AXAF-1 high-resolution mirror assembly image model and comparison with x-ray ground-test image
NASA Astrophysics Data System (ADS)
Zissa, David E.
1999-09-01
The completed High Resolution Mirror Assembly (HRMA) of the Advanced X-ray Astrophysics Facility - Imaging (AXAF-I) was tested at the X-ray Calibration Facility (XRCF) at the NASA- Marshall Space Flight Center (MSFC) in 1997. The MSFC image model was developed during the development of AXAF-I. The MSFC model is a detailed ray-trace model of the as-built HRMA optics and the XRCF teste conditions. The image encircled-energy distributions from the model are found to general agree well with XRCF test data nd the preliminary Smithsonian Astrophysical Observatory (SAO) model. MSFC model effective-area result generally agree with those of the preliminary SAO model. Preliminary model effective-area results were reported by SAO to be approximately 5-13 percent above initial XRCF test results. The XRCF test conditions are removed from the MSFC ray-trace model to derive an on-orbit prediction of the HRMA image.
[Diagnostic rationalism. Views of general practitioners on fibromyalgia].
Daehli, B
1993-09-20
Clinical practice is characterized by having to make numerous important decisions, including the diagnosis. In this study, general practitioners were asked to agree or to disagree with statements of fibromyalgia. The main purpose was to test the usefulness of two well-known models for decision-making when studying diagnosis in cases of uncertainty and scepticism. The results show that the models are inadequate to explain the decisions.
WHEN HAS A MODEL BEEN SUFFICIENTLY CALIBRATED AND TESTED TO BE PUT TO EFFICIENT USE?
The question of what degree of predictive error is acceptable for environmental models is explored. Two schools of thought are presented. The universalist school would argue that it is possible to agree on general acceptance criteria for specific categories of models, particula...
A Generalized Quantum-Inspired Decision Making Model for Intelligent Agent
Loo, Chu Kiong
2014-01-01
A novel decision making for intelligent agent using quantum-inspired approach is proposed. A formal, generalized solution to the problem is given. Mathematically, the proposed model is capable of modeling higher dimensional decision problems than previous researches. Four experiments are conducted, and both empirical experiments results and proposed model's experiment results are given for each experiment. Experiments showed that the results of proposed model agree with empirical results perfectly. The proposed model provides a new direction for researcher to resolve cognitive basis in designing intelligent agent. PMID:24778580
NASA Astrophysics Data System (ADS)
Griessbach, Sabine; Hoffmann, Lars; Höpfner, Michael; Riese, Martin; Spang, Reinhold
2013-09-01
The viability of a spectrally averaging model to perform radiative transfer calculations in the infrared including scattering by atmospheric particles is examined for the application of infrared limb remote sensing measurements. Here we focus on the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) aboard the European Space Agency's Envisat. Various spectra for clear air and cloudy conditions were simulated with a spectrally averaging radiative transfer model and a line-by-line radiative transfer model for three atmospheric window regions (825-830, 946-951, 1224-1228 cm-1) and compared to each other. The results are rated in terms of the MIPAS noise equivalent spectral radiance (NESR). The clear air simulations generally agree within one NESR. The cloud simulations neglecting the scattering source term agree within two NESR. The differences between the cloud simulations including the scattering source term are generally below three and always below four NESR. We conclude that the spectrally averaging approach is well suited for fast and accurate infrared radiative transfer simulations including scattering by clouds. We found that the main source for the differences between the cloud simulations of both models is the cloud edge sampling. Furthermore we reasoned that this model comparison for clouds is also valid for atmospheric aerosol in general.
Haushild, W.L.; Prych, Edmund A.
1976-01-01
Total- and fecal-coliform bacteria, plus pH, alkalinity, and dissolved inorganic carbon are water-quality parameters that have been added to an existing numerical model of water quality in the salt-wedge reach of the Duwamish River estuary in Washington. The coliform bacteria are modeled using a first-order decay (death) rate, which is a function of the local salinity, temperature, and daily solar radiation. The pH is computed by solving a set of chemical-equilibrium equations for carbonate-bicarbonate buffered aqueous solutions. Concentrations of total- and fecal-coliform bacteria computed by the model for the Duwamish River estuary during June-September 1971 generally agreed with observed concentrations within about 40 and 60 percent, respectively. The computed pH generally agreed with observed pH within about a 0.2 pH unit; however, for one 3-week period the computed pH was about a 0.4 unit lower than the observed pH. (Woodard-USGS)
ERIC Educational Resources Information Center
Roberts, James S.; Laughlin, James E.
1996-01-01
A parametric item response theory model for unfolding binary or graded responses is developed. The graded unfolding model (GUM) is a generalization of the hyperbolic cosine model for binary data of D. Andrich and G. Luo (1993). Applicability of the GUM to attitude testing is illustrated with real data. (SLD)
Electromagnetic axial anomaly in a generalized linear sigma model
NASA Astrophysics Data System (ADS)
Fariborz, Amir H.; Jora, Renata
2017-06-01
We construct the electromagnetic anomaly effective term for a generalized linear sigma model with two chiral nonets, one with a quark-antiquark structure, the other one with a four-quark content. We compute in the leading order of this framework the decays into two photons of six pseudoscalars: π0(137 ), π0(1300 ), η (547 ), η (958 ), η (1295 ) and η (1760 ). Our results agree well with the available experimental data.
10Be measured in a GRIP snow pit and modeled using the ECHAM5-HAM general circulation model
NASA Astrophysics Data System (ADS)
Heikkilä, U.; Beer, J.; Jouzel, J.; Feichter, J.; Kubik, P.
2008-03-01
10Be measured in a Greenland Ice Core Project (GRIP) snow pit (1986-1990) with a seasonal resolution is compared with the ECHAM5-HAM GCM run. The mean modeled 10Be concentration in ice (1.0.104 atoms/g) agrees well with the measured value (1.2.104 atoms/g). The measured 10Be deposition flux (88 atoms/m2/s) also agrees well with the modeled flux (69 atoms/m2/s) and the measured precipitation rate (0.67 mm/day) agrees with the modeled rate (0.61 mm/day). The mean surface temperature of -31°C estimated from δ 18O is lower than the temperature measured at a near-by weather station (-29°C) and the modeled temperature (-26°C). During the 5-year period the concentrations and deposition fluxes, both measured and modeled, show a decreasing trend consistent with the increase in the solar activity. The variability of the measured and modeled concentrations and deposition fluxes is very similar suggesting that the variability is linked to a variability in production rather than the local meteorology.
Comparison of Einstein-Boltzmann solvers for testing general relativity
NASA Astrophysics Data System (ADS)
Bellini, E.; Barreira, A.; Frusciante, N.; Hu, B.; Peirone, S.; Raveri, M.; Zumalacárregui, M.; Avilez-Lopez, A.; Ballardini, M.; Battye, R. A.; Bolliet, B.; Calabrese, E.; Dirian, Y.; Ferreira, P. G.; Finelli, F.; Huang, Z.; Ivanov, M. M.; Lesgourgues, J.; Li, B.; Lima, N. A.; Pace, F.; Paoletti, D.; Sawicki, I.; Silvestri, A.; Skordis, C.; Umiltà, C.; Vernizzi, F.
2018-01-01
We compare Einstein-Boltzmann solvers that include modifications to general relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes that primarily model general scalar-tensor theories, three codes that model Jordan-Brans-Dicke (JBD) gravity, a code that models f (R ) gravity, a code that models covariant Galileons, a code that models Hořava-Lifschitz gravity, and two codes that model nonlocal models of gravity. Comparing predictions of the angular power spectrum of the cosmic microwave background and the power spectrum of dark matter for a suite of different models, we find agreement at the subpercent level. This means that this suite of Einstein-Boltzmann solvers is now sufficiently accurate for precision constraints on cosmological and gravitational parameters.
Modeling Enclosure Design in Above-Grade Walls
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lstiburek, J.; Ueno, K.; Musunuru, S.
2016-03-01
Building Science Corporation modeled typically well-performing wall assemblies using Wärme und Feuchte instationär (WUFI) Version 5.3 software and demonstrated that these models agree with historic experience when calibrated and modeled correctly. This technical report provides a library of WUFI modeling input data and results. Within the limits of existing experience, this information can be generalized for applications to a broad population of houses.
NASA Technical Reports Server (NTRS)
Lemaster, E. W.
1975-01-01
The experimental bidirectional reflectance of cotton is presented and compared to the Suits vegetation model. Some wheat reflectance data are presented for a Mexican dwarf wheat. The general results are that the exchange of source position and detector position gives the same reflectance measurement if the irradiance is purely specular. This agrees with Suites. The reflectance versus sun angle and reflectance versus detector angle do not agree with the Suits predictions. There is qualitative agreement between the Suits model and reflectance versus wavelength, but quantitative agreement has not been observed. Reflectance of a vegetation canopy with detector azimuth shows a change of 10 to 40% for even sun angles near zenith, so it seems advisable to include azimuthal angles into models of vegetation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sasakura, Naoki
The tensor model is discussed as theory of dynamical fuzzy spaces in order to formulate gravity on fuzzy spaces. The numerical analyses of the tensor models possessing Gaussian background solutions have shown that the low-lying long-wavelength fluctuations around the backgrounds are in remarkable agreement with the geometric fluctuations on flat spaces in the general relativity. It has also been shown that part of the orthogonal symmetry of the tensor model spontaneously broken by the backgrounds agrees with the local translation symmetry of the general relativity. Thus the tensor model provides an interesting model of simultaneous emergence of space, the generalmore » relativity, and its local translation symmetry.« less
Gravitational redshift of galaxies in clusters as predicted by general relativity.
Wojtak, Radosław; Hansen, Steen H; Hjorth, Jens
2011-09-28
The theoretical framework of cosmology is mainly defined by gravity, of which general relativity is the current model. Recent tests of general relativity within the Lambda Cold Dark Matter (ΛCDM) model have found a concordance between predictions and the observations of the growth rate and clustering of the cosmic web. General relativity has not hitherto been tested on cosmological scales independently of the assumptions of the ΛCDM model. Here we report an observation of the gravitational redshift of light coming from galaxies in clusters at the 99 per cent confidence level, based on archival data. Our measurement agrees with the predictions of general relativity and its modification created to explain cosmic acceleration without the need for dark energy (the f(R) theory), but is inconsistent with alternative models designed to avoid the presence of dark matter. © 2011 Macmillan Publishers Limited. All rights reserved
Generalization of a model of hysteresis for dynamical systems.
Piquette, Jean C; McLaughlin, Elizabeth A; Ren, Wei; Mukherjee, Binu K
2002-06-01
A previously described model of hysteresis [J. C. Piquette and S. E. Forsythe, J. Acoust. Soc. Am. 106, 3317-3327 (1999); 106, 3328-3334 (1999)] is generalized to apply to a dynamical system. The original model produces theoretical hysteresis loops that agree well with laboratory measurements acquired under quasi-static conditions. The loops are produced using three-dimensional rotation matrices. An iterative procedure, which allows the model to be applied to a dynamical system, is introduced here. It is shown that, unlike the quasi-static case, self-crossing of the loops is a realistic possibility when inertia and viscous friction are taken into account.
Generalized IRT Models for Extreme Response Style
ERIC Educational Resources Information Center
Jin, Kuan-Yu; Wang, Wen-Chung
2014-01-01
Extreme response style (ERS) is a systematic tendency for a person to endorse extreme options (e.g., strongly disagree, strongly agree) on Likert-type or rating-scale items. In this study, we develop a new class of item response theory (IRT) models to account for ERS so that the target latent trait is free from the response style and the tendency…
A bioenergetic model for zebrafish Danio rerio (Hamilton)
Chizinski, C.J.; Sharma, Bibek; Pope, K.L.; Patino, R.
2008-01-01
A bioenergetics model was developed from observed consumption, respiration and growth rates for zebrafish Danio rerio across a range (18-32?? C) of water temperatures, and evaluated with a 50 day laboratory trial at 28?? C. No significant bias in variable estimates was found during the validation trial; namely, predicted zebrafish mass generally agreed with observed mass. ?? 2008 The Authors.
An ice-ocean coupled model for the Northern Hemisphere
NASA Technical Reports Server (NTRS)
Cheng, Abe; Preller, Ruth
1992-01-01
The Hibler ice model has been modified and adapted to a domain that includes most of the sea ice-covered areas in the Northern Hemisphere. This model, joined with the Cox ocean model, is developed as an enhancement to the U.S. Navy's sea ice forecasting, PIPS, and is termed PIPS2.0. Generally, the modeled ice edge is consistent with the Navy-NOAA Joint Ice Center weekly analysis, and the modeled ice thickness distribution agrees with submarine sonar data in the central Arctic basin.
A General Model of Organizational Values in Educational Administration
ERIC Educational Resources Information Center
Mueller, Robin Alison
2014-01-01
Values theorists in educational administration agree that understanding organizational values is integral to organizational effectiveness. However, research in this area tends to be superficial, and a review of pertinent literature reveals no clear definition of organizational values or consequent implications for practical application. One of the…
The polarization of continuum radiation in sunspots. I - Rayleigh and Thomson scattering
NASA Technical Reports Server (NTRS)
Finn, G. D.; Jefferies, J. T.
1974-01-01
Expressions are derived for the Stokes parameters of light scattered by a layer of free electrons and hydrogen atoms in a sunspot. A physically reasonable sunspot model was found so that the direction of the calculated linear polarization agrees reasonably with observations. The magnitude of the calculated values of the linear polarization agrees generally with values observed in the continuum at 5830 A. Circular polarization in the continuum also accompanies electron scattering in spot regions; however for commonly accepted values of the longitudinal magnetic field, the predicted circular polarization is much smaller than observed.
Simulation of the potentiodynamic and galvanostatic phase formation in melts
NASA Astrophysics Data System (ADS)
Isaev, V. A.; Grishenkova, O. V.; Kosov, A. V.; Semerikova, O. L.; Zaykov, Yu. P.
2017-02-01
A general scheme is used to consider the initial stages of electrocrystallization under potentiodynamic and galvanostatic conditions. Proposed theoretical models are shown to agree well with the experimental results obtained during the electrodeposition of silver crystals on an iridium microelectrode from nitrate melt containing an excess background electrolyte.
Arctic Ocean Freshwater: How Robust are Model Simulations
NASA Technical Reports Server (NTRS)
Jahn, A.; Aksenov, Y.; deCuevas, B. A.; deSteur, L.; Haekkinen, S.; Hansen, E.; Herbaut, C.; Houssais, M.-N.; Karcher, M.; Kauker, F.;
2012-01-01
The Arctic freshwater (FW) has been the focus of many modeling studies, due to the potential impact of Arctic FW on the deep water formation in the North Atlantic. A comparison of the hindcasts from ten ocean-sea ice models shows that the simulation of the Arctic FW budget is quite different in the investigated models. While they agree on the general sink and source terms of the Arctic FW budget, the long-term means as well as the variability of the FW export vary among models. The best model-to-model agreement is found for the interannual and seasonal variability of the solid FW export and the solid FW storage, which also agree well with observations. For the interannual and seasonal variability of the liquid FW export, the agreement among models is better for the Canadian Arctic Archipelago (CAA) than for Fram Strait. The reason for this is that models are more consistent in simulating volume flux anomalies than salinity anomalies and volume-flux anomalies dominate the liquid FW export variability in the CAA but not in Fram Strait. The seasonal cycle of the liquid FW export generally shows a better agreement among models than the interannual variability, and compared to observations the models capture the seasonality of the liquid FW export rather well. In order to improve future simulations of the Arctic FW budget, the simulation of the salinity field needs to be improved, so that model results on the variability of the liquid FW export and storage become more robust.
Napolitano, Lena M; Savarise, Mark; Paramo, Juan C; Soot, Laurel C; Todd, S Rob; Gregory, Jay; Timmerman, Gary L; Cioffi, William G; Davis, Elisabeth; Sachdeva, Ajit K
2014-05-01
General surgery residency training has changed with adoption of the 80-hour work week, patient expectations, and the malpractice environment, resulting in decreased resident autonomy during the chief resident year. There is considerable concern that graduating residents are not prepared for independent surgical practice. Two online surveys were developed, one for "young surgeons" (American College of Surgeons [ACS] Fellows 45 years of age and younger) and one for "older surgeons" (ACS Fellows older than 45 years of age). The surveys were distributed by email to 2,939 young and 9,800 older surgeons. The last question was open-ended with a request to provide comments. A qualitative and quantitative analysis of all comments was performed. The response rate was 9.6% (282 of 2,939) of young and 10% (978 of 9,800) of older surgeons. The majority of young surgeons (94% [58.7% strongly agree, 34.9% agree]) stated they had adequate surgical training and were prepared for transition to the surgery attending role (91% [49.6% strongly agree, 41.1% agree]). In contrast, considerably fewer older surgeons believed that there was adequate surgical training (59% [18.7% strongly agree, 40.2% agree]) or adequate preparation for transition to the surgery attending role (53% [16.93% strongly agree, 36.13% agree]). The 2 groups' responses were significantly different, chi-square test of association (3) = 15.73, p = 0.0012. Older surgeons focused considerably more on residency issues (60% vs 42%, respectively), and young surgeons focused considerably more on business and practice issues (30% vs 14%, respectively). Young and older surgeons' perceptions of general surgery residents' readiness to practice independently after completion of general surgery residency differ significantly. Future work should focus on determination of specific efforts to improve the transition to independent surgery practice for the general surgery resident. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.
Hadron-nucleus interactions at high energies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chiu, C.B.; He, Z.; Tow, D.M.
1982-06-01
A simple space-time description of high-energy hadron-nucleus interactions is presented. The model is based on the DTU (dual topologial unitarization)-parton-model description of soft multiparticle production in hadron-hadron interactions. The essentially parameter-free model agrees well with the general features of high-energy data for hadron-nucleus interactions; in particular, this DTU-parton model has a natural explanation for an approximate nu-bar universality. The expansion to high-energy nucleus-nucleus interactions is presented. We also compare and contrast this model with several previously proposed models.
Hadron-nucleus interactions at high energies
NASA Astrophysics Data System (ADS)
Chiu, Charles B.; He, Zuoxiu; Tow, Don M.
1982-06-01
A simple space-time description of high-energy hadron-nucleus interactions is presented. The model is based on the DTU (dual topological unitarization) -parton-model description of soft multiparticle production in hadron-hadron interactions. The essentially parameter-free model agrees well with the general features of high-energy data for hadron-nucleus interactions; in particular, this DTU-parton model has a natural explanation for an approximate ν¯ universality. The extension to high-energy nucleus-nucleus interactions is presented. We also compare and contrast this model with several previously proposed models.
NASA Technical Reports Server (NTRS)
Rumsey, C. L.
2009-01-01
The ability of kappa-omega models to predict compressible turbulent skin friction in hypersonic boundary layers is investigated. Although uncorrected two-equation models can agree well with correlations for hot-wall cases, they tend to perform progressively worse - particularly for cold walls - as the Mach number is increased in the hypersonic regime. Simple algebraic models such as Baldwin-Lomax perform better compared to experiments and correlations in these circumstances. Many of the compressibility corrections described in the literature are summarized here. These include corrections that have only a small influence for kappa-omega models, or that apply only in specific circumstances. The most widely-used general corrections were designed for use with jet or mixing-layer free shear flows. A less well-known dilatation-dissipation correction intended for boundary layer flows is also tested, and is shown to agree reasonably well with the Baldwin-Lomax model at cold-wall conditions. It exhibits a less dramatic influence than the free shear type of correction. There is clearly a need for improved understanding and better overall physical modeling for turbulence models applied to hypersonic boundary layer flows.
Connections between the Sznajd model with general confidence rules and graph theory
NASA Astrophysics Data System (ADS)
Timpanaro, André M.; Prado, Carmen P. C.
2012-10-01
The Sznajd model is a sociophysics model that is used to model opinion propagation and consensus formation in societies. Its main feature is that its rules favor bigger groups of agreeing people. In a previous work, we generalized the bounded confidence rule in order to model biases and prejudices in discrete opinion models. In that work, we applied this modification to the Sznajd model and presented some preliminary results. The present work extends what we did in that paper. We present results linking many of the properties of the mean-field fixed points, with only a few qualitative aspects of the confidence rule (the biases and prejudices modeled), finding an interesting connection with graph theory problems. More precisely, we link the existence of fixed points with the notion of strongly connected graphs and the stability of fixed points with the problem of finding the maximal independent sets of a graph. We state these results and present comparisons between the mean field and simulations in Barabási-Albert networks, followed by the main mathematical ideas and appendices with the rigorous proofs of our claims and some graph theory concepts, together with examples. We also show that there is no qualitative difference in the mean-field results if we require that a group of size q>2, instead of a pair, of agreeing agents be formed before they attempt to convince other sites (for the mean field, this would coincide with the q-voter model).
Generalized Einstein relation for the mutual diffusion coefficient of a binary fluid mixture.
Felderhof, B U
2017-08-21
The method employed by Einstein to derive his famous relation between the diffusion coefficient and the friction coefficient of a Brownian particle is used to derive a generalized Einstein relation for the mutual diffusion coefficient of a binary fluid mixture. The expression is compared with the one derived by de Groot and Mazur from irreversible thermodynamics and later by Batchelor for a Brownian suspension. A different result was derived by several other workers in irreversible thermodynamics. For a nearly incompressible solution, the generalized Einstein relation agrees with the expression derived by de Groot and Mazur. The two expressions also agree to first order in solute density. For a Brownian suspension, the result derived from the generalized Smoluchowski equation agrees with both expressions.
75 FR 43105 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-23
... beams and the rear pressurized bulkhead. If left uncorrected, long term fatigue stress could locally... term fatigue stress could locally weaken the structure, compromising the fuselage structural integrity... reviewed the MCAI and related service information and, in general, agree with their substance. But we might...
Subdiffusion kinetics of nanoprecipitate growth and destruction in solid solutions
NASA Astrophysics Data System (ADS)
Sibatov, R. T.; Svetukhin, V. V.
2015-06-01
Based on fractional differential generalizations of the Ham and Aaron-Kotler precipitation models, we study the kinetics of subdiffusion-limited growth and dissolution of new-phase precipitates. We obtain the time dependence of the number of impurities and dimensions of new-phase precipitates. The solutions agree with the Monte Carlo simulation results.
NASA Technical Reports Server (NTRS)
Watson, James F., III; Desrochers, Alan A.
1991-01-01
Generalized stochastic Petri nets (GSPNs) are applied to flexible manufacturing systems (FMSs). Throughput subnets and s-transitions are presented. Two FMS examples containing nonexponential distributions which were analyzed in previous papers by queuing theory and probability theory, respectively, are treated using GSPNs developed using throughput subnets and s-transitions. The GSPN results agree with the previous results, and developing and analyzing the GSPN models are straightforward and relatively easy compared to other methodologies.
A generalized target theory and its applications.
Zhao, Lei; Mi, Dong; Hu, Bei; Sun, Yeqing
2015-09-28
Different radiobiological models have been proposed to estimate the cell-killing effects, which are very important in radiotherapy and radiation risk assessment. However, most applied models have their own scopes of application. In this work, by generalizing the relationship between "hit" and "survival" in traditional target theory with Yager negation operator in Fuzzy mathematics, we propose a generalized target model of radiation-induced cell inactivation that takes into account both cellular repair effects and indirect effects of radiation. The simulation results of the model and the rethinking of "the number of targets in a cell" and "the number of hits per target" suggest that it is only necessary to investigate the generalized single-hit single-target (GSHST) in the present theoretical frame. Analysis shows that the GSHST model can be reduced to the linear quadratic model and multitarget model in the low-dose and high-dose regions, respectively. The fitting results show that the GSHST model agrees well with the usual experimental observations. In addition, the present model can be used to effectively predict cellular repair capacity, radiosensitivity, target size, especially the biologically effective dose for the treatment planning in clinical applications.
3D Finite Element Analysis of Particle-Reinforced Aluminum
NASA Technical Reports Server (NTRS)
Shen, H.; Lissenden, C. J.
2002-01-01
Deformation in particle-reinforced aluminum has been simulated using three distinct types of finite element model: a three-dimensional repeating unit cell, a three-dimensional multi-particle model, and two-dimensional multi-particle models. The repeating unit cell model represents a fictitious periodic cubic array of particles. The 3D multi-particle (3D-MP) model represents randomly placed and oriented particles. The 2D generalized plane strain multi-particle models were obtained from planar sections through the 3D-MP model. These models were used to study the tensile macroscopic stress-strain response and the associated stress and strain distributions in an elastoplastic matrix. The results indicate that the 2D model having a particle area fraction equal to the particle representative volume fraction of the 3D models predicted the same macroscopic stress-strain response as the 3D models. However, there are fluctuations in the particle area fraction in a representative volume element. As expected, predictions from 2D models having different particle area fractions do not agree with predictions from 3D models. More importantly, it was found that the microscopic stress and strain distributions from the 2D models do not agree with those from the 3D-MP model. Specifically, the plastic strain distribution predicted by the 2D model is banded along lines inclined at 45 deg from the loading axis while the 3D model prediction is not. Additionally, the triaxial stress and maximum principal stress distributions predicted by 2D and 3D models do not agree. Thus, it appears necessary to use a multi-particle 3D model to accurately predict material responses that depend on local effects, such as strain-to-failure, fracture toughness, and fatigue life.
Aeolian dunes as ground truth for atmospheric modeling on Mars
Hayward, R.K.; Titus, T.N.; Michaels, T.I.; Fenton, L.K.; Colaprete, A.; Christensen, P.R.
2009-01-01
Martian aeolian dunes preserve a record of atmosphere/surface interaction on a variety of scales, serving as ground truth for both Global Climate Models (GCMs) and mesoscale climate models, such as the Mars Regional Atmospheric Modeling System (MRAMS). We hypothesize that the location of dune fields, expressed globally by geographic distribution and locally by dune centroid azimuth (DCA), may record the long-term integration of atmospheric activity across a broad area, preserving GCM-scale atmospheric trends. In contrast, individual dune morphology, as expressed in slipface orientation (SF), may be more sensitive to localized variations in circulation, preserving topographically controlled mesoscale trends. We test this hypothesis by comparing the geographic distribution, DCA, and SF of dunes with output from the Ames Mars GCM and, at a local study site, with output from MRAMS. When compared to the GCM: 1) dunes generally lie adjacent to areas with strongest winds, 2) DCA agrees fairly well with GCM modeled wind directions in smooth-floored craters, and 3) SF does not agree well with GCM modeled wind directions. When compared to MRAMS modeled winds at our study site: 1) DCA generally coincides with the part of the crater where modeled mean winds are weak, and 2) SFs are consistent with some weak, topographically influenced modeled winds. We conclude that: 1) geographic distribution may be valuable as ground truth for GCMs, 2) DCA may be useful as ground truth for both GCM and mesoscale models, and 3) SF may be useful as ground truth for mesoscale models. Copyright 2009 by the American Geophysical Union.
Statistics on Blindness in the Model Reporting Area 1969-1970.
ERIC Educational Resources Information Center
Kahn, Harold A.; Moorhead, Helen B.
Presented in the form of 30 tables are statistics on blindness in 16 states which have agreed to uniform definitions and procedures to improve reliability of data regarding blind persons. The data indicates that rates of blindness were generally higher for nonwhites than for whites with the ratio ranging from almost 10 for glaucoma to minimal for…
Recent Papers in Parametric Modelling of Time Series.
1983-04-01
conceptually R t A A different ways. First if one is Interested in savi 8h t~p t,p ,p parameters, then a resolution comparable to the . t -) Let’s agree to...has been affected most. Continue to next page for Figures 2 through 7 CONCLUSIONS We have presented a general framwork for de- riving and
Determinants of Presence in 3D Virtual Worlds: A Structural Equation Modelling Analysis
ERIC Educational Resources Information Center
Chow, Meyrick
2016-01-01
There is a growing body of evidence that feeling present in virtual environments contributes to effective learning. Presence is a psychological state of the user; hence, it is generally agreed that individual differences in user characteristics can lead to different experiences of presence. Despite the fact that user characteristics can play a…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-10-14
..., in general, agree with their substance. But we might have found it necessary to use different words...: It has been found that certain regions of the elevators, elevators trim tabs, and ailerons do not present drain holes to avoid water accumulation inside of these flight control surfaces. Internal water...
A novel cadaver-based educational program in general surgery training.
Lewis, Catherine E; Peacock, Warwick J; Tillou, Areti; Hines, O Joe; Hiatt, Jonathan R
2012-01-01
To describe the development of a cadaver-based educational program and report our residents' assessment of the new program. An anatomy-based educational program was developed using fresh frozen cadavers to teach surgical anatomy and operative skills to general surgery (GS) trainees. Residents were asked to complete a voluntary, anonymous survey evaluating perceptions of the program (6 questions formulated on a 5-point Likert scale) and comparing cadaver sessions to other types of learning (4 rank order questions). Large university teaching hospital. Medical students, residents, and faculty members were participants in the cadaver programs. Only GS residents were asked to complete the survey. Since its implementation, 150 residents of all levels participated in 13 sessions. A total of 40 surveys were returned for a response rate of 89%. Overall, respondents held a positive view of the cadaver sessions and believed them to be useful for learning anatomy (94% agree or strongly agree), learning the steps of an operation (76% agree or strongly agree), and increasing confidence in doing an operation (53% agree or strongly agree). Trainees wanted to have more sessions (87% agree or strongly agree), and believed they would spend free time in the cadaver laboratory (58% agree or strongly agree). Compared with other learning modalities, cadaver sessions were ranked first for learning surgical anatomy, followed by textbooks, simulators, web sites, animate laboratories, and lectures. Respondents also ranked cadaver sessions first for increasing confidence in performing a procedure and for learning the steps of an operation. Cost of cadavers represented the major expense of the program. Fresh cadaver dissections represent a solution to the challenges of efficient, safe, and effective general surgery education. Residents have a positive attitude toward these teaching sessions and found them to be more effective than other learning modalities. Copyright © 2012 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.
Informant Agreement in Treatment Gains for Child Anxiety
ERIC Educational Resources Information Center
Benjamin, Courtney L.; Puleo, Connor M.; Kendall, Philip C.
2011-01-01
The present study examined multiple informant agreement in reports of treatment gains in a sample of children (M age = 10.27) treated for social phobia, generalized anxiety disorder, and separation anxiety disorder. Mothers and fathers agreed on their child's improvement, and parents and children also generally agreed on the child's improvement.…
Pediatric dentists' perspective of general dentists' role in treating children aged 0-3 years.
Coe, Julie M; Razdan, Shinjni; Best, Al M; Brickhouse, Tegwyn H
2017-01-01
This study examined pediatric dentists' perspectives on the types of dental services general dentists provide to children who are 0-3 years old. A web-based survey was sent to 5185 pediatric dentists and 769 (14.8%) responded. Among the respondents, 58% agreed with general dentists' providing an age 1 dental visit. Only 24% agreed with general dentists' performing complex behavior management techniques, such as sedation, to patients aged 0-3 years. Those respondents who taught pediatric dentistry full time were more likely to agree with general dentists' providing an age 1 dental visit (P = 0.0088). Those who reported that their own dental school had adequately prepared them for this type of age 1 visit were also more in agreement (P < 0.0001). The results of this study promote better understanding of pediatric dentists' perceptions of the level of collaboration between general dentists and pediatric dentists; the types of oral health services general dentists can provide for children aged 0-3 years; and the anticipated level of competency of entry-level general dentists.
Analytical ground state for the Jaynes-Cummings model with ultrastrong coupling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang Yuanwei; Institute of Theoretical Physics, Shanxi University, Taiyuan 030006; Chen Gang
2011-06-15
We present a generalized variational method to analytically obtain the ground-state properties of the Jaynes-Cummings model with the ultrastrong coupling. An explicit expression for the ground-state energy, which agrees well with the numerical simulation in a wide range of the experimental parameters, is given. In particular, the introduced method can successfully solve this Jaynes-Cummings model with the positive detuning (the atomic resonant level is larger than the photon frequency), which cannot be treated in the adiabatical approximation and the generalized rotating-wave approximation. Finally, we also demonstrate analytically how to control the mean photon number by means of the current experimentalmore » parameters including the photon frequency, the coupling strength, and especially the atomic resonant level.« less
Effects of Simulated Land-Use Changes on Water Quality of Lake Maumelle, Arkansas
Hart, Rheannon M.; Westerman, Drew A.; Petersen, James C.; Green, W. Reed; De Lanois, Jeanne L.
2011-01-01
Lake Maumelle is one of two principal drinking-water supplies for the Little Rock and North Little Rock metropolitan areas. Lake Maumelle and the Maumelle River (its primary tributary) are more pristine than most other reservoirs and streams in the region. However, as the Lake Maumelle watershed becomes increasingly more urbanized and timber harvesting becomes more frequent, concerns about the sustainability of the quality of the water supply also have increased. Two models were developed to partially address these concerns. A Hydrological Simulation Program-FORTRAN model was developed using input data collected from October 2004 through 2008. A CE-QUAL-W2 model was developed to simulate reservoir hydrodynamics and selected water quality using the simulated output from the Hydrological Simulation Program-FORTRAN model from January 2005 through 2008. The Hydrological Simulation Program-FORTRAN watershed model was calibrated to five streamflow-gaging stations, and in general, these stations characterize a range of subwatershed areas with varying land-use types. Continuous streamflow data, discrete sediment concentration data, and other discrete water-quality data were used to calibrate the Lake Maumelle Hydrological Simulation Program-FORTRAN model. The CE-QUAL-W2 reservoir model was calibrated to water-quality data and reservoir pool altitude collected during January 2005 through December 2008 at three lake stations. In general, the overall simulation for the Hydrological Simulation Program-FORTRAN and CE-UAL-W2 models matched reasonably well to the measured data. In general, simulated and measured suspended-sediment concentrations during periods of base flow (streamflows not substantially influenced by runoff) agree reasonably well for Williams Junction (with differences-simulated minus measured value-generally ranging from -14 to 19 mg/L, and percent difference-relative to the measured value-ranging from -87 to 642 percent) and Wye (differences generally ranging from -2 to 14 mg/L, -62 to 251 percent); however, the Hydrological Simulation Program-FORTRAN model generally does not match the suspended-sediment concentrations for all stations during periods of stormflow (streamflow substantially influenced by runoff). Generally, this is also the case for fecal coliform bacteria numbers and total organic carbon and nutrient concentrations. In general, water temperature and dissolved-oxygen concentration simulations followed measured seasonal trends for all stations with the largest differences occurring during periods of lowest water temperatures (for temperature) or during the periods of lowest measured dissolved-oxygen concentrations (for dissolved oxygen). For the CE-QUAL-W2 model, simulated vertical distributions of temperatures and dissolved-oxygen concentrations agreed with measured distributions even for complex temperature profiles. Considering the oligotrophic-mesotrophic (low to intermediate primary productivity and associated low nutrient concentrations) condition of Lake Maumelle, simulated algae, phosphorus, and ammonia concentrations compared well with generally low measured values.
ERIC Educational Resources Information Center
Kaiser, Heather
2017-01-01
The effectiveness of teacher professional development (PD) has been scrutinized for decades. Although scholars generally agree that collaboration is a critical component of sustainable PD, among schools in the United States, time for collaboration embedded within the school day is lacking. In the most recent era of social media, school districts…
NASA Technical Reports Server (NTRS)
Ni, W.-T.
1973-01-01
A new relativistic theory of gravity is presented. This theory agrees with all experiments to date. It is a metric theory; it is Lagrangian-based; and it possesses a preferred frame with conformally flat space slices. With an appropriate choice of certain adjustable functions and parameters and of the cosmological model, this theory possesses precisely the same post-Newtonian limit as general relativity.
Latella, Lauren E.; McAuley, Robert J.; Rabinowitz, Mitchell
2018-01-01
The current study compares health care professionals’ beliefs about vaccination statements with the beliefs of a sample of individuals from the general population. Students and faculty within a medical school (n = 58) and a sample from the general population in the United States (n = 177) were surveyed regarding their beliefs about vaccinations. Participants evaluated statements about vaccinations (both supporting and opposing), and indicated whether they thought the general population would agree with them. Overall, it was found that subjects in both populations agreed with statements supporting vaccination over opposing statements, but the general population was more likely to categorize the supporting statements as beliefs rather than facts. Additionally, there was little consensus within each population as to which statements were considered facts versus beliefs. Both groups underestimated the number of people that would agree with them; however, the medical affiliates showed the effect significantly more. Implications for medical education and health communication are discussed. PMID:29597319
Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro
2015-04-05
The generalized Born model in the Onufriev, Bashford, and Case (Onufriev et al., Proteins: Struct Funct Genet 2004, 55, 383) implementation has emerged as one of the best compromises between accuracy and speed of computation. For simulations of nucleic acids, however, a number of issues should be addressed: (1) the generalized Born model is based on a linear model and the linearization of the reference Poisson-Boltmann equation may be questioned for highly charged systems as nucleic acids; (2) although much attention has been given to potentials, solvation forces could be much less sensitive to linearization than the potentials; and (3) the accuracy of the Onufriev-Bashford-Case (OBC) model for nucleic acids depends on fine tuning of parameters. Here, we show that the linearization of the Poisson Boltzmann equation has mild effects on computed forces, and that with optimal choice of the OBC model parameters, solvation forces, essential for molecular dynamics simulations, agree well with those computed using the reference Poisson-Boltzmann model. © 2015 Wiley Periodicals, Inc.
Schneider, Christopher; Newhauser, Wayne; Farah, Jad
2015-05-18
Exposure to stray neutrons increases the risk of second cancer development after proton therapy. Previously reported analytical models of this exposure were difficult to configure and had not been investigated below 100 MeV proton energy. The purposes of this study were to test an analytical model of neutron equivalent dose per therapeutic absorbed dose at 75 MeV and to improve the model by reducing the number of configuration parameters and making it continuous in proton energy from 100 to 250 MeV. To develop the analytical model, we used previously published H/D values in water from Monte Carlo simulations of a general-purpose beamline for proton energies from 100 to 250 MeV. We also configured and tested the model on in-air neutron equivalent doses measured for a 75 MeV ocular beamline. Predicted H/D values from the analytical model and Monte Carlo agreed well from 100 to 250 MeV (10% average difference). Predicted H/D values from the analytical model also agreed well with measurements at 75 MeV (15% average difference). The results indicate that analytical models can give fast, reliable calculations of neutron exposure after proton therapy. This ability is absent in treatment planning systems but vital to second cancer risk estimation.
Raetrad model extensions for radon entry into multi-level buildings with basements or crawl spaces.
Nielson, K K; Rogers, V C; Rogers, V; Holt, R B
1997-10-01
The RAETRAD model was generalized to characterize radon generation and movement from soils and building materials into multi-level buildings with basements or crawl spaces. With the generalization, the model retains its original simplicity and ease of use. The model calculates radon entry rates that are consistent with measurements published for basement test structures at Colorado State University, confirming approximately equal contributions from diffusion and pressure-driven air flow at indoor-outdoor air pressure differences of deltaP(i-o) = -3.5 Pa. About one-fourth of the diffusive radon entry comes from concrete slabs and three-fourths comes from the surrounding soils. Calculated radon entry rates with and without a barrier over floor-wall shrinkage cracks generally agree with Colorado State University measurements when a sustained pressure of deltaP(i-o) = -2 Pa is used to represent calm wind (<1 m s(-1)) conditions. Calculated radon distributions in a 2-level house also are consistent with published measurements and equations.
Communication: Introducing prescribed biases in out-of-equilibrium Markov models
NASA Astrophysics Data System (ADS)
Dixit, Purushottam D.
2018-03-01
Markov models are often used in modeling complex out-of-equilibrium chemical and biochemical systems. However, many times their predictions do not agree with experiments. We need a systematic framework to update existing Markov models to make them consistent with constraints that are derived from experiments. Here, we present a framework based on the principle of maximum relative path entropy (minimum Kullback-Leibler divergence) to update Markov models using stationary state and dynamical trajectory-based constraints. We illustrate the framework using a biochemical model network of growth factor-based signaling. We also show how to find the closest detailed balanced Markov model to a given Markov model. Further applications and generalizations are discussed.
Toxicity of Nanoparticles and an Overview of Current Experimental Models.
Bahadar, Haji; Maqbool, Faheem; Niaz, Kamal; Abdollahi, Mohammad
2016-01-01
Nanotechnology is a rapidly growing field having potential applications in many areas. Nanoparticles (NPs) have been studied for cell toxicity, immunotoxicity, and genotoxicity. Tetrazolium-based assays such as MTT, MTS, and WST-1 are used to determine cell viability. Cell inflammatory response induced by NPs is checked by measuring inflammatory biomarkers, such as IL-8, IL-6, and tumor necrosis factor, using ELISA. Lactate dehydrogenase (LDH) assay is used for cell membrane integrity. Different types of cell cultures, including cancer cell lines have been employed as in vitro toxicity models. It has been generally agreed that NPs interfere with either assay materials or with detection systems. So far, toxicity data generated by employing such models are conflicting and inconsistent. Therefore, on the basis of available experimental models, it may be difficult to judge and list some of the more valuable NPs as more toxic to biological systems and vice versa. Considering the potential applications of NPs in many fields and the growing apprehensions of FDA about the toxic potential of nanoproducts, it is the need of the hour to look for new internationally agreed free of bias toxicological models by focusing more on in vivo studies.
Cost-consciousness among Swiss doctors: a cross-sectional survey.
Bovier, Patrick A; Martin, Diane P; Perneger, Thomas V
2005-11-10
Knowing what influences physicians attitudes toward health care costs is an important matter, because most health care expenditures are the results of doctors' decisions. Many decisions regarding medical tests and treatments are influenced by factors other than the expected benefit to the patient, including the doctor's demographic characteristics and concerns about cost and income. Doctors (n = 1184) in Geneva, Switzerland, answered questions about their cost-consciousness, practice patterns (medical specialty, public.vs. private sector, number of patients per week, time spent with a new patient), work satisfaction, and stress from uncertainty. General linear models were used to identify independent risk factors of higher cost-consciousness. Most doctors agreed that trying to contain costs was their responsibility ("agree" or "totally agree": 90%) and that they should take a more prominent role in limiting the use of unnecessary tests (92%); most disagreed that doctors are too busy to worry about costs (69%) and that the cost of health care is only important if the patient has to pay for it out-of-pocket (88%). In multivariate analyses, cost-consciousness was higher among doctors in the public sector, those who saw fewer patients per week, who were most tolerant of uncertainty, and who were most satisfied with their work. Thus even in a setting with very high health care expenditures, doctors' stated cost-consciousness appeared to be generally high, even though it was not uniformly distributed among them.
1984-12-01
to be neither too high, nor too low. They agreed that the flexible progress payment model is too complex to administer, Very few agreed that the flow...Progress Payment Rate ....................... 133 Flexible Progress Payment Model ................... 146 Flow Down of Financing Provisions...Flexible Progress Payment Model A plurality (45%) of all respondents agreed that the flexible progress payment model is too
41 CFR 102-85.155 - What does a customer agency do if it does not agree with a Rent bill?
Code of Federal Regulations, 2010 CFR
2010-07-01
... of a customer agency may further appeal to the Administrator of the General Services. Documentation... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What does a customer... customer agency do if it does not agree with a Rent bill? (a) If a customer agency does not agree with the...
Ozone Profiles and Tropospheric Ozone from Global Ozone Monitoring Experiment
NASA Technical Reports Server (NTRS)
Liu, X.; Chance, K.; Sioris, C. E.; Sparr, R. J. D.; Kuregm, T. P.; Martin, R. V.; Newchurch, M. J.; Bhartia, P. K.
2003-01-01
Ozone profiles are derived from backscattered radiances in the ultraviolet spectra (290-340 nm) measured by the nadir-viewing Global Ozone Monitoring Experiment using optimal estimation. Tropospheric O3 is directly retrieved with the tropopause as one of the retrieval levels. To optimize the retrieval and improve the fitting precision needed for tropospheric O3, we perform extensive wavelength and radiometric calibrations and improve forward model inputs. Retrieved O3 profiles and tropospheric O3 agree well with coincident ozonesonde measurements, and the integrated total O3 agrees very well with Earth Probe TOMS and Dobson/Brewer total O3. The global distribution of tropospheric O3 clearly shows the influences of biomass burning, convection, and air pollution, and is generally consistent with our current understanding.
Crowley, Des; Collins, Claire; Delargy, Ide; Laird, Eamon; Van Hout, Marie Claire
2017-01-13
Governmental debate in Ireland on the de facto decriminalisation of cannabis and legalisation for medical use is ongoing. A cannabis-based medicinal product (Sativex®) has recently been granted market authorisation in Ireland. This unique study aimed to investigate Irish general practitioner (GP) attitudes toward decriminalisation of cannabis and assess levels of support for use of cannabis for therapeutic purposes (CTP). General practitioners in the Irish College of General Practitioner (ICGP) database were invited to complete an online survey. Anonymous data yielded descriptive statistics (frequencies, percentages) to summarise participant demographic information and agreement with attitudinal statements. Chi-square tests and multi-nominal logistic regression were included. The response rate was 15% (n = 565) which is similar to other Irish national GP attitudinal surveys. Over half of Irish GPs did not support the decriminalisation of cannabis (56.8%). In terms of gender, a significantly higher proportion of males compared with females (40.6 vs. 15%; p < 0.0001) agreed or strongly agreed with this drug policy approach. A higher percentage of GPs with advanced addiction specialist training (level 2) agreed/strongly agreed that cannabis should be decriminalised (54.1 vs. 31.5%; p = 0.021). Over 80% of both genders supported the view that cannabis use has a significant effect on patients' mental health and increases the risk of schizophrenia (77.3%). Over half of Irish GPs supported the legalisation of cannabis for medical use (58.6%). A higher percentage of those who were level 1-trained (trained in addiction treatment but not to an advanced level) agreed/strongly agreed cannabis should be legalised for medical use (p = 0.003). Over 60% agreed that cannabis can have a role in palliative care, pain management and treatment of multiple sclerosis (MS). In the regression response predicator analysis, females were 66.2% less likely to agree that cannabis should be decriminalised, 42.5% less likely to agree that cannabis should be legalised for medical use and 59.8 and 37.6% less likely to agree that cannabis has a role in palliative care and in the treatment of multiple sclerosis (respectively) than males. The majority of Irish GPs do not support the present Irish governmental drug policy of decriminalisation of cannabis but do support the legalisation of cannabis for therapeutic purposes. Male GPs and those with higher levels of addiction training are more likely to support a more liberal drug policy approach to cannabis for personal use. A clear majority of GPs expressed significant concerns regarding both the mental and physical health risks of cannabis use. Ongoing research into the health and other effects of drug policy changes on cannabis use is required.
NASA Astrophysics Data System (ADS)
Kryuchkov, V. P.
1996-03-01
Photogeologic mapping of 1:10M scale of the area of 37.5 degrees to 82.5 degrees N and 140 degrees to 260 degrees E have been made. The observed stratigraphic relations generally agree with the model of Venus stratigraphy of Basilevsky and Head (1995) but several contradictions with the model have been found (age relation between the ridge belts and densely fractured terrains). Important details of corona evolution have been revealed.
Host shifts and evolutionary radiations of butterflies
Fordyce, James A.
2010-01-01
Ehrlich and Raven proposed a model of coevolution where major host plant shifts of butterflies facilitate a burst of diversification driven by their arrival to a new adaptive zone. One prediction of this model is that reconstructions of historical diversification of butterflies should indicate an increase in diversification rate following major host shifts. Using reconstructed histories of 15 butterfly groups, I tested this prediction and found general agreement with Ehrlich and Raven's model. Butterfly lineages with an inferred major historical host shift showed evidence of diversification rate variation, with a significant acceleration following the host shift. Lineages without an inferred major host shift generally agreed with a constant-rate model of diversification. These results are consistent with the view that host plant associations have played a profound role in the evolutionary history of butterflies, and show that major shifts to chemically distinct plant groups leave a historical footprint that remains detectable today. PMID:20610430
NASA Technical Reports Server (NTRS)
Sun, S. F.
1985-01-01
The Ground Hydrologic Model (GHM) developed for use in an atmospheric general circulation model (GCM) has been refined. A series of sensitivity studies of the new version of the GHM were conducted for the purpose of understanding the role played by various physical parameters in the GHM. The following refinements have been made: (1) the GHM is coupled directly with the planetary boundary layer (PBL); (2) a bulk vegetation layer is added with a more realistic large-scale parameterization; and (3) the infiltration rate is modified. This version GHM has been tested using input data derived from a GCM simulation run for eight North America regions for 45 days. The results are compared with those of the resident GHM in the GCM. The daily average of grid surface temperatures from both models agree reasonably well in phase and magnitude. However, large difference exists in one or two regions on some days. The daily average evapotranspiration is in general 10 to 30% less than the corresponding value given by the resident GHM.
Mechanical-Electrochemical-Thermal Simulation of Lithium-Ion Cells
DOE Office of Scientific and Technical Information (OSTI.GOV)
Santhanagopalan, Shriram; Zhang, Chao; Sprague, Michael A.
2016-06-01
Models capture the force response for single-cell and cell-string levels to within 15%-20% accuracy and predict the location for the origin of failure based on the deformation data from the experiments. At the module level, there is some discrepancy due to poor mechanical characterization of the packaging material between the cells. The thermal response (location and value of maximum temperature) agrees qualitatively with experimental data. In general, the X-plane results agree with model predictions to within 20% (pending faulty thermocouples, etc.); the Z-plane results show a bigger variability both between the models and test-results, as well as among multiple repeatsmore » of the tests. The models are able to capture the timing and sequence in voltage drop observed in the multi-cell experiments; the shapes of the current and temperature profiles need more work to better characterize propagation. The cells within packaging experience about 60% less force under identical impact test conditions, so the packaging on the test articles is robust. However, under slow-crush simulations, the maximum deformation of the cell strings with packaging is about twice that of cell strings without packaging.« less
The origin of continental crust: Outlines of a general theory
NASA Technical Reports Server (NTRS)
Lowman, P. D., Jr.
1985-01-01
The lower continental crust, formerly very poorly understood, has recently been investigated by various geological and geophysical techniques that are beginning to yield a generally agreed on though still vague model (Lowman, 1984). As typified by at least some exposed high grade terranes, such as the Scottish Scourian complex, the lower crust in areas not affected by Phanerozoic orogeny or crustal extension appears to consist of gently dipping granulite gneisses of intermediate bulk composition, formed from partly or largely supracrustal precursors. This model, to the degree that it is correct, has important implications for early crustal genesis and the origin of continental crust in general. Most important, it implies that except for areas of major overthrusting (which may of course be considerable) normal superposition relations prevail, and that since even the oldest exposed rocks are underlain by tens of kilometers of sial, true primordial crust may still survive in the lower crustal levels (of. Phinney, 1981).
Tijmstra, Jesper; Bolsinova, Maria; Jeon, Minjeong
2018-01-10
This article proposes a general mixture item response theory (IRT) framework that allows for classes of persons to differ with respect to the type of processes underlying the item responses. Through the use of mixture models, nonnested IRT models with different structures can be estimated for different classes, and class membership can be estimated for each person in the sample. If researchers are able to provide competing measurement models, this mixture IRT framework may help them deal with some violations of measurement invariance. To illustrate this approach, we consider a two-class mixture model, where a person's responses to Likert-scale items containing a neutral middle category are either modeled using a generalized partial credit model, or through an IRTree model. In the first model, the middle category ("neither agree nor disagree") is taken to be qualitatively similar to the other categories, and is taken to provide information about the person's endorsement. In the second model, the middle category is taken to be qualitatively different and to reflect a nonresponse choice, which is modeled using an additional latent variable that captures a person's willingness to respond. The mixture model is studied using simulation studies and is applied to an empirical example.
Reactor pressure vessel embrittlement: Insights from neural network modelling
NASA Astrophysics Data System (ADS)
Mathew, J.; Parfitt, D.; Wilford, K.; Riddle, N.; Alamaniotis, M.; Chroneos, A.; Fitzpatrick, M. E.
2018-04-01
Irradiation embrittlement of steel pressure vessels is an important consideration for the operation of current and future light water nuclear reactors. In this study we employ an ensemble of artificial neural networks in order to provide predictions of the embrittlement using two literature datasets, one based on US surveillance data and the second from the IVAR experiment. We use these networks to examine trends with input variables and to assess various literature models including compositional effects and the role of flux and temperature. Overall, the networks agree with the existing literature models and we comment on their more general use in predicting irradiation embrittlement.
NASA Technical Reports Server (NTRS)
Intriligator, Devrie S.; Detman, Thomas; Gloecker, George; Gloeckler, Christine; Dryer, Murray; Sun, Wei; Intriligator, James; Deehr, Charles
2012-01-01
We report the first comparisons of pickup proton simulation results with in situ measurements of pickup protons obtained by the SWICS instrument on Ulysses. Simulations were run using the three dimensional (3D) time-dependent Hybrid Heliospheric Modeling System with Pickup Protons (HHMS-PI). HHMS-PI is an MHD solar wind model, expanded to include the basic physics of pickup protons from neutral hydrogen that drifts into the heliosphere from the local interstellar medium. We use the same model and input data developed by Detman et al. (2011) to now investigate the pickup protons. The simulated interval of 82 days in 2003 2004, includes both quiet solar wind (SW) and also the October November 2003 solar events (the Halloween 2003 solar storms). The HHMS-PI pickup proton simulations generally agree with the SWICS measurements and the HHMS-PI simulated solar wind generally agrees with SWOOPS (also on Ulysses) measurements. Many specific features in the observations are well represented by the model. We simulated twenty specific solar events associated with the Halloween 2003 storm. We give the specific values of the solar input parameters for the HHMS-PI simulations that provide the best combined agreement in the times of arrival of the solar-generated shocks at both ACE and Ulysses. We show graphical comparisons of simulated and observed parameters, and we give quantitative measures of the agreement of simulated with observed parameters. We suggest that some of the variations in the pickup proton density during the Halloween 2003 solar events may be attributed to depletion of the inflowing local interstellar medium (LISM) neutral hydrogen (H) caused by its increased conversion to pickup protons in the immediately preceding shock.
A resolution to authorize production of documents to the Department of Defense Inspector General.
Sen. Reid, Harry [D-NV
2009-01-08
Senate - 01/08/2009 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:
Deterministic Models of Inhalational Anthrax in New Zealand White Rabbits
2014-01-01
Computational models describing bacterial kinetics were developed for inhalational anthrax in New Zealand white (NZW) rabbits following inhalation of Ames strain B. anthracis. The data used to parameterize the models included bacterial numbers in the airways, lung tissue, draining lymph nodes, and blood. Initial bacterial numbers were deposited spore dose. The first model was a single exponential ordinary differential equation (ODE) with 3 rate parameters that described mucociliated (physical) clearance, immune clearance (bacterial killing), and bacterial growth. At 36 hours postexposure, the ODE model predicted 1.7×107 bacteria in the rabbit, which agreed well with data from actual experiments (4.0×107 bacteria at 36 hours). Next, building on the single ODE model, a physiological-based biokinetic (PBBK) compartmentalized model was developed in which 1 physiological compartment was the lumen of the airways and the other was the rabbit body (lung tissue, lymph nodes, blood). The 2 compartments were connected with a parameter describing transport of bacteria from the airways into the body. The PBBK model predicted 4.9×107 bacteria in the body at 36 hours, and by 45 hours the model showed all clearance mechanisms were saturated, suggesting the rabbit would quickly succumb to the infection. As with the ODE model, the PBBK model results agreed well with laboratory observations. These data are discussed along with the need for and potential application of the models in risk assessment, drug development, and as a general aid to the experimentalist studying inhalational anthrax. PMID:24527843
On a nonlinear Newtonian gravity and charging a black hole
NASA Astrophysics Data System (ADS)
Good, Michael R. R.
2018-06-01
A scalar field gravitational analog of the Reissner-Nordstrom solution is investigated. The nonlinear Newtonian model has an upper-limit of charge for a central mass, which agrees with the general relativistic condition required for the existence of the black hole horizon. The maximum limit for accumulation by bombardment of charged particles is found. The aim is to investigate the resulting physics after severing the effects of curvature from the effects of energy-mass equivalence.
15 CFR 904.214 - Stipulations.
Code of Federal Regulations, 2011 CFR
2011-01-01
... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE GENERAL REGULATIONS CIVIL PROCEDURES Hearing and Appeal Procedures General § 904.214 Stipulations. The parties may, by stipulation, agree upon any...
15 CFR 904.214 - Stipulations.
Code of Federal Regulations, 2010 CFR
2010-01-01
... AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE GENERAL REGULATIONS CIVIL PROCEDURES Hearing and Appeal Procedures General § 904.214 Stipulations. The parties may, by stipulation, agree upon any...
Enforcement of continuous compliance with air quality regulations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harrington, C.W.
1985-01-01
The compliance of stationary air-pollution sources with air quality regulations is examined. Contrary to the predictions of economic models of enforcement, sources are generally in continuous compliance with the regulations. An alternative voluntary compliance model of enforcement is proposed, in which regulated sources are penalized not for violations, but for failing to return to compliance when a violation is discovered. It is argued that continuous compliance is a bargain struck between the source and the regulatory agency, in which the agency agrees to avoid use of penalties in return for the source's good faith attempts to maintain compliance.
Anderson-Cook, Christine M.; Burke, Sarah E.
2016-10-18
First, we would like to commend Dr. Woods on his thought-provoking paper and insightful presentation at the 4th Annual Stu Hunter conference. We think that the material presented highlights some important needs in the area of design of experiments for generalized linear models (GLMs). In addition, we agree with Dr. Woods that design of experiements of GLMs does implicitly require expert judgement about model parameters, and hence using a Bayesian approach to capture this knowledge is a natural strategy to summarize what is known with the opportunity to incorporate associated uncertainty about that information.
Computational Modeling for the Flow Over a Multi-Element Airfoil
NASA Technical Reports Server (NTRS)
Liou, William W.; Liu, Feng-Jun
1999-01-01
The flow over a multi-element airfoil is computed using two two-equation turbulence models. The computations are performed using the INS2D) Navier-Stokes code for two angles of attack. Overset grids are used for the three-element airfoil. The computed results are compared with experimental data for the surface pressure, skin friction coefficient, and velocity magnitude. The computed surface quantities generally agree well with the measurement. The computed results reveal the possible existence of a mixing-layer-like region of flow next to the suction surface of the slat for both angles of attack.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson-Cook, Christine M.; Burke, Sarah E.
First, we would like to commend Dr. Woods on his thought-provoking paper and insightful presentation at the 4th Annual Stu Hunter conference. We think that the material presented highlights some important needs in the area of design of experiments for generalized linear models (GLMs). In addition, we agree with Dr. Woods that design of experiements of GLMs does implicitly require expert judgement about model parameters, and hence using a Bayesian approach to capture this knowledge is a natural strategy to summarize what is known with the opportunity to incorporate associated uncertainty about that information.
plasma focus . A generalized beam-target model is assumed where (1) high-energy deuterons have angular distributions consistent with a crossed-field acceleration mechanism, and (2) these energetic deuterons undergo fusion collisions primarily with stationary target ions. Energy distributions of ions proportional to 1/(E sub d) cubed in the range from 50 to as high as 600 keV give computed results agreeing with many experimental observations at laboratory angles of 0, 90, and 180 deg. These ion-energy distributions can account for a 50- to 100-fold increase in neutron yeild
Out-of-plane aerodynamic forces on slender ogive-nosed cylinders
NASA Astrophysics Data System (ADS)
Lacey, M. R.
