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Derivation of the evolution of empathic other-regarding social emotions as compared to non-social self-regarding emotions (open access)

Derivation of the evolution of empathic other-regarding social emotions as compared to non-social self-regarding emotions

Article accompanying a poster presentation for the 2012 Computational Neuroscience Annual Meeting. This article discusses the derivation of the evolution of empathic other-regarding social emotions as compared to non-social self-regarding emotions.
Date: July 16, 2012
Creator: Tam, Nicoladie D.
System: The UNT Digital Library
The role of rare-earth dopants in nanophase zirconia catalysts for automotive emission control. (open access)

The role of rare-earth dopants in nanophase zirconia catalysts for automotive emission control.

Rare earth (RE) modification of automotive catalysts (e.g., ZrO{sub 2}) for exhaust gas treatment results in outstanding improvement of the structural stability, catalytic functions and resistance to sintering at high temperatures. Owing to the low redox potential of nonstoichiometric CeO{sub 2}, oxygen release and intake associated with the conversion between the 3+ and 4+ oxidation states of the Ce ions in Ce-doped ZrO{sub 2} provide the oxygen storage capacity that is essentially to effective catalytic functions under dynamic air-to-fuel ratio cycling. Doping tripositive RE ions such as La and Nd in ZrO{sub 2}, on the other hand, introduces oxygen vacancies that affect the electronic and ionic conductivity. These effects, in conjunction with the nanostructure and surface reactivity of the fine powders, present a challenging problem in the development of better ZrO{sub 2}-containing three-way catalysts. We have carried out in-situ small-to-wide angle neutron diffraction at high temperatures and under controlled atmospheres to study the structural phase transitions, sintering behavior, and Ce{sup 3+} {leftrightarrow} Ce{sup 4+} redox process. We found substantial effects due to RE doping on the nature of aggregation of nanoparticles, defect formation, crystal phase transformation, and metal-support interaction in ZrO{sub 2} catalysts for automotive emission control.
Date: July 16, 1999
Creator: Loong, C.-K. & Ozawa, M.
System: The UNT Digital Library
Commercial viability of hybrid vehicles : best household use and cross national considerations. (open access)

Commercial viability of hybrid vehicles : best household use and cross national considerations.

Japanese automakers have introduced hybrid passenger cars in Japan and will soon do so in the US. In this paper, we report how we used early computer simulation model results to compare the commercial viability of a hypothetical near-term (next decade) hybrid mid-size passenger car configuration under varying fuel price and driving patterns. The fuel prices and driving patterns evaluated are designed to span likely values for major OECD nations. Two types of models are used. One allows the ''design'' of a hybrid to a specified set of performance requirements and the prediction of fuel economy under a number of possible driving patterns (called driving cycles). Another provides an estimate of the incremental cost of the hybrid in comparison to a comparably performing conventional vehicle. In this paper, the models are applied to predict the NPV cost of conventional gasoline-fueled vehicles vs. parallel hybrid vehicles. The parallel hybrids are assumed to (1) be produced at high volume, (2) use nickel metal hydride battery packs, and (3) have high-strength steel bodies. The conventional vehicle also is assumed to have a high-strength steel body. The simulated vehicles are held constant in many respects, including 0-60 time, engine type, aerodynamic drag coefficient, tire …
Date: July 16, 1999
Creator: Santini, D. J. & Vyas, A. D.
System: The UNT Digital Library
Study of the high-j states in {sup 249}Cm. (open access)

Study of the high-j states in {sup 249}Cm.

The authors have performed the reaction {sup 248}Cm({sup 4}He, {sup 3}He) using 98.5-MeV alpha particles from the IUCF cyclotron to populate high-j states in {sup 249}Cm. A tentative assignment of the K{sub 17/2} component of the 1/2{sup +}[880] Nilsson state has been made.
Date: July 16, 1998
Creator: Ahmad, I.
System: The UNT Digital Library
Coherent multimoded dielectric wakefield accelerators. (open access)

Coherent multimoded dielectric wakefield accelerators.

