Delimiting Coefficient a from Internal Consistency and Unidimensionality
Sijtsma, Klaas
2015-01-01
I discuss the contribution by Davenport, Davison, Liou, & Love (2015) in which they relate reliability represented by coefficient a to formal definitions of internal consistency and unidimensionality, both proposed by Cronbach (1951). I argue that coefficient a is a lower bound to reliability and that concepts of internal consistency and…
Delimiting coefficient alpha from internal consistency and unidimensionality
Sijtsma, K.
2015-01-01
I discuss the contribution by Davenport, Davison, Liou, & Love (2015) in which they relate reliability represented by coefficient α to formal definitions of internal consistency and unidimensionality, both proposed by Cronbach (1951). I argue that coefficient α is a lower bound to reliability and
Ponterotto, Joseph G; Ruckdeschel, Daniel E
2007-12-01
The present article addresses issues in reliability assessment that are often neglected in psychological research such as acceptable levels of internal consistency for research purposes, factors affecting the magnitude of coefficient alpha (alpha), and considerations for interpreting alpha within the research context. A new reliability matrix anchored in classical test theory is introduced to help researchers judge adequacy of internal consistency coefficients with research measures. Guidelines and cautions in applying the matrix are provided.
Estimators of internal consistency in health research: the use of the alpha coefficient
Cascaes da Silva, Fraciele; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil.; Gonçalves, Elizandra; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil.; Valdivia Arancibia, Beatriz Angélica; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil; Graziele Bento, Salma; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil.; da Silva Castro, Thiago Luis; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil; Soleman Hernandez, Salma Stephany; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil; da Silva, Rudney; Centro de Ciencias de la Salud y del Deporte, Universidad del Estado de Santa Catarina, Santa Catarina, Brasil
2015-01-01
Academic production has increased in the area of health, increasingly demanding high quality in publications of great impact. One of the ways to consider quality is through methods that increase the consistency of data analysis, such as reliability which, depending on the type of data, can be evaluated by different coefficients, especially the alpha coefficient. Based on this, the present review systematically gathers scientific articles produced in the last five years, which in a methodologi...
Choice, internal consistency, and rationality
Aditi Bhattacharyya; Prasanta K. Pattanaik; Yongsheng Xu
2010-01-01
The classical theory of rational choice is built on several important internal consistency conditions. In recent years, the reasonableness of those internal consistency conditions has been questioned and criticized, and several responses to accommodate such criticisms have been proposed in the literature. This paper develops a general framework to accommodate the issues raised by the criticisms of classical rational choice theory, and examines the broad impact of these criticisms from both no...
Analysis of internal conversion coefficients
International Nuclear Information System (INIS)
Coursol, N.; Gorozhankin, V.M.; Yakushev, E.A.; Briancon, C.; Vylov, Ts.
2000-01-01
An extensive database has been assembled that contains the three most widely used sets of calculated internal conversion coefficients (ICC): [Hager R.S., Seltzer E.C., 1968. Internal conversion tables. K-, L-, M-shell Conversion coefficients for Z=30 to Z=103, Nucl. Data Tables A4, 1-237; Band I.M., Trzhaskovskaya M.B., 1978. Tables of gamma-ray internal conversion coefficients for the K-, L- and M-shells, 10≤Z≤104, Special Report of Leningrad Nuclear Physics Institute; Roesel F., Fries H.M., Alder K., Pauli H.C., 1978. Internal conversion coefficients for all atomic shells, At. Data Nucl. Data Tables 21, 91-289] and also includes new Dirac-Fock calculations [Band I.M. and Trzhaskovskaya M.B., 1993. Internal conversion coefficients for low-energy nuclear transitions, At. Data Nucl. Data Tables 55, 43-61]. This database is linked to a computer program to plot ICCs and their combinations (sums and ratios) as a function of Z and energy, as well as relative deviations of ICC or their combinations for any pair of tabulated data. Examples of these analyses are presented for the K-shell and total ICCs of the gamma-ray standards [Hansen H.H., 1985. Evaluation of K-shell and total internal conversion coefficients for some selected nuclear transitions, Eur. Appl. Res. Rept. Nucl. Sci. Tech. 11.6 (4) 777-816] and for the K-shell and total ICCs of high multipolarity transitions (total, K-, L-, M-shells of E3 and M3 and K-shell of M4). Experimental data sets are also compared with the theoretical values of these specific calculations
Internal Branding and Employee Brand Consistent Behaviours
DEFF Research Database (Denmark)
Mazzei, Alessandra; Ravazzani, Silvia
2017-01-01
constitutive processes. In particular, the paper places emphasis on the role and kinds of communication practices as a central part of the nonnormative and constitutive internal branding process. The paper also discusses an empirical study based on interviews with 32 Italian and American communication managers...... and 2 focus groups with Italian communication managers. Findings show that, in order to enhance employee brand consistent behaviours, the most effective communication practices are those characterised as enablement-oriented. Such a communication creates the organizational conditions adequate to sustain......Employee behaviours conveying brand values, named brand consistent behaviours, affect the overall brand evaluation. Internal branding literature highlights a knowledge gap in terms of communication practices intended to sustain such behaviours. This study contributes to the development of a non...
Graphical comparison of calculated internal conversion coefficients
International Nuclear Information System (INIS)
Ewbank, W.B.
1980-11-01
Calculated values of the coefficients of internal conversion of gamma rays in the K shell and L 1 , L 2 , L 3 subshells from published tabulations by Band and Trzhaskovskaya and by Roesel et al. at Data Nucl. Data Tables, 21, 92-514(1978) are compared with values obtained by computer interpolation among tabulated values of Hager and Seltzer Nucl. Data, A4, 1-235(1968). In some cases, agreement among the three calculations is remarkably good, and differences are generally less than 5%. In a few cases, there are differences as large as 20 to 50%, corresponding to the threshold effect described by Roesel et al. The Z-dependent resonance minimum described by Roesel et al. is also observed in the comparison of E1-E4 conversion in the L 1 subshell. In several cases (notably M1-M4 conversion in the K shell and L 1 subshell), the Band and Roesel calculations show dramatically different dependence on gamma energy and atomic number. For Z = 100, the Band calculation for E4 conversion in the L 3 subshell shows irregular behavior at energies below the K-shell binding energy. A few high-quality measurements of internal conversion coefficients (+-5%) would help greatly to establish a basis for choice among the theoretical calculations. 32 figures
Determination of absolute internal conversion coefficients using the SAGE spectrometer
Energy Technology Data Exchange (ETDEWEB)
Sorri, J., E-mail: juha.m.t.sorri@jyu.fi [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Greenlees, P.T.; Papadakis, P.; Konki, J. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Cox, D.M. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Department of Physics, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Auranen, K.; Partanen, J.; Sandzelius, M.; Pakarinen, J.; Rahkila, P.; Uusitalo, J. [University of Jyvaskyla, Department of Physics, P.O. Box 35, FI-40014 University of Jyvaskyla (Finland); Herzberg, R.-D. [Department of Physics, University of Liverpool, Oxford Street, Liverpool L69 7ZE (United Kingdom); Smallcombe, J.; Davies, P.J.; Barton, C.J.; Jenkins, D.G. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom)
2016-03-11
A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of {sup 154}Sm, {sup 152}Sm and {sup 166}Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine absolute internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the absolute internal conversion coefficients can be extracted using the methods described with a reasonable accuracy. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.
Determination of absolute internal conversion coefficients using the SAGE spectrometer
International Nuclear Information System (INIS)
Sorri, J.; Greenlees, P.T.; Papadakis, P.; Konki, J.; Cox, D.M.; Auranen, K.; Partanen, J.; Sandzelius, M.; Pakarinen, J.; Rahkila, P.; Uusitalo, J.; Herzberg, R.-D.; Smallcombe, J.; Davies, P.J.; Barton, C.J.; Jenkins, D.G.
2016-01-01
A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of "1"5"4Sm, "1"5"2Sm and "1"6"6Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine absolute internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the absolute internal conversion coefficients can be extracted using the methods described with a reasonable accuracy. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.
Davenport, Ernest C.; Davison, Mark L.; Liou, Pey-Yan; Love, Quintin U.
2015-01-01
This article uses definitions provided by Cronbach in his seminal paper for coefficient a to show the concepts of reliability, dimensionality, and internal consistency are distinct but interrelated. The article begins with a critique of the definition of reliability and then explores mathematical properties of Cronbach's a. Internal consistency…
Calculation of effective absorption coefficient for aerosols of internal mixture
International Nuclear Information System (INIS)
Xu Bo; Huang Yinbo; Fan Chengyu; Qiao Chunhong
2012-01-01
The effective absorption coefficient with time of strong absorbing aerosol made of carbon dusts and water of internal mixture is analyzed, and the influence of different wavelengths and radius ratios on it is discussed. The shorter the wavelength is, the larger the effective absorption coefficient is , and more quickly it increases during 1-100 μs, and the largest increase if 132.65% during 1-100 μs. Different ratios between inner and outer radius have large influence on the effective absorption coefficient. The larger the ratio is, the larger the effective absorption coefficient is, and more quickly it increases during 1-100 μs. The increase of the effective absorption coefficient during 1-100 μs is larger than that during 100-1000 μs, and the largest increase is 138.66% during 1-100 μs. (authors)
Remaining useful life prediction based on variation coefficient consistency test of a Wiener process
Directory of Open Access Journals (Sweden)
Juan LI
2018-01-01
Full Text Available High-cost equipment is often reused after maintenance, and whether the information before the maintenance can be used for the Remaining Useful Life (RUL prediction after the maintenance is directly determined by the consistency of the degradation pattern before and after the maintenance. Aiming at this problem, an RUL prediction method based on the consistency test of a Wiener process is proposed. Firstly, the parameters of the Wiener process estimated by Maximum Likelihood Estimation (MLE are proved to be biased, and a modified unbiased estimation method is proposed and verified by derivation and simulations. Then, the h statistic is constructed according to the reciprocal of the variation coefficient of the Wiener process, and the sampling distribution is derived. Meanwhile, a universal method for the consistency test is proposed based on the sampling distribution theorem, which is verified by simulation data and classical crack degradation data. Finally, based on the consistency test of the degradation model, a weighted fusion RUL prediction method is presented for the fuel pump of an airplane, and the validity of the presented method is verified by accurate computation results of real data, which provides a theoretical and practical guidance for engineers to predict the RUL of equipment after maintenance.
Problems is applying new internal dose coefficients to radiation control
Energy Technology Data Exchange (ETDEWEB)
Sato, Yuichi [Oarai Laboratory, Chiyoda Technol Corporation, Ibaraki (Japan)
1998-06-01
The author discussed problems concerning the conceivable influence in the radiation control and those newly developing when the new internal dose coefficients are applied in the law in the future. For the conceivable influence, the occupational and public exposure was discussed: In the former, the effective dose equivalent limit (at present, 50 mSv/y) was thought to be reduced and in the latter, the limit to be obscure although it might be more greatly influenced by the new coefficients. For newly developing problems, since the new biological model which is more realistic was introduced for calculation of the internal dose and made the calculation more complicated, use of computer is requisite. The effective dose of the internal exposure in the individual monitoring should be conveniently calculated as done at present even after application of the new coefficients. For calculation of the effective dose of the internal exposure, there are such problems as correction of the inhaled particle size and of the individual personal parameter. A model calculation of residual rate in the chest where the respiratory tract alone participated was presented as an example but for the whole body, more complicated functions were pointed out necessary. The concept was concluded to be incorporated in the law in a convenient and easy manner and a software for calculation of internal dose using the new coefficients was wanted. (K.H.)
How good are the internal conversion coefficients now?
International Nuclear Information System (INIS)
Raman, S.; Nestor, C.W. Jr.; Ichihara, A.; Trzhaskovskaya, M.B.
2002-01-01
To fully utilize experimental internal conversion coefficients, one needs a reliable calculation of theoretical values. We have assembled a set of 100 experimental conversion coefficients, 45 α K and 55 α T values, measured with an accuracy of better than 5%, and generated the corresponding theoretical values using two methods, relativistic Hartree-Fock-Slater (RHFS) and relativistic Dirac-Fock (DF). Extensive comparisons of the experimental values with the two sets of theoretical values show that the DF method is clearly superior to the RHFS method in the overall reproduction of the experimental internal conversion coefficients. We discuss in some detail the differences between various versions of these two theoretical approaches, with a view to understanding which of these differences are most critical to obtaining agreement with experiment
Construct validity and internal consistency in the Leisure Practices Scale (EPL) for adults.
Andrade, Rubian Diego; Schwartz, Gisele Maria; Tavares, Giselle Helena; Pelegrini, Andreia; Teixeira, Clarissa Stefani; Felden, Érico Pereira Gomes
2018-02-01
This study proposes and analyzes the construct validity and internal consistency of the Leisure Practices Scale (EPL). This survey seeks to identify the preferences and involvement in in different leisure practices in adults. The instrument was formed based on the cultural leisure content (artistic, manual, physical, sports, intellectual, social, tourist, virtual and contemplation/leisure). The validation process was conducted with: a) content analysis by leisure experts, who evaluated the instrument for clarity of language and practical relevance, which allowed the calculation of the content validity coefficient (CVC); b) reproducibility test-retest with 51 subjects to calculate the temporal variation coefficient; c) internal consistency analysis with 885 participants. The evaluation presented appropriate coefficients, both with respect to language clarity (CVCt = 0.883) and practical relevance (CVCt = 0.879). The reproducibility coefficients were moderate to excellent. The scale showed adequate internal consistency (0.72). The EPL has psychometric quality and acceptable values in its structure, and can be used to investigate adult involvement in leisure activities.
Self-consistent transport coefficients for average collective motion at moderately high temperatures
International Nuclear Information System (INIS)
Yamaji, Shuhei; Hofmann, H.; Samhammer, R.
1987-01-01
Linear response theory is applied to compute the coefficients for inertia, friction and local stiffness for slow, large scale nuclear collective motion. It is shown how these coefficients can be defined within a locally harmonic approximation. The latter allows to study the implications arising from a finite local collective frequency. It is only for temperatures around 2 MeV that the zero frequency limit becomes a fair approximation. Friction is found to have a marked temperature dependence. The numerical computations are performed on the basis of a two-center shell model, but allowing the particles and holes to become dressed through effects of the medium. The dependence of the transport coefficients on the parameters of these self-energies is studied. It is argued that the uncertainties are smaller than a factor of 2. (orig.)
Test research of consistency for amplitude calibration coefficients of pulsed electric field sensor
International Nuclear Information System (INIS)
Meng Cui; Guo Xiaoqiang; Chen Xiangyue; Nie Xin; Mao Congguang; Xiang Hui; Cheng Jianping
2007-01-01
The amplitude calibration of an electric field sensor is important in the measurement of electromagnetic pulse. In this paper, an arbitrary waveform generator (AWG) is used to generate multi-waveform electric field in the TEM cell and the dipole antenna pulsed electric field sensor is calibrated. In the frequency band of the sensor, the calibrated amplitude coefficients with different waveforms are identical. The coefficient derived from the TEM cell calibration system suits to the measurement of unknown electric field pulse within the frequency band. (authors)
Directory of Open Access Journals (Sweden)
V. S. Zarubin
2015-01-01
Full Text Available The rational use of composites as structural materials, while perceiving the thermal and mechanical loads, to a large extent determined by their thermoelastic properties. From the presented review of works devoted to the analysis of thermoelastic characteristics of composites, it follows that the problem of estimating these characteristics is important. Among the thermoelastic properties of composites occupies an important place its temperature coefficient of linear expansion.Along with fiber composites are widely used in the technique of dispersion hardening composites, in which the role of inclusions carry particles of high-strength and high-modulus materials, including nanostructured elements. Typically, the dispersed particles have similar dimensions in all directions, which allows the shape of the particles in the first approximation the ball.In an article for the composite with isotropic spherical inclusions of a plurality of different materials by the self-produced design formulas relating the temperature coefficient of linear expansion with volume concentration of inclusions and their thermoelastic characteristics, as well as the thermoelastic properties of the matrix of the composite. Feature of the method is the self-accountability thermomechanical interaction of a single inclusion or matrix particles with a homogeneous isotropic medium having the desired temperature coefficient of linear expansion. Averaging over the volume of the composite arising from such interaction perturbation strain and stress in the inclusions and the matrix particles and makes it possible to obtain such calculation formulas.For the validation of the results of calculations of the temperature coefficient of linear expansion of the composite of this type used two-sided estimates that are based on the dual variational formulation of linear thermoelasticity problem in an inhomogeneous solid containing two alternative functional (such as Lagrange and Castigliano
Lindgren, Margareta; Andersson, Inger S
2011-06-01
Valid and reliable instruments for measuring the quality of care are needed for evaluation and improvement of nursing care. Previously developed and evaluated instruments, the Karen-patient and the Karen-personnel based on Donabedian's Structure-Process-Outcome triad (S-P-O triad) had promising content validity, discriminative power and internal consistency. The objective of this study was to further develop the instruments with regard to construct validity and internal consistency. This prospective study was carried out in medical and surgical wards at a hospital in Sweden. A total of 95 patients and 120 personnel were included. The instruments were tested for construct validity by performing factor analyses in two steps and for internal consistency using Cronbach's alpha coefficient. The first confirmatory factor analyses, with a pre-determined three-factor solution did not load well according to the S-P-O triad, but the second exploratory factor analysis with a six-factor solution appeared to be more coherent and the distribution of variables seemed to be logical. The reliability, i.e. internal consistency, was good in both factor analyses. The Karen-patient and the Karen-personnel instruments have achieved acceptable levels of construct validity. The internal consistency of the instruments is good. This indicates that the instruments may be suitable to use in clinical practice for measuring the quality of nursing care.
Directory of Open Access Journals (Sweden)
R. P. Gerber
2013-03-01
Full Text Available Currently, the most successful predictive models for activity coefficients are those based on functional groups such as UNIFAC. In contrast, these models require a large amount of experimental data for the determination of their parameter matrix. A more recent alternative is the models based on COSMO, for which only a small set of universal parameters must be calibrated. In this work, a recalibrated COSMO-SAC model was compared with the UNIFAC (Do model employing experimental infinite dilution activity coefficient data for 2236 non-hydrogen-bonding binary mixtures at different temperatures. As expected, UNIFAC (Do presented better overall performance, with a mean absolute error of 0.12 ln-units against 0.22 for our COSMO-SAC implementation. However, in cases involving molecules with several functional groups or when functional groups appear in an unusual way, the deviation for UNIFAC was 0.44 as opposed to 0.20 for COSMO-SAC. These results show that COSMO-SAC provides more reliable predictions for multi-functional or more complex molecules, reaffirming its future prospects.
Simancas-Pallares, Miguel Angel; Fortich Mesa, Natalia; González Martínez, Farith Damián
To determine the internal consistency and content validity of the Maslach Burnout Inventory-Student Survey (MBI-SS) in dental students from Cartagena, Colombia. Scale validation study in 886 dental students from Cartagena, Colombia. Factor structure was determined through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Internal consistency was measured using the Cronbach's alpha coefficient. Analyses were performed using the Stata v.13.2 for Windows (Statacorp., USA) and Mplus v.7.31 for Windows (Muthén & Muthén, USA) software. Internal consistency was α=.806. The factor structure showed three that accounted for the 56.6% of the variance. CFA revealed: χ 2 =926.036; df=85; RMSEA=.106 (90%CI, .100-.112); CFI=.947; TLI=.934. The MBI showed an adequate internal consistency and a factor structure being consistent with the original proposed structure with a poor fit, which does not reflect adequate content validity in this sample. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
Internal conversion coefficients of high multipole transitions: Experiment and theories
International Nuclear Information System (INIS)
Gerl, J.; Vijay Sai, K.; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K.
2008-01-01
A compilation of the available experimental internal conversion coefficients (ICCs), α T , α K , α L , and ratios K/L and K/LM of high multipole (L > 2) transitions for a number of elements in the range 21 ≤ Z ≤ 94 is presented. Our listing of experimental data includes 194 data sets on 110 E3 transitions, 10 data sets on 6 E4 transitions, 11 data sets on 7 E5 transitions, 38 data sets on 21 M3 transitions, and 132 data sets on 68 M4 transitions. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer [R.S. Hager, E.C. Seltzer, Nucl. Data Tables A 4 (1968) 1], Rosel et al. [F. Roesel, H.M. Fries, K. Alder, H.C. Pauli, At. Data Nucl. Data Tables 21 (1978) 91], and BRICC. The relative percentage deviations (%Δ) have been calculated for each of the above theories and the averages (%Δ-bar) are estimated. The Band et al. [I.M. Band, M.B. Trzhaskovskaya, C.W. Nestor Jr., P.O. Tikkanen, S. Raman, At. Data Nucl. Data Tables 81 (2002) 1] tables, using the BRICC interpolation code, are seen to give theoretical ICCs closest to experimental values
International Nuclear Information System (INIS)
Deniz, V.C.
1980-01-01
The problem concerned with the correct definition of the homogenized diffusion coefficient of a lattice, and the concurrent problem of whether or not a homogenized diffusion equation can be formally set up, is studied by a space-energy-angle dependent treatment for a general lattice cell using an operator notation which applies to any eigen-problem. A new definition of the diffusion coefficient is given, which combines within itself the individual merits of the two definitions of Benoist. The relation between the new coefficient and the ''uncorrected'' Benoist coefficient is discussed by considering continuous-spectrum and multi-group diffusion equations. Other definitions existing in the literature are briefly discussed. It is concluded that a diffusion coefficient should represent only leakage effects. A comparison is made between the homogenization approach and the approach via eigen-coefficients, and brief indications are given of a possible scheme for the latter. (author)
International Nuclear Information System (INIS)
Deniz, V.C.
1978-01-01
The problem concerned with the correct definition of the homogenized diffusion coefficient of a lattice, and the concurrent problem of whether or not a homogenized diffusion equation can be formally set up, is studied by a space-energy angle dependent treatment for a general lattice cell; using an operator notation which applies to any eigen-problem. It is shown that the diffusion coefficient should represent only leakage effects. A new definition of the diffusion coefficient is given, which combines within itself the individual merits of each of the two definitions of Benoist, and reduces to the 'uncorrected' Benoist coefficient in certain cases. The conditions under which a homogenized diffusion equation can be obtained are discussed. A compatison is made between the approach via a diffusion equation and the approach via the eigen-coefficients of Deniz. Previously defined diffusion coefficients are discussed, and it is shown that the transformed eigen-coefficients proposed by Gelbard and by Larsen are unsuitable as diffusion coefficients, and that the cell-edge normalization of the Bonalumi coefficient is not physically justifiable. (author)
Internally consistent gamma ray burst time history phenomenology
International Nuclear Information System (INIS)
Cline, T.L.
1985-01-01
A phenomenology for gamma ray burst time histories is outlined. Order of their generally chaotic appearance is attempted, based on the speculation that any one burst event can be represented above 150 keV as a superposition of similarly shaped increases of varying intensity. The increases can generally overlap, however, confusing the picture, but a given event must at least exhibit its own limiting characteristic rise and decay times if the measurements are made with instruments having adequate temporal resolution. Most catalogued observations may be of doubtful or marginal utility to test this hypothesis, but some time histories from Helios-2, Pioneer Venus Orbiter and other instruments having one-to several-millisecond capabilities appear to provide consistency. Also, recent studies of temporally resolved Solar Maximum Mission burst energy spectra are entirely compatible with this picture. The phenomenology suggested here, if correct, may assist as an analytic tool for modelling of burst processes and possibly in the definition of burst source populations
Bootstrap embedding: An internally consistent fragment-based method
Energy Technology Data Exchange (ETDEWEB)
Welborn, Matthew; Tsuchimochi, Takashi; Van Voorhis, Troy [Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139 (United States)
2016-08-21
Strong correlation poses a difficult problem for electronic structure theory, with computational cost scaling quickly with system size. Fragment embedding is an attractive approach to this problem. By dividing a large complicated system into smaller manageable fragments “embedded” in an approximate description of the rest of the system, we can hope to ameliorate the steep cost of correlated calculations. While appealing, these methods often converge slowly with fragment size because of small errors at the boundary between fragment and bath. We describe a new electronic embedding method, dubbed “Bootstrap Embedding,” a self-consistent wavefunction-in-wavefunction embedding theory that uses overlapping fragments to improve the description of fragment edges. We apply this method to the one dimensional Hubbard model and a translationally asymmetric variant, and find that it performs very well for energies and populations. We find Bootstrap Embedding converges rapidly with embedded fragment size, overcoming the surface-area-to-volume-ratio error typical of many embedding methods. We anticipate that this method may lead to a low-scaling, high accuracy treatment of electron correlation in large molecular systems.
Campo-Arias, Adalberto; Oviedo, Heidi Celina; Díaz, Carmen Elena; Cogollo, Zuleima
2006-12-01
This study evaluated the internal consistency of a Spanish version of the short form of the Francis Scale of Attitude Toward Christianity based on responses of 405 Colombian adolescent students ages 13 to 17 years. This translated short-form version of the scale had an internal consistency of .80. This estimate indicates suitable internal consistency reliability for research use in this population.
Directory of Open Access Journals (Sweden)
Luisa Matilde Salamanca-Duque
2014-09-01
Full Text Available Introduction: ADHD is one of the most common diagnoses in child psychiatry, its early diagnosis is of great importance for intervention at family, school and social environment. Based on the International Classification of Functioning, Disability and Health (ICF, a questionnaire was designed to assess activity limitations and participation restrictions in children with ADHD. The questionnaire was called “CLARP-ADHD Parent and Teacher Version”. Objective: To determine the degree of internal consistency of the CLARP-ADHD questionnaire, and its concurrent validity with the “Strengths and Difficulties Questionnaire SDQ parent and teacher version”. Material and Methods: A sample of 203 children aged 6 to 12 with ADHD, currently attending school in five Colombian cities. The questionnaires were applied to parents and teachers. The internal consistency analysis was performed through Cronbach coefficient and concurrent validity using the Spearman correlation coefficient utilizing multiple and unique predictors through multiple linear regression as well as simple regression models. Results: A high internal consistency was found for global questionnaires for each of its domains. The CLARP-ADHD for parents gave as result an internal consistency of 0.83, and the CLARP-ADHD for teachers one of 0.93. Concurrent validity was found between the CLARP-ADHD and the SDQ Parent and Teacher version; also, concurrence between the CLARPADHD for Teachers and the SDQ Teachers was found, as well as between CLARP ADHD for Parents and CLARP ADHD Teachers, given by p values of p < 0.001.
International Nuclear Information System (INIS)
Boyarskij, S.V.
1986-01-01
Experimental results are presented for internal friction and linear expansion coefficient at zirconium and cobalt in the temperature range from 440 K to the point of the phase transition of the first kind (1138 K for Zr and 706 for Co). Anomalous changes of the internal friction and linear expansion coefficient in the phase transition region are found. Theoretical considerations are given to explain the sharp decrease of the internal friction as temperature approaches the phase transition point
Effect of the refraction factor of a plastic fiber shell on the internal reflection coefficient
International Nuclear Information System (INIS)
Pkrksypkin, A.I.; Ponomarev, L.I.
1992-01-01
Results of pilot studies of the effect of refraction factor of plastic fiber shell on the coefficient of light internal reflection in the fiber are presented. It is pointed, that the shell does not absorb the light, but effects the surface layer of the fiber centre so, that dependence of the coefficient of internal reflection on refraction factor of the shell may be described using Fresnel formulae. It is shown, that coefficient of internal reflection decreases with the increase of refraction factor. Technique to determine volume length of scintillation light absorption in the fiber is suggested
Campo-Arias, Adalberto; Oviedo, Heidi Celina; Cogollo, Zuleima
2009-04-01
The short form of the Francis Scale of Attitude Toward Christianity (L. J. Francis, 1992) is a 7-item Likert-type scale that shows high homogeneity among adolescents. The psychometric performance of a shorter version of this scale has not been explored. The authors aimed to determine the internal consistency of a 5-item form of the Francis Scale of Attitude Toward Christianity among 405 students from a school in Cartagena, Colombia. The authors computed the Cronbach's alpha coefficient for the 5 items with a greater corrected item-total punctuation correlation. The version without Items 2 and 7 showed internal consistency of .87. The 5-item version of the Francis Scale of Attitude Toward Christianity exhibited higher internal consistency than did the 7-item version. Future researchers should corroborate this finding.
Absorbed Internal Dose Conversion Coefficients for Domestic Reference Animals and Plant
Energy Technology Data Exchange (ETDEWEB)
Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Choi, Yong Ho [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2010-02-15
This paper describes the methodology of calculating the internal dose conversion coefficient in order to assess the radiological impact on non-human species. This paper also presents the internal dose conversion coefficients of 25 radionuclides ({sup 3}H, {sup 7}Be, {sup 14}C, {sup 40}K, {sup 51}Cr, {sup 54}Mn, {sup 59}Fe, {sup 58}Co, {sup 60}Co, {sup 65}Zn, {sup 90}Sr, '9{sup 5}Zr, {sup 95}Nb, {sup 99}Tc, {sup 106}Ru, {sup 129}I, {sup 131}I, {sup 136}Cs, {sup 137}Cs, {sup 140}Ba, {sup 140}La, {sup 144}Ce, {sup 238}U, {sup 239}Pu, {sup 240}Pu) for domestic seven reference animals (roe deer, rat, frog, snake, Chinese minnow, bee, and earthworm) and one reference plant (pine tree). The uniform isotropic model was applied in order to calculate the internal dose conversion coefficients. The calculated internal dose conversion coefficient (muGyd{sup -1} per Bqkg{sup -1}) ranged from 10{sup -6} to 10{sup -2} according to the type of radionuclides and organisms studied. It turns out that the internal does conversion coefficient was higher for alpha radionuclides, such as {sup 238}U, {sup 239}Pu, and {sup 240}Pu, and for large organisms, such as roe deer and pine tree. The internal dose conversion coefficients of {sup 239}Pu, {sup 240}Pu, {sup 238}U, {sup 14}C, {sup 3}H and {sup 99}Tc were independent of the organism
Basiuk, V.; Huynh, P.; Merle, A.; Nowak, S.; Sauter, O.; Contributors, JET; the EUROfusion-IM Team
2017-12-01
The neoclassical tearing modes (NTM) increase the effective heat and particle radial transport inside the plasma, leading to a flattening of the electron and ion temperature and density profiles at a given location depending on the safety factor q rational surface (Hegna and Callen 1997 Phys. Plasmas 4 2940). In burning plasma such as in ITER, this NTM-induced increased transport could reduce significantly the fusion performance and even lead to a disruption. Validating models describing the NTM-induced transport in present experiment is thus important to help quantifying this effect on future devices. In this work, we apply an NTM model to an integrated simulation of current, heat and particle transport on JET discharges using the European transport simulator. In this model, the heat and particle radial transport coefficients are modified by a Gaussian function locally centered at the NTM position and characterized by a full width proportional to the island size through a constant parameter adapted to obtain the best simulations of experimental profiles. In the simulation, the NTM model is turned on at the same time as the mode is triggered in the experiment. The island evolution is itself determined by the modified Rutherford equation, using self-consistent plasma parameters determined by the transport evolution. The achieved simulation reproduces the experimental measurements within the error bars, before and during the NTM. A small discrepancy is observed on the radial location of the island due to a shift of the position of the computed q = 3/2 surface compared to the experimental one. To explain such small shift (up to about 12% with respect to the position observed from the experimental electron temperature profiles), sensitivity studies of the NTM location as a function of the initialization parameters are presented. First results validate both the transport model and the transport modification calculated by the NTM model.
On the internal consistency of the term structure of forecasts of housing starts
DEFF Research Database (Denmark)
Pierdzioch, C.; Rulke, J. C.; Stadtmann, G.
2013-01-01
We use the term structure of forecasts of housing starts to test for rationality of forecasts. Our test is based on the idea that short-term and long-term forecasts should be internally consistent. We test the internal consistency of forecasts using data for Australia, Canada, Japan and the United...
International Nuclear Information System (INIS)
Attallah, F.; Chemin, J.F.; Scheurer, J.N.; Karpeshin, F.; Harston, M.
1997-01-01
We have established a general relation for the expression of the internal conversion of an M 1 transition a 1s electronic state to an empty ns electronic bound state. Under the hypothesis that the density of the electron level ρ n satisfies the condition ρ n Γ >> 1 (where Γ is the total width of the excited atomic state) a calculation in the first order gives a relation for the internal conversion coefficient.This relation shows that the internal conversion coefficient takes a resonant character when the nuclear energy transition is smaller than the binding energy of the 1s electron. An application of this relation to an M 1 transition in the case of the ion 125 T e with a charge state Q = 45 and an 1s electron binding energy E B 45 = 35.581 KeV gives the value for the internal conversion coefficient R = 5.7
Peng, Dong-qing; Zhu, Li-li; Li, Zhi-fang; Li, Hui
2017-09-01
Absorption coefficient of biological tissue is an important parameter in biomedicine, but its determination remains a challenge. In this paper, we propose a method using focusing photoacoustic imaging technique and internal light irradiation of cylindrical diffusing fiber (CDF) to quantify the target optical absorption coefficient. Absorption coefficients for ink absorbers are firstly determined through photoacoustic and spectrophotometric measurements at the same excitation, which demonstrates the feasibility of this method. Also, the optical absorption coefficients of ink absorbers with several concentrations are measured. Finally, the two-dimensional scanning photoacoustic image is obtained. Optical absorption coefficient measurement and simultaneous photoacoustic imaging of absorber non-invasively are the typical characteristics of the method. This method can play a significant role for non-invasive determination of blood oxygen saturation, the absorption-based imaging and therapy.
Systematic errors in the tables of theoretical total internal conversion coefficients
International Nuclear Information System (INIS)
Dragoun, O.; Rysavy, M.
1992-01-01
Some of the total internal conversion coefficients presented in widely used tables of Rosel et al (1978 Atom. Data Nucl. Data Tables 21, 291) were found to be erroneous. The errors appear for some low transition energies, all multipolarities, and probably for all elements. The origin of the errors is explained. The subshell conversion coefficients of Rosel et al, where available, agree with our calculations. to within a few percent. (author)
International Nuclear Information System (INIS)
Arthur, R.C.
2001-11-01
This report addresses the concept of internal consistency and its relevance to the reliability of thermodynamic databases used in repository safety assessments. In addition to being internally consistent, a reliable database should be accurate over a range of relevant temperatures and pressures, complete in the sense that all important aqueous species, gases and solid phases are represented, and traceable to original experimental results. No single definition of internal consistency need to be universally accepted as the most appropriate under all conditions, however. As a result, two databases that are each internally consistent may be inconsistent with respect to each other, and a database derived from two or more such databases must itself be internally inconsistent. The consequences of alternative definitions that are reasonably attributable to the concept of internal consistency can be illustrated with reference to the thermodynamic database supporting SKB's recent SR 97 safety assessment. This database is internally inconsistent because it includes equilibrium constants calculated over a range of temperatures: using conflicting reference values for some solids, gases and aqueous species that are common to two internally consistent databases (the OECD/NEA database for radioelements and SUPCRT databases for non-radioactive elements) that serve as source databases for the SR 97 TDB, using different definitions in these source databases of standard states for condensed phases and aqueous species, based on different mathematical expressions used in these source databases representing the temperature dependence of the heat capacity, and based on different chemical models adopted in these source databases for the aqueous phase. The importance of such inconsistencies must be considered in relation to the other database reliability criteria noted above, however. Thus, accepting a certain level of internal inconsistency in a database it is probably preferable to use a
Energy Technology Data Exchange (ETDEWEB)
Arthur, R.C. [Monitor Scientific, LLC, Denver, CO (United States)
2001-11-01
This report addresses the concept of internal consistency and its relevance to the reliability of thermodynamic databases used in repository safety assessments. In addition to being internally consistent, a reliable database should be accurate over a range of relevant temperatures and pressures, complete in the sense that all important aqueous species, gases and solid phases are represented, and traceable to original experimental results. No single definition of internal consistency need to be universally accepted as the most appropriate under all conditions, however. As a result, two databases that are each internally consistent may be inconsistent with respect to each other, and a database derived from two or more such databases must itself be internally inconsistent. The consequences of alternative definitions that are reasonably attributable to the concept of internal consistency can be illustrated with reference to the thermodynamic database supporting SKB's recent SR 97 safety assessment. This database is internally inconsistent because it includes equilibrium constants calculated over a range of temperatures: using conflicting reference values for some solids, gases and aqueous species that are common to two internally consistent databases (the OECD/NEA database for radioelements and SUPCRT databases for non-radioactive elements) that serve as source databases for the SR 97 TDB, using different definitions in these source databases of standard states for condensed phases and aqueous species, based on different mathematical expressions used in these source databases representing the temperature dependence of the heat capacity, and based on different chemical models adopted in these source databases for the aqueous phase. The importance of such inconsistencies must be considered in relation to the other database reliability criteria noted above, however. Thus, accepting a certain level of internal inconsistency in a database it is probably preferable to
International Nuclear Information System (INIS)
Linjun, Xie; Guohong, Xue; Ming, Zhang
2016-01-01
Graphical abstract: HDS stress coefficient test apparatus. - Highlights: • This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. • The mathematical relation between the load and the strain is obtained about the HDS, and the mathematical model of the stress coefficient and the friction coefficient is established. So, a set of test apparatuses for obtaining the stress coefficient is designed according to the model scaling criterion and the friction coefficient of the K1000 HDS is calculated to be 0.336 through the obtained stress coefficient. • The relation curve between the theoretical load and the friction coefficient is obtained through analysis and indicates that the change of the friction coefficient f would influence the pretightening load under the condition of designed stress. The necessary pretightening load in the design process is calculated to be 5469 kN according to the obtained friction coefficient. Therefore, the friction coefficient and the pretightening load under the design conditions can provide accurate pretightening data for the analysis and design of the reactor HDS according to the operations. - Abstract: This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. By carrying out tests and researches through a stress testing technique, P–σ curves in loading and unloading processes of the HDS are obtained and the stress coefficient k f of the HDS is obtained. So, the
Energy Technology Data Exchange (ETDEWEB)
Linjun, Xie, E-mail: linjunx@zjut.edu.cn [College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014 (China); Guohong, Xue; Ming, Zhang [Shanghai Nuclear Engineering Research & Design Institute, Shanghai 200233 (China)
2016-08-01
Graphical abstract: HDS stress coefficient test apparatus. - Highlights: • This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. • The mathematical relation between the load and the strain is obtained about the HDS, and the mathematical model of the stress coefficient and the friction coefficient is established. So, a set of test apparatuses for obtaining the stress coefficient is designed according to the model scaling criterion and the friction coefficient of the K1000 HDS is calculated to be 0.336 through the obtained stress coefficient. • The relation curve between the theoretical load and the friction coefficient is obtained through analysis and indicates that the change of the friction coefficient f would influence the pretightening load under the condition of designed stress. The necessary pretightening load in the design process is calculated to be 5469 kN according to the obtained friction coefficient. Therefore, the friction coefficient and the pretightening load under the design conditions can provide accurate pretightening data for the analysis and design of the reactor HDS according to the operations. - Abstract: This paper performs mathematic deduction to the physical model of Hold Down Spring (HDS), establishes a mathematic model of axial load P and stress, stress coefficient and friction coefficient and designs a set of test apparatuses for simulating the pretightening process of the HDS for the first time according to a model similarity criterion. By carrying out tests and researches through a stress testing technique, P–σ curves in loading and unloading processes of the HDS are obtained and the stress coefficient k{sub f} of the HDS is obtained. So, the
Controlling the Internal Heat Transfer Coefficient by the Characteristics of External Flows
Zhuromskii, V. M.
2018-01-01
The engineering-physical fundamentals of substance synthesis in a boiling apparatus are presented. We have modeled a system of automatic stabilization of the maximum internal heat transfer coefficient in such an apparatus by the characteristics of external flows on the basis of adaptive seeking algorithms. The results of operation of the system in the shop are presented.
A diagnostic test for apraxia in stroke patients: internal consistency and diagnostic value.
Heugten, C.M. van; Dekker, J.; Deelman, B.G.; Stehmann-Saris, F.C.; Kinebanian, A.
1999-01-01
The internal consistency and the diagnostic value of a test for apraxia in patients having had a stroke are presented. Results indicate that the items of the test form a strong and consistent scale: Cronbach's alpha as well as the results of a Mokken scale analysis present good reliability and good
Hajcak, Greg; Meyer, Alexandria; Kotov, Roman
2017-08-01
In the clinical neuroscience literature, between-subjects differences in neural activity are presumed to reflect reliable measures-even though the psychometric properties of neural measures are almost never reported. The current article focuses on the critical importance of assessing and reporting internal consistency reliability-the homogeneity of "items" that comprise a neural "score." We demonstrate how variability in the internal consistency of neural measures limits between-subjects (i.e., individual differences) effects. To this end, we utilize error-related brain activity (i.e., the error-related negativity or ERN) in both healthy and generalized anxiety disorder (GAD) participants to demonstrate options for psychometric analyses of neural measures; we examine between-groups differences in internal consistency, between-groups effect sizes, and between-groups discriminability (i.e., ROC analyses)-all as a function of increasing items (i.e., number of trials). Overall, internal consistency should be used to inform experimental design and the choice of neural measures in individual differences research. The internal consistency of neural measures is necessary for interpreting results and guiding progress in clinical neuroscience-and should be routinely reported in all individual differences studies. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Ebel, B.A.; Mirus, B.B.; Heppner, C.S.; VanderKwaak, J.E.; Loague, K.
2009-01-01
Distributed hydrologic models capable of simulating fully-coupled surface water and groundwater flow are increasingly used to examine problems in the hydrologic sciences. Several techniques are currently available to couple the surface and subsurface; the two most frequently employed approaches are first-order exchange coefficients (a.k.a., the surface conductance method) and enforced continuity of pressure and flux at the surface-subsurface boundary condition. The effort reported here examines the parameter sensitivity of simulated hydrologic response for the first-order exchange coefficients at a well-characterized field site using the fully coupled Integrated Hydrology Model (InHM). This investigation demonstrates that the first-order exchange coefficients can be selected such that the simulated hydrologic response is insensitive to the parameter choice, while simulation time is considerably reduced. Alternatively, the ability to choose a first-order exchange coefficient that intentionally decouples the surface and subsurface facilitates concept-development simulations to examine real-world situations where the surface-subsurface exchange is impaired. While the parameters comprising the first-order exchange coefficient cannot be directly estimated or measured, the insensitivity of the simulated flow system to these parameters (when chosen appropriately) combined with the ability to mimic actual physical processes suggests that the first-order exchange coefficient approach can be consistent with a physics-based framework. Copyright ?? 2009 John Wiley & Sons, Ltd.
Bortoluzzi, Marcelo Carlos; Martins, Luciana Dorochenko; Takahashi, André; Ribeiro, Bianca; Martins, Ligiane; Pinto, Marcia Helena Baldani
2018-01-01
The scope of this study was to develop and validate a questionnaire (QCirDental) to measure the impacts associated with dental extraction surgery. The QCirDental questionnaire was developed in two steps; (1) question and item generation and selection, and (2) pretest of the questionnaire with evaluation of the its measurement properties (internal consistency and responsiveness). The sample was composed of 123 patients. None of the patients had any difficulty in understanding the QCirDental. The instrument was found to have excellent internal consistency with Cronbach's alpha reliability coefficient of 0.83. The principal component analysis (Kaiser-Meyer-Olkin Measure of Sampling Adequacy 0,72 and Bartlett's Test of Sphericity with p < 0.001) showed six (6) dimensions explaining 67.5% of the variance. The QCirDental presented excellent internal consistency, being a questionnaire that is easy to read and understand with adequate semantic and content validity. More than 80% of the patients who underwent dental extraction reported some degree of discomfort within the perioperative period which highlights the necessity to assess the quality of care and impacts of dental extraction surgery.
Consistent adoption of the International System of Units (SI) in nuclear science and technology
Energy Technology Data Exchange (ETDEWEB)
Klumpar, J; Kovar, Z [Ceskoslovenska Akademie Ved, Prague. Laborator Radiologicke Dozimetrie; Sacha, J [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Fyzikalny Ustav
1975-11-01
The principles are stressed behind a consistent introduction of the International System of Units (SI) in Czechoslovakia complying with the latest edition of the Czechoslovak Standard CSN 01 1300 on the prescribed system of national and international units. The use of special and auxiliary units in nuclear physics and technology is discussed, particular attention being devoted to the units of activity and to the time units applied in radiology. Conversion graph and tables are annexed.
The internal consistency of the standard gamble: tests after adjusting for prospect theory.
Oliver, Adam
2003-07-01
This article reports a study that tests whether the internal consistency of the standard gamble can be improved upon by incorporating loss weighting and probability transformation parameters in the standard gamble valuation procedure. Five alternatives to the standard EU formulation are considered: (1) probability transformation within an EU framework; and, within a prospect theory framework, (2) loss weighting and full probability transformation, (3) no loss weighting and full probability transformation, (4) loss weighting and no probability transformation, and (5) loss weighting and partial probability transformation. Of the five alternatives, only the prospect theory formulation with loss weighting and no probability transformation offers an improvement in internal consistency over the standard EU valuation procedure.
Directory of Open Access Journals (Sweden)
Juliana Burges Sbicigo
2010-12-01
Full Text Available O objetivo deste estudo foi investigar as propriedades psicométricas da Escala de Autoestima de Rosenberg (EAR para adolescentes. Participaram 4.757 adolescentes, com idades entre 14 e 18 anos (M=15,77; DP=1,22, de nove cidades brasileiras. Os participantes responderam a uma versão da EAR adaptada para o Brasil. A análise fatorial exploratória apontou uma estrutura bidimensional, com 51.4% da variância explicada, que foi sustentada pela análise fatorial confirmatória. As análises de consistência interna realizadas por meio do coeficiente alfa de Cronbach, confiabilidade composta e variância extraída indicaram bons valores de fidedignidade. Diferenças nos escores de autoestima em função do sexo e da idade não foram encontradas. Conclui-se que a EAR apresenta qualidades psicométricas satisfatórias, mostrando-se um instrumento confiável para medir autoestima em adolescentes brasileiros.The aim of this study was to investigate the psychometrics properties of the Rosenberg Self-Esteem Scale (RSS for adolescents. The sample was composed of 4.757 adolescents, with ages between 14 and 18 years old (M=15.77; SD=1.22 in nine Brazilian cities. Participants responded to an adapted version of the RSS for Brazil. Exploratory factorial analysis showed a bidimensional structure, with 51.4% of explained variance. This result was supported by confirmatory factor analysis. The internal consistency analysis by Cronbach alpha coefficient, composite reliability and extracted variance indicated good reliability. Differences in self-esteem for gender and age were not found. These findings show that RSS has satisfactory psychometric qualities and it's a reliable instrument to assess self-esteem in Brazilian adolescents.
International Nuclear Information System (INIS)
Gomez Parada, I.; Rojo, A.M.; Sanguineti, R.
1995-01-01
ICRP publication 60 introduces new biological information related to the detriment associated with radiation exposures. The International Commission on Radiological Protection has also issued, in publications 57, 67 y 69, new biokinetic models for selected radionuclides since the issue of publication 30. In publication 66 the new human respiratory tract model for radiological protection is described. The aim of the present paper is to compare values of dose coefficients for workers calculated using the new tissue weighting factors, biokinetic models and lung model with those given in publication 30.The software package LUPED 1.1 was used to calculate dose coefficients for inhalation and ingestion. When possible, some changes in the biokinetic models were made trying to incorporate new parameters. The following radionuclides were analysed: 60 Co, 90 Sr, 99m Tc, 131 I, 137 Cs, 239 Pu y 241 Am. Most of the inhalation dose coefficients calculated with the new assumptions are within a factor of three of those calculated using the ICRP 30 lung and biokinetic models. Generally, the inhalation dose coefficients calculated with the new respiratory tract model and assuming a 5μm AMAD are lower than those calculated using the ICRP 30 model and parameters. The inhalation dose coefficients are generally within 10-90 % of the corresponding Publication 61 values, the difference tending to increase for relative insoluble compounds. (author). 10 refs., 4 tabs
Rossinskyi, Volodymyr
2018-02-01
The biological wastewater treatment technologies in anoxic and aerobic bioreactors with recycle of sludge mixture are used for the effective removal of organic compounds from wastewater. The change rate of sludge mixture recirculation between bioreactors leads to a change and redistribution of concentrations of organic compounds in sludge mixture in bioreactors and change hydrodynamic regimes in bioreactors. Determination of the coefficient of internal recirculation of sludge mixture between bioreactors is important for the choice of technological parameters of biological treatment (wastewater treatment duration in anoxic and aerobic bioreactors, flow capacity of recirculation pumps). Determination of the coefficient of internal recirculation of sludge mixture requires integrated consideration of hydrodynamic parameter (flow rate), kinetic parameter (rate of oxidation of organic compounds) and physical-chemical parameter of wastewater (concentration of organic compounds). The conducted numerical experiment from the proposed mathematical equations allowed to obtain analytical dependences of the coefficient of internal recirculation sludge mixture between bioreactors on the concentration of organic compounds in wastewater, the duration of wastewater treatment in bioreactors.
Studies on the consistency of internally taken contrast medium for pancreas CT
Energy Technology Data Exchange (ETDEWEB)
Matsushima, Kishio; Mimura, Seiichi; Tahara, Seiji; Kitayama, Takuichi; Inamura, Keiji; Mikami, Yasutaka; Hashimoto, Keiji; Hiraki, Yoshio; Aono, Kaname
1985-02-01
A problem of Pancreatic CT scanning is the discrimination between the pancreas and the adjacent gastrointestinal tract. Generally we administer a dilution of gastrografin internally to make the discrimination. The degree of dilution has been decided by experience at each hospital. When the consistency of the contrast medium is low in density, an enhancement effect cannot be expected, but when the consistency is high, artifacts appear. We have experimented on the degree of the dilution and CT-No to decide the optimum consistency of gastrografin for the diagnosis of pancreatic disease. Statistical analysis of the results show the optimum dilution of gastrografin to be 1.5%.
How Well Does the Sum Score Summarize the Test? Summability as a Measure of Internal Consistency
Goeman, J.J.; De, Jong N.H.
2018-01-01
Many researchers use Cronbach's alpha to demonstrate internal consistency, even though it has been shown numerous times that Cronbach's alpha is not suitable for this. Because the intention of questionnaire and test constructers is to summarize the test by its overall sum score, we advocate
Validity and internal consistency of a whiplash-specific disability measure
Pinfold, Melanie; Niere, Ken R.; O'Leary, Elizabeth F.; Hoving, Jan Lucas; Green, Sally; Buchbinder, Rachelle
2004-01-01
STUDY DESIGN: Cross-sectional study of patients with whiplash-associated disorders investigating the internal consistency, factor structure, response rates, and presence of floor and ceiling effects of the Whiplash Disability Questionnaire (WDQ). OBJECTIVES: The aim of this study was to confirm the
van Heugten, CM; Dekker, J; Deelman, BG; Stehmann-Saris, JC; Kinebanian, A
1999-01-01
In this paper the internal consistency and inter-observer reliability of the assessment of disabilities in stroke patients with apraxia is presented. Disabilities were assessed by means of observation of activities of daily living (ADL). The study was conducted at occupational therapy departments in
Heugten, C.M. van; Dekker, J.; Deelman, B.G.; Stehmann-Saris, J.C.; Kinebanian, A.
1999-01-01
In this paper the internal consistency and inter-observer reliability of the assessment of disabilities in stroke patients with apraxia is presented. Disabilities were assessed by means of observation of activities of daily living (ADL). The study was conducted at occupational therapy departments in
Mekhora, Keerin; Jalayondeja, Wattana; Jalayondeja, Chutima; Bhuanantanondh, Petcharatana; Dusadiisariyavong, Asadang; Upiriyasakul, Rujiret; Anuraktam, Khajornyod
2014-07-01
To develop an online, self-report questionnaire on computer work-related exposure (OSCWE) and to determine the internal consistency, face and content validity of the questionnaire. The online, self-report questionnaire was developed to determine the risk factors related to musculoskeletal disorders in computer users. It comprised five domains: personal, work-related, work environment, physical health and psychosocial factors. The questionnaire's content was validated by an occupational medical doctor and three physical therapy lecturers involved in ergonomic teaching. Twenty-five lay people examined the feasibility of computer-administered and the user-friendly language. The item correlation in each domain was analyzed by the internal consistency (Cronbach's alpha; alpha). The content of the questionnaire was considered congruent with the testing purposes. Eight hundred and thirty-five computer users at the PTT Exploration and Production Public Company Limited registered to the online self-report questionnaire. The internal consistency of the five domains was: personal (alpha = 0.58), work-related (alpha = 0.348), work environment (alpha = 0.72), physical health (alpha = 0.68) and psychosocial factor (alpha = 0.93). The findings suggested that the OSCWE had acceptable internal consistency for work environment and psychosocial factors. The OSCWE is available to use in population-based survey research among computer office workers.
Kinney, Daryl W.
2009-01-01
The purpose of this study was to examine the effects of music experience and excerpt familiarity on the internal consistency of performance evaluations. Participants included nonmusic majors who had not participated in high school music ensembles, nonmusic majors who had participated in high school music ensembles, music majors, and experts…
Pérez V, Cristhian; Vaccarezza G, Giulietta; Aguilar A, César; Coloma N, Katherine; Salgado F, Horacio; Baquedano R, Marjorie; Chavarría R, Carla; Bastías V, Nancy
2016-06-01
Teaching practice is one of the most complex topics of the training process in medicine and other health care careers. The Teaching Practices Questionnaire (TPQ) evaluates teaching skills. To assess the factor structure and internal consistency of the Spanish version of the TPP among health care teachers. The TPQ was answered by 315 university teachers from 13 of the 15 administrative Chilean regions, who were selected through a non-probabilistic volunteer sampling. The internal consistency of TPP factors was calculated and the correlation between them was analyzed. Six factors were identified: Student-centered teaching, Teaching planning, Assessment process, Dialogue relationship, Teacher-centered teaching and Use of technological resources. They had Cronbach alphas ranging from 0.60 to 0.85. The factorial structure of TPQ differentiates the most important functions of teaching. It also shows a theoretical consistency and a practical relevance to perform a diagnosis and continuous evaluation of teaching practices. Additionally, it has an adequate internal consistency. Thus, TPQ is valid and reliable to evaluate pedagogical practices in health care careers.