An ogive-nosed cylinder with a nose fineness of 3 and a body length equal to 12 diameters, has been tested at a constant crossflow Reynolds' number of 85000 and constant crossflow Mach number of 0.1 in the angle of incidence range 0° - 90°, A method of force measurement has been devised to determine the magnitude of the aerodynamic forces on the ogive cylinder and a statistical analysis was developed to predict its accuracy for any model configuration. It was found generally that the results of static loading tests lay well within the stipulated accuracy limits. The out-of-plane forest and moments measured generally agreed well with published data and predictions based on experimental results. Similar agreement was obtained for in-plane forces and moments. The results for the effect of model roll-orientation on the out-of-plane force indicated the existence of two distinct states of asymmetry in the wake, with an absence of any intermediate states. The out-of-plane forces showed no correlation with the position of model nose imperfections, supporting the findings of previous experimenters. Reducing the length of the cylindrical body section of the model served first to reduce the out-of-plane force but subsequently produced a recovery in its magnitude with further shortening. These results agreed well with the prediction method selected. Increased free stream turbulence tended to have less effect on the distribution of the out-of-plane force than previously reported; no flow unsteadiness was observed and no change in direction of roce was recorded. Increased nose tip radius generally reduced the out- of plane force and considerable directional instability was observed. This reduction was, however, not true for all incidence angles. The directional instability was due probably to the removal of the nose tip imperfections, resulting in an inability of the wake to establish a preferred direction of asymmetry throughout the range of incidence.
A frost formation model and its validation under various experimental conditions
NASA Technical Reports Server (NTRS)
Dietenberger, M. A.
1982-01-01
A numerical model that was used to calculate the frost properties for all regimes of frost growth is described. In the first regime of frost growth, the initial frost density and thickness was modeled from the theories of crystal growth. The 'frost point' temperature was modeled as a linear interpolation between the dew point temperature and the fog point temperature, based upon the nucleating capability of the particular condensing surfaces. For a second regime of frost growth, the diffusion model was adopted with the following enhancements: the generalized correlation of the water frost thermal conductivity was applied to practically all water frost layers being careful to ensure that the calculated heat and mass transfer coefficients agreed with experimental measurements of the same coefficients.
Ballhausen, Hendrik; Belka, Claus
2017-03-01
To provide a rule for the agreement or disagreement of the Poisson approximation (PA) and the Zaider-Minerbo formula (ZM) on the ranking of treatment alternatives in terms of tumor control probability (TCP) in the linear quadratic model. A general criterion involving a critical cell birth rate was formally derived. For demonstration, the criterion was applied to a distinct radiobiological model of fast growing head and neck tumors and a respective range of 22 conventional and nonconventional head and neck schedules. There is a critical cell birth rate b crit below which PA and ZM agree on which one out of two alternative treatment schemes with single-cell survival curves S'(t) and S''(t) offers better TCP: [Formula: see text] For cell birth rates b above this critical cell birth rate, PA and ZM disagree if and only if b >b crit > 0. In case of the exemplary head and neck schedules, out of 231 possible combinations, only 16 or 7% were found where PA and ZM disagreed. In all 231 cases the prediction of the criterion was numerically confirmed, and cell birth rates at crossovers between schedules matched the calculated critical cell birth rates. TCP estimated by PA and ZM almost never numerically coincide. Still, in many cases both formulas at least agree about which one out of two alternative fractionation schemes offers better TCP. In case of fast growing tumors featuring a high cell birth rate, however, ZM may suggest a re-evaluation of treatment options.
Reshocks, rarefactions, and the generalized Layzer model for hydrodynamic instabilities
NASA Astrophysics Data System (ADS)
Mikaelian, Karnig O.
2009-02-01
We report numerical simulations and analytic modeling of shock tube experiments on Rayleigh-Taylor and Richtmyer-Meshkov instabilities. We examine single interfaces of the type A /B where the incident shock is initiated in A and the transmitted shock proceeds into B. Examples are He/air and air/He. In addition, we study finite-thickness or double-interface A /B/A configurations such as air/SF6/air gas-curtain experiments. We first consider conventional shock tubes that have a "fixed" boundary: A solid endwall which reflects the transmitted shock and reshocks the interface(s). Then we focus on new experiments with a "free" boundary—a membrane disrupted mechanically or by the transmitted shock, sending back a rarefaction toward the interface(s). Complex acceleration histories are achieved, relevant for inertial confinement fusion implosions. We compare our simulation results with a generalized Layzer model for two fluids with time-dependent densities and derive a new freeze-out condition whereby accelerating and compressive forces cancel each other out. Except for the recently reported failures of the Layzer model, the generalized Layzer model and hydrocode simulations for reshocks and rarefactions agree well with each other and remain to be verified experimentally.
NASA Astrophysics Data System (ADS)
Hu, Chuanmin; Lee, Zhongping; Muller-Karger, Frank E.; Carder, Kendall L.
2003-05-01
A spectra-matching optimization algorithm, designed for hyperspectral sensors, has been implemented to process SeaWiFS-derived multi-spectral water-leaving radiance data. The algorithm has been tested over Southwest Florida coastal waters. The total spectral absorption and backscattering coefficients can be well partitioned with the inversion algorithm, resulting in RMS errors generally less than 5% in the modeled spectra. For extremely turbid waters that come from either river runoff or sediment resuspension, the RMS error is in the range of 5-15%. The bio-optical parameters derived in this optically complex environment agree well with those obtained in situ. Further, the ability to separate backscattering (a proxy for turbidity) from the satellite signal makes it possible to trace water movement patterns, as indicated by the total absorption imagery. The derived patterns agree with those from concurrent surface drifters. For waters where CDOM overwhelmingly dominates the optical signal, however, the procedure tends to regard CDOM as the sole source of absorption, implying the need for better atmospheric correction and for adjustment of some model coefficients for this particular region.
Supersymmetric Sachdev-Ye-Kitaev models
Fu, Wenbo; Gaiotto, Davide; Maldacena, Juan; ...
2017-01-13
We discuss a supersymmetric generalization of the Sachdev-Ye-Kitaev (SYK) model. These are quantum mechanical models involving N Majorana fermions. The supercharge is given by a polynomial expression in terms of the Majorana fermions with random coefficients. The Hamiltonian is the square of the supercharge. The N = 1 model with a single supercharge has unbroken supersymmetry at large N , but nonperturbatively spontaneously broken supersymmetry in the exact theory. We analyze the model by looking at the large N equation, and also by performing numerical computations for small values of N . We also compute the large N spectrum ofmore » “singlet” operators, where we find a structure qualitatively similar to the ordinary SYK model. We also discuss an N = 2 version. In this case, the model preserves supersymmetry in the exact theory and we can compute a suitably weighted Witten index to count the number of ground states, which agrees with the large N computation of the entropy. In both cases, we discuss the supersymmetric generalizations of the Schwarzian action which give the dominant effects at low energies.« less
Absorbed fractions in a voxel-based phantom calculated with the MCNP-4B code.
Yoriyaz, H; dos Santos, A; Stabin, M G; Cabezas, R
2000-07-01
A new approach for calculating internal dose estimates was developed through the use of a more realistic computational model of the human body. The present technique shows the capability to build a patient-specific phantom with tomography data (a voxel-based phantom) for the simulation of radiation transport and energy deposition using Monte Carlo methods such as in the MCNP-4B code. MCNP-4B absorbed fractions for photons in the mathematical phantom of Snyder et al. agreed well with reference values. Results obtained through radiation transport simulation in the voxel-based phantom, in general, agreed well with reference values. Considerable discrepancies, however, were found in some cases due to two major causes: differences in the organ masses between the phantoms and the occurrence of organ overlap in the voxel-based phantom, which is not considered in the mathematical phantom.
42 CFR 417.484 - Requirement applicable to related entities.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 42 Public Health 3 2011-10-01 2011-10-01 false Requirement applicable to related entities. 417.484... entities. (a) Definition. As used in this section, related entity means any entity that is related to the... agrees to require all related entities to agree that— (1) HHS, the Comptroller General, or their...
42 CFR 417.484 - Requirement applicable to related entities.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 42 Public Health 3 2010-10-01 2010-10-01 false Requirement applicable to related entities. 417.484... entities. (a) Definition. As used in this section, related entity means any entity that is related to the... agrees to require all related entities to agree that— (1) HHS, the Comptroller General, or their...
The Schools and the Challenge of Innovation.
ERIC Educational Resources Information Center
James, H. Thomas; And Others
Papers contributed by authors prominent in educational innovation and technology are in this collected work. The authors do not always agree, but a broad pattern of agreement is discernible. They agree on the identification of those major problems confronting the schools today as a result of the new social forces at work; and generally, they agree…
22 CFR 171.14 - Fees to be charged-general.
Code of Federal Regulations, 2010 CFR
2010-04-01
... request, the requester shall be considered to have agreed to pay all applicable fees up to $25.00 unless a... requester agrees to pay the estimated fees. For both manual and computer searches, the Department shall... categories of personnel doing the searches. Further information on search fees is available by clicking on...
Hassali, Mohamed Azmi; Kamil, Tengku Karmila Tengku; Md Yusof, Faridah Aryani; Alrasheedy, Alian A; Yusoff, Zuraidah Mohd; Saleem, Fahad; Al-Tamimi, Saleh Karamah; Wong, Zhi Yen; Aljadhey, Hisham; Godman, Brian
2015-04-01
Antibiotics are widely prescribed especially for upper respiratory tract infections (URTIs). Their irrational use can increase costs and resistance. Assess knowledge, attitude and prescribing of antibiotics for URTIs in Selangor, Malaysia, using a cross-sectional survey among general practitioners (GPs) working in private clinics in 2011. One hundred and thirty-nine physicians completed the questionnaire (response rate = 34.8%). 49.6% (n = 69) agreed antibiotics are helpful in treating URTIs, with most GPs agreeing antibiotics may reduce URTI duration and complications. The majority of GPs reported they felt patients expected antibiotics, with 36.7% (n = 51) agreeing patients would change doctors if they did not prescribe antibiotics and 21.6% (n = 30) agreeing when requested they prescribe antibiotics even if they believe them to be unnecessary. When assessed against six criteria, most GPs had a moderate level of knowledge of prescribing for URTIs. However, antibiotic prescriptions could be appreciably reduced. Further programs are needed to educate GPs and patients about antibiotics building on current initiatives.
Ground-water models: Validate or invalidate
Bredehoeft, J.D.; Konikow, Leonard F.
1993-01-01
The word validation has a clear meaning to both the scientific community and the general public. Within the scientific community the validation of scientific theory has been the subject of philosophical debate. The philosopher of science, Karl Popper, argued that scientific theory cannot be validated, only invalidated. Popper’s view is not the only opinion in this debate; however, many scientists today agree with Popper (including the authors). To the general public, proclaiming that a ground-water model is validated carries with it an aura of correctness that we do not believe many of us who model would claim. We can place all the caveats we wish, but the public has its own understanding of what the word implies. Using the word valid with respect to models misleads the public; verification carries with it similar connotations as far as the public is concerned. Our point is this: using the terms validation and verification are misleading, at best. These terms should be abandoned by the ground-water community.
NASA Astrophysics Data System (ADS)
Arai, Shun; Nishizawa, Atsushi
2018-05-01
Gravitational waves (GW) are generally affected by modification of a gravity theory during propagation at cosmological distances. We numerically perform a quantitative analysis on Horndeski theory at the cosmological scale to constrain the Horndeski theory by GW observations in a model-independent way. We formulate a parametrization for a numerical simulation based on the Monte Carlo method and obtain the classification of the models that agrees with cosmic accelerating expansion within observational errors of the Hubble parameter. As a result, we find that a large group of the models in the Horndeski theory that mimic cosmic expansion of the Λ CDM model can be excluded from the simultaneous detection of a GW and its electromagnetic transient counterpart. Based on our result and the latest detection of GW170817 and GRB170817A, we conclude that the subclass of Horndeski theory including arbitrary functions G4 and G5 can hardly explain cosmic accelerating expansion without fine-tuning.
Aviation Safety: FAA Generally Agrees With But is Slow in Implementing Safety Recommendations
DOT National Transportation Integrated Search
1996-09-23
The Federal Aviation Administration (FAA), within the Department of : Transportation (DOT), is responsible for promoting safety in civil air : transportation. General Accounting Office (GAO) and DOT's Office of Inspector : General review FAA's safety...
Kinahan, Karen E; Kircher, Sheetal; Altman, Jessica; Rademaker, Alfred; Salsman, John M; Didwania, Aarati; O'Brien, Bridget; Patel, Alpa C; Sanford, Stacy D
2017-01-01
The "shared-care model" for patients with cancer involves care coordination between primary care providers (PCPs) and oncologists, with the goal of optimizing survivorship care. However, a high proportion of adolescent and young adult (AYA) cancer survivors do not have a PCP. Study objectives were to increase the percentage of AYAs with a PCP documented in the electronic medical record (EMR) via the use of a best practice advisory (BPA) or "stopgap" intervention; to increase communication between providers by the number of routed clinic notes; and to assess oncology providers' attitudes/beliefs about the model and intervention. Data were collected for the 6 months before implementation of the BPA to determine the percentage of AYAs with a PCP and the number of notes routed to providers (time point 1 [T1]). The same data were collected at time point 2 (T2) after the BPA had been implemented for 6 months. Oncology providers participated in an education video module and an online survey at T1 and a survey at T2. At T1, 47.1% of 756 AYAs had a documented PCP in the EMR. At T2, the percentage increased to 55.1% (P<.002). The number of routed notes did not change significantly from T1 to T2. Providers that completed the intervention survey agreed/strongly agreed that the shared-care model is a desirable model of care (T1 = 86%; T2 = 93%) and that a BPA is useful for facilitating PCP referrals (T1 = 76%; T2 = 39%). This BPA is feasible for increasing the percentage of AYAs with a PCP documented in the EMR and could potentially lead to increased PCP referral and communication among providers for the benefit of long-term survivorship care. Providers generally agree with the shared-care model; however, the BPA implementation requires modification. Copyright © 2017 by the National Comprehensive Cancer Network.
Critical current and linewidth reduction in spin-torque nano-oscillators by delayed self-injection
DOE Office of Scientific and Technical Information (OSTI.GOV)
Khalsa, Guru, E-mail: guru.khalsa@nist.gov; Stiles, M. D.; Grollier, J.
2015-06-15
Based on theoretical models, the dynamics of spin-torque nano-oscillators can be substantially modified by re-injecting the emitted signal to the input of the oscillator after some delay. Numerical simulations for vortex magnetic tunnel junctions show that with reasonable parameters this approach can decrease critical currents as much as 25% and linewidths by a factor of 4. Analytical calculations, which agree well with simulations, demonstrate that these results can be generalized to any kind of spin-torque oscillator.
On the opposing views of the self–nonself discrimination by the immune system
Cohn, Melvin
2010-01-01
Today’s generally accepted view of the self–nonself discrimination was voiced by Miller1 in 2004 in a thought-provoking essay. In spite of its popularity, this position has its limitations, which are analyzed here with a view toward establishing an interactive discussion that hopefully will culminate in agreed upon decisive experiments. The inadequacies of Miller’s view of the self–nonself discrimination and their resolution under the associative recognition of antigen model are analyzed. PMID:19048020
NASA Technical Reports Server (NTRS)
Halem, M.; Shukla, J.; Mintz, Y.; Wu, M. L.; Godbole, R.; Herman, G.; Sud, Y.
1979-01-01
Results are presented from numerical simulations performed with the general circulation model (GCM) for winter and summer. The monthly mean simulated fields for each integration are compared with observed geographical distributions and zonal averages. In general, the simulated sea level pressure and upper level geopotential height field agree well with the observations. Well simulated features are the winter Aleutian and Icelandic lows, the summer southwestern U.S. low, the summer and winter oceanic subtropical highs in both hemispheres, and the summer upper level Tibetan high and Atlantic ridge. The surface and upper air wind fields in the low latitudes are in good agreement with the observations. The geographical distirbutions of the Earth-atmosphere radiation balance and of the precipitation rates over the oceans are well simulated, but not all of the intensities of these features are correct. Other comparisons are shown for precipitation along the ITCZ, rediation balance, zonally averaged temperatures and zonal winds, and poleward transports of momentum and sensible heat.
Using surface impedance for calculating wakefields in flat geometry
Bane, Karl; Stupakov, Gennady
2015-03-18
Beginning with Maxwell's equations and assuming only that the wall interaction can be approximated by a surface impedance, we derive formulas for the generalized longitudinal and transverse impedance in flat geometry, from which the wakefields can also be obtained. From the generalized impedances, by taking the proper limits, we obtain the normal longitudinal, dipole, and quad impedances in flat geometry. These equations can be applied to any surface impedance, such as the known dc, ac, and anomalous skin models of wall resistance, a model of wall roughness, or one for a pipe with small, periodic corrugations. We show that, formore » the particular case of dc wall resistance, the longitudinal impedance obtained here agrees with a known result in the literature, a result that was derived from a very general formula by Henke and Napoly. As an example, we apply our results to representative beam and machine parameters in the undulator region of LCLS-II and estimate the impact of the transverse wakes on the machine performance.« less
Zhu, Lan; Lang, Jinghe
2018-01-01
Objective The study aimed to determine prevalence, patterns and risk factors of defensive medicine by obstetricians and gynaecologists across China. Design This is a questionnaire survey by written and on-line interview for participants. Participants Among 1804 registered physicians participating at the 2017 Congress of Chinese Obstetricians and Gynecologists Association in Chengdu City, Sichuan Province, China, from 17 to 20 August 2017, 1486 participants (82.4%) responded the survey. Main outcome measures Participants’ strongly disagreed/disagreed and strongly agreed/agreed options were compared to determine specific factors contributing to their preferences towards defensive medicine. Results In the whole cohort of 1486 participants, 903/1486 (60.8%), 283/1486 (19.0%) and 170/283 (60.1%) participants had experienced at least one medical dispute, lawsuit or loss of a lawsuit, respectively; and 1284 (86.4%) participants had witnessed their colleagues exposed to medical disputes, lawsuits or loss of a lawsuit. Generally, 62.9% of the participants strongly agreed or agreed with defensive medicine. Gender, administration duty, employment hospital, education status, subspecialty, exposure to any medical disputes, lawsuits or loss of a lawsuit, and colleagues’ experiences were independent risk factors relevant to participants’ preferences about defensive medicine in a multivariate model. Participants were more prone to accept or endorse defensive medicine if they were female physicians; without administrative duties; working in non-tertiary hospitals; with an undergraduate degree; with any exposure to medical disputes, lawsuits or loss of a lawsuit; or having witnessed colleagues’ similar experiences. Conclusions About two-thirds of Chinese physicians practising obstetrics and gynaecology in our survey agreed with the practice of defensive medicine, but they had diverse preferences and understanding of specific practices, harms of defensive medicine and physician’s roles. PMID:29431139
Aeroelastic Optimization of Generalized Tube and Wing Aircraft Concepts Using HCDstruct Version 2.0
NASA Technical Reports Server (NTRS)
Quinlan, Jesse R.; Gern, Frank H.
2017-01-01
Major enhancements were made to the Higher-fidelity Conceptual Design and structural optimization (HCDstruct) tool developed at NASA Langley Research Center (LaRC). Whereas previous versions were limited to hybrid wing body (HWB) configurations, the current version of HCDstruct now supports the analysis of generalized tube and wing (TW) aircraft concepts. Along with significantly enhanced user input options for all air- craft configurations, these enhancements represent HCDstruct version 2.0. Validation was performed using a Boeing 737-200 aircraft model, for which primary structure weight estimates agreed well with available data. Additionally, preliminary analysis of the NASA D8 (ND8) aircraft concept was performed, highlighting several new features of the tool.
NASA Astrophysics Data System (ADS)
Frauenfeld, O. W.; Peng, X.; Zhang, T.
2016-12-01
Both the thawing index (TI) and active layer thickness (ALT) can be useful indicators of climate change in cold regions and have important implications for various surface-atmosphere interactions. Here, we analyze the spatial and temporal variability of the Northern Hemisphere TI and ALT under historical and projected climate change. We combine gridded and station-based observations to assess the multi-model ensemble mean of 16 of the Coupled Model Intercomparison Project phase 5 (CMIP5) models over 1850-2005. The TI and ALT are assessed based on 1901-2014 Climatic Research Unit (CRU) data, and observational ALT from 348 station locations across the Northern Hemisphere. We then employ three representative concentration pathways (RCP 2.6, 4.5, and 8.5) from the same CMIP5 multi-model ensemble means to evaluate changes for 2006-2100. Over the historical period, the TI varies from 0-11,000°C-days in the Northern Hemisphere, and we find good agreement between CMIP5 models and CRU data; however, the models generally underestimate observed TI and its long-term trends. Over the 2006-2100 period, the multi-model ensemble averaged TI increases significantly for all three RCPs, ranging from 1.5°C-days/yr for RCP 2.6, to 14°C-days/yr for RCP 8.5. The spatial variations in ALT from observing stations exhibit significant variability and generally range from 80-320 cm across the Northern Hemisphere, with some extreme values of 900 cm in the European Alps. Calculating observational ALT for 1971-2000 from CRU, we find lower values (30-650 cm). The CMIP5 climatology agrees well with the CRU estimates. ALT trends over the observational period are generally less than 1.5 cm/decade, but as high as 3 cm/decade in some isolated regions. While this general trend magnitude agrees with that from CMIP5, the multi-model ensemble underestimates trends and exhibits much less spatial variability. Projected trends range from 0.77 cm/decade in RCP 2.6, to 6.5 cm/decade in RCP 8.5 in the permafrost regions across the Northern Hemisphere. Over the observational period, summer air temperature and precipitation are found to be the main drivers of ALT variability. However, the declining Arctic sea ice trend is also strongly negatively correlated with ALT increases, pointing to a common driver of these cryospheric changes.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 34 Education 1 2010-07-01 2010-07-01 false Do other Federal agencies know if the Department of Education agrees to a voluntary exclusion? 85.645 Section 85.645 Education Office of the Secretary, Department of Education GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) General Principles Relating...
NOAA and EUMETSAT agree to continued cooperation
NASA Astrophysics Data System (ADS)
Balcerak, Ernie
2013-09-01
The National Oceanic and Atmospheric Administration (NOAA) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) have agreed to continue their long-term cooperation on satellite-based weather monitoring. NOAA acting administrator Kathryn Sullivan and EUMETSAT director general Alain Ratier signed the agreement at a ceremony at the European Union Delegation in Washington, D. C., on 27 August.
Universal scaling for second-class particles in a one-dimensional misanthrope process
NASA Astrophysics Data System (ADS)
Rákos, Attila
2010-06-01
We consider the one-dimensional Katz-Lebowitz-Spohn (KLS) model, which is a generalization of the totally asymmetric simple exclusion process (TASEP) with nearest neighbour interaction. Using a powerful mapping, the KLS model can be translated into a misanthrope process. In this model, for the repulsive case, it is possible to introduce second-class particles, the number of which is conserved. We study the distance distribution of second-class particles in this model numerically and find that for large distances it decreases as x-3/2. This agrees with a previous analytical result of Derrida et al (1993) for the TASEP, where the same asymptotic behaviour was found. We also study the dynamical scaling function of the distance distribution and find that it is universal within this family of models.
NASA Astrophysics Data System (ADS)
Bodendorfer, N.; Schäfer, A.; Schliemann, J.
2018-04-01
Chamseddine and Mukhanov recently proposed a modified version of general relativity that implements the idea of a limiting curvature. In the spatially flat, homogeneous, and isotropic sector, their theory turns out to agree with the effective dynamics of the simplest version of loop quantum gravity if one identifies their limiting curvature with a multiple of the Planck curvature. At the same time, it extends to full general relativity without any symmetry assumptions and thus provides an ideal toy model for full loop quantum gravity in the form of a generally covariant effective action known to all orders. In this paper, we study the canonical structure of this theory and point out some interesting lessons for loop quantum gravity. We also highlight in detail how the two theories are connected in the spatially flat, homogeneous, and isotropic sector.
Free-flight investigation of forebody blowing for stability and control
NASA Technical Reports Server (NTRS)
Brandon, Jay M.; Simon, James M.; Owens, D. Bruce; Kiddy, Jason S.
1996-01-01
A free-flight wind-tunnel investigation was conducted on a generic fighter model with forebody pneumatic vortex control for high angle-of-attack directional control. This is believed to be the first flight demonstration of a forebody blowing concept integrated into a closed-loop flight control system for stability augmentation and control. The investigation showed that the static wind tunnel estimates of the yaw control available generally agreed with flight results. The control scheme for the blowing nozzles consisted of an on/off control with a deadband. Controlled flight was obtained for the model using forebody blowing for directional control to beyond 45 deg. angle of attack.
NASA Astrophysics Data System (ADS)
Jeong, Jina; Park, Eungyu; Shik Han, Weon; Kim, Kue-Young; Suk, Heejun; Beom Jo, Si
2018-07-01
A generalized water table fluctuation model based on precipitation was developed using a statistical conceptualization of unsaturated infiltration fluxes. A gamma distribution function was adopted as a transfer function due to its versatility in representing recharge rates with temporally dispersed infiltration fluxes, and a Laplace transformation was used to obtain an analytical solution. To prove the general applicability of the model, convergences with previous water table fluctuation models were shown as special cases. For validation, a few hypothetical cases were developed, where the applicability of the model to a wide range of unsaturated zone conditions was confirmed. For further validation, the model was applied to water table level estimations of three monitoring wells with considerably thick unsaturated zones on Jeju Island. The results show that the developed model represented the pattern of hydrographs from the two monitoring wells fairly well. The lag times from precipitation to recharge estimated from the developed system transfer function were found to agree with those from a conventional cross-correlation analysis. The developed model has the potential to be adopted for the hydraulic characterization of both saturated and unsaturated zones by being calibrated to actual data when extraneous and exogenous causes of water table fluctuation are limited. In addition, as it provides reference estimates, the model can be adopted as a tool for surveilling groundwater resources under hydraulically stressed conditions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1998-12-01
On October 6, 1997, the Department of Energy (DOE) announced it had agreed to sell all of the Government`s interest in Naval Petroleum Reserve Number 1 (NPR-1) to Occidental Petroleum Corporation for $3.65 billion. This report presents the results of the independent certified public accountants` agreed-upon procedures work on the Preliminary Settlement Statement of the Purchase and Sale Agreement between DOE and Occidental. To fulfill their responsibilities, the Office of Inspector General contracted with the independent public accounting firm of KPMG Peat Marwick LLP to conduct the work for them, subject to their review. The work was done in accordancemore » with the Statements on Standards for Attestation Engagements issued by the American Institute of Certified Public Accountants. As such, the independent certified public accountants performed only work that was agreed upon by DOE and Occidental. This report is intended solely for the use of DOE and Occidental and should not be used by those who have not agreed to the procedures and taken responsibility for the sufficiency of the procedures for their purposes. However, this report is a matter of public record, and its distribution is not limited. The independent certified public accountants identified over 20 adjustments to the Preliminary Settlement Statement that would result in a $10.8 million increase in the sale price.« less
NASA Astrophysics Data System (ADS)
Becker, Erich; Vadas, Sharon L.
2018-03-01
This study analyzes a new high-resolution general circulation model with regard to secondary gravity waves in the mesosphere during austral winter. The model resolves gravity waves down to horizontal and vertical wavelengths of 165 and 1.5 km, respectively. The resolved mean wave drag agrees well with that from a conventional model with parameterized gravity waves up to the midmesosphere in winter and up to the upper mesosphere in summer. About half of the zonal-mean vertical flux of westward momentum in the southern winter stratosphere is due to orographic gravity waves. The high intermittency of the primary orographic gravity waves gives rise to secondary waves that result in a substantial eastward drag in the winter mesopause region. This induces an additional eastward maximum of the mean zonal wind at z ˜ 100 km. Radar and lidar measurements at polar latitudes and results from other high-resolution global models are consistent with this finding. Hence, secondary gravity waves may play a significant role in the general circulation of the winter mesopause region.
NASA Technical Reports Server (NTRS)
Gregg, Watson W.; Busalacchi, Antonio (Technical Monitor)
2000-01-01
A coupled ocean general circulation, biogeochemical, and radiative model was constructed to evaluate and understand the nature of seasonal variability of chlorophyll and nutrients in the global oceans. Biogeochemical processes in the model are determined from the influences of circulation and turbulence dynamics, irradiance availability. and the interactions among three functional phytoplankton groups (diatoms. chlorophytes, and picoplankton) and three nutrients (nitrate, ammonium, and silicate). Basin scale (greater than 1000 km) model chlorophyll results are in overall agreement with CZCS pigments in many global regions. Seasonal variability observed in the CZCS is also represented in the model. Synoptic scale (100-1000 km) comparisons of imagery are generally in conformance although occasional departures are apparent. Model nitrate distributions agree with in situ data, including seasonal dynamics, except for the equatorial Atlantic. The overall agreement of the model with satellite and in situ data sources indicates that the model dynamics offer a reasonably realistic simulation of phytoplankton and nutrient dynamics on synoptic scales. This is especially true given that initial conditions are homogenous chlorophyll fields. The success of the model in producing a reasonable representation of chlorophyll and nutrient distributions and seasonal variability in the global oceans is attributed to the application of a generalized, processes-driven approach as opposed to regional parameterization and the existence of multiple phytoplankton groups with different physiological and physical properties. These factors enable the model to simultaneously represent many aspects of the great diversity of physical, biological, chemical, and radiative environments encountered in the global oceans.
Dark soliton pair of ultracold Fermi gases for a generalized Gross-Pitaevskii equation model.
Wang, Ying; Zhou, Yu; Zhou, Shuyu; Zhang, Yongsheng
2016-07-01
We present the theoretical investigation of dark soliton pair solutions for one-dimensional as well as three-dimensional generalized Gross-Pitaevskii equation (GGPE) which models the ultracold Fermi gas during Bardeen-Cooper-Schrieffer-Bose-Einstein condensates crossover. Without introducing any integrability constraint and via the self-similar approach, the three-dimensional solution of GGPE is derived based on the one-dimensional dark soliton pair solution, which is obtained through a modified F-expansion method combined with a coupled modulus-phase transformation technique. We discovered the oscillatory behavior of the dark soliton pair from the theoretical results obtained for the three-dimensional case. The calculated period agrees very well with the corresponding reported experimental result [Weller et al., Phys. Rev. Lett. 101, 130401 (2008)PRLTAO0031-900710.1103/PhysRevLett.101.130401], demonstrating the applicability of the theoretical treatment presented in this work.
Dinner at Orazio's--David Triggle the model of a mentor.
Smith, Susan L
2015-11-15
What does it mean to be a mentor in science? Definitions of mentorship are freely spouted in publications and include concepts such as academic support, professional development, role modeling, interaction, impartment of knowledge, evaluation of work, demonstration of methodology, etc. Perhaps most of us would agree with the duties listed. But just what does it mean, for example, to offer academic support? How might one facilitate professional development for a mentee? While we may agree to the general obligations of a mentor the specifics of what these entail would prove more controversial. This article will illustrate how easy it is to pick out a bad mentor. There are certain elements of conduct that, if practiced, undoubtedly put you in the "bad mentor" category. However, it is very difficult to explain just what it means to be not only an adequate mentor but also a stellar one. It may be easy to list the roles and responsibilities of a mentor but just how should they be performed/carried out? David Triggle is the model of an extraordinary mentor. The conclusion of this paper will focus on some specific mentorship activities David Triggle carried out that illustrate some of the intangible aspects of excellence in mentorship. Copyright © 2015 Elsevier Inc. All rights reserved.
Effect of the cosmological constant on halo size
NASA Astrophysics Data System (ADS)
Kulchoakrungsun, Ekapob; Lam, Adrian; Lowe, David A.
2018-04-01
In this work, we consider the effect of the cosmological constant on galactic halo size. As a model, we study the general relativistic derivation of orbits in the Schwarzschild-de Sitter metric. We find that there exists a length scale rΛ corresponding to a maximum size of a circular orbit of a test mass in a gravitationally bound system, which is the geometric mean of the cosmological horizon size squared and the Schwarzschild radius. This agrees well with the size of a galactic halo when the effects of dark matter are included. The size of larger structures such as galactic clusters and superclusters are also well-approximated by this scale. This model provides a simplified approach to computing the size of such structures without the usual detailed dynamical models. Some of the more detailed approaches that appear in the literature are reviewed, and we find the length scales agree to within a factor of order one. Finally, we note the length scale associated with the effects of MOND or Verlinde’s emergent gravity, which offer explanations of the flattening of galaxy rotation curves without invoking dark matter, may be expressed as the geometric mean of the cosmological horizon size and the Schwarzschild radius, which is typically 100 times smaller than rΛ.
Hoarea, Karen J; Millsc, Jane; Francis, Karen
2013-01-01
Graduate nurses in general practice became a feature of New Zealand's health care system in 2008 following an expansion of the New Entrant to Practice Programme. General practice in New Zealand comprises general practitioner business owners who employ nursing and administration staff. Practice nurses are an ageing workforce in New Zealand, it is imperative therefore to attract younger nurses into general practice. This paper reports a section of the findings from a constructivist grounded theory study which examines the use of information by practice nurses in New Zealand. Initially data were collected using the ethnographic technique of observation and field notations in one general practice. Theoretical sensitivity to the value of role models was heightened by this first phase of data collection. A total of eleven practice nurses were interviewed from six general practices. One practice nurse agreed to a second interview; five of the interviewees were new graduate nurses and the other six were experienced practice nurses. The grounded theory constructed from this research was reciprocal role modelling which comprises the following three categories, becoming willing, realising potential and becoming a better practitioner. Graduate nurses and experienced practice nurses enter into a relationship of reciprocal role modelling. Becoming willing, the first core category of this grounded theory features three sub-categories: building respectful relationships, proving yourself and discerning decision making which are reported in this paper. Findings from this study may address the reported phenomenon of 'transition shock' of newly graduated nurses in the work place.
A survey of psychiatrists' attitudes toward treatment guidelines.
Healy, Daniel J; Goldman, Mona; Florence, Timothy; Milner, Karen K
2004-04-01
We developed a survey to look at psychiatrists' attitudes toward psychotropic prescribing guidelines, specifically the Texas Medication Algorithm Project (TMAP) algorithms. The 22-page survey was distributed to 24 psychiatrists working in 4 CMHC's; 13 completed the survey. 90% agreed that guidelines should be general and flexible. The majority also agreed that guidelines should define how to measure response to a specific agent; fewer agreed guidelines should specify dosage, side effect management, or augmentation strategies. Psychiatrists were familiar with TMAP; none referred to it in their practice. In spite of this, psychiatrists' medication preferences were similar to those suggested by guidelines.
Estimation of soil hydraulic properties with microwave techniques
NASA Technical Reports Server (NTRS)
Oneill, P. E.; Gurney, R. J.; Camillo, P. J.
1985-01-01
Useful quantitative information about soil properties may be obtained by calibrating energy and moisture balance models with remotely sensed data. A soil physics model solves heat and moisture flux equations in the soil profile and is driven by the surface energy balance. Model generated surface temperature and soil moisture and temperature profiles are then used in a microwave emission model to predict the soil brightness temperature. The model hydraulic parameters are varied until the predicted temperatures agree with the remotely sensed values. This method is used to estimate values for saturated hydraulic conductivity, saturated matrix potential, and a soil texture parameter. The conductivity agreed well with a value measured with an infiltration ring and the other parameters agreed with values in the literature.
NASA Astrophysics Data System (ADS)
Wu, M. Q.; Pan, C. K.; Chan, V. S.; Li, G. Q.; Garofalo, A. M.; Jian, X.; Liu, L.; Ren, Q. L.; Chen, J. L.; Gao, X.; Gong, X. Z.; Ding, S. Y.; Qian, J. P.; Cfetr Physics Team
2018-04-01
Time-dependent integrated modeling of DIII-D ITER-like and high bootstrap current plasma ramp-up discharges has been performed with the equilibrium code EFIT, and the transport codes TGYRO and ONETWO. Electron and ion temperature profiles are simulated by TGYRO with the TGLF (SAT0 or VX model) turbulent and NEO neoclassical transport models. The VX model is a new empirical extension of the TGLF turbulent model [Jian et al., Nucl. Fusion 58, 016011 (2018)], which captures the physics of multi-scale interaction between low-k and high-k turbulence from nonlinear gyro-kinetic simulation. This model is demonstrated to accurately model low Ip discharges from the EAST tokamak. Time evolution of the plasma current density profile is simulated by ONETWO with the experimental current ramp-up rate. The general trend of the predicted evolution of the current density profile is consistent with that obtained from the equilibrium reconstruction with Motional Stark effect constraints. The predicted evolution of βN , li , and βP also agrees well with the experiments. For the ITER-like cases, the predicted electron and ion temperature profiles using TGLF_Sat0 agree closely with the experimental measured profiles, and are demonstrably better than other proposed transport models. For the high bootstrap current case, the predicted electron and ion temperature profiles perform better in the VX model. It is found that the SAT0 model works well at high IP (>0.76 MA) while the VX model covers a wider range of plasma current ( IP > 0.6 MA). The results reported in this paper suggest that the developed integrated modeling could be a candidate for ITER and CFETR ramp-up engineering design modeling.
Radial restricted solid-on-solid and etching interface-growth models
NASA Astrophysics Data System (ADS)
Alves, Sidiney G.
2018-03-01
An approach to generate radial interfaces is presented. A radial network recursively obtained is used to implement discrete model rules designed originally for the investigation in flat substrates. I used the restricted solid-on-solid and etching models as to test the proposed scheme. The results indicate the Kardar, Parisi, and Zhang conjecture is completely verified leading to a good agreement between the interface radius fluctuation distribution and the Gaussian unitary ensemble. The evolution of the radius agrees well with the generalized conjecture, and the two-point correlation function exhibits also a good agreement with the covariance of the Airy2 process. The approach can be used to investigate radial interfaces evolution for many other classes of universality.
Radial restricted solid-on-solid and etching interface-growth models.
Alves, Sidiney G
2018-03-01
An approach to generate radial interfaces is presented. A radial network recursively obtained is used to implement discrete model rules designed originally for the investigation in flat substrates. I used the restricted solid-on-solid and etching models as to test the proposed scheme. The results indicate the Kardar, Parisi, and Zhang conjecture is completely verified leading to a good agreement between the interface radius fluctuation distribution and the Gaussian unitary ensemble. The evolution of the radius agrees well with the generalized conjecture, and the two-point correlation function exhibits also a good agreement with the covariance of the Airy_{2} process. The approach can be used to investigate radial interfaces evolution for many other classes of universality.
14 CFR 91.309 - Towing: Gliders and unpowered ultralight vehicles.
Code of Federal Regulations, 2010 CFR
2010-01-01
... vehicle have agreed upon a general course of action, including takeoff and release signals, airspeeds, and... vehicles. 91.309 Section 91.309 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Special...
Kinetic models for historical processes of fast invasion and aggression
NASA Astrophysics Data System (ADS)
Aristov, Vladimir V.; Ilyin, Oleg V.
2015-04-01
In the last few decades many investigations have been devoted to theoretical models in new areas concerning description of different biological, sociological, and historical processes. In the present paper we suggest a model of the Nazi Germany invasion of Poland, France, and the USSR based on kinetic theory. We simulate this process with the Cauchy boundary problem for two-element kinetic equations. The solution of the problem is given in the form of a traveling wave. The propagation velocity of a front line depends on the quotient between initial forces concentrations. Moreover it is obtained that the general solution of the model can be expressed in terms of quadratures and elementary functions. Finally it is shown that the front-line velocities agree with the historical data.
Generating target system specifications from a domain model using CLIPS
NASA Technical Reports Server (NTRS)
Sugumaran, Vijayan; Gomaa, Hassan; Kerschberg, Larry
1991-01-01
The quest for reuse in software engineering is still being pursued and researchers are actively investigating the domain modeling approach to software construction. There are several domain modeling efforts reported in the literature and they all agree that the components that are generated from domain modeling are more conducive to reuse. Once a domain model is created, several target systems can be generated by tailoring the domain model or by evolving the domain model and then tailoring it according to the specified requirements. This paper presents the Evolutionary Domain Life Cycle (EDLC) paradigm in which a domain model is created using multiple views, namely, aggregation hierarchy, generalization/specialization hierarchies, object communication diagrams and state transition diagrams. The architecture of the Knowledge Based Requirements Elicitation Tool (KBRET) which is used to generate target system specifications is also presented. The preliminary version of KBRET is implemented in the C Language Integrated Production System (CLIPS).
Steil, Garry M; Hipszer, Brian; Reifman, Jaques
2010-05-01
One year after its initial meeting, the Glycemia Modeling Working Group reconvened during the 2009 Diabetes Technology Meeting in San Francisco, CA. The discussion, involving 39 scientists, again focused on the need for individual investigators to have access to the clinical data required to develop and refine models of glucose metabolism, the need to understand the differences among the distinct models and control algorithms, and the significance of day-to-day subject variability. The key conclusion was that model-based comparisons of different control algorithms, or the models themselves, are limited by the inability to access individual model-patient parameters. It was widely agreed that these parameters, as opposed to the average parameters that are typically reported, are necessary to perform such comparisons. However, the prevailing view was that, if investigators were to make the parameters available, it would limit their ability (and that of their institution) to benefit from the invested work in developing their models. A general agreement was reached regarding the importance of each model having an insulin pharmacokinetic/pharmacodynamic profile that is not different from profiles reported in the literature (88% of the respondents agreed that the model should have similar curves or be analyzed separately) and the importance of capturing intraday variance in insulin sensitivity (91% of the respondents indicated that this could result in changes in fasting glucose of >or=15%, with 52% of the respondents believing that the variability could effect changes of >or=30%). Seventy-six percent of the participants indicated that high-fat meals were thought to effect changes in other model parameters in addition to gastric emptying. There was also widespread consensus as to how a closed-loop controller should respond to day-to-day changes in model parameters (with 76% of the participants indicating that fasting glucose should be within 15% of target, with 30% of the participants believing that it should be at target). The group was evenly divided as to whether the glucose sensor per se continues to be the major obstacle in achieving closed-loop control. Finally, virtually all participants agreed that a future two-day workshop should be organized to compare, contrast, and understand the differences among the different models and control algorithms. (c) 2010 Diabetes Technology Society.
Ehrlich, Matthias; Schüffny, René
2013-01-01
One of the major outcomes of neuroscientific research are models of Neural Network Structures (NNSs). Descriptions of these models usually consist of a non-standardized mixture of text, figures, and other means of visual information communication in print media. However, as neuroscience is an interdisciplinary domain by nature, a standardized way of consistently representing models of NNSs is required. While generic descriptions of such models in textual form have recently been developed, a formalized way of schematically expressing them does not exist to date. Hence, in this paper we present Neural Schematics as a concept inspired by similar approaches from other disciplines for a generic two dimensional representation of said structures. After introducing NNSs in general, a set of current visualizations of models of NNSs is reviewed and analyzed for what information they convey and how their elements are rendered. This analysis then allows for the definition of general items and symbols to consistently represent these models as Neural Schematics on a two dimensional plane. We will illustrate the possibilities an agreed upon standard can yield on sampled diagrams transformed into Neural Schematics and an example application for the design and modeling of large-scale NNSs.
A Bone Marrow Aspirate and Trephine Simulator.
Yap, Eng Soo; Koh, Pei Lin; Ng, Chin Hin; de Mel, Sanjay; Chee, Yen Lin
2015-08-01
Bone marrow aspirate and trephine (BMAT) biopsy is a commonly performed procedure in hematology-oncology practice. Although complications are uncommon, they can cause significant morbidity and mortality. Simulation models are an excellent tool to teach novice doctors basic procedural skills before performing the actual procedure on patients to improve patient safety and well-being. There are no commercial BMAT simulators, and this technical report describes the rationale, technical specifications, and construction of a low-cost, easily constructed, reusable BMAT simulator that reproduced the tactile properties of tissue layers for use as a teaching tool in our resident BMAT simulation course. Preliminary data of learner responses to the simulator were also collected. From April 2013 to November 2013, 32 internal medicine residents underwent the BMAT simulation course. Eighteen (56%) completed the online survey, 11 residents with previous experience doing BMAT and 7 without experience. Despite the difference in operative experience, both experienced and novice residents all agreed or strongly agreed that the model aided their understanding of the BMAT procedure. All agreed or strongly agreed that this enhanced their knowledge of anatomy and 16 residents (89%) agreed or strongly agreed that this model was a realistic simulator. We present a novel, low-cost, easily constructed, realistic BMAT simulator for training novice doctors to perform BMAT.
Detailed interpretation of aeromagnetic data from the Patagonia Mountains area, southeastern Arizona
Bultman, Mark W.
2015-01-01
Euler deconvolution depth estimates derived from aeromagnetic data with a structural index of 0 show that mapped faults on the northern margin of the Patagonia Mountains generally agree with the depth estimates in the new geologic model. The deconvolution depth estimates also show that the concealed Patagonia Fault southwest of the Patagonia Mountains is more complex than recent geologic mapping represents. Additionally, Euler deconvolution depth estimates with a structural index of 2 locate many potential intrusive bodies that might be associated with known and unknown mineralization.
Calculation of wind-driven surface currents in the North Atlantic Ocean
NASA Technical Reports Server (NTRS)
Rees, T. H.; Turner, R. E.
1976-01-01
Calculations to simulate the wind driven near surface currents of the North Atlantic Ocean are described. The primitive equations were integrated on a finite difference grid with a horizontal resolution of 2.5 deg in longitude and latitude. The model ocean was homogeneous with a uniform depth of 100 m and with five levels in the vertical direction. A form of the rigid-lid approximation was applied. Generally, the computed surface current patterns agreed with observed currents. The development of a subsurface equatorial countercurrent was observed.
Preliminary Support for a Generalized Arousal Model of Political Conservatism
Tritt, Shona M.; Inzlicht, Michael; Peterson, Jordan B.
2013-01-01
It is widely held that negative emotions such as threat, anxiety, and disgust represent the core psychological factors that enhance conservative political beliefs. We put forward an alternative hypothesis: that conservatism is fundamentally motivated by arousal, and that, in this context, the effect of negative emotion is due to engaging intensely arousing states. Here we show that study participants agreed more with right but not left-wing political speeches after being exposed to positive as well as negative emotion-inducing film-clips. No such effect emerged for neutral-content videos. A follow-up study replicated and extended this effect. These results are consistent with the idea that emotional arousal, in general, and not negative valence, specifically, may underlie political conservatism. PMID:24376687
New two-metric theory of gravity with prior geometry
NASA Technical Reports Server (NTRS)
Lightman, A. P.; Lee, D. L.
1973-01-01
A Lagrangian-based metric theory of gravity is developed with three adjustable constants and two tensor fields, one of which is a nondynamic 'flat space metric' eta. With a suitable cosmological model and a particular choice of the constants, the 'post-Newtonian limit' of the theory agrees, in the current epoch, with that of general relativity theory (GRT); consequently the theory is consistent with current gravitation experiments. Because of the role of eta, the gravitational 'constant' G is time-dependent and gravitational waves travel null geodesics of eta rather than the physical metric g. Gravitational waves possess six degrees of freedom. The general exact static spherically-symmetric solution is a four-parameter family. Future experimental tests of the theory are discussed.
Preliminary support for a generalized arousal model of political conservatism.
Tritt, Shona M; Inzlicht, Michael; Peterson, Jordan B
2013-01-01
It is widely held that negative emotions such as threat, anxiety, and disgust represent the core psychological factors that enhance conservative political beliefs. We put forward an alternative hypothesis: that conservatism is fundamentally motivated by arousal, and that, in this context, the effect of negative emotion is due to engaging intensely arousing states. Here we show that study participants agreed more with right but not left-wing political speeches after being exposed to positive as well as negative emotion-inducing film-clips. No such effect emerged for neutral-content videos. A follow-up study replicated and extended this effect. These results are consistent with the idea that emotional arousal, in general, and not negative valence, specifically, may underlie political conservatism.
Herschel/SPIRE observations of water production rates and ortho-to-para ratios in comets★
NASA Astrophysics Data System (ADS)
Wilson, Thomas G.; Rawlings, Jonathan M. C.; Swinyard, Bruce M.
2017-04-01
This paper presents Herschel/SPIRE (Spectral and Photometric Imaging Receiver) spectroscopic observations of several fundamental rotational ortho- and para-water transitions seen in three Jupiter-family comets and one Oort-cloud comet. Radiative transfer models that include excitation by collisions with neutrals and electrons, and by solar infrared radiation, were used to produce synthetic emission line profiles originating in the cometary coma. Ortho-to-para ratios (OPRs) were determined and used to derived water production rates for all comets. Comparisons are made with the water production rates derived using an OPR of 3. The OPR of three of the comets in this study is much lower than the statistical equilibrium value of 3; however they agree with observations of comets 1P/Halley and C/2001 A2 (LINEAR), and the protoplanetary disc TW Hydrae. These results provide evidence suggesting that OPR variation is caused by post-sublimation gas-phase nuclear-spin conversion processes. The water production rates of all comets agree with previous work and, in general, decrease with increasing nucleocentric offset. This could be due to a temperature profile, additional water source or OPR variation in the comae, or model inaccuracies.
Wu, Robert; Lo, Vivian; Morra, Dante; Appel, Eva; Arany, Teri; Curiale, Beth; Ryan, Joanne; Quan, Sherman
2015-02-01
There is increasing interest in the use of information and communication technologies to improve how clinicians communicate in hospital settings. We implemented a communication system with support for physician handover and secure messaging on 2 general internal medicine wards. We measured usage and surveyed physicians and nurses on perceptions of the system's effects on communication. Between May 2011 and August 2012, a clinical teaching team received, on average, 14.8 messages per day through the system. Messages were typically sent as urgent (69.1%) and requested a text reply (76.5%). For messages requesting a text reply, 8.6% did not receive a reply. For those messages that did receive a reply, the median response time was 2.3 minutes, and 84.5% of messages received a reply within 15 minutes. Of those who completed the survey, 95.3% were medical residents (82 of 86) and 81.7% were nurses (83 of 116). Medical trainees (82.8%) and nursing staff (78.3%) agreed or strongly agreed that the system helped to speed up their daily work tasks. Overall, 67.1% of the trainees and 73.2% of nurses agreed or strongly agreed that the system made them more accountable in their clinical roles. Only 35.8% of physicians and 26.3% of nurses agreed or strongly agreed that the system was useful for communicating complex issues. In summary, with a system designed to improve communication, we found that there was high uptake and that users perceived that the system improved efficiency and accountability but was not appropriate for communicating complex issues. © 2014 Society of Hospital Medicine.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Do other Federal agencies know if the Office of National Drug Control Policy agrees to a voluntary exclusion? 1404.645 Section 1404.645 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) General Principles Relating to Suspension and...
NASA Astrophysics Data System (ADS)
Sznajd-Weron, Katarzyna; Weron, Rafał; Włoszczowska, Maja
2008-11-01
In this paper we introduce two models of opinion dynamics in oligopoly markets and apply them to a situation where a new entrant challenges two incumbents of the same size. The models differ in the way in which the two forces influencing consumer choice—(local) social interactions and (global) advertising—interact. We study the general behavior of the models using the mean field approach and Monte Carlo simulations and calibrate the models using data from the Polish telecommunications market. For one of the models criticality is observed—below a certain critical level of advertising the market approaches a lock-in situation, where one market leader dominates the market and all other brands disappear. Interestingly, for both models the best fits to real data are obtained for conformity level p \\in (0.3,0.4) . This agrees very well with the conformity level found by Solomon Asch in his famous social experiment.
Quantitative Study on Corrosion of Steel Strands Based on Self-Magnetic Flux Leakage.
Xia, Runchuan; Zhou, Jianting; Zhang, Hong; Liao, Leng; Zhao, Ruiqiang; Zhang, Zeyu
2018-05-02
This paper proposed a new computing method to quantitatively and non-destructively determine the corrosion of steel strands by analyzing the self-magnetic flux leakage (SMFL) signals from them. The magnetic dipole model and three growth models (Logistic model, Exponential model, and Linear model) were proposed to theoretically analyze the characteristic value of SMFL. Then, the experimental study on the corrosion detection by the magnetic sensor was carried out. The setup of the magnetic scanning device and signal collection method were also introduced. The results show that the Logistic Growth model is verified as the optimal model for calculating the magnetic field with good fitting effects. Combined with the experimental data analysis, the amplitudes of the calculated values ( B xL ( x,z ) curves) agree with the measured values in general. This method provides significant application prospects for the evaluation of the corrosion and the residual bearing capacity of steel strand.
Local sensitivities of the gulf stream separation
Schoonover, Joseph; Dewar, William K.; Wienders, Nicolas; ...
2016-12-05
Robust and accurate Gulf Stream separation remains an unsolved problem in general circulation modeling whose resolution will positively impact the ocean and climate modeling communities. Oceanographic literature does not face a shortage of plausible hypotheses that attempt to explain the dynamics of the Gulf Stream separation, yet a single theory that the community agrees on is missing. We investigate the impact of the Deep Western Boundary Current, coastline curvature, and continental shelf steepening on the Gulf Stream separation within regional configurations of the MIT General Circulation Model. Artificial modifications to the regional bathymetry are introduced to investigate the sensitivity ofmore » the separation to each of these factors. Metrics for subsurface separation detection confirm the direct link between flow separation and the surface expression of the Gulf Stream in the Mid-Atlantic Bight. Conversely, the Gulf Stream separation exhibits minimal sensitivity to the presence of the DWBC and coastline curvature. The implications of these results to the development of a “separation recipe” for ocean modeling are discussed. Furthermore, we conclude adequate topographic resolution is a necessary, but not sufficient, condition for proper Gulf Stream separation.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schoonover, Joseph; Dewar, William K.; Wienders, Nicolas
Robust and accurate Gulf Stream separation remains an unsolved problem in general circulation modeling whose resolution will positively impact the ocean and climate modeling communities. Oceanographic literature does not face a shortage of plausible hypotheses that attempt to explain the dynamics of the Gulf Stream separation, yet a single theory that the community agrees on is missing. We investigate the impact of the Deep Western Boundary Current, coastline curvature, and continental shelf steepening on the Gulf Stream separation within regional configurations of the MIT General Circulation Model. Artificial modifications to the regional bathymetry are introduced to investigate the sensitivity ofmore » the separation to each of these factors. Metrics for subsurface separation detection confirm the direct link between flow separation and the surface expression of the Gulf Stream in the Mid-Atlantic Bight. Conversely, the Gulf Stream separation exhibits minimal sensitivity to the presence of the DWBC and coastline curvature. The implications of these results to the development of a “separation recipe” for ocean modeling are discussed. Furthermore, we conclude adequate topographic resolution is a necessary, but not sufficient, condition for proper Gulf Stream separation.« less
Analysis of the physical state of one Arctic polar stratospheric cloud based on observations
NASA Technical Reports Server (NTRS)
Drdla, K.; Tabazadeh, A.; Turco, R. P.; Jacobson, M. Z.; Dye, J. E.; Twohy, C.; Baumgardner, D.
1994-01-01
During the Arctic Airborne Stratospheric Expedition (AASE) simultaneous measurements of aerosol size distribution and NO(y)(HN03 + NO + NO2 + 2(N205)) were made along ER-2 flight paths. The flow characteristics of the NO(y) instrument allow us to derive the condensed NO(y) amount (assumed to be HN03) present during polar stratospheric cloud (PSC) events. Analysis of the January 24th flight indicates that this condensed HN03 amount does not agree well with the aerosol volume if the observed PSCs are composed of solid nitric acid trihydrate (NAT), as is generally assumed. However, the composition agrees well with that predicted for liquid H2S04/HN03/H20 solution droplets using a new Aerosol Physical Chemistry Model (APCM). The agreement corresponds in detail to variations in temperature and humidity. The weight percentages of H2SO4, HN03, and H2O derived from the measurements all correspond to those predicted for ternary, liquid solutions.
NASA Astrophysics Data System (ADS)
Zhang, Yu-Yu; Chen, Xiang-You
2017-12-01
An unexplored nonperturbative deep strong coupling (npDSC) achieved in superconducting circuits has been studied in the anisotropic Rabi model by the generalized squeezing rotating-wave approximation. Energy levels are evaluated analytically from the reformulated Hamiltonian and agree well with numerical ones in a wide range of coupling strength. Such improvement ascribes to deformation effects in the displaced-squeezed state presented by the squeezed momentum variance, which are omitted in previous displaced states. The atom population dynamics confirms the validity of our approach for the npDSC strength. Our approach offers the possibility to explore interesting phenomena analytically in the npDSC regime in qubit-oscillator experiments.
Modelling biological invasions: species traits, species interactions, and habitat heterogeneity.
Cannas, Sergio A; Marco, Diana E; Páez, Sergio A
2003-05-01
In this paper we explore the integration of different factors to understand, predict and control ecological invasions, through a general cellular automaton model especially developed. The model includes life history traits of several species in a modular structure interacting multiple cellular automata. We performed simulations using field values corresponding to the exotic Gleditsia triacanthos and native co-dominant trees in a montane area. Presence of G. triacanthos juvenile bank was a determinant condition for invasion success. Main parameters influencing invasion velocity were mean seed dispersal distance and minimum reproductive age. Seed production had a small influence on the invasion velocity. Velocities predicted by the model agreed well with estimations from field data. Values of population density predicted matched field values closely. The modular structure of the model, the explicit interaction between the invader and the native species, and the simplicity of parameters and transition rules are novel features of the model.
13 CFR 500.205 - Application process.
Code of Federal Regulations, 2013 CFR
2013-01-01
... Program, as described in the Loan Documents, and agreeing to permit audits by the General Accounting... consistent with the “Uniform Standards of Professional Appraisal Practice,” promulgated by the Appraisal... financial statements reviewed by a certified public accountant following generally accepted accounting...
13 CFR 500.205 - Application process.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Program, as described in the Loan Documents, and agreeing to permit audits by the General Accounting... consistent with the “Uniform Standards of Professional Appraisal Practice,” promulgated by the Appraisal... financial statements reviewed by a certified public accountant following generally accepted accounting...
13 CFR 500.205 - Application process.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Program, as described in the Loan Documents, and agreeing to permit audits by the General Accounting... consistent with the “Uniform Standards of Professional Appraisal Practice,” promulgated by the Appraisal... financial statements reviewed by a certified public accountant following generally accepted accounting...
13 CFR 500.205 - Application process.
Code of Federal Regulations, 2012 CFR
2012-01-01
... Program, as described in the Loan Documents, and agreeing to permit audits by the General Accounting... consistent with the “Uniform Standards of Professional Appraisal Practice,” promulgated by the Appraisal... financial statements reviewed by a certified public accountant following generally accepted accounting...
19 CFR 10.550 - Verification and justification of claim for preferential treatment.
Code of Federal Regulations, 2010 CFR
2010-04-01
... may agree. (b) Applicable accounting principles. When conducting a verification of origin to which Generally Accepted Accounting Principles may be relevant, CBP will apply and accept the Generally Accepted Accounting Principles applicable in the country of production. ...