There has recently been a study of the potential uses of multimode dielectric structures for wakefield acceleration [1]. This technique is based on adjusting the wakefield modes of the structure to constructively interfere at certain delays with respect to the drive bunch, thus providing an accelerating gradient enhancement over single mode devices. In this report we examine and attempt to clarify the issues raised by this work in the light of the present state of the art in wakefield acceleration.
Date: July 16, 1998
Creator: Power, J.
System: The UNT Digital Library
SRRC/ANL high current l-band single cell photocathode rf gun. (open access)

SRRC/ANL high current l-band single cell photocathode rf gun.

A high current L-band photocathode rf gun is under development at SRRC (Synchrotron Radiation Research Center, Taiwan) in collaboration with ANL (Argonne National Laboratory, USA). The goal is to produce up to 100 nC charge with the surface field gradient of over 90 MV/m at the center of the photocathode. In this report, they present the detailed design and initial test results. If successful, this gun will be used as the future AWA (Argonne Wakefield Accelerator)[1] high current gun.
Date: July 16, 1998
Creator: Ho, C. H.
System: The UNT Digital Library
A quasi-realtime x-ray microtomography system at the Advanced Photon Source. (open access)

A quasi-realtime x-ray microtomography system at the Advanced Photon Source.

The combination of high-brilliance x-ray sources, fast detector systems, wide-bandwidth networks, and parallel computers can substantially reduce the time required to acquire, reconstruct, and visualize high-resolution three-dimensional tomographic datasets. A quasi-realtime computed x-ray microtomography system has been implemented at the 2-BM beamline at the Advanced Photon Source at Argonne National Laboratory. With this system, a complete tomographic data set can be collected in about 15 minutes. Immediately after each projection is obtained, it is rapidly transferred to the Mathematics and Computing Sciences Division where preprocessing and reconstruction calculations are performed concurrently with the data acquisition by a SGI parallel computer. The reconstruction results, once completed, are transferred to a visualization computer that performs the volume rendering calculations. Rendered images of the reconstructed data are available for viewing back at the beamline experiment station minutes after the data acquisition was complete. The fully pipelined data acquisition and reconstruction system also gives us the option to acquire the tomographic data set in several cycles, initially with coarse then with fine angular steps. At present the projections are acquired with a straight-ray projection imaging scheme using 5-20 keV hard x rays in either phase or amplitude contrast mode at a 1-10 pm resolution. …
Date: July 16, 1999
Creator: DeCarlo, F.; Foster, I.; Insley, J.; Kesselman, C.; Lane, P.; Mancini, D. et al.
System: The UNT Digital Library
Design of a high charge (10 - 100 nC) and short pulse (2 - 5 ps) rf photocathode gun for wakefield acceleration. (open access)

Design of a high charge (10 - 100 nC) and short pulse (2 - 5 ps) rf photocathode gun for wakefield acceleration.

In this paper we present a design report on a 1-1/2 cell, L Band RF photocathode gun that is capable of generating and accelerating electron beams with peak currents >10 kA. We have performed simulation for bunch intensities in the range of 10-100 nC with peak axial electrical field at the photocathode of 30-100 MV/m. Unlike conventional short electron pulse generation, this design does not require magnetic pulse compression. Based on numerical simulations using SUPERFISH and PARMELA, this design will produce 20-100 nC beam at 18 MeV with rms bunch length 0.6-1.25 mm and normalized transverse emittance 30-108 mm mrad. Applications of this beam for wakefield acceleration is also discussed.
Date: July 16, 1998
Creator: Gai, W.
System: The UNT Digital Library
A novel laser doppler linear encoder using multiple-reflection optical design for high-resolution linear actuator. (open access)

A novel laser doppler linear encoder using multiple-reflection optical design for high-resolution linear actuator.

