WorldWideScience
1

Predation and fragmentation portrayed in the statistical structure of prey time series  

UK PubMed Central (United Kingdom)

BackgroundStatistical autoregressive analyses of direct and delayed density dependence are widespread in ecological research. The models suggest that changes in ecological factors...Full Text Available

2

THE APPLICATION OF STATISTICS TO THE FLIGHT ...  

Science.gov (United States)

... Measuring Instruments ..... 7-18 7.4 Power Spectral Density Measurements of Random DaL. .... 7-19 7 ...

1961-12-01

3

Multiparametric Statistics  

CERN Document Server

Multiparametric Statistics

2007-01-01

4

The RooStats Project  

CERN Document Server

RooStats is a project to create advanced statistical tools required for the analysis of LHC data, with emphasis on discoveries, confidence intervals, and combined measurements. The idea is to provide the major statistical techniques as a set of C++ classes with coherent interfaces, which can be used on arbitrary model and datasets in a common way. The classes are built on top of RooFit, which provides a very convenient functionality for modeling the probability density functions or the likelihood functions, required as inputs for any statistical technique. Furthermore, RooFit provides the functionality for easily creating models, for analysis combination and for digital publication of the likelihood function and the data. We will present in detail the design and the implementation of the different statistical methods of RooStats. These include various classes for interval estimation ...

2010-01-01

5

Statistics at Square One  

CERN Document Server

Statistics at Square One

2009-01-01

6

Nonequilibrium statistical mechanics  

CERN Document Server

Nonequilibrium statistical mechanics

2001-01-01

7

Nuclear spectroscopy, ch. 8  

International Nuclear Information System (INIS)

Energy level schemes are derived from gamma spectroscopy of several medium-mass deformed nuclei by studying the decay or proton and #alpha# nuclear spectroscopic data. Some new isomeric studies are established among which is the 31 y "1"7"8Hf isomeric state for which Isup(#pi#), K was determined to be 16"+, 16. A four quasi-particle configuration was assigned to this state at 2447.5 +- 2.5 KeV. Atomic masses have been calculated from various measurements and, on the basis of mass formulae extrapolated to neighboring mass regions.

8

Asymmetric rotor model for decoupled bands in transitional odd-mass nuclei  

International Nuclear Information System (INIS)

The high-spin states in transitional odd-mass nuclei are studied in terms of an odd quasi-particle coupled to an asymmetric rotor with a variable moment of inertia (VMI). In order to take into account the VMI, the basis states are expanded in terms of the core eigenfunctions. Excitation energies, quadrupole moments, magnetic moments, B(E2) values and B(M1) values are calculated and compared with the experimental data for nuclei in Au and La regions. On comparison with other descriptions it is found that the treatment with VMI provides a more satisfactory explanation of the data. (Auth.).

9

A microscopic triaxial description of "1"8"7Ir, "1"8"7Os, "1"8"9Ir and "1"8"9Pt  

International Nuclear Information System (INIS)

A completely microscopic theory for "1"8"7Ir, "1"8"7Os, "1"8"9Ir and "1"8"9Pt is developed in terms of a quasi-particle coupled to the neighbouring even-even core. The calculated values of the positive parity states of "1"8"7Ir are given which agree fairly good with the experimental values. The values of the negative parity states of "1"8"7Ir are also given. (author).

10

Choice of distance from radiation source to tested object for gamma-absorption density measurer in divergent pencil of ray  

International Nuclear Information System (INIS)

Formulae are derived for estimation of the effect of gamma beam divergence on the value of systematic and statistical components of the errors of density measurement in production of structural materials and products also in the process of exploitation of building structures and constructions. Engineering technique for choice of the distance between radiation source and object under test is developed for absorption radioisotope densimeter operating by the scheme of geometry of divergent beam with amplitude compensation of backscattered radiation effect. The assessment of radioisotope densimeter efficiency providing the error of density measurement prescribed at design stage

11

Simulation of statistical {gamma}-spectra of highly excited rare earth nuclei  

Energy Technology Data Exchange (ETDEWEB)

The statistical {gamma}-spectra of highly excited even-even rare earth nuclei are simulated applying appropriate level density and strength function to a given nucleus. Hindrance effects due to K-conservation are taken into account. Simulations are compared to experimental data from the {sup 163}Dy({sup 3}He,{alpha}){sup 162}Dy and {sup 173}Yb({sup 3}He,{alpha}){sup 172}Yb reactions. The influence of the K quantum number at higher energies is discussed. 21 refs., 7 figs., 2 tabs.

1997-05-01

12

An effective method to estimate multidimensional Gaussian states  

CERN Document Server

A simple and efficient method for characterization of multidimensional Gaussian states is suggested and experimentally demonstrated. Our scheme shows analogies with tomography of finite dimensional quantum states, with the covariance matrix playing the role of the density matrix and homodyne detection providing Stern-Gerlach-like projections. The major difference stems from a different character of relevant noises: while the statistics of Stern-Gerlach-like measurements is governed by binomial statistics, the detection of quadrature variances correspond to chi-square statistics. For Gaussian and near Gaussian states the suggested method provides, compared to standard tomography techniques, more stable and reliable reconstructions. In addition, by putting together reconstruction methods for Gaussian and arbitrary states, we obtain a tool to detect the non-Gaussian character of optical signals.

2009-01-01

13

Phase Information and the Evolution of Cosmological Density Perturbations  

CERN Document Server

The Fourier transform of cosmological density perturbations can be represented in terms of amplitudes and phases for each Fourier mode. We investigate the phase evolution of these modes using a mixture of analytical and numerical techniques. Using a toy model of one-dimensional perturbations evolving under the Zel'dovich approximation as an initial motivation, we develop a statistic that quantifies the information content of the distribution of phases. Using numerical simulations beginning with more realistic Gaussian random-phase initial conditions, we show that the information content of the phases grows from zero in the initial conditions, first slowly and then rapidly when structures become non-linear. This growth of phase information can be expressed in terms of an effective entropy: Gaussian initial conditions are a maximum entropy realisation of the initial power spectrum, gravitational evolution decreases the phase entropy. We show that ...

2000-01-01

14

Partial width fluctuation method of determining nuclear level density  

Energy Technology Data Exchange (ETDEWEB)

A new method of determining the nuclear level density is presented. This method is based on the statistical analysis of the partial width fluctuations appearing in an excitation function of the radiative proton capture. The method was applied in the case of the /sup 88/Sr(p,..gamma..sub(..omega..))/sup 89/Y and /sup 89/Y(p,..gamma..sub(..omega..))/sup 90/Zr reactions. The density of levels with spin I/sup -/ in /sup 90/Zr and the densities of levels with spins 1/2/sup +/ and 3/2/sup +/ in /sup 89/Y at excitation energies from 10.9 to 11.6 MeV and from 9.3 to 10.8 MeV respectively, were determined with an uncertainty of about 35%.

1982-04-12

15

Statistical modelling for social researchers principles and practice  

CERN Document Server

Statistical modelling for social researchers

2008-01-01

16

Statistical Analysis of Designed Experiments  

CERN Document Server

Statistical Analysis of Designed Experiments

2010-01-01

17

Essential Mathematics and Statistics for Science  

CERN Document Server

Essential Mathematics and Statistics for Science

2009-01-01

18
19

Applied Statistics for Civil and Environmental Engineers  

CERN Document Server

Applied Statistics for Civil and Environmental Engineers

2009-01-01

20

Stability of model recycled mixed plastic waste compatibilised with a cooperative compatibilisation system  

British Library Electronic Table of Contents (United Kingdom)

The effect of the degree of degradation of the components of a model municipal plastic waste (a mixture of low-density polyethylene, high-density polyethylene, polypropylene and high-impact polystyrene) on the toughness and stability of recyclates compatibilised with a cooperative compatibilisation system (a mixture of ethylene-propylene statistical and styrene-butadiene block copolymers with a secondary amine-based stabiliser) was studied. It was shown that good impact strength was achieved for recyclates having components with a low or medium degree of degradation. Mechanical properties of recyclates having the components with a high degree of degradation are deteriorated. The addition of the cooperative compatibilisation system leads to a higher thermo-oxidative stability of recyclates ...

2011-01-01

21

A review of the probabilistic aspects of localized corrosion  

Energy Technology Data Exchange (ETDEWEB)

Localized corrosion has a stochastic character by nature. This character leads to an observed random behavior: fluctuations of the free potential, fluctuations of the current when a constant potential is maintained. This random signal, which is similar to an electric noise, can be analyzed either in the time domain by counting the events or in the frequency domain by measuring the power spectral density of the electrochemical noise. The experimental techniques developed for investigating the localized corrosion on the probabilistic point of view, i.e., statistical counting and power spectral density measurements, are discussed. Then the experimental results reported in the literature are reviewed in order to see what kind of parameters are accessible and how they can be related to the localized corrosion processes.

1990-04-01

22

Low-lying states of {sup 109}Sn from the {sup 106}Cd({alpha},n{gamma}) reaction  

Energy Technology Data Exchange (ETDEWEB)

Measurements of {gamma}-ray, {gamma}{gamma}-coincidence and internal conversion electron spectra from the {sup 106}Cd({alpha},n{gamma}){sup 109}Sn reaction were carried out at 15-20 MeV {alpha}-particle bombarding energies with Ge(HP) {gamma}-ray and superconducting magnetic lens plus Si(Li) electron spectrometers. The energies, relative intensities, internal conversion coefficients and coincidence relations of the {sup 109}Sn transitions were determined, and a more complete, consistent level scheme has been deduced. Spin and parity values have been determined from the internal conversion coefficients, the bombarding-energy dependence of the side-feeding intensities of the states and the available {gamma}-ray angular distribution data. The level scheme was interpreted in the framework of the quasi-particle shell model.

1999-02-01

23

The market efficiency in the stock markets  

CERN Document Server

We study the temporal evolution of the market efficiency in the stock markets using the complexity, entropy density, standard deviation, autocorrelation function, and probability distribution of the log return for Standard and Poor's 500 (S&P 500), Nikkei stock average index, and Korean composition stock price index (KOSPI). Based on the microscopic spin model, we also find that these statistical quantities in stock markets depend on the market efficiency.

2007-01-01

24

Glacial geology of the West Tensleep Drainage Basin, Bighorn Mountains, Wyoming  

Energy Technology Data Exchange (ETDEWEB)

The glacial deposits of the West Tensleep Basin in the Bighorn Mountains of Wyoming are mapped and a relative chromology established. The deposits are correlated with the regional model as defined in the Wind River Mountains. A statistical analysis is performed on the density and weathering characteristics of the surficial boulders to determine their validity as indicators of relative age. (ACR)

1980-08-01

25

Diagnostic capability of digital radiography of the chest using scanning laser stimulated luminescence  

Energy Technology Data Exchange (ETDEWEB)

Diagnostic capability of Fuji Computed Radiography (FCR) of the chest was compared to the conventional radiography (CoR) using regular film-screen system. FCR utilizers imaging plates of scanning laser stimulated luminescence. Visibility of 14 structures of the chest radiography was evaluated by 3 radiologists in 100 pairs of FCR and CoR which were taken at the same time with the same exposure factors. FCR was superior to CoR especially in observation of the mediastinum and areas behind the heart and diaphragm. The minor fissure was better seen on CoR. Superiority of FCR to CoR was thought to be mainly due to the processed image of FCR, and the so-called normal image of FCR had little diagnostic advantage. Simulated abnormal densities: nodular, alveolar, and interstitial densities with a chest phantom, were made, and detectability of alteration of these densities on FCR and CoR was evaluated by 19 radiologists, using ROC ...

1989-02-01

26

Diagnostic capability of digital radiography of the chest using scanning laser stimulated luminescence  

International Nuclear Information System (INIS)

Diagnostic capability of Fuji Computed Radiography (FCR) of the chest was compared to the conventional radiography (CoR) using regular film-screen system. FCR utilizers imaging plates of scanning laser stimulated luminescence. Visibility of 14 structures of the chest radiography was evaluated by 3 radiologists in 100 pairs of FCR and CoR which were taken at the same time with the same exposure factors. FCR was superior to CoR especially in observation of the mediastinum and areas behind the heart and diaphragm. The minor fissure was better seen on CoR. Superiority of FCR to CoR was thought to be mainly due to the processed image of FCR, and the so-called normal image of FCR had little diagnostic advantage. Simulated abnormal densities: nodular, alveolar, and interstitial densities with a chest phantom, were made, and detectability of alteration of these densities on FCR and CoR was evaluated by 19 radiologists, using ROC ...

1989-01-01

27

Quantitative CT assessment of proximal femoral bone density. An experimental study concerning its correlation to breaking load for femoral neck fractures  

International Nuclear Information System (INIS)

Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm"3 volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone ...

28

Searching for the non-gaussian signature of the CMB secondary anisotropies  

CERN Document Server

In a first paper (Forni & Aghanim 1999), we developed several statistical discriminators to test the non-gaussian nature of a signal. These tests are based on the study of the coefficients in a wavelet decomposition basis. In this paper, we apply them in a cosmological context, to the study of the nature of the Cosmic Microwave Background (CMB) anisotropies. The latter represent the superposition of primary anisotropy imprints of the initial density perturbations and secondary ones due to photon interactions after recombination. In an inflationary scenario (standard Cold Dark Matter) with gaussian distributed fluctuations, we study the statistical signature of the secondary effects. More specifically, we investigate the dominant effects arising from the Compton scattering of CMB photons in ionised regions of the Universe: the Sunyaev-Zel'dovich effect of galaxy clusters and the effects of a spatially inhomogeneous ...

1999-01-01

29

Non-Gaussian gravitational clustering field statistics  

CERN Document Server

In this work we investigate the multivariate statistical description of the matter distribution in the nonlinear regime. We introduce the multivariate Edgeworth expansion of the lognormal distribution to model the cosmological matter field. Such a technique could be useful to generate and reconstruct three-dimensional nonlinear cosmological density fields with the information of higher order correlation functions. We explicitly calculate the expansion up to third order in perturbation theory making use of the multivariate Hermite polynomials up to sixth order. The probability distribution function for the matter field includes at this level the two-point, the three-point and the four-point correlation functions. We use the hierarchical model to formulate the higher order correlation functions based on combinations of the two-point correlation function. This permits us to find compact expressions for the skewness and kurtosis terms of the ...

2010-01-01

30

Concerning the statistics of cosmic magnetism  

CERN Document Server

Magnetic fields appear to be a generic feature of the early universe and are a natural source of secondary CMB non-Gaussianity. In recent years the statistical nature of the stresses of a primordial magnetic field has been well studied. In this paper we confirm and extend these studies at one- and two-point level, and present analytical results for a wide range of power-law spectra. We also consider two non-power law cases of interest: a blue spectrum with an extended damping tail on small scales, which could be generated by the non-linear mixing of density and vorticity; and a red spectrum with a damping tail on large scales. We then briefly consider the CMB impacts that result from such fields. While this paper focuses on the one- and two-point moments, the techniques we employ are designed to ease the analysis of the full bispectra induced by primordial magnetic fields.

2010-01-01

31

A Cross-National Analysis of How Economic Inequality Predicts Biodiversity Loss  

British Library Electronic Table of Contents (United Kingdom)

Abstract: We used socioeconomic models that included economic inequality to predict biodiversity loss, measured as the proportion of threatened plant and vertebrate species, across 50 countries. Our main goal was to evaluate whether economic inequality, measured as the Gini index of income distribution, improved the explanatory power of our statistical models. We compared four models that included the following: only population density, economic footprint (i.e., the size of the economy relative to the country area), economic footprint and income inequality (Gini index), and an index of environmental governance. We also tested the environmental Kuznets curve hypothesis, but it was not supported by the data. Statistical comparisons of the models revealed that the model including both economi...

2009-01-01

32

Computational AstroStatistics Fast and Efficient Tools for Analysing Huge Astronomical Data Sources  

CERN Document Server

I present here a review of past and present multi-disciplinary research of the Pittsburgh Computational AstroStatistics (PiCA) group. This group is dedicated to developing fast and efficient statistical algorithms for analysing huge astronomical data sources. I begin with a short review of multi-resolutional kd-trees which are the building blocks for many of our algorithms. For example, quick range queries and fast n-point correlation functions. I will present new results from the use of Mixture Models (Connolly et al. 2000) in density estimation of multi-color data from the Sloan Digital Sky Survey (SDSS). Specifically, the selection of quasars and the automated identification of X-ray sources. I will also present a brief overview of the False Discovery Rate (FDR) procedure (Miller et al. 2001a) and show how it has been used in the detection of ``Baryon Wiggles'' in the local galaxy power spectrum and source identification ...

2001-01-01

34

Enhancement of bioleaching of a spent Ni/Mo hydroprocessing catalyst by Penicillium simplicissimum  

British Library Electronic Table of Contents (United Kingdom)

Statistically based experimental designs were applied to screen and optimize the bioleaching of spent hydrocracking catalyst by Penicillium simplicissimum. Eleven factors were examined for their significance on bioleaching using a Plackett-Burman factorial design. Four significant variables (pulp density, sucrose, NaNO"3, and yeast extract concentrations) were selected for the optimization studies. The combined effect of these variables on metal bioleaching was studied using a central composite design (CCD). Second-order polynomials were established to identify the relationship between the recovery percent of the metals and the four significant variables. The optimal values of the variables for maximum metals bioleaching were as follows: pulp density (4.0%, w/v), sucrose (90g/L), NaNO"3 (2...

2011-01-01

35

A statistical evaluation of recent SSC conductors produced at IGC/ASI  

International Nuclear Information System (INIS)

One of the requirements for uniform field quality in the SSC dipole magnets is the consistency in the superconducting strand characteristics from start to finish to the production phase. As full scale production of strand and cable approaches, the consistency in performance of the early batches of conductor needs to be examined. A number of 300 mm billets have been manufactured at IGC with tight process controls. The performance of the final conductor in terms of piece lengths, current density, Cu/Sc ratio and wire diameter has been evaluated. The data are analyzed in order to understand the variations that are related to the conductor design and processing. In this paper the current density of the strand is examined over the length of the billet to determine inherent variability in the Nb/Ti alloy itself.

1990-09-24

36

Theory of melting and crystallization  

Energy Technology Data Exchange (ETDEWEB)

A consistent statistical theory of the crystal-liquid phase transition is developed, being based on a method which takes into account liquidlike fluctuations in crystals and solidlike clusters in liquids. It is shown that degenerate fluidlike droplets have a finite number density at zero temperature, while nondegenerate fluctuations disappear when the temperature goes to zero. The existence of a melting point is proved. This method, which takes into consideration the heterophase fluctuations, provides the possibility of describing metastable states such as a supercooled liquid or an overheated crystal. Conditions for the existence of metastable states are found. The liquid-glass transition can also be described by the method presented here.

1985-07-01

37

Optimization of inspection and replacement period by using Bayesian statistics  

International Nuclear Information System (INIS)

This study describes the formulations to optimize the time interval of inspections and/or replacements of equipment/parts taking into account the probability density functions (PDF) for failure rates and parameters of failure distribution functions (FDF) and evaluates the optimized results of these time intervals using our formulations by comparing with those using only representative values of failure rates and the parameters of FDF instead of using these PDFs. The PDFs are obtained with Bayesian method and the representative values are obtained with likelihood estimation method. However, any significant difference is not observed between both optimized results within our preliminary calculations. (author)

2006-07-01

38

Experimental generation of non-Kolmogorov turbulence using a liquid crystal spatial light modulator  

Science.gov (United States)

Several experiments showed that the classical Kolmogorov power spectral density of the refractive-index sometimes does not properly describe the statistics of the atmosphere. In this paper we show an experimental testbed able to generate non-classical Kolmogorov turbulence by using a liquid crystal spatial light modulator. The testbed is used at Naval Postgraduate School for laboratory investigation of laser beam propagation in maritime environment where a power law different from classical Kolmogorov, 11/ 3, could be present. Applications of this testbed are ship to-ship free space optical communication, imaging and high energy laser weapons.

2011-09-01

39

Entangled quantum currents in distant mesoscopic Josephson junctions  

Energy Technology Data Exchange (ETDEWEB)

Two mesoscopic SQUID rings which are far from each other are considered. A source of two-mode nonclassical microwaves irradiates the two rings with correlated photons. The Josephson currents are in this case quantum mechanical operators, and their expectation values with respect to the density matrix of the microwaves yield the experimentally observed currents. Classically correlated (separable) and quantum mechanically correlated (entangled) microwaves are considered, and their effect on the Josephson currents is quantified. Results for two different examples that involve microwaves in number states and coherent states are derived. It is shown that the quantum statistics of the tunnelling electron pairs through the Josephson junctions in the two rings are correlated.

2004-12-22

40

Statistical Inference, Econometric Analysis and Matrix Algebra  

CERN Document Server

Statistical Inference, Econometric Analysis and Matrix Algebra

2008-01-01

41

Power law correlations in galaxy distribution and finite volume effects from the Sloan Digital Sky Survey Data Release Four  

CERN Document Server

We discuss the estimation of galaxy correlation properties in several volume limited samples, in different sky regions, obtained from the Fourth Data Release of the Sloan Digital Sky Survey. The small scale properties are characterized through the determination of the nearest neighbor probability distribution. By using a very conservative statistical analysis, in the range of scales [0.5,~30] Mpc/h we detect power-law correlations in the conditional density in redshift space, with an exponent \\gamma=1.0 \\pm 0.1. This behavior is stable in all different samples we considered thus it does not depend on galaxy luminosity. In the range of scales [~30,~100] Mpc/h we find evidences for systematic unaveraged fluctuations and we discuss in detail the problems induced by finite volume effects on the determination of the conditional density. We conclude that in such range of scales there is an evidence for a smaller power-law index ...

2006-01-01

42

Nuclear-level density of {sup 113}Sn, {sup 114}Sn, {sup 115}Sn, and {sup 116}Sn from an analysis of neutron spectra in the reactions {sup 115}In(p,xn), {sup 115}In(d,xn), and {sup 113}Cd({alpha},xn)  

Energy Technology Data Exchange (ETDEWEB)

The differential cross sections for neutron emission in the reactions {sup 115}In(p,xn), {sup 115}In(d,xn), and {sup 113}Cd({alpha},xn) are measured and analyzed for proton energies 11.2 and 22.2 MeV, deuteron energy 22.3 MeV, and {alpha}-particle energies 26.8 and 45.2 MeV, respectively. The parameters of the nuclear-level density in the Fermi-gas model with negative energy shift are determined for the {sup 113}Sn, {sup 114}Sn, {sup 115}Sn, and {sup 116}Sn nuclei over a wide range of excitation energies. Analysis is performed in a statistical model that uses the Hauser-Feshbach mathematical formalism to describe multistage processes. It is shown that, as excitation energy increases, the parameter of the level density for these nuclei first decreases (this behavior is consistent with the predictions of the generalized model of a superfluid nucleus) and then increases (this points to the destruction of the nuclear-shell ...

1995-02-01

43

Sound transmission loss of composite sandwich panels  

Science.gov (United States)

Light composite sandwich panels are increasingly used in automobiles, ships and aircraft, because of the advantages they offer of high strength-to-weight ratios. However, the acoustical properties of these light and stiff structures can be less desirable than those of equivalent metal panels. These undesirable properties can lead to high interior noise levels. A number of researchers have studied the acoustical properties of honeycomb and foam sandwich panels. Not much work, however, has been carried out on foam-filled honeycomb sandwich panels. In this dissertation, governing equations for the forced vibration of asymmetric sandwich panels are developed. An analytical expression for modal densities of symmetric sandwich panels is derived from a sixth-order governing equation. A boundary element analysis model for the sound transmission loss of symmetric sandwich panels is proposed. Measurements of the modal density, total loss factor, ...

2009-01-01

44

Spectroscopy of "8"8Sr with the "8"7Sr(n,#gamma#) and "8"7Sr(d,p) reactions  

International Nuclear Information System (INIS)

The #gamma#-ray spectrum emitted after thermal neutron capture in "8"7Sr was studied at the ILL high flux reactor with pair- and intrinsic Ge-spectrometers. 661 transitions were assigned to the reaction "8"7Sr(n,#gamma#)"8"8Sr and 205 of them were placed into a "8"8Sr level scheme of 47 levels. This represents 88% of the observed intensity. The level energies were determined with a precision of better than 22 ppm; the neutron binding energy was determined as 11 112.69 (22) keV. To aid the analysis high resolution particle spectra of the reaction "8"7Sr(d,p)"8"8Sr were measured at 20 MeV deuteron energy with the Munich Q3D spectrometer. 85 states were observed with this reaction. The data helped to establish newly found levels and to differentiate between primary and secondary transitions in the (n,#gamma#) data. The observed level densities and primary transition strengths are compared with statistical model predictions and ...

45

On the application of Allan variance method for Ring Laser Gyro performance characterization  

Energy Technology Data Exchange (ETDEWEB)

This report describes the method of Allan variance and its application to the characterization of a Ring Laser Gyro`s (RLG) performance. Allan variance, a time domain analysis technique, is an accepted IEEE standard for gyro specifications. The method was initially developed by David Allan of the National Bureau of Standards to quantify the error statistics of a Cesium beam frequency standard employed as the US Frequency Standards in 1960`s. The method can, in general, be applied to analyze the error characteristics of any precision measurement instrument. The key attribute of the method is that it allows for a finer, easier characterization and identification of error sources and their contribution to the overall noise statistics. This report presents an overview of the method, explains the relationship between Allan variance and power spectral density distribution of underlying noise sources, describes the batch and ...

1993-10-15

46

Deformation study of separator pellets for thermal batteries  

Energy Technology Data Exchange (ETDEWEB)

The deformation characteristics of pellets of electrolyte-binder (EB) mixes based on MgO were measured under simulated, thermal-battery conditions. Measurements (using a statistically designed experimental strategy) were made as a function of applied pressure, temperature, and percentage of theoretical density for four molten-salt electrolytes at two levels of MgO. The EB mixes are used as separators in Li-alloy thermal batteries. The electrolytes included LiCl-KCI eutectic, LiCl-LiBr-KBr eutectic, LiBr-KBr-LiF eutectic, and a LiCl-LiBr-LiF electrolyte with a minimum-melting composition. The melting points ranged from 313 C to 436 C. The experimental data were used to develop statistical models that approximate the deformation behavior of pellets of the various EB mixes over the range of experimental conditions we examined. This report, discusses the importance of the deformation response surfaces to thermal-battery design.

1995-05-01

47

A statistically-selected Chandra sample of 20 galaxy clusters -- II. Gas properties and cool-core/non-cool core bimodality  

CERN Document Server

We investigate the thermodynamic and chemical structure of the intracluster medium (ICM) across a statistical sample of 20 galaxy clusters analysed with the Chandra X-ray satellite. In particular, we focus on the scaling properties of the gas density, metallicity and entropy and the comparison between clusters with and without cool cores (CCs). We find marked differences between the two categories except for the gas metallicity, which declines strongly with radius for all clusters (Z ~ r^{-0.31}), outside ~0.02 r500. The scaling of gas entropy is non-self-similar and we find clear evidence of bimodality in the distribution of logarithmic slopes of the entropy profiles. With only one exception, the steeper sloped entropy profiles are found in CC clusters whereas the flatter slope population are all non-CC clusters. We explore the role of thermal conduction in stabilizing the ICM and conclude that this mechanism alone is sufficient to balance ...

2009-01-01

48

Weak values under uncertain conditions  

British Library Electronic Table of Contents (United Kingdom)

We analyze the average of weak values over statistical ensembles of pre- and post-selected states. The protocol of weak values, proposed by Aharonov et al. [Phys. Rev. Lett. 60 (1988) 1351], is the result of a weak measurement conditional on the outcome of a subsequent strong (projective) measurement. Weak values can be beyond the range of eigenvalues of the measured observable and, in general, can be complex numbers. We show that averaging over ensembles of pre- and post-selected states reduces the weak value within the range of eigenvalues of Formula Not Shown . We further show that the averaged result expressed in terms of pre- and post-selected density matrices, allows us to include the effect of decoherence.

2010-01-01

49

Topological Analysis of Large-scale Biomedical Terminology Structures  

British Library Electronic Table of Contents (United Kingdom)

ObjectiveTo characterize global structural features of large-scale biomedical terminologies using currently emerging statistical approaches.DesignGiven rapid growth of terminologies, this research was designed to address scalability. We selected 16 terminologies covering a variety of domains from the UMLS Metathesaurus, a collection of terminological systems. Each was modeled as a network in which nodes were atomic concepts and links were relationships asserted by the source vocabulary. For comparison against each terminology we created three random networks of equivalent size and density.MeasurementsAverage node degree, node degree distribution, clustering coefficient, average path length.ResultsEight of 16 terminologies exhibited the small-world characteristics of a short average path le...

2007-01-01

50

The transition of metallic crystals nanostructure into the nanostructure of metallic liquids  

International Nuclear Information System (INIS)

The evolution of metallic substance atomic structure is studied on temperature variation including crystal heating up to melting points, a crystal- liquid phase transition and initiation of a high-density liquid specific structure. It is marked that heat induced changes of simple metal structure can be described as changes around a natural elementary cell which is common for both a crystal and a liquid and consists of a central atom and Z_1 atoms of the first coordination sphere. On this basis the vacancy model of melting is verified. Concentrations of melting vacancies are determined by coordination numbers in the form of Z_1/(1+Z_1)"2 which are the same for both a crystal and a natural elementary cell. The size of natural elementary cells is in an agreement with that of the coordination sphere featured in the liquid and phase transition statistical theory. Calculated data are given for a number of metals, Cs, Eu, Ni, V included

51

Study on regional production and economy of cobia Rachycentron canadum commercial cage culture  

British Library Electronic Table of Contents (United Kingdom)

In recent years, cobia has become an emerging farmed species in Asia due to its quick growth and high economic value. This study collects biological and economic data affecting the economic performance of cobia farming in three countries, namely Taiwan, China, and Vietnam. The data are collected by questionnaire sampling and analyzed by multivariate statistical analysis in order to compare the key factors affecting the production and economy of cobia farming in these three countries. The results show that Taiwan, China, and Vietnam have significant differences in input intensities and profitability. China has the highest input intensity (3372.42?TWD/m3), as its high stocking density increases feed input. Taiwan has the highest unit input cost (103.44?TWD/kg), as the high quality of the pro...

2011-01-01

52

Spherical redshift distortions  

CERN Document Server

Peculiar velocities induce apparent line of sight displacements of galaxies in redshift space, distorting the pattern of clustering in the radial versus transverse directions. On large scales, the amplitude of the distortion yields a measure of the dimensionless linear growth rate \\ff of fluctuations, which is related to the cosmological density \\Omega and the linear bias factor b in linearly biassed standard cosmology by \\ff \\approx \\Omega^{0.6} /b. To make the maximum statistical use of the data in a wide angle redshift survey, and for the greatest accuracy, the spherical character of the distortion needs to be treated properly, rather than in the simpler plane parallel approximation. In the linear regime, the redshift space correlation function is described by a spherical distortion operator acting on the true correlation function. It is pointed out here that there exists an operator, which is essentially the logarithmic derivative with ...

1995-01-01

53

Kolmogoroff constants at the 1976 ITCE  

Energy Technology Data Exchange (ETDEWEB)

The high-frequency data from 12 sensors at the ITCE 1976 are analyzed to determine the Kolmogoroff constants for velocity, temperature and humidity fluctuations, ..cap alpha../sub u/, ..cap alpha../sub T/, and ..cap alpha../sub q/. The occurrence of aliasing in the spectral analysis in some cases together with the limited response of some sensors at the higher frequencies introduces some uncertainties into the analysis. The Soviet sonic anemometer, fine-wire thermometer and infrared hygrometer and the Australian infrared hygrometer provide the best information, namely that: ..cap alpha../sub u/ = 0.59 +/- 0.01, ..cap alpha../sub T/ = 0.68 +/- 0.02, ..cap alpha../sub q/ = 0.76 +/- 0.03, where the errors quoted refer solely to statistical errors. The other instruments provide general support to these values. The technique of using spectral density measurements to determine eddy fluxes is illustrated.

