DOE Office of Scientific and Technical Information (OSTI.GOV)
Vondy, D.R.; Fowler, T.B.; Cunningham, G.W.
1975-10-01
The computer code block VENTURE, designed to solve multigroup neutronics problems with application of the finite-difference diffusion-theory approximation to neutron transport (or alternatively simple P$sub 1$) in up to three- dimensional geometry is described. A variety of types of problems may be solved: the usual eigenvalue problem, a direct criticality search on the buckling, on a reciprocal velocity absorber (prompt mode), or on nuclide concentrations, or an indirect criticality search on nuclide concentrations, or on dimensions. First- order perturbation analysis capability is available at the macroscopic cross section level. (auth)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kavanagh, D.L.; Antchagno, M.J.; Egawa, E.K.
1960-12-31
Operating instructions are presented for DMM, a Remington Rand 1103A program using one-space-dimensional multigroup diffusion theory to calculate the reactivity or critical conditions and flux distribution of a multiregion reactor. Complete descriptions of the routines and problem input and output specifications are also included. (D.L.C.)
Development of a SCALE Tool for Continuous-Energy Eigenvalue Sensitivity Coefficient Calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perfetti, Christopher M; Rearden, Bradley T
2013-01-01
Two methods for calculating eigenvalue sensitivity coefficients in continuous-energy Monte Carlo applications were implemented in the KENO code within the SCALE code package. The methods were used to calculate sensitivity coefficients for several criticality safety problems and produced sensitivity coefficients that agreed well with both reference sensitivities and multigroup TSUNAMI-3D sensitivity coefficients. The newly developed CLUTCH method was observed to produce sensitivity coefficients with high figures of merit and low memory requirements, and both continuous-energy sensitivity methods met or exceeded the accuracy of the multigroup TSUNAMI-3D calculations.
MC 2 -3: Multigroup Cross Section Generation Code for Fast Reactor Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Changho; Yang, Won Sik
This paper presents the methods and performance of the MC2 -3 code, which is a multigroup cross-section generation code for fast reactor analysis, developed to improve the resonance self-shielding and spectrum calculation methods of MC2 -2 and to simplify the current multistep schemes generating region-dependent broad-group cross sections. Using the basic neutron data from ENDF/B data files, MC2 -3 solves the consistent P1 multigroup transport equation to determine the fundamental mode spectra for use in generating multigroup neutron cross sections. A homogeneous medium or a heterogeneous slab or cylindrical unit cell problem is solved in ultrafine (2082) or hyperfine (~400more » 000) group levels. In the resolved resonance range, pointwise cross sections are reconstructed with Doppler broadening at specified temperatures. The pointwise cross sections are directly used in the hyperfine group calculation, whereas for the ultrafine group calculation, self-shielded cross sections are prepared by numerical integration of the pointwise cross sections based upon the narrow resonance approximation. For both the hyperfine and ultrafine group calculations, unresolved resonances are self-shielded using the analytic resonance integral method. The ultrafine group calculation can also be performed for a two-dimensional whole-core problem to generate region-dependent broad-group cross sections. Verification tests have been performed using the benchmark problems for various fast critical experiments including Los Alamos National Laboratory critical assemblies; Zero-Power Reactor, Zero-Power Physics Reactor, and Bundesamt für Strahlenschutz experiments; Monju start-up core; and Advanced Burner Test Reactor. Verification and validation results with ENDF/B-VII.0 data indicated that eigenvalues from MC2 -3/DIF3D agreed well with Monte Carlo N-Particle5 MCNP5 or VIM Monte Carlo solutions within 200 pcm and regionwise one-group fluxes were in good agreement with Monte Carlo solutions.« less
A multigroup radiation diffusion test problem: Comparison of code results with analytic solution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shestakov, A I; Harte, J A; Bolstad, J H
2006-12-21
We consider a 1D, slab-symmetric test problem for the multigroup radiation diffusion and matter energy balance equations. The test simulates diffusion of energy from a hot central region. Opacities vary with the cube of the frequency and radiation emission is given by a Wien spectrum. We compare results from two LLNL codes, Raptor and Lasnex, with tabular data that define the analytic solution.
The Problem of Convergence and Commitment in Multigroup Evaluation Planning.
ERIC Educational Resources Information Center
Hausken, Chester A.
This paper outlines a model for multigroup evaluation planning in a rural-education setting wherein the commitment to the structure necessary to evaluate a program is needed on the part of a research and development laboratory, the state departments of education, county supervisors, and the rural schools. To bridge the gap between basic research,…
NASA Astrophysics Data System (ADS)
Nelson, Adam
Multi-group scattering moment matrices are critical to the solution of the multi-group form of the neutron transport equation, as they are responsible for describing the change in direction and energy of neutrons. These matrices, however, are difficult to correctly calculate from the measured nuclear data with both deterministic and stochastic methods. Calculating these parameters when using deterministic methods requires a set of assumptions which do not hold true in all conditions. These quantities can be calculated accurately with stochastic methods, however doing so is computationally expensive due to the poor efficiency of tallying scattering moment matrices. This work presents an improved method of obtaining multi-group scattering moment matrices from a Monte Carlo neutron transport code. This improved method of tallying the scattering moment matrices is based on recognizing that all of the outgoing particle information is known a priori and can be taken advantage of to increase the tallying efficiency (therefore reducing the uncertainty) of the stochastically integrated tallies. In this scheme, the complete outgoing probability distribution is tallied, supplying every one of the scattering moment matrices elements with its share of data. In addition to reducing the uncertainty, this method allows for the use of a track-length estimation process potentially offering even further improvement to the tallying efficiency. Unfortunately, to produce the needed distributions, the probability functions themselves must undergo an integration over the outgoing energy and scattering angle dimensions. This integration is too costly to perform during the Monte Carlo simulation itself and therefore must be performed in advance by way of a pre-processing code. The new method increases the information obtained from tally events and therefore has a significantly higher efficiency than the currently used techniques. The improved method has been implemented in a code system containing a new pre-processor code, NDPP, and a Monte Carlo neutron transport code, OpenMC. This method is then tested in a pin cell problem and a larger problem designed to accentuate the importance of scattering moment matrices. These tests show that accuracy was retained while the figure-of-merit for generating scattering moment matrices and fission energy spectra was significantly improved.
Validation of Yoon's Critical Thinking Disposition Instrument.
Shin, Hyunsook; Park, Chang Gi; Kim, Hyojin
2015-12-01
The lack of reliable and valid evaluation tools targeting Korean nursing students' critical thinking (CT) abilities has been reported as one of the barriers to instructing and evaluating students in undergraduate programs. Yoon's Critical Thinking Disposition (YCTD) instrument was developed for Korean nursing students, but few studies have assessed its validity. This study aimed to validate the YCTD. Specifically, the YCTD was assessed to identify its cross-sectional and longitudinal measurement invariance. This was a validation study in which a cross-sectional and longitudinal (prenursing and postnursing practicum) survey was used to validate the YCTD using 345 nursing students at three universities in Seoul, Korea. The participants' CT abilities were assessed using the YCTD before and after completing an established pediatric nursing practicum. The validity of the YCTD was estimated and then group invariance test using multigroup confirmatory factor analysis was performed to confirm the measurement compatibility of multigroups. A test of the seven-factor model showed that the YCTD demonstrated good construct validity. Multigroup confirmatory factor analysis findings for the measurement invariance suggested that this model structure demonstrated strong invariance between groups (i.e., configural, factor loading, and intercept combined) but weak invariance within a group (i.e., configural and factor loading combined). In general, traditional methods for assessing instrument validity have been less than thorough. In this study, multigroup confirmatory factor analysis using cross-sectional and longitudinal measurement data allowed validation of the YCTD. This study concluded that the YCTD can be used for evaluating Korean nursing students' CT abilities. Copyright © 2015. Published by Elsevier B.V.
Methodes iteratives paralleles: Applications en neutronique et en mecanique des fluides
NASA Astrophysics Data System (ADS)
Qaddouri, Abdessamad
Dans cette these, le calcul parallele est applique successivement a la neutronique et a la mecanique des fluides. Dans chacune de ces deux applications, des methodes iteratives sont utilisees pour resoudre le systeme d'equations algebriques resultant de la discretisation des equations du probleme physique. Dans le probleme de neutronique, le calcul des matrices des probabilites de collision (PC) ainsi qu'un schema iteratif multigroupe utilisant une methode inverse de puissance sont parallelises. Dans le probleme de mecanique des fluides, un code d'elements finis utilisant un algorithme iteratif du type GMRES preconditionne est parallelise. Cette these est presentee sous forme de six articles suivis d'une conclusion. Les cinq premiers articles traitent des applications en neutronique, articles qui representent l'evolution de notre travail dans ce domaine. Cette evolution passe par un calcul parallele des matrices des PC et un algorithme multigroupe parallele teste sur un probleme unidimensionnel (article 1), puis par deux algorithmes paralleles l'un mutiregion l'autre multigroupe, testes sur des problemes bidimensionnels (articles 2--3). Ces deux premieres etapes sont suivies par l'application de deux techniques d'acceleration, le rebalancement neutronique et la minimisation du residu aux deux algorithmes paralleles (article 4). Finalement, on a mis en oeuvre l'algorithme multigroupe et le calcul parallele des matrices des PC sur un code de production DRAGON ou les tests sont plus realistes et peuvent etre tridimensionnels (article 5). Le sixieme article (article 6), consacre a l'application a la mecanique des fluides, traite la parallelisation d'un code d'elements finis FES ou le partitionneur de graphe METIS et la librairie PSPARSLIB sont utilises.
Ryu, Ehri; Cheong, Jeewon
2017-01-01
In this article, we evaluated the performance of statistical methods in single-group and multi-group analysis approaches for testing group difference in indirect effects and for testing simple indirect effects in each group. We also investigated whether the performance of the methods in the single-group approach was affected when the assumption of equal variance was not satisfied. The assumption was critical for the performance of the two methods in the single-group analysis: the method using a product term for testing the group difference in a single path coefficient, and the Wald test for testing the group difference in the indirect effect. Bootstrap confidence intervals in the single-group approach and all methods in the multi-group approach were not affected by the violation of the assumption. We compared the performance of the methods and provided recommendations. PMID:28553248
NASA-Lewis experiences with multigroup cross sections and shielding calculations
NASA Technical Reports Server (NTRS)
Lahti, G. P.
1972-01-01
The nuclear reactor shield analysis procedures employed at NASA-Lewis are described. Emphasis is placed on the generation, use, and testing of multigroup cross section data. Although coupled neutron and gamma ray cross section sets are useful in two dimensional Sn transport calculations, much insight has been gained from examination of uncoupled calculations. These have led to experimental and analytic studies of areas deemed to be of first order importance to reactor shield calculations. A discussion is given of problems encountered in using multigroup cross sections in the resolved resonance energy range. The addition to ENDF files of calculated and/or measured neutron-energy-dependent capture gamma ray spectra for shielding calculations is questioned for the resonance region. Anomalies inherent in two dimensional Sn transport calculations which may overwhelm any cross section discrepancies are illustrated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stimpson, Shane G.; Liu, Yuxuan; Collins, Benjamin S.
An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC) is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly 2×. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilitiesmore » have been demonstrated on two test cases: (1) a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications) Progression Problem 2a and (2) a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly 3–4×, with a corresponding 15–20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of 2×. In total, the improvements yield roughly a 7–8× speedup. Furthermore given these performance benefits, these approaches have been adopted as the default in MPACT.« less
Stimpson, Shane G.; Liu, Yuxuan; Collins, Benjamin S.; ...
2017-07-17
An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC) is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly 2×. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilitiesmore » have been demonstrated on two test cases: (1) a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications) Progression Problem 2a and (2) a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly 3–4×, with a corresponding 15–20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of 2×. In total, the improvements yield roughly a 7–8× speedup. Furthermore given these performance benefits, these approaches have been adopted as the default in MPACT.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Díez, C.J., E-mail: cj.diez@upm.es; Cabellos, O.; Instituto de Fusión Nuclear, Universidad Politécnica de Madrid, 28006 Madrid
Several approaches have been developed in last decades to tackle nuclear data uncertainty propagation problems of burn-up calculations. One approach proposed was the Hybrid Method, where uncertainties in nuclear data are propagated only on the depletion part of a burn-up problem. Because only depletion is addressed, only one-group cross sections are necessary, and hence, their collapsed one-group uncertainties. This approach has been applied successfully in several advanced reactor systems like EFIT (ADS-like reactor) or ESFR (Sodium fast reactor) to assess uncertainties on the isotopic composition. However, a comparison with using multi-group energy structures was not carried out, and has tomore » be performed in order to analyse the limitations of using one-group uncertainties.« less
NASA Astrophysics Data System (ADS)
Díez, C. J.; Cabellos, O.; Martínez, J. S.
2015-01-01
Several approaches have been developed in last decades to tackle nuclear data uncertainty propagation problems of burn-up calculations. One approach proposed was the Hybrid Method, where uncertainties in nuclear data are propagated only on the depletion part of a burn-up problem. Because only depletion is addressed, only one-group cross sections are necessary, and hence, their collapsed one-group uncertainties. This approach has been applied successfully in several advanced reactor systems like EFIT (ADS-like reactor) or ESFR (Sodium fast reactor) to assess uncertainties on the isotopic composition. However, a comparison with using multi-group energy structures was not carried out, and has to be performed in order to analyse the limitations of using one-group uncertainties.
Continuous-energy eigenvalue sensitivity coefficient calculations in TSUNAMI-3D
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perfetti, C. M.; Rearden, B. T.
2013-07-01
Two methods for calculating eigenvalue sensitivity coefficients in continuous-energy Monte Carlo applications were implemented in the KENO code within the SCALE code package. The methods were used to calculate sensitivity coefficients for several test problems and produced sensitivity coefficients that agreed well with both reference sensitivities and multigroup TSUNAMI-3D sensitivity coefficients. The newly developed CLUTCH method was observed to produce sensitivity coefficients with high figures of merit and a low memory footprint, and both continuous-energy sensitivity methods met or exceeded the accuracy of the multigroup TSUNAMI-3D calculations. (authors)
An improved random walk algorithm for the implicit Monte Carlo method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keady, Kendra P., E-mail: keadyk@lanl.gov; Cleveland, Mathew A.
In this work, we introduce a modified Implicit Monte Carlo (IMC) Random Walk (RW) algorithm, which increases simulation efficiency for multigroup radiative transfer problems with strongly frequency-dependent opacities. To date, the RW method has only been implemented in “fully-gray” form; that is, the multigroup IMC opacities are group-collapsed over the full frequency domain of the problem to obtain a gray diffusion problem for RW. This formulation works well for problems with large spatial cells and/or opacities that are weakly dependent on frequency; however, the efficiency of the RW method degrades when the spatial cells are thin or the opacities aremore » a strong function of frequency. To address this inefficiency, we introduce a RW frequency group cutoff in each spatial cell, which divides the frequency domain into optically thick and optically thin components. In the modified algorithm, opacities for the RW diffusion problem are obtained by group-collapsing IMC opacities below the frequency group cutoff. Particles with frequencies above the cutoff are transported via standard IMC, while particles below the cutoff are eligible for RW. This greatly increases the total number of RW steps taken per IMC time-step, which in turn improves the efficiency of the simulation. We refer to this new method as Partially-Gray Random Walk (PGRW). We present numerical results for several multigroup radiative transfer problems, which show that the PGRW method is significantly more efficient than standard RW for several problems of interest. In general, PGRW decreases runtimes by a factor of ∼2–4 compared to standard RW, and a factor of ∼3–6 compared to standard IMC. While PGRW is slower than frequency-dependent Discrete Diffusion Monte Carlo (DDMC), it is also easier to adapt to unstructured meshes and can be used in spatial cells where DDMC is not applicable. This suggests that it may be optimal to employ both DDMC and PGRW in a single simulation.« less
A new multigroup method for cross-sections that vary rapidly in energy
NASA Astrophysics Data System (ADS)
Haut, T. S.; Ahrens, C.; Jonko, A.; Lowrie, R.; Till, A.
2017-01-01
We present a numerical method for solving the time-independent thermal radiative transfer (TRT) equation or the neutron transport (NT) equation when the opacity (cross-section) varies rapidly in frequency (energy) on the microscale ε; ε corresponds to the characteristic spacing between absorption lines or resonances, and is much smaller than the macroscopic frequency (energy) variation of interest. The approach is based on a rigorous homogenization of the TRT/NT equation in the frequency (energy) variable. Discretization of the homogenized TRT/NT equation results in a multigroup-type system, and can therefore be solved by standard methods. We demonstrate the accuracy and efficiency of the approach on three model problems. First we consider the Elsasser band model with constant temperature and a line spacing ε =10-4 . Second, we consider a neutron transport application for fast neutrons incident on iron, where the characteristic resonance spacing ε necessitates ≈ 16 , 000 energy discretization parameters if Planck-weighted cross sections are used. Third, we consider an atmospheric TRT problem for an opacity corresponding to water vapor over a frequency range 1000-2000 cm-1, where we take 12 homogeneous layers between 1-15 km, and temperature/pressure values in each layer from the standard US atmosphere. For all three problems, we demonstrate that we can achieve between 0.1 and 1 percent relative error in the solution, and with several orders of magnitude fewer parameters than a standard multigroup formulation using Planck-weighted (source-weighted) opacities for a comparable accuracy.
ERIC Educational Resources Information Center
Gayles, Jochebed G.; Coatsworth, J. Douglas; Pantin, Hilda M.; Szapocznik, Jose
2009-01-01
This study examined the influence of family and neighborhood contexts on Hispanic youth problem behavior. The effects of parents' perceptions of neighborhood context and parenting practices on problem behavior were examined in 167 one-parent (n = 75) and two-parent (n = 92) families. Results from multigroup path analyses showed significant main…
A stable 1D multigroup high-order low-order method
Yee, Ben Chung; Wollaber, Allan Benton; Haut, Terry Scot; ...
2016-07-13
The high-order low-order (HOLO) method is a recently developed moment-based acceleration scheme for solving time-dependent thermal radiative transfer problems, and has been shown to exhibit orders of magnitude speedups over traditional time-stepping schemes. However, a linear stability analysis by Haut et al. (2015 Haut, T. S., Lowrie, R. B., Park, H., Rauenzahn, R. M., Wollaber, A. B. (2015). A linear stability analysis of the multigroup High-Order Low-Order (HOLO) method. In Proceedings of the Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method; Nashville, TN, April 19–23, 2015. American Nuclear Society.)more » revealed that the current formulation of the multigroup HOLO method was unstable in certain parameter regions. Since then, we have replaced the intensity-weighted opacity in the first angular moment equation of the low-order (LO) system with the Rosseland opacity. Furthermore, this results in a modified HOLO method (HOLO-R) that is significantly more stable.« less
Monte Carol-based validation of neutronic methodology for EBR-II analyses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liaw, J.R.; Finck, P.J.
1993-01-01
The continuous-energy Monte Carlo code VIM (Ref. 1) has been validated extensively over the years against fast critical experiments and other neutronic analysis codes. A high degree of confidence in VIM for predicting reactor physics parameters has been firmly established. This paper presents a numerical validation of two conventional multigroup neutronic analysis codes, DIF3D (Ref. 4) and VARIANT (Ref. 5), against VIM for two Experimental Breeder Reactor II (EBR-II) core loadings in detailed three-dimensional hexagonal-z geometry. The DIF3D code is based on nodal diffusion theory, and it is used in calculations for day-today reactor operations, whereas the VARIANT code ismore » based on nodal transport theory and is used with increasing frequency for specific applications. Both DIF3D and VARIANT rely on multigroup cross sections generated from ENDF/B-V by the ETOE-2/MC[sup 2]-II/SDX (Ref. 6) code package. Hence, this study also validates the multigroup cross-section processing methodology against the continuous-energy approach used in VIM.« less
The MCNP6 Analytic Criticality Benchmark Suite
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, Forrest B.
2016-06-16
Analytical benchmarks provide an invaluable tool for verifying computer codes used to simulate neutron transport. Several collections of analytical benchmark problems [1-4] are used routinely in the verification of production Monte Carlo codes such as MCNP® [5,6]. Verification of a computer code is a necessary prerequisite to the more complex validation process. The verification process confirms that a code performs its intended functions correctly. The validation process involves determining the absolute accuracy of code results vs. nature. In typical validations, results are computed for a set of benchmark experiments using a particular methodology (code, cross-section data with uncertainties, and modeling)more » and compared to the measured results from the set of benchmark experiments. The validation process determines bias, bias uncertainty, and possibly additional margins. Verification is generally performed by the code developers, while validation is generally performed by code users for a particular application space. The VERIFICATION_KEFF suite of criticality problems [1,2] was originally a set of 75 criticality problems found in the literature for which exact analytical solutions are available. Even though the spatial and energy detail is necessarily limited in analytical benchmarks, typically to a few regions or energy groups, the exact solutions obtained can be used to verify that the basic algorithms, mathematics, and methods used in complex production codes perform correctly. The present work has focused on revisiting this benchmark suite. A thorough review of the problems resulted in discarding some of them as not suitable for MCNP benchmarking. For the remaining problems, many of them were reformulated to permit execution in either multigroup mode or in the normal continuous-energy mode for MCNP. Execution of the benchmarks in continuous-energy mode provides a significant advance to MCNP verification methods.« less
Williams, M. L.; Wiarda, D.; Ilas, G.; ...
2014-06-15
Recently, we processed a new covariance data library based on ENDF/B-VII.1 for the SCALE nuclear analysis code system. The multigroup covariance data are discussed here, along with testing and application results for critical benchmark experiments. Moreover, the cross section covariance library, along with covariances for fission product yields and decay data, is used to compute uncertainties in the decay heat produced by a burned reactor fuel assembly.
A comparison of acceleration methods for solving the neutron transport k-eigenvalue problem
NASA Astrophysics Data System (ADS)
Willert, Jeffrey; Park, H.; Knoll, D. A.
2014-10-01
Over the past several years a number of papers have been written describing modern techniques for numerically computing the dominant eigenvalue of the neutron transport criticality problem. These methods fall into two distinct categories. The first category of methods rewrite the multi-group k-eigenvalue problem as a nonlinear system of equations and solve the resulting system using either a Jacobian-Free Newton-Krylov (JFNK) method or Nonlinear Krylov Acceleration (NKA), a variant of Anderson Acceleration. These methods are generally successful in significantly reducing the number of transport sweeps required to compute the dominant eigenvalue. The second category of methods utilize Moment-Based Acceleration (or High-Order/Low-Order (HOLO) Acceleration). These methods solve a sequence of modified diffusion eigenvalue problems whose solutions converge to the solution of the original transport eigenvalue problem. This second class of methods is, in our experience, always superior to the first, as most of the computational work is eliminated by the acceleration from the LO diffusion system. In this paper, we review each of these methods. Our computational results support our claim that the choice of which nonlinear solver to use, JFNK or NKA, should be secondary. The primary computational savings result from the implementation of a HOLO algorithm. We display computational results for a series of challenging multi-dimensional test problems.
MT71x: Multi-Temperature Library Based on ENDF/B-VII.1
DOE Office of Scientific and Technical Information (OSTI.GOV)
Conlin, Jeremy Lloyd; Parsons, Donald Kent; Gray, Mark Girard
The Nuclear Data Team has released a multitemperature transport library, MT71x, based upon ENDF/B-VII.1 with a few modifications as well as additional evaluations for a total of 427 isotope tables. The library was processed using NJOY2012.39 into 23 temperatures. MT71x consists of two sub-libraries; MT71xMG for multigroup energy representation data and MT71xCE for continuous energy representation data. These sub-libraries are suitable for deterministic transport and Monte Carlo transport applications, respectively. The SZAs used are the same for the two sub-libraries; that is, the same SZA can be used for both libraries. This makes comparisons between the two libraries and betweenmore » deterministic and Monte Carlo codes straightforward. Both the multigroup energy and continuous energy libraries were verified and validated with our checking codes checkmg and checkace (multigroup and continuous energy, respectively) Then an expanded suite of tests was used for additional verification and, finally, verified using an extensive suite of critical benchmark models. We feel that this library is suitable for all calculations and is particularly useful for calculations sensitive to temperature effects.« less
Parallel computation of multigroup reactivity coefficient using iterative method
NASA Astrophysics Data System (ADS)
Susmikanti, Mike; Dewayatna, Winter
2013-09-01
One of the research activities to support the commercial radioisotope production program is a safety research target irradiation FPM (Fission Product Molybdenum). FPM targets form a tube made of stainless steel in which the nuclear degrees of superimposed high-enriched uranium. FPM irradiation tube is intended to obtain fission. The fission material widely used in the form of kits in the world of nuclear medicine. Irradiation FPM tube reactor core would interfere with performance. One of the disorders comes from changes in flux or reactivity. It is necessary to study a method for calculating safety terrace ongoing configuration changes during the life of the reactor, making the code faster became an absolute necessity. Neutron safety margin for the research reactor can be reused without modification to the calculation of the reactivity of the reactor, so that is an advantage of using perturbation method. The criticality and flux in multigroup diffusion model was calculate at various irradiation positions in some uranium content. This model has a complex computation. Several parallel algorithms with iterative method have been developed for the sparse and big matrix solution. The Black-Red Gauss Seidel Iteration and the power iteration parallel method can be used to solve multigroup diffusion equation system and calculated the criticality and reactivity coeficient. This research was developed code for reactivity calculation which used one of safety analysis with parallel processing. It can be done more quickly and efficiently by utilizing the parallel processing in the multicore computer. This code was applied for the safety limits calculation of irradiated targets FPM with increment Uranium.
ERIC Educational Resources Information Center
Byrne, Barbara M.; van de Vijver, Fons J. R.
2010-01-01
A critical assumption in cross-cultural comparative research is that the instrument measures the same construct(s) in exactly the same way across all groups (i.e., the instrument is measurement and structurally equivalent). Structural equation modeling (SEM) procedures are commonly used in testing these assumptions of multigroup equivalence.…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hardy, J. Jr.
1977-12-01
Four H/sub 2/O-moderated, slightly-enriched-uranium critical experiments were analyzed by Monte Carlo methods with ENDF/B-IV data. These were simple metal-rod lattices comprising Cross Section Evaluation Working Group thermal reactor benchmarks TRX-1 through TRX-4. Generally good agreement with experiment was obtained for calculated integral parameters: the epi-thermal/thermal ratio of U238 capture (rho/sup 28/) and of U235 fission (delta/sup 25/), the ratio of U238 capture to U235 fission (CR*), and the ratio of U238 fission to U235 fission (delta/sup 28/). Full-core Monte Carlo calculations for two lattices showed good agreement with cell Monte Carlo-plus-multigroup P/sub l/ leakage corrections. Newly measured parameters for themore » low energy resonances of U238 significantly improved rho/sup 28/. In comparison with other CSEWG analyses, the strong correlation between K/sub eff/ and rho/sup 28/ suggests that U238 resonance capture is the major problem encountered in analyzing these lattices.« less
An Improved Neutron Transport Algorithm for Space Radiation
NASA Technical Reports Server (NTRS)
Heinbockel, John H.; Clowdsley, Martha S.; Wilson, John W.
2000-01-01
A low-energy neutron transport algorithm for use in space radiation protection is developed. The algorithm is based upon a multigroup analysis of the straight-ahead Boltzmann equation by using a mean value theorem for integrals. This analysis is accomplished by solving a realistic but simplified neutron transport test problem. The test problem is analyzed by using numerical and analytical procedures to obtain an accurate solution within specified error bounds. Results from the test problem are then used for determining mean values associated with rescattering terms that are associated with a multigroup solution of the straight-ahead Boltzmann equation. The algorithm is then coupled to the Langley HZETRN code through the evaporation source term. Evaluation of the neutron fluence generated by the solar particle event of February 23, 1956, for a water and an aluminum-water shield-target configuration is then compared with LAHET and MCNPX Monte Carlo code calculations for the same shield-target configuration. The algorithm developed showed a great improvement in results over the unmodified HZETRN solution. In addition, a two-directional solution of the evaporation source showed even further improvement of the fluence near the front of the water target where diffusion from the front surface is important.
NASA Astrophysics Data System (ADS)
Susmikanti, Mike; Dewayatna, Winter; Sulistyo, Yos
2014-09-01
One of the research activities in support of commercial radioisotope production program is a safety research on target FPM (Fission Product Molybdenum) irradiation. FPM targets form a tube made of stainless steel which contains nuclear-grade high-enrichment uranium. The FPM irradiation tube is intended to obtain fission products. Fission materials such as Mo99 used widely the form of kits in the medical world. The neutronics problem is solved using first-order perturbation theory derived from the diffusion equation for four groups. In contrast, Mo isotopes have longer half-lives, about 3 days (66 hours), so the delivery of radioisotopes to consumer centers and storage is possible though still limited. The production of this isotope potentially gives significant economic value. The criticality and flux in multigroup diffusion model was calculated for various irradiation positions and uranium contents. This model involves complex computation, with large and sparse matrix system. Several parallel algorithms have been developed for the sparse and large matrix solution. In this paper, a successive over-relaxation (SOR) algorithm was implemented for the calculation of reactivity coefficients which can be done in parallel. Previous works performed reactivity calculations serially with Gauss-Seidel iteratives. The parallel method can be used to solve multigroup diffusion equation system and calculate the criticality and reactivity coefficients. In this research a computer code was developed to exploit parallel processing to perform reactivity calculations which were to be used in safety analysis. The parallel processing in the multicore computer system allows the calculation to be performed more quickly. This code was applied for the safety limits calculation of irradiated FPM targets containing highly enriched uranium. The results of calculations neutron show that for uranium contents of 1.7676 g and 6.1866 g (× 106 cm-1) in a tube, their delta reactivities are the still within safety limits; however, for 7.9542 g and 8.838 g (× 106 cm-1) the limits were exceeded.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shemon, Emily R.; Smith, Micheal A.; Lee, Changho
2016-02-16
PROTEUS-SN is a three-dimensional, highly scalable, high-fidelity neutron transport code developed at Argonne National Laboratory. The code is applicable to all spectrum reactor transport calculations, particularly those in which a high degree of fidelity is needed either to represent spatial detail or to resolve solution gradients. PROTEUS-SN solves the second order formulation of the transport equation using the continuous Galerkin finite element method in space, the discrete ordinates approximation in angle, and the multigroup approximation in energy. PROTEUS-SN’s parallel methodology permits the efficient decomposition of the problem by both space and angle, permitting large problems to run efficiently on hundredsmore » of thousands of cores. PROTEUS-SN can also be used in serial or on smaller compute clusters (10’s to 100’s of cores) for smaller homogenized problems, although it is generally more computationally expensive than traditional homogenized methodology codes. PROTEUS-SN has been used to model partially homogenized systems, where regions of interest are represented explicitly and other regions are homogenized to reduce the problem size and required computational resources. PROTEUS-SN solves forward and adjoint eigenvalue problems and permits both neutron upscattering and downscattering. An adiabatic kinetics option has recently been included for performing simple time-dependent calculations in addition to standard steady state calculations. PROTEUS-SN handles void and reflective boundary conditions. Multigroup cross sections can be generated externally using the MC2-3 fast reactor multigroup cross section generation code or internally using the cross section application programming interface (API) which can treat the subgroup or resonance table libraries. PROTEUS-SN is written in Fortran 90 and also includes C preprocessor definitions. The code links against the PETSc, METIS, HDF5, and MPICH libraries. It optionally links against the MOAB library and is a part of the SHARP multi-physics suite for coupled multi-physics analysis of nuclear reactors. This user manual describes how to set up a neutron transport simulation with the PROTEUS-SN code. A companion methodology manual describes the theory and algorithms within PROTEUS-SN.« less
A multi-group firefly algorithm for numerical optimization
NASA Astrophysics Data System (ADS)
Tong, Nan; Fu, Qiang; Zhong, Caiming; Wang, Pengjun
2017-08-01
To solve the problem of premature convergence of firefly algorithm (FA), this paper analyzes the evolution mechanism of the algorithm, and proposes an improved Firefly algorithm based on modified evolution model and multi-group learning mechanism (IMGFA). A Firefly colony is divided into several subgroups with different model parameters. Within each subgroup, the optimal firefly is responsible for leading the others fireflies to implement the early global evolution, and establish the information mutual system among the fireflies. And then, each firefly achieves local search by following the brighter firefly in its neighbors. At the same time, learning mechanism among the best fireflies in various subgroups to exchange information can help the population to obtain global optimization goals more effectively. Experimental results verify the effectiveness of the proposed algorithm.
ERIC Educational Resources Information Center
Macek, Victor C.