A novel laser Doppler linear encoder system (LDLE) has been developed at the Advanced Photon Source, Argonne National Laboratory. A self-aligning 3-D multiple-reflection optical design was used for the laser Doppler displacement meter (LDDM) to extend the encoder system resolution. The encoder is compact [about 70 mm(H) x 100 mm(W) x 250 mm(L)] and it has sub-Angstrom resolution, 100 mm/sec measuring speed, and 300 mm measuring range. Because the new device affords higher resolution, as compared with commercial laser interferometer systems, and yet cost less, it will have good potential for use in scientific and industrial applications.
Date: July 16, 1998
Creator: Shu, D.
System: The UNT Digital Library
Luminosity monitor. (open access)

Luminosity monitor.

Luminosity monitors are needed in each experiment doing spin physics at RHIC. They concentrate on the luminosity aspects here because, for example, with a 10{sup {minus}3} raw asymmetry in an experiment, an error of 10{sup {minus}4} in the luminosity is as significant as a 10% polarization error. Because luminosity is a property of how two beams overlap, the luminosity at an interaction region must be measured at that interaction region in order to be relevant to the experiment at that interaction region. The authors will have to do the physics and the luminosity measurements by using labels on the event sums according to the polarization labels on the colliding bunches. Most likely they will not have independent polarization measurement on each bunch, but only on all the filled bunches in a ring, or perhaps all the bunches that are actually used in an experiment. Most analyses can then be handled by using the nine combinations gotten from three kinds of bunches in each ring, +, {minus} and empty bunches. The empty bunches are needed to measure beam-gas background, (and some, like six in a row, are needed for the beam abort). Much of the difficulty comes from the fact that …
Date: July 16, 1998
Creator: Underwood, D. G.
System: The UNT Digital Library
Stress corrosion cracking behavior of irradiated model austenitic stainless steel alloys. (open access)

Stress corrosion cracking behavior of irradiated model austenitic stainless steel alloys.

Slow-strain-rate tensile tests (SSRTs) and posttest fractographic analyses by scanning electron microscopy were conducted on 16 austenitic stainless steel (SS) alloys that were irradiated at 289 C in He. After irradiation to {approx}0.3 x 10{sup 21} n{center_dot}cm{sup {minus}2} and {approx}0.9 x 10{sup 21} n{center_dot}cm{sup {minus}2} (E >1 MeV), significant heat-to-heat variations in the degree of intergranular and transgranular stress corrosion cracking (IGSCC and TGSCC) were observed. Following irradiation to a fluence of {approx}0.3 x 10{sup 21} n{center_dot}cm{sup {minus}2}, a high-purity laboratory heat of Type 316L SS (Si {approx} 0.024 wt%) exhibited the highest susceptibility to IGSCC. The other 15 alloys exhibited negligible susceptibility to IGSCC at this low fluence. The percentage of TGSCC on the fracture surfaces of SSRT specimens of the 16 alloys at {approx}0.3 x 10{sup 21} n{center_dot}cm{sup {minus}2} (E > 1 MeV) could be correlated well with N and Si concentrations; all alloys that contained <0.01 wt.% N and <1.0 wt. % Si were susceptible, whereas all alloys that contained >0.01 wt.% N or >1.0 wt.% Si were relatively resistant. High concentrations of Cr were beneficial. Alloys that contain <15.5 wt.% Cr exhibited greater percentages of TGSCC and IGSCC than those alloys with {approx}18 wt.% Cr, whereas …
Date: July 16, 1999
Creator: Chung, H. M.; Karlsen, T. M.; Ruther, W. E.; Shack, W. J. & Strain, R. V.
System: The UNT Digital Library
Assembly and maintenance of full scale NIF amplifiers in the amplifier module prototype laboratory (AMPLAB) (open access)

Assembly and maintenance of full scale NIF amplifiers in the amplifier module prototype laboratory (AMPLAB)