1982-01-01

54

Analysis of heterogeneous cell populations: A density-based modeling and identification framework  

British Library Electronic Table of Contents (United Kingdom)

Abstract: In many biological processes heterogeneity within clonal cell populations is an important issue. One of the most striking examples is a population of cancer cells in which after a common, identical death signal some cells die whereas others survive. The reason for this heterogeneity is intrinsic and extrinsic noise. In this paper we present a mechanistic multi-scale modeling framework for cell populations, in which the dynamics of every individual cell is captured by a parameter dependent stochastic differential equation (SDE). Heterogeneity among individual cells is accounted for by differences in parameter values, modeling extrinsic influences. Based on the statistical properties of the extrinsic noise and the SDE model for the individual cell, a partial differential equation (...

2011-01-01

58

OFFICE OF NEW DRUGS OFFICE OF PHARMACOEPIDEMIOLOGY AND STATISTICAL ...  

Science.gov (United States)

... The pharmacologist/toxicologist and the statistician will jointly determine if a statistical review is needed and when the review should be done. ...

59

Improved Mechanical Properties and Ozone Resistance of ...  

Science.gov (United States)

... 31 5.4 FACTORIAL DESIGN STATISTICAL ANALYSIS..... ... resistance. o Factorial design statistical analysis gave the ...

1991-08-01

60

Study of in-medium $\\omega$ meson properties in Ap, pA and AA collisions  

CERN Document Server

We propose to investigate the in-medium properties of vector $\\omega$ mesons at the normal nuclear density in Ap(pA) collisions and at higher density in AA collisions at the ITEP accelerator facility TWAC. Using of the inverse Ap kinematics will permit us to study the $\\omega$ meson production in a wide momentum interval included the not yet explored range of small meson momenta relative to the projectile nuclei where the mass modification effect in nuclear matter is expected to be the strongest. Momentum dependence of the in-medium $\\omega$ meson width will be studied in the traditional pA kinematics. We intend to use the electromagnetic calorimeter for reconstruction of the $\\omega$ meson invariant mass by detecting photons from the $\\omega \\to \\pi^{0}\\gamma \\to 3\\gamma$ decay. The model calculations and simulations with RQMD generator show feasibility of the proposed experiment. Available now intensity of the ion beams provides a ...

2008-01-01

61

Enhancing the capabilities of LIGO time-frequency plane searches through clustering  

CERN Document Server

One class of gravitational wave signals LIGO is searching for consists of short duration bursts of unknown waveforms. Potential sources include core collapse supernovae, gamma ray burst progenitors, and the merger of binary black holes or neutron stars. We present a density-based clustering algorithm to improve the performance of time-frequency searches for the such gravitational-wave bursts when they are extended in time and/or frequency. We have implemented this algorithm as an extension to the QPipeline search for bursts, which currently determines the statistical significance of events based solely on the peak significance observed in minimum uncertainty regions of the time-frequency plane. Density based clustering improves the performance of such a search by considering the aggregate significance of arbitrarily shaped regions in the time-frequency plane and rejecting the isolated minimum uncertainty features expected ...

2009-01-01

62

Cf-source-driven neutron-noise measurements of subcriticality for a 4. 95 wt% /sup 235/U-enriched uranyl fluoride solution cylinder  

Energy Technology Data Exchange (ETDEWEB)

A method for determining the reactivity of subcritical systems of fissile material, using neutron-noise power spectral density measurements in conjunction with a /sup 252/Cf source, has been tested in experiments with an aqueous solution containing uranium fluoride (4.95 wt% /sup 235/U). The kappasub(eff)-values obtained from the ratio of spectral densities G*/sub 12/G/sub 13//G/sub 11/G/sub 23/ agreed with those from break-frequency noise analysis and with bias-corrected transport theory calculations within the statistical uncertainty of the measurements. Corrections for the effects of spatial modes and source-detector locations appear to be well-understood, since measurements for a variety of source-detector positions resulted in essentially the same kappasub(eff)-values. Modal correction factors were such that ignoring them would result in higher values of kappasub(eff) than actually occur. The measurements have ...

1986-01-01

63

Benchmarks and models for 1-D radiation transport in stochastic participating media  

Energy Technology Data Exchange (ETDEWEB)

Benchmark calculations for radiation transport coupled to a material temperature equation in a 1-D slab and 1-D spherical geometry binary random media are presented. The mixing statistics are taken to be homogeneous Markov statistics in the 1-D slab but only approximately Markov statistics in the 1-D sphere. The material chunk sizes are described by Poisson distribution functions. The material opacities are first taken to be constant and then allowed to vary as a strong function of material temperature. Benchmark values and variances for time evolution of the ensemble average of material temperature energy density and radiation transmission are computed via a Monte Carlo type method. These benchmarks are used as a basis for comparison with three other approximate methods of solution. One of these approximate methods is simple atomic mix. The second approximate model is an adaptation of what is commonly ...

2000-08-21

64

Stochastic analysis of contaminant transport: One-dimensional non-reactive and reactive cases  

Energy Technology Data Exchange (ETDEWEB)

A reliability approach for probabilistic modeling of one-dimensional non-reactive and reactive transport in porous media provides two important quantitative results: (1) an estimate of the probability that dimensionless concentration equals or exceeds some specified level and, (2) the sensitivity of the probabilistic outcome to likely changes in each uncertain variable. The reliability approach is particularly attractive because it can incorporate various marginal probability density functions (PDF) for any of the uncertain variables. In this work uncertain variables include: groundwater flow velocity, diffusion coefficient, dispersivity, distribution coefficient, porosity and bulk density. The primary objective is to examine how the probabilistic outcome is influenced by choice of marginal PDF, correlation and magnitude of uncertainty for the variables. Because little information exists concerning the statistical ...

1990-12-03

65

Steepest changes of a probability-based cost function for delineation of mammographic masses: A validation study  

International Nuclear Information System (INIS)

Our purpose in this work was to develop an automatic boundary detection method for mammographic masses and to rigorously test this method via statistical analysis. The segmentation method utilized a steepest change analysis technique for determining the mass boundaries based on a composed probability density cost function. Previous investigators have shown that this function can be utilized to determine the border of the mass body. We have further analyzed this method and have discovered that the steepest changes in this function can produce mass delineations that include extended projections. The method was tested on 124 digitized mammograms selected from the University of South Florida's Digital Database for Screening Mammography (DDSM). The segmentation results were validated using overlap, accuracy, sensitivity, and specificity statistics, where the gold standards were manual traces provided by two expert radiologists. ...

2004-10-01

66

Spectroscopy of /sup 87,88,89/Sr with (n,. gamma. ) and (d,p) reactions  

Science.gov (United States)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at /sup 88/Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in /sup 87/Sr and /sup 89/Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic.) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,..gamma..) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to /sup 88/Sr(d,t)/sup 87/Sr and 24 keV neutron capture in /sup ...

1988-01-01

67

Spectroscopy of /sup 87,88,89/Sr with (n,#gamma#) and (d,p) reactions  

International Nuclear Information System (INIS)

Over the recent years the nuclear structure around the N = 50 shell closure, which is very pronounced in the strontium and zirconium isotopes, has been the subject of extensive experimental and theoretical work. On the proton side Z = 38 and Z = 40 provide fairly closed sub-shells. In the strontium isotopes the lg/sub 9/2/ neutron shell is closed at "8"8Sr, supplying relatively pure neutron-hole and neutron-particle states with large spectroscopic factors in "8"7Sr and "8"9Sr, as well as core-coupled states. The mass region is thus ideally suited to examine the transition from a correlated to an uncorrelated (chaotic?) excitational behavior. These two types are characterized e.g. by the density of excited states, the transition strengths, and the spectroscopic factors observed in transfer reactions. We conducted (n,#gamma#) and (d,p) reactions leading to /sup 87,88,89/Sr in addition to "8"8Sr(d,t)"8"7Sr and 24 keV neutron capture in "8"8Sr. The vast amounts of data ...

1988-04-24

68

Monte Carlo simulation and dosimetric verification of radiotherapy beam modifiers  

International Nuclear Information System (INIS)

Monte Carlo simulation of beam modifiers such as physical wedges and compensating filters has been performed with a rectilinear voxel geometry module. A modified version of the EGS4/DOSXYZ code has been developed for this purpose. The new implementations have been validated against the BEAM Monte Carlo code using its standard component modules (CMs) in several geometrical conditions. No significant disagreements were found within the statistical errors of 0.5% for photons and 2% for electrons. The clinical applicability and flexibility of the new version of the code has been assessed through an extensive verification versus dosimetric data. Both Varian multi-leaf collimator (MLC) wedges and standard wedges have been simulated and compared against experiments for 6 MV photon beams and different field sizes. Good agreement was found between calculated and measured depth doses and lateral dose profiles along both wedged and unwedged directions for different depths and ...

2001-11-01

69

Combined power generation with wind and ocean waves  

Energy Technology Data Exchange (ETDEWEB)

It is often advantageous to generate power with combinations of wind and ocean waves. In fact ocean waves, their generation, propagation, dissipation are directly related to wind velocity and its duration oven the sea. In this paper an attempt has been made to demonstrate statistically to present some advantages with combined wind and ocean wave power generation. Even though many conceptual techniques and methods are possible to harness combined power generation, it is important to test feasibility of combined output as well as individual outputs mathematically. One of the major advantages of combined wind and wave power generation is to improve probability of continuous power supply (it minimises the interruptions and compensates power fluctuations with one another). Some of the major wave characteristics like wave Height (H), Time period (T), Wave length (L) significantly influence wave power generation. Interestingly, these ocean waves are dependent on wind ...

1996-09-01

70

Quantitative CT assessment of proximal femoral bone density. An experimental study concerning its correlation to breaking load for femoral neck fractures; Quantitative CT des proximalen Femurs. Experimentelle Untersuchungen zur Korrelation mit der Bruchlast bei Schenkelhalsfrakturen  

Energy Technology Data Exchange (ETDEWEB)

Purpose: In an experimental study, the correlation between the trabecular bone density of the different regions of the proximal femur and the fracture load in the setting of femoral neck fractures was examined. Methods: The bone mineral density 41 random proximal human femora was estimated by single-energy quanitative CT (SE-QCT). The trabecular bone density was measured at the greatest possible extracortical volume at midcapital, midneck and intertrochanteric level and in the 1 cm{sup 3} volumes of the centres of these regions in a standardised 10 mm thick slice in the middle of the femoral neck axis (in mg/ml Ca-hydroxyl apatite). The proximal femora were then isolated and mounted on a compression/bending device under two-legged stand conditions and loaded up to the point when a femoral neck fracture occurred. Results: Statistical analysis revealed a linear correlation between the trabecular bone ...

1997-12-01

71

Association of sea turtles with petroleum platforms in the north-central Gulf of Mexico  

Energy Technology Data Exchange (ETDEWEB)

There are over 4,500 petroleum platforms in the north-central Gulf of Mexico. Explosives are commonly used to remove platforms and have the potential to kill nearby sea turtles. From June 1988-June 1990, the authors used aerial surveys to study turtle density and the spatial relationship between turtles and platforms offshore of Louisiana. They sighted 316 turtles most of which (92%) were loggerheads. Seventy-eight percent were sighted just east of the Mississippi River offshore of the Chandeleur Islands. East of the river, turtle densities ranged from 0.92 (winter) to 4.83 turtles/100 sq km (spring). West of the river, annual densities ranged from 0.11-0.50 turtles/100 sq km. East of the river, three statistical tests indicated that turtles were generally closer to platforms than expected by chance alone. West of the river, turtles were randomly located with respect to platform locations. Before ...

1990-06-01

72

Securing co-operation from persons supplying statistical data  

UK PubMed Central (United Kingdom)

Securing the co-operation of persons supplying information required for medical statistics is essentially a problem in human relations, and an understanding of the motivations, attitudes, and behaviour...Full Text Available

1954-01-01

73

Removal Sampling to Calculate Population Statistics  

Science.gov (United States)

Removal Sampling is an easy-to-use Windows program which calculates population statistics from removal trapping experiment data. Using maximum likelihood methods it ... ...

74

Photon statistics of the free-electron--laser startup  

Energy Technology Data Exchange (ETDEWEB)

We show that, for the high electron currents used in present-day free-electron lasers, spontaneous radiation is distributed according to thermal statistics.

1983-09-01

75

Fermion-boson symmetry through superluminal transformations  

Energy Technology Data Exchange (ETDEWEB)

We consider the Pauli theorem on the spin-statistics connection for faster-than-light particles. As the consequence of the unlocalizability of tachyons in space we conclude that their spin-statistics correlations are inverted.

1985-08-01

76

Advances in Statistical Methods for Substance Abuse Prevention Research  

UK PubMed Central (United Kingdom)

The paper describes advances in statistical methods for prevention research with a particular focus on substance abuse prevention. Standard analysis methods are extended to the typical research...Full Text Available

2003-09-01

77

{open_quotes}Pre-residue{close_quotes} light charged particles from {sup 28}Si+{sup 165}Ho and {sup 16}O+{sup 197}Au, {sup 208}Pb fusion  

Energy Technology Data Exchange (ETDEWEB)

Proton and alpha particle spectral shapes and multiplicities have been measured in coincidence with evaporation residues from {sup 28}Si+{sup 165}Ho and {sup 16}O + {sup 197}Au, {sup 208}Pb fusion reactions. Our experiments used 145 to 220 MeV {sup 28}Si and 115 and 140 MeV {sup 16}O beams produced with the Stony Brook LINAC. ER`s were separated using an electrostatic deflector and detected with large area surface barrier detectors. Light charged particles were detected at forward and backward angles with fourteen single NaI detectors. In the context of the statistical model, charged particle spectra yield information about emission barriers and compound nucleus equilibrium level densities. These are significant ingredients in calculations determining fission timescales from other observables such as pre-scission neutron multiplicities or fusion-evaporation excitation functions. Results will also be compared to analyses of pre-scission charged ...

1993-10-01

78

Wiener Reconstruction of Large-Scale Structure from Peculiar Velocities  

CERN Document Server

We present an alternative, Bayesian method for large-scale reconstruction from observed peculiar velocity data. The method stresses a rigorous treatment of the random errors and it allows extrapolation into poorly sampled regions in real space or in k-space. A likelihood analysis is used to determine the fluctuation power spectrum, followed by a Wiener Filter (WF) analysis to obtain the minimum-variance mean fields of velocity and mass density. Constrained Realizations (CR) are then used to sample the statistical scatter about the WF mean field. The WF/CR method is applied as a demonstration to the Mark III data with 1200 km/s, 900 km/s, and 500 km/s resolutions. The main reconstructed structures are consistent with those extracted by the POTENT method. A comparison with the structures in the distribution of IRAS 1.2Jy galaxies yields a general agreement. The reconstructed velocity field is decomposed into its divergent and tidal components ...

1999-01-01

79

The imaging findings of small({<=}15mm) portal defects in the liver on CT arterial portography : evaluation with CT hepatic arteriography and lipiodol CT  

Energy Technology Data Exchange (ETDEWEB)

To assess the malignant potential of small({<=}15mm) portal defects seen on CT arterial portography, the findings of CT hepatic arteriography and lipiodol CT were reviewed. In 91 patients who underwent both CTAP and CTHA, small portal defects were reviewed for frequency, multiplicity and location. We prospectively evauluated changes in the size and enhancement pattern of malignant lesions on follow up CT according to density on CTHA, location, lipiodol deposits on lipiodol CT, and multiplicity. Among the 91 patients, 102 small defects were defected in 42 patients(46%). Small portal defects were benign, malignant, and of undetermined malignant potential in 77%, 20% and 3% of cases, respectively. Small portal defects that were hyperattenuated on CTHA, and lipiodol deposits on lipiodol CT, were malignant in 42% and 70% of cases, respectively. Location and multiplicity did not show statistically significant variation between benign and ...

1999-05-01

80

The Quantum Vacuum of Complex Media. A Unified Approach to the Dielectric Constant, the Spontaneous Emission and the Zero-Temperature Electromagnetic Pressure  

CERN Document Server

We study from a critical perspective several quantum-electrodynamic phenomena commonly related to vacuum electromagnetic (EM) fluctuations in complex media. We compute the resonance-shift, the spontaneous emission rate, the local density of states and the van-der-Waals-Casimir pressure in a dielectric medium using a microscopic diagrammatic approach. We find, in agreement with some recent works, that these effects cannot be attributed to variations on the energy of the EM vacuum but to variations of the dielectric self-energy. This energy is the result of the interaction of the bare polarizability of the dielectric constituents with the EM fluctuations of an actually polarized vacuum. We have found an exact expression for the spectrum of these fluctuations in a statistically homogeneous dielectric. Those fluctuations turn out to be different to the ones of normal radiative modes. It is the latter that carry the zero-point-energy (ZPE). ...

2009-01-01

81

Statistical studies of Galactic open clusters I. Structural and basic astrophysical parameters  

CERN Document Server

Context. Study of open clusters is important not only for learning properties of these objects but also for understanding the process of formation and evolution of stars and the Milky Way. Aims. The paper contains determination of the global (geometrical and physical) characteristics of a large sample of Galactic open clusters from homogeneous near-infrared photometric data and analysis of mutual relations between those characteristics. Methods. The near-infrared JHK photometric data from the 2-Micron All Sky Survey were used to determine new coordinates of the centres, angular sizes and radial density profiles of 849 open clusters in the MilkyWay. Additionally, for 754 of these clusters age, reddening, distance and linear sizes were also derived. The sample contains 140 open clusters which have not been studied before. Results. The analysed sample contains open clusters with ages in the range from 7 Myr to 10 Gyr. The majority of these clusters are located up to 3 ...

2010-01-01

82

Serviceability of steam generators at NPPs with reactors of the WWER-440 and WWER-1000 types  

Energy Technology Data Exchange (ETDEWEB)

Steam generators (SG) are the weak link of nuclear power plants, their service life is shorter than the service life of other NPP components. This paper is dedicated to a statistical analysis of SG damages and failures. Heat exchanging tubes (HET) are the most damaged elements in SG, there are on average 286 plugged or repaired tubes in each operating SG. The usually mechanisms of tube failure are the following: denting, corrosion at tube outside, pitting, fretting, and circular crack propagation. Most of damages are located in the transition zone above a tube plate. This study shows that the factors that are involved in the SG HET fault probability are: - design features of SG and secondary equipment elements (high pressure feed heaters (HPFH), low pressure feed heater (LPFH)), - water chemistry at different points of condensate feed pipe, composition and density of deposits on HET surface, efficiency of mechanical and chemical washing, - the ...

2002-07-01

83

Residence time probability analysis of sulfur concentrations at Grand Canyon National Park  

Energy Technology Data Exchange (ETDEWEB)

A statistical method is developed to determine the locations of major pollutant sources affecting a distant downwind receptor, provided that air trajectories can be estimated. Probability density functions are estimated which indicate the overall residence time of air parcels over a given geographic region as they travel toward a receptor and residence time for the case of high pollutant concentrations at the receptor. These functions are used to estimate a conditional probability function which indicates the potential for a source region to contribute to high air pollution concentrations. Finally, a source contribution function is formulated to indicate the relative contribution of different source regions to high concentrations at the receptor. The method is tested using data collected at Grand Canyon National Park in 1980. The dominant pathway for air masses arriving at Grand Canyon during this period was southern California. A lesser ...

1985-01-01

84

Ray Tracing Simulations of Weak Lensing by Large-Scale Structure  

CERN Document Server

We investigate weak lensing by large-scale structure using ray tracing through N-body simulations. Photon trajectories are followed through high resolution simulations of structure formation to make simulated maps of shear and convergence on the sky. Tests with varying numerical parameters are used to calibrate the accuracy of computed lensing statistics on angular scales from about 1 arcminute to a few degrees. Various aspects of the weak lensing approximation are also tested. For fields a few degrees on a side the shear power spectrum is almost entirely in the nonlinear regime and agrees well with nonlinear analytical predictions. Sampling fluctuations in power spectrum estimates are investigated by comparing several ray tracing realizations of a given model. For survey areas smaller than a degree on a side the main source of scatter is nonlinear coupling to modes larger than the survey. We develop a method which uses this effect to estimate the mass ...

2000-01-01

85

Optimal Weak Lensing Skewness Measurements  

CERN Document Server

Weak lensing measurements are entering a precision era to statistically map the distribution of matter in the universe. The most common measurement has been of the variance of the projected surface density of matter, which corresponds to the induced correlation in alignments of background galaxies. This measurement of the fluctuations is insensitive to the total mass content, like using waves on the ocean to measure its depths. But when the depth is shallow as happens near a beach, waves become skewed. Similarly, a measurement of skewness in the projected matter distribution directly measures the total matter content of the universe. While skewness has already been convincingly detected, its constraint on cosmology is still weak. We address optimal analyses for the CFHT Legacy Survey in the presence of noise. We show that a compensated Gaussian filter with a width of 2.5 arc minutes optimizes the cosmological constraint, yielding $\\Delta ...

2003-01-01

86

Experimental modelling of a pilot lignocellulosic pellets stove plant  

Energy Technology Data Exchange (ETDEWEB)

Small-scale stoves, producing heat and hot water, are suited for domestic purposes. In order to optimise their efficiency when using lignocellulosic pellets, an important task is to do research on their real performance. The general behaviour depends on many operational factors (air flow and humidity, pressure, etc), dimension and pellet characteristics (moisture, size, raw material, density, friability, etc). In this paper, the first results and general performance of a 24 kW pellet fixed bed stove pilot plant are presented. The plant has been designed to study pellet combustion in the laboratory. The main targets are to reduce emissions of pollutants and to improve energy efficiency. Different situations can be simulated and tested due to its flexible design. Temperatures, pressures, flows and emissions are measured and analysed. An extensive study of different load conditions is presented through the application of both an experiment design technique and the ...

2004-12-01

87

Exemplification of the Game Theory application in auctions of exploratory blocks; Um exemplo de aplicacao de Teoria dos Jogos em leiloes de blocos exploratorios  

Energy Technology Data Exchange (ETDEWEB)

This article describes a methodology to determine the best strategy in an open bid, where oil and gas fields are the targets for exploration. Based upon the previous bid rounds for a given specific area - the Campos Basin, for that matter -, the data were statistically treated to fit a probability density function, modelling the value of bids offered by the competing companies. By means of techniques and concepts pertaining to Game Theory a balance matrix was built for values of bids made by companies as a function of the company alone in assumed bid rounds. At the end of each british auction, participants of this simultaneous game, using the rationality principle, aimed at winning the tender on the oil field aimed for, through the use of better answers with respect to its rival competitor. The game goal was maximize return on investment purchase in the decisions of lease blocks purchases in the auctions, or to try minimize its opponents gains. ...

2003-07-01

88

Direct observation of ordered orbital of YTiO_3 by the X-ray magnetic diffraction technique  

International Nuclear Information System (INIS)

X-ray magnetic diffraction (XMD) technique was applied to an orbital ordering compound of ferromagnetic YTiO_3 for the first time. The orbital-magnetic form factor #mu# _L(k) and the spin-magnetic form factor #mu# _S(k) were independently measured by utilizing the LS separation ability of the XMD. The #mu# _L(k) was measured for ten reciprocal-lattice points. No significant values of the #mu# _L(k) were observed for most of the reciprocal-lattice points within the estimated statistical errors, which suggested quenching of the orbital moment. The #mu# _S(k) was measured for 22 reciprocal-lattice points. Fourier synthesis of the #mu# _S(k) gave the spin density distribution m _S(r) in the real space. The obtained m _S(r) map shows the characteristic feature of the electron distribution of 3d electron in the t_2_g state of a Ti atom coordinated by O"2"- ions, in which the electrons are distributed away from the negative O"2"- ions. It is concluded ...

2005-08-01

89

Correlations between the proton temperature anisotropy and Alfv\\'en-cyclotron waves in the solar wind  

CERN Document Server

Correlations are studied between the power density of Alfv\\'en-cyclotron waves (having frequencies between 0.02 and 2 Hz) and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios-2 primary mission at radial distances from the Sun between 0.3 AU and 0.9 AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion-cyclotron instability. This ...

2010-01-01

90

Comparison Of Reionization Models: Radiative Transfer Simulations And Approximate, Semi-Numeric Models  

CERN Document Server

We compare the predictions of four different algorithms for the distribution of ionized gas during the Epoch of Reionization. These algorithms are all used to run a 100 Mpc/h simulation of reionization with the same initial conditions. Two of the algorithms are state-of-the-art ray-tracing radiative transfer codes that use disparate methods to calculate the ionization history. The other two algorithms are fast but more approximate schemes based on iterative application of a smoothing filter to the underlying source and density fields. We compare these algorithms' resulting ionization and 21 cm fields using several different statistical measures. The two radiative transfer schemes are in excellent agreement with each other (with the cross-correlation coefficient of the ionization fields >0.8 for k 0.6 for k < 1 h/Mpc). When used to predict the 21cm power spectrum at different times during reionization, all ionization algorithms agree with ...

2010-01-01

91

A new lagrangian particle method to describe turbulent flows of fully compressible ideal gases  

CERN Document Server

There are several approaches to describe flows with particles e.g. Lattice-Gas Automata (LGA), Lattice-Boltzmann method (LBM) or smoothed particle hydrodynamics (SPH). These approaches do not use fixed grids on which the Navier-Stokes equations are solved via e.g. finite volume method. The flow is simulated using a multitude of particles or particle density distributions, which interacts and due to statistical laws and an even more fundamental approach than the Navier-Stokes equation, the averaged flow variables can be derived. After a short summary of the most popular particle methods the new DMPC (Dissipative Multiple Particles Collision) approach will be presented. The DMPC-model eliminates some of the weak points of the established particle methods and shows high potential for more accurate CFD solution especially in areas where standard CFD tools still have problems (e.g. aero-acoustics). The DMPC-model deals with discrete circular ...

2008-01-01

92

(n,2n) excitation functions for "5"4Fe, "7"0Ge, "7"4Se, "8"5Rb, sup(86,88)Sr, "8"9Y, "9"2Mo, and "2"0"4Hg in the neutron energy region 13-18 MeV  

International Nuclear Information System (INIS)

Using the activitation method (n,2n) excitation-functions were measured for "5"4Fe, "7"0Ge, "7"4Se, "8"5Rb, sup(86,88)Sr, "8"9Y, "9"2Mo, and "2"0"4Hg in the neutron-energy region 13-18 MeV. The results are checked for consistency by means of a systematic of (n,2n) cross-sections as a function of the nuclear neutron excess (N-Z)/A. Furthermore the data are compared with results from the statistical nuclear reactions theory which were calculated using optical model absorption cross-sections and the Fermi-gas-model formula for the nuclear level density. In the case of "2"0"4Hg the influence of preequilibrium nucleon emission was taken into account. (orig.).

93

The neurotoxic effects of artemether on the cytoarchitecture of the cerebellum of adult male wistar rats  

International Nuclear Information System (INIS)

In a 70kg adult man, artemether is given at a total dosage of 480mg for five days in the treatment of malarial. Using t-test analysis technique at 95% confidence interval i.e t < 0.05 and P - value = 2.26, no significant difference was observed between the average brain and cerebellar weight, the average width of cerebellar cortical layers, the density and the average size of Purkinje Cells in the control groups C1 and C2 and the experimental group E. In the present study, there were no gross or morphological differences between the two groups of animals (control and experimental groups) on day 7 at the completion of experimental procedure. A significant statistical increase in average body weight was observed in the control groups C1 (which received only standard diet and water) and C2 (which received 1.23mg/kg body weight of normal saline intramuscularly in addition to standard diet and water) from 140 + 19.65g on day 1 to 146 + 19.90g on ...

2007-01-01

94

Combining rock physics and sedimentology for seismic reservoir characterization of North Sea turbidite systems  

Science.gov (United States)

The petroleum industry is increasing its focus on the exploration of reservoirs in turbidite systems. However, these sedimentary environments are often characterized by very complex sand distributions. Hence, reservoir description based on conventional seismic and well-log interpretation may be very uncertain. There is a need to employ more quantitative seismic techniques to reveal reservoirs units in these complex systems from seismic amplitude data. In this study we focus on North Sea turbidite systems. Our goal is to improve the ability to use 3D seismic data to map reservoirs in these systems. A cross-disciplinary methodology for seismic reservoir characterization is presented that combines rock physics, sedimentology, and statistical techniques. We apply this methodology to two turbidite systems of Paleocene age located in the South Viking Graben of the North Sea. First, we investigate the relationship between sedimentary petrography and rock physics ...

2000-01-01

95

Osteoporosis and prevention. Assessment of mineral density, geometry and biomechanics of bone by means of peripheral quantitative Computed Tomography (pQCT) in premenopausal women assuming phytoestrogens; Osteoporosi e fitoestrogeni: valutazione della densita' minerale ossea mediante tomografia computerizzata quantitativa periferica nelle donne lattoovovegetariane nella premenopausa  

Energy Technology Data Exchange (ETDEWEB)

Aim of the work was to describe the noninvasive assessment of bone mineral density, geometrical and biochemical properties in premenopausal women with dietary intake of phytoestrogens and comparison of these parameters with those of age-matched female subjects with Mediterranean dietary intake lacking in these substances. Volumetric cortical, trabecular and total mineral density and bone geometrical properties were evaluated with peripheral quantitative computed tomography (pQCT) at the distal radius of the non dominant forearm. pQCT showed higher bone mineral density (total and trabecular) and SSI values in premenopausal with dietary intake of phytoestrogens. Despite the lack of statistical significance, these preliminary results, should further support the few literature findings about the potential role of phytoestrogens consumption in preventing trabecular bone loss. However, further studies are ...

2000-04-01

96

Statistical cut-off criterion  

International Nuclear Information System (INIS)

... radiation effects human populations low dose irradiation neoplasms radiation

1980-01-01

98

Minimization on Stochastic Matroids  

Science.gov (United States)

... Note that the terminal ... Probability and Statistics with Reliability, Queueing, and Computer ... Weiss, G., "Stochastic Bounds on Distributions of Optimal ...

1990-07-01

100

Environmental Economics  

Wastenet

environmental burden is studied by testing the Environmental Kuznets Curve hypothesis as well as application of statistical decomposition

101

Precious Metals in Municipal Solid Waste Incineration Bottom Ash  

Energy Technology Data Exchange (ETDEWEB)

Municipal solid waste incineration (MSWI) bottom ash contains economically significant levels of silver and gold. Bottom ashes from incinerators at Amsterdam and Ludwigshafen were sampled, processed, and analyzed to determine the composition, size, and mass distribution of the precious metals. In order to establish accurate statistics of the gold particles, a sample of heavy non-ferrous metals produced from 15 tons of wet processed Amsterdam ash was analyzed by a new technology called magnetic density separation (MDS). Amsterdam's bottom ash contains approximately 10 ppm of silver and 0.4 ppm of gold, which was found in particulate form in all size fractions below 20 mm. The sample from Ludwigshafen was too small to give accurate values on the gold content, but the silver content was found to be identical to the value measured for the Amsterdam ash. Precious metal value in particles smaller than 2 mm seems to derive mainly from waste ...

2009-04-15

102

Ocean Water: Density  

Science.gov (United States)

This site explains how temperature, pressure, and salinity work together to determine the density of ocean water. The three density layers of the ocean are described by means of text description and a graphic illustration.

103

Density: Sea Water Mixing and Sinking - Aquarius - NASA  

Science.gov (United States)

density is slightly higher, its electrical conductivity is much higher, and it is slightly ... Sea water has characteristic properties (e.g. density) that are independent of ...

104

Statistical treatment of the inner M-shell excitation in heavy ion-atom collisions  

Energy Technology Data Exchange (ETDEWEB)

A statistical treatment has been applied to interpret the experimental data on the Xe M-shell vacancy production in slow 1.05 MeV Xe-Xe collisions and is shown to give better agreement with experiment than that of the molecular-orbital models.

1983-06-27

105

Statistical Support Document for Proposed Effluent Limitations Guidelines and Standards for the Metal Products and Machinery Industry.  

Science.gov (United States)

Table of Contents: Overview of Organization and Contents of Document; Analytical Data Collection Efforts and Definition of Options; Description of Data Conventions; Statistical Methodology: Modified Delta-Lognormal Model; Estimation Under the Modified Del...

2000-01-01

106

SEGMENTING CT PROSTATE IMAGES USING POPULATION AND PATIENT-SPECIFIC STATISTICS FOR RADIOTHERAPY  

UK PubMed Central (United Kingdom)

This paper presents a new deformable model using both population and patient-specific statistics to segment the prostate from CT images. There are two novelties in the proposed method. First,...Full Text Available

2009-08-07

107

OECD Pakistan Aid Statistics  

Science.gov (United States)

Profile of aid statistics to Pakistan. Shows the amount of aid received, the major donors and the form in which the majority of the aid is given. Especially useful when compared to the aid profile of similar countries. Shows that ODA accounts for about 1.5% of Pakistani GDP and that it is distributed over various sectors.

