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Fluctuation-Dissipation Theorem for Event-Dominated Processes (open access)

Fluctuation-Dissipation Theorem for Event-Dominated Processes

Article discussing the fluctuation-dissipation theorem for event-dominated processes.
Date: July 6, 2007
Creator: Allegrini, Paolo; Bologna, Mauro; Grigolini, Paolo & West, Bruce J.
System: The UNT Digital Library
Analytical solutions for a two-level system driven by a class of chirped pulses (open access)

Analytical solutions for a two-level system driven by a class of chirped pulses

Article on analytical solutions for a two-level system driven by a class of chirped pulses.
Date: July 6, 2010
Creator: Jha, Pankaj K. & Rostovtsev, Yuri V.
System: The UNT Digital Library
A self-adaptive burst-detection algorithm (open access)

A self-adaptive burst-detection algorithm

Article accompanying a poster presentation for the 2007 Computational Neuroscience Meeting. This article discusses a self-adaptive burst-detection algorithm.
Date: July 6, 2007
Creator: Tam, Nicoladie D.
System: The UNT Digital Library
A study of information flow in hospice interdisciplinary team meetings (open access)

A study of information flow in hospice interdisciplinary team meetings

Article on a study of information flow in hospice interdisciplinary team meetings.
Date: July 6, 2009
Creator: Demiris, George; Washington, Karla T.; Oliver, Debra Parker & Wittenberg-Lyles, Elaine
System: The UNT Digital Library
Identification of Candidate Genes Affecting ∆⁹-tetrahydrocannabinol Biosynthesis in Cannabis sativa (open access)

Identification of Candidate Genes Affecting ∆⁹-tetrahydrocannabinol Biosynthesis in Cannabis sativa

Article discussing the identification of candidate genes affecting ∆⁹-tetrahydrocannabinol biosynthesis in Cannabis sativa.
Date: July 6, 2009
Creator: Marks, M. David; Tian, Li; Wenger, Jonathan P.; Omburo, Stephanie N.; Soto-Fuentes, Wilfredo; He, Ji et al.
System: The UNT Digital Library
Lessons learned from U.S. Department of Defense 911-Bio Advanced Concept Technology Demonstrations. (open access)

Lessons learned from U.S. Department of Defense 911-Bio Advanced Concept Technology Demonstrations.

The US Department of Defense (DoD), in cooperation with other federal agencies, has taken many initiatives to improve its ability to support civilian response to a domestic biological terrorism incident. This paper discusses one initiative, the 911-Bio Advanced Concept Technology Demonstrations (ACTDs), conducted by the Office of the Secretary of Defense during 1997 to better understand: (1) the capability of newly developed chemical and biological collection and identification technologies in a field environment; (2) the ability of specialized DoD response teams to use these new technologies within the structure of cooperating DoD and civilian consequence management organizations; and (3) the adequacy of current modeling tools for predicting the dispersal of biological hazards. This paper discusses the experience of the ACTDs from the civilian community support perspective. The 911-Bio ACTD project provided a valuable opportunity for DoD and civilian officials to learn how they should use their combined capabilities to manage the aftermath of a domestic biological terrorism incident.
Date: July 6, 1999
Creator: Baldwin, T.; Gasper, W.; Lacher, L.; Newsom, D. & Yantosik, G.
System: The UNT Digital Library
Greenhouse-gas emissions from biofuel use in Asia. (open access)

Greenhouse-gas emissions from biofuel use in Asia.