Higher professional education for general practitioners: postal questionnaire survey.
Smith, L F; Eve, R; Crabtree, R
2000-04-01
There is no consensus about whether higher professional education (HPE) is necessary for general practitioners (GPs) to complete their vocational training. To investigate beliefs about the need for HPE, its funding, duration, curriculum, and whether new principals (NPs) are eligible to undertake it. A confidential postal questionnaire was sent to senior partners, GP registrars, NPs, GP trainers, and GP tutors, principally in the old South West region of England, and nationally to other 'academic' GPs. Of 1199 GPs, 750 (62.6%) replied; 561 (79.2%) responders agreed with the principle of HPE for NPs, especially members of the Royal College of General Practitioners and academic GPs; senior partners (SPs) were less likely to agree (all P < 0.001). Of 700 GPs, 331 (50.3%) believed that HPE should last one or two years, 66.4% agreed that NPs should have a major input into the HPE curriculum, and 54.6% agreed that health authorities should be major sources of funding, together with the postgraduate deans (29.9%). GP tutors and trainers should have the main responsibility for teaching HPE. The principal barriers to setting up a HPE course are the financial cost, the time cost, difficulty in changing the status quo, and various practical problems. The facilitatory influences are: the enthusiasm of the NPs and of their clinical colleagues, an appropriate educational environment, a high quality clinical base, and recognition that NPs have specific needs. Of 668 GPs, 89.7% would release NPs if an HPE course were free and locums were paid, although SPs were less likely to agree (P < 0.001); if the HPE course cost the practice money, then only 30.6% would release NPs. If adequately externally funded, then there is widespread support for HPE with most GPs willing to release NPs. NPs and existing GP teachers should decide the curriculum. Its aim should be to provide educational support for NPs during the transition from GP registrar to fully-trained GP principal.
Solute effect on basal and prismatic slip systems of Mg.
Moitra, Amitava; Kim, Seong-Gon; Horstemeyer, M F
2014-11-05
In an effort to design novel magnesium (Mg) alloys with high ductility, we present a first principles data based on the Density Functional Theory (DFT). The DFT was employed to calculate the generalized stacking fault energy curves, which can be used in the generalized Peierls-Nabarro (PN) model to study the energetics of basal slip and prismatic slip in Mg with and without solutes to calculate continuum scale dislocation core widths, stacking fault widths and Peierls stresses. The generalized stacking fault energy curves for pure Mg agreed well with other DFT calculations. Solute effects on these curves were calculated for nine alloying elements, namely Al, Ca, Ce, Gd, Li, Si, Sn, Zn and Zr, which allowed the strength and ductility to be qualitatively estimated based on the basal dislocation properties. Based on our multiscale methodology, a suggestion has been made to improve Mg formability.
A generalized theory for eccentric and misalignment effects in high-pressure annular seals
NASA Technical Reports Server (NTRS)
Chen, W. C.; Jackson, E. D.
1986-01-01
High-pressure annular seal leakage and dynamic coefficients vary with eccentricity and misalignment. Recent seal leakage data with both concentric and fully eccentric alignments support the seal leakage model with surface roughness and eccentricity effects included. In this paper, the seal dynamic coefficient calculation has been generalized and allows direct calculation of the seal dynamic coefficients at any circumferential location. The generalized solution agrees with the results obtained by using the calculated values of an earlier paper and performing a coordinate transformation. The analysis results coincide with the measured data in showing that the stiffness and damping matrices of seal coefficients are not skew symmetric, and the main diagonal seal coefficients are not equal. The measured direct stiffnesses were found higher than predicted by the concentric seal theory, but this may be explained by the presence of eccentricity in the test operating mode.
Krajewski, Aleksandra; Filippa, Dawn; Staff, Ilene; Singh, Rekha; Kirton, Orlando C
2013-08-01
Today's general surgery interns are faced with increased duty hour restrictions and stringent competency-based supervision milestone requirements (ie, from direct to indirect supervision). Working within these constraints, we instituted a unique 2-month intern curriculum (boot camp) incorporating knowledge-based, experiential, and practical components. To describe our curriculum and the effect on resident performance and teaching faculty and nursing staff perceptions. All interns underwent a 2-month (July and August 2011) boot camp curriculum consisting of two 2½-hour knowledge-based and procedural skills (SimMan) didactic sessions per week and completion of 25 core intensive introductory American College of Surgeons Fundamentals of Surgery web-based self-study modules, followed by a standardized patient clinical skills assessment. Integrated general surgery residency program at the University of Connecticut School of Medicine, Farmington. Postgraduate year 1 general surgery categorical and preliminary residents. We used several assessment tools, including an intern boot camp survey, clinical skills assessment scores, intern American Board of Surgeons In-Training Examination scores, and nursing staff and teaching faculty surveys of intern performance and aptitudes compared with the previous year's interns. Data were analyzed by independent group t test, χ2 tests of proportions, and Fisher exact test for small sample cross tables. In total, 84% (91 of 108) of intern respondents agreed or strongly agreed with the usefulness, relevance, and execution of the boot camp. Compared with the previous year's interns, the nursing staff agreed or strongly agreed that the cohort interns were better at patient assessment, collaboration, and effective communication and provided compassionate and respectful patient care. More than 40% (7 of 17) of surveyed teaching faculty agreed or strongly agreed that the cohort interns demonstrated better patient care and procedural skills and self-confidence compared with the previous year's interns. The clinical skills assessment scores after the 2-month boot camp paralleled the scores typically seen at the end of the previous 2 internship years (P > .25 for all). The proportion of nondesignated and categorical interns pursuing careers in general surgery scoring in the top quartile on the American Board of Surgery In-Training Examination increased from 7% (2 of 28) to 50% (5 of 10) compared with the previous 2 internship years (P = .01). Recent changes in intern duty hours and supervision rules mandate that residency training programs must institute a competency-oriented curriculum to provide interns with the necessary knowledge and practical skills to attain clinical competence.
Bifurcation and stability in a model of moist convection in a shearing environment
NASA Technical Reports Server (NTRS)
Shirer, H. N.
1980-01-01
The truncated spectral system (model I) of shallow moist two-dimensional convection discussed by Shirer and Dutton (1979) is expanded to eleven coefficients (model II) in order to include a basic wind. Cloud streets, the atmospheric analog of the solutions to model II, are typically observed in an environment containing a shearing basic motion field. Analysis of the branching behavior of solutions to mode II shows that, if the basic wind direction varies with height, very complex temporal behavior is possible as the modified Rayleigh number HR is increased sufficiently. The first convective solution is periodic, corresponding to a cloud band that propagates downwind; but secondary branching to a two-dimensional torus can occur for larger values of HR. Orientation band formulas are derived whose predictions generally agree with the results of previous studies.
NASA Astrophysics Data System (ADS)
Kinsey, J. E.; Waltz, R. E.; DeBoo, J. C.
1999-05-01
It is difficult to discriminate between various tokamak transport models using standardized statistical measures to assess the goodness of fit with steady-state density and temperature profiles in tokamaks. This motivates consideration of transient transport experiments as a technique for testing the temporal response predicted by models. Results are presented comparing the predictions from the Institute for Fusion Studies—Princeton Plasma Physics Laboratory (IFS/PPPL), gyro-Landau-fluid (GLF23), Multi-mode (MM), Current Diffusive Ballooning Mode (CDBM), and Mixed-shear (MS) transport models against data from ohmic cold pulse and modulated electron cyclotron heating (ECH) experiments. In ohmically heated discharges with rapid edge cooling due to trace impurity injection, it is found that critical gradient models containing a strong temperature ratio (Ti/Te) dependence can exhibit behavior that is qualitatively consistent both spatially and temporally with experimental observation while depending solely on local parameters. On the DIII-D tokamak [J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)], off-axis modulated ECH experiments have been conducted in L-mode (low confinement mode) and the perturbed electron and ion temperature response to multiple heat pulses has been measured across the plasma core. Comparing the predicted Fourier phase of the temperature perturbations, it is found that no single model yielded agreement with both electron and ion phases for all cases. In general, it was found that the IFS/PPPL, GLF23, and MS models agreed well with the ion response, but not with the electron response. The CDBM and MM models agreed well with the electron response, but not with the ion response. For both types of transient experiments, temperature coupling between the electron and ion transport is found to be an essential feature needed in the models for reproducing the observed perturbative response.
A Tour Through Shape Dynamic Black Holes
NASA Astrophysics Data System (ADS)
Herczeg, Gabriel
Shape dynamics is a classical theory of gravity which agrees with general relativity in many important cases, but possesses different gauge symmetries and constraints. Rather than spacetime diffeomorphism invariance, shape dynamics takes spatial diffeomorphism invariance and spatial Weyl invariance as the fundamental gauge symmetries associated with the gravitational field. Despite these differences, shape dynamics and general relativity generically predict the same dynamics--there exist gauge-fixings of each theory that ensure agreement with the other. However, these gauge-fixing conditions are not necessarily globally well-defined and it is therefore possible to find solutions of the shape dynamics equations of motion that agree with general relativity on some open neighborhoods, but which have different global structures. In particular, the black hole solutions of the two theories disagree globally. Understanding these novel "shape dynamic black holes" is the primary goal of this thesis.
Observational constraints on extended Chaplygin gas cosmologies
NASA Astrophysics Data System (ADS)
Paul, B. C.; Thakur, P.; Saha, A.
2017-08-01
We investigate cosmological models with extended Chaplygin gas (ECG) as a candidate for dark energy and determine the equation of state parameters using observed data namely, observed Hubble data, baryon acoustic oscillation data and cosmic microwave background shift data. Cosmological models are investigated considering cosmic fluid which is an extension of Chaplygin gas, however, it reduces to modified Chaplygin gas (MCG) and also to generalized Chaplygin gas (GCG) in special cases. It is found that in the case of MCG and GCG, the best-fit values of all the parameters are positive. The distance modulus agrees quite well with the experimental Union2 data. The speed of sound obtained in the model is small, necessary for structure formation. We also determine the observational constraints on the constants of the ECG equation.
This is the enforcement alert for U.S. EPA Encourages Iron and Steel Minimills to Self Audits to Address Noncompliance with Environmental Requirements; Nucor Corp. agrees to Control Practices; Provides Model for Industry
NASA Technical Reports Server (NTRS)
Cronkhite, J. D.; Berry, V. L.; Dompka, R. V.
1987-01-01
The AH-1G NASTRAN finite element model (FEM) is described and the correlations with measured data that were conducted to verify the model are summarized. Comparisons of the AH-1G NASTRAN FEM calculations with measured data include the following: (1) fuselage and tailboom static load deflection (stiffness) testing, (2) airframe ground vibration testing (0-30 H<), (3) airframe flight vibration testing (main rotor, 2,4, and 6/rev), and (4) tailboom effective skin static testing. A description of the modeling rationale and techniques used to develop the NASTRAN FEM is presented in conjunction with all previous correlation work. In general, the correlations show good agreement between analysis and test in stiffness and vibration response through 15 to 20 Hz. For higher frequencies (equal to or greater than 4/rev (21.6 Hz)), the vibration responses generally did not agree well. Also, the lateral (2/rev (10.8 Hz)) flight vibration responses were much lower in the FEM than test, indicating that there is a significant excitation source other than at the main rotor hub that is affecting the lateral vibrations, such as downwash impingement on the vertical tail.
21 CFR 10.60 - Referral by court.
Code of Federal Regulations, 2010 CFR
2010-04-01
... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATIVE PRACTICES AND PROCEDURES General Administrative Procedures § 10.60 Referral by court. (a) This section... resources, the Commissioner shall agree to accept a referral and shall proceed to determine the matter...
Bounds on quantum collapse models from matter-wave interferometry: calculational details
NASA Astrophysics Data System (ADS)
Toroš, Marko; Bassi, Angelo
2018-03-01
We present a simple derivation of the interference pattern in matter-wave interferometry predicted by a class of quantum master equations. We apply the obtained formulae to the following collapse models: the Ghirardi-Rimini-Weber (GRW) model, the continuous spontaneous localization (CSL) model together with its dissipative (dCSL) and non-Markovian generalizations (cCSL), the quantum mechanics with universal position localization (QMUPL), and the Diósi-Penrose (DP) model. We discuss the separability of the dynamics of the collapse models along the three spatial directions, the validity of the paraxial approximation, and the amplification mechanism. We obtain analytical expressions both in the far field and near field limits. These results agree with those already derived in the Wigner function formalism. We compare the theoretical predictions with the experimental data from two recent matter-wave experiments: the 2012 far-field experiment of Juffmann T et al (2012 Nat. Nanotechnol. 7 297-300) and the 2013 Kapitza-Dirac-Talbot-Lau (KDTL) near-field experiment of Eibenberger et al (2013 Phys. Chem. Chem. Phys. 15 14696-700). We show the region of the parameter space for each collapse model that is excluded by these experiments. We show that matter-wave experiments provide model-insensitive bounds that are valid for a wide family of dissipative and non-Markovian generalizations.
Thermophysics Characterization of Kerosene Combustion
NASA Technical Reports Server (NTRS)
Wang, Ten-See
2000-01-01
A one-formula surrogate fuel formulation and its quasi-global combustion kinetics model are developed to support the design of injectors and thrust chambers of kerosene-fueled rocket engines. This surrogate fuel model depicts a fuel blend that properly represents the general physical and chemical properties of kerosene. The accompanying gaseous-phase thermodynamics of the surrogate fuel is anchored with the heat of formation of kerosene and verified by comparing a series of one-dimensional rocket thrust chamber calculations. The quasi-global combustion kinetics model consists of several global steps for parent fuel decomposition, soot formation, and soot oxidation, and a detailed wet-CO mechanism. The final thermophysics formulations are incorporated with a computational fluid dynamics model for prediction of the combustor efficiency of an uni-element, tri-propellant combustor and the radiation of a kerosene-fueled thruster plume. The model predictions agreed reasonably well with those of the tests.
Thermophysics Characterization of Kerosene Combustion
NASA Technical Reports Server (NTRS)
Wang, Ten-See
2001-01-01
A one-formula surrogate fuel formulation and its quasi-global combustion kinetics model are developed to support the design of injectors and thrust chambers of kerosene-fueled rocket engines. This surrogate fuel model depicts a fuel blend that properly represents the general physical and chemical properties of kerosene. The accompanying gaseous-phase thermodynamics of the surrogate fuel is anchored with the heat of formation of kerosene and verified by comparing a series of one-dimensional rocket thrust chamber calculations. The quasi-global combustion kinetics model consists of several global steps for parent fuel decomposition, soot formation, and soot oxidation and a detailed wet-CO mechanism to complete the combustion process. The final thermophysics formulations are incorporated with a computational fluid dynamics model for prediction of the combustion efficiency of an unielement, tripropellant combustor and the radiation of a kerosene-fueled thruster plume. The model predictions agreed reasonably well with those of the tests.
Validation of general job satisfaction in the Korean Labor and Income Panel Study.
Park, Shin Goo; Hwang, Sang Hee
2017-01-01
The purpose of this study is to assess the validity and reliability of general job satisfaction (JS) in the Korean Labor and Income Panel Study (KLIPS). We used the data from the 17th wave (2014) of the nationwide KLIPS, which selected a representative panel sample of Korean households and individuals aged 15 or older residing in urban areas. We included in this study 7679 employed subjects (4529 males and 3150 females). The general JS instrument consisted of five items rated on a scale from 1 (strongly disagree) to 5 (strongly agree). The general JS reliability was assessed using the corrected item-total correlation and Cronbach's alpha coefficient. The validity of general JS was assessed using confirmatory factor analysis (CFA) and Pearson's correlation. The corrected item-total correlations ranged from 0.736 to 0.837. Therefore, no items were removed. Cronbach's alpha for general JS was 0.925, indicating excellent internal consistency. The CFA of the general JS model showed a good fit. Pearson's correlation coefficients for convergent validity showed moderate or strong correlations. The results obtained in our study confirm the validity and reliability of general JS.
On the role of fluctuations in the modeling of complex systems.
NASA Astrophysics Data System (ADS)
Droz, Michel; Pekalski, Andrzej
2016-09-01
The study of models is ubiquitous in sciences like physics, chemistry, ecology, biology or sociology. Models are used to explain experimental facts or to make new predictions. For any system, one can distinguish several levels of description. In the simplest mean-field like description the dynamics is described in terms of spatially averaged quantities while in a microscopic approach local properties are taken into account and local fluctuations for the relevant variables are present. The properties predicted by these two different approaches may be drastically different. In a large body of research literature concerning complex systems this problem is often overlooked and simple mean-field like approximation are used without asking the question of the robustness of the corresponding predictions. The goal of this paper is twofold, first to illustrate the importance of the fluctuations in a self-contained and pedagogical way, by revisiting two different classes of problems where thorough investigations have been conducted (equilibrium and non-equilibrium statistical physics). Second, we present our original research on the dynamics of population of annual plants which are competing among themselves for just one resource (water) through a stochastic dynamics. Depending on the observable considered, the mean-field like and microscopic approaches agree or totally disagree. There is not a general criterion allowing to decide a priori when the two approaches will agree.
Dynamic properties of porous B sub 4 C. Interim report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brar, N.S.; Rosenberg, Z.; Bless, S.J.
1990-01-25
The sound speed in porous B4C (Boron Carbide) was measured and predicted on the basis of a spherical void model and a penny crack model. Neither model does well for porosity exceeding 10 percent. Measured values of Hugoniot elastic limit for porous B4C agree well with those predicted by the Steinberg's model. Measured transverse stress in the elastic range of B4C under 1-d strain condition agrees with the predictions.
NASA Astrophysics Data System (ADS)
Zhang, Hongliang; Li, Jingyi; Ying, Qi; Guven, Birnur Buzcu; Olaguer, Eduardo P.
2013-02-01
In this study, a source-oriented version of the Community Multiscale Air Quality (CMAQ) model was developed and used to quantify the contributions of five major local emission source types in Southeast Texas (vehicles, industry, natural gas combustion, wildfires, biogenic sources), as well as upwind sources, to regional primary and secondary formaldehyde (HCHO) concentrations. Predicted HCHO concentrations agree well with observations at two urban sites (the Moody Tower [MT] site at the University of Houston and the Haden Road #3 [HRM-3] site operated by Texas Commission on Environmental Quality). However, the model underestimates concentrations at an industrial site (Lynchburg Ferry). Throughout most of Southeast Texas, primary HCHO accounts for approximately 20-30% of total HCHO, while the remaining portion is due to secondary HCHO (30-50%) and upwind sources (20-50%). Biogenic sources, natural gas combustion, and vehicles are important sources of primary HCHO in the urban Houston area, respectively, accounting for 10-20%, 10-30%, and 20-60% of total primary HCHO. Biogenic sources, industry, and vehicles are the top three sources of secondary HCHO, respectively, accounting for 30-50%, 10-30%, and 5-15% of overall secondary HCHO. It was also found that over 70% of PAN in the Houston area is due to upwind sources, and only 30% is formed locally. The model-predicted source contributions to HCHO at the MT generally agree with source apportionment results obtained from the Positive Matrix Factorization (PMF) technique.
Solar Proton Transport within an ICRU Sphere Surrounded by a Complex Shield: Combinatorial Geometry
NASA Technical Reports Server (NTRS)
Wilson, John W.; Slaba, Tony C.; Badavi, Francis F.; Reddell, Brandon D.; Bahadori, Amir A.
2015-01-01
The 3DHZETRN code, with improved neutron and light ion (Z (is) less than 2) transport procedures, was recently developed and compared to Monte Carlo (MC) simulations using simplified spherical geometries. It was shown that 3DHZETRN agrees with the MC codes to the extent they agree with each other. In the present report, the 3DHZETRN code is extended to enable analysis in general combinatorial geometry. A more complex shielding structure with internal parts surrounding a tissue sphere is considered and compared against MC simulations. It is shown that even in the more complex geometry, 3DHZETRN agrees well with the MC codes and maintains a high degree of computational efficiency.
Code of Federal Regulations, 2012 CFR
2012-07-01
... FOR REGISTRATION OF ANTIMICROBIAL PESTICIDES Product Chemistry Data Requirements § 161.150 General. (a) Applicability. This subpart describes the product chemistry data that are required to support the registration... agreeing to abide by the standard limits in § 161.175). (4) Physical and chemical characteristics. (i) Data...
Code of Federal Regulations, 2010 CFR
2010-10-01
... patents, data, or know-how reflecting the primary source's investment in developing and engineering and... DEFENSE GENERAL CONTRACTING REQUIREMENTS PATENTS, DATA, AND COPYRIGHTS Foreign License and Technical..., referred to in this subpart as a “primary source,” agrees to furnish to a foreign concern or government...
NASA Astrophysics Data System (ADS)
Chan, M. H.
2013-05-01
I use the fact that the radiation emitted by the accretion disk of supermassive black hole can heat up the surrounding gas in the protogalaxy to achieve hydrostatic equilibrium during the galaxy formation. The correlation between the black hole mass M BH and velocity dispersion σ thus naturally arises. The result generally agrees with empirical fittings from observational data, even with M BH ≤106 M ⊙. This model provides a clear picture on how the properties of the galactic supermassive black holes are connected with the kinetic properties of the galactic bulges.
Nonlinear transport theory in the metal with tunnel barrier
NASA Astrophysics Data System (ADS)
Zubov, E. E.
2018-02-01
Within the framework of the scattering matrix formalism, the nonlinear Kubo theory for electron transport in the metal with a tunnel barrier has been considered. A general expression for the mean electrical current was obtained. It significantly simplifies the calculation of nonlinear contributions to the conductivity of various hybrid structures. In the model of the tunnel Hamiltonian, all linear and nonlinear contributions to a mean electrical current are evaluated. The linear approximation agrees with results of other theories. For effective barrier transmission ?, the ballistic transport is realised with a value of the Landauer conductivity equal to ?.
Granular fountains: convection cascade in a compartmentalized granular gas.
van der Meer, Devaraj; van der Weele, Ko; Reimann, Peter
2006-06-01
This paper extends the two-compartment granular fountain [D. van der Meer, P. Reimann, K. van der Weele, and D. Lohse, Phys. Rev. Lett. 92, 184301 (2004)] to an arbitrary number of compartments: the tendency of a granular gas to form clusters is exploited to generate spontaneous convective currents, with particles going down in the well-filled compartments and going up in the diluted ones. We focus upon the bifurcation diagram of the general -compartment system, which is constructed using a dynamical flux model and which proves to agree quantitatively with results from molecular dynamics simulations.
A general stochastic model for studying time evolution of transition networks
NASA Astrophysics Data System (ADS)
Zhan, Choujun; Tse, Chi K.; Small, Michael
2016-12-01
We consider a class of complex networks whose nodes assume one of several possible states at any time and may change their states from time to time. Such networks represent practical networks of rumor spreading, disease spreading, language evolution, and so on. Here, we derive a model describing the dynamics of this kind of network and a simulation algorithm for studying the network evolutionary behavior. This model, derived at a microscopic level, can reveal the transition dynamics of every node. A numerical simulation is taken as an ;experiment; or ;realization; of the model. We use this model to study the disease propagation dynamics in four different prototypical networks, namely, the regular nearest-neighbor (RN) network, the classical Erdös-Renyí (ER) random graph, the Watts-Strogátz small-world (SW) network, and the Barabási-Albert (BA) scalefree network. We find that the disease propagation dynamics in these four networks generally have different properties but they do share some common features. Furthermore, we utilize the transition network model to predict user growth in the Facebook network. Simulation shows that our model agrees with the historical data. The study can provide a useful tool for a more thorough understanding of the dynamics networks.
NASA Technical Reports Server (NTRS)
Gregg, Watson W.; Busalacchi, Antonio (Technical Monitor)
2000-01-01
A coupled ocean general circulation, biogeochemical, and radiative model was constructed to evaluate and understand the nature of seasonal variability of chlorophyll and nutrients in the global oceans. Biogeochemical processes in the model were determined from the influences of circulation and turbulence dynamics, irradiance availability, and the interactions among three functional phytoplankton groups (diatoms, chlorophytes, and picoplankton) and three nutrients (nitrate, ammonium, and silicate). Basin scale (>1000 km) model chlorophyll seasonal distributions were statistically positively correlated with CZCS chlorophyll in 10 of 12 major oceanographic regions, and with SeaWiFS in all 12. Notable disparities in magnitudes occurred, however, in the tropical Pacific, the spring/summer bloom in the Antarctic, autumn in the northern high latitudes, and during the southwest monsoon in the North Indian Ocean. Synoptic scale (100-1000 km) comparisons of satellite and in situ data exhibited broad agreement, although occasional departures were apparent. Model nitrate distributions agreed with in situ data, including seasonal dynamics, except for the equatorial Atlantic. The overall agreement of the model with satellite and in situ data sources indicated that the model dynamics offer a reasonably realistic simulation of phytoplankton and nutrient dynamics on basin and synoptic scales.
A Nonlocal Calculation of Circumstellar OH Masers
NASA Astrophysics Data System (ADS)
Collison, A. J.; Nedoluha, G. E.
1993-12-01
We present calculations for circumstellar OH masers which explicitly account for the nonlocal interaction throughout the masing region. Excitation temperatures and observed emission are calculated for all four ground state maser lines. All other transitions are treated using a modified Sobolev approximation. Calculations are performed within the context of a simplified dust/outflow model which provides the pumping conditions and their variation with radius. Total velocity relaxation is implicitly assumed in the calculations. We find general agreement with the qualitative results of earlier work (Collison & Nedoluha, ApJ, 10 Feb 94 issue) and agree with the conclusions of Alcock & Ross (1986, ApJ, 305, 837) who showed that observed profiles can not be produced by a smooth, spherically symmetric wind model of the outflow.
Optimum data weighting and error calibration for estimation of gravitational parameters
NASA Technical Reports Server (NTRS)
Lerch, Francis J.
1989-01-01
A new technique was developed for the weighting of data from satellite tracking systems in order to obtain an optimum least-squares solution and an error calibration for the solution parameters. Data sets from optical, electronic, and laser systems on 17 satellites in GEM-T1 Goddard Earth Model-T1 (GEM-T1) were employed toward application of this technique for gravity field parameters. Also GEM-T2 (31 satellites) was recently computed as a direct application of the method and is summarized. The method employs subset solutions of the data associated with the complete solution to agree with their error estimates. With the adjusted weights the process provides for an automatic calibration of the error estimates for the solution parameters. The data weights derived are generally much smaller than corresponding weights obtained from nominal values of observation accuracy or residuals. Independent tests show significant improvement for solutions with optimal weighting. The technique is general and may be applied to orbit parameters, station coordinates, or other parameters than the gravity model.
NASA Astrophysics Data System (ADS)
Lin-Liu, Y. R.; Chan, V. S.; Luce, T. C.; Prater, R.
1998-11-01
Owing to relativistic mass shift in the cyclotron resonance condition, a simple and accurate interpolation formula for estimating the current drive efficiency, such as those(S.C. Chiu et al.), Nucl. Fusion 29, 2175 (1989).^,(D.A. Ehst and C.F.F. Karney, Nucl. Fusion 31), 1933 (1991). commonly used in FWCD, is not available in the case of ECCD. In this work, we model ECCD using the adjoint techniques. A semi-analytic adjoint function appropriate for general tokamak geometry is obtained using Fisch's relativistic collision model. Predictions of off-axis ECCD qualitatively and semi-quantitatively agrees with those of Cohen,(R.H. Cohen, Phys. Fluids 30), 2442 (1987). currently implemented in the raytracing code TORAY. The dependences of the current drive efficiency on the wave launch configuration and the plasma parameters will be presented. Strong absorption of the wave away from the resonance layer is shown to be an important factor in optimizing the off-axis ECCD for application to advanced tokamak operations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hurricane, O. A.; Clark, D. S.
The work is summarized from several perspectives: 1D simulation perspective: Post-shot models agree with yield data to within a factor of ~2 at low implosion velocities, but the models diverge from the data as the velocity and convergence ratio increase. 2D simulation perspective: Integrated hohlraum-capsule post-shot models agree with primary data for most implosions, but overpredict yield and DSR for a few of the highest velocity implosions. High-resolution 3D post-shot capsule-only modeling captures much of the delivered performance of the one shot currently simulated.
NASA Astrophysics Data System (ADS)
Krishnan, M.
2017-05-01
We present a model for calculating the net and effective electrical charge of globular macromolecules and linear polyelectrolytes such as proteins and DNA, given the concentration of monovalent salt and pH in solution. The calculation is based on a numerical solution of the non-linear Poisson-Boltzmann equation using a finite element discretized continuum approach. The model simultaneously addresses the phenomena of charge regulation and renormalization, both of which underpin the electrostatics of biomolecules in solution. We show that while charge regulation addresses the true electrical charge of a molecule arising from the acid-base equilibria of its ionizable groups, charge renormalization finds relevance in the context of a molecule's interaction with another charged entity. Writing this electrostatic interaction free energy in terms of a local electrical potential, we obtain an "interaction charge" for the molecule which we demonstrate agrees closely with the "effective charge" discussed in charge renormalization and counterion-condensation theories. The predictions of this model agree well with direct high-precision measurements of effective electrical charge of polyelectrolytes such as nucleic acids and disordered proteins in solution, without tunable parameters. Including the effective interior dielectric constant for compactly folded molecules as a tunable parameter, the model captures measurements of effective charge as well as published trends of pKa shifts in globular proteins. Our results suggest a straightforward general framework to model electrostatics in biomolecules in solution. In offering a platform that directly links theory and experiment, these calculations could foster a systematic understanding of the interrelationship between molecular 3D structure and conformation, electrical charge and electrostatic interactions in solution. The model could find particular relevance in situations where molecular crystal structures are not available or rapid, reliable predictions are desired.
Improvement of Progressive Damage Model to Predicting Crashworthy Composite Corrugated Plate
NASA Astrophysics Data System (ADS)
Ren, Yiru; Jiang, Hongyong; Ji, Wenyuan; Zhang, Hanyu; Xiang, Jinwu; Yuan, Fuh-Gwo
2018-02-01
To predict the crashworthy composite corrugated plate, different single and stacked shell models are evaluated and compared, and a stacked shell progressive damage model combined with continuum damage mechanics is proposed and investigated. To simulate and predict the failure behavior, both of the intra- and inter- laminar failure behavior are considered. The tiebreak contact method, 1D spot weld element and cohesive element are adopted in stacked shell model, and a surface-based cohesive behavior is used to capture delamination in the proposed model. The impact load and failure behavior of purposed and conventional progressive damage models are demonstrated. Results show that the single shell could simulate the impact load curve without the delamination simulation ability. The general stacked shell model could simulate the interlaminar failure behavior. The improved stacked shell model with continuum damage mechanics and cohesive element not only agree well with the impact load, but also capture the fiber, matrix debonding, and interlaminar failure of composite structure.
Herrera-May, Agustín L.; Aguilera-Cortés, Luz A.; Plascencia-Mora, Hector; Rodríguez-Morales, Ángel L.; Lu, Jian
2011-01-01
Multilayered microresonators commonly use sensitive coating or piezoelectric layers for detection of mass and gas. Most of these microresonators have a variable cross-section that complicates the prediction of their fundamental resonant frequency (generally of the bending mode) through conventional analytical models. In this paper, we present an analytical model to estimate the first resonant frequency and deflection curve of single-clamped multilayered microresonators with variable cross-section. The analytical model is obtained using the Rayleigh and Macaulay methods, as well as the Euler-Bernoulli beam theory. Our model is applied to two multilayered microresonators with piezoelectric excitation reported in the literature. Both microresonators are composed by layers of seven different materials. The results of our analytical model agree very well with those obtained from finite element models (FEMs) and experimental data. Our analytical model can be used to determine the suitable dimensions of the microresonator’s layers in order to obtain a microresonator that operates at a resonant frequency necessary for a particular application. PMID:22164071
Intelligence Testing 1928-1978: What Next?
ERIC Educational Resources Information Center
Vernon, Philip E.
Attention is drawn to the ways in which current conceptions of intelligence and its measurement differ from those which were generally accepted in 1928. The following principles underlying intelligence testing were generally agreed upon in 1928: (1) the assumption of intelligence as a recognizable attribute, responsible for differences among…
Sperstad, Iver Bakken; Stålhane, Magnus; Dinwoodie, Iain; ...
2017-09-23
Optimising the operation and maintenance (O&M) and logistics strategy of offshore wind farms implies the decision problem of selecting the vessel fleet for O&M. Different strategic decision support tools can be applied to this problem, but much uncertainty remains regarding both input data and modelling assumptions. Our paper aims to investigate and ultimately reduce this uncertainty by comparing four simulation tools, one mathematical optimisation tool and one analytic spreadsheet-based tool applied to select the O&M access vessel fleet that minimizes the total O&M cost of a reference wind farm. The comparison shows that the tools generally agree on the optimalmore » vessel fleet, but only partially agree on the relative ranking of the different vessel fleets in terms of total O&M cost. The robustness of the vessel fleet selection to various input data assumptions was tested, and the ranking was found to be particularly sensitive to the vessels' limiting significant wave height for turbine access. Also the parameter with the greatest discrepancy between the tools, implies that accurate quantification and modelling of this parameter is crucial. The ranking is moderately sensitive to turbine failure rates and vessel day rates but less sensitive to electricity price and vessel transit speed.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sperstad, Iver Bakken; Stålhane, Magnus; Dinwoodie, Iain
Optimising the operation and maintenance (O&M) and logistics strategy of offshore wind farms implies the decision problem of selecting the vessel fleet for O&M. Different strategic decision support tools can be applied to this problem, but much uncertainty remains regarding both input data and modelling assumptions. Our paper aims to investigate and ultimately reduce this uncertainty by comparing four simulation tools, one mathematical optimisation tool and one analytic spreadsheet-based tool applied to select the O&M access vessel fleet that minimizes the total O&M cost of a reference wind farm. The comparison shows that the tools generally agree on the optimalmore » vessel fleet, but only partially agree on the relative ranking of the different vessel fleets in terms of total O&M cost. The robustness of the vessel fleet selection to various input data assumptions was tested, and the ranking was found to be particularly sensitive to the vessels' limiting significant wave height for turbine access. Also the parameter with the greatest discrepancy between the tools, implies that accurate quantification and modelling of this parameter is crucial. The ranking is moderately sensitive to turbine failure rates and vessel day rates but less sensitive to electricity price and vessel transit speed.« less
The Art and Science of Tactics
1977-01-01
THE ART AND SCIENCE OF TACTICS by MAJOR ROBERT A. DOUGHTY, US ARMY E stablishing the nature of tactics has been a pastime of professional...tactics in the US Army have implicitly begun to assume that tactics is more an exact science than an " art and science ." As one recent military writer...and 19th centuries generally agreed that tactics was more an art than it was a science . Many agreed with the terse definition given by Antoine
Applicability of Generalized Peek's Law to Scaling of Corona Onset Voltages in Electropositive Gases
NASA Astrophysics Data System (ADS)
Li, Yan-Ming
2008-10-01
We have developed the steady state positive corona model with the ionization zone physics in the point-plane configuration. The geometry is axisymmetric, consisting of a pointed anode of small tip radius and a planar cathode. The model solves the Poisson equation, drift dominated electron and the positive ion transport equations with the nonlinear Townsend ionization source terms, to give the complete electric field, electron and positive ion density distributions. The corona plasma properties can be determined as function of discharge current, ranging from the pico-ampere up to a milli-ampere. The calculated voltage-current characteristics obeyed the Townsend equation, agreeing with the general experimental observations. The model is applied to different electropositive gases, argon, xenon, nitrogen and mercury. Corona onset potentials are determined based on the discharge voltages at very low currents. Extensive parametric study for argon positive corona with varying anode tip radius, gap distance and gas pressure has been completed. All the simulated corona onset voltages are very well described by the generalized Peek's Law [1]. At sufficiently high current in the range of 0.1 mA, discharge filament is formed near the anode tip. [1] Peek F. W., Dielectric Phenomena in High Voltage Engineering, McGraw Hill, New York (1929).
New perspectives on an old problem: The bending of light in Yang-Mills gravity
NASA Astrophysics Data System (ADS)
Cottrell, Kazuo Ota; Hsu, Jong-Ping
Yang-Mills gravity with electromagnetism predicts, in the geometric optics limit, a value for the deflection of light by the sun which agrees closely with the reanalysis of Eddington's 1919 optical measurements done in 1979. Einstein's General Theory of Relativity, on the other hand, agrees very closely with measurements of the deflection of electromagnetic waves made in the range of radio frequencies. Since both General Relativity and Yang-Mills gravity with electromagnetism in the geometric optics limit make predictions for the optical region which fall within experimental uncertainty, it becomes important to consider the possibility of the existence of a frequency dependence in the measurement results for the deflection of light, in order to determine which theory more closely describes nature...
Attitudes toward Euthanasia in Hong Kong--A Comparison between Physicians and the General Public
ERIC Educational Resources Information Center
Chong, Alice Ming-lin; Fok, Shiu-yeu
2005-01-01
This article reports the findings of a cross-sectional study that compared the attitudes of 618 respondents of a general household survey and a random sample of 1,197 physicians toward different types of euthanasia in Hong Kong. The general public was found to agree with active euthanasia and non-voluntary euthanasia and was neutral about passive…
Developing Proactive Methods for General Aviation Data Collection
2010-11-01
standard weather package that all pilots would review before flying. 17. Key Words 18. Distribution Statement General Aviation...completed page authorized iii ACKNOWLEDGMENTS We are indebted to the many Flight Standards District Office employees that provided assistance beyond...Directive / Level of Effort Agree- ment between the Human Factors Research and Engineering Group (AJP-61), Flight Standards Service – General Aviation
The jet-disk symbiosis without maximal jets: 1D hydrodynamical jets revisited
NASA Astrophysics Data System (ADS)
Crumley, Patrick; Ceccobello, Chiara; Connors, Riley M. T.; Cavecchi, Yuri
2017-05-01
In this work we discuss the recent criticism by Zdziarski (2016, A&A, 586, A18) of the maximal jet model derived in Falcke & Biermann (1995, A&A, 293, 665). We agree with Zdziarski that in general a jet's internal energy is not bounded by its rest-mass energy density. We describe the effects of the mistake on conclusions that have been made using the maximal jet model and show when a maximal jet is an appropriate assumption. The maximal jet model was used to derive a 1D hydrodynamical model of jets in agnjet, a model that does multiwavelength fitting of quiescent/hard state X-ray binaries and low-luminosity active galactic nuclei. We correct algebraic mistakes made in the derivation of the 1D Euler equation and relax the maximal jet assumption. We show that the corrections cause minor differences as long as the jet has a small opening angle and a small terminal Lorentz factor. We find that the major conclusion from the maximal jet model, the jet-disk symbiosis, can be generally applied to astrophysical jets. We also show that isothermal jets are required to match the flat radio spectra seen in low-luminosity X-ray binaries and active galactic nuclei, in agreement with other works.
NASA Astrophysics Data System (ADS)
Meaud, Julien; Li, Yizeng; Grosh, Karl
2011-11-01
It is generally agreed that the nonlinear response of the cochlea is due to the forward transduction of the outer hair cell (OHC) hair bundle (HB) and subsequent alteration of the active force applied to the cochlear structures, including the basilar membrane (BM). A mechanical-acoustical-electrical model of the cochlea with three-dimensional fluid representation, and feedback from OHC somatic motility coupled to nonlinear HB mechanotransduction is used to predict nonlinear distortion of the BM response to acoustic stimulus. An efficient alternating frequency time scheme is implemented to solve for the nonlinear stationary dynamics of the cochlea. The model is used to predict the location of maximum generation of nonlinear distortion during pure tone and two-tone stimulation as well as the propagation of the distortion components on the BM.
NASA Astrophysics Data System (ADS)
Baird, M. E.; Walker, S. J.; Wallace, B. B.; Webster, I. T.; Parslow, J. S.
2003-03-01
A simple model of estuarine eutrophication is built on biomechanical (or mechanistic) descriptions of a number of the key ecological processes in estuaries. Mechanistically described processes include the nutrient uptake and light capture of planktonic and benthic autotrophs, and the encounter rates of planktonic predators and prey. Other more complex processes, such as sediment biogeochemistry, detrital processes and phosphate dynamics, are modelled using empirical descriptions from the Port Phillip Bay Environmental Study (PPBES) ecological model. A comparison is made between the mechanistically determined rates of ecological processes and the analogous empirically determined rates in the PPBES ecological model. The rates generally agree, with a few significant exceptions. Model simulations were run at a range of estuarine depths and nutrient loads, with outputs presented as the annually averaged biomass of autotrophs. The simulations followed a simple conceptual model of eutrophication, suggesting a simple biomechanical understanding of estuarine processes can provide a predictive tool for ecological processes in a wide range of estuarine ecosystems.
Can You Trust Self-Report Data Provided by Homeless Mentally Ill Individuals?
ERIC Educational Resources Information Center
Calsyn, Robert J.; And Others
1993-01-01
Reliability and validity of self-report data provided by 178 mentally ill homeless persons were generally favorable. Self-reports of service use also generally agreed with treatment staff estimates, providing further validity evidence. Researchers and administrators can be relatively confident in using such data. (SLD)
Code of Federal Regulations, 2010 CFR
2010-01-01
... powers necessary, to hear and decide, or to otherwise resolve through agreed procedures, appeals from... also imposes upon the Board the duty, and grants it powers necessary, to act upon petitions for orders... to give testimony, or both, 41 U.S.C. 610. (b) General Powers and Authorities. The Board's general...
Code of Federal Regulations, 2011 CFR
2011-01-01
... powers necessary, to hear and decide, or to otherwise resolve through agreed procedures, appeals from... also imposes upon the Board the duty, and grants it powers necessary, to act upon petitions for orders... to give testimony, or both, 41 U.S.C. 610. (b) General Powers and Authorities. The Board's general...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Porter, W.P.
1987-08-01
The vacuum gas-analysis system is running and we use doubly labeled water routinely in our research. We have the computer-controlled respirometer system running, and can routinely measure respiratory gases and body temperatures in small, living mammals. Our heat- and mass-balance model calculations of field metabolism and water loss agree exceptionally well with doubly labeled water measurements of the field metabolism and water loss for Sceloporus undulatus in the sandhill country of western Nebraska. We established theoretical links between our biophysical models of individual animals and population dynamics and community models in the literature. Our general, dry, porous-media model works formore » bird feathers as well as fur. Now heat and mass fluxes for any endotherm in any physical environment can be calculated with accuracy knowing only allometry, insulation properties, core or skin temperature and environmental conditions. We developed a general respiratory water-loss model using a coupled molar and heat balance. We developed a general counter-current heat exchange model with a peripheral heat generation and iterative skin temperature solution. We are testing our endotherm model on four species of temperate and tropical birds. We are completing parameter measurements for a test of the ectotherm model on an herbivorous lizard, like the test described above for the carnivorous lizard, Sceloporus undulatus. We have begun lab and field studies of the energetic costs of parasitism and climate on a small endotherm (using tapeworm infection of white-footed mice, Peromyscus leucopus). 8 figs.« less
Iwamoto, Yosuke; Ronningen, R M; Niita, Koji
2010-04-01
It has been sometimes necessary for personnel to work in areas where low-energy heavy ions interact with targets or with beam transport equipment and thereby produce significant levels of radiation. Methods to predict doses and to assist shielding design are desirable. The Particle and Heavy Ion Transport code System (PHITS) has been typically used to predict radiation levels around high-energy (above 100 MeV amu(-1)) heavy ion accelerator facilities. However, predictions by PHITS of radiation levels around low-energy (around 10 MeV amu(-1)) heavy ion facilities to our knowledge have not yet been investigated. The influence of the "switching time" in PHITS calculations of low-energy heavy ion reactions, defined as the time when the JAERI Quantum Molecular Dynamics model (JQMD) calculation stops and the Generalized Evaporation Model (GEM) calculation begins, was studied using neutron energy spectra from 6.25 MeV amu(-1) and 10 MeV amu(-1) (12)C ions and 10 MeV amu(-1) (16)O ions incident on a copper target. Using a value of 100 fm c(-1) for the switching time, calculated neutron energy spectra obtained agree well with the experimental data. PHITS was then used with the switching time of 100 fm c(-1) to simulate an experimental study by Ohnesorge et al. by calculating neutron dose equivalent rates produced by 3 MeV amu(-1) to 16 MeV amu(-1) (12)C, (14)N, (16)O, and (20)Ne beams incident on iron, nickel and copper targets. The calculated neutron dose equivalent rates agree very well with the data and follow a general pattern which appears to be insensitive to the heavy ion species but is sensitive to the target material.
Solar proton exposure of an ICRU sphere within a complex structure Part I: Combinatorial geometry.
Wilson, John W; Slaba, Tony C; Badavi, Francis F; Reddell, Brandon D; Bahadori, Amir A
2016-06-01
The 3DHZETRN code, with improved neutron and light ion (Z≤2) transport procedures, was recently developed and compared to Monte Carlo (MC) simulations using simplified spherical geometries. It was shown that 3DHZETRN agrees with the MC codes to the extent they agree with each other. In the present report, the 3DHZETRN code is extended to enable analysis in general combinatorial geometry. A more complex shielding structure with internal parts surrounding a tissue sphere is considered and compared against MC simulations. It is shown that even in the more complex geometry, 3DHZETRN agrees well with the MC codes and maintains a high degree of computational efficiency. Published by Elsevier Ltd.
NASA Technical Reports Server (NTRS)
Li, Xiao-Wen; Tao, Wei-Kuo; Khain, Alexander P.; Simpson, Joanne; Johnson, Daniel E.
2004-01-01
A cloud-resolving model is used to study sensitivities of two different microphysical schemes, one is the bulk type, and the other is an explicit bin scheme, in simulating a mid-latitude squall line case (PRE-STORM, June 10-11, 1985). Simulations using different microphysical schemes are compared with each other and also with the observations. Both the bulk and bin models reproduce the general features during the developing and mature stage of the system. The leading convective zone, the trailing stratiform region, the horizontal wind flow patterns, pressure perturbation associated with the storm dynamics, and the cool pool in front of the system all agree well with the observations. Both the observations and the bulk scheme simulation serve as validations for the newly incorporated bin scheme. However, it is also shown that, the bulk and bin simulations have distinct differences, most notably in the stratiform region. Weak convective cells exist in the stratiform region in the bulk simulation, but not in the bin simulation. These weak convective cells in the stratiform region are remnants of the previous stronger convections at the leading edge of the system. The bin simulation, on the other hand, has a horizontally homogeneous stratiform cloud structure, which agrees better with the observations. Preliminary examinations of the downdraft core strength, the potential temperature perturbation, and the evaporative cooling rate show that the differences between the bulk and bin models are due mainly to the stronger low-level evaporative cooling in convective zone simulated in the bulk model. Further quantitative analysis and sensitivity tests for this case using both the bulk and bin models will be presented in a companion paper.
Rep. Issa, Darrell E. [R-CA-49
2012-06-28
House - 06/28/2012 Motion to reconsider laid on the table Agreed to without objection. (All Actions) Notes: The committee report referred to in this resolution is H.Rept.112-546. Tracker: This bill has the status Agreed to in HouseHere are the steps for Status of Legislation:
2016-02-02
understanding is the experimental verification of a new model of light-induced loss spectra, employing continuum-dressed basis states, which agrees in...and additional qualifiers separated by commas, e.g. Smith, Richard, J, Jr. 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES). Self -explanatory... verification of a new model of light-induced loss spectra, employing continuum-dressed basis states, which agrees in shape and magnitude with all of our
A measurement-based generalized source model for Monte Carlo dose simulations of CT scans
Ming, Xin; Feng, Yuanming; Liu, Ransheng; Yang, Chengwen; Zhou, Li; Zhai, Hezheng; Deng, Jun
2018-01-01
The goal of this study is to develop a generalized source model (GSM) for accurate Monte Carlo dose simulations of CT scans based solely on the measurement data without a priori knowledge of scanner specifications. The proposed generalized source model consists of an extended circular source located at x-ray target level with its energy spectrum, source distribution and fluence distribution derived from a set of measurement data conveniently available in the clinic. Specifically, the central axis percent depth dose (PDD) curves measured in water and the cone output factors measured in air were used to derive the energy spectrum and the source distribution respectively with a Levenberg-Marquardt algorithm. The in-air film measurement of fan-beam dose profiles at fixed gantry was back-projected to generate the fluence distribution of the source model. A benchmarked Monte Carlo user code was used to simulate the dose distributions in water with the developed source model as beam input. The feasibility and accuracy of the proposed source model was tested on a GE LightSpeed and a Philips Brilliance Big Bore multi-detector CT (MDCT) scanners available in our clinic. In general, the Monte Carlo simulations of the PDDs in water and dose profiles along lateral and longitudinal directions agreed with the measurements within 4%/1mm for both CT scanners. The absolute dose comparison using two CTDI phantoms (16 cm and 32 cm in diameters) indicated a better than 5% agreement between the Monte Carlo-simulated and the ion chamber-measured doses at a variety of locations for the two scanners. Overall, this study demonstrated that a generalized source model can be constructed based only on a set of measurement data and used for accurate Monte Carlo dose simulations of patients’ CT scans, which would facilitate patient-specific CT organ dose estimation and cancer risk management in the diagnostic and therapeutic radiology. PMID:28079526
Global Mean Temperature Timeseries Projections from GCMs: The Implications of Rebasing
NASA Astrophysics Data System (ADS)
Chapman, S. C.; Stainforth, D. A.; Watkins, N. W.
2017-12-01
Global climate models are assessed by comparison with observations through several benchmarks. One highlighted by the InterGovernmental Panel on Climate Change (IPCC) is their ability to reproduce "general features of the global and annual mean surface temperature changes over the historical period" [1,2] and to simulate "a trend in global-mean surface temperature from 1951 to 2012 that agrees with the observed trend" [3]. These aspects of annual mean global mean temperature (GMT) change are presented as one feature demonstrating the relevance of these models for climate projections. Here we consider a formal interpretation of "general features" and discuss the implications of this approach to model assessment and intercomparison, for the interpretation of GCM projections. Following the IPCC, we interpret a major element of "general features" as being the slow timescale response to external forcings. (Shorter timescale behaviour such as the response to volcanic eruptions are also elements of "general features" but are not considered here.) Also following the IPCC, we consider only GMT anomalies. The models have absolute temperatures which range over about 3K so this means their timeseries (and the observations) are rebased. We show that rebasing in combination with general agreement, implies a separation of scales which limits the degree to which sub-global behaviour can feedback on the global response. It also implies a degree of linearity in the GMT slow timescale response. For each individual model these implications only apply over the range of absolute temperatures simulated by the model in historic simulations. Taken together, however, they imply consequences over a wider range of GMTs. [1] IPCC, Fifth Assessment Report, Working Group 1, Technical Summary: Stocker et al. 2013. [2] IPCC, Fifth Assessment Report, Working Group 1, Chapter 9 - "Evaluation of Climate Models": Flato et al. 2013. [3] IPCC, Fifth Assessment Report, Working Group 1, Summary for Policy Makers: IPCC, 2013.
A measurement-based generalized source model for Monte Carlo dose simulations of CT scans
NASA Astrophysics Data System (ADS)
Ming, Xin; Feng, Yuanming; Liu, Ransheng; Yang, Chengwen; Zhou, Li; Zhai, Hezheng; Deng, Jun
2017-03-01
The goal of this study is to develop a generalized source model for accurate Monte Carlo dose simulations of CT scans based solely on the measurement data without a priori knowledge of scanner specifications. The proposed generalized source model consists of an extended circular source located at x-ray target level with its energy spectrum, source distribution and fluence distribution derived from a set of measurement data conveniently available in the clinic. Specifically, the central axis percent depth dose (PDD) curves measured in water and the cone output factors measured in air were used to derive the energy spectrum and the source distribution respectively with a Levenberg-Marquardt algorithm. The in-air film measurement of fan-beam dose profiles at fixed gantry was back-projected to generate the fluence distribution of the source model. A benchmarked Monte Carlo user code was used to simulate the dose distributions in water with the developed source model as beam input. The feasibility and accuracy of the proposed source model was tested on a GE LightSpeed and a Philips Brilliance Big Bore multi-detector CT (MDCT) scanners available in our clinic. In general, the Monte Carlo simulations of the PDDs in water and dose profiles along lateral and longitudinal directions agreed with the measurements within 4%/1 mm for both CT scanners. The absolute dose comparison using two CTDI phantoms (16 cm and 32 cm in diameters) indicated a better than 5% agreement between the Monte Carlo-simulated and the ion chamber-measured doses at a variety of locations for the two scanners. Overall, this study demonstrated that a generalized source model can be constructed based only on a set of measurement data and used for accurate Monte Carlo dose simulations of patients’ CT scans, which would facilitate patient-specific CT organ dose estimation and cancer risk management in the diagnostic and therapeutic radiology.
Hassali, Mohamed Azmi Ahmad; Al-Haddad, Mahmoud; Shafie, Asrul Akmal; Tangiisuran, Balamurugan; Saleem, Fahad; Atif, Muhammad; Al-Qazaz, Harith
2012-06-01
This study aims to explore the perceptions of general practitioners (GPs) from the state of Penang toward the feasibility of implementing the medication reconciliation program in Malaysia. A cross-sectional descriptive study using a validated, self-completed anonymous 18-item questionnaire was undertaken over a period of 2 months in 2010. The study was conducted in the state of Penang, Malaysia. A letter consisting of survey questionnaires and prepaid return envelope were mailed to 429 GPs identified from the Private Medical Practice Control Department Registry. A total of 86 responses were received with response rate of 20.1%. Majority (90.1%) of the respondents agreed that medication reconciliation can be a feasible strategy to improve medication safety, and 97.7% confirmed that having an accurate up-to-date list of the patient's previous medication will be useful in the rational prescribing process. However, about half (56.9%) of them felt that standardization of the medication reconciliation process in all clinics will be difficult to achieve. Three quarters (73.2%) of the respondents believed that the involvement of GPs alone is insufficient, and 74.5% agreed that this program should be expanded to community pharmacy setting. More than 90% of the respondents agreed upon the medication reconciliation card proposed by the researchers. General practitioners in Penang are generally in favor of the implementation of medication reconciliation program in their practice. Because medication reconciliation has been shown to reduce many medicine-related problems, it is thus worth considering the feasibility of nationwide implementation of such program.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 105-68.645 Public Contracts and Property Management Federal Property Management Regulations System...-GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) General Principles Relating to Suspension and Debarment... voluntary exclusion? (a) Yes, we enter information regarding a voluntary exclusion into the EPLS. (b) Also...
Endoreversible quantum heat engines in the linear response regime.
Wang, Honghui; He, Jizhou; Wang, Jianhui
2017-07-01
We analyze general models of quantum heat engines operating a cycle of two adiabatic and two isothermal processes. We use the quantum master equation for a system to describe heat transfer current during a thermodynamic process in contact with a heat reservoir, with no use of phenomenological thermal conduction. We apply the endoreversibility description to such engine models working in the linear response regime and derive expressions of the efficiency and the power. By analyzing the entropy production rate along a single cycle, we identify the thermodynamic flux and force that a linear relation connects. From maximizing the power output, we find that such heat engines satisfy the tight-coupling condition and the efficiency at maximum power agrees with the Curzon-Ahlborn efficiency known as the upper bound in the linear response regime.
The dual loop model: its relation to language and other modalities
Rijntjes, Michel; Weiller, Cornelius; Bormann, Tobias; Musso, Mariacristina
2012-01-01
The current neurobiological consensus of a general dual loop system scaffolding human and primate brains gives evidence that the dorsal and ventral connections subserve similar functions, independent of the modality and species. However, most current commentators agree that although bees dance and chimpanzees grunt, these systems of communication differ qualitatively from human language. So why is language unique to humans? We discuss anatomical differences between humans and other animals, the meaning of lesion studies in patients, the role of inner speech, and compare functional imaging studies in language with other modalities in respect to the dual loop model. These aspects might be helpful for understanding what kind of biological system the language faculty is, and how it relates to other systems in our own species and others. PMID:22783188
Anisotropic neutron stars in R2 gravity
NASA Astrophysics Data System (ADS)
Folomeev, Vladimir
2018-06-01
We consider static neutron stars within the framework of R2 gravity. The neutron fluid is described by three different types of realistic equations of state (soft, moderately stiff, and stiff). Using the observational data on the neutron star mass-radius relation, it is demonstrated that the characteristics of the objects supported by the isotropic fluid agree with the observations only if one uses the soft equation of state. We show that the inclusion of the fluid anisotropy enables one also to employ more stiff equations of state to model configurations that will satisfy the observational constraints sufficiently. Also, using the standard thin accretion disk model, we demonstrate potentially observable differences, which allow us to distinguish the neutron stars constructed within the modified gravity framework from those described in Einstein's general relativity.
Fatigue of graphite/epoxy /0/90/45/-45/s laminates under dual stress levels
NASA Technical Reports Server (NTRS)
Yang, J. N.; Jones, D. L.
1982-01-01
A model for the prediction of loading sequence effects on the statistical distribution of fatigue life and residual strength in composite materials is generalized and applied to (0/90/45/-45)s graphite/epoxy laminates. Load sequence effects are found to be caused by both the difference in residual strength when failure occurs (boundary effect) and the effect of previously applied loads (memory effect). The model allows the isolation of these two effects, and the estimation of memory effect magnitudes under dual fatigue loading levels. It is shown that the material memory effect is insignificant, and that correlations between predictions of the number of early failures agree with the verification tests, as do predictions of fatigue life and residual strength degradation under dual stress levels.
European standardization effort: interworking the goal
NASA Astrophysics Data System (ADS)
Mattheus, Rudy A.
1993-09-01
In the European Standardization Committee (CEN), the technical committee responsible for the standardization activities in Medical Informatics (CEN TC 251), has agreed upon the directions of the scopes to follow in this field. They are described in the Directory of the European Standardization Requirements for Healthcare Informatics and Programme for the Development of Standards adopted on 02-28-1991 by CEN/TC 251 and approved by CEN/BT. Top-down objectives describe the common framework and items like terminology, security, more bottom up oriented items describe fields like medical imaging and multi-media. The draft standard is described; the general framework model and object oriented model; the interworking aspects, the relation to ISO standards, and the DICOM proposal. This paper also focuses on all the boundaries in the standardization work, which are also influencing the standardization process.
[Self-esteem Level in Scholarized Adolescents of the Rural Area of Pereira, Colombia].
González, Iris Tatiana Montes; Ramírez, Viviana Escudero; Martínez, José William
2012-09-01
To assess the level of self-esteem of adolescents in a rural school of a district of Pereira. Students were called upon to participate, 292 agreed to undergo the test, while 20 abstained. After a previous reliability test analysis, we found that 47.9% of students had low and very low self esteem. A multivariate model reported that self-esteem was reduced as age increased. The academic community and the family must work together in order to improve self-esteem among teenagers in general. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
NASA Technical Reports Server (NTRS)
Abel, I.; Perry, B., III; Newsom, J. R.
1982-01-01
Two flutter suppression control laws wre designed and tested on a low speed aeroelastic model of a DC-10 derivative wing. Both control laws demontrated increases in flutter speed in excess of 25 percent above the passive wing flutter speed. In addition, one of the control laws was effective in reducing loads due to turbulence generated in the wind tunnel. The effect of variations in gain and phase on the closed-loop performance was measured and is compared with predictions. In general, both flutter and gust response predictions agree reasonably well with experimental data.