108

NAME=\\  

Wastenet

...Programme Manager Interests Multilevel Statistical Modelling Geography of Health and Health Care Geographical Data Analysis Census Data Analysis Health Services Research (in particular Research Design, Statistical Analysis and Epidemiology) people/mgould.html Homepage | Contacts | Site Map | Privacy Statement | Webmaster | ...

109

A statistical framework for modeling gene expression using chromatin features and application to modENCODE datasets  

UK PubMed Central (United Kingdom)

We develop a statistical framework to study the relationship between chromatin features and gene expression. This can be used to predict gene expression of protein coding genes, as well as microRNAs....Full Text Available

2011-01-01

110

Statistical Indicators Report.  

Science.gov (United States)

... Sick leave usage amounts to 72.4 hours per employee. ... Quits are resignations and individual tran;fers to other Federal Agencies. ...

2011-05-14

111

SAMS Research and Development  

Science.gov (United States)

... resolution video. RESULTS Statistics describing the typical inertial navigation error growth were collected. Typical errors ...

2008-08-06

112

A quantum-statistical-mechanical extension of Gaussian mixture model  

Energy Technology Data Exchange (ETDEWEB)

We propose an extension of Gaussian mixture models in the statistical-mechanical point of view. The conventional Gaussian mixture models are formulated to divide all points in given data to some kinds of classes. We introduce some quantum states constructed by superposing conventional classes in linear combinations. Our extension can provide a new algorithm in classifications of data by means of linear response formulas in the statistical mechanics.

2008-01-15

116

Image Descriptors for Displays  

Science.gov (United States)

... 44 2. Luminance Power Spectral Density Measurements ..... 44 ... 50 4. Chrominance Power Spectral Density Measurements ..... 53 ...

1977-02-01

117

Reduced resolution polarimetric imagery characterization of the 1990 Galveston Bay oil spill  

Energy Technology Data Exchange (ETDEWEB)

Low resolution visual polarimetric photographic imagery of the Galveston Bay oil spill from a tanker accident on July 28, 1990 was obtained and analyzed. The low resolution imagery (30 to 100 meters) was obtained concurrently with high resolution (1 meter), and is representative of what would be seen by a polarimetric satellite. Orthogonal red-green-blue (RGB) polarimetric images obtained with color photography were digitized by KODALUX on to a CD ROM. These polarimetric images were then used to calculate the percent polarization. The positive and negative percent polarized radiation scattered by each of the sea surface waves is seen individually in high resolution imagery. (Percent polarization is defined as positive when the dominant radiation is perpendicular to the plane of incidence and negative when it is parallel). The analysis of low resolution polarimetry is approached in a different manner than high resolution; in high resolution, individual waves are imaged and the ...

1997-06-01

118

Quantitative descriptions of nonlinear gravitational galaxy clustering  

Energy Technology Data Exchange (ETDEWEB)

In order to investigate nonlinear gravitational galaxy clustering, three different quantitative analyses were carried out: two-point correlation functions, {xi}(r); fractal dimensions, D{sub q}; and f(N) statistics. The relation between the exponent {gamma} of the correlation function ({xi}(r) {proportional to} r{sup -{gamma}}) and the fractal dimensions, D{sub q}, was derived with the help of the probability distribution function, f(N), for finding N galaxies within a volume V. The methods were applied to analyze the results of N-body simulations with power law initial density fluctuations ( {delta}{sub k} {sup 2} {proportional to} k{sup n}, n = 1, 0, -1 and -2). These analyses show that the exponent, {gamma}, of the power law {xi}(r) is approximately 2 in the nonlinear regime for models with n = 1 and 0. For models with n = -1 and -2, the correlation functions comprise two parts of the intermediate and small scales in the nonlinear regime. ...

1990-01-01

119

Isobutane/2-butene alkylation over potential heterogeneous catalysts in a slurry reactor  

Energy Technology Data Exchange (ETDEWEB)

The trend towards more effective use of fossil fuels and reduced environmental pollution represents a major task of improvement within the refinery processes. The highly isomerized and high octane paraffins produced from isobutane and light olefins by alkylation fulfill all the requirements for reformulated gasoline. This doctoral thesis discusses new catalyst systems because of their potential in alkylation. A slurry reactor apparatus for solid-acid catalysed isobutane/butene alkylation was developed and used to investigate the performance of various heterogeneous catalysts. The selected materials were mainly zeolite types with faujasite structures. The samples were characterized by various methods before alkylation. In general, the order of decreasing catalyst activity after 3 h of reaction at 80{sup o}C was found to be: H-EMT >> H-FAU, dealuminated H-FAU >> NS.500, TA-Y, CeY-98 > Nafion-H. The order of decreasing alkylate selectivity of the catalysts was: H-EMT ...

1996-12-31

120

Investigation of the effect of laundering the ground crew chemical defense overgarment on toxic-free-area vapor transfer during shelter entry by initially contaminated personnel. Interim report, Oct 87-Jan 88  

Energy Technology Data Exchange (ETDEWEB)

A study by the U.S. Air Force School of Aerospace Medicine, Brooks AFB, Texas, has compared the shelter processing transfer of chemical warfare agent simulant vapor for subjects wearing unwashed and laundered ground-crew chemical defense overgarments. Twice laundered and four times laundered protective garments were included in the assessment. Test subjects, wearing the unwashed and laundered protective garments were initially sprayed with liquid simulant (methyl salicylate) to a target density of 5 g m-2. They were then sequentially processed into and through the USAFSAM Collective Protection Shelter (SCPS-2B) test facility. Immediately upon entry to the Toxic-Free Area, the subjects were confined in individual off gassing booths for 2 h while offgassed simulant vapor concentration in the booths was recorded. The resulting mean maximum vapor concentrations recorded in the booths for subjects who had worn unwashed and laundered overgarments prior to booth entry ...

1990-12-01

121

Direct observation of ordered orbital of YTiO{sub 3} by the X-ray magnetic diffraction technique  

Energy Technology Data Exchange (ETDEWEB)

X-ray magnetic diffraction (XMD) technique was applied to an orbital ordering compound of ferromagnetic YTiO{sub 3} for the first time. The orbital-magnetic form factor {mu} {sub L}(k) and the spin-magnetic form factor {mu} {sub S}(k) were independently measured by utilizing the LS separation ability of the XMD. The {mu} {sub L}(k) was measured for ten reciprocal-lattice points. No significant values of the {mu} {sub L}(k) were observed for most of the reciprocal-lattice points within the estimated statistical errors, which suggested quenching of the orbital moment. The {mu} {sub S}(k) was measured for 22 reciprocal-lattice points. Fourier synthesis of the {mu} {sub S}(k) gave the spin density distribution m {sub S}(r) in the real space. The obtained m {sub S}(r) map shows the characteristic feature of the electron distribution of 3d electron in the t{sub 2g} state of a Ti atom coordinated by O{sup 2-} ions, in which the electrons are ...

2005-08-15

122

Correlation of angiogenesis with "1"8F-FMT and "1"8F-FDG uptake in non-small cell lung cancer  

International Nuclear Information System (INIS)

L-[3-"1"8F]-#alpha#-methyltyrosine ("1"8F-FMT) is an amino-acid tracer for positron-emission tomography (PET). We have conducted a clinicopathologic study to elucidate the correlation of angiogenesis with "1"8F-FMT and 2-["1"8F]-fluoro-2-deoxy-D-glucose ("1"8F-FDG) uptake in patients with non-small cell lung cancer (NSCLC). Thirty-seven NSCLC patients were enrolled in this study, and two PET studies with "1"8F-FMT and "1"8F-FDG were performed. Uptake of PET tracers was evaluated with standardized uptake value. Vascular endothelial growth factor (VEGF), CD31, CD34, L-type amino acid transporter 1 (LAT1) and Ki-67 labeling index of the resected tumors were analyzed by immunohistochemical staining, and correlated with the clinicopathologic variables and the uptake of PET tracers. The median VEGF rate was 45% (range, 10-78%). High expression was seen in 30 patients (81%, 30/37). VEGF expression was statistically associated with progressively growing microvessel count. ...

2009-04-01

123

A Liquid Parahydrogen Target for the Measurement of a Parity-violating Gamma Asymmetry in Polarized Neutron Capture on Protons  

Energy Technology Data Exchange (ETDEWEB)

A 16 l liquid parahydrogen target has been developed for a measurement of the parity-violating {gamma}-asymmetry in the capture of polarized cold neutrons on protons in the {rvec n} + p {yields} d + {gamma} reaction by the NPDGamma collaboration. The target system was carefully designed to meet the stringent requirements on systematic effects for the experiment and also to satisfy hydrogen safety requirements. The target was designed to preserve the neutron polarization during neutron scattering on liquid hydrogen (LH{sub 2}), optimize the statistical sensitivity to the {rvec n} + p {yields} d + {gamma} reaction, minimize backgrounds coming from neutron interaction with the beam windows of the target cryostat, minimize LH{sub 2} density fluctuations which can introduce extra noise in the gamma asymmetry signal, and control systematic effects. The target incorporates two mechanical refrigerators, two ortho-para convertors, an aluminum cryostat, ...

2010-05-01

124

WASTE SOLIDIFICATION BUILDING BENCH SCALE HIGH ACTIVITY WASTE SIMULANT VARIABILITY STUDY FY2008  

Energy Technology Data Exchange (ETDEWEB)

The primary objective of this task was to perform a variability study of the high activity waste (HAW) acidic feed to determine the impact of feed variability on the quality of the final grout and on the mixability of the salt solution into the dry powders. The HAW acidic feeds were processed through the neutralization/pH process, targeting a final pH of 12. These fluids were then blended with the dry materials to make the final waste forms. A secondary objective was to determine if elemental substitution for cost prohibitive or toxic elements in the simulant affects the mixing response, thus providing a more economical simulant for use in full scale tests. Though not an objective, the HAW simulant used in the full scale tests was also tested and compared to the results from this task. A statistically designed test matrix was developed based on the maximum molarity inputs used to make the acidic solutions. The maximum molarity inputs were: 7.39 HNO{sub 3}, 0.11618 ...

2009-03-20

125

Density Currents  

Science.gov (United States)

In this activity, students will make a turbidity current. They will discover how fluids of differing densities interact with one another, learn some ways the densities of fluids can be changed and observe how density currents transport and deposit tremendous amounts of sediment in lakes and in the ocean. Additional options allow students to create and observe different kinds of density currents.

126

unido.org  

Wastenet

...Events Archive Worldwide Africa Programme Arab Programme Asia and Pacific Programme Europe and NIS Programme Latin American and Caribbean Programme Least-Developed Countries South-South Cooperation Human Security Directory of Offices Research & Statistics Publications Research and Statistics Subsites Annual Report Evaluation Group Investment and Technology Promotion Policymaking Organs Legal Resources Goodwill Ambassadors Industrial Competitiveness and Trade Private Sector Development Environmental Management Energy and Climate Change Research and Statistics Financial Institutions Partnerships Thematic ...Events Archive Worldwide Africa Programme Arab Programme Asia and Pacific Programme Europe and NIS Programme Latin American and Caribbean Programme Least-Developed Countries South-South Cooperation Human Security Directory of Offices Research & Statistics Publications Research and ...

127

Theory of the crystal-liquid phase transition  

Science.gov (United States)

The SCF approximation is used in a statistical theory of melting based on equality of the chemical potentials. The results for the melting points of the inert gases are close to the observed values.

1967-02-01

128

The Natural Statistics of Audiovisual Speech  

UK PubMed Central (United Kingdom)

Humans, like other animals, are exposed to a continuous stream of signals, which are dynamic, multimodal, extended, and time varying in nature. This complex input space must be transduced and sampled...Full Text Available

2009-07-01

129

Streams of solid municipal wastes. Evaluation of data on the basis of waste follow-up system; Kiinteaen yhdyskuntajaetteen virrat: aineistotarkastelua jaetealan seurantajaerjestelmaen avulla  

Energy Technology Data Exchange (ETDEWEB)

The follow-up system for wastes (JAeSTI), developed at the end of the 1990s, forms a basis for today's followup activities in Finland. JAeSTI relies on an environmental protection database, the compliance monitoring system VAHTI operated by the environmental authorities. Waste followup and waste statistics depend very much on the annual waste quantities recorded in the VAHTI system. In the KYJ-project the coverage and reliability of the data in the VAHTI system was evaluated as for the streams of solid municipal waste. The project also included the compiling of national statistics on municipal waste for the year 2000. The project used other information sources, too, such as statistics compiled when the National Waste Plan and regional waste plans were revised in 2002. In addition, the extent and quantity of in-situ (household) composting and incineration were assessed on the basis of a separate study (Annex 2, In ...

2004-07-01

130

Statistical methods for environmental pollution monitoring  

Energy Technology Data Exchange (ETDEWEB)

This volume covers planning, design, and data analysis. It offers statistical methods for designing environmental sampling and monitoring programs as well as analyzing the resulting data. Statistical sample survey methods to problems of estimating average and total amounts of environmental pollution are presented in detail. The book also provides a broad array of statistical analysis methods for many purposes...numerous examples...three case studies...end-of-chapter questions...computer codes (showing what output looks like along with its interpretation)...a discussion of Kriging methods for estimating pollution concentration contours over space and/or time...nomographs for determining the number of samples required to detect hot spots with specified confidence...and a description and tables for conducting Rosner's test to identify outlaying (usually large) pollution measurements in a data set.

1986-01-01

131

Statistical estimation of the lifetimes of charmed particles  

Energy Technology Data Exchange (ETDEWEB)

Various statistical methods for the estimation of the mean lifetimes of charmed particles have been considered. It is shown that the usual estimates of the maximum likelihood in some cases do not exist or may have rather great positive bias, if the statistics are low. Alternative estimates of the mean lifetime tau are discussed. Among them the 'jackknife' estimate of tau is considered. The minimum variance unbiased estimates of the average rate of decay 1/tau have been derived for some particular cases. It is also shown that the usual estimate of the ratio of the mean lifetimes of different kinds of particles may also have a bias when the statistics are poor. Two methods of reducing this bias have been proposed.

1984-12-15

132

Sample manuscript showing specifications and style - NASA ...  

Science.gov (United States)

Figure 7: Horak Cost Estimating Relationship with Statistical Details. For this comparison, we ignore the Material (glass vs metal) and Design (on vs ...

133

Reduction of statistic error in Mihalczo subcriticality measurement  

Energy Technology Data Exchange (ETDEWEB)

The theoretical formula for the statistical error estimation in Mihalczo method was derived, and the dependence of the error were investigated on the facility to be measured and on the parameter in the data analysis. The formula was derived based on the reactor noise theory and the error theory for the frequency analysis, and found that the error depends on such parameters as the prompt neutron decay constant, detector efficiencies, and the frequency bandwidth. Statistical errors estimated with the formula was compared with experimental values and verified to be reasonable. Through parameter surveys, it is found that there is an optimum combination of the parameters to reduce the magnitude of the errors. In the experiment performed in DCA subcriticality measurement facility, it is estimated experimentally that the measurement requires 20 minutes to obtain the statistic error of 1% for the keff 0.9. According to the error ...

1998-08-01

134

Quantum field theory of particles with braid group statistics in 2+1 dimensions  

CERN Document Server

The present thesis is concerned with the local quantum physics of relativistic particles and fields in three space-time dimensions, whose statistics is to be described by a representation of the braid group -- so-called plektons or, if the representation is Abelian, anyons. In particular the issue of the existence of free anyonic fields is addressed. In our context, these are operators affiliated with the 'local' field algebras and creating only single particle vectors from the vacuum. (Localizability here refers to regions extending to infinity in some spacelike direction.) Under a mild regularity condition for these fields, we can derive commutation relations which are not compatible with braid group statistics. Further, model-independent results concerning the PCT operator and the connection of spin and statistics are obtained. Assuming the observable algebra to satisfy the Bisognano-Wichmann theorem, a PCT theorem for ...

1997-01-01

135

Physics of chemoreception.  

UK PubMed Central (United Kingdom)

Statistical fluctuations limit the precision with which a microorganism can, in a given time T, determine the concentration of a chemoattractant in the surrounding medium. The best a cell can do is...Full Text Available

1977-11-01

136

On the statistical estimation of the lifetimes of charmed particles  

Energy Technology Data Exchange (ETDEWEB)

Various statistical methods for the estimation of the mean lifetimes of charmed particles have been considered. It is shown that the usual estimates of the maximum likelihood in some cases do not exist or may have rather great positive bias, if the statistics are low. Alternative estimates of the mean lifetime tau are discussed. Among them the 'jackknife' estimate of tau is considered. The minimum variance unbiased estimates of the average rate of decay 1/tau have been derived for some particular cases. It is also shown that the usual estimate of the ratio of the mean lifetimes of different kinds of particles may alos have a bias when the statistics are poor. Two methods of reducing this bias have been proposed. (orig.).

1984-12-15

137

Nuclear power plant personnel training in France  

International Nuclear Information System (INIS)

Data on French nuclear electricity generation sites, nuclear power plant operations personnel, operation simulators, nuclear training centers and training statistics are presented.

1994-03-21

138

NURE aerial gamma-ray and magnetic reconnaissance survey: southeastern area-Alaska, Port Alexander Quadrangle  

International Nuclear Information System (INIS)

The flight line profile data and statistical analysis results for the Port Alexander Quadrangle in southeast Alaska are presented.

139

Energy statistics manual  

Energy Technology Data Exchange (ETDEWEB)

Detailed, complete, timely and reliable statistics are essential to monitor the energy situation at a country level as well as at an international level. Energy statistics on supply, trade, stocks, transformation and demand are indeed the basis for any sound energy policy decision. For instance, the market of oil -- which is the largest traded commodity worldwide -- needs to be closely monitored in order for all market players to know at any time what is produced, traded, stocked and consumed and by whom. In view of the role and importance of energy in world development, one would expect that basic energy information to be readily available and reliable. This is not always the case and one can even observe a decline in the quality, coverage and timeliness of energy statistics over the last few years.

2010-07-01

140

Development Statistics for the UH-1 Ada Feasibility Study  

Science.gov (United States)

... to the actual size base on the terminal semicolon counting ... I Queue and stack control. ... analysis: highly accurate analysis of noisy, stochastic data. ...

1992-01-01

141

Comparing healthcare outcomes.  

UK PubMed Central (United Kingdom)

Governments are increasingly concerned to compare the quality and effectiveness of healthcare interventions but find this a complex matter. Crude hospital statistics can be dangerously misleading and...Full Text Available

1994-06-04

142

CHANEXTDFS - Chandra Extended Deep Field South Survey Point Source ...  

Science.gov (United States)

Jan 25, 2006 ... Source positions are determined using matched-filter and centroiding .... The upper 1-sigma statistical error in the full-band counts. ...

143

CDC Data & Statistics | Feature: Drowning Risks in Natural Water...  

Science.gov (United States)

swimmers in or around the water. Designate a responsible adult who can swim and knows CPR to watch swimmers in or around water. The supervisor should not be involved in any...

2011-09-24

144

CBSD Version 2 Component Models of the IR Celestial ...  

Science.gov (United States)

... 1-sigma ZOHF pixel-to-plxel statistical fluctuations ... Spatial frequency filtering shows distinct bands, but miss ... LOS emissivity at the point of closest ...

1990-12-07

145

A proposition of 3D inertial tolerancing to consider the statistical combination of the location and orientation deviations  

CERN Document Server

Tolerancing of assembly mechanisms is a major interest in the product life cycle. One can distinguish several models with growing complexity, from 1-dimensional (1D) to 3-dimensional (3D) (including form deviations), and two main tolerancing assumptions, the worst case and the statistical hypothesis. This paper presents an approach to 3D statistical tolerancing using a new acceptance criterion. Our approach is based on the 1D inertial acceptance criterion that is extended to 3D and form acceptance. The modal characterisation is used to describe the form deviation of a geometry as the combination of elementary deviations (location, orientation and form). The proposed 3D statistical tolerancing is applied on a simple mechanism with lever arm. It is also compared to the traditional worst-case tolerancing using a tolerance zone.

2010-01-01

146

Influence of obesity on the metabolism of apolipoprotein B in humans.  

UK PubMed Central (United Kingdom)

The influence of obesity on the metabolism of apolipoprotein B (apo B) in very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) was investigated...Full Text Available

1985-08-01

147

Diverse Range of Small Peptides Associated With High-Density Lipoprotein  

UK PubMed Central (United Kingdom)

High-density lipoproteins (HDL) were examined as potential carriers of small peptides in plasma. HDL purified by density gradient centrifugation was delipidated and fractionated by size-exclusion...Full Text Available

2006-02-17

148

Coping with crowds: Density-dependent disease resistance in desert locusts  

UK PubMed Central (United Kingdom)

Parasite transmission generally exhibits some form of positive density dependence. Thus, as population density increases, so too does the per capita risk of becoming infected. Under...Full Text Available

2002-04-16

149

A comparison of plotless density estimators using Monte Carlo simulation on totally enumerated field data sets  

UK PubMed Central (United Kingdom)

BackgroundPlotless density estimators are those that are based on distance measures rather than counts per unit area (quadrats or plots) to estimate the density of some usually stationary...Full Text Available

150

THE EVOLUTION OF THE STAR FORMATION RATE OF GALAXIES AT 0.0 #<=# z #<=# 1.2  

International Nuclear Information System (INIS)

We present the 24 #mu#m rest-frame luminosity function (LF) of star-forming galaxies in the redshift range 0.0 #<=# z #<=# 0.6 constructed from 4047 spectroscopic redshifts from the AGN and Galaxy Evolution Survey of 24 #mu#m selected sources in the Booetes field of the NOAO Deep Wide-Field Survey. This sample provides the best available combination of large area (9 deg"2), depth, and statistically complete spectroscopic observations, allowing us to probe the evolution of the 24 #mu#m LF of galaxies at low and intermediate redshifts while minimizing the effects of cosmic variance. In order to use the observed 24 #mu#m luminosity as a tracer for star formation, active galactic nuclei (AGNs) that could contribute significantly at 24 #mu#m are identified and excluded from our star-forming galaxy sample based on their mid-IR spectral energy distributions or the detection of X-ray emission. Optical emission line diagnostics are considered for AGN identification, ...

2010-08-01

151

Response surface characterization of impact damage and residual strength degradation in composite sandwich panels  

Science.gov (United States)

The influence of material configuration and impact parameters on the damage tolerance characteristics of sandwich composites comprised of carbon-epoxy woven fabric facesheets and Nomex honeycomb cores was investigated using empirically based response surfaces. A series of carefully selected tests were used to isolate the coupled influence of various combinations of the number of facesheet plies, core density, core thickness, impact energy, impactor diameter, and impact velocity on the damage formation and residual strength degradation due to normal impact. The ranges of selected material parameters were typical of those found in common aircraft applications. The diameter of the planar damage area associated with Through Transmission Ultrasonic C-scan measurements and the peak residual facesheet indentation depth were used to describe the extent of internal and detectable surface damage, respectively. Standard analysis of variance techniques were used to assess the ...

2003-01-01

152

Plasma production and flow in negative ion beams  

Science.gov (United States)

Plasma generated in low-density vapor by a negative ion beam has been studied experimentally and computationally. We show that space charge neutralization of the beam occurs at very low vapor density, and that correspondingly the electron density may be much less than the beam and plasma ion densities. When there is a large local gas density, as in a charge changing cell, the resulting high electron density is also localized to the same region. Therefore, very few electrons will reach a negative ion accelerator even if it is placed one or two beam diameters from such a cell.

1977-09-21

153

Synthesizer Stability Evaluation - NASA Technical Report Server (NTRS)  

Science.gov (United States)

verified via high-resolution spectral density measurements using the Hadamard Variance. .... spectral density measurements were made with the HF5390 ...

154

Power spectral density measurements with "2"5"2Cf for a mockup of the FFTF  

International Nuclear Information System (INIS)

... californium 252 fftf reactor mockup power density reactor cores reactor noise

1975-06-08

155

Modelling of density limit phenomena in toroidal helical plasmas  

Energy Technology Data Exchange (ETDEWEB)

The physics of density limit phenomena in toroidal helical plasmas based on an analytic point model of toroidal plasmas is discussed. The combined mechanism of the transport and radiation loss of energy is analyzed, and the achievable density is derived. A scaling law of the density limit is discussed. The dependence of the critical density on the heating power, magnetic field, plasma size and safety factor in the case of L-mode energy confinement is explained. The dynamic evolution of the plasma energy and radiation loss is discussed. Assuming a simple model of density evolution, of a sudden loss of density if the temperature becomes lower than critical value, then a limit cycle oscillation is shown to occur. A condition that divides the limit cycle oscillation and the complete radiation collapse is discussed. This model seems to explain the ...

2000-03-01

156

Local Electrostatic Moments and Periodic Boundary Conditition  

Energy Technology Data Exchange (ETDEWEB)

Electronic structure calculations frequently invoke periodic boundary conditions to solve for electrostatic potentials. For systems that are electronically charged, or contain dipole (or higher) moments, this artifice introduces spurious potentials due to the interactions between the system and multipole moments of its periodic images in aperiodic directions. I describe a method to properly handle the multipole moments of the electron density in electronic structure calculations using periodic boundary conditions. The density for which an electrostatic potential is to be evaluated is divided into two pieces. A local density is constructed that matches the desired moments of the full density, and its potential computed treating this density as isolated. With the density of this local moment countercharge removed from the full density, the ...

1998-12-04

157

Investigation of Behaviorally Modified Rats for Use in ...  

Science.gov (United States)

... F;qure Title phge 20 Rat B Spectral Density Measurements TNT Stimuli 70 21 Rat B Spectral Density Measurements Neutral Stimuli 71 ...

1981-12-01

158

Filtered Density Function for Subgrid Scale Modeling of ...  

Science.gov (United States)

... Compilation Part Notice ADP023645 TITLE: Filtered Density Function for Subgrid Scale Modeling of Turbulent Diffusion Flames ...

2006-06-01

159

DSN Radio Science ... - InterPlanetary Network (IPN) Progress Report  

Science.gov (United States)

tions, final noise-power spectral density measurements were made. These measurements of the noise-power spectral density were not the desired phase- noise ...

160

DESIGN, IMPLEMENTATION AND TESTING OF ... - LAMBDA - NASA  

Science.gov (United States)

FIG. 4. Power Spectral Density of the MAP W11 radiometer. The red and black traces are the power spectral density measurements of the two detectors on the ...

161

Atomic density functions: atomic physics calculations analyzed with methods from quantum chemistry  

CERN Document Server

This contribution reviews a selection of findings on atomic density functions and discusses ways for reading chemical information from them. First an expression for the density function for atoms in the multi-configuration Hartree--Fock scheme is established. The spherical harmonic content of the density function and ways to restore the spherical symmetry in a general open-shell case are treated. The evaluation of the density function is illustrated in a few examples. In the second part of the paper, atomic density functions are analyzed using quantum similarity measures. The comparison of atomic density functions is shown to be useful to obtain physical and chemical information. Finally, concepts from information theory are introduced and adopted for the comparison of density functions. In particular, based on the Kullback--Leibler form, a ...

2011-01-01

162

Tube problems: worldwide statistics reviewed  

International Nuclear Information System (INIS)

EPRI's Steam Generator Strategic Management Project issues an annual report on the progress being made in tackling steam generator problems worldwide, containing a wealth of detailed statistics on the status of operating units and degradation mechanisms encountered. A few highlights are presented from the latest report, issued in October 1993, which covers the period to 31 December 1992. (Author).

163

The world energy consumption in 2001. Statistical yearbook ENERDATA 2002  

Energy Technology Data Exchange (ETDEWEB)

Statistical data on the world energy consumption are given to illustrate the following situation in 2001: the deceleration of the world economic growth and the high prices of oil slowed down the progression of the energy consumption: 0,7 % in 2001; stagnation of the gas and oil consumption and strong progression for coal and electricity in 2001; the deceleration for gas marks a strong inflection compared to the past trends. (A.L.B.)

2002-07-01

164

Technical Documentation and Verification for the Buildings Module in the Visual Sample Plan (VSP) Software  

Science.gov (United States)

Visual Sample Plan (VSP) is an easy-to-use visual and graphic statistically-based software tool being developed by the Pacific Northwest National Laboratory (PNNL) to help determine the appropriate number and location of environmental samples so that environmental decisions can be made with the required confidence. The VSP software, which is available free at http://dqo.pnl.gov/vsp, is a significant aid in developing probability-based sampling designs (number and location of samples and measurements) using the Data Quality Objectives (DQO) planning process developed by the U.S. Environmental Protection Agency (EPA). VSP also has the capability of conducted statistical analyses to provide descriptive statistical summaries of data sets, to test whether data are normally distributed, and to compute upper confidence limits on means. This report is the latest in a series of reports that document the ...

2005-06-30

165

Statistical support document for proposed effluent limitations guidelines and standards for the pulp, paper, and paperboard. Point source category  

Energy Technology Data Exchange (ETDEWEB)

The document describes the statistical analyses of data on pollutant loadings in effluent wastestreams from pulp, paper, and paperboard facilities. Included are the analyses that support the revised subcategorization and proposed effluent limitations for biochemical oxygen demand and total suspended solids based upon the best practicable control technology currently available.

1993-11-01

166

Statistical study of pulsar rotational braking  

International Nuclear Information System (INIS)

Pacini (1973) has considered basic theoretical expectations regarding the magnetic dipole radiation and unipolar induction of pulsars, taking into account observational results. The present investigation is concerned with the difference between the two braking mechanisms. Attention is also given to a statistical study involving a comparison of the two braking mechanisms with observations. The study makes use of the observational data for the distribution of apparent beamwidth, and a geometrical method. The obtained results agree with the theory of magnetic dipole radiation.

167

Statistical mapping analysis of serotonin synthesis images generated in healthy volunteers using positron-emission tomography and alpha-[11C]methyl-L-tryptophan.  

UK PubMed Central (United Kingdom)

OBJECTIVES: To assess the suitability of analyzing functional images of brain serotonin (5-HT) synthesis with statistical parametric mapping (SPM), and to investigate further possible sex-related regional...Full Text Available

2000-09-01

168

Software for Data Analysis Programming with R  

CERN Document Server

Although statistical design is one of the oldest branches of statistics, its importance is ever increasing, especially in the face of the data flood that often faces statisticians. It is important to recognize the appropriate design, and to understand how to effectively implement it, being aware that the default settings from a computer package can easily provide an incorrect analysis. The goal of this book is to describe the principles that drive good design, paying attention to both the theoretical background and the problems arising from real experimental situations. Designs are motivated t

2008-01-01

169

Monthly energy review, October 1998  

Energy Technology Data Exchange (ETDEWEB)

The Monthly Energy Review (MER) presents an overview of the Energy Information Administration`s recent monthly energy statistics. The statistics cover the major activities of US production, consumption, trade, stocks, and prices for petroleum, natural gas, coal, electricity, and nuclear energy. Also included are international energy and thermal and metric conversion factors. 37 figs., 61 tabs.

1998-10-01

170

Monthly Energy Review  

Energy Technology Data Exchange (ETDEWEB)

This publication presents an overview of the Energy information Administration`s recent monthly energy statistics. The statistics cover the major activities of US production, consumption, trade, stocks, and prices for petroleum, natural gas, coal, electricity, and nuclear energy. Also included are international energy and thermal and metric conversion factors. Two brief ``energy plugs`` (reviews of EIA publications) are included, as well.

1996-05-28

171

Generalized supersymmetry on Riemann surfaces and the associated string models  

Energy Technology Data Exchange (ETDEWEB)

The authors propose a generalization of the concept of supersymmetry non Riemann surfaces. Generators of this symmetry intermix M fields of different spin. Two types of statistics, i.e., bosonic and fermionic statistics, are allowed for parameters of infinitesimal transformations. They also study the possibility of string models associated with these symmetries. The algebraic structure of a part of generalized supersymmetry is regarded as a sort of an M-th root of the Virasoro algebra.