Biomass is a primary fuel for much of the world's population. In some developing countries it can contribute 80-90% of total primary energy consumption. In Asia as a whole we estimate that biomass contributes about 22 EJ, almost 24% of total energy use. Much of this biomass is combusted in inefficient domestic stoves and cookers, enhancing the formation of products of incomplete combustion (PIC), many of which are greenhouse gases. An inventory of the combustion of biofuels (fuelwood, crop residues, and dried animal waste) in Asia is used to develop estimates of the emissions of carbon-containing greenhouse gases (CO{sub 2},CO, CH{sub 4}, and NMHC) in Asian countries. The data are examined from two perspectives: total carbon released and total global warming potential (GWP) of the gases. We estimate that blofuels contributed 573 Tg-C in 1990, about 28% of the total carbon emissions from energy use in Asia. China (259 Tg-C) and India (187 Tg-C) were the largest emitting countries by far. The majority of the emissions, 504 Tg-C, are in the form of CO{sub 2}; however, emissions of non-CO{sub 2} greenhouse gases are significant: 57 Tg-C as CO, 6.4 Tg-C as CH{sub 4}, and 5.9 Tg-C as NMHC. Because of …
Date: July 6, 1999
Creator: Streets, D. G. & Waldhoff, S. T.
System: The UNT Digital Library
MPC and A enhancements for the Murmansk shipping company icebreaker fleet (open access)

MPC and A enhancements for the Murmansk shipping company icebreaker fleet

The United States and the Russian Federation entered into a cooperative agreement in 1994 that resulted in a nuclear weapons non-proliferation program within the United States (US) Department of Energy (DOE) currently known as the Russia/Newly Independent States (NIS) Nuclear Material Security Task Force. In 1996, a project was initiated with the Murmansk Shipping Company to enhance material protection, control, and accounting of highly enriched nuclear fuel assemblies used for the Icebreaker Fleet. The commissioning ceremony for this project is scheduled for August 1999. This paper describes the physical protection, material control, and accounting measures implemented for the Icebreaker Fleet.
Date: July 6, 1999
Creator: Bartoch, O.; Bondarev, N.; Caskey, D.; Forehand, M.; Lambert, D.; Maltsev, V. et al.
System: The UNT Digital Library
Sodium beacon laser system for the Lick Observatory (open access)

Sodium beacon laser system for the Lick Observatory

The installation and performance characteristics of a 20 W sodium beacon laser system for the 3 m Shane telescope at the Lick Observatory are presented.
Date: July 6, 1995
Creator: Friedman, H.; Erbert, G. & Kuklo, T.
System: The UNT Digital Library
Estimates if population inversion for deep-UV transitions in Kr-like Y,Zr,Nb and Mo in a high-current reflex discharge (open access)

Estimates if population inversion for deep-UV transitions in Kr-like Y,Zr,Nb and Mo in a high-current reflex discharge

Kr-like ions are good candidates for FUV lasing since they can be produced in plasmas quite easily. We present results from a spectroscopic investigation of Y IV emission from a high current density, cold cathode reflex discharge. The Y II to Y V emission is recorded in the 200-3000 {angstrom} range using photometrically calibrated spectrometers, while the emission of trace aluminum ions serves for plasma diagnostics. The intensities of the Y IV 4d - 5p and 5s - 5p transitions strongly increase relative to lines from Y II and Y III with increasing plasma current. The spectra studied here are obtained at a current density of 1.75 A/cm{sup 2}. Experimental Y IV intensity ratios spanning several excited configurations are compared with collisional radiative predictions of the HULLAC atomic physics package. Good agreement is found for the measured and predicted ratios of 4p{sup 5}5p to 4p{sup 5}5s level populations per statistical weight. Finally, the response of the Kr-like system to a fast, transient excitation pulse is examined using the RADEX code. Large transient gains are predicted for several 5s - 5p transitions in Y IV, Zr V, Nb VI and Mo VII.
Date: July 6, 1999
Creator: Finkenthal, M.; May, M. J.; Fournier, K.; Goldstein, W. H.; Shlyaptsev, V. N.; Soukhanovskii, V. et al.
System: The UNT Digital Library
NIF optical specifications - the importance of the RMS gradient specification (open access)