Rosario, Martín G; Vázquez, Jenniffer M; Cruz, Wanda I; Ortiz, Alexis
2008-09-01
The Community Healthy Activities Model Program for Seniors (CHAMPS) is a physical activity monitoring questionnaire for people between 65 to 90 years old. This questionnaire has been previously translated to Spanish to be used in the Latin American population. To adapt the Spanish version of the CHAMPS questionnaire to Puerto Rico and assess its internal consistency. An external review committee adapted the existent Spanish version of the CHAMPS to be used in the Puerto Rican population. Three older adults participated in a second phase with the purpose of training the research team. After the second phase, 35 older adults participated in a third content adaptation phase. During the third phase, the preliminary Spanish version for Puerto Rico of the CHAMPS was given to the 35 participants to assess for clarity, vocabulary and understandability. Interviews to each participant in the third phase were carried out to obtain feedback and create a final Spanish version of the CHAMPS for Puerto Rico. After analyses of this phase, the external review committee prepared a final Spanish version of the CHAMPS for Puerto Rico. The final version was administered to 15 older adults (76 +/- 6.5 years) to assess the internal consistency by using Cronbach's Alpha analysis. The questionnaire showed a strong internal consistency of 0.76. The total time to answer the questionnaire was 17.4 minutes. The Spanish version of the CHAMPS questionnaire for Puerto Rico suggested being an easy to administer and consistent measurement tool to assess physical activity in older adults.
Shi, Guangsha; Kioupakis, Emmanouil
2018-02-01
We apply density functional and many-body perturbation theory calculations to consistently determine and parameterize the relativistic quasiparticle band structures of Mg2Si, Mg2Ge, and Mg2Sn, and predict the Seebeck coefficient as a function of doping and temperature. The quasiparticle band gaps, including spin-orbit coupling effects, are determined to be 0.728 eV, 0.555 eV, and 0.142 eV for Mg2Si, Mg2Ge, and Mg2Sn, respectively. The inclusion of the semicore electrons of Mg, Ge, and Sn in the valence is found to be important for the accurate determination of the band gaps of Mg2Ge and Mg2Sn. We also developed a Luttinger-Kohn Hamiltonian and determined a set of band parameters to model the near-edge relativistic quasiparticle band structure consistently for all three compounds that can be applied for thermoelectric device simulations. Our calculated values for the Seebeck coefficient of all three compounds are in good agreement with the available experimental data for a broad range of temperatures and carrier concentrations. Our results indicate that quasiparticle corrections are necessary for the accurate determination of Seebeck coefficients at high temperatures at which bipolar transport becomes important.
Energy Technology Data Exchange (ETDEWEB)
Xie, Linjun [Zhejiang Univ. of Technology, Hangzhou (China). College of Mechanical Engineering; Xue, Guohong; Zhang, Ming [Shanghai Nuclear Engineering Research and Design Institute, Shanghai (China)
2017-11-15
The friction force between the contact surfaces of a reactor internal hold-down spring (HDS) and core barrel flanges can directly influence the axial stiffness of an HDS. However, friction coefficient cannot be obtained through theoretical analysis. This study performs a mathematical deduction of the physical model of an HDS. Moreover, a mathematical model of axial load P, displacement δ, and flexibility coefficient is established, and a set of test apparatuses is designed to simulate the preloading process of the HDS. According to the experimental research and theoretical analysis, P-δ curves and the flexibility coefficient λ are obtained in the loading processes of the HDS. The friction coefficient f of the M1000 HDS is further calculated as 0.224. The displacement limit load value (4,638 kN) can be obtained through a displacement limit experiment. With the friction coefficient considered, the theoretical load is 4,271 kN, which is relatively close to the experimental result. Thus, the friction coefficient exerts an influence on the displacement limit load P. The friction coefficient should be considered in the design analysis for HDS.
International Nuclear Information System (INIS)
Xie, Linjun
2017-01-01
The friction force between the contact surfaces of a reactor internal hold-down spring (HDS) and core barrel flanges can directly influence the axial stiffness of an HDS. However, friction coefficient cannot be obtained through theoretical analysis. This study performs a mathematical deduction of the physical model of an HDS. Moreover, a mathematical model of axial load P, displacement δ, and flexibility coefficient is established, and a set of test apparatuses is designed to simulate the preloading process of the HDS. According to the experimental research and theoretical analysis, P-δ curves and the flexibility coefficient λ are obtained in the loading processes of the HDS. The friction coefficient f of the M1000 HDS is further calculated as 0.224. The displacement limit load value (4,638 kN) can be obtained through a displacement limit experiment. With the friction coefficient considered, the theoretical load is 4,271 kN, which is relatively close to the experimental result. Thus, the friction coefficient exerts an influence on the displacement limit load P. The friction coefficient should be considered in the design analysis for HDS.
Calculating the heat transfer coefficient of frame profiles with internal cavities
DEFF Research Database (Denmark)
Noyé, Peter Anders; Laustsen, Jacob Birck; Svendsen, Svend
2004-01-01
. The heat transfer coefficient is determined by two-dimensional numerical calculations and by measurements. Calculations are performed in Therm (LBNL (2001)), which is developed at Lawrence Berkeley National Laboratory, USA. The calculations are performed in accordance with the future European standards...... correspondence between measured and calculated values. Hence, when determining the heat transfer coefficient of frame profiles with internal cavities by calculations, it is necessary to apply a more detailed radiation exchange model than described in the prEN ISO 10077-2 standard. The ISO-standard offers......Determining the energy performance of windows requires detailed knowledge of the thermal properties of their different elements. A series of standards and guidelines exist in this area. The thermal properties of the frame can be determined either by detailed two-dimensional numerical methods...
Internal conversion coefficients for atomic numbers Z less than or equal to 30
International Nuclear Information System (INIS)
Band, I.M.; Trzhaskovskaya, M.B.; Listengarten, M.A.
1976-01-01
Presented here are internal conversion coefficients (ICC) of gamma rays for 20 values of atomic number, Z, in the range 3 less than or equal to Z less than or equal to 30, including all Z greater than or equal to 14. The tables provide the previously missing data for light elements. Coefficients are given for 19 values of gamma-ray transition energies up to 6 MeV for the K-electron shell and 18 values up to 2 MeV for three L-subshells. The minimum enegy is 15 keV. The first five electric and magnetic nuclear transition multipolarities are covered. The calculations are relativistic, with screening and finite nuclear size effect taken into account
Internal Consistency and Convergent Validity of the Klontz Money Behavior Inventory (KMBI
Directory of Open Access Journals (Sweden)
Colby D. Taylor
2015-12-01
Full Text Available The Klontz Money Behavior Inventory (KMBI is a standalone, multi-scale measure than can screen for the presence of eight distinct money disorders. Given the well-established relationship between mental health and financial behaviors, results from the KMBI can be used to inform both mental health care professionals and financial planners. The present study examined the internal consistency and convergent validity of the KMBI, through comparison with similar measures, among a sample of college students (n = 232. Results indicate that the KMBI demonstrates acceptable internal consistency reliability and some convergence for most subscales when compared to other analogous measures. These findings highlight a need for literature and assessments to identify and describe disordered money behaviors.
Internal Consistency, Retest Reliability, and their Implications For Personality Scale Validity
McCrae, Robert R.; Kurtz, John E.; Yamagata, Shinji; Terracciano, Antonio
2010-01-01
We examined data (N = 34,108) on the differential reliability and validity of facet scales from the NEO Inventories. We evaluated the extent to which (a) psychometric properties of facet scales are generalizable across ages, cultures, and methods of measurement; and (b) validity criteria are associated with different forms of reliability. Composite estimates of facet scale stability, heritability, and cross-observer validity were broadly generalizable. Two estimates of retest reliability were independent predictors of the three validity criteria; none of three estimates of internal consistency was. Available evidence suggests the same pattern of results for other personality inventories. Internal consistency of scales can be useful as a check on data quality, but appears to be of limited utility for evaluating the potential validity of developed scales, and it should not be used as a substitute for retest reliability. Further research on the nature and determinants of retest reliability is needed. PMID:20435807
Hedlund, Ann; Ateg, Mattias; Andersson, Ing-Marie; Rosén, Gunnar
2010-04-01
Workers' motivation to actively take part in improvements to the work environment is assumed to be important for the efficiency of investments for that purpose. That gives rise to the need for a tool to measure this motivation. A questionnaire to measure motivation for improvements to the work environment has been designed. Internal consistency and test-retest reliability of the domains of the questionnaire have been measured, and the factorial structure has been explored, from the answers of 113 employees. The internal consistency is high (0.94), as well as the correlation for the total score (0.84). Three factors are identified accounting for 61.6% of the total variance. The questionnaire can be a useful tool in improving intervention methods. The expectation is that the tool can be useful, particularly with the aim of improving efficiency of companies' investments for work environment improvements. Copyright 2010 Elsevier Ltd. All rights reserved.
Martin A. Volker; Elissa H. Dua; Christopher Lopata; Marcus L. Thomeer; Jennifer A. Toomey; Audrey M. Smerbeck; Jonathan D. Rodgers; Joshua R. Popkin; Andrew T. Nelson; Gloria K. Lee
2016-01-01
The Gilliam Autism Rating Scale-Second Edition (GARS-2) is a widely used screening instrument that assists in the identification and diagnosis of autism. The purpose of this study was to examine the factor structure, internal consistency, and screening sensitivity of the GARS-2 using ratings from special education teaching staff for a sample of 240 individuals with autism or other significant developmental disabilities. Exploratory factor analysis yielded a correlated three-factor solution si...
DEFF Research Database (Denmark)
Toldbod, Thomas; Israelsen, Poul
2014-01-01
Companies rely on multiple Management Control Systems to obtain their short and long term objectives. When applying a multifaceted perspective on Management Control System the concept of internal consistency has been found to be important in obtaining goal congruency in the company. However, to d...... management is aware of this shortcoming they use the cybernetic controls more interactively to overcome this shortcoming, whereby the cybernetic controls are also used as a learning platform and not just for performance control....
Recent developments in biokinetic models and the calculation of internal dose coefficients
International Nuclear Information System (INIS)
Fell, T.P.; Phipps, A.W.; Kendall, G.M.; Stradling, G.N.
1997-01-01
In most cases the measurement of radioactivity in an environmental or biological sample will be followed by some estimation of dose and possibly risk, either to a population or an individual. This will normally involve the use of a dose coefficient (dose per unit intake value) taken from a compendium. In recent years the calculation of dose coefficients has seen many developments in both biokinetic modelling and computational capabilities. ICRP has recommended new models for the respiratory tract and for the systemic behavior of many of the more important elements. As well as this, a general age-dependent calculation method has been developed which involves an effectively continuous variation of both biokinetic and dosimetric parameters, facilitating more realistic estimation of doses to young people. These new developments were used in work for recent ICRP, IAEA and CEC compendia of dose coefficients for both members of the public (including children) and workers. This paper presents a general overview of the method of calculation of internal doses with particular reference to the actinides. Some of the implications for dose coefficients of the new models are discussed. For example it is shown that compared with data in ICRP Publications 30 and 54: the new respiratory tract model generally predicts lower deposition in systemic tissues per unit intake; the new biokinetic models for actinides allow for burial of material deposited on bone surfaces; age-dependent models generally feature faster turnover of material in young people. All of these factors can lead to substantially different estimates of dose and examples of the new dose coefficients are given to illustrate these differences. During the development of the new models for actinides, human bioassay data were used to validate the model. Thus, one would expect the new models to give reasonable predictions of bioassay quantities. Some examples of the bioassay applications, e.g., excretion data for the
Validity and internal consistency of a whiplash-specific disability measure.
Pinfold, Melanie; Niere, Ken R; O'Leary, Elizabeth F; Hoving, Jan Lucas; Green, Sally; Buchbinder, Rachelle
2004-02-01
Cross-sectional study of patients with whiplash-associated disorders investigating the internal consistency, factor structure, response rates, and presence of floor and ceiling effects of the Whiplash Disability Questionnaire (WDQ). The aim of this study was to confirm the appropriateness of the proposed WDQ items. Whiplash injuries are a common cause of pain and disability after motor vehicle accidents. Neck disability questionnaires are often used in whiplash studies to assess neck pain but lack content validity for patients with whiplash-associated disorders. The newly developed WDQ measures functional limitations associated with whiplash injury and was designed after interviews with 83 patients with whiplash in a previous study. Researchers sought expert opinion on items of the WDQ, and items were then tested on a clinical whiplash population. Data were inspected to determine floor and ceiling effects, response rates, factor structure, and internal consistency. Packages of questionnaires were distributed to 55 clinicians, whose patients with whiplash completed and returned 101 questionnaires to researchers. No substantial floor or ceiling effects were identified on inspection of data. The overall floor effect was 12%, and the overall ceiling effect was 4%. Principal component analysis identified one broad factor that accounted for 65% of the variance in responses. Internal consistency was high; Cronbach's alpha = 0.96. Results of the study supported the retention of the 13 proposed items in a whiplash-specific disability questionnaire. Dependent on the results of further psychometric testing, the WDQ is likely to be an appropriate outcome measure for patients with whiplash.
Directory of Open Access Journals (Sweden)
Sandeep Grover
2014-01-01
Full Text Available Background & objectives: The Indian Disability Evaluation and Assessment Scale (IDEAS has been recommended for assessment and certification of disability by the Government of India (GOI. However, the psychometric properties of IDEAS as adopted by GOI remain understudied. Our aim, thus, was to study the internal consistency and validity of IDEAS in patients with schizophrenia. Methods: A total of 103 consenting patients with residual schizophrenia were assessed for disability, quality of life (QOL and psychopathology using the IDEAS, WHO QOL-100 and Positive and Negative symptom scale (PANSS respectively. Internal consistency was calculated using Cronbach′s alpha. For construct validity, relations between IDEAS, and psychopathology and QOL were studied. Results: The inter-item correlations for IDEAS were significant with a Cronbach′s alpha of 0.721. All item scores other than score on communication and understanding; total and global IDEAS scores correlated significantly with the positive, negative and general sub-scales, and total PANSS scores. Communication and understanding was significantly related to negative sub-scale score only. Total and global disability scores correlated negatively with all the domains of WHOQOL-100 (ρ<0.01. The individual IDEAS item scores correlated negatively with various WHOQOL-100 domains (ρ0< 0.01. Interpretation & conclusions: This study findings showed that the GOI-modified IDEAS had good internal consistency and construct validity as tested in patients with residual schizophrenia. Similar studies need to be done with other groups of patients.
Wood, Louise; Smith, Michael; Miller, Christopher B; O'Carroll, Ronan E
2018-06-19
Vaccinations are important preventative health behaviors. The recently developed Vaccination Attitudes Examination (VAX) Scale aims to measure the reasons behind refusal/hesitancy regarding vaccinations. The aim of this replication study is to conduct an independent test of the newly developed VAX Scale in the UK. We tested (a) internal consistency (Cronbach's α); (b) convergent validity by assessing its relationships with beliefs about medication, medical mistrust, and perceived sensitivity to medicines; and (c) construct validity by testing how well the VAX Scale discriminated between vaccinators and nonvaccinators. A sample of 243 UK adults completed the VAX Scale, the Beliefs About Medicines Questionnaire, the Perceived Sensitivity to Medicines Scale, and the Medical Mistrust Index, in addition to demographics of age, gender, education levels, and social deprivation. Participants were asked (a) whether they received an influenza vaccination in the past year and (b) if they had a young child, whether they had vaccinated the young child against influenza in the past year. The VAX (a) demonstrated high internal consistency (α = .92); (b) was positively correlated with medical mistrust and beliefs about medicines, and less strongly correlated with perceived sensitivity to medicines; and (c) successfully differentiated parental influenza vaccinators from nonvaccinators. The VAX demonstrated good internal consistency, convergent validity, and construct validity in an independent UK sample. It appears to be a useful measure to help us understand the health beliefs that promote or deter vaccination behavior.
Standardization and determination of the total internal conversion coefficient of In-111.
Matos, Izabela T; Koskinas, Marina F; Nascimento, Tatiane S; Yamazaki, Ione M; Dias, Mauro S
2014-05-01
The standardization of (111)In by means of a 4πβ-γ coincidence system, composed of a proportional counter in 4π geometry, coupled to a 20% relative efficiency HPGe crystal, for measuring gamma-rays is presented. The data acquisition was performed by means of the software coincidence system (SCS) and the activity was determined by the extrapolation technique. Two gamma-ray windows were selected: at 171 keV and 245 keV total absorption peaks, allowing the determination of the total internal conversion coefficient for these two gamma transitions. The results were compared with those available in the literature. © 2013 Published by Elsevier Ltd.
International Nuclear Information System (INIS)
Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Choi, Yong Ho
2009-01-01
Traditionally, radiation protection has been focused on a radiation exposure of human beings. In the international radiation protection community, one of the recent key issues is to establish the methodology for assessing the radiological impact of an ionizing radiation on non-human species for an environmental protection. To assess the radiological impact to non-human species dose conversion coefficients are essential. This paper describes the methodology to calculate the internal dose conversion coefficient for non-human species and presents calculated internal dose conversion coefficients of 25 radionuclides for 8 domestic reference animal and plants
Study of the coefficients of internal conversion for transition energies approaching the threshold
International Nuclear Information System (INIS)
Farani Coursol, Nelcy.
1979-01-01
Internal conversion coefficients were determined experimentally with great accuracy for areas of transition energies, which constitute tests for the theories (energies at the most ten kEv above the threshold of K shell), then the results obtained were compared with the values calculated (or to be calculated) from theoretical models. Owing to the difficulties raised by the precise determination of the internal conversion coefficients (ICC), in the first stage we selected radionuclides with a relatively simple decay pattern, the transitions: 30 keV of sup(93m)Nb, 35 keV of sup(125m)Te, 14 keV of 57 Fe and 39 keV of sup(129m)Xe. It was observed that 'problems' exist with respect to the ICC's of the great multipolarity transitions, so the transitions of this kind were examined in a systematic manner. The possibility of penetration effects occurring for the transitions studied experimentally was examined. The considerations are presented which 'authorized' us to disregard the dynamic part of the ICC for the transitions approaching the threshold (L selection rules and life of nuclear levels in relation to Weisskopf-Moszkowski estimations). The Kurie straight line was determined experimentally for the β - transition and the Qsub(β) was evaluated with an important accuracy gain compared with the values available at present. Finally, a certain number of ICC's of transitions already determined with good precision were recalculated, in order to extend our analysis and detect any possible systematic errors [fr
Internal and external dose conversion coefficient for domestic reference animals and plant
Energy Technology Data Exchange (ETDEWEB)
Keum, Dong Kwon; Jun, In; Lim, Kwang Muk; Park, Du Won; Choi, Young Ho
2009-07-15
This report presents the internal and external dose conversion coefficients for domestic reference animals and plant, which are essential to assess the radiological impact of an environmental radiation on non-human species. To calculate the dose conversion coefficients, a uniform isotropic model and a Monte Carlo method for a photon transport simulation in environmental media with different densities have been applied for aquatic and terrestrial animals, respectively. In the modeling all the target animals are defined as a simple 3D elliptical shape. To specify the external radiation source it is assumed that aquatic animals are fully immersed in infinite and uniformly contaminated water, and the on-soil animals are living on the surface of a horizontally infinite soil source, and the in-soil organisms are living at the center of a horizontally infinite and uniformly contaminated soil to a depth of 50cm. A set of internal and external dose conversion coefficients for 8 Korean reference animals and plant (rat, roe-deer, frog, snake, Chinese minnow, bee, earthworm, and pine tree) are presented for 25 radionuclides ({sup 3}H, {sup 7}Be, {sup 14}C, {sup 40}K, {sup 51}Cr, {sup 54}Mn, {sup 59}Fe, {sup 58}Co, {sup 60}Co, {sup 65}Zn, {sup 90}Sr, {sup 95}Zr, {sup 95}Nb, {sup 99}Tc, {sup 106}Ru, {sup 129}I, {sup 131}I, {sup 136}Cs, {sup 137}Cs, {sup 140}Ba, {sup 140}La, {sup 144}Ce, {sup 238}U, {sup 239}Pu, and {sup 240}Pu)
Aerts, Bas R; Kuijer, P Paul; Beumer, Annechien; Eygendaal, Denise; Frings-Dresen, Monique H
2018-04-17
To test a 17-item questionnaire, the WOrk-Related Questionnaire for UPper extremity disorders (WORQ-UP), for dimensionality of the items (factor analysis) and internal consistency. Cross-sectional study. Outpatient clinic. A consecutive sample of patients (N=150) consisting of all new referral patients (either from a general physician or other hospital) who visited the orthopedic outpatient clinic because of an upper extremity musculoskeletal disorder. Not applicable. Number and dimensionality of the factors in the WORQ-UP. Four factors with eigenvalues (EVs) >1.0 were found. The factors were named exertion, dexterity, tools & equipment, and mobility. The EVs of the factors were, respectively, 5.78, 2.38, 1.81, and 1.24. The factors together explained 65.9% of the variance. The Cronbach alpha values for these factors were, respectively, .88, .74, .87, and .66. The 17 items of the WORQ-UP resemble 4 factors-exertion, dexterity, tools & equipment, and mobility-with a good internal consistency. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Factorial Validity and Internal Consistency of the Motivational Climate in Physical Education Scale
Directory of Open Access Journals (Sweden)
Markus Soini
2014-03-01
Full Text Available The aim of the study was to examine the construct validity and internal consistency of the Motivational Climate in Physical Education Scale (MCPES. A key element of the development process of the scale was establishing a theoretical framework that integrated the dimensions of task- and ego involving climates in conjunction with autonomy, and social relatedness supporting climates. These constructs were adopted from the self-determination and achievement goal theories. A sample of Finnish Grade 9 students, comprising 2,594 girls and 1,803 boys, completed the 18-item MCPES during one physical education class. The results of the study demonstrated that participants had highest mean in task-involving climate and the lowest in autonomy climate and ego-involving climate. Additionally, autonomy, social relatedness, and task- involving climates were significantly and strongly correlated with each other, whereas the ego- involving climate had low or negligible correlations with the other climate dimensions.The construct validity of the MCPES was analyzed using confirmatory factor analysis. The statistical fit of the four-factor model consisting of motivational climate factors supporting perceived autonomy, social relatedness, task-involvement, and ego-involvement was satisfactory. The results of the reliability analysis showed acceptable internal consistencies for all four dimensions. The Motivational Climate in Physical Education Scale can be considered as psychometrically valid tool to measure motivational climate in Finnish Grade 9 students.
Directory of Open Access Journals (Sweden)
Martin A. Volker
2016-01-01
Full Text Available The Gilliam Autism Rating Scale-Second Edition (GARS-2 is a widely used screening instrument that assists in the identification and diagnosis of autism. The purpose of this study was to examine the factor structure, internal consistency, and screening sensitivity of the GARS-2 using ratings from special education teaching staff for a sample of 240 individuals with autism or other significant developmental disabilities. Exploratory factor analysis yielded a correlated three-factor solution similar to that found in 2005 by Lecavalier for the original GARS. Though the three factors appeared to be reasonably consistent with the intended constructs of the three GARS-2 subscales, the analysis indicated that more than a third of the GARS-2 items were assigned to the wrong subscale. Internal consistency estimates met or exceeded standards for screening and were generally higher than those in previous studies. Screening sensitivity was .65 and specificity was .81 for the Autism Index using a cut score of 85. Based on these findings, recommendations are made for instrument revision.
Factorial validity and internal consistency of the motivational climate in physical education scale.
Soini, Markus; Liukkonen, Jarmo; Watt, Anthony; Yli-Piipari, Sami; Jaakkola, Timo
2014-01-01
The aim of the study was to examine the construct validity and internal consistency of the Motivational Climate in Physical Education Scale (MCPES). A key element of the development process of the scale was establishing a theoretical framework that integrated the dimensions of task- and ego involving climates in conjunction with autonomy, and social relatedness supporting climates. These constructs were adopted from the self-determination and achievement goal theories. A sample of Finnish Grade 9 students, comprising 2,594 girls and 1,803 boys, completed the 18-item MCPES during one physical education class. The results of the study demonstrated that participants had highest mean in task-involving climate and the lowest in autonomy climate and ego-involving climate. Additionally, autonomy, social relatedness, and task- involving climates were significantly and strongly correlated with each other, whereas the ego- involving climate had low or negligible correlations with the other climate dimensions.The construct validity of the MCPES was analyzed using confirmatory factor analysis. The statistical fit of the four-factor model consisting of motivational climate factors supporting perceived autonomy, social relatedness, task-involvement, and ego-involvement was satisfactory. The results of the reliability analysis showed acceptable internal consistencies for all four dimensions. The Motivational Climate in Physical Education Scale can be considered as psychometrically valid tool to measure motivational climate in Finnish Grade 9 students. Key PointsThis study developed Motivational Climate in School Physical Education Scale (MCPES). During the development process of the scale, the theoretical framework using dimensions of task- and ego involving as well as autonomy, and social relatedness supporting climates was constructed. These constructs were adopted from the self-determination and achievement goal theories.The statistical fit of the four-factor model of the
Link between self-consistent pressure profiles and electron internal transport barriers in tokamaks
Energy Technology Data Exchange (ETDEWEB)
Razumova, K A [Nuclear Fusion Institute, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Andreev, V F [Nuclear Fusion Institute, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Donne, A J H [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Hogeweij, G M D [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Lysenko, S E [Nuclear Fusion Institute, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Shelukhin, D A [Nuclear Fusion Institute, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Spakman, G W [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster, PO Box 1207, 3430 BE Nieuwegein (Netherlands); Vershkov, V A [Nuclear Fusion Institute, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation); Zhuravlev, V A [Nuclear Fusion Institute, RRC ' Kurchatov Institute' , 123182 Moscow (Russian Federation)
2006-09-15
Tokamak plasmas have a tendency to self-organization: the plasma pressure profiles obtained in different operational regimes and even in various tokamaks may be represented by a single typical curve, called the self-consistent pressure profile. About a decade ago local zones with enhanced confinement were discovered in tokamak plasmas. These zones are referred to as internal transport barriers (ITBs) and they can act on the electron and/or ion fluid. Here the pressure gradients can largely exceed the gradients dictated by profile consistency. So the existence of ITBs seems to be in contradiction with the self-consistent pressure profiles (this is also often referred to as profile resilience or profile stiffness). In this paper we will discuss the interplay between profile consistency and ITBs. A summary of the cumulative information obtained from T-10, RTP and TEXTOR is given, and a coherent explanation of the main features of the observed phenomena is suggested. Both phenomena, the self-consistent profile and ITB, are connected with the density of rational magnetic surfaces, where the turbulent cells are situated. The distance between these cells determines the level of their interaction, and therefore the level of the turbulent transport. This process regulates the plasma pressure profile. If the distance is wide, the turbulent flux may be diminished and the ITB may be formed. In regions with rarefied surfaces the steeper pressure gradients are possible without instantaneously inducing pressure driven instabilities, which force the profiles back to their self-consistent shapes. Also it can be expected that the ITB region is wider for lower dq/d{rho} (more rarefied surfaces)
Test of Gross Motor Development : Expert Validity, confirmatory validity and internal consistence
Directory of Open Access Journals (Sweden)
Nadia Cristina Valentini
2008-12-01
Full Text Available The Test of Gross Motor Development (TGMD-2 is an instrument used to evaluate children’s level of motordevelopment. The objective of this study was to translate and verify the clarity and pertinence of the TGMD-2 items by expertsand the confirmatory factorial validity and the internal consistence by means of test-retest of the Portuguese TGMD-2. Across-cultural translation was used to construct the Portuguese version. The participants of this study were 7 professionalsand 587 children, from 27 schools (kindergarten and elementary from 3 to 10 years old (51.1% boys and 48.9% girls.Each child was videotaped performing the test twice. The videotaped tests were then scored. The results indicated thatthe Portuguese version of the TGMD-2 contains clear and pertinent motor items; demonstrated satisfactory indices ofconfirmatory factorial validity (χ2/gl = 3.38; Goodness-of-fit Index = 0.95; Adjusted Goodness-of-fit index = 0.92 and Tuckerand Lewis’s Index of Fit = 0.83 and test-retest internal consistency (locomotion r = 0.82; control of object: r = 0.88. ThePortuguese TGMD-2 demonstrated validity and reliability for the sample investigated.
Test of Gross Motor Development: expert validity, confirmatory validity and internal consistence
Directory of Open Access Journals (Sweden)
Nadia Cristina Valentini
2008-01-01
The Test of Gross Motor Development (TGMD-2 is an instrument used to evaluate children’s level of motor development. The objective of this study was to translate and verify the clarity and pertinence of the TGMD-2 items by experts and the confirmatory factorial validity and the internal consistence by means of test-retest of the Portuguese TGMD-2. A cross-cultural translation was used to construct the Portuguese version. The participants of this study were 7 professionals and 587 children, from 27 schools (kindergarten and elementary from 3 to 10 years old (51.1% boys and 48.9% girls. Each child was videotaped performing the test twice. The videotaped tests were then scored. The results indicated that the Portuguese version of the TGMD-2 contains clear and pertinent motor items; demonstrated satisfactory indices of confirmatory factorial validity (÷2/gl = 3.38; Goodness-of-fit Index = 0.95; Adjusted Goodness-of-fit index = 0.92 and Tucker and Lewis’s Index of Fit = 0.83 and test-retest internal consistency (locomotion r = 0.82; control of object: r = 0.88. The Portuguese TGMD-2 demonstrated validity and reliability for the sample investigated.
Crestani, Anelise Henrich; Moraes, Anaelena Bragança de; Souza, Ana Paula Ramos de
2017-08-10
To analyze the results of the validation of building enunciative signs of language acquisition for children aged 3 to 12 months. The signs were built based on mechanisms of language acquisition in an enunciative perspective and on clinical experience with language disorders. The signs were submitted to judgment of clarity and relevance by a sample of six experts, doctors in linguistic in with knowledge of psycholinguistics and language clinic. In the validation of reliability, two judges/evaluators helped to implement the instruments in videos of 20% of the total sample of mother-infant dyads using the inter-evaluator method. The method known as internal consistency was applied to the total sample, which consisted of 94 mother-infant dyads to the contents of the Phase 1 (3-6 months) and 61 mother-infant dyads to the contents of Phase 2 (7 to 12 months). The data were collected through the analysis of mother-infant interaction based on filming of dyads and application of the parameters to be validated according to the child's age. Data were organized in a spreadsheet and then converted to computer applications for statistical analysis. The judgments of clarity/relevance indicated no modifications to be made in the instruments. The reliability test showed an almost perfect agreement between judges (0.8 ≤ Kappa ≥ 1.0); only the item 2 of Phase 1 showed substantial agreement (0.6 ≤ Kappa ≥ 0.79). The internal consistency for Phase 1 had alpha = 0.84, and Phase 2, alpha = 0.74. This demonstrates the reliability of the instruments. The results suggest adequacy as to content validity of the instruments created for both age groups, demonstrating the relevance of the content of enunciative signs of language acquisition.
Hicks, Brian M.; DiRago, Ana C.; Iacono, William G.; McGue, Matt
2009-01-01
Background Newer behavior genetic methods can better elucidate gene-environment (G-E) interplay in the development of internalizing (INT) disorders (i.e., major depression and anxiety disorders). However, no study to date has conducted a comprehensive analysis examining multiple environmental risks with the purpose of delineating how general G-E mechanisms influence the development of INT disorders. Methods The sample consisted of 1315 male and female twin pairs participating in the age 17 assessment of the Minnesota Twin Family Study. Quantitative G-E interplay models were used to examine how genetic and environmental risk for INT disorders changes as a function of environmental context. Multiple measures and informants were employed to construct composite measures of INT disorders and 6 environmental risk factors including: stressful life events, mother-child and father-child relationship problems, antisocial and prosocial peer affiliation, and academic achievement and engagement. Results Significant moderation effects were detected between each environmental risk factor and INT such that in the context of greater environmental adversity, nonshared environmental factors became more important in the etiology of INT symptoms. Conclusion Our results are consistent with the interpretation that environmental stressors have a causative effect on the emergence of INT disorders. The consistency of our results suggests a general mechanism of environmental influence on INT disorders regardless of the specific form of environmental risk. PMID:19594836
DEFF Research Database (Denmark)
Huang, Lei; Fantke, Peter; Jolliet, Olivier
2017-01-01
of chemical-material combinations. This paper develops and evaluates a quantitative property-property relationship (QPPR) to predict diffusion coefficients for a wide range of organic chemicals and materials. We first compiled a training dataset of 1103 measured diffusion coefficients for 158 chemicals in 32......Indoor releases of organic chemicals encapsulated in solid materials are major contributors to human exposures and are directly related to the internal diffusion coefficient in solid materials. Existing correlations to estimate the diffusion coefficient are only valid for a limited number...... consolidated material types. Following a detailed analysis of the temperature influence, we developed a multiple linear regression model to predict diffusion coefficients as a function of chemical molecular weight (MW), temperature, and material type (adjusted R2 of 0.93). The internal validations showed...
Hosford, Charles C; Siders, William A
2010-10-01
Strategies to facilitate learning include using knowledge of students' learning style preferences to inform students and their teachers. Aims of this study were to evaluate the factor structure, internal consistency, and temporal stability of medical student responses to the Index of Learning Styles (ILS) and determine its appropriateness as an instrument for medical education. The ILS assesses preferences on four dimensions: sensing/intuitive information perceiving, visual/verbal information receiving, active/reflective information processing, and sequential/global information understanding. Students entering the 2002-2007 classes completed the ILS; some completed the ILS again after 2 and 4 years. Analyses of responses supported the ILS's intended structure and moderate reliability. Students had moderate preferences for sensing and visual learning. This study provides evidence supporting the appropriateness of the ILS for assessing learning style preferences in medical students.
The memory failures of everyday questionnaire (MFE): internal consistency and reliability.
Montejo Carrasco, Pedro; Montenegro, Peña Mercedes; Sueiro, Manuel J
2012-07-01
The Memory Failures of Everyday Questionnaire (MFE) is one of the most widely-used instruments to assess memory failures in daily life. The original scale has nine response options, making it difficult to apply; we created a three-point scale (0-1-2) with response choices that make it easier to administer. We examined the two versions' equivalence in a sample of 193 participants between 19 and 64 years of age. The test-retest reliability and internal consistency of the version we propose were also computed in a sample of 113 people. Several indicators attest to the two forms' equivalence: the correlation between the items' means (r = .94; p MFE 1-9. The MFE 0-2 provides a brief, simple evaluation, so we recommend it for use in clinical practice as well as research.
Towards consistent and reliable Dutch and international energy statistics for the chemical industry
International Nuclear Information System (INIS)
Neelis, M.L.; Pouwelse, J.W.
2008-01-01
Consistent and reliable energy statistics are of vital importance for proper monitoring of energy-efficiency policies. In recent studies, irregularities have been reported in the Dutch energy statistics for the chemical industry. We studied in depth the company data that form the basis of the energy statistics in the Netherlands between 1995 and 2004 to find causes for these irregularities. We discovered that chemical products have occasionally been included, resulting in statistics with an inconsistent system boundary. Lack of guidance in the survey for the complex energy conversions in the chemical industry in the survey also resulted in large fluctuations for certain energy commodities. The findings of our analysis have been the basis for a new survey that has been used since 2007. We demonstrate that the annual questionnaire used for the international energy statistics can result in comparable problems as observed in the Netherlands. We suggest to include chemical residual gas as energy commodity in the questionnaire and to include the energy conversions in the chemical industry in the international energy statistics. In addition, we think the questionnaire should be explicit about the treatment of basic chemical products produced at refineries and in the petrochemical industry to avoid system boundary problems
Directory of Open Access Journals (Sweden)
Susanne Kristen
2014-01-01
Full Text Available Mental state language, emerging in the second and third years of life in typically developing children, is one of the first signs of an explicit psychological understanding. While mental state vocabulary may serve a variety of conversational functions in discourse and thus might not always indicate psychological comprehension, there is evidence for genuine references to mental states (desires, knowledge, beliefs, and emotions early in development across languages. This present study presents parental questionnaire data on the composition of 297 toddler-aged (30-to 32-month-olds children’s internal state vocabulary in four languages: Italian, German, English, and French. The results demonstrated that across languages expressions for physiological states (e.g., hungry and tired were among the most varied, while children’s vocabulary for cognitive entities (e.g., know and think proved to be least varied. Further, consistent with studies on children’s comprehension of these concepts, across languages children’s mastery of volition terms (e.g., like to do and want preceded their mastery of cognition terms. These findings confirm the cross-linguistic consistency of children’s emerging expression of abstract psychological concepts.
Assessing the internal consistency of the CARINA database in the Indian sector of the Southern Ocean
Directory of Open Access Journals (Sweden)
C. Lo Monaco
2010-02-01
Full Text Available Carbon and carbon-relevant hydrographic and hydrochemical ancillary data from previously not publicly available cruises were retrieved and recently merged to a new data base, CARINA (CARbon IN the Atlantic. The initial North Atlantic project, an international effort for ocean carbon synthesis, was extended to include the Arctic Mediterranean Seas (Arctic Ocean and Nordic Seas and all three sectors of the Southern Ocean. Of a total of 188 cruises, 37 cruises are part of the Southern Ocean. The present work focuses on data collected in the Indian sector (20° S–70° S; 30° E–150° E. The Southern Indian Ocean dataset covers the period 1992–2004 and includes seasonal repeated observations. Parameters including salinity, dissolved inorganic carbon (TCO_{2}, total alkalinity (TA, oxygen, nitrate, phosphate and silicate were examined for cruise-to-cruise and overall consistency. In addition, data from an existing, quality controlled data base (GLODAP were introduced in the CARINA analysis to improve data coverage in the Southern Ocean. A global inversion was performed to synthesize the information deduced from objective comparisons of deep measurements (>1500 m at nearby stations (generally <220 km. The corrections suggested by the inversion were allowed to vary within a fixed envelope, thus accounting for ocean interior variability. The adjustments applied to CARINA data and those recommended for GLODAP data, in order to obtain a consistent merged dataset, are presented and discussed. The final outcome of this effort is a new quality controlled data base for TCO_{2} and other properties of the carbon system that can now be used to investigate the natural variability or stability of ocean chemistry and the accumulation of anthropogenic carbon. This data product also offers an important new synthesis of seasonal to decadal observations to validate ocean biogeochemical models in a region where available historical data were very
Pure E2 transitions: A test for BRICC Internal Conversion Coefficients
International Nuclear Information System (INIS)
Gerl, J.; Sai, K. Vijay; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K.
2009-01-01
The most widely used theoretical internal conversion coefficient (ICC) tables are of Hager and Seltzer (HS), Rosel et al. and BRICC (Band et al. tables using BRICC interpolation code). A rigorous comparison of experimental ICCs with various theoretical tabulations is possible only when a large data on experimental ICCs is available at one place. For this reason, a compilation of all the available experimental ICCs, α T , α K , α L of E2 transitions for a number of elements in the range of 24≤Z≤94 is presented. Listing of experimental data includes 595 datasets corresponding to 505 E2 transitions in 165 nuclei across the nuclear chart. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer, Rosel et al. and BRICC. The relative percentage deviation (%Δ) have been calculated for each of the above theories and the average (%Δ) are estimated. The Band et al. tables, using the BRICC interpolation code are seen to give theoretical ICCs closest to experimental values.
International Nuclear Information System (INIS)
Nishiyama, Seiya; Providencia, Joao da; Komatsu, Takao
2007-01-01
To go beyond perturbative method in terms of variables of collective motion, using infinite-dimensional fermions, we have aimed to construct the self-consistent-field (SCF) theory, i.e., time dependent Hartree-Fock theory on associative affine Kac-Moody algebras along the soliton theory. In this paper, toward such an ultimate goal we will reconstruct a theoretical frame for a υ (external parameter)-dependent SCF method to describe more precisely the dynamics on the infinite-dimensional fermion Fock space. An infinite-dimensional fermion operator is introduced through Laurent expansion of finite-dimensional fermion operators with respect to degrees of freedom of the fermions related to a υ-dependent and a Υ-periodic potential. As an illustration, we derive explicit expressions for the Laurent coefficients of soliton solutions for sl n and for su n on infinite-dimensional Grassmannian. The associative affine Kac-Moody algebras play a crucial role to determine the dynamics on the infinite-dimensional fermion Fock space
Dhawan, Vibhu; Spratt, Kevin F; Pinzur, Michael S; Baumhauer, Judith; Rudicel, Sally; Saltzman, Charles L
2005-09-01
The development of Charcot changes is known to be associated with a high rate of recurrent ulceration and amputation. Unfortunately, the effect of Charcot arthropathy on quality of life in diabetic patients has not been systematically studied because of a lack of a disease-specific instrument. The purpose of this study was to develop and test an instrument to evaluate the health-related quality of life of diabetic foot disease. Subjects diagnosed with Charcot arthropathy completed a patient self-administered questionnaire, and clinicians completed an accompanying observational survey. The patient self-administered questionnaire was organized into five general sections: demographics, general health, diabetes-related symptoms, comorbidities, and satisfaction. The scales measured the effect in six health domains: 1) general health, 2) care, 3) worry, 4) sleep, 5) emotion, and 6) physicality. The psychometric properties of the scales were evaluated and the summary scores for the Short-Form Health Survey (SF-36) were compared to published norms for other major medical illnesses. Of the 89 enrolled patients, 57 who completed the questionnaire on enrollment returned a second completed form at 3-month followup. Over the 3-month followup period most of the patients showed an improvement in the Eichenholtz staging. The internal consistency of most was moderate to high and, in general, the scale scores were stable over 3 months. However, several of the scales suffered from low-ceiling or high-floor effects. Patients with Charcot arthropathy had a much lower physical component score on enrollment than the reported norms for other disease conditions, including diabetes. Quality of life represents an important set of outcomes when evaluating the effectiveness of treatment for patients with Charcot arthropathy. This study represents an initial attempt to develop a standardized survey for use with this patient population. Further studies need to be done with larger groups of
Directory of Open Access Journals (Sweden)
Marcelo Feijó de Mello
2010-04-01
Full Text Available As experiências traumáticas precoces são um fator de risco preditivo de problemas psicopatológicos futuros. O Early Trauma Inventory (ETI é um instrumento que avalia em indivíduos adultos experiências traumáticas ocorridas antes dos 18 anos de idade. Tal instrumento foi traduzido, transculturalmente adaptado e sua consistência interna foi avaliada. Vítimas de violência que preencheram os critérios de inclusão e exclusão foram submetidas a uma entrevista diagnóstica (SCID-I e ao ETI. Foram incluídos 91 pacientes com o transtorno do estresse pós-traumático (TEPT. O alfa de Cronbach nos diferentes domínios variou de 0,595-0,793, e o escore total foi de 0,878. A maior parte dos itens nos vários domínios, com exceção do abuso emocional, apresentou índices de correlação interitem entre 0,51-0,99. A versão adaptada foi útil tanto na clínica quanto na pesquisa. Apresentou boa consistência interna e na correlação interitem. O ETI é um instrumento válido, com boa consistência para se avaliar a presença de história de traumas precoces em indivíduos adultos.Early life stress is a strong predictor of future psychopathology during adulthood. The Early Trauma Inventory (ETI was developed to detect the presence and impact of traumatic experiences that occurred up to 18 years of age. The ETI was translated and cross-culturally adapted and had its consistency evaluated. Victims of violence that met the inclusion and exclusion criteria were submitted to SCID-I and ETI. Ninety-one patients with post-traumatic stress disorder (PTSD were included. Cronbach's alpha in the different domains varied from 0.595 to 0.793, and the total score was 0.878. Except for emotional abuse, most of the various domains displayed inter-item correlation rates of 0.51 to 0.99. The adapted version was useful for clinical and research purposes and showed good internal consistency and inter-item correlation. The ETI is a valid instrument with good
Shaw, Jacob T.; Lidster, Richard T.; Cryer, Danny R.; Ramirez, Noelia; Whiting, Fiona C.; Boustead, Graham A.; Whalley, Lisa K.; Ingham, Trevor; Rickard, Andrew R.; Dunmore, Rachel E.; Heard, Dwayne E.; Lewis, Ally C.; Carpenter, Lucy J.; Hamilton, Jacqui F.; Dillon, Terry J.
2018-03-01
Gas-phase rate coefficients are fundamental to understanding atmospheric chemistry, yet experimental data are not available for the oxidation reactions of many of the thousands of volatile organic compounds (VOCs) observed in the troposphere. Here, a new experimental method is reported for the simultaneous study of reactions between multiple different VOCs and OH, the most important daytime atmospheric radical oxidant. This technique is based upon established relative rate concepts but has the advantage of a much higher throughput of target VOCs. By evaluating multiple VOCs in each experiment, and through measurement of the depletion in each VOC after reaction with OH, the OH + VOC reaction rate coefficients can be derived. Results from experiments conducted under controlled laboratory conditions were in good agreement with the available literature for the reaction of 19 VOCs, prepared in synthetic gas mixtures, with OH. This approach was used to determine a rate coefficient for the reaction of OH with 2,3-dimethylpent-1-ene for the first time; k = 5.7 (±0.3) × 10-11 cm3 molecule-1 s-1. In addition, a further seven VOCs had only two, or fewer, individual OH rate coefficient measurements available in the literature. The results from this work were in good agreement with those measurements. A similar dataset, at an elevated temperature of 323 (±10) K, was used to determine new OH rate coefficients for 12 aromatic, 5 alkane, 5 alkene and 3 monoterpene VOC + OH reactions. In OH relative reactivity experiments that used ambient air at the University of York, a large number of different VOCs were observed, of which 23 were positively identified. Due to difficulties with detection limits and fully resolving peaks, only 19 OH rate coefficients were derived from these ambient air samples, including 10 reactions for which data were previously unavailable at the elevated reaction temperature of T = 323 (±10) K.
International Nuclear Information System (INIS)
Kim, K.S.; Kim, T.H.
1982-01-01
Internal friction peaks associated with the presence of carbon in 18-8 type 304 stainless steel have been observed from measurements with a torsion pendulum. The temperature for maximum internal friction lies between 250degC and 300degC with a frequency of vibration. The height of the peak rises and the position of the peak shifts to a lower temperature with an increase of the carbon content. And a comparison of the activation energy and the diffusion coefficient determined by internal friction methods with those measured in conventional macro-diffusion experiments reveals that the diffusion data measured by internal friction method and the diffusion data measured by conventional method exist in the same line. It follows from the above fact that observed internal friction peak is associated with the stress-induced diffusion of carbon in face-centered cubic alloys. (Author)
Francis, L J; Katz, Y J
2000-08-01
The Hebrew translation of the Oxford Happiness Inventory and the short form Revised Eysenck Personality Questionnaire were completed by 298 undergraduate women in Israel. The findings confirm the internal reliability of the Hebrew translation of the Oxford Happiness Inventory and support the construct validity according to which "happiness is a thing called stable extraversion."
Alkhateeb, Haitham M
2004-06-01
The Arabic translation of the Mathematics Teaching Efficacy Beliefs was completed by 144 undergraduate students (M age=20.6) in Jordan. The findings support the internal reliability of the Arabic translation of the Mathematics Teaching Efficacy Beliefs as well as its construct validity.
Hicks, Brian M.; Dirago, Ana C.; Iacono, William G.; McGue, Matt
2009-01-01
Background: Behavior genetic methods can help to elucidate gene-environment (G-E) interplay in the development of internalizing (INT) disorders (i.e., major depression and anxiety disorders). To date, however, no study has conducted a comprehensive analysis examining multiple environmental risk factors with the purpose of delineating general…
International Nuclear Information System (INIS)
Strosnider, J.
2004-01-01
International commerce of radioactive materials crosses national boundaries, linking separate regulatory institutions with a common purpose and making it necessary for these institutions to work together in order to achieve common safety goals in a manner that does not place an undue burden on industry and commerce. Widespread and increasing use of radioactive materials across the world has led to increases in the transport of radioactive materials. The demand for consistency in the oversight of international transport has also increased to prevent unnecessary delays and costs associated with incongruent or redundant regulatory requirements by the various countries through which radioactive material is transported. The International Atomic Energy Agency (IAEA) is the authority for international regulation of transportation of radioactive materials responsible for promulgation of regulations and guidance for the establishment of acceptable methods of transportation for the international community. As such, the IAEA is seen as the focal point for consensus building between its Member States to develop consistency in transportation regulations and reviews and to ensure the safe and secure transport of radioactive material. International cooperation is also needed to ensure stability in our regulatory processes. Changes to transportation regulations should be based on an anticipated safety benefit supported by risk information and insights gained from continuing experience, evaluation, and research studies. If we keep safety as the principle basis for regulatory changes, regulatory stability will be enhanced. Finally, as we endeavour to maintain consistency and stability in our international regulations, we must be mindful of the new security challenges that lay before the international community as a result of a changing terrorist environment. Terrorism is a problem of global concern that also requires international cooperation and support, as we look for ways to
Bessette, Douglas L; Campbell-Arvai, Victoria; Arvai, Joseph
2016-05-01
This article presents research aimed at developing and testing an online, multistakeholder decision-aiding framework for informing multiattribute risk management choices associated with energy development and climate change. The framework was designed to provide necessary background information and facilitate internally consistent choices, or choices that are in line with users' prioritized objectives. In order to test different components of the decision-aiding framework, a six-part, 2 × 2 × 2 factorial experiment was conducted, yielding eight treatment scenarios. The three factors included: (1) whether or not users could construct their own alternatives; (2) the level of detail regarding the composition of alternatives users would evaluate; and (3) the way in which a final choice between users' own constructed (or highest-ranked) portfolio and an internally consistent portfolio was presented. Participants' self-reports revealed the framework was easy to use and providing an opportunity to develop one's own risk-management alternatives (Factor 1) led to the highest knowledge gains. Empirical measures showed the internal consistency of users' decisions across all treatments to be lower than expected and confirmed that providing information about alternatives' composition (Factor 2) resulted in the least internally consistent choices. At the same time, those users who did not develop their own alternatives and were not shown detailed information about the composition of alternatives believed their choices to be the most internally consistent. These results raise concerns about how the amount of information provided and the ability to construct alternatives may inversely affect users' real and perceived internal consistency. © 2015 Society for Risk Analysis.
The internal consistency and validity of the Self-assessment Parkinson's Disease Disability Scale.
Biemans, M.A.J.E.; Dekker, J.; Woude, L.H.V. van der
2001-01-01
OBJECTIVE: To test the consistency and validity of the Self-assessment Parkinson's Disease Disability Scale in patients with Parkinson's disease living at home. DESIGN: Patients with Parkinson's disease responded to a set of questionnaires. In addition, an observation of the performance of daily
Dekker, J.; Biemans, M.A.J.E.; Woude, L.H.V. van der
2000-01-01
OBJECTIVE: To test the consistency and validity of the Self-assessment Parkinson's Disease Disability Scale in patients with Parkinson's disease living at home. DESIGN: Patients with Parkinson's disease responded to a set of questionnaires. In addition, an observation of the performance of daily
International Nuclear Information System (INIS)
Li Qing; Ren Xin; Zhang Kangda
2009-01-01
Using the finite element method, calculation and test are conducted on the bolted joints of four different diameters, and the existing calculation method for bolt compliance coefficient is analyzed. The results indicate that the calculated and test results by finite element method are agreed well, and value D/t f and β have a linear relation. (authors)
Directory of Open Access Journals (Sweden)
J. T. Shaw
2018-03-01
Full Text Available Gas-phase rate coefficients are fundamental to understanding atmospheric chemistry, yet experimental data are not available for the oxidation reactions of many of the thousands of volatile organic compounds (VOCs observed in the troposphere. Here, a new experimental method is reported for the simultaneous study of reactions between multiple different VOCs and OH, the most important daytime atmospheric radical oxidant. This technique is based upon established relative rate concepts but has the advantage of a much higher throughput of target VOCs. By evaluating multiple VOCs in each experiment, and through measurement of the depletion in each VOC after reaction with OH, the OH + VOC reaction rate coefficients can be derived. Results from experiments conducted under controlled laboratory conditions were in good agreement with the available literature for the reaction of 19 VOCs, prepared in synthetic gas mixtures, with OH. This approach was used to determine a rate coefficient for the reaction of OH with 2,3-dimethylpent-1-ene for the first time; k = 5.7 (±0.3 × 10−11 cm3 molecule−1 s−1. In addition, a further seven VOCs had only two, or fewer, individual OH rate coefficient measurements available in the literature. The results from this work were in good agreement with those measurements. A similar dataset, at an elevated temperature of 323 (±10 K, was used to determine new OH rate coefficients for 12 aromatic, 5 alkane, 5 alkene and 3 monoterpene VOC + OH reactions. In OH relative reactivity experiments that used ambient air at the University of York, a large number of different VOCs were observed, of which 23 were positively identified. Due to difficulties with detection limits and fully resolving peaks, only 19 OH rate coefficients were derived from these ambient air samples, including 10 reactions for which data were previously unavailable at the elevated reaction temperature of T = 323 (±10 K.
International Nuclear Information System (INIS)
Ruskov, T.
1998-01-01
The magnetic disorder-order transition in the Rh-Fe alloy is studied by conversion electron Moessbauer spectroscopy. The drastic increase of the area under the Moessbauer spectrum at the transition from the paramagnetic to the magnetic state could be explained by diminishing the internal conversion coefficient. Thus our experimental results directly confirm the theory of the collective effect in the system of radiating developed by Yukalov
Chahoud, M; Chahine, R; Salameh, P; Sauleau, E A
2017-06-01
Our goal is to validate and to verify the reliability of the French and English versions of the Insomnia Severity Index (ISI) in Lebanese adolescents. A cross-sectional study was implemented. 104 Lebanese students aged between 14 and 19 years participated in the study. The English version of the questionnaire was distributed to English-speaking students and the French version was administered to French-speaking students. A scale (1 to 7 with 1 = very well understood and 7 = not at all) was used to identify the level of the students' understanding of each instruction, question and answer of the ISI. The scale's structural validity was assessed. The factor structure of ISI was evaluated by principal component analysis. The internal consistency of this scale was evaluated by Cronbach's alpha. To assess test-retest reliability the intraclass correlation coefficient (ICC) was used. The principal component analysis confirmed the presence of a two-component factor structure in the English version and a three-component factor structure in the French version with eigenvalues > 1. The English version of the ISI had an excellent internal consistency (α = 0.90), while the French version had a good internal consistency (α = 0.70). The ICC presented an excellent agreement in the French version (ICC = 0.914, CI = 0.856-0.949) and a good agreement in the English one (ICC = 0.762, CI = 0.481-890). The Bland-Altman plots of the two versions of the ISI showed that the responses over two weeks' were comparable and very few outliers were detected. The results of our analyses reveal that both English and French versions of the ISI scale have good internal consistency and are reproducible and reliable. Therefore, it can be used to assess the prevalence of insomnia in Lebanese adolescents.
