calibrations in the 183- to 932-eV energy range (open access)

X-ray detector calibrations in the 183- to 932-eV energy range

The absolute sensitivities of several different types of x-ray detectors were measured between 183 eV and 932 eV. The photons in this energy range were produced by bombarding thin, water-cooled, metal targets with protons from a Cockcroft-Walton ion accelerator. The detectors measured included a silicon-semiconductor detector, two photoelectric-diode detectors employing aluminum and gold photocathodes, and three detectors incorporating plastic scintillators and photodiodes.
Date: October 15, 1976
Creator: Gaines, J. L. & Ernst, R. D.
System: The UNT Digital Library
The Wavefront Control System for the National Ignition Facility (open access)

The Wavefront Control System for the National Ignition Facility

The National Ignition Facility (NIF) requires that pulses from each of the 192 laser beams be positioned on target with an accuracy of 50 {micro}m rms. Beam quality must be sufficient to focus a total of 1.8 MJ of 0.351-{micro}m light into a 600-{micro}m-diameter volume. An optimally flat beam wavefront can achieve this pointing and focusing accuracy. The control system corrects wavefront aberrations by performing closed-loop compensation during laser alignment to correct for gas density variations. Static compensation of flashlamp-induced thermal distortion is established just prior to the laser shot. The control system compensates each laser beam at 10 Hz by measuring the wavefront with a 77-lenslet Hartmann sensor and applying corrections with a 39-actuator deformable mirror. The distributed architecture utilizes SPARC AXi computers running Solaris to perform real-time image processing of sensor data and PowerPC-based computers running VxWorks to compute mirror commands. A single pair of SPARC and PowerPC processors accomplishes wavefront control for a group of eight beams. The software design uses proven adaptive optic control algorithms that are implemented in a multi-tasking environment to economically control the beam wavefronts in parallel. Prototype tests have achieved a closed-loop residual error of 0.03 waves rms. aberrations, the spot size …
Date: October 15, 2001
Creator: Van Atta, L.; Perez, M.; Zacharias, R. & Rivera, W.
System: The UNT Digital Library
Determination of Partial (N,Xngamma) Cross-Sections in 193-Ir (open access)

Determination of Partial (N,Xngamma) Cross-Sections in 193-Ir

The {sup 193}Ir(n,n'){sup 193m}Ir cross section for the production of the 80-keV isomer in {sup 193}Ir is evaluated using a combination of experimental data and nuclear reaction modeling, from threshold to about 20 MeV. Four discrete {gamma} lines feeding the isomer were recently observed with the GEANIE {gamma}-ray detector at LANSCE. Theoretical calculations of the nuclear reaction mechanisms in play are then carried out to evaluate the contributions not accounted for in the experimental setup (direct population; fraction of {gamma}-lines not observed in the experiment; etc). Experiment and modeling are then combined to provide a total cross section for the production of the Iridium isomer. We finally compare our result with activation measurement data available for a few energy points.
Date: October 15, 2003
Creator: Talou, P.; Chadwick, M. B.; Nelson, R.; Fotiades, N.; Devlin, M.; Garrett, P. E. et al.
System: The UNT Digital Library
Gamma rays emitted in the decay of 31-year 178m2Hf (open access)

Gamma rays emitted in the decay of 31-year 178m2Hf

The spontaneous decay of the K{sup {pi}} = 16{sup +}, 31-year {sup 178m2}Hf isomer has been investigated with a 15 kBq source placed at the center of a 20-element {gamma}-ray spectrometer. High-multipolarity M4 and E5 transitions, which represent the first definitive observation of direct {gamma}-ray emission from the isomer, have been identified, together with other low-intensity transitions. Branching ratios for these other transitions have elucidated the spin dependence of the mixing between the two known K{sup {pi}} = 8{sup -} bands. The M4 and E5 {gamma}-ray decays are the first strongly K-forbidden transitions to be identified with such high multipolarities, and demonstrate a consistent extension of K-hindrance systematics, with an inhibition factor of approximately 100 per degree of K forbiddenness. Some unplaced transitions are also reported.
Date: October 15, 2003
Creator: MB, S; PW, W; GC, B; JJ, C; PE, G; G, H et al.
System: The UNT Digital Library
Improved Operation and Modeling of the SSPX Spheromak (open access)