NIF optical specifications - the importance of the RMS gradient specification

The performance of the National Ignition Facility (NIF), especially in terms of laser focusability, will be determined by several key factors. One of these key factors is the optical specification for the thousands of large aperture optics that will comprise the 192 beamlines. We have previously reported on the importance of the specification of the power spectral density (PSD) on NIF performance. Recently, we have been studying the importance of long spatial wavelength (>33 mm) phase errors on focusability. We have concluded that the preferred metric for determining the impact of these long spatial wavelength phase errors is the rms phase gradient. In this paper, we outline the overall approach to NIF optical specifications, detail the impact of the rms phase gradient on NIF focusability, discuss its trade-off with the PSD in determining the spot size and review measurements of optics similar to those to be manufactured for NIF.
Date: July 6, 1998
Creator: Auerbach, J. M.; Cotton, C. T.; English, R. E.; Henesian, M. A.; T, Hunt J.; Kelly, J. H. et al.
System: The UNT Digital Library
Design and performance of the ASAXS instrument at the Advanced Photon Source. (open access)

Design and performance of the ASAXS instrument at the Advanced Photon Source.

The SAXS instrument on the high brilliance undulator beam line (ID-12, BESSRC-CAT) at APS has been designed to produce high-resolution scattering patterns in the millisecond time domain. This instrument is equipped with a 20 cm x 20 cm position sensitive gas detector and a 15 cm x 15 cm high-resolution position sensitive CCD mosaic detector. A photodiode detector mounted on a 3 mm diameter beam stop permits quick alignment of the instrument as well as precise measurement of the transmitted beam intensity. The ease of changing the sample to detector distance and tuning of x-ray energy enables easy access to different Q ranges. With this instrument we routinely measure data in a Q range of 0.001 to 1 {angstrom}{sup {minus}1}. The exposure time with the CCD detector varies from 0.1 second to 10 sec depending on the scattering cross-section of the samples. Techniques to interface ancillary equipment for time-resolved studies and software for faster online analysis of the data have also been developed. We have obtained excellent data on the unfolding of proteins in the millisecond time domain, ASAXS of metallic alloys by using this instrument.
Date: July 6, 1999
Creator: Seifert, S.; Thiyagarajan, P.; Tiede, D. M. & Winans, R. E.
System: The UNT Digital Library
Optical determination of incipient soot particle concentrations in ethene laminar diffusion flames. (open access)

Optical determination of incipient soot particle concentrations in ethene laminar diffusion flames.

Recent studies in premixed flames have shown the existence of ''transparent particles.'' These particles, 2 nm in size and in high number densities are considered to be a phase transitional between the gas phase PAH species and particulate soot. In the present study, various optical diagnostics were evaluated for measuring the concentration of these particles in situ, Through such evaluations, a technique using extinction at two wavelengths was found to be ideal. While employing such a technique, the volume fractions of these particles in an ethene laminar diffusion flame were measured. Low in the flame, these particles were found to be concentrated in the fuel rich core, while at higher locations, they could be found with appreciable volume fractions even in the soot laden regions. Having given due consideration for the errors due to uncertainties in the optical constants, we report the existence of these particles in an ethene flame with volume fractions comparable to those of soot. Also, similar measurements performed in a low sooting ethene/methanol flame show the concentration of these particles to be of the same order of magnitude as in a pure ethene flame.
Date: July 6, 1999
Creator: Gupta, S. B. & Santoro, R. J.
System: The UNT Digital Library
Frequency response characteristics and response spectra of base-isolated and un-isolated structures (open access)

Frequency response characteristics and response spectra of base-isolated and un-isolated structures

The transmissibility of seismic loads through a linear base-isolation system is analyzed using an impedance method. The results show that the system acts like a {open_quotes}low-pass{close_quotes} filter. It attenuates high-frequency loads but passes through low-frequency ones. The filtering effect depends on the vibration frequencies and damping of the isolated structure and the isolation system. This paper demonstrates the benefits and design principles of base isolation by comparing the transmissibilities and response spectra of isolated and un-isolated structures. Parameters of typical isolated buildings and ground motions of the 1994 Northridge earthquake are used for the demonstration.
Date: July 6, 1995
Creator: Mok, G.C. & Namba, H.
System: The UNT Digital Library
Is there a need for site productivity functions for short-rotation woody crop plantings? (open access)

Is there a need for site productivity functions for short-rotation woody crop plantings?