International Nuclear Information System (INIS)
Heidrich, P; Wolfersdorf, J v; Schmidt, S; Schnieder, M
2008-01-01
This paper describes a non-invasive, non-destructive, transient inverse measurement technique that allows one to determine internal heat transfer coefficients and rib positions of real gas turbine blades from outer surface temperature measurements after a sudden flow heating. The determination of internal heat transfer coefficients is important during the design process to adjust local heat transfer to spatial thermal load. The detection of rib positions is important during production to fulfill design and quality requirements. For the analysis the one-dimensional transient heat transfer problem inside of the turbine blade's wall was solved. This solution was combined with the Levenberg-Marquardt method to estimate the unknown boundary condition by an inverse technique. The method was tested with artificial data to determine uncertainties with positive results. Then experimental testing with a reference model was carried out. Based on the results, it is concluded that the presented inverse technique could be used to determine internal heat transfer coefficients and to detect rib positions of real turbine blades.
Sinval, Jorge; Pasian, Sonia; Queirós, Cristina; Marôco, João
2018-01-01
The aim of this paper is to present a revision of international versions of the Utrecht Work Engagement Scale and to describe the psychometric properties of a Portuguese version of the UWES-9 developed simultaneously for Brazil and Portugal, the validity evidence related with the internal structure, namely, Dimensionality, measurement invariance between Brazil and Portugal, and Reliability of the scores. This is the first UWES version developed simultaneously for both countries, and it is an important instrument for understanding employees' work engagement in the organizations, allowing human resources departments to better use workforces, especially when they are migrants. A total of 524 Brazilian workers and 522 Portuguese workers participated in the study. Confirmatory Factor Analysis, group comparisons, and Reliability estimates were used. The use of workers who were primarily professionals or administrative support, according to ISCO-08, reinforced the need to collect data on other professional occupations. Confirmatory factor analysis showed acceptable fit for the UWES-9 original three-factor solution, and a second-order factor structure has been proposed that presented an acceptable fit. Full-scale invariance was obtained between the Portuguese and Brazilian samples, both for the original three-factor first-order and second-order models. Data revealed that Portuguese and Brazilian workers didn't show statistically significant differences in the work engagement dimensions. This version allows for direct comparisons of means and, consequently, for performance of comparative and cross-cultural studies between these two countries.
Directory of Open Access Journals (Sweden)
Jorge Sinval
2018-03-01
Full Text Available The aim of this paper is to present a revision of international versions of the Utrecht Work Engagement Scale and to describe the psychometric properties of a Portuguese version of the UWES-9 developed simultaneously for Brazil and Portugal, the validity evidence related with the internal structure, namely, Dimensionality, measurement invariance between Brazil and Portugal, and Reliability of the scores. This is the first UWES version developed simultaneously for both countries, and it is an important instrument for understanding employees' work engagement in the organizations, allowing human resources departments to better use workforces, especially when they are migrants. A total of 524 Brazilian workers and 522 Portuguese workers participated in the study. Confirmatory Factor Analysis, group comparisons, and Reliability estimates were used. The use of workers who were primarily professionals or administrative support, according to ISCO-08, reinforced the need to collect data on other professional occupations. Confirmatory factor analysis showed acceptable fit for the UWES-9 original three-factor solution, and a second-order factor structure has been proposed that presented an acceptable fit. Full-scale invariance was obtained between the Portuguese and Brazilian samples, both for the original three-factor first-order and second-order models. Data revealed that Portuguese and Brazilian workers didn't show statistically significant differences in the work engagement dimensions. This version allows for direct comparisons of means and, consequently, for performance of comparative and cross-cultural studies between these two countries.
Item wording and internal consistency of a measure of cohesion: the group environment questionnaire.
Eys, Mark A; Carron, Albert V; Bray, Steven R; Brawley, Lawrence R
2007-06-01
A common practice for counteracting response acquiescence in psychological measures has been to employ both negatively and positively worded items. However, previous research has highlighted that the reliability of measures can be affected by this practice (Spector, 1992). The purpose of the present study was to examine the effect that the presence of negatively worded items has on the internal reliability of the Group Environment Questionnaire (GEQ). Two samples (N = 276) were utilized, and participants were asked to complete the GEQ (original and revised) on separate occasions. Results demonstrated that the revised questionnaire (containing all positively worded items) had significantly higher Cronbach alpha values for three of the four dimensions of the GEQ. Implications, alternatives, and future directions are discussed.
W. Brad Smith
2009-01-01
This article takes a brief chronological look at resource inventory and reporting and links to international influences. It explores events as drivers of more consistent data within the United States and highlights key dates and events in the evolution of inventory policy and practice. From King George to L?Ecole nationale forestiere to the Food and Agriculture...
Steenstra, Ivan A.; Sluiter, Judith K.; Frings-Dresen, Monique H. W.
2009-01-01
The internal consistency and test-retest reliability of a 10-item eye-complaint questionnaire (ECQ) were examined within a sample of office workers. Repeated within-subjects measures were performed within a single day and over intervals of 1 and 7 d. Questionnaires were completed by 96 workers (70%
Ceballos, Guillermo A.; Suescun, Jesus D.; Oviedo, Heidi C.; Herazo, Edwin; Campo-Arias, Adalberto
2015-01-01
The Spanish version of the five-item Francis scale of attitude toward Christianity is a refinement of the short version of the Francis scale of attitude toward Christianity. The scale is a good measurement for intrinsic religiosity. It has been applied previously among Colombian adolescent students. The internal consistency and construct and…
Steultjens, M.P.M.; Dekker, J.; Baar, M.E. van; Oostendorp, R.A.B.; Bijlsma, J.W.J.
1999-01-01
Objective: To establish the internal consistency of validity of an observational method for assessing diasbility in mobility in patients with osteoarthritis (OA), Methods: Data were obtained from 198 patients with OA of the hip or knee. Results of the observational method were compared with results
Steultjens, M. P.; Dekker, J.; van Baar, M. E.; Oostendorp, R. A.; Bijlsma, J. W.
1999-01-01
To establish the internal consistency and validity of an observational method for assessing disability in mobility in patients with osteoarthritis (OA). Data were obtained from 198 patients with OA of the hip or knee. Results of the observational method were compared with results of self-report
Internal Consistency of the easyCBM© CCSS Reading Measures: Grades 3-8. Technical Report #1407
Guerreiro, Meg; Alonzo, Julie; Tindal, Gerald
2014-01-01
This technical report documents findings from a study of the internal consistency and split-half reliability of the easyCBM© CCSS Reading measures, grades 3-8. Data, drawn from an extant data set gathered in school year 2013-2014, include scores from over 150,000 students' fall and winter benchmark assessments. Findings suggest that the easyCBM©…
Ferreira, Mariana Cândido; Björklund, Martin; Dach, Fabiola; Chaves, Thais Cristina
The purpose of this study was to adapt and evaluate the psychometric properties of the ProFitMap-neck to Brazilian Portuguese. The cross-cultural adaptation consisted of 5 stages, and 180 female patients with chronic neck pain participated in the study. A subsample (n = 30) answered the pretest, and another subsample (n = 100) answered the questionnaire a second time. Internal consistency, test-retest reliability, and construct validity (hypothesis testing and structural validity) were estimated. For construct validity, the scores of the questionnaire were correlated with the Neck Disability Index (NDI), and the Hospital Anxiety and Depression Scale (HADS), the Tampa Scale of Kinesiophobia (TSK), and the 36-item Short-Form Health Survey (SF-36). Internal consistency was determined by adequate Cronbach's α values (α > 0.70). Strong reliability was identified by high intraclass correlation coefficients (ICC > 0.75). Construct validity was identified by moderate and strong correlations of the Br-ProFitMap-neck with total NDI score (-0.56 50%, Kaiser-Meyer-Olkin index > 0.50, eigenvalue > 1, and factor loadings > 0.2. Br-ProFitMap-neck had adequate psychometric properties and can be used in clinical settings, as well as research, in patients with chronic neck pain. Copyright © 2017. Published by Elsevier Inc.
An International Disaster Management SensorWeb Consisting of Space-based and Insitu Sensors
Mandl, D.; Frye, S. W.; Policelli, F. S.; Cappelaere, P. G.
2009-12-01
For the past year, NASA along with partners consisting of the United Nations Space-based Information for Disaster and Emergency Response (UN-SPIDER) office, the Canadian Space Agency, the Ukraine Space Research Institute (SRI), Taiwan National Space Program Office (NSPO) and in conjunction with the Committee on Earth Observing Satellite (CEOS) Working Group on Information Systems and Services (WGISS) have been conducting a pilot project to automate the process of obtaining sensor data for the purpose of flood management and emergency response. This includes experimenting with flood prediction models based on numerous meteorological satellites and a global hydrological model and then automatically triggering follow up high resolution satellite imagery with rapid delivery of data products. This presentation will provide a overview of the effort, recent accomplishments and future plans.
Directory of Open Access Journals (Sweden)
Patrick Lumbroso
2016-09-01
Full Text Available The Katz-Francis Scale of Attitude toward Judaism was developed initially to extend among the Hebrew-speaking Jewish community in Israel a growing body of international research concerned to map the correlates, antecedents and consequences of individual differences in attitude toward religion as assessed by the Francis Scale of Attitude toward Christianity. The present paper explored the internal consistency reliability and construct validity of the English translation of the Katz-Francis Scale of Attitude toward Judaism among 101 Australian Jews. On the basis of these data, this instrument is commended for application in further research.
Dobson, J; McLaughlan, G
2001-01-01
This article presents some findings of a recent study carried out for the Home Office by the Migration Research Unit (MRU) in the Department of Geography at UCL. The study was concerned with patterns and trends in international migration to and from the United Kingdom since 1975, with a particular focus on those in employment, and drew on many sources. The statistics analysed here derive from the International Passenger Survey, including hitherto unpublished tables provided by the Office for National Statistics on migration of the employed by citizenship. They indicate remarkable consistency in some aspects of migration flows and major change in others.
DEFF Research Database (Denmark)
Svane, Axel; Christensen, Niels Egede; Cardona,, M.
2010-01-01
The electronic band structures of PbS, PbSe, and PbTe in the rocksalt structure are calculated with the quasiparticle self-consistent GW (QSGW) approach with spin-orbit coupling included. The semiconducting gaps and their deformation potentials as well as the effective masses are obtained. The GW...
Sheahan, Peter J; Nelson-Wong, Erika J; Fischer, Steven L
2015-01-01
The Oswestry Disability Index (ODI) is a self-report-based outcome measure used to quantify the extent of disability related to low back pain (LBP), a substantial contributor to workplace absenteeism. The ODI tool has been adapted for use by patients in several non-English speaking nations. It is unclear, however, if these adapted versions of the ODI are as credible as the original ODI developed for English-speaking nations. The objective of this study was to conduct a review of the literature to identify culturally adapted versions of the ODI and to report on the adaptation process, construct validity, test-retest reliability and internal consistency of these ODIs. Following a pragmatic review process, data were extracted from each study with regard to these four outcomes. While most studies applied adaptation processes in accordance with best-practice guidelines, there were some deviations. However, all studies reported high-quality psychometric properties: group mean construct validity was 0.734 ± 0.094 (indicated via a correlation coefficient), test-retest reliability was 0.937 ± 0.032 (indicated via an intraclass correlation coefficient) and internal consistency was 0.876 ± 0.047 (indicated via Cronbach's alpha). Researchers can be confident when using any of these culturally adapted ODIs, or when comparing and contrasting results between cultures where these versions were employed. Implications for Rehabilitation Low back pain is the second leading cause of disability in the world, behind only cancer. The Oswestry Disability Index (ODI) has been developed as a self-report outcome measure of low back pain for administration to patients. An understanding of the various cross-cultural adaptations of the ODI is important for more concerted multi-national research efforts. This review examines 16 cross-cultural adaptations of the ODI and should inform the work of health care and rehabilitation professionals.
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Brian P. Johnson
2017-07-01
Full Text Available Background: With the increasing complexity of care, people with disabilities and supportive significant others (SSO must often coordinate key aspects of their own care, but no validated scale currently exists to comprehensively characterize the activities done to manage and coordinate their care. Method: This study aimed to improve the feasibility, acceptability, and content validity of the Care and Service Coordination and Management (CASCAM scale and to test its internal consistency. Questionnaire items were administered to 23 individuals with acquired brain injury and 17 SSO. Results: Respondents confirmed content validity and that the instrument addresses important care coordination and management issues. The internal consistency of care coordination domains for medical/ rehabilitative and independent living needs for people with brain injury and their SSO ranged from α = .774 to .945. Conclusion: Care coordination activities by persons with disabilities, including brain injury, and their SSO are multifaceted but feasibly measurable and should be assessed to improve care.
Hairul Anuar Hashim; Freddy Golok; Rosmatunisah Ali
2011-01-01
Background: Psychometrically sound measurement instrument is a fundamental requirement across broad range of research areas. In negative affect research, Depression Anxiety Stress Scale (DASS) has been identified as a psychometrically sound instrument to measure depression, anxiety and stress, especially the 21-item version. However, its psychometric properties in adolescents have been less consistent. Objectives: Thus, the present study sought to examine the factorial validity and internal c...
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Gustavo J. Fonseca D'El Rey
2007-01-01
Full Text Available CONTEXTO: A fobia social é um grave transtorno de ansiedade que traz incapacitação e sofrimento. OBJETIVOS: Investigar a consistência interna da versão em português do Mini-Inventário de Fobia Social (Mini-SPIN. MÉTODOS: Foi realizado um estudo da consistência interna do Mini-SPIN em uma amostra de 206 estudantes universitários da cidade de São Paulo, SP. RESULTADOS: A consistência interna do instrumento, analisada pelo coeficiente alfa de Cronbach, foi de 0,81. CONCLUSÕES: Esses achados permitiram concluir que a versão em português do Mini-SPIN exibiu resultados de boa consistência interna, semelhantes aos da versão original em inglês.BACKGROUND: Social phobia is a severe anxiety disorder that brings disability and distress. OBJECTIVES: To investigate the internal consistency of the Portuguese version of the Mini-Social Phobia Inventory (Mini-SPIN. METHODS: We conducted a study of internal consistency of the Mini-SPIN in a sample of 206 college students of the city of São Paulo, SP. RESULTS: The internal consistency of the instrument, analyzed by Cronbach's alpha coefficient, was 0.81. CONCLUSIONS: These findings suggest that the Portuguese version of the Mini-SPIN has a good internal consistency, similar to those obtained with the original English version.
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Şandru Mirela
2016-09-01
Full Text Available This paper presents an analytical study which deals with the behavior of the circular plates in bending theory, considering the soil-structure interaction under Winkler's hypothesis. It was intended to illustrate the variation of internal forces and deformations according to the flexibility coefficient of plates considering three models: a fixed solid circular plate subjected to a uniformly distributed load, a fixed solid circular plate acted by a displacement applied on the exterior contour and a solid plate subjected to a temperature gradient. For this study the computation relations were written as a product between a dimensional and a non-dimensional factor, the last one indicating the variation of internal forces and deformations. For each type of action there are presented results obtained using the finite element method to illustrate the differences between this method and the analytical computation.
International Nuclear Information System (INIS)
Rosikhin, Ahmad; Winata, Toto
2016-01-01
Internal transmission profile in charges carrier generation layer of graphene/Si based solar cell has been explored theoretically. Photovoltaic device was constructed from graphene/Si heterojunction forming a multilayer stuck with Si as generation layer. The graphene/Si sheet was layered on ITO/glass wafer then coated by Al forming Ohmic contact with Si. Photon incident propagate from glass substrate to metal electrode and assumed that there is no transmission in Al layer. The wavelength range spectra used in this calculation was 200 – 1000 nm. It found that transmission intensity in the generation layer show non-linear behavior and partitioned by few areas which related with excitation process. According to this information, it may to optimize the photons absorption to create more excitation process by inserting appropriate material to enhance optical properties in certain wavelength spectra because of the exciton generation is strongly influenced by photon absorption.
Wang, Hsin; Porter, Wallace D.; Böttner, Harald; König, Jan; Chen, Lidong; Bai, Shengqiang; Tritt, Terry M.; Mayolet, Alex; Senawiratne, Jayantha; Smith, Charlene; Harris, Fred; Gilbert, Patricia; Sharp, Jeff W.; Lo, Jason; Kleinke, Holger; Kiss, Laszlo
2013-04-01
Recent research and development of high-temperature thermoelectric materials has demonstrated great potential for converting automobile exhaust heat directly into electricity. Thermoelectrics based on classic bismuth telluride have also started to impact the automotive industry by enhancing air-conditioning efficiency and integrated cabin climate control. In addition to engineering challenges of making reliable and efficient devices to withstand thermal and mechanical cycling, the remaining issues in thermoelectric power generation and refrigeration are mostly materials related. The dimensionless figure of merit, ZT, still needs to be improved from the current value of 1.0 to 1.5 to above 2.0 to be competitive with other alternative technologies. In the meantime, the thermoelectric community could greatly benefit from the development of international test standards, improved test methods, and better characterization tools. Internationally, thermoelectrics have been recognized by many countries as a key component for improving energy efficiency. The International Energy Agency (IEA) group under the Implementing Agreement for Advanced Materials for Transportation (AMT) identified thermoelectric materials as an important area in 2009. This paper is part I of the international round-robin testing of transport properties of bulk thermoelectrics. The main foci in part I are the measurement of two electronic transport properties: Seebeck coefficient and electrical resistivity.
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Eduardo de Paula Lima
2012-01-01
Full Text Available INTRODUCTION: Posttraumatic stress disorder (PTSD is an anxiety disorder resulting from exposure to traumatic events. The Posttraumatic Stress Disorder Checklist (PCL is a self-report measure largely used to evaluate the presence of PTSD. OBJECTIVE: To investigate the internal consistency, temporal reliability and factor validity of the Portuguese language version of the PCL used in Brazil. METHODS: A total of 186 participants were recruited. The sample was heterogeneous with regard to occupation, sociodemographic data, mental health history, and exposure to traumatic events. Subjects answered the PCL at two occasions within a 15 days’ interval (range: 5-15 days. RESULTS: Cronbach’s alpha coefficients indicated high internal consistency for the total scale (0.91 and for the theoretical dimensions of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV (0.83, 0.81, and 0.80. Temporal reliability (test-retest was high and consistent for different cutoffs. Maximum likelihood exploratory factor analysis (EFA was conducted and oblique rotation (Promax was applied. The Kaiser-Meyer-Olkin (KMO index (0.911 and Bartlett’s test of sphericity (χ² = 1,381.34, p INTRODUÇÃO: O transtorno do estresse pós-traumático (TEPT é um transtorno de ansiedade decorrente da exposição a eventos traumáticos. Entre as medidas de avaliação dos sintomas, destaca-se o Posttraumatic Stress Disorder Checklist (PCL. OBJETIVO: Investigar a consistência interna, a confiabilidade temporal e a validade fatorial da versão do PCL em português, utilizada no Brasil. MÉTODOS: Participaram do estudo 186 indivíduos heterogêneos em relação a ocupação, características sociodemográficas, histórico de saúde mental e exposição a eventos traumáticos. O PCL foi aplicado em dois momentos considerando um intervalo máximo de 15 dias (intervalo: 5-15 dias. RESULTADOS: A consistência interna (alfa de Cronbach foi adequada para a escala
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Guzik Agnieszka
2016-09-01
Full Text Available Introduction: A proper assessment of gait pattern is a significant aspect in planning the process of teaching gait in hemiparetic post-stroke patients. The Wisconsin Gait Scale (WGS is an observational tool for assessing post-stroke patients’ gait. The aim of the study was to assess test-retest reliability and internal consistency of the WGS and examine correlations between gait assessment made with the WGS and gait speed, Brunnström scale, Ashworth’s scale and the Barthel Index.
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Mousavi Sayed
2009-09-01
Full Text Available Abstract Background The 12-item Short Form Health Survey (SF-12 as a shorter alternative of the SF-36 is largely used in health outcomes surveys. The aim of this study was to validate the SF-12 in Iran. Methods A random sample of the general population aged 15 years and over living in Tehran, Iran completed the SF-12. Reliability was estimated using internal consistency and validity was assessed using known groups comparison and convergent validity. In addition, the factor structure of the questionnaire was extracted by performing both exploratory factor analysis (EFA and confirmatory factor analysis (CFA. Results: In all, 5587 individuals were studied (2721 male and 2866 female. The mean age and formal education of the respondents were 35.1 (SD = 15.4 and 10.2 (SD = 4.4 years respectively. The results showed satisfactory internal consistency for both summary measures, that are the Physical Component Summary (PCS and the Mental Component Summary (MCS; Cronbach's α for PCS-12 and MCS-12 was 0.73 and 0.72, respectively. Known-groups comparison showed that the SF-12 discriminated well between men and women and those who differed in age and educational status (P Conclusion In general the findings suggest that the SF-12 is a reliable and valid measure of health related quality of life among Iranian population. However, further studies are needed to establish stronger psychometric properties for this alternative form of the SF-36 Health Survey in Iran.
Internal conversion coefficients of M4 isomeric transitions in /sup 125/ /sup 127/ /sup 129/Te decay
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Soni, S K; Kumar, A; Gupta, S L; Pancholi, S C [Delhi Univ. (India). Dept. of Physics and Astrophysics
1977-01-01
The internal conversion coefficients have been measured using a high resolution low energy Ge(Li) detector for the following M4 transitions: /sup 125/Te: 109.27 keV transition ..cap alpha..sub(T) = 357 +- 11; RG method, /sup 127/Te: 88,26 keV transition ..cap alpha..sub(K) = 484 +- 23; XPG method, /sup 129/Te: 105.50 keV transition ..cap alpha..sub(K) = 213 +- 10; XPG method. It is observed that these values are lower by 2.5-3.6% as compared with Hager and Seltzer's calculations. A comparison between experimental and theoretical ..cap alpha..sub(K) and ..cap alpha..sub(T) values for eleven M4 transitions shows that the experimental values are systematically lower.
Prior, Sandra; Hufton, Simon E; Fox, Bernard; Dougall, Thomas; Rigsby, Peter; Bristow, Adrian
2018-01-01
The intrinsic complexity and heterogeneity of therapeutic monoclonal antibodies is built into the biosimilarity paradigm where critical quality attributes are controlled in exhaustive comparability studies with the reference medicinal product. The long-term success of biosimilars will depend on reassuring healthcare professionals and patients of consistent product quality, safety and efficacy. With this aim, the World Health Organization has endorsed the need for public bioactivity standards for therapeutic monoclonal antibodies in support of current controls. We have developed a candidate international potency standard for rituximab that was evaluated in a multi-center collaborative study using participants' own qualified Fc-effector function and cell-based binding bioassays. Dose-response curve model parameters were shown to reflect similar behavior amongst rituximab preparations, albeit with some differences in potency. In the absence of a common reference standard, potency estimates were in poor agreement amongst laboratories, but the use of the candidate preparation significantly reduced this variability. Our results suggest that the candidate rituximab standard can support bioassay performance and improve data harmonization, which when implemented will promote consistency of rituximab products over their life-cycles. This data provides the first scientific evidence that a classical standardization exercise allowing traceability of bioassay data to an international standard is also applicable to rituximab. However, we submit that this new type of international standard needs to be used appropriately and its role not to be mistaken with that of the reference medicinal product.
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Ismaïl Amany
2009-03-01
Full Text Available Abstract Background The objectives of this study were to test the factor structure and internal consistency of the 12-item General Health Questionnaire (GHQ-12 and the Subjective Vitality Scale (VS in elderly French people, and to test the relationship between these two questionnaires. Methods Using a standard 'forward-backward' translation procedure, the English language versions of the two instruments (i.e. the 12-item General Health Questionnaire and the Subjective Vitality Scale were translated into French. A sample of adults aged 58–72 years then completed both questionnaires. Internal consistency was assessed by Cronbach's alpha coefficient. The factor structures of the two instruments were extracted by confirmatory factor analysis (CFA. Finally, the relationship between the two instruments was assessed by correlation analysis. Results In all, 217 elderly adults participated in the study. The mean age of the respondents was 61.7 (SD = 6.2 years. The mean GHQ-12 score was 17.4 (SD = 8.0, and analysis showed satisfactory internal consistency (Cronbach's alpha coefficient = 0.78. The mean VS score was 22.4 (SD = 7.4 and its internal consistency was found to be good (Cronbach's alpha coefficient = 0.83. While CFA showed that the VS was uni-dimensional, analysis for the GHQ-12 demonstrated a good fit not only to the two-factor model (positive vs. negative items but also to a three-factor model. As expected, there was a strong and significant negative correlation between the GHQ-12 and the VS (r = -0.71, P Conclusion The results showed that the French versions of the 12-item General Health Questionnaire (GHQ-12 and the Subjective Vitality Scale (VS are reliable measures of psychological distress and vitality. They also confirm a significant negative correlation between these two instruments, lending support to their convergent validity in an elderly French population. The findings indicate that both measures have good structural
Deleanu, Ioana Sorina
2017-01-01
Indicators of compliance and efficiency in combatting money laundering, collected by EUROSTAT, are plagued with shortcomings. In this paper, I have carried out a forensic analysis on a 2003-2010 dataset of indicators of compliance and efficiency in combatting money laundering, that European Union member states self-reported to EUROSTAT, and on the basis of which, their efforts were evaluated. I used Benford's law to detect any anomalous statistical patterns and found that statistical anomalies were also consistent with strategic manipulation. According to Benford's law, if we pick a random sample of numbers representing natural processes, and look at the distribution of the first digits of these numbers, we see that, contrary to popular belief, digit 1 occurs most often, then digit 2, and so on, with digit 9 occurring in less than 5% of the sample. Without prior knowledge of Benford's law, since people are not intuitively good at creating truly random numbers, deviations thereof can capture strategic alterations. In order to eliminate other sources of deviation, I have compared deviations in situations where incentives and opportunities for manipulation existed and in situations where they did not. While my results are not a conclusive proof of strategic manipulation, they signal that countries that faced incentives and opportunities to misinform the international community about their efforts to combat money laundering may have manipulated these indicators. Finally, my analysis points to the high potential for disruption that the manipulation of national statistics has, and calls for the acknowledgment that strategic manipulation can be an unintended consequence of the international community's pressure on countries to put combatting money laundering on the top of their national agenda.
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Ioana Sorina Deleanu
Full Text Available Indicators of compliance and efficiency in combatting money laundering, collected by EUROSTAT, are plagued with shortcomings. In this paper, I have carried out a forensic analysis on a 2003-2010 dataset of indicators of compliance and efficiency in combatting money laundering, that European Union member states self-reported to EUROSTAT, and on the basis of which, their efforts were evaluated. I used Benford's law to detect any anomalous statistical patterns and found that statistical anomalies were also consistent with strategic manipulation. According to Benford's law, if we pick a random sample of numbers representing natural processes, and look at the distribution of the first digits of these numbers, we see that, contrary to popular belief, digit 1 occurs most often, then digit 2, and so on, with digit 9 occurring in less than 5% of the sample. Without prior knowledge of Benford's law, since people are not intuitively good at creating truly random numbers, deviations thereof can capture strategic alterations. In order to eliminate other sources of deviation, I have compared deviations in situations where incentives and opportunities for manipulation existed and in situations where they did not. While my results are not a conclusive proof of strategic manipulation, they signal that countries that faced incentives and opportunities to misinform the international community about their efforts to combat money laundering may have manipulated these indicators. Finally, my analysis points to the high potential for disruption that the manipulation of national statistics has, and calls for the acknowledgment that strategic manipulation can be an unintended consequence of the international community's pressure on countries to put combatting money laundering on the top of their national agenda.
Montazeri, Ali; Vahdaninia, Mariam; Mousavi, Sayed Javad; Omidvari, Speideh
2009-09-16
The 12-item Short Form Health Survey (SF-12) as a shorter alternative of the SF-36 is largely used in health outcomes surveys. The aim of this study was to validate the SF-12 in Iran. A random sample of the general population aged 15 years and over living in Tehran, Iran completed the SF-12. Reliability was estimated using internal consistency and validity was assessed using known groups comparison and convergent validity. In addition, the factor structure of the questionnaire was extracted by performing both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). In all, 5587 individuals were studied (2721 male and 2866 female). The mean age and formal education of the respondents were 35.1 (SD = 15.4) and 10.2 (SD = 4.4) years respectively. The results showed satisfactory internal consistency for both summary measures, that are the Physical Component Summary (PCS) and the Mental Component Summary (MCS); Cronbach's alpha for PCS-12 and MCS-12 was 0.73 and 0.72, respectively. Known-groups comparison showed that the SF-12 discriminated well between men and women and those who differed in age and educational status (P < 0.001). In addition, correlations between the SF-12 scales and single items showed that the physical functioning, role physical, bodily pain and general health subscales correlated higher with the PCS-12 score, while the vitality, social functioning, role emotional and mental health subscales more correlated with the MCS-12 score lending support to its good convergent validity. Finally the principal component analysis indicated a two-factor structure (physical and mental health) that jointly accounted for 57.8% of the variance. The confirmatory factory analysis also indicated a good fit to the data for the two-latent structure (physical and mental health). In general the findings suggest that the SF-12 is a reliable and valid measure of health related quality of life among Iranian population. However, further studies are needed to
Cole, Jason C; Ito, Diane; Chen, Yaozhu J; Cheng, Rebecca; Bolognese, Jennifer; Li-McLeod, Josephine
2014-09-04
There is a lack of validated instruments to measure the level of burden of Alzheimer's disease (AD) on caregivers. The Impact of Alzheimer's Disease on Caregiver Questionnaire (IADCQ) is a 12-item instrument with a seven-day recall period that measures AD caregiver's burden across emotional, physical, social, financial, sleep, and time aspects. Primary objectives of this study were to evaluate psychometric properties of IADCQ administered on the Web and to determine most appropriate scoring algorithm. A national sample of 200 unpaid AD caregivers participated in this study by completing the Web-based version of IADCQ and Short Form-12 Health Survey Version 2 (SF-12v2™). The SF-12v2 was used to measure convergent validity of IADCQ scores and to provide an understanding of the overall health-related quality of life of sampled AD caregivers. The IADCQ survey was also completed four weeks later by a randomly selected subgroup of 50 participants to assess test-retest reliability. Confirmatory factor analysis (CFA) was implemented to test the dimensionality of the IADCQ items. Classical item-level and scale-level psychometric analyses were conducted to estimate psychometric characteristics of the instrument. Test-retest reliability was performed to evaluate the instrument's stability and consistency over time. Virtually none (2%) of the respondents had either floor or ceiling effects, indicating the IADCQ covers an ideal range of burden. A single-factor model obtained appropriate goodness of fit and provided evidence that a simple sum score of the 12 items of IADCQ can be used to measure AD caregiver's burden. Scales-level reliability was supported with a coefficient alpha of 0.93 and an intra-class correlation coefficient (for test-retest reliability) of 0.68 (95% CI: 0.50-0.80). Low-moderate negative correlations were observed between the IADCQ and scales of the SF-12v2. The study findings suggest the IADCQ has appropriate psychometric characteristics as a
Reimer, Janet J.; Cai, Wei-Jun; Xue, Liang; Vargas, Rodrigo; Noakes, Scott; Hu, Xinping; Signorini, Sergio R.; Mathis, Jeremy T.; Feely, Richard A.; Sutton, Adrienne J.; Sabine, Christopher; Musielewicz, Sylvia; Chen, Baoshan; Wanninkhof, Rik
2017-08-01
Marine carbonate system monitoring programs often consist of multiple observational methods that include underway cruise data, moored autonomous time series, and discrete water bottle samples. Monitored parameters include all, or some of the following: partial pressure of CO2 of the water (pCO2w) and air, dissolved inorganic carbon (DIC), total alkalinity (TA), and pH. Any combination of at least two of the aforementioned parameters can be used to calculate the others. In this study at the Gray's Reef (GR) mooring in the South Atlantic Bight (SAB) we: examine the internal consistency of pCO2w from underway cruise, moored autonomous time series, and calculated from bottle samples (DIC-TA pairing); describe the seasonal to interannual pCO2w time series variability and air-sea flux (FCO2), as well as describe the potential sources of pCO2w variability; and determine the source/sink for atmospheric pCO2. Over the 8.5 years of GR mooring time series, mooring-underway and mooring-bottle calculated-pCO2w strongly correlate with r-values > 0.90. pCO2w and FCO2 time series follow seasonal thermal patterns; however, seasonal non-thermal processes, such as terrestrial export, net biological production, and air-sea exchange also influence variability. The linear slope of time series pCO2w increases by 5.2 ± 1.4 μatm y-1 with FCO2 increasing 51-70 mmol m-2 y-1. The net FCO2 sign can switch interannually with the magnitude varying greatly. Non-thermal pCO2w is also increasing over the time series, likely indicating that terrestrial export and net biological processes drive the long term pCO2w increase.
International Nuclear Information System (INIS)
Arqueros, F.; Campos, J.
1986-01-01
The method used for efficiency calibration of a magnetic electron spectrometer and its applications to conversion electron spectrometry is described. The present results point out that apparatus combining magnetic deflection and semiconductor detection have a nondecreasing interest in nuclear spectrometry for applications where good resolution and large background rejection are both necessary. The present apparatus can be employed with source of relatively low activity, (0.lμCi). The nuclides studied were 129 Xe and 77 Se resulting from 129 Cs and 77 Br decay. The parent nulcides were produced in ISOLDE on line isotope separator at CERN. The efficiency calibration method used for energies higher than 200 keV made use of the well known beta spectrum of 36 Cl. The calibration for low energies was made with Auger electron intensities and suitable conversion lines of 129 Xenon. Results for relative intensities of conversion electron lines and intense gamma lines of 129 Xe and 77 Se are given. From these measurements internal conversion coefficients for transitions of both nuclides were obtained. The results were in agreement with theoretical calculations. (author)
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Payam Amini
2017-09-01
Full Text Available Background: The hospital anxiety and depression scale (HADS is a common screening tool designed to measure the level of anxiety and depression in different factor structures and has been extensively used in non-psychiatric populations and individuals experiencing fertility problems. Objective: The aims of this study were to evaluate the factor structure, item analyses, and internal consistency of HADS in Iranian infertile patients. Materials and Methods: This cross-sectional study included 651 infertile patients (248 men and 403 women referred to a referral infertility Center in Tehran, Iran between January 2014 and January 2015. Confirmatory factor analysis was used to determine the underlying factor structure of the HADS among one, two, and threefactor models. Several goodness of fit indices were utilized such as comparative, normed and goodness of fit indices, Akaike information criterion, and the root mean squared error of approximation. In addition to HADS, the Satisfaction with Life Scale questionnaires as well as demographic and clinical information were administered to all patients. Results: The goodness of fit indices through CFAs exposed that three and onefactor model provided the best and worst fit to the total, male and female datasets compared to the other factor structure models for the infertile patients. The Cronbach’s alpha for anxiety and depression subscales were 0.866 and 0.753 respectively. The HADS subscales significantly correlated with SWLS, indicating an acceptable convergent validity. Conclusion: The HADS was found to be a three-factor structure screening instrument in the field of infertility.
International Nuclear Information System (INIS)
Malmberg, T.
1993-09-01
The objective of this study is to derive and investigate thermodynamic restrictions for a particular class of internal variable models. Their evolution equations consist of two contributions: the usual irreversible part, depending only on the present state, and a reversible but path dependent part, linear in the rates of the external variables (evolution equations of ''mixed type''). In the first instance the thermodynamic analysis is based on the classical Clausius-Duhem entropy inequality and the Coleman-Noll argument. The analysis is restricted to infinitesimal strains and rotations. The results are specialized and transferred to a general class of elastic-viscoplastic material models. Subsequently, they are applied to several viscoplastic models of ''mixed type'', proposed or discussed in the literature (Robinson et al., Krempl et al., Freed et al.), and it is shown that some of these models are thermodynamically inconsistent. The study is closed with the evaluation of the extended Clausius-Duhem entropy inequality (concept of Mueller) where the entropy flux is governed by an assumed constitutive equation in its own right; also the constraining balance equations are explicitly accounted for by the method of Lagrange multipliers (Liu's approach). This analysis is done for a viscoplastic material model with evolution equations of the ''mixed type''. It is shown that this approach is much more involved than the evaluation of the classical Clausius-Duhem entropy inequality with the Coleman-Noll argument. (orig.) [de
Barreto, Rodrigo Py Gonçalves; Barbosa, Marcus Levi Lopes; Balbinotti, Marcos Alencar Abaide; Mothes, Fernando Carlos; da Rosa, Luís Henrique Telles; Silva, Marcelo Faria
2016-01-01
To translate and culturally adapt the CMS and assess the validity of the Brazilian version (CMS-BR). The translation was carried out according to the back-translation method by four independent translators. The produced versions were synthesized through extensive analysis and by consensus of an expert committee, reaching a final version used for the cultural adaptation. A field test was conducted with 30 subjects in order to obtain semantic considerations. For the psychometric analyzes, the sample was increased to 110 participants who answered two instruments: CMS-BR and the Disabilities of the Arm, shoulder and Hand (DASH). The CMS-BR and DASH score range from 0 to 100 points. For the first, higher points reflect better function and for the latter, the inverse is true. The validity was verified by Pearson's correlation test, the unidimensionality by factorial analysis, and the internal consistency by Cronbach's alpha. The explained variance was 60.28% with factor loadings ranging from 0.60 to 0.91. The CMS-BR exhibited strong negative correlation with the DASH score (-0.82, p CMS was satisfactorily adapted for Brazilian Portuguese and demonstrated evidence of validity that allows its use in this population.
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Beyer, Christopher; Rosenthal, Anja; Myhill, Robert; Crichton, Wilson A.; Yu, Tony; Wang, Yanbin; Frost, Daniel J.
2018-02-01
We have performed an experimental cross calibration of a suite of mineral equilibria within mantle rock bulk compositions that are commonly used in geobarometry to determine the equilibration depths of upper mantle assemblages. Multiple barometers were compared simultaneously in experimental runs, where the pressure was determined using in-situ measurements of the unit cell volumes of MgO, NaCl, Re and h-BN between 3.6 and 10.4 GPa, and 1250 and 1500 °C. The experiments were performed in a large volume press (LVPs) in combination with synchrotron X-ray diffraction. Noble metal capsules drilled with multiple sample chambers were loaded with a range of bulk compositions representative of peridotite, eclogite and pyroxenite lithologies. By this approach, we simultaneously calibrated the geobarometers applicable to different mantle lithologies under identical and well determined pressure and temperature conditions. We identified discrepancies between the calculated and experimental pressures for which we propose simple linear or constant correction factors to some of the previously published barometric equations. As a result, we establish internally-consistent cross-calibrations for a number of garnet-orthopyroxene, garnet-clinopyroxene, Ca-Tschermaks-in-clinopyroxene and majorite geobarometers.
Noel, Valerie A; Francis, Sarah E; Tilley, Micah A
2018-04-01
Parent-youth and peer relationship inventories based on attachment theory measure communication, trust, and alienation, yet sibling relationships have been overlooked. We developed the Sibling Attachment Inventory and evaluated its psychometric properties in a sample of 172 youth ages 10-14 years. We adapted the 25-item Sibling Attachment Inventory from the Inventory of Parent and Peer Attachment-Revised peer measure. Items loaded onto three factors, identified as communication, trust, and alienation, α = 0.93, 0.90, and 0.76, respectively. Sibling trust and alienation correlated with depression (r s = -0.33, r s = 0.48) and self-worth (r s = 0.23; r s = -0.32); sibling trust and alienation correlated with depression after controlling for parent trust and parent alienation (r s = -0.23, r s = 0.22). Preliminary analyses showed good internal consistency, construct validity, and incremental predictive validity. Following replication of these properties, this measure can facilitate large cohort assessments of sibling attachment.
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Akinpelu Aderonke O
2008-10-01
Full Text Available Abstract Background The Ibadan Knee/Hip Osteoarthritis Outcome Measure (IKHOAM was developed for measuring end results of care in patients with knee or hip OA in Nigeria. The purpose of this study was to validate a Hausa translation of IKHOAM in order to promote its use among the Hausa populations of Nigeria and other West African countries. Methods Sixty-seven patients with knee OA, literate in Hausa and English, recruited consecutively from all government hospitals in Kano were assessed on both English and Hausa versions of IKHOAM. The order of assessment with the versions was randomized and separated by 24 hours. Participants also rated their pain intensity on the Visual Analogue Scale. Data was analyzed using the Spearman Rank Order correlation and Cronbach's alpha. Results The participants (17 males, 50 females were aged 55.7 ± 13.4 years. Participants' scores on the Hausa version correlated significantly with the original version (r = 0.67, p = 0.000 and with pain intensity scores on the Visual Analogue Scale (r = -0.24, p = 0.005. The Cronbach's alpha for correlation on the different parts of the Hausa version ranged between 0.28 and 0.95. Conclusion The Hausa version of IKHOAM meets the criteria for validity and internal consistency and may be used in the Hausa speaking parts of Nigeria and other West African countries.
Internally consistent thermodynamic data for aqueous species in the system Na-K-Al-Si-O-H-Cl
Miron, George D.; Wagner, Thomas; Kulik, Dmitrii A.; Heinrich, Christoph A.
2016-08-01
A large amount of critically evaluated experimental data on mineral solubility, covering the entire Na-K-Al-Si-O-H-Cl system over wide ranges in temperature and pressure, was used to simultaneously refine the standard state Gibbs energies of aqueous ions and complexes in the framework of the revised Helgeson-Kirkham-Flowers equation of state. The thermodynamic properties of the solubility-controlling minerals were adopted from the internally consistent dataset of Holland and Powell (2002; Thermocalc dataset ds55). The global optimization of Gibbs energies of aqueous species, performed with the GEMSFITS code (Miron et al., 2015), was set up in such a way that the association equilibria for ion pairs and complexes, independently derived from conductance and potentiometric data, are always maintained. This was achieved by introducing reaction constraints into the parameter optimization that adjust Gibbs energies of complexes by their respective Gibbs energy effects of reaction, whenever the Gibbs energies of reactant species (ions) are changed. The optimized thermodynamic dataset is reported with confidence intervals for all parameters evaluated by Monte Carlo trial calculations. The new thermodynamic dataset is shown to reproduce all available fluid-mineral phase equilibria and mineral solubility data with good accuracy and precision over wide ranges in temperature (25-800 °C), pressure (1 bar to 5 kbar) and composition (salt concentrations up to 5 molal). The global data optimization process adopted in this study can be readily repeated any time when extensions to new chemical elements and species are needed, when new experimental data become available, or when a different aqueous activity model or equation of state should be used. This work serves as a proof of concept that our optimization strategy is feasible and successful in generating a thermodynamic dataset reproducing all fluid-mineral and aqueous speciation equilibria in the Na-K-Al-Si-O-H-Cl system within
Directory of Open Access Journals (Sweden)
M. Chahoud
2017-06-01
Conclusion: The results of our analyses reveal that both English and French versions of the ISI scale have good internal consistency and are reproducible and reliable. Therefore, it can be used to assess the prevalence of insomnia in Lebanese adolescents.
MCGUCKIN, CONOR
2006-01-01
PUBLISHED The Oxford Happiness Questionnaire short-form is a recently developed eight-item measure of happiness. This study evaluated the internal consistency reliability and test-retest reliability of the Oxford Happiness Questionnaire short-form among 55 Northern Irish undergraduate university students who completed the measure on two occasions separated by two weeks. Internal consistency of the measure on both occasions was satisfactory at both Time 1 (alpha = .62) and Time 2 (alpha = ....
DEFF Research Database (Denmark)
Christiansen, Jens; Klit, Peder; Vølund, Anders
2007-01-01
engine. The basic idea is to use the fluid film damping coefficients to estimate the film thickness variation for a piston ring under cyclic varying load. Reynolds Equation is solved for a piston ring and the oil film thickness is determined. In this analysis hydrodynamic lubrication is assumed......In 1966 Jorgen W. Lund published an approach to find the dynamic coefficients of a journal bearing by a first order perturbation of the Reynold's equation. These coefficients made it possible to perform a rotor-bearing stability analysis for a statically loaded bearing. In the mid seventies Jorgen...
International Nuclear Information System (INIS)
Tian, Lixin; Ding, Zhenqi; Zhen, Zaili; Wang, Minggang
2016-01-01
The international crude oil market plays a crucial role in economies, and the studies of the correlation, risk and synchronization of the international crude oil market have important implications for the security and stability of the country, avoidance of business risk and people's daily lives. We investigate the information and characteristics of the international crude oil market (1999-2015) based on the random matrix theory (RMT). Firstly, we identify richer information in the largest eigenvalues deviating from RMT predictions for the international crude oil market; the international crude oil market can be roughly divided into ten different periods by the methods of eigenvectors and characteristic combination, and the implied market information of the correlation coefficient matrix is advanced. Secondly, we study the characteristics of the international crude oil market by the methods of system risk entropy, dynamic synchronous ratio, dynamic non-synchronous ratio and dynamic clustering algorithm. The results show that the international crude oil market is full of risk. The synchronization of the international crude oil market is very strong, and WTI and Brent occupy a very important position in the international crude oil market. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Tian, Lixin [Jiangsu University, Energy Development and Environmental Protection Strategy Research Center, Zhenjiang, Jiangsu (China); Nanjing Normal University, School of Mathematical Sciences, Nanjing, Jiangsu (China); Ding, Zhenqi; Zhen, Zaili [Jiangsu University, Energy Development and Environmental Protection Strategy Research Center, Zhenjiang, Jiangsu (China); Wang, Minggang [Nanjing Normal University, School of Mathematical Sciences, Nanjing, Jiangsu (China)
2016-08-15
The international crude oil market plays a crucial role in economies, and the studies of the correlation, risk and synchronization of the international crude oil market have important implications for the security and stability of the country, avoidance of business risk and people's daily lives. We investigate the information and characteristics of the international crude oil market (1999-2015) based on the random matrix theory (RMT). Firstly, we identify richer information in the largest eigenvalues deviating from RMT predictions for the international crude oil market; the international crude oil market can be roughly divided into ten different periods by the methods of eigenvectors and characteristic combination, and the implied market information of the correlation coefficient matrix is advanced. Secondly, we study the characteristics of the international crude oil market by the methods of system risk entropy, dynamic synchronous ratio, dynamic non-synchronous ratio and dynamic clustering algorithm. The results show that the international crude oil market is full of risk. The synchronization of the international crude oil market is very strong, and WTI and Brent occupy a very important position in the international crude oil market. (orig.)
Vujanovic, Anka A.; Arrindell, Willem A.; Bernstein, Amit; Norton, Peter J.; Zvolensky, Michael J.
The present investigation examined the factor structure, internal consistency, and construct validity of the 16-item Anxiety Sensitivity Index (ASI; Reiss Peterson, Gursky, & McNally 1986) in a young adult sample (n = 420)from the Netherlands. Confirmatory factor analysis was used to comparatively
Hale, S. J.; Chaplin, W. J.; Davies, G. R.; Elsworth, Y. P.; Howe, R.; Lund, M. N.; Moxon, E. Z.; Thomas, A.; Pallé, P. L.; Rhodes, E. J., Jr.
2017-09-01
Over 30 years of solar data have been acquired by the Birmingham Solar Oscillations Network (BiSON), an international network of telescopes used to study oscillations of the Sun. Five of the six BiSON telescopes are located at major observatories. The observational sites are, in order of increasing longitude: Mount Wilson (Hale) Observatory (MWO), California, USA; Las Campanas Observatory, Chile; Observatorio del Teide, Izaña, Tenerife, Canary Islands; the South African Astronomical Observatory, Sutherland, South Africa; Carnarvon, Western Australia; and the Paul Wild Observatory, Narrabri, New South Wales, Australia. The BiSON data may be used to measure atmospheric extinction coefficients in the {{{I}}}{{c}} band (approximately 700-900 nm), and presented here are the derived atmospheric extinction coefficients from each site over the years 1984-2016.
Hylla, Jonas; Schwab, Christian G G; Isfort, Michael; Halek, Margareta; Dichter, Martin N
2016-07-01
Background: The maintenance and promotion of Quality of Life (QoL) of people with dementia is a major outcome in intervention studies and health care. The Quality of Life Alzheimer's Disease (QoL-AD) is an internationally recommended QoL measurement also available in German language. Until now, only a few results on the psychometric properties of the German QoL-AD were available. Objective: Evaluation of internal consistency and construct validity of the QoL-AD proxy. Method: A principal component analysis (secondary data analysis) of the 13 QoL-AD items was carried out based on the total sample of 234 people with dementia from nine nursing homes in Germany. Subsequently, the internal consistency of the identified factors was examined using Cronbach's alpha. Results: Two factors physical and mental health and social network were determined. Both factors explain 53 % of the total variance. The stability of both factors was validated in two sensitivity analyses. The internal consistency is good for both factors with a Cronbach's alpha of 0.88 (physical and mental health) and 0.75 (social network). Conclusion: The QoL-AD proxy allows the assessment of two relevant health-related QoL domains of people with dementia. However, in future studies especially the inter-rater reliability of the QoL-AD proxy has to be examined.
McKay, Michael T; Andretta, James R
2017-09-01
Mental well-being is an important indicator of current, but also the future health of adolescents. The 14-item Warwick Edinburgh Mental Well-being Scale (WEMWBS) has been well validated in adults world-wide, but less work has been undertaken to examine the psychometric validity and internal consistency of WEMWBS scores in adolescents. In particular, little research has examined scores on the short 7-item version of the WEMWBS. The present study used two large samples of school children in Scotland and Northern Ireland and found that for both forms of the WEMWBS, scores were psychometrically valid, internally consistent, factor saturated, and measurement invariant by country. Using the WEMWBS full form, males reported significantly higher scores than females, and Northern Irish adolescents reported significantly higher scores than their Scottish counterparts. Last, the lowest overall levels of well-being were observed among Scottish females. Copyright © 2017. Published by Elsevier B.V.
Azar Sabet; Akram Azad; Ghorban Taghizadeh
2016-01-01
Objectives: This study was performed to evaluate convergent validity, test-retest reliability and internal consistency of the Persian translation of the Fullerton advanced balance (FAB) for use in Iranian community- dwelling older adults and improve the quality of their functional balance assessment. Methods & Materials: The original scale was translated with forward-backward protocol. In the next step, using convenience sampling and inclusion criteria, 88 functionally indep...
Robbins, Mandy; Francis, Leslie J.; Edwards, Bethan
2010-01-01
The Oxford Happiness Questionnaire (OHQ) was developed by Hills and Argyle (2002) to provide a more accessible equivalent measure of the Oxford Happiness Inventory (OHI). The aim of the present study was to examine the internal consistency reliability, and construct validity of this new instrument alongside the Eysenckian dimensional model of personality. The Oxford Happiness Questionnaire was completed by a sample of 131 undergraduate students together with the abbreviated form of the Revise...
Riquelme, Arnoldo; Herrera, Cristian; Aranis, Carolina; Oporto, Jorge; Padilla, Oslando
2009-06-01
The Spanish version of the Postgraduate Hospital Educational Environment Measure (PHEEM) was evaluated in this study to determine its psychometric properties, validity and internal consistency to measure the clinical learning environment in the hospital setting of Pontificia Universidad Católica de Chile Medical School's Internship. The 40-item PHEEM questionnaire was translated from English to Spanish and retranslated to English. Content validity was tested by a focus group and minor differences in meaning were adjusted. The PHEEM was administered to clerks in years 6 and 7. Construct validity was carried out using exploratory factor analysis followed by a Varimax rotation. Internal consistency was measured using Cronbach's alpha. A total of 125 out of 220 students responded to the PHEEM. The overall response rate was 56.8% and compliances with each item ranged from 99.2% to 100%. Analyses indicate that five factors instrument accounting for 58% of the variance and internal consistency of the 40-item questionnaire is 0.955 (Cronbach's alpha). The 40-item questionnaire had a mean score of 98.21 +/- 21.2 (maximum score of 160). The Spanish version of PHEEM is a multidimensional, valid and highly reliable instrument measuring the educational environment among undergraduate medical students working in hospital-based clerkships.
Directory of Open Access Journals (Sweden)
Yasmira CARRILLO-BERNATE
Full Text Available ABSTRACT Objective To assess internal consistency and content validity of a questionnaire aimed to assess the stages of Behavioural Lifestyle Changes in a sample of school-aged children and adolescents aged 9 to 17 years-old. Methods This validation study involved 675 schoolchildren from three official school in the city of Bogota, Colombia. A self-administered questionnaire called Behavioural Lifestyle Changes has been designed to explore stages of change regarding to physical activity/exercise, fruit and vegetable consumption, alcohol abuse, tobacco use, and drug abuse. Cronbach-α, Kappa index and exploratory factor analysis were used for evaluating the internal consistency and validity of content, respectively. Results The study population consisted of 51.1% males and the participants’ average age was 12.7±2.4 years-old. Behavioural Lifestyle Changes scored 0.720 (range 0.691 to 0.730 on the Cronbach α and intra-observer reproducibility was good (Kappa=0.71. Exploratory factor analysis determined two factors (factor 1: physical activity/exercise, fruit and vegetable consumption, and factor 2: alcohol abuse tobacco use and drug abuse, explaining 67.78% of variance by the items and six interactions χ2/gL=11649.833; p<0.001. Conclusion Behavioural Lifestyle Changes Questionnaire was seen to have suitable internal consistency and validity. This instrument can be recommended, mainly within the context of primary attention for studying the stages involved in the lifestyle behavioural changes model on a school-based population.
Mor, Vincent; Intrator, Orna; Unruh, Mark Aaron; Cai, Shubing
2011-04-15
The Minimum Data Set (MDS) for nursing home resident assessment has been required in all U.S. nursing homes since 1990 and has been universally computerized since 1998. Initially intended to structure clinical care planning, uses of the MDS expanded to include policy applications such as case-mix reimbursement, quality monitoring and research. The purpose of this paper is to summarize a series of analyses examining the internal consistency and predictive validity of the MDS data as used in the "real world" in all U.S. nursing homes between 1999 and 2007. We used person level linked MDS and Medicare denominator and all institutional claim files including inpatient (hospital and skilled nursing facilities) for all Medicare fee-for-service beneficiaries entering U.S. nursing homes during the period 1999 to 2007. We calculated the sensitivity and positive predictive value (PPV) of diagnoses taken from Medicare hospital claims and from the MDS among all new admissions from hospitals to nursing homes and the internal consistency (alpha reliability) of pairs of items within the MDS that logically should be related. We also tested the internal consistency of commonly used MDS based multi-item scales and examined the predictive validity of an MDS based severity measure viz. one year survival. Finally, we examined the correspondence of the MDS discharge record to hospitalizations and deaths seen in Medicare claims, and the completeness of MDS assessments upon skilled nursing facility (SNF) admission. Each year there were some 800,000 new admissions directly from hospital to US nursing homes and some 900,000 uninterrupted SNF stays. Comparing Medicare enrollment records and claims with MDS records revealed reasonably good correspondence that improved over time (by 2006 only 3% of deaths had no MDS discharge record, only 5% of SNF stays had no MDS, but over 20% of MDS discharges indicating hospitalization had no associated Medicare claim). The PPV and sensitivity levels of
DEFF Research Database (Denmark)
Staunstrup, Jørgen
1998-01-01
This paper proposes that Interface Consistency is an important issue for the development of modular designs. Byproviding a precise specification of component interfaces it becomes possible to check that separately developedcomponents use a common interface in a coherent matter thus avoiding a very...... significant source of design errors. Awide range of interface specifications are possible, the simplest form is a syntactical check of parameter types.However, today it is possible to do more sophisticated forms involving semantic checks....