Mechanical assembly and maintenance of the prototype National Ignition Facility amplifiers in the Amplifier Module Prototype Laboratory (AMPLAB) at Lawrence Livermore National Laboratory requires specialized equipment designed to manipulate large and delicate amplifier components in a safe and clean manner. Observations made during the operation of this assembly and maintenance equipment in AMPLAB provide design guidance for similar tools being built for the National Ignition Facility. Fixtures used for amplifier frame installation, laser slab and flashlamp cassette assembly, transport, and installation, and in-situ blastshield exchange are presented. Examples include a vacuum slab gripper, slab handling clean crane, slab cassette assembly fixture, sealed transport vehicle for slab cassette movement between the cleanroom and amplifier, slab cassette transfer fixture between the cleanroom and transport vehicle, and equipment needed for frame assembly unit, blastshield, an d flashlamp cassette installation and removal. The use of these tools for amplifier assembly, system reconfiguration, reflector replacement, and recovery from an abnormal occurrence such as a flashlamp explosion is described. Observations are made on the design and operation of these tools and their contribution to the final design.
Date: July 16, 1998
Creator: Horvath, J. A.
System: The UNT Digital Library
Mirror-based fusion: some possible new directions (open access)

Mirror-based fusion: some possible new directions

This paper examines some possible areas for the study of new approaches to fusion research, ones that employ magnetic confinement systems based on open-ended field topology and employing the magnetic mirror principle. In the spirit of encouraging a wider look at possibilities, some unconventional approaches are suggested. These approaches, involving long linear systems having ion injectors and direct converters at their ends, attempt to exploit some inherent advantages of open-ended systems for fusion. The results of analysis, calculations and preliminary cost estimates for long linear systems of this type that utilize the magnetic mirror effect to achieve their operating regimes will be presented. The approaches suggested, when examined in greater depth, may not stand the test of time, but they might encourage thinking in new areas.
Date: July 16, 1998
Creator: Post, R F.
System: The UNT Digital Library
New prototype equation of state data library (open access)

New prototype equation of state data library

Equation of State (EOS) data is a necessary requirement for the simulation of many dynamic processes, including shock wave propagation, high velocity impact, laser-matter interaction, laser medicine, x-ray deposition and planetary and stellar interior evolution. Realistic simulations require high accuracy and smoothness in the EOS. In addition, some processes require independent ionic, electronic and radiation physics. In order to meet these needs, we have implemented a new EOS data library that is platform independent, hierarchically structured and easily extensible for future development. We have just begun our user testing phase and are considering future improvements.
Date: July 16, 1997
Creator: Corey, E. M. & Young, D. A.
System: The UNT Digital Library
Engineered Surety Using the Risk Equation (EnSURE) (open access)

Engineered Surety Using the Risk Equation (EnSURE)

Engineered Surety Using the Risk Equation (EnSURE) is a new approach being developed by Sandia National Laboratories for determining and mitigating risk. The EnSURE approach is based on the risk equation, which can be defined by the following equation: R = (Pa)(1-Pe)(C). Where R is risk, Pa is the likelihood of attack, Pe is the system effectiveness and C is the consequence. EnSURE considers each of the components of risk to help in assessing surety (e.g. security, safety, environmental) and providing for the most cost-effective ways to reduce risk. EnSURE is intended to help in evaluating and reducing the risk from either man-caused or natural events. It will help the decision-makers identify possible targets, evaluate the consequences of an event, assess the risk based on the threat and the existing conditions and then help in the application of mitigating measures. EnSURE is in the development stages. It builds on existing and ongoing development activities at Sandia, as well as the considerable work done in the fields of consequence analysis, risk analysis and intelligence. The components of EnSURE include consequences, constraints, threat, target/goal identification, facility/process characterization, evaluation and analysis, system improvement, and decision making. This paper provides a brief description of …
Date: July 16, 1998
Creator: Jaeger, C. D.; Paulus, W. K.; Duggan, R. A. & Miyoshi, D. S.
System: The UNT Digital Library
Equations for Gas Releasing Process From Pressurized Vessels in Odh Evaluation. (open access)

Equations for Gas Releasing Process From Pressurized Vessels in Odh Evaluation.