Improved Operation and Modeling of the SSPX Spheromak

None
Date: October 15, 2004
Creator: Wood, R. D.; Cohen, B. I.; Hill, D. N.; Cohen, R. H.; Woodruff, S.; McLean, H. S. et al.
System: The UNT Digital Library
Nuclear Proliferation Using Laser Isotope Separation -- Verification Options (open access)

Nuclear Proliferation Using Laser Isotope Separation -- Verification Options

Two levels of nonproliferation verification exist. Signatories of the basic agreements under the Nuclear Non-proliferation Treaty (NPT) agree to open their nuclear sites to inspection by the IAEA. A more detailed and intrusive level was developed following the determination that Iraq had begun a nuclear weapons development program that was not detected by the original level of verification methods. This level, referred to as 93+2 and detailed in model protocol INFCIRC/540, allows the IAEA to do environmental monitoring of non-declared facilities that are suspected of containing proliferation activity, and possibly further inspections, as well as allowing more detailed inspections of declared sites. 56 countries have signed a Strengthened Safeguards Systems Additional Protocol as of 16 July 2001. These additional inspections can be done on the instigation of the IAEA itself, or after requests by other parties to the NPT, based on information that they have collected. Since information able to cause suspicion of proliferation could arrive at any country, it is important that countries have procedures in place that will assist them in making decisions related to these inspections. Furthermore, IAEA inspection resources are limited, and therefore care needs to be taken to make best use of these resources. Most …
Date: October 15, 2001
Creator: Erickson, S A
System: The UNT Digital Library
Astrometry with the MACHO Data Archive (open access)

Astrometry with the MACHO Data Archive

We present the preliminary results of our astrometric study of stellar motions along the lines of sight of the Magellanic Clouds and the Galactic bulge. We find that we are able to select stars with proper motions as small as 0.03 inch/yr from five years of PSF photometry due to the characteristic nature of the shapes the light curves of HFM stars. This shape arises from the proper motion of the object relative to the initial fixed centroid location where all photometry of the object is performed. By selecting such light curves and performing astrometry on candidate HPM stars we have discovered 154 new high proper motion (HPM) stars in 50{sup {open_square}}{sup o} from amongst the {approx} 55 million of stars observed by the MACHO project in these fields. These objects have proper motions as high as 0.5 inch/yr, luminosities ranging from V {approx} 13 to V {approx} 19, and V-R colours between 0.3 and 1.45.
Date: October 15, 2000
Creator: Drake, A. J.; Alcock, C.; Allsman, R.; Alves, D. R.; Axelrod, T. S.; Becker, A. C. et al.
System: The UNT Digital Library
Vibrational and intruder structures in 116Cd: a conundrum (open access)

Vibrational and intruder structures in 116Cd: a conundrum

Decay properties of multiphonon quadropole vibrational states and intruder structures in {sup 116}Cd have been examined with the (n,n'{gamma}) reaction. Gamma-ray excitation functions, angular distributions and {gamma}-{gamma} coincidences have been measured. Lifetimes of many levels were determined with the Doppler-shift attenuation method, exposing the degree of collectivity of the intruder structure and the three-phonon states. In combination with other recent results, this new information reveals that the intruder picture is well supported in the Cd nuclei. However, a conundrum not present in the lighter cadmium nuclei emerges in {sup 116}Cd; strong configuration mixing between intruder and multiphonon vibrational excitations cannot describe the observed decays of the lowest 0{sup +} excited states.
Date: October 15, 2003
Creator: M., K; N, W; PE, G; J, J & SW, Y
System: The UNT Digital Library
Summary of Synthetic Lap Polishing Experiments at LLNL, FY95 (open access)