Directory of Open Access Journals (Sweden)
Sharmila Vaz
Full Text Available The social skills rating system (SSRS is used to assess social skills and competence in children and adolescents. While its characteristics based on United States samples (US are published, corresponding Australian figures are unavailable. Using a 4-week retest design, we examined the internal consistency, retest reliability and measurement error (ME of the SSRS secondary student form (SSF in a sample of Year 7 students (N = 187, from five randomly selected public schools in Perth, western Australia. Internal consistency (IC of the total scale and most subscale scores (except empathy on the frequency rating scale was adequate to permit independent use. On the importance rating scale, most IC estimates for girls fell below the benchmark. Test-retest estimates of the total scale and subscales were insufficient to permit reliable use. ME of the total scale score (frequency rating for boys was equivalent to the US estimate, while that for girls was lower than the US error. ME of the total scale score (importance rating was larger than the error using the frequency rating scale. The study finding supports the idea of using multiple informants (e.g. teacher and parent reports, not just student as recommended in the manual. Future research needs to substantiate the clinical meaningfulness of the MEs calculated in this study by corroborating them against the respective Minimum Clinically Important Difference (MCID.
Vaz, Sharmila; Parsons, Richard; Passmore, Anne Elizabeth; Andreou, Pantelis; Falkmer, Torbjörn
2013-01-01
The social skills rating system (SSRS) is used to assess social skills and competence in children and adolescents. While its characteristics based on United States samples (US) are published, corresponding Australian figures are unavailable. Using a 4-week retest design, we examined the internal consistency, retest reliability and measurement error (ME) of the SSRS secondary student form (SSF) in a sample of Year 7 students (N = 187), from five randomly selected public schools in Perth, western Australia. Internal consistency (IC) of the total scale and most subscale scores (except empathy) on the frequency rating scale was adequate to permit independent use. On the importance rating scale, most IC estimates for girls fell below the benchmark. Test-retest estimates of the total scale and subscales were insufficient to permit reliable use. ME of the total scale score (frequency rating) for boys was equivalent to the US estimate, while that for girls was lower than the US error. ME of the total scale score (importance rating) was larger than the error using the frequency rating scale. The study finding supports the idea of using multiple informants (e.g. teacher and parent reports), not just student as recommended in the manual. Future research needs to substantiate the clinical meaningfulness of the MEs calculated in this study by corroborating them against the respective Minimum Clinically Important Difference (MCID).
Osório, Flávia de Lima; Crippa, José Alexandre S; Loureiro, Sonia Regina
2009-03-01
The objective of the present study was to carry out the cross- cultural validation for Brazilian Portuguese of the Social Phobia Inventory, an instrument for the evaluation of fear, avoidance and physiological symptoms associated with social anxiety disorder. The process of translation and adaptation involved four bilingual professionals, appreciation and approval of the back- translation by the authors of the original scale, a pilot study with 30 Brazilian university students, and appreciation by raters who confirmed the face validity of the Portuguese version, which was named ' Inventário de Fobia Social' . As part of the psychometric study of the Social Phobia Inventory, analysis of the items and evaluation of the internal consistency of the instrument were performed in a study conducted on 2314 university students. The results demonstrated that item 11, related to the fear of public speaking, was the most frequently scored item. The correlation of the items with the total score was quite adequate, ranging from 0.44 to 0.71, as was the internal consistency, which ranged from 0.71 to 0.90. The authors conclude that the Brazilian Portuguese version of the Social Phobia Inventory proved to be adequate regarding the psychometric properties initially studied, with qualities quite close to those of the original study. Studies that will evaluate the remaining indicators of validity of the Social Phobia Inventory in clinical and non-clinical samples are considered to be opportune and necessary.
Lang, Jonas W B
2014-07-01
The measurement of implicit or unconscious motives using the picture story exercise (PSE) has long been a target of debate in the psychological literature. Most debates have centered on the apparent paradox that PSE measures of implicit motives typically show low internal consistency reliability on common indices like Cronbach's alpha but nevertheless predict behavioral outcomes. I describe a dynamic Thurstonian item response theory (IRT) model that builds on dynamic system theories of motivation, theorizing on the PSE response process, and recent advancements in Thurstonian IRT modeling of choice data. To assess the models' capability to explain the internal consistency paradox, I first fitted the model to archival data (Gurin, Veroff, & Feld, 1957) and then simulated data based on bias-corrected model estimates from the real data. Simulation results revealed that the average squared correlation reliability for the motives in the Thurstonian IRT model was .74 and that Cronbach's alpha values were similar to the real data (value of extant evidence from motivational research using PSE motive measures. (c) 2014 APA, all rights reserved.
Estimating varying coefficients for partial differential equation models.
Zhang, Xinyu; Cao, Jiguo; Carroll, Raymond J
2017-09-01
Partial differential equations (PDEs) are used to model complex dynamical systems in multiple dimensions, and their parameters often have important scientific interpretations. In some applications, PDE parameters are not constant but can change depending on the values of covariates, a feature that we call varying coefficients. We propose a parameter cascading method to estimate varying coefficients in PDE models from noisy data. Our estimates of the varying coefficients are shown to be consistent and asymptotically normally distributed. The performance of our method is evaluated by a simulation study and by an empirical study estimating three varying coefficients in a PDE model arising from LIDAR data. © 2017, The International Biometric Society.
Konzelmann, M; Burrus, C; Hilfiker, R; Rivier, G; Deriaz, O; Luthi, F
2015-03-01
Functional evaluation of upper limb is not only based on clinical findings but requires self-administered questionnaires to address patients' perspective. The Hand Function Sort (HFS©) was only validated in English. The aim of this study was the French cross cultural adaptation and validation of the HFS© (HFS-F). 150 patients with various upper limbs impairments were recruited in a rehabilitation center. Translation and cross-cultural adaptation were made according to international guidelines. Construct validity was estimated through correlations with Disabilities Arm Shoulder and Hand (DASH) questionnaire, SF-36 mental component summary (MCS),SF-36 physical component summary (PCS) and pain intensity. Internal consistency was assessed by Cronbach's α and test-retest reliability by intraclass correlation. Cronbach's α was 0.98, test-retest reliability was excellent at 0.921 (95 % CI 0.871-0.971) same as original HFS©. Correlations with DASH were-0.779 (95 % CI -0.847 to -0.685); with SF 36 PCS 0.452 (95 % CI 0.276-0.599); with pain -0.247 (95 % CI -0.429 to -0.041); with SF 36 MCS 0.242 (95 % CI 0.042-0.422). There were no floor or ceiling effects. The HFS-F has the same good psychometric properties as the original HFS© (internal consistency, test retest reliability, convergent validity with DASH, divergent validity with SF-36 MCS, and no floor or ceiling effects). The convergent validity with SF-36 PCS was poor; we found no correlation with pain. The HFS-F could be used with confidence in a population of working patients. Other studies are necessary to study its psychometric properties in other populations.
Directory of Open Access Journals (Sweden)
Vitor Tumas
2004-12-01
Full Text Available We evaluated the reliability of a translated Brazilian version of the Unified Huntington's Disease Rating Scale (UHDRS to establish the reproducibility of the scale in a population that differs substantially from that on which the scale was originally validated. After a training period with the video and guidelines requested from the Huntington Study Group, we applied the UHDRS, except for the cognitive tests, to a group of 21 Brazilian patients with a molecular diagnosis of Huntington's disease (HD. We found a high degree of internal consistency of the motor section of the UHDRS (Cronbach's alpha= 0.841. There was a negative correlation between the total motor score and the functional assessment, the independence scale and the functional capacity. There was a positive correlation between these 3 scales of functional evaluation and a negative correlation between the age of onset of the disease and the number of CAG repeats. The behavioral scale and disease duration were not correlated with any factor. The clinical characteristics of this sample of patients as described by the UHDRS were roughly similar to those reported in the original validation studies and the correlations described were similar to those reported previously. We conclude that the Brazilian version of the UHDRS is reliable and valid to study patients with HD in the Brazilian setting, that this sample of Brazilian patients had clinical characteristics similar to those observed in other world regions, as expected, and that the clinical training method used for the application of the UHDRS was effective to insure a high degree of clinical reproducibility.Nosso estudo avaliou a confiabilidade da versão brasileira da escala unificada para avaliação da doença de Huntington (UHDRS com o objetivo de estabelecer a reprodutibilidade dessa escala em uma população que difere significativamente daquela em que foi originalmente validada. Após um período de treinamento com um v
Directory of Open Access Journals (Sweden)
Rubén Ledesma
2002-12-01
Full Text Available En este trabajo se presenta una herramienta informática original que permite realizar análisis de consistencia interna (modelo Alfa de Cronbach utilizando métodos gráficos dinámicos. Se trata de un módulo basado en la filosofía del Análisis Exploratorio de Datos y en métodos de visualización estadística, diseñado para asistir al analista en el proceso de construcción de pruebas psicológicas. La herramienta permite analizar la consistencia interna de la prueba, las propiedades de los ítems que la componen, los patrones de respuesta de los sujetos a los ítems, y el efecto de la eliminación de los ítems y del incremento en la longitud de la prueba sobre su fiabilidad. En comparación con otros programas existentes, el beneficio del módulo es la incorporación de gráficos estadísticos dinámicos como complemento a la presentación de resultados convencionales en formato texto.This paper describes a computer software that provides dynamic graphics to perform internal consistence analysis by means of Cronbach’s Alpha. This software, based on Exploratory Data Analysis philosophy and statistical visualization methods, is designed to assist the process of psychological test and scale construction. It allows carry out internal consistency analysis, as well as exploring statistical properties of items, subject responses patterns, and the effect of item deletion and test length increase on reliability coefficient. Comparing with other statistical software, the benefit of this program is to use dynamic graphics complementing statistical output.
Calibration factor or calibration coefficient?
International Nuclear Information System (INIS)
Meghzifene, A.; Shortt, K.R.
2002-01-01
Full text: The IAEA/WHO network of SSDLs was set up in order to establish links between SSDL members and the international measurement system. At the end of 2001, there were 73 network members in 63 Member States. The SSDL network members provide calibration services to end-users at the national or regional level. The results of the calibrations are summarized in a document called calibration report or calibration certificate. The IAEA has been using the term calibration certificate and will continue using the same terminology. The most important information in a calibration certificate is a list of calibration factors and their related uncertainties that apply to the calibrated instrument for the well-defined irradiation and ambient conditions. The IAEA has recently decided to change the term calibration factor to calibration coefficient, to be fully in line with ISO [ISO 31-0], which recommends the use of the term coefficient when it links two quantities A and B (equation 1) that have different dimensions. The term factor should only be used for k when it is used to link the terms A and B that have the same dimensions A=k.B. However, in a typical calibration, an ion chamber is calibrated in terms of a physical quantity such as air kerma, dose to water, ambient dose equivalent, etc. If the chamber is calibrated together with its electrometer, then the calibration refers to the physical quantity to be measured per electrometer unit reading. In this case, the terms referred have different dimensions. The adoption by the Agency of the term coefficient to express the results of calibrations is consistent with the 'International vocabulary of basic and general terms in metrology' prepared jointly by the BIPM, IEC, ISO, OIML and other organizations. The BIPM has changed from factor to coefficient. The authors believe that this is more than just a matter of semantics and recommend that the SSDL network members adopt this change in terminology. (author)
de Almeida Vieira Monteiro, Ana Paula Teixeira; Fernandes, Alexandre Bastos
2016-05-17
Cultural competence is an essential component in rendering effective and culturally responsive services to culturally and ethnically diverse clients. Still, great difficulty exists in assessing the cultural competence of mental health nurses. There are no Portuguese validated measurement instruments to assess cultural competence in mental health nurses. This paper reports a study testing the reliability and validity of the Portuguese version of the Multicultural Mental Health Awareness Scale-MMHAS in a sample of Portuguese nurses. Following a standard forward/backward translation into Portuguese, the adapted version of MMHAS, along with a sociodemographic questionnaire, were applied to a sample of 306 Portuguese nurses (299 males, 77 females; ages 21-68 years, M = 35.43, SD = 9.85 years). A psychometric research design was used with content and construct validity and reliability. Reliability was assessed using internal consistency and item-total correlations. Construct validity was determined using factor analysis. The factor analysis confirmed that the Portuguese version of MMHAS has a three-factor structure of multicultural competencies (Awareness, Knowledge, and Skills) explaining 59.51% of the total variance. Strong content validity and reliability correlations were demonstrated. The Portuguese version of MMHAS has a strong internal consistency, with a Cronbach's alpha of 0.958 for the total scale. The results supported the construct validity and reliability of the Portuguese version of MMHAS, proving that is a reliable and valid measure of multicultural counselling competencies in mental health nursing. The MMHAS Portuguese version can be used to evaluate the effectiveness of multicultural competency training programs in Portuguese-speaking mental health nurses. The scale can also be a useful in future studies of multicultural competencies in Portuguese-speaking nurses.
Mahieu, Lieslot; de Casterlé, Bernadette Dierckx; Van Elssen, Kim; Gastmans, Chris
2013-11-01
This paper reports a study testing the content and face validity and internal consistency of the Dutch version of the Aging Sexual Knowledge and Attitudes Scale. The ability of older residents to sexually express themselves is known to be influenced by the knowledge and attitudes of nursing home staff towards later-life sexuality. Although the Aging Sexual Knowledge and Attitudes Scale is a widely used instrument to measure this, there is no validated, Dutch translation available. Instrument development. Following a standard forward/backward translation into Dutch, the scale was further adapted for use in Flemish nursing home settings. Content and face validity and user-friendliness were assessed. The psychometric properties were determined by means of an exploratory study. Data were collected from March-April 2011 at eight Flemish nursing homes. Reliability was assessed using internal consistency and item-total correlations. Both subscales of the Flemish adaptation showed acceptable content validity. The face validity and user-friendliness were deemed favourable with hardly any remarks given by the expert panel. The Cronbach's α was 0.80 and 0.88 for the knowledge and attitude subscales, respectively. The item-total correlations ranged from 0.21-0.48 for the knowledge section and from 0.09-0.68 for the attitude subscale. We conclude from our study that the Dutch version of the scale has acceptable to good psychometric properties. The Flemish adaptation therefore seems to be a valuable instrument for studying nursing staff's knowledge and attitudes towards aged sexuality in Flanders. © 2013 Blackwell Publishing Ltd.
The internal consistency of the Test of Variables of Attention (TOVA) was examined in a cohort of 6- to 12-year-old children (N = 63) strictly diagnosed with ADHD. The internal consistency of errors of omission (OMM), errors of commission (COM), response time (RT), and response time variability (RTV...
2017-01-01
Indicators of compliance and efficiency in combatting money laundering, collected by EUROSTAT, are plagued with shortcomings. In this paper, I have carried out a forensic analysis on a 2003–2010 dataset of indicators of compliance and efficiency in combatting money laundering, that European Union member states self-reported to EUROSTAT, and on the basis of which, their efforts were evaluated. I used Benford’s law to detect any anomalous statistical patterns and found that statistical anomalies were also consistent with strategic manipulation. According to Benford’s law, if we pick a random sample of numbers representing natural processes, and look at the distribution of the first digits of these numbers, we see that, contrary to popular belief, digit 1 occurs most often, then digit 2, and so on, with digit 9 occurring in less than 5% of the sample. Without prior knowledge of Benford’s law, since people are not intuitively good at creating truly random numbers, deviations thereof can capture strategic alterations. In order to eliminate other sources of deviation, I have compared deviations in situations where incentives and opportunities for manipulation existed and in situations where they did not. While my results are not a conclusive proof of strategic manipulation, they signal that countries that faced incentives and opportunities to misinform the international community about their efforts to combat money laundering may have manipulated these indicators. Finally, my analysis points to the high potential for disruption that the manipulation of national statistics has, and calls for the acknowledgment that strategic manipulation can be an unintended consequence of the international community’s pressure on countries to put combatting money laundering on the top of their national agenda. PMID:28122058
Possolo, Antonio; Schlamminger, Stephan; Stoudt, Sara; Pratt, Jon R.; Williams, Carl J.
2018-02-01
The Consultative Committee for Mass and related quantities (CCM), of the International Committee for weights and measures (CIPM), has recently declared the readiness of the community to support the redefinition of the international system of units (SI) at the next meeting of the General Conference on Weights and Measures (CGPM) scheduled for November, 2018. Such redefinition will replace the international prototype of the Kilogram (IPK), as the definition and sole primary realization of the unit of mass, with a definition involving the Planck constant, h. This redefinition in terms of a fundamental constant of nature will enable widespread primary realizations not only of the kilogram but also of its multiples and sub-multiples, best to address the full range of practical needs in the measurement of mass. We review and discuss the statistical models and statistical data reductions, uncertainty evaluations, and substantive arguments that support the verification of several technical preconditions for the redefinition that the CCM has established, and whose verification the CCM has affirmed. These conditions relate to the accuracy and mutual consistency of qualifying measurement results. We review also an issue that has surfaced only recently, concerning the convergence toward a stable value, of the historical values that the task group on fundamental constants of the committee on Data for Science and Technology CODATA-TGFC has recommended for h over the years, even though the CCM has not deemed this issue to be relevant. We conclude that no statistically significant trend can be substantiated for these recommended values, but note that cumulative consensus values that may be derived from the historical measurement results for h seem to have converged while continuing to exhibit fluctuations that are typical of a process in statistical control. Finally, we argue that the most recent consensus value derived from the best measurements available for h, obtained using
Directory of Open Access Journals (Sweden)
Mauro B Terra
2006-12-01
Full Text Available OBJECTIVE: Liebowitz Social Anxiety Scale is an instrument used to evaluate the severity of social phobia. It has been widely used in different contexts and cultures, presenting variable psychometric properties. The objective of this article is to investigate the internal consistency and the factor structure of this scale. METHOD: In a sample of 300 alcoholic patients hospitalized in 3 mental clinics in Southern Brazil, 74 of them were social phobics (24.6%. The Structured Clinical Interview for DSM-IV-Axis I Disorders - Patient Edition, a semi-structured clinical interview based on DSM-IV, was used to check for the diagnosis of social phobia. The internal consistency was measured by Cronbach's alpha. Data were subjected to a factor analysis with the principal component method of parameter estimation. Questionnaire items loading at 0.35 or above were considered in the final factor solution. RESULTS: The coefficient of internal consistency was 0.95. All items showed corrected item-total correlation coefficient above 0.15, considered the minimum requested index. The factor analysis resulted in 5 dimensions which corresponded to 52.9% of the total variance. The five factors extracted were: factor I - speaking in a group, factor II - activity in public, factor III - social interaction with unknown person, factor IV - attitude of disagreement or disapproval and factor V - social interaction in leisure activity. CONCLUSIONS: The scale proved to be reliable and structurally valid instrument for use in a population of alcoholic patients. The possibility of screening for social phobia through the use of the instrument may be helpful in identifying probable cases of the disorder among alcoholics.OBJETIVO: A Escala de Ansiedade Social de Liebowitz é um instrumento utilizado na avaliação da gravidade da fobia social. Tem sido amplamente usada em diferentes contextos e culturas, apresentando propriedades psicométricas variadas. O objetivo do artigo
Assessment of the Maximal Split-Half Coefficient to Estimate Reliability
Thompson, Barry L.; Green, Samuel B.; Yang, Yanyun
2010-01-01
The maximal split-half coefficient is computed by calculating all possible split-half reliability estimates for a scale and then choosing the maximal value as the reliability estimate. Osburn compared the maximal split-half coefficient with 10 other internal consistency estimates of reliability and concluded that it yielded the most consistently…
Coefficient alpha and interculture test selection.
Thurber, Steven; Kishi, Yasuhiro
2014-04-01
The internal consistency reliability of a measure can be a focal point in an evaluation of the potential adequacy of an instrument for adaptation to another cultural setting. Cronbach's alpha (α) coefficient is often used as the statistical index for such a determination. However, alpha presumes a tau-equivalent test and may constitute an inaccurate population estimate for multidimensional tests. These notions are expanded and examined with a Japanese version of a questionnaire on nursing attitudes toward suicidal patients, originally constructed in Sweden using the English language. The English measure was reported to have acceptable internal consistency (α) albeit the dimensionality of the questionnaire was not addressed. The Japanese scale was found to lack tau-equivalence. An alternative to alpha, "composite reliability," was computed and found to be below acceptable standards in magnitude and precision. Implications for research application of the Japanese instrument are discussed. © The Author(s) 2012.
Mail, Abdul; Pratikto; Suparman, Sudjito; Purnomo; Santoso, Budi
2014-01-01
The study aims to find out the influence of internal quality process on the growth of quality culture in private college. This study is treated toward 178 lecturers of 25 private colleges in Sulawesi, Indonesia by means of questionnaire. Confirmatory factor analysis applied to assess the reliability of validity and measurement model. Relationship…
Pailian, Hrag; Halberda, Justin
2015-04-01
We investigated the psychometric properties of the one-shot change detection task for estimating visual working memory (VWM) storage capacity-and also introduced and tested an alternative flicker change detection task for estimating these limits. In three experiments, we found that the one-shot whole-display task returns estimates of VWM storage capacity (K) that are unreliable across set sizes-suggesting that the whole-display task is measuring different things at different set sizes. In two additional experiments, we found that the one-shot single-probe variant shows improvements in the reliability and consistency of K estimates. In another additional experiment, we found that a one-shot whole-display-with-click task (requiring target localization) also showed improvements in reliability and consistency. The latter results suggest that the one-shot task can return reliable and consistent estimates of VWM storage capacity (K), and they highlight the possibility that the requirement to localize the changed target is what engenders this enhancement. Through a final series of four experiments, we introduced and tested an alternative flicker change detection method that also requires the observer to localize the changing target and that generates, from response times, an estimate of VWM storage capacity (K). We found that estimates of K from the flicker task correlated with estimates from the traditional one-shot task and also had high reliability and consistency. We highlight the flicker method's ability to estimate executive functions as well as VWM storage capacity, and discuss the potential for measuring multiple abilities with the one-shot and flicker tasks.
Serfon, Cedric; The ATLAS collaboration
2016-01-01
One of the biggest challenge with Large scale data management system is to ensure the consistency between the global file catalog and what is physically on all storage elements. To tackle this issue, the Rucio software which is used by the ATLAS Distributed Data Management system has been extended to automatically handle lost or unregistered files (aka Dark Data). This system automatically detects these inconsistencies and take actions like recovery or deletion of unneeded files in a central manner. In this talk, we will present this system, explain the internals and give some results.
International Nuclear Information System (INIS)
Kanazu, Tsutomu
1998-01-01
When a reinforced concrete member is exposed to high temperature conditions over 100degC, tensile strain occurs in the concrete and compressive strain occurs in reinforcements due to a difference of thermal expansion coefficients between concrete and reinforcement. Its mechanism is the same as that of restrained stress caused by drying shrinkage of concrete; tensile stress occurs in the concrete because drying shrinkage strain is restrained by reinforcements, but there is a different point that the phenomenon at a high temperature condition includes the change of mechanical properties of concrete and reinforcement. In the study, the phenomenon is measured in the experiments and is clarified quantitatively. Moreover, the estimation method, which is derived from expanding the equation of average strain of reinforcement in the CEB Design Manual, is suggested and is verified by the comparison with the experimental results. (author)
Energy Technology Data Exchange (ETDEWEB)
Venkateswara Rao, N.; Suryanarayana, C.; Narayana, D.G.S.; Bhuloka Reddy, S.; Satynarayana, G.; Sastry, D.L.; Chintalapudi, S.N.
1986-02-21
The 1.87 hours 543.7 keV (7/sup +/) isomeric state in /sup 198/Tl is produced via /sup 197/Au(..cap alpha.., 3n)sup(198m)Tl (Esub(..cap alpha..) = 35 MeV) reaction. The total conversion coefficient of 260.9 keV (7/sup +/ -> 3/sup -/) is determined for the first time by the intensity balance method. The value of ..cap alpha..sub(T)(260.9 keV) is found to be 40.1 +- 8.6 which is in good agreement with the theoretical value of Hager and Seltzer for pure M4 transition. The gamma transition probability of the 260.9 keV (M4) is calculated using the present value of ..cap alpha..sub(T) and compared with the single-particle estimate.
Directory of Open Access Journals (Sweden)
Melgar-Quinonez Hugo
2008-05-01
Full Text Available Abstract Objective We assessed the validity of a locally adapted Colombian Household Food Security Scale (CHFSS used as a part of the 2006 evaluation of the food supplement component of the Plan for Improving Food and Nutrition in Antioquia, Colombia (MANA – Plan Departamental de Seguridad Alimentaria y Nutricional de Antioquia. Methods Subjects included low-income families with pre-school age children in MANA that responded affirmatively to at least one CHFSS item (n = 1,319. Rasch Modeling was used to evaluate the psychometric characteristics of the items through measure and INFIT values. Differences in CHFSS performance were assessed by area of residency, socioeconomic status and number of children enrolled in MANA. Unidimensionality of a scale by group was further assessed using Differential Item Functioning (DIF. Results Most CHFSS items presented good fitness with most INFIT values within the adequate range of 0.8 to 1.2. Consistency in item measure values between groups was found for all but two items in the comparison by area of residency. Only two adult items exhibited DIF between urban and rural households. Conclusion The results indicate that the adapted CHFSS is a valid tool to assess the household food security of participants in food assistance programs like MANA.
Hackett, Michelle; Melgar-Quinonez, Hugo; Uribe, Martha C Alvarez
2008-05-23
We assessed the validity of a locally adapted Colombian Household Food Security Scale (CHFSS) used as a part of the 2006 evaluation of the food supplement component of the Plan for Improving Food and Nutrition in Antioquia, Colombia (MANA - Plan Departamental de Seguridad Alimentaria y Nutricional de Antioquia). Subjects included low-income families with pre-school age children in MANA that responded affirmatively to at least one CHFSS item (n = 1,319). Rasch Modeling was used to evaluate the psychometric characteristics of the items through measure and INFIT values. Differences in CHFSS performance were assessed by area of residency, socioeconomic status and number of children enrolled in MANA. Unidimensionality of a scale by group was further assessed using Differential Item Functioning (DIF). Most CHFSS items presented good fitness with most INFIT values within the adequate range of 0.8 to 1.2. Consistency in item measure values between groups was found for all but two items in the comparison by area of residency. Only two adult items exhibited DIF between urban and rural households. The results indicate that the adapted CHFSS is a valid tool to assess the household food security of participants in food assistance programs like MANA.
Structural Consistency, Consistency, and Sequential Rationality.
Kreps, David M; Ramey, Garey
1987-01-01
Sequential equilibria comprise consistent beliefs and a sequentially ra tional strategy profile. Consistent beliefs are limits of Bayes ratio nal beliefs for sequences of strategies that approach the equilibrium strategy. Beliefs are structurally consistent if they are rationaliz ed by some single conjecture concerning opponents' strategies. Consis tent beliefs are not necessarily structurally consistent, notwithstan ding a claim by Kreps and Robert Wilson (1982). Moreover, the spirit of stru...
Buntragulpoontawee, Montana; Phutrit, Suphatha; Tongprasert, Siam; Wongpakaran, Tinakon; Khunachiva, Jeeranan
2018-03-27
This study evaluated additional psychometric properties of the Thai version of the disabilities of the arm, shoulder and hand questionnaire (DASH-TH) which included, test-retest reliability, construct validity, internal consistency of in patients with carpal tunnel syndrome. As for determining construct validity, the Thai EuroQOL questionnaire (EQ-5D-5L) was also administered in order to examine convergent and divergent validity. Fifty patients completed both questionnaires. The DASH-TH showed excellent test-retest reliability (intraclass correlation coefficient = 0.811) and internal consistency (Cronbach's alpha = 0.911). The exploratory factor analysis yielded a six-factor solution while the confirmatory factor analysis denoted that the hypothesized model adequately fit the data with a comparative fit index of 0.967 and a Tucker-Lewis index of 0.964. The related subscales between the DASH-TH and the Thai EQ-5D-5L were significantly correlated, indicating the DASH-TH's convergent and discriminant validity. The DASH-TH demonstrated good reliability, internal consistency construct validity, and multidimensionality, in assessing the upper extremity function in carpal tunnel syndrome patients.
International Nuclear Information System (INIS)
Wang Xiaomin; Tegmark, Max; Zaldarriaga, Matias
2002-01-01
We perform a detailed analysis of the latest cosmic microwave background (CMB) measurements (including BOOMERaNG, DASI, Maxima and CBI), both alone and jointly with other cosmological data sets involving, e.g., galaxy clustering and the Lyman Alpha Forest. We first address the question of whether the CMB data are internally consistent once calibration and beam uncertainties are taken into account, performing a series of statistical tests. With a few minor caveats, our answer is yes, and we compress all data into a single set of 24 bandpowers with associated covariance matrix and window functions. We then compute joint constraints on the 11 parameters of the 'standard' adiabatic inflationary cosmological model. Our best fit model passes a series of physical consistency checks and agrees with essentially all currently available cosmological data. In addition to sharp constraints on the cosmic matter budget in good agreement with those of the BOOMERaNG, DASI and Maxima teams, we obtain a heaviest neutrino mass range 0.04-4.2 eV and the sharpest constraints to date on gravity waves which (together with preference for a slight red-tilt) favor 'small-field' inflation models
Directory of Open Access Journals (Sweden)
Ana Carolina Soares Amaral
2011-08-01
Full Text Available O objetivo do estudo foi descrever o processo de adaptação transcultural do Sociocultural Attitudes Towards Appearance Questionnaire-3 (SATAQ-3 para a língua portuguesa. A metodologia foi baseada nas etapas de (1 tradução do questionário para o português; (2 retrotradução para o inglês; (3 comitê de peritos para construção da primeira versão; (4 avaliação da compreensão verbal por especialistas e por uma amostra da população-alvo; (5 análise da consistência interna do instrumento a partir do alfa de Cronbach. O instrumento foi traduzido para o português e a versão final contou com os 30 itens do instrumento original. Todos os itens foram interpretados como de fácil compreensão, tanto por especialistas quanto pela população-alvo. Os valores de consistência interna foram satisfatórios, sendo de 0,91 para toda a escala. O instrumento encontra-se traduzido e adaptado para o português, com evidências de boa compreensão e consistência interna, sendo ainda necessária a avaliação de sua equivalência de mensuração, validade externa e reprodutibilidade.This study aimed to describe the cross-cultural adaptation of the Sociocultural Attitudes Towards Appearance Questionnaire-3 (SATAQ-3 into Brazilian Portuguese. The methodology involved the following stages: (1 translation of the questionnaire into Portuguese; (2 back-translation into English; (3 meeting with experts to prepare a draft version; (4 assessment of verbal understanding of the draft by experts and by a sample of the target population; and (5 analysis of the tool's internal consistency, using Cronbach's alpha. The questionnaire was translated into Portuguese, and the scale's final version included 30 items, as in the original. Both the experts and target population members assessed all the items as easy to understand. Internal consistency was satisfactory, reaching 0.91 for the scale as a whole. The questionnaire has now been translated and adapted into
Consistency of Teacher-Reported Problems for Students in 21 Countries
Rescorla, Leslie A.; Achenbach, Thomas M.; Ginzburg, Sofia; Ivanova, Masha; Dumenci, Levent; Almqvist, Fredrik; Bathiche, Marie; Bilenberg, Niels; Bird, Hector; Domuta, Anca; Erol, Nese; Fombonne, Eric; Fonseca, Antonio; Frigerio, Alessandra; Kanbayashi, Yasuko; Lambert, Michael C.; Liu, Xianchen; Leung, Patrick; Minaei, Asghar; Roussos, Alexandra; Simsek, Zeynep; Weintraub, Sheila; Weisz, John; Wolanczyk, Tomasz; Zubrick, Stephen R.; Zukauskiene, Rita; Verhulst, Frank
2007-01-01
This study compared teachers' ratings of behavioral and emotional problems on the Teacher's Report Form for general population samples in 21 countries (N = 30,957). Correlations between internal consistency coefficients in different countries averaged 0.90. Effects of country on scale scores ranged from 3% to 13%. Gender effects ranged from less…
Directory of Open Access Journals (Sweden)
Patrícia Picon
2006-01-01
Full Text Available OBJECTIVE: Theoretical and empirical analysis of items and internal consistency of the Portuguese-language version of Social Phobia and Anxiety Inventory (SPAI-Portuguese. METHODS: Social phobia experts conducted a 45-item content analysis of the SPAI-Portuguese administered to a sample of 1,014 university students. Item discrimination was evaluated by Student's t test; interitem, mean and item-to-total correlations, by Pearson coefficient; reliability was estimated by Cronbach's alpha. RESULTS: There was 100% agreement among experts concerning the 45 items. On the SPAI-Portuguese 43 items were discriminative (p OBJETIVO: Análise teórica e empírica dos itens e da consistência interna da versão em português do Social Phobia and Anxiety Inventory (SPAI-Português e subescalas. MÉTODOS: Peritos em fobia social conduziram análise de conteúdo dos 45 itens do SPAI-Português, administrado a 1.014 estudantes universitários. A discriminação dos itens foi avaliada por teste t de Student; correlações interitens, médias e item/total por coeficientes de Pearson; fidedignidade pelo alfa de Cronbach. RESULTADOS: Concordância plena entre os peritos para os 45 itens. SPAI-Português com 43 itens discriminativos (p < 0,05. Alguns itens, entre as subescalas, apresentaram coeficientes abaixo de 0,2. As médias das correlações interitens foram: 0,41 na subescala fobia social; 0,32 na subescala agorafobia; e 0,32 no SPAI-Português. As correlações item/total foram maiores do que 0,3 (p < 0,001. Alfas de Cronbach foram: 0,95 no SPAI-Português; 0,96 na subescala de fobia social; 0,85 na subescala de agorafobia. CONCLUSÃO: O conteúdo dos itens foi relacionado aos constructos subjacentes (agorafobia e fobia social, com discriminabilidade de 43 itens do SPAI-Português. As correlações médias interitens e alfas revelaram consistência interna de SPAI-Português e subescalas, além de multidimensionalidade das mesmas. Nenhum item foi suprimido
Rusli, B N; Amrina, K; Trived, S; Loh, K P; Shashi, M
2017-10-01
The 21-item English version of the Depression Anxiety Stress Scale (DASS-21) has been proposed as a method for assessing self-perceived depression, anxiety and stress over the past week in various clinical and nonclinical populations. Several Malay versions of the DASS-21 have been validated in various populations with varying success. One particular Malay version has been validated in various occupational groups (such as nurses and automotive workers) but not among male clinic outpatient attendees in Malaysia. To validate the Malay version of the DASS-21 (Malay-DASS-21) among male outpatient clinic attendees in Johor. A validation study with a random sample of 402 male respondents attending the outpatient clinic of a major public outpatient clinic in Johor Bahru and Segamat was carried out from January to March 2016. Construct validity of the Malay-DASS-21 was examined using Exploratory Factor Analysis (KMO = 0.947; Bartlett's test of sphericity is significant, pDASS- 21 and the internal consistency reliability using Cronbach's alpha. Construct validity of the Malay-DASS-21 based on eigenvalues and factor loadings to confirm the three factor structure (depression, anxiety, and stress) was acceptable. The internal consistency reliability of the factor construct was very impressive with Cronbach's alpha values in the range of 0.837 to 0.863. The present study showed that the Malay- DASS-21 has acceptable psychometric construct and high internal consistency reliability to measure self-perceived depression, anxiety and stress over the past week in male outpatient clinic attendees in Johor. Further studies are necessary to revalidate the Malay-DASS-21 across different populations and cultures, and using confirmatory factor analyses.
Directory of Open Access Journals (Sweden)
Elizângela Moreira Careta Galindo
2007-02-01
Full Text Available Este trabalho tem por objetivo traduzir, adaptar e validar o Eating Behaviours and Body Image Test, para uso com crianças de uma cidade do interior do estado de São Paulo. Foram sujeitos do estudo 261 escolares do sexo feminino, na faixa etária de 9 a 12 anos. Por meio da análise fatorial, com rotação varimax avaliou-se a consistência interna do instrumento. Esta análise, realizada com o auxílio do programa Statistical Package for Social Sciences, versão 10.0, revelou dois fatores. Para o instrumento total a consistência interna foi adequada (coeficiente a de Cronbach: 0,89 e para os dois fatores (1 e 2 os valores de a também foram considerados satisfatórios (alfa=0,90 e alfa=0,80, respectivamente, mostrando, assim, que o Eating Behaviours and Body Image Test é útil para uma avaliação precoce, rastreando atitudes indicadoras de possíveis distúrbios no comportamento alimentar. Foram mantidas as características psicométricas do instrumento original.This study aimed to translate, adapt and validate the Eating Bahaviours and Body Image Test, to be used with children in a city in upstate São Paulo. Study subjects were 261 female students aging from 9 to 12 years. The internal consistency of the instrument was evaluated by means of factorial analysis with varimax rotation. This analysis was accomplished through Statistical Package for Social Sciences, version 10.0, revealing two factors. The internal consistency was adequate for the total instrument (Cronbach's alpha=0.89 and a values were also considered satisfactory for the two factors (1 and 2 (alpha=0.90 and alpha=0.80, respectively, which demonstrated that the Eating Bahaviours and Body Image Test is useful for an initial evaluation, tracing symptoms that indicate possible eating behavior disorders. The psychometric characteristics of the original instrument were maintained.
Lee, Chin-Pang; Chiu, Yu-Wen; Chu, Chun-Lin; Chen, Yu; Jiang, Kun-Hao; Chen, Jiun-Liang; Chen, Ching-Yen
2016-12-01
The aging males' symptoms (AMS) scale is an instrument used to determine the health-related quality of life in adult and elderly men. The purpose of this study was to synthesize internal consistency (Cronbach's alpha) and test-retest reliability for the AMS scale and its three subscales. Of the 123 studies reviewed, 12 provided alpha coefficients which were then used in the meta-analyses of internal consistency. Seven of the 12 included studies provided test-retest coefficients, and these were used in the meta-analyses of test-retest reliability. The AMS scale had excellent internal consistency [α = 0.89 (95% CI 0.88-0.90)]; the mean alpha estimates across the AMS subscales ranged from 0.79 to 0.82. The AMS scale also had good test-retest reliability [r = 0.85 (95% CI 0.82-0.88]; the test-retest reliability coefficients of the AMS subscales ranged from 0.76 to 0.83. There was significant heterogeneity among the included studies. The AMS scale and the three subscales had fairly good internal consistency and test-retest reliability. Future psychometric studies of the AMS scale should report important characteristics of the participants, details of item scores, and test-retest reliability.
Transport Coefficients of Fluids
Eu, Byung Chan
2006-01-01
Until recently the formal statistical mechanical approach offered no practicable method for computing the transport coefficients of liquids, and so most practitioners had to resort to empirical fitting formulas. This has now changed, as demonstrated in this innovative monograph. The author presents and applies new methods based on statistical mechanics for calculating the transport coefficients of simple and complex liquids over wide ranges of density and temperature. These molecular theories enable the transport coefficients to be calculated in terms of equilibrium thermodynamic properties, and the results are shown to account satisfactorily for experimental observations, including even the non-Newtonian behavior of fluids far from equilibrium.
Consistent model driven architecture
Niepostyn, Stanisław J.
2015-09-01
The goal of the MDA is to produce software systems from abstract models in a way where human interaction is restricted to a minimum. These abstract models are based on the UML language. However, the semantics of UML models is defined in a natural language. Subsequently the verification of consistency of these diagrams is needed in order to identify errors in requirements at the early stage of the development process. The verification of consistency is difficult due to a semi-formal nature of UML diagrams. We propose automatic verification of consistency of the series of UML diagrams originating from abstract models implemented with our consistency rules. This Consistent Model Driven Architecture approach enables us to generate automatically complete workflow applications from consistent and complete models developed from abstract models (e.g. Business Context Diagram). Therefore, our method can be used to check practicability (feasibility) of software architecture models.
Fuller, Daniel; Gauvin, Lise; Fournier, Michel; Kestens, Yan; Daniel, Mark; Morency, Patrick; Drouin, Louis
2012-04-01
Active living is a broad conceptualization of physical activity that incorporates domains of exercise; recreational, household, and occupational activities; and active transportation. Policy makers develop and implement a variety of transportation policies that can influence choices about how to travel from one location to another. In making such decisions, policy makers act in part in response to public opinion or support for proposed policies. Measures of the public's support for policies aimed at promoting active transportation can inform researchers and policy makers. This study examined the internal consistency, and concurrent and discriminant validity of a newly developed measure of the public's support for policies for active living in transportation (PAL-T). A series of 17 items representing potential policies for promoting active transportation was generated. Two samples of participants (n = 2,001 and n = 2,502) from Montreal, Canada, were recruited via random digit dialling. Analyses were conducted on the combined data set (n = 4,503). Participants were aged 18 through 94 years (58% female). The concurrent and discriminant validity of the PAL-T was assessed by examining relationships with physical activity and smoking. To explore the usability of the PAL-T, predicted scale scores were compared to the summed values of responses. Results showed that the internal consistency of the PAL-T was 0.70. Multilevel regression demonstrated no relationship between the PAL-T and smoking status (p > 0.05) but significant relationships with utilitarian walking (p public opinion can inform policy makers and support advocacy efforts aimed at making built environments more suitable for active transportation while allowing researchers to examine the antecedents and consequences of public support for policies.
Lacruz, Me; Emeny, Rt; Bickel, H; Linkohr, B; Ladwig, Kh
2013-09-01
Test the feasibility of the modified telephone interview for cognitive status (TICS-m) as a screening tool to detect cognitive impairment in a population-based sample of older subjects. Data were collected from 3,578 participants, age 65-94 years, of the KORA-Age study. We used analysis of covariance to test for significant sex, age and educational differences in raw TICS-m scores. Internal consistency was analysed by assessing Cronbach's alpha. Correction for education years was undertaken, and participants were divided in three subgroups following validated cut-offs. Finally, a logistic regression was performed to determine the impact of sex on cognition subgroups. Internal consistency of the TICS-m was 0.78. Study participants needed approximately 5.4 min to complete the interview. Lower raw TICS-m scores were associated with male sex, older age and lower education (all p education years, 2,851 (79%) had a non-impaired cognitive status (score >31). Male sex was independently associated with having a score equal to or below 27 and 31 (OR = 1.9, 95% CI 1.4-2.5 and OR = 1.5, 95% CI 1.2-1.7, respectively). The TICS-m is a feasible questionnaire for community-dwelling older adults with normal cognitive function or moderate cognitive impairment. Lower cognitive performance was associated with being a man, being older, and having fewer years of formal education. Copyright © 2012 John Wiley & Sons, Ltd.
Bitcoin Meets Strong Consistency
Decker, Christian; Seidel, Jochen; Wattenhofer, Roger
2014-01-01
The Bitcoin system only provides eventual consistency. For everyday life, the time to confirm a Bitcoin transaction is prohibitively slow. In this paper we propose a new system, built on the Bitcoin blockchain, which enables strong consistency. Our system, PeerCensus, acts as a certification authority, manages peer identities in a peer-to-peer network, and ultimately enhances Bitcoin and similar systems with strong consistency. Our extensive analysis shows that PeerCensus is in a secure state...
Consistent classical supergravity theories
International Nuclear Information System (INIS)
Muller, M.
1989-01-01
This book offers a presentation of both conformal and Poincare supergravity. The consistent four-dimensional supergravity theories are classified. The formulae needed for further modelling are included
Directory of Open Access Journals (Sweden)
Flávia de Lima Osório
2009-03-01
Full Text Available OBJECTIVE: The objective of the present study was to carry out the cross- cultural validation for Brazilian Portuguese of the Social Phobia Inventory, an instrument for the evaluation of fear, avoidance and physiological symptoms associated with social anxiety disorder. METHOD: The process of translation and adaptation involved four bilingual professionals, appreciation and approval of the back- translation by the authors of the original scale, a pilot study with 30 Brazilian university students, and appreciation by raters who confirmed the face validity of the Portuguese version, which was named " Inventário de Fobia Social" . As part of the psychometric study of the Social Phobia Inventory, analysis of the items and evaluation of the internal consistency of the instrument were performed in a study conducted on 2314 university students. RESULTS: The results demonstrated that item 11, related to the fear of public speaking, was the most frequently scored item. The correlation of the items with the total score was quite adequate, ranging from 0.44 to 0.71, as was the internal consistency, which ranged from 0.71 to 0.90. DISCUSSION/CONCLUSION: The authors conclude that the Brazilian Portuguese version of the Social Phobia Inventory proved to be adequate regarding the psychometric properties initially studied, with qualities quite close to those of the original study. Studies that will evaluate the remaining indicators of validity of the Social Phobia Inventory in clinical and non-clinical samples are considered to be opportune and necessary.OBJETIVO: O objetivo deste estudo foi realizar a validação transcultural para o português do Brasil do Social Phobia Inventory, um instrumento para avaliação e mensuração dos sintomas de medo, evitação e sintomas fisiológicos associados ao transtorno de ansiedade social. MÉTODO: O processo de tradução e adaptação envolveu quatro profissionais bilingües, apreciação e aprovação da back
Consistent guiding center drift theories
International Nuclear Information System (INIS)
Wimmel, H.K.
1982-04-01
Various guiding-center drift theories are presented that are optimized in respect of consistency. They satisfy exact energy conservation theorems (in time-independent fields), Liouville's theorems, and appropriate power balance equations. A theoretical framework is given that allows direct and exact derivation of associated drift-kinetic equations from the respective guiding-center drift-orbit theories. These drift-kinetic equations are listed. Northrop's non-optimized theory is discussed for reference, and internal consistency relations of G.C. drift theories are presented. (orig.)
Consistent force fields for saccharides
DEFF Research Database (Denmark)
Rasmussen, Kjeld
1999-01-01
Consistent force fields for carbohydrates were hitherto developed by extensive optimization ofpotential energy function parameters on experimental data and on ab initio results. A wide range of experimental data is used: internal structures obtained from gas phase electron diffraction and from x......-anomeric effects are accounted for without addition of specific terms. The work is done in the framework of the Consistent Force Field which originatedin Israel and was further developed in Denmark. The actual methods and strategies employed havebeen described previously. Extensive testing of the force field...
Consistency of orthodox gravity
Energy Technology Data Exchange (ETDEWEB)
Bellucci, S. [INFN, Frascati (Italy). Laboratori Nazionali di Frascati; Shiekh, A. [International Centre for Theoretical Physics, Trieste (Italy)
1997-01-01
A recent proposal for quantizing gravity is investigated for self consistency. The existence of a fixed-point all-order solution is found, corresponding to a consistent quantum gravity. A criterion to unify couplings is suggested, by invoking an application of their argument to more complex systems.
Quasiparticles and thermodynamical consistency
International Nuclear Information System (INIS)
Shanenko, A.A.; Biro, T.S.; Toneev, V.D.
2003-01-01
A brief and simple introduction into the problem of the thermodynamical consistency is given. The thermodynamical consistency relations, which should be taken into account under constructing a quasiparticle model, are found in a general manner from the finite-temperature extension of the Hellmann-Feynman theorem. Restrictions following from these relations are illustrated by simple physical examples. (author)
Implications of NGA for NEHRP site coefficients
Borcherdt, Roger D.
2012-01-01
Three proposals are provided to update tables 11.4-1 and 11.4-2 of Minimum Design Loads for Buildings and Other Structures (7-10), by the American Society of Civil Engineers (2010) (ASCE/SEI 7-10), with site coefficients implied directly by NGA (Next Generation Attenuation) ground motion prediction equations (GMPEs). Proposals include a recommendation to use straight-line interpolation to infer site coefficients at intermediate values of ̅vs (average shear velocity). Site coefficients are recommended to ensure consistency with ASCE/SEI 7-10 MCER (Maximum Considered Earthquake) seismic-design maps and simplified site-specific design spectra procedures requiring site classes with associated tabulated site coefficients and a reference site class with unity site coefficients. Recommended site coefficients are confirmed by independent observations of average site amplification coefficients inferred with respect to an average ground condition consistent with that used for the MCER maps. The NGA coefficients recommended for consideration are implied directly by the NGA GMPEs and do not require introduction of additional models.
Nuclear data for the calculation of thermal reactor reactivity coefficients
International Nuclear Information System (INIS)
1989-01-01
On its 15th meeting in Vienna, 16-20 June 1986, the International Nuclear Data Committee (INDC) considered it important to review the accuracy with which changes in thermal reactor reactivity resulting from changes in temperature and coolant density can be predicted. It was noted that reactor physicists in several countries had to adjust the thermal neutron cross-section data base in order to reproduce measured reactivity coefficients. Consequently, it appeared to be essential to examine the consistency of the integral and differential cross-section data and to make all the information available which has a bearing on reactivity coefficient prediction. Following the recommendation of the INDC, the Nuclear Data Section of the International Atomic Energy Agency, therefore, convened the Advisory Group Meeting on Nuclear Data for the Calculation of Thermal Reaction Reactivity Coefficients, in Vienna, Austria, 7-10 Dec. 1987. The Conclusions and Recommendations of the meeting together with the papers presented, are submitted in the present document. A separate abstract was prepared for each of these 12 papers. Refs, figs and tabs
Bergantiños, Gustavo; Valencia-Toledo, Alfredo; Vidal-Puga, Juan
2016-01-01
The program evaluation review technique (PERT) is a tool used to schedule and coordinate activities in a complex project. In assigning the cost of a potential delay, we characterize the Shapley rule as the only rule that satisfies consistency and other desirable properties.
Gaur, Sonia; Harmon, Stephanie; Rosenblum, Lauren; Greer, Matthew D; Mehralivand, Sherif; Coskun, Mehmet; Merino, Maria J; Wood, Bradford J; Shih, Joanna H; Pinto, Peter A; Choyke, Peter L; Turkbey, Baris
2018-05-07
The purposes of this study were to assess correlation of apparent diffusion coefficient (ADC) and normalized ADC (ratio of tumor to nontumor tissue) with the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) and updated International Society of Urological Pathology (ISUP) categories and to determine how to optimally use ADC metrics for objective assistance in categorizing lesions within PI-RADSv2 guidelines. In this retrospective study, 100 patients (median age, 62 years; range, 44-75 years; prostate-specific antigen level, 7.18 ng/mL; range, 1.70-84.56 ng/mL) underwent 3-T multiparametric MRI of the prostate with an endorectal coil. Mean ADC was extracted from ROIs based on subsequent prostatectomy specimens. Histopathologic analysis revealed 172 lesions (113 peripheral, 59 transition zone). Two radiologists blinded to histopathologic outcome assigned PI-RADSv2 categories. Kendall tau was used to correlate ADC metrics with PI-RADSv2 and ISUP categories. ROC curves were used to assess the utility of ADC metrics in differentiating each reader's PI-RADSv2 DWI category 4 or 5 assessment in the whole prostate and by zone. ADC metrics negatively correlated with ISUP category in the whole prostate (ADC, τ = -0.21, p = 0.0002; normalized ADC, τ = -0.21, p = 0.0001). Moderate negative correlation was found in expert PI-RADSv2 DWI categories (ADC, τ = -0.34; normalized ADC, τ = -0.31; each p correlate with PI-RADSv2 and ISUP categories and can serve as quantitative metrics to assist with assigning PI-RADSv2 DWI category 4 or 5.
DEFF Research Database (Denmark)
Thomsen, Christa; Nielsen, Anne Ellerup
2006-01-01
This chapter first outlines theory and literature on CSR and Stakeholder Relations focusing on the different perspectives and the contextual and dynamic character of the CSR concept. CSR reporting challenges are discussed and a model of analysis is proposed. Next, our paper presents the results...... of a case study showing that companies use different and not necessarily consistent strategies for reporting on CSR. Finally, the implications for managerial practice are discussed. The chapter concludes by highlighting the value and awareness of the discourse and the discourse types adopted...... in the reporting material. By implementing consistent discourse strategies that interact according to a well-defined pattern or order, it is possible to communicate a strong social commitment on the one hand, and to take into consideration the expectations of the shareholders and the other stakeholders...
Geometrically Consistent Mesh Modification
Bonito, A.
2010-01-01
A new paradigm of adaptivity is to execute refinement, coarsening, and smoothing of meshes on manifolds with incomplete information about their geometry and yet preserve position and curvature accuracy. We refer to this collectively as geometrically consistent (GC) mesh modification. We discuss the concept of discrete GC, show the failure of naive approaches, and propose and analyze a simple algorithm that is GC and accuracy preserving. © 2010 Society for Industrial and Applied Mathematics.
International Nuclear Information System (INIS)
Egorov, Gennadiy I.; Makarov, Dmitriy M.; Kolker, Arkadiy M.
2013-01-01
Highlights: ► Molar isothermal compressions and molar isobaric expansions were evaluated. ► Coefficients of thermal pressure and internal pressure were obtained. ► Concentration dependences of coefficients under study display extremes. ► Temperature and pressure dependences of internal pressure of the mixture were linear. -- Abstract: Molar isothermal compressions, molar isobaric expansions, molar coefficients of thermal pressure, and internal pressure were calculated over the whole concentration range of {water (1) + tert-butanol (2)} mixture at pressures from 0.1 to 100 MPa and temperatures from 278.15 to 323.15 K. It was revealed that the extremes, observed on concentration dependences of molar isothermal compression K T,m and molar isobaric expansion E P,m of the mixture, became more pronounced with pressure growth and temperature lowering. Values of molar thermal pressure coefficients of the mixture sharply rose at compositions with small TBA mole fraction and then decreased practically linearly with the alcohol content increasing. Temperature and pressure dependences of the mixture internal pressure were almost linear, and at low TBA concentrations changed significantly from the dependences of water, tert-butanol and their mixtures at large alcohol content
Attenuation coefficients of soils
International Nuclear Information System (INIS)
Martini, E.; Naziry, M.J.