The nine Reactor Statics Modules are designed to introduce students to the use of numerical methods and digital computers for calculation of neutron flux distributions in space and energy which are needed to calculate criticality, power distribution, and fuel burnup for both slow neutron and fast neutron fission reactors. The last module, RS-9,…
AMPX: a modular code system for generating coupled multigroup neutron-gamma libraries from ENDF/B
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greene, N.M.; Lucius, J.L.; Petrie, L.M.
1976-03-01
AMPX is a modular system for producing coupled multigroup neutron-gamma cross section sets. Basic neutron and gamma cross-section data for AMPX are obtained from ENDF/B libraries. Most commonly used operations required to generate and collapse multigroup cross-section sets are provided in the system. AMPX is flexibly dimensioned; neutron group structures, and gamma group structures, and expansion orders to represent anisotropic processes are all arbitrary and limited only by available computer core and budget. The basic processes provided will (1) generate multigroup neutron cross sections; (2) generate multigroup gamma cross sections; (3) generate gamma yields for gamma-producing neutron interactions; (4) combinemore » neutron cross sections, gamma cross sections, and gamma yields into final ''coupled sets''; (5) perform one-dimensional discrete ordinates transport or diffusion theory calculations for neutrons and gammas and, on option, collapse the cross sections to a broad-group structure, using the one-dimensional results as weighting functions; (6) plot cross sections, on option, to facilitate the ''evaluation'' of a particular multigroup set of data; (7) update and maintain multigroup cross section libraries in such a manner as to make it not only easy to combine new data with previously processed data but also to do it in a single pass on the computer; and (8) output multigroup cross sections in convenient formats for other codes. (auth)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Burns, Kimberly A.
2009-08-01
The accurate and efficient simulation of coupled neutron-photon problems is necessary for several important radiation detection applications. Examples include the detection of nuclear threats concealed in cargo containers and prompt gamma neutron activation analysis for nondestructive determination of elemental composition of unknown samples.
ERIC Educational Resources Information Center
Hartley, Michael T.
2012-01-01
This study examined the assessment of resilience in undergraduate college students. Multigroup comparisons of the Connor-Davidson Resilience Scale (CD-RISC; Connor & Davidson, 2003) were performed on general population students and students recruited from campus mental health offices offering college counseling, psychiatric-support, and…
Multigroup Radiation-Hydrodynamics with a High-Order, Low-Order Method
Wollaber, Allan Benton; Park, HyeongKae; Lowrie, Robert Byron; ...
2016-12-09
Recent efforts at Los Alamos National Laboratory to develop a moment-based, scale-bridging [or high-order (HO)–low-order (LO)] algorithm for solving large varieties of the transport (kinetic) systems have shown promising results. A part of our ongoing effort is incorporating this methodology into the framework of the Eulerian Applications Project to achieve algorithmic acceleration of radiationhydrodynamics simulations in production software. By starting from the thermal radiative transfer equations with a simple material-motion correction, we derive a discretely consistent energy balance equation (LO equation). We demonstrate that the corresponding LO system for the Monte Carlo HO solver is closely related to the originalmore » LO system without material-motion corrections. We test the implementation on a radiative shock problem and show consistency between the energy densities and temperatures in the HO and LO solutions as well as agreement with the semianalytic solution. We also test the approach on a more challenging two-dimensional problem and demonstrate accuracy enhancements and algorithmic speedups. This paper extends a recent conference paper by including multigroup effects.« less
Tein, Jenn-Yun; Mazza, Gina L; Gunn, Heather J; Kim, Hanjoe; Stuart, Elizabeth A; Sandler, Irwin N; Wolchik, Sharlene A
2018-06-01
We used a multigroup propensity score approach to evaluate a randomized effectiveness trial of the New Beginnings Program (NBP), an intervention targeting divorced or separated families. Two features of effectiveness trials, high nonattendance rates and inclusion of an active control, make program effects harder to detect. To estimate program effects based on actual intervention participation, we created a synthetic inactive control comprised of nonattenders and assessed the impact of attending the NBP or active control relative to no intervention (inactive control). We estimated propensity scores using generalized boosted models and applied inverse probability of treatment weighting for the comparisons. Relative to the inactive control, NBP strengthened parenting quality as well as reduced child exposure to interparental conflict, parent psychological distress, and child internalizing problems. Some effects were moderated by parent gender, parent ethnicity, or child age. On the other hand, the effects of active versus inactive control were minimal for parenting and in the unexpected direction for child internalizing problems. Findings from the propensity score approach complement and enhance the interpretation of findings from the intention-to-treat approach.
Nuclear data uncertainty propagation by the XSUSA method in the HELIOS2 lattice code
NASA Astrophysics Data System (ADS)
Wemple, Charles; Zwermann, Winfried
2017-09-01
Uncertainty quantification has been extensively applied to nuclear criticality analyses for many years and has recently begun to be applied to depletion calculations. However, regulatory bodies worldwide are trending toward requiring such analyses for reactor fuel cycle calculations, which also requires uncertainty propagation for isotopics and nuclear reaction rates. XSUSA is a proven methodology for cross section uncertainty propagation based on random sampling of the nuclear data according to covariance data in multi-group representation; HELIOS2 is a lattice code widely used for commercial and research reactor fuel cycle calculations. This work describes a technique to automatically propagate the nuclear data uncertainties via the XSUSA approach through fuel lattice calculations in HELIOS2. Application of the XSUSA methodology in HELIOS2 presented some unusual challenges because of the highly-processed multi-group cross section data used in commercial lattice codes. Currently, uncertainties based on the SCALE 6.1 covariance data file are being used, but the implementation can be adapted to other covariance data in multi-group structure. Pin-cell and assembly depletion calculations, based on models described in the UAM-LWR Phase I and II benchmarks, are performed and uncertainties in multiplication factor, reaction rates, isotope concentrations, and delayed-neutron data are calculated. With this extension, it will be possible for HELIOS2 users to propagate nuclear data uncertainties directly from the microscopic cross sections to subsequent core simulations.
Importance of resonance interference effects in multigroup self-shielding calculation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stachowski, R.E.; Protsik, R.
1995-12-31
The impact of the resonance interference method (RIF) on multigroup neutron cross sections is significant for major isotopes in the fuel, indicating the importance of resonance interference in the computation of gadolinia burnout and plutonium buildup. The self-shielding factor method with the RIF method effectively eliminates shortcomings in multigroup resonance calculations.
Resonance treatment using pin-based pointwise energy slowing-down method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi, Sooyoung, E-mail: csy0321@unist.ac.kr; Lee, Changho, E-mail: clee@anl.gov; Lee, Deokjung, E-mail: deokjung@unist.ac.kr
A new resonance self-shielding method using a pointwise energy solution has been developed to overcome the drawbacks of the equivalence theory. The equivalence theory uses a crude resonance scattering source approximation, and assumes a spatially constant scattering source distribution inside a fuel pellet. These two assumptions cause a significant error, in that they overestimate the multi-group effective cross sections, especially for {sup 238}U. The new resonance self-shielding method solves pointwise energy slowing-down equations with a sub-divided fuel rod. The method adopts a shadowing effect correction factor and fictitious moderator material to model a realistic pointwise energy solution. The slowing-down solutionmore » is used to generate the multi-group cross section. With various light water reactor problems, it was demonstrated that the new resonance self-shielding method significantly improved accuracy in the reactor parameter calculation with no compromise in computation time, compared to the equivalence theory.« less
Procedure to Generate the MPACT Multigroup Library
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Kang Seog
The CASL neutronics simulator MPACT is under development for the neutronics and T-H coupled simulation for the light water reactor. The objective of this document is focused on reviewing the current procedure to generate the MPACT multigroup library. Detailed methodologies and procedures are included in this document for further discussion to improve the MPACT multigroup library.
Encoded physics knowledge in checking codes for nuclear cross section libraries at Los Alamos
NASA Astrophysics Data System (ADS)
Parsons, D. Kent
2017-09-01
Checking procedures for processed nuclear data at Los Alamos are described. Both continuous energy and multi-group nuclear data are verified by locally developed checking codes which use basic physics knowledge and common-sense rules. A list of nuclear data problems which have been identified with help of these checking codes is also given.
ERIC Educational Resources Information Center
Dembo, Richard; M. Krupa, Julie; Wareham, Jennifer; Schmeidler, James; DiClemente, Ralph J.
2017-01-01
Truant youths are likely to engage in a number of problem behaviors, including sexual risky behaviors. Previous research involving non-truant youths has found sexual risk behaviors to be related to marijuana use and depression, with differential effects for male and female youths. Using data collected in a National Institute on Drug Abuse…
VENTURE/PC manual: A multidimensional multigroup neutron diffusion code system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shapiro, A.; Huria, H.C.; Cho, K.W.
1991-12-01
VENTURE/PC is a recompilation of part of the Oak Ridge BOLD VENTURE code system, which will operate on an IBM PC or compatible computer. Neutron diffusion theory solutions are obtained for multidimensional, multigroup problems. This manual contains information associated with operating the code system. The purpose of the various modules used in the code system, and the input for these modules are discussed. The PC code structure is also given. Version 2 included several enhancements not given in the original version of the code. In particular, flux iterations can be done in core rather than by reading and writing tomore » disk, for problems which allow sufficient memory for such in-core iterations. This speeds up the iteration process. Version 3 does not include any of the special processors used in the previous versions. These special processors utilized formatted input for various elements of the code system. All such input data is now entered through the Input Processor, which produces standard interface files for the various modules in the code system. In addition, a Standard Interface File Handbook is included in the documentation which is distributed with the code, to assist in developing the input for the Input Processor.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swesty, F. Douglas; Myra, Eric S.
It is now generally agreed that multidimensional, multigroup, neutrino-radiation hydrodynamics (RHD) is an indispensable element of any realistic model of stellar-core collapse, core-collapse supernovae, and proto-neutron star instabilities. We have developed a new, two-dimensional, multigroup algorithm that can model neutrino-RHD flows in core-collapse supernovae. Our algorithm uses an approach similar to the ZEUS family of algorithms, originally developed by Stone and Norman. However, this completely new implementation extends that previous work in three significant ways: first, we incorporate multispecies, multigroup RHD in a flux-limited-diffusion approximation. Our approach is capable of modeling pair-coupled neutrino-RHD, and includes effects of Pauli blocking inmore » the collision integrals. Blocking gives rise to nonlinearities in the discretized radiation-transport equations, which we evolve implicitly in time. We employ parallelized Newton-Krylov methods to obtain a solution of these nonlinear, implicit equations. Our second major extension to the ZEUS algorithm is the inclusion of an electron conservation equation that describes the evolution of electron-number density in the hydrodynamic flow. This permits calculating deleptonization of a stellar core. Our third extension modifies the hydrodynamics algorithm to accommodate realistic, complex equations of state, including those having nonconvex behavior. In this paper, we present a description of our complete algorithm, giving sufficient details to allow others to implement, reproduce, and extend our work. Finite-differencing details are presented in appendices. We also discuss implementation of this algorithm on state-of-the-art, parallel-computing architectures. Finally, we present results of verification tests that demonstrate the numerical accuracy of this algorithm on diverse hydrodynamic, gravitational, radiation-transport, and RHD sample problems. We believe our methods to be of general use in a variety of model settings where radiation transport or RHD is important. Extension of this work to three spatial dimensions is straightforward.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yee, Ben Chung; Wollaber, Allan Benton; Haut, Terry Scot
The high-order low-order (HOLO) method is a recently developed moment-based acceleration scheme for solving time-dependent thermal radiative transfer problems, and has been shown to exhibit orders of magnitude speedups over traditional time-stepping schemes. However, a linear stability analysis by Haut et al. (2015 Haut, T. S., Lowrie, R. B., Park, H., Rauenzahn, R. M., Wollaber, A. B. (2015). A linear stability analysis of the multigroup High-Order Low-Order (HOLO) method. In Proceedings of the Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo (MC) Method; Nashville, TN, April 19–23, 2015. American Nuclear Society.)more » revealed that the current formulation of the multigroup HOLO method was unstable in certain parameter regions. Since then, we have replaced the intensity-weighted opacity in the first angular moment equation of the low-order (LO) system with the Rosseland opacity. Furthermore, this results in a modified HOLO method (HOLO-R) that is significantly more stable.« less
Multi-group Fokker-Planck proton transport in MCNP{trademark}
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adams, K.J.
1997-11-01
MCNP has been enhanced to perform proton transport using a multigroup Fokker Planck (MGFP) algorithm with primary emphasis on proton radiography simulations. The new method solves the Fokker Planck approximation to the Boltzmann transport equation for the small angle multiple scattering portion of proton transport. Energy loss is accounted for by applying a group averaged stopping power over each transport step. Large angle scatter and non-inelastic events are treated as extinction. Comparisons with the more rigorous LAHET code show agreement to a few per cent for the total transmitted currents. The angular distributions through copper and low Z compounds showmore » good agreement between LAHET and MGFP with the MGFP method being slightly less forward peaked and without the large angle tails apparent in the LAHET simulation. Suitability of this method for proton radiography simulations is shown for a simple problem of a hole in a copper slab. LAHET and MGFP calculations of position, angle and energy through more complex objects are presented.« less
VENTURE/PC manual: A multidimensional multigroup neutron diffusion code system. Version 3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shapiro, A.; Huria, H.C.; Cho, K.W.
1991-12-01
VENTURE/PC is a recompilation of part of the Oak Ridge BOLD VENTURE code system, which will operate on an IBM PC or compatible computer. Neutron diffusion theory solutions are obtained for multidimensional, multigroup problems. This manual contains information associated with operating the code system. The purpose of the various modules used in the code system, and the input for these modules are discussed. The PC code structure is also given. Version 2 included several enhancements not given in the original version of the code. In particular, flux iterations can be done in core rather than by reading and writing tomore » disk, for problems which allow sufficient memory for such in-core iterations. This speeds up the iteration process. Version 3 does not include any of the special processors used in the previous versions. These special processors utilized formatted input for various elements of the code system. All such input data is now entered through the Input Processor, which produces standard interface files for the various modules in the code system. In addition, a Standard Interface File Handbook is included in the documentation which is distributed with the code, to assist in developing the input for the Input Processor.« less
New Tools to Prepare ACE Cross-section Files for MCNP Analytic Test Problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brown, Forrest B.
Monte Carlo calculations using one-group cross sections, multigroup cross sections, or simple continuous energy cross sections are often used to: (1) verify production codes against known analytical solutions, (2) verify new methods and algorithms that do not involve detailed collision physics, (3) compare Monte Carlo calculation methods with deterministic methods, and (4) teach fundamentals to students. In this work we describe 2 new tools for preparing the ACE cross-section files to be used by MCNP ® for these analytic test problems, simple_ace.pl and simple_ace_mg.pl.
DOE Office of Scientific and Technical Information (OSTI.GOV)
2015-10-19
CEPXS is a multigroup-Legendre cross-section generating code. The cross sections produced by CEPXS enable coupled electron-photon transport calculations to be performed with multigroup radiation transport codes, e.g. MITS and SCEPTRE. CEPXS generates multigroup-Legendre cross sections for photons, electrons and positrons over the energy range from 100 MeV to 1.0 keV. The continuous slowing-down approximation is used for those electron interactions that result in small-energy losses. The extended transport correction is applied to the forward-peaked elastic scattering cross section for electrons. A standard multigroup-Legendre treatment is used for the other coupled electron-photon cross sections. CEPXS extracts electron cross-section information from themore » DATAPAC data set and photon cross-section information from Biggs-Lighthill data. The model that is used for ionization/relaxation in CEPXS is essentially the same as that employed in ITS.« less
Cantisano, Gabriela Topa; Domínguez, J Francisco Morales; García, J Luis Caeiro
2007-05-01
This study focuses on the mediator role of social comparison in the relationship between perceived breach of psychological contract and burnout. A previous model showing the hypothesized effects of perceived breach on burnout, both direct and mediated, is proposed. The final model reached an optimal fit to the data and was confirmed through multigroup analysis using a sample of Spanish teachers (N = 401) belonging to preprimary, primary, and secondary schools. Multigroup analyses showed that the model fit all groups adequately.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rearden, Bradley T.; Jessee, Matthew Anderson
The SCALE Code System is a widely-used modeling and simulation suite for nuclear safety analysis and design that is developed, maintained, tested, and managed by the Reactor and Nuclear Systems Division (RNSD) of Oak Ridge National Laboratory (ORNL). SCALE provides a comprehensive, verified and validated, user-friendly tool set for criticality safety, reactor and lattice physics, radiation shielding, spent fuel and radioactive source term characterization, and sensitivity and uncertainty analysis. Since 1980, regulators, licensees, and research institutions around the world have used SCALE for safety analysis and design. SCALE provides an integrated framework with dozens of computational modules including three deterministicmore » and three Monte Carlo radiation transport solvers that are selected based on the desired solution strategy. SCALE includes current nuclear data libraries and problem-dependent processing tools for continuous-energy (CE) and multigroup (MG) neutronics and coupled neutron-gamma calculations, as well as activation, depletion, and decay calculations. SCALE includes unique capabilities for automated variance reduction for shielding calculations, as well as sensitivity and uncertainty analysis. SCALE’s graphical user interfaces assist with accurate system modeling, visualization of nuclear data, and convenient access to desired results.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rearden, Bradley T.; Jessee, Matthew Anderson
The SCALE Code System is a widely-used modeling and simulation suite for nuclear safety analysis and design that is developed, maintained, tested, and managed by the Reactor and Nuclear Systems Division (RNSD) of Oak Ridge National Laboratory (ORNL). SCALE provides a comprehensive, verified and validated, user-friendly tool set for criticality safety, reactor and lattice physics, radiation shielding, spent fuel and radioactive source term characterization, and sensitivity and uncertainty analysis. Since 1980, regulators, licensees, and research institutions around the world have used SCALE for safety analysis and design. SCALE provides an integrated framework with dozens of computational modules including three deterministicmore » and three Monte Carlo radiation transport solvers that are selected based on the desired solution strategy. SCALE includes current nuclear data libraries and problem-dependent processing tools for continuous-energy (CE) and multigroup (MG) neutronics and coupled neutron-gamma calculations, as well as activation, depletion, and decay calculations. SCALE includes unique capabilities for automated variance reduction for shielding calculations, as well as sensitivity and uncertainty analysis. SCALE’s graphical user interfaces assist with accurate system modeling, visualization of nuclear data, and convenient access to desired results.« less
Local Multi-Grouped Binary Descriptor With Ring-Based Pooling Configuration and Optimization.
Gao, Yongqiang; Huang, Weilin; Qiao, Yu
2015-12-01
Local binary descriptors are attracting increasingly attention due to their great advantages in computational speed, which are able to achieve real-time performance in numerous image/vision applications. Various methods have been proposed to learn data-dependent binary descriptors. However, most existing binary descriptors aim overly at computational simplicity at the expense of significant information loss which causes ambiguity in similarity measure using Hamming distance. In this paper, by considering multiple features might share complementary information, we present a novel local binary descriptor, referred as ring-based multi-grouped descriptor (RMGD), to successfully bridge the performance gap between current binary and floated-point descriptors. Our contributions are twofold. First, we introduce a new pooling configuration based on spatial ring-region sampling, allowing for involving binary tests on the full set of pairwise regions with different shapes, scales, and distances. This leads to a more meaningful description than the existing methods which normally apply a limited set of pooling configurations. Then, an extended Adaboost is proposed for an efficient bit selection by emphasizing high variance and low correlation, achieving a highly compact representation. Second, the RMGD is computed from multiple image properties where binary strings are extracted. We cast multi-grouped features integration as rankSVM or sparse support vector machine learning problem, so that different features can compensate strongly for each other, which is the key to discriminativeness and robustness. The performance of the RMGD was evaluated on a number of publicly available benchmarks, where the RMGD outperforms the state-of-the-art binary descriptors significantly.
Tiggelman, Dana; van de Ven, Monique O M; van Schayck, Onno C P; Engels, Rutger C M E
2014-12-01
Adolescents with asthma experience more psychosocial and physiological problems compared to their healthy peers. Physical activity (PA) might decrease these problems. This study was the first observational longitudinal study to examine whether habitual PA could predict changes in psychosocial outcomes (i.e., symptoms of anxiety and depression, quality of life [QOL] and stress) and asthma control over time in adolescents with asthma and whether gender moderated these relationships. Adolescents with asthma (N = 253; aged 10-14 years at baseline) were visited at home in the spring/summer of 2012 and 2013. They completed questionnaires assessing their habitual PA, symptoms of anxiety and depression, QOL, perceived stress and asthma control. Path analyses using Mplus were conducted to examine longitudinal relationships among habitual PA, psychosocial outcomes and asthma control (controlled for body mass index, age and gender). Using multi-group analyses, we examined whether gender moderated these relationships. Path analyses in the total group showed that habitual PA did not predict changes in psychosocial outcomes or asthma control over time. Multi-group analyses showed that gender moderated the relation of habitual PA with anxiety and depression. Habitual PA only significantly predicted a decrease in anxiety and depression over time for girls but not for boys. Increasing habitual PA in girls with asthma might decrease their symptoms of anxiety and depression.
Weiss, Nicole H.; Johnson, Clinesha D.; Contractor, Ateka; Peasant, Courtney; Swan, Suzanne C.; Sullivan, Tami P.
2017-01-01
Background Past research underscores the key role of coping strategies in the development, maintenance, and exacerbation of posttraumatic stress disorder (PTSD) symptoms. The goal of the current study was to extend existing literature by examining whether race/ethnicity moderates the relations among coping strategies (social support, problem-solving, avoidance) and PTSD symptom clusters (intrusion, avoidance, numbing, arousal). Methods Participants were 369 community women (134 African Americans, 131 Latinas, 104 Whites) who reported bidirectional aggression with a current male partner. Multigroup path analysis was utilized to test the moderating role of race/ethnicity in a model linking coping strategies to PTSD symptom clusters. Results The strength and direction of relations among coping strategies and PTSD symptom clusters varied as a function of race/ethnicity. Greater social support coping was related to more arousal symptoms for Latinas and Whites. Greater problem-solving coping was related to fewer arousal symptoms for Latinas. Greater avoidance coping was related to more symptoms across many of the PTSD clusters for African Americans, Latinas, and Whites, however, these relations were strongest for African Americans. Conclusion Results provide support for the moderating role of race/ethnicity in the relations among coping strategies and PTSD symptom clusters, and highlight potential targets for culturally-informed PTSD treatments. PMID:27575609
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gibson, N. A.; Forget, B.
2012-07-01
The Discrete Generalized Multigroup (DGM) method uses discrete Legendre orthogonal polynomials to expand the energy dependence of the multigroup neutron transport equation. This allows a solution on a fine energy mesh to be approximated for a cost comparable to a solution on a coarse energy mesh. The DGM method is applied to an ultra-fine energy mesh (14,767 groups) to avoid using self-shielding methodologies without introducing the cost usually associated with such energy discretization. Results show DGM to converge to the reference ultra-fine solution after a small number of recondensation steps for multiple infinite medium compositions. (authors)
NASA Technical Reports Server (NTRS)
Stamnes, K.; Lie-Svendsen, O.; Rees, M. H.
1991-01-01
The linear Boltzmann equation can be cast in a form mathematically identical to the radiation-transport equation. A multigroup procedure is used to reduce the energy (or velocity) dependence of the transport equation to a series of one-speed problems. Each of these one-speed problems is equivalent to the monochromatic radiative-transfer problem, and existing software is used to solve this problem in slab geometry. The numerical code conserves particles in elastic collisions. Generic examples are provided to illustrate the applicability of this approach. Although this formalism can, in principle, be applied to a variety of test particle or linearized gas dynamics problems, it is particularly well-suited to study the thermalization of suprathermal particles interacting with a background medium when the thermal motion of the background cannot be ignored. Extensions of the formalism to include external forces and spherical geometry are also feasible.
Construction, classification and parametrization of complex Hadamard matrices
NASA Astrophysics Data System (ADS)
Szöllősi, Ferenc
To improve the design of nuclear systems, high-fidelity neutron fluxes are required. Leadership-class machines provide platforms on which very large problems can be solved. Computing such fluxes efficiently requires numerical methods with good convergence properties and algorithms that can scale to hundreds of thousands of cores. Many 3-D deterministic transport codes are decomposable in space and angle only, limiting them to tens of thousands of cores. Most codes rely on methods such as Gauss Seidel for fixed source problems and power iteration for eigenvalue problems, which can be slow to converge for challenging problems like those with highly scattering materials or high dominance ratios. Three methods have been added to the 3-D SN transport code Denovo that are designed to improve convergence and enable the full use of cutting-edge computers. The first is a multigroup Krylov solver that converges more quickly than Gauss Seidel and parallelizes the code in energy such that Denovo can use hundreds of thousand of cores effectively. The second is Rayleigh quotient iteration (RQI), an old method applied in a new context. This eigenvalue solver finds the dominant eigenvalue in a mathematically optimal way and should converge in fewer iterations than power iteration. RQI creates energy-block-dense equations that the new Krylov solver treats efficiently. However, RQI can have convergence problems because it creates poorly conditioned systems. This can be overcome with preconditioning. The third method is a multigrid-in-energy preconditioner. The preconditioner takes advantage of the new energy decomposition because the grids are in energy rather than space or angle. The preconditioner greatly reduces iteration count for many problem types and scales well in energy. It also allows RQI to be successful for problems it could not solve otherwise. The methods added to Denovo accomplish the goals of this work. They converge in fewer iterations than traditional methods and enable the use of hundreds of thousands of cores. Each method can be used individually, with the multigroup Krylov solver and multigrid-in-energy preconditioner being particularly successful on their own. The largest benefit, though, comes from using these methods in concert.
ERIC Educational Resources Information Center
Dolan, Conor V.; Molenaar, Peter C. M.
1994-01-01
In multigroup covariance structure analysis with structured means, the traditional latent selection model is formulated as a special case of phenotypic selection. Illustrations with real and simulated data demonstrate how one can test specific hypotheses concerning selection on latent variables. (SLD)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nakhai, B.
A new method for solving radiation transport problems is presented. The heart of the technique is a new cross section processing procedure for the calculation of group-to-point and point-to-group cross sections sets. The method is ideally suited for problems which involve media with highly fluctuating cross sections, where the results of the traditional multigroup calculations are beclouded by the group averaging procedures employed. Extensive computational efforts, which would be required to evaluate double integrals in the multigroup treatment numerically, prohibit iteration to optimize the energy boundaries. On the other hand, use of point-to-point techniques (as in the stochastic technique) ismore » often prohibitively expensive due to the large computer storage requirement. The pseudo-point code is a hybrid of the two aforementioned methods (group-to-group and point-to-point) - hence the name pseudo-point - that reduces the computational efforts of the former and the large core requirements of the latter. The pseudo-point code generates the group-to-point or the point-to-group transfer matrices, and can be coupled with the existing transport codes to calculate pointwise energy-dependent fluxes. This approach yields much more detail than is available from the conventional energy-group treatments. Due to the speed of this code, several iterations could be performed (in affordable computing efforts) to optimize the energy boundaries and the weighting functions. The pseudo-point technique is demonstrated by solving six problems, each depicting a certain aspect of the technique. The results are presented as flux vs energy at various spatial intervals. The sensitivity of the technique to the energy grid and the savings in computational effort are clearly demonstrated.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghrayeb, S. Z.; Ouisloumen, M.; Ougouag, A. M.
2012-07-01
A multi-group formulation for the exact neutron elastic scattering kernel is developed. This formulation is intended for implementation into a lattice physics code. The correct accounting for the crystal lattice effects influences the estimated values for the probability of neutron absorption and scattering, which in turn affect the estimation of core reactivity and burnup characteristics. A computer program has been written to test the formulation for various nuclides. Results of the multi-group code have been verified against the correct analytic scattering kernel. In both cases neutrons were started at various energies and temperatures and the corresponding scattering kernels were tallied.more » (authors)« less
Familial Correlates of Overt and Relational Aggression between Young Adolescent Siblings
ERIC Educational Resources Information Center
Yu, Jeong Jin; Gamble, Wendy C.
2008-01-01
Multi-group confirmatory factor analysis and multi-group structural equation modeling were used to test correlates of overt and relational aggression between young adolescent siblings across four groups (i.e., male/male, male/female, female/male, and female/female sibling pairs), using 433 predominately European American families. Similar patterns…
Testing Measurement Invariance in the Target Rotated Multigroup Exploratory Factor Model
ERIC Educational Resources Information Center
Dolan, Conor V.; Oort, Frans J.; Stoel, Reinoud D.; Wicherts, Jelte M.
2009-01-01
We propose a method to investigate measurement invariance in the multigroup exploratory factor model, subject to target rotation. We consider both oblique and orthogonal target rotation. This method has clear advantages over other approaches, such as the use of congruence measures. We demonstrate that the model can be implemented readily in the…
Herrera-López, Mauricio; Casas, José A; Romera, Eva M; Ortega-Ruiz, Rosario; Del Rey, Rosario
2017-02-01
Cyberbullying is the act of using unjustified aggression to harm or harass via digital devices. Currently regarded as a widespread problem, the phenomenon has attracted growing research interest in different measures of cyberbullying and the similarities and differences across countries and cultures. This article presents the Colombian validation of the European Cyberbullying Intervention Project Questionnaire (ECIPQ) involving 3,830 high school students (M = 13.9 years old, standard deviation = 1.61; 48.9 percent male), of which 1,931 were Colombian and 1,899 Spanish. Confirmatory factor analysis (CFA), content validation, and multigroup analysis were performed with each of the sample subgroups. The optimal fits and psychometric properties obtained confirm the robustness and suitability of the assessment instrument to jointly measure cyber-aggression and cyber-victimization. The results corroborated the theoretical construct and the two-dimensional and universal nature of cyberbullying. The multigroup analysis showed that cyberbullying dynamics are similar in both countries. The comparative analyses of prevalence revealed that Colombian students are less involved in cyberbullying. The results indicate the suitability of the instrument and the advantages of using such a tool to evaluate and guide psychoeducational interventions aimed at preventing cyberbullying in countries where few studies have been performed.
Using kaizen to improve employee well-being: Results from two organizational intervention studies.
von Thiele Schwarz, Ulrica; Nielsen, Karina M; Stenfors-Hayes, Terese; Hasson, Henna
2017-08-01
Participatory intervention approaches that are embedded in existing organizational structures may improve the efficiency and effectiveness of organizational interventions, but concrete tools are lacking. In the present article, we use a realist evaluation approach to explore the role of kaizen, a lean tool for participatory continuous improvement, in improving employee well-being in two cluster-randomized, controlled participatory intervention studies. Case 1 is from the Danish Postal Service, where kaizen boards were used to implement action plans. The results of multi-group structural equation modeling showed that kaizen served as a mechanism that increased the level of awareness of and capacity to manage psychosocial issues, which, in turn, predicted increased job satisfaction and mental health. Case 2 is from a regional hospital in Sweden that integrated occupational health processes with a pre-existing kaizen system. Multi-group structural equation modeling revealed that, in the intervention group, kaizen work predicted better integration of organizational and employee objectives after 12 months, which, in turn, predicted increased job satisfaction and decreased discomfort at 24 months. The findings suggest that participatory and structured problem-solving approaches that are familiar and visual to employees can facilitate organizational interventions.
Using kaizen to improve employee well-being: Results from two organizational intervention studies
von Thiele Schwarz, Ulrica; Nielsen, Karina M; Stenfors-Hayes, Terese; Hasson, Henna
2016-01-01
Participatory intervention approaches that are embedded in existing organizational structures may improve the efficiency and effectiveness of organizational interventions, but concrete tools are lacking. In the present article, we use a realist evaluation approach to explore the role of kaizen, a lean tool for participatory continuous improvement, in improving employee well-being in two cluster-randomized, controlled participatory intervention studies. Case 1 is from the Danish Postal Service, where kaizen boards were used to implement action plans. The results of multi-group structural equation modeling showed that kaizen served as a mechanism that increased the level of awareness of and capacity to manage psychosocial issues, which, in turn, predicted increased job satisfaction and mental health. Case 2 is from a regional hospital in Sweden that integrated occupational health processes with a pre-existing kaizen system. Multi-group structural equation modeling revealed that, in the intervention group, kaizen work predicted better integration of organizational and employee objectives after 12 months, which, in turn, predicted increased job satisfaction and decreased discomfort at 24 months. The findings suggest that participatory and structured problem-solving approaches that are familiar and visual to employees can facilitate organizational interventions. PMID:28736455
Testing for Two-Way Interactions in the Multigroup Common Factor Model
ERIC Educational Resources Information Center
van Smeden, Maarten; Hessen, David J.