1988-11-01

172

Electricity supply in the United Kingdom. Brief details and statistics  

Energy Technology Data Exchange (ETDEWEB)

Statistical detail is given of the electricity generation and transmission systems in the UK. Breakdown by type of station, by fuel and the proportion generated by others apart from the generating or area boards is presented. Figures are provided for the various high voltage transmission lines in terms of route and circuit length as well as the number of towers and the capacity of mains transformers.

1987-06-01

173

Electric loading of power transmission lines - statistical methodology and real time management; Carregamento eletrico de linhas de transmissao - metodologia estatistica e gerenciamento em tempo real  

Energy Technology Data Exchange (ETDEWEB)

This paper shows a computerized system, that adopt a statistical methodology and simultaneous measurements of wind velocity and environment temperature, as an experiences at the power transmission lines with environmental monitoring systems. 9 figs., 16 refs.

1991-12-31

174

ADAPTATION OF THE ADVANCED STATISTICAL TRAJECTORY REGIONAL AIR POLLUTION (ASTRAP) MODEL TO THE EPA VAX COMPUTER - MODIFICATIONS AND TESTING  

Science.gov (United States)

The Advanced Statistical Trajectory Regional Air Pollution (ASTRAP) model simulates long-term transport and deposition of oxides of and nitrogen. t is a potential screening tool for assessing long-term effects on regional visibility from sulfur emission sources. owever, a rigorou...

175

A statistical study of pulsar rotational braking  

International Nuclear Information System (INIS)

A previous study described the basic theoretical expectations of the magnetic dipole radiation and unipolar induction of pulsars and presented observational results. This paper further discusses the difference between the two braking mechanisms and analyses the results of a statistical study through observed data of apparent beamwidth's distributions and a geometrical method. The theory of magnetic dipole radiation of pulsars agrees with the observations. Unipolar induction as a braking mechanism is not consistent with the observations.

176

A statistical pattern recognition paradigm for structural health monitoring  

Energy Technology Data Exchange (ETDEWEB)

The process of implementing a damage detection strategy for aerospace, civil and mechanical engineering infrastructure is referred to as structural health monitoring (SHM). Here damage is defined as changes to the material and/or geometric properties of these systems, including changes to the boundary conditions and system connectivity, which adversely affect the system's current or future performance. Our approach is to address the SHM problem in the context of a statistical pattern recognition paradigm (Farrar, Nix and Doebling, 2001). In this paradigm, the process can be broken down into four parts: (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Model Development for Feature Discrimination. When one attempts to apply this paradigm to data from 'real-world' structures, it quickly becomes apparent that data cleansing, normalization, fusion and compression, which can be ...

2004-01-01

177

Privately Releasing Conjunctions and the Statistical Query Barrier  

CERN Document Server

Suppose we would like to know all answers to a set of statistical queries C on a data set up to small error, but we can only access the data itself using statistical queries. A trivial solution is to exhaustively ask all queries in C. Can we do any better? + We show that the number of statistical queries necessary and sufficient for this task is---up to polynomial factors---equal to the agnostic learning complexity of C in Kearns' statistical query (SQ) model. This gives a complete answer to the question when running time is not a concern. + We then show that the problem can be solved efficiently (allowing arbitrary error on a small fraction of queries) whenever the answers to C can be described by a submodular function. This includes many natural concept classes, such as graph cuts and Boolean disjunctions and conjunctions. In doing so we also give a new learning algorithm for submodular functions that ...

2010-01-01

178

Bidirectional reaction steps in metabolic networks: II. Flux estimation and statistical analysis.  

Science.gov (United States)

Metabolic carbon labelling experiments enable a large amount of extracellular fluxes and intracellular carbon isotope enrichments to be measured. Since the relation between the measured quantities and the unknown intracellular metabolic fluxes is given by bilinear balance equations, flux determination from this data set requires the numerical solution of a nonlinear inverse problem. To this end, a general algorithm for flux estimation from metabolic carbon labelling experiments based on the least squares approach is developed in this contribution and complemented by appropriate tools for statistical analysis. The linearization technique usually applied for the computation of nonlinear confidence regions is shown to be inappropriate in the case of large exchange fluxes. For this reason a sophisticated compactification transformation technique for nonlinear statistical analysis is developed. Statistical analysis is then ...

1997-07-01

179

THE INFLUENCE OF GRAIN BOUNDARY CARBIDE ...  

Science.gov (United States)

... Title : THE INFLUENCE OF GRAIN BOUNDARY CARBIDE DENSITY ON THE BRITTLE FRACTURE OF FERRITE PEARLITE STEELS. ...

181

Development and Fabrication of Compositions for 155-mm ...  

Science.gov (United States)

... Descriptors : *PROPELLING CHARGES, *NITROCELLULOSE, *COMBUSTIBLE CARTRIDGE CASES, DENSITY, FIBERS, MANUFACTURING ...

1982-10-01

182

Density changes in amorphous Pd{sub 80}Si{sub 20} during low temperature ion irradiation  

Energy Technology Data Exchange (ETDEWEB)

Density changes in amorphous Pd{sub 80}Si{sub 20} during ion irradiation below 100K were detected by in situ HVEM measurements of the changes in specimen length as a function of ion fluence. A decrease in mass density as a function of the ion fluence was observed. The saturation value of the change in mass density was determined to be approximately -1.2%.

1994-11-01

183

Consumer density influence in the cost of the rural electric links; A influencia da densidade de consumidores no custo das ligacoes rurais  

Energy Technology Data Exchange (ETDEWEB)

This work shows the influence of the consumer density (density/km) in rural electric networks implementation costs. The analysis of the costs aims the criteria definition for the calculation of the financial involving rates of the rural consumer density. 3 figs., 10 tabs.

1986-12-31

185

Inhomogeneity of electron density in amorphous films  

International Nuclear Information System (INIS)

By the methods of small-angle X-ray scattering and translucent electron microscopy the existence of inhomogeneity of electron density in hydrogenated films of amorphous silicon is confirmed. The decreased density regions are extended and form a branched network of channels oriented mostly by the normal direction to the films surface. The typical size of the decreased density regions network constitutes 10 nm in the 100-800 nm films thickness range. The increase of hydrogen total partial pressure in gas mixture in case of films growth results at first in the decrease of extension of these regions and than to micropores generation in the network nodal points of the decreased electron density regions.

186

Electron momentum density measurements by means of positron annihilation and Compton spectroscopy  

Energy Technology Data Exchange (ETDEWEB)

The electron momentum density is measured applying positron annihilation and Compton spectroscopy in order to get information about electron wave functions. Compton spectroscopic measurements of Pd-Ag and Cu-Zn alloy systems are carried out taking into account crystal structure, mixability, and order state. Three-dimensional momentum densities of silicon are determined in order to get better information about its electronic structure. The momentum density and the spin density of ferromagnetic nickel are investigated using angular correlation curves.

1982-01-01

187

Alpha-particle scattering from Ca-nuclei  

International Nuclear Information System (INIS)

The possibilities, advantages, and difficulties of determining nuclear matter densities by elastic scattering of alpha-particles are generally discussed. On the basis of particular experimental data - 104 MeV alpha-particle scattering from "4"0,"4"2,"4"4,"4"8Ca - a refined folded potential is introduced using a density-dependent alpha-nucleon-interaction and target nucleus densities described by Fourier-Bessel-series. Thereby, the total nucleon densities of these isotopes were determined with little model dependence. The resulting root-mean-square radii and density differences are compared with other experimental results obtained by different methods. (orig.).

1979-07-01

188

A multilayered acoustic hyperlens with acoustic metamaterials  

British Library Electronic Table of Contents (United Kingdom)

The acoustic hyperlens can be realized by an alternating layered structure of water and fluid with negative mass density. Based on this alternating layered principle, we propose that an acoustic metamaterial consisting of three layers in water background can be designed to replace the fluid with negative mass density. The effective mass density and bulk modulus of the system which is composed of acoustic metamaterial and water are functions of the frequency. The effective mass density of such a system is close to the negative mass density of the fluid at a specific frequency; thus an acoustic metamaterial hyperlens can be achieved.

2011-01-01

189

Systematic survey of the design, statistical analysis, and reporting of studies published in the 2008 volume of the Journal of Cerebral Blood Flow and Metabolism  

British Library Electronic Table of Contents (United Kingdom)

Translating experimental findings into clinically effective therapies is one of the major bottlenecks of modern medicine. As this has been particularly true for cerebrovascular research, attention has turned to the quality and validity of experimental cerebrovascular studies. We set out to assess the study design, statistical analyses, and reporting of cerebrovascular research. We assessed all original articles published in the Journal of Cerebral Blood Flow and Metabolism during the year 2008 against a checklist designed to capture the key attributes relating to study design, statistical analyses, and reporting. A total of 156 original publications were included (animal, in vitro, human). Few studies reported a primary research hypothesis, statement of purpose, or measures to safeguard in...

2011-01-01

190

Statistical analyses of coads wind data in coastal regions of the United States  

Energy Technology Data Exchange (ETDEWEB)

In the study, wind data from the Comprehensive Ocean-Atmosphere Data Set (COADS) are used to determine atmospheric circulation changes which are empirically associated with the air temperature changes. Some understanding of the natural processes which produce climate change is anticipated from the study of these associations. Systematic changes of wind in US coastal regions with periods of climate warming and cooling suggest circulation changes, in addition to carbon dioxide-controlled radiation effects, could produce the climate changes indicated by air temperature. A statistical procedure for analyses of COADS was used to determine decade-period vector wind-field differences from the COADS record period. The statistical procedure for these analyses is explained and the wind differences are compared to summaries of mid-Atlantic coast island-station observations.

1992-08-01

191

Response variability in balanced cortical networks  

DEFF Research Database (Denmark)

We study the spike statistics of neurons in a network with dynamically balanced excitation and inhibition. Our model, intended to represent a generic cortical column, comprises randomly connected excitatory and inhibitory leaky integrate-and-fire neurons, driven by excitatory input from an external population. The high connectivity permits a mean field description in which synaptic currents can be treated as gaussian noise, the mean and autocorrelation function of which are calculated self-consistently from the firing statistics of single model neurons. Within this description, a wide range of Fano factors is possible. We find that the irregularity of spike trains is controlled mainly by the strength of the synapses relative to the difference between the firing threshold and the postfiring reset level of the membrane potential. For moderately strong synapses, we find spike statistics very similar to those observed in ...

2006-01-01

192

Cosmic magnification: nulling the intrinsic clustering signal  

CERN Document Server

We investigate the extent to which the pure magnification effect of gravitational lensing can be extracted from galaxy clustering statistics, by a nulling method which aims to eliminate terms arising from the intrinsic clustering of galaxies. The aim is to leave statistics which are free from the uncertainties of galaxy bias. We find that nulling can be done effectively, leaving data which are relatively insensitive to uncertainties in galaxy bias and its evolution, leading to cosmological parameter estimation which is effectively unbiased. This advantage comes at the expense of increased statistical errors, which are in some cases large, but it offers a robust alternative analysis method to cosmic shear for cosmological imaging surveys designed for weak lensing studies, or to full modelling of the clustering signal including magnification effects.

2011-01-01

193

Application of GIS for the evaluation of human exposure to magnetic field in the vicinity of power lines  

Energy Technology Data Exchange (ETDEWEB)

Application of the Geographic Information System (GIS) with a statistical model to evaluate the magnetic field exposure of a population from high-voltage transmission lines near residential areas is discussed, focusing on the interaction of the GIS with the statistical model. In an effort to validate the model measurements of the magnetic field, profiles were taken at two sites and these profiles have been compared with calculated values. Two conclusions have been drawn from the results: (1) the statistical model linked with the GIS is a very powerful tool for the evaluation of exposure of a population to magnetic fields, and (2) success depends on the presence of other sources of magnetic fields and on the exactness of the data used in the model. 4 refs., 5 figs.

1998-10-01

194

Analysis of installation damage tests for LRFD calibration of reinforced soil structures  

British Library Electronic Table of Contents (United Kingdom)

North American design codes are now committed to the development of load and resistance factor design (LRFD) for reinforced soil structures including internal stability limit states. Reliability-based analysis is required to carry out these calibrations. A framework for LRFD calibration has been proposed by the writers that requires bias statistics for load and resistance terms for each limit state function. In this paper the formulation of the limit state for reinforcement tensile rupture is developed and the component strength-reduction bias statistics identified. The paper describes how to compute bias statistics from project-specific installation damage trials for use in reliability-based design for the reinforcement rupture limit state or using data from multiple sources for LRFD cali...

2011-01-01

195

PROBABILISTIC SAFETY ASSESSMENT OF OPERATIONAL ACCIDENTS AT THE WASTE ISOLATION PILOT PLANT  

Energy Technology Data Exchange (ETDEWEB)

This report presents a probabilistic safety assessment of radioactive doses as consequences from accident scenarios to complement the deterministic assessment presented in the Waste Isolation Pilot Plant (WIPP) Safety Analysis Report (SAR). The International Council of Radiation Protection (ICRP) recommends both assessments be conducted to ensure that ''an adequate level of safety has been achieved and that no major contributors to risk are overlooked'' (ICRP 1993). To that end, the probabilistic assessment for the WIPP accident scenarios addresses the wide range of assumptions, e.g. the range of values representing the radioactive source of an accident, that could possibly have been overlooked by the SAR. Routine releases of radionuclides from the WIPP repository to the environment during the waste emplacement operations are expected to be essentially zero. In contrast, potential accidental releases from postulated accident scenarios during waste ...

2000-09-01

196

Characterization of an improved disposal site for low and intermediate level waste using Cs-137 deposition profiles  

International Nuclear Information System (INIS)

According to the present concept, the low and intermediate level wastes generated during the Cernavoda NPP operation will be disposed in a near surface repository. The Saligny site, placed in the NPP protected area, has been proposed for their disposal. Geologically, the main components of this site are the quaternary loess, the Precambrian and Pre-quaternary clays, the Eocene and Barremian limestone. Hydrologically, the site can be divided into a vadose zone down to 45-50 m and three distinct aquifers, two of them in the limestone beds and the third in the lenses of sand and limestone existing in the pre-quaternary clay layer. A large research program for site characterization was initiated in 1996. At present, the site characteristics requested for safety analysis have been experimentally measured on soil samples or calculated by different computer programs. Hundreds of experimental values of the density, porosity, hydraulic conductivity, soil-water retention, ...

2004-09-09

197

Accuracy of patient dose calculation for lung IMRT: A comparison of Monte Carlo, convolution/superposition, and pencil beam computations  

International Nuclear Information System (INIS)

The accuracy of dose computation within the lungs depends strongly on the performance of the calculation algorithm in regions of electronic disequilibrium that arise near tissue inhomogeneities with large density variations. There is a lack of data evaluating the performance of highly developed analytical dose calculation algorithms compared to Monte Carlo computations in a clinical setting. We compared full Monte Carlo calculations (performed by our Monte Carlo dose engine MCDE) with two different commercial convolution/superposition (CS) implementations (Pinnacle-CS and Helax-TMS's collapsed cone model Helax-CC) and one pencil beam algorithm (Helax-TMS's pencil beam model Helax-PB) for 10 intensity modulated radiation therapy (IMRT) lung cancer patients. Treatment plans were created for two photon beam qualities (6 and 18 MV). For each dose calculation algorithm, patient, and beam quality, the following set of clinically relevant dose-volume values was reported: ...

2006-09-01

198

Dependence of ion-induced Pd-silicide formation on nuclear energy deposition density  

Energy Technology Data Exchange (ETDEWEB)

Pd/sub 2/Si formation at the Pd-Si interface induced by irradiation with ions having a wide range of nuclear energy of deposition density has been investigated. It is found that the thickness of the silicide layer formed by irradiation is proportional to the ion fluence for irradiation with ions having low energy-deposition densities, while it is proportional to the square root of the fluence for irradiation with ions having energy-deposition densities. The results indicate that Pd/sub 2/Si formation is reaction limited when the energy-deposition density at the interface is low and is diffusion limited when it is high. The results are compared with the phenomenological theory developed by Horino et al. and it is shown that such a dependence of the limiting processes on the energy depositon density is induced when the diffusion is thermally activated while the reaction at the ...

1986-05-01

199

Density measurements of coal samples by different probe gases and their interrelation  

Energy Technology Data Exchange (ETDEWEB)

Density is useful in deducing the spatial structure of coals. In this paper, nitrogen has been used instead of the commonly employed helium, for the gas displacement pycnometer based density determination of a number of coals of Indian origin. The results show that the nitrogen-based densities are always higher than the helium-based ones. Also, empirical relationships between the helium-based and nitrogen-based coal densities have been developed by two modeling methods, namely, multi-variable regression and artificial neural networks. Although the two models have fared well, the neural network model exhibits a relatively better prediction accuracy and generalization performance than the regression model. This study thus demonstrates that nitrogen, which is cheaper and easily available, can be used gainfully as the probe gas for estimating the true density of coals. 23 refs., 1 fig., ...

2007-07-15

200

Yield improvement for lost mould rapid infiltration forming process by a multistage fractional factorial split plot design  

UK PubMed Central (United Kingdom)

Statistical design of experiments is widely used among scientists and engineers to understand influential factors in a laboratory or manufacturing process. One of the underlying principles of...Full Text Available

2009-07-01

201

Waste Generation and Pollution Prevention Progress Fact Sheet: Oak Ridge National Laboratory  

Energy Technology Data Exchange (ETDEWEB)

This 2-page fact sheet gives statistics on routine waste generation and projected reduction by waste type, and 1994 pollution prevention and recycling accomplishments at ORNL.

1996-09-01

202

Understanding the nature of the statistics behind energy-related CO{sub 2} emissions  

Energy Technology Data Exchange (ETDEWEB)

Research reported here reveals that the reduction of CO{sub 2} emissions into the atmosphere, is mainly dependent on the decrease of the use of fossil fuels, but also on the development of environment-friendly technology and greening of the environment. 2 refs.

2001-07-01

203

The suprachiasmatic nucleus functions beyond circadian rhythm generation  

UK PubMed Central (United Kingdom)

We recently discovered that human activity possesses a complex temporal organization characterized by scale-invariant/self-similar fluctuations from seconds to ~4 hour—statistical properties...Full Text Available

2007-11-09

204

The origins of intensive marine fishing in medieval Europe: the English evidence.  

UK PubMed Central (United Kingdom)

The catastrophic impact of fishing pressure on species such as cod and herring is well documented. However, the antiquity of their intensive exploitation has not been established. Systematic catch statistics...Full Text Available

2004-12-07

205

Statistical properties of nucleotide clusters in DNA sequences*  

UK PubMed Central (United Kingdom)

Using the complete genome of Plasmodium falciparum 3D7 which has 14 chromosomes as an example, we have examined the distribution functions for the amount of C or G and A or T consecutively...Full Text Available

2005-05-01

206

Statistical methods for the blood beryllium lymphocyte proliferation test.  

UK PubMed Central (United Kingdom)

The blood beryllium lymphocyte proliferation test (BeLPT) is a modification of the standard lymphocyte proliferation test that is used to identify persons who may have chronic beryllium disease. A major...Full Text Available

1996-10-01

207

Spontaneous quantal transmitter release: a statistical analysis and some implications  

UK PubMed Central (United Kingdom)

1. Miniature end-plate potentials (m.e.p.p.s) were intra- and extracellularly recorded from neuromuscular junctions in rat phrenic nerve—diaphragm preparations in vitro....Full Text Available

1973-07-01

208

Some food toxic for pets  

UK PubMed Central (United Kingdom)

According to world statistics, dogs and cats are the species that owners most frequently seek assistance with potential poisonings, accounting 95–98% of all reported animal cases. Exposures...Full Text Available

2009-09-01

209

Robust principal axes determination for point-based shapes using least median of squares  

UK PubMed Central (United Kingdom)

A robust technique for determining the principal axes of a 3D shape represented by a point set, possibly with noise, is presented. We use techniques from robust statistics to guide the classical...Full Text Available

2009-04-01

210

Residential magnetic fields and childhood leukemia: a meta-analysis.  

UK PubMed Central (United Kingdom)

OBJECTIVES: This article uses meta-analysis methodology to examine the statistical consistency and importance of random variation among results of epidemiologic studies of residential magnetic field...Full Text Available

1998-12-01

211

Quantification and deconvolution of asymmetric LC-MS peaks using the bi-Gaussian mixture model and statistical model selection  

UK PubMed Central (United Kingdom)

BackgroundLiquid chromatography-mass spectrometry (LC-MS) is one of the major techniques for the quantification of metabolites in complex biological samples. Peak modeling is one...Full Text Available

212

Probabillistic Sensitivity Analysis in Life-Prediction of an alpha + beta Titanium Alloy.  

Science.gov (United States)

Probabilistic sensitivities using the score function method are developed for a lifing analysis of an alpha + beta titanium alloy in a round bar under axial fatigue load. Sensitivities with respect to the statistical inputs of the crack initiation size (a...

2008-01-01

213

Prediction of breast cancer prognosis using gene set statistics provides signature stability and biological context  

UK PubMed Central (United Kingdom)

BackgroundDifferent microarray studies have compiled gene lists for predicting outcomes of a range of treatments and diseases. These have produced gene lists that have little overlap,...Full Text Available

214

Nonlinear time-periodic models of the longitudinal flight dynamics of desert locusts Schistocerca gregaria  

UK PubMed Central (United Kingdom)

Previous studies of insect flight control have been statistical in approach, simply correlating wing kinematics with body kinematics or force production. Kinematics and forces are linked by Newtonian...Full Text Available

2005-06-22

215

Multivariate Non-Normality in the WMAP 1st Year Data  

CERN Document Server

The extraction of cosmological parameters from microwave background observations relies on specific assumptions about the statistical properties of the data, in particular that the p-point distributions of temperature fluctuations are jointly-normal. Using a battery of statistical tests, we assess the multivariate Gaussian nature of the Wilkinson Microwave Anisotropy Probe (WMAP) 1st year data. The statistics we use fall into three classes which test different aspects of joint-normality: the first set assess the normality of marginal (one-point) distributions using familiar univariate methods; the second involves statistics that directly assess joint-normality; and the third explores the evidence of non-linearity in the relationship between variates. We applied these tests to frequency maps, `foreground-cleaned' assembly maps and all-sky CMB-only maps. The assembly maps are of particular interest as ...

2005-01-01

216

Maximization of the connectivity repertoire as a statistical principle governing the shapes of dendritic arbors  

UK PubMed Central (United Kingdom)

The shapes of dendritic arbors are fascinating and important, yet the principles underlying these complex and diverse structures remain unclear. Here, we analyzed basal dendritic arbors of 2,171 pyramidal...Full Text Available

2009-07-28

217

Mapping Drug Physico-Chemical Features to Pathway Activity Reveals Molecular Networks Linked to Toxicity Outcome  

UK PubMed Central (United Kingdom)

The identification of predictive biomarkers is at the core of modern toxicology. So far, a number of approaches have been proposed. These rely on statistical inference of toxicity response from either...Full Text Available

219

Integrity of the tubes used in vertical and horizontal steam generators  

British Library Electronic Table of Contents (United Kingdom)

Statistical data on experience gained from operation of steam generators around the world are presented, problems arising in vertical and horizontal steam generators are described, and the conditions of heattransfer tubes used in them are compared.

2011-01-01

220

Hydrodynamics in an external field  

CERN Document Server

The methods of statistical dynamics are applied to a fluid with 5 conserved fields (the mass, the energy, and the three components of momentum) moving in a given external potential. When the potential is zero, we recover a previously derived system of parabolic differential equations, called "corrections to fluid dynamics".

2002-01-01

221

High order statistical signatures from source-driven measurements of subcritical fissile systems  

Energy Technology Data Exchange (ETDEWEB)

This research focuses on the development and application of high order statistical analyses applied to measurements performed with subcritical fissile systems driven by an introduced neutron source. The signatures presented are derived from counting statistics of the introduced source and radiation detectors that observe the response of the fissile system. It is demonstrated that successively higher order counting statistics possess progressively higher sensitivity to reactivity. Consequently, these signatures are more sensitive to changes in the composition, fissile mass, and configuration of the fissile assembly. Furthermore, it is shown that these techniques are capable of distinguishing the response of the fissile system to the introduced source from its response to any internal or inherent sources. This ability combined with the enhanced sensitivity of higher order signatures indicates that these techniques will be of ...

1998-04-01

222

Evidence for nonrandom hydrophobicity structures in protein chains.  

UK PubMed Central (United Kingdom)

The question of whether proteins originate from random sequences of amino acids is addressed. A statistical analysis is performed in terms of blocked and random walk values formed by binary hydrophobic...Full Text Available

1996-09-03

223

Energy in Lebanon: main conjuncture indicators  

International Nuclear Information System (INIS)

A survey on electric power and on energy balance especially primary and final energy (gas oil, kerosene,solar energy...) has been implemented in Lebanon in 1993. Results and economic impact of energy consumption and energy production are given in statistics and tables. 10 figs.

224

Electric power monthly, July 1995 - with data for April 1995  

Energy Technology Data Exchange (ETDEWEB)

This publication provides statistical data on net generation, fuel consumption, fossil fuel stocks, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on fossil fuel stocks and costs are also included.

1995-07-01

225

Distributions of spontaneous chromosomal aberrations and of spontaneous and induced SCE and micronuclei in peripheral lymphocytes from a human population  

Energy Technology Data Exchange (ETDEWEB)

Biomonitoring of human populations for exposure to genotoxic/clastogenic agents in the environment or the workplace must depend upon statistical tests for elevations in the frequencies of the biological endpoints being monitored, usually chromosomal aberrations (CA), micronuclei (MN), or sister chromatid exchanges (SCE) in peripheral blood lymphocytes. Statistical tests are based, in turn, upon certain assumptions regarding the distribution of the test statistic. When they are often not recognized as such, tests of significance can be in error, and any conclusion drawn that there is or is not a statistically significant difference between one population sample and another maybe erroneous. In population monitoring this means either false negatives or false positives can result and it is hard to know which is worse. Furthermore, even the intelligent design of studies whose object is to test for an ...

1992-12-31

226

Comparison of a minimally invasive procedure versus standard microscopic discotomy: a prospective randomised controlled clinical trial  

UK PubMed Central (United Kingdom)

A Prospective randomised controlled study was done to determine statistical difference between the standard microsurgical discotomy (MC) and a minimally invasive microscopic procedure for disc prolapse...Full Text Available

2009-07-01

227

Classes of small-world networks  

UK PubMed Central (United Kingdom)

We study the statistical properties of a variety of diverse real-world networks. We present evidence of the occurrence of three classes of small-world networks: (a) scale-free networks,...Full Text Available

2000-10-10

228

Chiropteran types I and II interferon genes inferred from genome sequencing traces by a statistical gene-family assembler  

UK PubMed Central (United Kingdom)

BackgroundThe rate of emergence of human pathogens is steadily increasing; most of these novel agents originate in wildlife. Bats, remarkably, are the natural reservoirs of many...Full Text Available

229

CHANDFS2MS - Chandra Deep Field South 2 ... - HEASARC - NASA  

Science.gov (United States)

This table contains point-source catalogs for the ~2 Ms exposure of the Chandra Deep ... Source positions are determined using centroid and matched-filter techniques; .... The 1-sigma upper statistical error (Gehrels 1986, ApJ, 303, ...

230

Biological, Life Course, and Cross-Cultural Studies All point Toward the Value of Dimensional and Developmental Ratings in the Classification of Psychosis  

UK PubMed Central (United Kingdom)

The diagnostic criteria for schizophrenia in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV1)...Full Text Available

2007-07-01

231

Aquatic Resource Monitoring  

Wastenet

...research strategy and plans Aquatic resource monitoring research programs, EMAP and STAR grants Go To EMAP homepage Go To Top Bibliography References for survey designs, statistical analyses , program documentation, and monitoring reports. Reports, abstracts and links to electronic versions Go To Top Frequently Asked Questions ...

232

Applications of BMI or BSI: Differences and Revisions According to Age and Height  

UK PubMed Central (United Kingdom)

Validation of body-mass relationships requires a careful statistical analysis of data of normal weight individuals. BMI (ratio between body mass and square of body height) and BSI values (ratio between...Full Text Available

2010-01-01

233

14 - NASA  

Science.gov (United States)

... and mean rainfall rates, Rm, in the liquid hydrometeor layers using the .... large latitudinal movement of cirrus cloud cover with the changing seasons. ... We study the statistical distribution of PSCs by particle composition using .... the high resolution Cloud Particle Imager (CPI) and standard PMS 2D-C and ...

234

The ideal gases of tachyons  

International Nuclear Information System (INIS)

The formalism of statistical mechanics of particles slower than light has been considered from the point of view of the application of this formalism for the description of tachyons. Properties of ideal gases of tachyons have been discussed in detail. After finding general formulae for quantum, Bose and Fermi gases the classical limit has been considered. It has been shown that Bose-Einstein condensation occurs. The tachyon gas of bosons violates the third principle of thermodynamics. Degenerated Fermi gas has been considered and in this case the entropy vanishes at zero temperature. Difficulties of formulating covariant statistical mechanics have been discussed.

235

Statistical comparison of the effect of relative and absolute humidity on fixed-bed carbon adsorption capacity. Report for January 1987-July 1988  

Energy Technology Data Exchange (ETDEWEB)

This paper describes statistical methods used to evaluate data for toluene (at several typical operating temperatures and humidity levels) and to determine which measure of humidity (relative or absolute) is more important in determining carbon adsorption efficiency. The water content of a solvent-laden stream is critical for its control via carbon adsorption, especially at relative humidities about 50-70%. (Relative humidity is the percent of saturation: absolute humidity is the total water content.)

1989-01-01

236

Security control methods for CEDR  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this document is to summarize the findings of recent studies on the security problem in statistical databases and examine their applicability to the specific needs of CEDR. The document is organized as follows: In Section 2 we describe some general control methods which are available on most commercial database software. In Section 3 we provide a classification of statistical security methods. In Section 4 we analyze the type of users of CEDR and the security control methods which may be applied to each type. In Section 5 we summarize the findings of this study and recommend possible solutions.

1990-09-01

237

Ideal gases of tachyons  

Energy Technology Data Exchange (ETDEWEB)

The formalism of statistical mechanics of particles slower than light has been considered from the point of view of the application of this formalism for the description of tachyons. Properties of ideal gases of tachyons have been discussed in detail. After finding general formulae for quantum, Bose and Fermi gases the classical limit has been considered. It has been shown that Bose-Einstein condensation occurs. The tachyon gas of bosons violates the third principle of thermodynamics. Degenerated Fermi gas has been considered and in this case the entropy vanishes at zero temperature. Difficulties of formulating covariant statistical mechanics have been discussed.

1984-06-11

238

Energy balances of OECD countries 1970/1982  

Energy Technology Data Exchange (ETDEWEB)

The present volume provides standardized energy balance sheets expressed in a common unit of tons of oil equivalent for all OECD Countries. It covers the years 1970 to 1982 year by year and includes many revisions and additions to data previously published. The balances in the present volume are based on data published in OECD Energy Statistics 1971-1981 and OECD Energy Statistics 1981-1982. Tables for each OECD Country include production, import, export, consumption by the different industries, transportation, agriculture, residential sector of the different energies: solid fuels, petroleum, gas, nuclear power and hydroelectricity.

1984-01-01

239

Department of Energy and Climate Change : News Categories : Department of Energy and Climate Change  

Wastenet

...Climate Change : News Categories : Department of Energy and Climate Change Articles in Smart energy meters Results There are 2 articles listed in Smart energy ... meters DECC lays foundations for smart meters rollout A crucial step in delivering the UK's energy security and low carbon future was taken today ...Nuclear Prices Renewable energy Renewable Heat Incentive Saving energy and CO2 Science Smart energy meters Statistics Statistics and projections Transparency Wave and tidal Wind ...

240

Damage to rotor blades in axial steam turbines  

International Nuclear Information System (INIS)

A statistical evaluation of rotor blade damage in axial steam turbines affords an insight into the extent of the repair costs incurred and reveals the types of defects and shortcomings which cause such damage. The great amount of rotor blade damage discovered during control inspections will surprise even many turbine experts. The statistical evaluation is followed by a review of the more frequent causes of damage and their characteristic features, illustrated on the basis of practical examples. This contribution is intended as an aid to both the manufacturers and operators of steam turbines in preventing the oft almost classic types of faults which constantly recur. (orig.).