1989-01-01
As a prerequisite to the interpretation of gamma-spectrometric in situ measurements of activity concentrations of soil radionuclides the attenuation of 60 to 1332 keV gamma radiation by soil samples varying in water content and density has been investigated. A useful empirical equation could be set up to describe the dependence of the mass attenuation coefficient upon photon energy for soil with a mean water content of 10%, with the results comparing well with data in the literature. The mean density of soil in the GDR was estimated at 1.6 g/cm 3 . This value was used to derive the linear attenuation coefficients, their range of variation being 10%. 7 figs., 5 tabs. (author)
International Nuclear Information System (INIS)
Anon.
1997-01-01
This rubric reports on 10 short notes about international economical facts about nuclear power: Electricite de France (EdF) and its assistance and management contracts with Eastern Europe countries (Poland, Hungary, Bulgaria); Transnuclear Inc. company (a 100% Cogema daughter company) acquired the US Vectra Technologies company; the construction of the Khumo nuclear power plant in Northern Korea plays in favour of the reconciliation between Northern and Southern Korea; the delivery of two VVER 1000 Russian reactors to China; the enforcement of the cooperation agreement between Euratom and Argentina; Japan requested for the financing of a Russian fast breeder reactor; Russia has planned to sell a floating barge-type nuclear power plant to Indonesia; the control of the Swedish reactor vessels of Sydkraft AB company committed to Tractebel (Belgium); the renewal of the nuclear cooperation agreement between Swiss and USA; the call for bids from the Turkish TEAS electric power company for the building of the Akkuyu nuclear power plant answered by three candidates: Atomic Energy of Canada Limited (AECL), Westinghouse (US) and the French-German NPI company. (J.S.)
Griffiths, Robert B.
2001-11-01
Quantum mechanics is one of the most fundamental yet difficult subjects in physics. Nonrelativistic quantum theory is presented here in a clear and systematic fashion, integrating Born's probabilistic interpretation with Schrödinger dynamics. Basic quantum principles are illustrated with simple examples requiring no mathematics beyond linear algebra and elementary probability theory. The quantum measurement process is consistently analyzed using fundamental quantum principles without referring to measurement. These same principles are used to resolve several of the paradoxes that have long perplexed physicists, including the double slit and Schrödinger's cat. The consistent histories formalism used here was first introduced by the author, and extended by M. Gell-Mann, J. Hartle and R. Omnès. Essential for researchers yet accessible to advanced undergraduate students in physics, chemistry, mathematics, and computer science, this book is supplementary to standard textbooks. It will also be of interest to physicists and philosophers working on the foundations of quantum mechanics. Comprehensive account Written by one of the main figures in the field Paperback edition of successful work on philosophy of quantum mechanics
The Truth About Ballistic Coefficients
Courtney, Michael; Courtney, Amy
2007-01-01
The ballistic coefficient of a bullet describes how it slows in flight due to air resistance. This article presents experimental determinations of ballistic coefficients showing that the majority of bullets tested have their previously published ballistic coefficients exaggerated from 5-25% by the bullet manufacturers. These exaggerated ballistic coefficients lead to inaccurate predictions of long range bullet drop, retained energy and wind drift.
Bayesian Meta-Analysis of Coefficient Alpha
Brannick, Michael T.; Zhang, Nanhua
2013-01-01
The current paper describes and illustrates a Bayesian approach to the meta-analysis of coefficient alpha. Alpha is the most commonly used estimate of the reliability or consistency (freedom from measurement error) for educational and psychological measures. The conventional approach to meta-analysis uses inverse variance weights to combine…
Absorption coefficient instrument for turbid natural waters
Friedman, E.; Cherdak, A.; Poole, L.; Houghton, W.
1980-01-01
The paper presents an instrument that directly measures multispectral absorption coefficient of turbid natural water. Attention is given to the design, which is shown to incorporate methods for the compensation of variation in the internal light source intensity, correction of the spectrally dependent nature of the optical elements, and correction for variation in the background light level. In addition, when used in conjunction with a spectrally matched total attenuation instrument, the spectrally dependent scattering coefficient can also be derived. Finally, it is reported that systematic errors associated with multiple scattering have been estimated using Monte Carlo techniques.
On the Kendall Correlation Coefficient
Stepanov, Alexei
2015-01-01
In the present paper, we first discuss the Kendall rank correlation coefficient. In continuous case, we define the Kendall rank correlation coefficient in terms of the concomitants of order statistics, find the expected value of the Kendall rank correlation coefficient and show that the later is free of n. We also prove that in continuous case the Kendall correlation coefficient converges in probability to its expected value. We then propose to consider the expected value of the Kendall rank ...
Assessing Reliability of a Multi-Dimensional Scale by Coefficient Alpha
Directory of Open Access Journals (Sweden)
Ivan Šerbetar
2016-04-01
Full Text Available The purpose of the study was to assess internal consistency by calculating coefficient alpha. It presents the variation in coefficient alpha, depending on questionnaire length and the homogeneity or heterogeneity of the questionnaire. The maximum possible value for coefficient alpha was also calculated by the item elimination method. The study included 99 children aged 10. The children completed The Athletic Coping Skills Inventory – 28 (ACSI-28; Smith et al., 1995, which contains seven constructs: coping with adversity, coachability, concentration, confidence and achievement motivation, goal setting and mental preparation, peaking under pressure and freedom from worry. The results confirmed that the values of the alpha coefficient vary depending on the number and composition of items and the sample size. In terms of item structure, homogeneous constructs yielded lower values for the alpha coefficient (in a range from .48 to .61 than the questionnaire with all the constructs (alpha = .79, despite higher inter-item correlations. In terms of the number of items, the longer test generated higher alpha coefficients (alpha = .79 than the shorter test (half-sets of items = .60, .73, .69, .70. A higher overall value (alpha = .83 can be achieved by item elimination.
Pinevich, Alexander V
2015-03-01
This taxonomic note was motivated by the recent proposal [Oren & Garrity (2014) Int J Syst Evol Microbiol 64, 309-310] to exclude the oxygenic photosynthetic bacteria (cyanobacteria) from the wording of General Consideration 5 of the International Code of Nomenclature of Prokaryotes (ICNP), which entails unilateral coverage of these prokaryotes by the International Code of Nomenclature for algae, fungi, and plants (ICN; formerly the International Code of Botanical Nomenclature, ICBN). On the basis of key viewpoints, approaches and rules in the systematics, taxonomy and nomenclature of prokaryotes it is reciprocally proposed to apply the ICNP to names of cyanobacteria including those validly published under the ICBN/ICN. For this purpose, a change to Principle 2 of the ICNP is proposed to enable validation of cyanobacterial names published under the ICBN/ICN rules. © 2015 IUMS.
Transfer of risk coefficients across populations
International Nuclear Information System (INIS)
Rasmussen, L.R.
1992-01-01
The variation of lifetime risk projections for a Canadian population caused by the uncertainty in the choice of method for transferring excess relative risk coefficients between populations is assessed. Site-specific projections, varied by factors up to 3.5 when excess risk coefficients of the BEIR V relative risk models were transferred to the Canadian population using an additive and multiplicative method. When the risk from all cancers are combined, differences between transfer methods were no longer significant. The Canadian projections were consistent with the ICRP-60 nominal fatal cancer risk estimates. (author)
Analytic posteriors for Pearson's correlation coefficient.
Ly, Alexander; Marsman, Maarten; Wagenmakers, Eric-Jan
2018-02-01
Pearson's correlation is one of the most common measures of linear dependence. Recently, Bernardo (11th International Workshop on Objective Bayes Methodology, 2015) introduced a flexible class of priors to study this measure in a Bayesian setting. For this large class of priors, we show that the (marginal) posterior for Pearson's correlation coefficient and all of the posterior moments are analytic. Our results are available in the open-source software package JASP.
Analytic posteriors for Pearson's correlation coefficient
Ly, A.; Marsman, M.; Wagenmakers, E.-J.
2018-01-01
Pearson's correlation is one of the most common measures of linear dependence. Recently, Bernardo (11th International Workshop on Objective Bayes Methodology, 2015) introduced a flexible class of priors to study this measure in a Bayesian setting. For this large class of priors, we show that the (marginal) posterior for Pearson's correlation coefficient and all of the posterior moments are analytic. Our results are available in the open‐source software package JASP.
Frictional coefficient depending on active friction radius with BPV ...
African Journals Online (AJOL)
Frictional coefficient depending on active friction radius with BPV and BTV in automobile disc braking system. ... International Journal of Engineering, Science and Technology. Journal Home · ABOUT ... AJOL African Journals Online. HOW TO ...
Temporal correlation coefficient for directed networks.
Büttner, Kathrin; Salau, Jennifer; Krieter, Joachim
2016-01-01
Previous studies dealing with network theory focused mainly on the static aggregation of edges over specific time window lengths. Thus, most of the dynamic information gets lost. To assess the quality of such a static aggregation the temporal correlation coefficient can be calculated. It measures the overall possibility for an edge to persist between two consecutive snapshots. Up to now, this measure is only defined for undirected networks. Therefore, we introduce the adaption of the temporal correlation coefficient to directed networks. This new methodology enables the distinction between ingoing and outgoing edges. Besides a small example network presenting the single calculation steps, we also calculated the proposed measurements for a real pig trade network to emphasize the importance of considering the edge direction. The farm types at the beginning of the pork supply chain showed clearly higher values for the outgoing temporal correlation coefficient compared to the farm types at the end of the pork supply chain. These farm types showed higher values for the ingoing temporal correlation coefficient. The temporal correlation coefficient is a valuable tool to understand the structural dynamics of these systems, as it assesses the consistency of the edge configuration. The adaption of this measure for directed networks may help to preserve meaningful additional information about the investigated network that might get lost if the edge directions are ignored.
Radionuclides distribution coefficient of soil to soil-solution
International Nuclear Information System (INIS)
1990-06-01
The present book addresses various issues related with the coefficient of radionuclides distribution between soil and soil solution. It consists of six sections and two appendices. The second section, following an introductory one, describes the definition of the coefficient and a procedures of its calculation. The third section deals with the application of the distribution coefficient to the prediction of movements of radionuclides through soil. Various methods for measuring the coefficient are described in the fourth section. The next section discusses a variety of factors (physical and chemical) that can affect the distribution coefficient. Measurements of the coefficient for different types of oils are listed in the sixth section. An appendix is attached to the book to show various models that can be helpful in applying the coefficient of distribution of radionuclides moving from soil into agricultural plants. (N.K.)
Energy Technology Data Exchange (ETDEWEB)
Abe, Satoshi, E-mail: abe.satoshi@jaea.go.jp; Ishigaki, Masahiro; Sibamoto, Yasuteru; Yonomoto, Taisuke
2015-08-15
Highlights: . • The third international benchmark exercise (IBE-3) focused on density stratification erosion by a vertical buoyant jet in the reactor containment vessel. • Two types turbulence model modification were applied in order to accurately simulate the turbulence helium transportation in the density stratification. • The analysis result in case with turbulence model modification is good agreement with the experimental data. • There is a major difference of turbulence helium–mass transportation between in case with and without the turbulence model modification. - Abstract: Density stratification in the reactor containment vessel is an important phenomenon on an issue of hydrogen safety. The Japan Atomic Energy Agency (JAEA) has started the ROSA-SA project on containment thermal hydraulics. As a part of the activity, we participated in the third international CFD benchmark exercise (IBE-3) focused on density stratification erosion by a vertical buoyant jet in containment vessel. This paper shows our approach for the IBE-3, focusing on the turbulence transport phenomena in eroding the density stratification and introducing modified turbulence models for improvement of the CFD analyses. For this analysis, we modified the CFD code OpenFOAM by using two turbulence models; the Kato and Launder modification to estimate turbulent kinetic energy production around a stagnation point, and the Katsuki model to consider turbulence damping in density stratification. As a result, the modified code predicted well the experimental data. The importance of turbulence transport modeling is also discussed using the calculation results.
International Nuclear Information System (INIS)
Abe, Satoshi; Ishigaki, Masahiro; Sibamoto, Yasuteru; Yonomoto, Taisuke
2015-01-01
Highlights: . • The third international benchmark exercise (IBE-3) focused on density stratification erosion by a vertical buoyant jet in the reactor containment vessel. • Two types turbulence model modification were applied in order to accurately simulate the turbulence helium transportation in the density stratification. • The analysis result in case with turbulence model modification is good agreement with the experimental data. • There is a major difference of turbulence helium–mass transportation between in case with and without the turbulence model modification. - Abstract: Density stratification in the reactor containment vessel is an important phenomenon on an issue of hydrogen safety. The Japan Atomic Energy Agency (JAEA) has started the ROSA-SA project on containment thermal hydraulics. As a part of the activity, we participated in the third international CFD benchmark exercise (IBE-3) focused on density stratification erosion by a vertical buoyant jet in containment vessel. This paper shows our approach for the IBE-3, focusing on the turbulence transport phenomena in eroding the density stratification and introducing modified turbulence models for improvement of the CFD analyses. For this analysis, we modified the CFD code OpenFOAM by using two turbulence models; the Kato and Launder modification to estimate turbulent kinetic energy production around a stagnation point, and the Katsuki model to consider turbulence damping in density stratification. As a result, the modified code predicted well the experimental data. The importance of turbulence transport modeling is also discussed using the calculation results
Quadrature formulas for Fourier coefficients
Bojanov, Borislav
2009-09-01
We consider quadrature formulas of high degree of precision for the computation of the Fourier coefficients in expansions of functions with respect to a system of orthogonal polynomials. In particular, we show the uniqueness of a multiple node formula for the Fourier-Tchebycheff coefficients given by Micchelli and Sharma and construct new Gaussian formulas for the Fourier coefficients of a function, based on the values of the function and its derivatives. © 2009 Elsevier B.V. All rights reserved.
Activity coefficients of electrons and holes in semiconductors
International Nuclear Information System (INIS)
Orazem, M.E.; Newman, J.
1984-01-01
Dilute-solution transport equations with constant activity coefficients are commonly used to model semiconductors. These equations are consistent with a Boltzmann distribution and are invalid in regions where the species concentration is close to the respective site concentration. A more rigorous treatment of transport in a semiconductor requires activity coefficients which are functions of concentration. Expressions are presented for activity coefficients of electrons and holes in semiconductors for which conduction- and valence-band energy levels are given by the respective bandedge energy levels. These activity coefficients are functions of concentration and are thermodynamically consistent. The use of activity coefficients in macroscopic transport relationships allows a description of electron transport in a manner consistent with the Fermi-Dirac distribution
Coefficient Alpha: A Reliability Coefficient for the 21st Century?
Yang, Yanyun; Green, Samuel B.
2011-01-01
Coefficient alpha is almost universally applied to assess reliability of scales in psychology. We argue that researchers should consider alternatives to coefficient alpha. Our preference is for structural equation modeling (SEM) estimates of reliability because they are informative and allow for an empirical evaluation of the assumptions…
Coefficient estimates of negative powers and inverse coefficients for ...
Indian Academy of Sciences (India)
and the inequality is sharp for the inverse of the Koebe function k(z) = z/(1 − z)2. An alternative approach to the inverse coefficient problem for functions in the class S has been investigated by Schaeffer and Spencer [27] and FitzGerald [6]. Although, the inverse coefficient problem for the class S has been completely solved ...
Measuring of heat transfer coefficient
DEFF Research Database (Denmark)
Henningsen, Poul; Lindegren, Maria
Subtask 3.4 Measuring of heat transfer coefficient Subtask 3.4.1 Design and setting up of tests to measure heat transfer coefficient Objective: Complementary testing methods together with the relevant experimental equipment are to be designed by the two partners involved in order to measure...... the heat transfer coefficient for a wide range of interface conditions in hot and warm forging processes. Subtask 3.4.2 Measurement of heat transfer coefficient The objective of subtask 3.4.2 is to determine heat transfer values for different interface conditions reflecting those typically operating in hot...
International Nuclear Information System (INIS)
Torvanger, A.
1990-11-01
In this paper the reduction in energy-related manufacturing carbon dioxide emissions for nine OECD countries in the period 1973 to 1987 is analyzed. Carbon dioxide emissions are estimated from energy use data. The emphasis is on carbon dioxide intensities, defined as emissions divided by value added. The overall manufacturing carbon dioxide intensity for the nine OECD countries was reduced by 42% in the period 1973--1987. Five fuels are specified together with six subsectors of manufacturing. Carbon dioxide emissions are estimated from fossil fuel consumption, employing emissions coefficients for gas, oil and solids. In addition, electricity consumption is specified. For electricity use an emission coefficient index is calculated from the shares of fossil fuels, nuclear power and hydro power used to generate electricity, and the efficiency in electricity generation from these energy sources. A Divisia index approach is used to sort out the contribution to reduced carbon dioxide intensity from different components. The major finding is that the main contribution to reduced carbon dioxide intensity is from the general reduction in manufacturing energy intensity, most likely driven by economic growth and increased energy prices, giving incentives to invest in new technology and new industrial processes. There is also a significant contribution from reduced production in the most carbon dioxide intensive subsectors, and a contribution from higher efficiency in electricity generation together with a larger nuclear power share at the expense of oil. 19 refs., 5 figs., 11 tabs
Classification of coefficients of variation in experiments with commercial layers
Directory of Open Access Journals (Sweden)
DE Faria Filho
2010-12-01
Full Text Available This study aimed at determining a specific classification of coefficients of variation in experiments with commercial layers. Coefficients of variation were collected from papers published in Brazilian journals between 2000 and 2009 for performance, internal egg quality, and eggshell quality parameters. The coefficients of variation of each parameter were classified as low, intermediate, high, and very high according to the ratio between the median and the pseudo-sigma. It was concluded that the parameters used in experiments with commercial layers have a specific classification of coefficients of variation, and that this must be considered to evaluate experimental accuracy.
Directory of Open Access Journals (Sweden)
Marco Antônio Pereira Teixeira
2008-03-01
Full Text Available O objetivo deste estudo foi construir um instrumento para avaliar seis dimensões de interesses vocacionais: realista (R, ivestigativa, atística (A, social (S, empreendedora (E e cnvencional (C. Os itens gerados foram aplicados a estudantes de ensino médio e universitários, totalizando 857 protocolos válidos. Análises de componentes principais foram conduzidas para selecionar os melhores itens. Obteve-se uma solução de seis componentes, compatível com as expectativas teóricas, com 48 itens (8 por dimensão. A consistência interna (alpha de Cronbach obtida para cada uma das escalas foi: R (0,83, I (0,79, A (0,78, S (0,85, E (0,74 e C (0,80. Análises das subamostras de estudantes universitários e de ensino médio feitas separadamente produziram resultados similares. Comparações específicas entre pares contrastantes de cursos universitários revelaram a capacidade das escalas para discriminar grupos-critério; portanto, há evidências de que o instrumento proposto é válido e fidedigno, podendo ser utilizado em futuras pesquisas.El objetivo de este estudio fue el construir un instrumento para avaluar seis dimensiones de intereses vocacionales: Realista (R, Investigativo (I, Artístico (A, Social (S, Emprendedor (E y Convencional (C. Los ítemes generados fueron aplicados a estudiantes de secundaria y universitarios, totalizando 857 protocolos válidos. Análisis de componentes principales fueron conducidos para seleccionar los mejores ítemes. Se obtuvo una solución de seis componentes compatible con las expectativas teóricas con 48 ítemes (8 por dimensión. La consistencia interna (alpha de Cronbach obtenida para cada una de las escalas fue: R (0,83, I (0,79, A (0,78, S (0,85, E (0,74 y C (0,80. Análisis de las submuestras de estudiantes universitarios y de secundaria, por separado, produjeron resultados similares. Comparaciones específicas entre pares contrastantes de cursos universitarios revelaron la capacidad de las
Developing consistent pronunciation models for phonemic variants
CSIR Research Space (South Africa)
Davel, M
2006-09-01
Full Text Available Pronunciation lexicons often contain pronunciation variants. This can create two problems: It can be difficult to define these variants in an internally consistent way and it can also be difficult to extract generalised grapheme-to-phoneme rule sets...
International Nuclear Information System (INIS)
Souza Pereira, Wagner de; Kelecom, Alphonse
2008-01-01
Attention has been paid only recently to the protection of biota against radiation effects. Protection is being considered through modeling of the calculation of absorbed dose rate. In these models, the inputs are the fluxes of radionuclides of environmental concern and their resulting distribution between environmental compartments. Such distribution is estimated for dispersion models. In freshwater systems and when fish is used as biomaker, relevant environmental transfer parameters are transfer between sediment and water (sediment distribution coefficients KD, in l kg -1 ), and between water and fish (concentration factor CF, in l kg -1 ). These coefficients are under the influence of a number o physical, chemical and biological factors, and display following the literature a great variability. The present work establishes the KD's and CF's for uranium, thorium, radium and lead for two ponds: one that receives treated effluents from an ore treatment unit (UTM) situated at Pocos de Caldas, Minas Gerais, Brazil and the other pond from the uranium concentration unit (URA) situated at Caetite, Bahia, Brazil, and for fish used as biomarker. It intends also to compare these parameters with the values recommended by IAEA. Depending on considered radionuclide and on the site, CF's (l kg -1 ) observed values were of the same magnitude as, or one order of magnitude lower than recommended by IAEA. KD's (l kg -1 ) observed values were found of the same magnitude as those recommended by IAEA, approximately 10 times lower or up to 100 times higher than recommended by IAEA, again depending on the radionuclides and on the site. It can be concluded that local parameters should be established in order to obtain a more accurate estimative of biota exposition from man activities. (author)
Fréour , Sylvain; Gloaguen , David; François , Marc; Guillén , Ronald
2006-01-01
International audience; The scope of this work is the determination of the coefficients of thermal expansion of the Ti-17 beta-phase. A rigorous inverse thermo-elastic self-consistent scale transition inicro-mechanical model extended to multi-phase materials was used. The experimental data required for the application of the inverse method were obtained from both the available literature and especially dedicated X-ray diffraction lattice strain measurements performed on the studied (alpha + b...
International Nuclear Information System (INIS)
Van den Bossche, P.; Schrijver, N.; Faber, G.
2007-01-01
Over the last two years, the debate in the Netherlands on trade measures addressing non-trade concerns has focused on two important and politically sensitive issues, namely: (1) the sustainability of the large-scale production of biomass as an alternative source of energy; and (2) the production of livestock products in a manner that is consistent with animal welfare requirements. In February 2007 a report was issued on the 'Toetsingskader voor Duurzame Biomassa', the so-called Cramer Report. This report discusses the risks associated with large-scale biomass production and establishes a list of criteria for the sustainable production of biomass. These criteria reflect a broad range of non-trade concerns, including environmental protection, global warming, food security, biodiversity, economic prosperity and social welfare. The report recognizes that the implementation of the criteria (including the establishment of a certification system) will require careful consideration of the obligations of the Netherlands under EU and WTO law. Governments called upon to address non-trade concerns may do so by using different types of measures. Prominent among these are measures concerning processes and production methods of products. In the present study, these issues are examined primarily with regard to existing, proposed or still purely hypothetical measures for implementing the Cramer criteria for the sustainable production of biomass. Several other, non-energy-related issues are discussed in this report
Sabine absorption coefficients to random incidence absorption coefficients
DEFF Research Database (Denmark)
Jeong, Cheol-Ho
2014-01-01
into random incidence absorption coefficients for porous absorbers are investigated. Two optimization-based conversion methods are suggested: the surface impedance estimation for locally reacting absorbers and the flow resistivity estimation for extendedly reacting absorbers. The suggested conversion methods...
Directory of Open Access Journals (Sweden)
Depetris Guiguet, Edith
2010-01-01
Full Text Available Este artículo tiene como objetivo evaluar, en términos de su consistencia cardinal, ordinal y dicotómica, cinco indicadores alternativos de especialización comercial. Tres están basados en el enfoque de las ventajas comparativas reveladas: una versión simétrica del índice de Balassa, el chi-cuadrado y el índice de Ventajas Relativas del Comercio. Los otros dos están basados en el enfoque de la balanza comercial: una variante del índice de Michaely y otra del índice de Iapadre. Se aplica al caso particular del comercio mundial de mantequilla de Argentina y Uruguay en el período 1995-2006. Los resultados varían entre los dos países, habiéndose encontrado que algunos indicadores podrían utilizarse de manera sustitutiva mientras que otros deberían utilizarse de manera complementaria. En términos económicos, se detecta una especialización fluctuante según los años en Argentina y mucha estabilidad en Uruguay. // This study aims to evaluate, in terms of their cardinal, ordinal, and dichotomy consistency, five alternative comercial specialization indicators: a Balassa symmetric index version; a Chi-Squared Index; and the Relative Trade Advantage Index, all these three based on revealed comparative advantage theory; and two additional: Michaely Index variation, and Iapadre Index variation, based on trade balance flows. It is applied to the particular case of Argentina and Uruguay butter world trade during 1995-2006. The results vary for both countries. Some indicators are found to be useful as substitutes while other in a complementary manner. Economically, the indicators show that the Argentine specialization fluctuates among years while the Uruguayan is very stable.
Probability based calibration of pressure coefficients
DEFF Research Database (Denmark)
Hansen, Svend Ole; Pedersen, Marie Louise; Sørensen, John Dalsgaard
2015-01-01
Normally, a consistent basis for calculating partial factors focuses on a homogeneous reliability index neither depending on which material the structure is constructed of nor the ratio between the permanent and variable actions acting on the structure. Furthermore, the reliability index should n...... the characteristic shape coefficients are based on mean values as specified in background documents to the Eurocodes. Importance of hidden safeties judging the reliability is discussed for wind actions on low-rise structures....... not depend on the type of variable action. A probability based calibration of pressure coefficients have been carried out using pressure measurements on the standard CAARC building modelled on scale of 1:383. The extreme pressures measured on the CAARC building model in the wind tunnel have been fitted.......3, the Eurocode partial factor of 1.5 for variable actions agrees well with the inherent uncertainties of wind actions when the pressure coefficients are determined using wind tunnel test results. The increased bias and uncertainty when pressure coefficients mainly are based on structural codes lead to a larger...
Measuring process and knowledge consistency
DEFF Research Database (Denmark)
Edwards, Kasper; Jensen, Klaes Ladeby; Haug, Anders
2007-01-01
When implementing configuration systems, knowledge about products and processes are documented and replicated in the configuration system. This practice assumes that products are specified consistently i.e. on the same rule base and likewise for processes. However, consistency cannot be taken...... for granted; rather the contrary, and attempting to implement a configuration system may easily ignite a political battle. This is because stakes are high in the sense that the rules and processes chosen may only reflect one part of the practice, ignoring a majority of the employees. To avoid this situation......, this paper presents a methodology for measuring product and process consistency prior to implementing a configuration system. The methodology consists of two parts: 1) measuring knowledge consistency and 2) measuring process consistency. Knowledge consistency is measured by developing a questionnaire...
Probabilistic optimization of safety coefficients
International Nuclear Information System (INIS)
Marques, M.; Devictor, N.; Magistris, F. de
1999-01-01
This article describes a reliability-based method for the optimization of safety coefficients defined and used in design codes. The purpose of the optimization is to determine the partial safety coefficients which minimize an objective function for sets of components and loading situations covered by a design rule. This objective function is a sum of distances between the reliability of the components designed using the safety coefficients and a target reliability. The advantage of this method is shown on the examples of the reactor vessel, a vapour pipe and the safety injection circuit. (authors)
Yasin, Muhammad; Park, Shinyoung; Jeong, Yeseul; Lee, Eun Yeol; Lee, Jinwon; Chang, In Seop
2014-10-01
This study proposed a submerged hollow fibre membrane bioreactor (HFMBR) system capable of achieving high carbon monoxide (CO) mass transfer for applications in microbial synthesis gas conversion systems. Hydrophobic polyvinylidene fluoride (PVDF) membrane fibres were used to fabricate a membrane module, which was used for pressurising CO in water phase. Pressure through the hollow fibre lumen (P) and membrane surface area per unit working volume of the liquid (A(S)/V(L)) were used as controllable parameters to determine gas-liquid volumetric mass transfer coefficient (k(L)a) values. We found a k(L)a of 135.72 h(-1) when P was 93.76 kPa and AS/VL was fixed at 27.5m(-1). A higher k(L)a of 155.16 h(-1) was achieved by increasing AS/VL to 62.5m(-1) at a lower P of 37.23 kPa. Practicality of HFMBR to support microbial growth and organic product formation was assessed by CO/CO2 fermentation using Eubacterium limosum KIST612. Copyright © 2014 Elsevier Ltd. All rights reserved.
Transport coefficients of a dissociating gas
International Nuclear Information System (INIS)
Lebed', I.V.
1987-01-01
The calculation of the transport coefficients of a dissociating gas involves fundamental difficulties which arise when the internal degrees of freedom of the molecules are taken strictly into account. In practical calculations extensive use is made of the approximation in the context of which the dependence of a diffusion velocity of the molecule on its internal state is totally neglected. In this case the expressions for the stress tensor and the diffusion velocities coincide with the corresponding expressions for a mixture of structureless particles; in the expression for the heat flux the diffusion transport of internal energy is taken only approximately into account. Here, analytic expressions for the diffusion velocities, heat flux and stress tensor are obtained without introducing simplifying assumptions. The calculation method is based on an approximate method of calculating the transport coefficients of a multicomponent mixture of structureless particles. The relations obtained are analyzed and compared with the existing results; their accuracy is estimated. A closed system of equations of gas dynamics is presented for a number of cases of practical importance
Quadrature formulas for Fourier coefficients
Bojanov, Borislav; Petrova, Guergana
2009-01-01
We consider quadrature formulas of high degree of precision for the computation of the Fourier coefficients in expansions of functions with respect to a system of orthogonal polynomials. In particular, we show the uniqueness of a multiple node
Diffusion coefficient for anomalous transport
International Nuclear Information System (INIS)
1986-01-01
A report on the progress towards the goal of estimating the diffusion coefficient for anomalous transport is given. The gyrokinetic theory is used to identify different time and length scale inherent to the characteristics of plasmas which exhibit anomalous transport
Fuel Temperature Coefficient of Reactivity
Energy Technology Data Exchange (ETDEWEB)
Loewe, W.E.
2001-07-31
A method for measuring the fuel temperature coefficient of reactivity in a heterogeneous nuclear reactor is presented. The method, which is used during normal operation, requires that calibrated control rods be oscillated in a special way at a high reactor power level. The value of the fuel temperature coefficient of reactivity is found from the measured flux responses to these oscillations. Application of the method in a Savannah River reactor charged with natural uranium is discussed.
Properties of Traffic Risk Coefficient
Tang, Tie-Qiao; Huang, Hai-Jun; Shang, Hua-Yan; Xue, Yu
2009-10-01
We use the model with the consideration of the traffic interruption probability (Physica A 387(2008)6845) to study the relationship between the traffic risk coefficient and the traffic interruption probability. The analytical and numerical results show that the traffic interruption probability will reduce the traffic risk coefficient and that the reduction is related to the density, which shows that this model can improve traffic security.
Heat transfer coefficients during quenching of steels
Energy Technology Data Exchange (ETDEWEB)
Hasan, H.S.; Jalil, J.M. [University of Technology, Department of Electromechanical Engineering, Baghdad (Iraq); Peet, M.J.; Bhadeshia, H.K.D.H. [University of Cambridge, Department of Materials Science and Metallurgy, Cambridge (United Kingdom)
2011-03-15
Heat transfer coefficients for quenching in water have been measured as a function of temperature using steel probes for a variety of iron alloys. The coefficients were derived from measured cooling curves combined with calculated heat-capacities. The resulting data were then used to calculate cooling curves using the finite volume method for a large steel sample and these curves have been demonstrated to be consistent with measured values for the large sample. Furthermore, by combining the estimated cooling curves with time-temperature-transformation (TTT) diagrams it has been possible to predict the variation of hardness as a function of distance via the quench factor analysis. The work should prove useful in the heat treatment of the steels studied, some of which are in the development stage. (orig.)
Clustering Coefficients for Correlation Networks.
Masuda, Naoki; Sakaki, Michiko; Ezaki, Takahiro; Watanabe, Takamitsu
2018-01-01
Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other) measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node) are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients were strongly
Clustering Coefficients for Correlation Networks
Directory of Open Access Journals (Sweden)
Naoki Masuda
2018-03-01
Full Text Available Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients
Clustering Coefficients for Correlation Networks
Masuda, Naoki; Sakaki, Michiko; Ezaki, Takahiro; Watanabe, Takamitsu
2018-01-01
Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other) measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node) are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients were strongly
Converting Sabine absorption coefficients to random incidence absorption coefficients
DEFF Research Database (Denmark)
Jeong, Cheol-Ho
2013-01-01
are suggested: An optimization method for the surface impedances for locally reacting absorbers, the flow resistivity for extendedly reacting absorbers, and the flow resistance for fabrics. With four porous type absorbers, the conversion methods are validated. For absorbers backed by a rigid wall, the surface...... coefficients to random incidence absorption coefficients are proposed. The overestimations of the Sabine absorption coefficient are investigated theoretically based on Miki's model for porous absorbers backed by a rigid wall or an air cavity, resulting in conversion factors. Additionally, three optimizations...... impedance optimization produces the best results, while the flow resistivity optimization also yields reasonable results. The flow resistivity and flow resistance optimization for extendedly reacting absorbers are also found to be successful. However, the theoretical conversion factors based on Miki's model...
Near-unity mass accommodation coefficient of organic molecules of varying structure.
Julin, Jan; Winkler, Paul M; Donahue, Neil M; Wagner, Paul E; Riipinen, Ilona
2014-10-21
Atmospheric aerosol particles have a significant effect on global climate, air quality, and consequently human health. Condensation of organic vapors is a key process in the growth of nanometer-sized particles to climate relevant sizes. This growth is very sensitive to the mass accommodation coefficient α, a quantity describing the vapor uptake ability of the particles, but knowledge on α of atmospheric organics is lacking. In this work, we have determined α for four organic molecules with diverse structural properties: adipic acid, succinic acid, naphthalene, and nonane. The coefficients are studied using molecular dynamics simulations, complemented with expansion chamber measurements. Our results are consistent with α = 1 (indicating nearly perfect accommodation), regardless of the molecular structural properties, the phase state of the bulk condensed phase, or surface curvature. The results highlight the need for experimental techniques capable of resolving the internal structure of nanoparticles to better constrain the accommodation of atmospheric organics.
Consistency argued students of fluid
Viyanti; Cari; Suparmi; Winarti; Slamet Budiarti, Indah; Handika, Jeffry; Widyastuti, Fatma
2017-01-01
Problem solving for physics concepts through consistency arguments can improve thinking skills of students and it is an important thing in science. The study aims to assess the consistency of the material Fluid student argmentation. The population of this study are College students PGRI Madiun, UIN Sunan Kalijaga Yogyakarta and Lampung University. Samples using cluster random sampling, 145 samples obtained by the number of students. The study used a descriptive survey method. Data obtained through multiple-choice test and interview reasoned. Problem fluid modified from [9] and [1]. The results of the study gained an average consistency argmentation for the right consistency, consistency is wrong, and inconsistent respectively 4.85%; 29.93%; and 65.23%. Data from the study have an impact on the lack of understanding of the fluid material which is ideally in full consistency argued affect the expansion of understanding of the concept. The results of the study as a reference in making improvements in future studies is to obtain a positive change in the consistency of argumentations.
26 CFR 301.6224(c)-3 - Consistent settlements.
2010-04-01
... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Consistent settlements. 301.6224(c)-3 Section... settlements. (a) In general. If the Internal Revenue Service enters into a settlement agreement with any..., settlement terms consistent with those contained in the settlement agreement entered into. (b) Requirements...
Power coefficient anomaly in JOYO
Energy Technology Data Exchange (ETDEWEB)
Yamamoto, H
1980-12-15
Operation of the JOYO experimental fast reactor with the MK-I core has been divided into two phases: (1) 50 MWt power ascension and operation; and (2) 75 MWt power ascension and operation. The 50 MWt power-up tests were conducted in August 1978. In these tests, the measured reactivity loss due to power increases from 15 MWt to 50 MWt was 0.28% ..delta.. K/K, and agreed well with the predicted value of 0.27% ..delta.. K/K. The 75 MWt power ascension tests were conducted in July-August 1979. In the process of the first power increase above 50 MWt to 65 MWt conducted on July 11, 1979, an anomalously large negative power coefficient was observed. The value was about twice the power coefficient values measured in the tests below 50 MW. In order to reproduce the anomaly, the reactor power was decreased and again increased up to the maximum power of 65 MWt. However, the large negative power coefficient was not observed at this time. In the succeeding power increase from 65 MWt to 75 MWt, a similar anomalous power coefficient was again observed. This anomaly disappeared in the subsequent power ascensions to 75 MWt, and the magnitude of the power coefficient gradually decreased with power cycles above the 50 MWt level.
Coordinating user interfaces for consistency
Nielsen, Jakob
2001-01-01
In the years since Jakob Nielsen's classic collection on interface consistency first appeared, much has changed, and much has stayed the same. On the one hand, there's been exponential growth in the opportunities for following or disregarding the principles of interface consistency-more computers, more applications, more users, and of course the vast expanse of the Web. On the other, there are the principles themselves, as persistent and as valuable as ever. In these contributed chapters, you'll find details on many methods for seeking and enforcing consistency, along with bottom-line analys
Relativistic phenomenological equations and transformation laws of relative coefficients
Directory of Open Access Journals (Sweden)
Patrizia Rogolino
2017-06-01
Full Text Available The aim of this paper is to derive the phenomenological equations in the context of special relativistic non-equilibrium thermodynamics with internal variables. In particular, after introducing some results developed in our previous paper, by means of classical non-equilibrium thermodynamic procedure and under suitable assumptions on the entropy density production, the phenomenological equations and transformation laws of phenomenological coefficients are derived. Finally, some symmetries of aforementioned coefficients are obtained.
On the internal consistency of holographic dark energy models
International Nuclear Information System (INIS)
Horvat, R
2008-01-01
Holographic dark energy (HDE) models, underpinned by an effective quantum field theory (QFT) with a manifest UV/IR connection, have become convincing candidates for providing an explanation of the dark energy in the universe. On the other hand, the maximum number of quantum states that a conventional QFT for a box of size L is capable of describing relates to those boxes which are on the brink of experiencing a sudden collapse to a black hole. Another restriction on the underlying QFT is that the UV cut-off, which cannot be chosen independently of the IR cut-off and therefore becomes a function of time in a cosmological setting, should stay the largest energy scale even in the standard cosmological epochs preceding a dark energy dominated one. We show that, irrespective of whether one deals with the saturated form of HDE or takes a certain degree of non-saturation in the past, the above restrictions cannot be met in a radiation dominated universe, an epoch in the history of the universe which is expected to be perfectly describable within conventional QFT
International Nuclear Information System (INIS)
Rafelski, J.
1979-01-01
After an introductory overview of the bag model the author uses the self-consistent solution of the coupled Dirac-meson fields to represent a bound state of strongly ineteracting fermions. In this framework he discusses the vivial approach to classical field equations. After a short description of the used numerical methods the properties of bound states of scalar self-consistent Fields and the solutions of a self-coupled Dirac field are considered. (HSI) [de
Conversion coefficients and yrast state spins in 180Os
International Nuclear Information System (INIS)
Dracoulis, G.D.; Kibedi, T.; Byrne, A.P.; Fabricius, B.; Stuchbery, A.E.
1989-11-01
Internal conversion coefficients of transitions in 180 Os have been measured using a superconducting, solenoidal electron spectrometer, operated in the lens mode. The high energy resolution and efficiency allow a precise measurement of the conversion coefficients of the 528 keV yrast transition. The values obtained, α K = 0.015 (2), α L = 0.004(1) define pure E2 multipolarity. Taken with the measured γ-ray angular distribution, the conversion coefficient leads to an unambiguous assignment of 16 + →14 + for the 528 keV transition. 14 refs., 5 figs., 1 tab
Algebraic polynomials with random coefficients
Directory of Open Access Journals (Sweden)
K. Farahmand
2002-01-01
Full Text Available This paper provides an asymptotic value for the mathematical expected number of points of inflections of a random polynomial of the form a0(ω+a1(ω(n11/2x+a2(ω(n21/2x2+…an(ω(nn1/2xn when n is large. The coefficients {aj(w}j=0n, w∈Ω are assumed to be a sequence of independent normally distributed random variables with means zero and variance one, each defined on a fixed probability space (A,Ω,Pr. A special case of dependent coefficients is also studied.
2012-05-01
Education: Physics Education Networks meeting has global scale Competition: Competition seeks the next Brian Cox Experiment: New measurement of neutrino time-of-flight consistent with the speed of light Event: A day for all those who teach physics Conference: Students attend first Anglo-Japanese international science conference Celebration: Will 2015 be the 'Year of Light'? Teachers: Challenging our intuition in spectacular fashion: the fascinating world of quantum physics awaits Research: Science sharpens up sport Learning: Kittinger and Baumgartner: on a mission to the edge of space International: London International Youth Science Forum calls for leading young scientists Competition: Physics paralympian challenge needs inquisitive, analytical, artistic and eloquent pupils Forthcoming events
Non linear self consistency of microtearing modes
International Nuclear Information System (INIS)
Garbet, X.; Mourgues, F.; Samain, A.
1987-01-01
The self consistency of a microtearing turbulence is studied in non linear regimes where the ergodicity of the flux lines determines the electron response. The current which sustains the magnetic perturbation via the Ampere law results from the combines action of the radial electric field in the frame where the island chains are static and of the thermal electron diamagnetism. Numerical calculations show that at usual values of β pol in Tokamaks the turbulence can create a diffusion coefficient of order ν th p 2 i where p i is the ion larmor radius and ν th the electron ion collision frequency. On the other hand, collisionless regimes involving special profiles of each mode near the resonant surface seem possible
Veliyath, Rajaram; Adams, Janet S.
2005-01-01
The course syllabus is a contract between instructor and students, a schedule of course assignments and activities, and a roadmap delineating objectives and checkpoints in the course. It is also a planning and reference tool for both students and instructor, and it models professors' expectations for their students. This study investigated whether…
Time-consistent and market-consistent evaluations
Pelsser, A.; Stadje, M.A.
2014-01-01
We consider evaluation methods for payoffs with an inherent financial risk as encountered for instance for portfolios held by pension funds and insurance companies. Pricing such payoffs in a way consistent to market prices typically involves combining actuarial techniques with methods from
Directory of Open Access Journals (Sweden)
José Gabriel Vieira Neto
2016-04-01
Full Text Available ABSTRACT Widely disseminated in both national and international scenarios, greenhouses are agribusiness solutions which are designed to allow for greater efficiency and control of the cultivation of plants. Bearing this in mind, the construction of greenhouses should take into consideration the incidence of wind, and other such aspects of comfort and safety, and ensure they are factored into the design of structural elements. In this study, we evaluated the effects of pressure coefficients established by the European standard EN 13031-1 (2001 and the Brazilian standard ABNT (1988, which are applicable to the structures of greenhouses with flat roofs, taking into account the following variables: roof slope, external and internal pressure coefficients and height-span ratio of the structure. Using the ANSYSTM computer program, zones of columns and roof were discretized by the Beam44 finite element to identify the maximum and minimum stress portions connected to the aerodynamic coefficients. With this analysis, we found that, in the smallest roof slope (a equal to 20°, the frame stress was quite similar for standards adopted. On the other hand, for the greatest inclination (a equal to 26°, the stress was consistently lower under the Brazilian standard. In view of this, we came to the conclusion that the differences between stresses when applying both standards were more significant at the higher degrees of height-span ratio and roof slope.
Recommended ALIs and DACs for 10 CFR part 220: A consistent numerical set
Energy Technology Data Exchange (ETDEWEB)
Eckerman, K.F.
1996-05-01
Appendix B to 10 CFR Part 20 contains numerical data for controlling the intake of radionuclides in the workplace or in the environment. These data, derived from the recommendations of the International Commission on Radiological Protection (ICRP), do not provide a numerically consistent basis for demonstrating compliance with the limitation on dose stated in the regulation. This situation is largely a consequence of the numerical procedures used by the ICRP which did not maintain, in a strict numerical sense, the hierarchial relationship among the radiation protection quantities. In this work recommended values of the quantities in Appendix B to CFR Part 20 are developed using the dose coefficients of the applicable ICRP publications and a numerical procedure which ensures that the tabulated quantities are numerically consistent.
Irrational "Coefficients" in Renaissance Algebra.
Oaks, Jeffrey A
2017-06-01
Argument From the time of al-Khwārizmī in the ninth century to the beginning of the sixteenth century algebraists did not allow irrational numbers to serve as coefficients. To multiply by x, for instance, the result was expressed as the rhetorical equivalent of . The reason for this practice has to do with the premodern concept of a monomial. The coefficient, or "number," of a term was thought of as how many of that term are present, and not as the scalar multiple that we work with today. Then, in sixteenth-century Europe, a few algebraists began to allow for irrational coefficients in their notation. Christoff Rudolff (1525) was the first to admit them in special cases, and subsequently they appear more liberally in Cardano (1539), Scheubel (1550), Bombelli (1572), and others, though most algebraists continued to ban them. We survey this development by examining the texts that show irrational coefficients and those that argue against them. We show that the debate took place entirely in the conceptual context of premodern, "cossic" algebra, and persisted in the sixteenth century independent of the development of the new algebra of Viète, Decartes, and Fermat. This was a formal innovation violating prevailing concepts that we propose could only be introduced because of the growing autonomy of notation from rhetorical text.
Integer Solutions of Binomial Coefficients
Gilbertson, Nicholas J.
2016-01-01
A good formula is like a good story, rich in description, powerful in communication, and eye-opening to readers. The formula presented in this article for determining the coefficients of the binomial expansion of (x + y)n is one such "good read." The beauty of this formula is in its simplicity--both describing a quantitative situation…
Verifying reciprocal relations for experimental diffusion coefficients in multicomponent mixtures
DEFF Research Database (Denmark)
Medvedev, Oleg; Shapiro, Alexander
2003-01-01
The goal of the present study is to verify the agreement of the available data on diffusion in ternary mixtures with the theoretical requirement of linear non-equilibrium thermodynamics consisting in symmetry of the matrix of the phenomenological coefficients. A common set of measured diffusion...... coefficients for a three-component mixture consists of four Fickian diffusion coefficients, each being reported separately. However, the Onsager theory predicts the existence of only three independent coefficients, as one of them disappears due to the symmetry requirement. Re-calculation of the Fickian...... extended sets of experimental data and reliable thermodynamic models were available. The sensitivity of the symmetry property to different thermodynamic parameters of the models was also checked. (C) 2003 Elsevier Science B.V. All rights reserved....
Market-consistent actuarial valuation
Wüthrich, Mario V
2016-01-01
This is the third edition of this well-received textbook, presenting powerful methods for measuring insurance liabilities and assets in a consistent way, with detailed mathematical frameworks that lead to market-consistent values for liabilities. Topics covered are stochastic discounting with deflators, valuation portfolio in life and non-life insurance, probability distortions, asset and liability management, financial risks, insurance technical risks, and solvency. Including updates on recent developments and regulatory changes under Solvency II, this new edition of Market-Consistent Actuarial Valuation also elaborates on different risk measures, providing a revised definition of solvency based on industry practice, and presents an adapted valuation framework which takes a dynamic view of non-life insurance reserving risk.
The Principle of Energetic Consistency
Cohn, Stephen E.
2009-01-01
A basic result in estimation theory is that the minimum variance estimate of the dynamical state, given the observations, is the conditional mean estimate. This result holds independently of the specifics of any dynamical or observation nonlinearity or stochasticity, requiring only that the probability density function of the state, conditioned on the observations, has two moments. For nonlinear dynamics that conserve a total energy, this general result implies the principle of energetic consistency: if the dynamical variables are taken to be the natural energy variables, then the sum of the total energy of the conditional mean and the trace of the conditional covariance matrix (the total variance) is constant between observations. Ensemble Kalman filtering methods are designed to approximate the evolution of the conditional mean and covariance matrix. For them the principle of energetic consistency holds independently of ensemble size, even with covariance localization. However, full Kalman filter experiments with advection dynamics have shown that a small amount of numerical dissipation can cause a large, state-dependent loss of total variance, to the detriment of filter performance. The principle of energetic consistency offers a simple way to test whether this spurious loss of variance limits ensemble filter performance in full-blown applications. The classical second-moment closure (third-moment discard) equations also satisfy the principle of energetic consistency, independently of the rank of the conditional covariance matrix. Low-rank approximation of these equations offers an energetically consistent, computationally viable alternative to ensemble filtering. Current formulations of long-window, weak-constraint, four-dimensional variational methods are designed to approximate the conditional mode rather than the conditional mean. Thus they neglect the nonlinear bias term in the second-moment closure equation for the conditional mean. The principle of
Weak consistency and strong paraconsistency
Directory of Open Access Journals (Sweden)
Gemma Robles
2009-11-01
Full Text Available In a standard sense, consistency and paraconsistency are understood as, respectively, the absence of any contradiction and as the absence of the ECQ (“E contradictione quodlibet” rule that allows us to conclude any well formed formula from any contradiction. The aim of this paper is to explain the concepts of weak consistency alternative to the standard one, the concepts of paraconsistency related to them and the concept of strong paraconsistency, all of which have been defined by the author together with José M. Méndez.
Glass consistency and glass performance
International Nuclear Information System (INIS)
Plodinec, M.J.; Ramsey, W.G.
1994-01-01
Glass produced by the Defense Waste Processing Facility (DWPF) will have to consistently be more durable than a benchmark glass (evaluated using a short-term leach test), with high confidence. The DWPF has developed a Glass Product Control Program to comply with this specification. However, it is not clear what relevance product consistency has on long-term glass performance. In this report, the authors show that DWPF glass, produced in compliance with this specification, can be expected to effectively limit the release of soluble radionuclides to natural environments. However, the release of insoluble radionuclides to the environment will be limited by their solubility, and not glass durability
Robust Stabilization of Nonlinear Systems with Uncertain Varying Control Coefficient
Directory of Open Access Journals (Sweden)
Zaiyue Yang
2014-01-01
Full Text Available This paper investigates the stabilization problem for a class of nonlinear systems, whose control coefficient is uncertain and varies continuously in value and sign. The study emphasizes the development of a robust control that consists of a modified Nussbaum function to tackle the uncertain varying control coefficient. By such a method, the finite-time escape phenomenon has been prevented when the control coefficient is crossing zero and varying its sign. The proposed control guarantees the asymptotic stabilization of the system and boundedness of all closed-loop signals. The control performance is illustrated by a numerical simulation.
Time-consistent actuarial valuations
Pelsser, A.A.J.; Salahnejhad Ghalehjooghi, A.
2016-01-01
Time-consistent valuations (i.e. pricing operators) can be created by backward iteration of one-period valuations. In this paper we investigate the continuous-time limits of well-known actuarial premium principles when such backward iteration procedures are applied. This method is applied to an
Dynamically consistent oil import tariffs
International Nuclear Information System (INIS)
Karp, L.; Newbery, D.M.
1992-01-01
The standard theory of optimal tariffs considers tariffs on perishable goods produced abroad under static conditions, in which tariffs affect prices only in that period. Oil and other exhaustable resources do not fit this model, for current tariffs affect the amount of oil imported, which will affect the remaining stock and hence its future price. The problem of choosing a dynamically consistent oil import tariff when suppliers are competitive but importers have market power is considered. The open-loop Nash tariff is solved for the standard competitive case in which the oil price is arbitraged, and it was found that the resulting tariff rises at the rate of interest. This tariff was found to have an equilibrium that in general is dynamically inconsistent. Nevertheless, it is shown that necessary and sufficient conditions exist under which the tariff satisfies the weaker condition of time consistency. A dynamically consistent tariff is obtained by assuming that all agents condition their current decisions on the remaining stock of the resource, in contrast to open-loop strategies. For the natural case in which all agents choose their actions simultaneously in each period, the dynamically consistent tariff was characterized, and found to differ markedly from the time-inconsistent open-loop tariff. It was shown that if importers do not have overwhelming market power, then the time path of the world price is insensitive to the ability to commit, as is the level of wealth achieved by the importer. 26 refs., 4 figs
26 CFR 1.338-8 - Asset and stock consistency.
2010-04-01
... that are controlled foreign corporations. (6) Stock consistency. This section limits the application of... 26 Internal Revenue 4 2010-04-01 2010-04-01 false Asset and stock consistency. 1.338-8 Section 1... (CONTINUED) INCOME TAXES Effects on Corporation § 1.338-8 Asset and stock consistency. (a) Introduction—(1...
Short-Cut Estimators of Criterion-Referenced Test Consistency.
Brown, James Dean
1990-01-01
Presents simplified methods for deriving estimates of the consistency of criterion-referenced, English-as-a-Second-Language tests, including (1) the threshold loss agreement approach using agreement or kappa coefficients, (2) the squared-error loss agreement approach using the phi(lambda) dependability approach, and (3) the domain score…
Consistently violating the non-Gaussian consistency relation
International Nuclear Information System (INIS)
Mooij, Sander; Palma, Gonzalo A.
2015-01-01
Non-attractor models of inflation are characterized by the super-horizon evolution of curvature perturbations, introducing a violation of the non-Gaussian consistency relation between the bispectrum's squeezed limit and the power spectrum's spectral index. In this work we show that the bispectrum's squeezed limit of non-attractor models continues to respect a relation dictated by the evolution of the background. We show how to derive this relation using only symmetry arguments, without ever needing to solve the equations of motion for the perturbations
Scheibler, Robin; Hurley, Paul
2012-03-01
We present a novel, accurate and fast algorithm to obtain Fourier series coefficients from an IC layer whose description consists of rectilinear polygons on a plane, and how to implement it using off-the-shelf hardware components. Based on properties of Fourier calculus, we derive a relationship between the Discrete Fourier Transforms of the sampled mask transmission function and its continuous Fourier series coefficients. The relationship leads to a straightforward algorithm for computing the continuous Fourier series coefficients where one samples the mask transmission function, compute its discrete Fourier transform and applies a frequency-dependent multiplicative factor. The algorithm is guaranteed to yield the exact continuous Fourier series coefficients for any sampling representing the mask function exactly. Computationally, this leads to significant saving by allowing to choose the maximal such pixel size and reducing the fast Fourier transform size by as much, without compromising accuracy. In addition, the continuous Fourier series is free from aliasing and follows closely the physical model of Fourier optics. We show that in some cases this can make a significant difference, especially in modern very low pitch technology nodes.