IN THE EVALUATION OF ODH, THE CALCULATION OF THE SPILL RATE FROM THE PRESSURIZED VESSEL IS THE CENTRAL TASK. THE ACCURACY OF THE ENGINEERING ESTIMATION BECOMES ONE OF THE SAFETY DESIGN ISSUES. THIS PAPER SUMMARIZES THE EQUATIONS FOR THE OXYGEN CONCENTRATION CALCULATION IN DIFFERENT CASES, AND DISCUSSES THE EQUATIONS FOR THE GAS RELEASE PROCESS CALCULATION BOTH FOR THE HIGH-PRESSURE GAS TANK AND THE LOW-TEMPERATURE LIQUID CONTAINER.
Date: July 16, 2001
Creator: Jia, L. X. & Wang, L.
System: The UNT Digital Library
Measurement of small radius gradient magnets using ion beams (open access)

Measurement of small radius gradient magnets using ion beams

Several small and precise 90{degree}, 20-inch-radius bending and focusing magnet systems will be needed for the transport line of the Fermilab Electron Cooling Project to transport 4.36 MeV electrons. Originally, it was anticipated that these magnets would have a gradient index of {minus}1/2. To measure these magnets and complete achromatic bend modules, a well defined beam transport system was developed to determine the transfer matrix knowing the position and angle of several input and output beam rays passing through the magnet. The beam for this was a 12.5 keV proton beam that has the same magnetic rigidity as the electron beam in the final setup. The magnetic field is approximately 300 Gauss. For this purpose a high-brightness proton source was used and the beam collimated to give a low emittance ({approximately}10{sup {minus}8} m rad) pencil beam of {approximately}1 mm diameter with a current of {approximately}100 nA. Details of the system and results of measuring a magnet will be presented.
Date: July 16, 2001
Creator: al., Charles W. Schmidt et
System: The UNT Digital Library
High-power testing of 11.424 GHz dielectric-loaded accelerating structures. (open access)

High-power testing of 11.424 GHz dielectric-loaded accelerating structures.

The design, construction, and bench testing of an X-band travelling-wave accelerating structure loaded with a permittivity=20 dielectric has been published recently by the Argonne Advanced Accelerator Group [1]. Here we describe a new program to build a test accelerator using this structure. The accelerator will be powered using high-power 11.424-GHz radiation available at the Magnicon Facility at the Naval Research Lab [2]. The magnicon is expected to provide up to 30 MW from each of two WR-90 output waveguide arms in pulses of up to 1-{micro}s duration, permitting tests of the dielectric-loaded X-band device at gradients of {approximately}40 MV/m. The use of higher power pulses (100-500 MW) eventually available at the output of an active pulse compressor [3] driven by the magnicon will permit gradients in excess of 100 MV/m to be achieved.
Date: July 16, 2001
Creator: Gold, S. H. & Gai, W.
System: The UNT Digital Library
SUSY searches at the Tevatron (open access)

SUSY searches at the Tevatron

D0 and CDF have already started collecting data from p{bar p} collisions at the Tevatron with the Main Injector in operation and at {radical}s {approx} 2 TeV. A number of recently completed SUSY searches using data from Run I are discussed.
Date: July 16, 2001
Creator: Spiropulu, M.
System: The UNT Digital Library
Recent results from CDF (open access)

Recent results from CDF

During the past year, the CDF Experiment has reported on a variety of results concerning QCD and electroweak studies, studies of the top quark, and searches for new phenomena. A sample of these results is presented here.
Date: July 16, 2001
Creator: Seidel, Sally Carol
System: The UNT Digital Library
RESPONSE TO THE CHALLENGES OF TECHNOLOGICAL CHANGE ON A SAFEGUARDS EQUIPMENT SUPPORT ORGANIZATION: DESIGN OF A PERFORMANCE-BASED TRAINING PROGRAM. (open access)

RESPONSE TO THE CHALLENGES OF TECHNOLOGICAL CHANGE ON A SAFEGUARDS EQUIPMENT SUPPORT ORGANIZATION: DESIGN OF A PERFORMANCE-BASED TRAINING PROGRAM.