Assay of the Martian Regolith with Neutrons
NASA Technical Reports Server (NTRS)
Drake, Darrell M.; Reedy, R.; Jakowsky, B.; Clark, B.; Squyres, S.
1998-01-01
Different aspects of assaying Martian regolith using neutrons have been investigated. The epithermal portion of moderated neutrons spectra is dramatically effected by the presence of hydrogen (usually in the form of water). A simple analytic formula has been derived to describe the amplitude of this portion of the neutron spectrum as a function of water concentration. Several demonstration experiments have been performed and modeled with a Monte Carlo code. Results of these experiments generally agreed with the calculations to within 20%. In addition to He-3 detectors, lithium-glass scintillators and U-238 fission ion chambers were investigated to determine their applicability to space experiments.
The Size Distribution of Jupiter-Family Cometary Nuclei
NASA Technical Reports Server (NTRS)
Weissman, Paul R.; Lowry, Stephen C.
2003-01-01
Introduction: We are continuing our program to determine the size distribution of cometary nuclei. We have compiled a catalog of 105 measurements of 57 cometary nuclei, drawn from the general literature, from our own program of CCD photometry of distant cometary nuclei (Lowry and Weissman), and from unpublished observations by colleagues. We model the cumulative size distribution of the nuclei as a power law. Previous determinations of the size distribution slope do not agree. Fernandez et al. found a slope of alpha = 2.65+/-0.25 whereas Lowry et al. and Weissman and Lowry each found a slope of alpha = 1.60+/-0.10.
An analytical and experimental evaluation of shadow shields and their support members
NASA Technical Reports Server (NTRS)
Stochl, R. J.; Boyle, R. J.
1972-01-01
Experimental tests were performed on a model shadow shield thermal protection system to examine the effect of certain configuration variables. The experimental results were used to verify the ability of an analytical program to predict the shadow shield performance including the shield-support interaction. In general, the analysis (assuming diffuse surfaces) agreed well with the experimental support temperature profiles. The agreement for the shield profiles was not as good. The results demonstrated: (1) shadow shields can be effective in reducing the heat transfer into cryogenic propellant tanks, and (2) the conductive heat transfer through supports can be reduced by selective surface coatings.
Review and developments of dissemination models for airborne carbon fibers
NASA Technical Reports Server (NTRS)
Elber, W.
1980-01-01
Dissemination prediction models were reviewed to determine their applicability to a risk assessment for airborne carbon fibers. The review showed that the Gaussian prediction models using partial reflection at the ground agreed very closely with a more elaborate diffusion analysis developed for the study. For distances beyond 10,000 m the Gaussian models predicted a slower fall-off in exposure levels than the diffusion models. This resulting level of conservatism was preferred for the carbon fiber risk assessment. The results also showed that the perfect vertical-mixing models developed herein agreed very closely with the diffusion analysis for all except the most stable atmospheric conditions.
Miyata, Hiroaki; Tachimori, Hisateru; Takahashi, Miyako; Saito, Tami; Kai, Ichiro
2004-01-01
Background This study aimed to ask a sample of the general population about their preferences regarding doctors holding discretionary powers in relation to disclosing cancer diagnosis and prognosis. Methods The researchers mailed 443 questionnaires to registered voters in a ward of Tokyo which had a socio-demographic profile similar to greater Tokyo's average and received 246 responses (response rate 55.5%). We describe and analysed respondents' attitudes toward doctors and family members holding discretionary powers in relation to cancer diagnoses disclose. Results Amongst respondents who wanted full disclosure about the diagnosis without delay, 117 (69.6 %) respondents agreed to follow the doctor's discretion, whilst 111 (66.1 %) respondents agreed to follow the family member's decision. For respondents who preferred to have the diagnosis and prognosis withheld, 59 (26.5 %) agreed to follow the doctor's decision, and 79 (35.3 %) of respondents agreed with following family member's wishes. Conclusions The greater proportion of respondents wants or permits disclosure of cancer diagnosis and prognosis. In patients who reveal negative attitudes toward being given a cancer disclosure directly, alternative options exist such as telling the family ahead of the patient or having a discussion of the cancer diagnosis with the patient together with the family. It is recommended that health professionals become more aware about the need to provide patients with their cancer diagnosis and prognosis in a variety of ways. PMID:15571636
Kolt, Gregory S; Oliver, Melody; Schofield, Grant M; Kerse, Ngaire; Garrett, Nick; Latham, Nancy K
2006-09-01
Despite the benefits associated with a physically active lifestyle, many older adults are insufficiently active to achieve health gain, and also exhibit decreased activity levels with age. Insufficient physical activity in this population is associated with increased morbidity, mortality and demand on health care services and expenditure. There is a clear need for effective intervention to encourage physical activity in older adults. The aim of this paper is to describe the development and participant evaluation of a randomized controlled trial of TeleWalk, a telephone-based motivational counseling intervention to encourage physical activity in adults aged 65 years and older. Participants (N = 186, mean age 74 +/- 6 years) were recruited through their General Practitioner (primary care physician) and randomized to either receive eight telephone counseling sessions and related printed materials over 3 months (intervention group) or participate in outcome assessments only (control group). Intervention group participants were mailed an anonymous evaluation questionnaire on intervention completion. A high response rate was achieved (70%). All respondents (100%) agreed or strongly agreed that a good overall level of service and support was provided, and that the counselor was understanding and supportive. Nearly all respondents agreed or strongly agreed that the service was professional, the counselor advice was helpful and motivating and the information provided was relevant (97, 95 and 89%, respectively). Most (87%) agreed or strongly agreed that the telephone calls encouraged them to be physically active. Among the participants who received printed material, most agreed or strongly agreed that these encouraged them to become or remain active. Findings from this evaluation can be used to inform such interventions and ensure their relevance to community-dwelling older adults.
Student evaluation of clickers in a combined dental and dental hygiene periodontology course.
Satheesh, Keerthana M; Saylor-Boles, Catherine D; Rapley, John W; Liu, Ying; Gadbury-Amyot, Cynthia C
2013-10-01
The purpose of this report is to describe the general use of clickers as an active learning tool and how they were used in teaching a combined periodontology course for second-year dental and junior dental hygiene students. A survey was used to capture student perceptions following completion of the course. Specific domains were active learning, improved performance, and expectations. The survey response rate was 94.5 percent (121/128). Descriptive analyses showed that, in the domain of active learning, 102 (84.3 percent) agreed/strongly agreed that the use of clickers made the lectures more interactive; sixty-six (54.5 percent) agreed/strongly agreed that the clickers made them focus; and ninety-two (76 percent) agreed/strongly agreed that the clickers encouraged active participation. In the domain regarding improved performance, sixty-three (52 percent) agreed/ strongly agreed that the review sessions utilizing clickers helped them prepare for tests. In the domain of expectations, ninety-three (76.9 percent) had a better idea of what to expect on the examination due to the use of clickers, and seventy-three (60.3 percent) thought that the clickers should be used in future semesters for this class. In addition, faculty members appreciated the greater participation afforded through the use of clickers to obtain a better understanding of the students' grasp of course content. Learning theory suggests that students must actively engage in the learning process in order for meaningful learning in the form of critical thinking and problem-solving to take place. In this study, students confirmed that the use of clicker technology encouraged their active participation in a periodontology course.
Levant, Ronald F; Hall, Rosalie J; Rankin, Thomas J
2013-04-01
The current study reports the development from the Male Role Norms Inventory-Revised (MRNI-R; Levant, Rankin, Williams, Hasan, & Smalley, 2010) of the 21-item MRNI-Short Form (MRNI-SF). Confirmatory factor analysis of MRNI-SF responses from a sample of 1,017 undergraduate participants (549 men, 468 women) indicated that the best fitting "bifactor" model incorporated the hypothesized 7-factor structure while explicitly modeling an additional, general traditional masculinity ideology factor. Specifically, each item-level indicator loaded on 2 factors: a general traditional masculinity ideology factor and a specific factor corresponding to 1 of the 7 hypothesized traditional masculinity ideology norms. The bifactor model was assessed for measurement invariance across gender groups, with findings of full configural invariance and partial metric invariance, such that factor loadings were equivalent across the gender groups for the 7 specific factors but not for the general traditional masculinity ideology factor. Theoretical explanations for this latter result include the potential that men's sense of self or identity may be engaged when responding to questions asking to what extent they agree or disagree with normative statements about their behavior, a possibility that could be investigated in future research by examining the associations of the general and specific factors with measures of masculine identity. Additional exploratory invariance analyses demonstrated latent mean differences between men and women on 4 of the 8 factors, and equivocal results for invariance of item intercepts, item uniquenesses, and factor variances-covariances.
NASA Astrophysics Data System (ADS)
López-Puertas, Manuel; Funke, B.; Jurado-Navarro, Á. A.; García-Comas, M.; Gardini, A.; Boone, C. D.; Rezac, L.; Garcia, R. R.
2017-08-01
We present the validation of Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) CO2 daytime concentration in the mesosphere and lower thermosphere by comparing with Atmospheric Chemistry Experiment (ACE) Fourier transform spectrometer and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) data. MIPAS shows a very good agreement with ACE below 100 km with differences of ˜5%. Above 100 km, MIPAS CO2 is generally lower than ACE with differences growing from ˜5% at 100 km to 20-40% near 110-120 km. Part of this disagreement can be explained by the lack of a nonlocal thermodynamic equilibrium correction in ACE. MIPAS also agrees very well (˜5%) with SABER below 100 km. At 90-105 km, MIPAS is generally smaller than SABER by 10-30% in the polar summers. At 100-120 km, MIPAS and SABER CO2 agree within ˜10% during equinox but, for solstice, MIPAS is larger by 10-25%, except near the polar summer. Whole Atmosphere Community Climate Model (WACCM) CO2 shows the major MIPAS features. At 75-100 km, the agreement is very good (˜5%), with maximum differences of ˜10%. At 95-115 km MIPAS CO2 is larger than WACCM by 20-30% in the winter hemisphere but smaller (20-40%) in the summer. Above 95-100 km WACCM generally overestimates MIPAS CO2 by about 20-80% except in the polar summer where underestimates it by 20-40%. MIPAS CO2 favors a large eddy diffusion below 100 km and suggests that the meridional circulation of the lower thermosphere is stronger than in WACCM. The three instruments and WACCM show a clear increase of CO2 with time, more markedly at 90-100 km.
Systematic evaluation of clinical practice guidelines for pharmacogenomics.
Beckett, Robert D; Kisor, David F; Smith, Thomas; Vonada, Brooke
2018-06-01
To systematically assess methodological quality of pharmacogenomics clinical practice guidelines. Guidelines published through 2017 were reviewed by at least three independent reviewers using the AGREE II instrument, which consists of 23 items grouped into 6 domains and 2 items representing an overall assessment. Items were assessed on a seven-point rating scale, and aggregate quality scores were calculated. 31 articles were included. All guidelines were published as peer-reviewed articles and 90% (n = 28) were endorsed by professional organizations. Mean AGREE II domain scores (maximum score 100%) ranged from 46.6 ± 11.5% ('applicability') to 78.9 ± 11.4% ('clarity of presentation'). Median overall quality score was 72.2% (IQR: 61.1-77.8%). Quality of pharmacogenomics guidelines was generally high, but variable, for most AGREE II domains.
Presenting an evaluation model of the trauma registry software.
Asadi, Farkhondeh; Paydar, Somayeh
2018-04-01
Trauma is a major cause of 10% death in the worldwide and is considered as a global concern. This problem has made healthcare policy makers and managers to adopt a basic strategy in this context. Trauma registry has an important and basic role in decreasing the mortality and the disabilities due to injuries resulted from trauma. Today, different software are designed for trauma registry. Evaluation of this software improves management, increases efficiency and effectiveness of these systems. Therefore, the aim of this study is to present an evaluation model for trauma registry software. The present study is an applied research. In this study, general and specific criteria of trauma registry software were identified by reviewing literature including books, articles, scientific documents, valid websites and related software in this domain. According to general and specific criteria and related software, a model for evaluating trauma registry software was proposed. Based on the proposed model, a checklist designed and its validity and reliability evaluated. Mentioned model by using of the Delphi technique presented to 12 experts and specialists. To analyze the results, an agreed coefficient of %75 was determined in order to apply changes. Finally, when the model was approved by the experts and professionals, the final version of the evaluation model for the trauma registry software was presented. For evaluating of criteria of trauma registry software, two groups were presented: 1- General criteria, 2- Specific criteria. General criteria of trauma registry software were classified into four main categories including: 1- usability, 2- security, 3- maintainability, and 4-interoperability. Specific criteria were divided into four main categories including: 1- data submission and entry, 2- reporting, 3- quality control, 4- decision and research support. The presented model in this research has introduced important general and specific criteria of trauma registry software and sub criteria related to each main criteria separately. This model was validated by experts in this field. Therefore, this model can be used as a comprehensive model and a standard evaluation tool for measuring efficiency and effectiveness and performance improvement of trauma registry software. Copyright © 2018 Elsevier B.V. All rights reserved.
Describing a Strongly Correlated Model System with Density Functional Theory.
Kong, Jing; Proynov, Emil; Yu, Jianguo; Pachter, Ruth
2017-07-06
The linear chain of hydrogen atoms, a basic prototype for the transition from a metal to Mott insulator, is studied with a recent density functional theory model functional for nondynamic and strong correlation. The computed cohesive energy curve for the transition agrees well with accurate literature results. The variation of the electronic structure in this transition is characterized with a density functional descriptor that yields the atomic population of effectively localized electrons. These new methods are also applied to the study of the Peierls dimerization of the stretched even-spaced Mott insulator to a chain of H 2 molecules, a different insulator. The transitions among the two insulating states and the metallic state of the hydrogen chain system are depicted in a semiquantitative phase diagram. Overall, we demonstrate the capability of studying strongly correlated materials with a mean-field model at the fundamental level, in contrast to the general pessimistic view on such a feasibility.
Analysis of Mathematical Modelling on Potentiometric Biosensors
Mehala, N.; Rajendran, L.
2014-01-01
A mathematical model of potentiometric enzyme electrodes for a nonsteady condition has been developed. The model is based on the system of two coupled nonlinear time-dependent reaction diffusion equations for Michaelis-Menten formalism that describes the concentrations of substrate and product within the enzymatic layer. Analytical expressions for the concentration of substrate and product and the corresponding flux response have been derived for all values of parameters using the new homotopy perturbation method. Furthermore, the complex inversion formula is employed in this work to solve the boundary value problem. The analytical solutions obtained allow a full description of the response curves for only two kinetic parameters (unsaturation/saturation parameter and reaction/diffusion parameter). Theoretical descriptions are given for the two limiting cases (zero and first order kinetics) and relatively simple approaches for general cases are presented. All the analytical results are compared with simulation results using Scilab/Matlab program. The numerical results agree with the appropriate theories. PMID:25969765
Analysis of mathematical modelling on potentiometric biosensors.
Mehala, N; Rajendran, L
2014-01-01
A mathematical model of potentiometric enzyme electrodes for a nonsteady condition has been developed. The model is based on the system of two coupled nonlinear time-dependent reaction diffusion equations for Michaelis-Menten formalism that describes the concentrations of substrate and product within the enzymatic layer. Analytical expressions for the concentration of substrate and product and the corresponding flux response have been derived for all values of parameters using the new homotopy perturbation method. Furthermore, the complex inversion formula is employed in this work to solve the boundary value problem. The analytical solutions obtained allow a full description of the response curves for only two kinetic parameters (unsaturation/saturation parameter and reaction/diffusion parameter). Theoretical descriptions are given for the two limiting cases (zero and first order kinetics) and relatively simple approaches for general cases are presented. All the analytical results are compared with simulation results using Scilab/Matlab program. The numerical results agree with the appropriate theories.
Numerical simulation for the air entrainment of aerated flow with an improved multiphase SPH model
NASA Astrophysics Data System (ADS)
Wan, Hang; Li, Ran; Pu, Xunchi; Zhang, Hongwei; Feng, Jingjie
2017-11-01
Aerated flow is a complex hydraulic phenomenon that exists widely in the field of environmental hydraulics. It is generally characterised by large deformation and violent fragmentation of the free surface. Compared to Euler methods (volume of fluid (VOF) method or rigid-lid hypothesis method), the existing single-phase Smooth Particle Hydrodynamics (SPH) method has performed well for solving particle motion. A lack of research on interphase interaction and air concentration, however, has affected the application of SPH model. In our study, an improved multiphase SPH model is presented to simulate aeration flows. A drag force was included in the momentum equation to ensure accuracy of the air particle slip velocity. Furthermore, a calculation method for air concentration is developed to analyse the air entrainment characteristics. Two studies were used to simulate the hydraulic and air entrainment characteristics. And, compared with the experimental results, the simulation results agree with the experimental results well.
Modeling Business Processes in Public Administration
NASA Astrophysics Data System (ADS)
Repa, Vaclav
During more than 10 years of its existence business process modeling became a regular part of organization management practice. It is mostly regarded. as a part of information system development or even as a way to implement some supporting technology (for instance workflow system). Although I do not agree with such reduction of the real meaning of a business process, it is necessary to admit that information technologies play an essential role in business processes (see [1] for more information), Consequently, an information system is inseparable from a business process itself because it is a cornerstone of the general basic infrastructure of a business. This fact impacts on all dimensions of business process management. One of these dimensions is the methodology that postulates that the information systems development provide the business process management with exact methods and tools for modeling business processes. Also the methodology underlying the approach presented in this paper has its roots in the information systems development methodology.
Lee, Hwang; Byun, Da-Eun; Kim, Ju Min; Kwon, Jung-Hwan
2018-01-01
To evaluate rate of migration from plastic debris, desorption of model hydrophobic organic chemicals (HOCs) from polyethylene (PE)/polypropylene (PP) films to water was measured using PE/PP films homogeneously loaded with the HOCs. The HOCs fractions remaining in the PE/PP films were compared with those predicted using a model characterized by the mass transfer Biot number. The experimental data agreed with the model simulation, indicating that HOCs desorption from plastic particles can generally be described by the model. For hexachlorocyclohexanes with lower plastic-water partition coefficients, desorption was dominated by diffusion in the plastic film, whereas desorption of chlorinated benzenes with higher partition coefficients was determined by diffusion in the aqueous boundary layer. Evaluation of the fraction of HOCs remaining in plastic films with respect to film thickness and desorption time showed that the partition coefficient between plastic and water is the most important parameter influencing the desorption half-life. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zeng, Hao; Xie, Zhimin; Gu, Jianping; Sun, Huiyu
2018-03-01
A new thermomechanical network transition constitutive model is proposed in the study to describe the viscoelastic behavior of shape memory polymers (SMPs). Based on the microstructure of semi-crystalline SMPs, a new simplified transformation equation is proposed to describe the transform of transient networks. And the generalized fractional Maxwell model is introduced in the paper to estimate the temperature-dependent storage modulus. In addition, a neo-KAHR theory with multiple discrete relaxation processes is put forward to study the structural relaxation of the nonlinear thermal strain in cooling/heating processes. The evolution equations of the time- and temperature-dependent stress and strain response are developed. In the model, the thermodynamical and mechanical characteristics of SMPs in the typical thermomechanical cycle are described clearly and the irreversible deformation is studied in detail. Finally, the typical thermomechanical cycles are simulated using the present constitutive model, and the simulation results agree well with the experimental results.
NASA Technical Reports Server (NTRS)
Yu, Hongbin; Chin, Mian; Winker, David M.; Omar, Ali H.; Liu, Zhaoyan; Kittaka, Chieko; Diehl, Thomas
2010-01-01
This study examines seasonal variations of the vertical distribution of aerosols through a statistical analysis of the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) lidar observations from June 2006 to November 2007. A data-screening scheme is developed to attain good quality data in cloud-free conditions, and the polarization measurement is used to separate dust from non-dust aerosol. The CALIPSO aerosol observations are compared with aerosol simulations from the Goddard Chemistry Aerosol Radiation Transport (GOCART) model and aerosol optical depth (AOD) measurements from the MODerate resolution Imaging Spectroradiometer (MODIS). The CALIPSO observations of geographical patterns and seasonal variations of AOD are generally consistent with GOCART simulations and MODIS retrievals especially near source regions, while the magnitude of AOD shows large discrepancies in most regions. Both the CALIPSO observation and GOCART model show that the aerosol extinction scale heights in major dust and smoke source regions are generally higher than that in industrial pollution source regions. The CALIPSO aerosol lidar ratio also generally agrees with GOCART model within 30% on regional scales. Major differences between satellite observations and GOCART model are identified, including (1) an underestimate of aerosol extinction by GOCART over the Indian sub-continent, (2) much larger aerosol extinction calculated by GOCART than observed by CALIPSO in dust source regions, (3) much weaker in magnitude and more concentrated aerosol in the lower atmosphere in CALIPSO observation than GOCART model over transported areas in midlatitudes, and (4) consistently lower aerosol scale height by CALIPSO observation than GOCART model. Possible factors contributing to these differences are discussed.
Owens, Kailey M; Marvin, Monica L; Gelehrter, Thomas D; Ruffin, Mack T; Uhlmann, Wendy R
2011-10-01
This study examined medical students' and house officers' opinions about the Surgeon General's "My Family Health Portrait" (MFHP) tool. Participants used the tool and were surveyed about tool mechanics, potential clinical uses, and barriers. None of the 97 participants had previously used this tool. The average time to enter a family history was 15 min (range 3 to 45 min). Participants agreed or strongly agreed that the MFHP tool is understandable (98%), easy to use (93%), and suitable for general public use (84%). Sixty-seven percent would encourage their patients to use the tool; 39% would ensure staff assistance. Participants would use the tool to identify patients at increased risk for disease (86%), record family history in the medical chart (84%), recommend preventive health behaviors (80%), and refer to genetics services (72%). Concerns about use of the tool included patient access, information accuracy, technical challenges, and the need for physician education on interpreting family history information.
NASA Astrophysics Data System (ADS)
Buss, S.; Wernli, H.; Peter, T.; Kivi, R.; Bui, T. P.; Kleinböhl, A.; Schiller, C.
Stratospheric winter temperatures play a key role in the chain of microphysical and chemical processes that lead to the formation of polar stratospheric clouds (PSCs), chlorine activation and eventually to stratospheric ozone depletion. Here the tempera- ture conditions during the Arctic winters 1999/2000 and 2000/2001 are quantitatively investigated using observed profiles of water vapour and nitric acid, and tempera- tures from high-resolution radiosondes and aircraft observations, global ECMWF and UKMO analyses and mesoscale model simulations over Scandinavia and Greenland. The ECMWF model resolves parts of the gravity wave activity and generally agrees well with the observations. However, for the very cold temperatures near the ice frost point the ECMWF analyses have a warm bias of 1-6 K compared to radiosondes. For the mesoscale model HRM, this bias is generally reduced due to a more accurate rep- resentation of gravity waves. Quantitative estimates of the impact of the mesoscale temperature perturbations indicates that over Scandinavia and Greenland the wave- induced stratospheric cooling (as simulated by the HRM) affects only moderately the estimated chlorine activation and homogeneous NAT particle formation, but strongly enhances the potential for ice formation.
Emerson, Douglas G.
1994-01-01
A model that simulates heat and water transfer in soils during freezing and thawing periods was developed and incorporated into the U.S. Geological Survey's Precipitation-Runoff Modeling System. The model's transfer of heat is based on an equation developed from Fourier's equation for heat flux. The model's transfer of water within the soil profile is based on the concept of capillary forces. Field capacity and infiltration rate can vary throughout the freezing and thawing period, depending on soil conditions and rate and timing of snowmelt. The model can be used to determine the effects of seasonally frozen soils on ground-water recharge and surface-water runoff. Data collected for two winters, 1985-86 and 1986-87, on three runoff plots were used to calibrate and verify the model. The winter of 1985-86 was colder than normal, and snow cover was continuous throughout the winter. The winter of 1986-87 was warmer than normal, and snow accumulated for only short periods of several days. as the criteria for determining the degree of agreement between simulated and measured data. The model was calibrated using the 1985-86 data for plot 2. The calibration simulation agreed closely with the measured data. The verification simulations for plots 1 and 3 using the 1985-86 data and for plots 1 and 2 using the 1986-87 data agreed closely with the measured data. The verification simulation for plot 3 using the 1986-87 data did not agree closely. The recalibration simulations for plots 1 and 3 using the 1985-86 data indicated little improvement because the verification simulations for plots 1 and 3 already agreed closely with the measured data.
Measuring the Effectiveness of a Genetic Counseling Supervision Training Conference.
Atzinger, Carrie L; He, Hua; Wusik, Katie
2016-08-01
Genetic counselors who receive formal training report increased confidence and competence in their supervisory roles. The effectiveness of specific formal supervision training has not been assessed previously. A day-long GC supervision conference was designed based on published supervision competencies and was attended by 37 genetic counselors. Linear Mixed Model and post-hoc paired t-test was used to compare Psychotherapy Supervisor Development Scale (PSDS) scores among/between individuals pre and post conference. Generalized Estimating Equation (GEE) model and post-hoc McNemar's test was used to determine if the conference had an effect on GC supervision competencies. PSDS scores were significantly increased 1 week (p < 0.001) and 6 months (p < 0.001) following the conference. For three supervision competencies, attendees were more likely to agree they were able to perform them after the conference than before. These effects remained significant 6 months later. For the three remaining competencies, the majority of supervisors agreed they could perform these before the conference; therefore, no change was found. This exploratory study showed this conference increased the perceived confidence and competence of the supervisors who attended and increased their self-reported ability to perform certain supervision competencies. While still preliminary, this supports the idea that a one day conference on supervision has the potential to impact supervisor development.
Pore-scale modeling of saturated permeabilities in random sphere packings.
Pan, C; Hilpert, M; Miller, C T
2001-12-01
We use two pore-scale approaches, lattice-Boltzmann (LB) and pore-network modeling, to simulate single-phase flow in simulated sphere packings that vary in porosity and sphere-size distribution. For both modeling approaches, we determine the size of the representative elementary volume with respect to the permeability. Permeabilities obtained by LB modeling agree well with Rumpf and Gupte's experiments in sphere packings for small Reynolds numbers. The LB simulations agree well with the empirical Ergun equation for intermediate but not for small Reynolds numbers. We suggest a modified form of Ergun's equation to describe both low and intermediate Reynolds number flows. The pore-network simulations agree well with predictions from the effective-medium approximation but underestimate the permeability due to the simplified representation of the porous media. Based on LB simulations in packings with log-normal sphere-size distributions, we suggest a permeability relation with respect to the porosity, as well as the mean and standard deviation of the sphere diameter.
77 FR 7537 - Suspension of Community Eligibility
Federal Register 2010, 2011, 2012, 2013, 2014
2012-02-13
... insurance that is not otherwise generally available from private insurers. In return, communities agree to... April 16, 1974, Emerg; ......do Do. County. May 19, 1981, Reg; February 16, 2012, Susp. Saint Cloud...
ERIC Educational Resources Information Center
Comptroller General of the U.S., Washington, DC.
This report provides comments from the General Accounting Office (GAO) on recommendations contained in the National Performance Review's (NPR) September 7, 1993, report which addressed ways to make the government work better and cost less. Generally, the GAO agrees with most of the NPR's recommendations and believes that successful implementation…
Stringy Gravity: Solving the Dark Problems at `short' distance
NASA Astrophysics Data System (ADS)
Park, Jeong-Hyuck
2018-01-01
Dictated by Symmetry Principle, string theory predicts not General Relativity but its own gravity which assumes the entire closed string massless sector to be geometric and thus gravitational. In terms of R/(MG), i.e. the dimensionless radial variable normalized by mass, Stringy Gravity agrees with General Relativity toward infinity, but modifies it at short distance. At far short distance, gravitational force can be even repulsive. These may solve the dark matter and energy problems, as they arise essentially from small R/(MG) observations: long distance divided by much heavier mass. We address the pertinent differential geometry for Stringy Gravity, stringy Equivalence Principle, stringy geodesics and the minimal coupling to the Standard Model. We highlight the notion of `doubled-yet-gauged' coordinate system, in which a gauge orbit corresponds to a single physical point and proper distance is defined between two gauge orbits by a path integral.
Analytical Solution of Displacements Around Circular Openings in Generalized Hoek-Brown Rocks
NASA Astrophysics Data System (ADS)
Huang, Houxu; Li, Jie; Wei, Jiuqi
2017-09-01
The rock in plastic region is divided into numbers of elements by the slip lines, resulted from shear localization. During the deformation process, the elements will slip along the slip lines and the displacement field is discontinuous. Slip lines around circular opening in isotropic rock, subjected to hydrostatic stress are described by the logarithmic spirals. Deformation of the plastic region is mainly attributed to the slippage. Relationship between the shear stresses and slippage on slip lines is presented, based on the study of Revuzhenko and Shemyakin. Relations between slippage and rock failure are described, based on the elastic-brittle-plastic model. An analytical solution is presented for the plane strain analysis of displacements around circular openings in the Generalized Hoek-Brown rock. With properly choosing of slippage parameters, results obtained by using the proposed solution agree well with those presented in published sources.
NASA Technical Reports Server (NTRS)
Bacmeister, Julio T.; Suarez, Max J.; Einaudi, Franco (Technical Monitor)
2001-01-01
This is the first of a two part study examining the connection of the equatorial momentum budget in an AGCM (Atmospheric General Circulation Model), with simulated equatorial surface wind stresses over the Pacific. The AGCM used in this study forms part of a newly developed coupled forecasting system used at NASA's Seasonal- to-Interannual Prediction Project. Here we describe the model and present results from a 20-year (1979-1999) AMIP-type experiment forced with observed SSTs (Sea Surface Temperatures). Model results are compared them with available observational data sets. The climatological pattern of extra-tropical planetary waves as well as their ENSO-related variability is found to agree quite well with re-analysis estimates. The model's surface wind stress is examined in detail, and reveals a reasonable overall simulation of seasonal interannual variability, as well as seasonal mean distributions. However, an excessive annual oscillation in wind stress over the equatorial central Pacific is found. We examine the model's divergent circulation over the tropical Pacific and compare it with estimates based on re-analysis data. These comparisons are generally good, but reveal excessive upper-level convergence in the central Pacific. In Part II of this study a direct examination of individual terms in the AGCM's momentum budget is presented. We relate the results of this analysis to the model's simulation of surface wind stress.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Munaò, Gianmarco, E-mail: gmunao@unime.it; Costa, Dino; Caccamo, Carlo
We investigate thermodynamic properties of anisotropic colloidal dumbbells in the frameworks provided by the Reference Interaction Site Model (RISM) theory and an Optimized Perturbation Theory (OPT), this latter based on a fourth-order high-temperature perturbative expansion of the free energy, recently generalized to molecular fluids. Our model is constituted by two identical tangent hard spheres surrounded by square-well attractions with same widths and progressively different depths. Gas-liquid coexistence curves are obtained by predicting pressures, free energies, and chemical potentials. In comparison with previous simulation results, RISM and OPT agree in reproducing the progressive reduction of the gas-liquid phase separation as themore » anisotropy of the interaction potential becomes more pronounced; in particular, the RISM theory provides reasonable predictions for all coexistence curves, bar the strong anisotropy regime, whereas OPT performs generally less well. Both theories predict a linear dependence of the critical temperature on the interaction strength, reproducing in this way the mean-field behavior observed in simulations; the critical density—that drastically drops as the anisotropy increases—turns to be less accurate. Our results appear as a robust benchmark for further theoretical studies, in support to the simulation approach, of self-assembly in model colloidal systems.« less
Code of Federal Regulations, 2011 CFR
2011-10-01
... cited as a cause for debarment to the attention of the appropriate Government agency in a timely manner... administrative action. (5) Whether the contractor has paid or has agreed to pay all criminal, civil, and...
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2012-10-01
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2014-10-01
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2013-10-01
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Singh, Kavita; Brodish, Paul; Mbai, Fiona; Kingola, Nzioki; Rinyuri, Agnes; Njeru, Carol; Mureithi, Patrick; Sambisa, William; Weir, Sharon
2014-01-01
A venue-based HIV prevention study which included Voluntary Counseling and Testing (VCT) was conducted in three diverse areas of Kenya— Malindi, Nanyuki and Rachounyo. Aims of the study were to: 1) assess the acceptability of VCT for the general population, men who have sex with men (MSM), and injecting drug users (IDUs) within the context of a venue-based approach; 2) determine if there were differences between those agreeing and not agreeing to testing; and 3) study factors associated with being HIV positive. Approximately 98% of IDUs and 97% of MSM agreed to VCT, providing evidence that populations with little access to services and whose behaviors are stigmatized and often considered illegal in their countries can be reached with needed HIV prevention services. Acceptability of VCT in the general population ranged from 60% in Malindi to 48% in Nanyuki. There were a few significant differences between those accepting and declining testing. Notably in Rachuonyo and Malindi those reporting multiple partners were more likely to accept testing. There was also evidence that riskier sexual behavior was associated with being HIV positive for both men in Rachounyo and women in Malindi. Overall HIV prevalence was higher among the individuals in this study compared to individuals sampled in the 2008–2009 Kenya Demographic and Health Survey, indicating the method is an appropriate means to reach the highest risk individuals including stigmatized populations. PMID:22198312
Presenting an Evaluation Model for the Cancer Registry Software.
Moghaddasi, Hamid; Asadi, Farkhondeh; Rabiei, Reza; Rahimi, Farough; Shahbodaghi, Reihaneh
2017-12-01
As cancer is increasingly growing, cancer registry is of great importance as the main core of cancer control programs, and many different software has been designed for this purpose. Therefore, establishing a comprehensive evaluation model is essential to evaluate and compare a wide range of such software. In this study, the criteria of the cancer registry software have been determined by studying the documents and two functional software of this field. The evaluation tool was a checklist and in order to validate the model, this checklist was presented to experts in the form of a questionnaire. To analyze the results of validation, an agreed coefficient of %75 was determined in order to apply changes. Finally, when the model was approved, the final version of the evaluation model for the cancer registry software was presented. The evaluation model of this study contains tool and method of evaluation. The evaluation tool is a checklist including the general and specific criteria of the cancer registry software along with their sub-criteria. The evaluation method of this study was chosen as a criteria-based evaluation method based on the findings. The model of this study encompasses various dimensions of cancer registry software and a proper method for evaluating it. The strong point of this evaluation model is the separation between general criteria and the specific ones, while trying to fulfill the comprehensiveness of the criteria. Since this model has been validated, it can be used as a standard to evaluate the cancer registry software.
NASA Astrophysics Data System (ADS)
Wang, F.; Notaro, M.; Yu, Y.; Mao, J.; Shi, X.; Wei, Y.
2016-12-01
North (N.) African rainfall is characterized by dramatic interannual to decadal variability with serious socio-economic ramifications. The Sahel and West African Monsoon (WAM) region experienced a dramatic shift to persistent drought by the late 1960s, while the Horn of Africa (HOA) underwent drying since the 1990s. Large disagreementregarding the dominant oceanic drivers of N. African hydrologic variability exists among modeling studies, leading to notable spread in Sahel summer rainfall projections for this century among Coupled Model Intercomparison Project models. In order to gain a deeper understanding of the oceanic drivers of N. African rainfall and establish a benchmark for model evaluation, a statistical method, the multivariate Generalized Equilibrium Feedback Assessment, is validated and applied to observations and a control run from the Community Earth System Model (CESM). This study represents the first time that the dominant oceanic drivers of N. African rainfall were evaluated and systematically compared between observations and model simulations. CESM and the observations consistently agree that tropical oceanic modes are the dominant controls of N. African rainfall. During the monsoon season, CESM and observations agree that an anomalously warm eastern tropical Pacific shifts the Walker Circulation eastward, with its descending branch supporting Sahel drying. CESM and the observations concur that a warmer tropical eastern Atlantic favors a southward-shifted Intertropical Convergence Zone, which intensifies WAM monsoonal rainfall. An observed reduction in Sahel rainfall accompanies this enhanced WAM rainfall, yet is confined to the Atlantic in CESM. During the short rains, both observations and CESM indicate that a positive phase of tropical Indian Ocean dipole (IOD) mode [anomalously warm (cold) in western (eastern) Indian] enhances HOA rainfall. The observed IOD impacts are limited to the short rains, while the simulated impacts are year-round.
Lithospheric magnetic field modelling of the African continent
NASA Astrophysics Data System (ADS)
Hemant, K.; Maus, S.
2003-04-01
New magnetic satellite missions in low-earth orbit are providing increasingly accurate maps of the lithospheric magnetic field. These maps can be used to infer the geological structure of regions hidden by Phanerozoic cover, taking into account our knowledge of crustal structure from surface geology and seismic methods. A GIS based modelling technique has been developed to model the various geological units of the continents using the UNESCO geological map of the world, supported by background geological information from various sources. Geological units of each region are assigned a susceptibility value based on laboratory values of the constituent rock types. Then, using the 3SMAC seismic crustal structure, a vertically integrated susceptibility (VIS) model is computed at each point of the region. Starting with this VIS model, the total field anomaly is computed at an altitude of 400 km and compared with the MF2 lithospheric magnetic field model derived from CHAMP data. The modelling results of the Precambrian units of the West African cratons agree well with MF2. The anomaly in the Central African cratonic region also correlates well, although part of it is unaccounted for as yet. Furthermore, the anomalies over the Tanzanian craton and surrounding region agree very well. Most of the regions around the South African cratons are hidden by Phanerozoic cover, yet the results above the Kaapvaal craton and the southern Zimbabwe craton around the Limpopo belt show good correspondence with the observed anomaly map. The results also suggest a probable extension of the Precambrian units below the sediments of younger age. In general, the lower crust is likely to be more mafic than presumed in our current understanding of Central Africa. Deviations in the magnitude of the anomalies in some regions are likely to be due to incomplete seismic information in those regions. Thus, the thickness of crustal layers derived from magnetic anomalies for these locations may help to constrain future geophysical models in the less explored regions of Africa.
Are Canadian general surgery residents ready for the 80-hour work week? A nationwide survey
Sudarshan, Monisha; Hanna, Wael C.; Jamal, Mohammed H.; Nguyen, Lily H.P.; Fraser, Shannon A.
2012-01-01
Background The purpose of this study was to describe Canadian general surgery residents’ perceptions regarding potential implementation of work-hour restrictions. Methods An ethics review board–approved, Web-based survey was submitted to all Canadian general surgery residency programs between April and July 2009. Questions evaluated the perceived effects of an 80-hour work week on length of training, operative exposure, learning and lifestyle. We used the Fisher exact test to compare senior and junior residents’ responses. Results Of 360 residents, 158 responded (70 seniors and 88 juniors). Among them, 79% reported working 75–100 hours per week. About 74% of seniors believed that limiting their work hours would decrease their operative exposure; 43% of juniors agreed (p < 0.001). Both seniors and juniors thought limiting their work hours would improve their lifestyle (86% v. 96%, p = 0.12). Overall, 60% of residents did not believe limiting work hours would extend the length of their training. Regarding 24-hour call, 60% of juniors thought it was hazardous to their health; 30% of seniors agreed (p = 0.001). Both senior and junior residents thought abolishing 24-hour call would decrease their operative exposure (84% v. 70%, p = 0.21). Overall, 31% of residents supported abolishing 24-hour call. About 47% of residents (41% seniors, 51% juniors, p = 0.26) agreed with the adoption of the 80-hour work week. Conclusion There is a training-level based dichotomy of opinion among general surgery residents in Canada regarding the perceived effects of work hour restrictions. Both groups have voted against abolishing 24-hour call, and neither group strongly supports the implementation of the 80-hour work week. PMID:22269303
Are Canadian general surgery residents ready for the 80-hour work week? A nationwide survey.
Sudarshan, Monisha; Hanna, Wael C; Jamal, Mohammed H; Nguyen, Lily H P; Fraser, Shannon A
2012-02-01
The purpose of this study was to describe Canadian general surgery residents' perceptions regarding potential implementation of work-hour restrictions. An ethics review board-approved, Web-based survey was submitted to all Canadian general surgery residency programs between April and July 2009. Questions evaluated the perceived effects of an 80-hour work week on length of training, operative exposure, learning and lifestyle. We used the Fisher exact test to compare senior and junior residents' responses. Of 360 residents, 158 responded (70 seniors and 88 juniors). Among them, 79% reported working 75-100 hours per week. About 74% of seniors believed that limiting their work hours would decrease their operative exposure; 43% of juniors agreed (p < 0.001). Both seniors and juniors thought limiting their work hours would improve their lifestyle (86% v. 96%, p = 0.12). Overall, 60% of residents did not believe limiting work hours would extend the length of their training. Regarding 24-hour call, 60% of juniors thought it was hazardous to their health; 30% of seniors agreed (p = 0.001). Both senior and junior residents thought abolishing 24-hour call would decrease their operative exposure (84% v. 70%, p = 0.21). Overall, 31% of residents supported abolishing 24-hour call. About 47% of residents (41% seniors, 51%juniors, p = 0.26) agreed with the adoption of the 80-hour work week. There is a training-level based dichotomy of opinion among general surgery residents in Canada regarding the perceived effects of work hour restrictions. Both groups have voted against abolishing 24-hour call, and neither group strongly supports the implementation of the 80-hour work week.
Simultaneous anatomical sketching as learning by doing method of teaching human anatomy.
Noorafshan, Ali; Hoseini, Leila; Amini, Mitra; Dehghani, Mohammad-Reza; Kojuri, Javad; Bazrafkan, Leila
2014-01-01
Learning by lecture is a passive experience. Many innovative techniques have been presented to stimulate students to assume a more active attitude toward learning. In this study, simultaneous sketch drawing, as an interactive learning technique was applied to teach anatomy to the medical students. We reconstructed a fun interactive model of teaching anatomy as simultaneous anatomic sketching. To test the model's instruction effectiveness, we conducted a quasi- experimental study and then the students were asked to write their learning experiences in their portfolio, also their view was evaluated by a questionnaire. The results of portfolio evaluation revealed that students believed that this method leads to deep learning and understanding anatomical subjects better. Evaluation of the students' views on this teaching approach was showed that, more than 80% of the students were agreed or completely agreed with this statement that leaning anatomy concepts are easier and the class is less boring with this method. More than 60% of the students were agreed or completely agreed to sketch anatomical figures with professor simultaneously. They also found the sketching make anatomy more attractive and it reduced the time for learning anatomy. These number of students were agree or completely agree that the method help them learning anatomical concept in anatomy laboratory. More than 80% of the students found the simultaneous sketching is a good method for learning anatomy overall. Sketch drawing, as an interactive learning technique, is an attractive for students to learn anatomy.
Simultaneous anatomical sketching as learning by doing method of teaching human anatomy
Noorafshan, Ali; Hoseini, Leila; Amini, Mitra; Dehghani, Mohammad-Reza; Kojuri, Javad; Bazrafkan, Leila
2014-01-01
Objective: Learning by lecture is a passive experience. Many innovative techniques have been presented to stimulate students to assume a more active attitude toward learning. In this study, simultaneous sketch drawing, as an interactive learning technique was applied to teach anatomy to the medical students. Materials and Methods: We reconstructed a fun interactive model of teaching anatomy as simultaneous anatomic sketching. To test the model's instruction effectiveness, we conducted a quasi- experimental study and then the students were asked to write their learning experiences in their portfolio, also their view was evaluated by a questionnaire. Results: The results of portfolio evaluation revealed that students believed that this method leads to deep learning and understanding anatomical subjects better. Evaluation of the students’ views on this teaching approach was showed that, more than 80% of the students were agreed or completely agreed with this statement that leaning anatomy concepts are easier and the class is less boring with this method. More than 60% of the students were agreed or completely agreed to sketch anatomical figures with professor simultaneously. They also found the sketching make anatomy more attractive and it reduced the time for learning anatomy. These number of students were agree or completely agree that the method help them learning anatomical concept in anatomy laboratory. More than 80% of the students found the simultaneous sketching is a good method for learning anatomy overall. Conclusion: Sketch drawing, as an interactive learning technique, is an attractive for students to learn anatomy. PMID:25013843
Weidmann, Anita Elaine; Cunningham, Scott; Gray, Gwen; Hansford, Denise; Bermano, Giovanna; Stewart, Derek
2012-04-01
Obesity has reached pandemic levels, with more than 1.5 billion adults being affected worldwide. In Scotland two-thirds of men and more than half of women are either overweight or obese, placing Scotland overall third behind the United States of America and Mexico. All community pharmacies in Scotland are contracted to provide public health services such as smoking cessation and there is increasing interest in their contribution to weight management. Researching this area in Scotland may provide valuable information to facilitate the development of community pharmacy services in other parts of the UK and internationally. To describe the views of the Scottish general public on the provision of weight management services via community pharmacies. General public in Scotland. A cross-sectional postal questionnaire survey of 6,000 randomly selected members of the Scottish general public aged 18 years and over. Views on community pharmacy led weight management services. Questionnaires were returned by 20.6% (n = 1,236). Over half 60.1% (n = 751) agreed or strongly agreed that they had easy access to pharmacy services in general and around one-third agreed (35%; n = 438) that it was more convenient to obtain weight management advice from a pharmacist than it is to make an appointment with a GP. Most respondents however lacked awareness of the types of health services available through community pharmacy (13.2%; n = 162) and would not feel comfortable speaking to a pharmacist or medicines counter assistant about weight related issues (25%; n = 320). Concerns over privacy (47.3%; n = 592) and perceived lack of pharmacists' specialist knowledge (open comments) were identified as potential barriers to service uptake by the general public. Overall, respondents appear to be receptive to the idea of accessing weight management services through community pharmacy but a perceived lack of privacy, poor knowledge of pharmacists' skill level and of public health services available to them may explain the reluctance in the uptake of such services to date. The general public's views expressed in this study may help to shape future community pharmacy led weight management service provision.
A Probabilistic Approach to Model Update
NASA Technical Reports Server (NTRS)
Horta, Lucas G.; Reaves, Mercedes C.; Voracek, David F.
2001-01-01
Finite element models are often developed for load validation, structural certification, response predictions, and to study alternate design concepts. In rare occasions, models developed with a nominal set of parameters agree with experimental data without the need to update parameter values. Today, model updating is generally heuristic and often performed by a skilled analyst with in-depth understanding of the model assumptions. Parameter uncertainties play a key role in understanding the model update problem and therefore probabilistic analysis tools, developed for reliability and risk analysis, may be used to incorporate uncertainty in the analysis. In this work, probability analysis (PA) tools are used to aid the parameter update task using experimental data and some basic knowledge of potential error sources. Discussed here is the first application of PA tools to update parameters of a finite element model for a composite wing structure. Static deflection data at six locations are used to update five parameters. It is shown that while prediction of individual response values may not be matched identically, the system response is significantly improved with moderate changes in parameter values.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lacagnina, Carlo; Hasekamp, Otto P.; Bian, Huisheng
2015-09-27
The aerosol Single Scattering Albedo (SSA) over the global oceans is evaluated based on polarimetric measurements by the PARASOL satellite. The retrieved values for SSA and Aerosol Optical Depth (AOD) agree well with the ground-based measurements of the AErosol RObotic NETwork (AERONET). The global coverage provided by the PARASOL observations represents a unique opportunity to evaluate SSA and AOD simulated by atmospheric transport model runs, as performed in the AeroCom framework. The SSA estimate provided by the AeroCom models is generally higher than the SSA retrieved from both PARASOL and AERONET. On the other hand, the mean simulated AOD ismore » about right or slightly underestimated compared with observations. An overestimate of the SSA by the models would suggest that these simulate an overly strong aerosol radiative cooling at top-of-atmosphere (TOA) and underestimate it at surface. This implies that aerosols have a potential stronger impact within the atmosphere than currently simulated.« less
FLRW cosmological models with quark and strange quark matters in f(R,T) gravity
NASA Astrophysics Data System (ADS)
Nagpal, Ritika; Singh, J. K.; Aygün, S.
2018-06-01
In this paper, we have studied the magnetized quark matter (QM) and strange quark matter (SQM) distributions in the presence of f(R,T) gravity in the background of Friedmann-Lemaître-Robertson-Walker (FLRW) metric. To get exact solutions of modified field equations we have used f(R,T ) = R + 2 f(T) model given by Harko et al. with two different parametrization of geometrical parameters i.e. the parametrization of the deceleration parameter q , and the scale factor a in hybrid expansion form. Also, we have obtained Einstein Static Universe (ESU) solutions for QM and SQM distributions in f(R,T) gravity and General Relativity (GR). All models in f(R,T) gravity and GR for FRW and ESU Universes with QM also SQM distributions, we get zero magnetic field. These results agree with the solutions of Aktaş and Aygün in f(R,T) gravity. However, we have also discussed the physical consequences of our obtained models.
Fluid Structure Interaction Analysis on Sidewall Aneurysm Models
NASA Astrophysics Data System (ADS)
Hao, Qing
2016-11-01
Wall shear stress is considered as an important factor for cerebral aneurysm growth and rupture. The objective of present study is to evaluate wall shear stress in aneurysm sac and neck by a fluid-structure-interaction (FSI) model, which was developed and validated against the particle image velocimetry (PIV) data. In this FSI model, the flow characteristics in a straight tube with different asymmetric aneurysm sizes over a range of Reynolds numbers from 200 to 1600 were investigated. The FSI results agreed well with PIV data. It was found that at steady flow conditions, when Reynolds number above 700, one large recirculating vortex would be formed, occupying the entire aneurysm sac. The center of the vortex is located at region near to the distal neck. A pair of counter rotating vortices would however be formed at Reynolds number below 700. Wall shear stresses reached highest level at the distal neck of the aneurysmal sac. The vortex strength, in general, is stronger at higher Reynolds number. Fluid Structure Interaction Analysis on Sidewall Aneurysm Models.
NASA Astrophysics Data System (ADS)
Shinozuka, Yuzo; Oda, Masato
2015-09-01
The interacting quasi-band model proposed for electronic states in simple alloys is extended for compound semiconductor alloys with general lattice structures containing several atoms per unit cell. Using a tight-binding model, a variational electronic wave function for quasi-Bloch states yields a non-Hermitian Hamiltonian matrix characterized by matrix elements of constituent crystals and concentration of constituents. Solving secular equations for each k-state yields the alloy’s energy spectrum for any type of randomness and arbitrary concentration. The theory is used to address III-V (II-VI) alloys with a zincblende lattice with crystal band structures well represented by the sp3s* model. Using the resulting 15 × 15 matrix, the concentration dependence of valence and conduction bands is calculated in a unified scheme for typical alloys: Al1-xGaxAs, GaAs1-xPx, and GaSb1-xPx. Results agree well with experiments and are discussed with respect to the concentration dependence, direct-indirect gap transition, and band-gap-bowing origin.
NASA Astrophysics Data System (ADS)
Khe, A. K.; Cherevko, A. A.; Chupakhin, A. P.; Bobkova, M. S.; Krivoshapkin, A. L.; Orlov, K. Yu
2016-06-01
In this paper a computer simulation of a blood flow in cerebral vessels with a giant saccular aneurysm at the bifurcation of the basilar artery is performed. The modelling is based on patient-specific clinical data (both flow domain geometry and boundary conditions for the inlets and outlets). The hydrodynamic and mechanical parameters are calculated in the frameworks of three models: rigid-wall assumption, one-way FSI approach, and full (two-way) hydroelastic model. A comparison of the numerical solutions shows that mutual fluid- solid interaction can result in qualitative changes in the structure of the fluid flow. Other characteristics of the flow (pressure, stress, strain and displacement) qualitatively agree with each other in different approaches. However, the quantitative comparison shows that accounting for the flow-vessel interaction, in general, decreases the absolute values of these parameters. Solving of the hydroelasticity problem gives a more detailed solution at a cost of highly increased computational time.
Wetting of crystalline polymer surfaces: A molecular dynamics simulation
NASA Astrophysics Data System (ADS)
Fan, Cun Feng; Caǧin, Tahir
1995-11-01
Molecular dynamics has been used to study the wetting of model polymer surfaces, the crystal surfaces of polyethylene (PE), poly(tetrafluoroethylene) (PTFE), and poly(ethylene terephthalate) (PET) by water and methylene iodide. In the simulation a liquid droplet is placed on a model surface and constant temperature, rigid body molecular dynamics is carried out while the model surface is kept fixed. A generally defined microscopic contact angle between a liquid droplet and a solid surface is quantitatively calculated from the volume of the droplet and the interfacial area between the droplet and the surface. The simulation results agree with the trend in experimental data for both water and methylene iodide. The shape of the droplets on the surface is analyzed and no obvious anisotropy of the droplets is seen in the surface plane, even though the crystal surfaces are highly oriented. The surface free energies of the model polymer surfaces are estimated from their contact angles with the two different liquid droplets.
Long History of IAM Comparisons
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, Steven J.; Clarke, Leon E.; Edmonds, James A.
2015-04-23
Correspondence to editor: We agree with the editors that the assumptions behind models of all types, including integrated assessment models (IAMs), should be as transparent as possible. The editors were in error, however, when they implied that the IAM community is just “now emulating the efforts of climate researchers by instigating their own model inter-comparison projects (MIPs).” In fact, model comparisons for integrated assessment and climate models followed a remarkably similar trajectory. Early General Circulation Model (GCM) comparison efforts, evolved to the first Atmospheric Model Inter-comparison Project (AMIP), which was initiated in the early 1990s. Atmospheric models evolved to coupledmore » atmosphere-ocean models (AOGCMs) and results from the first Coupled Model Inter-Comparison Project (CMIP1) become available about a decade later. Results of first energy model comparison exercise, conducted under the auspices of the Stanford Energy Modeling Forum, were published in 1977. A summary of the first comparison focused on climate change was published in 1993. As energy models were coupled to simple economic and climate models to form IAMs, the first comparison exercise for IAMs (EMF-14) was initiated in 1994, and IAM comparison exercises have been on-going since this time.« less
Hoddinott, Pat; Morgan, Heather; MacLennan, Graeme; Sewel, Kate; Thomson, Gill; Bauld, Linda; Yi, Deokhee; Ludbrook, Anne; Campbell, Marion K
2014-01-01
Objective To survey public attitudes about incentives for smoking cessation in pregnancy and for breast feeding to inform trial design. Design Cross-sectional survey. Setting and participants British general public. Methods Seven promising incentive strategies had been identified from evidence syntheses and qualitative interview data from service users and providers. These were shopping vouchers for: (1) validated smoking cessation in pregnancy and (2) after birth; (3) for a smoke-free home; (4) for proven breast feeding; (5) a free breast pump; (6) payments to health services for reaching smoking cessation in pregnancy targets and (7) breastfeeding targets. Ipsos MORI used area quota sampling and home-administered computer-assisted questionnaires, with randomised question order to assess agreement with different incentives (measured on a five-point scale). Demographic data and target behaviour experience were recorded. Analysis used multivariable ordered logit models. Results Agreement with incentives was mixed (ranging from 34% to 46%) among a representative sample of 1144 British adults. Mean agreement score was highest for a free breast pump, and lowest for incentives for smoking abstinence after birth. More women disagreed with shopping vouchers than men. Those with lower levels of education disagreed more with smoking cessation incentives and a breast pump. Those aged 44 or under agreed more with all incentive strategies compared with those aged 65 and over, particularly provider targets for smoking cessation. Non-white ethnic groups agreed particularly with breastfeeding incentives. Current smokers with previous stop attempts and respondents who had breast fed children agreed with providing vouchers for the respective behaviours. Up to £40/month vouchers for behaviour change were acceptable (>85%). Conclusions Women and the less educated were more likely to disagree, but men and women of childbearing age to agree, with incentives designed for their benefit. Trials evaluating reach, impact on health inequalities and ethnic groups are required prior to implementing incentive interventions. Trial registration number CRD42012001980. PMID:25037645
NASA Astrophysics Data System (ADS)
Khandu; Awange, Joseph L.; Anyah, Richard; Kuhn, Michael; Fukuda, Yoichi
2017-10-01
The Ganges-Brahmaputra-Meghna (GBM) River Basin presents a spatially diverse hydrological regime due to it's complex topography and escalating demand for freshwater resources. This presents a big challenge in applying the current state-of-the-art regional climate models (RCMs) for climate change impact studies in the GBM River Basin. In this study, several RCM simulations generated by RegCM4.4 and PRECIS are assessed for their seasonal and interannual variations, onset/withdrawal of the Indian monsoon, and long-term trends in precipitation and temperature from 1982 to 2012. The results indicate that in general, RegCM4.4 and PRECIS simulations appear to reasonably reproduce the mean seasonal distribution of precipitation and temperature across the GBM River Basin, although the two RCMs are integrated over a different domain size. On average, the RegCM4.4 simulations overestimate monsoon precipitation by {˜ }26 and {˜ }5% in the Ganges and Brahmaputra-Meghna River Basin, respectively, while PRECIS simulations underestimate (overestimate) the same by {˜ }7% ({˜ }16%). Both RegCM4.4 and PRECIS simulations indicate an intense cold bias (up to 10° C) in the Himalayas, and are generally stronger in the RegCM4.4 simulations. Additionally, they tend to produce high precipitation between April and May in the Ganges (RegCM4.4 simulations) and Brahmaputra-Meghna (PRECIS simulations) River Basins, resulting in early onset of the Indian monsoon in the Ganges River Basin. PRECIS simulations exhibit a delayed monsoon withdrawal in the Brahmaputra-Meghna River Basin. Despite large spatial variations in onset and withdrawal periods across the GBM River Basin, the basin-averaged results agree reasonably well with the observed periods. Although global climate model (GCM) driven simulations are generally poor in representing the interannual variability of precipitation and winter temperature variations, they tend to agree well with observed precipitation anomalies when driven by perfect boundary conditions. It is also seen that all GCM driven simulations feature significant positive surface temperature trends consistent with the observed datasets.
Advanced transportation system improvements for North Carolina's Piedmont Triad
DOT National Transportation Integrated Search
1994-07-01
Residents, transportation professionals, and decision-makers throughout the Piedmont : Triad generally agree that the prosperity of the region depends on having an adequate : transportation system. The ability to move people and goods quickly, effici...
Measuring Local Public Health and Primary Care Collaboration: A Practice-Based Research Approach.
Gyllstrom, Elizabeth; Gearin, Kimberly; Nease, Donald; Bekemeier, Betty; Pratt, Rebekah
2018-06-07
To describe the degree of public health and primary care collaboration at the local level and develop a model framework of collaboration, the Community Collaboration Health Model (CCHM). Mixed-methods, cross-sectional surveys, and semistructured, key informant interviews. All local health jurisdictions in Colorado, Minnesota, Washington, and Wisconsin. Leaders from each jurisdiction were identified to describe local collaboration. Eighty percent of local health directors completed our survey (n = 193), representing 80% of jurisdictions. The parallel primary care survey had a 31% response rate (n = 128), representing 50% of jurisdictions. Twenty pairs of local health directors and primary care leaders participated in key informant interviews. Thirty-seven percent of jurisdictions were classified as having strong foundational and energizing characteristics in the model. Ten percent displayed high energizing/low foundational characteristics, 11% had high foundational/low energizing characteristics, and 42% of jurisdictions were low on both. Respondents reported wide variation in relationship factors. They generally agreed that foundational characteristics were present in current working relationships but were less likely to agree that relationships had factors promoting sustainability or innovation. Both sectors valued working together in principle, yet few did. Identifying shared priorities and achieving tangible benefits may be critical to realizing sustained relationships resulting in population health improvement. Our study reveals broad variation in experiences among local jurisdictions in our sample. Tools, such as the CCHM, and technical assistance may be helpful to support advancing collaboration. Dedicated funding, reimbursement redesign, improved data systems, and data sharing capability are key components of promoting collaboration. Yet, even in the absence of new reimbursement models or funding mechanisms, there are steps leaders can take to build and sustain their relationships. The self-assessment tool and the CCHM can identify opportunities for improving collaboration and link practitioners to strategies.