Consistence of Network Filtering Rules
Institute of Scientific and Technical Information of China (English)
SHE Kun; WU Yuancheng; HUANG Juncai; ZHOU Mingtian
2004-01-01
The inconsistence of firewall/VPN(Virtual Private Network) rule makes a huge maintainable cost.With development of Multinational Company,SOHO office,E-government the number of firewalls/VPN will increase rapidly.Rule table in stand-alone or network will be increased in geometric series accordingly.Checking the consistence of rule table manually is inadequate.A formal approach can define semantic consistence,make a theoretic foundation of intelligent management about rule tables.In this paper,a kind of formalization of host rules and network ones for auto rule-validation based on SET theory were proporsed and a rule validation scheme was defined.The analysis results show the superior performance of the methods and demonstrate its potential for the intelligent management based on rule tables.
International Nuclear Information System (INIS)
Hazeltine, R.D.
1988-12-01
The boundary layer arising in the radial vicinity of a tokamak limiter is examined, with special reference to the TEXT tokamak. It is shown that sheath structure depends upon the self-consistent effects of ion guiding-center orbit modification, as well as the radial variation of E /times/ B-induced toroidal rotation. Reasonable agreement with experiment is obtained from an idealized model which, however simplified, preserves such self-consistent effects. It is argued that the radial sheath, which occurs whenever confining magnetic field-lines lie in the plasma boundary surface, is an object of some intrinsic interest. It differs from the more familiar axial sheath because magnetized charges respond very differently to parallel and perpendicular electric fields. 11 refs., 1 fig
Lagrangian multiforms and multidimensional consistency
Energy Technology Data Exchange (ETDEWEB)
Lobb, Sarah; Nijhoff, Frank [Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT (United Kingdom)
2009-10-30
We show that well-chosen Lagrangians for a class of two-dimensional integrable lattice equations obey a closure relation when embedded in a higher dimensional lattice. On the basis of this property we formulate a Lagrangian description for such systems in terms of Lagrangian multiforms. We discuss the connection of this formalism with the notion of multidimensional consistency, and the role of the lattice from the point of view of the relevant variational principle.
Consistency and Communication in Committees
Inga Deimen; Felix Ketelaar; Mark T. Le Quement
2013-01-01
This paper analyzes truthtelling incentives in pre-vote communication in heterogeneous committees. We generalize the classical Condorcet jury model by introducing a new informational structure that captures consistency of information. In contrast to the impossibility result shown by Coughlan (2000) for the classical model, full pooling of information followed by sincere voting is an equilibrium outcome of our model for a large set of parameter values implying the possibility of ex post confli...
Deep Feature Consistent Variational Autoencoder
Hou, Xianxu; Shen, Linlin; Sun, Ke; Qiu, Guoping
2016-01-01
We present a novel method for constructing Variational Autoencoder (VAE). Instead of using pixel-by-pixel loss, we enforce deep feature consistency between the input and the output of a VAE, which ensures the VAE's output to preserve the spatial correlation characteristics of the input, thus leading the output to have a more natural visual appearance and better perceptual quality. Based on recent deep learning works such as style transfer, we employ a pre-trained deep convolutional neural net...
Extinction Coefficient of Gold Nanostars
de Puig, Helena; Tam, Justina O.; Yen, Chun-Wan; Gehrke, Lee; Hamad-Schifferli, Kimberly
2015-01-01
Gold nanostars (NStars) are highly attractive for biological applications due to their surface chemistry, facile synthesis and optical properties. Here, we synthesize NStars in HEPES buffer at different HEPES/Au ratios, producing NStars of different sizes and shapes, and therefore varying optical properties. We measure the extinction coefficient of the synthesized NStars at their maximum surface plasmon resonances (SPR), which range from 5.7 × 108 to 26.8 × 108 M−1cm−1. Measured values correl...
Self-consistent asset pricing models
Malevergne, Y.; Sornette, D.
2007-08-01
We discuss the foundations of factor or regression models in the light of the self-consistency condition that the market portfolio (and more generally the risk factors) is (are) constituted of the assets whose returns it is (they are) supposed to explain. As already reported in several articles, self-consistency implies correlations between the return disturbances. As a consequence, the alphas and betas of the factor model are unobservable. Self-consistency leads to renormalized betas with zero effective alphas, which are observable with standard OLS regressions. When the conditions derived from internal consistency are not met, the model is necessarily incomplete, which means that some sources of risk cannot be replicated (or hedged) by a portfolio of stocks traded on the market, even for infinite economies. Analytical derivations and numerical simulations show that, for arbitrary choices of the proxy which are different from the true market portfolio, a modified linear regression holds with a non-zero value αi at the origin between an asset i's return and the proxy's return. Self-consistency also introduces “orthogonality” and “normality” conditions linking the betas, alphas (as well as the residuals) and the weights of the proxy portfolio. Two diagnostics based on these orthogonality and normality conditions are implemented on a basket of 323 assets which have been components of the S&P500 in the period from January 1990 to February 2005. These two diagnostics show interesting departures from dynamical self-consistency starting about 2 years before the end of the Internet bubble. Assuming that the CAPM holds with the self-consistency condition, the OLS method automatically obeys the resulting orthogonality and normality conditions and therefore provides a simple way to self-consistently assess the parameters of the model by using proxy portfolios made only of the assets which are used in the CAPM regressions. Finally, the factor decomposition with the
Peltier Coefficient and Photon-Assisted Tunnelling in Quantum Point Contact
International Nuclear Information System (INIS)
Arafa, H. Aly
2008-01-01
We present the Peltier coefficient and thermal transport in quantum point contact (QPC), under the influence of external fields and different temperatures. Also we obtain the oscillations of the Peltier coefficient in external fields. Numerical calculations of the Peltier coefficient are performed at different applied voltages, amplitudes and temperatures. The obtained results are consistent with the experimental data in the literature
Form of multicomponent Fickian diffusion coefficients matrix
International Nuclear Information System (INIS)
Wambui Mutoru, J.; Firoozabadi, Abbas
2011-01-01
Highlights: → Irreversible thermodynamics establishes form of multicomponent diffusion coefficients. → Phenomenological coefficients and thermodynamic factors affect sign of diffusion coefficients. → Negative diagonal elements of diffusion coefficients matrix can occur in non-ideal mixtures. → Eigenvalues of the matrix of Fickian diffusion coefficients may not be all real. - Abstract: The form of multicomponent Fickian diffusion coefficients matrix in thermodynamically stable mixtures is established based on the form of phenomenological coefficients and thermodynamic factors. While phenomenological coefficients form a symmetric positive definite matrix, the determinant of thermodynamic factors matrix is positive. As a result, the Fickian diffusion coefficients matrix has a positive determinant, but its elements - including diagonal elements - can be negative. Comprehensive survey of reported diffusion coefficients data for ternary and quaternary mixtures, confirms that invariably the determinant of the Fickian diffusion coefficients matrix is positive.
On the reliability of the theoretical internal conversion coefficients
Czech Academy of Sciences Publication Activity Database
Ryšavý, Miloš; Dragoun, Otokar
2000-01-01
Roč. 26, - (2000), s. 1859-1872 ISSN 0954-3899 R&D Projects: GA ČR GA202/00/1625; GA AV ČR KSK1048601 Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.284, year: 2000
Age-dependent dose coefficients for tritium in Asian populations
International Nuclear Information System (INIS)
Trivedi, A.
1999-10-01
The International Commission on Radiological Protection (ICRP) Publications 56 (1989) and 67 (1993) have prescribed the biokinetic models and age-dependent dose coefficients for tritiated water and organically bound tritium. The dose coefficients are computed from values selected to specify the anatomical, morphological and physiological characteristics of a three-month-old, one-year-old, five-year-old, 10-year-old, 15-year-old and adult (Reference Man) Caucasian living in North America and Western Europe. However, values for Reference Man and other age groups are not directly applicable to Asians, because of differences in race, custom, dietary habits and climatic conditions. An Asian Man model, including five age groups, has been proposed by Tanaka and Kawamura (1996, 1998) for use in internal dosimetry. The basic concept of the ICRP Reference Man and the system describing body composition in ICRP Publication 23 (1975) were used. Reference values for Asians were given for the body weight and height, the mass of soft tissue, the mass of body water and the daily fluid balance, and are used to compute the dose coefficients for tritium. The age-dependent dose coefficients for Asians for tritiated water intakes are smaller by 20 to 30% of the currently prescribed values (Trivedi, 1998). The reduction in the dose coefficient values is caused by the increased daily fluid balance among Asians. The dose coefficient for tritiated water is 1.4 x 10 -11 Sv Bq -1 for Asian Man compared to 2.0 x 10 -11 Sv Bq -1 for Reference Man. The dose coefficients for organically bound tritium are only marginally different from those of the ICRP values. The dose coefficient for organically bound tritium for Asian Man is 4.0 x 10 -11 Sv Bq -11 compared to 4.6 x 10 -11 Sv Bq -1 for Reference Man. (author)
Age-dependent dose coefficients for tritium in Asian populations
Energy Technology Data Exchange (ETDEWEB)
Trivedi, A
1999-10-01
The International Commission on Radiological Protection (ICRP) Publications 56 (1989) and 67 (1993) have prescribed the biokinetic models and age-dependent dose coefficients for tritiated water and organically bound tritium. The dose coefficients are computed from values selected to specify the anatomical, morphological and physiological characteristics of a three-month-old, one-year-old, five-year-old, 10-year-old, 15-year-old and adult (Reference Man) Caucasian living in North America and Western Europe. However, values for Reference Man and other age groups are not directly applicable to Asians, because of differences in race, custom, dietary habits and climatic conditions. An Asian Man model, including five age groups, has been proposed by Tanaka and Kawamura (1996, 1998) for use in internal dosimetry. The basic concept of the ICRP Reference Man and the system describing body composition in ICRP Publication 23 (1975) were used. Reference values for Asians were given for the body weight and height, the mass of soft tissue, the mass of body water and the daily fluid balance, and are used to compute the dose coefficients for tritium. The age-dependent dose coefficients for Asians for tritiated water intakes are smaller by 20 to 30% of the currently prescribed values (Trivedi, 1998). The reduction in the dose coefficient values is caused by the increased daily fluid balance among Asians. The dose coefficient for tritiated water is 1.4 x 10{sup -11} Sv Bq{sup -1} for Asian Man compared to 2.0 x 10{sup -11} Sv Bq{sup -1} for Reference Man. The dose coefficients for organically bound tritium are only marginally different from those of the ICRP values. The dose coefficient for organically bound tritium for Asian Man is 4.0 x 10{sup -11} Sv Bq{sup -11} compared to 4.6 x 10{sup -11} Sv Bq{sup -1} for Reference Man. (author)
International Nuclear Information System (INIS)
Qiu, R.; Li, J.; Zhang, Z.; Liu, L.; Bi, L.; Ren, L.
2009-01-01
A set of conversion coefficients from kerma free-in-air to the organ-absorbed dose are presented for external monoenergetic photon beams from 10 keV to 10 MeV based on the Chinese mathematical phantom, a whole-body mathematical phantom model. The model was developed based on the methods of the Oak Ridge National Laboratory mathematical phantom series and data from the Chinese Reference Man and the Reference Asian Man. This work is carried out to obtain the conversion coefficients based on this model, which represents the characteristics of the Chinese population, as the anatomical parameters of the Chinese are different from those of Caucasians. Monte Carlo simulation with MCNP code is carried out to calculate the organ dose conversion coefficients. Before the calculation, the effects from the physics model and tally type are investigated, considering both the calculation efficiency and precision. In the calculation irradiation conditions include anterior-posterior, posterior-anterior, right lateral, left lateral, rotational and isotropic geometries. Conversion coefficients from this study are compared with those recommended in the Publication 74 of International Commission on Radiological Protection (ICRP74) since both the sets of data are calculated with mathematical phantoms. Overall, consistency between the two sets of data is observed and the difference for more than 60% of the data is below 10%. However, significant deviations are also found, mainly for the superficial organs (up to 65.9%) and bone surface (up to 66%). The big difference of the dose conversion coefficients for the superficial organs at high photon energy could be ascribed to kerma approximation for the data in ICRP74. Both anatomical variations between races and the calculation method contribute to the difference of the data for bone surface. (authors)
The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR
Energy Technology Data Exchange (ETDEWEB)
Kim, So Ra; Min, Byung Il; Park, Kihyun; Yang, Byung Mo; Suh, Kyung Suk [Nuclear Environmental Safety Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2016-12-15
The International Commission on Radiological Protection (ICRP) recommendations and the Federal Guidance Report (FGR) published by the U.S. Environmental Protection Agency (EPA) have been widely applied worldwide in the fields of radiation protection and dose assessment. The dose conversion coefficients of the ICRP and FGR are widely used for assessing exposure doses. However, before the coefficients are used, the user must thoroughly understand the derivation process of the coefficients to ensure that they are used appropriately in the evaluation. The ICRP provides recommendations to regulatory and advisory agencies, mainly in the form of guidance on the fundamental principles on which appropriate radiological protection can be based. The FGR provides federal and state agencies with technical information to assist their implementation of radiation protection programs for the U.S. population. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR is reviewed in this study. A thorough understanding of their background is essential for the proper use of dose conversion coefficients. The FGR dose assessment system was strongly influenced by the ICRP and the U.S. National Council on Radiation Protection and Measurements (NCRP), and is hence consistent with those recommendations. Moreover, the ICRP and FGR both used the scientific data reported by Biological Effects of Ionizing Radiation (BEIR) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as their primary source of information. The difference between the ICRP and FGR lies in the fact that the ICRP utilized information regarding a population of diverse races, whereas the FGR utilized data on the American population, as its goal was to provide guidelines for radiological protection in the US. The contents of this study are expected to be utilized as basic research material in the areas of radiation protection and dose assessment.
Qiu, Rui; Li, Junli; Zhang, Zhan; Liu, Liye; Bi, Lei; Ren, Li
2009-02-01
A set of conversion coefficients from kerma free-in-air to the organ-absorbed dose are presented for external monoenergetic photon beams from 10 keV to 10 MeV based on the Chinese mathematical phantom, a whole-body mathematical phantom model. The model was developed based on the methods of the Oak Ridge National Laboratory mathematical phantom series and data from the Chinese Reference Man and the Reference Asian Man. This work is carried out to obtain the conversion coefficients based on this model, which represents the characteristics of the Chinese population, as the anatomical parameters of the Chinese are different from those of Caucasians. Monte Carlo simulation with MCNP code is carried out to calculate the organ dose conversion coefficients. Before the calculation, the effects from the physics model and tally type are investigated, considering both the calculation efficiency and precision. In the calculation irradiation conditions include anterior-posterior, posterior-anterior, right lateral, left lateral, rotational and isotropic geometries. Conversion coefficients from this study are compared with those recommended in the Publication 74 of International Commission on Radiological Protection (ICRP74) since both the sets of data are calculated with mathematical phantoms. Overall, consistency between the two sets of data is observed and the difference for more than 60% of the data is below 10%. However, significant deviations are also found, mainly for the superficial organs (up to 65.9%) and bone surface (up to 66%). The big difference of the dose conversion coefficients for the superficial organs at high photon energy could be ascribed to kerma approximation for the data in ICRP74. Both anatomical variations between races and the calculation method contribute to the difference of the data for bone surface.
The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR
International Nuclear Information System (INIS)
Kim, So Ra; Min, Byung Il; Park, Kihyun; Yang, Byung Mo; Suh, Kyung Suk
2016-01-01
The International Commission on Radiological Protection (ICRP) recommendations and the Federal Guidance Report (FGR) published by the U.S. Environmental Protection Agency (EPA) have been widely applied worldwide in the fields of radiation protection and dose assessment. The dose conversion coefficients of the ICRP and FGR are widely used for assessing exposure doses. However, before the coefficients are used, the user must thoroughly understand the derivation process of the coefficients to ensure that they are used appropriately in the evaluation. The ICRP provides recommendations to regulatory and advisory agencies, mainly in the form of guidance on the fundamental principles on which appropriate radiological protection can be based. The FGR provides federal and state agencies with technical information to assist their implementation of radiation protection programs for the U.S. population. The system of radiation dose assessment and dose conversion coefficients in the ICRP and FGR is reviewed in this study. A thorough understanding of their background is essential for the proper use of dose conversion coefficients. The FGR dose assessment system was strongly influenced by the ICRP and the U.S. National Council on Radiation Protection and Measurements (NCRP), and is hence consistent with those recommendations. Moreover, the ICRP and FGR both used the scientific data reported by Biological Effects of Ionizing Radiation (BEIR) and United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) as their primary source of information. The difference between the ICRP and FGR lies in the fact that the ICRP utilized information regarding a population of diverse races, whereas the FGR utilized data on the American population, as its goal was to provide guidelines for radiological protection in the US. The contents of this study are expected to be utilized as basic research material in the areas of radiation protection and dose assessment
Consistent Partial Least Squares Path Modeling via Regularization.
Jung, Sunho; Park, JaeHong
2018-01-01
Partial least squares (PLS) path modeling is a component-based structural equation modeling that has been adopted in social and psychological research due to its data-analytic capability and flexibility. A recent methodological advance is consistent PLS (PLSc), designed to produce consistent estimates of path coefficients in structural models involving common factors. In practice, however, PLSc may frequently encounter multicollinearity in part because it takes a strategy of estimating path coefficients based on consistent correlations among independent latent variables. PLSc has yet no remedy for this multicollinearity problem, which can cause loss of statistical power and accuracy in parameter estimation. Thus, a ridge type of regularization is incorporated into PLSc, creating a new technique called regularized PLSc. A comprehensive simulation study is conducted to evaluate the performance of regularized PLSc as compared to its non-regularized counterpart in terms of power and accuracy. The results show that our regularized PLSc is recommended for use when serious multicollinearity is present.
Study of transport coefficients of nanodiamond nanofluids
Pryazhnikov, M. I.; Minakov, A. V.; Guzei, D. V.
2017-09-01
Experimental data on the thermal conductivity coefficient and viscosity coefficient of nanodiamond nanofluids are presented. Distilled water and ethylene glycol were used as the base fluid. Dependences of transport coefficients on concentration are obtained. It was shown that the thermal conductivity coefficient increases with increasing nanodiamonds concentration. It was shown that base fluids properties and nanodiamonds concentration affect on the rheology of nanofluids.
Directory of Open Access Journals (Sweden)
Qieni Lu
2015-08-01
Full Text Available We measure temperature dependence on Kerr coefficient and quadratic polarized optical coefficient of a paraelectric Mn:Fe:KTN crystal simultaneously in this work, based on digital holographic interferometry (DHI. And the spatial distribution of the field-induced refractive index change can also be visualized and estimated by numerically retrieving sequential phase maps of Mn:Fe:KTN crystal from recording digital holograms in different states. The refractive indices decrease with increasing temperature and quadratic polarized optical coefficient is insensitive to temperature. The experimental results suggest that the DHI method presented here is highly applicable in both visualizing the temporal and spatial behavior of the internal electric field and accurately measuring electro-optic coefficient for electrooptical media.
Breakdown coefficients and scaling properties of rain fields
Directory of Open Access Journals (Sweden)
D. Harris
1998-01-01
Full Text Available The theory of scale similarity and breakdown coefficients is applied here to intermittent rainfall data consisting of time series and spatial rain fields. The probability distributions (pdf of the logarithm of the breakdown coefficients are the principal descriptor used. Rain fields are distinguished as being either multiscaling or multiaffine depending on whether the pdfs of breakdown coefficients are scale similar or scale dependent, respectively. Parameter estimation techniques are developed which are applicable to both multiscaling and multiaffine fields. The scale parameter (width, σ, of the pdfs of the log-breakdown coefficients is a measure of the intermittency of a field. For multiaffine fields, this scale parameter is found to increase with scale in a power-law fashion consistent with a bounded-cascade picture of rainfall modelling. The resulting power-law exponent, H, is indicative of the smoothness of the field. Some details of breakdown coefficient analysis are addressed and a theoretical link between this analysis and moment scaling analysis is also presented. Breakdown coefficient properties of cascades are also investigated in the context of parameter estimation for modelling purposes.
Evaluation of Rock Joint Coefficients
Audy, Ondřej; Ficker, Tomáš
2017-10-01
A computer method for evaluation of rock joint coefficients is described and several applications are presented. The method is based on two absolute numerical indicators that are formed by means of the Fourier replicas of rock joint profiles. The first indicator quantifies the vertical depth of profiles and the second indicator classifies wavy character of profiles. The absolute indicators have replaced the formerly used relative indicators that showed some artificial behavior in some cases. This contribution is focused on practical computations testing the functionality of the newly introduced indicators.
Maintaining consistency in distributed systems
Birman, Kenneth P.
1991-01-01
In systems designed as assemblies of independently developed components, concurrent access to data or data structures normally arises within individual programs, and is controlled using mutual exclusion constructs, such as semaphores and monitors. Where data is persistent and/or sets of operation are related to one another, transactions or linearizability may be more appropriate. Systems that incorporate cooperative styles of distributed execution often replicate or distribute data within groups of components. In these cases, group oriented consistency properties must be maintained, and tools based on the virtual synchrony execution model greatly simplify the task confronting an application developer. All three styles of distributed computing are likely to be seen in future systems - often, within the same application. This leads us to propose an integrated approach that permits applications that use virtual synchrony with concurrent objects that respect a linearizability constraint, and vice versa. Transactional subsystems are treated as a special case of linearizability.
Correlation coefficients in neutron β-decay
International Nuclear Information System (INIS)
Byrne, J.
1978-01-01
The various angular and polarisation coefficients in neutron decay are the principal sources of information on the β-interaction. Measurements of the electron-neutrino angular correlation coefficient (a), the neutron-spin-electron-momentum correlation coefficient (A), the neutron-spin-neutrino-momentum correlation coefficient (B), and the triple correlation coefficient D and time-reversal invariance are reviewed and the results discussed. (U.K.)
Accounting for Missing Correlation Coefficients in Fixed-Effects MASEM.
Jak, Suzanne; Cheung, Mike W-L
2018-01-01
Meta-analytic structural equation modeling (MASEM) is increasingly applied to advance theories by synthesizing existing findings. MASEM essentially consists of two stages. In Stage 1, a pooled correlation matrix is estimated based on the reported correlation coefficients in the individual studies. In Stage 2, a structural model (such as a path model) is fitted to explain the pooled correlations. Frequently, the individual studies do not provide all the correlation coefficients between the research variables. In this study, we modify the currently optimal MASEM-method to deal with missing correlation coefficients, and compare its performance with existing methods. This study is the first to evaluate the performance of fixed-effects MASEM methods under different levels of missing correlation coefficients. We found that the often used univariate methods performed very poorly, while the multivariate methods performed well overall.
Transport Coefficients for Holographic Hydrodynamics at Finite Energy Scale
International Nuclear Information System (INIS)
Ge, Xian-Hui; Fang, Li Qing; Yang, Guo-Hong; Leng, Hong-Qiang
2014-01-01
We investigate the relations between black hole thermodynamics and holographic transport coefficients in this paper. The formulae for DC conductivity and diffusion coefficient are verified for electrically single-charged black holes. We examine the correctness of the proposed expressions by taking charged dilatonic and single-charged STU black holes as two concrete examples, and compute the flows of conductivity and diffusion coefficient by solving the linear order perturbation equations. We then check the consistence by evaluating the Brown-York tensor at a finite radial position. Finally, we find that the retarded Green functions for the shear modes can be expressed easily in terms of black hole thermodynamic quantities and transport coefficients
Use of appropriate absorption coefficients in gamma-ray dosimetry
International Nuclear Information System (INIS)
Gopinath, D.V.; Natarajan, A.; Subbaiah, K.V.
1985-01-01
The current use of the different types of absorption coefficients in the computation of γ-ray energy deposition rates and air dose is critically analyzed. Transport calculations are presented to bring out the errors associated with the use of different absorption coefficients. It is observed that except for source energies in the range of 0.3 to 3.0 MeV the consistent use of the absorption coefficient, μ/sub a/ results in an underestimate of the air dose everywhere and of energy deposition at regions away from source. The underestimate becomes more significant with increased atomic number (Z) of the medium. Based on the computations and analysis it is concluded that the absorption coefficients μ/sub a/ and μ/sub k/ are of very limited use in practical γ-ray dosimetry
Empirical evidence for site coefficients in building code provisions
Borcherdt, R.D.
2002-01-01
Site-response coefficients, Fa and Fv, used in U.S. building code provisions are based on empirical data for motions up to 0.1 g. For larger motions they are based on theoretical and laboratory results. The Northridge earthquake of 17 January 1994 provided a significant new set of empirical data up to 0.5 g. These data together with recent site characterizations based on shear-wave velocity measurements provide empirical estimates of the site coefficients at base accelerations up to 0.5 g for Site Classes C and D. These empirical estimates of Fa and Fnu; as well as their decrease with increasing base acceleration level are consistent at the 95 percent confidence level with those in present building code provisions, with the exception of estimates for Fa at levels of 0.1 and 0.2 g, which are less than the lower confidence bound by amounts up to 13 percent. The site-coefficient estimates are consistent at the 95 percent confidence level with those of several other investigators for base accelerations greater than 0.3 g. These consistencies and present code procedures indicate that changes in the site coefficients are not warranted. Empirical results for base accelerations greater than 0.2 g confirm the need for both a short- and a mid- or long-period site coefficient to characterize site response for purposes of estimating site-specific design spectra.
Decentralized Consistent Updates in SDN
Nguyen, Thanh Dang
2017-04-10
We present ez-Segway, a decentralized mechanism to consistently and quickly update the network state while preventing forwarding anomalies (loops and blackholes) and avoiding link congestion. In our design, the centralized SDN controller only pre-computes information needed by the switches during the update execution. This information is distributed to the switches, which use partial knowledge and direct message passing to efficiently realize the update. This separation of concerns has the key benefit of improving update performance as the communication and computation bottlenecks at the controller are removed. Our evaluations via network emulations and large-scale simulations demonstrate the efficiency of ez-Segway, which compared to a centralized approach, improves network update times by up to 45% and 57% at the median and the 99th percentile, respectively. A deployment of a system prototype in a real OpenFlow switch and an implementation in P4 demonstrate the feasibility and low overhead of implementing simple network update functionality within switches.
Consistent probabilities in loop quantum cosmology
International Nuclear Information System (INIS)
Craig, David A; Singh, Parampreet
2013-01-01
A fundamental issue for any quantum cosmological theory is to specify how probabilities can be assigned to various quantum events or sequences of events such as the occurrence of singularities or bounces. In previous work, we have demonstrated how this issue can be successfully addressed within the consistent histories approach to quantum theory for Wheeler–DeWitt-quantized cosmological models. In this work, we generalize that analysis to the exactly solvable loop quantization of a spatially flat, homogeneous and isotropic cosmology sourced with a massless, minimally coupled scalar field known as sLQC. We provide an explicit, rigorous and complete decoherent-histories formulation for this model and compute the probabilities for the occurrence of a quantum bounce versus a singularity. Using the scalar field as an emergent internal time, we show for generic states that the probability for a singularity to occur in this model is zero, and that of a bounce is unity, complementing earlier studies of the expectation values of the volume and matter density in this theory. We also show from the consistent histories point of view that all states in this model, whether quantum or classical, achieve arbitrarily large volume in the limit of infinite ‘past’ or ‘future’ scalar ‘time’, in the sense that the wave function evaluated at any arbitrary fixed value of the volume vanishes in that limit. Finally, we briefly discuss certain misconceptions concerning the utility of the consistent histories approach in these models. (paper)
International Nuclear Information System (INIS)
Endo, Akira; Petoussi-Henss, Nina; Zankl, Maria; Schlattl, Helmut; Bolch, Wesley E.; Eckerman, Keith F.; Hertel, Nolan E.; Hunt, John G.; Pelliccioni, Maurizio; Menzel, Hans-Georg
2014-01-01
This paper reviews the ICRP Publications 110 and 116 describing the reference computational phantoms and dose conversion coefficients for external exposures. The International Commission on Radiological Protection (ICRP) in its 2007 Recommendations made several revisions to the methods of calculation of the protection quantities. In order to implement these recommendations, the DOCAL task group of the ICRP developed computational phantoms representing the reference adult male and female and then calculated a set of dose conversion coefficients for various types of idealised external exposures. This paper focuses on the dose conversion coefficients for neutrons and investigates their relationship with the conversion coefficients of the protection and operational quantities of ICRP Publication 74. Contributing factors to the differences between these sets of conversion coefficients are discussed in terms of the changes in phantoms employed and the radiation and tissue weighting factors. This paper briefly reviews the reference computational phantoms and dose conversion coefficients for external exposures that were published jointly by ICRP and ICRU. Both these publications appeared as a consequence of the ICRP 2007 Recommendations; to implement these recommendations, the ICRP has developed reference computational phantoms representing the adult male and female. These phantoms are used to calculate reference dose conversion coefficients for external and internal sources. Using the reference phantoms and methodology consistent with the 2007 Recommendations, dose conversion coefficients for both effective doses and organ-absorbed doses for various types of idealised external exposures have been calculated. These data sets supersede the existing ICRP/ICRU data sets and expand the particle types and energy ranges. For neutrons, the new effective dose conversion coefficients become smaller compared with those in ICRP74, for energies below hundreds of keV. This is mainly
Extinction Coefficient of Gold Nanostars.
de Puig, Helena; Tam, Justina O; Yen, Chun-Wan; Gehrke, Lee; Hamad-Schifferli, Kimberly
2015-07-30
Gold nanostars (NStars) are highly attractive for biological applications due to their surface chemistry, facile synthesis and optical properties. Here, we synthesize NStars in HEPES buffer at different HEPES/Au ratios, producing NStars of different sizes and shapes, and therefore varying optical properties. We measure the extinction coefficient of the synthesized NStars at their maximum surface plasmon resonances (SPR), which range from 5.7 × 10 8 to 26.8 × 10 8 M -1 cm -1 . Measured values correlate with those obtained from theoretical models of the NStars using the discrete dipole approximation (DDA), which we use to simulate the extinction spectra of the nanostars. Finally, because NStars are typically used in biological applications, we conjugate DNA and antibodies to the NStars and calculate the footprint of the bound biomolecules.
Kerr scattering coefficients via isomonodromy
Energy Technology Data Exchange (ETDEWEB)
Cunha, Bruno Carneiro da [Departamento de Física, Universidade Federal de Pernambuco,50670-901, Recife, Pernambuco (Brazil); Novaes, Fábio [International Institute of Physics, Federal University of Rio Grande do Norte,Av. Odilon Gomes de Lima 1722, Capim Macio, Natal-RN 59078-400 (Brazil)
2015-11-23
We study the scattering of a massless scalar field in a generic Kerr background. Using a particular gauge choice based on the current conservation of the radial equation, we give a generic formula for the scattering coefficient in terms of the composite monodromy parameter σ between the inner and the outer horizons. Using the isomonodromy flow, we calculate σ exactly in terms of the Painlevé V τ-function. We also show that the eigenvalue problem for the angular equation (spheroidal harmonics) can be calculated using the same techniques. We use recent developments relating the Painlevé V τ-function to Liouville irregular conformal blocks to claim that this scattering problem is solved in the combinatorial sense, with known expressions for the τ-function near the critical points.
Comparing confidence intervals for Goodman and Kruskal's gamma coefficient
van der Ark, L.A.; van Aert, R.C.M.
2015-01-01
This study was motivated by the question which type of confidence interval (CI) one should use to summarize sample variance of Goodman and Kruskal's coefficient gamma. In a Monte-Carlo study, we investigated the coverage and computation time of the Goodman-Kruskal CI, the Cliff-consistent CI, the
Thermometric convection coefficients for rocket meteorological sensors (tables)
Staffanson, F. L.
1974-01-01
Values of the convective heat transfer coefficient h, and the recovery factor r, for miniature beads, fine wires, and films in rarefied air flow are shown. Data provide a standard reference for computing consistent operational corrections to rocket meteorological measurements, and for predicting the performance of existing and proposed sensor systems.
Generalized heat kernel coefficients for a new asymptotic expansion
International Nuclear Information System (INIS)
Osipov, Alexander A.; Hiller, Brigitte
2003-01-01
The method which allows for asymptotic expansion of the one-loop effective action W = lndetA is formulated. The positively defined elliptic operator A = U + M2 depends on the external classical fields taking values in the Lie algebra of the internal symmetry group G. Unlike the standard method of Schwinger - DeWitt, the more general case with the nongenerate mass matrix M = diag(m1, m2, ...) is considered. The first coefficients of the new asymptotic series are calculated and their relationship with the Seeley - DeWitt coefficients is clarified
Definition of global dispersion coefficients
International Nuclear Information System (INIS)
Naff, R.L.
1983-10-01
For estimation of a global longitudinal dispersivity at the Gorleben site, data available primarily consist of suites of geophysical logs from wells penetrating the Quaternary aquifer. A length scale for the principle aquifer at Gorleben is to be found. Samples are to be taken separately to estimate the variance in hydraulic conductivity (Taylor Analysis, Fickian dispersion process). (DG)
Factorization of Transport Coefficients in Macroporous Media
DEFF Research Database (Denmark)
Shapiro, Alexander; Stenby, Erling Halfdan
2000-01-01
We prove the fundamental theorem about factorization of the phenomenological coefficients for transport in macroporous media. By factorization we mean the representation of the transport coefficients as products of geometric parameters of the porous medium and the parameters characteristic...
View from Europe: stability, consistency or pragmatism
International Nuclear Information System (INIS)
Dunster, H.J.
1988-01-01
The last few years of this decade look like a period of reappraisal of radiation protection standards. The revised risk estimates from Japan will be available, and the United Nations Scientific Committee on the Effects of Atomic Radiation will be publishing new reports on biological topics. The International Commission on Radiological Protection (ICRP) has started a review of its basic recommendations, and the new specification for dose equivalent in radiation fields of the International Commission on Radiation Units and Measurements (ICRU) will be coming into use. All this is occurring at a time when some countries are still trying to catch up with committed dose equivalent and the recently recommended change in the value of the quality factor for neutrons. In Europe, the problems of adapting to new ICRP recommendations are considerable. The European Community, including 12 states and nine languages, takes ICRP recommendations as a basis and develops council directives that are binding on member states, which have then to arrange for their own regulatory changes. Any substantial adjustments could take 5 y or more to work through the system. Clearly, the regulatory preference is for stability. Equally clearly, trade unions and public interest groups favor a rapid response to scientific developments (provided that the change is downward). Organizations such as the ICRP have to balance their desire for internal consistency and intellectual purity against the practical problems of their clients in adjusting to change. This paper indicates some of the changes that might be necessary over the next few years and how, given a pragmatic approach, they might be accommodated in Europe without too much regulatory confusion
Bounds and Estimates for Transport Coefficients of Random and Porous Media with High Contrasts
International Nuclear Information System (INIS)
Berryman, J G
2004-01-01
Bounds on transport coefficients of random polycrystals of laminates are presented, including the well-known Hashin-Shtrikman bounds and some newly formulated bounds involving two formation factors for a two-component porous medium. Some new types of self-consistent estimates are then formulated based on the observed analytical structure both of these bounds and also of earlier self-consistent estimates (of the CPA or coherent potential approximation type). A numerical study is made, assuming first that the internal structure (i.e., the laminated grain structure) is not known, and then that it is known. The purpose of this aspect of the study is to attempt to quantify the differences in the predictions of properties of a system being modeled when such organized internal structure is present in the medium but detailed spatial correlation information may or (more commonly) may not be available. Some methods of estimating formation factors from data are also presented and then applied to a high-contrast fluid-permeability data set. Hashin-Shtrikman bounds are found to be very accurate estimates for low contrast heterogeneous media. But formation factor lower bounds are superior estimates for high contrast situations. The new self-consistent estimators also tend to agree better with data than either the bounds or the CPA estimates, which themselves tend to overestimate values for high contrast conducting composites
Kinetic coefficients for the biological treatment of tannery wastewater
International Nuclear Information System (INIS)
Haydar, S.
2008-01-01
Determination of kinetic coefficients for a particular wastewater is imperative for the rational design of biological treatment-facilities. The present study was undertaken with the objective of finding out kinetic coefficients for tannery wastewater. A bench-scale model of aerated lagoon, consisting of an aeration tank and final clarifier, was use to conduct the studies. The model was operated continuously for 96 days, by varying the detention times from 3 to 9 days. Influent for the aerated lagoon was settled tannery wastewater. Biochemical oxygen demand (BOD) of the influent and effluent and the mixed-liquor suspended solids (MLSS) of aeration tank were determined at various detention-times so as to generate data for kinetic coefficients. The kinetic coefficients k, Ks, Y and Ed were found to be 3.125 day/sup -1/, 488 mg/L, 0.64 and 0.035 day/sup -1/ respectively. Overall rate-constant of BOD, removal 'K' was also determined and was found to be 1.43 day/sup -1/. Kinetic coefficients were determined, at mean reactor-temperature of 30.2 degree C. These coefficients may be utilized for the design of biological-treatment facilities for tannery wastewater. (author)
Sun, Wei; Chou, Chih-Ping; Stacy, Alan W; Ma, Huiyan; Unger, Jennifer; Gallaher, Peggy
2007-02-01
Cronbach's a is widely used in social science research to estimate the internal consistency of reliability of a measurement scale. However, when items are not strictly parallel, the Cronbach's a coefficient provides a lower-bound estimate of true reliability, and this estimate may be further biased downward when items are dichotomous. The estimation of standardized Cronbach's a for a scale with dichotomous items can be improved by using the upper bound of coefficient phi. SAS and SPSS macros have been developed in this article to obtain standardized Cronbach's a via this method. The simulation analysis showed that Cronbach's a from upper-bound phi might be appropriate for estimating the real reliability when standardized Cronbach's a is problematic.
Consistent biokinetic models for the actinide elements
International Nuclear Information System (INIS)
Leggett, R.W.
2001-01-01
The biokinetic models for Th, Np, Pu, Am and Cm currently recommended by the International Commission on Radiological Protection (ICRP) were developed within a generic framework that depicts gradual burial of skeletal activity in bone volume, depicts recycling of activity released to blood and links excretion to retention and translocation of activity. For other actinide elements such as Ac, Pa, Bk, Cf and Es, the ICRP still uses simplistic retention models that assign all skeletal activity to bone surface and depicts one-directional flow of activity from blood to long-term depositories to excreta. This mixture of updated and older models in ICRP documents has led to inconsistencies in dose estimates and interpretation of bioassay for radionuclides with reasonably similar biokinetics. This paper proposes new biokinetic models for Ac, Pa, Bk, Cf and Es that are consistent with the updated models for Th, Np, Pu, Am and Cm. The proposed models are developed within the ICRP's generic model framework for bone-surface-seeking radionuclides, and an effort has been made to develop parameter values that are consistent with results of comparative biokinetic data on the different actinide elements. (author)
Anomalous Seebeck coefficient in boron carbides
International Nuclear Information System (INIS)
Aselage, T.L.; Emin, D.; Wood, C.; Mackinnon, I.D.R.; Howard, I.A.
1987-01-01
Boron carbides exhibit an anomalously large Seebeck coefficient with a temperature coefficient that is characteristic of polaronic hopping between inequivalent sites. The inequivalence in the sites is associated with disorder in the solid. The temperature dependence of the Seebeck coefficient for materials prepared by different techniques provides insight into the nature of the disorder
Standards for Standardized Logistic Regression Coefficients
Menard, Scott
2011-01-01
Standardized coefficients in logistic regression analysis have the same utility as standardized coefficients in linear regression analysis. Although there has been no consensus on the best way to construct standardized logistic regression coefficients, there is now sufficient evidence to suggest a single best approach to the construction of a…
Soccer Ball Lift Coefficients via Trajectory Analysis
Goff, John Eric; Carre, Matt J.
2010-01-01
We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin…
Symmetry chains and adaptation coefficients
International Nuclear Information System (INIS)
Fritzer, H.P.; Gruber, B.
1985-01-01
Given a symmetry chain of physical significance it becomes necessary to obtain states which transform properly with respect to the symmetries of the chain. In this article we describe a method which permits us to calculate symmetry-adapted quantum states with relative ease. The coefficients for the symmetry-adapted linear combinations are obtained, in numerical form, in terms of the original states of the system and can thus be represented in the form of numerical tables. In addition, one also obtains automatically the matrix elements for the operators of the symmetry groups which are involved, and thus for any physical operator which can be expressed either as an element of the algebra or of the enveloping algebra. The method is well suited for computers once the physically relevant symmetry chain, or chains, have been defined. While the method to be described is generally applicable to any physical system for which semisimple Lie algebras play a role we choose here a familiar example in order to illustrate the method and to illuminate its simplicity. We choose the nuclear shell model for the case of two nucleons with orbital angular momentum l = 1. While the states of the entire shell transform like the smallest spin representation of SO(25) we restrict our attention to its subgroup SU(6) x SU(2)/sub T/. We determine the symmetry chains which lead to total angular momentum SU(2)/sub J/ and obtain the symmetry-adapted states for these chains
Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS
Directory of Open Access Journals (Sweden)
Liao Hsuan-Yu
2016-01-01
Full Text Available The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05. An empirical model, consisting of the molecular weight and the polarizability, was developed to appropriately predict the partition coefficients of organic compounds. The empirical model for estimating the PDMS-gas partition coefficient will contribute to the practical applications of the SPME technique.
Partially linear varying coefficient models stratified by a functional covariate
Maity, Arnab
2012-10-01
We consider the problem of estimation in semiparametric varying coefficient models where the covariate modifying the varying coefficients is functional and is modeled nonparametrically. We develop a kernel-based estimator of the nonparametric component and a profiling estimator of the parametric component of the model and derive their asymptotic properties. Specifically, we show the consistency of the nonparametric functional estimates and derive the asymptotic expansion of the estimates of the parametric component. We illustrate the performance of our methodology using a simulation study and a real data application.
Local carbon diffusion coefficient measurement in the S-1 spheromak
International Nuclear Information System (INIS)
Mayo, R.M.; Levinton, F.M.; Meyerhofer, D.D.; Chu, T.K.; Paul, S.F.; Yamada, M.
1988-10-01
The local carbon diffusion coefficient was measured in the S - 1 spheromak by detecting the radial spread of injected carbon impurity. The radial impurity density profile is determined by the balance of ionization and diffusion. Using measured local electron temperature T/sub e/ and density n/sub e/, the ionization rate is determined from which the particle diffusion coefficient is inferred. The results found in this work are consistent with Bohm diffusion. The absolute magnitude of D/sub /perpendicular// was determined to be (4/approximately/6) /times/ D/sub Bohm/. 25 refs., 13 figs., 2 tabs
Energy coefficients for a propeller series
DEFF Research Database (Denmark)
Olsen, Anders Smærup
2004-01-01
The efficiency for a propeller is calculated by energy coefficients. These coefficients are related to four types of losses, i.e. the axial, the rotational, the frictional, and the finite blade number loss, and one gain, i.e. the axial gain. The energy coefficients are derived by use...... of the potential theory with the propeller modelled as an actuator disk. The efficiency based on the energy coefficients is calculated for a propeller series. The results show a good agreement between the efficiency based on the energy coefficients and the efficiency obtained by a vortex-lattice method....
International Nuclear Information System (INIS)
Shiles, E.; Sasaki, T.; Inokuti, M.; Smith, D.Y.
1980-01-01
An iterative, self-consistent procedure for the Kramers-Kronig analysis of data from reflectance, ellipsometric, transmission, and electron-energy-loss measurements is presented. This procedure has been developed for practical dispersion analysis since experimentally no single optical function can be readily measured over the entire range of frequencies as required by the Kramers-Kronig relations. The present technique is applied to metallic aluminum as an example. The results are then examined for internal consistency and for systematic errors by various optical sum rules. The present procedure affords a systematic means of preparing a self-consistent set of optical functions provided some optical or energy-loss data are available in all important spectral regions. The analysis of aluminum discloses that currently available data exhibit an excess oscillator strength, apparently in the vicinity of the L edge. A possible explanation is a systematic experimental error in the absorption-coefficient measurements resulting from surface layers: possibly oxides: present in thin-film transmission samples. A revised set of optical functions has been prepared by an ad hoc reduction of the reported absorption coefficient above the L edge by 14%. These revised data lead to a total oscillator strength consistent with the known electron density and are in agreement with dc-conductivity and stopping-power measurements as well as with absorption coefficients inferred from the cross sections of neighboring elements in the periodic table. The optical functions resulting from this study show evidence for both the redistribution of oscillator strength between energy levels and the effects on real transitions of the shielding of conduction electrons by virtual processes in the core states
DEFF Research Database (Denmark)
Kock, Anders Bredahl
2016-01-01
We show that the adaptive Lasso is oracle efficient in stationary and nonstationary autoregressions. This means that it estimates parameters consistently, selects the correct sparsity pattern, and estimates the coefficients belonging to the relevant variables at the same asymptotic efficiency...
International Nuclear Information System (INIS)
Li Longjian; Liu Hongtao; Cui Wenzhi
2007-01-01
The conjugated heat transfer of natural convection in pool with internal heat source and the forced convection in the tube was analyzed, and the corresponding three-dimensional physical and mathematical model was proposed. A control volume based finite element method was employed to solve numerically the problem. The computations were performed for different internal heat source intensity of the pool and the different flow velocity in the tube. The computed heat transfer coefficients on the inner and outer wall showed well consistency of those calculated with the empirical correlations. Compared with the measured total heat transfer coefficients between the fluids in and out of the tube, the computed ones showed also the well consistency, which implied that the numerical model proposed in this paper was reliable. The research results revealed that the total heat transfer coefficients between the fluids were strongly affected by the internal heat source intensity of the pool liquid and the flow velocity in the tube. (authors)
Structural covariance networks across healthy young adults and their consistency.
Guo, Xiaojuan; Wang, Yan; Guo, Taomei; Chen, Kewei; Zhang, Jiacai; Li, Ke; Jin, Zhen; Yao, Li
2015-08-01
To investigate structural covariance networks (SCNs) as measured by regional gray matter volumes with structural magnetic resonance imaging (MRI) from healthy young adults, and to examine their consistency and stability. Two independent cohorts were included in this study: Group 1 (82 healthy subjects aged 18-28 years) and Group 2 (109 healthy subjects aged 20-28 years). Structural MRI data were acquired at 3.0T and 1.5T using a magnetization prepared rapid-acquisition gradient echo sequence for these two groups, respectively. We applied independent component analysis (ICA) to construct SCNs and further applied the spatial overlap ratio and correlation coefficient to evaluate the spatial consistency of the SCNs between these two datasets. Seven and six independent components were identified for Group 1 and Group 2, respectively. Moreover, six SCNs including the posterior default mode network, the visual and auditory networks consistently existed across the two datasets. The overlap ratios and correlation coefficients of the visual network reached the maximums of 72% and 0.71. This study demonstrates the existence of consistent SCNs corresponding to general functional networks. These structural covariance findings may provide insight into the underlying organizational principles of brain anatomy. © 2014 Wiley Periodicals, Inc.
New Insights into Signed Path Coefficient Granger Causality Analysis.
Zhang, Jian; Li, Chong; Jiang, Tianzi
2016-01-01
Granger causality analysis, as a time series analysis technique derived from econometrics, has been applied in an ever-increasing number of publications in the field of neuroscience, including fMRI, EEG/MEG, and fNIRS. The present study mainly focuses on the validity of "signed path coefficient Granger causality," a Granger-causality-derived analysis method that has been adopted by many fMRI researches in the last few years. This method generally estimates the causality effect among the time series by an order-1 autoregression, and defines a positive or negative coefficient as an "excitatory" or "inhibitory" influence. In the current work we conducted a series of computations from resting-state fMRI data and simulation experiments to illustrate the signed path coefficient method was flawed and untenable, due to the fact that the autoregressive coefficients were not always consistent with the real causal relationships and this would inevitablely lead to erroneous conclusions. Overall our findings suggested that the applicability of this kind of causality analysis was rather limited, hence researchers should be more cautious in applying the signed path coefficient Granger causality to fMRI data to avoid misinterpretation.
Numerical study of effects of accommodation coefficients on slip phenomena
Energy Technology Data Exchange (ETDEWEB)
Choi, Young Jae; Kwon, Oh Joon [KAIST, Daejeon (Korea, Republic of)
2015-05-15
An unstructured mesh Navier-Stokes solver employing a Maxwell slip boundary condition was developed. The present flow solver was applied to the simulation of flows around an axisymmetric hollow cylinder in a Mach 10.4 free stream, known as Calspan-UB Research Center (CUBRC) Run 14 case, and the velocity slip and the temperature jump on the cylinder surface were investigated. The effect of tangential momentum and thermal accommodation coefficients used in the Maxwell condition was also investigated by adjusting their values. The results show that the reverse flow region is developed on the body surface due to the interaction between the shock and the boundary layer. Also, the shock impingement makes pressure high. The flow properties on the surface agree well with the experimental data, and the velocity slip and the temperature jump vary consistently with the local Knudsen number change. The accommodation coefficients affect the slip phenomena and the size of the flow region. The slip phenomena become larger when both tangential momentum and thermal accommodation coefficients are decreased. However, the range of the reverse flow region decreases when the momentum accommodation coefficient is decreased. The characteristics of the momentum and thermal accommodation coefficients also are overlapped when they are altered together.
Exact coefficients for higher dimensional operators with sixteen supersymmetries
Energy Technology Data Exchange (ETDEWEB)
Chen, Wei-Ming [Department of Physics and Astronomy, National Taiwan University,Taipei 10617, Taiwan, R.O.C. (China); Huang, Yu-tin [Department of Physics and Astronomy, National Taiwan University,Taipei 10617, Taiwan, R.O.C. (China); School of Natural Sciences, Institute for Advanced Study,Princeton, NJ 08540 (United States); Wen, Congkao [INFN Sezione di Roma “Tor Vergata' ,Via della Ricerca Scientifica, 00133 Roma (Italy)
2015-09-15
We consider constraints on higher-dimensional operators for supersymmetric effective field theories. In four dimensions with maximal supersymmetry and SU(4) R-symmetry, we demonstrate that the coefficients of abelian operators F{sup n} with MHV helicity configurations must satisfy a recursion relation, and are completely determined by that of F{sup 4}. As the F{sup 4} coefficient is known to be one-loop exact, this allows us to derive exact coefficients for all such operators. We also argue that the results are consistent with the SL(2,Z) duality symmetry. Breaking SU(4) to Sp(4), in anticipation for the Coulomb branch effective action, we again find an infinite class of operators whose coefficients are determined exactly. We also consider three-dimensional N=8 as well as six-dimensional N=(2,0),(1,0) and (1,1) theories. In all cases, we demonstrate that the coefficient of dimension-six operator must be proportional to the square of that of dimension-four.
Condensation coefficient of water in a weak condensation state
International Nuclear Information System (INIS)
Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo
2008-01-01
The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].
Condensation coefficient of water in a weak condensation state
Kobayashi, Kazumichi; Watanabe, Shunsuke; Yamano, Daigo; Yano, Takeru; Fujikawa, Shigeo
2008-07-01
The condensation coefficient of water at a vapor-liquid interface is determined by combining shock tube experiments and numerical simulations of the Gaussian-BGK Boltzmann equation. The time evolution in thickness of a liquid film, which is formed on the shock tube endwall behind the shock wave reflected at the endwall, is measured with an optical interferometer consisting of the physical beam and the reference one. The reference beam is utilized to eliminate systematic noises from the physical beam. The growth rate of the film is evaluated from the measured time evolution and it is incorporated into the kinetic boundary condition for the Boltzmann equation. From a numerical simulation using the boundary condition, the condensation coefficient of water is uniquely deduced. The results show that, in a condition of weak condensation near a vapor-liquid equilibrium state, the condensation coefficient of water is almost equal to the evaporation coefficient estimated by molecular dynamics simulations near a vapor-liquid equilibrium state and it decreases as the system becomes a nonequilibrium state. The condensation coefficient of water is nearly identical with that of methanol [Mikami, S., Kobayashi, K., Ota, T., Fujikawa, S., Yano, T., Ichijo, M., 2006. Molecular gas dynamics approaches to interfacial phenomena accompanied with condensation. Exp. Therm. Fluid Sci. 30, 795-800].
Criticality coefficient calculation for a small PWR using Monte Carlo Transport Code
Energy Technology Data Exchange (ETDEWEB)
Trombetta, Debora M.; Su, Jian, E-mail: dtrombetta@nuclear.ufrj.br, E-mail: sujian@nuclear.ufrj.br [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil); Chirayath, Sunil S., E-mail: sunilsc@tamu.edu [Department of Nuclear Engineering and Nuclear Security Science and Policy Institute, Texas A and M University, TX (United States)
2015-07-01
Computational models of reactors are increasingly used to predict nuclear reactor physics parameters responsible for reactivity changes which could lead to accidents and losses. In this work, preliminary results for criticality coefficient calculation using the Monte Carlo transport code MCNPX were presented for a small PWR. The computational modeling developed consists of the core with fuel elements, radial reflectors, and control rods inside a pressure vessel. Three different geometries were simulated, a single fuel pin, a fuel assembly and the core, with the aim to compare the criticality coefficients among themselves.The criticality coefficients calculated were: Doppler Temperature Coefficient, Coolant Temperature Coefficient, Coolant Void Coefficient, Power Coefficient, and Control Rod Worth. The coefficient values calculated by the MCNP code were compared with literature results, showing good agreement with reference data, which validate the computational model developed and allow it to be used to perform more complex studies. Criticality Coefficient values for the three simulations done had little discrepancy for almost all coefficients investigated, the only exception was the Power Coefficient. Preliminary results presented show that simple modelling as a fuel assembly can describe changes at almost all the criticality coefficients, avoiding the need of a complex core simulation. (author)
A drying coefficient for building materials
DEFF Research Database (Denmark)
Scheffler, Gregor Albrecht; Plagge, Rudolf
2009-01-01
coefficient is defined which can be determined based on measured drying data. The correlation of this coefficient with the water absorption and the vapour diffusion coefficient is analyzed and its additional information content is critically challenged. As result, a drying coefficient has been derived......The drying experiment is an important element of the hygrothermal characterisation of building materials. Contrary to other moisture transport experiments as the vapour diffusion and the water absorption test, it is until now not possible to derive a simple coefficient for the drying. However......, in many cases such a coefficient would be highly appreciated, e.g. in interaction of industry and research or for the distinction and selection of suitable building materials throughout design and practise. This article first highlights the importance of drying experiments for hygrothermal...
Prediction of Partition Coefficients of Organic Compounds for SPME/PDMS
Liao Hsuan-Yu; Huang Miao-Ling; Lu Yu-Ting; Chao Keh-Ping
2016-01-01
The partition coefficients of 51 organic compounds between SPME/PDMS and gas were compiled from the literature sources in this study. The effect of physicochemical properties and descriptors on the partitioning process of partition coefficients was explicated by the correlation analysis. The PDMS-gas partition coefficients were well correlated to the molecular weight of organic compounds (r = 0.832, p < 0.05). An empirical model, consisting of the molecular weight and the polarizability, was ...