None
Date: July 16, 2000
Creator: FARNITANO,M.; CARROLL,C.; STEIN,M. & SMILTNIEKS,V.
System: The UNT Digital Library
Field analysis of a dielectric-loaded rectangular waveguide accelerating structure. (open access)

Field analysis of a dielectric-loaded rectangular waveguide accelerating structure.

In this paper, we present a detailed analysis of the modes of a dielectric-loaded rectangular waveguide accelerating structure. In general, the acceleration field in a synchronous acceleration mode is non-uniform in the two transverse dimensions. However, we could use an array of these structures rotated alternatively by 90 degrees to get a focusing-defocusing force continuously as a simple FODO lattice, while maintaining uniform energy gain. The expressions of characteristic parameters such as R/Q, group velocity and attenuation constant are given. The longitudinal wake field experienced by a relativistic charged particle beam in the structure is also presented. These analytical results are also compared with numerical calculations using the MAFIA code suite demonstrating the validity of our analytic approach.
Date: July 16, 2001
Creator: Xiao, L.; Gai, W. & Sun, X.
System: The UNT Digital Library
Contributions to the Workshop on an e+e- collider in the VLHC tunnel (open access)

Contributions to the Workshop on an e+e- collider in the VLHC tunnel

This Workshop was extremely useful in fleshing out many of the details related to the VLLC. For example, at the workshop it became very clear that the large machine could not provide high luminosity polarized beams at both the Z0 pole and at high energy, and it would be best to provide the Z0 factory function in the injector. In addition, the workshop identified a number of topics for further R and D. A list of some of these topics follows: What is the lower limit on {beta}{sub y}* in the high energy collider? What is a reasonable upper limit on the beam-beam parameter at 183 GeV? Is there a way to coalesce electron bunches at high energy to finesse the TMCI current limit at injection, allowing a smaller beam pipe aperture to be used? Can feedback systems be useful to combat the TMCI instability at injection? In the 45 GeV Z{sup 0} factory, are two rings essential? Are wigglers essential for polarization in the Z{sup 0} factory? How can polarization at high energies be optimized? What is the optimum method of pumping the long vacuum chamber sections? How much cost and power minimization is possible in the complete design? …
Date: July 16, 2001
Creator: al., E Keil et
System: The UNT Digital Library
Effects of structural defects on the activation of sulfur donors in GaN/x/As/1-x/ formed by N implantation (open access)

Effects of structural defects on the activation of sulfur donors in GaN/x/As/1-x/ formed by N implantation

The effects of structural defects on the electrical activity of S doped GaN{sub x}As{sub 1-x} layers formed by S and N coimplantation in GaAs are reported. S and N ions were implanted to the depth of about 0.4 {micro}m. Electrochemical capacitance voltage measurements on samples annealed at 945 C for 10s show that in a thin (<0.1 {micro}m) surface layer the concentration of active shallow donors is almost an order of magnitude larger in S and N co-implanted samples than in samples implanted with S alone. The activation efficiency of S donors also shows a broad minimum at a depth of about 0.2 {micro}m below the surface. The results of these electrical measurements are correlated with the distribution of structural defects revealed by transmission electron microscopy (TEM). The TEM micrographs show that in addition to a band of dislocation loops commonly found in ion implanted GaAs, an additional band of small voids is observed in samples co-implanted with S and N. The location of this band correlates well with the region of reduced electrical activation of S donors, suggesting that formation of the voids through N accumulation results in a lower concentration of active, substitutional N atoms.
Date: July 16, 2001
Creator: Jasinski, J.; Yu, K.M.; Walukiewicz, W.; Liliental-Weber, Z. & Washburn, J.
System: The UNT Digital Library