2013-01-01
In this article, a 2-way multigroup common factor model (MG-CFM) is presented. The MG-CFM can be used to estimate interaction effects between 2 grouping variables on 1 or more hypothesized latent variables. For testing the significance of such interactions, a likelihood ratio test is presented. In a simulation study, the robustness of the…
ERIC Educational Resources Information Center
Brown, Gavin T. L.; Harris, Lois R.; O'Quin, Chrissie; Lane, Kenneth E.
2017-01-01
Multi-group confirmatory factor analysis (MGCFA) allows researchers to determine whether a research inventory elicits similar response patterns across samples. If statistical equivalence in responding is found, then scale score comparisons become possible and samples can be said to be from the same population. This paper illustrates the use of…
Fenning, RM; Baker, BL; Juvonen, J
2009-01-01
This study examined parent-child emotion discourse, children’s independent social information processing, and social skills outcomes in 146 families of 8-year-olds with and without developmental delays. Children’s emergent social-cognitive understanding (internal state understanding, perspective taking, and causal reasoning/problem solving) was coded in the context of parent-child conversations about emotion, and children were interviewed separately to assess social problem solving. Mothers, fathers, and teachers reported on children’s social skills. The proposed strengths-based model partially accounted for social skills differences between typically developing children and children with delays. A multigroup analysis of the model linking emotion discourse to social skills through children’s prosocial problem solving suggested that processes operated similarly across the two groups. Implications for ecologically focused prevention and intervention are discussed. PMID:21410465
ERIC Educational Resources Information Center
Sideridis, Georgios D.; Tsaousis, Ioannis; Al-harbi, Khaleel A.
2015-01-01
The purpose of the present study was to extend the model of measurement invariance by simultaneously estimating invariance across multiple populations in the dichotomous instrument case using multi-group confirmatory factor analytic and multiple indicator multiple causes (MIMIC) methodologies. Using the Arabic version of the General Aptitude Test…
COMPLETE DETERMINATION OF POLARIZATION FOR A HIGH-ENERGY DEUTERON BEAM (thesis)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Button, J
1959-05-01
please delete the no. 17076<>13:017077The P/sub 1/ multigroup code was written for the IBM-704 in order to determine the accuracy of the few- group diffusion scheme with various imposed conditions and also to provide an alternate computational method when this scheme fails to be sufficiently accurate. The code solves for the spatially dependent multigroup flux, taking into account such nuclear phenomena is slowing down of neutrons resulting from elastic and inelastic scattering, the removal of neutrons resulting from epithermal capture and fission resonances, and the regeneration of fist neutrons resulting from fissioning which may occur in any of as manymore » as 80 fast multigroups or in the one thermal group. The code will accept as input a physical description of the reactor (that is: slab, cylindrical, or spherical geometry, number of points and regions, composition description group dependent boundary condition, transverse buckling, and mesh sizes) and a prepared library of nuclear properties of all the isotopes in each composition. The code will produce as output multigroup fluxes, currents, and isotopic slowing-down densities, in addition to pointwise and regionwise few-group macroscopic cross sections. (auth)« less
Homma, Yuko; Zumbo, Bruno D.; Saewyc, Elizabeth M.; Wong, Sabrina T.
2016-01-01
We examined the psychometric properties of scores on a 6-item version of the Multigroup Ethnic Identity Measure (MEIM) among East Asian adolescents in Canada. A series of confirmatory factor analysis (CFA) was conducted for 4,190 East Asians who completed a provincial survey of students in grades 7 to 12. The MEIM measured highly correlated dimensions of ethnic identity (exploration and commitment). Further, multi-group CFA indicated that the scale measured the same constructs on the same metric across three age groups and across four groups with varying degrees of exposure to Canadian and East Asian cultures. The findings suggest the short version of the MEIM can be used to compare levels of ethnic identity across different age or acculturation groups. PMID:27833471
Olson, Gordon Lee
2016-12-06
Here, gray and multigroup radiation is transported through 3D media consisting of spheres randomly placed in a uniform background. Comparisons are made between using constant radii spheres and three different distributions of sphere radii. Because of the computational cost of 3D calculations, only the lowest angle order, n=1, is tested. If the mean chord length is held constant, using different radii distributions makes little difference. This is true for both gray and multigroup solutions. 3D transport solutions are compared to 2D and 1D solutions with the same mean chord lengths. 2D disk and 3D sphere media give solutions that aremore » nearly identical while 1D slab solutions are fundamentally different.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olson, Gordon Lee
Here, gray and multigroup radiation is transported through 3D media consisting of spheres randomly placed in a uniform background. Comparisons are made between using constant radii spheres and three different distributions of sphere radii. Because of the computational cost of 3D calculations, only the lowest angle order, n=1, is tested. If the mean chord length is held constant, using different radii distributions makes little difference. This is true for both gray and multigroup solutions. 3D transport solutions are compared to 2D and 1D solutions with the same mean chord lengths. 2D disk and 3D sphere media give solutions that aremore » nearly identical while 1D slab solutions are fundamentally different.« less
ERIC Educational Resources Information Center
Molenaar, Dylan; Dolan, Conor V.; Wicherts, Jelle M.
2009-01-01
Research into sex differences in general intelligence, g, has resulted in two opposite views. In the first view, a g-difference is nonexistent, while in the second view, g is associated with a male advantage. Past research using Multi-Group Covariance and Mean Structure Analysis (MG-CMSA) found no sex difference in g. This failure raised the…
Fenning, Rachel M; Baker, Bruce L; Juvonen, Jaana
2011-01-01
This study examined parent-child emotion discourse, children's independent social information processing, and social skills outcomes in 146 families of 8-year-olds with and without developmental delays. Children's emergent social-cognitive understanding (internal state understanding, perspective taking, and causal reasoning and problem solving) was coded in the context of parent-child conversations about emotion, and children were interviewed separately to assess social problem solving. Mothers, fathers, and teachers reported on children's social skills. The proposed strengths-based model partially accounted for social skills differences between typically developing children and children with delays. A multigroup analysis of the model linking emotion discourse to social skills through children's prosocial problem solving suggested that processes operated similarly for the two groups. Implications for ecologically focused prevention and intervention are discussed. © 2011 The Authors. Child Development © 2011 Society for Research in Child Development, Inc.
ERIC Educational Resources Information Center
Geiser, Christian; Lehmann, Wolfgang; Eid, Michael
2006-01-01
Items of mental rotation tests can not only be solved by mental rotation but also by other solution strategies. A multigroup latent class analysis of 24 items of the Mental Rotations Test (MRT) was conducted in a sample of 1,695 German pupils and students to find out how many solution strategies can be identified for the items of this test. The…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tominaga, Nozomu; Shibata, Sanshiro; Blinnikov, Sergei I., E-mail: tominaga@konan-u.ac.jp, E-mail: sshibata@post.kek.jp, E-mail: Sergei.Blinnikov@itep.ru
We develop a time-dependent, multi-group, multi-dimensional relativistic radiative transfer code, which is required to numerically investigate radiation from relativistic fluids that are involved in, e.g., gamma-ray bursts and active galactic nuclei. The code is based on the spherical harmonic discrete ordinate method (SHDOM) which evaluates a source function including anisotropic scattering in spherical harmonics and implicitly solves the static radiative transfer equation with ray tracing in discrete ordinates. We implement treatments of time dependence, multi-frequency bins, Lorentz transformation, and elastic Thomson and inelastic Compton scattering to the publicly available SHDOM code. Our code adopts a mixed-frame approach; the source functionmore » is evaluated in the comoving frame, whereas the radiative transfer equation is solved in the laboratory frame. This implementation is validated using various test problems and comparisons with the results from a relativistic Monte Carlo code. These validations confirm that the code correctly calculates the intensity and its evolution in the computational domain. The code enables us to obtain an Eddington tensor that relates the first and third moments of intensity (energy density and radiation pressure) and is frequently used as a closure relation in radiation hydrodynamics calculations.« less
Merz, Erin L; Malcarne, Vanessa L; Roesch, Scott C; Riley, Natasha; Sadler, Georgia Robins
2011-07-01
Depression is a significant problem for ethnic minorities that remains understudied partly due to a lack of strong measures with established psychometric properties. One screening tool, the Patient Health Questionnaire-9 (PHQ-9), which was developed for use in primary care has also gained popularity in research settings. The reliability and validity of the PHQ-9 has been well established among predominantly Caucasian samples, in addition to many minority groups. However, there is little evidence regarding its utility among Hispanic Americans, a large and growing cultural group in the United States. In this study, we investigated the reliability and structural validity of the PHQ-9 in Hispanic American women. A community sample of 479 Latina women from southern California completed the PHQ-9 in their preferred language of English or Spanish. Cronbach's alphas suggested that there was good internal consistency for both the English- and Spanish-language versions. Structural validity was investigated using multigroup confirmatory factor analysis. Results support a similar one-factor structure with equivalent response patterns and variances among English- and Spanish-speaking Latinas. These results suggest that the PHQ-9 can be used with confidence in both English and Spanish versions to screen Latinas for depression.
Merz, Erin L.; Malcarne, Vanessa L.; Roesch, Scott C.; Riley, Natasha; Sadler, Georgia Robins
2014-01-01
Depression is a significant problem for ethnic minorities that remains understudied partly due to a lack of strong measures with established psychometric properties. One screening tool, the Patient Health Questionnaire-9 (PHQ-9), which was developed for use in primary care has also gained popularity in research settings. The reliability and validity of the PHQ-9 has been well established among predominantly Caucasian samples, in addition to many minority groups. However, there is little evidence regarding its utility among Hispanic Americans, a large and growing cultural group in the United States. In this study, we investigated the reliability and structural validity of the PHQ-9 in Hispanic American women. A community sample of 479 Latina women from southern California completed the PHQ-9 in their preferred language of English or Spanish. Cronbach’s alphas suggested that there was good internal consistency for both the English- and Spanish-language versions. Structural validity was investigated using multigroup confirmatory factor analysis (CFA). Results support a similar one-factor structure with equivalent response patterns and variances among English- and Spanish-speaking Latinas. These results suggest that the PHQ-9 can be used with confidence in both English and Spanish versions to screen Latinas for depression. PMID:21787063
Recent developments in multidimensional transport methods for the APOLLO 2 lattice code
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zmijarevic, I.; Sanchez, R.
1995-12-31
A usual method of preparation of homogenized cross sections for reactor coarse-mesh calculations is based on two-dimensional multigroup transport treatment of an assembly together with an appropriate leakage model and reaction-rate-preserving homogenization technique. The actual generation of assembly spectrum codes based on collision probability methods is capable of treating complex geometries (i.e., irregular meshes of arbitrary shape), thus avoiding the modeling error that was introduced in codes with traditional tracking routines. The power and architecture of current computers allow the treatment of spatial domains comprising several mutually interacting assemblies using fine multigroup structure and retaining all geometric details of interest.more » Increasing safety requirements demand detailed two- and three-dimensional calculations for very heterogeneous problems such as control rod positioning, broken Pyrex rods, irregular compacting of mixed- oxide (MOX) pellets at an MOX-UO{sub 2} interface, and many others. An effort has been made to include accurate multi- dimensional transport methods in the APOLLO 2 lattice code. These include extension to three-dimensional axially symmetric geometries of the general-geometry collision probability module TDT and the development of new two- and three-dimensional characteristics methods for regular Cartesian meshes. In this paper we discuss the main features of recently developed multidimensional methods that are currently being tested.« less
Flowing gas, non-nuclear experiments on the gas core reactor
NASA Technical Reports Server (NTRS)
Kunze, J. F.; Suckling, D. H.; Copper, C. G.
1972-01-01
Flow tests were conducted on models of the gas core (cavity) reactor. Variations in cavity wall and injection configurations were aimed at establishing flow patterns that give a maximum of the nuclear criticality eigenvalue. Correlation with the nuclear effect was made using multigroup diffusion theory normalized by previous benchmark critical experiments. Air was used to simulate the hydrogen propellant in the flow tests, and smoked air, argon, or freon to simulate the central nuclear fuel gas. All tests were run in the down-firing direction so that gravitational effects simulated the acceleration effect of a rocket. Results show that acceptable flow patterns with high volume fraction for the simulated nuclear fuel gas and high flow rate ratios of propellant to fuel can be obtained. Using a point injector for the fuel, good flow patterns are obtained by directing the outer gas at high velocity along the cavity wall, using louvered or oblique-angle-honeycomb injection schemes.
The Impact of Neighborhood, Family, and Individual Risk Factors on Toddlers’ Disruptive Behavior
Heberle, Amy E.; Thomas, Yolanda M.; Wagmiller, Robert L.; Briggs-Gowan, Margaret J.; Carter, Alice S.
2014-01-01
Disadvantaged neighborhoods confer risk for behavior problems in school aged children but their impact in toddlerhood is unknown. Relations between toddlers’ disruptive behavior and neighborhood disadvantage, family disadvantage, violence or conflict exposure, parent depressive symptoms, and parenting behavior were examined using multilevel, multi-group (girl/boy) models. Participants were 1204 families (mean child age = 24.7 months). Unique associations between disruptive behavior and all risk factors were observed, but the effect of neighborhood disadvantage was negligible when all of the more proximal factors were accounted for. The results suggest both that children in disadvantaged neighborhoods are at greater risk of behavior problems than children in non-disadvantaged neighborhoods and that optimal prevention/intervention work with these children will attend to proximal risk factors. PMID:24773306
A hybrid multigroup neutron-pattern model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pogosbekyan, L.R.; Lysov, D.A.
In this paper, we use the general approach to construct a multigroup hybrid model for the neutron pattern. The equations are given together with a reasonably economic and simple iterative method of solving them. The algorithm can be used to calculate the pattern and the functionals as well as to correct the constants from the experimental data and to adapt the support over the constants to the engineering programs by reference to precision ones.
A Multigroup Method for the Calculation of Neutron Fluence with a Source Term
NASA Technical Reports Server (NTRS)
Heinbockel, J. H.; Clowdsley, M. S.
1998-01-01
Current research on the Grant involves the development of a multigroup method for the calculation of low energy evaporation neutron fluences associated with the Boltzmann equation. This research will enable one to predict radiation exposure under a variety of circumstances. Knowledge of radiation exposure in a free-space environment is a necessity for space travel, high altitude space planes and satellite design. This is because certain radiation environments can cause damage to biological and electronic systems involving both short term and long term effects. By having apriori knowledge of the environment one can use prediction techniques to estimate radiation damage to such systems. Appropriate shielding can be designed to protect both humans and electronic systems that are exposed to a known radiation environment. This is the goal of the current research efforts involving the multi-group method and the Green's function approach.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rearden, Bradley T.; Jessee, Matthew Anderson
The SCALE Code System is a widely used modeling and simulation suite for nuclear safety analysis and design that is developed, maintained, tested, and managed by the Reactor and Nuclear Systems Division (RNSD) of Oak Ridge National Laboratory (ORNL). SCALE provides a comprehensive, verified and validated, user-friendly tool set for criticality safety, reactor physics, radiation shielding, radioactive source term characterization, and sensitivity and uncertainty analysis. Since 1980, regulators, licensees, and research institutions around the world have used SCALE for safety analysis and design. SCALE provides an integrated framework with dozens of computational modules including 3 deterministic and 3 Monte Carlomore » radiation transport solvers that are selected based on the desired solution strategy. SCALE includes current nuclear data libraries and problem-dependent processing tools for continuous-energy (CE) and multigroup (MG) neutronics and coupled neutron-gamma calculations, as well as activation, depletion, and decay calculations. SCALE includes unique capabilities for automated variance reduction for shielding calculations, as well as sensitivity and uncertainty analysis. SCALE’s graphical user interfaces assist with accurate system modeling, visualization of nuclear data, and convenient access to desired results. SCALE 6.2 represents one of the most comprehensive revisions in the history of SCALE, providing several new capabilities and significant improvements in many existing features.« less
A broad-group cross-section library based on ENDF/B-VII.0 for fast neutron dosimetry Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Alpan, F.A.
2011-07-01
A new ENDF/B-VII.0-based coupled 44-neutron, 20-gamma-ray-group cross-section library was developed to investigate the latest evaluated nuclear data file (ENDF) ,in comparison to ENDF/B-VI.3 used in BUGLE-96, as well as to generate an objective-specific library. The objectives selected for this work consisted of dosimetry calculations for in-vessel and ex-vessel reactor locations, iron atom displacement calculations for reactor internals and pressure vessel, and {sup 58}Ni(n,{gamma}) calculation that is important for gas generation in the baffle plate. The new library was generated based on the contribution and point-wise cross-section-driven (CPXSD) methodology and was applied to one of the most widely used benchmarks, themore » Oak Ridge National Laboratory Pool Critical Assembly benchmark problem. In addition to the new library, BUGLE-96 and an ENDF/B-VII.0-based coupled 47-neutron, 20-gamma-ray-group cross-section library was generated and used with both SNLRML and IRDF dosimetry cross sections to compute reaction rates. All reaction rates computed by the multigroup libraries are within {+-} 20 % of measurement data and meet the U. S. Nuclear Regulatory Commission acceptance criterion for reactor vessel neutron exposure evaluations specified in Regulatory Guide 1.190. (authors)« less
Testing women's propensities to leave their abusive husbands using structural equation modeling.
Choi, Myunghan; Belyea, Michael; Phillips, Linda R; Insel, Kathleen; Min, Sung-Kil
2009-01-01
Many Korean women are just beginning to recognize that what they considered to be normal treatment is actually domestic violence. Many are becoming more intolerant of the abuse and more likely to desire to leave an abusive relationship. The aim of this study was to test, using the framework of sociostructural and psychological-relational power (PRP), a model of Korean women's propensities to leave their abusive husbands. Multigroup structural equation modeling was used to test relationships between variables chosen from the sociostructural power and PRP to explain intolerance to abuse. Married Korean women (n = 184) who self-identified as being abused physically, psychologically, sexually, or financially participated in the study. The multigroup analysis revealed that the relationship of abuse and Hwa-Byung (a culture-bound syndrome that denotes Korean women's anger) with intolerance was supported for women with low education (defined as having an education of high school or less: < or =12 years); also for this group, particularly among the younger women, high power was related to high levels of reported abuse and abuse intolerance. For women in the high-education group (education beyond high school: > or =13 years), high power was related to abuse, Hwa-Byung, and abuse intolerance; age did not influence power. Overall, the multigroup model adequately fitted the sample data (chi2 = 92.057, degree of freedom = 50, p = .000; normal fit index = .926, comparative fix index = .964, root mean square error of approximation = .068, Hoelter's critical number = 152), demonstrating that education is a crucial moderator of Korean women's attitude toward the unacceptability of abuse and propensity to terminate the marriage. This study found support for a model of abuse intolerance using the framework of sociostructural power and PRP, primarily for the low-education group. Hwa-Byung was a mediating factor that contributed to intolerance to abuse in women with low education. This study highlights the importance of understanding the cultural assumptions that guide Korean women's beliefs and behaviors about abuse intolerance, suggesting that effective intervention programs should be specific to age and education, including a focus on resource availability, which could clarify the variations in Korean women's responses to abuse intolerance.
Coley, Rebekah Levine; Kull, Melissa A; Carrano, Jennifer
2014-02-01
This study assessed prospective, bidirectional associations between maternal endorsement of spanking and children's internalizing and externalizing behavior problems in low-income urban African American and Hispanic (N = 592) families drawn from the Three City Study. Children in sample families were followed from early childhood through middle childhood with 3 sets of interviews and assessments at ages 3, 4, and 9 years. Cross-lagged path analyses tested longitudinal bidirectional associations between parental endorsement of spanking and children's internalizing and externalizing problems, with multigroup comparisons employed to test group differences between race/ethnic groups. African American and Hispanic mothers showed similar endorsements of spanking. Results suggest that associations between spanking endorsement and child functioning were due primarily to parenting effects, with spanking predicting changes in children's behaviors, rather than child evocative effects, with limited evidence of child behaviors predicting changes in parental spanking. Maternal spanking endorsement predicted short-term decreases in children's internalizing problems in early childhood, but over the longer term spanking was associated with increased internalizing and externalizing problems for both African American and Hispanic children in middle childhood among economically disadvantaged families.
A Conditional Curie-Weiss Model for Stylized Multi-group Binary Choice with Social Interaction
NASA Astrophysics Data System (ADS)
Opoku, Alex Akwasi; Edusei, Kwame Owusu; Ansah, Richard Kwame
2018-04-01
This paper proposes a conditional Curie-Weiss model as a model for decision making in a stylized society made up of binary decision makers that face a particular dichotomous choice between two options. Following Brock and Durlauf (Discrete choice with social interaction I: theory, 1955), we set-up both socio-economic and statistical mechanical models for the choice problem. We point out when both the socio-economic and statistical mechanical models give rise to the same self-consistent equilibrium mean choice level(s). Phase diagram of the associated statistical mechanical model and its socio-economic implications are discussed.
Efficient solution of the simplified P N equations
Hamilton, Steven P.; Evans, Thomas M.
2014-12-23
We show new solver strategies for the multigroup SPN equations for nuclear reactor analysis. By forming the complete matrix over space, moments, and energy a robust set of solution strategies may be applied. Moreover, power iteration, shifted power iteration, Rayleigh quotient iteration, Arnoldi's method, and a generalized Davidson method, each using algebraic and physics-based multigrid preconditioners, have been compared on C5G7 MOX test problem as well as an operational PWR model. These results show that the most ecient approach is the generalized Davidson method, that is 30-40 times faster than traditional power iteration and 6-10 times faster than Arnoldi's method.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haghighat, A.; Sjoden, G.E.; Wagner, J.C.
In the past 10 yr, the Penn State Transport Theory Group (PSTTG) has concentrated its efforts on developing accurate and efficient particle transport codes to address increasing needs for efficient and accurate simulation of nuclear systems. The PSTTG's efforts have primarily focused on shielding applications that are generally treated using multigroup, multidimensional, discrete ordinates (S{sub n}) deterministic and/or statistical Monte Carlo methods. The difficulty with the existing public codes is that they require significant (impractical) computation time for simulation of complex three-dimensional (3-D) problems. For the S{sub n} codes, the large memory requirements are handled through the use of scratchmore » files (i.e., read-from and write-to-disk) that significantly increases the necessary execution time. Further, the lack of flexible features and/or utilities for preparing input and processing output makes these codes difficult to use. The Monte Carlo method becomes impractical because variance reduction (VR) methods have to be used, and normally determination of the necessary parameters for the VR methods is very difficult and time consuming for a complex 3-D problem. For the deterministic method, the authors have developed the 3-D parallel PENTRAN (Parallel Environment Neutral-particle TRANsport) code system that, in addition to a parallel 3-D S{sub n} solver, includes pre- and postprocessing utilities. PENTRAN provides for full phase-space decomposition, memory partitioning, and parallel input/output to provide the capability of solving large problems in a relatively short time. Besides having a modular parallel structure, PENTRAN has several unique new formulations and features that are necessary for achieving high parallel performance. For the Monte Carlo method, the major difficulty currently facing most users is the selection of an effective VR method and its associated parameters. For complex problems, generally, this process is very time consuming and may be complicated due to the possibility of biasing the results. In an attempt to eliminate this problem, the authors have developed the A{sup 3}MCNP (automated adjoint accelerated MCNP) code that automatically prepares parameters for source and transport biasing within a weight-window VR approach based on the S{sub n} adjoint function. A{sup 3}MCNP prepares the necessary input files for performing multigroup, 3-D adjoint S{sub n} calculations using TORT.« less
CRASH: A BLOCK-ADAPTIVE-MESH CODE FOR RADIATIVE SHOCK HYDRODYNAMICS-IMPLEMENTATION AND VERIFICATION
DOE Office of Scientific and Technical Information (OSTI.GOV)
Van der Holst, B.; Toth, G.; Sokolov, I. V.
We describe the Center for Radiative Shock Hydrodynamics (CRASH) code, a block-adaptive-mesh code for multi-material radiation hydrodynamics. The implementation solves the radiation diffusion model with a gray or multi-group method and uses a flux-limited diffusion approximation to recover the free-streaming limit. Electrons and ions are allowed to have different temperatures and we include flux-limited electron heat conduction. The radiation hydrodynamic equations are solved in the Eulerian frame by means of a conservative finite-volume discretization in either one-, two-, or three-dimensional slab geometry or in two-dimensional cylindrical symmetry. An operator-split method is used to solve these equations in three substeps: (1)more » an explicit step of a shock-capturing hydrodynamic solver; (2) a linear advection of the radiation in frequency-logarithm space; and (3) an implicit solution of the stiff radiation diffusion, heat conduction, and energy exchange. We present a suite of verification test problems to demonstrate the accuracy and performance of the algorithms. The applications are for astrophysics and laboratory astrophysics. The CRASH code is an extension of the Block-Adaptive Tree Solarwind Roe Upwind Scheme (BATS-R-US) code with a new radiation transfer and heat conduction library and equation-of-state and multi-group opacity solvers. Both CRASH and BATS-R-US are part of the publicly available Space Weather Modeling Framework.« less
Santoro, Maya S; Van Liew, Charles; Holloway, Breanna; McKinnon, Symone; Little, Timothy; Cronan, Terry A
2016-08-01
The present study explores patterns of parity and disparity in the effect of filial responsibility on health-related evaluations and caregiving decisions. Participants who identified as White, Black, Hispanic, or Asian/Pacific Islander read a vignette about an older man needing medical care. They were asked to imagine that they were the man's son and answer questions regarding their likelihood of hiring a health care advocate (HCA) for services related to the father's care. A multigroup (ethnicity) path analysis was performed, and an intercept invariant multigroup model fits the data best. Direct and indirect effect estimation showed that filial responsibility mediated the relationship between both the perceived severity of the father's medical condition and the perceived need for medical assistance and the likelihood of hiring an HCA only for White and Hispanic participants, albeit differently. The findings demonstrate that culture and ethnicity affect health evaluations and caregiving decision making. © The Author(s) 2015.
2017-01-01
Abstract Cross-national data production in social science research has increased dramatically in recent decades. Assessing the comparability of data is necessary before drawing substantive conclusions that are based on cross-national data. Researchers assessing data comparability typically use either quantitative methods such as multigroup confirmatory factor analysis or qualitative methods such as online probing. Because both methods have complementary strengths and weaknesses, this study applies both multigroup confirmatory factor analysis and online probing in a mixed-methods approach to assess the comparability of constructive patriotism and nationalism, two important concepts in the study of national identity. Previous measurement invariance tests failed to achieve scalar measurement invariance, which prohibits a cross-national comparison of latent means (Davidov 2009). The arrival of the 2013 ISSP Module on National Identity has encouraged a reassessment of both constructs and a push to understand why scalar invariance cannot be achieved. Using the example of constructive patriotism and nationalism, this study demonstrates how the combination of multigroup confirmatory factor analysis and online probing can uncover and explain issues related to cross-national comparability. PMID:28579643
Consensus oriented fuzzified decision support for oil spill contingency management.
Liu, Xin; Wirtz, Kai W
2006-06-30
Studies on multi-group multi-criteria decision-making problems for oil spill contingency management are in their infancy. This paper presents a second-order fuzzy comprehensive evaluation (FCE) model to resolve decision-making problems in the area of contingency management after environmental disasters such as oil spills. To assess the performance of different oil combat strategies, second-order FCE allows for the utilization of lexical information, the consideration of ecological and socio-economic criteria and the involvement of a variety of stakeholders. On the other hand, the new approach can be validated by using internal and external checks, which refer to sensitivity tests regarding its internal setups and comparisons with other methods, respectively. Through a case study, the Pallas oil spill in the German Bight in 1998, it is demonstrated that this approach can help decision makers who search for an optimal strategy in multi-thread contingency problems and has a wider application potential in the field of integrated coastal zone management.
NASA Astrophysics Data System (ADS)
Burns, Kimberly Ann
The accurate and efficient simulation of coupled neutron-photon problems is necessary for several important radiation detection applications. Examples include the detection of nuclear threats concealed in cargo containers and prompt gamma neutron activation analysis for nondestructive determination of elemental composition of unknown samples. In these applications, high-resolution gamma-ray spectrometers are used to preserve as much information as possible about the emitted photon flux, which consists of both continuum and characteristic gamma rays with discrete energies. Monte Carlo transport is the most commonly used modeling tool for this type of problem, but computational times for many problems can be prohibitive. This work explores the use of coupled Monte Carlo-deterministic methods for the simulation of neutron-induced photons for high-resolution gamma-ray spectroscopy applications. RAdiation Detection Scenario Analysis Toolbox (RADSAT), a code which couples deterministic and Monte Carlo transport to perform radiation detection scenario analysis in three dimensions [1], was used as the building block for the methods derived in this work. RADSAT was capable of performing coupled deterministic-Monte Carlo simulations for gamma-only and neutron-only problems. The purpose of this work was to develop the methodology necessary to perform coupled neutron-photon calculations and add this capability to RADSAT. Performing coupled neutron-photon calculations requires four main steps: the deterministic neutron transport calculation, the neutron-induced photon spectrum calculation, the deterministic photon transport calculation, and the Monte Carlo detector response calculation. The necessary requirements for each of these steps were determined. A major challenge in utilizing multigroup deterministic transport methods for neutron-photon problems was maintaining the discrete neutron-induced photon signatures throughout the simulation. Existing coupled neutron-photon cross-section libraries and the methods used to produce neutron-induced photons were unsuitable for high-resolution gamma-ray spectroscopy applications. Central to this work was the development of a method for generating multigroup neutron-photon cross-sections in a way that separates the discrete and continuum photon emissions so the neutron-induced photon signatures were preserved. The RADSAT-NG cross-section library was developed as a specialized multigroup neutron-photon cross-section set for the simulation of high-resolution gamma-ray spectroscopy applications. The methodology and cross sections were tested using code-to-code comparison with MCNP5 [2] and NJOY [3]. A simple benchmark geometry was used for all cases compared with MCNP. The geometry consists of a cubical sample with a 252Cf neutron source on one side and a HPGe gamma-ray spectrometer on the opposing side. Different materials were examined in the cubical sample: polyethylene (C2H4), P, N, O, and Fe. The cross sections for each of the materials were compared to cross sections collapsed using NJOY. Comparisons of the volume-averaged neutron flux within the sample, volume-averaged photon flux within the detector, and high-purity gamma-ray spectrometer response (only for polyethylene) were completed using RADSAT and MCNP. The code-to-code comparisons show promising results for the coupled Monte Carlo-deterministic method. The RADSAT-NG cross-section production method showed good agreement with NJOY for all materials considered although some additional work is needed in the resonance region and in the first and last energy bin. Some cross section discrepancies existed in the lowest and highest energy bin, but the overall shape and magnitude of the two methods agreed. For the volume-averaged photon flux within the detector, typically the five most intense lines agree to within approximately 5% of the MCNP calculated flux for all of materials considered. The agreement in the code-to-code comparisons cases demonstrates a proof-of-concept of the method for use in RADSAT for coupled neutron-photon problems in high-resolution gamma-ray spectroscopy applications. One of the primary motivators for using the coupled method over pure Monte Carlo method is the potential for significantly lower computational times. For the code-to-code comparison cases, the run times for RADSAT were approximately 25--500 times shorter than for MCNP, as shown in Table 1. This was assuming a 40 mCi 252Cf neutron source and 600 seconds of "real-world" measurement time. The only variance reduction technique implemented in the MCNP calculation was forward biasing of the source toward the sample target. Improved MCNP runtimes could be achieved with the addition of more advanced variance reduction techniques.
A comparison of fitness-case sampling methods for genetic programming
NASA Astrophysics Data System (ADS)
Martínez, Yuliana; Naredo, Enrique; Trujillo, Leonardo; Legrand, Pierrick; López, Uriel
2017-11-01
Genetic programming (GP) is an evolutionary computation paradigm for automatic program induction. GP has produced impressive results but it still needs to overcome some practical limitations, particularly its high computational cost, overfitting and excessive code growth. Recently, many researchers have proposed fitness-case sampling methods to overcome some of these problems, with mixed results in several limited tests. This paper presents an extensive comparative study of four fitness-case sampling methods, namely: Interleaved Sampling, Random Interleaved Sampling, Lexicase Selection and Keep-Worst Interleaved Sampling. The algorithms are compared on 11 symbolic regression problems and 11 supervised classification problems, using 10 synthetic benchmarks and 12 real-world data-sets. They are evaluated based on test performance, overfitting and average program size, comparing them with a standard GP search. Comparisons are carried out using non-parametric multigroup tests and post hoc pairwise statistical tests. The experimental results suggest that fitness-case sampling methods are particularly useful for difficult real-world symbolic regression problems, improving performance, reducing overfitting and limiting code growth. On the other hand, it seems that fitness-case sampling cannot improve upon GP performance when considering supervised binary classification.