Encoding and Retrieval Interference in Sentence Comprehension: Evidence from Agreement
Villata, Sandra; Tabor, Whitney; Franck, Julie
2018-01-01
Long-distance verb-argument dependencies generally require the integration of a fronted argument when the verb is encountered for sentence interpretation. Under a parsing model that handles long-distance dependencies through a cue-based retrieval mechanism, retrieval is hampered when retrieval cues also resonate with non-target elements (retrieval interference). However, similarity-based interference may also stem from interference arising during the encoding of elements in memory (encoding interference), an effect that is not directly accountable for by a cue-based retrieval mechanism. Although encoding and retrieval interference are clearly distinct at the theoretical level, it is difficult to disentangle the two on empirical grounds, since encoding interference may also manifest at the retrieval region. We report two self-paced reading experiments aimed at teasing apart the role of each component in gender and number subject-verb agreement in Italian and English object relative clauses. In Italian, the verb does not agree in gender with the subject, thus providing no cue for retrieval. In English, although present tense verbs agree in number with the subject, past tense verbs do not, allowing us to test the role of number as a retrieval cue within the same language. Results from both experiments converge, showing similarity-based interference at encoding, and some evidence for an effect at retrieval. After having pointed out the non-negligible role of encoding in sentence comprehension, and noting that Lewis and Vasishth’s (2005) ACT-R model of sentence processing, the most fully developed cue-based retrieval approach to sentence processing does not predict encoding effects, we propose an augmentation of this model that predicts these effects. We then also propose a self-organizing sentence processing model (SOSP), which has the advantage of accounting for retrieval and encoding interference with a single mechanism. PMID:29403414
Interplay of charge distribution and conformation in peptides: comparison of theory and experiment.
Makowska, Joanna; Bagińska, Katarzyna; Kasprzykowski, F; Vila, Jorge A; Jagielska, Anna; Liwo, Adam; Chmurzyński, Lech; Scheraga, Harold A
2005-01-01
We assessed the correlation between charge distribution and conformation of flexible peptides by comparing the theoretically calculated potentiometric-titration curves of two model peptides, Ac-Lys5-NHMe (a model of poly-L-lysine) and Ac-Lys-Ala11-Lys-Gly2-Tyr-NH2 (P1) in water and methanol, with the experimental curves. The calculation procedure consisted of three steps: (i) global conformational search of the peptide under study using the electrostatically driven Monte Carlo (EDMC) method with the empirical conformational energy program for peptides (ECEPP)/3 force field plus the surface-hydration (SRFOPT) or the generalized Born surface area (GBSA) solvation model as well as a molecular dynamics method with the assisted model building and energy refinement (AMBER)99/GBSA force field; (ii) reevaluation of the energy in the pH range considered by using the modified Poisson-Boltzmann approach and taking into account all possible protonation microstates of each conformation, and (iii) calculation of the average degree of protonation of the peptide at a given pH value by Boltzmann averaging over conformations. For Ac-Lys5-NHMe, the computed titration curve agrees qualitatively with the experimental curve of poly-L-lysine in 95% methanol. The experimental titration curves of peptide P1 in water and methanol indicate a remarkable downshift of the first pK(a) value compared to the values for reference compounds (n-butylamine and phenol, respectively), suggesting the presence of a hydrogen bond between the tyrosine hydroxyl oxygen and the H(epsilon) proton of a protonated lysine side chain. The theoretical titration curves agree well with the experimental curves, if conformations with such hydrogen bonds constitute a significant part of the ensemble; otherwise, the theory predicts too small a downward pH shift. Copyright 2005 Wiley Periodicals, Inc
Using MODFLOW drains to simulate groundwater flow in a karst environment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Quinn, J.; Tomasko, D.; Glennon, M.A.
1998-07-01
Modeling groundwater flow in a karst environment is both numerically challenging and highly uncertain because of potentially complex flowpaths and a lack of site-specific information. This study presents the results of MODFLOW numerical modeling in which drain cells in a finite-difference model are used as analogs for preferential flowpaths or conduits in karst environments. In this study, conduits in mixed-flow systems are simulated by assigning connected pathways of drain cells from the locations of tracer releases, sinkholes, or other karst features to outlet springs along inferred flowpaths. These paths are determined by the locations of losing stream segments, ephemeral streammore » beds, geophysical surveys, fracture lineaments, or other surficial characteristics, combined with the results of dye traces. The elevations of the drains at the discharge ends of the inferred flowpaths are estimated from field data and are adjusted when necessary during model calibration. To simulate flow in a free-flowing conduit, a high conductance is assigned to each drain to eliminate the need for drain-specific information that would be very difficult to obtain. Calculations were performed for a site near Hohenfels, Germany. The potentiometric surface produced by the simulations agreed well with field data. The head contours in the vicinity of the karst features behaved in a manner consistent with a flow system having both diffuse and conduit components, and the sum of the volumetric flow out of the drain cells agreed closely with spring discharges and stream flows. Because of the success of this approach, it is recommended for regional studies in which little site-specific information (e.g., location, number, size, and conductivity of fractures and conduits) is available, and general flow characteristics are desired.« less
NASA Technical Reports Server (NTRS)
Wang, Qunzhen; Mathias, Edward C.; Heman, Joe R.; Smith, Cory W.
2000-01-01
A new, thermal-flow simulation code, called SFLOW. has been developed to model the gas dynamics, heat transfer, as well as O-ring and flow path erosion inside the space shuttle solid rocket motor joints by combining SINDA/Glo, a commercial thermal analyzer. and SHARPO, a general-purpose CFD code developed at Thiokol Propulsion. SHARP was modified so that friction, heat transfer, mass addition, as well as minor losses in one-dimensional flow can be taken into account. The pressure, temperature and velocity of the combustion gas in the leak paths are calculated in SHARP by solving the time-dependent Navier-Stokes equations while the heat conduction in the solid is modeled by SINDA/G. The two codes are coupled by the heat flux at the solid-gas interface. A few test cases are presented and the results from SFLOW agree very well with the exact solutions or experimental data. These cases include Fanno flow where friction is important, Rayleigh flow where heat transfer between gas and solid is important, flow with mass addition due to the erosion of the solid wall, a transient volume venting process, as well as some transient one-dimensional flows with analytical solutions. In addition, SFLOW is applied to model the RSRM nozzle joint 4 subscale hot-flow tests and the predicted pressures, temperatures (both gas and solid), and O-ring erosions agree well with the experimental data. It was also found that the heat transfer between gas and solid has a major effect on the pressures and temperatures of the fill bottles in the RSRM nozzle joint 4 configuration No. 8 test.
NASA Technical Reports Server (NTRS)
Webster, Christopher R.; May, Randy D.
1987-01-01
Simultaneous in situ measurements of temperature, pressure, and the NO, NO2, O3, jNO2, CH4, H2O, and CO2 concentrations were conducted in the 40- to 26-km region of the stratosphere using the JPL Balloon-borne Laser In Situ Sensor, a tunable diode laser absorption spectrometer. The NO, NO2, CH4, H2O, and CO2 concentration measurements generally show good agreement with previous observations, with a tendency for somewhat lower NO2 amounts. Measured O3 concentrations at 38 km agree well with comparable measurements from in situ UV photometers, but at 28 km they are lower by about 10 percent and agree more closely with the solar backscattered UV data. A decline was found in NO2 during the night over a 5-km altitude range, which implies either lower NO2 postsunset profiles, or an NO2 decay rate that is significantly higher than current model predictions that use N2O5 chemistry.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Makufa, R; Bvochora-Nsingo, M; Karumekayi, T
2016-06-15
Purpose: The global burden of cancer is considerable, particularly in low and middle-income countries. Massachusetts General Hospital (MGH) and Botswana-Harvard AIDS Institute have partnered with the oncology community and government of Botswana to form BOTSOGO (BOTSwana Oncology Global Outreach) to address the rising burden of cancer in Botswana. Currently, radiation therapy (RT) is only available at a single linear accelerator (LINAC) in Gaborone Private Hospital (GPH). BOTSOGO worked to limit the absence of RT during a LINAC upgrade and ensure a safe transition to modern radiotherapy techniques. Methods: The existing Elekta Precise LINAC was decommissioned in November 2015 and replacedmore » with a new Elekta VERSA-HD with IMRT/VMAT/CBCT capability. Upgraded treatment planning and record-and-verify systems were also installed. Physicists from GPH and MGH collaborated during an intensive on-site visit in Botswana during the commissioning process. Measurements were performed using newly purchased Sun Nuclear equipment. Photon beams were matched with an existing model to minimize the time needed for beam modeling and machine down time. Additional remote peer review was also employed. Independent dosimetry was performed by irradiating OSLDs, which were subsequently analyzed at MGH. Results: Photon beam quality agreed with reference data within 0.2%. Electron beam data agreed with example clinical data within 3%. Absolute dose calibration was performed using both IAEA and AAPM protocols. Absolute dose measurements with OSLDs agreed within 5%. Quentry cloud-based software was installed to facilitate remote review of treatment plans. Patient treatments resumed in February 2016. The time without RT was reduced, therefore likely resulting in reduced patient morbidity/mortality. Conclusion: A global physics collaboration was utilized to commission a modern LINAC in a resource-constrained setting. This can be a useful model in other areas with limited resources. Further use of technology and on-site exchanges will facilitate the introduction of more advanced techniques in Botswana. We acknowledge funding support from the AAPM International Educational Activities Committee and the NCI Federal Share Proton Beam Program Income Grant.« less
Open-path, closed-path and reconstructed aerosol extinction at a rural site.
Gordon, Timothy D; Prenni, Anthony J; Renfro, James R; McClure, Ethan; Hicks, Bill; Onasch, Timothy B; Freedman, Andrew; McMeeking, Gavin R; Chen, Ping
2018-04-09
The Handix Scientific Open-Path Cavity Ringdown Spectrometer (OPCRDS) was deployed during summer 2016 in Great Smoky Mountains National Park (GRSM). Extinction coefficients from the relatively new OPCRDS and from a more well-established extinction instrument agreed to within 7%. Aerosol hygroscopic growth (f(RH)) was calculated from the ratio of ambient extinction measured by the OPCRDS to dry extinction measured by a closed-path extinction monitor (Aerodyne's Cavity Attenuated Phase Shift Particulate Matter Extinction Monitor, CAPS PMex). Derived hygroscopicity (RH < 95%) from this campaign agreed with data from 1995 at the same site and time of year, which is noteworthy given the decreasing trend for organics and sulfate in the eastern U.S. However, maximum f(RH) values in 1995 were less than half as large as those recorded in 2016-possibly due to nephelometer truncation losses in 1995. Two hygroscopicity parameterizations were investigated using high time resolution OPCRDS+CAPS PMex data, and the K ext model was more accurate than the γ model. Data from the two ambient optical instruments, the OPCRDS and the open-path nephelometer, generally agreed; however, significant discrepancies between ambient scattering and extinction were observed, apparently driven by a combination of hygroscopic growth effects, which tend to increase nephelometer truncation losses and decrease sensitivity to the wavelength difference between the two instruments as a function of particle size. There was not a statistically significant difference in the mean reconstructed extinction values obtained from the original and the revised IMPROVE (Interagency Monitoring of Protected Visual Environments) equations. On average IMPROVE reconstructed extinction was ~25% lower than extinction measured by the OPCRDS, which suggests that the IMPROVE equations and 24-hr aerosol data are moderately successful in estimating current haze levels at GRSM. However, this conclusion is limited by the coarse temporal resolution and the low dynamic range of the IMPROVE reconstructed extinction.
Emergence of Landauer transport from quantum dynamics: A model Hamiltonian approach
NASA Astrophysics Data System (ADS)
Pal, Partha Pratim; Ramakrishna, S.; Seideman, Tamar
2018-04-01
The Landauer expression for computing current-voltage characteristics in nanoscale devices is efficient but not suited to transient phenomena and a time-dependent current because it is applicable only when the charge carriers transition into a steady flux after an external perturbation. In this article, we construct a very general expression for time-dependent current in an electrode-molecule-electrode arrangement. Utilizing a model Hamiltonian (consisting of the subsystem energy levels and their electronic coupling terms), we propagate the Schrödinger wave function equation to numerically compute the time-dependent population in the individual subsystems. The current in each electrode (defined in terms of the rate of change of the corresponding population) has two components, one due to the charges originating from the same electrode and the other due to the charges initially residing at the other electrode. We derive an analytical expression for the first component and illustrate that it agrees reasonably with its numerical counterpart at early times. Exploiting the unitary evolution of a wavefunction, we construct a more general Landauer style formula and illustrate the emergence of Landauer transport from our simulations without the assumption of time-independent charge flow. Our generalized Landauer formula is valid at all times for models beyond the wide-band limit, non-uniform electrode density of states and for time and energy-dependent electronic coupling between the subsystems. Subsequently, we investigate the ingredients in our model that regulate the onset time scale of this steady state. We compare the performance of our general current expression with the Landauer current for time-dependent electronic coupling. Finally, we comment on the applicability of the Landauer formula to compute hot-electron current arising upon plasmon decoherence.
Emergence of Landauer transport from quantum dynamics: A model Hamiltonian approach.
Pal, Partha Pratim; Ramakrishna, S; Seideman, Tamar
2018-04-14
The Landauer expression for computing current-voltage characteristics in nanoscale devices is efficient but not suited to transient phenomena and a time-dependent current because it is applicable only when the charge carriers transition into a steady flux after an external perturbation. In this article, we construct a very general expression for time-dependent current in an electrode-molecule-electrode arrangement. Utilizing a model Hamiltonian (consisting of the subsystem energy levels and their electronic coupling terms), we propagate the Schrödinger wave function equation to numerically compute the time-dependent population in the individual subsystems. The current in each electrode (defined in terms of the rate of change of the corresponding population) has two components, one due to the charges originating from the same electrode and the other due to the charges initially residing at the other electrode. We derive an analytical expression for the first component and illustrate that it agrees reasonably with its numerical counterpart at early times. Exploiting the unitary evolution of a wavefunction, we construct a more general Landauer style formula and illustrate the emergence of Landauer transport from our simulations without the assumption of time-independent charge flow. Our generalized Landauer formula is valid at all times for models beyond the wide-band limit, non-uniform electrode density of states and for time and energy-dependent electronic coupling between the subsystems. Subsequently, we investigate the ingredients in our model that regulate the onset time scale of this steady state. We compare the performance of our general current expression with the Landauer current for time-dependent electronic coupling. Finally, we comment on the applicability of the Landauer formula to compute hot-electron current arising upon plasmon decoherence.
Emerson, Douglas G.
1991-01-01
A model that simulates heat and water transfer in soils during freezing and thawing periods was developed and incorporated into the U.S. Geological Survey's Precipitation-Runoff Modeling System. The transfer of heat 1s based on an equation developed from Fourier's equation for heat flux. Field capacity and infiltration rate can vary throughout the freezing and thawing period, depending on soil conditions and rate and timing of snowmelt. The transfer of water within the soil profile is based on the concept of capillary forces. The model can be used to determine the effects of seasonally frozen soils on ground-water recharge and surface-water runoff. Data collected for two winters, 1985-86 and 1986-87, on three runoff plots were used to calibrate and verify the model. The winter of 1985-86 was colder than normal and snow cover was continuous throughout the winter. The winter of 1986-87 was wanner than normal and snow accumulated for only short periods of several days.Runoff, snowmelt, and frost depths were used as the criteria for determining the degree of agreement between simulated and measured data. The model was calibrated using the 1985-86 data for plot 2. The calibration simulation agreed closely with the measured data. The verification simulations for plots 1 and 3 using the 1985-86 data and for plots 1 and 2 using the 1986-87 data agreed closely with the measured data. The verification simulation for plot 3 using the 1986-87 data did not agree closely. The recalibratlon simulations for plots 1 and 3 using the 1985-86 data Indicated small improvement because the verification simulations for plots 1 and 3 already agreed closely with the measured data.
Critical behavior and dimension crossover of pion superfluidity
NASA Astrophysics Data System (ADS)
Wang, Ziyue; Zhuang, Pengfei
2016-09-01
We investigate the critical behavior of pion superfluidity in the framework of the functional renormalization group (FRG). By solving the flow equations in the SU(2) linear sigma model at finite temperature and isospin density, and making comparison with the fixed point analysis of a general O (N ) system with continuous dimension, we find that the pion superfluidity is a second order phase transition subject to an O (2 ) universality class with a dimension crossover from dc=4 to dc=3 . This phenomenon provides a concrete example of dimension reduction in thermal field theory. The large-N expansion gives a temperature independent critical exponent β and agrees with the FRG result only at zero temperature.
NASA Technical Reports Server (NTRS)
Perry, B., III
1981-01-01
Comparisons are presented analytically predicted and experimental turbulence responses of a wind tunnel model of a DC-10 derivative wing equipped with an active control system. The active control system was designed for the purpose of flutter suppression, but it had additional benefit of alleviating gust loads (wing bending moment) by about 25%. Comparisions of various wing responses are presented for variations in active control system parameters and tunnel speed. The analytical turbulence responses were obtained using DYLOFLEX, a computer program for dynamic loads analyses of flexible airplanes with active controls. In general, the analytical predictions agreed reasonably well with the experimental data.
NASA Technical Reports Server (NTRS)
Chipperfield, M. P.; Liang, Q.; Strahan, S. E.; Morgenstern, O.; Dhomse, S. S.; Abraham, N. L.; Archibald, A. T.; Bekki, S.; Braesicke, P.; Di Genova, G.;
2014-01-01
We have diagnosed the lifetimes of long-lived source gases emitted at the surface and removed in the stratosphere using six three-dimensional chemistry-climate models and a two-dimensional model. The models all used the same standard photochemical data. We investigate the effect of different definitions of lifetimes, including running the models with both mixing ratio (MBC) and flux (FBC) boundary conditions. Within the same model, the lifetimes diagnosed by different methods agree very well. Using FBCs versus MBCs leads to a different tracer burden as the implied lifetime contained in the MBC value does not necessarily match a model's own calculated lifetime. In general, there are much larger differences in the lifetimes calculated by different models, the main causes of which are variations in the modeled rates of ascent and horizontal mixing in the tropical midlower stratosphere. The model runs have been used to compute instantaneous and steady state lifetimes. For chlorofluorocarbons (CFCs) their atmospheric distribution was far from steady state in their growth phase through to the 1980s, and the diagnosed instantaneous lifetime is accordingly much longer. Following the cessation of emissions, the resulting decay of CFCs is much closer to steady state. For 2100 conditions the model circulation speeds generally increase, but a thicker ozone layer due to recovery and climate change reduces photolysis rates. These effects compensate so the net impact on modeled lifetimes is small. For future assessments of stratospheric ozone, use of FBCs would allow a consistent balance between rate of CFC removal and model circulation rate
NASA Technical Reports Server (NTRS)
Chipperfield, M. P.; Liang, Q.; Strahan, S. E.; Morgenstern, O.; Dhomse, S. S.; Abraham, N. L.; Archibald, A. T.; Bekki, S.; Braesicke, P.; Di Genova, G.;
2014-01-01
We have diagnosed the lifetimes of long-lived source gases emitted at the surface and removed in the stratosphere using six three-dimensional chemistry-climate models and a two-dimensional model. The models all used the same standard photochemical data. We investigate the effect of different definitions of lifetimes, including running the models with both mixing ratio (MBC) and flux (FBC) boundary conditions. Within the same model, the lifetimes diagnosed by different methods agree very well. Using FBCs versus MBCs leads to a different tracer burden as the implied lifetime contained in theMBC value does not necessarilymatch a model's own calculated lifetime. In general, there are much larger differences in the lifetimes calculated by different models, the main causes of which are variations in the modeled rates of ascent and horizontal mixing in the tropical midlower stratosphere. The model runs have been used to compute instantaneous and steady state lifetimes. For chlorofluorocarbons (CFCs) their atmospheric distribution was far from steady state in their growth phase through to the 1980s, and the diagnosed instantaneous lifetime is accordingly much longer. Following the cessation of emissions, the resulting decay of CFCs is much closer to steady state. For 2100 conditions the model circulation speeds generally increase, but a thicker ozone layer due to recovery and climate change reduces photolysis rates. These effects compensate so the net impact on modeled lifetimes is small. For future assessments of stratospheric ozone, use of FBCs would allow a consistent balance between rate of CFC removal and model circulation rate.
Scale-model charge-transfer technique for measuring enhancement factors
NASA Technical Reports Server (NTRS)
Kositsky, J.; Nanevicz, J. E.
1991-01-01
Determination of aircraft electric field enhancement factors is crucial when using airborne field mill (ABFM) systems to accurately measure electric fields aloft. SRI used the scale model charge transfer technique to determine enhancement factors of several canonical shapes and a scale model Learjet 36A. The measured values for the canonical shapes agreed with known analytic solutions within about 6 percent. The laboratory determined enhancement factors for the aircraft were compared with those derived from in-flight data gathered by a Learjet 36A outfitted with eight field mills. The values agreed to within experimental error (approx. 15 percent).
SONOS Nonvolatile Memory Cell Programming Characteristics
NASA Technical Reports Server (NTRS)
MacLeod, Todd C.; Phillips, Thomas A.; Ho, Fat D.
2010-01-01
Silicon-oxide-nitride-oxide-silicon (SONOS) nonvolatile memory is gaining favor over conventional EEPROM FLASH memory technology. This paper characterizes the SONOS write operation using a nonquasi-static MOSFET model. This includes floating gate charge and voltage characteristics as well as tunneling current, voltage threshold and drain current characterization. The characterization of the SONOS memory cell predicted by the model closely agrees with experimental data obtained from actual SONOS memory cells. The tunnel current, drain current, threshold voltage and read drain current all closely agreed with empirical data.
a Model to Simulate the Radiative Transfer of Fluorescence in a Leaf
NASA Astrophysics Data System (ADS)
Zhao, F.; Ni, Q.
2018-04-01
Light is reflected, transmitted and absorbed by green leaves. Chlorophyll fluorescence (ChlF) is the signal emitted by chlorophyll molecules in the leaf after the absorption of light. ChlF can be used as a direct probe of the functional status of photosynthetic machinery because of its close relationship with photosynthesis. The scattering, absorbing, and emitting properties of leaves are spectrally dependent, which can be simulated by modeling leaf-level fluorescence. In this paper, we proposed a Monte-Carlo (MC) model to simulate the radiative transfer of photons in the leaf. Results show that typical leaf fluorescence spectra can be properly simulated, with two peaks centered at around 685 nm in the red and 740 nm in the far-red regions. By analysing the sensitivity of the input parameters, we found the MC model can well simulate their influence on the emitted fluorescence. Meanwhile we compared results simulated by MC model with those by the Fluspect model. Generally they agree well in the far-red region but deviate in the red region.
Extension of the quantum-kinetic model to lunar and Mars return physics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liechty, D. S.; Lewis, M. J.
The ability to compute rarefied, ionized hypersonic flows is becoming more important as missions such as Earth reentry, landing high-mass payloads on Mars, and the exploration of the outer planets and their satellites are being considered. A recently introduced molecular-level chemistry model, the quantum-kinetic, or Q-K, model that predicts reaction rates for gases in thermal equilibrium and non-equilibrium using only kinetic theory and fundamental molecular properties, is extended in the current work to include electronic energy level transitions and reactions involving charged particles. Like the Q-K procedures for neutral species chemical reactions, these new models are phenomenological procedures that aimmore » to reproduce the reaction/transition rates but do not necessarily capture the exact physics. These engineering models are necessarily efficient due to the requirement to compute billions of simulated collisions in direct simulation Monte Carlo (DSMC) simulations. The new models are shown to generally agree within the spread of reported transition and reaction rates from the literature for near equilibrium conditions.« less
Agerskov, Claus
2016-04-01
A neural network model is presented of novelty detection in the CA1 subdomain of the hippocampal formation from the perspective of information flow. This computational model is restricted on several levels by both anatomical information about hippocampal circuitry and behavioral data from studies done in rats. Several studies report that the CA1 area broadcasts a generalized novelty signal in response to changes in the environment. Using the neural engineering framework developed by Eliasmith et al., a spiking neural network architecture is created that is able to compare high-dimensional vectors, symbolizing semantic information, according to the semantic pointer hypothesis. This model then computes the similarity between the vectors, as both direct inputs and a recalled memory from a long-term memory network by performing the dot-product operation in a novelty neural network architecture. The developed CA1 model agrees with available neuroanatomical data, as well as the presented behavioral data, and so it is a biologically realistic model of novelty detection in the hippocampus, which can provide a feasible explanation for experimentally observed dynamics.
Peatlands through the Last Glacial Cycle: Evidence and Model Results
NASA Astrophysics Data System (ADS)
Kleinen, T.; Treat, C. C.; Brovkin, V.
2017-12-01
The spatiotemporal distribution of peatlands prior to the last glacial maxium (LGM) is largely unknown. However, some evidence of non-extant peatlands is available in the form of buried organic-rich sediments. We have undertaken a synthesis of these "buried" peatlands from > 1000 detailed stratigraphic descriptions and combined it with data on extant peatlands to derive a first global synthesis of global peatland extent through the last glacial cycle. We present results of this synthesis in combination with modeling results where we determined peatland extents and carbon stocks from a transient simulation of the last glacial cycle with the CLIMBER2-LPJ model. We show that peat has existed in boreal latitudes at all times since the last interglacial, that evidence for tropical peatlands exists for the last 50,000 yrs, and that the model results in general agree well with the collected evidence of past peatlands, allowing a first estimate of peat carbon stock changes through the last glacial cycle. We discuss data and model limitations, with a focus on requirements for improving model-based peatland estimates.
A telephone survey of cancer awareness among frontline staff: informing training needs
Cook, N; Hart, A; Nuttall, K; Simpson, K; Turnill, N; Grant-Pearce, C; Damms, P; Allen, V; Slade, K; Dey, P
2011-01-01
Background: Studies have shown limited awareness about cancer risk factors among hospital-based staff. Less is known about general cancer awareness among community frontline National Health Service and social care staff. Methods: A cross-sectional computer-assisted telephone survey of 4664 frontline community-based health and social care staff in North West England. Results: A total of 671 out of 4664 (14.4%) potentially eligible subjects agreed to take part. Over 92% of staff recognised most warning signs, except an unexplained pain (88.8%, n=596), cough or hoarseness (86.9%, n=583) and a sore that does not heal (77.3%, n=519). The bowel cancer-screening programme was recognised by 61.8% (n=415) of staff. Most staff agreed that smoking and passive smoking ‘increased the chance of getting cancer.' Fewer agreed about getting sunburnt more than once as a child (78.0%, n=523), being overweight (73.5%, n=493), drinking more than one unit of alcohol per day (50.2%, n=337) or doing less than 30 min of moderate physical exercise five times a week (41.1%, n=276). Conclusion: Cancer awareness is generally good among frontline staff, but important gaps exist, which might be improved by targeted education and training and through developing clearer messages about cancer risk factors. PMID:21750554
A study of quantum mechanical probabilities in the classical Hodgkin-Huxley model.
Moradi, N; Scholkmann, F; Salari, V
2015-03-01
The Hodgkin-Huxley (HH) model is a powerful model to explain different aspects of spike generation in excitable cells. However, the HH model was proposed in 1952 when the real structure of the ion channel was unknown. It is now common knowledge that in many ion-channel proteins the flow of ions through the pore is governed by a gate, comprising a so-called "selectivity filter" inside the ion channel, which can be controlled by electrical interactions. The selectivity filter (SF) is believed to be responsible for the selection and fast conduction of particular ions across the membrane of an excitable cell. Other (generally larger) parts of the molecule such as the pore-domain gate control the access of ions to the channel protein. In fact, two types of gates are considered here for ion channels: the "external gate", which is the voltage sensitive gate, and the "internal gate" which is the selectivity filter gate (SFG). Some quantum effects are expected in the SFG due to its small dimensions, which may play an important role in the operation of an ion channel. Here, we examine parameters in a generalized model of HH to see whether any parameter affects the spike generation. Our results indicate that the previously suggested semi-quantum-classical equation proposed by Bernroider and Summhammer (BS) agrees strongly with the HH equation under different conditions and may even provide a better explanation in some cases. We conclude that the BS model can refine the classical HH model substantially.
An Improved Correlation between Impression and Uniaxial Creep
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsueh, Chun-Hway; Miranda, Pedro; Becher, Paul F
2006-01-01
A semiempirical correlation between impression and uniaxial creep has been established by Hyde et al. [Int. J. Mech. Sci. 35, 451 (1993) ] using finite element results for materials exhibiting general power-law creep with the stress exponent n in the range 2 {<=} n {<=} 15. Here, we derive the closed-form solution for a special case of viscoelastic materials, i.e., n = 1, subjected to impression creep and obtain the exact correlation between impression and uniaxial creep. This analytical solution serves as a checkpoint for the finite element results. We then perform finite element analyses for the general case tomore » derive a semiempirical correlation, which agrees well with both analytical viscoelastic results and the existing experimental data. Our improved correlation agrees with the correlation of Hyde et al. for n {>=} 4, and the difference increases with decreasing n for n<4.« less
NASA Astrophysics Data System (ADS)
Rooper, Christopher N.; Zimmermann, Mark; Prescott, Megan M.
2017-08-01
Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska's marine waters, and are associated with many different species of fishes and invertebrates. These ecosystems are vulnerable to the effects of commercial fishing activities and climate change. We compared four commonly used species distribution models (general linear models, generalized additive models, boosted regression trees and random forest models) and an ensemble model to predict the presence or absence and abundance of six groups of benthic invertebrate taxa in the Gulf of Alaska. All four model types performed adequately on training data for predicting presence and absence, with regression forest models having the best overall performance measured by the area under the receiver-operating-curve (AUC). The models also performed well on the test data for presence and absence with average AUCs ranging from 0.66 to 0.82. For the test data, ensemble models performed the best. For abundance data, there was an obvious demarcation in performance between the two regression-based methods (general linear models and generalized additive models), and the tree-based models. The boosted regression tree and random forest models out-performed the other models by a wide margin on both the training and testing data. However, there was a significant drop-off in performance for all models of invertebrate abundance ( 50%) when moving from the training data to the testing data. Ensemble model performance was between the tree-based and regression-based methods. The maps of predictions from the models for both presence and abundance agreed very well across model types, with an increase in variability in predictions for the abundance data. We conclude that where data conforms well to the modeled distribution (such as the presence-absence data and binomial distribution in this study), the four types of models will provide similar results, although the regression-type models may be more consistent with biological theory. For data with highly zero-inflated distributions and non-normal distributions such as the abundance data from this study, the tree-based methods performed better. Ensemble models that averaged predictions across the four model types, performed better than the GLM or GAM models but slightly poorer than the tree-based methods, suggesting ensemble models might be more robust to overfitting than tree methods, while mitigating some of the disadvantages in predictive performance of regression methods.
NASA Technical Reports Server (NTRS)
Shindell, Drew Todd; Racherla, Pavan; Milly, George Peter
2014-01-01
In his comment, Laprise raises several points that we agree merit consideration. His primary critique is that our study [Racherla et al., 2012] tested the ability of the WRF regional climate model to reproduce historical temperature and precipitation change relative to the driving global climate model (GCM) using only a single simulation rather than an ensemble. He asserts that the observed changes are smaller than the internal variability in the climate system (i.e., not statistically significant) and that thus a single simulation should not necessarily be able to capture the observations. Laprise points out that the statistical signal is reduced for a multi-decadal trend such as the one we analyzed in comparison with mean climatology and cites two studies showing that for particular climate parameters it can take any years for a signal to be discerned over internal variability. He states that The results of theexperiment as designed were strongly influenced by the presence of internal variability and sampling errors,which masked the rather small climate changes that may have occurred as a consequence of changes inforcing during the period considered. While Laprise discusses statistics in general terms at some length, for the actual climate trends examined in our study, he offers no evidence that the forced signal was smallcompared with internal variability. The two studies he cites [de Ela et al., 2013; Maraun, 2013] do not provide convincing evidence as they concern climate variables averaged over different times and areas. One in fact examines extreme precipitation events, which by definition are rare and thus have a lower significance level. We accept the general point that it is important to consider internal variability, and as noted in our paper we agree that an ensemble of simulations is in principle an optimal, though computationally expensive, approach. While we did not present the statistical significance of the observations in our original paper, we have now evaluated those for the regional temperature trends used in our study to evaluate the added value of WRF and thus can analyze data as to the magnitude of the trends with respect to internal variability.
Helicity moduli of three-dimensional dilute XY models
NASA Astrophysics Data System (ADS)
Garg, Anupam; Pandit, Rahul; Solla, Sara A.; Ebner, C.
1984-07-01
The helicity moduli of various dilute, classical XY models on three-dimensional lattices are studied with a view to understanding some aspects of the superfluidity of 4He in Vycor glass. A spinwave calculation is used to obtain the low-temperature helicity modulus of a regularly-diluted XY model. A similar calculation is performed for the randomly bond-diluted and site-diluted XY models in the limit of low dilution. A Monte Carlo simulation is used to obtain the helicity modulus of the randomly bond-diluted XY model over a wide range of temperature and dilution. It is found that the randomly diluted models do agree and the regularly diluted model does not agree with certain experimentally found features of the variation in superfluid fraction with coverage of 4He in Vycor glass.
Health-related quality-of-life in low-income, uninsured men with prostate cancer.
Krupski, Tracey L; Fink, Arlene; Kwan, Lorna; Maliski, Sally; Connor, Sarah E; Clerkin, Barbara; Litwin, Mark S
2005-05-01
The objective was to describe health-related quality-of-life (HRQOL) in low-income men with prostate cancer. Subjects were drawn from a statewide public assistance prostate cancer program. Telephone and mail surveys included the RAND 12-item Health Survey and UCLA Prostate Cancer Index Short Form and were compared with normative age-matched men without cancer from the general population reported on in the literature. Of 286 eligible men, 233 (81%) agreed to participate and completed the necessary items. The sample consisted of 51% Hispanics, 23% non-Hispanic whites, and 17% African Americans. The low-income men had worse scores in every domain of prostate-specific and general HRQOL than had the age-matched general population controls. The degree of disparity indicated substantial clinical differences in almost every domain of physical and emotional functioning between the sample group and the control group. Linear regression modeling determined that among the low-income men, Hispanic race, and income level were predictive of worse physical functioning, whereas only comorbidities predicted mental health. Low-income patients with prostate cancer appear to have quality-of-life profiles that are meaningfully worse than age-matched men from the general population without cancer reported on in the literature.
Saturday Morning Science programs: a model to increase diversity in the biosciences.
Phillips, James L; Harris, Toi Blakley; Ihedigbo, Kara M Green; Hawkins, Jacqueline
2012-01-01
To examine a pathway program for middle and high school students from underrepresented backgrounds designed to foster career interest in the biomedical sciences. In 2002, the Institute of Medicine released a report entitled Unequal Treatment, which examined the racial and ethnic disparities in health and health care within the United States and encouraged the development of a diverse health care workforce as a means to reduce health care disparities. Saturday Morning Science (SMS) is a program model presented as a pipeline strategy that addresses this specific recommendation. SMS is a 10-week program that emphasized the importance of science and math. Post-SMS evaluations were conducted to assess biomedical career knowledge, attitudes regarding future career plans, and the effectiveness of the program. A total of 87.5% of middle and high school students who were enrolled in SMS completed the program (113 of 130). Seventy percent of SMS participants were underrepresented minorities. Snapshot program evaluation data exposed new ideas about science (strongly agree/agree, 98%; 64 of 65), exposed new ideas about medicine (strongly agree/agree, 97%; 63 of 65, and increased desire to enter science related field (strongly agree/agree 82% (53 of 65). SMS was designed to motivate students of underrepresented ethnic backgrounds from middle through high school to attend college and prepare for careers in the health sciences. SMS students had the opportunity to interact with scientists, physicians, medical and graduate students, and other academicians. They provided direction and guidance to ensure that students had meaningful experiences specifically designed to expose them to opportunities in the biosciences.
Global observations of thermospheric temperature and nitric oxide from MIPAS spectra at 5.3 μm
NASA Astrophysics Data System (ADS)
Bermejo-Pantaleón, D.; Funke, B.; López-Puertas, M.; GarcíA-Comas, M.; Stiller, G. P.; von Clarmann, T.; Linden, A.; Grabowski, U.; HöPfner, M.; Kiefer, M.; Glatthor, N.; Kellmann, S.; Lu, G.
2011-10-01
We present vertically resolved thermospheric temperatures and NO abundances in terms of volume mixing ratio retrieved simultaneously from spectrally resolved 5.3 μm emissions recorded by the Michelson Interferometer for Passive Atmospheric Spectroscopy (MIPAS) in its upper atmospheric observation mode during 2005-2009. These measurements are unique since they represent the first global observations of temperature and NO for both day and night conditions taken from space. A retrieval scheme has been developed which accounts for vibrational, rotational and spin-orbit non-LTE distributions of NO. Retrieved polar temperature and NO profiles have a vertical resolution of 5-10 km for high Ap values, and degrade to 10-20 km for low Ap conditions. Though retrieved NO abundances depend strongly on the atomic oxygen profile used in the non-LTE modeling, observations can be compared to model results in a consistent manner by applying a simple correction. Apart from this, total retrieval errors are dominated by instrumental noise. The typical single measurement precision of temperature and NO abundances are 5-40 K and 10-30%, respectively, for high Ap values, increasing to 30-70 K for Tk and 20-50% for NO VMR for low Ap conditions. Temperature and NO profiles observed under auroral conditions are rather insensitive to smoothing errors related to the mapping of a priori profile shapes. However, for extra-polar and low Ap conditions, a potential systematic bias in the retrieved nighttime temperature and NO profiles related to smoothing errors has been identified from a comparison to Thermosphere Ionosphere Mesosphere Electrodynamics General Circulation Model (TIME-GCM) simulations. We have constructed a solar minimum monthly climatology of thermospheric temperature and NO from MIPAS observations taken during 2008-2009. MIPAS temperature distributions agree well, on average, with the Mass Spectrometer and Incoherent Scatter radar model (NRLMSISE-00), but some systematic differences exist. MIPAS temperatures are generally colder than NRLMSISE-00 in the polar middle thermosphere (mainly in the summer polar region) by up to 40 K; and are warmer than NRLMSISE-00 in the lower thermosphere around 120-125 km by 10-40 K. Thermospheric NO daytime distributions agree well with the Nitric Oxide Empirical Model (NOEM), based on Student Nitric Oxide Explorer (SNOE) observations. A comparison of MIPAS NO number density with the previous climatology for the declining phases of the solar cycle based on HALOE and SME data shows that MIPAS is generally larger with values ranging from 10 to 40%, except in the auroral region and at the equatorial latitudes above 130 km where the MIPAS/HALOE+SME ratio varies from 1.6 to 2. Day-night differences in MIPAS NO show daytime enhancements of up to 140% in the tropical and midlatitudes middle thermosphere. In the lower thermosphere, the diurnal amplitude is smaller and NO concentrations are generally higher during night by about 10-30%, particularly in the auroral regions.
Fairchild, Pamela Susan; Haefner, Jessica Katherine; Berger, Mitchell Brian
2016-01-01
The aim of the study was to investigate patients' experiences and preferences regarding sexual history taking. We also sought to compare preferences between women in general gynecology versus urogynecology clinics and between women of different ages. This is a survey of 219 patients presenting in gynecology and 164 in urogynecology clinics. Surveys were voluntary and anonymous. Survey instruments included questions about sexual function, past experiences, and preferences regarding taking a clinical sexual history. Subjects agreed that sexual health is important for overall health and should be asked about regularly. Most respondents were not embarrassed to discuss sexual history. When asked about experience with providers, subjects reported that their primary care providers (PCPs) inquired infrequently about their sexual health. Respondents perceived that obstetrician-gynecologists asked about sexual health more frequently than PCPs. There were no significant differences between general gynecology and urogynecology patients' history-taking preferences. Younger women were more likely to feel that sexual health was an important aspect of overall well-being, whereas older women were more likely to agree that sexual problems are unavoidable with age. On logistic regression, there was an association between the ages of younger than 40 years and expressing agreement that providers should frequently ask patients about sexual health. Agreeing that sexual health is an important part of well-being was also associated with being in the 40 years or younger group. Patients place importance on sexual health history as part of their overall health, and providers should more frequently query their patients about this topic. Both PCPs and obstetrician-gynecologists have room for improvement.
ADEA/AAL Institute for Allied Health Educators: Program Evaluation.
Gadbury-Amyot, Cynthia C; Overman, Pamela R; Grzesikowski, Tami; Tucker-Lively, Felicia; Weinstein, George; Haden, N Karl
2015-05-01
Revised accreditation standards for dental and dental hygiene education programs have increased emphasis on faculty development that can improve teaching and learning, foster curricular change including use of teaching and learning technologies, and enhance retention and satisfaction of faculty. The American Dental Education Association (ADEA) and Academy for Academic Leadership (AAL) established the Institute for Allied Health Educators (IAHE) in 2007 to address faculty development needs for allied dental and allied health educators. In 2009, it was transitioned to an online program, which resulted in increased enrollment and diversity of participants. After seven years, a comprehensive program evaluation was warranted. The authors developed an online questionnaire based on Kirkpatrick's four-level model of training evaluation; for this study, levels one (satisfaction), two (knowledge and skill acquisition), and three (behavior change) were examined. Of the 400 program participants invited to take part in the study, a 38% response rate was achieved, with the majority indicating full-time faculty status. Nearly all (95-97%) of the respondents agreed or strongly agreed the program contributed to their teaching effectiveness, and 88-96% agreed or strongly agreed it enhanced their knowledge of educational concepts and strategies. In addition, 83% agreed or strongly agreed the program helped them develop new skills and confidence with technology, with 69% agreeing or strongly agreeing that it helped them incorporate technology into their own educational setting. Nearly 90% were highly positive or positive in their overall assessment of the program; 95% indicated they would recommend it to a colleague; and 80% agreed or strongly agreed they had discussed what they learned with faculty colleagues at their home institutions who had not attended the program. Positive findings from this evaluation provide evidence that the IAHE has been able to meet its goals.
Evolution of the Air Component Commander Post Goldwater-Nichols
2013-06-01
example, before Brigadier General James Mattis led Marine forces in the taking of Kandahar, he spoke with Moseley; and they agreed to conduct the...These separated commands and the division of airpower, along 3 James A. Winnefeld and Dana J...Biography: Lieutenant General Michael C. Short,” July 2000., http://www.af.mil/information/ bios /bio.asp?bioID=7136 (accessed March 20, 2013). 27 Short
Developing Competencies for Navy Human Resource Management Specialists: A Delphi Approach.
1983-06-01
93] (Expert in Consulting Processes) Organizational Diagnosis (Able to identify and res- pond to an organization’s real needs) (Resolve...consensus were those skills and knowledge generally agreed in the profession as necessary for any OD effort to be successful such as organizational ... diagnosis , designing and executing an intervention, process consultation, entry and contracting, general interpersonal skills, and organization behavior
NASA Astrophysics Data System (ADS)
Garcia, E. V.; Stassun, Keivan G.; Pavlovski, K.; Hensberge, H.; Gómez Maqueo Chew, Y.; Claret, A.
2014-09-01
We determine the absolute dimensions of the eclipsing binary V578 Mon, a detached system of two early B-type stars (B0V + B1V, P = 2.40848 days) in the star-forming region NGC 2244 of the Rosette Nebula. From the light curve analysis of 40 yr of photometry and the analysis of HERMES spectra, we find radii of 5.41 ± 0.04 R⊙ and 4.29 ± 0.05 R⊙, and temperatures of 30,000 ± 500 K and 25,750 ± 435 K, respectively. We find that our disentangled component spectra for V578 Mon agree well with previous spectral disentangling from the literature. We also reconfirm the previous spectroscopic orbit of V578 Mon finding that masses of 14.54 ± 0.08 M⊙ and 10.29 ± 0.06 M⊙ are fully compatible with the new analysis. We compare the absolute dimensions to the rotating models of the Geneva and Utrecht groups and the models of the Granada group. We find that all three sets of models marginally reproduce the absolute dimensions of both stars with a common age within the uncertainty for gravity-effective temperature isochrones. However, there are some apparent age discrepancies for the corresponding mass-radius isochrones. Models with larger convective overshoot, >0.35, worked best. Combined with our previously determined apsidal motion of 0.07089^{+0.00021}_{-0.00013} deg cycle-1, we compute the internal structure constants (tidal Love number) for the Newtonian and general relativistic contribution to the apsidal motion as log k 2 = -1.975 ± 0.017 and log k 2 = -3.412 ± 0.018, respectively. We find the relativistic contribution to the apsidal motion to be small, <4%. We find that the prediction of log k 2, theo = -2.005 ± 0.025 of the Granada models fully agrees with our observed log k 2.
Building the database for introduced plants in the United States
Qinfeng Guo; Josephine Falcone; Joe Brownsmith
2009-01-01
More than 4000 nonnative plant species have been introduced to the U.S. and Canada. Identifying potentially invasive species is an important goal. Ecologists have generally agreed that there is no simple biological predictor of invasion...
NASA Astrophysics Data System (ADS)
Shahir Yahya, Mohd; Rahim, Abd Khalil Abd; Mohammad, Musli; Ibrahim, Mustaffa; Kadis, Ghazali
2017-08-01
This paper is about the perceptions of the pilgrims to the innovation of the portable training set for hajj course (P.A.H.A.M). The acronym P.A.H.A.M come from the Malay word “Praktikal Haji Mudahalih” as a tool in helping the hajj and umrah pilgrims to better understand the concept while doing the hajj and umrah practical. In Malaysia, one of the managing bodies of pilgrimage for Muslims in is Pilgrims Fund Board. It provides a series of courses every year to help in boosting the understanding of the pilgrims before leaving for the Holy Land. During the practical session, they will provide the replica model to help pilgrims to familiarise themselves with the actual situation in Mecca. However, the current replica model was built using an iron structure that is relatively heavy, not portable and embarks more cost of transportation and labour. Therefore, this paper discusses the perceptions of the pilgrims on the characteristics of Portable Training Set for Hajj Course (P.A.H.A.M) compared to the existing set in order to increase the understanding of pilgrims. A total of 53 samples of hajj and umrah pilgrims participated in this study consisted of the general public. From the data analysed using Statistical Software for Social Sciences (SPSS v19), the results of the survey showed that more than 90% of respondents agreed that this portable training set meets the characteristics such as easy to handle, more safety in crowd, portable, stability, light weight, suitable in-door and out-door activity, easy to clean, and more structured with average score 4.00 (agreed) and above. In conclusion, it is expected that this Portable Training Set for Hajj Course (P.A.H.A.M) can be used by Muslim’s communities in Malaysia particularly and Muslim countries in general to better understand the hajj and umrah activities before leaving to the Holy Land.
Knowledge and attitude of Saudi mothers towards their preschool children’s oral health
Al-Zahrani, Ali M; Al-Mushayt, Abdullah S; Otaibi, Meshari F; Wyne, Amjad H
2014-01-01
Objectives: To determine knowledge and attitude of Saudi mothers towards their preschool children’s oral health. Methods: One hundred and one mothers (of children aged 16 to 40 months) attending well-baby clinics at Security Forces Hospital Polyclinics in Makkah Al-Mukarrama participated in the study. A questionnaire was used to collect the required information. Results: A great majority (92.1%) of the mothers agreed that “baby teeth are important for child’s general health. Similarly, 90.1% of the mothers agreed that “using fluoridated toothpaste helps to prevent tooth decay”. About four in every ten mothers (43.6%) agreed that a child should be allowed to use a bottle at-will when he/she becomes able to hold it. More than half of the mothers (54.5%) agreed that letting baby sleep with bottle still in the mouth was of no harm to teeth. A significantly (p=0.04) higher percentage of high Socioeconomic status (SES) mothers as compared to middle SES mothers (85.9% versus 55.6%) agreed that “frequent feeding with milk or milk formula is of no harm to baby’s teeth”. A significantly (p=003) higher percentage of the middle SES mothers as compared to high SES mothers (66.7% versus 17.4%) agreed that a child should only visit a dentist in case of a dental pain/problem. Conclusions: The mothers need to be educated in several important areas related to feeding, diet and first dental check-up visit of their children. PMID:25097504
Nayak, Lina; Beaulieu, Christopher F; Rubin, Daniel L; Lipson, Jafi A
2013-12-01
Radiology reports are the major, and often only, means of communication between radiologists and their referring clinicians. The purposes of this study are to identify referring physicians' preferences about radiology reports and to quantify their perceived value of multimedia reports (with embedded images) compared with narrative text reports. We contacted 1800 attending physicians from a range of specialties at large tertiary care medical center via e-mail and a hospital newsletter linking to a 24-question electronic survey between July and November 2012. One hundred sixty physicians responded, yielding a response rate of 8.9%. Survey results were analyzed using Statistical Analysis Software (SAS Institute Inc, Cary, NC). Of the 160 referring physicians respondents, 142 (89%) indicated a general interest in reports with embedded images and completed the remainder of the survey questions. Of 142 respondents, 103 (73%) agreed or strongly agreed that reports with embedded images could improve the quality of interactions with radiologists; 129 respondents (91%) agreed or strongly agreed that having access to significant images enhances understanding of a text-based report; 110 respondents (77%) agreed or strongly agreed that multimedia reports would significantly improve referring physician satisfaction; and 85 respondents (60%) felt strongly or very strongly that multimedia reports would significantly improve patient care and outcomes. Creating accessible, readable, and automatic multimedia reports should be a high priority to enhance the practice and satisfaction of referring physicians, improve patient care, and emphasize the critical role radiology plays in current medical care. Copyright © 2013 AUR. Published by Elsevier Inc. All rights reserved.
Breast self-examination: resistance to change.
Del Giudice, M Elisabeth; Tannenbaum, David; Goodwin, Pamela J
2005-05-01
To investigate whether Canadian family practitioners routinely teach breast self-examination (BSE) after publication of the 2001 Canadian Preventive Health Task Force guideline advising them to exclude teaching BSE from periodic health examinations. Self-administered cross-sectional mailed survey. Canada. A random sample of English-speaking general practitioners and physicians certified by the College of Family Physicians of Canada. Current and past BSE practices and opinions on the value of BSE. Response rate was 47.4%. Most respondents (88%) were aware of the new recommendations, yet only 16% had changed their usual practice of routinely teaching BSE. Most physicians agreed that before the recommendation they almost always taught BSE (74.3%). Only 9.5% agreed that physicians should follow the recommendation and not routinely teach BSE. A few also agreed that they now spend less time discussing BSE (25.7%) and that the recommendation has influenced them to stop teaching (12.4%) and encouraging (12.9%) women to practise BSE. Physicians who had changed their BSE practices were less likely to agree that BSE increases early detection of breast cancer and more likely to agree that BSE increases benign breast biopsies. They were also more likely to agree that screening mammography in women older than 50 decreases mortality from breast cancer. This survey, which assessed routine teaching of BSE, revealed poor adherence by Canadian family physicians to a well publicized evidence-based guideline update. Resistance to change could in part be attributed to a lack of knowledge of the supporting evidence, a lack of confidence in the evidence to date, and personal experiences with patients within their practices.
Resourcing the National Goals for Schooling: An Agreed Framework of Principles for Funding Schools
ERIC Educational Resources Information Center
Ministerial Council on Education, Employment, Training and Youth Affairs (NJ1), 2012
2012-01-01
Funding for school education in Australia should be on the basis of clear and agreed policy principles for achieving effectiveness, efficiency, equity and a socially and culturally cohesive society. On the basis of these principles a national framework for funding schools will be supported by complementary State and Commonwealth models for funding…
Impingement-Current-Erosion Characteristics of Accelerator Grids on Two-Grid Ion Thrusters
NASA Technical Reports Server (NTRS)
Barker, Timothy
1996-01-01
Accelerator grid sputter erosion resulting from charge-exchange-ion impingement is considered to be a primary cause of failure for electrostatic ion thrusters. An experimental method was developed and implemented to measure erosion characteristics of ion-thruster accel-grids for two-grid systems as a function of beam current, accel-grid potential, and facility background pressure. Intricate accelerator grid erosion patterns, that are typically produced in a short time (a few hours), are shown. Accelerator grid volumetric and depth-erosion rates are calculated from these erosion patterns and reported for each of the parameters investigated. A simple theoretical volumetric erosion model yields results that are compared to experimental findings. Results from the model and experiments agree to within 10%, thereby verifying the testing technique. In general, the local distribution of erosion is concentrated in pits between three adjacent holes and trenches that join pits. The shapes of the pits and trenches are shown to be dependent upon operating conditions. Increases in beam current and the accel-grid voltage magnitude lead to deeper pits and trenches. Competing effects cause complex changes in depth-erosion rates as background pressure is increased. Shape factors that describe pits and trenches (i.e. ratio of the average erosion width to the maximum possible width) are also affected in relatively complex ways by changes in beam current, ac tel-grid voltage magnitude, and background pressure. In all cases, however, gross volumetric erosion rates agree with theoretical predictions.
Non-Gaussian bias: insights from discrete density peaks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Desjacques, Vincent; Riotto, Antonio; Gong, Jinn-Ouk, E-mail: Vincent.Desjacques@unige.ch, E-mail: jinn-ouk.gong@apctp.org, E-mail: Antonio.Riotto@unige.ch
2013-09-01
Corrections induced by primordial non-Gaussianity to the linear halo bias can be computed from a peak-background split or the widespread local bias model. However, numerical simulations clearly support the prediction of the former, in which the non-Gaussian amplitude is proportional to the linear halo bias. To understand better the reasons behind the failure of standard Lagrangian local bias, in which the halo overdensity is a function of the local mass overdensity only, we explore the effect of a primordial bispectrum on the 2-point correlation of discrete density peaks. We show that the effective local bias expansion to peak clustering vastlymore » simplifies the calculation. We generalize this approach to excursion set peaks and demonstrate that the resulting non-Gaussian amplitude, which is a weighted sum of quadratic bias factors, precisely agrees with the peak-background split expectation, which is a logarithmic derivative of the halo mass function with respect to the normalisation amplitude. We point out that statistics of thresholded regions can be computed using the same formalism. Our results suggest that halo clustering statistics can be modelled consistently (in the sense that the Gaussian and non-Gaussian bias factors agree with peak-background split expectations) from a Lagrangian bias relation only if the latter is specified as a set of constraints imposed on the linear density field. This is clearly not the case of standard Lagrangian local bias. Therefore, one is led to consider additional variables beyond the local mass overdensity.« less
Experimental evaluation of radiosity for room sound-field prediction.
Hodgson, Murray; Nosal, Eva-Marie
2006-08-01
An acoustical radiosity model was evaluated for how it performs in predicting real room sound fields. This was done by comparing radiosity predictions with experimental results for three existing rooms--a squash court, a classroom, and an office. Radiosity predictions were also compared with those by ray tracing--a "reference" prediction model--for both specular and diffuse surface reflection. Comparisons were made for detailed and discretized echograms, sound-decay curves, sound-propagation curves, and the variations with frequency of four room-acoustical parameters--EDT, RT, D50, and C80. In general, radiosity and diffuse ray tracing gave very similar predictions. Predictions by specular ray tracing were often very different. Radiosity agreed well with experiment in some cases, less well in others. Definitive conclusions regarding the accuracy with which the rooms were modeled, or the accuracy of the radiosity approach, were difficult to draw. The results suggest that radiosity predicts room sound fields with some accuracy, at least as well as diffuse ray tracing and, in general, better than specular ray tracing. The predictions of detailed echograms are less accurate, those of derived room-acoustical parameters more accurate. The results underline the need to develop experimental methods for accurately characterizing the absorptive and reflective characteristics of room surfaces, possible including phase.
Spike-train spectra and network response functions for non-linear integrate-and-fire neurons.
Richardson, Magnus J E
2008-11-01
Reduced models have long been used as a tool for the analysis of the complex activity taking place in neurons and their coupled networks. Recent advances in experimental and theoretical techniques have further demonstrated the usefulness of this approach. Despite the often gross simplification of the underlying biophysical properties, reduced models can still present significant difficulties in their analysis, with the majority of exact and perturbative results available only for the leaky integrate-and-fire model. Here an elementary numerical scheme is demonstrated which can be used to calculate a number of biologically important properties of the general class of non-linear integrate-and-fire models. Exact results for the first-passage-time density and spike-train spectrum are derived, as well as the linear response properties and emergent states of recurrent networks. Given that the exponential integrate-fire model has recently been shown to agree closely with the experimentally measured response of pyramidal cells, the methodology presented here promises to provide a convenient tool to facilitate the analysis of cortical-network dynamics.
A DISCUSSION ON DIFFERENT APPROACHES FOR ASSESSING LIFETIME RISKS OF RADON-INDUCED LUNG CANCER.
Chen, Jing; Murith, Christophe; Palacios, Martha; Wang, Chunhong; Liu, Senlin
2017-11-01
Lifetime risks of radon induced lung cancer were assessed based on epidemiological approaches for Canadian, Swiss and Chinese populations, using the most recent vital statistic data and radon distribution characteristics available for each country. In the risk calculation, the North America residential radon risk model was used for the Canadian population, the European residential radon risk model for the Swiss population, the Chinese residential radon risk model for the Chinese population, and the EPA/BEIR-VI radon risk model for all three populations. The results were compared with the risk calculated from the International Commission on Radiological Protection (ICRP)'s exposure-to-risk conversion coefficients. In view of the fact that the ICRP coefficients were recommended for radiation protection of all populations, it was concluded that, generally speaking, lifetime absolute risks calculated with ICRP-recommended coefficients agree reasonably well with the range of radon induced lung cancer risk predicted by risk models derived from epidemiological pooling analyses. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Erath, Byron D; Zañartu, Matías; Peterson, Sean D
2017-06-01
The mechanics of vocal fold contact during phonation is known to play a crucial role in both normal and pathological speech production, though the underlying physics is not well understood. Herein, a viscoelastic model of the stresses during vocal fold contact is developed. This model assumes the cover to be a poroelastic structure wherein interstitial fluid translocates in response to mechanical squeezing. The maximum interstitial fluid pressure is found to generally increase with decreasing viscous dissipation and/or decreasing tissue elasticity. A global minimum in the total contact stress, comprising interstitial fluid pressure and elastic stress in the tissue, is observed over the studied dimensionless parameter range. Interestingly, physiologically reasonable estimates for the governing parameters fall within this global minimum region. The model is validated against prior experimental and computational work, wherein the predicted contact stress magnitude and impact duration agree well with published results. Lastly, observations of the potential relationship between vocal fold hydration and increased risk of tissue damage are discussed based upon model predictions of stress as functions of cover layer thickness and viscosity.