For over a decade, researchers have used small-scale research plots to assist development and selection of high yielding, pest-resistant clones of fast-growing hardwoods such as hybrid poplar (Populus spp.). Substantial advances have been made in the techniques and criteria for screening species and selecting clones. Data from these research plots indicate that the ultimate performance of selected clones is dependent upon variable factors in the environment. Until now, researchers could only determine the suitability of a given site for such clones, not the actual yield potential of the site. Recently in the north central US, several clones were planted on larger-than-research-scale plots on private land recontracted under the Conservation Reserve Program (CRP). The historical database could not provide a framework which would allow producers to predict the yield potential of a particular clone on a specific site. Through a systematic combination of clonal trials on experimental research-scale plots and operational plantings on 50 to 100 acre agricultural-scale field plots, it may be possible to develop yield functions or site quality equations which would predict biomass yields at rotation for selected clones. Such estimates will (1) reduce the probability of planting failure, (2) allow maximum expression of the genetic potential of …
Date: July 6, 1995
Creator: Downing, M. & Tuskan, G.A.
System: The UNT Digital Library
Exploring the Role of Shear Stress and Severe Turbulence in Downstream Fish Passage (open access)

Exploring the Role of Shear Stress and Severe Turbulence in Downstream Fish Passage

Fish may be exposed to damaging levels of fluid shear stress and turbulence while passing through hydroelectric power plants. The generally assumed locations for such potential damage are the turbine and draft tube passages, although it is possible that fish are also injured during passage over the spillway or through sluiceways and fish bypass outfalls. Unless mitigated, fluid-induced injuries and mortality could frustrate efforts to develop advanced, fish-friendly turbines or to provide safe alternate downstream passages. The effects of shear stress and turbulence on fish are poorly understood, in part because of the difficulties in conceptualizing these phenomena, determining their magnitudes and distribution within hydroelectric systems, and then recreating them in a controlled laboratory environment. We define the fluid phenomena that are relevant to the assessment of effects on fish. The magnitudes of fluid stresses associated with man-altered aquatic environments are often considerably higher than those found in natural environments (e.g., normal river flows). However, levels of shear stresses that occur during flash floods appear to be comparable to those expected within a turbine. Past studies of the effects of shear stress on fish are of limited value, mainly because of their narrow scope and lack of instrumentation to measure …
Date: July 6, 1999
Creator: Cada, G.; Carlson, T.; Ferguson, J.; Richmond, M. & Sale, M.
System: The UNT Digital Library
Error analysis for fast scintillator-based ICF burn history measurements (open access)

Error analysis for fast scintillator-based ICF burn history measurements

Plastic scintillator material acts as a neutron-to-light converter in instruments that make ICF burn history measurements. Light output for a detected neutron has a fast rise time (420 ps) and a relatively long decay constant (1.2 ns). For a burst of neutrons whose duration is much shorter than the decay constant, instantaneous light output is approximately proportional to the integral of the neutron interaction rate with the scintillator material. Burn history is obtained by deconvolving the exponential decay from the recorded signal.
Date: July 6, 1998
Creator: Lerche, R A & Ognibene, T J
System: The UNT Digital Library
Preliminary results for two pion resonances in D{sup +} and D{sup +}{sub s} {r_arrow} {pi}{sup {minus}}{pi}{sup +}{pi}{sup +} from Fermilab experiment E-791 (open access)

Preliminary results for two pion resonances in D{sup +} and D{sup +}{sub s} {r_arrow} {pi}{sup {minus}}{pi}{sup +}{pi}{sup +} from Fermilab experiment E-791