Coley, Rebekah Levine; Kull, Melissa A.; Carrano, Jennifer
2014-01-01
This study assessed prospective, bidirectional associations between maternal endorsement of spanking and children’s internalizing and externalizing behavior problems in low-income urban African American and Hispanic (N = 592) families drawn from the Three City Study. Children in sample families were followed from early childhood through middle childhood with three sets of interviews and assessments at ages 3, 4, and 9 years. Cross-lagged path analyses tested longitudinal bidirectional associations between parental endorsement of spanking and children’s internalizing and externalizing problems, with multi-group comparisons employed to test group differences between race/ethnic groups. African American and Hispanic mothers showed similar endorsements of spanking. Results suggest that associations between spanking endorsement and child functioning were due primarily to parenting effects, with spanking predicting changes in children’s behaviors, rather than child evocative effects, with limited evidence of child behaviors predicting changes in parental spanking. Maternal spanking endorsement predicted short-term decreases in children’s internalizing problems in early childhood, but over the longer term spanking was associated with increased internalizing and externalizing problems for both African American and Hispanic children in middle childhood among economically disadvantaged families. PMID:24364363
Academic and social motives and drinking behavior.
Vaughan, Ellen L; Corbin, William R; Fromme, Kim
2009-12-01
This longitudinal study of 1,447 first-time college students tested separate time-varying covariate models of the relations between academic and social motives/behaviors and alcohol use and related problems from senior year of high school through the end of the second year in college. Structural equation models identified small but significant inverse relations between academic motives/behaviors and alcohol use across all time points, with relations of somewhat larger magnitude between academic motives/behaviors and alcohol-related problems across all semesters other than senior year in high school. At all time points, there were much larger positive relations between social motives/behaviors and alcohol use across all semesters, with smaller but significant relations between social motives/behaviors and alcohol-related problems. Multi-group models found considerable consistency in the relations between motives/behaviors and alcohol-related outcomes across gender, race/ethnicity, and family history of alcohol problems, although academic motives/behaviors played a stronger protective role for women, and social motives were a more robust risk factor for Caucasian and Latino students and individuals with a positive family history of alcohol problems. Implications for alcohol prevention efforts among college students are discussed. Copyright 2009 APA
Use of SCALE Continuous-Energy Monte Carlo Tools for Eigenvalue Sensitivity Coefficient Calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Perfetti, Christopher M; Rearden, Bradley T
2013-01-01
The TSUNAMI code within the SCALE code system makes use of eigenvalue sensitivity coefficients for an extensive number of criticality safety applications, such as quantifying the data-induced uncertainty in the eigenvalue of critical systems, assessing the neutronic similarity between different critical systems, and guiding nuclear data adjustment studies. The need to model geometrically complex systems with improved fidelity and the desire to extend TSUNAMI analysis to advanced applications has motivated the development of a methodology for calculating sensitivity coefficients in continuous-energy (CE) Monte Carlo applications. The CLUTCH and Iterated Fission Probability (IFP) eigenvalue sensitivity methods were recently implemented in themore » CE KENO framework to generate the capability for TSUNAMI-3D to perform eigenvalue sensitivity calculations in continuous-energy applications. This work explores the improvements in accuracy that can be gained in eigenvalue and eigenvalue sensitivity calculations through the use of the SCALE CE KENO and CE TSUNAMI continuous-energy Monte Carlo tools as compared to multigroup tools. The CE KENO and CE TSUNAMI tools were used to analyze two difficult models of critical benchmarks, and produced eigenvalue and eigenvalue sensitivity coefficient results that showed a marked improvement in accuracy. The CLUTCH sensitivity method in particular excelled in terms of efficiency and computational memory requirements.« less
Multi-group measurement invariance of the multiple sclerosis walking scale-12?
Motl, Robert W; Mullen, Sean; McAuley, Edward
2012-03-01
One primary assumption underlying the interpretation of composite multiple sclerosis walking scale-12 (MSWS-12) scores across levels of disability status is multi-group measurement invariance. This assumption was tested in the present study between samples that differed in self-reported disability status. Participants (n = 867) completed a battery of questionnaires that included the MSWS-12 and patient-determined disease step (PDDS) scale. The multi-group invariance was tested between samples that had PDDS scores of ≤2 (i.e. no mobility limitation; n = 470) and PDDS scores ≥3 (onset of mobility limitation; n = 397) using Mplus 6·0. The omnibus test of equal covariance matrices indicated that the MSWS-12 was not invariant between the two samples that differed in disability status. The source of non-invariance occurred with the initial equivalence test of the factor structure itself. We provide evidence that questions the unambiguous interpretation of scores from the MSWS-12 as a measure of walking impairment between samples of persons with multiple sclerosis who differ in disability status.
Mixed Legendre moments and discrete scattering cross sections for anisotropy representation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Calloo, A.; Vidal, J. F.; Le Tellier, R.
2012-07-01
This paper deals with the resolution of the integro-differential form of the Boltzmann transport equation for neutron transport in nuclear reactors. In multigroup theory, deterministic codes use transfer cross sections which are expanded on Legendre polynomials. This modelling leads to negative values of the transfer cross section for certain scattering angles, and hence, the multigroup scattering source term is wrongly computed. The first part compares the convergence of 'Legendre-expanded' cross sections with respect to the order used with the method of characteristics (MOC) for Pressurised Water Reactor (PWR) type cells. Furthermore, the cross section is developed using piecewise-constant functions, whichmore » better models the multigroup transfer cross section and prevents the occurrence of any negative value for it. The second part focuses on the method of solving the transport equation with the above-mentioned piecewise-constant cross sections for lattice calculations for PWR cells. This expansion thereby constitutes a 'reference' method to compare the conventional Legendre expansion to, and to determine its pertinence when applied to reactor physics calculations. (authors)« less
A new multigroup method for cross-sections that vary rapidly in energy
Haut, Terry Scot; Ahrens, Cory D.; Jonko, Alexandra; ...
2016-11-04
Here, we present a numerical method for solving the time-independent thermal radiative transfer (TRT) equation or the neutron transport (NT) equation when the opacity (cross-section) varies rapidly in frequency (energy) on the microscale ε; ε corresponds to the characteristic spacing between absorption lines or resonances, and is much smaller than the macroscopic frequency (energy) variation of interest. The approach is based on a rigorous homogenization of the TRT/NT equation in the frequency (energy) variable. Discretization of the homogenized TRT/NT equation results in a multigroup-type system, and can therefore be solved by standard methods.
New Methodologies for Generation of Multigroup Cross Sections for Shielding Applications
NASA Astrophysics Data System (ADS)
Arzu Alpan, F.; Haghighat, Alireza
2003-06-01
Coupled neutron and gamma multigroup (broad-group) libraries used for Light Water Reactor shielding and dosimetry commonly include 47-neutron and 20-gamma groups. These libraries are derived from the 199-neutron, 42-gamma fine-group VITAMIN-B6 library. In this paper, we introduce modifications to the generation procedure of the broad-group libraries. Among these modifications, we show that the fine-group structure and collapsing technique have the largest impact. We demonstrate that a more refined fine-group library and the bi-linear adjoint weighting collapsing technique can improve the accuracy of transport calculation results.
Revision, Criterion Validity, and Multi-group Assessment of the Reactions to Homosexuality Scale
Smolenski, Derek J.; Diamond, Pamela M.; Ross, Michael W.; Simon Rosser, B. R.
2010-01-01
Internalized homonegativity encompasses negative attitudes toward one’s own sexual orientation, and is associated with negative mental and physical health outcomes. The Reactions to Homosexuality scale (Ross & Rosser, 1996), an instrument used to measure internalized homonegativity, has been criticized for including content irrelevant to the construct of internalized homonegativity. We revised the scale using exploratory and confirmatory factor analyses, and identified a seven-item, three-factor reduced version that demonstrated measurement invariance across racial/ethnic categorizations and between English and Spanish versions. We also investigated criterion validity by estimating correlations with hypothesized outcomes associated with outness, relationship status, sexual orientation, and gay community affiliation. The evidence of measurement invariance suggests that this scale is appropriate for pluralistic treatment or study groups. PMID:20954058
Measurement invariance via multigroup SEM: Issues and solutions with chi-square-difference tests.
Yuan, Ke-Hai; Chan, Wai
2016-09-01
Multigroup structural equation modeling (SEM) plays a key role in studying measurement invariance and in group comparison. When population covariance matrices are deemed not equal across groups, the next step to substantiate measurement invariance is to see whether the sample covariance matrices in all the groups can be adequately fitted by the same factor model, called configural invariance. After configural invariance is established, cross-group equalities of factor loadings, error variances, and factor variances-covariances are then examined in sequence. With mean structures, cross-group equalities of intercepts and factor means are also examined. The established rule is that if the statistic at the current model is not significant at the level of .05, one then moves on to testing the next more restricted model using a chi-square-difference statistic. This article argues that such an established rule is unable to control either Type I or Type II errors. Analysis, an example, and Monte Carlo results show why and how chi-square-difference tests are easily misused. The fundamental issue is that chi-square-difference tests are developed under the assumption that the base model is sufficiently close to the population, and a nonsignificant chi-square statistic tells little about how good the model is. To overcome this issue, this article further proposes that null hypothesis testing in multigroup SEM be replaced by equivalence testing, which allows researchers to effectively control the size of misspecification before moving on to testing a more restricted model. R code is also provided to facilitate the applications of equivalence testing for multigroup SEM. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Verdam, Mathilde G E; Oort, Frans J; van der Linden, Yvette M; Sprangers, Mirjam A G
2015-03-01
Missing data due to attrition present a challenge for the assessment and interpretation of change and response shift in HRQL outcomes. The objective was to handle such missingness and to assess response shift and 'true change' with the use of an attrition-based multigroup structural equation modeling (SEM) approach. Functional limitations and health impairments were measured in 1,157 cancer patients, who were treated with palliative radiotherapy for painful bone metastases, before [time (T) 0], every week after treatment (T1 through T12), and then monthly for up to 2 years (T13 through T24). To handle missing data due to attrition, the SEM procedure was extended to a multigroup approach, in which we distinguished three groups: short survival (3-5 measurements), medium survival (6-12 measurements), and long survival (>12 measurements). Attrition after third, sixth, and 13th measurement occasions was 11, 24, and 41 %, respectively. Results show that patterns of change in functional limitations and health impairments differ between patients with short, medium, or long survival. Moreover, three response-shift effects were detected: recalibration of 'pain' and 'sickness' and reprioritization of 'physical functioning.' If response-shift effects would not have been taken into account, functional limitations and health impairments would generally be underestimated across measurements. The multigroup SEM approach enables the analysis of data from patients with different patterns of missing data due to attrition. This approach does not only allow for detection of response shift and assessment of true change across measurements, but also allow for detection of differences in response shift and true change across groups of patients with different attrition rates.
Parallel and Distributed Methods for Constrained Nonconvex Optimization—Part I: Theory
NASA Astrophysics Data System (ADS)
Scutari, Gesualdo; Facchinei, Francisco; Lampariello, Lorenzo
2017-04-01
In Part I of this paper, we proposed and analyzed a novel algorithmic framework for the minimization of a nonconvex (smooth) objective function, subject to nonconvex constraints, based on inner convex approximations. This Part II is devoted to the application of the framework to some resource allocation problems in communication networks. In particular, we consider two non-trivial case-study applications, namely: (generalizations of) i) the rate profile maximization in MIMO interference broadcast networks; and the ii) the max-min fair multicast multigroup beamforming problem in a multi-cell environment. We develop a new class of algorithms enjoying the following distinctive features: i) they are \\emph{distributed} across the base stations (with limited signaling) and lead to subproblems whose solutions are computable in closed form; and ii) differently from current relaxation-based schemes (e.g., semidefinite relaxation), they are proved to always converge to d-stationary solutions of the aforementioned class of nonconvex problems. Numerical results show that the proposed (distributed) schemes achieve larger worst-case rates (resp. signal-to-noise interference ratios) than state-of-the-art centralized ones while having comparable computational complexity.
Multigroup cross section library for GFR2400
NASA Astrophysics Data System (ADS)
Čerba, Štefan; Vrban, Branislav; Lüley, Jakub; Haščík, Ján; Nečas, Vladimír
2017-09-01
In this paper the development and optimization of the SBJ_E71 multigroup cross section library for GFR2400 applications is discussed. A cross section processing scheme, merging Monte Carlo and deterministic codes, was developed. Several fine and coarse group structures and two weighting flux options were analysed through 18 benchmark experiments selected from the handbook of ICSBEP and based on performed similarity assessments. The performance of the collapsed version of the SBJ_E71 library was compared with MCNP5 CE ENDF/B VII.1 and the Korean KAFAX-E70 library. The comparison was made based on integral parameters of calculations performed on full core homogenous models.
The Group-Level Consequences of Sexual Conflict in Multigroup Populations
Eldakar, Omar Tonsi; Gallup, Andrew C.
2011-01-01
In typical sexual conflict scenarios, males best equipped to exploit females are favored locally over more prudent males, despite reducing female fitness. However, local advantage is not the only relevant form of selection. In multigroup populations, groups with less sexual conflict will contribute more offspring to the next generation than higher conflict groups, countering the local advantage of harmful males. Here, we varied male aggression within-and between-groups in a laboratory population of water striders and measured resulting differences in local population growth over a period of three weeks. The overall pool fitness (i.e., adults produced) of less aggressive pools exceeded that of high aggression pools by a factor of three, with the high aggression pools essentially experiencing no population growth over the course of the study. When comparing the fitness of individuals across groups, aggression appeared to be under stabilizing selection in the multigroup population. The use of contextual analysis revealed that overall stabilizing selection was a product of selection favoring aggression within groups, but selected against it at the group-level. Therefore, this report provides further evidence to show that what evolves in the total population is not merely an extension of within-group dynamics. PMID:22039491
Munayer, Salim J; Horenczyk, Gabriel
2014-10-01
Grounded in a contextual approach to acculturation of minorities, this study examines changes in acculturation orientations among Palestinian Christian Arab adolescents in Israel following the "lost decade of Arab-Jewish coexistence." Multi-group acculturation orientations among 237 respondents were assessed vis-à-vis two majorities--Muslim Arabs and Israeli Jews--and compared to 1998 data. Separation was the strongest endorsed orientation towards both majority groups. Comparisons with the 1998 data also show a weakening of the Integration attitude towards Israeli Jews, and also distancing from Muslim Arabs. For the examination of the "Westernisation" hypothesis, multi-dimensional scaling (MDS) analyses of perceptions of Self and group values clearly showed that, after 10 years, Palestinian Christian Arabs perceive Israeli Jewish culture as less close to Western culture, and that Self and the Christian Arab group have become much closer, suggesting an increasing identification of Palestinian Christian Arab adolescents with their ethnoreligious culture. We discuss the value of a multi-group, multi-method, and multi-wave approach to the examination of the role of the political context in acculturation processes. © 2014 International Union of Psychological Science.
Geospatial Data Fusion and Multigroup Decision Support for Surface Water Quality Management
NASA Astrophysics Data System (ADS)
Sun, A. Y.; Osidele, O.; Green, R. T.; Xie, H.
2010-12-01
Social networking and social media have gained significant popularity and brought fundamental changes to many facets of our everyday life. With the ever-increasing adoption of GPS-enabled gadgets and technology, location-based content is likely to play a central role in social networking sites. While location-based content is not new to the geoscience community, where geographic information systems (GIS) are extensively used, the delivery of useful geospatial data to targeted user groups for decision support is new. Decision makers and modelers ought to make more effective use of the new web-based tools to expand the scope of environmental awareness education, public outreach, and stakeholder interaction. Environmental decision processes are often rife with uncertainty and controversy, requiring integration of multiple sources of information and compromises between diverse interests. Fusing of multisource, multiscale environmental data for multigroup decision support is a challenging task. Toward this goal, a multigroup decision support platform should strive to achieve transparency, impartiality, and timely synthesis of information. The latter criterion often constitutes a major technical bottleneck to traditional GIS-based media, featuring large file or image sizes and requiring special processing before web deployment. Many tools and design patterns have appeared in recent years to ease the situation somewhat. In this project, we explore the use of Web 2.0 technologies for “pushing” location-based content to multigroups involved in surface water quality management and decision making. In particular, our granular bottom-up approach facilitates effective delivery of information to most relevant user groups. Our location-based content includes in-situ and remotely sensed data disseminated by NASA and other national and local agencies. Our project is demonstrated for managing the total maximum daily load (TMDL) program in the Arroyo Colorado coastal river basin in Texas. The overall design focuses on assigning spatial information to decision support elements and on efficiently using Web 2.0 technologies to relay scientific information to the nonscientific community. We conclude that (i) social networking, if appropriately used, has great potential for mitigating difficulty associated with multigroup decision making; (ii) all potential stakeholder groups should be involved in creating a useful decision support system; and (iii) environmental decision support systems should be considered a must-have, instead of an optional component of TMDL decision support projects. Acknowledgment: This project was supported by NASA grant NNX09AR63G.
Monte Carlo capabilities of the SCALE code system
Rearden, Bradley T.; Petrie, Jr., Lester M.; Peplow, Douglas E.; ...
2014-09-12
SCALE is a broadly used suite of tools for nuclear systems modeling and simulation that provides comprehensive, verified and validated, user-friendly capabilities for criticality safety, reactor physics, radiation shielding, and sensitivity and uncertainty analysis. For more than 30 years, regulators, licensees, and research institutions around the world have used SCALE for nuclear safety analysis and design. SCALE provides a “plug-and-play” framework that includes three deterministic and three Monte Carlo radiation transport solvers that can be selected based on the desired solution, including hybrid deterministic/Monte Carlo simulations. SCALE includes the latest nuclear data libraries for continuous-energy and multigroup radiation transport asmore » well as activation, depletion, and decay calculations. SCALE’s graphical user interfaces assist with accurate system modeling, visualization, and convenient access to desired results. SCALE 6.2 will provide several new capabilities and significant improvements in many existing features, especially with expanded continuous-energy Monte Carlo capabilities for criticality safety, shielding, depletion, and sensitivity and uncertainty analysis. Finally, an overview of the Monte Carlo capabilities of SCALE is provided here, with emphasis on new features for SCALE 6.2.« less
Cadenas, Germán A; Bernstein, Bianca L; Tracey, Terence J G
2018-05-21
We used the model of critical consciousness (CC; Freire, 1973) to examine college persistence in a sample of Hispanic Deferred Action for Childhood Arrivals (DACA) college students in contrast to Hispanic and non-Hispanic White U.S. citizens. To do this, we looked to social cognitive career theory (Lent, Brown, & Hackett, 1994) to clarify the development of CC and its association with college persistence in students facing marginalization due to immigration status and racial/ethnic identity. The sample consisted of 368 undergraduate college students, including 89 Hispanic DACA recipients, 88 Hispanics with U.S. citizenship, and 191 non-Hispanic Whites with U.S. citizenship. Students completed scales on intent to persist in college, political self-efficacy, political outcome expectations, critical reflection, critical action, and supports and barriers for critical action. The data were examined using multigroup structural equation modeling; goodness of fit indices suggested good model fit for all groups. Tests of structural invariance revealed that 7 relational paths were equal across student groups, while race/ethnicity and immigration status differentiated the strength of 7 paths. Our findings indicate that there are differences in how Hispanic DACA students experience CC in relation to support for their political advocacy and activism. Findings also highlight that political outcome expectations predicted higher intent to persist in college for all students, including Hispanic DACA students. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
van Horn, Joan E
2018-06-01
This article investigates the measurement and structural invariance of a newly developed self-report questionnaire, the Forensic Symptoms Inventory-Revised, aimed at measuring eight cognitive, emotional, and behavioral deficits (aggression, lack of social support, problematic substance use, lack of concentration, anger, poor self-regulation, impulsivity, and sexual problems) among adult forensic outpatients. The sample consisted of 716 outpatients (603 males, 113 females) with a mean age of 38.19 (SD = 12.47). Multi-Group Confirmatory Factor Analyses supported the measurement and structural invariance with respect to gender and age groups (18-23 years and ≥24 years). Between-group comparisons revealed that, compared to females, male outpatients reported more substance related problems, as well as incapacities to control verbal and/or physical aggression. Compared to adults, young adults displayed more inadequate self-regulation skills and reported more social support. These findings may promote the formulation of gender- and age-specific treatment goals.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wollaber, Allan Benton; Park, HyeongKae; Lowrie, Robert Byron
Recent efforts at Los Alamos National Laboratory to develop a moment-based, scale-bridging [or high-order (HO)–low-order (LO)] algorithm for solving large varieties of the transport (kinetic) systems have shown promising results. A part of our ongoing effort is incorporating this methodology into the framework of the Eulerian Applications Project to achieve algorithmic acceleration of radiationhydrodynamics simulations in production software. By starting from the thermal radiative transfer equations with a simple material-motion correction, we derive a discretely consistent energy balance equation (LO equation). We demonstrate that the corresponding LO system for the Monte Carlo HO solver is closely related to the originalmore » LO system without material-motion corrections. We test the implementation on a radiative shock problem and show consistency between the energy densities and temperatures in the HO and LO solutions as well as agreement with the semianalytic solution. We also test the approach on a more challenging two-dimensional problem and demonstrate accuracy enhancements and algorithmic speedups. This paper extends a recent conference paper by including multigroup effects.« less
S/sub n/ analysis of the TRX metal lattices with ENDF/B version III data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wheeler, F.J.; Pearlstein, S.
1975-03-01
Two critical assemblies, designated as thermal-reactor benchmarks TRX-1 and TRX-2 for ENDF/B data testing, were analyzed using the one-dimensional S/sub n/-theory code SCAMP. The two assemblies were simple lattices of aluminum-clad, uranium-metal fuel rods in triangular arrays with D$sub 2$O as moderator and reflector. The fuel was low-enriched (1.3 percent $sup 235$U), 0.387-inch in diameter and had an active height of 48 inches. The volume ratio of water to uranium was 2.35 for the TRX-1 lattice and 4.02 for TRX-2. Full-core S/sub n/ calculations based on Version III data were performed for these assemblies and the results obtained were comparedmore » with the measured values of the multiplication factors, the ratio of epithermal-to-thermal neutron capture in $sup 238$U, the ratio of epithermal-to-thermal fission in $sup 235$U, the ratio of $sup 238$U fission to $sup 235$U fission, and the ratio of capture in $sup 238$U to fission in $sup 235$U. Reaction rates were obtained from a central region of the full- core problems. Multigroup cross sections for the reactor calculation were obtained from S/sub n/ cell calculations with resonance self-shielding calculated using the RABBLE treatment. The results of the analyses are generally consistent with results obtained by other investigators. (auth)« less
Symmetry breaking in the opinion dynamics of a multi-group project organization
NASA Astrophysics Data System (ADS)
Zhu, Zhen-Tao; Zhou, Jing; Li, Ping; Chen, Xing-Guang
2012-10-01
A bounded confidence model of opinion dynamics in multi-group projects is presented in which each group's opinion evolution is driven by two types of forces: (i) the group's cohesive force which tends to restore the opinion back towards the initial status because of its company culture; and (ii) nonlinear coupling forces with other groups which attempt to bring opinions closer due to collaboration willingness. Bifurcation analysis for the case of a two-group project shows a cusp catastrophe phenomenon and three distinctive evolutionary regimes, i.e., a deadlock regime, a convergence regime, and a bifurcation regime in opinion dynamics. The critical value of initial discord between the two groups is derived to discriminate which regime the opinion evolution belongs to. In the case of a three-group project with a symmetric social network, both bifurcation analysis and simulation results demonstrate that if each pair has a high initial discord, instead of symmetrically converging to consensus with the increase of coupling scale as expected by Gabbay's result (Physica A 378 (2007) p. 125 Fig. 5), project organization (PO) may be split into two distinct clusters because of the symmetry breaking phenomenon caused by pitchfork bifurcations, which urges that apart from divergence in participants' interests, nonlinear interaction can also make conflict inevitable in the PO. The effects of two asymmetric level parameters are tested in order to explore the ways of inducing dominant opinion in the whole PO. It is found that the strong influence imposed by a leader group with firm faith on the flexible and open minded follower groups can promote the formation of a positive dominant opinion in the PO.
Evaluation of the Pool Critical Assembly Benchmark with Explicitly-Modeled Geometry using MCNP6
Kulesza, Joel A.; Martz, Roger Lee
2017-03-01
Despite being one of the most widely used benchmarks for qualifying light water reactor (LWR) radiation transport methods and data, no benchmark calculation of the Oak Ridge National Laboratory (ORNL) Pool Critical Assembly (PCA) pressure vessel wall benchmark facility (PVWBF) using MCNP6 with explicitly modeled core geometry exists. As such, this paper provides results for such an analysis. First, a criticality calculation is used to construct the fixed source term. Next, ADVANTG-generated variance reduction parameters are used within the final MCNP6 fixed source calculations. These calculations provide unadjusted dosimetry results using three sets of dosimetry reaction cross sections of varyingmore » ages (those packaged with MCNP6, from the IRDF-2002 multi-group library, and from the ACE-formatted IRDFF v1.05 library). These results are then compared to two different sets of measured reaction rates. The comparison agrees in an overall sense within 2% and on a specific reaction- and dosimetry location-basis within 5%. Except for the neptunium dosimetry, the individual foil raw calculation-to-experiment comparisons usually agree within 10% but is typically greater than unity. Finally, in the course of developing these calculations, geometry that has previously not been completely specified is provided herein for the convenience of future analysts.« less
Multigroup SIR epidemic model with stochastic perturbation
NASA Astrophysics Data System (ADS)
Ji, Chunyan; Jiang, Daqing; Shi, Ningzhong
2011-05-01
In this paper, we discuss a multigroup SIR model with stochastic perturbation. We deduce the globally asymptotic stability of the disease-free equilibrium when R0≤1, which means the disease will die out. On the other hand, when R0>1, we derive the disease will prevail, which is measured through the difference between the solution and the endemic equilibrium of the deterministic model in time average. Furthermore, we prove the system is persistent in the mean which also reflects the disease will prevail. The key to our analysis is choosing appropriate Lyapunov functions. Finally, we illustrate the dynamic behavior of the model with n=2 and their approximations via a range of numerical experiments.
Pachter, Lee M.; Auinger, Peggy; Palmer, Ray; Weitzman, Michael
2006-01-01
OBJECTIVE To determine whether the processes through which parenting practices, maternal depression, neighborhood, and chronic poverty affect child behavioral problems are similar or different in minority and nonminority children in the United States. METHODS Data from 884 white, 538 black, and 404 Latino families with children who were 6 to 9 years of age in the National Longitudinal Survey of Youth were analyzed. The outcome, child behavioral problems, was measured using the Behavior Problems Index externalizing and internalizing subscales. The effects of chronic poverty, neighborhood, maternal depression, and parenting on the outcome were analyzed using multigroup structural equation modeling. RESULTS Chronic poverty affected child behavioral problems indirectly through the other variables, and parenting practices had direct effects in each racial/ethnic group. The effects of maternal depression were partially mediated through parenting in the white and Latino samples but were direct and unmediated through parenting practices in the black sample. Neighborhood effects were present in the white and black samples but were not significant for the Latino sample. CONCLUSIONS Chronic poverty, neighborhood, maternal depression, and parenting practices have effects on child behavioral problems in white, black, and Latino children, but the processes and mechanisms through which they exert their effects differ among the groups. The differences may be related to social stratification mechanisms as well as sociocultural differences in family and childrearing practices. PMID:16585331
Asymptotic, multigroup flux reconstruction and consistent discontinuity factors
Trahan, Travis J.; Larsen, Edward W.
2015-05-12
Recent theoretical work has led to an asymptotically derived expression for reconstructing the neutron flux from lattice functions and multigroup diffusion solutions. The leading-order asymptotic term is the standard expression for flux reconstruction, i.e., it is the product of a shape function, obtained through a lattice calculation, and the multigroup diffusion solution. The first-order asymptotic correction term is significant only where the gradient of the diffusion solution is not small. Inclusion of this first-order correction term can significantly improve the accuracy of the reconstructed flux. One may define discontinuity factors (DFs) to make certain angular moments of the reconstructed fluxmore » continuous across interfaces between assemblies in 1-D. Indeed, the standard assembly discontinuity factors make the zeroth moment (scalar flux) of the reconstructed flux continuous. The inclusion of the correction term in the flux reconstruction provides an additional degree of freedom that can be used to make two angular moments of the reconstructed flux continuous across interfaces by using current DFs in addition to flux DFs. Thus, numerical results demonstrate that using flux and current DFs together can be more accurate than using only flux DFs, and that making the second angular moment continuous can be more accurate than making the zeroth moment continuous.« less
Model Comparison for Electron Thermal Transport
NASA Astrophysics Data System (ADS)
Moses, Gregory; Chenhall, Jeffrey; Cao, Duc; Delettrez, Jacques
2015-11-01
Four electron thermal transport models are compared for their ability to accurately and efficiently model non-local behavior in ICF simulations. Goncharov's transport model has accurately predicted shock timing in implosion simulations but is computationally slow and limited to 1D. The iSNB (implicit Schurtz Nicolai Busquet electron thermal transport method of Cao et al. uses multigroup diffusion to speed up the calculation. Chenhall has expanded upon the iSNB diffusion model to a higher order simplified P3 approximation and a Monte Carlo transport model, to bridge the gap between the iSNB and Goncharov models while maintaining computational efficiency. Comparisons of the above models for several test problems will be presented. This work was supported by Sandia National Laboratory - Albuquerque and the University of Rochester Laboratory for Laser Energetics.
Bøe, Tormod; Hysing, Mari; Skogen, Jens Christoffer; Breivik, Kyrre
2016-01-01
Although frequently used with older adolescents, few studies of the factor structure, internal consistency and gender equivalence of the SDQ exists for this age group, with inconsistent findings. In the present study, confirmatory factor analysis (CFA) was used to evaluate the five-factor structure of the SDQ in a population sample of 10,254 16-18 year-olds from the youth@hordaland study. Measurement invariance across gender was assessed using multigroup CFA. A modestly modified five-factor solution fitted the data acceptably, accounting for one cross loading and some local dependencies. Importantly, partial measurement non-invariance was identified, with differential item functioning in eight items, and higher correlations between emotional and conduct problems for boys compared to girls. Implications for use clinically and in research are discussed.
Jensen, Maria Therese; Rundmo, Torbjørn
2015-02-01
The aim of the study was to examine the associations among work-family conflict (WFC), emotional exhaustion, musculoskeletal (MS) pain, and gastrointestinal problems on a sample of business travelers (n = 2,093). An additional aim was to examine differences in the mentioned relationships among three traveler groups: commuters, national travelers, and international travelers. The study was conducted in a large Norwegian oil and gas company, and the company's business travel database was utilized to examine business travel. Structural equation modeling (SEM) revealed significant relations between WFC and emotional exhaustion and between emotional exhaustion and health problems. Contrary to the expectations, no direct association was found between WFC and health problems. However, we found that emotional exhaustion mediated the relation between WFC and health outcomes. The results from multi-group analysis revealed that associations among WFC, emotional exhaustion, and health-outcomes showed a similar pattern for commuters, national travelers, and international travelers. However, the association between emotional exhaustion and MS pain proved to be significantly stronger for the commuter group compared to the national and international travel groups. Practical implications and the consequences of these findings for future research are discussed. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.
Observed Parenting Behavior with Teens: Measurement Invariance and Predictive Validity Across Race
Skinner, Martie L.; MacKenzie, Elizabeth P.; Haggerty, Kevin P.; Hill, Karl G.; Roberson, Kendra C.
2011-01-01
Previous reports supporting measurement equality between European American and African American families have often focused on self-reported risk factors or observed parent behavior with young children. This study examines equality of measurement of observer ratings of parenting behavior with adolescents during structured tasks; mean levels of observed parenting; and predictive validity of teen self-reports of antisocial behaviors and beliefs using a sample of 163 African American and 168 European American families. Multiple-group confirmatory factor analyses supported measurement invariance across ethnic groups for 4 measures of observed parenting behavior: prosocial rewards, psychological costs, antisocial rewards, and problem solving. Some mean-level differences were found: African American parents exhibited lower levels of prosocial rewards, higher levels of psychological costs, and lower problem solving when compared to European Americans. No significant mean difference was found in rewards for antisocial behavior. Multigroup structural equation models suggested comparable relationships across race (predictive validity) between parenting constructs and youth antisocial constructs (i.e., drug initiation, positive drug attitudes, antisocial attitudes, problem behaviors) in all but one of the tested relationships. This study adds to existing evidence that family-based interventions targeting parenting behaviors can be generalized to African American families. PMID:21787057
Personality moderates the links of social identity with work motivation and job searching.