241

Correlation-based spectral clustering for flexible process monitoring  

British Library Electronic Table of Contents (United Kingdom)

The individuality of production devices should be taken into account when statistical models are designed for parallelized devices. In the present work, a new clustering method, referred to as NC-spectral clustering, is proposed for discriminating the individuality of production devices. The key idea is to classify samples according to the differences of the correlation among measured variables, since the individuality of production devices is expressed by the correlation. In the proposed NC-spectral clustering, the nearest correlation (NC) method and spectral clustering are integrated. The NC method generates the weighted graph that expresses the correlation-based similarities between samples, and the constructed graph is partitioned by spectral clustering. A new statistical process monit...

2011-01-01

242

An experimental and molecular-statistical study of the adsorption of the iodobenzene, 2-iodothiophene, and isomeric iodoadamantane molecules on the graphite basal face surface  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption of iodobenzene, 2-iodothiophene, and 1- and 2-iodoadamantanes on the surface of graphitized thermal carbon black were determined experimentally. The influence of the special features of the molecular structure of the adsorbates on the thermodynamic characteristics of adsorption was studied. The atom-atom approximation of the semiempirical molecular-statistical theory of adsorption was used to calculate the thermodynamic characteristics of adsorption of the adsorbates using the newly determined potential function parameters of pair intermolecular interaction (?(r)) of I with C atoms of the basal graphite face. For the example of isostructural monohalogenated benzenes, thiophenes, and adamantanes, a comparative analysis of the contributions of ...

2011-01-01

243

chipD: a web tool to design oligonucleotide probes for high-density tiling arrays  

UK PubMed Central (United Kingdom)

chipD is a web server that facilitates design of DNA oligonucleotide probes for high-density tiling arrays, which can be used in a number of genomic applications such as ChIP-chip or gene-expression...Full Text Available

2010-07-01

244

Zoledronate to Preserve Bone Mineral Density  

Science.gov (United States)

Phase II Randomized Study of the Effect of Zoledronate Versus Observation on Bone Mineral Density of the Lumbar Spine in Patients Undergoing Risk-Reducing Excision of Both Ovaries (GOG-0215). See the protocol summary.

245

Sodium sulphur starts to deliver. [High power density battery  

Energy Technology Data Exchange (ETDEWEB)

The development of a high power density sodium sulphur battery with a five-year maintenance-free life is described. These batteries are likely to be used in industrial trucks, milk floats, electric cars, storing power station output and power for satellites. (U.K.).

1985-10-03

246

Resolving Individuals Contributing Trace Amounts of DNA to Highly Complex Mixtures Using High-Density SNP Genotyping Microarrays  

UK PubMed Central (United Kingdom)

We use high-density single nucleotide polymorphism (SNP) genotyping microarrays to demonstrate the ability to accurately and robustly determine whether individuals are in a complex genomic DNA mixture....Full Text Available

2008-08-01

247

Phonon density of states in V_3Si  

International Nuclear Information System (INIS)

The observation by inelastic neutron scattering techniques of a high energy peak in the phonon spectrum (14 THz) of V_3Si is reported, and is attributed to a peak in the phonon density of states due to vanadium motions by the incoherent inelastic neutron scattering process.

1988-12-01

248

On the temperature dependence of the level density parameter and its effect upon neutron evaporation spectra  

Energy Technology Data Exchange (ETDEWEB)

Effects associated with the temperature dependence of the level density parameter, a(T), are investigated in connection with neutron evaporation processes. Different approximations, for this temperature dependence, are compared for the case of neutron emission from the compound nucleus /sup 209/Pb.

1987-07-01

249

Measurements of Spectral Characteristics of Swimmer Targets ...  

Science.gov (United States)

... 3.0 Radar Measurements 3-1 3. 1 Spectral Density Measurements 3-2 3. 1. 1 System Calibration 3-3 ... 3. 1 SPECTRAL DENSITY MEASUREMENTS ...

1974-05-01

250

Hardness, density, and shrinkage characteristics of silk-oak from ...  

Science.gov (United States)

Sep 1, 2011 ... Title: Hardness, density, and shrinkage characteristics of silk-oak from Hawaii. Author: Youngs, R. L.. Date: 1964. Source: Research note FPL ...

251

Guided Cell Migration on Microtextured Substrates with Variable Local Density and Anisotropy  

UK PubMed Central (United Kingdom)

This work reports the design of and experimentation with a topographically patterned cell culture substrate of variable local density and anisotropy as a facile and efficient platform to guide...Full Text Available

2009-02-06

252

Examining the Phonological Neighborhood Density Effect Using Near Infrared Spectroscopy  

UK PubMed Central (United Kingdom)

Phonological density refers to the number of words that can be generated by replacing a phoneme in a target word with another phoneme in the same position. Although the precise nature of the...Full Text Available

2011-09-01

253

Energy-resolved electron particle and energy fluxes in positive column plasmas  

Energy Technology Data Exchange (ETDEWEB)

This paper deals with electron flux densities and electron energy flux densities in positive column discharges. Recent kinetic calculations by Uhrlandt and Winkler have revealed the interesting physical phenomenon of radially inward directed energy flux densities in positive column plasmas. We have used a self-consistent positive column model, based on an accurate and highly detailed Monte Carlo code, to study this effect in more depth. The results of this study show a rather complex physical picture of electron particle and energy flux densities. Electrons with low energies usually exhibit radially outward directed particle and energy flux densities. At energies above the threshold for electronic excitation particle and energy flux densities are usually inward directed. Only close to the wall, at total energies above the wall potential energy, do these flux ...

1999-11-07

254

Effects of calcium supplementation on bone density in healthy children: meta-analysis of randomised controlled trials  

UK PubMed Central (United Kingdom)

Objectives To assess the effectiveness of calcium supplementation for improving bone mineral density in healthy children and to determine if any effect is modified by other factors and...Full Text Available

2006-10-14

255

Effects of Depot Medroxyprogesterone Acetate and 20 ?g Oral Contraceptives on Bone Mineral Density  

UK PubMed Central (United Kingdom)

OBJECTIVEHormonal contraceptives may adversely affect bone mineral density . However, racial differences and the reversibility of these changes are poorly understood....Full Text Available

2008-10-01

256

Development of compression-controlled low-level laser probe system: towards clinical application  

UK PubMed Central (United Kingdom)

Various physico-chemical tissue optical clearing (TOC) methods have been suggested to maximize photon density in tissue. In order to enhance photon density, a compression-controlled low-level...Full Text Available

2010-09-01

257

Determination of Thermal Properties and Morphology of Eucalyptus Wood Residue Filled High Density Polyethylene Composites  

UK PubMed Central (United Kingdom)

Thermal behaviors of eucalyptus wood residue (EWR) filled recycled high density polyethylene (HDPE) composites have been measured applying the thermogravimetric analysis (TGA) and differential scanning...Full Text Available

258

Cell-density-dependent Changes in the Metabolism of Chloronema Cell Cultures  

UK PubMed Central (United Kingdom)

In the growing chloronema cell suspension cultures of the moss Funaria hygrometrica Hedw., activities of several enzymes have been found to be cell-density-dependent. Cyclic nucleotide...Full Text Available

1979-07-01

259

Buoyant Densities and Dry-Matter Contents of Microorganisms: Conversion of a Measured Biovolume into Biomass  

UK PubMed Central (United Kingdom)

Several isolates of bacteria and fungi from soil, together with cells released directly from soil, were studied with respect to buoyant density and dry weight. The specific volume (cubic centimeters...Full Text Available

1983-04-01

260

Association between intratumoral lymphatic microvessel density (LMVD) and clinicopathologic features in endometrial cancer: a retrospective cohort study  

UK PubMed Central (United Kingdom)

BackgroundLymph node metastasis in endometrial cancer significantly decreases survival rate. Few data on the influence of intratumoral lymphatic microvessel density (LMVD) on survival...Full Text Available

261

An automated procedure for detecting protein folds from sub-nanometer resolution electron density  

UK PubMed Central (United Kingdom)

The use of sub-nanometer resolution electron density as spatial constraints for denovo and ab-initio structure prediction requires knowledge of protein boundaries...Full Text Available

2010-06-01

262

Theoretical study of the phonon properties of SrS  

International Nuclear Information System (INIS)

Using an ab initio pseudopotential method within a generalized gradient approximation of the density functional theory, the structural, electronic, and phonon properties of SrS in the B1 (NaCl) and B2 (CsCl) structures have been studied. The calculated lattice constants, static bulk modulus, and first-order pressure derivative of the bulk modulus are reported for both the B1 and B2 structures and compared with previous experimental and theoretical calculations. Electronic band structures and densities of states have been derived for SrS. Subsequently, a linear-response approach to the density functional theory is used to derive the phonon frequencies and densities of states.

2009-05-25

263

The Calculation and Measurement of Flexural and ...  

Science.gov (United States)

... Verheij (1980) described how the frequency domain could be exploited using cross spectral density measurements to measure the flexural ...

1996-02-01

265

Plasma Dynamics in the Vicinity of the Local Plasma resonance Point Excited by Pumping Electric Field or Modulated Electron Beam  

International Nuclear Information System (INIS)

Excitation of the HF electric field in the local plasma resonance region (LPRR) of inhomogeneous plasma by pumping electric field or modulated electron beam results to appearance of the ponderomotive force that presses plasma out of this region. Density cavity is formed in the LPRR due to this field. Further dynamics in this region depends on the plasma properties. For plasma with hot electrons ion-acoustic pulses run away from the cavity. at the local density maximum the new peak of electric field is excited. It results to the formation of new density cavity, etc. For isothermal plasma the density jump is formed.

2006-01-01

266

Physical and Computational Investigation of the Wall Pressure ...  

Science.gov (United States)

... Although other authors had made cross-spectral density measurements, Corcos pointed to the importance of this function as indicative of the true ...

1990-04-26

267

Nuclear structure physics at high resolution  

Energy Technology Data Exchange (ETDEWEB)

Techniques for studying nuclear structure are reviewed. Examples are given of charge density determinations by electron and proton inelastic scattering. (AIP)

1985-04-01

275

E2 transition densities and proton shell structure in /sup 88/Sr, /sup 89/Y, and /sup 90/Zr  

Energy Technology Data Exchange (ETDEWEB)

Electron scattering data have been used to obtain transition charge densities for the low-lying E2 transitions in /sup 88/Sr, /sup 89/Y, and /sup 90/Zr. These charge densities show a characteristic shape indicative of their microscopic constituency, modified by core-polarization effects. A good description of transitions in the even-even nuclei is obtained by using the measured single-particle transitions in /sup 89/Y as effective densities. .ID LV2086 .PG 19 22

1983-01-03

276

Development of a topology optimization program considering density and homogeni-zation methods  

British Library Electronic Table of Contents (United Kingdom)

In most previous studies of topology optimization, commercial programs, such as Optistruct, ANSYS, and MSC Patran, usually were used during implementation. Such commercial programs are not easy to use and entail time and cost. In addition, it is difficult to confirm results with reference to individual stages of optimization. For addressing this disadvantage, a topology optimization program, which is based on the C language, is developed in this study. This is a very convenient and powerful program for users to conduct topology optimization by using all density methods and homogenization methods in compliance with the methodology. For verifying the developed program, first of all, topology optimization was implemented by using density methods to evaluate the strain energy density of a cant...

2011-01-01

277

Development and Calibration of Two and Four Wire Water ...  

Science.gov (United States)

... measurement. Power spectral density measurements are made by the dynamic signal analyzer for each channel. A cross power ...

1992-12-01

278

DEVELOPMENT OF A TUNED DAMPER TO REDUCE ...  

Science.gov (United States)

... Since power spectral density measurements are the result of a statisti- cal sampling process, as are the probability measurements, we now ...

1967-09-01

279

Cosmic ray density gradients perpendicular to the solar equatorial plane  

Energy Technology Data Exchange (ETDEWEB)

It is noted that the existence of cosmic-ray semidiurnal anisotropy of interplanetary origin has generally been attributed to the symmetrically rising density gradients perpendicular to the solar equatorial plane. An increase in the magnitude of the semidiurnal anisotropy of cosmic rays during the years 1973-1975 by a factor of 2 is in theory expected to be associated with larger magnitudes of the heliolatitudinal density gradients. The distribution of cosmic-ray intensity in the heliolatitude range + or - 7.25 deg obtained using the data of the Deep River neutron monitor is shown not to support the density gradient hypothesis. The presence of symmetrical gradients at higher heliolatitudes, however, cannot be ruled out.

1982-08-01

280

Coefficient of Variation Spectral Analysis: An Application to ...  

Science.gov (United States)

... A major problem in the analysis of power spectral density measurements is distinguishing between narrowband spectral components of interest ...

1983-05-03

282

A GENERAL STUDY OF PROCESSES FOR THE ...  

Science.gov (United States)

... fields, materials can be subjected to energy densities exceeding those realized in high explosives, a fact which forms the basis for magnetic forming ...

1962-11-01

283

Quantitative 31P NMR Spectroscopy and 1H MRI Measurements of Bone Mineral and Matrix Density Differentiate Metabolic Bone Diseases in Rat Models  

UK PubMed Central (United Kingdom)

In this study, bone mineral density (BMD) of normal (CON), ovariectomized (OVX) and partially nephrectomized (NFR) rats was measured by 31P NMR spectroscopy; bone matrix density was...Full Text Available

2010-06-01

284

On the Improved Plasma Confinement in Toroidal Systems. Measuring of the Plasma Density Inhomogeneities Near the Gas Valve  

International Nuclear Information System (INIS)

Comparison of plasma density increase was carried out in outer and inner channels of the interferometer in T-11M tokamak. There were two cases of gas puffing: by outer valve or upper one. Amplitude of difference of the plasma density increase consisted of 9% near the outer valve. Perturbation of the electric potential e?1/Te can have similar value. This perturbation can lead to appearance of the additional losses.

2006-01-01

285

Nuclear level densities in self-consistent field approximation  

International Nuclear Information System (INIS)

The effect of two-body nature of the nuclear shell model potential on the recent numerical calculations of the nuclear level density has been examined. For the two most widely used single particle energy level schemes based on harmonic oscillator and Woods-Saxon potential, this effect is shown to significantly modify the excitation energy dependence of the level densities. (author).

1976-01-01

286

IAEA advisory group meeting on basic and applied problems of nuclear level densities  

International Nuclear Information System (INIS)

Separate entries were made in the data base for 17 of the 19 papers included. Two papers were previously included in the data base. Workshop reports are included on (1) nuclear level density theories and nuclear model reaction cross-section calculations and (2) extraction of nuclear level density information from experimental data.

1983-04-11

287

IAEA advisory group meeting on basic and applied problems of nuclear level densities  

Energy Technology Data Exchange (ETDEWEB)

Separate entries were made in the data base for 17 of the 19 papers included. Two papers were previously included in the data base. Workshop reports are included on (1) nuclear level density theories and nuclear model reaction cross-section calculations and (2) extraction of nuclear level density information from experimental data. (WHK)

1983-06-01

288

Fault diagnosis of rolling bearing based on cyclic spectrum density  

International Nuclear Information System (INIS)

The paper considered the vibration signals of rotating equipment as cyclo stationary signals through analyzing the features of this kind of signals. Based on the analytic method of cyclic spectrum density, the paper pointed out that the impact frequency could be extracted effectively with the help of scanning cyclic frequency domain. The validity of the method of cyclic spectrum density is proved by simulating signals and the method is applied to the diagnosis of rolling bearings. (authors)

2009-09-01

289

Dynamical evolution and molecular abundances of interstellar clouds  

International Nuclear Information System (INIS)

Dynamical models are presented that start with interstellar gas in an initial diffuse state and consider their gravitational collapse and the formation of dense cores. Frozen-in tangled magnetic fields are included to mimic forces that might oppose gravitational contraction and whose effectiveness may increase with increasing core densities. Results suggest the possibility that dense cloud cores may be dynamically evolving ephemeral objects, such that their lifespan at a given core density decreases as that density increases. 66 refs.

290

Density of Different Substances 7th Grade Standard I Obj. 2  

Science.gov (United States)

In this lesson you will learn about density and why some things float and others sink. Imagine you and a friend are on a camping trip. As you walk along a stream, your friend notices some shiny gold rocks. You pick them up wondering if they are real gold nuggets. Your friend remembers there is a mineral that looks like gold, "fools gold", or pyrite. The density of ...

2008-11-07

291

Contribution of the ion-energy distribution to the current-density distribution of a focused-ion beam  

Energy Technology Data Exchange (ETDEWEB)

A general expression for the current-density distribution of a focused-ion beam (FIB) in the chromatic-aberration region is set up in the form of a definite integral. With the experimentally obtained ion-energy distribution of a liquid-metal ion source, its contribution to the FIB current-density distribution is estimated. Calculated results explain the wide-exponential tail of a FIB.

1987-09-01

292

Contribution of the ion-energy distribution to the current-density distribution of a focused-ion beam  

International Nuclear Information System (INIS)

A general expression for the current-density distribution of a focused-ion beam (FIB) in the chromatic-aberration region is set up in the form of a definite integral. With the experimentally obtained ion-energy distribution of a liquid-metal ion source, its contribution to the FIB current-density distribution is estimated. Calculated results explain the wide-exponential tail of a FIB.

293

Consistent Loop Quantum Cosmology  

CERN Document Server

A consistent combination of quantum geometry effects rules out a large class of models of loop quantum cosmology and their critical densities as they have been used in the recent literature. In particular, the critical density at which an isotropic universe filled with a free, massless scalar field would bounce must be well below the Planck density. In the presence of anisotropy, no model of the Schwarzschild black hole interior analyzed so far is consistent.

2008-01-01

294

What density-functional theory can tell us about the spin-density wave in  

International Nuclear Information System (INIS)

The energy-versus-volume curve of the spin-density wave (SDW) in body-centred-cubic Cr is calculated with the density functional theory/full-potential linearized augmented plane wave (DFT/FLAPW) method using the generalized gradient approximation (GGA). The predicted ground state is not the SDW, in contrast to an earlier FLAPW calculation. A conjecture is formulated that the widely varying results of the local density approximation (LDA) and GGA - and of different solution methods - can be scaled by the size of the calculated moment. As a consequence, experimentally relevant properties of the SDW can be calculated by tuning the moment. The implications of these results for the ability of DFT to describe Cr are discussed. (author)

2002-04-01

295

The structure of an active acoustic metamaterial with tunable effective density  

Energy Technology Data Exchange (ETDEWEB)

A new class of one-dimensional active acoustic metamaterials (AAMMs) with programmable effective densities is presented. The proposed AAMM is capable of producing densities that are orders of magnitudes lower or higher than the ambient fluid. Such characteristics are achieved by using an array of fluid cavities separated by piezoelectric diaphragms that are controlled to generate constant densities over wide frequency bands. The piezodiaphragms are augmented with passive electrical components to broaden the operating frequency bandwidth and enable densities higher than the fluid medium to be generated. The use of these components is shown to be essential to maintain the closed-loop compliance of the piezodiaphragm away from the zone of elastic instabilities. The values of the passive components are selected on a rational basis in order to ensure a balance between the frequency bandwidth and control ...

2009-12-15

296

The dark matter halos of Draco and Ursa Minor  

International Nuclear Information System (INIS)

Published density profiles and central velocity dispersions place important constraints on the stellar velocity ellipsoid and on the distribution of dark matter (DM) in the dwarf spheroidal galaxies Draco and Ursa Minor. Central velocity dispersions of 9 km/s are adopted for Draco and 11 km/s for Ursa Minor. Then, for an isotropic stellar velocity distribution, the central DM densities are 0.8 and 1.0 solar mass/cu pc, respectively, if visible and dark matter have the same core radius. If DM has a much larger core radius than visible matter but nevertheless dominates the potential, these densities are reduced by a factor of 2. Central DM densities can be lower than this only if the stellar velocity distribution is anisotropic. Simple two-component King models are used to investigate this and to look for the smallest DM densities that are consistent with the observations. 36 refs.

297

The Concentration-Density Relation of Galaxies in Las Campanas Redshift Survey  

CERN Document Server

We report the results of the evaluation of the ``concentration-density'' relation of galaxies in the local universe, taking advantage of the very large and homogeneous data set available from the Las Campanas Redshift Survey (Shectman et al. 1996). This data set consists of galaxies inhabiting the entire range of galactic environments, from the sparsest field to the densest clusters, thus allowing us to study environmental variations without combining multiple data sets with inhomogeneous characteristics. Concentration is quantified by the automatically-measured concentration index $C$, which is a good measure of a galaxy's bulge-to-disk ratio. The environment of the sample galaxies is characterized both by the three-space local galaxy density and by membership in groups and clusters. We find that the distribution of C in galaxy populations varies both with local density and with cluster/group membership: the fraction of ...

1999-01-01

298

Response of native ungulates to drought in semi arid Kenyan rangeland  

British Library Electronic Table of Contents (United Kingdom)

Abstract The distribution and abundance of native ungulates were measured on commercially managed, semi arid rangeland in central Kenya over a 3 year period that encompassed severe drought and above average rainfall. Native ungulate biomass density averaged 5282 kg km 2 over the study and was dominated by elephant (Loxodonta africana), impala (Aepyceros melampus) and dik dik (Madoqua kirkii). Biomass density of domestic cattle (Bos taurus) averaged 2280 kg km 2 during the study. Responses of native ungulates to severe drought were variable. Impala densities were similar to or greater than densities for similar habitat in protected areas, and varied from 12 to 16 km 2 during and following the drought to 24 29 km 2 following above average rainfall. Dik dik densities were also greater than de...

2010-01-01

299

Native Synthetic Imaging of Smoothed Particle Hydrodynamics density fields using gridless Monte Carlo Radiative Transfer  

CERN Document Server

An algorithm for creating synthetic telescope images of Smoothed Particle Hydrodynamics (SPH) density fields is presented, which utilises the adaptive nature of the SPH formalism in full. The imaging process uses Monte Carlo Radiative Transfer (MCRT) methods to model the scattering and absorption of photon packets in the density field, which then exit the system and are captured on a pixelated image plane, creating a 2D image (or a 3D datacube, if the photons are also binned by their wavelength). The algorithm is implemented on the density field directly: no gridding of the field is required, allowing the density field to be described to an identical level of accuracy as the simulations that generated it. Some applications of the method to star and planet formation simulations are presented to illustrate the advantages of this new technique, and suggestions as to how this framework could support a ...

2010-01-01

300

Mass density of glassy Pd{sub 80}Si{sub 20}during low temperature light ion irradiation.  

Energy Technology Data Exchange (ETDEWEB)

Changes in mass density of amorphous Pd{sub 80}Si{sub 20} were monitored in situ during irradiation with He{sup 2+} and H{sup +} ions at temperatures below 100 K and during subsequent thermal treatment. The mass density decreased with increasing ion fluence and exponentially approached a saturation value of -1.2%, corresponding to a recombination volume of 190 atomic volumes. The initial swelling rate was 2.3 atomic volumes/displaced atom. The mass density of the irradiated material increased during subsequent thermal treatment, and the irradiation-induced decrease of the mass density recovered completely at room temperature.

2001-10-01

301

Locally resonant acoustic metamaterials with 2D anisotropic effective mass density  

British Library Electronic Table of Contents (United Kingdom)

A two-dimensional (2D) lattice model with anisotropic resonant microstructures is found to provide an anisotropic band gap structure. A 2D continuum with anisotropic effective mass density is introduced to represent this lattice system. Two methods are proposed to derive the equivalent continuum. In the first method, the effective mass density of the equivalent continuum is obtained by matching the dispersion relations for harmonic waves propagating in the principal directions. The second approach employs an approximate estimation of the effective mass density by volume-averaging an effective mass that represents the resonant microstructure. For both equivalent continuum models, the effective mass density is frequency-dependent and may become negative in certain frequency ranges. Subsequen...

2011-01-01

302

A study of binary mixture boiling: boiling site density and subcooled heat transfer  

Energy Technology Data Exchange (ETDEWEB)

(Boiling site densities and heat-transfer coefficients have been measured for ethanol-water and ethanol-benzene mixtures at 1.01 bar for a heated vertical brass disk. A strong effect of composition on the boiling site density was observed, which was attributed to the nature of the activation of the boiling surface and mass diffusion effects. The boiling heat-transfer coefficient was found to decrease with increasin subcooling, but for the mixtures at a given level of subcooling the decrease was less than that for the single components and azeotropic mixtures.) The heat-transfer coefficient at a given heat flux was seen to be quite insensitive to the very large increase in boiling site density in comparing the pure water and the ethanol-water azeotrope results, leading one to question pool boiling models that predict heat-transfer rates on the basis of boiling site density.

1985-05-01

303

A numerical study of ultra-short-pulse reflectometry  

Energy Technology Data Exchange (ETDEWEB)

Ultra-short-pulse reflectometry is studied by means of the numerical integration of a one-dimensional full-wave equation for ordinary modes propagating in a plasma. The numerical calculations illustrate the potential of using the reflection of ultra-short-pulse, microwaves as an effective probe of the density profile even in the presence of significant density fluctuations. The difference in time delays of differing frequency components of the microwaves can be used to deduce the density profile. The modification of the reflected pulses in the presence of density fluctuations is examined and can be understood based on considerations of Bragg resonance. A simple and effective profile-reconstruction algorithm using the zero-crossings of the reflected pulse and subsequent Abel inversion is demonstrated. The robustness of the profile reconstruction algorithm in the presence of a sufficiently small amplitude ...

1994-05-01

304

The validity of the density scaling method in primary electron transport for photon and electron beams  

International Nuclear Information System (INIS)

In the convolution/superposition method of photon beam dose calculations, inhomogeneities are usually handled by using some form of scaling involving the relative electron densities of the inhomogeneities. In this paper the accuracy of density scaling as applied to primary electrons generated in photon interactions is examined. Monte Carlo calculations are compared with density scaling calculations for air and cork slab inhomogeneities. For individual primary photon kernels as well as for photon interactions restricted to a thin layer, the results can differ significantly, by up to 50%, between the two calculations. However, for realistic photon beams where interactions occur throughout the whole irradiated volume, the discrepancies are much less severe. The discrepancies for the kernel calculation are attributed to the scattering characteristics of the electrons and the consequent oversimplified modeling used in the ...

305

Resilience of the current density distribution with respect to changes of the electron density profile in tokamak discharges  

International Nuclear Information System (INIS)

The relationship between the current density distribution and the electron density profile during the flat-top phase of Ohmic discharges in TEXTOR has been investigated by means of far-infrared interferometry and polarimetry. It is found that neither gradual nor rapid changes of the electron density distribution (induced by continuous gas feed or pellet injection) alter the current profile significantly. The conclusion is drawn from the temporal evolution of the measured Faraday rotation signals #alpha#_e_x_p(x,t) which are proportional to the line integrals of n_c times the poloidal magnetic field component B_p_c along the probing beam paths (x is the distance of a chord from the plasma centre). By taking into account the known variation of the density profile but keeping the current distribution fixed, theoretical signals #alpha#_s_i_m(x,t) can be calculated which match the observed waveforms very ...

306

Dynamic mass density and acoustic metamaterials  

Energy Technology Data Exchange (ETDEWEB)

Mass density of a composite is generally taken as the volume-averaged value of components' densities. Moreover, the same volume-averaged mass density is usually used to calculate the wave speed in the long-wavelength limit, i.e., where the wavelength is much larger than the size of the inhomogeneities. In this paper, we show via rigorous derivation that the dynamic mass density used in the calculation of (long-wavelength) wave speed can differ significantly from the static volume-averaged value. This recognition is shown to yield an excellent account of some recent experimental data, as well as to make possible the realization of acoustic metamaterials. Physical reason for the difference between two mass densities is attributed to the relative motion between the components. That is, the implicit assumption-that all components in a composite must move uniformly in the ...

2007-05-15

307

[sup 123]I-MIBG myocardial scintigraphy in diabetic patients. Relationship with [sup 201]Tl uptake and cardiac autonomic function  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this paper is to investigate the influence of diabetic myocardial damage (suspected myocardial damage; SMD) diagnosed by [sup 201]Tl-SPECT and diabetic cardiac autonomic neuropathy (AN) on myocardial MIBG uptake in patients with NIDDM. Eighty-seven diabetic patients divided into four subgroups: 23 with SMD (+) AN (+); 19 with SMD (+) AN (-); 27 with SMD (-) AN (+); 18 with SMD (-) AN (-), and 10 controls were studied. Both planar and SPECT images were taken at 30 minutes (early) and 3 hours (delayed) after [sup 123]I-MIBG injection. The heart to mediastinum uptake ratio (H/M) and washout ratio of [sup 123]I-MIBG (WR) were obtained from both planar images. Similarly, the difference between the [sup 201]Tl image and the [sup 123]I-MIBG image in the total uptake score (TUS) was taken as the difference in the total uptake score ([Delta]TUS) representing cardiac sympathetic denervation without SMD. On both early and delayed planar images, the mean H/M value in the subgroups ...

1998-12-01

308

Transportation energy data book: Edition 12  

Energy Technology Data Exchange (ETDEWEB)

The Transportation Energy Data Book: Edition 12 is a statistical compendium prepared and published by Oak Ridge National Laboratory under contract with the Office of Transportation Technologies in the Department of Energy. Designed for use as a desk-top reference, the data book represents an assembly and display of statistics and information that characterize transportation activity, and presents data on other factors that influence transportation energy use. The purpose of this document is to present relevant statistical data in the form of tables and graphs. Each of the major transportation modes--highway, air, water, rail, pipeline--is treated in separate chapters or sections. Chapter 1 compares US transportation data with data from seven other countries. Aggregate energy use and energy supply data for all modes are presented in Chapter 2. The highway mode, which accounts for over three-fourths of total transportation ...

1992-03-01

309

Survey design, statistical analysis, and basis for statistical inferences in coastal habitat injury assessment: Exxon Valdez oil spill  

Energy Technology Data Exchange (ETDEWEB)

The objective of the Coastal Habitat Injury Assessment study was to document and quantify injury to biota of the shallow subtidal, intertidal, and supratidal zones throughout the shoreline affected by oil or cleanup activity associated with the Exxon Valdez oil spill. The results of these studies were to be used to support the Trustee`s Type B Natural Resource Damage Assessment under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). A probability based stratified random sample of shoreline segments was selected with probability proportional to size from each of 15 strata (5 habitat types crossed with 3 levels of potential oil impact) based on those data available in July, 1989. Three study regions were used: Prince William Sound, Cook Inlet/Kenai Peninsula, and Kodiak/Alaska Peninsula. A Geographic Information System was utilized to combine oiling and habitat data and to select the probability sample of study sites. Quasi-experiments were ...

1995-12-31

310

Proper Assessment of the JFK Assassination Bullet Lead Evidence from Metallurgical and Statistical Perspectives  

Energy Technology Data Exchange (ETDEWEB)

The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano, 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in Mannlicher-Carcano bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in ...

2006-08-29

311

Epidemiologic investigation of health effects in Air Force personnel following exposure to herbicides. Summary mortality update, 1989. Interim report 1979-1987  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the Air Force Health Study is to determine whether those individuals involved in the spraying of herbicides in Vietnam during the Ranch Hand operation have experienced any adverse health effects as a result of their participation in that program. The study is designed to evaluate both the mortality (death) and morbidity (disease) in these individuals over a 20-year beginning in 1982. The Baseline Mortality Report was released in June 1983, the Baseline Morbidity Report in February 1984. Follow-up mortality reports were released in 1984, 1985, and 1986. This study has not demonstrated health effects which can be conclusively attributed to herbicide or dioxin exposure. This report contains analyses of cumulative deaths occurring up to 31 December 1987. The overall cumulative mortality of the Ranch Hands remains statistically indistinguishable from that of both their matched Comparisons and the entire Comparison, population, although there is a ...

1989-04-17

312

Entanglement Spectrum of a Disordered Topological Chern Insulator  

CERN Document Server

How much information is stored in the ground-state of a system without \\emph{any symmetry} and how can we extract it? This question is investigated by analyzing the behavior of a topological Chern Insulator (CI) in the presence of disorder, with a focus on its entanglement spectrum (EtS) constructed from the ground state. For systems with symmetries, the EtS was shown to contain explicit information revealed by sorting the EtS against the conserved quantum numbers. In the absence of any symmetry, we demonstrate that statistical methods such as the level statistics of the EtS can be equally insightful, allowing us to distinguish when an insulator is in a topological or trivial phase and to map the boundary between the two phases, where EtS becomes entirely delocalized. The phase diagram of a CI is explicitly computed as function of Fermi level ($E_F$) and disorder strength using the level statistics of the EtS and energy ...