Summary of Synthetic Lap Polishing Experiments at LLNL, FY95

The purpose of this research was to support the optics finishing development work for the NIF, the National Ignition Facility. One of the major expenses for the construction of NIF is the cost of finishing of the large aperture optics. One way to significantly reduce the cost of the project is to develop processes to reduce the amount of time necessary to polish the more than 3,000 amplifier slabs. These slabs are rectangular with an aspect ratio of more than twenty to one and are made of a very temperature sensitive glass, Nd doped phosphate laser glass. As a result of this effort, we could potentially reduce the time necessary to polish each surface of an amplifier from 20-30 hours of run time to under an hour to achieve the same removal and still maintain a flatness of between one to three waves concave figure. We also feel confident that we can polish rectangular thermally sensitive glass flat by use of temperature control of the polishing platen, pad curvature, slurry concentration with temperature control, pad rotation, and pressure; although further, larger scale experiments are necessary to gain sufficient confidence that such a procedure could be successfully fielded.
Date: October 15, 2001
Creator: Nichols, M A
System: The UNT Digital Library
The Overview of the National Ignition Facility Distributed Computer Control System (open access)

The Overview of the National Ignition Facility Distributed Computer Control System

The Integrated Computer Control System (ICCS) for the National Ignition Facility (NIF) is a layered architecture of 300 front-end processors (FEP) coordinated by supervisor subsystems including automatic beam alignment and wavefront control, laser and target diagnostics, pulse power, and shot control timed to 30 ps. FEP computers incorporate either VxWorks on PowerPC or Solaris on UltraSPARC processors that interface to over 45,000 control points attached to VME-bus or PCI-bus crates respectively. Typical devices are stepping motors, transient digitizers, calorimeters, and photodiodes. The front-end layer is divided into another segment comprised of an additional 14,000 control points for industrial controls including vacuum, argon, synthetic air, and safety interlocks implemented with Allen-Bradley programmable logic controllers (PLCs). The computer network is augmented asynchronous transfer mode (ATM) that delivers video streams from 500 sensor cameras monitoring the 192 laser beams to operator workstations. Software is based on an object-oriented framework using CORBA distribution that incorporates services for archiving, machine configuration, graphical user interface, monitoring, event logging, scripting, alert management, and access control. Software coding using a mixed language environment of Ada95 and Java is one-third complete at over 300 thousand source lines. Control system installation is currently under way for the first 8 beams, …
Date: October 15, 2001
Creator: Lagin, L J; Bettenhausen, R C; Carey, R A; Estes, C M; Fisher, J M; Krammen, J E et al.
System: The UNT Digital Library
Determining the sign of the b ---> s gamma amplitude (open access)

Determining the sign of the b ---> s gamma amplitude

None
Date: October 15, 2004
Creator: Gambino, Paolo; Haisch, Ulrich & Misiak, Mikolaj
System: The UNT Digital Library
Measurement of the Polarization of the K(Beta)2 Line of Helium-like V21+ (open access)

Measurement of the Polarization of the K(Beta)2 Line of Helium-like V21+

We have measured the polarization of the intercombination line 1s3p {sup 3}P{sub 1}-1s{sup 2}{sup 1}S{sub 0}, the so called K{beta}2 line, in helium-like V{sup 21+} using two Bragg crystal spectrometers. The ions were excited in the Lawrence Livermore National Laboratory electron beam ion trap. We find values which are not significantly different from theoretical predictions based on some admixing of the initial state by the hyperfine interaction. In this short paper we present our results.
Date: October 15, 2001
Creator: Smith, A. J.; Beiersdorfer, P.; Wong, K. L. & Reed, K. J.
System: The UNT Digital Library
EVALUATION OF AN IMPROVED CONVECTION TRIGGERING MECHANISM IN THE NCAR COMMUNITY ATMOSPHERE MODEL CAM2 UNDER CAPT FRAMEWORK (open access)

EVALUATION OF AN IMPROVED CONVECTION TRIGGERING MECHANISM IN THE NCAR COMMUNITY ATMOSPHERE MODEL CAM2 UNDER CAPT FRAMEWORK