Baay, Pieter E; van Aken, Marcel A G; van der Lippe, Tanja; de Ridder, Denise T D
2014-01-01
Work motivation is critical for successful school-to-work transitions, but little is known about its determinants among labor market entrants. Applying a social identity framework, we examined whether work motivation and job searching are social-contextually determined. We expected that some job seekers are more sensitive to contextual influence, depending on their personality. Mediation analyses on 591 Dutch vocational training students indicate that the perception of more positive work norms in someone's social context was related to higher levels of intrinsic motivation, which in turn predicted higher preparatory job search behavior and job search intentions. Multi-group analysis shows that perceived work norms more strongly predict work motivation among overcontrollers compared to resilients and undercontrollers. In conclusion, work motivation and job searching appear contextually determined: especially among those sensitive to contextual influence, people seem to work when they believe that is what people like them do.
Perfetti, Christopher M.; Rearden, Bradley T.
2016-03-01
The sensitivity and uncertainty analysis tools of the ORNL SCALE nuclear modeling and simulation code system that have been developed over the last decade have proven indispensable for numerous application and design studies for nuclear criticality safety and reactor physics. SCALE contains tools for analyzing the uncertainty in the eigenvalue of critical systems, but cannot quantify uncertainty in important neutronic parameters such as multigroup cross sections, fuel fission rates, activation rates, and neutron fluence rates with realistic three-dimensional Monte Carlo simulations. A more complete understanding of the sources of uncertainty in these design-limiting parameters could lead to improvements in processmore » optimization, reactor safety, and help inform regulators when setting operational safety margins. A novel approach for calculating eigenvalue sensitivity coefficients, known as the CLUTCH method, was recently explored as academic research and has been found to accurately and rapidly calculate sensitivity coefficients in criticality safety applications. The work presented here describes a new method, known as the GEAR-MC method, which extends the CLUTCH theory for calculating eigenvalue sensitivity coefficients to enable sensitivity coefficient calculations and uncertainty analysis for a generalized set of neutronic responses using high-fidelity continuous-energy Monte Carlo calculations. Here, several criticality safety systems were examined to demonstrate proof of principle for the GEAR-MC method, and GEAR-MC was seen to produce response sensitivity coefficients that agreed well with reference direct perturbation sensitivity coefficients.« less
On the use of Bayesian Monte-Carlo in evaluation of nuclear data
NASA Astrophysics Data System (ADS)
De Saint Jean, Cyrille; Archier, Pascal; Privas, Edwin; Noguere, Gilles
2017-09-01
As model parameters, necessary ingredients of theoretical models, are not always predicted by theory, a formal mathematical framework associated to the evaluation work is needed to obtain the best set of parameters (resonance parameters, optical models, fission barrier, average width, multigroup cross sections) with Bayesian statistical inference by comparing theory to experiment. The formal rule related to this methodology is to estimate the posterior density probability function of a set of parameters by solving an equation of the following type: pdf(posterior) ˜ pdf(prior) × a likelihood function. A fitting procedure can be seen as an estimation of the posterior density probability of a set of parameters (referred as x→?) knowing a prior information on these parameters and a likelihood which gives the probability density function of observing a data set knowing x→?. To solve this problem, two major paths could be taken: add approximations and hypothesis and obtain an equation to be solved numerically (minimum of a cost function or Generalized least Square method, referred as GLS) or use Monte-Carlo sampling of all prior distributions and estimate the final posterior distribution. Monte Carlo methods are natural solution for Bayesian inference problems. They avoid approximations (existing in traditional adjustment procedure based on chi-square minimization) and propose alternative in the choice of probability density distribution for priors and likelihoods. This paper will propose the use of what we are calling Bayesian Monte Carlo (referred as BMC in the rest of the manuscript) in the whole energy range from thermal, resonance and continuum range for all nuclear reaction models at these energies. Algorithms will be presented based on Monte-Carlo sampling and Markov chain. The objectives of BMC are to propose a reference calculation for validating the GLS calculations and approximations, to test probability density distributions effects and to provide the framework of finding global minimum if several local minimums exist. Application to resolved resonance, unresolved resonance and continuum evaluation as well as multigroup cross section data assimilation will be presented.
Lifestyle choices and mental health: a longitudinal survey with German and Chinese students.
Velten, Julia; Bieda, Angela; Scholten, Saskia; Wannemüller, André; Margraf, Jürgen
2018-05-16
A healthy lifestyle can be beneficial for one's mental health. Thus, identifying healthy lifestyle choices that promote psychological well-being and reduce mental problems is useful to prevent mental disorders. The aim of this longitudinal study was to evaluate the predictive values of a broad range of lifestyle choices for positive mental health (PMH) and mental health problems (MHP) in German and Chinese students. Data were assessed at baseline and at 1-year follow-up. Samples included 2991 German (M age = 21.69, SD = 4.07) and 12,405 Chinese (M age = 20.59, SD = 1.58) university students. Lifestyle choices were body mass index, frequency of physical and mental activities, frequency of alcohol consumption, smoking, vegetarian diet, and social rhythm irregularity. PMH and MHP were measured with the Positive Mental Health Scale and a 21-item version of the Depression Anxiety and Stress Scale. The predictive values of lifestyle choices for PMH and MHP at baseline and follow-up were assessed with single-group and multi-group path analyses. Better mental health (higher PMH and fewer MHP) at baseline was predicted by a lower body mass index, a higher frequency of physical and mental activities, non-smoking, a non-vegetarian diet, and a more regular social rhythm. When controlling for baseline mental health, age, and gender, physical activity was a positive predictor of PMH, smoking was a positive predictor of MHP, and a more irregular social rhythm was a positive predictor of PMH and a negative predictor of MHP at follow-up. The good fit of a multi-group model indicated that most lifestyle choices predict mental health comparably across samples. Some country-specific effects emerged: frequency of alcohol consumption, for example, predicted better mental health in German and poorer mental health in Chinese students. Our findings underline the importance of healthy lifestyle choices for improved psychological well-being and fewer mental health difficulties. Effects of lifestyle on mental health are comparable in German and Chinese students. Some healthy lifestyle choices (i.e., more frequent physical activity, non-smoking, regular social rhythm) are related to improvements in mental health over a 1-year period.
Khafi, Tamar Y.; Yates, Tuppett M.; Sher-Censor, Efrat
2015-01-01
Emotional Overinvolvement (EOI) in parents’ Five Minute Speech Samples (FMSS; Magaña-Amato, 1993) is thought to measure overconcern and enmeshment with one’s child. Although related to maladaptive outcomes in studies of adult children, FMSS-EOI evidences varied relations with behavior problems in studies with young children. These mixed findings may indicate that certain FMSS-EOI criteria reflect inappropriate and excessive involvement with adult children, but do not indicate maladaptive processes when parenting younger children. Thus, this study evaluated relations of each FMSS-EOI criterion with changes in child behavior problems from preschool to first grade in a community sample of 223 child-mother dyads (47.98% female; Mage_W1 = 49.08 months; 56.50% Hispanic/Latina). Maternal FMSS-EOI ratings were obtained at wave 1, and independent examiners rated child externalizing and internalizing behavior problems at wave 1 and two years later. Path analyses indicated that both the Self-Sacrifice/Overprotection (SSOP) and Statements of Attitude (SOAs) FMSS-EOI criteria predicted increased externalizing problems. In contrast, Excessive Detail and Exaggerated Praise were not related to child externalizing behavior problems, and Emotional Display was not evident in this sample. None of the FMSS-EOI criteria evidenced significant relations with internalizing behavior problems. Multigroup comparisons indicated that the effect of SOAs on externalizing behavior problems was significant for boys but not for girls, and there were no significant group differences by race/ethnicity. These findings point to the salience of SSOP and SOAs for understanding the developmental significance of EOI in early development. PMID:26147935
NASA Astrophysics Data System (ADS)
Müller, Bernhard; Melson, Tobias; Heger, Alexander; Janka, Hans-Thomas
2017-11-01
We study the impact of large-scale perturbations from convective shell burning on the core-collapse supernova explosion mechanism using 3D multigroup neutrino hydrodynamics simulations of an 18M⊙ progenitor. Seed asphericities in the O shell, obtained from a recent 3D model of O shell burning, help trigger a neutrino-driven explosion 330 ms after bounce whereas the shock is not revived in a model based on a spherically symmetric progenitor for at least another 300 ms. We tentatively infer a reduction of the critical luminosity for shock revival by ˜ 20 {per cent} due to pre-collapse perturbations. This indicates that convective seed perturbations play an important role in the explosion mechanism in some progenitors. We follow the evolution of the 18M⊙ model into the explosion phase for more than 2 s and find that the cycle of accretion and mass ejection is still ongoing at this stage. With a preliminary value of 7.7 × 1050 erg for the diagnostic explosion energy, a baryonic neutron star mass of 1.85M⊙, a neutron star kick of ˜ 600 km s^{-1} and a neutron star spin period of ˜ 20 ms at the end of the simulation, the explosion and remnant properties are slightly atypical, but still lie comfortably within the observed distribution. Although more refined simulations and a larger survey of progenitors are still called for, this suggests that a solution to the problem of shock revival and explosion energies in the ballpark of observations is within reach for neutrino-driven explosions in 3D.
A Comparison of Monte Carlo and Deterministic Solvers for keff and Sensitivity Calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Haeck, Wim; Parsons, Donald Kent; White, Morgan Curtis
Verification and validation of our solutions for calculating the neutron reactivity for nuclear materials is a key issue to address for many applications, including criticality safety, research reactors, power reactors, and nuclear security. Neutronics codes solve variations of the Boltzmann transport equation. The two main variants are Monte Carlo versus deterministic solutions, e.g. the MCNP [1] versus PARTISN [2] codes, respectively. There have been many studies over the decades that examined the accuracy of such solvers and the general conclusion is that when the problems are well-posed, either solver can produce accurate results. However, the devil is always in themore » details. The current study examines the issue of self-shielding and the stress it puts on deterministic solvers. Most Monte Carlo neutronics codes use continuous-energy descriptions of the neutron interaction data that are not subject to this effect. The issue of self-shielding occurs because of the discretisation of data used by the deterministic solutions. Multigroup data used in these solvers are the average cross section and scattering parameters over an energy range. Resonances in cross sections can occur that change the likelihood of interaction by one to three orders of magnitude over a small energy range. Self-shielding is the numerical effect that the average cross section in groups with strong resonances can be strongly affected as neutrons within that material are preferentially absorbed or scattered out of the resonance energies. This affects both the average cross section and the scattering matrix.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collins, Benjamin S.; Hamilton, Steven P.; Stimpson, Shane
The development of VERA-CS in recent years has focused on developing the capability to simulate multiple cycles of operating commercial nuclear power plants. Now that these capabilities have advanced to the point where it is being deployed to users, the focus is on improving the computational performance of various components in VERA-CS. In this work, the focus is on the Coarse Mesh Finite Difference (CMFD) solution in MPACT. CMFD serves multiple purposes in the 2D/1D solution methodology. First, it is a natural mechanism to tie together the radial MOC transport and the axial SP3 solution. Because the CMFD system solvesmore » the multigroup three-dimensional core in one system, it pulls together the global response of the system. In addition, the CMFD solution provides a framework to accelerate the convergence of the eigenvalue problem.« less
Hysing, Mari; Skogen, Jens Christoffer; Breivik, Kyrre
2016-01-01
Although frequently used with older adolescents, few studies of the factor structure, internal consistency and gender equivalence of the SDQ exists for this age group, with inconsistent findings. In the present study, confirmatory factor analysis (CFA) was used to evaluate the five-factor structure of the SDQ in a population sample of 10,254 16–18 year-olds from the youth@hordaland study. Measurement invariance across gender was assessed using multigroup CFA. A modestly modified five-factor solution fitted the data acceptably, accounting for one cross loading and some local dependencies. Importantly, partial measurement non-invariance was identified, with differential item functioning in eight items, and higher correlations between emotional and conduct problems for boys compared to girls. Implications for use clinically and in research are discussed. PMID:27138259
Multi-Group Maximum Entropy Model for Translational Non-Equilibrium
NASA Technical Reports Server (NTRS)
Jayaraman, Vegnesh; Liu, Yen; Panesi, Marco
2017-01-01
The aim of the current work is to describe a new model for flows in translational non- equilibrium. Starting from the statistical description of a gas proposed by Boltzmann, the model relies on a domain decomposition technique in velocity space. Using the maximum entropy principle, the logarithm of the distribution function in each velocity sub-domain (group) is expressed with a power series in molecular velocity. New governing equations are obtained using the method of weighted residuals by taking the velocity moments of the Boltzmann equation. The model is applied to a spatially homogeneous Boltzmann equation with a Bhatnagar-Gross-Krook1(BGK) model collision operator and the relaxation of an initial non-equilibrium distribution to a Maxwellian is studied using the model. In addition, numerical results obtained using the model for a 1D shock tube problem are also reported.
Automatic variance reduction for Monte Carlo simulations via the local importance function transform
DOE Office of Scientific and Technical Information (OSTI.GOV)
Turner, S.A.
1996-02-01
The author derives a transformed transport problem that can be solved theoretically by analog Monte Carlo with zero variance. However, the Monte Carlo simulation of this transformed problem cannot be implemented in practice, so he develops a method for approximating it. The approximation to the zero variance method consists of replacing the continuous adjoint transport solution in the transformed transport problem by a piecewise continuous approximation containing local biasing parameters obtained from a deterministic calculation. He uses the transport and collision processes of the transformed problem to bias distance-to-collision and selection of post-collision energy groups and trajectories in a traditionalmore » Monte Carlo simulation of ``real`` particles. He refers to the resulting variance reduction method as the Local Importance Function Transform (LIFI) method. He demonstrates the efficiency of the LIFT method for several 3-D, linearly anisotropic scattering, one-group, and multigroup problems. In these problems the LIFT method is shown to be more efficient than the AVATAR scheme, which is one of the best variance reduction techniques currently available in a state-of-the-art Monte Carlo code. For most of the problems considered, the LIFT method produces higher figures of merit than AVATAR, even when the LIFT method is used as a ``black box``. There are some problems that cause trouble for most variance reduction techniques, and the LIFT method is no exception. For example, the author demonstrates that problems with voids, or low density regions, can cause a reduction in the efficiency of the LIFT method. However, the LIFT method still performs better than survival biasing and AVATAR in these difficult cases.« less
Analyzing average and conditional effects with multigroup multilevel structural equation models
Mayer, Axel; Nagengast, Benjamin; Fletcher, John; Steyer, Rolf
2014-01-01
Conventionally, multilevel analysis of covariance (ML-ANCOVA) has been the recommended approach for analyzing treatment effects in quasi-experimental multilevel designs with treatment application at the cluster-level. In this paper, we introduce the generalized ML-ANCOVA with linear effect functions that identifies average and conditional treatment effects in the presence of treatment-covariate interactions. We show how the generalized ML-ANCOVA model can be estimated with multigroup multilevel structural equation models that offer considerable advantages compared to traditional ML-ANCOVA. The proposed model takes into account measurement error in the covariates, sampling error in contextual covariates, treatment-covariate interactions, and stochastic predictors. We illustrate the implementation of ML-ANCOVA with an example from educational effectiveness research where we estimate average and conditional effects of early transition to secondary schooling on reading comprehension. PMID:24795668
An Automatic Detection System of Lung Nodule Based on Multi-Group Patch-Based Deep Learning Network.
Jiang, Hongyang; Ma, He; Qian, Wei; Gao, Mengdi; Li, Yan
2017-07-14
High-efficiency lung nodule detection dramatically contributes to the risk assessment of lung cancer. It is a significant and challenging task to quickly locate the exact positions of lung nodules. Extensive work has been done by researchers around this domain for approximately two decades. However, previous computer aided detection (CADe) schemes are mostly intricate and time-consuming since they may require more image processing modules, such as the computed tomography (CT) image transformation, the lung nodule segmentation and the feature extraction, to construct a whole CADe system. It is difficult for those schemes to process and analyze enormous data when the medical images continue to increase. Besides, some state of the art deep learning schemes may be strict in the standard of database. This study proposes an effective lung nodule detection scheme based on multi-group patches cut out from the lung images, which are enhanced by the Frangi filter. Through combining two groups of images, a four-channel convolution neural networks (CNN) model is designed to learn the knowledge of radiologists for detecting nodules of four levels. This CADe scheme can acquire the sensitivity of 80.06% with 4.7 false positives per scan and the sensitivity of 94% with 15.1 false positives per scan. The results demonstrate that the multi-group patch-based learning system is efficient to improve the performance of lung nodule detection and greatly reduce the false positives under a huge amount of image data.
Schnettler, Berta; Miranda, Horacio; Miranda-Zapata, Edgardo; Salinas-Oñate, Natalia; Grunert, Klaus G; Lobos, Germán; Sepúlveda, José; Orellana, Ligia; Hueche, Clementina; Bonilla, Héctor
2017-06-01
This study examined longitudinal measurement invariance in the Satisfaction with Food-related Life (SWFL) scale using follow-up data from university students. We examined this measure of the SWFL in different groups of students, separated by various characteristics. Through non-probabilistic longitudinal sampling, 114 university students (65.8% female, mean age: 22.5) completed the SWFL questionnaire three times, over intervals of approximately one year. Confirmatory factor analysis was used to examine longitudinal measurement invariance. Two types of analysis were conducted: first, a longitudinal invariance by time, and second, a multigroup longitudinal invariance by sex, age, socio-economic status and place of residence during the study period. Results showed that the 3-item version of the SWFL exhibited strong longitudinal invariance (equal factor loadings and equal indicator intercepts). Longitudinal multigroup invariance analysis also showed that the 3-item version of the SWFL displays strong invariance by socio-economic status and place of residence during the study period over time. Nevertheless, it was only possible to demonstrate equivalence of the longitudinal factor structure among students of both sexes, and among those older and younger than 22 years. Generally, these findings suggest that the SWFL scale has satisfactory psychometric properties for longitudinal measurement invariance in university students with similar characteristics as the students that participated in this research. It is also possible to suggest that satisfaction with food-related life is associated with sex and age. Copyright © 2017 Elsevier Ltd. All rights reserved.
Giordano, R; Passarella, G; Uricchio, V F; Vurro, M
2007-07-01
The importance of shared decision processes in water management derives from the awareness of the inadequacy of traditional--i.e. engineering--approaches in dealing with complex and ill-structured problems. It is becoming increasingly obvious that traditional problem solving and decision support techniques, based on optimisation and factual knowledge, have to be combined with stakeholder based policy design and implementation. The aim of our research is the definition of an integrated decision support system for consensus achievement (IDSS-C) able to support a participative decision-making process in all its phases: problem definition and structuring, identification of the possible alternatives, formulation of participants' judgments, and consensus achievement. Furthermore, the IDSS-C aims at structuring, i.e. systematising the knowledge which has emerged during the participative process in order to make it comprehensible for the decision-makers and functional for the decision process. Problem structuring methods (PSM) and multi-group evaluation methods (MEM) have been integrated in the IDSS-C. PSM are used to support the stakeholders in providing their perspective of the problem and to elicit their interests and preferences, while MEM are used to define not only the degree of consensus for each alternative, highlighting those where the agreement is high, but also the consensus label for each alternative and the behaviour of individuals during the participative decision-making. The IDSS-C is applied experimentally to a decision process regarding the use of treated wastewater for agricultural irrigation in the Apulia Region (southern Italy).
Hybrid parallel code acceleration methods in full-core reactor physics calculations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Courau, T.; Plagne, L.; Ponicot, A.
2012-07-01
When dealing with nuclear reactor calculation schemes, the need for three dimensional (3D) transport-based reference solutions is essential for both validation and optimization purposes. Considering a benchmark problem, this work investigates the potential of discrete ordinates (Sn) transport methods applied to 3D pressurized water reactor (PWR) full-core calculations. First, the benchmark problem is described. It involves a pin-by-pin description of a 3D PWR first core, and uses a 8-group cross-section library prepared with the DRAGON cell code. Then, a convergence analysis is performed using the PENTRAN parallel Sn Cartesian code. It discusses the spatial refinement and the associated angular quadraturemore » required to properly describe the problem physics. It also shows that initializing the Sn solution with the EDF SPN solver COCAGNE reduces the number of iterations required to converge by nearly a factor of 6. Using a best estimate model, PENTRAN results are then compared to multigroup Monte Carlo results obtained with the MCNP5 code. Good consistency is observed between the two methods (Sn and Monte Carlo), with discrepancies that are less than 25 pcm for the k{sub eff}, and less than 2.1% and 1.6% for the flux at the pin-cell level and for the pin-power distribution, respectively. (authors)« less
Deterministic methods for multi-control fuel loading optimization
NASA Astrophysics Data System (ADS)
Rahman, Fariz B. Abdul
We have developed a multi-control fuel loading optimization code for pressurized water reactors based on deterministic methods. The objective is to flatten the fuel burnup profile, which maximizes overall energy production. The optimal control problem is formulated using the method of Lagrange multipliers and the direct adjoining approach for treatment of the inequality power peaking constraint. The optimality conditions are derived for a multi-dimensional multi-group optimal control problem via calculus of variations. Due to the Hamiltonian having a linear control, our optimal control problem is solved using the gradient method to minimize the Hamiltonian and a Newton step formulation to obtain the optimal control. We are able to satisfy the power peaking constraint during depletion with the control at beginning of cycle (BOC) by building the proper burnup path forward in time and utilizing the adjoint burnup to propagate the information back to the BOC. Our test results show that we are able to achieve our objective and satisfy the power peaking constraint during depletion using either the fissile enrichment or burnable poison as the control. Our fuel loading designs show an increase of 7.8 equivalent full power days (EFPDs) in cycle length compared with 517.4 EFPDs for the AP600 first cycle.
Zohsel, K; Bianchi, V; Mascheretti, S; Hohm, E; Schmidt, M H; Esser, G; Brandeis, D; Banaschewski, T; Nobile, M; Laucht, M
2015-11-01
Attention problems affect a substantial number of children and adolescents and are predictive of academic underachievement and lower global adaptive functioning. Considerable variability has been observed with regard to the individual development of attention problems over time. In particular, the period of adolescence is characterized by substantial maturation of executive functioning including attentional processing, with the influence of genetic and environmental factors on individual trajectories not yet well understood. In the present investigation, we evaluated whether the monoamine oxidase A functional promoter polymorphism, MAOA-LPR, plays a role in determining continuity of parent-rated attention problems during adolescence. At the same time, a potential effect of severe life events (SLEs) was taken into account. A multi-group path analysis was used in a sample of 234 adolescents (149 males, 85 females) who took part in an epidemiological cohort study at the ages of 11 and 15 years. Attention problems during early adolescence were found to be a strong predictor of attention problems in middle adolescence. However, in carriers of the MAOA-LPR low-activity variant (MAOA-L), stability was found to be significantly higher than in carriers of the high-activity variant (MAOA-H). Additionally, only in MAOA-L carriers did SLEs during adolescence significantly impact on attention problems at the age of 15 years, implying a possible gene × environment interaction. To conclude, we found evidence that attention problems during adolescence in carriers of the MAOA-L allele are particularly stable and malleable to life stressors. The present results underline the usefulness of applying a more dynamic GxE perspective. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.
Automated variance reduction for MCNP using deterministic methods.
Sweezy, J; Brown, F; Booth, T; Chiaramonte, J; Preeg, B
2005-01-01
In order to reduce the user's time and the computer time needed to solve deep penetration problems, an automated variance reduction capability has been developed for the MCNP Monte Carlo transport code. This new variance reduction capability developed for MCNP5 employs the PARTISN multigroup discrete ordinates code to generate mesh-based weight windows. The technique of using deterministic methods to generate importance maps has been widely used to increase the efficiency of deep penetration Monte Carlo calculations. The application of this method in MCNP uses the existing mesh-based weight window feature to translate the MCNP geometry into geometry suitable for PARTISN. The adjoint flux, which is calculated with PARTISN, is used to generate mesh-based weight windows for MCNP. Additionally, the MCNP source energy spectrum can be biased based on the adjoint energy spectrum at the source location. This method can also use angle-dependent weight windows.
Heinze, Justin E; Cook, Stephanie H; Wood, Erica P; Dumadag, Anne C; Zimmerman, Marc A
2018-01-01
Exposure to violence during adolescence is associated with increased risk behaviors and mental health problems in adulthood. Friendship attachment during adolescence may, however, mitigate the negative effects of exposure to violence on trajectories of depression and anxiety in young adulthood. In this study, we used growth curve modeling to examine associations between exposure to violence and mental health outcomes, followed by multi-group analyses with friendship attachment as the moderator. The sample was drawn from a longitudinal study (12 waves; 1994-2012) of 676 (54% female) urban high school students. We found strong positive associations between exposure to violence during adolescence and later self-reported depressive and anxiety symptoms. Notably, securely attached adolescents reported faster decreases in mental health symptoms as a function of violence relative to their insecurely attached peers as they transitioned into adulthood.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tommasi, J.; Ruggieri, J. M.; Lebrat, J. F.
The latest release (2.1) of the ERANOS code system, using JEF-2.2, JEFF-3.1 and ENDF/B-VI r8 multigroup cross-section libraries is currently being validated on fast reactor critical experiments at CEA-Cadarache (France). This paper briefly presents the library effect studies and the detailed best-estimate validation studies performed up to now as part of the validation process. The library effect studies are performed over a wide range of experimental configurations, using simple model and method options. They yield global trends about the shift from JEF-2.2 to JEFF-3.1 cross-section libraries, that can be related to individual sensitivities and cross-section changes. The more detailed, best-estimate,more » calculations have been performed up to now over three experimental configurations carried out in the MASURCA critical facility at CEA-Cadarache: two cores with a softened spectrum due to large amounts of graphite (MAS1A' and MAS1B), and a core representative of sodium-cooled fast reactors (CIRANO ZONA2A). Calculated values have been compared to measurements, and discrepancies analyzed in detail using perturbation theory. Values calculated with JEFF-3.1 were found to be within 3 standard deviations of the measured values, and at least of the same quality as the JEF-2.2 based results. (authors)« less
ANALYSIS OF THE MOMENTS METHOD EXPERIMENT
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kloster, R.L.
1959-09-01
Monte Cario calculations show the effects of a plane water-air boundary on both fast neutron and gamma dose rates. Multigroup diffusion theory calculation for a reactor source shows the effects of a plane water-air boundary on thermal neutron dose rate. The results of Monte Cario and multigroup calculations are compared with experimental values. The predicted boundary effect for fast neutrons of 7.3% agrees within 16% with the measured effect of 6.3%. The gamma detector did not measure a boundary effect because it lacked sensitivity at low energies. However, the effect predicted for gamma rays of 5 to 10% is asmore » large as that for neutrons. An estimate of the boundary effect for thermal neutrons from a PoBe source is obtained from the results of muitigroup diffusion theory calcuiations for a reactor source. The calculated boundary effect agrees within 13% with the measured values. (auth)« less
Multigroup Monte Carlo on GPUs: Comparison of history- and event-based algorithms
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamilton, Steven P.; Slattery, Stuart R.; Evans, Thomas M.
This article presents an investigation of the performance of different multigroup Monte Carlo transport algorithms on GPUs with a discussion of both history-based and event-based approaches. Several algorithmic improvements are introduced for both approaches. By modifying the history-based algorithm that is traditionally favored in CPU-based MC codes to occasionally filter out dead particles to reduce thread divergence, performance exceeds that of either the pure history-based or event-based approaches. The impacts of several algorithmic choices are discussed, including performance studies on Kepler and Pascal generation NVIDIA GPUs for fixed source and eigenvalue calculations. Single-device performance equivalent to 20–40 CPU cores onmore » the K40 GPU and 60–80 CPU cores on the P100 GPU is achieved. Last, in addition, nearly perfect multi-device parallel weak scaling is demonstrated on more than 16,000 nodes of the Titan supercomputer.« less
Multigroup Monte Carlo on GPUs: Comparison of history- and event-based algorithms
Hamilton, Steven P.; Slattery, Stuart R.; Evans, Thomas M.
2017-12-22
This article presents an investigation of the performance of different multigroup Monte Carlo transport algorithms on GPUs with a discussion of both history-based and event-based approaches. Several algorithmic improvements are introduced for both approaches. By modifying the history-based algorithm that is traditionally favored in CPU-based MC codes to occasionally filter out dead particles to reduce thread divergence, performance exceeds that of either the pure history-based or event-based approaches. The impacts of several algorithmic choices are discussed, including performance studies on Kepler and Pascal generation NVIDIA GPUs for fixed source and eigenvalue calculations. Single-device performance equivalent to 20–40 CPU cores onmore » the K40 GPU and 60–80 CPU cores on the P100 GPU is achieved. Last, in addition, nearly perfect multi-device parallel weak scaling is demonstrated on more than 16,000 nodes of the Titan supercomputer.« less
ATDM Rover Milestone Report STDA02-1 (FY2017 Q4)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Larsen, Matt; Laney, Dan E.
We have successfully completed the MS-4/Y1 Milestone STDA02-1 for the Rover Project. This document describes the milestone and provides an overview of the technical details and artifacts of the milestone. This milestone is focused on building a GPU accelerated ray tracing package capable of doing multi-group radiography, both back-lit and with self-emission as well as serving as a volume rendering plot in VisIt and other VTK-based visualization tools. The long term goal is a package with in-situ capability, but for this first version integration into VisIt is the primary goal. Milestone Execution Plan: Create API for GPU Raytracer that supportsmore » multi-group transport (up to hundreds of groups); Implement components into one or more of: VTK-m, VisIt, and a new library/package implementation to be hosted on LLNL Bitbucket (initially), before releasing to the wider community.« less
Further development of the talent development environment questionnaire for sport.
Li, Chunxiao; Wang, Chee Keng John; Pyun, Do Young; Martindale, Russell
2015-01-01
Given the significance of monitoring the critical environmental factors that facilitate athlete performance, this two-phase research aimed to validate and refine the revised talent development environment questionnaire (TDEQ). The TDEQ is a multidimensional self-report scale that assesses talented athletes' environmental experiences. Study 1 (the first phase) involved the examination of the revised TDEQ through an exploratory factor analysis (n = 363). This exploratory investigation identified a 28-item five-factor structure (i.e., TDEQ-5) with adequate internal consistency. Study 2 (the second phase) examined the factorial structure of the TDEQ-5, including convergent validity, discriminant validity, and group invariance (i.e., gender and sports type). The second phase was carried out with 496 talented athletes through the application of confirmatory factor analyses and multigroup invariance tests. The results supported the convergent validity, discriminant validity, and group invariance of the TDEQ-5. In conclusion, the TDEQ-5 with 25 items appears to be a reliable and valid scale for use in talent development environments.
Best, Alicia L; Alcaraz, Kassandra I; McQueen, Amy; Cooper, Dexter L; Warren, Rueben C; Stein, Kevin
2015-09-01
African American (AA) cancer survivors report poorer self-rated health (SRH) compared to other racial/ethnic groups. Spirituality is often linked to positive health outcomes, with AAs reporting greater levels of spirituality. This study examined the potential mediating role of cancer-related problems in the relationship between spirituality and SRH among AA cancer survivors compared to non-African American (non-AA) survivors. We analyzed data on 9006 adult cancer survivors from the American Cancer Society's Study of Cancer Survivors-II. Preliminary analyses compared characteristics of AAs and non-AAs and identified significant covariates of SRH. We tested a path model using multi-group structural equation modeling (SEM), and then examined race as a moderator. Of the three domains of spirituality assessed, AAs had higher levels of peace (p < .001) and faith (p < .001), but not meaning, compared to non-AAs; and of four domains of cancer-related problems assessed, AAs had greater physical distress (p < .001), emotional distress (p < .001), and employment/finance problems (p < .001), but not fear of recurrence. In SEM analyses adjusting for number of comorbidities and income, race moderated the impact of spirituality and cancer-related problems on SRH. Specifically, spirituality had significantly stronger associations with cancer-related problems among AAs than non-AAs. Spirituality was positively associated with all four domains of cancer-related problems, but only physical distress was associated with SRH among AAs. The negative effects of physical distress may attenuate the positive effects of spirituality on AA's SRH. Future studies should consider racial/ethnic differences in the determinants and conceptualization of SRH, which is a known predictor of survival. Copyright © 2014 John Wiley & Sons, Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Risner, J. M.; Wiarda, D.; Dunn, M. E.