2010-01-01

313

Electric power monthly: October 1995, with data for July 1995  

Energy Technology Data Exchange (ETDEWEB)

The Electric Power Monthly (EPM) presents monthly electricity statistics for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. The Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy prepares the EPM. This publication provides monthly statistics at the State, Census division, and US levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are ...

1995-10-19

314

Electric power monthly, December 1997 with data for September 1997  

Energy Technology Data Exchange (ETDEWEB)

The Electric Power Monthly (EPM) presents monthly electricity statistics for a wide audience including congress, Federal and State agencies, the electric utility industry, and the general public. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead. This publication provides monthly statistics at the State, Census division, and US levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity retail sales, associated revenue, and average revenue per kilowatthour of electricity sold. In addition, data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net ...

1997-12-01

315

CAA broadband noise prediction for aeroacoustic design  

Science.gov (United States)

The current status of a computational aeroacoustics (CAA) approach to simulate broadband noise is reviewed. The method rests on the use of steady Reynolds averaged Navier-Stokes (RANS) simulation to describe the time-averaged motion of turbulent flow. By means of synthetic turbulence the steady one-point statistics (e.g. turbulence kinetic energy) and turbulent length- and time-scales of RANS are translated into fluctuations having statistics that very accurately reproduce the initial RANS target-setting. The synthetic fluctuations are used to prescribe sound sources which drive linear perturbation equations. The whole approach represents a methodology to solve statistical noise theory with state-of-the-art CAA tools in the time-domain. A brief overview of the synthetic turbulence model and its numerical discretization in terms of the random particle-mesh (RPM) and fast random particle-mesh (FRPM) method is given. Results ...

2011-08-01

316

Analysis of Spatio-Temporal Preferences and Encounter Statistics for DTN Performance  

CERN Document Server

Spatio-temporal preferences and encounter statistics provide realistic measures to understand mobile user's behavioral preferences and transfer opportunities in Delay Tolerant Networks (DTNs). The time dependent behavior and periodic reappearances at specific locations can approximate future online presence while encounter statistics can aid to forward the routing decisions. It is theoretically shown that such characteristics heavily affect the performance of routing protocols. Therefore, mobility models demonstrating such characteristics are also expected to show identical routing performance. However, we argue models despite capturing these properties deviate from their expected routing performance. We use realistic traces to validate this observation on two mobility models. Our empirical results for epidemic routing show those models' largely differ (delay 67% & reachability 79%) from the observed values. This in-turn call for two ...

2010-01-01

317

A Direct Precision Measurement of the Intergalactic Lyman-alpha Opacity at 2  

CERN Document Server

We directly measure the evolution of the intergalactic Lyman-alpha effective optical depth, tau_eff, over the redshift range 2 is <1% at z=2, 4% at z=3, and 12% at z=4. Previous measurements of tau_eff at 3statistical metal removal results in the literature, finding that this contribution is ~6-9% at z=3 and decreases monotonically with redshift. The high precision of our measurement, attaining 3% in redshift bins of width Delta z=0.2 aro und z=3, indicates significant departures from the best-fit power-law redshift evolution (tau_eff=0.0018(1+z)^3.92, when metals are left in), particularly near z=3.2. The observed downward departure is statistically consistent with a ...

2007-01-01

318

The thermodynamic characteristics of retention of tricyclo[5.2.1.02,6]decane isomer molecules on different sorbents in gas chromatography  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of sorption of the isomeric tricyclo[5.2.1.02.6]decane (tetrahydrodicyclopentadiene, TDCPD) molecules were for the first time determined experimentally and by molecular statistical methods under the conditions of gas-adsorption chromatography on graphitized thermal carbon black and gas-liquid chromatography on stationary liquid phases of different polarities (Apiezon L and Carbowax 20M). The effects of the chemical nature of sorbents on the retention of the TDCPD isomers are considered. A procedure for calculating the thermodynamic characteristics of adsorption of molecules with a complex structure is suggested within the framework of the atom-atom approximation of the semiempirical molecular statistical theory of adsorption for the example of isostructura...

2008-01-01

319

The null hypothesis: closing the gap between good intentions and good studies  

British Library Electronic Table of Contents (United Kingdom)

Some papers appearing in the two leading clinical journals of our specialty have fundamental defects in design, statistical analysis, and reporting. Actual publications are used to illustrate what investigators should and should not do, from initial planning through to their finished manuscript. A more detailed discussion of the most common statistical methods used in reproductive research is given as an online supplement. Some of these deficiencies illustrate the importance of registry of all study parameters for randomized clinical trials, a process covered in greater detail in an accompanying review and required for those manuscripts to be considered. Authors and reviewers need to be more aware of these requirements and common errors and pitfalls so that only quality manuscripts are pub...

2011-01-01

320

Statistical design of experiments as a tool for optimizing the batch conditions to methylene blue biosorption on yellow passion fruit and mandarin peels  

British Library Electronic Table of Contents (United Kingdom)

In order to reduce the total number of experiments for achieving the highest removal of methylene blue (MB) from aqueous solutions using yellow passion fruit peel (Passiflora edullis, F. flavicarpa) and mandarin peel (Citrus reticulata) as biosorbents two independent sets of full 23 factorial designs with two central points (10 experiments) were experimented. In order to continue the optimization of the system a new full 22 factorial design with two central points (six experiments) and a central composite surface analysis (13 experiments, divided into four cube points, five centre points, and four axial points) were employed for yellow passion fruit peel (PFP) and mandarin peel (MP), respectively. Using these statistical tools, the best conditions for MB removal from aqueous solution were ...

2007-01-01

321

Sex determination using discriminant function analysis in children and adolescents: a lateral cephalometric study  

British Library Electronic Table of Contents (United Kingdom)

The objective of this study is to test the validity of sex determination in children and adolescents using lateral radiographic cephalometry and discriminant function analysis. Fifty male and 50 female cephalograms of Taiwanese children were used (males and females with mean age of 15.52???1.38 and 15.67???1.54?years, respectively). Twenty-two cephalometric measurements were performed using computerized cephalometry. Statistical analysis shows that all measurements were sexually dimorphic (p?statistically validated and clinically relevant, were used for discriminant function analysis. A stepwise discriminant procedure selected seven of the nine variables, producing 95% accuracy in sex determination. Resubstitution classification reveals the same discriminant rat...

2010-01-01

322

Schooling for All in South Africa: Closing the Gap  

Science.gov (United States)

It has been widely assumed that South Africa has achieved universal basic education. Through an analysis of the 2001 census and two national enrolment datasets rather than statistical projections, this study re-examines this assumption and provides new estimates of enrolment levels in primary, basic and secondary education. Using GER, NER, and ASER indicators, disaggregated by gender and province, the study shows that access to education in South Africa is not as widespread as published sources note. While statistics show that national access levels are lower than prevailing estimates, the relatively high levels of access in some of the most disadvantaged provinces suggest the need to re-evaluate assumptions about targets for universal access for developing regions. In addition, the analysis reveals South Africa's unexpected and provocative gendered patterns of access and participation.

2007-03-01

323

Return on Investment: Libraries and Student Retention  

British Library Electronic Table of Contents (United Kingdom)

Using data on libraries collected by the Association of Research Libraries (ARL) and the Association of College and Research Libraries (ACRL), as well as fall-to-fall retention rates obtained from the Integrated Postsecondary Education Data System (IPEDS) of the National Center for Education Statistics (NCES), this study employs statistical measures of association to analyze the relationship of both library expenditures and number of professional library staff to student persistence. The strongest relationships found were those between student retention and total library expenditures, total library materials costs, and serial costs for institutions categorized as baccalaureate colleges within the Carnegie Classification System. The most significant relationship between persistence and numb...

2007-01-01

324

Reporting bias when using real data sets to analyze classification performance  

British Library Electronic Table of Contents (United Kingdom)

Motivation: It is commonplace for authors to propose a new classification rule, either the operator construction part or feature selection, and demonstrate its performance on real data sets, which often come from high-dimensional studies, such as from gene-expression microarrays, with small samples. Owing to the variability in feature selection and error estimation, individual reported performances are highly imprecise. Hence, if only the best test results are reported, then these will be biased relative to the overall performance of the proposed procedure. Results: This article characterizes reporting bias with several statistics and computes these statistics in a large simulation study using both modeled and real data. The results appear as curves giving the different reporting biases as...

2010-01-01

325

Predicting the proton conductivity of perfluorosulfonic acid membrane via combining statistical thermodynamics and molecular dynamics simulation  

British Library Electronic Table of Contents (United Kingdom)

Abstract The electrochemical properties of a perfluorosulfonic acid (PFSA) membrane are estimated using a combination of molecular dynamics simulation and statistical thermodynamic model. We obtain all parameters in an ionic conductivity model from an atomistic simulation and remove all adjusted model parameters. From a microscopic point of view, the hydrated PFSA membrane shows micro-phase segregation which separated into hydrophilic and hydrophobic phases. Our present work originates with this phenomenon and we treat this phase segregation as if it is a continuous phase for each of which the proton (H+) is transported inside the PFSA membrane/solvent (water and alcohols) mixture. The chemical potential for a given system is estimated using a molecular simulation technique to predict the ...

2011-01-01

326

Plain radiographic predictors of survival in treated Ewing's sarcoma  

International Nuclear Information System (INIS)

We analyzed 16 radiographic features of primary Ewing's sarcoma in 342 patients from the IESS 7299 (Intergroup Ewing's Sarcoma Study) for prognostic significance. Of these, 3 features demonstrated a statistically significant relationship to survival: maximal tumor dimension, tumor location, and an appearance of honeycombing within the lesion. Those individuals with primary lesions centered in the pelvis, femur, or humerus had a worse survival rate than those with lesions centered elsewhere. Similarly, we observed an inverse relationship between the greatest dimension of the osseous portion of the lesion and survival. The radiographic finding of honeycombing also showed a statistical association with improved survival. However, this feature was observed infrequently, and its significance should be assessed further. Otherwise, no other feature that we analyzed showed any relationship to patient prognosis. (orig.).

327

Online monitoring of steel casting processes using multivariate statistical technologies: From continuous to transitional operations  

British Library Electronic Table of Contents (United Kingdom)

This paper describes a state-of-the-art online monitoring system using multivariate statistical technologies for continuous steel casting process, which was commissioned at Dofasco's No. 2 caster to provide consistent indication of process health for caster's start-up, continuous production and transitional operations. The paper particularly focuses on development of a novel scheme to synchronize process trajectories for monitoring specific transitional operations such as equipment or steel product grade changes. The proposed scheme is demonstrated by several industrial examples with the results showing good detectability of various process abnormalities. With the aid of this fully integrated, innovative monitoring system, Dofasco has generated significant value through improved productivi...

2006-01-01

328

New Permeameters for In Situ Characterization of Unsaturated Heterogeneous Permeability: Development, Design, Testing, and Application  

Energy Technology Data Exchange (ETDEWEB)

The original objective of our EMSP research was to design, develop, and test new in situ field permeameters for use in spatial variability studies of unsaturated hydraulic properties. We initially focused on activities related to development and testing of techniques for inverting permeameter data, development of numerical tools for data inversion, error evaluation for permeameter design, and permeameter component design. However, the results of error evaluations for permeameter design caused us to redirect our research, and reformulate our research objectives. We discovered that small, simple measurement errors lead to significant bias in the estimated hydraulic properties and their spatial statistics. Our reformulated research objective became the evaluation of the origin, impact and relevance of spatial bias in field-and laboratory-estimated unsaturate hydraulic properties, with an emphasis on spatial statistics and the resulting predictions ...

2001-12-01

329

Monte Carlo characterization of an ytterbium-169 high dose rate brachytherapy source with analysis of statistical uncertainty  

International Nuclear Information System (INIS)

An ytterbium-169 high dose rate brachytherapy source, distinguished by an intensity-weighted average photon energy of 92.7 keV and a 32.015#+-#0.009 day half-life, is characterized in terms of the updated AAPM Task Group Report No. 43 specifications using the MCNP5 Monte Carlo computer code. In accordance with these specifications, the investigation included Monte Carlo simulations both in water and air with the in-air photon spectrum filtered to remove low-energy photons below 10 keV. TG-43 dosimetric data including S_K, D(r,#theta#), #LAMBDA#, g_L(r), F(r,#theta#), #phi#_a_n(r), and #phi#_a_n were calculated and statistical uncertainties in these parameters were derived and calculated in the appendix.

2006-01-01

330

Monitoring urban land cover and vegetation change by multi-temporal remote sensing information  

British Library Electronic Table of Contents (United Kingdom)

In order to analyze changes in human settlement in Xuzhou city during the past 20 years, changes in land cover and vegetation were investigated based on multi-temporal remote sensing Landsat TM images. We developed a hierarchical classifier system that uses different feature inputs for specific classes and conducted a classification post-processing approach to improve its accuracy. From our statistical analysis of changes in urban land cover from 1987 to 2007, we conclude that built-up land areas have obviously increased, while farmland has seen in a continuous loss due to urban growth and human activities. A NDVI difference approach was used to extract information on changes in vegetation. A false change information elimination approach was developed based on prior knowledge and statistic...

2010-01-01

331

Molecular statistical calculation of thermodynamic characteristics of adsorption of O-, S-, and Se-containing heteroadamantanes on graphitized thermal carbon black  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption (TCA) on the basal face of graphite have been calculated in terms of the semiempirical molecular statistical theory of adsorption for molecules of O-, S-, and Se-containing heteroadamantanes of different structure and isostructural cyclohexane derivatives. The influence of the nature, number, and position of heteroatoms in the adamantane framework on the TCA values was studied in detail, which made it possible to predict the retention of the compounds considered on the surface of graphitized thermal carbon black under the conditions of equilibrium gas adsorption chromatography. The introduction of each subsequent heteroatom into a polyheteroadamantane molecule makes a non-additive contribution to the TCA values. The contributions of various f...

2010-01-01

332

Modeling protein synthesis from a physicist's perspective: a toy model  

CERN Document Server

Proteins are polymers of amino acids. These macromolecules are synthesized by intracellular machines called {\\it ribosome}. Although, traditionally, the experimental investigation of protein synthesis has been an active area of research in molecular cell biology, important quantitative models of this phenomenon have been reported mostly in the research journals devoted to statistical physics and related interdisciplinary topics. From the perspective of a physicist, protein synthesis is a phenomenon of {\\it classical transport of interacting ribosomes on a messenger RNA (mRNA) template} that dictates the sequence of the amino acids on the protein. Here we bring this frontier area of contemporary research into the classroom by appropriate simplification of the models and methods. In particular, we develope a simple toy model and analyze it by some elementary techniques of non-equilibrium statistical mechanics to predict the average rate of ...

2007-01-01

333

Kinesiological surface electromyography in normal children: Range of normal activity and pattern analysis  

British Library Electronic Table of Contents (United Kingdom)

To document the range of activity and patterns of normal surface kinesiological electromyography in normal children, 87 children ranging from age 3 to 18 years who were developing normally were evaluated at free walking speed. Analysis was performed on 6307 gait cycles from 11 different muscles with custom software. We devised an algorithm to do a computer-based KEMG curve pattern analysis to sort out curves that did not match the physiologic muscle activity pattern, We also devised a combined preset amplitude and statistics-based criteria to satisfactorily determine the onset/cessation of KEMG activity. The measurements of timing and duration of activity, body height and weight, body mass index, cadence, stride length, and age were obtained for statistical analysis. From the pattern recog...

2007-01-01

334

Extraction methods of phase information for X-ray diffraction enhanced imaging  

Energy Technology Data Exchange (ETDEWEB)

X-ray diffraction enhanced imaging (DEI) is one of X-ray phase-contrast imaging methods, which is applied to inspect internal structures of weakly absorbing low-Z samples. The key problem of the DEI is how to extract phase information which is expressed by refraction-angle images from a series of DEI images measured in different positions of the rocking curve of the analyzer. Three effective extraction methods are presented in this paper: the statistical geometric-optics-approximation method, the maximum refraction-angle method and the Gaussian curve fitting method. They are compared with the existing methods, such as the D. Chapman's geometric optics approximation method and the multiple-images statistical method. A 2D computer simulation experiment is performed to draw comparisons of these methods. The experimental results prove that the above three methods have more precision of refraction-angle values than existing methods.

2007-08-21

335

Extraction methods of phase information for X-ray diffraction enhanced imaging  

International Nuclear Information System (INIS)

X-ray diffraction enhanced imaging (DEI) is one of X-ray phase-contrast imaging methods, which is applied to inspect internal structures of weakly absorbing low-Z samples. The key problem of the DEI is how to extract phase information which is expressed by refraction-angle images from a series of DEI images measured in different positions of the rocking curve of the analyzer. Three effective extraction methods are presented in this paper: the statistical geometric-optics-approximation method, the maximum refraction-angle method and the Gaussian curve fitting method. They are compared with the existing methods, such as the D. Chapman's geometric optics approximation method and the multiple-images statistical method. A 2D computer simulation experiment is performed to draw comparisons of these methods. The experimental results prove that the above three methods have more precision of refraction-angle values than existing methods.

2007-08-21

336

Experimental investigation of wall static pressure fluctuations in parallel boiling flow  

International Nuclear Information System (INIS)

Measurements of the statistical characteristics of channel wall static pressure fluctuations in parallel one-component boiling flow are reported. The measurements span a wide range of local subcooling and vapor volume fraction, and correspond to flow regimes ranging from highly subcooled bubbly to saturated slug-annular. Vapor volume fraction measurements at the pressure measurement station are also reported in conjunction with visual observation of the flow structure. Variation of static pressure fluctuation intensity and spectral content with local thermal-hydraulic condition is demonstrated. Finally, it is suggested that diagnosis of local two-phase flow regime on the basis of (i) statistical characteristics of the pressure data, and (ii) time trace of pressure signal, may be possible. 15 refs.

1980-01-01

337

Electric power monthly, June 1995 with data for March 1995  

Energy Technology Data Exchange (ETDEWEB)

The Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy prepares the EPM. This publication provides monthly statistics at the State, Census division, and US levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source; consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant. 68 tabs.

1995-06-19

338

Electric power monthly with data for October 1995  

Energy Technology Data Exchange (ETDEWEB)

The Coal and Electric Data and Renewables Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy prepares the EPM. This publication provides monthly statistics at the State, Census division, and U.S. levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source; consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant.

1996-01-01

339

Electric power monthly  

Energy Technology Data Exchange (ETDEWEB)

The Electric Power Monthly is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the national, Census division, and State levels for net generation, fuel consumption, fuel stocks, quantity and quality of fuel, cost of fuel, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fuel are also displayed for the North American Electric Reliability Council (NERC) regions. Additionally, statistics by company and plant are published in the EPM on capability of new plants, new generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fuel.

1992-05-01

340

Econophysics review: II. Agent-based models  

British Library Electronic Table of Contents (United Kingdom)

This article is the second part of a review of recent empirical and theoretical developments usually grouped under the heading Econophysics. In the first part, we reviewed the statistical properties of financial time series, the statistics exhibited in order books and discussed some studies of correlations of asset prices and returns. This second part deals with models in Econophysics from the point of view of agent-based modeling. Of the large number of multi-agent-based models, we have identified three representative areas. First, using previous work originally presented in the fields of behavioral finance and market microstructure theory, econophysicists have developed agent-based models of order-driven markets that we discuss extensively here. Second, kinetic theory models designed to ...

2011-01-01

341

Direct injection of natural gas in blast furnaces at high rates: Preliminary statistical analysis of blast furnace carbon balance at Armco-Middletown. Topical report, January 1990-September 1992  

Science.gov (United States)

The economic benefits of supplemental fuel injections depend, in part, on the coke replacement ratio. An assessment of the accuracy with which blast furnace coke rate may be measured and a determination of the key drivers of coke rate uncertainty are offered, to provide guidance for experiments in high-rate gas injection. Using statistical analysis tools, an expression for the measurement error associated with the various terms of blast furnace carbon balance is developed. Coke rate calculations based on the material balance are most sensitive to coke carbon content and to proper tracking of hot metal tapping schedule.

1992-09-01

342

Covariances for neutron cross sections calculated using a regional model based on local-model fits to experimental data  

Energy Technology Data Exchange (ETDEWEB)

We suggest a procedure for estimating uncertainties in neutron cross sections calculated with a nuclear model descriptive of a specific mass region. It applies standard error propagation techniques, using a model-parameter covariance matrix. Generally, available codes do not generate covariance information in conjunction with their fitting algorithms. Therefore, we resort to estimating a relative covariance matrix a posteriori from a statistical examination of the scatter of elemental parameter values about the regional representation. We numerically demonstrate our method by considering an optical-statistical model analysis of a body of total and elastic scattering data for the light fission-fragment mass region. In this example, strong uncertainty correlations emerge and they conspire to reduce estimated errors to some 50% of those obtained from a naive uncorrelated summation in quadrature. 37 references.

1983-11-01

343

Correlation, hierarchies, and networks in financial markets  

CERN Document Server

We discuss some methods to quantitatively investigate the properties of correlation matrices. Correlation matrices play an important role in portfolio optimization and in several other quantitative descriptions of asset price dynamics in financial markets. Specifically, we discuss how to define and obtain hierarchical trees, correlation based trees and networks from a correlation matrix. The hierarchical clustering and other procedures performed on the correlation matrix to detect statistically reliable aspects of the correlation matrix are seen as filtering procedures of the correlation matrix. We also discuss a method to associate a hierarchically nested factor model to a hierarchical tree obtained from a correlation matrix. The information retained in filtering procedures and its stability with respect to statistical fluctuations is quantified by using the Kullback-Leibler distance.

2008-01-01

344

Communication and Round Efficient Information Checking Protocol  

CERN Document Server

In this paper, we present a very important primitive called Information Checking Protocol (ICP) which plays an important role in constructing statistical Verifiable Secret Sharing (VSS) and Weak Secret Sharing (WSS) protocols. Informally, ICP is a tool for authenticating messages in the presence of computationally unbounded corrupted parties. Here we extend the basic bare-bone definition of ICP, introduced by Rabin et al. and then present an ICP that attains the best communication complexity and round complexity among all the existing ICPs in the literature. We also show that our ICP satisfies several interesting properties such as linearity property which is an important requirement in many applications of ICP. Though not presented in this paper, we can design communication and round efficient statistical (i.e involves negligible error probability in computation) VSS and Multiparty Computation (MPC) protocol using our new ICP.

2010-01-01

345

An experimental and molecular-statistical study of the adsorption of the iodobenzene, 2-iodothiophene, and isomeric iodoadamantane molecules on the graphite basal face surface  

Science.gov (United States)

The thermodynamic characteristics of adsorption of iodobenzene, 2-iodothiophene, and 1- and 2-iodoadamantanes on the surface of graphitized thermal carbon black were determined experimentally. The influence of the special features of the molecular structure of the adsorbates on the thermodynamic characteristics of adsorption was studied. The atom-atom approximation of the semiempirical molecular-statistical theory of adsorption was used to calculate the thermodynamic characteristics of adsorption of the adsorbates using the newly determined potential function parameters of pair intermolecular interaction (?( r)) of I with C atoms of the basal graphite face. For the example of isostructural monohalogenated benzenes, thiophenes, and adamantanes, a comparative analysis of the contributions of the F, Cl, Br, and I atoms to the thermodynamic characteristics of adsorption was performed for the nonspecific adsorption of these compounds on a plane graphitized carbon black ...

2011-04-01

346

A specification test for univariate and multivariate proportional hazards models.  

Science.gov (United States)

This paper applies White's (1982, Econometrica 50, 1-25) information matrix (IM) test for correct model specification to proportional hazards models of univariate and multivariate censored survival data. Several alternative estimators of the test statistic are presented and their size performance examined. White also suggested an estimator of the parameter covariance matrix that was robust to certain forms of model misspecification. This has been subsequently proposed by others (e.g., Royall, 1986, International Statistical Review 54, 221-226) and applied by Huster, Brookmeyer, and Self (1989, Biometrics 45, 145-156) as part of an independence working model (IWM) approach to multivariate censored survival data. We illustrate how the IM test can be used for both univariate data and as part of the IWM approach to multivariate data. PMID:8117901

1993-12-01

347

A refined lack-of-fit statistic to calibrate pesticide fate models for responsive systems  

British Library Electronic Table of Contents (United Kingdom)

BACKGROUND: Calibration by inverse modelling was performed with the MACRO transport and fate model using long-term (>10 years) drainflow and isoproturon (IPU) data from western France. Two lack-of-fit (LOF) indices were used to control the inverse modelling: sum of squares (SS) and an alternative statistic called the vertical-horizontal distance integrator (VHDI), which is designed to account for offsets in observed and predicted arrival times of peak IPU concentration. With these data, SS was artificially inflated because it is limited to comparison of predicted and observed IPU concentrations that are concurrent in time. The LOFs were used along with the index of agreement (d) and the correlation coefficient (r) to ascertain the fit of the calibrated models. RESULTS: Predicted arrival ti...

2009-01-01

348

A gradient-based algorithm for semiparametric models with missing covariates  

British Library Electronic Table of Contents (United Kingdom)

In the parametric regression model, the covariate missing problem under missing at random is considered. It is often desirable to use flexible parametric or semiparametric models for the covariate distribution, which can reduce a potential misspecification problem. Recently, a completely nonparametric approach was developed by [H.Y. Chen, Nonparametric and semiparametric models for missing covariates in parameter regression, J. Amer. Statist. Assoc. 99 (2004), pp. 1176-1189; Z. Zhang and H.E. Rockette, On maximum likelihood estimation in parametric regression with missing covariates, J. Statist. Plann. Inference 47 (2005), pp. 206-223]. Although it does not require a model for the covariate distribution or the missing data mechanism, the proposed method assumes that the covariate distribut...

2011-01-01

349

A commercial microbial enhanced oil recovery process: statistical evaluation of a multi-project database  

Energy Technology Data Exchange (ETDEWEB)

This paper discusses a database of information collected and organized during the past eight years from 2,000 producing oil wells in the United States, all of which have been treated with special applications techniques developed to improve the effectiveness of MEOR technology. The database, believed to be the first of its kind, has been generated for the purpose of statistically evaluating the effectiveness and economics of the MEOR process in a wide variety of oil reservoir environments, and is a tool that can be used to improve the predictability of treatment response. The information in the database has also been evaluated to determine which, if any, reservoir characteristics are dominant factors in determining the applicability of MEOR.

1995-12-31

350

The study of dual energy X-ray absorptiometry on body composition components in obesity  

International Nuclear Information System (INIS)

Objective: To study the correlation of the bone mineral density (BMD) and the body composition components of body mass index (BMI), FAT and LEAN in Chinese obesity. Methods: There were 150 cases in obesity group diagnosed by BMI, including 75 males [ median age 46 years, mean weight (89.64 #+-# 8.33) kg] and 75 females [median age 45 years, mean weight (77.23 #+-# 6.85) kg]. There were 150 persons with normal BMI in the control group, including 75 males [(median age 47 years, mean weight (62.34 #+-# 5.72) kg] and 75 females [ median age 45 years, mean weight (50.16 #+-# 5.06) kg]. The body height and weight of 300 persons in two groups were measured respectively and ,simultaneously calculated the BMI. These data and the body composition parameters measured by the dual energy X-ray absorptiometry (DEXA) in these two groups were compared and analyzed. The data obtained used two-sample t-test analysis, bi-variable correlation used Pearson linear correlation analysis ...

2009-06-01

351

Experimental Electron Heat Diffusion in TJ-II ECRH Plasmas  

Energy Technology Data Exchange (ETDEWEB)

Interpretative transport has been used to revisit the global scalings of TJ-II ECRH plasmas from a local perspective. Density, rotational transform and ERCH power scans were analysed based upon Thomson Scattering data (electron density and temperature) in steady state discharges. A simple formula to obtain the thermal conductivity, assuming pure diffusion and negligible convective heat fluxes was used in a set of 161 discharges. All the analysis was performed with the ASTRA transport shell. The density scan indicates that inside n=0,4 there is no significant change of e with density in the range studied (0.4 <ne>(1019m-3) 1.0), while in 0,5 <0,8 approximately, e decreases with density. In the rotational transform scan it is found that the values of e when a low order rational of the rotational transform is present locally seem to be smaller for the corresponding ...

2006-07-01

352

Adsorption of argon from sub- to supercritical conditions on graphitized thermal carbon black and in graphitic slit pores: A grand canonical Monte Carlo simulation study  

Science.gov (United States)

In this paper we consider the adsorption of argon on the surface of graphitized thermal carbon black and in slit pores at temperatures ranging from subcritical to supercritical conditions by the method of grand canonical Monte Carlo simulation. Attention is paid to the variation of the adsorbed density when the temperature crosses the critical point. The behavior of the adsorbed density versus pressure (bulk density) shows interesting behavior at temperatures in the vicinity of and those above the critical point and also at extremely high pressures. Isotherms at temperatures greater than the critical temperature exhibit a clear maximum, and near the critical temperature this maximum is a very sharp spike. Under the supercritical conditions and very high pressure the excess of adsorbed density decreases towards zero value for a graphite surface, while for slit pores negative excess ...

2005-08-01

353

Zero-motion flucton correlations in high-energy proton elastic scattering on /sup 40/C  

Energy Technology Data Exchange (ETDEWEB)

The 1.04 GeV-proton elastic scattering from /sup 40/Ca is studied in the framework of the coherent density fluctuation model (CDFM). The calculations are carried out in the Glauber theoretical scheme with three different charge densities. It is shown that: i) the account of the flucton correlations leads to results considerably different from those obtained in the independent particle Glauber approach (IPGA); ii) in contrast to the case of IPGA the use of a more realistic density improves the agreement of CDPM-results with the experimental data.

1985-03-01

354

Zero-motion flucton correlations in high-energy proton elastic scattering on "4"0C  

International Nuclear Information System (INIS)

The 1.04 GeV-proton elastic scattering from "4"0Ca is studied in the framework of the coherent density fluctuation model (CDFM). The calculations are carried out in the Glauber theoretical scheme with three different charge densities. It is shown that: i) the account of the flucton correlations leads to results considerably different from those obtained in the independent particle Glauber approach (IPGA); ii) in contrast to the case of IPGA the use of a more realistic density improves the agreement of CDPM-results with the experimental data. (orig.).

355

Temperature dependence of molar excess volumes for the dimethyl sulfoxide + thiophene system and thermal expansion coefficients between 293. 15 and 313. 15 K  

Energy Technology Data Exchange (ETDEWEB)

Densities were measured with a vibrating-tube densimeter for binary mixtures of dimethyl sulfoxide + thiophene at temperatures from 293.15 to 313.15 K as a function of composition. Molar excess volumes V[sup E] for the mixtures, determined from the density data, are negative and become more negative with an increase in temperature. The coefficients of thermal expansion were also evaluated from the temperature dependence of the density.

1993-04-01

356

Reflection of electromagnetic waves by a nonuniform plasma layer covering a metal surface  

International Nuclear Information System (INIS)

Reflection coefficients of electromagnetic waves in a nonuniform plasma layer with electrons, positive ions and negative ions, covering a metal surface are investigated by using the finite-difference-time-domain method. It is shown that the reflection coefficients are influenced greatly by the density gradient on the layer edge, layer thickness and electron proportion, i.e., the effect of the negative ions. It is also found that low reflection or high attenuation can be reached by properly choosing high electron proportion, thick plasma layer, and smooth density gradient in the low frequency regime, but sharp density gradient in the high frequency regime. (authors)

2008-07-01

357

Quantitative density measurements from a real-time neutron radiography system  

Energy Technology Data Exchange (ETDEWEB)

An advanced video system has been assembled from commercially available equipment to support the real-time neutron radiography facility established jointly by the University of Virginia Department of Nuclear Engineering and Engineering Physics, and the Philip Morris Research Center. A schematic diagram of the equipment used for real-time neutron radiography is presented. To obtain quantitative density measurements with this system, several modifications of both hardware and image processing software were required. After implementation of these changes, the system was capable of determining material densities by measuring the degree of neutron attenuation.