The problem that convection over land is overactive during warm-season daytime in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model CAM2 and its previous version (CCM3) has been found both in its single-column model (SCM) simulations (Xie and Zhang 2000; Ghan et al. 2000; Xie et al. 2002) and in its full general circulation model (GCM) short-range weather forecasts (Phillips et al. 2003) and climate simulations (Dai and Trenberth 2003). These studies showed that this problem is closely related to the convection triggering mechanism used in its deep convection scheme (Zhang and McFarlane 1995), which assumes that convection is triggered whenever there is positive convective available potential energy (CAPE). The positive CAPE triggering mechanism initiates model convection too often during the day because of the strong diurnal variations in the surface isolation and the induced CAPE diurnal change over land in the warm season. To reduce the problem, Xie and Zhang (2000) introduced a dynamic constraint, i.e., a dynamic CAPE generation rate (DCAPE) determined by the large-scale advective tendencies of temperature and moisture, to control the onset of deep convection. They showed that positive DCAPE is closely associated with convection in observations and the dynamic constraint could largely …
Date: October 15, 2003
Creator: Xie, S; Boyle, J S; Cederwall, R T; Potter, G L & Zhang, M
System: The UNT Digital Library
VELOCITY BUNCHING OF HIGH-BRIGHTNESS ELECTRON BEAMS (open access)

VELOCITY BUNCHING OF HIGH-BRIGHTNESS ELECTRON BEAMS

Velocity bunching has been recently proposed as a tool for compressing electron beam pulses in modern high brightness photoinjector sources. This tool is familiar from earlier schemes implemented for bunching dc electron sources, but presents peculiar challenges when applied to high current, low emittance beams from photoinjectors. The main difficulty foreseen is control of emittance oscillations in the beam in this scheme, which can be naturally considered as an extension of the emittance compensation process at moderate energies. This paper presents two scenarios in which velocity bunching, combined with emittance control, is to play a role in nascent projects. The first is termed ballistic bunching, where the changing of relative particle velocities and positions occur in distinct regions, a short high gradient linac, and a drift length. This scenario is discussed in the context of the proposed ORION photoinjector. Simulations are used to explore the relationship between the degree of bunching, and the emittance compensation process. Experimental measurements performed at the UCLA Neptune Laboratory of the surprisingly robust bunching process, as well as accompanying deleterious transverse effects, are presented. An unanticipated mechanism for emittance growth in bends for highly momentum chirped beam was identified and studied in these experiments. The …
Date: October 15, 2004
Creator: Anderson, S. G.; Musumeci, P.; Rosenzweig, J. B.; Brown, W. J.; England, R. J.; Ferrario, M. et al.
System: The UNT Digital Library
Integrated Chemical Systems: The Simultaneous Formation of Hybrid Nanocomposites of Iron Oxide and Organo Silsesquioxanes (open access)

Integrated Chemical Systems: The Simultaneous Formation of Hybrid Nanocomposites of Iron Oxide and Organo Silsesquioxanes

A sol-gel approach for the synthesis of hybrid nanocomposites of iron oxide and bridged polysilsesquioxanes has been established. The procedures allow for the simultaneous formation of iron oxide and polysilsesquioxane networks in monolithic xerogels and aerogels. These hybrid nanocomposites are synthesized from FeCl{sub 3} {center_dot} 6H{sub 2}O and functionalized silsesquioxane monomers in a one-pot reaction using epoxides as a gelation agent. The porosity and microstructure of the materials has been determined by nitrogen porosimetry, electron microscopy and ultra small angle X-ray scattering (USAXS). The hybrid nanocomposites exhibit a uniform dispersion of both components with no evidence for phase separation at length scales > 5 nm. At this limit of resolution it is not possible to distinguish between two independent interpenetrating networks integrated at molecular length scales or a random copolymer or mixtures of both.
Date: October 15, 2004
Creator: Zhao, Lihua; Clapsaddle, Brady J.; Satcher, Joe H., Jr.; Schaefer, Dale W. & Shea, Kenneth J.
System: The UNT Digital Library
Resonance Neutron Coincidence capture y-ray Spectra in W{sup184} (open access)

Resonance Neutron Coincidence capture y-ray Spectra in W{sup184}

None
Date: October 15, 1963
Creator: unknown
System: The UNT Digital Library
Large Space Telescopes Using Fresnel Lens for Power Beaming, Astronomy and Sail Missions (open access)

Large Space Telescopes Using Fresnel Lens for Power Beaming, Astronomy and Sail Missions