The effect of interface properties on nickel base alloy composites
NASA Technical Reports Server (NTRS)
Groves, M.; Grossman, T.; Senemeier, M.; Wright, K.
1995-01-01
This program was performed to assess the extent to which mechanical behavior models can predict the properties of sapphire fiber/nickel aluminide matrix composites and help guide their development by defining improved combinations of matrix and interface coating. The program consisted of four tasks: 1) selection of the matrices and interface coating constituents using a modeling-based approach; 2) fabrication of the selected materials; 3) testing and evaluation of the materials; and 4) evaluation of the behavior models to develop recommendations. Ni-50Al and Ni-20AI-30Fe (a/o) matrices were selected which gave brittle and ductile behavior, respectively, and an interface coating of PVD YSZ was selected which provided strong bonding to the sapphire fiber. Significant fiber damage and strength loss was observed in the composites which made straightforward comparison of properties with models difficult. Nevertheless, the models selected generally provided property predictions which agreed well with results when fiber degradation was incorporated. The presence of a strong interface bond was felt to be detrimental in the NiAI MMC system where low toughness and low strength were observed.
NASA Astrophysics Data System (ADS)
Cai, Tao; Guo, Songtao; Li, Yongzeng; Peng, Di; Zhao, Xiaofeng; Liu, Yingzheng
2018-04-01
The mechanoluminescent (ML) sensor is a newly developed non-invasive technique for stress/strain measurement. However, its application has been mostly restricted to qualitative measurement due to the lack of a well-defined relationship between ML intensity and stress. To achieve accurate stress measurement, an intensity ratio model was proposed in this study to establish a quantitative relationship between the stress condition and its ML intensity in elastic deformation. To verify the proposed model, experiments were carried out on a ML measurement system using resin samples mixed with the sensor material SrAl2O4:Eu2+, Dy3+. The ML intensity ratio was found to be dependent on the applied stress and strain rate, and the relationship acquired from the experimental results agreed well with the proposed model. The current study provided a physical explanation for the relationship between ML intensity and its stress condition. The proposed model was applicable in various SrAl2O4:Eu2+, Dy3+-based ML measurement in elastic deformation, and could provide a useful reference for quantitative stress measurement using the ML sensor in general.
Synchronicity in predictive modelling: a new view of data assimilation
NASA Astrophysics Data System (ADS)
Duane, G. S.; Tribbia, J. J.; Weiss, J. B.
2006-11-01
The problem of data assimilation can be viewed as one of synchronizing two dynamical systems, one representing "truth" and the other representing "model", with a unidirectional flow of information between the two. Synchronization of truth and model defines a general view of data assimilation, as machine perception, that is reminiscent of the Jung-Pauli notion of synchronicity between matter and mind. The dynamical systems paradigm of the synchronization of a pair of loosely coupled chaotic systems is expected to be useful because quasi-2D geophysical fluid models have been shown to synchronize when only medium-scale modes are coupled. The synchronization approach is equivalent to standard approaches based on least-squares optimization, including Kalman filtering, except in highly non-linear regions of state space where observational noise links regimes with qualitatively different dynamics. The synchronization approach is used to calculate covariance inflation factors from parameters describing the bimodality of a one-dimensional system. The factors agree in overall magnitude with those used in operational practice on an ad hoc basis. The calculation is robust against the introduction of stochastic model error arising from unresolved scales.
Using Transport Diagnostics to Understand Chemistry Climate Model Ozone Simulations
NASA Technical Reports Server (NTRS)
Strahan, S. E.; Douglass, A. R.; Stolarski, R. S.; Akiyoshi, H.; Bekki, S.; Braesicke, P.; Butchart, N.; Chipperfield, M. P.; Cugnet, D.; Dhomse, S.;
2010-01-01
We demonstrate how observations of N2O and mean age in the tropical and midlatitude lower stratosphere (LS) can be used to identify realistic transport in models. The results are applied to 15 Chemistry Climate Models (CCMs) participating in the 2010 WMO assessment. Comparison of the observed and simulated N2O/mean age relationship identifies models with fast or slow circulations and reveals details of model ascent and tropical isolation. The use of this process-oriented N2O/mean age diagnostic identifies models with compensating transport deficiencies that produce fortuitous agreement with mean age. We compare the diagnosed model transport behavior with a model's ability to produce realistic LS O3 profiles in the tropics and midlatitudes. Models with the greatest tropical transport problems show the poorest agreement with observations. Models with the most realistic LS transport agree more closely with LS observations and each other. We incorporate the results of the chemistry evaluations in the SPARC CCMVal Report (2010) to explain the range of CCM predictions for the return-to-1980 dates for global (60 S-60 N) and Antarctic column ozone. Later (earlier) Antarctic return dates are generally correlated to higher (lower) vortex Cl(sub y) levels in the LS, and vortex Cl(sub y) is generally correlated with the model's circulation although model Cl(sub y) chemistry or Cl(sub y) conservation can have a significant effect. In both regions, models that have good LS transport produce a smaller range of predictions for the return-to-1980 ozone values. This study suggests that the current range of predicted return dates is unnecessarily large due to identifiable model transport deficiencies.
Hypernatural Monitoring: A Social Rehearsal Account of Smartphone Addiction
Veissière, Samuel P. L.; Stendel, Moriah
2018-01-01
We present a deflationary account of smartphone addiction by situating this purportedly antisocial phenomenon within the fundamentally social dispositions of our species. While we agree with contemporary critics that the hyper-connectedness and unpredictable rewards of mobile technology can modulate negative affect, we propose to place the locus of addiction on an evolutionarily older mechanism: the human need to monitor and be monitored by others. Drawing from key findings in evolutionary anthropology and the cognitive science of religion, we articulate a hypernatural monitoring model of smartphone addiction grounded in a general social rehearsal theory of human cognition. Building on recent predictive-processing views of perception and addiction in cognitive neuroscience, we describe the role of social reward anticipation and prediction errors in mediating dysfunctional smartphone use. We conclude with insights from contemplative philosophies and harm-reduction models on finding the right rituals for honoring social connections and setting intentional protocols for the consumption of social information. PMID:29515480
Hypernatural Monitoring: A Social Rehearsal Account of Smartphone Addiction.
Veissière, Samuel P L; Stendel, Moriah
2018-01-01
We present a deflationary account of smartphone addiction by situating this purportedly antisocial phenomenon within the fundamentally social dispositions of our species. While we agree with contemporary critics that the hyper-connectedness and unpredictable rewards of mobile technology can modulate negative affect, we propose to place the locus of addiction on an evolutionarily older mechanism: the human need to monitor and be monitored by others. Drawing from key findings in evolutionary anthropology and the cognitive science of religion, we articulate a hypernatural monitoring model of smartphone addiction grounded in a general social rehearsal theory of human cognition. Building on recent predictive-processing views of perception and addiction in cognitive neuroscience, we describe the role of social reward anticipation and prediction errors in mediating dysfunctional smartphone use. We conclude with insights from contemplative philosophies and harm-reduction models on finding the right rituals for honoring social connections and setting intentional protocols for the consumption of social information.
Estimating effective data density in a satellite retrieval or an objective analysis
NASA Technical Reports Server (NTRS)
Purser, R. J.; Huang, H.-L.
1993-01-01
An attempt is made to formulate consistent objective definitions of the concept of 'effective data density' applicable both in the context of satellite soundings and more generally in objective data analysis. The definitions based upon various forms of Backus-Gilbert 'spread' functions are found to be seriously misleading in satellite soundings where the model resolution function (expressing the sensitivity of retrieval or analysis to changes in the background error) features sidelobes. Instead, estimates derived by smoothing the trace components of the model resolution function are proposed. The new estimates are found to be more reliable and informative in simulated satellite retrieval problems and, for the special case of uniformly spaced perfect observations, agree exactly with their actual density. The new estimates integrate to the 'degrees of freedom for signal', a diagnostic that is invariant to changes of units or coordinates used.
Ab initio description of p-shell hypernuclei.
Wirth, Roland; Gazda, Daniel; Navrátil, Petr; Calci, Angelo; Langhammer, Joachim; Roth, Robert
2014-11-07
We present the first ab initio calculations for p-shell single-Λ hypernuclei. For the solution of the many-baryon problem, we develop two variants of the no-core shell model with explicit Λ and Σ(+),Σ(0),Σ(-) hyperons including Λ-Σ conversion, optionally supplemented by a similarity renormalization group transformation to accelerate model-space convergence. In addition to state-of-the-art chiral two- and three-nucleon interactions, we use leading-order chiral hyperon-nucleon interactions and a recent meson-exchange hyperon-nucleon interaction. We validate the approach for s-shell hypernuclei and apply it to p-shell hypernuclei, in particular to (Λ)(7)Li, (Λ)(9)Be, and (Λ)(13)C. We show that the chiral hyperon-nucleon interactions provide ground-state and excitation energies that generally agree with experiment within the cutoff dependence. At the same time we demonstrate that hypernuclear spectroscopy provides tight constraints on the hyperon-nucleon interactions.
Towards an alternative evolution model.
van Waesberghe, H
1982-01-01
Lamarck and Darwin agreed on the inconstancy of species and on the exclusive gradualism of evolution (nature does not jump). Darwinism, revived as neo-Darwinism, was almost generally accepted from about 1930 till 1960. In the sixties the evolutionary importance of selection has been called in question by the neutralists. The traditional conception of the gene is disarranged by recent molecular-biological findings. Owing to the increasing confusion about the concept of genotype, this concept is reconsidered. The idea of the genotype as a cluster of genes is replaced by a cybernetical interpretation of the genotype. As nature does jump, exclusive gradualism is dismissed. Saltatory evolution is a natural phenomenon, provided by a sudden collapse of the thresholds which resist against evolution. The fossil record and the taxonomic system call for a macromutational interpretation. As Lamarck and Darwin overlooked the resistance of evolutionary thresholds, an alternative evolution model is needed, the first to be constructed on a palaeontological and taxonomic basis.
Dynamics of social contagions with local trend imitation.
Zhu, Xuzhen; Wang, Wei; Cai, Shimin; Stanley, H Eugene
2018-05-09
Research on social contagion dynamics has not yet included a theoretical analysis of the ubiquitous local trend imitation (LTI) characteristic. We propose a social contagion model with a tent-like adoption probability to investigate the effect of this LTI characteristic on behavior spreading. We also propose a generalized edge-based compartmental theory to describe the proposed model. Through extensive numerical simulations and theoretical analyses, we find a crossover in the phase transition: when the LTI capacity is strong, the growth of the final adoption size exhibits a second-order phase transition. When the LTI capacity is weak, we see a first-order phase transition. For a given behavioral information transmission probability, there is an optimal LTI capacity that maximizes the final adoption size. Finally we find that the above phenomena are not qualitatively affected by the heterogeneous degree distribution. Our suggested theoretical predictions agree with the simulation results.
On the photometric homogeneity of Type IA supernovae
NASA Astrophysics Data System (ADS)
Bravo, E.; Dominguez, I.; Isern, J.; Canal, R.; Hoeflich, P.; Labay, J.
1993-03-01
The dependence of the characteristics of the light curves of Type Ia supernovae on the ignition density of the progenitor white dwarf is studied with the aid of two models of propagation of the thermonuclear burning front: as a deflagration and as a delayed detonation. The light curve is computed from opacities which take into account the velocity gradients. The results show that in all cases the resulting light curves roughly agree with observations and that they are not sensitive to the ignition density of the white dwarf. Only the model corresponding to a deflagration starting at a density of 8 x 10 exp 9 g/cu cm shows a deviation from the general behavior, having a significantly lower luminosity at maximum. A dispersion of about 1000 km/s is found in the computed expansion velocities at maximum, which compares well with that found in the observations.
Theoretical analysis of ozone generation by pulsed dielectric barrier discharge in oxygen
NASA Astrophysics Data System (ADS)
Wei, L. S.; Zhou, J. H.; Wang, Z. H.; Cen, K. F.
2007-08-01
The use of very short high-voltage pulses combined with a dielectric layer results in high-energy electrons that dissociate oxygen molecules into atoms, which are a prerequisite for the subsequent production of ozone by collisions with oxygen molecules and third particles. The production of ozone depends on both the electrical and the physical parameters. For ozone generation by pulsed dielectric barrier discharge in oxygen, a mathematical model, which describes the relation between ozone concentration and these parameters that are of importance in its design, is developed according to dimensional analysis theory. A formula considering the ozone destruction factor is derived for predicting the characteristics of the ozone generation, within the range of the corona inception voltage to the gap breakdown voltage. The trend showing the dependence of the concentration of ozone in oxygen on these parameters generally agrees with the experimental results, thus confirming the validity of the mathematical model.
NASA Technical Reports Server (NTRS)
Moul, T. M.
1979-01-01
A preliminary wind tunnel investigation was undertaken to determine the flow correction for a vane angle of attack sensor over an angle of attack range from -10 deg to 110 deg. The sensor was mounted ahead of the wing on a 1/5 scale model of a general aviation airplane. It was shown that the flow correction was substantial, reaching about 15 deg at an angle of attack of 90 deg. The flow correction was found to increase as the sensor was moved closer to the wing or closer to the fuselage. The experimentally determined slope of the flow correction versus the measured angle of attack below the stall angle of attack agreed closely with the slope of flight data from a similar full scale airplane.
Executable Architecture Research at Old Dominion University
NASA Technical Reports Server (NTRS)
Tolk, Andreas; Shuman, Edwin A.; Garcia, Johnny J.
2011-01-01
Executable Architectures allow the evaluation of system architectures not only regarding their static, but also their dynamic behavior. However, the systems engineering community do not agree on a common formal specification of executable architectures. To close this gap and identify necessary elements of an executable architecture, a modeling language, and a modeling formalism is topic of ongoing PhD research. In addition, systems are generally defined and applied in an operational context to provide capabilities and enable missions. To maximize the benefits of executable architectures, a second PhD effort introduces the idea of creating an executable context in addition to the executable architecture. The results move the validation of architectures from the current information domain into the knowledge domain and improve the reliability of such validation efforts. The paper presents research and results of both doctoral research efforts and puts them into a common context of state-of-the-art of systems engineering methods supporting more agility.
Surface-peaked medium effects in the interaction of nucleons with finite nuclei
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguayo, F. J.; Arellano, H. F.
We investigate the asymptotic separation of the optical model potential for nucleon-nucleus scattering in momentum space, where the potential is split into a medium-independent term and another depending exclusively on the gradient of the density-dependent g matrix. This decomposition confines the medium sensitivity of the nucleon-nucleus coupling to the surface of the nucleus. We examine this feature in the context of proton-nucleus scattering at beam energies between 30 and 100 MeV and find that the pn coupling accounts for most of this sensitivity. Additionally, based on this general structure of the optical potential we are able to treat both, themore » medium dependence of the effective interaction and the full mixed density as described by single-particle shell models. The calculated scattering observables agree within 10% with those obtained by Arellano, Brieva, and Love in their momentum-space g-folding approach.« less
Schroeder, Susan A.; Fulton, David C.
2017-01-01
Although researchers agree that public participation in natural resource decision making is critical to institutional acceptance by stakeholders and the general public, the processes to gain public perceptions of fairness, agency trust, and acceptance of management decisions are not clear. Using results from a mail survey of Minnesota resident anglers, we used structural equation modeling to examine how instrumental versus symbolic motives related to anglers’ perceptions of agency fairness, trustworthiness, and ultimately acceptance of fisheries management decisions. We applied laboratory research on relationships among procedural fairness, trust, and management acceptance, and then tested models incorporating anglers’ perceptions of voice for anglers and nonanglers in management decisions. Results suggested that trust fully mediated the relationship between procedural fairness and management acceptance. Angler perceptions of angler and nonangler voice both related to views of procedural fairness, but angler voice was more strongly related and was also significantly related to acceptance of management decisions.
Wave kinetics of random fibre lasers
Churkin, D V.; Kolokolov, I V.; Podivilov, E V.; Vatnik, I D.; Nikulin, M A.; Vergeles, S S.; Terekhov, I S.; Lebedev, V V.; Falkovich, G.; Babin, S A.; Turitsyn, S K.
2015-01-01
Traditional wave kinetics describes the slow evolution of systems with many degrees of freedom to equilibrium via numerous weak non-linear interactions and fails for very important class of dissipative (active) optical systems with cyclic gain and losses, such as lasers with non-linear intracavity dynamics. Here we introduce a conceptually new class of cyclic wave systems, characterized by non-uniform double-scale dynamics with strong periodic changes of the energy spectrum and slow evolution from cycle to cycle to a statistically steady state. Taking a practically important example—random fibre laser—we show that a model describing such a system is close to integrable non-linear Schrödinger equation and needs a new formalism of wave kinetics, developed here. We derive a non-linear kinetic theory of the laser spectrum, generalizing the seminal linear model of Schawlow and Townes. Experimental results agree with our theory. The work has implications for describing kinetics of cyclical systems beyond photonics. PMID:25645177
Efficient and accurate approach to modeling the microstructure and defect properties of LaCoO3
NASA Astrophysics Data System (ADS)
Buckeridge, J.; Taylor, F. H.; Catlow, C. R. A.
2016-04-01
Complex perovskite oxides are promising materials for cathode layers in solid oxide fuel cells. Such materials have intricate electronic, magnetic, and crystalline structures that prove challenging to model accurately. We analyze a wide range of standard density functional theory approaches to modeling a highly promising system, the perovskite LaCoO3, focusing on optimizing the Hubbard U parameter to treat the self-interaction of the B-site cation's d states, in order to determine the most appropriate method to study defect formation and the effect of spin on local structure. By calculating structural and electronic properties for different magnetic states we determine that U =4 eV for Co in LaCoO3 agrees best with available experiments. We demonstrate that the generalized gradient approximation (PBEsol +U ) is most appropriate for studying structure versus spin state, while the local density approximation (LDA +U ) is most appropriate for determining accurate energetics for defect properties.
Non-Boltzmann Modeling for Air Shock-Layer Radiation at Lunar-Return Conditions
NASA Technical Reports Server (NTRS)
Johnston, Christopher O.; Hollis, Brian R.; Sutton, Kenneth
2008-01-01
This paper investigates the non-Boltzmann modeling of the radiating atomic and molecular electronic states present in lunar-return shock-layers. The Master Equation is derived for a general atom or molecule while accounting for a variety of excitation and de-excitation mechanisms. A new set of electronic-impact excitation rates is compiled for N, O, and N2+, which are the main radiating species for most lunar-return shock-layers. Based on these new rates, a novel approach of curve-fitting the non-Boltzmann populations of the radiating atomic and molecular states is developed. This new approach provides a simple and accurate method for calculating the atomic and molecular non-Boltzmann populations while avoiding the matrix inversion procedure required for the detailed solution of the Master Equation. The radiative flux values predicted by the present detailed non-Boltzmann model and the approximate curve-fitting approach are shown to agree within 5% for the Fire 1634 s case.
NASA Technical Reports Server (NTRS)
Massman, William J.
1987-01-01
The semianalytical model outlined in a previous study (Massman, 1987) to describe momentum exchange between the atmosphere and vegetated surfaces is extended to include the exchange of heat. The methods employed are based on one-dimensional turbulent diffusivities, and use analytical solutions to the steady-state diffusion equation. The model is used to assess the influence that the canopy foliage structure and density, the wind profile structure within the canopy, and the shelter factor can have upon the inverse surface Stanton number (kB exp -1), as well as to explore the consequences of introducing a scalar displacement height which can be different from the momentum displacement height. In general, the triangular foliage area density function gives results which agree more closely with observations than that for constant foliage area density. The intended application of this work is for parameterizing the bulk aerodynamic resistances for heat and momentum exchange for use within large-scale models of plant-atmosphere exchanges.
Rejoinder: Sifting through model space
Heisey, Dennis M.; Osnas, Erik E.; Cross, Paul C.; Joly, Damien O.; Langenberg, Julia A.; Miller, Michael W.
2010-01-01
Observational data sets generated by complex processes are common in ecology. Traditionally these have been very challenging to analyze because of the limitations of available statistical tools. This seems to be changing, and these are exciting times to be involved with ecological statistics, not just because of the neo-Bayesian revival but also because of the proliferation of computationally intensive methods in general. It is now possible to fit much richer models to observational data than in the relatively recent past, which in turn has stimulated much interest in how to evaluate and compare such models. In such an immature, vibrant, and rapidly growing field, not everyone is going to agree on the best way to do things. This is reflected in the contrast of opinions offered by the discussants. Each offers a thoughtful and thought-provoking critique of our work that reflects the current thinking in a non-negligible segment of the ecological data analysis community. We want to thank them for their insights.
NASA Astrophysics Data System (ADS)
Herdeiro, Victor
2017-09-01
Herdeiro and Doyon [Phys. Rev. E 94, 043322 (2016), 10.1103/PhysRevE.94.043322] introduced a numerical recipe, dubbed uv sampler, offering precise estimations of the conformal field theory (CFT) data of the planar two-dimensional (2D) critical Ising model. It made use of scale invariance emerging at the critical point in order to sample finite sublattice marginals of the infinite plane Gibbs measure of the model by producing holographic boundary distributions. The main ingredient of the Markov chain Monte Carlo sampler is the invariance under dilation. This paper presents a generalization to higher dimensions with the critical 3D Ising model. This leads to numerical estimations of a subset of the CFT data—scaling weights and structure constants—through fitting of measured correlation functions. The results are shown to agree with the recent most precise estimations from numerical bootstrap methods [Kos, Poland, Simmons-Duffin, and Vichi, J. High Energy Phys. 08 (2016) 036, 10.1007/JHEP08(2016)036].
Piepers, Daniel W.; Robbins, Rachel A.
2012-01-01
It is widely agreed that the human face is processed differently from other objects. However there is a lack of consensus on what is meant by a wide array of terms used to describe this “special” face processing (e.g., holistic and configural) and the perceptually relevant information within a face (e.g., relational properties and configuration). This paper will review existing models of holistic/configural processing, discuss how they differ from one another conceptually, and review the wide variety of measures used to tap into these concepts. In general we favor a model where holistic processing of a face includes some or all of the interrelations between features and has separate coding for features. However, some aspects of the model remain unclear. We propose the use of moving faces as a way of clarifying what types of information are included in the holistic representation of a face. PMID:23413184
Carbon isotope composition of ambient CO2 and recycling: a matrix simulation model
da Silveira Lobo Sternberg, Leonel; DeAngelis, Donald L.
2002-01-01
The relationship between isotopic composition and concentration of ambient CO2 in a canopy and its associated convective boundary layer was modeled. The model divides the canopy and convective boundary layer into several layers. Photosynthesis, respiration, and exchange between each layer can be simulated by matrix equations. This simulation can be used to calculate recycling; defined here as the amount of respired CO2 re-fixed by photosynthesis relative to the total amount of respired CO2. At steady state the matrix equations can be solved for the canopy and convective boundary layer CO2 concentration and isotopic profile, which can be used to calculate a theoretical recycling index according to a previously developed equation. There is complete agreement between simulated and theoretical recycling indices for different exchange scenarios. Recycling indices from a simulation of gas exchange between a heterogeneous vegetation canopy and the troposphere also agreed with a more generalized form of the theoretical recycling equation developed here.
Extension of nanoconfined DNA: Quantitative comparison between experiment and theory
NASA Astrophysics Data System (ADS)
Iarko, V.; Werner, E.; Nyberg, L. K.; Müller, V.; Fritzsche, J.; Ambjörnsson, T.; Beech, J. P.; Tegenfeldt, J. O.; Mehlig, K.; Westerlund, F.; Mehlig, B.
2015-12-01
The extension of DNA confined to nanochannels has been studied intensively and in detail. However, quantitative comparisons between experiments and model calculations are difficult because most theoretical predictions involve undetermined prefactors, and because the model parameters (contour length, Kuhn length, effective width) are difficult to compute reliably, leading to substantial uncertainties. Here we use a recent asymptotically exact theory for the DNA extension in the "extended de Gennes regime" that allows us to compare experimental results with theory. For this purpose, we performed experiments measuring the mean DNA extension and its standard deviation while varying the channel geometry, dye intercalation ratio, and ionic strength of the buffer. The experimental results agree very well with theory at high ionic strengths, indicating that the model parameters are reliable. At low ionic strengths, the agreement is less good. We discuss possible reasons. In principle, our approach allows us to measure the Kuhn length and the effective width of a single DNA molecule and more generally of semiflexible polymers in solution.
Pust, Nathan J; Dahlberg, Andrew R; Thomas, Michael J; Shaw, Joseph A
2011-09-12
Visible-band and near infrared polarization and radiance images measured with a ground-based full-sky polarimeter are compared against a successive orders of scattering (SOS) radiative transfer model for 2009 summer cloud-free days in Bozeman, Montana, USA. The polarimeter measures radiance and polarization in 10-nm bands centered at 450 nm, 490 nm, 530 nm, 630 nm, and 700 nm. AERONET products are used to represent aerosols in the SOS model, while MISR satellite BRF products are used for the surface reflectance. While model results generally agree well with observation, the simulated degree of polarization is typically higher than observed data. Potential sources of this difference may include cloud contamination and/or underestimation of the AERONET-retrieved aerosol real refractive index. Problems with the retrieved parameters are not unexpected given the low aerosol optical depth range (0.025 to 0.17 at 500 nm) during the study and the corresponding difficulties that these conditions pose to the AERONET inversion algorithm.
Evaluation of Arctic Sea Ice Thickness Simulated by AOMIP Models
NASA Technical Reports Server (NTRS)
Johnson, Mark; Proshutinsky, Andrey; Aksenov, Yevgeny; Nguyen, An T.; Lindsay, Ron; Haas, Christian; Zhang, Jinlun; Diansky, Nimolay; Kwok, Ron; Maslowski, Wieslaw;
2011-01-01
We compare results from six AOMIP model simulations with estimates of sea ice thickness obtained from ICESat, moored and submarine-based upward looking sensors, airborne electromagnetic measurements and drill holes. Our goal is to find patterns of model performance to guide model improvement. The satellite data is pan-arctic from 2004-2008, ice-draft data is from moored instruments in Fram Strait, the Greenland Sea and the Beaufort Sea from 1992-2008 and from submarines from 1975-2000. The drill hole data are from the Laptev and East Siberian marginal seas from 1982-1986 and from coastal stations from 1998-2009. While there are important caveats when comparing modeled results with measurements from different platforms and time periods such as these, the models agree well with moored ULS data. In general, the AOMIP models underestimate the thickness of measured ice thicker than about 2 m and overestimate thickness of ice thinner than 2 m. The simulated results are poor over the fast ice and marginal seas of the Siberian shelves. Averaging over all observational data sets, the better correlations and smaller differences from observed thickness are from the ECCO2 and UW models.
Yang, Xuguang; Shi, Baochang; Chai, Zhenhua
2014-07-01
In this paper, two modified lattice Boltzmann Bhatnagar-Gross-Krook (LBGK) models for incompressible Navier-Stokes equations and convection-diffusion equations are proposed via the addition of correction terms in the evolution equations. Utilizing this modification, the value of the dimensionless relaxation time in the LBGK model can be kept in a proper range, and thus the stability of the LBGK model can be improved. Although some gradient operators are included in the correction terms, they can be computed efficiently using local computational schemes such that the present LBGK models still retain the intrinsic parallelism characteristic of the lattice Boltzmann method. Numerical studies of the steady Poiseuille flow and unsteady Womersley flow show that the modified LBGK model has a second-order convergence rate in space, and the compressibility effect in the common LBGK model can be eliminated. In addition, to test the stability of the present models, we also performed some simulations of the natural convection in a square cavity, and we found that the results agree well with those reported in the previous work, even at a very high Rayleigh number (Ra = 10(12)).
Evidence-based practice guidelines in OHS: are they agree-able?
Hulshof, Carel; Hoenen, John
2007-01-01
The purpose of this study was to evaluate the acceptance, validity, reliability and feasibility of the AGREE (Appraisal of Guidelines and REsearch and Evaluation) instrument to assess the quality of evidence-based practice guidelines for occupational physicians. In total, 6 practice guidelines of the Netherlands Society of Occupational Medicine (NVAB) were appraised by 20 occupational health professionals and experts in guideline development or implementation. Although appraisers often disagreed on individual item scores, the internal consistency and interrater reliability for most domains was sufficient. The AGREE criteria were in general considered relevant and no major suggestions for additional items for use in the context of occupational health were brought up. The domain scores for the individual guidelines show a wide variety: 'applicability' had on average the lowest mean score (53%) while 'scope and purpose' had the highest one (87%). Low scores indicate where improvements are possible and necessary, e.g. by providing more information about the development. Key experts in occupational health report that AGREE is a relevant and easy to use instrument to evaluate quality aspects and the included criteria provide a good framework to develop or update evidence-based practice guidelines in the field of occupational health.
Hoffmann-Eßer, Wiebke; Siering, Ulrich; Neugebauer, Edmund A M; Brockhaus, Anne Catharina; Lampert, Ulrike; Eikermann, Michaela
2017-01-01
The Appraisal of Guidelines for Research & Evaluation (AGREE) II instrument is the most commonly used guideline appraisal tool. It includes 23 appraisal criteria (items) organized within 6 domains and 2 overall assessments (1. overall guideline quality; 2. recommendation for use). The aim of this systematic review was twofold. Firstly, to investigate how often AGREE II users conduct the 2 overall assessments. Secondly, to investigate the influence of the 6 domain scores on each of the 2 overall assessments. A systematic bibliographic search was conducted for publications reporting guideline appraisals with AGREE II. The impact of the 6 domain scores on the overall assessment of guideline quality was examined using a multiple linear regression model. Their impact on the recommendation for use (possible answers: "yes", "yes, with modifications", "no") was examined using a multinomial regression model. 118 relevant publications including 1453 guidelines were identified. 77.1% of the publications reported results for at least one overall assessment, but only 32.2% reported results for both overall assessments. The results of the regression analyses showed a statistically significant influence of all domains on overall guideline quality, with Domain 3 (rigour of development) having the strongest influence. For the recommendation for use, the results showed a significant influence of Domains 3 to 5 ("yes" vs. "no") and Domains 3 and 5 ("yes, with modifications" vs. "no"). The 2 overall assessments of AGREE II are underreported by guideline assessors. Domains 3 and 5 have the strongest influence on the results of the 2 overall assessments, while the other domains have a varying influence. Within a normative approach, our findings could be used as guidance for weighting individual domains in AGREE II to make the overall assessments more objective. Alternatively, a stronger content analysis of the individual domains could clarify their importance in terms of guideline quality. Moreover, AGREE II should require users to transparently present how they conducted the assessments.
JEA's Code of Ethics for Advisers; and Sites for Additional Ethics Information.
ERIC Educational Resources Information Center
Bowen, John
1997-01-01
Lists general principles that media advisers should follow, the 12 points agreed upon as the Journalism Education Association's (JEA) Code of Ethics for Advisers, and a list of Web sites that deal with journalism ethics. (PA)
How psychiatric patients perceive the public's stereotype of mental illness.
Freidl, M; Lang, T; Scherer, M
2003-05-01
It is well established that the general public has devaluating attitudes towards psychiatric patients. In order to avoid rejection, many of these patients develop coping strategies, such as withdrawal and concealing their treatment history. These efforts are in themselves stressing, which might have negative consequences for the course of the disorder. It is not clear, however, how many and which patients do actually perceive the public's stereotype as threatening and, therefore, expect rejection. Ninety psychiatric patients and a sample of 1042 persons of the Austrian general population were asked whether they agreed with five devaluating statements about mental patients contained in a questionnaire developed by Link et al. Matched pairs comparisons and multiple logistic regression were employed in order to find out whether patients agreed with these statements to the same extent as the general population did. For the statements that most people believe that psychiatric patients are "less intelligent", "less trustworthy" and "taken less seriously", patients thought significantly less often than the general population that most people devalue mental patients. For two statements ("personal failure", "think less of") no difference was found. It seems that some psychiatric patients are less convinced than the general population that most people devalue psychiatric patients in specific respects; these patients might fear rejection less than other patients do. Those who actually fear rejection might need antistigma assistance more urgently than the first group.
Tensor renormalization group methods for spin and gauge models
NASA Astrophysics Data System (ADS)
Zou, Haiyuan
The analysis of the error of perturbative series by comparing it to the exact solution is an important tool to understand the non-perturbative physics of statistical models. For some toy models, a new method can be used to calculate higher order weak coupling expansion and modified perturbation theory can be constructed. However, it is nontrivial to generalize the new method to understand the critical behavior of high dimensional spin and gauge models. Actually, it is a big challenge in both high energy physics and condensed matter physics to develop accurate and efficient numerical algorithms to solve these problems. In this thesis, one systematic way named tensor renormalization group method is discussed. The applications of the method to several spin and gauge models on a lattice are investigated. theoretically, the new method allows one to write an exact representation of the partition function of models with local interactions. E.g. O(N) models, Z2 gauge models and U(1) gauge models. Practically, by using controllable approximations, results in both finite volume and the thermodynamic limit can be obtained. Another advantage of the new method is that it is insensitive to sign problems for models with complex coupling and chemical potential. Through the new approach, the Fisher's zeros of the 2D O(2) model in the complex coupling plane can be calculated and the finite size scaling of the results agrees well with the Kosterlitz-Thouless assumption. Applying the method to the O(2) model with a chemical potential, new phase diagram of the models can be obtained. The structure of the tensor language may provide a new tool to understand phase transition properties in general.
Restructuring of the jurisprudence course taught at the Canadian Memorial Chiropractic College
Gleberzon, Brian J.
2010-01-01
Introduction: The process by which the jurisprudence course was restructured at the Canadian Memorial Chiropractic College is chronicled. Method: A Delphi process used to restructure the course is described, and the results of a student satisfaction survey are presented. Results: When asked “I think this material was clinically relevant,” over 81% of the 76 students who respondents strongly agreed or agreed with this statement; 100% of students agreed or strongly agreed that scope of practice; marketing, advertising and internal office promotion; record keeping; fee schedules; malpractice issues and; professional malpractice issues and negligence was clinically relevant. When asked “I think this material was taught well,” a minimum of 89% of students agreed or strongly agreed with this statement. Discussion: This is the first article published that described the process by which a jurisprudence course was developed and assessed by student survey. Summary: Based on a survey of student perceptions, restructuring of the jurisprudence course was successful in providing students with clinically relevant information in an appropriate manner. This course may serve as an important first step in development a ‘model curriculum’ for chiropractic practice and the law courses in terms of content, format and assessment strategies. PMID:20195427
The Structure of the Narcissistic Personality Inventory With Binary and Rating Scale Items.
Boldero, Jennifer M; Bell, Richard C; Davies, Richard C
2015-01-01
Narcissistic Personality Inventory (NPI) items typically have a forced-choice format, comprising a narcissistic and a nonnarcissistic statement. Recently, some have presented the narcissistic statements and asked individuals to either indicate whether they agree or disagree that the statements are self-descriptive (i.e., a binary response format) or to rate the extent to which they agree or disagree that these statements are self-descriptive on a Likert scale (i.e., a rating response format). The current research demonstrates that when NPI items have a binary or a rating response format, the scale has a bifactor structure (i.e., the items load on a general factor and on 6 specific group factors). Indexes of factor strength suggest that the data are unidimensional enough for the NPI's general factor to be considered a measure of a narcissism latent trait. However, the rating item general factor assessed more narcissism components than the binary item one. The positive correlations of the NPI's general factor, assessed when items have a rating response format, were moderate with self-esteem, strong with a measure of narcissistic grandiosity, and weak with 2 measures of narcissistic vulnerability. Together, the results suggest that using a rating format for items enhances the information provided by the NPI.
Optimum data weighting and error calibration for estimation of gravitational parameters
NASA Technical Reports Server (NTRS)
Lerch, F. J.
1989-01-01
A new technique was developed for the weighting of data from satellite tracking systems in order to obtain an optimum least squares solution and an error calibration for the solution parameters. Data sets from optical, electronic, and laser systems on 17 satellites in GEM-T1 (Goddard Earth Model, 36x36 spherical harmonic field) were employed toward application of this technique for gravity field parameters. Also, GEM-T2 (31 satellites) was recently computed as a direct application of the method and is summarized here. The method employs subset solutions of the data associated with the complete solution and uses an algorithm to adjust the data weights by requiring the differences of parameters between solutions to agree with their error estimates. With the adjusted weights the process provides for an automatic calibration of the error estimates for the solution parameters. The data weights derived are generally much smaller than corresponding weights obtained from nominal values of observation accuracy or residuals. Independent tests show significant improvement for solutions with optimal weighting as compared to the nominal weighting. The technique is general and may be applied to orbit parameters, station coordinates, or other parameters than the gravity model.
Spontaneous Fission Barriers Based on a Generalized Liquid Drop Model
NASA Astrophysics Data System (ADS)
Guo, Shu-Qing; Bao, Xiao-Jun; Li, Jun-Qing; Zhang, Hong-Fei
2014-05-01
The barrier against the spontaneous fission has been determined within the Generalized Liquid Drop Model (GLDM) including the mass and charge asymmetry, and the proximity energy. The shell correction of the spherical parent nucleus is calculated by using the Strutinsky method, and the empirical shape-dependent shell correction is employed during the deformation process. A quasi-molecular shape sequence has been defined to describe the whole process from one-body shape to two-body shape system, and a two-touching-ellipsoid is adopted when the superdeformed one-body system reaches the rupture point. On these bases the spontaneous fission barriers are systematically studied for nuclei from 230Th to 249Cm for different possible exiting channels with the different mass and charge asymmetries. The double, and triple bumps are found in the fission potential energy in this region, which roughly agree with the experimental results. It is found that at around Sn-like fragment the outer fission barriers are lower, while the partner of the Sn-like fragment is in the range near 108Ru where the ground-state mass is lowered by allowing axially symmetric shapes. The preferable fission channels are distinctly pronounced, which should be corresponding to the fragment mass distributions.
You can’t teach speed: sprinters falsify the deliberate practice model of expertise
Deaner, Robert O.
2014-01-01
Many scientists agree that expertise requires both innate talent and proper training. Nevertheless, the highly influential deliberate practice model (DPM) of expertise holds that talent does not exist or makes a negligible contribution to performance. It predicts that initial performance will be unrelated to achieving expertise and that 10 years of deliberate practice is necessary. We tested these predictions in the domain of sprinting. In Studies 1 and 2 we reviewed biographies of 15 Olympic champions and the 20 fastest American men in U.S. history. In all documented cases, sprinters were exceptional prior to initiating training, and most reached world class status rapidly (Study 1 median = 3 years; Study 2 = 7.5). In Study 3 we surveyed U.S. national collegiate championships qualifiers in sprinters (n = 20) and throwers (n = 44). Sprinters recalled being faster as youths than did throwers, whereas throwers recalled greater strength and throwing ability. Sprinters’ best performances in their first season of high school, generally the onset of formal training, were consistently faster than 95–99% of their peers. Collectively, these results falsify the DPM for sprinting. Because speed is foundational for many sports, they challenge the DPM generally. PMID:25024914
Diurnal variation of O3, ClO, HOCl, HO2, and BrO observed by JEM/SMILES
NASA Astrophysics Data System (ADS)
Suzuki, Makoto; Mitsuda, Chihiro; Manago, Naohiro; Imai, Koji; Sakazaki, Takatoshi; Ozeki, Hiroyuki; Nishimoto, Eriko; Naito, Yoko; Akiyoshi, Hidehary; Kinnison, Douglas; Sano, Takuki; Shiotani, Masato
2013-04-01
SMILES; Superconducting Submillimeter-Wave Limb Emission Sounder is a 4 K cooled 625-650 GHz limb sounder to observe O3, HCl, ClO, HO2, HOCl, BrO, HNO3, and O3 isotopes. SMILES had been operated on the International Space Station from Oct. 12, 2009 to Apr. 21, 2010. Since ISS is 51° inclined orbit, 30-45 days SMILES zonal mean could provide diurnal variation of chemical species in the stratosphere and mesosphere. Diurnal variation of O3, ClO, HOCl, HO2, and BrO are compared with two nudged CGCM calculations (SD-WACCM; Specified-dynamics WACCM, and MIROC) and satellite observations. Diurnal variation of O3 agreed with SD-WACCM over 50-82 km, but small peak in the morning (7 am local time) is apparent for the SMILES but not for the SD-WACCM at 70 km. Diurnal variation of ClO agreed quite well between SMILES L2 ver. 2.2 and SD-WACCM from 19 to 76 km altitude region. But nighttime ClO value of SMILES L2 ver. 2,2 above 50 km is less than SD-WACCM (70%), which is not clearly explained by the SMILES retrieval issue or our current knowledge of chemical kinetics. Diurnal variation of HOCl also agreed quite nicely from 31 to 76 km. SMILES HOCl retrieval is difficult since it is strongly affected by nearby O3 isotope and O3 hot band lines, as well as very strong HCl line. The nighttime build up of HOCl observed SMILES at 44-68 km are nicely reproduced by the SD-WACCM calculation using JPL2006 chemical kinetics dataset. But chemical kinetics calculation using SMILES ClO, HO2, and HOCl at 35-45 km altitude supported much faster reaction rate of ClO + HO2 given by JPL2010. HO2 diurnal variation also agreed with SD-WACCM from 24 to 72 km. Above 76 km, SMILES L2 ver. 2.2 needs modification of a priori and its co-variance, and we will get better agreement with model calculations. SMILES L2 ver. 2.2 also shows night time bias due to AOS (Acousto-Optics Spectrometer) characteristics. SMILES Band C BrO observation is strongly interfered by overlapping O3 isotope lines, and it is currently under test retrieval stage. SMILES BrO L2 ver. 2.2 looks appropriate (answering independent of a priori value) from 19 to 64 km. After the sunset build-up and slow nighttime decay of BrO observed SMLES L2 ver. 2.2 agreed well with SD-WACCM. SMILES BrO value has negative bias from 25 to 37 km, and it should be subtracted for scientific usage. In general, SMILES L2 ver. 2.2 agreed well with SD-WACCM calculation. Agreement with MIROC is much less since the MIROC model use simplified chemistry package. We believe that the SMILES and SD-WACCM agreement is not false (a priori origin) but both SMILES observation and CGCM calculation made by SD-WACCM are enough precise and accurate.
NASA Technical Reports Server (NTRS)
Cunningham, Herbert J.
1987-01-01
The body surface-panel method SOUSSA is applied to calculate steady and unsteady lift and pitching moment coefficients on a thin fighter-type wing model with and without a tip-mounted missile. Comparisons are presented with experimental results and with PANAIR and PANAIR-related calculations for Mach numbers from 0.6 to 0.9. In general the SOUSSA program, the experiments, and the PANAIR (and related) programs give lift and pitching-moment results which agree at least fairly well, except for the unsteady clean-wing experimental moment and the unsteady moment on the wing tip body calculated by a PANAIR-predecessor program at a Mach number of 0.8.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Çağlar, Halife, E-mail: hlfcglr@gmail.com; Aygün, Sezgin, E-mail: saygun@comu.edu.tr
In this study, we have investigated bulk viscous with strange quark matter attached to the string cloud for higher dimensional Friedman-Robertson-Walker (FRW) universe in Lyra geometry. By using varying deceleration parameter and conservation equations we have solved Einstein Field Equations (EFE’s) and obtained generalized exact solutions for our model. Also we have found that string is not survived for bulk viscous with strange quark matter attached to the string cloud in framework higher dimensional FRW universe in Lyra geometry. This result agrees with Kiran and Reddy, Krori et al, Sahoo and Mishra and Mohanty et al. in four and fivemore » dimensions.« less
Epidemic extinction paths in complex networks
NASA Astrophysics Data System (ADS)
Hindes, Jason; Schwartz, Ira B.
2017-05-01
We study the extinction of long-lived epidemics on finite complex networks induced by intrinsic noise. Applying analytical techniques to the stochastic susceptible-infected-susceptible model, we predict the distribution of large fluctuations, the most probable or optimal path through a network that leads to a disease-free state from an endemic state, and the average extinction time in general configurations. Our predictions agree with Monte Carlo simulations on several networks, including synthetic weighted and degree-distributed networks with degree correlations, and an empirical high school contact network. In addition, our approach quantifies characteristic scaling patterns for the optimal path and distribution of large fluctuations, both near and away from the epidemic threshold, in networks with heterogeneous eigenvector centrality and degree distributions.
Epidemic extinction paths in complex networks.
Hindes, Jason; Schwartz, Ira B
2017-05-01
We study the extinction of long-lived epidemics on finite complex networks induced by intrinsic noise. Applying analytical techniques to the stochastic susceptible-infected-susceptible model, we predict the distribution of large fluctuations, the most probable or optimal path through a network that leads to a disease-free state from an endemic state, and the average extinction time in general configurations. Our predictions agree with Monte Carlo simulations on several networks, including synthetic weighted and degree-distributed networks with degree correlations, and an empirical high school contact network. In addition, our approach quantifies characteristic scaling patterns for the optimal path and distribution of large fluctuations, both near and away from the epidemic threshold, in networks with heterogeneous eigenvector centrality and degree distributions.
Detecting temperature fluctuations at equilibrium.
Dixit, Purushottam D
2015-05-21
The Gibbs and the Boltzmann definition of temperature agree only in the macroscopic limit. The ambiguity in identifying the equilibrium temperature of a finite-sized 'small' system exchanging energy with a bath is usually understood as a limitation of conventional statistical mechanics. We interpret this ambiguity as resulting from a stochastically fluctuating temperature coupled with the phase space variables giving rise to a broad temperature distribution. With this ansatz, we develop the equilibrium statistics and dynamics of small systems. Numerical evidence using an analytically tractable model shows that the effects of temperature fluctuations can be detected in the equilibrium and dynamical properties of the phase space of the small system. Our theory generalizes statistical mechanics to small systems relevant in biophysics and nanotechnology.
Very high energy gamma ray astronomy
NASA Technical Reports Server (NTRS)
Grindlay, J. E.
1976-01-01
Recent results in ground based very high energy gamma ray astronomy are reviewed. The various modes of the atmospheric Cerenkov technique are described, and the importance of cosmic ray rejection methods is stressed. The positive detections of the Crab pulsar that suggest a very flat spectrum and time-variable pulse phase are discussed. Observations of other pulsars (particularly Vela) suggest these features may be general. Evidence that a 4.8 hr modulated effect was detected from Cyg X-3 is strengthened in that the exact period originally proposed agrees well with a recent determination of the X-ray period. The southern sky observations are reviewed, and the significance of the detection of an active galaxy (NGC 5128) is considered for source models and future observations.
Relativistic effects in electron impact ionization from the p-orbital
NASA Astrophysics Data System (ADS)
Haque, A. K. F.; Uddin, M. A.; Basak, A. K.; Karim, K. R.; Saha, B. C.; Malik, F. B.
2006-06-01
The parameters of our recent modification of BELI formula (MBELL) [A.K.F. Haque, M.A. Uddin, A.K. Basak, K.R. Karim, B.C. Saha, Phys. Rev. A 73 (2006) 012708] are generalized in terms of the orbital quantum numbers nl to evaluate the electron impact ionization (EII) cross sections of a wide range of isoelectronic targets (H to Ne series) and incident energies. For both the open and closed p-shell targets, the present MBELL results with a single parameter set, agree nicely with the experimental cross sections. The relativistic effect of ionization in the 2p subshell of U82+ for incident energies up to 250 MeV is well accounted for by the prescribed parameters of the model.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bloom, Aaron; Townsend, Aaron; Palchak, David
Balancing wind and solar in a model is relatively easy. All you need to do is assume a very large system with infinite flexibility! But what if you don't have an infinitely flexible system? What if there are thousands of generators nestled in a handful of regions that are unlikely to change their operational practices? Would you still have enough flexibility to balance hundreds of gigawatts of wind and solar at a 5 minute level? At NREL, we think we can, and our industry partners agree. This presentation was presented at the IEEE Power and Energy Society General Meeting bymore » Aaron Bloom, highlighting results of the Eastern Renewable Generation Integration Study.« less
Evaluation of ConPrim: A three-part model for continuing education in primary health care.
Berggren, Erika; Strang, Peter; Orrevall, Ylva; Ödlund Olin, Ann; Sandelowsky, Hanna; Törnkvist, Lena
2016-11-01
To overcome the gap between existing knowledge and the application of this knowledge in practice, a three-part continuing educational model for primary health care professionals (ConPrim) was developed. It includes a web-based program, a practical exercise and a case seminar. To evaluate professionals' perceptions of the design, pedagogy and adaptation to primary health care of the ConPrim continuing educational model as applied in a subject-specific intervention. A total of 67 professionals (nurses and physicians) completed a computer-based questionnaire evaluating the model's design, pedagogy and adaptation to primary health care one week after the intervention. Descriptive statistics were used. Over 90% found the design of the web-based program and case seminar attractive; 86% found the design of the practical exercise attractive. The professionals agreed that the time spent on two of the three parts was acceptable. The exception was the practical exercise: 32% did not fully agree. Approximately 90% agreed that the contents of all parts were relevant to their work and promoted interactive and interprofessional learning. In response to the statements about the intervention as whole, approximately 90% agreed that the intervention was suitable to primary health care, that it had increased their competence in the subject area, and that they would be able to use what they had learned in their work. ConPrim is a promising model for continuing educational interventions in primary health care. However, the time spent on the practical exercise should be adjusted and the instructions for the exercise clarified. ConPrim should be tested in other subject-specific interventions and its influence on clinical practice should be evaluated. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Modelling the core magnetic field of the earth
NASA Technical Reports Server (NTRS)
Harrison, C. G. A.; Carle, H. M.
1982-01-01
It is suggested that radial off-center dipoles located within the core of the earth be used instead of spherical harmonics of the magnetic potential in modeling the core magnetic field. The off-center dipoles, in addition to more realistically modeling the physical current systems within the core, are if located deep within the core more effective at removing long wavelength signals of either potential or field. Their disadvantage is that their positions and strengths are more difficult to compute, and such effects as upward and downward continuation are more difficult to manipulate. It is nevertheless agreed with Cox (1975) and Alldredge and Hurwitz (1964) that physical realism in models is more important than mathematical convenience. A radial dipole model is presented which agrees with observations of secular variation and excursions.
Big bang nucleosynthesis - The standard model and alternatives
NASA Technical Reports Server (NTRS)
Schramm, David N.
1991-01-01
The standard homogeneous-isotropic calculation of the big bang cosmological model is reviewed, and alternate models are discussed. The standard model is shown to agree with the light element abundances for He-4, H-2, He-3, and Li-7 that are available. Improved observational data from recent LEP collider and SLC results are discussed. The data agree with the standard model in terms of the number of neutrinos, and provide improved information regarding neutron lifetimes. Alternate models are reviewed which describe different scenarios for decaying matter or quark-hadron induced inhomogeneities. The baryonic density relative to the critical density in the alternate models is similar to that of the standard model when they are made to fit the abundances. This reinforces the conclusion that the baryonic density relative to critical density is about 0.06, and also reinforces the need for both nonbaryonic dark matter and dark baryonic matter.
Dynamic Smagorinsky model on anisotropic grids
NASA Technical Reports Server (NTRS)
Scotti, A.; Meneveau, C.; Fatica, M.
1996-01-01
Large Eddy Simulation (LES) of complex-geometry flows often involves highly anisotropic meshes. To examine the performance of the dynamic Smagorinsky model in a controlled fashion on such grids, simulations of forced isotropic turbulence are performed using highly anisotropic discretizations. The resulting model coefficients are compared with a theoretical prediction (Scotti et al., 1993). Two extreme cases are considered: pancake-like grids, for which two directions are poorly resolved compared to the third, and pencil-like grids, where one direction is poorly resolved when compared to the other two. For pancake-like grids the dynamic model yields the results expected from the theory (increasing coefficient with increasing aspect ratio), whereas for pencil-like grids the dynamic model does not agree with the theoretical prediction (with detrimental effects only on smallest resolved scales). A possible explanation of the departure is attempted, and it is shown that the problem may be circumvented by using an isotropic test-filter at larger scales. Overall, all models considered give good large-scale results, confirming the general robustness of the dynamic and eddy-viscosity models. But in all cases, the predictions were poor for scales smaller than that of the worst resolved direction.
The octave illusion revisited again.
Deutsch, Diana
2004-04-01
The octave illusion (D. Deutsch, 1974) occurs when 2 tones separated by an octave are alternated repeatedly, such that when the right ear receives the high tone, the left ear receives the low tone, and vice versa. Most subjects in the original study reported hearing a single tone that alternated from ear to ear, whose pitch also alternated from octave to octave, and D. Deutsch (1975a) proposed an explanation in terms of separate what and where auditory pathways. C. D. Chambers, J. B. Mattingley, and S. A. Moss (2002) argued that the perceived pitch difference generally corresponds more to a semitone and proposed an alternative explanation in terms of diplacusis. This article argues that Chambers et al. used problematic procedures and reports a new experiment on the octave illusion. The findings confirm that an octave difference is generally perceived, and they agree with the model of Deutsch (1975a) but are at variance with the diplacusis hypothesis. ((c) 2004 APA, all rights reserved)
Ebert, Tanya; Zolotov, Yuval; Eliav, Shani; Ginzburg, Orit; Shapira, Irena; Magnezi, Racheli
2015-07-01
Cannabis has been used throughout history for different purposes but was outlawed in the United States in 1937; many countries followed suit. Although recently reintroduced as a medical treatment in several countries, the use of cannabis in Israel is permitted for some medical purposes but is still controversial, eliciting heated public and professional debate. The few published studies on physicians' attitudes to medical cannabis found them to be generally unsupportive. To examine, for the first time, the experience, knowledge and attitudes of Israeli physicians towards medical cannabis (MC). A 32 item questionnaire reflected physicians' demographics, knowledge of and experience with MC and their attitudes to this treatment. Seventy-two physicians participated in this study. Physicians generally agreed that MC treatment could be helpful for chronic and for terminally ill patients (n = 61, 79.2%). Oncologists and pain specialists did not agree unanimously that MC can undermine mental health, whereas other physicians did (P < 0.001, df = 4). Physicians who recommended MC in the past (once or more) agreed, more than physicians who did not, with the statement "MC treatment in Israel is accessible to patients who need it" (P < 0.05, df = 2). In contrast to other studies we found partial acceptance of MC as a therapeutic agent. Further in-depth studies are needed to address regulatory and educational needs.
QUALITY ASSURANCE AND QUALITY CONTROL FOR WASTE CONTAINMENT FACILITIES. Project Summary
It is generally agreed that both quality assurance (QA) and quality control (QC) are essential to the proper installation and eventual performance of environmentally safe and secure waste containment systems. Even further, there are both manufacturing and construction aspects to...
Foreign Language Teacher Education. ERIC Digest.
ERIC Educational Resources Information Center
Jarvis, Gilbert A.; Bernhardt, Elizabeth B.
Foreign language education professionals agree that the profession lacks an established theory and methodological consistency. Foreign language teacher education has not changed much since the 1960s. Most programs consist of subject-matter content, general education requirements, and specialized education courses. Teacher trainee supervisors do…
Srinivasan, Arjun; Song, Xiaoyan; Richards, Ann; Sinkowitz-Cochran, Ronda; Cardo, Denise; Rand, Cynthia
2004-07-12
Examination of knowledge, attitudes, and beliefs of house staff physicians will be important in developing interventions to improve antimicrobial use and prevent resistance. A 75-item survey was distributed to house staff physicians on nonpediatric services in a university teaching hospital. Knowledge was assessed with a 10-question quiz. The survey was completed by 179 (67%) of 269 house staff physicians on 5 specialties. Outside and inside the intensive care unit, 21% and 25% of respondents, respectively, reported that they were using antibiotics optimally. Surgeons were significantly more likely than other physicians to report that they were regularly seeking input into antimicrobial selections (P<.001). Of the 170 physicians who completed the survey, 88% agreed antibiotics are overused in general and 72% also agreed this was the case at their institution (r = 0.56; P<.05); 96% agreed that hospitals in general face serious problems with antibiotic resistance and 93% agreed that their hospital faces these same problems (r = 0.57; P<.05); 97% agreed that better use of antibiotics would reduce resistance; 32% stated that they had not had formal teaching on antimicrobial agents in the last year (medicine residents reported significantly more formal teaching than others [P =.001]); and 90% wanted more education about antimicrobials and 67% wanted more feedback on antimicrobial selections. The mean antimicrobial quiz score was 28%, with medicine residents scoring significantly higher than others (P =.04). Upper-level residents did not perform better than interns. This survey (1) revealed that house staff are aware of the importance of antimicrobial resistance and believe better antimicrobial use will help this problem and (2) demonstrated differences between specialties with respect to antimicrobial use and knowledge. House staff at our hospital have suboptimal knowledge about antimicrobials, and this knowledge did not increase appreciably over the course of their training. Antimicrobial education is needed and is likely to be well received by house staff physicians in academic centers but may be more effective if it is tailored to specific specialties.
Miksys, N; Xu, C; Beaulieu, L; Thomson, R M
2015-08-07
This work investigates and compares CT image metallic artifact reduction (MAR) methods and tissue assignment schemes (TAS) for the development of virtual patient models for permanent implant brachytherapy Monte Carlo (MC) dose calculations. Four MAR techniques are investigated to mitigate seed artifacts from post-implant CT images of a homogeneous phantom and eight prostate patients: a raw sinogram approach using the original CT scanner data and three methods (simple threshold replacement (STR), 3D median filter, and virtual sinogram) requiring only the reconstructed CT image. Virtual patient models are developed using six TAS ranging from the AAPM-ESTRO-ABG TG-186 basic approach of assigning uniform density tissues (resulting in a model not dependent on MAR) to more complex models assigning prostate, calcification, and mixtures of prostate and calcification using CT-derived densities. The EGSnrc user-code BrachyDose is employed to calculate dose distributions. All four MAR methods eliminate bright seed spot artifacts, and the image-based methods provide comparable mitigation of artifacts compared with the raw sinogram approach. However, each MAR technique has limitations: STR is unable to mitigate low CT number artifacts, the median filter blurs the image which challenges the preservation of tissue heterogeneities, and both sinogram approaches introduce new streaks. Large local dose differences are generally due to differences in voxel tissue-type rather than mass density. The largest differences in target dose metrics (D90, V100, V150), over 50% lower compared to the other models, are when uncorrected CT images are used with TAS that consider calcifications. Metrics found using models which include calcifications are generally a few percent lower than prostate-only models. Generally, metrics from any MAR method and any TAS which considers calcifications agree within 6%. Overall, the studied MAR methods and TAS show promise for further retrospective MC dose calculation studies for various permanent implant brachytherapy treatments.