2011-09-30
New coupled neutron-gamma cross-section libraries have been developed for use in light water reactor (LWR) shielding applications, including pressure vessel dosimetry calculations. The libraries, which were generated using Evaluated Nuclear Data File/B Version VII Release 0 (ENDF/B-VII.0), use the same fine-group and broad-group energy structures as the VITAMIN-B6 and BUGLE-96 libraries. The processing methodology used to generate both libraries is based on the methods used to develop VITAMIN-B6 and BUGLE-96 and is consistent with ANSI/ANS 6.1.2. The ENDF data were first processed into the fine-group pseudo-problem-independent VITAMIN-B7 library and then collapsed into the broad-group BUGLE-B7 library. The VITAMIN-B7 library containsmore » data for 391 nuclides. This represents a significant increase compared to the VITAMIN-B6 library, which contained data for 120 nuclides. The BUGLE-B7 library contains data for the same nuclides as BUGLE-96, and maintains the same numeric IDs for those nuclides. The broad-group data includes nuclides which are infinitely dilute and group collapsed using a concrete weighting spectrum, as well as nuclides which are self-shielded and group collapsed using weighting spectra representative of important regions of LWRs. The verification and validation of the new libraries includes a set of critical benchmark experiments, a set of regression tests that are used to evaluate multigroup crosssection libraries in the SCALE code system, and three pressure vessel dosimetry benchmarks. Results of these tests confirm that the new libraries are appropriate for use in LWR shielding analyses and meet the requirements of Regulatory Guide 1.190.« less
Comparison of actinide production in traveling wave and pressurized water reactors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Osborne, A.G.; Smith, T.A.; Deinert, M.R.
The geopolitical problems associated with civilian nuclear energy production arise in part from the accumulation of transuranics in spent nuclear fuel. A traveling wave reactor is a type of breed-burn reactor that could, if feasible, reduce the overall production of transuranics. In one possible configuration, a cylinder of natural or depleted uranium would be subjected to a fast neutron flux at one end. The neutrons would transmute the uranium, producing plutonium and higher actinides. Under the right conditions, the reactor could become critical, at which point a self-stabilizing fission wave would form and propagate down the length of the reactormore » cylinder. The neutrons from the fission wave would burn the fissile nuclides and transmute uranium ahead of the wave to produce additional fuel. Fission waves in uranium are driven largely by the production and fission of {sup 239}Pu. Simulations have shown that the fuel burnup can reach values greater than 400 MWd/kgIHM, before fission products poison the reaction. In this work we compare the production of plutonium and minor actinides produced in a fission wave to that of a UOX fueled light water reactor, both on an energy normalized basis. The nuclide concentrations in the spent traveling wave reactor fuel are computed using a one-group diffusion model and are verified using Monte Carlo simulations. In the case of the pressurized water reactor, a multi-group collision probability model is used to generate the nuclide quantities. We find that the traveling wave reactor produces about 0.187 g/MWd/kgIHM of transuranics compared to 0.413 g/MWd/kgIHM for a pressurized water reactor running fuel enriched to 4.95 % and burned to 50 MWd/kgIHM. (authors)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hernandez-Solis, A.; Demaziere, C.; Ekberg, C.
2012-07-01
In this paper, multi-group microscopic cross-section uncertainty is propagated through the DRAGON (Version 4) lattice code, in order to perform uncertainty analysis on k{infinity} and 2-group homogenized macroscopic cross-sections predictions. A statistical methodology is employed for such purposes, where cross-sections of certain isotopes of various elements belonging to the 172 groups DRAGLIB library format, are considered as normal random variables. This library is based on JENDL-4 data, because JENDL-4 contains the largest amount of isotopic covariance matrixes among the different major nuclear data libraries. The aim is to propagate multi-group nuclide uncertainty by running the DRAGONv4 code 500 times, andmore » to assess the output uncertainty of a test case corresponding to a 17 x 17 PWR fuel assembly segment without poison. The chosen sampling strategy for the current study is Latin Hypercube Sampling (LHS). The quasi-random LHS allows a much better coverage of the input uncertainties than simple random sampling (SRS) because it densely stratifies across the range of each input probability distribution. Output uncertainty assessment is based on the tolerance limits concept, where the sample formed by the code calculations infers to cover 95% of the output population with at least a 95% of confidence. This analysis is the first attempt to propagate parameter uncertainties of modern multi-group libraries, which are used to feed advanced lattice codes that perform state of the art resonant self-shielding calculations such as DRAGONv4. (authors)« less
Gifford, Kent A; Wareing, Todd A; Failla, Gregory; Horton, John L; Eifel, Patricia J; Mourtada, Firas
2009-12-03
A patient dose distribution was calculated by a 3D multi-group S N particle transport code for intracavitary brachytherapy of the cervix uteri and compared to previously published Monte Carlo results. A Cs-137 LDR intracavitary brachytherapy CT data set was chosen from our clinical database. MCNPX version 2.5.c, was used to calculate the dose distribution. A 3D multi-group S N particle transport code, Attila version 6.1.1 was used to simulate the same patient. Each patient applicator was built in SolidWorks, a mechanical design package, and then assembled with a coordinate transformation and rotation for the patient. The SolidWorks exported applicator geometry was imported into Attila for calculation. Dose matrices were overlaid on the patient CT data set. Dose volume histograms and point doses were compared. The MCNPX calculation required 14.8 hours, whereas the Attila calculation required 22.2 minutes on a 1.8 GHz AMD Opteron CPU. Agreement between Attila and MCNPX dose calculations at the ICRU 38 points was within +/- 3%. Calculated doses to the 2 cc and 5 cc volumes of highest dose differed by not more than +/- 1.1% between the two codes. Dose and DVH overlays agreed well qualitatively. Attila can calculate dose accurately and efficiently for this Cs-137 CT-based patient geometry. Our data showed that a three-group cross-section set is adequate for Cs-137 computations. Future work is aimed at implementing an optimized version of Attila for radiotherapy calculations.
Development and validation of the alcohol Expectancy Questionnaire Short Form (EQ-SF).
Mezquita, Laura; Camacho, Laura; Suso-Ribera, Carlos; Ortet, Generós; Ibáñez, Manuel I
2018-01-15
Alcohol expectancies are proximal variables to alcohol use and misuse. In recent decades, different measures have been developed to assess this construct. One of the most frequently used and recommended instruments is the Expectancy Questionnaire (EQ; Leigh y Stacy, 1993). Our aim is to develop a short version of the EQ (EQ-SF) for suitable use in time-limited administrations. Two samples, adolescents (N = 514, 57.20% females) and adults (N = 548, 61.50% females), completed the EQ together with alcohol-use measures. Different item selection strategies were applied to select the 24 items. The EQ-SF structure was explored using confirmatory factor analysis, and measurement invariance was tested running a multi-group analysis comparing groups by sex and age. Reliability was tested using Cronbach's alpha and omega coefficients. Concurrent validity was investigated with regression analyses. The EQ-SF showed acceptable between-groups measurement invariance. Alphas and omegas ranged from .77 to .93. Positive expectancies predicted both alcohol use and alcohol-related problems. Negative expectancies predicted alcohol-related problems. Sex and age moderated these associations. Males with high positive alcohol expectancies showed higher alcohol consumption than females, while adults with high negative alcohol expectancies showed greater alcohol-related problems than adolescents. Different evidence on the validity and reliability of the EQ-SF suggest that it is a suitable instrument to assess alcohol expectancies in the Spanish population.
Racial-Ethnic Identity and Adjustment in Canadian Indigenous Adolescents
ERIC Educational Resources Information Center
Gfellner, Barbara M.; Armstrong, Helen D.
2013-01-01
This study supported associations between three theoretically driven conceptualizations of racial and ethnic identity (REI; Multigroup Ethnic Identity Measure; Multidimensional Racial Identity Measure; Bicultural Identity Measure) and with adaptive functioning among Canadian indigenous adolescents in middle school to high school. Age differences…
The Multigroup Multilevel Categorical Latent Growth Curve Models
ERIC Educational Resources Information Center
Hung, Lai-Fa
2010-01-01
Longitudinal data describe developmental patterns and enable predictions of individual changes beyond sampled time points. Major methodological issues in longitudinal data include modeling random effects, subject effects, growth curve parameters, and autoregressive residuals. This study embedded the longitudinal model within a multigroup…
2016-10-01
Reports an error in "Reliability Generalization of the Multigroup Ethnic Identity Measure-Revised (MEIM-R)" by Hayley M. Herrington, Timothy B. Smith, Erika Feinauer and Derek Griner ( Journal of Counseling Psychology , Advanced Online Publication, Mar 17, 2016, np). The name of author Erika Feinauer was misspelled as Erika Feinhauer. All versions of this article have been corrected. (The following abstract of the original article appeared in record 2016-13160-001.) Individuals' strength of ethnic identity has been linked with multiple positive indicators, including academic achievement and overall psychological well-being. The measure researchers use most often to assess ethnic identity, the Multigroup Ethnic Identity Measure (MEIM), underwent substantial revision in 2007. To inform scholars investigating ethnic identity, we performed a reliability generalization analysis on data from the revised version (MEIM-R) and compared it with data from the original MEIM. Random-effects weighted models evaluated internal consistency coefficients (Cronbach's alpha). Reliability coefficients for the MEIM-R averaged α = .88 across 37 samples, a statistically significant increase over the average of α = .84 for the MEIM across 75 studies. Reliability coefficients for the MEIM-R did not differ across study and participant characteristics such as sample gender and ethnic composition. However, consistently lower reliability coefficients averaging α = .81 were found among participants with low levels of education, suggesting that greater attention to data reliability is warranted when evaluating the ethnic identity of individuals such as middle-school students. Future research will be needed to ascertain whether data with other measures of aspects of personal identity (e.g., racial identity, gender identity) also differ as a function of participant level of education and associated cognitive or maturation processes. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Wu, Tzu-Yi; Lin, Chung-Ying; Årestedt, Kristofer; Griffiths, Mark D.; Broström, Anders; Pakpour, Amir H.
2017-01-01
Background and aims The nine-item Internet Gaming Disorder Scale – Short Form (IGDS-SF9) is brief and effective to evaluate Internet Gaming Disorder (IGD) severity. Although its scores show promising psychometric properties, less is known about whether different groups of gamers interpret the items similarly. This study aimed to verify the construct validity of the Persian IGDS-SF9 and examine the scores in relation to gender and hours spent online gaming among 2,363 Iranian adolescents. Methods Confirmatory factor analysis (CFA) and Rasch analysis were used to examine the construct validity of the IGDS-SF9. The effects of gender and time spent online gaming per week were investigated by multigroup CFA and Rasch differential item functioning (DIF). Results The unidimensionality of the IGDS-SF9 was supported in both CFA and Rasch. However, Item 4 (fail to control or cease gaming activities) displayed DIF (DIF contrast = 0.55) slightly over the recommended cutoff in Rasch but was invariant in multigroup CFA across gender. Items 4 (DIF contrast = −0.67) and 9 (jeopardize or lose an important thing because of gaming activity; DIF contrast = 0.61) displayed DIF in Rasch and were non-invariant in multigroup CFA across time spent online gaming. Conclusions Given the Persian IGDS-SF9 was unidimensional, it is concluded that the instrument can be used to assess IGD severity. However, users of the instrument are cautioned concerning the comparisons of the sum scores of the IGDS-SF9 across gender and across adolescents spending different amounts of time online gaming. PMID:28571474
Wu, Tzu-Yi; Lin, Chung-Ying; Årestedt, Kristofer; Griffiths, Mark D; Broström, Anders; Pakpour, Amir H
2017-06-01
Background and aims The nine-item Internet Gaming Disorder Scale - Short Form (IGDS-SF9) is brief and effective to evaluate Internet Gaming Disorder (IGD) severity. Although its scores show promising psychometric properties, less is known about whether different groups of gamers interpret the items similarly. This study aimed to verify the construct validity of the Persian IGDS-SF9 and examine the scores in relation to gender and hours spent online gaming among 2,363 Iranian adolescents. Methods Confirmatory factor analysis (CFA) and Rasch analysis were used to examine the construct validity of the IGDS-SF9. The effects of gender and time spent online gaming per week were investigated by multigroup CFA and Rasch differential item functioning (DIF). Results The unidimensionality of the IGDS-SF9 was supported in both CFA and Rasch. However, Item 4 (fail to control or cease gaming activities) displayed DIF (DIF contrast = 0.55) slightly over the recommended cutoff in Rasch but was invariant in multigroup CFA across gender. Items 4 (DIF contrast = -0.67) and 9 (jeopardize or lose an important thing because of gaming activity; DIF contrast = 0.61) displayed DIF in Rasch and were non-invariant in multigroup CFA across time spent online gaming. Conclusions Given the Persian IGDS-SF9 was unidimensional, it is concluded that the instrument can be used to assess IGD severity. However, users of the instrument are cautioned concerning the comparisons of the sum scores of the IGDS-SF9 across gender and across adolescents spending different amounts of time online gaming.
Geiser, Christian; Griffin, Daniel; Shiffman, Saul
2016-01-01
Sometimes, researchers are interested in whether an intervention, experimental manipulation, or other treatment causes changes in intra-individual state variability. The authors show how multigroup-multiphase latent state-trait (MG-MP-LST) models can be used to examine treatment effects with regard to both mean differences and differences in state variability. The approach is illustrated based on a randomized controlled trial in which N = 338 smokers were randomly assigned to nicotine replacement therapy (NRT) vs. placebo prior to quitting smoking. We found that post quitting, smokers in both the NRT and placebo group had significantly reduced intra-individual affect state variability with respect to the affect items calm and content relative to the pre-quitting phase. This reduction in state variability did not differ between the NRT and placebo groups, indicating that quitting smoking may lead to a stabilization of individuals' affect states regardless of whether or not individuals receive NRT.
Geiser, Christian; Griffin, Daniel; Shiffman, Saul
2016-01-01
Sometimes, researchers are interested in whether an intervention, experimental manipulation, or other treatment causes changes in intra-individual state variability. The authors show how multigroup-multiphase latent state-trait (MG-MP-LST) models can be used to examine treatment effects with regard to both mean differences and differences in state variability. The approach is illustrated based on a randomized controlled trial in which N = 338 smokers were randomly assigned to nicotine replacement therapy (NRT) vs. placebo prior to quitting smoking. We found that post quitting, smokers in both the NRT and placebo group had significantly reduced intra-individual affect state variability with respect to the affect items calm and content relative to the pre-quitting phase. This reduction in state variability did not differ between the NRT and placebo groups, indicating that quitting smoking may lead to a stabilization of individuals' affect states regardless of whether or not individuals receive NRT. PMID:27499744
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greene, N.M.; Ford, W.E. III; Petrie, L.M.
AMPX-77 is a modular system of computer programs that pertain to nuclear analyses, with a primary emphasis on tasks associated with the production and use of multigroup cross sections. AH basic cross-section data are to be input in the formats used by the Evaluated Nuclear Data Files (ENDF/B), and output can be obtained in a variety of formats, including its own internal and very general formats, along with a variety of other useful formats used by major transport, diffusion theory, and Monte Carlo codes. Processing is provided for both neutron and gamma-my data. The present release contains codes all writtenmore » in the FORTRAN-77 dialect of FORTRAN and wig process ENDF/B-V and earlier evaluations, though major modules are being upgraded in order to process ENDF/B-VI and will be released when a complete collection of usable routines is available.« less
Tang, Wenming; Liu, Guixiong; Li, Yuzhong; Tan, Daji
2017-01-01
High data transmission efficiency is a key requirement for an ultrasonic phased array with multi-group ultrasonic sensors. Here, a novel FIFOs scheduling algorithm was proposed and the data transmission efficiency with hardware technology was improved. This algorithm includes FIFOs as caches for the ultrasonic scanning data obtained from the sensors with the output data in a bandwidth-sharing way, on the basis of which an optimal length ratio of all the FIFOs is achieved, allowing the reading operations to be switched among all the FIFOs without time slot waiting. Therefore, this algorithm enhances the utilization ratio of the reading bandwidth resources so as to obtain higher efficiency than the traditional scheduling algorithms. The reliability and validity of the algorithm are substantiated after its implementation in the field programmable gate array (FPGA) technology, and the bandwidth utilization ratio and the real-time performance of the ultrasonic phased array are enhanced. PMID:29035345
Using Structural Equation Modeling To Fit Models Incorporating Principal Components.
ERIC Educational Resources Information Center
Dolan, Conor; Bechger, Timo; Molenaar, Peter
1999-01-01
Considers models incorporating principal components from the perspectives of structural-equation modeling. These models include the following: (1) the principal-component analysis of patterned matrices; (2) multiple analysis of variance based on principal components; and (3) multigroup principal-components analysis. Discusses fitting these models…
Group Counseling for African American Elementary Students: An Exploratory Study
ERIC Educational Resources Information Center
Steen, Sam
2009-01-01
This article describes a group counseling intervention promoting academic achievement and ethnic identity development for twenty fifth grade African American elementary students. The Multigroup Ethnic Identity Measure (MEIM) scores of students participating in the treatment group improved significantly over those in the control group. Implications…
A Multigroup Investigation of Latent Cognitive Abilities and Reading Achievement Relations
ERIC Educational Resources Information Center
Hajovsky, Daniel; Reynolds, Matthew R.; Floyd, Randy G.; Turek, Joshua J.; Keith, Timothy Z.
2014-01-01
The structural relations between the Cattell-Horn-Carroll abilities and reading achievement outcome variables across child and adolescent development were examined in the "Kaufman Assessment Battery for Children, Second Edition", and the "Kaufman Test of Educational Achievement, Second Edition", co-normed sample. We estimated…
Toward the Style of the Community Change Educator.
ERIC Educational Resources Information Center
Franklin, Richard
Variations and implications of change agents' patterns or styles of interaction with client systems (individuals, groups, or multigroups) are discussed. Five styles are defined: (1) the instructor, who imparts information to clients and interacts only with his agency; (2) the paterfamilias, who exercises personal, paternalistic influence and…
Talley, Amelia E.; Aranda, Frances; Hughes, Tonda L.; Everett, Bethany; Johnson, Timothy P.
2015-01-01
We examined differences between sexual minority women’s (SMW’s) sexual identity and sexual behavior or sexual attraction as potential contributors to hazardous drinking across a 10-year period. Data are from a longitudinal study examining drinking and drinking-related problems in a diverse, community-based sample of self-identified SMW (Wave 1: n = 447; Wave 2: n = 384; Wave 3: n = 354). Longitudinal cross-lagged models showed that SMW who report higher levels of identity-behavior or identity-attraction discordance may be at greater risk of concurrent and subsequent hazardous drinking. Results of multigroup models suggest that sexual orientation discordance is a more potent risk factor for risky drinking outcomes among SMW in older adulthood than in younger adulthood. Findings support that discordance between sexual orientation dimensions may contribute to hazardous drinking among SMW and provide evidence that cognitive-behavioral consistency is important for individuals expressing diverse and fluid sexual identities, attraction, and behavior. PMID:25911224
Valdez, Carmen R.; Shewakramani, Vansa; Goldberg, Simon; Padilla, Brian
2013-01-01
Although it is widely accepted that parental depression is associated with problems with children’s socioemotional adjustment, the pathways by which parental depression influences children’s adjustment, particularly in low-income Latino children are not fully understood. In our investigation of 1,462 low-income Latino children in the first grade and their Spanish- and English-dominant parents, a factor analysis revealed three main pathways of possible influence of parent involvement in children’s social development: emotional involvement and educational involvement at home and at school. The findings from multigroup structural equation modeling revealed that whereas the first two pathways mediated the effect of parental depression on child social competence for Spanish-dominant parents, only emotional involvement explained parental depression effects for English-dominant parents. Parent educational involvement at school did not mediate parental depression effects for either Spanish- or English-dominant Latino parents. Discussion and implications of findings with respect to research, practice, and policy with Latinos follow. PMID:23325021
Valdez, Carmen R; Shewakramani, Vansa; Goldberg, Simon; Padilla, Brian
2013-10-01
Although it is widely accepted that parental depression is associated with problems with children's socioemotional adjustment, the pathways by which parental depression influences children's adjustment, particularly in low-income Latino children are not fully understood. In our investigation of 1,462 low-income Latino children in the first grade and their Spanish- and English-dominant parents, a factor analysis revealed three main pathways of possible influence of parent involvement in children's social development: emotional involvement and educational involvement at home and at school. The findings from multigroup structural equation modeling revealed that whereas the first two pathways mediated the effect of parental depression on child social competence for Spanish-dominant parents, only emotional involvement explained parental depression effects for English-dominant parents. Parent educational involvement at school did not mediate parental depression effects for either Spanish- or English-dominant Latino parents. Discussion and implications of findings with respect to research, practice, and policy with Latinos follow.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wollaeger, Ryan T.; Van Rossum, Daniel R., E-mail: wollaeger@wisc.edu, E-mail: daan@flash.uchicago.edu
Implicit Monte Carlo (IMC) and Discrete Diffusion Monte Carlo (DDMC) are methods used to stochastically solve the radiative transport and diffusion equations, respectively. These methods combine into a hybrid transport-diffusion method we refer to as IMC-DDMC. We explore a multigroup IMC-DDMC scheme that in DDMC, combines frequency groups with sufficient optical thickness. We term this procedure ''opacity regrouping''. Opacity regrouping has previously been applied to IMC-DDMC calculations for problems in which the dependence of the opacity on frequency is monotonic. We generalize opacity regrouping to non-contiguous groups and implement this in SuperNu, a code designed to do radiation transport inmore » high-velocity outflows with non-monotonic opacities. We find that regrouping of non-contiguous opacity groups generally improves the speed of IMC-DDMC radiation transport. We present an asymptotic analysis that informs the nature of the Doppler shift in DDMC groups and summarize the derivation of the Gentile-Fleck factor for modified IMC-DDMC. We test SuperNu using numerical experiments including a quasi-manufactured analytic solution, a simple 10 group problem, and the W7 problem for Type Ia supernovae. We find that opacity regrouping is necessary to make our IMC-DDMC implementation feasible for the W7 problem and possibly Type Ia supernova simulations in general. We compare the bolometric light curves and spectra produced by the SuperNu and PHOENIX radiation transport codes for the W7 problem. The overall shape of the bolometric light curves are in good agreement, as are the spectra and their evolution with time. However, for the numerical specifications we considered, we find that the peak luminosity of the light curve calculated using SuperNu is ∼10% less than that calculated using PHOENIX.« less
Radiation Transport for Explosive Outflows: Opacity Regrouping
NASA Astrophysics Data System (ADS)
Wollaeger, Ryan T.; van Rossum, Daniel R.
2014-10-01
Implicit Monte Carlo (IMC) and Discrete Diffusion Monte Carlo (DDMC) are methods used to stochastically solve the radiative transport and diffusion equations, respectively. These methods combine into a hybrid transport-diffusion method we refer to as IMC-DDMC. We explore a multigroup IMC-DDMC scheme that in DDMC, combines frequency groups with sufficient optical thickness. We term this procedure "opacity regrouping." Opacity regrouping has previously been applied to IMC-DDMC calculations for problems in which the dependence of the opacity on frequency is monotonic. We generalize opacity regrouping to non-contiguous groups and implement this in SuperNu, a code designed to do radiation transport in high-velocity outflows with non-monotonic opacities. We find that regrouping of non-contiguous opacity groups generally improves the speed of IMC-DDMC radiation transport. We present an asymptotic analysis that informs the nature of the Doppler shift in DDMC groups and summarize the derivation of the Gentile-Fleck factor for modified IMC-DDMC. We test SuperNu using numerical experiments including a quasi-manufactured analytic solution, a simple 10 group problem, and the W7 problem for Type Ia supernovae. We find that opacity regrouping is necessary to make our IMC-DDMC implementation feasible for the W7 problem and possibly Type Ia supernova simulations in general. We compare the bolometric light curves and spectra produced by the SuperNu and PHOENIX radiation transport codes for the W7 problem. The overall shape of the bolometric light curves are in good agreement, as are the spectra and their evolution with time. However, for the numerical specifications we considered, we find that the peak luminosity of the light curve calculated using SuperNu is ~10% less than that calculated using PHOENIX.
Eigenvalue Solvers for Modeling Nuclear Reactors on Leadership Class Machines
Slaybaugh, R. N.; Ramirez-Zweiger, M.; Pandya, Tara; ...
2018-02-20
In this paper, three complementary methods have been implemented in the code Denovo that accelerate neutral particle transport calculations with methods that use leadership-class computers fully and effectively: a multigroup block (MG) Krylov solver, a Rayleigh quotient iteration (RQI) eigenvalue solver, and a multigrid in energy (MGE) preconditioner. The MG Krylov solver converges more quickly than Gauss Seidel and enables energy decomposition such that Denovo can scale to hundreds of thousands of cores. RQI should converge in fewer iterations than power iteration (PI) for large and challenging problems. RQI creates shifted systems that would not be tractable without the MGmore » Krylov solver. It also creates ill-conditioned matrices. The MGE preconditioner reduces iteration count significantly when used with RQI and takes advantage of the new energy decomposition such that it can scale efficiently. Each individual method has been described before, but this is the first time they have been demonstrated to work together effectively. The combination of solvers enables the RQI eigenvalue solver to work better than the other available solvers for large reactors problems on leadership-class machines. Using these methods together, RQI converged in fewer iterations and in less time than PI for a full pressurized water reactor core. These solvers also performed better than an Arnoldi eigenvalue solver for a reactor benchmark problem when energy decomposition is needed. The MG Krylov, MGE preconditioner, and RQI solver combination also scales well in energy. Finally, this solver set is a strong choice for very large and challenging problems.« less
Eigenvalue Solvers for Modeling Nuclear Reactors on Leadership Class Machines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slaybaugh, R. N.; Ramirez-Zweiger, M.; Pandya, Tara
In this paper, three complementary methods have been implemented in the code Denovo that accelerate neutral particle transport calculations with methods that use leadership-class computers fully and effectively: a multigroup block (MG) Krylov solver, a Rayleigh quotient iteration (RQI) eigenvalue solver, and a multigrid in energy (MGE) preconditioner. The MG Krylov solver converges more quickly than Gauss Seidel and enables energy decomposition such that Denovo can scale to hundreds of thousands of cores. RQI should converge in fewer iterations than power iteration (PI) for large and challenging problems. RQI creates shifted systems that would not be tractable without the MGmore » Krylov solver. It also creates ill-conditioned matrices. The MGE preconditioner reduces iteration count significantly when used with RQI and takes advantage of the new energy decomposition such that it can scale efficiently. Each individual method has been described before, but this is the first time they have been demonstrated to work together effectively. The combination of solvers enables the RQI eigenvalue solver to work better than the other available solvers for large reactors problems on leadership-class machines. Using these methods together, RQI converged in fewer iterations and in less time than PI for a full pressurized water reactor core. These solvers also performed better than an Arnoldi eigenvalue solver for a reactor benchmark problem when energy decomposition is needed. The MG Krylov, MGE preconditioner, and RQI solver combination also scales well in energy. Finally, this solver set is a strong choice for very large and challenging problems.« less
Predictors of Satisfaction in Geographically Close and Long-Distance Relationships
ERIC Educational Resources Information Center
Lee, Ji-yeon; Pistole, M. Carole
2012-01-01
In this study, the authors examined geographically close (GCRs) and long-distance (LDRs) romantic relationship satisfaction as explained by insecure attachment, self-disclosure, gossip, and idealization. After college student participants (N = 536) completed a Web survey, structural equation modeling (SEM) multigroup analysis revealed that the GCR…
Treatment Effects for Adolescent Struggling Readers: An Application of Moderated Mediation
ERIC Educational Resources Information Center
Roberts, Greg; Fletcher, Jack M.; Stuebing, Karla K.; Barth, Amy E.; Vaughn, Sharon
2013-01-01
This study used multigroup structural equations to evaluate the possibility that a theory-driven, evidence-based, yearlong reading program for sixth-grade struggling readers moderates the interrelationships among elements of the simple model of reading (i.e., listening comprehension, word reading, and reading comprehension; Hoover & Gough,…
Toward a Model of Strategies and Summary Writing Performance
ERIC Educational Resources Information Center
Yang, Hui-Chun
2014-01-01
This study explores the construct of a summarization test task by means of single-group and multigroup structural equation modeling (SEM). It examines the interrelationships between strategy use and performance, drawing on data from 298 Taiwanese undergraduates' summary essays and their self-reported strategy use. Single-group SEM analyses…
An Investigation of Measurement Invariance across Genders on the Overexcitability Questionnaire-Two
ERIC Educational Resources Information Center
Warne, Russell T.
2011-01-01
The Overexcitability Questionnaire-Two (OEQII) is a quantitative instrument for assessing overexcitabilities as they are described in Dabrowski's theory of positive disintegration. This article uses multigroup confirmatory factor analysis to examine the measurement invariance of OEQII scores across genders. Results indicate that raw OEQII scores…
A REACTOR DESIGN PARAMETER STUDY
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, A.H.; LaVerne, M.E.; Burtnette, C.S.
1954-06-25
Multigroup calculations were performed on reflectormoderated systems to establish some of the nuclear characteristics of various reflector geometries and materials. C, Li/sup 7/, Li/sup 7/OD, and NaOD moderators were used with NaF-UF/ sub 4/ fuel. The results are tabulated for 57 moderator and dimensional variations. (D.E.B.)
Teachers' Engagement at Work: An International Validation Study
ERIC Educational Resources Information Center
Klassen, Robert M.; Aldhafri, Said; Mansfield, Caroline F.; Purwanto, Edy; Siu, Angela F. Y.; Wong, Marina W.; Woods-McConney, Amanda
2012-01-01
This study explored the validity of the Utrecht Work Engagement Scale in a sample of 853 practicing teachers from Australia, Canada, China (Hong Kong), Indonesia, and Oman. The authors used multigroup confirmatory factor analysis to test the factor structure and measurement invariance across settings, after which they examined the relationships…
Dimensions of Cultural Differences: Pancultural, ETIC/EMIC, and Ecological Approaches
ERIC Educational Resources Information Center
Stankov, Lazar; Lee, Jihyun
2009-01-01
We investigated the factorial structure of four major domains in social psychology (personality traits, social attitudes, values, and social norms) with an emphasis on cross-cultural differences. Three distinctive approaches--pancultural, multigroup, and multilevel--were applied to the data based on 22 measures that were collected from 2029…
An Examination of Statistical Power in Multigroup Dynamic Structural Equation Models
ERIC Educational Resources Information Center
Prindle, John J.; McArdle, John J.
2012-01-01
This study used statistical simulation to calculate differential statistical power in dynamic structural equation models with groups (as in McArdle & Prindle, 2008). Patterns of between-group differences were simulated to provide insight into how model parameters influence power approximations. Chi-square and root mean square error of…
The Structure of Cognitive Abilities in Youths with Manic Symptoms: A Factorial Invariance Study
ERIC Educational Resources Information Center
Beaujean, A. Alexander; Freeman, Megan Joseph; Youngstrom, Eric; Carlson, Gabrielle
2012-01-01
This study compared the structure of cognitive ability (specifically, verbal/crystallized ["Gc"] and visual-spatial ability ["Gv"]), as measured in the Wechsler Intelligence Scale for Children, in youth with manic symptoms with a nationally representative group of similarly aged youth. Multigroup confirmatory factor analysis…
Ethnic Identity and Career Development among First-Year College Students
ERIC Educational Resources Information Center
Duffy, Ryan D.; Klingaman, Elizabeth A.
2009-01-01
The current study explored the relation of ethnic identity achievement and career development progress among a sample of 2,432 first-year college students who completed the Career Decision Profile and Phinney's Multigroup Ethnic Identity Measure. Among students of color, correlational analyses revealed a series of statistically significant, but…
A Cross-Cultural Evaluation of Ethnic Identity Exploration and Commitment
ERIC Educational Resources Information Center
Mills, Sarah D.; Murray, Kate E.
2017-01-01
We evaluated the unique contribution of the two subscales of the Multigroup Ethnic Identity Measure-Revised (MEIM-R), Exploration and Commitment, to mental and behavioral health outcomes among non-Hispanic White, ethnic minority, and mixed-race college students. Monoracial ethnic minority and mixed-race students reported higher Exploration scores…
Writing and reading: connections between language by hand and language by eye.
Berninger, Virginia W; Abbott, Robert D; Abbott, Sylvia P; Graham, Steve; Richards, Todd
2002-01-01
Four approaches to the investigation of connections between language by hand and language by eye are described and illustrated with studies from a decade-long research program. In the first approach, multigroup structural equation modeling is applied to reading and writing measures given to typically developing writers to examine unidirectional and bidirectional relationships between specific components of the reading and writing systems. In the second approach, structural equation modeling is applied to a multivariate set of language measures given to children and adults with reading and writing disabilities to examine how the same set of language processes is orchestrated differently to accomplish specific reading or writing goals, and correlations between factors are evaluated to examine the level at which the language-by-hand system and the language-by-eye system communicate most easily. In the third approach, mode of instruction and mode of response are systematically varied in evaluating effectiveness of treating reading disability with and without a writing component. In the fourth approach, functional brain imaging is used to investigate residual spelling problems in students whose problems with word decoding have been remediated. The four approaches support a model in which language by hand and language by eye are separate systems that interact in predictable ways.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brodrick, Jonathan P.; Kingham, R. J.; Marinak, M. M.