Apparatus for measurement of coefficient of friction
Slifka, A. J.; Siegwarth, J. D.; Sparks, L. L.; Chaudhuri, Dilip K.
1990-01-01
An apparatus designed to measure the coefficient of friction in certain controlled atmospheres is described. The coefficient of friction observed during high-load tests was nearly constant, with an average value of 0.56. This value is in general agreement with that found in the literature and also with the initial friction coefficient value of 0.67 measured during self-mated friction of 440C steel in an oxygen environment.
New definition of the cell diffusion coefficient
International Nuclear Information System (INIS)
Koehler, P.
1975-01-01
As was shown in a recent work by Gelbard, the usually applied Benoist definition of the cell diffusion coefficient gives two different values if two different definitions of the cell are made. A new definition is proposed that preserves the neutron balance for the homogenized lattice and that is independent of the cell definition. The resulting diffusion coefficient is identical with the main term of Benoist's diffusion coefficient
Toward a consistent model for glass dissolution
International Nuclear Information System (INIS)
Strachan, D.M.; McGrail, B.P.; Bourcier, W.L.
1994-01-01
Understanding the process of glass dissolution in aqueous media has advanced significantly over the last 10 years through the efforts of many scientists around the world. Mathematical models describing the glass dissolution process have also advanced from simple empirical functions to structured models based on fundamental principles of physics, chemistry, and thermodynamics. Although borosilicate glass has been selected as the waste form for disposal of high-level wastes in at least 5 countries, there is no international consensus on the fundamental methodology for modeling glass dissolution that could be used in assessing the long term performance of waste glasses in a geologic repository setting. Each repository program is developing their own model and supporting experimental data. In this paper, we critically evaluate a selected set of these structured models and show that a consistent methodology for modeling glass dissolution processes is available. We also propose a strategy for a future coordinated effort to obtain the model input parameters that are needed for long-term performance assessments of glass in a geologic repository. (author) 4 figs., tabs., 75 refs
Consistency of the tachyon warm inflationary universe models
International Nuclear Information System (INIS)
Zhang, Xiao-Min; Zhu, Jian-Yang
2014-01-01
This study concerns the consistency of the tachyon warm inflationary models. A linear stability analysis is performed to find the slow-roll conditions, characterized by the potential slow-roll (PSR) parameters, for the existence of a tachyon warm inflationary attractor in the system. The PSR parameters in the tachyon warm inflationary models are redefined. Two cases, an exponential potential and an inverse power-law potential, are studied, when the dissipative coefficient Γ = Γ 0 and Γ = Γ(φ), respectively. A crucial condition is obtained for a tachyon warm inflationary model characterized by the Hubble slow-roll (HSR) parameter ε H , and the condition is extendable to some other inflationary models as well. A proper number of e-folds is obtained in both cases of the tachyon warm inflation, in contrast to existing works. It is also found that a constant dissipative coefficient (Γ = Γ 0 ) is usually not a suitable assumption for a warm inflationary model
Transfer coefficients in ultracold strongly coupled plasma
Bobrov, A. A.; Vorob'ev, V. S.; Zelener, B. V.
2018-03-01
We use both analytical and molecular dynamic methods for electron transfer coefficients in an ultracold plasma when its temperature is small and the coupling parameter characterizing the interaction of electrons and ions exceeds unity. For these conditions, we use the approach of nearest neighbor to determine the average electron (ion) diffusion coefficient and to calculate other electron transfer coefficients (viscosity and electrical and thermal conductivities). Molecular dynamics simulations produce electronic and ionic diffusion coefficients, confirming the reliability of these results. The results compare favorably with experimental and numerical data from earlier studies.
Comparing linear probability model coefficients across groups
DEFF Research Database (Denmark)
Holm, Anders; Ejrnæs, Mette; Karlson, Kristian Bernt
2015-01-01
of the following three components: outcome truncation, scale parameters and distributional shape of the predictor variable. These results point to limitations in using linear probability model coefficients for group comparisons. We also provide Monte Carlo simulations and real examples to illustrate......This article offers a formal identification analysis of the problem in comparing coefficients from linear probability models between groups. We show that differences in coefficients from these models can result not only from genuine differences in effects, but also from differences in one or more...... these limitations, and we suggest a restricted approach to using linear probability model coefficients in group comparisons....
Experimental evaluation of heat transfer coefficients between radiant ceiling and room
DEFF Research Database (Denmark)
Causone, Francesco; Corgnati, Stefano P.; Filippi, Marco
2009-01-01
The heat transfer coefficients between radiant surfaces and room are influenced by several parameters: surfaces temperature distributions, internal gains, air movements. The aim of this paper is to evaluate the heat transfer coefficients between radiant ceiling and room in typical conditions...... of occupancy of an office or residential building. Internal gains were therefore simulated using heated cylinders and heat losses using cooled surfaces. Evaluations were developed by means of experimental tests in an environmental chamber. Heat transfer coefficient may be expressed separately for radiation...
Consistent Partial Least Squares Path Modeling via Regularization
Directory of Open Access Journals (Sweden)
Sunho Jung
2018-02-01
Full Text Available Partial least squares (PLS path modeling is a component-based structural equation modeling that has been adopted in social and psychological research due to its data-analytic capability and flexibility. A recent methodological advance is consistent PLS (PLSc, designed to produce consistent estimates of path coefficients in structural models involving common factors. In practice, however, PLSc may frequently encounter multicollinearity in part because it takes a strategy of estimating path coefficients based on consistent correlations among independent latent variables. PLSc has yet no remedy for this multicollinearity problem, which can cause loss of statistical power and accuracy in parameter estimation. Thus, a ridge type of regularization is incorporated into PLSc, creating a new technique called regularized PLSc. A comprehensive simulation study is conducted to evaluate the performance of regularized PLSc as compared to its non-regularized counterpart in terms of power and accuracy. The results show that our regularized PLSc is recommended for use when serious multicollinearity is present.
Resummed coefficient function for the shape function
Aglietti, U.
2001-01-01
We present a leading evaluation of the resummed coefficient function for the shape function. It is also shown that the coefficient function is short-distance-dominated. Our results allow relating the shape function computed on the lattice to the physical QCD distributions.
Problems with Discontinuous Diffusion/Dispersion Coefficients
Directory of Open Access Journals (Sweden)
Stefano Ferraris
2012-01-01
accurate on smooth solutions and based on a special numerical treatment of the diffusion/dispersion coefficients that makes its application possible also when such coefficients are discontinuous. Numerical experiments confirm the convergence of the numerical approximation and show a good behavior on a set of benchmark problems in two space dimensions.
Meta-Analysis of Coefficient Alpha
Rodriguez, Michael C.; Maeda, Yukiko
2006-01-01
The meta-analysis of coefficient alpha across many studies is becoming more common in psychology by a methodology labeled reliability generalization. Existing reliability generalization studies have not used the sampling distribution of coefficient alpha for precision weighting and other common meta-analytic procedures. A framework is provided for…
Alternatives to Pearson's and Spearman's Correlation Coefficients
Smarandache, Florentin
2008-01-01
This article presents several alternatives to Pearson's correlation coefficient and many examples. In the samples where the rank in a discrete variable counts more than the variable values, the mixtures that we propose of Pearson's and Spearman's correlation coefficients give better results.
Anomaly coefficients: Their calculation and congruences
International Nuclear Information System (INIS)
Braden, H.W.
1988-01-01
A new method for the calculation of anomaly coefficients is presented. For su(n) some explicit and general expressions are given for these. In particular, certain congruences are discovered and investigated among the leading anomaly coefficients. As an application of these congruences, the absence of global six-dimensional gauge anomalies is shown
Prediction of friction coefficients for gases
Taylor, M. F.
1969-01-01
Empirical relations are used for correlating laminar and turbulent friction coefficients for gases, with large variations in the physical properties, flowing through smooth tubes. These relations have been used to correlate friction coefficients for hydrogen, helium, nitrogen, carbon dioxide and air.
A gain-coefficient switched Alexandrite laser
International Nuclear Information System (INIS)
Lee, Chris J; Van der Slot, Peter J M; Boller, Klaus-J
2013-01-01
We report on a gain-coefficient switched Alexandrite laser. An electro-optic modulator is used to switch between high and low gain states by making use of the polarization dependent gain of Alexandrite. In gain-coefficient switched mode, the laser produces 85 ns pulses with a pulse energy of 240 mJ at a repetition rate of 5 Hz.
Helioseismic Solar Cycle Changes and Splitting Coefficients
Indian Academy of Sciences (India)
tribpo
Abstract. Using the GONG data for a period over four years, we have studied the variation of frequencies and splitting coefficients with solar cycle. Frequencies and even-order coefficients are found to change signi- ficantly with rising phase of the solar cycle. We also find temporal varia- tions in the rotation rate near the solar ...
Gini coefficient as a life table function
Directory of Open Access Journals (Sweden)
2003-06-01
Full Text Available This paper presents a toolkit for measuring and analyzing inter-individual inequality in length of life by Gini coefficient. Gini coefficient and four other inequality measures are defined on the length-of-life distribution. Properties of these measures and their empirical testing on mortality data suggest a possibility for different judgements about the direction of changes in the degree of inequality by using different measures. A new computational procedure for the estimation of Gini coefficient from life tables is developed and tested on about four hundred real life tables. The estimates of Gini coefficient are precise enough even for abridged life tables with the final age group of 85+. New formulae have been developed for the decomposition of differences between Gini coefficients by age and cause of death. A new method for decomposition of age-components into effects of mortality and composition of population by group is developed. Temporal changes in the effects of elimination of causes of death on Gini coefficient are analyzed. Numerous empirical examples show: Lorenz curves for Sweden, Russia and Bangladesh in 1995, proportional changes in Gini coefficient and four other measures of inequality for the USA in 1950-1995 and for Russia in 1959-2000. Further shown are errors of estimates of Gini coefficient when computed from various types of mortality data of France, Japan, Sweden and the USA in 1900-95, decompositions of the USA-UK difference in life expectancies and Gini coefficients by age and cause of death in 1997. As well, effects of elimination of major causes of death in the UK in 1951-96 on Gini coefficient, age-specific effects of mortality and educational composition of the Russian population on changes in life expectancy and Gini coefficient between 1979 and 1989. Illustrated as well are variations in life expectancy and Gini coefficient across 32 countries in 1996-1999 and associated changes in life expectancy and Gini
International Nuclear Information System (INIS)
Wang, H.-L.; Liu, B.
2014-01-01
This paper investigates what is the largest magnetoelectric (ME) coefficient of ME composites, and how to realize it. From the standpoint of energy conservation, a theoretical analysis is carried out on an imaginary lever structure consisting of a magnetostrictive phase, a piezoelectric phase, and a rigid lever. This structure is a generalization of various composite layouts for optimization on ME effect. The predicted theoretical ultimate ME coefficient plays a similar role as the efficiency of ideal heat engine in thermodynamics, and is used to evaluate the existing typical ME layouts, such as the parallel sandwiched layout and the serial layout. These two typical layouts exhibit ME coefficient much lower than the theoretical largest values, because in the general analysis the stress amplification ratio and the volume ratio can be optimized independently and freely, but in typical layouts they are dependent or fixed. To overcome this shortcoming and achieve the theoretical largest ME coefficient, a new design is presented. In addition, it is found that the most commonly used electric field ME coefficient can be designed to be infinitely large. We doubt the validity of this coefficient as a reasonable ME effect index and consider three more ME coefficients, namely the electric charge ME coefficient, the voltage ME coefficient, and the static electric energy ME coefficient. We note that the theoretical ultimate value of the static electric energy ME coefficient is finite and might be a more proper measure of ME effect
Determination of the surface drag coefficient
DEFF Research Database (Denmark)
Mahrt, L.; Vickers, D.; Sun, J.L.
2001-01-01
This study examines the dependence of the surface drag coefficient on stability, wind speed, mesoscale modulation of the turbulent flux and method of calculation of the drag coefficient. Data sets over grassland, sparse grass, heather and two forest sites are analyzed. For significantly unstable...... conditions, the drag coefficient does not depend systematically on z/L but decreases with wind speed for fixed intervals of z/L, where L is the Obukhov length. Even though the drag coefficient for weak wind conditions is sensitive to the exact method of calculation and choice of averaging time, the decrease...... of the drag coefficient with wind speed occurs for all of the calculation methods. A classification of flux calculation methods is constructed, which unifies the most common previous approaches. The roughness length corresponding to the usual Monin-Obukhov stability functions decreases with increasing wind...
Diffusion coefficients of paracetamol in aqueous solutions
International Nuclear Information System (INIS)
Ribeiro, Ana C.F.; Barros, Marisa C.F.; Veríssimo, Luís M.P.; Santos, Cecilia I.A.V.; Cabral, Ana M.T.D.P.V.; Gaspar, Gualter D.; Esteso, Miguel A.
2012-01-01
Highlights: ► Mutual diffusion coefficients of paracetamol in aqueous dilute solutions. ► Influence of the thermodynamic factors on the variation of their mutual diffusion coefficients. ► Estimation of the mutual limiting diffusion coefficients of the molecular, D m 0 , and ionized forms, D ± 0 , of this drug. - Abstract: Binary mutual diffusion coefficients measured by the Taylor dispersion method, for aqueous solutions of paracetamol (PA) at concentrations from (0.001 to 0.050) mol·dm −3 at T = 298.15 K, are reported. From the Nernst–Hartley equation and our experimental results, the limiting diffusion coefficient of this drug and its thermodynamic factors are estimated, thereby contributing in this way to a better understanding of the structure of such systems and of their thermodynamic behaviour in aqueous solution at different concentrations.
Estimation of the simple correlation coefficient.
Shieh, Gwowen
2010-11-01
This article investigates some unfamiliar properties of the Pearson product-moment correlation coefficient for the estimation of simple correlation coefficient. Although Pearson's r is biased, except for limited situations, and the minimum variance unbiased estimator has been proposed in the literature, researchers routinely employ the sample correlation coefficient in their practical applications, because of its simplicity and popularity. In order to support such practice, this study examines the mean squared errors of r and several prominent formulas. The results reveal specific situations in which the sample correlation coefficient performs better than the unbiased and nearly unbiased estimators, facilitating recommendation of r as an effect size index for the strength of linear association between two variables. In addition, related issues of estimating the squared simple correlation coefficient are also considered.
Techniques For Measuring Absorption Coefficients In Crystalline Materials
Klein, Philipp H.
1981-10-01
Absorption coefficients smaller than 0.001 cm-1 can, with more or less difficulty, be measured by several techniques. With diligence, all methods can be refined to permit measurement of absorption coefficients as small as 0.00001 cm-1. Spectral data are most readily obtained by transmission (spectrophotometric) methods, using multiple internal reflection to increase effective sample length. Emissivity measurements, requiring extreme care in the elimination of detector noise and stray light, nevertheless afford the most accessible spectral data in the 0.0001 to 0.00001 cm-1 range. Single-wavelength informa-tion is most readily obtained with modifications of laser calorimetry. Thermo-couple detection of energy absorbed from a laser beam is convenient, but involves dc amplification techniques and is susceptible to stray-light problems. Photoacoustic detection, using ac methods, tends to diminish errors of these types, but at some expense in experimental complexity. Laser calorimetry has been used for measurements of absorption coefficients as small as 0.000003 cm-1. Both transmission and calorimetric data, taken as functions of intensity, have been used for measurement of nonlinear absorption coefficients.
Is There a Future for Education Consistent with Agenda 21?
Smyth, John
1999-01-01
Discusses recent experiences in developing and implementing strategies for education consistent with the concept of sustainable development at two different levels: (1) the international level characterized by Agenda 21 along with the efforts of the United Nations Commission on Sustainable Development to foster its progress; and (2) the national…
Consistent treatment of one-body dynamics and collective fluctuations
International Nuclear Information System (INIS)
Pfitzner, A.
1986-09-01
We show how the residual coupling deltaV between collective and intrinsic motion induces correlations, which lead to fluctuations of the collective variables and to a redistribution of single-particle occupation numbers rho/sub α/. The evolution of rho/sub α/ and of the collective fluctuations is consistently described by a coupled system of equations, which accounts for the dependence of the transport coefficients on rho/sub α/, and for the dependence of the transition rates in the master equation on the collective variances. (author)
Tunneling in a self-consistent dynamic image potential
International Nuclear Information System (INIS)
Rudberg, B.G.R.; Jonson, M.
1991-01-01
We have calculated the self-consistent effective potential for an electron tunneling through a square barrier while interacting with surface plasmons. This potential reduces to the classical image potential in the static limit. In the opposite limit, when the ''velocity'' of the tunneling electron is large, it reduces to the unperturbed square-barrier potential. For a wide variety of parameters the dynamic effects on the transmission coefficient T=|t 2 | can, for instance, be related to the Buettiker-Landauer traversal time for tunneling, given by τ BL =ℎ|d lnt/dV|
Internal conversion theory of gamma radiation in unfilled atomic shells
International Nuclear Information System (INIS)
Anderson, Eh.M.; Trusov, V.F.; Ehglajs, M.O.
1980-01-01
The internal conversion theory of gamma radiation in unfilled shells, when the atom is in a state with certain energy and momentum, is considered. A formula for the conversion coefficient between the atom and ion levels is obtained. This coefficient turns to be dependent on genealogic characteristics of the atom. It is discussed when the conversion coefficients are proportional to the numbers of filling subshells in the atom. Exact calculations have been carried out in the multiconfigurational approximation taking into account intermediate coupling for the d-shell of the Fe atom Single-electron radial wave functions have been calculated on the basis of the relativistic method of the Hartree-Fock-Dirak self-consistent field. Conversion coefficients on certain subshells as well as submatrix elements of the production operator are calculated. The electric coefficient of internal conversion (CIC) in the calculation for one electron does not depend on spin orientation. That is why the electric CIC from the level will not depend on filling number distribution by subshells. For magnetic CIC the dependence on the atom state is significant. Using multiconfiguration basis for calculating energy matrix and its succeeding diagonalization means the account of the intermediate coupling type, which takes place for the unfilled shells
A Time consistent model for monetary value of man-sievert
International Nuclear Information System (INIS)
Na, S.H.; Kim, Sun G.
2008-01-01
Full text: Performing a cost-benefit analysis to establish optimum levels of radiation protection under the ALARA principle, we introduce a discrete stepwise model to evaluate man-sievert monetary value of Korea. The model formula, which is unique and country-specific, is composed of GDP, the nominal risk coefficient for cancer and hereditary effects, the aversion factor against radiation exposure, and the average life expectancy. Unlike previous researches on alpha-value assessment, we showed different alpha values optimized with respect to various ranges of individual dose, which would be more realistic and applicable to the radiation protection area. Employing economically constant term of GDP we showed the real values of man-sievert by year, which should be consistent in time series comparison even under price level fluctuation. GDP deflators of an economy have to be applied to measure one's own consistent value of radiation protection by year. In addition, we recommend that the concept of purchasing power parity should be adopted if it needs international comparison of alpha values in real terms. Finally, we explain the way that this stepwise model can be generalized simply to other countries without normalizing any country-specific factors. (author)
Transport coefficients of strongly interacting matter
International Nuclear Information System (INIS)
Heckmann, Klaus
2011-01-01
In this thesis, we investigate the dissipative transport phenomena of strongly interacting matter. The special interest is in the shear viscosity and its value divided by entropy density. The performed calculations are based on effective models for Quantum Chromodynamics, mostly focused on the 2-flavor Nambu-Jona-Lasinio model. This allows us to study the hadronic sector as well as the quark sector within one single model. We expand the models up to next-to-leading order in inverse numbers of colors. We present different possibilities of calculating linear transport coefficients and give an overview over qualitative properties as well as over recent ideas concerning ideal fluids. As present methods are not able to calculate the quark two-point function in Minkowski space-time in the self-consistent approximation scheme of the Nambu-Jona-Lasinio model, a new method for this purpose is developed. This self-energy parametrization method is applied to the expansion scheme, yielding the quark spectral function with meson back-coupling effects. The usage of this spectral function in the transport calculation is only one result of this work. We also test the application of different transport approaches in the NJL model, and find an interesting behavior of the shear viscosity at the critical end point of the phase diagram. We also use the NJL model to calculate the viscosity of a pion gas in the dilute regime. After an analysis of other models for pions and their interaction, we find that the NJL-result leads to an important modification of transport properties in comparison with the calculations which purely rely on pion properties in the vacuum. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Takebe, Shinichi; Abe, Masayoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
2001-03-01
The distribution coefficient is very important parameter for environmental impact assessment on the disposal of radioactive waste arising from research institutes. The literature survey in the country was mainly carried out for the purpose of selecting the reasonable distribution coefficient value on the utilization of this value in the safety evaluation. This report was arranged much informations on the distribution coefficient for inputting to the database for each literature, and was summarized as a literature information data on the distribution coefficient. (author)
Variation in aerodynamic coefficients with altitude
Directory of Open Access Journals (Sweden)
Faiza Shahid
Full Text Available Precise aerodynamics performance prediction plays key role for a flying vehicle to get its mission completed within desired accuracy. Aerodynamic coefficients for same Mach number can be different at different altitude due to difference in Reynolds number. Prediction of these aerodynamics coefficients can be made through experiments, analytical solution or Computational Fluid Dynamics (CFD. Advancements in computational power have generated the concept of using CFD as a virtual Wind Tunnel (WT, hence aerodynamic performance prediction in present study is based upon CFD (numerical test rig. Simulations at different altitudes for a range of Mach numbers with zero angle of attack are performed to predict axial force coefficient behavior with altitude (Reynolds number. Similar simulations for a fixed Mach number â3â and a range of angle of attacks are also carried out to envisage the variation in normal force and pitching moment coefficients with altitude (Reynolds number. Results clearly depict that the axial force coefficient is a function of altitude (Reynolds number and increase as altitude increases, especially for subsonic region. Variation in axial force coefficient with altitude (Reynolds number slightly increases for larger values of angle of attacks. Normal force and pitching moment coefficients do not depend on altitude (Reynolds number at smaller values of angle of attacks but show slight decrease as altitude increases. Present study suggests that variation of normal force and pitching moment coefficients with altitude can be neglected but the variation of axial force coefficient with altitude should be considered for vehicle fly in dense atmosphere. It is recommended to continue this study to more complex configurations for various Mach numbers with side slip and real gas effects. Keywords: Mach number, Reynolds number, Blunt body, Altitude effect, Angle of attacks
Variation in aerodynamic coefficients with altitude
Shahid, Faiza; Hussain, Mukkarum; Baig, Mirza Mehmood; Haq, Ihtram ul
Precise aerodynamics performance prediction plays key role for a flying vehicle to get its mission completed within desired accuracy. Aerodynamic coefficients for same Mach number can be different at different altitude due to difference in Reynolds number. Prediction of these aerodynamics coefficients can be made through experiments, analytical solution or Computational Fluid Dynamics (CFD). Advancements in computational power have generated the concept of using CFD as a virtual Wind Tunnel (WT), hence aerodynamic performance prediction in present study is based upon CFD (numerical test rig). Simulations at different altitudes for a range of Mach numbers with zero angle of attack are performed to predict axial force coefficient behavior with altitude (Reynolds number). Similar simulations for a fixed Mach number '3' and a range of angle of attacks are also carried out to envisage the variation in normal force and pitching moment coefficients with altitude (Reynolds number). Results clearly depict that the axial force coefficient is a function of altitude (Reynolds number) and increase as altitude increases, especially for subsonic region. Variation in axial force coefficient with altitude (Reynolds number) slightly increases for larger values of angle of attacks. Normal force and pitching moment coefficients do not depend on altitude (Reynolds number) at smaller values of angle of attacks but show slight decrease as altitude increases. Present study suggests that variation of normal force and pitching moment coefficients with altitude can be neglected but the variation of axial force coefficient with altitude should be considered for vehicle fly in dense atmosphere. It is recommended to continue this study to more complex configurations for various Mach numbers with side slip and real gas effects.
Modification of van La ar activity coefficient model
International Nuclear Information System (INIS)
Vakili-Nezhaad, G. R.; Modarress, H.; Mansoori, G. A.
2001-01-01
Based on statistical and mechanical arguments, the original van La ar activity coefficient model has been improved by reasonable assumptions. This modifications has been done by replacing the van der Waals equation of state with the Redlich-K wong equation of state in the formulation of van La ar with consistent mixing rules for the energy and volume parameters of this equation of state (a mix , b mix ). Other equations of state, such as the Soave modification of the Redlich-K wong equation of state, P eng-Robinson and Mohsen-Nia, Modarress and Mansoori equations of state, have been introduced in the formulation of van La ar for the activity coefficients of the components present in the binary liquid mixtures, and their effects on the accuracy of the resultant activity coefficient models have been examined. The results of these revised models have been compared with the experimental data and it was found that the Redlich-K wong equation of state with the van der Waals mixing rules for the volume and energy parameters of this equation, is the best choice among these equations of state. In addition, it can improve the original van La ar activity coefficient model and, therefore a better agreement with the experimental data is obtained
Heat transfer coefficient for boiling carbon dioxide
DEFF Research Database (Denmark)
Knudsen, Hans Jørgen Høgaard; Jensen, Per Henrik
1998-01-01
Heat transfer coefficient and pressure drop for boiling carbon dioxide (R744) flowing in a horizontal pipe has been measured. The calculated heat transfer coeeficient has been compared with the Chart correlation of Shah. The Chart Correlation predits too low heat transfer coefficient but the ratio...... between the measured and the calculated heat transfer coefficient is nearly constant and equal 1.9. With this factor the correlation predicts the measured data within 14% (RMS). The pressure drop is of the same order as the measuring uncertainty and the pressure drop has not been compared with correlation's....
Virial Coefficients for the Liquid Argon
Korth, Micheal; Kim, Saesun
2014-03-01
We begin with a geometric model of hard colliding spheres and calculate probability densities in an iterative sequence of calculations that lead to the pair correlation function. The model is based on a kinetic theory approach developed by Shinomoto, to which we added an interatomic potential for argon based on the model from Aziz. From values of the pair correlation function at various values of density, we were able to find viral coefficients of liquid argon. The low order coefficients are in good agreement with theoretical hard sphere coefficients, but appropriate data for argon to which these results might be compared is difficult to find.
Soccer ball lift coefficients via trajectory analysis
International Nuclear Information System (INIS)
Goff, John Eric; Carre, Matt J
2010-01-01
We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.
Soccer ball lift coefficients via trajectory analysis
Energy Technology Data Exchange (ETDEWEB)
Goff, John Eric [Department of Physics, Lynchburg College, Lynchburg, VA 24501 (United States); Carre, Matt J, E-mail: goff@lynchburg.ed [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)
2010-07-15
We performed experiments in which a soccer ball was launched from a machine while two high-speed cameras recorded portions of the trajectory. Using the trajectory data and published drag coefficients, we extracted lift coefficients for a soccer ball. We determined lift coefficients for a wide range of spin parameters, including several spin parameters that have not been obtained by today's wind tunnels. Our trajectory analysis technique is not only a valuable tool for professional sports scientists, it is also accessible to students with a background in undergraduate-level classical mechanics.
Consistency Anchor Formalization and Correctness Proofs
Miguel, Correia; Bessani, Alysson
2014-01-01
This is report contains the formal proofs for the techniques for increasing the consistency of cloud storage as presented in "Bessani et al. SCFS: A Cloud-backed File System. Proc. of the 2014 USENIX Annual Technical Conference. June 2014." The consistency anchor technique allows one to increase the consistency provided by eventually consistent cloud storage services like Amazon S3. This technique has been used in the SCFS (Shared Cloud File System) cloud-backed file system for solving rea...
Directory of Open Access Journals (Sweden)
Ryoichi Chiba
2018-01-01
Full Text Available An analytical solution is derived for one-dimensional transient heat conduction in a composite slab consisting of n layers, whose heat transfer coefficient on an external boundary is an arbitrary function of time. The composite slab, which has thermal contact resistance at n-1 interfaces, as well as an arbitrary initial temperature distribution and internal heat generation, convectively exchanges heat at the external boundaries with two different time-varying surroundings. To obtain the analytical solution, the shifting function method is first used, which yields new partial differential equations under conventional types of external boundary conditions. The solution for the derived differential equations is then obtained by means of an orthogonal expansion technique. Numerical calculations are performed for two composite slabs, whose heat transfer coefficient on the heated surface is either an exponential or a trigonometric function of time. The numerical results demonstrate the effects of temporal variations in the heat transfer coefficient on the transient temperature field of composite slabs.
International Nuclear Information System (INIS)
Raynal, J.
1976-01-01
Closed formulae and recurrence relations for the transformation of a two-body harmonic oscillator wave function to the hyperspherical formalism are given. With them Moshinsky or Smirnov coefficients are obtained from the transformation coefficients of hyperspheric harmonics. For these coefficients the diagonalization method of Talman and Lande reduces to simple recurrence relations which can be used directly to compute them. New closed formulae for these coefficients are also derived: they are needed to compute the two simplest coefficients which determine the sign for the recurrence relation. (Auth.)
Protective Factors, Risk Indicators, and Contraceptive Consistency Among College Women.
Morrison, Leslie F; Sieving, Renee E; Pettingell, Sandra L; Hellerstedt, Wendy L; McMorris, Barbara J; Bearinger, Linda H
2016-01-01
To explore risk and protective factors associated with consistent contraceptive use among emerging adult female college students and whether effects of risk indicators were moderated by protective factors. Secondary analysis of National Longitudinal Study of Adolescent to Adult Health Wave III data. Data collected through in-home interviews in 2001 and 2002. National sample of 18- to 25-year-old women (N = 842) attending 4-year colleges. We examined relationships between protective factors, risk indicators, and consistent contraceptive use. Consistent contraceptive use was defined as use all of the time during intercourse in the past 12 months. Protective factors included external supports of parental closeness and relationship with caring nonparental adult and internal assets of self-esteem, confidence, independence, and life satisfaction. Risk indicators included heavy episodic drinking, marijuana use, and depression symptoms. Multivariable logistic regression models were used to evaluate relationships between protective factors and consistent contraceptive use and between risk indicators and contraceptive use. Self-esteem, confidence, independence, and life satisfaction were significantly associated with more consistent contraceptive use. In a final model including all internal assets, life satisfaction was significantly related to consistent contraceptive use. Marijuana use and depression symptoms were significantly associated with less consistent use. With one exception, protective factors did not moderate relationships between risk indicators and consistent use. Based on our findings, we suggest that risk and protective factors may have largely independent influences on consistent contraceptive use among college women. A focus on risk and protective factors may improve contraceptive use rates and thereby reduce unintended pregnancy among college students. Copyright © 2016 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses. Published
Friction coefficient dependence on electrostatic tribocharging
Burgo, Thiago A. L.; Silva, Cristiane A.; Balestrin, Lia B. S.; Galembeck, Fernando
2013-01-01
Friction between dielectric surfaces produces patterns of fixed, stable electric charges that in turn contribute electrostatic components to surface interactions between the contacting solids. The literature presents a wealth of information on the electronic contributions to friction in metals and semiconductors but the effect of triboelectricity on friction coefficients of dielectrics is as yet poorly defined and understood. In this work, friction coefficients were measured on tribocharged polytetrafluoroethylene (PTFE), using three different techniques. As a result, friction coefficients at the macro- and nanoscales increase many-fold when PTFE surfaces are tribocharged, but this effect is eliminated by silanization of glass spheres rolling on PTFE. In conclusion, tribocharging may supersede all other contributions to macro- and nanoscale friction coefficients in PTFE and probably in other insulating polymers. PMID:23934227
Revised Mark 22 coolant temperature coefficients
International Nuclear Information System (INIS)
Graves, W.E.
1987-01-01
Coolant temperature coefficients for the Mark 22 charge published previously are non-conservative because of the neglect of a significant mechanism which has a positive contribution to reactivity. Even after correcting for this effect, dynamic tests made on a Mark VIB charge in the early 60's suggest the results are still non-conservative. This memorandum takes both of these sources of information into account in making a best estimate of the prompt (coolant plus metal) temperature coefficient. Although no safety issues arise from this work (the overall temperature coefficient still strongly contributes to reactor stability), it is obviously desirable to use best estimates for prompt coefficients in limits and other calculations
Heat transfer coefficient of cryotop during freezing.
Li, W J; Zhou, X L; Wang, H S; Liu, B L; Dai, J J
2013-01-01
Cryotop is an efficient vitrification method for cryopreservation of oocytes. It has been widely used owing to its simple operation and high freezing rate. Recently, the heat transfer performance of cryotop was studied by numerical simulation in several studies. However, the range of heat transfer coefficient in the simulation is uncertain. In this study, the heat transfer coefficient for cryotop during freezing process was analyzed. The cooling rates of 40 percent ethylene glycol (EG) droplet in cryotop during freezing were measured by ultra-fast measurement system and calculated by numerical simulation at different value of heat transfer coefficient. Compared with the results obtained by two methods, the range of the heat transfer coefficient necessary for the numerical simulation of cryotop was determined, which is between 9000 W/(m(2)·K) and 10000 W/(m (2)·K).
Friction coefficient dependence on electrostatic tribocharging.
Burgo, Thiago A L; Silva, Cristiane A; Balestrin, Lia B S; Galembeck, Fernando
2013-01-01
Friction between dielectric surfaces produces patterns of fixed, stable electric charges that in turn contribute electrostatic components to surface interactions between the contacting solids. The literature presents a wealth of information on the electronic contributions to friction in metals and semiconductors but the effect of triboelectricity on friction coefficients of dielectrics is as yet poorly defined and understood. In this work, friction coefficients were measured on tribocharged polytetrafluoroethylene (PTFE), using three different techniques. As a result, friction coefficients at the macro- and nanoscales increase many-fold when PTFE surfaces are tribocharged, but this effect is eliminated by silanization of glass spheres rolling on PTFE. In conclusion, tribocharging may supersede all other contributions to macro- and nanoscale friction coefficients in PTFE and probably in other insulating polymers.
Roughness coefficients for stream channels in Arizona
Aldridge, B.N.; Garrett, J.M.
1973-01-01
When water flows in an open channel, energy is lost through friction along the banks and bed of the channel and through turbulence within the channel. The amount of energy lost is governed by channel roughness, which is expressed in terms of a roughness coefficient. An evaluation of the roughness coefficient is necessary in many hydraulic computations that involve flow in an open channel. Owing to the lack of satisfactory quantitative procedure, the ability of evaluate roughness coefficients can be developed only through experience; however, a basic knowledge of the methods used to assign the coefficients and the factors affecting them will be a great help. One of the most commonly used equations in open-channel hydraulics is that of Manning. The Manning equation is 1.486
Experimental techniques of conversion coefficient measurements
International Nuclear Information System (INIS)
Hamilton, J.H.
1975-01-01
Discusses briefly the history of conversion electron spectra measurements, and the interpretation of the collected data. Then provides a comprehensive review of techniques presently available to measure the conversion coefficients. (Auth.)
Form coefficient of helical toroidal solenoids
International Nuclear Information System (INIS)
Amelin, V.Z.; Kunchenko, V.B.
1982-01-01
For toroidal solenoids with continuous spiral coil, winded according to the laws of equiinclined and simple cylindrical spirals with homogeneous, linearly increasing to the coil periphery and ''Bitter'' distribution of current density, the analytical expressions for the dependence between capacity consumed and generated magnetic field, expressions for coefficients of form similar to Fabry coefficient for cylindrical solenoids are obtained and dependence of the form coefficient and relative volume of solenoid conductor on the number of revolutions of screw line per one circumvention over the large torus radius is also investigated. Analytical expressions of form coefficients and graphical material permit to select the optimum geometry as to capacity consumed both for spiral (including ''force-free'') and conventional toroidal solenoids of magnetic systems in thermonulear installations
Explicit formulas for Clebsch-Gordan coefficients
International Nuclear Information System (INIS)
Rudnicki-Bujnowski, G.
1975-01-01
The problem is to obtain explicit algebraic formulas of Clebsch-Gordan coefficients for high values of angular momentum. The method of solution is an algebraic method based on the Racah formula using the FORMAC programming language. (Auth.)
Diffusion Coefficients of Several Aqueous Alkanolamine Solutions
Snijder, Erwin D.; Riele, Marcel J.M. te; Versteeg, Geert F.; Swaaij, W.P.M. van
1993-01-01
The Taylor dispersion technique was applied for the determination of diffusion coefficients of various systems. Experiments with the system KCl in water showed that the experimental setup provides accurate data. For the alkanolamines monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine
Transport Coefficients from Large Deviation Functions
Directory of Open Access Journals (Sweden)
Chloe Ya Gao
2017-10-01
Full Text Available We describe a method for computing transport coefficients from the direct evaluation of large deviation functions. This method is general, relying on only equilibrium fluctuations, and is statistically efficient, employing trajectory based importance sampling. Equilibrium fluctuations of molecular currents are characterized by their large deviation functions, which are scaled cumulant generating functions analogous to the free energies. A diffusion Monte Carlo algorithm is used to evaluate the large deviation functions, from which arbitrary transport coefficients are derivable. We find significant statistical improvement over traditional Green–Kubo based calculations. The systematic and statistical errors of this method are analyzed in the context of specific transport coefficient calculations, including the shear viscosity, interfacial friction coefficient, and thermal conductivity.
Transport Coefficients from Large Deviation Functions
Gao, Chloe; Limmer, David
2017-10-01
We describe a method for computing transport coefficients from the direct evaluation of large deviation function. This method is general, relying on only equilibrium fluctuations, and is statistically efficient, employing trajectory based importance sampling. Equilibrium fluctuations of molecular currents are characterized by their large deviation functions, which is a scaled cumulant generating function analogous to the free energy. A diffusion Monte Carlo algorithm is used to evaluate the large deviation functions, from which arbitrary transport coefficients are derivable. We find significant statistical improvement over traditional Green-Kubo based calculations. The systematic and statistical errors of this method are analyzed in the context of specific transport coefficient calculations, including the shear viscosity, interfacial friction coefficient, and thermal conductivity.
A new approach to estimate Angstrom coefficients
International Nuclear Information System (INIS)
Abdel Wahab, M.
1991-09-01
A simple quadratic equation to estimate global solar radiation with coefficients depending on some physical atmospheric parameters is presented. The importance of the second order and sensitivity to some climatic variations is discussed. (author). 8 refs, 4 figs, 2 tabs
A new proposal for Lagrangian correlation coefficient
International Nuclear Information System (INIS)
Altinsoy, N.; Tugrul, A.B.
2002-01-01
The statistical description of dispersion in turbulent flow was first considered by Taylor (Proc. London Math. Soc. 20 (1921) 196) and the statistical properties of the field were determined by Lagrangian correlation coefficient R L (τ). Frenkiel (Adv. Appl. Mech. 3 (1953) 61) has proposed several simple forms for R L (τ). Some workers have investigated for a proper form of the Lagrangian correlation coefficient. In this work, a new proposal for the Lagrangian correlation coefficient is proposed and discussed. It can be written in general form with the one of the Frenkiel's (Adv. Appl. Mech. 3 (1953) 61) Lagrangian correlation coefficient. There is very satisfactory agreement between the new correlation and the experiment
Modeling Ballasted Tracks for Runoff Coefficient C
2012-08-01
In this study, the Regional Transportation District (RTD)s light rail tracks were modeled to determine the Rational Method : runoff coefficient, C, values corresponding to ballasted tracks. To accomplish this, a laboratory study utilizing a : rain...
Relativistic neoclassical transport coefficients with momentum correction
International Nuclear Information System (INIS)
Marushchenko, I.; Azarenkov, N.A.
2016-01-01
The parallel momentum correction technique is generalized for relativistic approach. It is required for proper calculation of the parallel neoclassical flows and, in particular, for the bootstrap current at fusion temperatures. It is shown that the obtained system of linear algebraic equations for parallel fluxes can be solved directly without calculation of the distribution function if the relativistic mono-energetic transport coefficients are already known. The first relativistic correction terms for Braginskii matrix coefficients are calculated.
Torsion method for measuring piezooptic coefficients
Energy Technology Data Exchange (ETDEWEB)
Skab, I.; Smaga, I.; Savaryn, V.; Vasylkiv, Yu.; Vlokh, R. [Institute of Physical Optics, Lviv (Ukraine)
2011-01-15
We develop and describe analytically a torsion method for measuring piezooptic coefficients associated with shear stresses. It is shown that the method enables to increase significantly the accuracy of determination of piezooptic coefficients. The method and the appropriate apparatus are verified experimentally on the example of LiNbO{sub 3} crystals. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)
Measuring Resource Inequality: The Gini Coefficient
Directory of Open Access Journals (Sweden)
Michael T. Catalano
2009-07-01
Full Text Available This paper stems from work done by the authors at the Mathematics for Social Justice Workshop held in June of 2007 at Middlebury College. We provide a description of the Gini coefficient and some discussion of how it can be used to promote quantitative literacy skills in mathematics courses. The Gini Coefficient was introduced in 1921 by Italian statistician Corrado Gini as a measure of inequality. It is defined as twice the area between two curves. One, the Lorenz curve for a given population with respect to a given resource, represents the cumulative percentage of the resource as a function of the cumulative percentage of the population that shares that percentage of the resource. The second curve is the line y = x which is the Lorenz curve for a population which shares the resource equally. The Gini coefficient can be interpreted as the percentage of inequality represented in the population with respect to the given resource. We propose that the Gini coefficient can be used to enhance students’ understanding of calculus concepts and provide practice for students in using both calculus and quantitative literacy skills. Our examples are based mainly on distribution of energy resources using publicly available data from the Energy Information Agency of the United States Government. For energy resources within the United States, we find that by household, the Gini coefficient is 0.346, while using the 51 data points represented by the states and Washington D.C., the Gini coefficient is 0.158. When we consider the countries of the world as a population of 210, the Gini coefficient is 0.670. We close with ideas for questions which can be posed to students and discussion of the experiences two other mathematics instructors have had incorporating the Gini coefficient into pre-calculus-level mathematics classes.
The Binomial Coefficient for Negative Arguments
Kronenburg, M. J.
2011-01-01
The definition of the binomial coefficient in terms of gamma functions also allows non-integer arguments. For nonnegative integer arguments the gamma functions reduce to factorials, leading to the well-known Pascal triangle. Using a symmetry formula for the gamma function, this definition is extended to negative integer arguments, making the symmetry identity for binomial coefficients valid for all integer arguments. The agreement of this definition with some other identities and with the bin...
Investigation of photon attenuation coefficients for marble
International Nuclear Information System (INIS)
Basyigit, C; Akkurt, I; Kilincarslan, S; Akkurt, A
2005-01-01
The total linear attenuation coefficients μ (cm -1 ) have been obtained using the XCOM program at photon energies of 1 keV to 1 GeV for six different natural marbles produced in different places in Turkey. The individual contribution of photon interaction processes to the total linear attenuation coefficients for marble has been investigated. The calculated results were also compared with the measurements. The results obtained for marble were also compared with concrete. (note)
Analysis of flow coefficient in chair manufacture
Ivković Dragoljub; Živković Slaven
2005-01-01
The delivery on time is not possible without the good-quality planning of deadlines, i.e. planning of the manufacturing process duration. The study of flow coefficient enables the realistic forecasting of the manufacturing process duration. This paper points to the significance of the study of flow coefficient on scientific basis so as to determine the terms of the end of the manufacture of chairs made of sawn timber. Chairs are the products of complex construction, often almost completely ma...
On computing Laplace's coefficients and their derivatives.
Gerasimov, I. A.; Vinnikov, E. L.
The algorithm of computing Laplace's coefficients and their derivatives is proposed with application of recurrent relations. The A.G.M.-method is used for the calculation of values L0(0), L0(1). The FORTRAN-program corresponding to the algorithm is given. The precision control was provided with numerical integrating by Simpsons method. The behavior of Laplace's coefficients and their third derivatives whith varying indices K, n for fixed values of the α-parameter is presented graphically.
Drag Coefficient Estimation in Orbit Determination
McLaughlin, Craig A.; Manee, Steve; Lichtenberg, Travis
2011-07-01
Drag modeling is the greatest uncertainty in the dynamics of low Earth satellite orbits where ballistic coefficient and density errors dominate drag errors. This paper examines fitted drag coefficients found as part of a precision orbit determination process for Stella, Starlette, and the GEOSAT Follow-On satellites from 2000 to 2005. The drag coefficients for the spherical Stella and Starlette satellites are assumed to be highly correlated with density model error. The results using MSIS-86, NRLMSISE-00, and NRLMSISE-00 with dynamic calibration of the atmosphere (DCA) density corrections are compared. The DCA corrections were formulated for altitudes of 200-600 km and are found to be inappropriate when applied at 800 km. The yearly mean fitted drag coefficients are calculated for each satellite for each year studied. The yearly mean drag coefficients are higher for Starlette than Stella, where Starlette is at a higher altitude. The yearly mean fitted drag coefficients for all three satellites decrease as solar activity decreases after solar maximum.
Monitoring device for local power peaking coefficients
International Nuclear Information System (INIS)
Mihashi, Ishi
1987-01-01
Purpose: To determine and monitor the local power peaking coefficients by a method not depending on the combination of fuel types. Constitution: Representative values for the local power distribution can be obtained by determining corresponding burn-up degrees based on the burn-up degree of each of fuel assembly segments obtained in a power distribution monitor and by the interpolation and extrapolation of void coefficients. The typical values are multiplied with compensation coefficients for the control rod effect and coefficients for compensating the effect of adjacent fuel assemblies in a calculation device to obtain typical values for the present local power distribution compensated with all of the effects. Further, the calculation device compares them with typical values of the present local power distribution to obtain an aimed local power peaking coefficient as the maximum value thereof. According to the present invention, since the local power peaking coefficients can be determined not depending on the combination of the kind of fuels, if the combination of fuel assemblies is increased upon fuel change, the amount of operation therefor is not increased. (Kamimura, M.)
Monitoring device for local power peaking coefficient
International Nuclear Information System (INIS)
Mitsuhashi, Ishi
1987-01-01
Purpose: To monitor the local power peaking coefficients obtained by the method not depending on the combination of fuel types. Method: A plurality of representative values for the local power distribution determined by the nuclear constant calculation for one fuel assembly are memorized regarding each of the burn-up degree and the void coefficient on every positions and fuel types in fuel rod assemblies. While on the other hand, the representative values for the local power distribution as described above are compensated by a compensation coefficient considering the effect of adjacent segments and a control rod compensation coefficient considering the effect due to the control rod insertion relative to the just-mentioned compensation coefficient. Then, the maximum value among them is selected to determine the local power peaking coefficient at each of the times and each of the segments, which is monitored. According to this system, the calculation and the working required for the fitting work depending on the combination of fuel types are no more required at all to facilitate the maintenance as well. (Horiuchi, T.)
The Internalized Stigma of Mental Illness (ISMI) scale: validation of the Japanese version.
Tanabe, Yosuke; Hayashi, Kunihiko; Ideno, Yuki
2016-04-29
The present study investigated the reliability and validity of a Japanese version of the Internalized Stigma of Mental Illness (ISMI) scale, designed to assess internalized stigma experienced by people with mental illness. A survey was conducted with 173 outpatients with mental illness who attended psychiatric clinics on a regular basis. A retest was conducted with 51 participants to evaluate the scale's psychometric properties. The alpha coefficient for the overall internal consistency was 0.91, and the coefficients of the individual ISMI subscales ranged from 0.57 to 0.81. The test-retest reliability was r = 0.85 (n = 51, P stigma resistance items excluded. The Japanese version of the ISMI scale demonstrated similar reliability and validity to the original English version. Therefore, the Japanese version of the ISMI scale may be an effective and valid tool to measure internalized stigma among Japanese people who have a mental illness.
Correlation of heat transfer coefficient in quenching process using ABAQUS
Davare, Sandeep Kedarnath; Balachandran, G.; Singh, R. K. P.
2018-04-01
During the heat treatment by quenching in a liquid medium the convective heat transfer coefficient plays a crucial role in the extraction of heat. The heat extraction ultimately influences the cooling rate and hence the hardness and mechanical properties. A Finite Element analysis of quenching a simple flat copper sample with different orientation of sample and with different quenchant temperatures were carried out to check and verify the results obtained from the experiments. The heat transfer coefficient (HTC) was calculated from temperature history in a simple flat copper disc sample experimentally. This HTC data was further used as input to simulation software and the cooling curves were back calculated. The results obtained from software and using experimentation shows nearly consistent values.
Non-Markovian dynamics of quantum systems: formalism, transport coefficients
International Nuclear Information System (INIS)
Kanokov, Z.; Palchikov, Yu.V.; Antonenko, N.V.; Adamian, G.G.; Kanokov, Z.; Adamian, G.G.; Scheid, W.
2004-01-01
Full text: The generalized Linbland equations with non-stationary transport coefficients are derived from the Langevin equations for the case of nonlinear non-Markovian noise [1]. The equations of motion for the collective coordinates are consistent with the generalized quantum fluctuation dissipation relations. The microscopic justification of the Linbland axiomatic approach is performed. Explicit expressions for the time-dependent transport coefficients are presented for the case of FC- and RWA-oscillators and a general linear coupling in coordinate and in momentum between the collective subsystem and heat bath. The explicit equations for the correlation functions show that the Onsanger's regression hypothesis does not hold exactly for the non-Markovian equations of motion. However, under some conditions the regression of fluctuations goes to zero in the same manner as the average values. In the low and high temperature regimes we found that the dissipation leads to long-time tails in correlation functions in the RWA-oscillator. In the case of the FC-oscillator a non-exponential power-like decay of the correlation function in coordinate is only obtained only at the low temperature limit. The calculated results depend rather weakly on the memory time in many applications. The found transient times for diffusion coefficients D pp (t), D qp (t) and D qq (t) are quite short. The value of classical diffusion coefficients in momentum underestimates the asymptotic value of quantum one D pp (t), but the asymptotic values of classical σ qq c and quantum σ qq second moments are close due to the negativity of quantum mixed diffusion coefficient D qp (t)
THE DETERMINATION OF DIFFUSION COEFFICIENT OF INVERT MATERIALS
International Nuclear Information System (INIS)
P. Heller and J. Wright
2000-01-01
The Engineered Barrier System (EBS) Testing Department is performing tests in the Department of Energy's Atlas Facility to evaluate the performance of various means for increasing the time for breakthrough of radionuclides from the waste package to the base of the invert. This includes testing various barriers in the invert as a means of increasing breakthrough time through the process of diffusion. A diffusion barrier may serve as an invert material for the emplacement drifts. The invert material may consist of crushed tuff from the repository excavation at Yucca Mountain or silica sand. The objective of this report is to determine the diffusion coefficient of the crushed tuff and silica sand invert materials specified by the EBS Testing Department. The laboratory derived information from the testing was used in the Nernst-Einstein equation (Jurinak et al. 1987, p. 626) to determine the diffusion coefficient of the invert material. This report transmits the results and describes the methodology and interpretation. The scope of this report is to determine the diffusion coefficients of the invert materials mentioned above using the centrifuge at UFA Ventures. Standard laboratory procedures, described in Section 2 of this report, were used. The diffusion coefficients are to be determined over a range of moisture contents. The report contains the diffusion coefficients calculated by the Nernst-Einstein equation (Jurinak et al. 1987, p. 626) that become a part of the Technical Database. Raw data is also included in the report, however this data does not become part of the Technical Database as per Section 3.23 of AP-SIII.3Q ''Submittal and Incorporation of Data to the Technical Data Management System''. A sieve analysis of the samples was not conducted as part of this report, but sieve analysis may be accomplished as part of other reports. Two samples of crushed tuff and two samples of silica sand were tested
A Study on the Consistency of Discretization Equation in Unsteady Heat Transfer Calculations
Directory of Open Access Journals (Sweden)
Wenhua Zhang
2013-01-01
Full Text Available The previous studies on the consistency of discretization equation mainly focused on the finite difference method, but the issue of consistency still remains with several problems far from totally solved in the actual numerical computation. For instance, the consistency problem is involved in the numerical case where the boundary variables are solved explicitly while the variables away from the boundary are solved implicitly. And when the coefficient of discretization equation of nonlinear numerical case is the function of variables, calculating the coefficient explicitly and the variables implicitly might also give rise to consistency problem. Thus the present paper mainly researches the consistency problems involved in the explicit treatment of the second and third boundary conditions and that of thermal conductivity which is the function of temperature. The numerical results indicate that the consistency problem should be paid more attention and not be neglected in the practical computation.
The empirical Gaia G-band extinction coefficient
Danielski, C.; Babusiaux, C.; Ruiz-Dern, L.; Sartoretti, P.; Arenou, F.
2018-06-01
Context. The first Gaia data release unlocked the access to photometric information for 1.1 billion sources in the G-band. Yet, given the high level of degeneracy between extinction and spectral energy distribution for large passbands such as the Gaia G-band, a correction for the interstellar reddening is needed in order to exploit Gaia data. Aims: The purpose of this manuscript is to provide the empirical estimation of the Gaia G-band extinction coefficient kG for both the red giants and main sequence stars in order to be able to exploit the first data release DR1. Methods: We selected two samples of single stars: one for the red giants and one for the main sequence. Both samples are the result of a cross-match between Gaia DR1 and 2MASS catalogues; they consist of high-quality photometry in the G-, J- and KS-bands. These samples were complemented by temperature and metallicity information retrieved from APOGEE DR13 and LAMOST DR2 surveys, respectively. We implemented a Markov chain Monte Carlo method where we used (G - KS)0 versus Teff and (J - KS)0 versus (G - KS)0, calibration relations to estimate the extinction coefficient kG and we quantify its corresponding confidence interval via bootstrap resampling. We tested our method on samples of red giants and main sequence stars, finding consistent solutions. Results: We present here the determination of the Gaia extinction coefficient through a completely empirical method. Furthermore we provide the scientific community with a formula for measuring the extinction coefficient as a function of stellar effective temperature, the intrinsic colour (G - KS)0, and absorption.