1986-01-01

358

Quantitative density measurements from a real-time neutron radiography system  

International Nuclear Information System (INIS)

An advanced video system has been assembled from commercially available equipment to support the real-time neutron radiography facility established jointly by the University of Virginia Department of Nuclear Engineering and Engineering Physics, and the Philip Morris Research Center. A schematic diagram of the equipment used for real-time neutron radiography is presented. To obtain quantitative density measurements with this system, several modifications of both hardware and image processing software were required. After implementation of these changes, the system was capable of determining material densities by measuring the degree of neutron attenuation.

1986-11-16

359

Noise spectral density measurements of a radiation hardened CMOS process in the weak and moderate inversion  

Energy Technology Data Exchange (ETDEWEB)

The authors have measured the noise of MOS transistors of the United Technology Microelectronics Center (UTMC) 1.2 [mu]m radiation hardened CMOS P-well process from the weak to moderate inversion region. The noise power spectral densities of both NMOS and PMOS devices were measured from 1 KHz to 50 MHz. The bandwidth was chosen such that the important components of the spectral densities such as the white thermal noise and the 1/f noise could be easily resolved and analyzed in detail. In this paper the effects of different device terminal DC biases and channel geometries on the noise are described.

1992-08-01

360

Measurement of Turbulence Decorrelation during Transport Barrier Evolution in a High Temperature Fusion Plasma  

Energy Technology Data Exchange (ETDEWEB)

A low power polychromatic beam of microwaves is used to diagnose the behavior of turbulent fluctuations in the core of the JT-60U tokamak during the evolution of the internal transport barrier. A continuous reduction in the size of turbulent structures is observed concomitant with the reduction of the density scale length during the evolution of the internal transport barrier. The density correlation length decreases to the order of the ion gyroradius, in contrast to the much longer scale lengths observed earlier in the discharge, while the density fluctuation level remain similar to the level before transport barrier formation.

2005-03-29

361

Local-density-functional approximation to the energy band structure of TmS using the self-consistent relativistic linearized-augmented-plane-wave method  

International Nuclear Information System (INIS)

The self-consistent relativistic linearized-augmented-plane-wave method is applied to local-density calculation of electronic structure of TmS. It is found that thulium monosulphide is a compound with a trivalent state of thulium. The influence of spin-orbital interaction is shown for different symmetry states of electrons. Calculated densities of states are used for the estimation of the electron-phonon coupling constant. And in conclusion it is shown that TmS is a high temperature Kondo-like system. (author).

362

Level density parameter and fission probability calculations in heavy-ion-induced fission reactions  

International Nuclear Information System (INIS)

Based on the single-particle levels given by Nilsson, the intrinsic and effective (with collective effects) level density parameters as a function of the excitation energy for the "1"8"6Os, "1'8"7Ir, "1"8"9Os and "1"9"3Au deformation nuclei have been calculated in the range of the excitation energy up to 150 MeV. The calculated fission probabilities P_f (U) are consistent satisfactorily with the experimental data when a nonadiabatic estimation of the collective effects was used to calculated the nuclear level density parameters.

363

Interferometry and refraction measurements in plasmas of elliptical cross-section  

Energy Technology Data Exchange (ETDEWEB)

The measurement of electron densities using interferometry and refraction measurements in plasmas with cross-sections where the electron density contours are concentric ellipses is examined. Transforms are found for both interferometrically deduced optical path-length differences and refraction angle data obtained from elliptical cross-section plasmas. The transformed data can be inverted to give electron densities using standard techniques developed for circular cross-section plasmas. Refraction of light in elliptical cross-section plasmas is examined using numerical ray tracing.

1984-04-14

364

Direct laser initiation of PETN  

Energy Technology Data Exchange (ETDEWEB)

In the early 1970s Yang and Menichelli demonstrated that direct laser illumination of low-density secondary explosive prr:ssings through a transparent window could produce detonation. 'The energy requirement for threshold initiation of detonation was reduced when a thin metal coating of metal covered the side of the window against which the low-density explosive was pressed. We have obtained experimental results that are in general agreement with the results of Renllund, Stanton and Trott (1 989) and recent: work by Nagayama, hou and Nakahara (2001). We report exploration of the effects of laser beam diameter, PEiTN density and specific surface area, and thickness of a titanium coating on the window.

2001-01-01

365

Changes of the electron density distribution during MHD activity in CHS  

Energy Technology Data Exchange (ETDEWEB)

Density oscillations induced by MHD activities were observed in NBI heated plasmas on CHS by using an HCN laser interferometer. The accompanied changes of the density profiles were also observed. The oscillations are composition of m=0 sawteeth like crash and m=2 sinusoidal oscillations as a post courser of the crash. Possible models of the oscillation structure are examined in order to explain experimental data of the interferometer. Rotating plasma core, which is hollow profile and keeps constant elongation of the flux surface can explain amplitude and phase distribution of the sinusoidal oscillation. (author)

2000-09-01

366

Application of a 3-beam #gamma# densitometer to two-phase flow regime and density measurements  

International Nuclear Information System (INIS)

A method of using gamma radiation to determine the density and phase distribution in two-phase flows in pipes is described. Three collimated beams of radiation that pass through a pipe cross-section at different radial positions are used. A theory and computer program used to relate the measured attenuation of these beams to a three-parameter model of the phase distribution and to the average density and void fraction are discussed. Data obtained during both static and dynamic verification experiments using Lucite inserts are presented, as well as the results of several tests done in high pressure, steam-water flows.

1976-08-11

367

Anisotropic mass density by two-dimensional acoustic metamaterials  

Energy Technology Data Exchange (ETDEWEB)

We show that specially designed two-dimensional arrangements of full elastic cylinders embedded in a nonviscous fluid or gas define (in the homogenization limit) a new class of acoustic metamaterials characterized by a dynamical effective mass density that is anisotropic. Here, analytic expressions for the dynamical mass density and the effective sound velocity tensors are derived in the long wavelength limit. Both show an explicit dependence on the lattice filling fraction, the elastic properties of cylinders relative to the background, their positions in the unit cell, and their multiple scattering interactions. Several examples of these metamaterials are reported and discussed.

2008-02-15

368

WALL PRESSURE FLUCTUATIONS UNDER TURBULENT ...  

Science.gov (United States)

... necessary to allow for the effata nr the finits size of the oressure tranaducer on both the root mean square and power spectral density measurements ...

1963-04-01

369

Virial estimator for dark energy  

CERN Document Server

A new estimator of the local density of dark energy is suggested which comes from the virial theorem for non-relativistic gravitating systems embedded in the uniform dark energy background.

2011-01-01

370

Vibratory Dynamics of Flow-Excited Struts in Water  

Science.gov (United States)

... The lateral cross spectral density measurements are normalized on the autospectrum. Frequency is normalized on r3 , and we take Uc _" 0.7 U0 . ...

1973-12-01

371

Variational method for estimating the rate of convergence of Markov Chain Monte Carlo algorithms  

CERN Document Server

We demonstrate the use of a variational method to determine a quantitative lower bound on the rate of convergence of Markov Chain Monte Carlo (MCMC) algorithms as a function of the target density and proposal density. The bound relies on approximating the second largest eigenvalue in the spectrum of the MCMC operator using a variational principle and the approach is applicable to problems with continuous state spaces. We apply the method to one dimensional examples with Gaussian and quartic target densities, and we contrast the performance of the basic Metropolis-Hastings algorithms with a ``smart'' variant that incorporates gradient information into the trial moves. We find that the variational method agrees quite closely with numerical simulations. We also see that the smart MCMC algorithm often fails to converge geometrically in the tails of the target density except in the simplest case we examine, ...

2006-01-01

372

United States Air Force Summer Research Program 1991. ...  

Science.gov (United States)

... 14. Pfeifer, HJ, (1986), "Correlation and Spectral Density Measurements by LDA," Proceedings of the 5th International Congress on Applications of ...

1992-01-09

373

Time Characterization of High Density Gas Jet from a Pulsed Supersonic Nozzle via Laser Produced Plasma  

International Nuclear Information System (INIS)

A high-density gas jet supersonic nozzle is reported in this paper. The jitter and actuation time of the nozzle is determined by the pin discharge and laser spark radiation respectively. The jitter time of the nozzle is within 10 ?s with the backing pressure as high as 25 bar. With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle, the actuation time is calculated to be about 15 ms by detecting the laser produced spark radiation, which reveals the existence of the gas jet and the relative gas density evolving with time. Consequently the gas density is estimated to be well above 1019 cm-3, compared with theoretical simulations from the nozzle parameters.

2006-07-01

374

Thermal Performance of Low Layer Density Multilayer Insu1ation Using Liquid Nitrogen  

Science.gov (United States)

In order to support long duration cryogenic propellant storage, the Cryogenic Fluid Management (CFM)

2011-01-01

375
376

The Influence of Inert Particulate Material on the Properties of ...  

Science.gov (United States)

... Briefly, a standard detonator (normally the Scale 1 Gap Test Donor, comprising an exploding bridgewire to initiate a low density PETN pellet and ...

1984-05-01

377

The Assessment of Fracture Risk  

UK PubMed Central (United Kingdom)

Bone mineral density is considered to be the standard measure for the diagnosis of osteoporosis and the assessment of fracture risk. The majority of fragility fractures occur in patients with bone mineral...Full Text Available

2010-03-01

378

Structural Response of Marine Sandwich Panels to Uniform ...  

Science.gov (United States)

... Composite sandwich panels with fiber reinforced plastic (FRP) faces and low 3 density foam cores are fast becoming the structural material of ...

1990-06-01

379

Strain-dependent variation in collateral circulatory function in mouse hindlimb  

UK PubMed Central (United Kingdom)

The extent (density and diameter) of the native (preexisting) collateral circulation in healthy tissues and the capacity of collaterals to enlarge/remodel in obstructive arterial disease are important...Full Text Available

2010-08-01

380

Stability of space-charge neutralized beams  

Science.gov (United States)

Consideration is given to the stability of negative ion beams which are neutralized through ionization of a background gas. Two types of instabilities are examined. First, beam-plasma instabilities are analyzed with the dispersion relation showing that they are unimportant if the beam velocity is less than the electron thermal velocity. Second, results of a computer simulation on the flow of a cylindrical beam and the resulting background plasma show that when the background neutral gas density is less than or approximately equal to a critical density as instability occurs. This critical density is the density that would be needed to space-charge neutralize the beam if the positive ions were not retarded by the beam. An approximate dispersion relation indicates that the nature of the instability is a transverse positive-ion acoustic wave which couples to the beam.

1977-09-22

381

Spin-density-wave transition and #mu#SR in the heavy-fermion Ce(Ru, T)_2Si_2, T = Rh, Pd  

International Nuclear Information System (INIS)

... 900526-11-8 277 p. MATERIALS SCIENCE antiferromagnetic materials cerium

1999-02-28

383

SEEK IGLOO Radar Clutter Study  

Science.gov (United States)

... 17 IV. Spatial Amplitude Distributions of Terrain and Sea.....23 Clutter V, Spectral Density Measurements ..... 53 A. Terrain Clutter ..... ...

1977-10-01

385

Plasma density ramp for relativistic self-focusing of an intense laser  

International Nuclear Information System (INIS)

It is known that a high-power laser propagating through an underdense plasma can acquire a minimum spot size due to relativistic self-focusing. Beyond the focus, the nonlinear refraction starts weakening, and the spot size of the laser increases, showing periodic self-focusing/ defocusing behavior with the distance of propagation. To overcome the defocusing, we propose the introduction of a localized upward plasma density ramp. In the presence of an upward ramp of plasma density, the laser beam obtains a minimum spot size and maintains it with only a mild ripple. For suitable parameters of the laser and the plasma, we have deduced conditions for the self-focusing. This kind of plasma density ramp may be observed in a gas-jet plasma experiment and resembles a plasma lens.

2007-05-01

386

Parametric Modeling of Low-Frequency Water-Vapor-Induced ...  

Science.gov (United States)

indicated for the phase spectral density measurements; how- ever, Ref. 7 provides a very tentative estimate of : ORW ~ 2 ><10"'(RW); Ta = 1000 seconds ...

387

Microfluidic local perfusion chambers for the visualization and manipulation of synapses  

UK PubMed Central (United Kingdom)

SummaryThe polarized nature of neurons as well as the size and density of synapses complicates the manipulation and visualization of cell biological processes that control synaptic...Full Text Available

2010-04-15

388

MTF ' MISSISSIPPI SOUND REMOTE SENSING STUDY I 19 SEPTEMBER 1972  

Science.gov (United States)

metric temperatures has been prepared showing the surface water temper- ... occasion, gray levels show different densities for similar water temper- ...

389

MAIN RESULTS OF ATMOSPHERIC FINE STRUCTURE PARAMETER OBSERVATION ...  

Science.gov (United States)

results of motion energy spectral density measurements in the upper atmosphere for the time interval of 5 minutes to 12 hours, in ...

390

L. V. BALDWIN &TAL BY  

Science.gov (United States)

L. V. BALDWIN &TAL. APPARATUS FOR INCREASING ION ENGINE BEAM DENSITY. Filed Jan. 4, 1963 ... Lionel V. Baldwin. Fort Collins. Colo.. and Vid A. ...

391

Ion Langmuir waves in a nonneutral plasma  

Energy Technology Data Exchange (ETDEWEB)

A nonneutral /sup 7/Li/sup +/ ion plasma is described in which ion Langmuir waves are observed for the first time. The properties of these waves near the Brillouin density limit are investigated.

1981-01-05

392

High Temperature Superconducting Compounds  

Science.gov (United States)

... Voltage noise power spectral density measurements as a function of temperature, frequency, current, and magnetic field on DyBa2Cu3O7.x (DBCO ...

1992-11-30

393

HDL in humans with cardiovascular disease exhibits a proteomic signature  

UK PubMed Central (United Kingdom)

BackgroundAlterations in protein composition and oxidative damage of high-density lipoprotein (HDL) have been proposed to impair the cardioprotective properties of...Full Text Available

2010-07-04

394

Ground state energies and nuclear density distribution in the coherent flucton model  

Energy Technology Data Exchange (ETDEWEB)

The coherent flucton model is applied to the description of some basic nuclear properties, such as: ground state energies, bond energies, nucleon momentum spectra, and nuclear density distributions. It is shown that the momentum distributions of the nucleons coincide with the Fermi distribution for small momenta and exhibit a well pronounced high energy ''tail'', thus providing inclusive reactions of pi-meson generations in kinematically forbidden areas at nucleon-nucleon collisions. Analytical expressions for the bond energy and nuclear density distribution are derived. An agreement with the experimentally obtained data is achieved. The model features are discussed referring to the processes, characterized mainly by the geometric and dynamic properties of the nuclei, as well as by nuclear density distribution. In particular, ion-ion scattering processes at high energy are considered.

1980-01-01

395

Ground state energies and nuclear density distribution in the coherent flucton model  

International Nuclear Information System (INIS)

The coherent flucton model is applied to the description of some basic nuclear properties, such as: ground state energies, bond energies, nucleon momentum spectra, and nuclear density distributions. It is shown that the momentum distributions of the nucleons coincide with the Fermi distribution for small momenta and exhibit a well pronounced high energy ''tail'', thus providing inclusive reactions of pi-meson generations in kinematically forbidden areas at nucleon-nucleon collisions. Analytical expressions for the bond energy and nuclear density distribution are derived. An agreement with the experimentally obtained data is achieved. The model features are discussed referring to the processes, characterized mainly by the geometric and dynamic properties of the nuclei, as well as by nuclear density distribution. In particular, ion-ion scattering processes at high energy are considered.

396

Femtosecond Laser Passivation of GaAs Detector Material  

Science.gov (United States)

... The approach is to perform noise spectral density measurements and selected materials structure measurements on GaAs detector materials, with ...

2008-06-07

397

Experimental and analytical study of saturation current density of laser-doped phosphorus emitters for silicon solar cells  

British Library Electronic Table of Contents (United Kingdom)

Heavily doped emitters with low saturation current density are of particular interest for selective emitter solar cells. These emitters can be obtained by laser doping through the phosphosilicate glass layer formed after thermal diffusion from POCl3 gas. The experimental results show that in contrast to purely POCl3 furnace-diffused emitters, the saturation current density of laser-doped emitters does not increase linearly as sheet resistance decreases, but rather features two distinct regimes. In one of these regimes, the saturation current density is found to decrease as the sheet resistance decreases, reaching values lower than those of furnace emitters. This peculiar behaviour was explained by both qualitative analysis and numerical simulations.

2011-01-01

398

Estimation of plasma density by surface plasmons for surface-wave plasmas  

International Nuclear Information System (INIS)

An estimation method of plasma density based on surface plasmons theory for surface-wave plasmas is proposed. The number of standing-wave is obtained directly from the discharge image, and the propagation constant is calculated with the trim size of the apparatus in this methods, then plasma density can be determined with the value of 9.1 x 1017 m-3. Plasma density is measured using a Langmuir probe, the value is 8.1 x 1017 m-3 which is very close to the predicted value of surface plasmons theory. Numerical simulation is used to check the number of standing-wave by the finite-difference time-domain (FDTD) method also. All results are compatible both of theoretical analysis and experimental measurement. (authors)

2008-12-01

399

Electronic structure, Compton profiles and optical properties of TaC and TaN  

International Nuclear Information System (INIS)

Isotropic Compton profiles of TaC and TaN have been measured for the first time, at an intermediate resolution, using 662 keV #gamma#-radiation. Energy bands, density of states and Fermi surface topology of TaC and TaN have been computed using linear combination of atomic orbitals with density functional theory and full potential linearised augmented plane wave method. Both band structure calculations predict the metallic character of TaC and TaN. The electron momentum densities calculated using various approaches of density functional theory are compared with the present measurements. On the basis of Mulliken's population, it is also seen that TaC has more covalent bonding than TaN. The optical properties computed using full potential linearised augmented plane wave method are explained in terms of intraband transitions.

2010-11-01

400

Design and Evaluation of a Reinforced Advanced-Grid ...  

Science.gov (United States)

... kg/m3 density. The Rohacell foam displayed an average ultimate compressive strength of 1546 kPa. The maximum load ...

2011-05-14

401

Density functional theory studies of energetic nitrogen-rich derivatives of substituted carbon-bridged diiminotetrazoles  

British Library Electronic Table of Contents (United Kingdom)

Density functional theory calculations were performed to study the effects of different substituents and bridge groups on the heats of formation (HOFs), thermal stability, and detonation properties for a series of diiminotetrazole derivatives. The isodesmic reaction method was employed to calculate the HOFs of the derivatives using total energies obtained from electronic structure calculations. The bond dissociation energies and bond orders for the weakest bonds were analyzed to investigate the thermal stability of the diiminotetrazole derivatives. The detonation velocities and pressures were evaluated by using the semiempirical Kamlet-Jacobs equations, based on the theoretical densities and HOFs. These results provide basic information for the molecular design of novel high-energy density...

2011-01-01

402

Density Gradients for Isolation of Mononuclear Blood Cells for ...  

Science.gov (United States)

... to-continuum X-ray intensity ratio [5]. For ence in the means [7]. In addition, washing samples on thin films, the characteristic X- lymphocytes in NH ...

2011-05-15

403

Decreased dendritic spine density and abnormal spine morphology in Fyn knockout mice  

British Library Electronic Table of Contents (United Kingdom)

Fyn is a Src-family tyrosine kinase that affects long term potentiation (LTP), synapse formation, and learning and memory. Fyn is also implicated in dendritic spine formation both in vitro and in vivo. However, whether Fyn's regulation of dendritic spine formation is brain-region specific and age-dependent is unknown. In the present study, we systematically examined whether Fyn altered dendritic spine density and morphology in the cortex and hippocampus and if these effects were age-dependent. We found that Fyn knockout mice trended toward a decrease in dendritic spine density in cortical layers II/III, but not in the hippocampus, at 1month of age. Additionally, Fyn knockout mice had significantly decreased dendritic spine density in both the cortex and hippocampus at 3months and 1year, an...

2011-01-01

404

Corn pollen deposition on milkweeds in and near cornfields  

UK PubMed Central (United Kingdom)

The density of corn pollen on leaves of milkweed plants inside and outside of cornfields was measured in several studies from different localities. The purpose was to obtain a representative picture...Full Text Available

2001-10-09

405

Competition between Elymus elymoides and Taeniatherum caput-medusae - Field Data  

Science.gov (United States)

The data were collected over three growing seasons. They include density, vegetative biomass, and seed biomass of the two species within the plots. There ... ...

406

Comparing Genomes within the Species Mycobacterium tuberculosis  

UK PubMed Central (United Kingdom)

The study of genetic variability within natural populations of pathogens may provide insight into their evolution and pathogenesis. We used a Mycobacterium tuberculosis high-density...Full Text Available

2001-04-01

407

Bonding and microstructural stability in Ni55Ti45 studied by experimental and theoretical methods  

Energy Technology Data Exchange (ETDEWEB)

Spiral orbit tribometry friction tests performed on Ni-rich Ni55Ti45 titanium ball bearings indicate that this alloy is a promising candidate for future aerospace bearing applications. Microstructural characterization of the bearing specimens was performed using transmission electron microscopy and energy dispersive spectroscopy, with NiTi, Ni4Ti3, Ni3Ti, and Ni2Ti4Ox phases identified within the microstructure of the alloy. Density functional theory was applied to predict the electronic structure of the NixTiy phases, including the band structure and site projected density of states. Ultraviolet photoemission spectroscopy was used to verify the density of states results from the density functional theory calculations, with good agreement observed between experiment and theory.

2010-11-25

408

Apolipoproteins in rat serum and renal lymph.  

UK PubMed Central (United Kingdom)

The concentration of apolipoproteins was measured by quantitative immunoelectrophoresis in rat serum, in the lipoprotein-free ultracentrifugal fraction (density greater than 1.21) of serum, and in renal...Full Text Available

1976-05-01

411

AERODYNAMIC NOISE TESTS ON X-20 SCALE MODELS. ...  

Science.gov (United States)

... 37 18 Power Spectral Density Measurements of Buffet Pressures for Two Different Microphone Positions Compared with PSD Values Inferred from ...

1965-11-01

412

A Bibliography of the Physical Equilibria and Related ...  

Science.gov (United States)

... 3. Critical constants, and triple point 4. Compressibility isothermE S. Density, molar volume (of a condensed phase) 6. Equations of state, general ...

1960-05-01

413

[Hormonal disorders in chronic alcoholic intoxication].  

Science.gov (United States)

Hormone levels were examined in the venous blood in 54 men suffering from stage 2 alcoholism and in 30 normal subjects, using a radioimmunochemical assay. The alcoholics were found to have a statistically significant increase in prolactin and a decrease in testosterone. A definite ratio in the secretion of these hormones differing from that in the control group was elucidated. This ratio (prolactin-testosterone index) is proposed as a diagnostic test of alcoholism. PMID:6441404

1984-01-01

414

Voronoi distance based prospective space-time scans for point data sets: a dengue fever cluster analysis in a southeast Brazilian town  

UK PubMed Central (United Kingdom)

BackgroundThe Prospective Space-Time scan statistic (PST) is widely used for the evaluation of space-time clusters of point event data. Usually a window of cylindrical shape is employed,...Full Text Available

415

Toward efficient excavators  

Energy Technology Data Exchange (ETDEWEB)

This article deals with excavation equipment used in open-pit mining operations. Because of competition in the mining industry, a demand for more energy-efficient excavators is being felt. The authors present different types of machinery and give statistics on energy use, weights, bucket capacity, and maximum digging depths. Actual manufacturers specifications are also given for different models. A short discussion on the role computers are playing in this new technology is also given.

1984-05-01

416

Time-resolved measurement of a self-amplified free-electron laser  

International Nuclear Information System (INIS)

We report on a time-resolved measurement of self-amplified spontaneous emission free-electron laser (FEL) pulses. We observed that the spikes in such FEL pulses have an intrinsic positive chirp and the energy chirp in the electron bunch mapped directly into the FEL output. The measurement also provides rich information on the statistics of the FEL pulses.

2003-07-11

417

Thermal reactor safety  

International Nuclear Information System (INIS)

Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport.

1990-09-01

418

Thermal reactor safety  

Energy Technology Data Exchange (ETDEWEB)

Information is presented concerning new trends in licensing; seismic considerations and system structural behavior; TMI-2 risk assessment and thermal hydraulics; statistical assessment of potential accidents and verification of computational methods; issues with respect to improved safety; human factors in nuclear power plant operation; diagnostics and activities in support of recovery; LOCA transient analysis; unresolved safety issues and other safety considerations; and fission product transport.

1980-06-01

419

The nucleon axial charge in full lattice QCD  

Energy Technology Data Exchange (ETDEWEB)

The nucleon axial charge is calculated as a function of the pion mass in full QCD. Using domain wall valence quarks and improved staggered sea quarks, we present the first calculation with pion masses as light as 354 MeV and volumes as large as (3.5 fm)3. We show that finite volume effects are small for our volumes and that a constrained fit based on finite volume chiral perturbation theory agrees with experiment within 5% statistical errors.

2005-10-13

420

The method of medians in the problem of ranking interval objects specified by three points  

British Library Electronic Table of Contents (United Kingdom)

A method for ranking interval objects is proposed and analyzed; the characteristics of those objects are represented by pessimistic, optimistic, and most probable estimates. The method is based on the approximation of the binary probability preference relation by the binary median preference relation. The method is verified using statistical modeling (the Monte Carlo method). The proposed approach can be used for ranking nonreusable and reusable objects.

2011-01-01

421

The influence of intramolecular H-bond on chromatographic behavior of phenylalkylamines  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption on the surface of graphitized thermal carbon black at 300 K were determined by the molecular statistical method for three phenylalklylamines. The influence of the intramolecular H-bond on the conformation of the molecules compared with structurally related n-alkyl-benzenes was considered. It was shown that the conformations of the molecules could influence chromatographic retention. Conformational isomers stabilized by intramolecular H-bonds were found to retain their structure in adsorption on graphitized thermal carbon black.

2009-01-01

422

The influence of intramolecular H-bond on chromatographic behavior of phenylalkylamines  

Science.gov (United States)

The thermodynamic characteristics of adsorption on the surface of graphitized thermal carbon black at 300 K were determined by the molecular statistical method for three phenylalklylamines. The influence of the intramolecular H-bond on the conformation of the molecules compared with structurally related n-alkyl-benzenes was considered. It was shown that the conformations of the molecules could influence chromatographic retention. Conformational isomers stabilized by intramolecular H-bonds were found to retain their structure in adsorption on graphitized thermal carbon black.

2009-04-01

423

The influence of an intramolecular H-bond on the adsorption of sulfur-containing amino acids on graphitized thermal carbon black  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption of sulfur-containing amino acids and their derivatives on the surface of graphitized thermal carbon black were calculated by the molecular statistical method. The parameters of the atom-atom potential function of intermolecular interaction between the S atom in amino acids and the graphite C atom were determined. It was shown that an intramolecular H-bond influenced the adsorption of amino acids on the surface of graphitized thermal carbon black.

2009-01-01

424

The influence of an intramolecular H-bond on the adsorption of sulfur-containing amino acids on graphitized thermal carbon black  

Science.gov (United States)

The thermodynamic characteristics of adsorption of sulfur-containing amino acids and their derivatives on the surface of graphitized thermal carbon black were calculated by the molecular statistical method. The parameters of the atom-atom potential function of intermolecular interaction between the S atom in amino acids and the graphite C atom were determined. It was shown that an intramolecular H-bond influenced the adsorption of amino acids on the surface of graphitized thermal carbon black.

2009-04-01

425

The effects of high voltage transmission lines on the health of adjacent resident populations  

Energy Technology Data Exchange (ETDEWEB)

A community health survey of 438 individuals was taken to detect health problems related to high voltage electrical transmission among an adjacent residential population. Results revealed no significant or consistent relationships between exposure to a high voltage DC power line and the perceived health problems that were measured. The sample was not, however, large enough to draw statistically significant conclusions regarding possible health effects with a very low incidence.

1984-01-01

426

The content of natural radioactive materials in phosphate fertilizers and their contribution to the radiation exposure of the human population  

International Nuclear Information System (INIS)

The Ra, Th, and K-40 content of the most important phosphate fertilizers used and authorized in the FRG was determined by #gamma#-spectroscopy. The results, together with statistical data on the consumption and use of fertilizers, were used for an estimation of the contribution of #gamma#-radiation from phosphate fertilizers to the external population exposure in the FRG. (orig./AK).

1974-09-23

427

The International Index of Erectile Function: A Methodological Critique and Suggestions for Improvement  

British Library Electronic Table of Contents (United Kingdom)

The International Index of Erectile Function is a well-worded and psychometrically valid self-report questionnaire widely used as the standard for the evaluation of male sexual function. However, some conceptual and statistical problems arise when using the measure with men who are not sexually active. These problems are illustrated using 2 empirical examples, and the authors provide recommended solutions to further strengthen the efficacy and validity of this measure.

2011-01-01

428

Study of a 5 kW PEMFC using experimental design and statistical analysis techniques  

Energy Technology Data Exchange (ETDEWEB)

Within the framework of the French inter lab SPACT project (Fuel Cell Systems for Transportation Applications), the behavior of a 5 kW PEM fuel cell stack, fed by humidified hydrogen and compressed air, is investigated in a test platform at Belfort, France. A set of polarization curves are recorded, under various conditions of stack temperature, gas pressure, and stoichiometry rates, in order to obtain a kind of cartography, representing the static stack performance. Initially, the tests are defined considering experimental design techniques. In order to study the relative impacts of the physical factors on the fuel cell voltage, some polarization curve results are selected from the static tests available applying experimental design methodology. First, several analyses are used to estimate the impact of the stack temperature, gas pressure, and stoichiometry rate on the fuel cell voltage. Statistical sensitivity analyses (ANOVA) are used to compute, from the ...

2007-02-15

429

Statistical mechanics and thermodynamics for tachyons  

International Nuclear Information System (INIS)

Momentum- and speed-dependent Maxwell-Boltzmann equilibrium distributions have been derived for tachyons and compared with the corresponding relativistic distributions. This is followed by a calculation of the mean, most probable and r.m.s. speeds for both the relativistic and tachyonic distributions. The ideal gas of tachyons is discussed, including calculations of the internal energy and entropy. In each case a comparison is made with the corresponding bradyonic results. It is found that tachyons behave just like bradyons in the high-temperature limit, but have markedly different behaviour at low temperatures.

430

Specific needs for evaluation methods in energy policy and planning; Konkrete behov for vurderingsmetoder i energipolitikken og energiplanlaegningen  

Energy Technology Data Exchange (ETDEWEB)

Energy sector is relatively easy to evaluate economically. There have existed reliable statistics on energy systems and consumption and the planning has been based on them. However the environmental factors have been integrated into the Danish energy policy first in the nineties, and the new socio-economic evaluations have to take the pollution abatement measures into account. (EG)

1995-09-01

431

Spatial dependency of V. cholera prevalence on open space refuse dumps in Kumasi, Ghana: a spatial statistical modelling  

UK PubMed Central (United Kingdom)

BackgroundCholera has persisted in Ghana since its introduction in the early 70's. From 1999 to 2005, the Ghana Ministry of Health officially reported a total of 26,924 cases and...Full Text Available

432

Some problems to enhance reliability and safety of foreign NPP  

International Nuclear Information System (INIS)

Statistical data on individual types of foreign NPPs including reliability and safety indices are given. It is noted that capacity factors (CF) in 1985 were higher for PWRs. Japan has the highest CF-98.5% in the world. One of main causes of NPP shutdown remains the primary circuit equipment failure in connection with different corrosion types (intercrystalline, pitting, denting-corrosion etc.). Effect of all volatile treatment on enhancement of NPP reliabiity is shown. Technical BWR characteristics are presented.

433

Simulation of oil and gas production forecasts using smoothing methods  

Energy Technology Data Exchange (ETDEWEB)

A variety of forecasting approaches have been used in the energy area. Forecast simulations provide a common basis for comparing the relative precision of different forecasting methods. This paper presents a forecast simulation made using smoothing procedures for forecasting time series. The simulation design, statistical analysis, and conclusions are provided.

1987-01-01

434

Second quantization of fields associated with spin-1 tachyons  

Energy Technology Data Exchange (ETDEWEB)

Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. 15 refs.