Three models for nonlocal electron thermal transport are here compared against Vlasov-Fokker-Planck (VFP) codes to assess their accuracy in situations relevant to both inertial fusion hohlraums and tokamak scrape-off layers. The models tested are (i) a moment-based approach using an eigenvector integral closure (EIC) originally developed by Ji, Held, and Sovinec [Phys. Plasmas 16, 022312 (2009)]; (ii) the non-Fourier Landau-fluid (NFLF) model of Dimits, Joseph, and Umansky [Phys. Plasmas 21, 055907 (2014)]; and (iii) Schurtz, Nicolaï, and Busquet’s [Phys. Plasmas 7, 4238 (2000)] multigroup diffusion model (SNB). We find that while the EIC and NFLF models accurately predict the dampingmore » rate of a small-amplitude temperature perturbation (within 10% at moderate collisionalities), they overestimate the peak heat flow by as much as 35% and do not predict preheat in the more relevant case where there is a large temperature difference. The SNB model, however, agrees better with VFP results for the latter problem if care is taken with the definition of the mean free path. Additionally, we present for the first time a comparison of the SNB model against a VFP code for a hohlraum-relevant problem with inhomogeneous ionisation and show that the model overestimates the heat flow in the helium gas-fill by a factor of ~2 despite predicting the peak heat flux to within 16%.« less
Extension of the Bgl Broad Group Cross Section Library
NASA Astrophysics Data System (ADS)
Kirilova, Desislava; Belousov, Sergey; Ilieva, Krassimira
2009-08-01
The broad group cross-section libraries BUGLE and BGL are applied for reactor shielding calculation using the DOORS package based on discrete ordinates method and multigroup approximation of the neutron cross-sections. BUGLE and BGL libraries are problem oriented for PWR or VVER type of reactors respectively. They had been generated by collapsing the problem independent fine group library VITAMIN-B6 applying PWR and VVER one-dimensional radial model of the reactor middle plane using the SCALE software package. The surveillance assemblies (SA) of VVER-1000/320 are located on the baffle above the reactor core upper edge in a region where geometry and materials differ from those of the middle plane and the neutron field gradient is very high which would result in a different neutron spectrum. That is why the application of the fore-mentioned libraries for the neutron fluence calculation in the region of SA could lead to an additional inaccuracy. This was the main reason to study the necessity for an extension of the BGL library with cross-sections appropriate for the SA region. Comparative analysis of the neutron spectra of the SA region calculated by the VITAMIN-B6 and BGL libraries using the two-dimensional code DORT have been done with purpose to evaluate the BGL applicability for SA calculation.
Raskin, Maryna; Easterbrooks, M Ann; Lamoreau, Renee S; Kotake, Chie; Goldberg, Jessica
2016-01-01
This study explores the longitudinal trajectories of depressive symptoms in young mothers and investigate the consequences of maternal depression for children's birth outcomes and behavioral adjustment. Antenatal depression puts children of young mothers at risk for adjustment difficulties by adversely impacting birth outcomes and maternal symptoms after birth. Data were drawn from a three-wave randomized, controlled trial of a statewide home visiting program for young primiparous women. A subsample of women (n = 400) who were prenatal at intake was used in the analysis. Mothers were divided into an antenatally depressed group (ADG; 40%) and a healthy group (HG) based on their symptoms at intake. Mothers reported depressive symptoms at intake and 12- and 24-month follow-up, and filled out a checklist of child behavior problems at 24 months follow-up. Perinatal and birth outcomes were derived from the Electronic Birth Certificate collected by the State Department of Public Health at discharge from the hospital. ADG and HG had similar pregnancy characteristics and birth outcomes, but ADG reported more child behavioral problems. Multigroup latent growth curve analysis provided evidence for distinct depression trajectories. A mediation hypothesis was not supported. In both groups, steeper increase in symptoms over time predicted more mother-reported child behavioral problems. Findings are consistent with studies linking antenatal depression with post-birth symptoms, underscoring the importance of prenatal screening for depression. Copyright © 2016 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.
Core and peripheral criteria of video game addiction in the game addiction scale for adolescents.
Brunborg, Geir Scott; Hanss, Daniel; Mentzoni, Rune Aune; Pallesen, Ståle
2015-05-01
Assessment of video game addiction often involves measurement of peripheral criteria that indicate high engagement with games, and core criteria that indicate problematic use of games. A survey of the Norwegian population aged 16-74 years (N=10,081, response rate 43.6%) was carried out in 2013, which included the Gaming Addiction Scale for Adolescents (GAS). Confirmatory factor analysis showed that a two-factor structure, which separated peripheral criteria from core criteria, fitted the data better (CFI=0.963; RMSEA=0.058) compared to the original one-factor solution where all items are determined to load only on one factor (CFI=0.905, RMSEA=0.089). This was also found when we analyzed men aged ≤33 years, men aged >33 years, women aged ≤33 years, and women aged >33 years separately. This indicates that the GAS measures both engagement and problems related to video games. Multi-group measurement invariance testing showed that the factor structure was valid in all four groups (configural invariance) for the two-factor structure but not for the one-factor structure. A novel approach to categorization of problem gamers and addicted gamers where only the core criteria items are used (the CORE 4 approach) was compared to the approach where all items are included (the GAS 7 approach). The current results suggest that the CORE 4 approach might be more appropriate for classification of problem gamers and addicted gamers compared to the GAS 7 approach.
Enhanced Critical Thinking Skills through Problem-Solving Games in Secondary Schools
ERIC Educational Resources Information Center
McDonald, Scott Douglas
2017-01-01
Aim/Purpose: Students face many challenges improving their soft skills such as critical thinking. This paper offers one possible solution to this problem. Background: This paper considers one method of enhancing critical thinking through a problem-solving game called the Coffee Shop. Problem-solving is a key component to critical thinking, and…
Emotional Intelligence and Negative Feelings: A Gender Specific Moderated Mediation Model
ERIC Educational Resources Information Center
Karakus, Mehmet
2013-01-01
This study aims to clarify the effect of emotional intelligence (EI) on negative feelings (stress, anxiety, burnout and depression) in a gender specific model. Four hundred and twenty-five primary school teachers (326 males, 99 females) completed the measures of EI, stress, anxiety, burnout and depression. The multi-group analysis was performed…
Cultural Validation of the Maslach Burnout Inventory for Korean Students
ERIC Educational Resources Information Center
Shin, Hyojung; Puig, Ana; Lee, Jayoung; Lee, Ji Hee; Lee, Sang Min
2011-01-01
The purpose of this study was to examine the factorial validity of the MBI-SS in Korean students. Specifically, we investigated whether the original three-factor structure of the MBI-SS was appropriate for use with Korean students. In addition, by running multi-group structural equation model analyses with factorial invariance tests simultaneously…
Measuring Teaching Quality and Student Engagement in South Korea and The Netherlands
ERIC Educational Resources Information Center
van de Grift, Wim J. C. M.; Chun, Seyeoung; Maulana, Ridwan; Lee, Okhwa; Helms-Lorenz, Michelle
2017-01-01
Six observation scales for measuring the skills of teachers and 1 scale for measuring student engagement, assessed in South Korea and The Netherlands, are sufficiently reliable and offer sufficient predictive value for student engagement. A multigroup confirmatory factor analysis shows that the factor loadings and intercepts of the scales are the…
Exploring Student, Family, and School Predictors of Self-Determination Using NLTS2 Data
ERIC Educational Resources Information Center
Shogren, Karrie A.; Garnier Villarreal, Mauricio; Dowsett, Chantelle; Little, Todd D.
2016-01-01
This study conducted secondary analysis of data from the National Longitudinal Transition Study-2 (NLTS2) to examine the degree to which student, family, and school constructs predicted self-determination outcomes. Multi-group structural equation modeling was used to examine predictive relationships between 5 students, 4 family, and 7 school…
Exploring Student, Family, and School Predictors of Self-Determination Using NLTS2 Data
ERIC Educational Resources Information Center
Shogren, Karrie A.; Garnier Villarreal, Mauricio; Dowsett, Chantelle; Little, Todd D.
2016-01-01
This study conducted secondary analysis of data from the National Longitudinal Transition Study-2 (NLTS2) to examine the degree to which student, family, and school constructs predicted self-determination outcomes. Multi-group structural equation modeling was used to examine predictive relationships between 5 student, 4 family, and 7 school…
Systems of Goals, Attitudes, and Self-Related Beliefs in Second-Language-Learning Motivation
ERIC Educational Resources Information Center
Kormos, Judit; Kiddle, Thom; Csizer, Kata
2011-01-01
In the present study, we surveyed the English language-learning motivations of 518 secondary school students, university students, and young adult learners in the capital of Chile, Santiago. We applied multi-group structural-equation modeling to analyze how language-learning goals, attitudes, self-related beliefs, and parental encouragement…
Ethnic Identity and Civic Attitudes in Latino and Caucasian Youth
ERIC Educational Resources Information Center
Anglin, Ashley Elizabeth; Johnson-Pynn, Julie S.; Johnson, Laura Renee
2012-01-01
Understanding youth's perceptions of their civic skills is important for enriching the lives of youth as well as society. This study explored the relationship between civic attitudes, leadership skills, and ethnic identity in Northwest Georgia schools using two measures, the Civic Attitudes and Skills Questionnaire (CASQ) and the Multigroup Ethnic…
ERIC Educational Resources Information Center
Smith, Martin M.; Saklofske, Donald H.; Yan, Gonggu; Sherry, Simon B.
2016-01-01
This study investigated the generalizability of the tripartite model of perfectionism across Canadian and Chinese university students. Using latent profile analysis and indicators of perfectionistic strivings, perfectionistic concerns, and neuroticism in both groups, the authors derived a 3-profile solution: adaptive perfectionists, maladaptive…
Sex Differences in Adults' Motivation to Achieve
ERIC Educational Resources Information Center
van der Sluis, Sophie; Vinkhuyzen, Anna A. E.; Boomsma, Dorret I.; Posthuma, Danielle
2010-01-01
Achievement motivation is considered a prerequisite for success in academic as well as non-academic settings. We studied sex differences in academic and general achievement motivation in an adult sample of 338 men and 497 women (ages 18-70 years). Multi-group covariance and means structure analysis (MG-CMSA) for ordered categorical data was used…
The Importance of Multi-Group Validity Evidence in Gifted and Talented Identification and Research
ERIC Educational Resources Information Center
Peters, Scott J.
2011-01-01
Practitioners and researchers often review the validity evidence of an instrument before using it for student assessment or in the practice of diagnosing or identifying children with exceptionalities. However, few test manuals present data on instrument measurement equivalence/ invariance or differential item functioning. This information is…
ERIC Educational Resources Information Center
Brown, Gavin; Harris, Lois
2012-01-01
Student beliefs about assessment may vary according to the level of schooling. The "Students Conceptions of Assessment" version 6 (SCoA-VI) inventory elicits attitudes towards four beliefs (assessment: improves teaching and learning, measures external factors, has affective impact/benefit, is irrelevant). Using multi-group confirmatory…
ERIC Educational Resources Information Center
Su, Xiaoxia; McBride, Ron E.; Xiang, Ping
2015-01-01
The current study examined the measurement invariance across 361 male and female college students' 2 × 2 achievement goal orientation and motivational regulations. Participants completed questionnaires assessing their achievement goals and motivational regulations. Multigroup CFA analyses showed that male and female students' scores were fully…
Power and Precision in Confirmatory Factor Analytic Tests of Measurement Invariance
ERIC Educational Resources Information Center
Meade, Adam W.; Bauer, Daniel J.
2007-01-01
This study investigates the effects of sample size, factor overdetermination, and communality on the precision of factor loading estimates and the power of the likelihood ratio test of factorial invariance in multigroup confirmatory factor analysis. Although sample sizes are typically thought to be the primary determinant of precision and power,…
ERIC Educational Resources Information Center
Sun, Huaping; Hernandez, Diley
2012-01-01
This study investigates the structural invariance of the Achievement Goal Questionnaire (AGQ) in American, Chinese, and Dutch college students. Using confirmatory factor analyses (CFA), the authors found evidence for the four-factor structure of achievement goals in all three samples. Subsequent multigroup CFAs supported structural invariance of…
ERIC Educational Resources Information Center
Wu, Wenfeng; Lu, Yongbiao; Tan, Furong; Yao, Shuqiao; Steca, Patrizia; Abela, John R. Z.; Hankin, Benjamin L.
2012-01-01
This study tested the measurement invariance of Children's Depression Inventory (CDI) and compared its factorial variance/covariance and latent means among Chinese and Italian children. Multigroup confirmatory factor analysis of the original five factors identified by Kovacs revealed that full measurement invariance did not hold. Further analysis…
Moderators of Youth Exercise Intention and Behavior
ERIC Educational Resources Information Center
Ellis, Rebecca; Kosma, Maria; Symons Downs, Danielle
2013-01-01
This study tested moderators of the theory of planned behavior (TPB) based on geographical region, gender, race, and income among adolescents in an exercise context using multigroup path analyses. Participants were eighth- and ninth-grade students from Louisiana (LA; N = 448, M[subscript age] = 14.37 years) and Pennsylvania (PA; N = 681,…
Teachers' Collective Efficacy, Job Satisfaction, and Job Stress in Cross-Cultural Context
ERIC Educational Resources Information Center
Klassen, Robert M.; Usher, Ellen L.; Bong, Mimi
2010-01-01
This study examines how teachers' collective efficacy (TCE), job stress, and the cultural dimension of collectivism are associated with job satisfaction for 500 teachers from Canada, Korea (South Korea or Republic of Korea), and the United States. Multigroup path analysis revealed that TCE predicted job satisfaction across settings. Job stress was…
ERIC Educational Resources Information Center
Kulas, John T.; Thompson, Richard C.; Anderson, Michael G.
2011-01-01
The California Psychological Inventory's Dominance scale was investigated for inconsistencies in item-trait associations across four samples (one American normative and three culturally dissociated manager groupings). The Kim, Cohen, and Park procedure was used, enabling simultaneous multigroup comparison in addition to the traditional…
Effects of an Early Numeracy Intervention on Struggling Kindergarteners' Mathematics Performance
ERIC Educational Resources Information Center
Bryant, Brian R.; Bryant, Diane Pedrotty; Roberts, Greg; Fall, Anna-Maria
2016-01-01
The purpose of this study was to investigate the effects of an early numeracy intervention delivered by kindergarten teachers to students identified as having mathematics difficulties. A multigroup growth-modeling-with-random-assignment-to-intervention-condition design was employed. Thirty-two teachers were randomly assigned to the treatment or…
Measurement Invariance of the "Servant Leadership Questionnaire" across K-12 Principal Gender
ERIC Educational Resources Information Center
Xu, Lihua; Stewart, Trae; Haber-Curran, Paige
2015-01-01
Measurement invariance of the five-factor "Servant Leadership Questionnaire" between female and male K-12 principals was tested using multi-group confirmatory factor analysis. A sample of 956 principals (56.9% were females and 43.1% were males) was analysed in this study. The hierarchical multi-step measurement invariance test supported…
Multi-Group Invariance of the Conceptions of Assessment Scale among University Faculty and Students
ERIC Educational Resources Information Center
DiLoreto, Melanie Anne
2013-01-01
Conceptions are contextual. In the realm of education, conceptions of various constituent groups are often shaped over a period of a number of years during which time these groups have participated in educational endeavors. Specifically, conceptions of assessment are influenced by beliefs, actions, attitudes, understandings, and past experiences.…
Happy Spouses, Happy Parents? Family Relationships among Finnish and Dutch Dual Earners
ERIC Educational Resources Information Center
Malinen, Kaisa; Kinnunen, Ulla; Tolvanen, Asko; Ronka, Anna; Wierda-Boer, Hilde; Gerris, Jan
2010-01-01
In this study links between spousal and parent-child relationships among Finnish (n = 157 couples) and Dutch (n = 276 couples) dual earners with young children were examined using paired questionnaire data. Variable-oriented analyses (structural equation modeling with a multigroup procedure) supported the spillover hypothesis, as higher levels of…
Queensland Teachers' Conceptions of Assessment: The Impact of Policy Priorities on Teacher Attitudes
ERIC Educational Resources Information Center
Brown, Gavin T. L.; Lake, Robert; Matters, Gabrielle
2011-01-01
The conceptions Queensland teachers have about assessment purposes were surveyed in 2003 with an abridged version of the Teacher Conceptions of Assessment Inventory. Multi-group analysis found that a model with four factors, somewhat different in structure to previous studies, was statistically different between Queensland primary and (lower)…
ERIC Educational Resources Information Center
Martin, Andrew J.; Martin, Tamica G.; Evans, Paul
2018-01-01
This study explored motivation and engagement among 585 Jamaican middle and high school students. Motivation and engagement were assessed via students' responses to the Motivation and Engagement Scale. Confirmatory factor analysis (CFA) found satisfactory fit, and by most measures, multigroup CFA demonstrated comparable factor structure for males…
Validation of the WIMSD4M cross-section generation code with benchmark results
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deen, J.R.; Woodruff, W.L.; Leal, L.E.
1995-01-01
The WIMSD4 code has been adopted for cross-section generation in support of the Reduced Enrichment Research and Test Reactor (RERTR) program at Argonne National Laboratory (ANL). Subsequently, the code has undergone several updates, and significant improvements have been achieved. The capability of generating group-collapsed micro- or macroscopic cross sections from the ENDF/B-V library and the more recent evaluation, ENDF/B-VI, in the ISOTXS format makes the modified version of the WIMSD4 code, WIMSD4M, very attractive, not only for the RERTR program, but also for the reactor physics community. The intent of the present paper is to validate the WIMSD4M cross-section librariesmore » for reactor modeling of fresh water moderated cores. The results of calculations performed with multigroup cross-section data generated with the WIMSD4M code will be compared against experimental results. These results correspond to calculations carried out with thermal reactor benchmarks of the Oak Ridge National Laboratory (ORNL) unreflected HEU critical spheres, the TRX LEU critical experiments, and calculations of a modified Los Alamos HEU D{sub 2}O moderated benchmark critical system. The benchmark calculations were performed with the discrete-ordinates transport code, TWODANT, using WIMSD4M cross-section data. Transport calculations using the XSDRNPM module of the SCALE code system are also included. In addition to transport calculations, diffusion calculations with the DIF3D code were also carried out, since the DIF3D code is used in the RERTR program for reactor analysis and design. For completeness, Monte Carlo results of calculations performed with the VIM and MCNP codes are also presented.« less
Vieno, Alessio; Santinello, Massimo; Pastore, Massimiliano; Perkins, Douglas D
2007-03-01
Influences of different sources of social support (from parents and friends), school sense of community, and self-efficacy on psychosocial well being (as measured by self-reported life satisfaction and psychological symptoms) in early adolescence were investigated in an integrative model. The model was tested using structural equation modeling. Multi-group comparisons were used to estimate differences between sex and age groups. The survey sample was composed of 7,097 students in Northern Italy (51.4% male) divided into three age cohorts (equivalent to 6th, 8th, and 10th grades with median ages of 11, 13, and 15). Findings obtained using SEM were consistent with self-efficacy and school sense of community mediating effects of social support on psychosocial adjustment. The multi-group comparison indicates a need for more complex developmental models and more research on how changing forms of support interact with each other as their effects also change during this important stage of the life. Implications for primary prevention and cross-cultural comparisons are discussed.
Olson, Gordon L.
2015-09-24
One-dimensional models for the transport of radiation through binary stochastic media do not work in multi-dimensions. In addition, authors have attempted to modify or extend the 1D models to work in multidimensions without success. Analytic one-dimensional models are successful in 1D only when assuming greatly simplified physics. State of the art theories for stochastic media radiation transport do not address multi-dimensions and temperature-dependent physics coefficients. Here, the concept of effective opacities and effective heat capacities is found to well represent the ensemble averaged transport solutions in cases with gray or multigroup temperature-dependent opacities and constant or temperature-dependent heat capacities. Inmore » every case analyzed here, effective physics coefficients fit the transport solutions over a useful range of parameter space. The transport equation is solved with the spherical harmonics method with angle orders of n=1 and 5. Although the details depend on what order of solution is used, the general results are similar, independent of angular order.« less
The complexity of personality: advantages of a genetically sensitive multi-group design.
Hahn, Elisabeth; Spinath, Frank M; Siedler, Thomas; Wagner, Gert G; Schupp, Jürgen; Kandler, Christian
2012-03-01
Findings from many behavioral genetic studies utilizing the classical twin design suggest that genetic and non-shared environmental effects play a significant role in human personality traits. This study focuses on the methodological advantages of extending the sampling frame to include multiple dyads of relatives. We investigated the sensitivity of heritability estimates to the inclusion of sibling pairs, mother-child pairs and grandparent-grandchild pairs from the German Socio-Economic Panel Study in addition to a classical German twin sample consisting of monozygotic- and dizygotic twins. The resulting dataset contained 1.308 pairs, including 202 monozygotic and 147 dizygotic twin pairs, along with 419 sibling pairs, 438 mother-child dyads, and 102 grandparent-child dyads. This genetically sensitive multi-group design allowed the simultaneous testing of additive and non-additive genetic, common and specific environmental effects, including cultural transmission and twin-specific environmental influences. Using manifest and latent modeling of phenotypes (i.e., controlling for measurement error), we compare results from the extended sample with those from the twin sample alone and discuss implications for future research.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ghrayeb, Shadi Z.; Ougouag, Abderrafi M.; Ouisloumen, Mohamed
2014-01-01
A multi-group formulation for the exact neutron elastic scattering kernel is developed. It incorporates the neutron up-scattering effects, stemming from lattice atoms thermal motion and accounts for it within the resulting effective nuclear cross-section data. The effects pertain essentially to resonant scattering off of heavy nuclei. The formulation, implemented into a standalone code, produces effective nuclear scattering data that are then supplied directly into the DRAGON lattice physics code where the effects on Doppler Reactivity and neutron flux are demonstrated. The correct accounting for the crystal lattice effects influences the estimated values for the probability of neutron absorption and scattering,more » which in turn affect the estimation of core reactivity and burnup characteristics. The results show an increase in values of Doppler temperature feedback coefficients up to -10% for UOX and MOX LWR fuels compared to the corresponding values derived using the traditional asymptotic elastic scattering kernel. This paper also summarizes the results done on this topic to date.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Olson, Gordon L.
One-dimensional models for the transport of radiation through binary stochastic media do not work in multi-dimensions. In addition, authors have attempted to modify or extend the 1D models to work in multidimensions without success. Analytic one-dimensional models are successful in 1D only when assuming greatly simplified physics. State of the art theories for stochastic media radiation transport do not address multi-dimensions and temperature-dependent physics coefficients. Here, the concept of effective opacities and effective heat capacities is found to well represent the ensemble averaged transport solutions in cases with gray or multigroup temperature-dependent opacities and constant or temperature-dependent heat capacities. Inmore » every case analyzed here, effective physics coefficients fit the transport solutions over a useful range of parameter space. The transport equation is solved with the spherical harmonics method with angle orders of n=1 and 5. Although the details depend on what order of solution is used, the general results are similar, independent of angular order.« less
Hybrid Monte Carlo/deterministic methods for radiation shielding problems
NASA Astrophysics Data System (ADS)
Becker, Troy L.
For the past few decades, the most common type of deep-penetration (shielding) problem simulated using Monte Carlo methods has been the source-detector problem, in which a response is calculated at a single location in space. Traditionally, the nonanalog Monte Carlo methods used to solve these problems have required significant user input to generate and sufficiently optimize the biasing parameters necessary to obtain a statistically reliable solution. It has been demonstrated that this laborious task can be replaced by automated processes that rely on a deterministic adjoint solution to set the biasing parameters---the so-called hybrid methods. The increase in computational power over recent years has also led to interest in obtaining the solution in a region of space much larger than a point detector. In this thesis, we propose two methods for solving problems ranging from source-detector problems to more global calculations---weight windows and the Transform approach. These techniques employ sonic of the same biasing elements that have been used previously; however, the fundamental difference is that here the biasing techniques are used as elements of a comprehensive tool set to distribute Monte Carlo particles in a user-specified way. The weight window achieves the user-specified Monte Carlo particle distribution by imposing a particular weight window on the system, without altering the particle physics. The Transform approach introduces a transform into the neutron transport equation, which results in a complete modification of the particle physics to produce the user-specified Monte Carlo distribution. These methods are tested in a three-dimensional multigroup Monte Carlo code. For a basic shielding problem and a more realistic one, these methods adequately solved source-detector problems and more global calculations. Furthermore, they confirmed that theoretical Monte Carlo particle distributions correspond to the simulated ones, implying that these methods can be used to achieve user-specified Monte Carlo distributions. Overall, the Transform approach performed more efficiently than the weight window methods, but it performed much more efficiently for source-detector problems than for global problems.
Baker, Jason K.; Smith, Leann E.; Greenberg, Jan S.; Seltzer, Marsha Mailick; Taylor, Julie Lounds
2010-01-01
In a previous study from our laboratory, high levels of maternal criticism predicted increased behavior problems in adolescents and adults with autism spectrum disorders (ASD) over an 18-month period (Greenberg, Seltzer, Hong, & Orsmond, 2006). The current investigation followed these families over a period of seven years to examine the longitudinal course of criticism and behavior problems, to assess the association between their trajectories, and to determine the degree to which change in each of these factors predicted levels of criticism and behavior problems at the end of the study period. A sample of 118 mothers co-residing with their adolescents and adults with ASD provided open-ended narratives about their children and reported on the children's behavior problems at four waves. Maternal criticism was derived from expressed emotion ratings of the narratives. Criticism exhibited low but significant stability over the seven year period and behavior problems exhibited high stability. Using latent growth curve modeling, (a) criticism was found to have increased over time, but only for the group of families in which the sons or daughters transitioned from high school services during the study period, (b) individual changes in criticism and behavior problems were positively correlated over the seven-year period, and (c) changes in criticism predicted levels of behavior problems at the conclusion of the study. Changes in behavior problems were not predictive of end levels of criticism. Implications for intervention and prevention efforts are discussed. PMID:21319925
ERIC Educational Resources Information Center
Li, Bi; Wu, Yan; Wen, Zhonglin; Wang, Mengcheng
2014-01-01
This article assessed the measurement in variance of the Adolescent Student Burnout Inventory (ASBI) across gender and educational track, and investigated the main and interaction effects of gender and educational track on the facets of student burnout with a sample consisting of 2,216 adolescent students from China. Multigroup confirmatory factor…
First among Others? Cohen's "d" vs. Alternative Standardized Mean Group Difference Measures
ERIC Educational Resources Information Center
Cahan, Sorel; Gamliel, Eyal
2011-01-01
Standardized effect size measures typically employed in behavioral and social sciences research in the multi-group case (e.g., [eta][superscript 2], f[superscript 2]) evaluate between-group variability in terms of either total or within-group variability, such as variance or standard deviation--that is, measures of dispersion about the mean. In…
ERIC Educational Resources Information Center
Wei, Hsi-Sheng; Chen, Ji-Kang
2012-01-01
This study examined the moderating effect of Machiavellianism on the relationships between bullying, peer acceptance, and school adjustment (rule-following behavior and academic performance) among 216 middle school 7th-graders in Taipei, Taiwan. The participants were divided into two groups according to their Machiavellianism. Multi-group path…
The Korean Diasporic Experience: Measuring Ethnic Identity in the United States and China.
ERIC Educational Resources Information Center
Lee, Richard M.; Falbo, Toni; Doh, Hyun Sim; Park, Seong Yeon
2001-01-01
Korean undergraduates living in the United States and in China were administered the Multigroup Ethnic Identity Measure to assess their ethnic identity. Korean Americans had higher scores on ethnic identity and were more likely to be classified as bicultural, indicating that they were able to retain their cultural heritage while incorporating…
ERIC Educational Resources Information Center
Shapka, Jennifer D.; Onditi, Hezron Z.; Collie, Rebecca J.; Lapidot-Lefler, Noam
2018-01-01
This study explored cyberbullying and cybervictimization (CBCV), for adolescents aged 11-15 from Tanzania (N = 426) and Canada (N = 592). Measurement invariance and model invariance was found for CBCV. In addition, multigroup structural equation modeling was used to explore several variables: age, gender, average hours online each day, accessing…
ERIC Educational Resources Information Center
Sankey, Kim S.; Machin, M. Anthony
2014-01-01
With a focus on the self-initiated efforts of employees, this study examined a model of core proactive motivation processes for participation in non-mandatory professional development (PD) within a proactive motivation framework using the Self-Determination Theory perspective. A multi-group SEM analysis conducted across 439 academic and general…
ERIC Educational Resources Information Center
Nonte, Sonja; Hartwich, Lea; Willems, Ariane S.
2018-01-01
Background: Numerous studies have investigated the relationships between various student, home and contextual factors and reading achievement. However, the relationship between such factors and reading attitudes has been investigated far less, despite the fact that theoretical frameworks of large-scale assessments and school effectiveness research…
ERIC Educational Resources Information Center
Sabik, Natalie J.; Cole, Elizabeth R.; Ward, L. Monique
2010-01-01
Body dissatisfaction is normative among European American women, and involvement with predominant culture or linking self-worth to weight may intensify the association between body dissatisfaction and drive for thinness for women of color. Our study investigated whether orientation to other ethnic groups (Multigroup Ethnic Identity Measure) and…
Exploring the Full-Information Bifactor Model in Vertical Scaling with Construct Shift
ERIC Educational Resources Information Center
Li, Ying; Lissitz, Robert W.
2012-01-01
To address the lack of attention to construct shift in item response theory (IRT) vertical scaling, a multigroup, bifactor model was proposed to model the common dimension for all grades and the grade-specific dimensions. Bifactor model estimation accuracy was evaluated through a simulation study with manipulated factors of percentage of common…
ERIC Educational Resources Information Center
Shek, Daniel T. L.; Ma, Cecilia M. S.
2010-01-01
Objective: This paper examines the dimensionality and factorial invariance of the Chinese Family Assessment Instrument (C-FAI) using multigroup confirmatory factor analyses (MCFAs). Method: A total of 3,649 students responded to the C-FAI in a community survey. Results: Results showed that there are five dimensions of the C-FAI (communication,…
ERIC Educational Resources Information Center
Ursavas, Omer Faruk; Reisoglu, Ilknur
2017-01-01
Purpose: The purpose of this paper is to explore the validity of extended technology acceptance model (TAM) in explaining pre-service teachers' Edmodo acceptance and the variation of variables related to TAM among pre-service teachers having different cognitive styles. Design/methodology/approach: Structural equation modeling approach was used to…
ERIC Educational Resources Information Center
Mousavi, Amin; Krishnan, Vijaya
2016-01-01
The Early Development Instrument (EDI) is a widely used teacher rating tool to assess kindergartners' developmental outcomes in Canada and a number of other countries. This paper examines the measurement invariance of EDI domains across ESL status and gender by means of multi-group confirmatory factor analysis. The results suggest evidence of…
An Exploration of the Effects of Skin Tone on African American Life Experiences.
ERIC Educational Resources Information Center
Breland, Alfiee M.; Collins, Wanda; Damico, Karen Lowenstein; Steward, Robbie; King, Jennifer
This study surveys African Americans to assess perceptions of and life experiences with the issue of skin tone. Thirty-seven African American adults agreed to complete a survey packet and participate in a semi-structured focus group discussion. Participants completed the Rosenberg Self-Esteem Scale, the Multigroup Ethnic Identity Measure, the Skin…
ERIC Educational Resources Information Center
Tze, Virginia M. C.; Klassen, Robert M.; Daniels, Lia M.; Li, Johnson C.-H.; Zhang, Xiao
2013-01-01
This study evaluated the psychometric properties of the Learning-Related Boredom Scale (LRBS) from the Academic Emotions Questionnaire (AEQ; Pekrun, Goetz, & Perry, 2005; Pekrun, Goetz, Titz, & Perry, 2002) in a sample of 405 university students from Canada and China. Multigroup confirmatory factor analysis was used to test the factor…
ERIC Educational Resources Information Center
Randall, Jennifer; Engelhard, George, Jr.