The concept of using Fresnel optics as part of power beaming, astronomy or sail systems has been suggested by several authors. The primary issues for large Fresnel optics are the difficulties in fabricating these structures and deploying them in space and for astronomy missions the extremely narrow frequency range of these optics. In proposals where the telescope is used to transmit narrow frequency laser power, the narrow bandwidth has not been an issue. In applications where the optic is to be used as part of a telescope, only around 10{sup -5} to limited frequency response of a Fresnel optic is addressed by the use of a corrective optic that will broaden the frequency response of the telescope by three or four orders of magnitude. This broadening will dramatically increase the optical power capabilities of the system and will allow some spectroscopy studies over a limited range. Both the fabrication of Fresnel optics as large as five meters and the use of corrector optics for telescopes have been demonstrated at LLNL. For solar and laser sail missions the use of Fresnel amplitude zone plates made of very thin sail material is also discussed.
Date: October 15, 2002
Creator: Early, J T
System: The UNT Digital Library
The gamma knife: Dose and risk evaluation (open access)

The gamma knife: Dose and risk evaluation

This paper outlines a risk analysis approach designed to identify and assess most likely failure modes and high-risk, human initiated actions for nuclear medical devices. This approach is being developed under the auspices of the US Nuclear Regulatory Commission, Office of Nuclear Material Safety and Safeguards. The methodology is initiated intended to assess risk associated with the use of the Leksell Gamma Unit (LGU) or gamma knife, a gamma stereotactic radiosurgical device.
Date: October 15, 1992
Creator: Jones, E. D.; Alesso, H. P.; Banks, W. W. & Rathbun, P. A.
System: The UNT Digital Library
System response of a DOE Defense Program package in a transportation accident environment (open access)

System response of a DOE Defense Program package in a transportation accident environment

The system response in a transportation accident environment is an element to be considered in an overall Transportation System Risk Assessment (TSRA) framework. The system response analysis uses the accident conditions and the subsequent accident progression analysis to develop the accident source term, which in turn, is used in the consequence analysis. This paper proposes a methodology for the preparation of the system response aspect of the TSRA.
Date: October 15, 1992
Creator: Chen, T. F.; Hovingh, J. & Kimura, C. Y.
System: The UNT Digital Library
Transportation System Risk Assessment on DOE Defense Program shipments (open access)

Transportation System Risk Assessment on DOE Defense Program shipments

Substantial effort has been expended concerning the level of safety provided to persons, property, and the environment from the hazards associated with transporting radioactive material. This work provided an impetus for the Department of Energy to investigate the use of probabilistic risk assessment techniques to supplement the deterministic approach to transportation safety. The DOE recently decided to incorporate the methodologies associated with PRAs in the process for authorizing the transportation of nuclear components, special assemblies, and radioactive materials affiliated with the DOE Defense Program. Accordingly, the LLNL, sponsored by the DOE/AL, is tasked with developing a safety guide series to provide guidance to preparers performing a transportation system risk assessment.
Date: October 15, 1992
Creator: Brumburgh, G. P.; Kimura, C. Y.; Alesso, H. P. & Prassinos, P. G.
System: The UNT Digital Library
Safety questions relevant to nuclear thermal propulsion (open access)

Safety questions relevant to nuclear thermal propulsion

Nuclear propulsion is necessary for successful Mars exploration to enhance crew safety and reduce mission costs. Safety concerns are considered by some to be an implements to the use of nuclear thermal rockets for these missions. Therefore, an assessment was made of the various types of possible accident conditions that might occur and whether design or operational solutions exist. With the previous work on the NERVA nuclear rocket, most of the issues have been addressed in some detail. Thus, a large data base exist to use in an agreement. The assessment includes evaluating both ground, launch, space operations and disposal conditions. The conclusion is that design and operational solutions do exist for the safe use of nuclear thermal rockets and that both the environment and crews be protected against harmful radiation. Further, it is concluded that the use of nuclear thermal propulsion will reduce the radiation and mission risks to the Mars crews.
Date: October 15, 1991
Creator: Buden, D.
System: The UNT Digital Library