1982-01-01

435

Second quantization of fields associated with spin-1 tachyons  

International Nuclear Information System (INIS)

Lorentz invariant theory of second quantization of superluminal electromagnetic fields has been constructed in purely group theoretical manner by using the reduced expansion of four-vector fields for imaginary mass system in terms of standard helicity representations of Poincare group. It has been shown that the usual relationship of spin and statistics need not be inverted for Lorentz invariance of the theory of spin-1 tachyons. (author).

436

Renewable energies in France: the main 2001 results; Les energies renouvelables en France: les principaux resultats en 2001  

Energy Technology Data Exchange (ETDEWEB)

This 2001 status on the use of renewable energies in France makes a synthesis of the electric and heat productions of renewable origin. It lists the primary or secondary productions of renewable energies, and details the uses corresponding to each renewable energy production source and their respective satisfaction of consumer's needs (residential, industry and agriculture sectors). A detail statistical status for 1999, 2000 and 2001 is presented in tables. (J.S.)

2002-05-01

437

Phase transitions in multiplicative competitive processes  

Science.gov (United States)

We introduce a discrete multiplicative process as a generic model of competition. Players with different abilities successively join the game and compete for finite resources. Emergence of dominant players and evolutionary development occur as a phase transition. The competitive dynamics underlying this transition is understood from a formal analogy to statistical mechanics. The theory is applicable to bacterial competition, predicting novel population dynamics near criticality.

2005-07-01

438

Peculiarity of counterion - polyion interactions in aqueous solutions of copolymers of acrylamide with cadmium acrylate  

Energy Technology Data Exchange (ETDEWEB)

Binding of Cd/sup 2 +/ ions in aqueous solutions of statistical copolymers of acrylamide with cadmium acrylate with different content of ionogenic groups in copolymers was investigated by polarography, conductometry, viscometry and dialysis. It is shown that the degree of binding of Cd/sup 2 +/ ions increases with increasing of the content of ionogenic groups in the copolymer and with decreasing of ionic strength of the solution. The values of the degree of binding of Cd/sup 2 +/ ions obtained by polarography and dialysis show satisfactory agreement.

1984-02-01

439

Oxygen-induced enhancement of the adsorptive capacity of activated charcoal  

Energy Technology Data Exchange (ETDEWEB)

Adsorption isotherms for phenol and o-cresol on activated charcoal at neutral pH and several dissolved oxygen concentrations were conducted at 23{degree}C. Significant improvements in capacities were observed with increasing dissolved oxygen concentrations for the two adsorbates. These statistically-significant additional capacities were not due to biological activities but merely due to surface chemical reactions. The improvement in capacity was directly related to the amount of oxygen per unit mass of GAC.

1992-02-01

440

Optimal Knot Selection for Least-squares Fitting of Noisy Data with Spline Functions  

Energy Technology Data Exchange (ETDEWEB)

An automatic data-smoothing algorithm for data from digital oscilloscopes is described. The algorithm adjusts the bandwidth of the filtering as a function of time to provide minimum mean squared error at each time. It produces an estimate of the root-mean-square error as a function of time and does so without any statistical assumptions about the unknown signal. The algorithm is based on least-squares fitting to the data of cubic spline functions.

2008-05-15

441

Optical and statistical model calculation of the americium 242m capture cross section  

International Nuclear Information System (INIS)

The capture cross sections of Am 242m can be deduced from resonances analysis at low energy and computed with theoretical models at high energy. In this work, a coherent set of cross sections which reproduced the experimental values of the fission cross sections is computed. These calculations were performed for an energy of the incoming neutron between 1 keV and 1 MeV.

442

Ocean waves: energy resource assessment  

Energy Technology Data Exchange (ETDEWEB)

The aim of this paper is to provide a general view of wave energy resource assessment. First, a review of the origin of waves and the transformation they undergo as they propagate towards the coast through waters of decreasing depth is presented. Following this, the wave and wave-energy parameters and the statistics required for resource characterization are described. The various types of wave data and their usefulness for the present purposes are summarised. A common methodology for assessment of the wave energy resource is developed. Finally, a general description of the global open ocean resource is presented.

2002-12-31

443

Occupational exposure information system in Daya Bay Nuclear Power Station  

International Nuclear Information System (INIS)

This paper introduces an occupational exposure information system in detail, which is developed and in operation presently by Daya Bay nuclear power plant. It is presented in the paper that individual dose monitoring items and method, design and classification of database configuration, statistics and analysis of individual dose, and management of staff entering and exiting controlled area. The system is instructive to analysing individual dose and optimizing radiation protection measures. (authors)

2005-07-01

444

No difference in antibody titers against xenotropic MLV related virus in prostate cancer cases and cancer-free controls  

British Library Electronic Table of Contents (United Kingdom)

New ELISA assays were developed to measure immunoreactivity for XMRV. Antibody titers were measured in a cohort of prostate cancer cases and cancer free controls from the central United States. No statistically significant differences were observed in immunoreactivity between cases and controls for either the XMRV-env or the XMRV-gag antigen.

2011-01-01

445

Neutron radiography with the cyclotron, 6  

International Nuclear Information System (INIS)

The image processing system for the dynamic neutron radiography has been developed. It is based on the hardware subset, composed by the method of the pipe-line and use of algorithm of local statistics. The processing speed per one pixel is shorter than 100 n sec and video-rate processing can be executed on it. Some image processes for improving the quality of the real-time neutron image, noise reduction and contrast stretching would be attempted by the use of this system. (author).

1988-01-01

446

NAME=\\  

Wastenet

... The relation between turbulence structure and a scalar detected using a new statistical test for the change in fractal dimension of a time-series, Department of Geography, University of Durham Workshop on Coherent Structures in Rivers Keylock C.J., Nishimura K., Nemoto M., Ito Y. 2006. The wake structure from fractal fences: implications for the control of turbulent suspensions, Warwick Turbulence ...

447

Molecular statistical calculations of the adsorption of proline and its hydroxy derivatives on graphitized thermal carbon black  

British Library Electronic Table of Contents (United Kingdom)

The thermodynamic characteristics of adsorption of proline and its hydroxy derivatives on the surface of graphitized thermal carbon black (GTCB) were calculated. The arrangement of hydroxyl groups in the amino acid molecule was shown to influence their adsorption on GTCB. The influence of internal rotation angles in proline and its hydroxy derivative molecules on their adsorption on GTCB was studied.

2009-01-01

448

Molecular statistical calculations of the adsorption of proline and its hydroxy derivatives on graphitized thermal carbon black  

Science.gov (United States)

The thermodynamic characteristics of adsorption of proline and its hydroxy derivatives on the surface of graphitized thermal carbon black (GTCB) were calculated. The arrangement of hydroxyl groups in the amino acid molecule was shown to influence their adsorption on GTCB. The influence of internal rotation angles in proline and its hydroxy derivative molecules on their adsorption on GTCB was studied.

2009-04-01

449

Moderate deviations for stationary sequences of Hilbert valued bounded random variables  

CERN Document Server

In this paper, we derive the moderate deviation principle for stationary sequences of bounded random variables with values in a Hilbert space. The conditions obtained are expressed in terms of martingale-type conditions. The main tools are martingale approximations and a new Hoeffding inequality for non adpated sequences of Hilbert-valued random variables. Applications to Cramer-Von Mises statistics, functions of linear processes and stable Markov chains are given.

2008-01-01

450

Modeling dependent failures for the availability of extra high voltage transmission lines  

Energy Technology Data Exchange (ETDEWEB)

This paper investigates the calculation of availability for parallel transmission lines (two or more) in the same tower or on the same right of way. As in many studies, the development of mathematical models is an important step. The models are justified using historical data and known characteristics of power system elements. A statistical method was used to generalize the failure rate and repair rate from real operating data. Application of the new model (which combines common-mode, simultaneous independent, and dependent outages) is discussed.

1989-06-01

451

Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemistry in the region of Iridium and Gold  

International Nuclear Information System (INIS)

We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from osmium (Z = 76) to gold (Z = 79). Of particular interest are the cross sections on Ir and Au including reactions on isomeric targets.

2008-02-01

452

Method for processing statistical information concerning sucker-rod pump unit operations  

Energy Technology Data Exchange (ETDEWEB)

The authors propose an integrated indicator of pump-rod couplings that allows both the couplings and the pump operations to be appraised according to the given formula. (Formula provided). The dynamic relationships of rod operations were determined with nomographs. These relationships involve such factors as: the type and size of the sucker-rod string; the pressure load at the equalizer head and its correlation to threshold pressure at pump discharge; pump diameter; the rod weight and construction; and integral reliability indicators.

1982-01-01

453

Irradiation test program for FFTF  

International Nuclear Information System (INIS)

Four unique deisgn features are described which make the Fast Flux Test Facility eminently suitable for irradiation test programs. These features are a fast flux level of 7 x 10"1"5 neutrons/cm"2/sec, a 36-inch reference (breeder reactor) core height, test volumes suitable for testing of statistical quantities of materials, and the capability for direct (contact) or indirect (proximity) instrumentation of active core experiments.

454

In Pursuit of Spreadsheet Excellence  

CERN Document Server

The first fully-documented study into the quantitative impact of errors in operational spreadsheets identified an interesting anomaly. One of the five participating organisations involved in the study contributed a set of five spreadsheets of such quality that they set the organisation apart in a statistical sense. This virtuoso performance gave rise to a simple sampling test - The Clean Sheet Test - which can be used to objectively evaluate if an organisation is in control of the spreadsheets it is using in important processes such as financial reporting.

2008-01-01

455

Improved measurement of $\\psi (2S)$ decays into $\\tau ^{+}\\tau ^{-}$  

CERN Document Server

Using 14M $\\psi (2S)$ events collected at BESII, the branching fraction of $\\psi (2S)\\to \\tau ^{+}\\tau ^{-}$ is measured to be $Br_{\\tau \\tau}=(3.10\\pm 0.21\\pm 0.38)\\times 10^{-3}$, where the first error is statistical and the second is systematic.

2006-01-01

456

Geosynchronous orbit magnetopause crossings  

Energy Technology Data Exchange (ETDEWEB)

In this study we extend the analysis of magnetopause crossings observed with Magnetospheric Plasma Analyzer measurements to examine a much larger statistical data set. This study examines 39 maiznetosheath/LLBL intervals from 79 spacecraft-months of observations: these observations were taken from a survey of data from the start of each spacecraft mission and extending through March 1993. In contrast to the previous findings, we find no evidence for a significant dawn/dusk asymmetry in geosynchronous magnetopause crossings.

1994-07-01

457

Financial statistics of major US publicly owned electric utilities 1994  

Energy Technology Data Exchange (ETDEWEB)

This publication presents 5 years (1990--94) of summary financial data and current year detailed financial data on the major publicly owned electric utilities. Generator and nongenerator summaries are presented. Composite tables present: Aggregates of income statement and balance sheet data, financial indicators, electric operation and maintenance expenses, electric utility plant, number of consumers, sales of electricity, and operating revenue, and electric energy account data.

1995-12-15

458

FY 1999 Laboratory Directed Research and Development annual report  

Energy Technology Data Exchange (ETDEWEB)

A short synopsis of each project is given covering the following main areas of research and development: Atmospheric sciences; Biotechnology; Chemical and instrumentation analysis; Computer and information science; Design and manufacture engineering; Ecological science; Electronics and sensors; Experimental technology; Health protection and dosimetry; Hydrologic and geologic science; Marine sciences; Materials science; Nuclear science and engineering; Process science and engineering; Sociotechnical systems analysis; Statistics and applied mathematics; and Thermal and energy systems.

2000-06-13

459

Evaluating and improving the operating reliability of the units of sucker rod well pumps  

Energy Technology Data Exchange (ETDEWEB)

The theory of reliability is used to develop statistical field data on malfunctions of units of sucker rod well pumps (UShSN). The indices of reliability of the UShSN are applied for establishment of the cause-effect links between the operating factors. Dependences of operating time on the depth of suspension of the pumps, mode of pumping out, degree of flooding of the oil, and twisting of the shafts are established for conditions of specific fields. The obtained relationships can be used in selecting and optimizing the work of the UShSN.

1982-01-01

460

Energy on the Web  

Energy Technology Data Exchange (ETDEWEB)

Contains Executive Summary and Chapters on: Energy and the Internet; Internet Developments; Search Guide; Oil and Gas Industry; Electricity and Utilities; Nuclear Energy; Coal Industry; Alternative Energy; Government and Supranational Agencies; Research Institutions and Universities; Energy Statistics; Commodity Pricing and financial Markets; Company Information; Country Information; Associations; Engineering; Environment; Patents, Trademarks and Standards; News; Industry Events; Miscellaneous. (Author)

1999-10-01

461

Energy flux operator, current conservation and the formal Fourier's law  

International Nuclear Information System (INIS)

By revisiting previous definitions, we show that one can define an energy current operator that satisfies the continuity equation for a general Hamiltonian in one dimension. This expression is useful for studying electronic, phononic and photonic energy flow in linear systems and in hybrid structures. The definition allows us to deduce the necessary conditions that result in current conservation for general-statistics systems. The discrete form of the Fourier's law of heat conduction naturally emerges in the present definition.

2009-01-16

462

Effects of electric field on the II-III phase transition in lithium ammonium sulphate and its deuterated analogue  

International Nuclear Information System (INIS)

Experimental results are presented on the quasi-statistic polarization reversal and on the effect of high dc electric field on the behaviour of LiNH_4SO_4 and LiND_4SO_4 monocrystals, namely in the vicinity of the II-III phase transformation.

1984-03-01

463

Design and operation of a quadruple effect evaporator with concentrator  

Energy Technology Data Exchange (ETDEWEB)

For the sugar industry, a new system of multiple-effect evaporation consuming minimal steam has been designed by means of a mathematical model and its advantages and characteristics are analysed. A way is found to overcome difficulty in operation and instability of the amount of steam consumed. Statistical data obtained using the new system are compared with the old system and show an economic profit as well as confirming the validity of the model. (author)

1993-02-01

464

Coherence and statistical properties of photon beams with application to the free-electron laser  

International Nuclear Information System (INIS)

The subject of quantum optics has undergone considerable development in the last twenty-five years. Spurred by the invention of the laser, the theoretical understanding of the coherence and statistical properties of optical beams has now attained a stage of maturity where it is possible to treat different kinds of light sources. Over approximately the latter half of this period of development in quantum optics, the free-electron laser (FEL) has been developed to the point where it is now regarded as a tunable light source of considerable versatility, with prospects of producing radiation over a wide range of wavelengths at large levels of power. Since the basic mechanism for radiation gain in an FEL can be understood in classical terms, much of the literature on the subject does not need to venture outside the domain of classical physics. However, it is natural that the coherence and statistical properties of photon beams produced by FEL's ...

465

Clinical Significance of Renal Pelvic Dilatation less than 10 mm in Neonates: Correlation with Urinary Tract Infection and Vesicoureteral Reflux  

Energy Technology Data Exchange (ETDEWEB)

We wanted to evaluate the correlation of mild renal pelvic dilatation (RPD) that is observed to be less than 10 mm on ultrasound (US) with urinary tract infection (UTI) and vesicoureteral reflux (VUR) in neonates. We reviewed 137 kidneys of 107 neonates who had RPD less than 10 mm on US. All the kidneys were divided into two groups: Group I (RPD <= 5.0 mm) and Group II (RPD > 5.0 mm), and we statistically analyzed the RPD change according to UTI and VUR. Seven neonates had VUR (5.1%), and there was no statistical significance between Group I (6 neonates, 5.6%) and Group II (1 neonate, 3.3%). Thirty seven cases (27%) had UTI and there was no statistical significance between Group I (30 cases, 28.0%) and Group II (7 cases, 23.3%). The RPD did not change in 81.8% of the cases, it increased in 4.4% of the cases and it decreased in 13.9% of the cases on follow up US. The incidence of VUR and UTI were not different ...

2009-12-15

466

Circadian and circatrigintan respiratory and related intermodulations in the crab Barytelphusa guerini.  

Science.gov (United States)

Respiration and related physiologic variables in different tissues of Barytelphusa guerini and the respiration of this freshwater crab as a whole are closely synchronized in phase and in frequency along the circadian scale, in the face of large differences in circadian amplitude. A very close timing of most of the 36 variables examined in 2 separate circadian profiles and a modulation of some of these variables in added profiles as a function of lunar stage are clearly demonstrable, statistically significant and illustrative of time relations at 2 interacting frequencies. PMID:6745009

467

Calculation of henry constants for the adsorption of isomeric phenylenediamines on graphitized thermal carbon black  

British Library Electronic Table of Contents (United Kingdom)

Henry constants for the adsorption of o- and p-phenylenediamines on the surface of graphitized thermal carbon black within the temperature range 433?479 K were calculated by the molecular statistical method. The parameters of the atom-atom potential function of intermolecular interaction between the nitrogen atom in aniline and isomeric phenylenediamines and the carbon atom of the basal face of graphite were determined. It was shown that an intramolecular H bond influenced the geometry and adsorption properties of o-phenylenediamine.

2009-01-01

468

Calculation of henry constants for the adsorption of isomeric phenylenediamines on graphitized thermal carbon black  

Science.gov (United States)

Henry constants for the adsorption of o- and p-phenylenediamines on the surface of graphitized thermal carbon black within the temperature range 433-479 K were calculated by the molecular statistical method. The parameters of the atom-atom potential function of intermolecular interaction between the nitrogen atom in aniline and isomeric phenylenediamines and the carbon atom of the basal face of graphite were determined. It was shown that an intramolecular H bond influenced the geometry and adsorption properties of o-phenylenediamine.

2009-12-01

469

Battery Life Estimator Manual Linear Modeling and Simulation  

Energy Technology Data Exchange (ETDEWEB)

The Battery Life Estimator (BLE) Manual has been prepared to assist developers in their efforts to estimate the calendar life of advanced batteries for automotive applications. Testing requirements and procedures are defined by the various manuals previously published under the United States Advanced Battery Consortium (USABC). The purpose of this manual is to describe and standardize a method for estimating calendar life based on statistical models and degradation data acquired from typical USABC battery testing.

2009-08-01

470

Amazon.com: Social research & statistics: Books  

Wastenet

... Zaino (Paperback - July 28, 2010) Buy new: $58.95 $37.85 69 Used & new from $20.94 Get it by Thursday, Sept. 8 if you order in the next 1 hour and choose one-day shipping. Eligible for FREE Super Saver Shipping. (3) Other Formats: Paperback ...

471

A search for tachyons in cosmic ray showers  

International Nuclear Information System (INIS)

A search has been made of tachyons associated with cosmic ray showers of energies about 10"1"5 eV by searching for any precursor effects observed in plastic scintillator detectors. Detection thresholds well below most other similar experiments have been reached but no statistically significant effects have been found.

472

A prospective evaluation of the safety and efficacy of the TAXUS Element paclitaxel-eluting coronary stent system for the treatment of de novo coronary artery lesions: Design and statistical methods of the PERSEUS clinical program  

UK PubMed Central (United Kingdom)

BackgroundPaclitaxel-eluting stents decrease angiographic and clinical restenosis following percutaneous coronary intervention compared to bare metal stents. TAXUS Element is a third-generation...Full Text Available

473

Theoretical study of subwavelength imaging by acoustic metamaterial slabs  

CERN Document Server

We investigate theoretically subwavelength imaging by acoustic metamaterial slabs immersed in the liquid matrix. A near-field subwavelength image formed by evanescent waves is achieved by a designed metamaterial slab with negative mass density and positive modulus. A subwavelength real image is achieved by a designed metamaterial slab with simultaneously negative mass density and modulus. These results are expected to shed some lights on designing novel devices of acoustic metamaterials.

2009-01-01

474

The analysis of coupled heat and particle transport in Tokamaks by means of Fourier transform  

Energy Technology Data Exchange (ETDEWEB)

A method to deduce the 2 x 2 transport matrix for coupled heat and particle transport in Tokamaks is proposed. The method applies to perturbative experiments, and is based on a Fourier transform of the measured signals of temperature and density. By analyzing different linear combinations of temperature and density, the eigenvectors and eigenvalues of the transport matrix are determined. The method is tested for a number of illustrative cases using simulated data, and the sensitivity to noise on the signals is evaluated. (author).

1992-04-01

475

The JET (Joint European Torus) multipellet launcher and fueling of JET plasmas by multipellet injection  

Energy Technology Data Exchange (ETDEWEB)

A new multipellet long-pulse plasma fueling system is in operation on JET. In the initial experimental phase, a variety of plasma density profile shapes have been produced with peak to average values ranging up to 2.5 and peak plasma density up to 1.2 )times) 10/sup 20/m/sup )minus/3). 7 refs., 4 figs

1988-01-01

476

Representations of the conformal Lie algebra in the space of tensor densities on the sphere  

CERN Document Server

Let ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ be the space of tensor densities on $\\mathbb{S}^n$ of degree $\\lambda$. We consider this space as an induced module of the nonunitary spherical series of the group $\\mathrm{SO}_0(n+1,1)$ and classify $(\\mathrm{so}(n+1,1),\\mathrm{SO}(n+1))$-sim$unitary submodules of ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ as a function of $\\lambda$.

2003-01-01

477

Recovery Effects of a 180?mT Static Magnetic Field on Bone Mineral Density of Osteoporotic Lumbar Vertebrae in Ovariectomized Rats  

UK PubMed Central (United Kingdom)

The effects of a moderate-intensity static magnetic field (SMF) on osteoporosis of the lumbar vertebrae were studied in ovariectomized rats. A small disc magnet (maximum magnetic flux density 180 mT)...Full Text Available

2011-01-01

478

Power density distribution by gamma scanning of fuel rods measurement technique in RA-8 critical facility  

International Nuclear Information System (INIS)

Power density measurements in the critical facility RA-8 are presented. These measurements were the first systematic use of the reactor. A measurement system was designed, built and proved for this goal. Power profiles are showed and the results are compared with calculated values. (author)

1999-10-26

479

Polybutylene terephthalate on metals: a density functional theory and cluster models investigation  

Energy Technology Data Exchange (ETDEWEB)

The strength of adhesion of polybutylene terephthalate (PBT) on aluminium is investigated using density functional theory-based energy calculations. The aluminium atom is connected to a PBT monomer at different orientations, and total energies are calculated and compared to determine the most stable orientation. The binding is strongest when the Al is oriented at 180{sup 0} to the ester group of the monomer. Using this orientation as a basis, PBT adhesion on Ti, Ag, and Au is also investigated.

2006-02-01

480

Particle creation, inflation, and cosmic isotropy  

Energy Technology Data Exchange (ETDEWEB)

Within the framework of homogeneous models of the Universe, inflation provides the simplest explanation for the present cosmic isotropy, and a Bianchi type-IX (mixmaster) model is the least prejudiced guess we can make about the state of the Universe before the inflationary phase. However, a mixmaster model would not inflate unless either shear or the radiation energy density are large enough. Particle creation enhances the radiation energy density and therefore enlarges the set of inflating initial conditions for the Universe.

1991-11-15

481

Optical spectroscopy of uranium monochalcogenides and monopnictides  

International Nuclear Information System (INIS)

The optical properties of uranium monochalcogenides and monopnictides are discussed in terms of their electronic structure. A comparison is made with corresponding rare earth compounds. It is shown that there are close similarities to mixed valence CeN. the results support the occurrence of a dip in the density of d states near Esub(F), where the f density of states has its maximum. Empirical energy level schemes are derived which are found to agree with the existing information from XPS measurements and recent theories. (orig.).

1980-12-01

482

Optical measurement of electron bunching in vacuum  

International Nuclear Information System (INIS)

We report the homodyne detection of phase modulation sidebands induced on a laser beam by a coherently bunched electron beam. This provides a sensitive and nonperturbing measurement of complex Fourier time series components of the electron density. A proof-of-principle measurement of the microwave frequency component of electron density in a crossed-field device, which agrees well with a calculation of the same quantity, is reported.

483

Nonisothermal Atmospheric Dispersion Model for a Gaseous Pollutant of Any Density in the Presence of Orographic Nonuniformities Modele de Dispersion Atmospherique Non-Isotherme d'UN Pollutant Gazeux de Densite Quelconque en Presence de Non-Uniformites Orographiques.  

Science.gov (United States)

A mathematical model describing the behavior of a gas of any density released into a turbulent atmosphere was developed. A numerical treatment was established for two dimensional flow. An understanding of the effects of accidental or continuous release wa...

1981-01-01

484

Nonformity of the electron density in amorphous silicon films  

Energy Technology Data Exchange (ETDEWEB)

The authors study the nonuniformity of a-Si:H films obtained by the method of vacuum condensation, with the help of x-ray small-angle scattering (SLS) and transmission electron microscopy. Films of hydrogenated amorphous silicon are greatest interest, because the electronic properties of this material can be controlled by doping. As a result of the compensation of the ruptured bonds, and possibly, effects of melting, the properties of such films are analogous to those of singlecrystalline silicon. XLS enables a quantitative determination of the prameters of the regions of low electron density (RLD) in such objects.

1985-12-01

485

Instantaneous energy density as a feature for gear fault detection  

Science.gov (United States)

In this work, energy-based features for gear fault diagnosis and prediction are proposed. The instantaneous energy density is shown to obtain high values when defected teeth are engaged. Three methods are compared in terms of sensitivity, reliability and computation effectiveness. The Wigner Ville distribution is contrasted to the wavelet transform and the newly proposed empirical mode decomposition scheme. It is shown that all three methods are capable of a reliable prediction. An empirical law, which relates the energy content to the crack magnitude is established.

2006-07-01

486

Immunohistochemical localization of low density lipoprotein receptor-related protein 1 and ?2-Macroglobulin in retinal and choroidal tissue of proliferative retinopathies  

UK PubMed Central (United Kingdom)

The immunolocalization of the low density lipoprotein receptor-related protein 1 (LRP1) and its ligand alpha 2-Macroglobulin (α2M) was examined in tissues from human donor...Full Text Available

2010-08-01

487

Evaluation of adhesive plasters by radionuclide X-ray fluorescence analysis  

International Nuclear Information System (INIS)

A radiometric method was elaborated for surface density determinations of the adhesive layer of plasters by radionuclide X-ray fluorescence using the 17.47 keV bremsstrahlung of "1"4"7Pm/Mo. The bremsstrahlung line excites the 8.63 keV characteristic K#alpha# line of Zn contained in the adhesive layer of the plaster as a filling material in the form of ZnO. In homogeneous adhesive layers the Zn content is proportional to surface density. (author).

1976-01-01

488

Energy density ten times as high; Energy engineering: Zinc/air battery systems on trial. Dichte verzehnfacht; Energietechnik: Zink-Luft-Batteriesystem im Test  

Energy Technology Data Exchange (ETDEWEB)

Prior to an industrial-scale test of zinc/air batteries at Greven, the TUeV Bayern-Sachsen carried out preliminary tests on behalf of the Deutsche Bundespost. The results were quite promising: The energy density of the new battery is ten times as high as that of conventional lead batteries, and the battery-powered test vehicle had a range of up to 300 km. (orig.)

1994-01-01

489

Electrospun carbon fiber mat with layered architecture for anode in microbial fuel cells  

British Library Electronic Table of Contents (United Kingdom)

Layered carbon fiber mats have been prepared by layer-by-layer (LBL) electrospinning of polyacrylonitrile onto thin natural cellulose paper and subsequent carbonization. The layered carbon fiber mat has been proved to be a promising microbial fuel cell anode for high density layered biofilm propagation and high bioelectrocatalytic anodic current density.

2011-01-01

490

Effect of heparin-induced lipolysis on the distribution of apolipoprotein e among lipoprotein subclasses. Studies with patients deficient in hepatic triglyceride lipase and lipoprotein lipase.  

UK PubMed Central (United Kingdom)

In normal subjects, apolipoprotein E (apo E) is present on very low density lipoproteins (VLDL) (fraction I) and on particles of a size intermediate between VLDL and low density lipoproteins (LDL) (fraction...Full Text Available

1985-02-01

491

Effect of areal power density and relative humidity on corrosion resistant container performance  

Energy Technology Data Exchange (ETDEWEB)

The impact of the rewetting process on the performance of waste containers at the Yucca Mountain repository is analyzed. This paper explores the impact of the temperature-humidity relationships on pitting corrosion failure of stainless steel containers for different areal power densities (APDs)in the repository. It compares the likely performance of containers in a repository with a low APD, 55 Kw/acre, and a high APD, 110 kW/acre.

1994-10-01

492

Dependence of differential cross sections of 100-150 MeV #alpha#-particle elastic scattering on "4"0Ca on character of nucleon density distribution in nucleus  

International Nuclear Information System (INIS)

A theoretical model is proposed for analyzing elastic scattering of 100-150 MeV #alpha#-particles on intermediate mass nuclei. It is shown that, within the scope of this model accounting for inhomogeneous target-nucleus density, an anomalous growth of differential cross section of elastic scattering in the region of average angles can be explained.

493

Densities and molar volumes of molten alkaline earth bromide - alkali bromide salt mixtures  

International Nuclear Information System (INIS)

The temperature and concentration dependence of the densities of binary CaBr_2-(Li, Na, K, Rb, Cs)Br, NaBr-(Sr, Ba)Br_2 and KBr-SrBr_2 mixtures have been measured using the method of hydrostatic weighing. With exception of the systems LiBr-CaBr_2 and NaBr-(Sr, Ba)Br_2 the calculated molar excess volumes are positiv in the investigated mixtures. (author).

1980-01-01

494

Cumulative kaon production by 10 GeV protons  

International Nuclear Information System (INIS)

The K"+- and K"-meson cumulative production cross sections are measured at 119"0 in the laboratory system on nuclei Be, Al, Cu and Ta bombarded by 10 GeV protons. Spectra of the K"-mesons consisting of only sea quarks show universal features characteristic of the spectra of cumulative particles, which contain valence quarks. Evidence is obtained for the fact that the energy density in a flucton can exceed the mean nuclear density by an order of magnitude.

495

Cross Entropy Approximation of Structured Covariance Matrices  

CERN Document Server

We apply two variations of the principle of Minimum Cross Entropy (the Kullback information measure) to fit parameterized probability density models to observed data densities. For an array beamforming problem with P incident narrowband point sources, N > P sensors, and colored noise, both approaches yield eigenvector fitting methods similar to that of the MUSIC algorithm[1]. Furthermore, the corresponding cross-entropies are related to the MDL model order selection criterion[2].

2006-01-01

496

Computer tomography used in tumour diagnosis in children  

Energy Technology Data Exchange (ETDEWEB)

Computer tomography used in the diagnosis of tumours is described in the light of particularly great diagnostic difficulties in children. Computer tomography was applied in 12 cases. A high diagnostic value of this method was demonstrated, which makes possible a more accurate diagnosis of the position of the tumour, its size, and expanding tendency. The possibility of estimating healthy tissues and organs, and those with pathological changes on the basis of differences in their density with a detection threshold at 0.5% density difference facilitates not infrequently preoperative diagnosis raising the value of the method.

1981-01-01

497

CRC handbook of physical properties of rocks. Volume III  

Energy Technology Data Exchange (ETDEWEB)

This book presents topics on: Density of rocks and minerals, includes histograms of density ranges; elastic constants of minerals, elastic moduli, thermal properties; inelastic properties, strength and rheology for rocks and minerals, rock mechanics and friction, and stress-strain relations; radioactivity, decay constants and heat production of isotope systems in geology; seismic attenuation, in rocks, minerals, and the earth, with application to oil exploration and terrestrial studies; and index.

1984-01-01

498

Battery using a metal particle bed electrode  

Energy Technology Data Exchange (ETDEWEB)

A zinc-air battery in a case including a zinc particle bed supported adjacent the current feeder and diaphragm on a porous support plate which holds the particles but passes electrolyte solution. Electrolyte is recycled through a conduit between the support plate and top of the bed by convective forces created by a density of differential caused by a higher concentration of high density discharge products in the interstices of the bed than in the electrolyte recycle conduit.

1991-01-01

499

Battery using a metal particle bed electrode  

Energy Technology Data Exchange (ETDEWEB)

A zinc-air battery in a case is described including a zinc particle bed supported adjacent the current feeder and diaphragm on a porous support plate which holds the particles but passes electrolyte solution. Electrolyte is recycled through a conduit between the support plate and top of the bed by convective forces created by a density of differential caused by a higher concentration of high density discharge products in the interstices of the bed than in the electrolyte recycle conduit. 7 figures.

1991-04-09