De Lorenzo, Robert A; Abbott, Cynthia A
2004-01-01
Until recently, the U.S. Army Combat Medic School used a traditional teaching model with heavy emphasis on large group lectures. Skills were taught separately with minimal links to didactics. To evaluate whether the adult learning model improves student learning in terms of cognitive performance and perception of proficiency in military medic training. The study population was two sequential groups of randomly selected junior, enlisted, active duty soldiers with no prior formal emergency medical training who were enrolled in an experimental model of a U.S. Army Combat Medic School. The control population was a similar group of students enrolled in the traditional curriculum. Instructors were drawn from the same pool, with experimental group instructors receiving two weeks of training in adult-learning strategies. The study population was enrolled in the experimental program that emphasized the principles of adult learning, including small-group interactive approach, self-directed study, multimedia didactics, and intensive integrated practice of psychomotor skills. Instructors and students were also surveyed at the end of the course as to their confidence in performing four critical skills. The survey instrument used a five-point scale ranging from "strongly disagree" through "undecided" to "strongly agree." Proficiency for this survey was defined as the sum of the top two ratings of "agree" or "strongly agree" to questions regarding the particular skill. Both experimental and control programs lasted ten weeks and covered the same academic content and nonacademic (e.g., physical fitness) requirements, and the two groups of students had similar duty days. Evaluations included performance on internal and National Registry of Emergency Medical Technicians (NREMT) written examinations and other measures of academic and nonacademic performance. One hundred fifty students (experimental n = 81, control n = 69) were enrolled in 1999-2000. The scores for internal course grade, NREMT written score, and NREMT written pass rate were, respectively, 86.3, 71.6, and 63% for the experimental group; and 85.8, 69.6, and 49% for the control group. The p-value was = 0.05 for the comparison between internal course grade and NREMT written score, but p > 0.05 for the comparison between NREMT written pass rates. Students in both the adult-learning and traditional groups rated themselves high in proficiency, whereas instructors in the traditional group were generally much more modest in their rating of student proficiency than instructors of the adult-learning program. In this study setting, an adult-learning model offers only a modest improvement in cognitive evaluation scores over traditional teaching when measured at the end of the course. Additionally, students in the traditional teaching model assess themselves as proficient more frequently than instructors, whereas instructor and student perception of proficiency more closely matched in the adult-learning model.
Breast self-examination: Resistance to change
Del Giudice, M. Elisabeth; Tannenbaum, David; Goodwin, Pamela J.
2005-01-01
OBJECTIVE To investigate whether Canadian family practitioners routinely teach breast self-examination (BSE) after publication of the 2001 Canadian Preventive Health Task Force guideline advising them to exclude teaching BSE from periodic health examinations. DESIGN Self-administered cross-sectional mailed survey. SETTING Canada. PARTICIPANTS A random sample of English-speaking general practitioners and physicians certified by the College of Family Physicians of Canada. MAIN OUTCOME MEASURES Current and past BSE practices and opinions on the value of BSE. RESULTS Response rate was 47.4%. Most respondents (88%) were aware of the new recommendations, yet only 16% had changed their usual practice of routinely teaching BSE. Most physicians agreed that before the recommendation they almost always taught BSE (74.3%). Only 9.5% agreed that physicians should follow the recommendation and not routinely teach BSE. A few also agreed that they now spend less time discussing BSE (25.7%) and that the recommendation has influenced them to stop teaching (12.4%) and encouraging (12.9%) women to practise BSE. Physicians who had changed their BSE practices were less likely to agree that BSE increases early detection of breast cancer and more likely to agree that BSE increases benign breast biopsies. They were also more likely to agree that screening mammography in women older than 50 decreases mortality from breast cancer. CONCLUSION This survey, which assessed routine teaching of BSE, revealed poor adherence by Canadian family physicians to a well publicized evidence-based guideline update. Resistance to change could in part be attributed to a lack of knowledge of the supporting evidence, a lack of confidence in the evidence to date, and personal experiences with patients within their practices. PMID:16926925
Andersen, Merethe K; Christensen, Bo; Søndergaard, Jens
2013-10-11
Care for overweight children in general practice involves collaboration with parents. Acknowledging the parents' frames of references is a prerequisite for successful management. We therefore aimed to analyse parental beliefs about the presumed causes and consequences of overweight in children and expectations towards the GP. Moreover, we aimed at comparing the beliefs and expectations of parents of non-overweight children (NOWC) and parents of overweight children (OWC). A cross-sectional survey. Data were obtained from a questionnaire exploring parents' beliefs and expectations regarding overweight in children. The questionnaires were completed by parents following their child's participation in the five-year preventive child health examination (PCHE).Parental agreement upon statements concerning beliefs and expectations regarding overweight in children was measured on a Likert scale. Differences in levels of agreement between parents of non-overweight children and parents of overweight children were analysed using Chi-squared test and Fisher's exact test. Parents of 879 children completed and returned questionnaires. Around three fourths of the parents agreed that overweight was a health problem. A majority of parents (93%) agreed that the GP should call attention to overweight in children and offer counselling on diet and exercise. Almost half of the parents expected a follow-up programme. Parents of overweight children seemed to agree less upon some of the proposed causes of overweight, e.g. inappropriate diet and lack of exercise. These parents also had stronger beliefs about overweight disappearing by itself as the child grows up. According to parental beliefs and expectations, general practice should have an important role to play in the management of child overweight. Moreover, our findings suggest that GPs should be aware of the particular beliefs that parents of overweight children may have regarding causes of overweight in their child.
Bamberger, Simon Grandjean; Larsen, Anelia; Vinding, Anker Lund; Nielsen, Peter; Fonager, Kirsten; Nielsen, René Nesgaard; Ryom, Pia; Omland, Øyvind
2015-01-01
Work intensification is a popular management strategy to increase productivity, but at the possible expense of employee mental stress. This study examines associations between ratings of work intensification and psychological distress, and the level of agreement between compared employee-rated and manager-rated work intensification. Multi-source survey data were collected from 3,064 employees and 573 company managers from the private sector in 2010. Multilevel regression models were used to compare different work intensification ratings across psychological distress strata. Distressed employees rated higher degree of total work intensification compared to non-distressed employees, and on three out of five sub ratings there were an increased prevalence of work intensification in the case group. In general, there was poor agreement between employee and company work intensification rating. Neither manager-rated work intensification nor employee/manager discrepancy in work intensification ratings was associated with psychological distress. Distressed employees had a higher total score of employee/manager agreed work intensification, and a higher prevalence of increased demands of labour productivity. This study demonstrates higher ratings of employee/manager agreed work intensification in distressed employees compared to non-distressed employees, challenging previous findings of reporting bias in distressed employees' assessment of work environment.
BAMBERGER, Simon Grandjean; LARSEN, Anelia; VINDING, Anker Lund; NIELSEN, Peter; FONAGER, Kirsten; NIELSEN, René Nesgaard; RYOM, Pia; OMLAND, Øyvind
2015-01-01
Work intensification is a popular management strategy to increase productivity, but at the possible expense of employee mental stress. This study examines associations between ratings of work intensification and psychological distress, and the level of agreement between compared employee-rated and manager-rated work intensification. Multi-source survey data were collected from 3,064 employees and 573 company managers from the private sector in 2010. Multilevel regression models were used to compare different work intensification ratings across psychological distress strata. Distressed employees rated higher degree of total work intensification compared to non-distressed employees, and on three out of five sub ratings there were an increased prevalence of work intensification in the case group. In general, there was poor agreement between employee and company work intensification rating. Neither manager-rated work intensification nor employee/manager discrepancy in work intensification ratings was associated with psychological distress. Distressed employees had a higher total score of employee/manager agreed work intensification, and a higher prevalence of increased demands of labour productivity. This study demonstrates higher ratings of employee/manager agreed work intensification in distressed employees compared to non-distressed employees, challenging previous findings of reporting bias in distressed employees’ assessment of work environment. PMID:25752252
NASA Astrophysics Data System (ADS)
Ohyanagi, S.; Dileonardo, C.
2013-12-01
As a natural phenomenon earthquake occurrence is difficult to predict. Statistical analysis of earthquake data was performed using candlestick chart and Bollinger Band methods. These statistical methods, commonly used in the financial world to analyze market trends were tested against earthquake data. Earthquakes above Mw 4.0 located on shore of Sanriku (37.75°N ~ 41.00°N, 143.00°E ~ 144.50°E) from February 1973 to May 2013 were selected for analysis. Two specific patterns in earthquake occurrence were recognized through the analysis. One is a spread of candlestick prior to the occurrence of events greater than Mw 6.0. A second pattern shows convergence in the Bollinger Band, which implies a positive or negative change in the trend of earthquakes. Both patterns match general models for the buildup and release of strain through the earthquake cycle, and agree with both the characteristics of the candlestick chart and Bollinger Band analysis. These results show there is a high correlation between patterns in earthquake occurrence and trend analysis by these two statistical methods. The results of this study agree with the appropriateness of the application of these financial analysis methods to the analysis of earthquake occurrence.
Introduction of a continuing professional development tool for preceptors: lessons learned.
Tofade, Toyin; Kim, Jane; Lebovitz, Lisa; Leadon, Kim; Maynor, Lena; Culhane, Nicole; Freeberry, Mark; Harris, JoAnn Stacy; Abate, Marie
2015-04-01
Accreditation Council for Pharmacy Education (ACPE) guidelines state that preceptors should "have a systematic, self-directed approach to their own continuing professional development (CPD)." The objective of this study was to encourage preceptors to take advantage of the ACPE CPD resources and implement the concept of CPD (reflect, plan, act, evaluate, record) as a framework for guiding individual preceptor's continuing development as educators and to determine their opinion regarding the usefulness, effectiveness, and obstacles to implementation of this approach. A total of 3713 preceptors from the participating schools were encouraged to undergo CPD training and invited to respond to a series of questions. Of the initial respondents, 48% represented health system/hospital preceptors, followed by community/independent pharmacists (64 of 236, 28%). Preceptor respondents often train students from multiple schools/colleges (average = 1.9 schools/colleges per preceptor) and 90% agreed or strongly agreed with the statement, "the CPD model, as learned in the webcasts, is beneficial for ongoing preceptor development." The general consensus was that the preceptor portfolio provided motivation to reflect, plan, and set more defined and realistic goals for students, residents, and themselves as educators and could be a valuable starting point for promoting preceptors' reflection, planning, and action related to rotation management, professional teaching, and student learning goals. © The Author(s) 2014.
Consumer product chemical weight fractions from ingredient lists.
Isaacs, Kristin K; Phillips, Katherine A; Biryol, Derya; Dionisio, Kathie L; Price, Paul S
2018-05-01
Assessing human exposures to chemicals in consumer products requires composition information. However, comprehensive composition data for products in commerce are not generally available. Many consumer products have reported ingredient lists that are constructed using specific guidelines. A probabilistic model was developed to estimate quantitative weight fraction (WF) values that are consistent with the rank of an ingredient in the list, the number of reported ingredients, and labeling rules. The model provides the mean, median, and 95% upper and lower confidence limit WFs for ingredients of any rank in lists of any length. WFs predicted by the model compared favorably with those reported on Material Safety Data Sheets. Predictions for chemicals known to provide specific functions in products were also found to reasonably agree with reported WFs. The model was applied to a selection of publicly available ingredient lists, thereby estimating WFs for 1293 unique ingredients in 1123 products in 81 product categories. Predicted WFs, although less precise than reported values, can be estimated for large numbers of product-chemical combinations and thus provide a useful source of data for high-throughput or screening-level exposure assessments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mack, J H; Dibble, R W; Buchholz, B A
2004-01-16
Despite the rapid combustion typically experienced in Homogeneous Charge Compression Ignition (HCCI), components in fuel mixtures do not ignite in unison or burn equally. In our experiments and modeling of blends of diethyl ether (DEE) and ethanol (EtOH), the DEE led combustion and proceeded further toward completion, as indicated by {sup 14}C isotope tracing. A numerical model of HCCI combustion of DEE and EtOH mixtures supports the isotopic findings. Although both approaches lacked information on incompletely combusted intermediates plentiful in HCCI emissions, the numerical model and {sup 14}C tracing data agreed within the limitations of the single zone model. Despitemore » the fact that DEE is more reactive than EtOH in HCCI engines, they are sufficiently similar that we did not observe a large elongation of energy release or significant reduction in inlet temperature required for light-off, both desired effects for the combustion event. This finding suggests that, in general, HCCI combustion of fuel blends may have preferential combustion of some of the blend components.« less
Prediction of Thrombus Growth: Effect of Stenosis and Reynolds Number.
Hosseinzadegan, Hamid; Tafti, Danesh K
2017-06-01
Shear stresses play a major role in platelet-substrate interactions and thrombus formation and growth in blood flow, where under both pathological and physiological conditions platelet adhesion and accumulation occur. In this study, a shear-dependent continuum model for platelet activation, adhesion and aggregation is presented. The model was first verified under three different shear conditions and at two heparin levels. Three-dimensional simulations were then carried out to evaluate the performance of the model for severely damaged (stripped) aortas with mild and severe stenosis degrees in laminar flow regime. For these cases, linear shear-dependent functions were developed for platelet-surface and platelet-platelet adhesion rates. It was confirmed that the platelet adhesion rate is not only a function of Reynolds number (or wall shear rate) but also the stenosis severity of the vessel. General correlations for adhesion rates of platelets as functions of stenosis and Reynolds number were obtained based on these cases. Finally using the new platelet adhesion rates, the model was applied to different experimental systems and shown to agree well with measured platelet deposition.
Analysis of an unswept propfan blade with a semiempirical dynamic stall model
NASA Technical Reports Server (NTRS)
Reddy, T. S. R.; Kaza, K. R. V.
1989-01-01
The time history response of a propfan wind tunnel model with dynamic stall is studied analytically. The response obtained from the analysis is compared with available experimental data. The governing equations of motion are formulated in terms of blade normal modes which are calculated using the COSMIC-NASTRAN computer code. The response analysis considered the blade plunging and pitching motions. The lift, drag and moment coefficients for angles of attack below the static stall angle are obtained from a quasi-steady theory. For angles above static stall angles, a semiempirical dynamic stall model based on a correction to angle of attack is used to obtain lift, drag and moment coefficients. Using these coefficients, the aerodynamic forces are calculated at a selected number of strips, and integrated to obtain the total generalized forces. The combined momentum-blade element theory is used to calculate the induced velocity. The semiempirical stall model predicted a limit cycle oscillation near the setting angle at which large vibratory stresses were observed in an experiment. The predicted mode and frequency of oscillation also agreed with those measured in the experiment near the setting angle.
Analysis of JT-60SA operational scenarios
NASA Astrophysics Data System (ADS)
Garzotti, L.; Barbato, E.; Garcia, J.; Hayashi, N.; Voitsekhovitch, I.; Giruzzi, G.; Maget, P.; Romanelli, M.; Saarelma, S.; Stankiewitz, R.; Yoshida, M.; Zagórski, R.
2018-02-01
Reference scenarios for the JT-60SA tokamak have been simulated with one-dimensional transport codes to assess the stationary state of the flat-top phase and provide a profile database for further physics studies (e.g. MHD stability, gyrokinetic analysis) and diagnostics design. The types of scenario considered vary from pulsed standard H-mode to advanced non-inductive steady-state plasmas. In this paper we present the results obtained with the ASTRA, CRONOS, JINTRAC and TOPICS codes equipped with the Bohm/gyro-Bohm, CDBM and GLF23 transport models. The scenarios analysed here are: a standard ELMy H-mode, a hybrid scenario and a non-inductive steady state plasma, with operational parameters from the JT-60SA research plan. Several simulations of the scenarios under consideration have been performed with the above mentioned codes and transport models. The results from the different codes are in broad agreement and the main plasma parameters generally agree well with the zero dimensional estimates reported previously. The sensitivity of the results to different transport models and, in some cases, to the ELM/pedestal model has been investigated.
NASA Astrophysics Data System (ADS)
Bruehl, C.; Schallock, J.; Lelieveld, J.; Bingen, C.; Robert, C. E.; Hoepfner, M.; Clarisse, L.
2017-12-01
The atmospheric chemistry - general circulation model EMAC with a modal interactive aerosol module is used to estimate radiative effects of UTLS aerosol for the ENVISAT period 2002 to 2012 in the framework of SPARC/SSIRC. Volcanic SO2 injections by about 230 explosive volcano eruptions are estimated mostly from MIPAS limb observations. For periods of data gaps, injected SO2 is estimated indirectly from extinctions observed by GOMOS. GOMOS extinctions in the UTLS and the seasonal component of radiative forcing can be only reproduced by the model if a comprehensive treatment of desert dust and organic and black carbon is included. Upward transport of particles and gases by the Asian Monsoon appears to contribute importantly. The time series of simulated stratospheric aerosol optical depth and radiative forcing agree with the corresponding quantities derived from different satellite data sets. Comparisons of total aerosol optical depth with IASI show that tropospheric and stratospheric aerosol in the model are consistently and realistically represented.
Experimental validation of boundary element methods for noise prediction
NASA Technical Reports Server (NTRS)
Seybert, A. F.; Oswald, Fred B.
1992-01-01
Experimental validation of methods to predict radiated noise is presented. A combined finite element and boundary element model was used to predict the vibration and noise of a rectangular box excited by a mechanical shaker. The predicted noise was compared to sound power measured by the acoustic intensity method. Inaccuracies in the finite element model shifted the resonance frequencies by about 5 percent. The predicted and measured sound power levels agree within about 2.5 dB. In a second experiment, measured vibration data was used with a boundary element model to predict noise radiation from the top of an operating gearbox. The predicted and measured sound power for the gearbox agree within about 3 dB.
Uncertainty in the Future of Seasonal Snowpack over North America.
NASA Astrophysics Data System (ADS)
McCrary, R. R.; Mearns, L.
2017-12-01
The uncertainty in future changes in seasonal snowpack (snow water equivalent, SWE) and snow cover extent (SCE) for North America are explored using the North American Regional Climate Change Assessment Program (NARCCAP) suite of regional climate models (RCMs) and their driving CMIP3 global circulation models (GCMs). The higher resolution of the NARCCAP RCMs is found to add significant value to the details of future projections of SWE in topographically complex regions such as the Pacific Northwest and the Rocky Mountains. The NARCCAP models also add detailed information regarding changes in the southernmost extent of snow cover. 11 of the 12 NARCCAP ensemble members contributed SWE output which we use to explore the uncertainty in future snowpack at higher resolution. In this study, we quantify the uncertainty in future projections by looking at the spread of the interquartile range of the different models. By mid-Century the RCMs consistently predict that winter SWE amounts will decrease over most of North America. The only exception to this is in Northern Canada, where increased moisture supply leads to increases in SWE in all but one of the RCMs. While the models generally agree on the sign of the change in SWE, there is considerable spread in the magnitude (absolute and percent) of the change. The RCMs also agree that the number of days with measureable snow on the ground is projected to decrease, with snow accumulation occurring later in the Fall/Winter and melting starting earlier in the Spring/Summer. As with SWE amount, spread across the models is large for changes in the timing of the snow season and can vary by over a month between models. While most of the NARCCAP models project a total loss of measurable snow along the southernmost edge of their historical range, there is considerable uncertainty about where this will occur within the ensemble due to the bias in snow cover extent in the historical simulations. We explore methods to increase our confidence about the regions that will lose any seasonal snow.
47 CFR 13.213 - COLEM qualifications.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 1 2010-10-01 2010-10-01 false COLEM qualifications. 13.213 Section 13.213 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMERCIAL RADIO OPERATORS Examination System § 13.213... more types of commercial radio operator licenses and/or endorsements; (d) Agree to assure that, for any...
Comparison of evaporation computation methods, Pretty Lake, Lagrange County, northeastern Indiana
Ficke, John F.
1972-01-01
The different methods, although poor, agree that evaporation when there is ice cover is generally small (less than 0.1 cm day" 1 ), but the evaporation rates during the few days just before freezeup or just after ice breakup are significant
48 CFR 16.203-1 - Description.
Code of Federal Regulations, 2010 CFR
2010-10-01
... contract with economic price adjustment provides for upward and downward revision of the stated contract price upon the occurrence of specified contingencies. Economic price adjustments are of three general... decreases from an agreed-upon level in published or otherwise established prices of specific items or the...
48 CFR 16.203-1 - Description.
Code of Federal Regulations, 2011 CFR
2011-10-01
... contract with economic price adjustment provides for upward and downward revision of the stated contract price upon the occurrence of specified contingencies. Economic price adjustments are of three general... decreases from an agreed-upon level in published or otherwise established prices of specific items or the...
7 CFR 1468.7 - Participant eligibility provisions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS CONSERVATION FARM OPTION General... farm enrolling in CFO. (b) Agree to forgo earning future payments under the Conservation Reserve... compliance with the highly erodible land and wetland conservation provisions found at part 12 of this title...
Esthetic evaluation of timber harvesting in the Northern Rockies - a progressive report
Dennis L. Schweitzer; James R. Ullrich; Robert E. Benson
1976-01-01
Panels of judges have been evaluating the esthetic dimension of harvested areas in the Northern Rockies. Studies conducted in Wyoming and Montana agree with intuition in that forest scenes are generally liked less as the evidence of man's activities increases.
48 CFR 552.270-23 - Subordination, Nondisturbance and Attornment.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Subordination, Nondisturbance and Attornment. 552.270-23 Section 552.270-23 Federal Acquisition Regulations System GENERAL... this lease. Government agrees, in consideration of the warranties and conditions set forth in this...
NASA Astrophysics Data System (ADS)
Zhang, Junhua; Lohmann, Ulrike
2003-08-01
The single column model of the Canadian Centre for Climate Modeling and Analysis (CCCma) climate model is used to simulate Arctic spring cloud properties observed during the Surface Heat Budget of the Arctic Ocean (SHEBA) experiment. The model is driven by the rawinsonde observations constrained European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis data. Five cloud parameterizations, including three statistical and two explicit schemes, are compared and the sensitivity to mixed phase cloud parameterizations is studied. Using the original mixed phase cloud parameterization of the model, the statistical cloud schemes produce more cloud cover, cloud water, and precipitation than the explicit schemes and in general agree better with observations. The mixed phase cloud parameterization from ECMWF decreases the initial saturation specific humidity threshold of cloud formation. This improves the simulated cloud cover in the explicit schemes and reduces the difference between the different cloud schemes. On the other hand, because the ECMWF mixed phase cloud scheme does not consider the Bergeron-Findeisen process, less ice crystals are formed. This leads to a higher liquid water path and less precipitation than what was observed.
Validation of vibration-dissociation coupling models in hypersonic non-equilibrium separated flows
NASA Astrophysics Data System (ADS)
Shoev, G.; Oblapenko, G.; Kunova, O.; Mekhonoshina, M.; Kustova, E.
2018-03-01
The validation of recently developed models of vibration-dissociation coupling is discussed in application to numerical solutions of the Navier-Stokes equations in a two-temperature approximation for a binary N2/N flow. Vibrational-translational relaxation rates are computed using the Landau-Teller formula generalized for strongly non-equilibrium flows obtained in the framework of the Chapman-Enskog method. Dissociation rates are calculated using the modified Treanor-Marrone model taking into account the dependence of the model parameter on the vibrational state. The solutions are compared to those obtained using traditional Landau-Teller and Treanor-Marrone models, and it is shown that for high-enthalpy flows, the traditional and recently developed models can give significantly different results. The computed heat flux and pressure on the surface of a double cone are in a good agreement with experimental data available in the literature on low-enthalpy flow with strong thermal non-equilibrium. The computed heat flux on a double wedge qualitatively agrees with available data for high-enthalpy non-equilibrium flows. Different contributions to the heat flux calculated using rigorous kinetic theory methods are evaluated. Quantitative discrepancy of numerical and experimental data is discussed.
Manifold parametrization of the left ventricle for a statistical modelling of its complete anatomy
NASA Astrophysics Data System (ADS)
Gil, D.; Garcia-Barnes, J.; Hernández-Sabate, A.; Marti, E.
2010-03-01
Distortion of Left Ventricle (LV) external anatomy is related to some dysfunctions, such as hypertrophy. The architecture of myocardial fibers determines LV electromechanical activation patterns as well as mechanics. Thus, their joined modelling would allow the design of specific interventions (such as peacemaker implantation and LV remodelling) and therapies (such as resynchronization). On one hand, accurate modelling of external anatomy requires either a dense sampling or a continuous infinite dimensional approach, which requires non-Euclidean statistics. On the other hand, computation of fiber models requires statistics on Riemannian spaces. Most approaches compute separate statistical models for external anatomy and fibers architecture. In this work we propose a general mathematical framework based on differential geometry concepts for computing a statistical model including, both, external and fiber anatomy. Our framework provides a continuous approach to external anatomy supporting standard statistics. We also provide a straightforward formula for the computation of the Riemannian fiber statistics. We have applied our methodology to the computation of complete anatomical atlas of canine hearts from diffusion tensor studies. The orientation of fibers over the average external geometry agrees with the segmental description of orientations reported in the literature.
Long-time Dynamics of Stochastic Wave Breaking
NASA Astrophysics Data System (ADS)
Restrepo, J. M.; Ramirez, J. M.; Deike, L.; Melville, K.
2017-12-01
A stochastic parametrization is proposed for the dynamics of wave breaking of progressive water waves. The model is shown to agree with transport estimates, derived from the Lagrangian path of fluid parcels. These trajectories are obtained numerically and are shown to agree well with theory in the non-breaking regime. Of special interest is the impact of wave breaking on transport, momentum exchanges and energy dissipation, as well as dispersion of trajectories. The proposed model, ensemble averaged to larger time scales, is compared to ensemble averages of the numerically generated parcel dynamics, and is then used to capture energy dissipation and path dispersion.
Hoddinott, Pat; Morgan, Heather; MacLennan, Graeme; Sewel, Kate; Thomson, Gill; Bauld, Linda; Yi, Deokhee; Ludbrook, Anne; Campbell, Marion K
2014-07-18
To survey public attitudes about incentives for smoking cessation in pregnancy and for breast feeding to inform trial design. Cross-sectional survey. British general public. Seven promising incentive strategies had been identified from evidence syntheses and qualitative interview data from service users and providers. These were shopping vouchers for: (1) validated smoking cessation in pregnancy and (2) after birth; (3) for a smoke-free home; (4) for proven breast feeding; (5) a free breast pump; (6) payments to health services for reaching smoking cessation in pregnancy targets and (7) breastfeeding targets. Ipsos MORI used area quota sampling and home-administered computer-assisted questionnaires, with randomised question order to assess agreement with different incentives (measured on a five-point scale). Demographic data and target behaviour experience were recorded. Analysis used multivariable ordered logit models. Agreement with incentives was mixed (ranging from 34% to 46%) among a representative sample of 1144 British adults. Mean agreement score was highest for a free breast pump, and lowest for incentives for smoking abstinence after birth. More women disagreed with shopping vouchers than men. Those with lower levels of education disagreed more with smoking cessation incentives and a breast pump. Those aged 44 or under agreed more with all incentive strategies compared with those aged 65 and over, particularly provider targets for smoking cessation. Non-white ethnic groups agreed particularly with breastfeeding incentives. Current smokers with previous stop attempts and respondents who had breast fed children agreed with providing vouchers for the respective behaviours. Up to £40/month vouchers for behaviour change were acceptable (>85%). Women and the less educated were more likely to disagree, but men and women of childbearing age to agree, with incentives designed for their benefit. Trials evaluating reach, impact on health inequalities and ethnic groups are required prior to implementing incentive interventions. CRD42012001980. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Krok-Schoen, Jessica L; Bernardo, Brittany M; Weier, Rory C; Peng, Juan; Katz, Mira L; Reiter, Paul L; Richardson, Morgan S; Pennell, Michael L; Tatum, Cathy M; Paskett, Electra D
2017-11-14
To examine how demographic, general health, religious, and political characteristics influenced beliefs about mandatory school vaccinations and history of vaccination refusal for children among Ohio Appalachian parents. In 2013 and 2014, baseline data were obtained from parents (n = 337) of girls aged 9-17 from 12 counties in rural Ohio Appalachia enrolled in the Community Awareness, Resources and Education (CARE II) Project. Multivariate logistic regression models were used to identify correlates of parental beliefs about mandatory school vaccinations and history of refusing a doctor-recommended vaccine for their child(ren). About 47% of parents agreed that parents should have the right to refuse mandatory school vaccinations for their child(ren). Participants who reported their political affiliation as Republican (OR = 2.45, 95% CI: 1.28-4.66) or Independent (OR = 3.31, 95% CI: 1.70-6.44) were more likely to agree that parents should have the right to refuse school-mandated vaccinations than parents who reported their political affiliation as Democrat. Approximately 39% of parents reported ever refusing a vaccine for their child(ren). Participants who were female (OR = 3.90, 95% CI: 1.04-14.58) and believed that parents should have the right to refuse mandatory school vaccinations (OR = 3.27, 95% CI: 1.90-5.62) were more likely to report ever refusing a vaccine for their child(ren). The study findings provide information to better understand factors related to vaccination refusal among parents in Appalachia Ohio that can be used to design interventions to improve vaccination uptake. © 2017 National Rural Health Association.
Golombek, S G; Sola, A; Baquero, H; Borbonet, D; Cabañas, F; Fajardo, C; Goldsmit, G; Lemus, L; Miura, E; Pellicer, A; Pérez, J M; Rogido, M; Zambosco, G; van Overmeire, B
2008-11-01
To report the process and results of the first neonatal clinical consensus of the Ibero-American region. Two recognized experts in the field (Clyman and Van Overmeire) and 45 neonatologists from 23 countries were invited for active participation and collaboration. We developed 46 questions of clinical-physiological relevance in all aspects of patent ductus arteriosus (PDA). Guidelines for consensus process, literature search and future preparation of educational material and authorship were developed, reviewed and agreed by all. Participants from different countries were distributed in groups, and assigned to interact and work together to answer 3-5 questions, reviewing all global literature and local factors. Answers and summaries were received, collated and reviewed by 2 coordinators and the 2 experts. Participants and experts met in Granada, Spain for 4.5 h (lectures by experts, presentations by groups, discussion, all literature available). 31 neonatologists from 16 countries agreed to participate. Presentations by each group and general discussion were used to develop a consensus regarding: general management, availability of drugs (indomethacin vs. ibuprofen), costs, indications for echo/surgery, etc. Many steps were learnt by all present in a collaborative forum. This first consensus group of Ibero-American neonatologists SIBEN led to active and collaborative participation of neonatologists of 16 countries, improved education of all participants and ended with consensus development on clinical approaches to PDA. Furthermore, it provides recommendations for clinical care reached by consensus. Additionally, it will serve as a useful foundation for future SIBEN Consensus on other topics and it could become valuable as a model to decrease disparity in care and improve outcomes in this and other regions.
NASA Astrophysics Data System (ADS)
Li, Xiaoyu; Fan, Guodong; Pan, Ke; Wei, Guo; Zhu, Chunbo; Rizzoni, Giorgio; Canova, Marcello
2017-11-01
The design of a lumped parameter battery model preserving physical meaning is especially desired by the automotive researchers and engineers due to the strong demand for battery system control, estimation, diagnosis and prognostics. In light of this, a novel simplified fractional order electrochemical model is developed for electric vehicle (EV) applications in this paper. In the model, a general fractional order transfer function is designed for the solid phase lithium ion diffusion approximation. The dynamic characteristics of the electrolyte concentration overpotential are approximated by a first-order resistance-capacitor transfer function in the electrolyte phase. The Ohmic resistances and electrochemical reaction kinetics resistance are simplified to a lumped Ohmic resistance parameter. Overall, the number of model parameters is reduced from 30 to 9, yet the accuracy of the model is still guaranteed. In order to address the dynamics of phase-change phenomenon in the active particle during charging and discharging, variable solid-state diffusivity is taken into consideration in the model. Also, the observability of the model is analyzed on two types of lithium ion batteries subsequently. Results show the fractional order model with variable solid-state diffusivity agrees very well with experimental data at various current input conditions and is suitable for electric vehicle applications.
Projecting shifts in thermal habitat for 686 species on the North American continental shelf
Selden, Rebecca L.; Latour, Robert J.; Frölicher, Thomas L.; Seagraves, Richard J.; Pinsky, Malin L.
2018-01-01
Recent shifts in the geographic distribution of marine species have been linked to shifts in preferred thermal habitats. These shifts in distribution have already posed challenges for living marine resource management, and there is a strong need for projections of how species might be impacted by future changes in ocean temperatures during the 21st century. We modeled thermal habitat for 686 marine species in the Atlantic and Pacific oceans using long-term ecological survey data from the North American continental shelves. These habitat models were coupled to output from sixteen general circulation models that were run under high (RCP 8.5) and low (RCP 2.6) future greenhouse gas emission scenarios over the 21st century to produce 32 possible future outcomes for each species. The models generally agreed on the magnitude and direction of future shifts for some species (448 or 429 under RCP 8.5 and RCP 2.6, respectively), but strongly disagreed for other species (116 or 120 respectively). This allowed us to identify species with more or less robust predictions. Future shifts in species distributions were generally poleward and followed the coastline, but also varied among regions and species. Species from the U.S. and Canadian west coast including the Gulf of Alaska had the highest projected magnitude shifts in distribution, and many species shifted more than 1000 km under the high greenhouse gas emissions scenario. Following a strong mitigation scenario consistent with the Paris Agreement would likely produce substantially smaller shifts and less disruption to marine management efforts. Our projections offer an important tool for identifying species, fisheries, and management efforts that are particularly vulnerable to climate change impacts. PMID:29768423
Rio, Ines M; McNally, Orla
2017-10-01
Endometrial cancer is the most common invasive gynaecological cancer in Australia. Despite the fact that review after treatment of early endometrial cancer has not been shown to detect recurrent disease, practice at several hospitals brings women back for specialist hospital review for 5 years after definitive cancer surgery. Implement an improved model of follow-up care following hospital treatment for early endometrial cancer. Quantitative and qualitative. Seventy-three of the eligible 81 women undertook the model of care. All general practitioners (GPs) agreed to follow-up care. Thirty-one women (42%) and 37 GPs (51%) returned surveys. All women found the nurse consultation very useful or useful with 77% reporting making lifestyle changes and 87% found the GP consultation very useful or useful with 72% reporting making lifestyle changes. Eighty-nine percent of GPs found the care plan useful, 94% set up patient recall systems, 79% used the care plan to develop their own care plan, 100% felt confident in providing follow-up care with 91% reporting the care plan and hospital processes improved their confidence. Comparison with the pre-cohort women showed: higher rates of communication at various care points to GPs (from P < 0.001); more referrals (P < 0.001); and a projected decrease of nine hospital doctor appointments per patient. With an increasing number of people surviving cancer, in order to address holistic health needs and maintain tertiary service capacity, general practice will be required to provide more follow-up care. Our model demonstrates an acceptable and quality mechanism for this to occur. © 2017 Commonwealth of Australia. Australian and New Zealand Journal of Obstetrics and Gynaecology © 2017 Royal Australian and New Zealand College of Obstetricians and Gynaecologists.
Projecting shifts in thermal habitat for 686 species on the North American continental shelf.
Morley, James W; Selden, Rebecca L; Latour, Robert J; Frölicher, Thomas L; Seagraves, Richard J; Pinsky, Malin L
2018-01-01
Recent shifts in the geographic distribution of marine species have been linked to shifts in preferred thermal habitats. These shifts in distribution have already posed challenges for living marine resource management, and there is a strong need for projections of how species might be impacted by future changes in ocean temperatures during the 21st century. We modeled thermal habitat for 686 marine species in the Atlantic and Pacific oceans using long-term ecological survey data from the North American continental shelves. These habitat models were coupled to output from sixteen general circulation models that were run under high (RCP 8.5) and low (RCP 2.6) future greenhouse gas emission scenarios over the 21st century to produce 32 possible future outcomes for each species. The models generally agreed on the magnitude and direction of future shifts for some species (448 or 429 under RCP 8.5 and RCP 2.6, respectively), but strongly disagreed for other species (116 or 120 respectively). This allowed us to identify species with more or less robust predictions. Future shifts in species distributions were generally poleward and followed the coastline, but also varied among regions and species. Species from the U.S. and Canadian west coast including the Gulf of Alaska had the highest projected magnitude shifts in distribution, and many species shifted more than 1000 km under the high greenhouse gas emissions scenario. Following a strong mitigation scenario consistent with the Paris Agreement would likely produce substantially smaller shifts and less disruption to marine management efforts. Our projections offer an important tool for identifying species, fisheries, and management efforts that are particularly vulnerable to climate change impacts.
NASA Astrophysics Data System (ADS)
Clayton, J. D.
2017-02-01
A theory of deformation of continuous media based on concepts from Finsler differential geometry is presented. The general theory accounts for finite deformations, nonlinear elasticity, and changes in internal state of the material, the latter represented by elements of a state vector of generalized Finsler space whose entries consist of one or more order parameter(s). Two descriptive representations of the deformation gradient are considered. The first invokes an additive decomposition and is applied to problems involving localized inelastic deformation mechanisms such as fracture. The second invokes a multiplicative decomposition and is applied to problems involving distributed deformation mechanisms such as phase transformations or twinning. Appropriate free energy functions are posited for each case, and Euler-Lagrange equations of equilibrium are derived. Solutions are obtained for specific problems of tensile fracture of an elastic cylinder and for amorphization of a crystal under spherical and uniaxial compression. The Finsler-based approach is demonstrated to be more general and potentially more physically descriptive than existing hyperelasticity models couched in Riemannian geometry or Euclidean space, without incorporation of supplementary ad hoc equations or spurious fitting parameters. Predictions for single crystals of boron carbide ceramic agree qualitatively, and in many instances quantitatively, with results from physical experiments and atomic simulations involving structural collapse and failure of the crystal along its c-axis.
Friend, Andrew D; Lucht, Wolfgang; Rademacher, Tim T; Keribin, Rozenn; Betts, Richard; Cadule, Patricia; Ciais, Philippe; Clark, Douglas B; Dankers, Rutger; Falloon, Pete D; Ito, Akihiko; Kahana, Ron; Kleidon, Axel; Lomas, Mark R; Nishina, Kazuya; Ostberg, Sebastian; Pavlick, Ryan; Peylin, Philippe; Schaphoff, Sibyll; Vuichard, Nicolas; Warszawski, Lila; Wiltshire, Andy; Woodward, F Ian
2014-03-04
Future climate change and increasing atmospheric CO2 are expected to cause major changes in vegetation structure and function over large fractions of the global land surface. Seven global vegetation models are used to analyze possible responses to future climate simulated by a range of general circulation models run under all four representative concentration pathway scenarios of changing concentrations of greenhouse gases. All 110 simulations predict an increase in global vegetation carbon to 2100, but with substantial variation between vegetation models. For example, at 4 °C of global land surface warming (510-758 ppm of CO2), vegetation carbon increases by 52-477 Pg C (224 Pg C mean), mainly due to CO2 fertilization of photosynthesis. Simulations agree on large regional increases across much of the boreal forest, western Amazonia, central Africa, western China, and southeast Asia, with reductions across southwestern North America, central South America, southern Mediterranean areas, southwestern Africa, and southwestern Australia. Four vegetation models display discontinuities across 4 °C of warming, indicating global thresholds in the balance of positive and negative influences on productivity and biomass. In contrast to previous global vegetation model studies, we emphasize the importance of uncertainties in projected changes in carbon residence times. We find, when all seven models are considered for one representative concentration pathway × general circulation model combination, such uncertainties explain 30% more variation in modeled vegetation carbon change than responses of net primary productivity alone, increasing to 151% for non-HYBRID4 models. A change in research priorities away from production and toward structural dynamics and demographic processes is recommended.
Friend, Andrew D.; Lucht, Wolfgang; Rademacher, Tim T.; Keribin, Rozenn; Betts, Richard; Cadule, Patricia; Ciais, Philippe; Clark, Douglas B.; Dankers, Rutger; Falloon, Pete D.; Ito, Akihiko; Kahana, Ron; Kleidon, Axel; Lomas, Mark R.; Nishina, Kazuya; Ostberg, Sebastian; Pavlick, Ryan; Peylin, Philippe; Schaphoff, Sibyll; Vuichard, Nicolas; Warszawski, Lila; Wiltshire, Andy; Woodward, F. Ian
2014-01-01
Future climate change and increasing atmospheric CO2 are expected to cause major changes in vegetation structure and function over large fractions of the global land surface. Seven global vegetation models are used to analyze possible responses to future climate simulated by a range of general circulation models run under all four representative concentration pathway scenarios of changing concentrations of greenhouse gases. All 110 simulations predict an increase in global vegetation carbon to 2100, but with substantial variation between vegetation models. For example, at 4 °C of global land surface warming (510–758 ppm of CO2), vegetation carbon increases by 52–477 Pg C (224 Pg C mean), mainly due to CO2 fertilization of photosynthesis. Simulations agree on large regional increases across much of the boreal forest, western Amazonia, central Africa, western China, and southeast Asia, with reductions across southwestern North America, central South America, southern Mediterranean areas, southwestern Africa, and southwestern Australia. Four vegetation models display discontinuities across 4 °C of warming, indicating global thresholds in the balance of positive and negative influences on productivity and biomass. In contrast to previous global vegetation model studies, we emphasize the importance of uncertainties in projected changes in carbon residence times. We find, when all seven models are considered for one representative concentration pathway × general circulation model combination, such uncertainties explain 30% more variation in modeled vegetation carbon change than responses of net primary productivity alone, increasing to 151% for non-HYBRID4 models. A change in research priorities away from production and toward structural dynamics and demographic processes is recommended. PMID:24344265
An analytical approach to obtaining JWL parameters from cylinder tests
NASA Astrophysics Data System (ADS)
Sutton, B. D.; Ferguson, J. W.; Hodgson, A. N.
2017-01-01
An analytical method for determining parameters for the JWL Equation of State from cylinder test data is described. This method is applied to four datasets obtained from two 20.3 mm diameter EDC37 cylinder tests. The calculated pressure-relative volume (p-Vr) curves agree with those produced by hydro-code modelling. The average calculated Chapman-Jouguet (CJ) pressure is 38.6 GPa, compared to the model value of 38.3 GPa; the CJ relative volume is 0.729 for both. The analytical pressure-relative volume curves produced agree with the one used in the model out to the commonly reported expansion of 7 relative volumes, as do the predicted energies generated by integrating under the p-Vr curve. The calculated energy is within 1.6% of that predicted by the model.
Relativistic Outflows from ADAFs
NASA Astrophysics Data System (ADS)
Becker, Peter; Subramanian, Prasad; Kazanas, Demosthenes
2001-04-01
Advection-dominated accretion flows (ADAFs) have a positive Bernoulli parameter, and are therefore gravitationally bound. The Newtonian ADAF model has been generalized recently to obtain the ADIOS model that includes outflows of energy and angular momentum, thereby allowing accretion to proceed self-consistently. However, the utilization of a Newtonian gravitational potential limits the ability of this model to describe the inner region of the disk, where any relativistic outflows are likely to originate. In this paper we modify the ADIOS scenario to incorporate a seudo - Newtonian potential, which approximates the effects of general relativity. The analysis yields a unique, self - similar solution for the structure of the coupled disk/wind system. Interesting features of the new solution include the relativistic character of the outflow in the vicinity of the radius of marginal stability, which represents the inner edge of the quasi-Keplerian disk in our model. Our self - similar model may therefore help to explain the origin of relativistic jets in active galaxies. At large distances the radial dependence of the accretion rate approachs the unique form dot M ∝ r^1/2, with an associated density variation given by ρ ∝ r-1. This density variation agrees with that implied by the dependence of the X-ray hard time lags on the Fourier frequency for a number of accreting galactic black hole candidates. While intriguing, the results of our self-similar model need to be confirmed in the future by incorporating a detailed physical description of the energization mechanism that drives the outflow, which is likely to be powered by the shear of the underlying accretion disk.
The use of screening effects in modelling route-based daytime road surface temperature
NASA Astrophysics Data System (ADS)
Hu, Yumei; Almkvist, Esben; Lindberg, Fredrik; Bogren, Jörgen; Gustavsson, Torbjörn
2016-07-01
Winter road maintenance is essential for road safety. Accurate predictions of the road surface temperature (RST) and conditions can enhance the efficiency of winter road maintenance. Screening effects, which encompass shading effects and the influence of the sky-view factor ( ψ s ), influence RST distributions because they affect road surface radiation fluxes. In this work, light detection and ranging (Lidar) data are used to derive shadow patterns and ψ s values, and the resulting shadow patterns are used to model route-based RST distributions along two stretches of road in Sweden. The shading patterns and road surface radiation fluxes calculated from the Lidar data generally agreed well with measured RST values. Variation in land use types and the angle between the road direction and solar azimuth may introduce uncertainties, and accounting for these factors may improve the results obtained in certain cases. A simple shading model that only accounts for the direct radiation at the instant of measurement is often sufficient to provide reasonably accurate RST estimates. However, in certain cases, such as those involving measurements close to sunset, it is important to consider the radiation accumulated over several hours. The inclusion of ψ s improves the model performance even more in such cases. Overall, RST models based on the accumulated direct shortwave radiation offered an optimal balance of simplicity and accuracy. General radiation models were built for country road and highway environments, explaining up to 70 and 65 %, respectively, of the observed variation in RST along the corresponding stretches of road.
Petersson, Kristoffer; Jaccard, Maud; Germond, Jean-François; Buchillier, Thierry; Bochud, François; Bourhis, Jean; Vozenin, Marie-Catherine; Bailat, Claude
2017-03-01
The purpose of this work was to establish an empirical model of the ion recombination in the Advanced Markus ionization chamber for measurements in high dose rate/dose-per-pulse electron beams. In addition, we compared the observed ion recombination to calculations using the standard Boag two-voltage-analysis method, the more general theoretical Boag models, and the semiempirical general equation presented by Burns and McEwen. Two independent methods were used to investigate the ion recombination: (a) Varying the grid tension of the linear accelerator (linac) gun (controls the linac output) and measuring the relative effect the grid tension has on the chamber response at different source-to-surface distances (SSD). (b) Performing simultaneous dose measurements and comparing the dose-response, in beams with varying dose rate/dose-per-pulse, with the chamber together with dose rate/dose-per-pulse independent Gafchromic™ EBT3 film. Three individual Advanced Markus chambers were used for the measurements with both methods. All measurements were performed in electron beams with varying mean dose rate, dose rate within pulse, and dose-per-pulse (10 -2 ≤ mean dose rate ≤ 10 3 Gy/s, 10 2 ≤ mean dose rate within pulse ≤ 10 7 Gy/s, 10 -4 ≤ dose-per-pulse ≤ 10 1 Gy), which was achieved by independently varying the linac gun grid tension, and the SSD. The results demonstrate how the ion collection efficiency of the chamber decreased as the dose-per-pulse increased, and that the ion recombination was dependent on the dose-per-pulse rather than the dose rate, a behavior predicted by Boag theory. The general theoretical Boag models agreed well with the data over the entire investigated dose-per-pulse range, but only for a low polarizing chamber voltage (50 V). However, the two-voltage-analysis method and the Burns & McEwen equation only agreed with the data at low dose-per-pulse values (≤ 10 -2 and ≤ 10 -1 Gy, respectively). An empirical model of the ion recombination in the chamber was found by fitting a logistic function to the data. The ion collection efficiency of the Advanced Markus ionization chamber decreases for measurements in electron beams with increasingly higher dose-per-pulse. However, this chamber is still functional for dose measurements in beams with dose-per-pulse values up toward and above 10 Gy, if the ion recombination is taken into account. Our results show that existing models give a less-than-accurate description of the observed ion recombination. This motivates the use of the presented empirical model for measurements with the Advanced Markus chamber in high dose-per-pulse electron beams, as it enables accurate absorbed dose measurements (uncertainty estimation: 2.8-4.0%, k = 1). The model depends on the dose-per-pulse in the beam, and it is also influenced by the polarizing chamber voltage, with increasing ion recombination with a lowering of the voltage. © 2017 American Association of Physicists in Medicine.
Milsom, K; Tickle, M; Jenner, A; Moulding, G
1999-01-09
To clarify the function of the school based dental inspection. For representatives of the Community Dental Service, General Dental Service and Hospital Dental Service to identify an agreed set of criteria for the referral of children following school dental inspection. Qualitative research methodology used to establish a consensus for the inclusion of referral criteria following dental screening. Ellesmere Port, Cheshire, England. A Delphi technique was used to establish a consensus amongst the study participants on the inclusion of nine possible criteria for referral following dental screening. All participants scored each criterion in the range 1-9, with a score of 1 indicating that referral of individuals with the condition should definitely not take place, and a score of 9 indicating referral should definitely take place. Referral criteria were accepted only if they achieved a group median score of 7 or more, with an interquartile range of three scale points, with the lower value being no less than 7. Four of the nine possible criteria met the agreed group standard for inclusion: 'Sepsis', 'Caries in the secondary dentition', 'Overjet > 10 mm', and 'Registered & caries in the permanent dentition'. It is possible to agree clear criteria for the referral of children following the school dental inspection.
Code of Federal Regulations, 2010 CFR
2010-07-01
... Secretary of Labor LABOR STANDARDS FOR FEDERAL SERVICE CONTRACTS Application of the McNamara-O'Hara Service Contract Act Covered Contracts Generally § 4.114 Subcontracts. (a) “Contractor” as including “subcontractor... contractor undertakes a contract subject to the Act, the contractor agrees to assume the obligation that the...
Code of Federal Regulations, 2010 CFR
2010-10-01
... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Examples. 9.508 Section 9... CONTRACTOR QUALIFICATIONS Organizational and Consultant Conflicts of Interest 9.508 Examples. The examples in... officer apply the general rules in 9.505 to individual contract situations. (a) Company A agrees to...
7 CFR 1425.17 - Eligible commodity and pooling.
Code of Federal Regulations, 2010 CFR
2010-01-01
... to generally accepted accounting principles. (l) A CMA shall not apply marketing losses from a..., DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS COOPERATIVE MARKETING ASSOCIATIONS § 1425.17... marketing proceeds from the commodity in accordance with § 1425.18; and (5) Members agreed to accept a...
7 CFR 1710.114 - TIER, DSC, OTIER and ODSC requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
...) General. Requirements for coverage ratios are set forth in the borrower's mortgage, loan contract, or..., shall reduce the coverage ratio requirements of a borrower that has contractually agreed with RUS to a higher requirement. (b) Coverage ratios. (1) Distribution borrowers. The minimum coverage ratios required...
Philosophy of Education and Other Educational Sciences
ERIC Educational Resources Information Center
Howe, Kenneth R.
2014-01-01
This article largely agrees with John White's characterizations of the relationships among philosophy of education, philosophy more generally, and the conventional world. It then extends what White identifies as the fundamental problem that should now be occupying philosophy of education--the irreconcilable opposition between education for…
Clerkin, P; Buckley, B S; Murphy, A W; MacFarlane, A E
2013-02-01
National policies are being developed, which may limit access to patients' records for health research. This could reduce the ability of health research to benefit society as a whole. It is important to develop an in-depth understanding of people's views across demographic groups to inform such policy development. Aims. To explore patients' views about the use of their general practice records in health research with attention to gender and age. Design of study. Qualitative study using focus groups. Six General Practices in the west of Ireland. Focus Group interviews with 35 people who were patients at the practices. Overall, participants were positively inclined towards the idea of information from their records (anonymous and identifiable) being used in research for the 'greater good' although there were some concerns about personal information being 'leaked'. Males emphasized risks in relation to employment and finances, whereas females emphasized risks in relation to social discomfort and embarrassment. Participants were supportive of consent models that enable patients to give prior ongoing consent for specific agreed 'levels' of data use, affording patients self-determination without the need for consent request on study-by-study basis. Overall male and female patients of different ages are supportive of the use of their general practice records in health research and of general practitioners as data protectors.
Generalized Sagdeev potential theory for shock waves modeling
NASA Astrophysics Data System (ADS)
Akbari-Moghanjoughi, M.
2017-05-01
In this paper, we develop an innovative approach to study the shock wave propagation using the Sagdeev potential method. We also present an analytical solution for Korteweg de Vries Burgers (KdVB) and modified KdVB equation families with a generalized form of the nonlinearity term which agrees well with the numerical one. The novelty of the current approach is that it is based on a simple analogy of the particle in a classical potential with the variable particle energy providing one with a deeper physical insight into the problem and can easily be extended to more complex physical situations. We find that the current method well describes both monotonic and oscillatory natures of the dispersive-diffusive shock structures in different viscous fluid configurations. It is particularly important that all essential parameters of the shock structure can be deduced directly from the Sagdeev potential in small and large potential approximation regimes. Using the new method, we find that supercnoidal waves can decay into either compressive or rarefactive shock waves depending on the initial wave amplitude. Current investigation provides a general platform to study a wide range of phenomena related to nonlinear wave damping and interactions in diverse fluids including plasmas.
NASA Astrophysics Data System (ADS)
Pastor, M. A.; Casado, M. J.
2012-10-01
This paper presents an evaluation of the multi-model simulations for the 4th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) in terms of their ability to simulate the ERA40 circulation types over the Euro-Atlantic region in winter season. Two classification schemes, k-means and SANDRA, have been considered to test the sensitivity of the evaluation results to the classification procedure. The assessment allows establishing different rankings attending spatial and temporal features of the circulation types. Regarding temporal characteristics, in general, all AR4 models tend to underestimate the frequency of occurrence. The best model simulating spatial characteristics is the UKMO-HadGEM1 whereas CCSM3, UKMO-HadGEM1 and CGCM3.1(T63) are the best simulating the temporal features, for both classification schemes. This result agrees with the AR4 models ranking obtained when having analysed the ability of the same AR4 models to simulate Euro-Atlantic variability modes. This study has proved the utility of applying such a synoptic climatology approach as a diagnostic tool for models' assessment. The ability of the models to properly reproduce the position of ridges and troughs and the frequency of synoptic patterns, will therefore improve our confidence in the response of models to future climate changes.
Kumar, Amit; Chauhan, R P; Joshi, Manish; Sahoo, B K
2014-01-01
Building materials are the second major source of indoor radon after soil. The contribution of building materials towards indoor radon depends upon the radium content and exhalation rates and can be used as a primary index for radon levels in the dwellings. The radon flux data from the building materials was used for calculation of the indoor radon concentrations and doses by many researchers using one and two dimensional model suggested by various researchers. In addition to radium content, the radon wall flux from a surface strongly depends upon the radon diffusion length (L) and thickness of the wall (2d). In the present work the indoor radon concentrations from the measured radon exhalation rate of building materials calculated using different models available in literature and validation of models was made through measurement. The variation in the predicted radon flux from different models was compared with d/L value for wall and roofs of different dwellings. The results showed that the radon concentrations predicted by models agree with experimental value. The applicability of different model with d/L ratio was discussed. The work aims to select a more appropriate and general model among available models in literature for the prediction of indoor radon. Copyright © 2013 Elsevier Ltd. All rights reserved.
Interpretation of pH-activity profiles for acid-base catalysis from molecular simulations.
Dissanayake, Thakshila; Swails, Jason M; Harris, Michael E; Roitberg, Adrian E; York, Darrin M
2015-02-17
The measurement of reaction rate as a function of pH provides essential information about mechanism. These rates are sensitive to the pK(a) values of amino acids directly involved in catalysis that are often shifted by the enzyme active site environment. Experimentally observed pH-rate profiles are usually interpreted using simple kinetic models that allow estimation of "apparent pK(a)" values of presumed general acid and base catalysts. One of the underlying assumptions in these models is that the protonation states are uncorrelated. In this work, we introduce the use of constant pH molecular dynamics simulations in explicit solvent (CpHMD) with replica exchange in the pH-dimension (pH-REMD) as a tool to aid in the interpretation of pH-activity data of enzymes and to test the validity of different kinetic models. We apply the methods to RNase A, a prototype acid-base catalyst, to predict the macroscopic and microscopic pK(a) values, as well as the shape of the pH-rate profile. Results for apo and cCMP-bound RNase A agree well with available experimental data and suggest that deprotonation of the general acid and protonation of the general base are not strongly coupled in transphosphorylation and hydrolysis steps. Stronger coupling, however, is predicted for the Lys41 and His119 protonation states in apo RNase A, leading to the requirement for a microscopic kinetic model. This type of analysis may be important for other catalytic systems where the active forms of the implicated general acid and base are oppositely charged and more highly correlated. These results suggest a new way for CpHMD/pH-REMD simulations to bridge the gap with experiments to provide a molecular-level interpretation of pH-activity data in studies of enzyme mechanisms.
Interpretation of pH-activity Profiles for Acid-Base Catalysis from Molecular Simulations
Dissanayake, Thakshila; Swails, Jason; Harris, Michael E.; Roitberg, Adrian E.; York, Darrin M.
2015-01-01
The measurement of reaction rate as a function of pH provides essential information about mechanism. These rates are sensitive to the pKa values of amino acids directly involved in catalysis that are often shifted by the enzyme active site environment. Experimentally observed pH-rate profiles are usually interpreted using simple kinetic models that allow estimation of “apparent pKa” values of presumed general acid and base catalysts. One of the underlying assumptions in these models is that the protonation states are uncorrelated. In the present work, we introduce the use of constant pH molecular dynamics simulations in explicit solvent (CpHMD) with replica exchange in the pH-dimension (pH-REMD) as a tool to aid in the interpretation of pH-activity data of enzymes, and test the validity of different kinetic models. We apply the methods to RNase A, a prototype acid/base catalyst, to predict the macroscopic and microscopic pKa values, as well as the shape of the pH-rate profile. Results for apo and cCMP-bound RNase A agree well with available experimental data, and suggest that deprotonation of the general acid and protonation of the general base are not strongly coupled in transphosphorylation and hydrolysis steps. Stronger coupling, however, is predicted for the Lys41 and His119 protonation states in apo RNase A, leading to the requirement for a microscopic kinetic model. This type of analysis may be important for other catalytic systems where the active forms of implicated general acid and base are oppositely charged and more highly correlated. These results suggest a new way for CpHMD/pH-REMD simulations to bridge the gap with experiments to provide a molecular-level interpretation of pH-activity data in studies of enzyme mechanisms. PMID:25615525
Chen, Hung-Cheng; Hsu, Chao-Ping
2005-12-29
To calculate electronic couplings for photoinduced electron transfer (ET) reactions, we propose and test the use of ab initio quantum chemistry calculation for excited states with the generalized Mulliken-Hush (GMH) method. Configuration-interaction singles (CIS) is proposed to model the locally excited (LE) and charge-transfer (CT) states. When the CT state couples with other high lying LE states, affecting coupling values, the image charge approximation (ICA), as a simple solvent model, can lower the energy of the CT state and decouple the undesired high-lying local excitations. We found that coupling strength is weakly dependent on many details of the solvent model, indicating the validity of the Condon approximation. Therefore, a trustworthy value can be obtained via this CIS-GMH scheme, with ICA used as a tool to improve and monitor the quality of the results. Systems we tested included a series of rigid, sigma-linked donor-bridge-acceptor compounds where "through-bond" coupling has been previously investigated, and a pair of molecules where "through-space" coupling was experimentally demonstrated. The calculated results agree well with experimentally inferred values in the coupling magnitudes (for both systems studied) and in the exponential distance dependence (for the through-bond series). Our results indicate that this new scheme can properly account for ET coupling arising from both through-bond and through-space mechanisms.
General relativistic razor-thin disks with magnetically polarized matter
NASA Astrophysics Data System (ADS)
Navarro-Noguera, Anamaría; Lora-Clavijo, F. D.; González, Guillermo A.