In this paper the authors present preliminary results of a coherent amplitude analysis of three-pion decays of charm mesons. The analysis includes a greater number of possible resonant states than in previous analyses, and produces masses and Breit-Wigner widths of the isoscalar resonances f{sub 0} (980) and f{sub 0} (1370) with better precision than previous measurements. They also present preliminary results for the mass and width of the low lying f{sub o} (400), sometimes called the {sigma} meson.
Date: July 6, 2000
Creator: Stefanski, Raymond J.
System: The UNT Digital Library
The evolution of ANL CMT gloveboxes (open access)

The evolution of ANL CMT gloveboxes

This report summarizes the following topics: the design approach based upon user-friendly concepts; utilization of existing component designs; cost effectiveness; schedule; and adaptable to project process changes without losing overall effectiveness of user-friendly approach.
Date: July 6, 2000
Creator: Malecha, R. F.; Frigo, A. A. & Preuss, D. E.
System: The UNT Digital Library
Stella Experiment: Hardware Issues (open access)

Stella Experiment: Hardware Issues

The Staged Electron Laser Acceleration (STELLA) experiment is currently being assembled and tested at the BNL Accelerator Test Facility (ATF). The existing BNL inverse free electron laser (IFEL) has been positioned upstream of the inverse Cerenkov acceleration (ICA) experiment on Beamline {number_sign}1. This beamline also features new quadrupoles and a new spectrometer capable of a {+-}20% energy acceptance. A new laser beam transport system has been installed to permit accurate control of the laser phase for the laser beams sent to the IFEL and ICA devices. Detection of the microbunches are performed using a coherent transition radiation (CTR) diagnostic similar to one already demonstrated at the ATF.
Date: July 6, 1998
Creator: Kusche, K. P.; Campbell, L. P.; Gottschalk, S. C.; Kimura, W. D.; Quimby, D. C.; Robinson, K. E. et al.
System: The UNT Digital Library
A Framework for Regulatory Requirements and Industry Standards for New Nuclear Power Plants (open access)

A Framework for Regulatory Requirements and Industry Standards for New Nuclear Power Plants

None
Date: July 6, 2000
Creator: Duran, Felicia A.; Camp, Allen L.; Apostolakis, George & Golay, Michael
System: The UNT Digital Library
Weapon Storage Technology Demonstration Facility (open access)

Weapon Storage Technology Demonstration Facility

None
Date: July 6, 2000
Creator: Mann, Greg A.; Sviridov, A. & Zimovets, K.
System: The UNT Digital Library
High Amplitude Secondary Mass Drive (open access)

High Amplitude Secondary Mass Drive

In this paper we describe a high amplitude electrostatic drive for surface micromachined mechanical oscillators that may be suitable for vibratory gyroscopes. It is an advanced design of a previously reported dual mass oscillator (Dyck, et. al., 1999). The structure is a 2 degree-of-freedom, parallel-plate driven motion amplifier, termed the secondary mass drive oscillator (SMD oscillator). During each cycle the device contacts the drive plates, generating large electrostatic forces. Peak-to-peak amplitudes of 54 {micro}m have been obtained by operating the structure in air with an applied voltage of 11 V. We describe the structure, present the analysis and design equations, and show recent results that have been obtained, including frequency response data, power dissipation, and out-of- plane motion.
Date: July 6, 2000
Creator: DYCK,CHRISTOPHER WILLIAM; ALLEN,JAMES J.; HUBER,ROBERT JOHN & SNIEGOWSKI,JEFFRY J.
System: The UNT Digital Library
Perspectives on Low Power and Shutdown Risk (open access)

Perspectives on Low Power and Shutdown Risk

This paper presents results from a program sponsored by the US Nuclear Regulatory Commission to examine the risks from low power and shutdown operations. Significant progress has been made by the industry in reducing such risks; however, important operational events continue to occur. Current perceptions of low power and shutdown risks are discussed in the paper along with an assessment of the current methods for understanding important events and quantifying their associated risk.
Date: July 6, 2000
Creator: Camp, Allen L.; Whitehead, Donnie W.; Wheeler, Timothy A.; Lehner, John; Chu, Tsong-Lun; Lois, Erasmai et al.
System: The UNT Digital Library