González-Ortiz, Ailema Janeth; Arce-Santander, Celene Viridiana; Vega-Vega, Olynka; Correa-Rotter, Ricardo; Espinosa-Cuevas, María de Los Angeles
2014-10-04
The protein-energy wasting syndrome (PEW) is a condition of malnutrition, inflammation, anorexia and wasting of body reserves resulting from inflammatory and non-inflammatory conditions in patients with chronic kidney disease (CKD).One way of assessing PEW, extensively described in the literature, is using the Malnutrition Inflammation Score (MIS). To assess the reliability and consistency of MIS for diagnosis of PEW in Mexican adults with CKD on hemodialysis (HD). Study of diagnostic tests. A sample of 45 adults with CKD on HD were analyzed during the period June-July 2014.The instrument was applied on 2 occasions; the test-retest reliability was calculated using the Intraclass Correlation Coefficient (ICC); the internal consistency of the questionnaire was analyzed using Cronbach's αcoefficient. A weighted Kappa test was used to estimate the validity of the instrument; the result was subsequently compared with the Bilbrey nutritional index (BNI). The reliability of the questionnaires, evaluated in the patient sample, was ICC=0.829.The agreement between MIS observations was considered adequate, k= 0.585 (p <0.001); when comparing it with BNI, a value of k = 0.114 was obtained (p <0.001).In order to estimate the tendency, a correlation test was performed. The r² correlation coefficient was 0.488 (P <0.001). MIS has adequate reliability and validity for diagnosing PEW in the population with chronic kidney disease on HD. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
A new approach to hull consistency
Directory of Open Access Journals (Sweden)
Kolev Lubomir
2016-06-01
Full Text Available Hull consistency is a known technique to improve the efficiency of iterative interval methods for solving nonlinear systems describing steady-states in various circuits. Presently, hull consistency is checked in a scalar manner, i.e. successively for each equation of the nonlinear system with respect to a single variable. In the present poster, a new more general approach to implementing hull consistency is suggested which consists in treating simultaneously several equations with respect to the same number of variables.
Replica consistency in a Data Grid
International Nuclear Information System (INIS)
Domenici, Andrea; Donno, Flavia; Pucciani, Gianni; Stockinger, Heinz; Stockinger, Kurt
2004-01-01
A Data Grid is a wide area computing infrastructure that employs Grid technologies to provide storage capacity and processing power to applications that handle very large quantities of data. Data Grids rely on data replication to achieve better performance and reliability by storing copies of data sets on different Grid nodes. When a data set can be modified by applications, the problem of maintaining consistency among existing copies arises. The consistency problem also concerns metadata, i.e., additional information about application data sets such as indices, directories, or catalogues. This kind of metadata is used both by the applications and by the Grid middleware to manage the data. For instance, the Replica Management Service (the Grid middleware component that controls data replication) uses catalogues to find the replicas of each data set. Such catalogues can also be replicated and their consistency is crucial to the correct operation of the Grid. Therefore, metadata consistency generally poses stricter requirements than data consistency. In this paper we report on the development of a Replica Consistency Service based on the middleware mainly developed by the European Data Grid Project. The paper summarises the main issues in the replica consistency problem, and lays out a high-level architectural design for a Replica Consistency Service. Finally, results from simulations of different consistency models are presented
Discharge Coefficient of Rectangular Short-Crested Weir with Varying Slope Coefficients
Directory of Open Access Journals (Sweden)
Yuejun Chen
2018-02-01
Full Text Available Rectangular short-crested weirs are widely used for simple structure and high discharge capacity. As one of the most important and influential factors of discharge capacity, side slope can improve the hydraulic characteristics of weirs at special conditions. In order to systemically study the effects of upstream and downstream slope coefficients S1 and S2 on overflow discharge coefficient in a rectangular short-crested weir the Volume of Fluid (VOF method and the Renormalization Group (RNG κ-ε turbulence model are used. In this study, the slope coefficient ranges from V to 3H:1V and each model corresponds to five total energy heads of H0 ranging from 8.0 to 24.0 cm. Comparisons of discharge coefficients and free surface profiles between simulated and laboratory results display a good agreement. The simulated results show that the difference of discharge coefficients will decrease with upstream slopes and increase with downstream slopes as H0 increases. For a given H0, the discharge coefficient has a convex parabolic relation with S1 and a piecewise linearity relation with S2. The maximum discharge coefficient is always obtained at S2 = 0.8. There exists a difference between upstream and downstream slope coefficients in the influence range of free surface curvatures. Furthermore, a proposed discharge coefficient equation by nonlinear regression is a function of upstream and downstream slope coefficients.
An energetically consistent vertical mixing parameterization in CCSM4
DEFF Research Database (Denmark)
Nielsen, Søren Borg; Jochum, Markus; Eden, Carsten
2018-01-01
An energetically consistent stratification-dependent vertical mixing parameterization is implemented in the Community Climate System Model 4 and forced with energy conversion from the barotropic tides to internal waves. The structures of the resulting dissipation and diffusivity fields are compared......, however, depends greatly on the details of the vertical mixing parameterizations, where the new energetically consistent parameterization results in low thermocline diffusivities and a sharper and shallower thermocline. It is also investigated if the ocean state is more sensitive to a change in forcing...
Experimental research on friction coefficient between grain bulk and bamboo clappers
Tang, Gan; Sun, Ping; Zhao, Yanqi; Yin, Lingfeng; Zhuang, Hong
2017-12-01
A silo is an important piece of storage equipment, especially in the grain industry. The internal friction angle and the friction coefficient between the grain and the silo wall are the main parameters needed for calculating the lateral pressure of the silo wall. Bamboo is used in silo walls, but there are no provisions about the friction coefficient between bulk grain and bamboo clappers in existing codes. In this paper, the material of the silo wall is bamboo. The internal friction of five types of grain and the friction coefficient between the grain and the bamboo clappers were measured with an equal-strain direct shear apparatus. By comparing the experimental result values with the code values, the friction coefficient between the grain bulk and bamboo clappers is lower than that between grain and steel wall and that between grain and concrete wall. The differences in value are 0.21 and 0.09, respectively.
Transfer coefficients of radionuclides from feed to livestock products
International Nuclear Information System (INIS)
1995-03-01
The accumulation of data on radionuclide transfer are poor in Japan and those are limited to 90 Sr, 137 Cs and 131 I released from the previous atomic bomb experiments. However, in Europe, intensive studies on environment RI level which affects the restriction of the intake for meats and milk products have been made as the measures against the environment radioactivity due to Chernobyl accident. The transfer coefficients of radionuclides to meats and milk products were estimated on a basis of the data published in the Science of the Total Environment vol.85(1989), Oxford University and CEC Radiation Protection, EUR 12608 EN, Luxembourg, 1990 in addition to the data on Exclusion of Radioactivity from foods, Environment Parameter, series No. 4. On the other hand, the transfer coefficients for Japanese were estimated using the concerned data from published reports and the environment radioactivity data reported by national and local government bodies. In this book, many new data of transfer coefficient are presented in tables along with the previous data collected by international nuclear energy agencies and respective national facilities concerned. (M.N.)
Lattice cell diffusion coefficients. Definitions and comparisons
International Nuclear Information System (INIS)
Hughes, R.P.
1980-01-01
Definitions of equivalent diffusion coefficients for regular lattices of heterogeneous cells have been given by several authors. The paper begins by reviewing these different definitions and the unification of their derivation. This unification makes clear how accurately each definition (together with appropriate cross-section definitions to preserve the eigenvalue) represents the individual reaction rates within the cell. The approach can be extended to include asymmetric cells and whereas before, the buckling describing the macroscopic flux shape was real, here it is found to be complex. A neutron ''drift'' coefficient as well as a diffusion coefficient is necessary to produce the macroscopic flux shape. The numerical calculation of the various different diffusion coefficients requires the solutions of equations similar to the ordinary transport equation for an infinite lattice. Traditional reactor physics codes are not sufficiently flexible to solve these equations in general. However, calculations in certain simple cases are presented and the theoretical results quantified. In difficult geometries, Monte Carlo techniques can be used to calculate an effective diffusion coefficient. These methods relate to those already described provided that correlation effects between different generations of neutrons are included. Again, these effects are quantified in certain simple cases. (author)
Experimental methodology for obtaining sound absorption coefficients
Directory of Open Access Journals (Sweden)
Carlos A. Macía M
2011-07-01
Full Text Available Objective: the authors propose a new methodology for estimating sound absorption coefficients using genetic algorithms. Methodology: sound waves are generated and conducted along a rectangular silencer. The waves are then attenuated by the absorbing material covering the silencer’s walls. The attenuated sound pressure level is used in a genetic algorithm-based search to find the parameters of the proposed attenuation expressions that include geometric factors, the wavelength and the absorption coefficient. Results: a variety of adjusted mathematical models were found that make it possible to estimate the absorption coefficients based on the characteristics of a rectangular silencer used for measuring the attenuation of the noise that passes through it. Conclusions: this methodology makes it possible to obtain the absorption coefficients of new materials in a cheap and simple manner. Although these coefficients might be slightly different from those obtained through other methodologies, they provide solutions within the engineering accuracy ranges that are used for designing noise control systems.
Radon emanation coefficients in sandy soils
International Nuclear Information System (INIS)
Holy, K.; Polaskova, A.; Baranova, A.; Sykora, I.; Hola, O.
1998-01-01
In this contribution the results of the study of an influence of the water content on the emanation coefficient for two sandy soil samples are reported. These samples were chosen on the because of the long-term continual monitoring of the 222 Rn concentration just in such types of soils and this radon concentration showed the significant variations during a year. These variations are chiefly given in connection with the soil moisture. Therefore, the determination of the dependence of the emanation coefficient of radon on the water content can help to evaluate the influence of the soil moisture variations of radon concentrations in the soil air. The presented results show that the emanation coefficient reaches the constant value in the wide interval of the water content for both sandy soil samples. Therefore, in the common range of the soil moisture (5 - 20 %) it is impossible to expect the variations of the radon concentration in the soil air due to the change of the emanation coefficient. The expressive changes of the radon concentration in the soil air can be observed in case of the significant decrease of the emanation coefficient during the soil drying when the water content decreases under 5 % or during the complete filling of the soil pores by the water. (authors)
Student Effort, Consistency, and Online Performance
Patron, Hilde; Lopez, Salvador
2011-01-01
This paper examines how student effort, consistency, motivation, and marginal learning, influence student grades in an online course. We use data from eleven Microeconomics courses taught online for a total of 212 students. Our findings show that consistency, or less time variation, is a statistically significant explanatory variable, whereas…
Translationally invariant self-consistent field theories
International Nuclear Information System (INIS)
Shakin, C.M.; Weiss, M.S.
1977-01-01
We present a self-consistent field theory which is translationally invariant. The equations obtained go over to the usual Hartree-Fock equations in the limit of large particle number. In addition to deriving the dynamic equations for the self-consistent amplitudes we discuss the calculation of form factors and various other observables
Sticky continuous processes have consistent price systems
DEFF Research Database (Denmark)
Bender, Christian; Pakkanen, Mikko; Sayit, Hasanjan
Under proportional transaction costs, a price process is said to have a consistent price system, if there is a semimartingale with an equivalent martingale measure that evolves within the bid-ask spread. We show that a continuous, multi-asset price process has a consistent price system, under...
Consistent-handed individuals are more authoritarian.
Lyle, Keith B; Grillo, Michael C
2014-01-01
Individuals differ in the consistency with which they use one hand over the other to perform everyday activities. Some individuals are very consistent, habitually using a single hand to perform most tasks. Others are relatively inconsistent, and hence make greater use of both hands. More- versus less-consistent individuals have been shown to differ in numerous aspects of personality and cognition. In several respects consistent-handed individuals resemble authoritarian individuals. For example, both consistent-handedness and authoritarianism have been linked to cognitive inflexibility. Therefore we hypothesised that consistent-handedness is an external marker for authoritarianism. Confirming our hypothesis, we found that consistent-handers scored higher than inconsistent-handers on a measure of submission to authority, were more likely to identify with a conservative political party (Republican), and expressed less-positive attitudes towards out-groups. We propose that authoritarianism may be influenced by the degree of interaction between the left and right brain hemispheres, which has been found to differ between consistent- and inconsistent-handed individuals.
Testing the visual consistency of web sites
van der Geest, Thea; Loorbach, N.R.
2005-01-01
Consistency in the visual appearance of Web pages is often checked by experts, such as designers or reviewers. This article reports a card sort study conducted to determine whether users rather than experts could distinguish visual (in-)consistency in Web elements and pages. The users proved to
Consistent spectroscopy for a extended gauge model
International Nuclear Information System (INIS)
Oliveira Neto, G. de.
1990-11-01
The consistent spectroscopy was obtained with a Lagrangian constructed with vector fields with a U(1) group extended symmetry. As consistent spectroscopy is understood the determination of quantum physical properties described by the model in an manner independent from the possible parametrizations adopted in their description. (L.C.J.A.)
Modeling and Testing Legacy Data Consistency Requirements
DEFF Research Database (Denmark)
Nytun, J. P.; Jensen, Christian Søndergaard
2003-01-01
An increasing number of data sources are available on the Internet, many of which offer semantically overlapping data, but based on different schemas, or models. While it is often of interest to integrate such data sources, the lack of consistency among them makes this integration difficult....... This paper addresses the need for new techniques that enable the modeling and consistency checking for legacy data sources. Specifically, the paper contributes to the development of a framework that enables consistency testing of data coming from different types of data sources. The vehicle is UML and its...... accompanying XMI. The paper presents techniques for modeling consistency requirements using OCL and other UML modeling elements: it studies how models that describe the required consistencies among instances of legacy models can be designed in standard UML tools that support XMI. The paper also considers...
Computation of Clebsch-Gordan and Gaunt coefficients using binomial coefficients
International Nuclear Information System (INIS)
Guseinov, I.I.; Oezmen, A.; Atav, Ue
1995-01-01
Using binomial coefficients the Clebsch-Gordan and Gaunt coefficients were calculated for extremely large quantum numbers. The main advantage of this approach is directly calculating these coefficients, instead of using recursion relations. Accuracy of the results is quite high for quantum numbers l 1 , and l 2 up to 100. Despite direct calculation, the CPU times are found comparable with those given in the related literature. 11 refs., 1 fig., 2 tabs
The internal dosimetry code PLEIADES.
Fell, T P; Phipps, A W; Smith, T J
2007-01-01
The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts-the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included.
The internal dosimetry code PLEIADES
International Nuclear Information System (INIS)
Fell, T. P.; Phipps, A. W.; Smith, T. J.
2007-01-01
The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts - the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included. (authors)
Curvature of Indoor Sensor Network: Clustering Coefficient
Directory of Open Access Journals (Sweden)
2009-03-01
Full Text Available We investigate the geometric properties of the communication graph in realistic low-power wireless networks. In particular, we explore the concept of the curvature of a wireless network via the clustering coefficient. Clustering coefficient analysis is a computationally simplified, semilocal approach, which nevertheless captures such a large-scale feature as congestion in the underlying network. The clustering coefficient concept is applied to three cases of indoor sensor networks, under varying thresholds on the link packet reception rate (PRR. A transition from positive curvature (“meshed” network to negative curvature (“core concentric” network is observed by increasing the threshold. Even though this paper deals with network curvature per se, we nevertheless expand on the underlying congestion motivation, propose several new concepts (network inertia and centroid, and finally we argue that greedy routing on a virtual positively curved network achieves load balancing on the physical network.
Estimating Runoff Coefficients Using Weather Radars
DEFF Research Database (Denmark)
Ahm, Malte; Thorndahl, Søren Liedtke; Rasmussen, Michael R.
2012-01-01
This paper presents a method for estimating runoff coefficients of urban drainage catchments based on a combination of high resolution weather radar data and insewer flow measurements. By utilising the spatial variability of the precipitation it is possible to estimate the runoff coefficients...... of separate subcatchments. The method is demonstrated through a case study of an urban drainage catchment (678ha) located in the municipality of Aarhus, Denmark. The study has proven it is possible to use corresponding measurements of the relative rainfall distribution over the catchment and runoff...... measurements to identify the runoff coefficients at subcatchment level. The number of potential subcatchments is limited by the number of available rainfall events with a sufficient spatial variability....
Experimental determination of fission gas adsorption coefficients
International Nuclear Information System (INIS)
Lovell, R.; Underhill, D.W.
1979-01-01
Large charcoal beds have been used for a number of years for the holdup and decay of radioactive isotopes of krypton and xenon. Reliable design of these beds depends on an accurate knowledge of the adsorption coefficient of krypton and xenon on the adsorbents used in these beds. It is somewhat surprising that there is no standard procedure of determining the adsorption coefficient for krypton and xenon. Fundamental information needed to establish a standardized reproducible test procedure is given emphasizing the breakthrough curves commonly used to analyze dynamic adsorption data can lead to serious systematic errors and the fact that the adsorption coefficient, if calculated from the arithmetic holding time, is independent of geometric factors such as the shape of the adsorption bed and the irregular shape of the adsorbent
Ideal related K-theory with coefficients
DEFF Research Database (Denmark)
Eilers, Soren; Restorff, Gunnar; Ruiz, Efren
2017-01-01
In this paper, we define an invariant, which we believe should be the substitute for total K-theory in the case when there is one distinguished ideal. Moreover, some diagrams relating the new groups to the ordinary K-groups with coefficients are constructed. These diagrams will in most cases help...... to determine the new groups, and will in a companion paper be used to prove a universal multi-coefficient theorem for the one distinguished ideal case for a large class of algebras......In this paper, we define an invariant, which we believe should be the substitute for total K-theory in the case when there is one distinguished ideal. Moreover, some diagrams relating the new groups to the ordinary K-groups with coefficients are constructed. These diagrams will in most cases help...
Nozzle geometry variations on the discharge coefficient
Directory of Open Access Journals (Sweden)
M.M.A. Alam
2016-03-01
Full Text Available Numerical works have been conducted to investigate the effect of nozzle geometries on the discharge coefficient. Several contoured converging nozzles with finite radius of curvatures, conically converging nozzles and conical divergent orifices have been employed in this investigation. Each nozzle and orifice has a nominal exit diameter of 12.7×10−3 m. A 3rd order MUSCL finite volume method of ANSYS Fluent 13.0 was used to solve the Reynolds-averaged Navier–Stokes equations in simulating turbulent flows through various nozzle inlet geometries. The numerical model was validated through comparison between the numerical results and experimental data. The results obtained show that the nozzle geometry has pronounced effect on the sonic lines and discharge coefficients. The coefficient of discharge was found differ from unity due to the non-uniformity of flow parameters at the nozzle exit and the presence of boundary layer as well.
Characteristics of equilibrium and perturbed transport coefficients in tokamaks
International Nuclear Information System (INIS)
Gentle, K.W.
1995-01-01
Although the evolution of a perturbation to a tokamak equilibrium can generally be described by local transport coefficients modestly enhanced above the equilibrium values, there are some significant cases for which this is inadequate. The density profile evolution in ASDEX-U occurs far more rapidly than is consistent with reasonable particle confinement times, and the evolution of cold pulses in TEXT requires nonlocal behavior in the core and some kind of anomaly near the periphery. The experiments are suggesting effects beyond standard local turbulent transport models. (orig.)
Measurements of the gaseous multiplication coefficient in pure isobutane
Energy Technology Data Exchange (ETDEWEB)
Lima, Iara B.; Vivaldini, Tulio C.; Goncalves, Josemary A.C.; Botelho, Suzana; Tobias, Carmen C.B., E-mail: ccbueno@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Ridenti, Marco A.; Pascholati, Paulo R. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Fisica. Lab. do Acelerador Linear; Fonte, Paulo; Mangiarotti, Alessio [Universidade de Coimbra (Portugal). Dept de Fisica. Lab. de Instrumentacao e Fisica Experimental de Particulas
2009-07-01
In this work we present the preliminary studies of the first Townsend coefficient behavior in isobutane for reduced electric fields ranging from 173 Td up to 281 Td by means of signal amplitude analysis. The measurements were based on the Pulsed Townsend technique. The experimental setup consists of two parallel plates housed in a stainless steel chamber at gas flow regime. In our configuration, the primary electrons are produced by irradiating the cathode with a fast nitrogen laser (700 ps pulse duration). In order to validate the technique and to analyze effects of non-uniformity, results for nitrogen are also presented. (author)
Connection between Fourier coefficient and Discretized Cartesian path integration
International Nuclear Information System (INIS)
Coalson, R.D.
1986-01-01
The relationship between so-called Discretized and Fourier coefficient formulations of Cartesian path integration is examined. In particular, an intimate connection between the two is established by rewriting the Discretized formulation in a manifestly Fourier-like way. This leads to improved understanding of both the limit behavior and the convergence properties of computational prescriptions based on the two formalisms. The performance of various prescriptions is compared with regard to calculation of on-diagonal statistical density matrix elements for a number of prototypical 1-d potentials. A consistent convergence order among these prescriptions is established
Measurements of the gaseous multiplication coefficient in pure isobutane
International Nuclear Information System (INIS)
Lima, Iara B.; Vivaldini, Tulio C.; Goncalves, Josemary A.C.; Botelho, Suzana; Tobias, Carmen C.B.; Ridenti, Marco A.; Pascholati, Paulo R.; Fonte, Paulo; Mangiarotti, Alessio
2009-01-01
In this work we present the preliminary studies of the first Townsend coefficient behavior in isobutane for reduced electric fields ranging from 173 Td up to 281 Td by means of signal amplitude analysis. The measurements were based on the Pulsed Townsend technique. The experimental setup consists of two parallel plates housed in a stainless steel chamber at gas flow regime. In our configuration, the primary electrons are produced by irradiating the cathode with a fast nitrogen laser (700 ps pulse duration). In order to validate the technique and to analyze effects of non-uniformity, results for nitrogen are also presented. (author)
International Nuclear Information System (INIS)
Tsuji, Masashi; Aoki, Yukinori; Shimazu, Yoichiro; Yamasaki, Masatoshi; Hanayama, Yasushi
2006-01-01
A method to evaluate the moderator coefficient (MTC) and the Doppler coefficient through experimental procedures performed during reactor physics tests of PWR power plants is proposed. This method combines isothermal temperature coefficient (ITC) measurement experiments and reactor power transient experiments at low power conditions for dynamic identification. In the dynamic identification, either one of temperature coefficients can be determined in such a way that frequency response characteristics of the reactivity change observed by a digital reactivity meter is reproduced from measured data of neutron count rate and the average coolant temperature. The other unknown coefficient can also be determined by subtracting the coefficient obtained from the dynamic identification from ITC. As the proposed method can directly estimate the Doppler coefficient, the applicability of the conventional core design codes to predict the Doppler coefficient can be verified for new types of fuels such as mixed oxide fuels. The digital simulation study was carried out to show the feasibility of the proposed method. The numerical analysis showed that the MTC and the Doppler coefficient can be estimated accurately and even if there are uncertainties in the parameters of the reactor kinetics model, the accuracies of the estimated values are not seriously impaired. (author)
Eldridge, Jeffrey I.; Spuckler, Charles M.; Markham, James R.
2009-01-01
The temperature dependence of the scattering and absorption coefficients for a set of freestanding plasma-sprayed 8 wt% yttria-stabilized zirconia (8YSZ) thermal barrier coatings (TBCs) was determined at temperatures up to 1360 C in a wavelength range from 1.2 micrometers up to the 8YSZ absorption edge. The scattering and absorption coefficients were determined by fitting the directional-hemispherical reflectance and transmittance values calculated by a four-flux Kubelka Munk method to the experimentally measured hemispherical-directional reflectance and transmittance values obtained for five 8YSZ thicknesses. The scattering coefficient exhibited a continuous decrease with increasing wavelength and showed no significant temperature dependence. The scattering is primarily attributed to the relatively temperature-insensitive refractive index mismatch between the 8YSZ and its internal voids. The absorption coefficient was very low (less than 1 per centimeter) at wavelengths between 2 micrometers and the absorption edge and showed a definite temperature dependence that consisted of a shift of the absorption edge to shorter wavelengths and an increase in the weak absorption below the absorption edge with increasing temperature. The shift in the absorption edge with temperature is attributed to strongly temperature-dependent multiphonon absorption. While TBC hemispherical transmittance beyond the absorption edge can be predicted by a simple exponential decrease with thickness, below the absorption edge, typical TBC thicknesses are well below the thickness range where a simple exponential decrease in hemispherical transmittance with TBC thickness is expected. [Correction added after online publication August 11, 2009: "edge to a shorter wavelengths" has been updated as edge to shorter wavelengths."
International Nuclear Information System (INIS)
Zhang Yong; Baturin, Ivan S.; Aulbach, Emil; Lupascu, Doru C.; Kholkin, Andrei L.; Shur, Vladimir Ya.; Roedel, Juergen
2005-01-01
Hysteresis loops of the piezoelectric coefficient, d 33 =f(E 3 ), are measured on virgin and fatigued lead zirconate titanate ceramics. Four parameters are directly extracted from the measurements: internal bias field E b , offset piezoelectric coefficient d offset , coercive field E c , and remnant piezoelectric coefficient d r . The reduction in d r displays the decreasing switchable polarization with fatigue cycling. E b and d offset are found to be linearly related. After thermal annealing, both offsets disappear, while the increase in E c and the reduction in d r withstand annealing. The microscopic entities responsible for the offsets are less stable than those for reduced switching
Fell, T P
2007-01-01
The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts--the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES.
International Nuclear Information System (INIS)
Fell, T.P.
2007-01-01
The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts - the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. (author)
International Trade. International Business
Мохнюк, А. М.; Mokhniuk, A. M.
2015-01-01
Work programme of the study course “International Trade. International Business” was prepared in accordance with educational and vocational training program for bachelors of training direction 6.030601 “Management”.
Criterions for fixing regulatory seismic acceleration coefficients
International Nuclear Information System (INIS)
Costes, D.
1988-03-01
Acceleration coeffficients to be taken into account in seismic areas for calculation of structures are defined in national seismic regulations. Joined to the described qualitative requirements, these coefficients represent a balance between precaution costs and avoided damages, both in terms of material repairing costs and damage to human life. Persons in charge of fixing these coefficients must be informed of corresponding quantitative aspects. Data on seismic motions occurrencies and consequences are gathered here and convoluted to mean damage evaluations. Indications on precaution costs are joined, which shows that currently recommended levels of seismic motions are high relatively to financial profitability, and represent in fact an aethical choice about human life value [fr
Diffusion and transport coefficients in synthetic opals
International Nuclear Information System (INIS)
Sofo, J. O.; Mahan, G. D.
2000-01-01
Opals are structures composed of close-packed spheres in the size range of nano to micrometers. They are sintered to create small necks at the points of contact. We have solved the diffusion problem in such structures. The relation between the diffusion coefficient and the thermal and electrical conductivity is used to estimate the transport coefficients of opal structures as a function of the neck size and the mean free path of the carriers. The theory presented is also applicable to the diffusion problem in other periodic structures. (c) 2000 The American Physical Society
A Simple Measure of Price Adjustment Coefficients.
Damodaran, Aswath
1993-01-01
One measure of market efficiency is the speed with which prices adjust to new information. The author develops a simple approach to estimating these price adjustment coefficients by using the information in return processes. This approach is used to estimate t he price adjustment coefficients for firms listed on the NYSE and the A MEX as well as for over-the-counter stocks. The author finds evidence of a lagged adjustment to new information in shorter return intervals for firms in all market ...
Reaction rate calculations via transmission coefficients
International Nuclear Information System (INIS)
Feit, M.D.; Alder, B.J.
1985-01-01
The transmission coefficient of a wavepacket traversing a potential barrier can be determined by steady state calculations carried out in imaginary time instead of by real time dynamical calculations. The general argument is verified for the Eckart barrier potential by a comparison of transmission coefficients calculated from real and imaginary time solutions of the Schroedinger equation. The correspondence demonstrated here allows a formulation for the reaction rate that avoids difficulties due to both rare events and explicitly time dependent calculations. 5 refs., 2 figs
Dependence of sputtering coefficient on ion dose
International Nuclear Information System (INIS)
Colligon, J.S.; Patel, M.H.
1977-01-01
The sputtering coefficient of polycrystalline gold bombarded by 10-40 keV Ar + ions had been measured as a function of total ion dose and shown to exhibit oscillations in magnitude between 30 and 100%. Possible experimental errors which would give rise to such an oscillation have been considered, but it is apparent that these factors are unable to explain the measurements. It is proposed that a change in the Sublimation Energy associated with either bulk damage or formation of surface topographical features arising during ion bombardment may be responsible for the observed variations in sputtering coefficient. (author)
ANL results for LMFR reactivity coefficients benchmark
International Nuclear Information System (INIS)
Hill, Robert
2000-01-01
The fast reactor analysis methods developed at ANL were extensively tested in ZPR and ZPPR experiments, applied to EBR-2 and FFTF test reactors. The basic nuclear data library used was ENDF/B-V.2 with the ETOE-2 data processing code and the ENDF/B-VI. Multigroup constants were generated by Monte Carlo code MCNP 2 -2. Neutron flux calculation were done by DIF3D code applying neutron diffusion theory and finite difference method. The results obtained include basic parameters; fuel and structure regional Doppler coefficients; geometry expansion fuel coefficients; kinetics parameters. In general, agreement between phase 1 and 2 results were excellent
Measurements of the Drag Coefficient of Simulated Micrometeoroids
DeLuca, M.; Munsat, T.; Sternovsky, Z.
2017-12-01
The dust accelerator facility operated at the University of Colorado is used to simulate meteoric ablation, including measuring the ionization efficiency over a wide range of velocities (e.g., DeLuca et al., Planet. Space Sci., submitted, 2017). This presentation reports on the most recent experimental measurements of the drag coefficient that determines the particles' slowdown from their frictional interaction with the atmosphere. The measurements indicate that meteors experience considerably more slowdown than usually assumed. The simulated meteors consisted of submicron sized aluminum particles shot into an air chamber held at 200 mTorr pressure at velocities between 1 - 10 km/s using the dust accelerator and meteor ablation facility. The slowdown is calculated from precise timing measurements made using pickup tube detectors placed upstream and near the entrance to the air chamber, and an impact detector inside the air chamber at the downstream end of the chamber. Supporting modeling calculations show that the particles have little or no mass loss during their interaction with air and thus constant radius can be assumed. Preliminary results for the drag coefficient calculated from these timing measurements reveal that the aluminum particles have a drag coefficient of 1.51 ± 0.24 in air, which is higher than typically assumed in meteoric ablation models (usually 0.5 to 1), indicating that meteors may experience more air drag than previously assumed. More detailed measurements over a wider parameter range are underway.
The Parameters Affect on Power Coefficient Vertical Axis Wind Turbine
Directory of Open Access Journals (Sweden)
Ahmed Y. Qasim
2012-04-01
Full Text Available ABSTRACT: This study describes the design of a special type of vertical axis rotor wind turbine with moveable vertically positioned vanes. The novel design increases the torque in the left side of the wind turbine by increasing the drag coefficient. It also reduces the negative torque of the frame which rotates contrary to the wind in the other side. Two different types of models, having different vane shapes (flat vane and cavity shaped vane, were fabricated. Each type consisted of two models with varying number of frames (three and four frames. The models were tested in a wind tunnel with variable wind speed in order to understand the effect of shape, weight, and number of frames on the power coefficient of the wind turbine. ABSTRAK: Di dalam kajian ini, rotor turbin angin berpaksi vertikel sebagai rangka khusus telah direkabentuk dengan lokasi vertikel mudahalih oleh bilah kipas. Rekabentuk ini meningkatkan tork di bahagian kiri turbin angin dengan meningkatkan pekali seretan dan mengurangkan tork negatif rangka yang berputar berlawanan dengan angin pada bahagian lain. Dua jenis model berbentuk berlainan telah difabrikasi (bilah kipas rata dan bilah kipas berbentuk kaviti, dengan setiap jenis mempunyai dua model dengan bilangan rangka yang berlainan (berangka tiga dan berangka empat. Model-model telah diuji di dalam terowong angin dengan kelajuan angin yang berbeza bagi mendapatkan kesan rekabentuk, berat dan bilangan rangka ke atas pekali kuasa.KEYWORDS: design; wind turbine; drag coefficient; vane
The coefficient of restitution of pressurized balls: a mechanistic model
Georgallas, Alex; Landry, Gaëtan
2016-01-01
Pressurized, inflated balls used in professional sports are regulated so that their behaviour upon impact can be anticipated and allow the game to have its distinctive character. However, the dynamics governing the impacts of such balls, even on stationary hard surfaces, can be extremely complex. The energy transformations, which arise from the compression of the gas within the ball and from the shear forces associated with the deformation of the wall, are examined in this paper. We develop a simple mechanistic model of the dependence of the coefficient of restitution, e, upon both the gauge pressure, P_G, of the gas and the shear modulus, G, of the wall. The model is validated using the results from a simple series of experiments using three different sports balls. The fits to the data are extremely good for P_G > 25 kPa and consistent values are obtained for the value of G for the wall material. As far as the authors can tell, this simple, mechanistic model of the pressure dependence of the coefficient of restitution is the first in the literature. *%K Coefficient of Restitution, Dynamics, Inflated Balls, Pressure, Impact Model
Experimental Investigation of Discharge Coefficient in Mesh Panel Bottom Intakes
Directory of Open Access Journals (Sweden)
keivan bina
2012-04-01
Full Text Available Bottom racks is a hydraulic structure which is placed in the bed of stream through which, part of flow in the main channel is diverted. These structures have very wide application in industry, irrigation, drainage and etc. Of course much attention had been paid to the study of such structures, but characteristics of flow through bottom racks are complex. The present study was directed to estimate the discharge coefficient of a new kind of bottom racks including both transverse and longitudinal bars that named "mesh panel racks" without considering any solids in the fluid. This kind of bottom intake has advantages from structural point of view and has less deformation under static and dynamic loads. Laboratory setup with three mesh panel intakes was built and the effects of various parameters such as racks slope, porosity and geometry were explored. A dimensional analysis using Buckingham theory showed the effective hydraulic and geometric factors that affect the discharge coefficient (Cd of bottom racks. Then, a statistical approach to determine the discharge coefficient of a rack structure was developed with linear and nonlinear regression using SPSS software. The efficiency of the proposed technique is high enough that the associated error is limited to 10%. Finally, hydraulic performance of mesh panel intakes was compared with regular type of bottom intakes, which consist of longitudinal bars. For this purpose, diverted discharge through both type of intakes calculated in same situation
Consistency in the World Wide Web
DEFF Research Database (Denmark)
Thomsen, Jakob Grauenkjær
Tim Berners-Lee envisioned that computers will behave as agents of humans on the World Wide Web, where they will retrieve, extract, and interact with information from the World Wide Web. A step towards this vision is to make computers capable of extracting this information in a reliable...... and consistent way. In this dissertation we study steps towards this vision by showing techniques for the specication, the verication and the evaluation of the consistency of information in the World Wide Web. We show how to detect certain classes of errors in a specication of information, and we show how...... the World Wide Web, in order to help perform consistent evaluations of web extraction techniques. These contributions are steps towards having computers reliable and consistently extract information from the World Wide Web, which in turn are steps towards achieving Tim Berners-Lee's vision. ii...
Consistent histories and operational quantum theory
International Nuclear Information System (INIS)
Rudolph, O.
1996-01-01
In this work a generalization of the consistent histories approach to quantum mechanics is presented. We first critically review the consistent histories approach to nonrelativistic quantum mechanics in a mathematically rigorous way and give some general comments about it. We investigate to what extent the consistent histories scheme is compatible with the results of the operational formulation of quantum mechanics. According to the operational approach, nonrelativistic quantum mechanics is most generally formulated in terms of effects, states, and operations. We formulate a generalized consistent histories theory using the concepts and the terminology which have proven useful in the operational formulation of quantum mechanics. The logical rule of the logical interpretation of quantum mechanics is generalized to the present context. The algebraic structure of the generalized theory is studied in detail
Self-consistent areas law in QCD
International Nuclear Information System (INIS)
Makeenko, Yu.M.; Migdal, A.A.
1980-01-01
The problem of obtaining the self-consistent areas law in quantum chromodynamics (QCD) is considered from the point of view of the quark confinement. The exact equation for the loop average in multicolor QCD is reduced to a bootstrap form. Its iterations yield new manifestly gauge invariant perturbation theory in the loop space, reproducing asymptotic freedom. For large loops, the areas law apprears to be a self-consistent solution
Consistency of the MLE under mixture models
Chen, Jiahua
2016-01-01
The large-sample properties of likelihood-based statistical inference under mixture models have received much attention from statisticians. Although the consistency of the nonparametric MLE is regarded as a standard conclusion, many researchers ignore the precise conditions required on the mixture model. An incorrect claim of consistency can lead to false conclusions even if the mixture model under investigation seems well behaved. Under a finite normal mixture model, for instance, the consis...
NGA-West 2 GMPE average site coefficients for use in earthquake-resistant design
Borcherdt, Roger D.
2015-01-01
Site coefficients corresponding to those in tables 11.4–1 and 11.4–2 of Minimum Design Loads for Buildings and Other Structures published by the American Society of Civil Engineers (Standard ASCE/SEI 7-10) are derived from four of the Next Generation Attenuation West2 (NGA-W2) Ground-Motion Prediction Equations (GMPEs). The resulting coefficients are compared with those derived by other researchers and those derived from the NGA-West1 database. The derivation of the NGA-W2 average site coefficients provides a simple procedure to update site coefficients with each update in the Maximum Considered Earthquake Response MCER maps. The simple procedure yields average site coefficients consistent with those derived for site-specific design purposes. The NGA-W2 GMPEs provide simple scale factors to reduce conservatism in current simplified design procedures.
Friction Coefficient Determination by Electrical Resistance Measurements
Tunyagi, A.; Kandrai, K.; Fülöp, Z.; Kapusi, Z.; Simon, A.
2018-01-01
A simple and low-cost, DIY-type, Arduino-driven experiment is presented for the study of friction and measurement of the friction coefficient, using a conductive rubber cord as a force sensor. It is proposed for high-school or college/university-level students. We strongly believe that it is worthwhile planning, designing and performing Arduino…
Tracking time-varying coefficient-functions
DEFF Research Database (Denmark)
Nielsen, Henrik Aalborg; Nielsen, Torben Skov; Joensen, Alfred K.
2000-01-01
is a combination of recursive least squares with exponential forgetting and local polynomial regression. It is argued, that it is appropriate to let the forgetting factor vary with the value of the external signal which is the argument of the coefficient functions. Some of the key properties of the modified method...... are studied by simulation...
On finding algebraic expressions for genealogical coefficients
International Nuclear Information System (INIS)
Kanyauskas, J.M.; Shimonis, V.Ch.; Rudzikas, Z.B.
1979-01-01
It has been attempted to obtain analytical expressions for genealogical coefficients with one detached electron in the case of L-S coupling. A method of second quantization and tensorial properties of the quasi-spin operator are applied. It is restricted to the states for the classification of which the seigniority quantum number v is sufficient. Three ways of the acquirement of these expressions are discussed: 1. In the recurrent way wave functions of N and N-1 electrons are built, consequently expressing these functions in terms of the creation-annihilation operators. 2. Recurrent summation with the use of evident, simple genealogical coefficients. 3. Using the ratios, connecting the genealogical coefficients with the normalized multiplier. The data are presented in formulae and discussions. The generalization of the Redmond's formula is obtained and relatively simple algebraic expressions of the genealogical coefficients of the equivalent electron configurations, for the distinction of the recurrent terms of which introduction of the seigniority quantum number v is sufficient, are given
Power coefficient anomaly in Joyo, (2)
International Nuclear Information System (INIS)
Ishikawa, Makoto; Yamashita, Yoshioki; Sasaki, Makoto; Nara, Yoshihiko.
1981-12-01
In this report, the presumption about the mechanism having caused the power coefficient anomaly in Joyo during the 75 MW power-raising test in 1979 is described. After the previous report, the new information about the results of the post-irradiation examination and the analysis of the power coefficient of Joyo were able to be obtained. From these information, the mechanism of causing the anomaly was presumed as follows. In 50 MW operation, the fuel burnup reached about 10,000 MWD/ton at the end of second cycle, and produced fission gas was almost retained in fuel pellets. When the power was raised from 50 MW to 75 MW for the first time, the fission gas began to be released when 50 MW was somewhat exceeded. The fission gas release caused the temperature rise and cracking of fuel pellets, and elongated fuel stack length abruptly. These phenomena induced to enlarge the fuel expansion reactivity effect and Doppler reactivity effect, and caused the anomalous behavior of power coefficient. After reaching 75 MW, the fuel stack length did not respond normally to reactor power change, and the magnitude of power coefficient became smaller. The reactivity was lost considerably from the core after the anomaly. (Kako, I.)
Problems on Divisibility of Binomial Coefficients
Osler, Thomas J.; Smoak, James
2004-01-01
Twelve unusual problems involving divisibility of the binomial coefficients are represented in this article. The problems are listed in "The Problems" section. All twelve problems have short solutions which are listed in "The Solutions" section. These problems could be assigned to students in any course in which the binomial theorem and Pascal's…
Effective stress coefficient for uniaxial strain condition
DEFF Research Database (Denmark)
Alam, M.M.; Fabricius, I.L.
2012-01-01
one dimensional rock mechanical deformation. We further investigated the effect of boundary condition on the stress dependency of effective stress coefficient and discussed its application in reservoir study. As stress field in the reservoirs are most unlikely to be hydrostatic, effective stress...... determined under uniaxial strain condition will be more relevant in reservoir studies. Copyright 2012 ARMA, American Rock Mechanics Association....
Molecular Diffusion Coefficients: Experimental Determination and Demonstration.
Fate, Gwendolyn; Lynn, David G.
1990-01-01
Presented are laboratory methods which allow the demonstration and determination of the diffusion coefficients of compounds ranging in size from water to small proteins. Included are the procedures involving the use of a spectrometer, UV cell, triterated agar, and oxygen diffusion. Results including quantification are described. (CW)
Absorption coefficients of silicon: A theoretical treatment
Tsai, Chin-Yi
2018-05-01
A theoretical model with explicit formulas for calculating the optical absorption and gain coefficients of silicon is presented. It incorporates direct and indirect interband transitions and considers the effects of occupied/unoccupied carrier states. The indirect interband transition is calculated from the second-order time-independent perturbation theory of quantum mechanics by incorporating all eight possible routes of absorption or emission of photons and phonons. Absorption coefficients of silicon are calculated from these formulas. The agreements and discrepancies among the calculated results, the Rajkanan-Singh-Shewchun (RSS) formula, and Green's data are investigated and discussed. For example, the RSS formula tends to overestimate the contributions of indirect transitions for cases with high photon energy. The results show that the state occupied/unoccupied effect is almost negligible for silicon absorption coefficients up to the onset of the optical gain condition where the energy separation of Quasi-Femi levels between electrons and holes is larger than the band-gap energy. The usefulness of using the physics-based formulas, rather than semi-empirical fitting ones, for absorption coefficients in theoretical studies of photovoltaic devices is also discussed.
Control in the coefficients with variational crimes
DEFF Research Database (Denmark)
Evgrafov, Anton; Marhadi, Kun Saptohartyadi
2012-01-01
We study convergence of discontinuous Galerkin-type discretizations of the problems of control in the coefficients of uniformly elliptic partial differential equations (PDEs). As a model problem we use that of the optimal design of thin (Kirchhoff) plates, where the governing equations...
Coefficient Omega Bootstrap Confidence Intervals: Nonnormal Distributions
Padilla, Miguel A.; Divers, Jasmin
2013-01-01
The performance of the normal theory bootstrap (NTB), the percentile bootstrap (PB), and the bias-corrected and accelerated (BCa) bootstrap confidence intervals (CIs) for coefficient omega was assessed through a Monte Carlo simulation under conditions not previously investigated. Of particular interests were nonnormal Likert-type and binary items.…
Activity risk coefficients for living generations
International Nuclear Information System (INIS)
Raicevic, J.; Merkle, M.; Ninkovic, M. M.
1993-01-01
This paper deals with the new concept of the Activity risk coefficients, ARCs, which are in Probabilistic risk assessment PRA computer codes used for the calculation of the stochastic effects due to low dose exposures. As an example, ARC expressions for the Cloudshine is derived. (author)
Rate coefficient for the reaction N + NO
Fox, J. L.
1994-01-01
Evidence has been advanced that the rate coefficient for the reaction N + NO right arrow N2 + O has a small positive temperature dependence at the high temperatures (900 to 1500 K) that prevail in the terrestrial middle and upper thermosphere by Siskind and Rusch (1992), and at the low temperatures (100 to 200 K) of the Martian lower thermosphere by Fox (1993). Assuming that the rate coefficient recommended by the Jet Propulsion Laboratory evaluation (DeMore et al., 1992) is accurate at 300 K, we derive here the low temperature value of the activation energy for this reaction and thus the rate coefficient that best fits the Viking 1 measured NO densities. We find that the fit is acceptable for a rate coefficient of about 1.3 x 10(exp -10)(T/300)(exp 0.5)exp(-400/T) and better for a value of about 2.5 x 10(exp -10)(T/300)(exp 0.5)exp(-600/T)cu cm/s.
The Evolution of Pearson's Correlation Coefficient
Kader, Gary D.; Franklin, Christine A.
2008-01-01
This article describes an activity for developing the notion of association between two quantitative variables. By exploring a collection of scatter plots, the authors propose a nonstandard "intuitive" measure of association; and by examining properties of this measure, they develop the more standard measure, Pearson's Correlation Coefficient. The…
Correlation Coefficients: Appropriate Use and Interpretation.
Schober, Patrick; Boer, Christa; Schwarte, Lothar A
2018-05-01
Correlation in the broadest sense is a measure of an association between variables. In correlated data, the change in the magnitude of 1 variable is associated with a change in the magnitude of another variable, either in the same (positive correlation) or in the opposite (negative correlation) direction. Most often, the term correlation is used in the context of a linear relationship between 2 continuous variables and expressed as Pearson product-moment correlation. The Pearson correlation coefficient is typically used for jointly normally distributed data (data that follow a bivariate normal distribution). For nonnormally distributed continuous data, for ordinal data, or for data with relevant outliers, a Spearman rank correlation can be used as a measure of a monotonic association. Both correlation coefficients are scaled such that they range from -1 to +1, where 0 indicates that there is no linear or monotonic association, and the relationship gets stronger and ultimately approaches a straight line (Pearson correlation) or a constantly increasing or decreasing curve (Spearman correlation) as the coefficient approaches an absolute value of 1. Hypothesis tests and confidence intervals can be used to address the statistical significance of the results and to estimate the strength of the relationship in the population from which the data were sampled. The aim of this tutorial is to guide researchers and clinicians in the appropriate use and interpretation of correlation coefficients.
Modelling of power-reactivity coefficient measurement
International Nuclear Information System (INIS)
Strmensky, C.; Petenyi, V.; Jagrik, J.; Minarcin, M.; Hascik, R.; Toth, L.
2005-01-01
Report describes results of modeling of power-reactivity coefficient analysis on power-level. In paper we calculate values of discrepancies arisen during transient process. These discrepancies can be arisen as result of experiment evaluation and can be caused by disregard of 3D effects on neutron distribution. The results are critically discussed (Authors)
Regularity of the Interband Light Absorption Coefficient
Indian Academy of Sciences (India)
In this paper we consider the interband light absorption coefficient (ILAC), in a symmetric form, in the case of random operators on the -dimensional lattice. We show that the symmetrized version of ILAC is either continuous or has a component which has the same modulus of continuity as the density of states.
DEFF Research Database (Denmark)
Jeong, Cheol-Ho; Chang, Ji-ho
2015-01-01
largely depending on the test room. Several conversion methods for porous absorbers from the Sabine absorption coefficient to the random incidence absorption coefficient were suggested by considering the finite size of a test specimen and non-uniformly incident energy onto the specimen, which turned out...... resistivity optimization outperforms the surface impedance optimization in terms of the reproducibility....
Mohammed, Ahmed; Zeleke, Aklilu
2015-01-01
We introduce a class of second-order ordinary differential equations (ODEs) with variable coefficients whose closed-form solutions can be obtained by the same method used to solve ODEs with constant coefficients. General solutions for the homogeneous case are discussed.
Drag coefficient Variability and Thermospheric models
Moe, Kenneth
Satellite drag coefficients depend upon a variety of factors: The shape of the satellite, its altitude, the eccentricity of its orbit, the temperature and mean molecular mass of the ambient atmosphere, and the time in the sunspot cycle. At altitudes where the mean free path of the atmospheric molecules is large compared to the dimensions of the satellite, the drag coefficients can be determined from the theory of free-molecule flow. The dependence on altitude is caused by the concentration of atomic oxygen which plays an important role by its ability to adsorb on the satellite surface and thereby affect the energy loss of molecules striking the surface. The eccentricity of the orbit determines the satellite velocity at perigee, and therefore the energy of the incident molecules relative to the energy of adsorption of atomic oxygen atoms on the surface. The temperature of the ambient atmosphere determines the extent to which the random thermal motion of the molecules influences the momentum transfer to the satellite. The time in the sunspot cycle affects the ambient temperature as well as the concentration of atomic oxygen at a particular altitude. Tables and graphs will be used to illustrate the variability of drag coefficients. Before there were any measurements of gas-surface interactions in orbit, Izakov and Cook independently made an excellent estimate that the drag coefficient of satellites of compact shape would be 2.2. That numerical value, independent of altitude, was used by Jacchia to construct his model from the early measurements of satellite drag. Consequently, there is an altitude dependent bias in the model. From the sparce orbital experiments that have been done, we know that the molecules which strike satellite surfaces rebound in a diffuse angular distribution with an energy loss given by the energy accommodation coefficient. As more evidence accumulates on the energy loss, more realistic drag coefficients are being calculated. These improved drag
Energy Technology Data Exchange (ETDEWEB)
Spielmann, V.; Li, W.B.; Zankl, M.; Oeh, U.
2015-11-15
The dose coefficients used in nuclear medicine for dose calculations of radiopharmaceuticals are based on recommendations by ICRP (International Commission on radiological protection) and the MIRD (Medical Internal Radiation Dose Committee) using mathematical models for the temporal activity distributions in organs and tissues (biokinetic models) and mathematical models of the human body. These models using an idealized human body do not include uncertainty estimations. The research project is aimed to determine the uncertainties and thus the reliability of the dose coefficients for radiopharmaceuticals and to identify the biokinetic and dosimetric parameters that contribute most of the uncertainties.
Measurement of particle transport coefficients on Alcator C-Mod
International Nuclear Information System (INIS)
Luke, T.C.T.
1994-10-01
The goal of this thesis was to study the behavior of the plasma transport during the divertor detachment in order to explain the central electron density rise. The measurement of particle transport coefficients requires sophisticated diagnostic tools. A two color interferometer system was developed and installed on Alcator C-Mod to measure the electron density with high spatial (∼ 2 cm) and high temporal (≤ 1.0 ms) resolution. The system consists of 10 CO 2 (10.6 μm) and 4 HeNe (.6328 μm) chords that are used to measure the line integrated density to within 0.08 CO 2 degrees or 2.3 x 10 16 m -2 theoretically. Using the two color interferometer, a series of gas puffing experiments were conducted. The density was varied above and below the threshold density for detachment at a constant magnetic field and plasma current. Using a gas modulation technique, the particle diffusion, D, and the convective velocity, V, were determined. Profiles were inverted using a SVD inversion and the transport coefficients were extracted with a time regression analysis and a transport simulation analysis. Results from each analysis were in good agreement. Measured profiles of the coefficients increased with the radius and the values were consistent with measurements from other experiments. The values exceeded neoclassical predictions by a factor of 10. The profiles also exhibited an inverse dependence with plasma density. The scaling of both attached and detached plasmas agreed well with this inverse scaling. This result and the lack of change in the energy and impurity transport indicate that there was no change in the underlying transport processes after detachment
Measurement of particle transport coefficients on Alcator C-Mod
Energy Technology Data Exchange (ETDEWEB)
Luke, T.C.T.
1994-10-01
The goal of this thesis was to study the behavior of the plasma transport during the divertor detachment in order to explain the central electron density rise. The measurement of particle transport coefficients requires sophisticated diagnostic tools. A two color interferometer system was developed and installed on Alcator C-Mod to measure the electron density with high spatial ({approx} 2 cm) and high temporal ({le} 1.0 ms) resolution. The system consists of 10 CO{sub 2} (10.6 {mu}m) and 4 HeNe (.6328 {mu}m) chords that are used to measure the line integrated density to within 0.08 CO{sub 2} degrees or 2.3 {times} 10{sup 16}m{sup {minus}2} theoretically. Using the two color interferometer, a series of gas puffing experiments were conducted. The density was varied above and below the threshold density for detachment at a constant magnetic field and plasma current. Using a gas modulation technique, the particle diffusion, D, and the convective velocity, V, were determined. Profiles were inverted using a SVD inversion and the transport coefficients were extracted with a time regression analysis and a transport simulation analysis. Results from each analysis were in good agreement. Measured profiles of the coefficients increased with the radius and the values were consistent with measurements from other experiments. The values exceeded neoclassical predictions by a factor of 10. The profiles also exhibited an inverse dependence with plasma density. The scaling of both attached and detached plasmas agreed well with this inverse scaling. This result and the lack of change in the energy and impurity transport indicate that there was no change in the underlying transport processes after detachment.
Modeling of the substrate and product transfer coefficients for ethanol fermentation
International Nuclear Information System (INIS)
Zerajic, S.; Grbavcic, Z.; Savkovic-Stevanovic, J.
2008-01-01
The transfer phenomena of the substrate and product for ethanol fermentation with immobilized biocatalyst were investigated. Fermentation was carried out with a biocatalyst consisting of Ca-alginate gel in the form of two-layer spherical beads in anaerobic conditions. The determination of kinetic parameters was achieved by fitting bioreaction progress curves to the experimental data. The calculation of the diffusion coefficients was performed by numerical methods for experimental conditions. Finally, the glucose and ethanol transfer coefficients are defined and determined, using the effective diffusion coefficients. (Abstract Copyright [2008], Wiley Periodicals, Inc.)
Chao, Keh-Ping; Wang, Ping; Wang, Ya-Ting
2007-04-02
The chemical resistance of eight organic solvents in high density polyethylene (HDPE) geomembrane has been investigated using the ASTM F739 permeation method and the immersion test at different temperatures. The diffusion of the experimental organic solvents in HDPE geomembrane was non-Fickian kinetic, and the solubility coefficients can be consistent with the solubility parameter theory. The diffusion coefficients and solubility coefficients determined by the ASTM F739 method were significantly correlated to the immersion tests (pHDPE as barriers in the field.
Effect of Interband Interaction on Isotope Effect Coefficient of Mg B2 Superconductors
International Nuclear Information System (INIS)
Udomsamuthirun, P.; Kumvongsa, C.; Burakorn, A.; Changkanarth, P.; Maneeratanakul, S.
2005-10-01
In this research, the exact formula of Tc s equation and the isotope effect coefficient of two-band s-wave superconductors in weak-coupling limit are derived by considering the influence of interband interaction .In each band ,our model consist of two paring interactions : the electron-phonon interaction and non-electron-phonon interaction . According to the numerical calculation, we find that the isotope effect coefficient of MgB 2 , α=3 . 0 with T c 40 K can be found in the weak coupling regime and interband interaction of electron-phonon show more effect on isotope effect coefficient than interband interaction of non-phonon-electron