2018-06-01
The origin of magnetic fields in the universe still remains unknown and constitutes one of the most intriguing questions in astronomy and astrophysics. Their significance is enormous since they have a strong influence on many astrophysical phenomena. In regards of this motivation, theoretical models of galactic disks with sources of magnetic field may contribute to understand the physics behind them. Inspired by this, we present a new family of analytical models for thin disks composed by magnetized material. The solutions are axially symmetric, conformastatic and are obtained by solving the Einstein-Maxwell Field Equations for continuum media without the test field approximation, and assuming that the sources are razor-thin disk of magnetically polarized matter. We find analytical expressions for the surface energy density, the pressure, the polarization vector, the electromagnetic fields, the mass and the rotational velocity for circular orbits, for two particular solutions. In each case, the energy-momentum tensor agrees with the energy conditions and also the convergence of the mass for all the solutions is proved. Since the solutions are well-behaved, they may be used to model astrophysical thin disks, and also may contribute as initial data in numerical simulations. In addition, the process to obtain the solutions is described in detail, which may be used as a guide to find solutions with magnetized material in General Relativity.
Topological structures in the equities market network
Leibon, Gregory; Pauls, Scott; Rockmore, Daniel; Savell, Robert
2008-01-01
We present a new method for articulating scale-dependent topological descriptions of the network structure inherent in many complex systems. The technique is based on “partition decoupled null models,” a new class of null models that incorporate the interaction of clustered partitions into a random model and generalize the Gaussian ensemble. As an application, we analyze a correlation matrix derived from 4 years of close prices of equities in the New York Stock Exchange (NYSE) and National Association of Securities Dealers Automated Quotation (NASDAQ). In this example, we expose (i) a natural structure composed of 2 interacting partitions of the market that both agrees with and generalizes standard notions of scale (e.g., sector and industry) and (ii) structure in the first partition that is a topological manifestation of a well-known pattern of capital flow called “sector rotation.” Our approach gives rise to a natural form of multiresolution analysis of the underlying time series that naturally decomposes the basic data in terms of the effects of the different scales at which it clusters. We support our conclusions and show the robustness of the technique with a successful analysis on a simulated network with an embedded topological structure. The equities market is a prototypical complex system, and we expect that our approach will be of use in understanding a broad class of complex systems in which correlation structures are resident.
1988-06-01
General Outpatient Clinic Patient Appointment System c. The survey was reviewed by FAMC’s Chief of Biostatistics to ensure content validity. 3. Approval of...efficient solution. Certain characteristics of the Fitzsimons General Outpatient Clinic made it ideal for conversion. In proportion to the low number of...OUTPATIENT CLINIC . [] Agree [] Disagree CENTRALIZED APPOINTMENT SYSTEM 6. BETWEEN 18 MAY AND 30 NOVEMBER 1987 APPOINTMENTS WERE MADE THROUGH THE
NASA Astrophysics Data System (ADS)
Verstappen, J.; Fritz, J.; Baes, M.; Smith, M. W. L.; Allaert, F.; Bianchi, S.; Blommaert, J. A. D. L.; De Geyter, G.; De Looze, I.; Gentile, G.; Gordon, K. D.; Holwerda, B. W.; Viaene, S.; Xilouris, E. M.
2013-08-01
Context. Edge-on spiral galaxies with prominent dust lanes provide us with an excellent opportunity to study the distribution and properties of the dust within them. The HEROES project was set up to observe a sample of seven large edge-on galaxies across various wavelengths for this investigation. Aims: Within this first paper, we present the Herschel observations and perform a qualitative and quantitative analysis on them, and we derive some global properties of the far infrared and submillimetre emission. Methods: We determine horizontal and vertical profiles from the Herschel observations of the galaxies in the sample and describe the morphology. Modified black-body fits to the global fluxes, measured using aperture photometry, result in dust temperatures and dust masses. The latter values are compared to those that are derived from radiative transfer models taken from the literature. Results: On the whole, our Herschel flux measurements agree well with archival values. We find that the exponential horizontal dust distribution model often used in the literature generally provides a good description of the observed horizontal profiles. Three out of the seven galaxies show signatures of extended vertical emission at 100 and 160 μm at the 5σ level, but in two of these it is probably due to deviations from an exactly edge-on orientation. Only for NGC 4013, a galaxy in which vertically extended dust has already been detected in optical images, we can detect vertically extended dust, and the derived scaleheight agrees with the value estimated through radiative transfer modelling. Our analysis hints at a correlation between the dust scaleheight and its degree of clumpiness, which we infer from the difference between the dust masses as calculated from modelling of optical data and from fitting the spectral energy distribution of Herschel datapoints. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.
Intra-seasonal Oscillations Inferred from SABER (TIMED) and MLS (UARS) Temperature Measurements
NASA Technical Reports Server (NTRS)
Huang, F. T.; Mayr, H. G.; Russell, J.; Mlynczak, M.; Reber, C. A.; Mengel, J. G.
2006-01-01
In the zonal mean meridional winds of the upper mesosphere, intra-seasonal oscillations with periods between 1 and 4 months have been inferred from UARS measurements and independently predicted with the Numerical Spectral Model WSM). The wind oscillations tend to be confined to low latitudes and appear to be driven, at least in part, by small-scale gravity waves propagating in the meridional direction. Winds across the equator should generate, due to dynamical heating and cooling, temperature oscillations with opposite phase in the two hemispheres. Investigating this phenomenon, we have analyzed SABER temperatures from TIMED in the altitude range between 55 and 95 km to delineate with an empirical model, the year-long variability of the migrating tides and zonal mean components. The inferred seasonal variations of the diurnal tide, characterized by amplitude maxima near equinox, are in substantial agreement with UARS observations and results from the NSM. For the zonal mean, the dominant seasonal variations in the SABER temperatures, with annual (12 months) and semiannual (6 months) periodicities, agree well with those derived from UARS measurements. The intra-seasonal variations with periods between 2 and 4 months have amplitudes close to 2 K, almost half as large as those for the dominant seasonal variations. Their amplitudes are in qualitative agreement with the corresponding values inferred from UARS during different years. The SABER and UARS temperature variations reveal pronounced hemispherical asymmetries, consistent with meridional wind oscillations across the equator. The phase of the semi-annual temperature oscillations from the NSM agrees with the observations from UARS and SABER. But the amplitudes are systematically smaller, which may indicate that planetary waves are more important than is allowed for in the model. For the shorter-period intra-seasonal variations, which can be generated by gravity wave drag, the model results are generally in better agreement with the observations.
NASA Astrophysics Data System (ADS)
Hofmann, Markus J.; Kuchinke, Lars
2015-06-01
While the emotional trias of brainstem, diencephalon, and orbitofrontal cortex is generally accepted to hold an affective function at its core, fewer researchers would agree that the least common denominator function of the hippocampus is affective [1]. There is a greater consensus on complementary learning systems theory proposing that in contrast to the outer cerebral cortex hosting more stable memories, synaptic associations in the hippocampus create novel knowledge in the context of episodic memories [2]. We chose Oscar Wilde's quote [3, p. 108] as title because we think that the novel hippocampal conjunction of for the most part familiar (long-term) knowledge patterns elicits the positive affect of appreciation [4,5].
NASA Technical Reports Server (NTRS)
Turner, T. J.; Weaver, K. A.; Mushotzky, R. F.; Holt, S. S.; Madejski, G. M.
1991-01-01
The X-ray spectra of 25 Seyfert galaxies measured with the Solid State Spectrometer on the Einstein Observatory have been investigated. This new investigation utilizes simultaneous data from the Monitor Proportional Counter, and automatic correction for systematic effects in the Solid State Spectrometer which were previously handled subjectively. It is found that the best-fit single-power-law indices generally agree with those previously reported, but that soft excesses of some form are inferred for about 48 percent of the sources. One possible explanation of the soft excess emission is a blend of soft X-ray lines, centered around 0.8 keV. The implications of these results for accretion disk models are discussed.
Structure-preserving operators for thermal-nonequilibrium hydrodynamics
NASA Astrophysics Data System (ADS)
Shiroto, Takashi; Kawai, Soshi; Ohnishi, Naofumi
2018-07-01
Radiation hydrodynamics simulations based on a single fluid two-temperature model may violate the law of energy conservation, because the governing equations are expressed in a nonconservative formulation. In this study, we maintain the important physical requirements by employing a strategy based on the key concept that mathematical structures associated with conservative and nonconservative equations are preserved, even at the discrete level. To this end, we discretize the conservation laws and transform them using exact algebraic operations. The proposed scheme maintains global conservation errors within the round-off level. In addition, a numerical experiment concerning the shock tube problem suggests that the proposed scheme agrees well with the jump conditions at the discontinuities regulated by the Rankine-Hugoniot relationship. The generalized derivation allows us to employ arbitrary central difference, artificial dissipation, and Runge-Kutta methods.
NASA Technical Reports Server (NTRS)
Beagley, Stephen R.; Degrandpre, Jean; Mcconnell, John C.; Laprise, Rene; Mcfarlane, Norman
1994-01-01
The Canadian Climate Center (CCC) GCM has been modified to allow its use for studies in atmospheric chemistry. The initial experiments reported here have been run to test and allow sensitivity studies of the new transport module. The impact of different types of parameterization for the convective mixing have been studied based on the large scale evolution of Rn-222 and Pb-210. Preliminary results have shown that the use of a scheme, which mixes unstable columns over a very short time scale, produces a global distribution of lead that agrees in some aspects with observations. The local impact of different mixing schemes on a short lived tracer like the radon is very important.
The origins of cosmic rays and quantum effects on gravity
NASA Technical Reports Server (NTRS)
Tomozawa, Y.
1985-01-01
The energy spectrum of primary cosmic rays is explained by particles emitted during a thermal expansion of explosive objects inside and near the galaxy, remnants of which may be supernova and/or active talaxies, or even stars or galaxies that disappeared from our sight after the explosion. A power law energy spectrum for cosmic rays, E to the (-alpha -1, is obtained from an expansion rate T is proportional to R to the alpha. Using the solution of the Einstein equation, we obtain a spectrum which agrees very well with experimental data. The implication of an inflationary early universe on the cosmic ray spectrum is also discussed. It is also suggested that the conflict between this model and the singularity theorem in classical general relativity may be eliminated by quantum effects.
Ferrando Piera, Pere Joan; Gutiérrez-Colón Plana, Mar; Paleo Cageao, Paloma; de la Flor López, Silvia; Ferrando Piera, Francesc
2013-01-01
The reason for this study was the low interest that high school students, particularly females, show for the subject of mechanical engineering (ME). We assumed that this problem was partly due to: (a) lack of understanding of the tasks involved in ME, and (b) a distorted and negative perception of the professional environment and working conditions. To assess these two assumptions, two measurement instruments (tasks and perceptions) were developed and administered in a sample of 496 high school students. A multiple-group design was used and data was analyzed by using an extended item response theory model. In general terms, the results agreed with our expectations. However, no significant gender differences were found. The implications of the results for future improvements are discussed.
MODELING THE SOLAR WIND AT THE ULYSSES , VOYAGER , AND NEW HORIZONS SPACECRAFT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, T. K.; Pogorelov, N. V.; Zank, G. P.
The outer heliosphere is a dynamic region shaped largely by the interaction between the solar wind and the interstellar medium. While interplanetary magnetic field and plasma observations by the Voyager spacecraft have significantly improved our understanding of this vast region, modeling the outer heliosphere still remains a challenge. We simulate the three-dimensional, time-dependent solar wind flow from 1 to 80 astronomical units (au), where the solar wind is assumed to be supersonic, using a two-fluid model in which protons and interstellar neutral hydrogen atoms are treated as separate fluids. We use 1 day averages of the solar wind parameters frommore » the OMNI data set as inner boundary conditions to reproduce time-dependent effects in a simplified manner which involves interpolation in both space and time. Our model generally agrees with Ulysses data in the inner heliosphere and Voyager data in the outer heliosphere. Ultimately, we present the model solar wind parameters extracted along the trajectory of the New Horizons spacecraft. We compare our results with in situ plasma data taken between 11 and 33 au and at the closest approach to Pluto on 2015 July 14.« less
Numerical model for the thermal behavior of thermocline storage tanks
NASA Astrophysics Data System (ADS)
Ehtiwesh, Ismael A. S.; Sousa, Antonio C. M.
2018-03-01
Energy storage is a critical factor in the advancement of solar thermal power systems for the sustained delivery of electricity. In addition, the incorporation of thermal energy storage into the operation of concentrated solar power systems (CSPs) offers the potential of delivering electricity without fossil-fuel backup even during peak demand, independent of weather conditions and daylight. Despite this potential, some areas of the design and performance of thermocline systems still require further attention for future incorporation in commercial CSPs, particularly, their operation and control. Therefore, the present study aims to develop a simple but efficient numerical model to allow the comprehensive analysis of thermocline storage systems aiming better understanding of their dynamic temperature response. The validation results, despite the simplifying assumptions of the numerical model, agree well with the experiments for the time evolution of the thermocline region. Three different cases are considered to test the versatility of the numerical model; for the particular type of a storage tank with top round impingement inlet, a simple analytical model was developed to take into consideration the increased turbulence level in the mixing region. The numerical predictions for the three cases are in general good agreement against the experimental results.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Settlement. 2430.10 Section 2430.10... FEDERAL LABOR RELATIONS AUTHORITY AWARDS OF ATTORNEY FEES AND OTHER EXPENSES § 2430.10 Settlement. The applicant and the General Counsel may agree on a proposed settlement of the award before final action on the...
Code of Federal Regulations, 2010 CFR
2010-07-01
... 29 Labor 2 2010-07-01 2010-07-01 false Settlement. 102.151 Section 102.151 Labor Regulations... Expenses § 102.151 Settlement. The applicant and the General Counsel may agree on a proposed settlement of... on a proposed settlement of an award before an application has been filed, the proposed settlement...
24 CFR 291.100 - General policy.
Code of Federal Regulations, 2010 CFR
2010-04-01
... “asking price,” assigned to the property is based upon an appraisal conducted by an independent real... seller, as mortgagee, as part of the purchase price of the real estate. (e) Environmental requirements...) Listings. Any real estate broker who has agreed to comply with HUD requirements may participate in the...
47 CFR 11.19 - EAS Non-participating National Authorization Letter.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 1 2010-10-01 2010-10-01 false EAS Non-participating National Authorization Letter. 11.19 Section 11.19 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EMERGENCY ALERT... level EAS. It states that the EAS Participant has agreed to go off the air or discontinue programming on...
47 CFR 11.19 - EAS Non-participating National Authorization Letter.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 1 2011-10-01 2011-10-01 false EAS Non-participating National Authorization Letter. 11.19 Section 11.19 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EMERGENCY ALERT... level EAS. It states that the EAS Participant has agreed to go off the air or discontinue programming on...
The Contribution of IUPAC to Polymer Science Education
ERIC Educational Resources Information Center
Chan, Chin Han; Fellows, Christopher M.; Hess, Michael; Hiorns, Roger; Hoven, Voravee P.; Russell, Gregory T.; dos Santos, Cla´udio G.; S?turcova´, Adriana; Theato, Patrick
2017-01-01
Polymer education relies on generally agreed terminology and nomenclature rules. The Polymer Division of the International Union of Pure and Applied Chemistry (IUPAC) generates and recommends such rules for naming processes and materials in polymer science. It is the goal of IUPAC that these recommendations be applied in polymer science curricula…
7 CFR 1710.113 - Loan security.
Code of Federal Regulations, 2013 CFR
2013-01-01
... within the time agreed. (b) RUS generally requires that borrowers provide it with a first lien on all of the borrower's real and personal property, including intangible personal property and any property... entire system the Administrator may accept other forms of security, such as a pledge of revenues, if he...
7 CFR 1710.113 - Loan security.
Code of Federal Regulations, 2011 CFR
2011-01-01
... within the time agreed. (b) RUS generally requires that borrowers provide it with a first lien on all of the borrower's real and personal property, including intangible personal property and any property... entire system the Administrator may accept other forms of security, such as a pledge of revenues, if he...
7 CFR 1710.113 - Loan security.
Code of Federal Regulations, 2012 CFR
2012-01-01
... within the time agreed. (b) RUS generally requires that borrowers provide it with a first lien on all of the borrower's real and personal property, including intangible personal property and any property... entire system the Administrator may accept other forms of security, such as a pledge of revenues, if he...
7 CFR 1710.113 - Loan security.
Code of Federal Regulations, 2014 CFR
2014-01-01
... within the time agreed. (b) RUS generally requires that borrowers provide it with a first lien on all of the borrower's real and personal property, including intangible personal property and any property... entire system the Administrator may accept other forms of security, such as a pledge of revenues, if he...
Students' Experience in a General Chemistry Cooperative Problem Based Laboratory
ERIC Educational Resources Information Center
Sandi-Urena, Santiago; Cooper, Melanie M.; Gatlin, Todd A.; Bhattacharyya, Gautam
2011-01-01
Most educators and scientists would agree that science laboratory instruction has the potential of developing science practices fundamental to achieving scientific literacy. However, there is scant evidence to support that this potential is realized, particularly in tertiary level education. This paper reports qualitative results from a sequential…
10 CFR Appendix A to Part 824 - General Statement of Enforcement Policy
Code of Federal Regulations, 2010 CFR
2010-01-01
... positive incentives for a DOE contractor's: (1) Timely self-identification of security deficiencies, (2..., when verification is received that corrective actions have been implemented, DOE will close the... Administrator who agrees that further enforcement action should not be pursued if verification is received that...
75 FR 82576 - Federal Acquisition Regulation; Terminating Contracts
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-30
... Acquisition Council (Councils) agree. The language at FAR 49.501, pertaining to the applicability of FAR part...-AL56 Federal Acquisition Regulation; Terminating Contracts AGENCY: Department of Defense (DoD), General.... SUMMARY: DoD, GSA, and NASA are issuing a final rule amending the Federal Acquisition Regulation (FAR) to...
Code of Federal Regulations, 2010 CFR
2010-10-01
... DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION FREEDOM OF INFORMATION REGULATIONS Fees § 5.43... punchcards or blueprints), or reproducing other records (such as tapes)—the actual costs of operating the... service is not required by the FOIA. If we agree to provide it, we will charge $10 per certification. (f...
14 CFR 1214.104 - Reimbursement for optional services.
Code of Federal Regulations, 2012 CFR
2012-01-01
... General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable... be escalated in accordance with the provisions of § 1214.103(d). (c) Schedules of payments. NASA will... agreement at the time a particular optional service is agreed to between the customer and NASA. (d) Late...
14 CFR 1214.104 - Reimbursement for optional services.
Code of Federal Regulations, 2010 CFR
2010-01-01
... General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable... be escalated in accordance with the provisions of § 1214.103(d). (c) Schedules of payments. NASA will... agreement at the time a particular optional service is agreed to between the customer and NASA. (d) Late...
14 CFR 1214.104 - Reimbursement for optional services.
Code of Federal Regulations, 2011 CFR
2011-01-01
... General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable... be escalated in accordance with the provisions of § 1214.103(d). (c) Schedules of payments. NASA will... agreement at the time a particular optional service is agreed to between the customer and NASA. (d) Late...
14 CFR 1214.104 - Reimbursement for optional services.
Code of Federal Regulations, 2013 CFR
2013-01-01
... General Provisions Regarding Space Shuttle Flights of Payloads for Non-U.S. Government, Reimbursable... be escalated in accordance with the provisions of § 1214.103(d). (c) Schedules of payments. NASA will... agreement at the time a particular optional service is agreed to between the customer and NASA. (d) Late...
Paradise Lost: Age-Dependent Mortality of American Communes, 1609-1965
ERIC Educational Resources Information Center
Kitts, James A.
2009-01-01
Theorists agree that the risk of folding changes as organizations age, but there is little consensus as to the general form or generative processes of age-dependent mortality. This article investigates four such processes (maturation, senescence, legitimation and obsolescence), which have been taken as competing accounts. Using two analytical…
40 CFR 35.3550 - Specific capitalization grant agreement requirements.
Code of Federal Regulations, 2010 CFR
2010-07-01
... accounting system used for the DWSRF program must allow for proper measurement of: (1) Revenues earned and... services. (i) Use generally accepted accounting principles. A State must agree to ensure that the State and public water systems receiving assistance will use accounting, audit, and fiscal procedures conforming to...
32 CFR 644.354 - Conditional reports of excess.
Code of Federal Regulations, 2012 CFR
2012-07-01
... general policy, GSA has agreed with the Department of Defense to accept reports of excess on some... 32 National Defense 4 2012-07-01 2011-07-01 true Conditional reports of excess. 644.354 Section 644.354 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL...
32 CFR 644.354 - Conditional reports of excess.
Code of Federal Regulations, 2014 CFR
2014-07-01
... general policy, GSA has agreed with the Department of Defense to accept reports of excess on some... 32 National Defense 4 2014-07-01 2013-07-01 true Conditional reports of excess. 644.354 Section 644.354 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL...
32 CFR 644.354 - Conditional reports of excess.
Code of Federal Regulations, 2013 CFR
2013-07-01
... general policy, GSA has agreed with the Department of Defense to accept reports of excess on some... 32 National Defense 4 2013-07-01 2013-07-01 false Conditional reports of excess. 644.354 Section 644.354 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL...
32 CFR 644.354 - Conditional reports of excess.
Code of Federal Regulations, 2011 CFR
2011-07-01
... general policy, GSA has agreed with the Department of Defense to accept reports of excess on some... 32 National Defense 4 2011-07-01 2011-07-01 false Conditional reports of excess. 644.354 Section 644.354 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL...
32 CFR 644.354 - Conditional reports of excess.
Code of Federal Regulations, 2010 CFR
2010-07-01
... general policy, GSA has agreed with the Department of Defense to accept reports of excess on some... 32 National Defense 4 2010-07-01 2010-07-01 true Conditional reports of excess. 644.354 Section 644.354 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) REAL...
ERIC Educational Resources Information Center
Manzo, Kathleen Kennedy
2005-01-01
While researchers generally agree that literacy skills should be taught directly to adolescents across the curriculum, and that there are adequate research-based strategies for doing so, expets point out that much of that information has failed to reach the classroom, or has been ignored by teachers, who are either ill prepared or disinclined to…
Rep. Ryan, Paul [R-WI-1
2014-04-04
Senate - 04/11/2014 Placed on Senate Legislative Calendar under General Orders. Calendar No. 365. (All Actions) Tracker: This bill has the status Agreed to in HouseHere are the steps for Status of Legislation:
7 CFR 1703.111 - Grant and loan termination.
Code of Federal Regulations, 2012 CFR
2012-01-01
... AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Loan and Grant Program-General § 1703.111... agree upon the conditions of the termination, the effective date of the termination, and, in the case of... such termination, the effective date, and, in the case of a partial termination, the portion of the...
7 CFR 1703.111 - Grant and loan termination.
Code of Federal Regulations, 2011 CFR
2011-01-01
... AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Loan and Grant Program-General § 1703.111... agree upon the conditions of the termination, the effective date of the termination, and, in the case of... such termination, the effective date, and, in the case of a partial termination, the portion of the...
7 CFR 1703.111 - Grant and loan termination.
Code of Federal Regulations, 2013 CFR
2013-01-01
... AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Loan and Grant Program-General § 1703.111... agree upon the conditions of the termination, the effective date of the termination, and, in the case of... such termination, the effective date, and, in the case of a partial termination, the portion of the...
7 CFR 1703.111 - Grant and loan termination.
Code of Federal Regulations, 2014 CFR
2014-01-01
... AGRICULTURE RURAL DEVELOPMENT Distance Learning and Telemedicine Loan and Grant Program-General § 1703.111... agree upon the conditions of the termination, the effective date of the termination, and, in the case of... such termination, the effective date, and, in the case of a partial termination, the portion of the...
Making University Financial Reports Informative and Meaningful.
ERIC Educational Resources Information Center
Gilmore, Robert B.
1970-01-01
The National Association of College and University Business Officers has taken major strides toward meeting the responsibility for establishing accounting and public reporting standards within the field of higher education. The need for improvement in the reporting procedures has been generally agreed on. It is imperative that revision of the…
Serotonin: Modulator of a Drive to Withdraw
ERIC Educational Resources Information Center
Tops, Mattie; Russo, Sascha; Boksem, Maarten A. S.; Tucker, Don M.
2009-01-01
Serotonin is a fundamental neuromodulator in both vertebrate and invertebrate nervous systems, with a suspected role in many human mental disorders. Yet, because of the complexity of serotonergic function, researchers have been unable to agree on a general theory. One function suggested for serotonin systems is the avoidance of threat. We propose…
Capacity Building for Social Innovation: A Collective Impact Approach
ERIC Educational Resources Information Center
Szarleta, Ellen J.
2017-01-01
Business, nonprofit, and government institutions generally agree that a vibrant economy is critical to addressing the multi-faceted, complex issues faced by urban communities. Yet, despite significant targeted efforts aimed at revitalizing economic activity over the past few decades, the state of many communities remains unchanged. A collective…
The Emergence of Ethics and Professionalism in the Early Advertising Business.
ERIC Educational Resources Information Center
Schultze, Quentin J.
In the pre-World War I era, advertising practitioners attempted to make their craft a profession. Generally agreeing that the creation of ethical codes was the most important step toward professionalism, practitioners organized the Associated Advertising Clubs of America (AACA). Early journal articles and AACA proceedings indicate that…
Improving Sustainable Living Education through the Use of Formative Experiments
ERIC Educational Resources Information Center
Wynveen, Brooklynn J.
2017-01-01
Experts agree that overconsumption is a major problem in Western culture today, particularly in the United States. Thus, it is important to promote sustainable behaviour among the general public. However, existing educational programming geared towards promoting such behaviour remains appealing largely to environmentally motivated audiences, as…
Evaluating the Skill of Students to Determine Soil Morphology Characteristics
ERIC Educational Resources Information Center
Post, Donald F.; Parikh, Sanjai J.; Papp, Rae Ann; Ferriera, Laerta
2006-01-01
Precise and accurate pedon descriptions prepared by field scientists using standard techniques with defined terminology and methodology are essential in describing soil pedons. The accuracy of field measurements generally are defined in terms of how well they agree with objective criteria (e.g., laboratory analysis), such as mechanical analysis…
Genetic Effects on Human Behavior: Recent Family Studies.
ERIC Educational Resources Information Center
Scarr, Sandra
Although there continues to be controversy about the magnitude of genetic and environmental effects on human behavior, it is generally agreed by various scientific fields that individual differences in brain function and behavior must follow the same laws of variability as other human characteristics. Whether or not racial and ethnic group…
Theory-Based Considerations Influence the Interpretation of Generic Sentences
ERIC Educational Resources Information Center
Cimpian, Andrei; Gelman, Susan A.; Brandone, Amanda C.
2010-01-01
Under what circumstances do people agree that a kind-referring generic sentence (e.g., "Swans are beautiful") is true? We hypothesised that theory-based considerations are sufficient, independently of prevalence/frequency information, to lead to acceptance of a generic statement. To provide evidence for this general point, we focused on…
7 CFR 1710.113 - Loan security.
Code of Federal Regulations, 2010 CFR
2010-01-01
... within the time agreed. (b) RUS generally requires that borrowers provide it with a first lien on all of the borrower's real and personal property, including intangible personal property and any property... entire system the Administrator may accept other forms of security, such as a pledge of revenues, if he...
Teaching Social Skills: An Effective Online Program
ERIC Educational Resources Information Center
Sanchez, Rebecca P.; Brown, Emily; DeRosier, Melissa E.
2015-01-01
Educators, policymakers, and the general public agree that social skills should be taught to children. In an effort to bridge this gap between evidence-based social skills training and populations in need, the authors have developed an Intelligent Social Tutoring System (ISTS) that fosters learning through adaptive interaction between the student…
ERIC Educational Resources Information Center
Seipel, Michael M. O.; Johnson, Jennifer D.; Walton, Elaine
2011-01-01
Selecting the best students and hiring the best social workers are important professional responsibilities. Findings from this exploratory study identify personal attributes that are significant in enabling MSW students and social work employees to succeed. Social work educators and agency administrators generally agree that personal attributes…
On Teaching a Fractured Macroeconomics: A Comment.
ERIC Educational Resources Information Center
Soper, John C.
1987-01-01
Offers an analysis of Galbraith's article (see SO516716) agreeing mostly with the major points it makes concerning the limitations of the concept lists and the general lack of content illustrating the competing theories. Offers data showing what is learned by high school students regarding certain economic concepts. (JDH)
The Legal Aspects of Student Discipline in Higher Education.
ERIC Educational Resources Information Center
Young, D. Parker
The proliferation of court cases involving student discipline testifies to controversy over administrative procedures. Generally, a college's disciplinary policy is viewed as part of the learning process. Courts in the past have ruled favorably on the contractual theory which decrees that an entering student agrees to abide by certain university…
EUnetHTA information management system: development and lessons learned.
Chalon, Patrice X; Kraemer, Peter
2014-11-01
The aim of this study was to describe the techniques used in achieving consensus on common standards to be implemented in the EUnetHTA Information Management System (IMS); and to describe how interoperability between tools was explored. Three face to face meetings were organized to identify and agree on common standards to the development of online tools. Two tools were created to demonstrate the added value of implementing interoperability standards at local levels. Developers of tools outside EUnetHTA were identified and contacted. Four common standards have been agreed on by consensus; and consequently all EUnetHTA tools have been modified or designed accordingly. RDF Site Summary (RSS) has demonstrated a good potential to support rapid dissemination of HTA information. Contacts outside EUnetHTA resulted in direct collaboration (HTA glossary, HTAi Vortal), evaluation of options for interoperability between tools (CRD HTA database) or a formal framework to prepare cooperation on concrete projects (INAHTA projects database). While being entitled a project on IT infrastructure, the work program was also about people. When having to agree on complex topics, fostering a cohesive group dynamic and hosting face to face meetings brings added value and enhances understanding between partners. The adoption of widespread standards enhanced the homogeneity of the EUnetHTA tools and should thus contribute to their wider use, therefore, to the general objective of EUnetHTA. The initiatives on interoperability of systems need to be developed further to support a general interoperable information system that could benefit the whole HTA community.
Mushkudiani, Nino A; Hukkelhoven, Chantal W P M; Hernández, Adrián V; Murray, Gordon D; Choi, Sung C; Maas, Andrew I R; Steyerberg, Ewout W
2008-04-01
To describe the modeling techniques used for early prediction of outcome in traumatic brain injury (TBI) and to identify aspects for potential improvements. We reviewed key methodological aspects of studies published between 1970 and 2005 that proposed a prognostic model for the Glasgow Outcome Scale of TBI based on admission data. We included 31 papers. Twenty-four were single-center studies, and 22 reported on fewer than 500 patients. The median of the number of initially considered predictors was eight, and on average five of these were selected for the prognostic model, generally including age, Glasgow Coma Score (or only motor score), and pupillary reactivity. The most common statistical technique was logistic regression with stepwise selection of predictors. Model performance was often quantified by accuracy rate rather than by more appropriate measures such as the area under the receiver-operating characteristic curve. Model validity was addressed in 15 studies, but mostly used a simple split-sample approach, and external validation was performed in only four studies. Although most models agree on the three most important predictors, many were developed on small sample sizes within single centers and hence lack generalizability. Modeling strategies have to be improved, and include external validation.
Kempenich, Jason W; Willis, Ross E; Rakosi, Robert; Wiersch, John; Schenarts, Paul Joseph
2015-01-01
Identify barriers to resident autonomy in today's educational environment as perceived through 4 selected groups: senior surgical residents, teaching faculty, hospital administration, and the general public. Anonymous surveys were created and distributed to senior residents, faculty, and hospital administrators working within 3 residency programs. The opinions of a convenience sample of the general public were also assessed using a similar survey. Keesler Medical Center, Keesler AFB, MS; the University of Texas Health Science of San Antonio, TX; and the University of Nebraska Medical Center, Omaha, NE. A total of 169 responses were collected: 32 residents, 50 faculty, 20 administrators, and 67 general public. Faculty and residents agree that when attending staff grant more autonomy, residents' self-confidence and sense of ownership improve. Faculty felt that residents should have less autonomy than residents did (p < 0.001). When asked to reflect on the current level of autonomy at their institution, 47% of residents felt that they had too little autonomy and 38% of faculty agreed. No resident or faculty felt that residents had too much autonomy at their institution. The general public were more welcoming of resident participation than faculty (p = 0.002) and administrators (p = 0.02) predicted they would be. When the general public were asked regarding their opinions about resident participation with complex procedures, they were less welcoming than faculty, administrators, and residents thought (p < 0.001). The general public were less likely to think that resident involvement would improve their quality of care (p < 0.001). Faculty and senior residents both endorse resident autonomy as important for resident development. The general public are more receptive to resident participation than anticipated. However, with increasing procedural complexity and resident independence, they were less inclined to have residents involved. The general public also had more concerns regarding quality of care provided by residents than the other groups had. Published by Elsevier Inc.
NASA Astrophysics Data System (ADS)
Zunz, Violette; Goosse, Hugues; Dubinkina, Svetlana
2013-04-01
The sea ice extent in the Southern Ocean has increased since 1979 but the causes of this expansion have not been firmly identified. In particular, the contribution of internal variability and external forcing to this positive trend has not been fully established. In this region, the lack of observations and the overestimation of internal variability of the sea ice by contemporary General Circulation Models (GCMs) make it difficult to understand the behaviour of the sea ice. Nevertheless, if its evolution is governed by the internal variability of the system and if this internal variability is in some way predictable, a suitable initialization method should lead to simulations results that better fit the reality. Current GCMs decadal predictions are generally initialized through a nudging towards some observed fields. This relatively simple method does not seem to be appropriated to the initialization of sea ice in the Southern Ocean. The present study aims at identifying an initialization method that could improve the quality of the predictions of Southern Ocean sea ice at decadal timescales. We use LOVECLIM, an Earth-system Model of Intermediate Complexity that allows us to perform, within a reasonable computational time, the large amount of simulations required to test systematically different initialization procedures. These involve three data assimilation methods: a nudging, a particle filter and an efficient particle filter. In a first step, simulations are performed in an idealized framework, i.e. data from a reference simulation of LOVECLIM are used instead of observations, herein after called pseudo-observations. In this configuration, the internal variability of the model obviously agrees with the one of the pseudo-observations. This allows us to get rid of the issues related to the overestimation of the internal variability by models compared to the observed one. This way, we can work out a suitable methodology to assess the efficiency of the initialization procedures tested. It also allows us determine the upper limit of improvement that can be expected if more sophisticated initialization methods are used in decadal prediction simulations and if models have an internal variability agreeing with the observed one. Furthermore, since pseudo-observations are available everywhere at any time step, we also analyse the differences between simulations initialized with a complete dataset of pseudo-observations and the ones for which pseudo-observations data are not assimilated everywhere. In a second step, simulations are realized in a realistic framework, i.e. through the use of actual available observations. The same data assimilation methods are tested in order to check if more sophisticated methods can improve the reliability and the accuracy of decadal prediction simulations, even if they are performed with models that overestimate the internal variability of the sea ice extent in the Southern Ocean.
Schiff, Elad; Ben-Arye, Eran; Shilo, Margalit; Levy, Moti; Schachter, Leora; Weitchner, Na'ama; Golan, Ofra; Stone, Julie
2011-02-01
Recently, ethical guidelines regarding safe touch in CAM were developed in Israel. Publishing ethical codes does not imply that they will actually help practitioners to meet ethical care standards. The effectiveness of ethical rules depends on familiarity with the code and its content. In addition, critical self-examination of the code by individual members of the profession is required to reflect on the moral commitments encompassed in the code. For the purpose of dynamic self-appraisal, we devised a survey to assess how CAM practitioners view the suggested ethical guidelines for safe touch. We surveyed 781 CAM practitioners regarding their perspectives on the safe-touch code. There was a high level of agreement with general statements regarding ethics pertaining to safe touch with a mean rate of agreement of 4.61 out of a maximum of 5. Practitioners concurred substantially with practice guidelines for appropriate touch with a mean rate of agreement of 4.16 out of a maximum of 5. Attitudes toward the necessity to touch intimate areas for treatment purposes varied with 78.6% of respondents strongly disagreeing with any notion of need to touch intimate areas during treatment. 7.9% neither disagreed nor agreed, 7.9% slightly agreed, and 7.6% strongly agreed with the need for touching intimate areas during treatment. There was a direct correlation between disagreement with touching intimate areas for therapeutic purposes and agreement with general statements regarding ethics of safe touch (Spearman r=0.177, p<0.0001), and practice guidelines for appropriate touch (r=0.092, p=0.012). A substantial number of practitioners agreed with the code, although some findings regarding the need to touch intimate area during treatments were disturbing. Our findings can serve as a basis for ethical code development and implementation, as well as for educating CAM practitioners on the ethics of touch. Copyright © 2010 Elsevier Ltd. All rights reserved.
An Analytical Approach to Obtaining JWL Parameters from Cylinder Tests
NASA Astrophysics Data System (ADS)
Sutton, Ben; Ferguson, James
2015-06-01
An analytical method for determining parameters for the JWL equation of state (EoS) from cylinder test data is described. This method is applied to four datasets obtained from two 20.3 mm diameter EDC37 cylinder tests. The calculated parameters and pressure-volume (p-V) curves agree with those produced by hydro-code modelling. The calculated Chapman-Jouguet (CJ) pressure is 38.6 GPa, compared to the model value of 38.3 GPa; the CJ relative volume is 0.729 for both. The analytical pressure-volume curves produced agree with the one used in the model out to the commonly reported expansion of 7 relative volumes, as do the predicted energies generated by integrating under the p-V curve. The calculated and model energies are 8.64 GPa and 8.76 GPa respectively.
Sen. Inouye, Daniel K. [D-HI
2010-07-19
Senate - 07/22/2010 Resolution agreed to in Senate without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:
Alduraywish, Abdulrahman Abdulwahab; Mohager, Mazin Omer; Alenezi, Mohammed Jayed; Nail, Abdelsalam Mohammed; Aljafari, Alfatih Saifudinn
2017-12-01
To evaluate the students' experience with problem-based learning. This cross-sectional, qualitative study was conducted at the College of Medicine, Al Jouf University, Sakakah, Saudi Arabia, in October 2015, and comprised medical students of the 1st to 5th levels. Interviews were conducted using Students' Course Experience Questionnaire. The questionnaire contained 37 questions covering six evaluative categories: appropriate assessment, appropriate workload, clear goals and standards, generic skills, good teaching, and overall satisfaction. The questionnaire follows the Likert's scale model. Mean values were interpreted as: >2.5= at least disagree, 2.5->3= neither/nor (uncertain), and 3 or more= at least agree. Of the 170 respondents, 72(42.7%) agreed that there was an appropriate assessment accompanied with the problem-based learning. Also, 107(63.13%) students agreed that there was a heavy workload on them. The goal and standards of the course were clear for 71(42.35%) students, 104(61.3%) agreed that problem-based learning improved their generic skills, 65(38.07%) agreed the teaching was good and 82(48.08%) students showed overall satisfaction. The students were satisfied with their experience with the problem-based learning.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Garcia, E. V.; Stassun, Keivan G.; Pavlovski, K.
We determine the absolute dimensions of the eclipsing binary V578 Mon, a detached system of two early B-type stars (B0V + B1V, P = 2.40848 days) in the star-forming region NGC 2244 of the Rosette Nebula. From the light curve analysis of 40 yr of photometry and the analysis of HERMES spectra, we find radii of 5.41 ± 0.04 R{sub ☉} and 4.29 ± 0.05 R{sub ☉}, and temperatures of 30,000 ± 500 K and 25,750 ± 435 K, respectively. We find that our disentangled component spectra for V578 Mon agree well with previous spectral disentangling from the literature. Wemore » also reconfirm the previous spectroscopic orbit of V578 Mon finding that masses of 14.54 ± 0.08 M{sub ☉} and 10.29 ± 0.06 M{sub ☉} are fully compatible with the new analysis. We compare the absolute dimensions to the rotating models of the Geneva and Utrecht groups and the models of the Granada group. We find that all three sets of models marginally reproduce the absolute dimensions of both stars with a common age within the uncertainty for gravity-effective temperature isochrones. However, there are some apparent age discrepancies for the corresponding mass-radius isochrones. Models with larger convective overshoot, >0.35, worked best. Combined with our previously determined apsidal motion of 0.07089{sub −0.00013}{sup +0.00021} deg cycle{sup –1}, we compute the internal structure constants (tidal Love number) for the Newtonian and general relativistic contribution to the apsidal motion as log k {sub 2} = –1.975 ± 0.017 and log k {sub 2} = –3.412 ± 0.018, respectively. We find the relativistic contribution to the apsidal motion to be small, <4%. We find that the prediction of log k {sub 2,theo} = –2.005 ± 0.025 of the Granada models fully agrees with our observed log k {sub 2}.« less
Homogenized modeling methodology for 18650 lithium-ion battery module under large deformation
Tang, Liang; Cheng, Pengle
2017-01-01
Effective lithium-ion battery module modeling has become a bottleneck for full-size electric vehicle crash safety numerical simulation. Modeling every single cell in detail would be costly. However, computational accuracy could be lost if the module is modeled by using a simple bulk material or rigid body. To solve this critical engineering problem, a general method to establish a computational homogenized model for the cylindrical battery module is proposed. A single battery cell model is developed and validated through radial compression and bending experiments. To analyze the homogenized mechanical properties of the module, a representative unit cell (RUC) is extracted with the periodic boundary condition applied on it. An elastic–plastic constitutive model is established to describe the computational homogenized model for the module. Two typical packing modes, i.e., cubic dense packing and hexagonal packing for the homogenized equivalent battery module (EBM) model, are targeted for validation compression tests, as well as the models with detailed single cell description. Further, the homogenized EBM model is confirmed to agree reasonably well with the detailed battery module (DBM) model for different packing modes with a length scale of up to 15 × 15 cells and 12% deformation where the short circuit takes place. The suggested homogenized model for battery module makes way for battery module and pack safety evaluation for full-size electric vehicle crashworthiness analysis. PMID:28746390
Homogenized modeling methodology for 18650 lithium-ion battery module under large deformation.
Tang, Liang; Zhang, Jinjie; Cheng, Pengle
2017-01-01
Effective lithium-ion battery module modeling has become a bottleneck for full-size electric vehicle crash safety numerical simulation. Modeling every single cell in detail would be costly. However, computational accuracy could be lost if the module is modeled by using a simple bulk material or rigid body. To solve this critical engineering problem, a general method to establish a computational homogenized model for the cylindrical battery module is proposed. A single battery cell model is developed and validated through radial compression and bending experiments. To analyze the homogenized mechanical properties of the module, a representative unit cell (RUC) is extracted with the periodic boundary condition applied on it. An elastic-plastic constitutive model is established to describe the computational homogenized model for the module. Two typical packing modes, i.e., cubic dense packing and hexagonal packing for the homogenized equivalent battery module (EBM) model, are targeted for validation compression tests, as well as the models with detailed single cell description. Further, the homogenized EBM model is confirmed to agree reasonably well with the detailed battery module (DBM) model for different packing modes with a length scale of up to 15 × 15 cells and 12% deformation where the short circuit takes place. The suggested homogenized model for battery module makes way for battery module and pack safety evaluation for full-size electric vehicle crashworthiness analysis.
Relativistic Outflows from Advection-dominated Accretion Disks around Black Holes
NASA Astrophysics Data System (ADS)
Becker, Peter A.; Subramanian, Prasad; Kazanas, Demosthenes
2001-05-01
Advection-dominated accretion flows (ADAFs) have a positive Bernoulli parameter and are therefore gravitationally unbound. The Newtonian ADAF model has been generalized recently to obtain the ADIOS model that includes outflows of energy and angular momentum, thereby allowing accretion to proceed self-consistently. However, the utilization of a Newtonian gravitational potential limits the ability of this model to describe the inner region of the disk, where any relativistic outflows are likely to originate. In this paper we modify the ADIOS scenario to incorporate a pseudo-Newtonian potential, which approximates the effects of general relativity. The analysis yields a unique, self-similar solution for the structure of the coupled disk/wind system. Interesting features of the new solution include the relativistic character of the outflow in the vicinity of the radius of marginal stability, which represents the inner edge of the quasi-Keplerian disk in our model. Hence, our self-similar solution may help to explain the origin of relativistic jets in active galaxies. At large distances the radial dependence of the accretion rate approaches the unique form M~r1/2, with an associated density variation given by ρ~r-1. This density variation agrees with that implied by the dependence of the hard X-ray time lags on the Fourier frequency for a number of accreting galactic black hole candidates. While intriguing, the predictions made using our self-similar solution need to be confirmed in the future using a detailed model that includes a physical description of the energization mechanism that drives the outflow, which is likely to be powered by the shear of the underlying accretion disk.
STRUCTURAL PARAMETERS FOR 10 HALO GLOBULAR CLUSTERS IN M33
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Jun, E-mail: majun@nao.cas.cn
2015-05-15
In this paper, we present the properties of 10 halo globular clusters (GCs) with luminosities L ≃ 5–7 × 10{sup 5} L{sub ⊙} in the Local Group galaxy M33 using images from the Hubble Space Telescope WFPC2 in the F555W and F814W bands. We obtained the ellipticities, position angles, and surface brightness profiles for each GC. In general, the ellipticities of the M33 sample clusters are similar to those of the M31 clusters. The structural and dynamical parameters are derived by fitting the profiles to three different models combined with mass-to-light ratios (M/L values) from population-synthesis models. The structural parametersmore » include core radii, concentration, half-light radii, and central surface brightness. The dynamical parameters include the integrated cluster mass, integrated binding energy, central surface mass density, and predicted line of sight velocity dispersion at the cluster center. The velocity dispersions of the four clusters predicted here agree well with the observed dispersions by Larsen et al. The results here showed that the majority of the sample halo GCs are better fitted by both the King model and the Wilson model than the Sérsic model. In general, the properties of the clusters in M33, M31, and the Milky Way fall in the same regions of parameter spaces. The tight correlations of cluster properties indicate a “fundamental plane” for clusters, which reflects some universal physical conditions and processes operating at the epoch of cluster formation.« less
NASA Astrophysics Data System (ADS)
Zhuk, Ya A.; Senchenkov, I. K.
1999-02-01
Certain aspects of the correct definitions of stress and strain concentration factors for elastic-viscoplastic solids under cyclic loading are discussed. Problems concerning the harmonic kinematic excitation of cylindrical specimens with a lateral V-notch are examined. The behavior of the material of a cylinder is modeled using generalized flow theory. An approximate model based on the concept of complex moduli is used for comparison. Invariant characteristics such as stress and strain intensities and maximum principal stress and strain are chosen as constitutive quantities for concentration-factor definitions. The behavior of time-varying factors is investigated. Concentration factors calculated in terms of the amplitudes of the constitutive quantities are used as representative characteristics over the cycle of vibration. The dependences of the concentration factors on the loads are also studied. The accuracy of Nueber's and Birger's formulas is evaluated. The solution of the problem in the approximate formulation agrees with its solution in the exact formulation. The possibilities of the approximate model for estimating low-cycle fatigue are evaluated.
A united event grand canonical Monte Carlo study of partially doped polyaniline
DOE Office of Scientific and Technical Information (OSTI.GOV)
Byshkin, M. S., E-mail: mbyshkin@unisa.it, E-mail: gmilano@unisa.it; Correa, A.; Buonocore, F.
2013-12-28
A Grand Canonical Monte Carlo scheme, based on united events combining protonation/deprotonation and insertion/deletion of HCl molecules is proposed for the generation of polyaniline structures at intermediate doping levels between 0% (PANI EB) and 100% (PANI ES). A procedure based on this scheme and subsequent structure relaxations using molecular dynamics is described and validated. Using the proposed scheme and the corresponding procedure, atomistic models of amorphous PANI-HCl structures were generated and studied at different doping levels. Density, structure factors, and solubility parameters were calculated. Their values agree well with available experimental data. The interactions of HCl with PANI have beenmore » studied and distribution of their energies has been analyzed. The procedure has also been extended to the generation of PANI models including adsorbed water and the effect of inclusion of water molecules on PANI properties has also been modeled and discussed. The protocol described here is general and the proposed United Event Grand Canonical Monte Carlo scheme can be easily extended to similar polymeric materials used in gas sensing and to other systems involving adsorption and chemical reactions steps.« less
Terrestrial biosphere changes over the last 120 kyr
NASA Astrophysics Data System (ADS)
Hoogakker, B. A. A.; Smith, R. S.; Singarayer, J. S.; Marchant, R.; Prentice, I. C.; Allen, J. R. M.; Anderson, R. S.; Bhagwat, S. A.; Behling, H.; Borisova, O.; Bush, M.; Correa-Metrio, A.; de Vernal, A.; Finch, J. M.; Fréchette, B.; Lozano-Garcia, S.; Gosling, W. D.; Granoszewski, W.; Grimm, E. C.; Grüger, E.; Hanselman, J.; Harrison, S. P.; Hill, T. R.; Huntley, B.; Jiménez-Moreno, G.; Kershaw, P.; Ledru, M.-P.; Magri, D.; McKenzie, M.; Müller, U.; Nakagawa, T.; Novenko, E.; Penny, D.; Sadori, L.; Scott, L.; Stevenson, J.; Valdes, P. J.; Vandergoes, M.; Velichko, A.; Whitlock, C.; Tzedakis, C.
2016-01-01
A new global synthesis and biomization of long (> 40 kyr) pollen-data records is presented and used with simulations from the HadCM3 and FAMOUS climate models and the BIOME4 vegetation model to analyse the dynamics of the global terrestrial biosphere and carbon storage over the last glacial-interglacial cycle. Simulated biome distributions using BIOME4 driven by HadCM3 and FAMOUS at the global scale over time generally agree well with those inferred from pollen data. Global average areas of grassland and dry shrubland, desert, and tundra biomes show large-scale increases during the Last Glacial Maximum, between ca. 64 and 74 ka BP and cool substages of Marine Isotope Stage 5, at the expense of the tropical forest, warm-temperate forest, and temperate forest biomes. These changes are reflected in BIOME4 simulations of global net primary productivity, showing good agreement between the two models. Such changes are likely to affect terrestrial carbon storage, which in turn influences the stable carbon isotopic composition of seawater as terrestrial carbon is depleted in 13C.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Korolev, Yu. D.; Landl, N. V., E-mail: landl@lnp.hcei.tsc.ru; Geyman, V. G.
Results from studies of a low-current glow discharge with a hollow cathode are presented. A specific feature of the discharge conditions was that a highly emissive tablet containing cesium carbonate was placed in the cathode cavity. In the absence of a tablet, the discharge ignition voltage was typically ≥3.5 kV, while the burning voltage was in the range of 500–600 V. The use of the tablet made it possible to decrease the ignition voltage to 280 V and maintain the discharge burning voltage at a level of about 130 V. A model of the current sustainment in a hollow-cathode dischargemore » is proposed. Instead of the conventional secondary emission yield, the model uses a generalized emission yield that takes into account not only ion bombardment of the cathode, but also the emission current from an external source. The model is used to interpret the observed current−voltage characteristics. The results of calculations agree well with the experimental data. It is shown that, in some discharge modes, the external emission current from the cathode can reach 25% of the total discharge current.« less
Literature review of outcome parameters used in studies of Geriatric Fracture Centers.
Liem, I S L; Kammerlander, C; Suhm, N; Kates, S L; Blauth, M
2014-02-01
A variety of multidisciplinary treatment models have been described to improve outcome after osteoporotic hip fractures. There is a tendency toward better outcomes after implementation of the most sophisticated model with a shared leadership for orthopedic surgeons and geriatricians; the Geriatric Fracture Center. The purpose of this review is to evaluate the use of outcome parameters in published literature on the Geriatric Fracture Center evaluation studies. A literature search was performed using Medline and the Cochrane Library to identify Geriatric Fracture Center evaluation studies. The outcome parameters used in the included studies were evaluated. A total of 16 outcome parameters were used in 11 studies to evaluate patient outcome in 8 different Geriatric Fracture Centers. Two of these outcome parameters are patient-reported outcome measures and 14 outcome parameters were objective measures. In-hospital mortality, length of stay, time to surgery, place of residence and complication rate are the most frequently used outcome parameters. The patient-reported outcomes included activities of daily living and mobility scores. There is a need for generally agreed upon outcome measures to facilitate comparison of different care models.
Non-LTE, line-blanketed model atmospheres for late O- and early B-type stars
NASA Technical Reports Server (NTRS)
Grigsby, James A.; Morrison, Nancy D.; Anderson, Lawrence S.
1992-01-01
The use of non-LTE line-blanketed model atmospheres to analyze the spectra of hot stars is reported. The stars analyzed are members of clusters and associations, have spectral types in the range O9-B2 and luminosity classes in the range III-IV, have slow to moderate rotation, and are photometrically constant. Sampled line opacities of iron-group elements were incorporated in the radiative transfer solution; solar abundances were assumed. Good to excellent agreement is obtained between the computed profiles and essentially all the line profiles used to fix the model, and reliable stellar parameters are derived. The synthetic M II 5581 equivalent widths agree well with the observed ones at the low end of the temperature range studied, but, above 25,000 K, the synthetic line is generally stronger than the observed line. The behavior of the observed equivalent widths of N II, N III, C II and C III lines as a function of Teff is studied. Most of the lines show much scatter, with no consistent trend that could indicate abundance differences from star to star.
Consent process for US-based family reference DNA samples.
Katsanis, Sara H; Snyder, Lindsey; Arnholt, Kelly; Mundorff, Amy Z
2018-01-01
DNA collection from family members of the missing is a tenet for missing persons' and mass fatality investigations. Procedures for consenting family members are disparate, depending on the context supporting the reason for sample collection. While guidelines and best practices have been developed for handling mass fatalities and for identification of the missing, these guidelines do not address standard consent practices for living family members of potential victims. We examined the relevant U.S. laws, international guidelines and best practices, sampled consent forms currently used for DNA collection of family members, and drafted model language for a consent form to communicate the required and recommended information. We modeled the consent form on biobank consenting practices and tested the consent language among students and the general population for constructive feedback and readability. We also asked respondents to consider the options for DNA collection and either hypothetically agree or disagree. The model language presented here highlights information important to relay in consent processes and can serve as a foundation for future consent practices in mass fatalities and missing persons' investigations. Copyright © 2017 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Mei, Yang; Chen, Bo-Wei; Wei, Chen-Fu; Zheng, Wen-Chen
2016-09-01
The high-order perturbation formulas based on the two-mechanism model are employed to calculate the spin-Hamiltonian parameters (g factors gi and hyperfine structure constants Ai, where i=x, y, z) for two approximately rhombic W5+ centers in KTiOPO4 (KTP) crystal. In the model, both the widely-applied crystal-field (CF) mechanism concerning the interactions of CF excited states with the ground state and the generally-neglected charge-transfer (CT) mechanism concerning the interactions of CT excited states with the ground state are included. The calculated results agree with the experimental values, and the signs of constants Ai are suggested. The calculations indicate that (i) for the high valence state dn ions in crystals, the contributions to spin-Hamiltonian parameters should take into account both the CF and CT mechanisms and (ii) the large g-shifts |Δgi | (=|gi-ge |, where ge≈ 2.0023) for W5+ centers in crystals are due to the large spin-orbit parameter of free W5+ ion.
Matsuda, Yui
2017-05-01
The Latino population in the United States is quickly growing, and its unintended pregnancy rate is increasing. To decrease unintended pregnancies, couples must mutually agree on family planning. Communication between partners is one key factor identified in successful family planning for couples. Therefore, the purpose of this study was to examine sexual communication and its associations with sexual relationship power, general communication, and views on family planning. The Actor-Partner Interdependence Model was used to analyze dyadic influences of the chosen variables. Forty immigrant Latino couples were recruited from prenatal care clinics. The study results were grouped according to the three types of power structures: exhibition of men's traditional machismo values, exhibition of women's increased power in their relationships, and exhibition of men's and women's own empowerment with sexual communication. There was a negative association between men's views on family planning and women's sexual communication (exhibition of machismo values); a negative association between women's sexual relationship power and their partners' sexual communication (exhibition of women's increased power); and positive associations between men's and women's general communication and sexual communication (exhibition of men's and women's own empowerment). Dyadic influences of sexual communication and associated variables need to be incorporated into interventions to facilitate family planning for couples.
2009-06-12
strong indications that sappers may be operating in town tonight . Accordingly, I want your command on 10 maximum alert.‖ 25 General...Westmoreland, ―this is going to happen in the rest of the country tonight or tomorrow morning.‖ 4 The General agreed and petitioned President Thieu...kept 24-hour security on a dozen outlying buildings spread throughout the city including the Ambassador‘s residence. 8 They also provided VIP escorts
Unclassified Report on the President’s Surveillance Program
2009-07-10
for Intelligence Policy James Baker. Jay Bybee was OLC Assistant Attorney General from November 2001 through March 2003, and Yoo’s supervisor. Bybee ...Attorney General slots. Bybee said he was "enthusiastic" about Yoo and later agreed to Yoo’s request to be assigned to the "national security portfolio...34 because Y00 had more national security experience than any of the other OLC deputies. However, Bybee stated he was never read into the PSP and could
The behaviour of 39 pesticides in surface waters as a function of scale
Capel, P.D.; Larson, S.J.; Winterstein, T.A.
2001-01-01
A portion of applied pesticides runs off agricultural fields and is transported through surface waters. In this study, the behaviour of 39 pesticides is examined as a function of scale across 14 orders of magnitude from the field to the ocean. Data on pesticide loads in streams from two US Geological Survey programs were combined with literature data from field and watershed studies. The annual load as percent of use (LAPU) was quantified for each of the fields and watersheds and was used as the normalization factor across watersheds and compounds. The in-stream losses of each pesticide were estimated for a model stream with a 15 day travel time (similar in characteristics to the upper Mississippi River). These estimated in-stream losses agreed well with the observed changes in apparent LAPU values as a function of watershed area. In general, herbicides applied to the soil surface had the greatest LAPU values and minimal in-stream losses. Soil-incorporated herbicides had smaller LAPU values and substantial in-stream losses. Insecticides generally had LAPU values similar to the incorporated herbicides, but had more variation in their in-stream losses. On the basis of the LAPU values of the 39 pesticides as a function of watershed area, a generalized conceptual model of the movement of pesticides from the field to the ocean is suggested. The importance of considering both field runoff and in-stream losses is discussed in relation to interpreting monitoring data and making regulatory decisions.
Effects of temperature on embryonic development of lake herring (Coregonus artedii)
Colby, Peter J.; Brooke, L.T.
1973-01-01
Embryonic development of lake herring (Coregonus artedii) was observed in the laboratory at 13 constant temperatures from 0.0 to 12.1 C and in Pickerel Lake (Washtenaw County, Michigan) at natural temperature regimes. Rate of development during incubation was based on progression of the embryos through 20 identifiable stages. An equation was derived to predict development stage at constant temperatures, on the general assumption that development stage (DS) is a function of time (days, D) and temperature (T). The equation should also be useful in interpreting estimates from future regressions that include other environmental variables that affect egg development. A second regression model, derived primarily for fluctuating temperatures, related development rate for stage j (DRj), expressed as the reciprocal of time, to temperature (x). The generalized equation for a development stage is: DRj = abx cx2 dx3. In general, time required for embryos to reach each stage of development in Pickerel Lake agreed closely with the time predicted from this equation, derived from our laboratory observations. Hatching time was predicted within 1 day in 1969 and within 2 days in 1970. We used the equations derived with the second model to predict the effect of the superimposition of temperature increases of 1 and 2 C on the measured temperatures in Pickerel Lake. Conceivably, hatching dates could be affected sufficiently to jeopardize the first feeding of lake herring through loss of harmony between hatching date and seasonal food availability.