2010-01-01
The psychometric properties and multigroup measurement invariance of scores across subgroups, items, and persons on the "Reading for Meaning" items from the Georgia Criterion Referenced Competency Test (CRCT) were assessed in a sample of 778 seventh-grade students. Specifically, we sought to determine the extent to which score-based…
USDA-ARS?s Scientific Manuscript database
Since the establishment of the brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae) in North America and Europe, there has been a large, multi-group effort to characterize the composition and impact of the indigenous community of arthropod natural enemies attacking this invas...
ERIC Educational Resources Information Center
Kahraman, Nilufer; Brown, Crystal B.
2015-01-01
Psychometric models based on structural equation modeling framework are commonly used in many multiple-choice test settings to assess measurement invariance of test items across examinee subpopulations. The premise of the current article is that they may also be useful in the context of performance assessment tests to test measurement invariance…
ERIC Educational Resources Information Center
Korur, Fikret; Vargas, Rocío Vargas; Torres Serrano, Noemí
2016-01-01
Elementary school teachers' having a positive attitude toward science teaching might encourage students to develop positive attitudes toward science learning. This cross-cultural study aimed to validate the seven-factor structure of the Dimensions of Attitude toward Science (DAS) scale by applying it in two countries. Moreover, it aimed to…
ERIC Educational Resources Information Center
Niileksela, Christopher R.
2012-01-01
Recent advances in the understanding of the relations between cognitive abilities and academic skills have helped shape a better understanding of which cognitive processes may underlie different types of SLD (Flanagan, Fiorello, & Ortiz, 2010). Similarities and differences in cognitive-achievement relations for children with and without SLDs…
A Comparative Study of the Effects of Cultural Differences on the Adoption of Mobile Learning
ERIC Educational Resources Information Center
Arpaci, Ibrahim
2015-01-01
The objective of this paper is to understand the impact of cultural differences on mobile learning adoption through identifying key adoption characteristics in Canada and Turkey, which have markedly different cultural backgrounds. A multi-group analysis was employed to test the hypothesised relationships based on the data collected by means of…
ERIC Educational Resources Information Center
Özyurt, Özcan
2015-01-01
Problem solving is an indispensable part of engineering. Improving critical thinking dispositions for solving engineering problems is one of the objectives of engineering education. In this sense, knowing critical thinking and problem solving skills of engineering students is of importance for engineering education. This study aims to determine…
Yuan, Haobin; Kunaviktikul, Wipada; Klunklin, Areewan; Williams, Beverly A
2008-03-01
A quasi-experimental, two-group pretest-post-test design was conducted to examine the effect of problem-based learning on the critical thinking skills of 46 Year 2 undergraduate nursing students in the People's Republic of China. The California Critical Thinking Skills Test Form A, Chinese-Taiwanese version was used as both a pretest and as a post-test for a semester-long nursing course. There was no significant difference in critical thinking skills at pretest, whereas, significant differences in critical thinking skills existed between the problem-based learning and lecture groups at post-test. The problem-based learning students had a significantly greater improvement on the overall California Critical Thinking Skills Test, analysis, and induction subscale scores compared with the lecture students. Problem-based learning fostered nursing students' critical thinking skills.
Brodrick, Jonathan P.; Kingham, R. J.; Marinak, M. M.; ...
2017-09-06
Three models for nonlocal electron thermal transport are here compared against Vlasov-Fokker-Planck (VFP) codes to assess their accuracy in situations relevant to both inertial fusion hohlraums and tokamak scrape-off layers. The models tested are (i) a moment-based approach using an eigenvector integral closure (EIC) originally developed by Ji, Held, and Sovinec [Phys. Plasmas 16, 022312 (2009)]; (ii) the non-Fourier Landau-fluid (NFLF) model of Dimits, Joseph, and Umansky [Phys. Plasmas 21, 055907 (2014)]; and (iii) Schurtz, Nicolaï, and Busquet’s [Phys. Plasmas 7, 4238 (2000)] multigroup diffusion model (SNB). We find that while the EIC and NFLF models accurately predict the dampingmore » rate of a small-amplitude temperature perturbation (within 10% at moderate collisionalities), they overestimate the peak heat flow by as much as 35% and do not predict preheat in the more relevant case where there is a large temperature difference. The SNB model, however, agrees better with VFP results for the latter problem if care is taken with the definition of the mean free path. Additionally, we present for the first time a comparison of the SNB model against a VFP code for a hohlraum-relevant problem with inhomogeneous ionisation and show that the model overestimates the heat flow in the helium gas-fill by a factor of ~2 despite predicting the peak heat flux to within 16%.« less
NASA Astrophysics Data System (ADS)
Brodrick, J. P.; Kingham, R. J.; Marinak, M. M.; Patel, M. V.; Chankin, A. V.; Omotani, J. T.; Umansky, M. V.; Del Sorbo, D.; Dudson, B.; Parker, J. T.; Kerbel, G. D.; Sherlock, M.; Ridgers, C. P.
2017-09-01
Three models for nonlocal electron thermal transport are here compared against Vlasov-Fokker-Planck (VFP) codes to assess their accuracy in situations relevant to both inertial fusion hohlraums and tokamak scrape-off layers. The models tested are (i) a moment-based approach using an eigenvector integral closure (EIC) originally developed by Ji, Held, and Sovinec [Phys. Plasmas 16, 022312 (2009)]; (ii) the non-Fourier Landau-fluid (NFLF) model of Dimits, Joseph, and Umansky [Phys. Plasmas 21, 055907 (2014)]; and (iii) Schurtz, Nicolaï, and Busquet's [Phys. Plasmas 7, 4238 (2000)] multigroup diffusion model (SNB). We find that while the EIC and NFLF models accurately predict the damping rate of a small-amplitude temperature perturbation (within 10% at moderate collisionalities), they overestimate the peak heat flow by as much as 35% and do not predict preheat in the more relevant case where there is a large temperature difference. The SNB model, however, agrees better with VFP results for the latter problem if care is taken with the definition of the mean free path. Additionally, we present for the first time a comparison of the SNB model against a VFP code for a hohlraum-relevant problem with inhomogeneous ionisation and show that the model overestimates the heat flow in the helium gas-fill by a factor of ˜2 despite predicting the peak heat flux to within 16%.
New evidence of factor structure and measurement invariance of the SDQ across five European nations.
Ortuño-Sierra, Javier; Fonseca-Pedrero, Eduardo; Aritio-Solana, Rebeca; Velasco, Alvaro Moreno; de Luis, Edurne Chocarro; Schumann, Gunter; Cattrell, Anna; Flor, Herta; Nees, Frauke; Banaschewski, Tobias; Bokde, Arun; Whelan, Rob; Buechel, Christian; Bromberg, Uli; Conrod, Patricia; Frouin, Vincent; Papadopoulos, Dimitri; Gallinat, Juergen; Garavan, Hugh; Heinz, Andreas; Walter, Henrik; Struve, Maren; Gowland, Penny; Paus, Tomáš; Poustka, Luise; Martinot, Jean-Luc; Paillère-Martinot, Marie-Laure; Vetter, Nora C; Smolka, Michael N; Lawrence, Claire
2015-12-01
The main purpose of the present study was to analyse the internal structure and to test the measurement invariance of the Strengths and Difficulties Questionnaire (SDQ), self-reported version, in five European countries. The sample consisted of 3012 adolescents aged between 12 and 17 years (M = 14.20; SD = 0.83). The five-factor model (with correlated errors added), and the five-factor model (with correlated errors added) with the reverse-worded items allowed to cross-load on the Prosocial subscale, displayed adequate goodness of-fit indices. Multi-group confirmatory factor analysis showed that the five-factor model (with correlated errors added) had partial strong measurement invariance by countries. A total of 11 of the 25 items were non-invariant across samples. The level of internal consistency of the Total difficulties score was 0.84, ranging between 0.69 and 0.78 for the SDQ subscales. The findings indicate that the SDQ's subscales need to be modified in various ways for screening emotional and behavioural problems in the five European countries that were analysed.
Janssens, Annelies; Van Den Noortgate, Wim; Goossens, Luc; Verschueren, Karine; Colpin, Hilde; Claes, Stephan; Van Heel, Martijn; Van Leeuwen, Karla
2017-09-01
This study investigated (1) reciprocal links among parental psychological control, peer rejection, and adolescent externalizing (aggressive and rule-breaking behaviour), and (2) the moderating effect of an adolescent genetic factor (biologically informed polygenic score for dopamine signalling). Three-year longitudinal data from 1,116 adolescents (51% boys; M age = 13.79) and their parents included psychological measures (adolescent-reported psychological control, peer-reported rejection, and parent-reported aggressive and rule-breaking behaviour). Cross-lagged analyses showed bidirectional effects between psychological control and both aggressive and rule-breaking behaviour and a unidirectional effect of peer rejection on both forms of problem behaviour over time. Multigroup structural equation modelling revealed genetic moderation only for rule-breaking behaviour: for adolescents with intermediate levels of dopamine signalling significant environmental effects were present, whereas adolescent effects of rule-breaking behaviour on psychological control were significant for adolescents with both intermediate and high profiles and effects on peer rejection only for adolescents with high dopamine profiles. Statement of contribution What is already known on this subject? Parental psychological control is related to adolescent externalizing problems. Experiencing peer rejection reinforces aggressive and rule-breaking behaviour. Single-gene studies show that dopaminergic genes influence externalizing problems directly or in interaction with the environment. What does this study add? Parental psychological control and adolescent aggressive and rule-breaking behaviour exacerbate one another longitudinally. Longitudinal associations between peer rejection and both subtypes of externalizing behaviour are unidirectional. With a polygenic approach, dopaminergic moderation is present for rule-breaking behaviour only. © 2017 The British Psychological Society.
Chan, Zenobia C Y
2013-08-01
To explore students' attitude towards problem-based learning, creativity and critical thinking, and the relevance to nursing education and clinical practice. Critical thinking and creativity are crucial in nursing education. The teaching approach of problem-based learning can help to reduce the difficulties of nurturing problem-solving skills. However, there is little in the literature on how to improve the effectiveness of a problem-based learning lesson by designing appropriate and innovative activities such as composing songs, writing poems and using role plays. Exploratory qualitative study. A sample of 100 students participated in seven semi-structured focus groups, of which two were innovative groups and five were standard groups, adopting three activities in problem-based learning, namely composing songs, writing poems and performing role plays. The data were analysed using thematic analysis. There are three themes extracted from the conversations: 'students' perceptions of problem-based learning', 'students' perceptions of creative thinking' and 'students' perceptions of critical thinking'. Participants generally agreed that critical thinking is more important than creativity in problem-based learning and clinical practice. Participants in the innovative groups perceived a significantly closer relationship between critical thinking and nursing care, and between creativity and nursing care than the standard groups. Both standard and innovative groups agreed that problem-based learning could significantly increase their critical thinking and problem-solving skills. Further, by composing songs, writing poems and using role plays, the innovative groups had significantly increased their awareness of the relationship among critical thinking, creativity and nursing care. Nursing educators should include more types of creative activities than it often does in conventional problem-based learning classes. The results could help nurse educators design an appropriate curriculum for preparing professional and ethical nurses for future clinical practice. © 2013 Blackwell Publishing Ltd.
Calculated criticality for sup 235 U/graphite systems using the VIM Monte Carlo code
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collins, P.J.; Grasseschi, G.L.; Olsen, D.N.
1992-01-01
Calculations for highly enriched uranium and graphite systems gained renewed interest recently for the new production modular high-temperature gas-cooled reactor (MHTGR). Experiments to validate the physics calculations for these systems are being prepared for the Transient Reactor Test Facility (TREAT) reactor at Argonne National Laboratory (ANL-West) and in the Compact Nuclear Power Source facility at Los Alamos National Laboratory. The continuous-energy Monte Carlo code VIM, or equivalently the MCNP code, can utilize fully detailed models of the MHTGR and serve as benchmarks for the approximate multigroup methods necessary in full reactor calculations. Validation of these codes and their associated nuclearmore » data did not exist for highly enriched {sup 235}U/graphite systems. Experimental data, used in development of more approximate methods, dates back to the 1960s. The authors have selected two independent sets of experiments for calculation with the VIM code. The carbon-to-uranium (C/U) ratios encompass the range of 2,000, representative of the new production MHTGR, to the ratio of 10,000 in the fuel of TREAT. Calculations used the ENDF/B-V data.« less
Tissue-aware RNA-Seq processing and normalization for heterogeneous and sparse data.
Paulson, Joseph N; Chen, Cho-Yi; Lopes-Ramos, Camila M; Kuijjer, Marieke L; Platig, John; Sonawane, Abhijeet R; Fagny, Maud; Glass, Kimberly; Quackenbush, John
2017-10-03
Although ultrahigh-throughput RNA-Sequencing has become the dominant technology for genome-wide transcriptional profiling, the vast majority of RNA-Seq studies typically profile only tens of samples, and most analytical pipelines are optimized for these smaller studies. However, projects are generating ever-larger data sets comprising RNA-Seq data from hundreds or thousands of samples, often collected at multiple centers and from diverse tissues. These complex data sets present significant analytical challenges due to batch and tissue effects, but provide the opportunity to revisit the assumptions and methods that we use to preprocess, normalize, and filter RNA-Seq data - critical first steps for any subsequent analysis. We find that analysis of large RNA-Seq data sets requires both careful quality control and the need to account for sparsity due to the heterogeneity intrinsic in multi-group studies. We developed Yet Another RNA Normalization software pipeline (YARN), that includes quality control and preprocessing, gene filtering, and normalization steps designed to facilitate downstream analysis of large, heterogeneous RNA-Seq data sets and we demonstrate its use with data from the Genotype-Tissue Expression (GTEx) project. An R package instantiating YARN is available at http://bioconductor.org/packages/yarn .
A physical and economic model of the nuclear fuel cycle
NASA Astrophysics Data System (ADS)
Schneider, Erich Alfred
A model of the nuclear fuel cycle that is suitable for use in strategic planning and economic forecasting is presented. The model, to be made available as a stand-alone software package, requires only a small set of fuel cycle and reactor specific input parameters. Critical design criteria include ease of use by nonspecialists, suppression of errors to within a range dictated by unit cost uncertainties, and limitation of runtime to under one minute on a typical desktop computer. Collision probability approximations to the neutron transport equation that lead to a computationally efficient decoupling of the spatial and energy variables are presented and implemented. The energy dependent flux, governed by coupled integral equations, is treated by multigroup or continuous thermalization methods. The model's output includes a comprehensive nuclear materials flowchart that begins with ore requirements, calculates the buildup of 24 actinides as well as fission products, and concludes with spent fuel or reprocessed material composition. The costs, direct and hidden, of the fuel cycle under study are also computed. In addition to direct disposal and plutonium recycling strategies in current use, the model addresses hypothetical cycles. These include cycles chosen for minor actinide burning and for their low weapons-usable content.
ERIC Educational Resources Information Center
You, Sukkyung; Furlong, Michael; Felix, Erika; O'Malley, Meagan
2015-01-01
Social-emotional health influences youth developmental trajectories and there is growing interest among educators to measure the social-emotional health of the students they serve. This study replicated the psychometric characteristics of the Social Emotional Health Survey (SEHS) with a diverse sample of high school students (Grades 9-12; N =…
ERIC Educational Resources Information Center
Martin, A. J.; Yu, Kai; Hau, Kit-Tai
2014-01-01
The present study investigated multidimensional motivation and engagement among Chinese middle school students in Australia (N?=?273), Hong Kong (N?=?528), and Mainland China (N?=?2106; randomly selected N?=?528). Findings showed that a multidimensional model of motivation and engagement fit very well for all three groups. Multi-group invariance…
ERIC Educational Resources Information Center
Tay, Louis; Huang, Qiming; Vermunt, Jeroen K.
2016-01-01
In large-scale testing, the use of multigroup approaches is limited for assessing differential item functioning (DIF) across multiple variables as DIF is examined for each variable separately. In contrast, the item response theory with covariate (IRT-C) procedure can be used to examine DIF across multiple variables (covariates) simultaneously. To…
ERIC Educational Resources Information Center
Naglieri, Jack A.; Taddei, Stefano; Williams, Kevin M.
2013-01-01
This study examined Italian and U.S. children's performance on the English and Italian versions, respectively, of the Cognitive Assessment System (CAS; Naglieri & Conway, 2009; Naglieri & Das, 1997), a test based on a neurocognitive theory of intelligence entitled PASS (Planning, Attention, Simultaneous, and Successive; Naglieri & Das,…
ERIC Educational Resources Information Center
Teo, Timothy; Noyes, Jan
2014-01-01
Pre-service teachers' self-reported intentions to use information technology were studied. Two hundred and sixty-four participants completed a survey questionnaire measuring their responses to four constructs (performance expectancy, effort expectancy, social influence and facilitating conditions) derived from the Unified Theory of Acceptance and…
ERIC Educational Resources Information Center
Marsh, Herbert W.; Tracey, Danielle K.; Craven, Rhonda G.
2006-01-01
Confirmatory factor analysis of responses by 211 preadolescents (M age = 10.25 years,SD = 1.48) with mild intellectual disabilities (MIDs) to the individually administered Self Description Questionnaire I-Individual Administration (SDQI-IA) counters widely cited claims that these children cannot differentiate multiple self-concept factors. Results…
Shielding analyses: the rabbit vs the turtle?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Broadhead, B.L.
1996-12-31
This paper compares solutions using Monte Carlo and discrete- ordinates methods applied to two actual shielding situations in order to make some general observations concerning the efficiency and advantages/disadvantages of the two approaches. The discrete- ordinates solutions are performed using two-dimensional geometries, while the Monte Carlo approaches utilize three-dimensional geometries with both multigroup and point cross-section data.
ERIC Educational Resources Information Center
Olver, Mark E.; Neumann, Craig S.; Wong, Stephen C. P.; Hare, Robert D.
2013-01-01
We examined the structural and predictive properties of the Psychopathy Checklist-Revised (PCL-R) in large samples of Canadian male Aboriginal and non-Aboriginal offenders. The PCL-R ratings were part of a risk assessment for criminal recidivism, with a mean follow-up of 26 months postrelease. Using multigroup confirmatory factor analysis, we were…
ERIC Educational Resources Information Center
Salanova, Marisa; Llorens, Susana; Garcia-Renedo, Monica; Burriel, Raul; Breso, Edgar; Schaufeli, Wilmar B.
2005-01-01
This article investigated whether cynicism and depersonalization are two different dimensions of burnout or whether they may be collapsed into one construct of mental distance. Using confirmatory factor analyses in two samples of teachers (n = 483) and blue-collar workers (n = 474), a superior fit was found for the four-factor model that contained…
ERIC Educational Resources Information Center
Keith, Timothy Z.; Reynolds, Matthew R.; Roberts, Lisa G.; Winter, Amanda L.; Austin, Cynthia A.
2011-01-01
Sex differences in the latent general and broad cognitive abilities underlying the Differential Ability Scales, Second Edition were investigated for children and youth ages 5 through 17. Multi-group mean and covariance structural equation modeling was used to investigate sex differences in latent cognitive abilities as well as changes in these…
ERIC Educational Resources Information Center
Hentges, Rochelle F.; Wang, Ming-Te
2018-01-01
This study utilized life history theory to test a developmental cascade model linking harsh parenting to low educational attainment. Multigroup models were examined to test for potential gender differences. The sample consisted of 1,482 adolescents followed up for 9 years starting in seventh grade (M[subscript age] = 12.74). Results supported…
ERIC Educational Resources Information Center
Morony, Suzanne; Kleitman, Sabina; Lee, Yim Ping; Stankov, Lazar
2013-01-01
This study investigates the structure and cross-cultural (in)variance of mathematical self-beliefs in relation to mathematics achievement in two world regions: Confucian Asia (Singapore, South Korea, Hong Kong and Taiwan) and Europe (Denmark, The Netherlands, Finland, Serbia and Latvia). This is done both pan-culturally and at a multigroup-level,…
ERIC Educational Resources Information Center
Worrell, Frank C.
2007-01-01
In this study, academically talented African American (n = 28), Asian American (n = 171), Hispanic (n = 28), and White (n = 92) middle and high school students are compared on ethnic identity (EI) and other group orientation (OGO) attitudes as measured by the Multigroup Ethnic Identity Measure. The contributions of these variables to self-esteem…
ERIC Educational Resources Information Center
De Bolle, Marleen; De Fruyt, Filip; Decuyper, Mieke
2010-01-01
Psychometric properties of the Dutch version of the Affect and Arousal Scales (AFARS) were inspected in a combined clinical and population sample (N = 1,215). The validity of the tripartite structure and the relations between Negative Affect, Positive Affect, and Physiological Hyperarousal (PH) were investigated for boys and girls, younger (8-11…
ERIC Educational Resources Information Center
Hoferichter, Frances; Raufelder, Diana; Eid, Michael; Bukowski, William M.
2014-01-01
This cross-national study investigates the perception of the impact of students' relationships towards teachers and peers on scholastic motivation in a total sample of 1477 seventh and eighth grade German (N?=?1088) and Canadian (N?=?389) secondary school students. By applying Multigroup Confirmatory Latent Class Analysis in Mplus we confirmed…
ERIC Educational Resources Information Center
Xiao, Jing; Bai, Yu; He, Yini; McWhinnie, Chad M.; Ling, Yu; Smith, Hannah; Huebner, E. Scott
2016-01-01
The aim of this study was to test the gender invariance of the Chinese version of the Achievement Goal Questionnaire (AGQ-C) utilizing a sample of 1,115 Chinese university students. Multi-group confirmatory factor analysis supported the configural, metric, and scalar invariance of the AGQ-C across genders. Analyses also revealed that the latent…
A Cross-Cultural Test of the Work-Family Interface in 48 Countries
ERIC Educational Resources Information Center
Jeffrey Hill, E.; Yang, Chongming; Hawkins, Alan J.; Ferris, Maria
2004-01-01
This study tests a cross-cultural model of the work-family interface. Using multigroup structural equation modeling with IBM survey responses from 48 countries (N= 25,380), results show that the same work-family interface model that fits the data globally also fits the data in a four-group model composed of culturally related groups of countries,…
Travelling Wave Solutions in Multigroup Age-Structured Epidemic Models
NASA Astrophysics Data System (ADS)
Ducrot, Arnaut; Magal, Pierre; Ruan, Shigui
2010-01-01
Age-structured epidemic models have been used to describe either the age of individuals or the age of infection of certain diseases and to determine how these characteristics affect the outcomes and consequences of epidemiological processes. Most results on age-structured epidemic models focus on the existence, uniqueness, and convergence to disease equilibria of solutions. In this paper we investigate the existence of travelling wave solutions in a deterministic age-structured model describing the circulation of a disease within a population of multigroups. Individuals of each group are able to move with a random walk which is modelled by the classical Fickian diffusion and are classified into two subclasses, susceptible and infective. A susceptible individual in a given group can be crisscross infected by direct contact with infective individuals of possibly any group. This process of transmission can depend upon the age of the disease of infected individuals. The goal of this paper is to provide sufficient conditions that ensure the existence of travelling wave solutions for the age-structured epidemic model. The case of two population groups is numerically investigated which applies to the crisscross transmission of feline immunodeficiency virus (FIV) and some sexual transmission diseases.
Trends in Racial and Ethnic Disparities in Infant Mortality Rates in the United States, 1989–2006
Rossen, Lauren M.; Schoendorf, Kenneth C.
2014-01-01
Objectives. We sought to measure overall disparities in pregnancy outcome, incorporating data from the many race and ethnic groups that compose the US population, to improve understanding of how disparities may have changed over time. Methods. We used Birth Cohort Linked Birth–Infant Death Data Files from US Vital Statistics from 1989–1990 and 2005–2006 to examine multigroup indices of racial and ethnic disparities in the overall infant mortality rate (IMR), preterm birth rate, and gestational age–specific IMRs. We calculated selected absolute and relative multigroup disparity metrics weighting subgroups equally and by population size. Results. Overall IMR decreased on the absolute scale, but increased on the population-weighted relative scale. Disparities in the preterm birth rate decreased on both the absolute and relative scales, and across equally weighted and population-weighted indices. Disparities in preterm IMR increased on both the absolute and relative scales. Conclusions. Infant mortality is a common bellwether of general and maternal and child health. Despite significant decreases in disparities in the preterm birth rate, relative disparities in overall and preterm IMRs increased significantly over the past 20 years. PMID:24028239
Testing of the ABBN-RF multigroup data library in photon transport calculations
NASA Astrophysics Data System (ADS)
Koscheev, Vladimir; Lomakov, Gleb; Manturov, Gennady; Tsiboulia, Anatoly
2017-09-01
Gamma radiation is produced via both of nuclear fuel and shield materials. Photon interaction is known with appropriate accuracy, but secondary gamma ray production known much less. The purpose of this work is studying secondary gamma ray production data from neutron induced reactions in iron and lead by using MCNP code and modern nuclear data as ROSFOND, ENDF/B-7.1, JEFF-3.2 and JENDL-4.0. Results of calculations show that all of these nuclear data have different photon production data from neutron induced reactions and have poor agreement with evaluated benchmark experiment. The ABBN-RF multigroup cross-section library is based on the ROSFOND data. It presented in two forms of micro cross sections: ABBN and MATXS formats. Comparison of group-wise calculations using both ABBN and MATXS data to point-wise calculations with the ROSFOND library shows a good agreement. The discrepancies between calculation and experimental C/E results in neutron spectra are in the limit of experimental errors. For the photon spectrum they are out of experimental errors. Results of calculations using group-wise and point-wise representation of cross sections show a good agreement both for photon and neutron spectra.
Stability analysis of multi-group deterministic and stochastic epidemic models with vaccination rate
NASA Astrophysics Data System (ADS)
Wang, Zhi-Gang; Gao, Rui-Mei; Fan, Xiao-Ming; Han, Qi-Xing
2014-09-01
We discuss in this paper a deterministic multi-group MSIR epidemic model with a vaccination rate, the basic reproduction number ℛ0, a key parameter in epidemiology, is a threshold which determines the persistence or extinction of the disease. By using Lyapunov function techniques, we show if ℛ0 is greater than 1 and the deterministic model obeys some conditions, then the disease will prevail, the infective persists and the endemic state is asymptotically stable in a feasible region. If ℛ0 is less than or equal to 1, then the infective disappear so the disease dies out. In addition, stochastic noises around the endemic equilibrium will be added to the deterministic MSIR model in order that the deterministic model is extended to a system of stochastic ordinary differential equations. In the stochastic version, we carry out a detailed analysis on the asymptotic behavior of the stochastic model. In addition, regarding the value of ℛ0, when the stochastic system obeys some conditions and ℛ0 is greater than 1, we deduce the stochastic system is stochastically asymptotically stable. Finally, the deterministic and stochastic model dynamics are illustrated through computer simulations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jenquin, U.P.; Stewart, K.B.; Heeb, C.M.
1975-07-01
The principal aim of this neutron cross-section research is to provide the utility industry with a 'standard nuclear data base' that will perform satisfactorily when used for analysis of thermal power reactor systems. EPRI is coordinating its activities with those of the Cross Section Evaluation Working Group (CSEWG), responsible for the development of the Evaluated Nuclear Data File-B (ENDF/B) library, in order to improve the performance of the ENDF/B library in thermal reactors and other applications of interest to the utility industry. Battelle-Northwest (BNW) was commissioned to process the ENDF/B Version-4 data files into a group-constant form for use inmore » the LASER and LEOPARD neutronics codes. Performance information on the library should provide the necessary feedback for improving the next version of the library, and a consistent data base is expected to be useful in intercomparing the versions of the LASER and LEOPARD codes presently being used by different utility groups. This report describes the BNW multi-group libraries and the procedures followed in their preparation and testing. (GRA)« less
Napolitano, Christopher M; Job, Veronika
2018-05-21
Why do some people struggle with self-control (colloquially called willpower) whereas others are able to sustain it during challenging circumstances? Recent research showed that a person's implicit theories of willpower-whether they think self-control capacity is a limited or nonlimited resource-predict sustained self-control on laboratory tasks and on goal-related outcomes in everyday life. The present research tests the Implicit Theory of Willpower for Strenuous Mental Activities Scale (or ITW-M) Scale for measurement invariance across samples and gender within each culture, and two cultural contexts (the U.S. and Switzerland/Germany). Across a series of multigroup confirmatory factor analyses, we found support for the measurement invariance of the ITW-M scale across samples within and across two cultures, as well as across men and women. Further, the analyses showed expected patterns of convergent (with life-satisfaction and trait-self-control) and discriminant validity (with implicit theory of intelligence). These results provide guidelines for future research and clinical practice using the ITW-M scale for the investigation of latent group differences, for example, between gender or cultures. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sandmeier, H.A.; Hansen, G.E.; Seamon, R.E.
This report lists 42-group, coupled, neutron -gamma cross sections for H, D, T, /sup 3/He, /sup 4/He, /sup 6/Li, /sup 7/Li, Be, /sup 10/B, /sup 11/B, C, N, O, Na, Mg, Ai, Si, Cl, A, K, Ca, Fe, Cu, W, Pb, /sup 235/U, /sup 238/U, / sup 239/Pu, and /sup 240/Pu. Most of these materials are used in nuclear- weaponseffects calculations, where the elements for air, ground, and sea water are needed. Further, lists are given of cross sections for materials used in nuclear weapons vulnerability calculations, such as the elements of high explosives as well as materials that willmore » undergo fusion and fission. Most of the common reactor materials are also listed. The 42 coupled neutron-gamma groups are split into 30 neutron groups (17 MeV through 1.39 x 10/sup -4/ eV) and 12 gamma groups (10 MeV through 0.01 MeV). Data sources and averaging schemes used for the development of these multigroup parameters are given. (119 tables) (auth)« less
Ramírez-Correa, Patricio E; Arenas-Gaitán, Jorge; Rondán-Cataluña, F Javier
2015-01-01
The scope of this study was to evaluate whether the adoption of e-learning in two universities, and in particular, the relationship between the perception of external control and perceived ease of use, is different because of gender differences. The study was carried out with participating students in two different universities, one in Chile and one in Spain. The Technology Acceptance Model was used as a theoretical framework for the study. A multi-group analysis method in partial least squares was employed to relate differences between groups. The four main conclusions of the study are: (1) a version of the Technology Acceptance Model has been successfully used to explain the process of adoption of e-learning at an undergraduate level of study; (2) the finding of a strong and significant relationship between perception of external control and perception of ease of use of the e-learning platform; (3) a significant relationship between perceived enjoyment and perceived ease of use and between results demonstrability and perceived usefulness is found; (4) the study indicates a few statistically significant differences between males and females when adopting an e-learning platform, according to the tested model.
Lau, Ying; Htun, Tha Pyai; Lim, Peng Im; Ho-Lim, Sarah Su Tin; Chi, Claudia; Tsai, Cammy; Ong, Kai Wen; Klainin-Yobas, Piyanee
2017-02-01
Identifying the factors influencing breastfeeding attitude is significant for the implementation of effective promotion policies and counselling activities. To our best knowledge, no previous studies have modelled the relationships among breastfeeding attitude, health-related quality of life and maternal obesity among multi-ethnic pregnant women; the current study attempts to fill this research gap. This study investigated the relationships among maternal characteristics, health-related quality of life and breastfeeding attitude amidst normal weight and overweight/obese pregnant women using a multi-group structural equation modelling approach. Exploratory cross-sectional design was used. Antenatal clinics of a university-affiliated hospital PARTICIPANTS: Pregnant women were invited to participate; 708 (78.8%) agreed to participate in the study. We examined a hypothetical model on the basis of integrating the concepts of a breastfeeding decision-making model, theory of planned behaviour-based model for breastfeeding and health-related quality of life model among 708 multi-ethnic pregnant women in Singapore. The Iowa Infant Feeding Attitude Scale and Medical Outcomes Study Short Form Health Survey were used to measure breastfeeding attitude and health-related quality of life, respectively. Two structural equation models demonstrated that better health-related quality of life, higher monthly household income, planned pregnancy and previous exclusive breastfeeding experience were significantly associated with positive breastfeeding attitude among normal and overweight/obese pregnant women. Among normal weight pregnant women, those who were older with higher educational level were more likely to have positive breastfeeding attitude. Among overweight/obese pregnant women, Chinese women with confinement nanny plan were less likely to have positive breastfeeding attitude. No significant difference existed between normal weight and overweight/obese pregnant women concerning estimates of health-related quality of life on breastfeeding attitude (Critical Ratio=-0.193). The model satisfactorily fitted the data (Incremental Fit Index=0.924, Tucker-Lewis Index=0.905, Comparative Fit Index=0.921 and Root Means Square Error of Approximation=0.025). Health-related quality of life was found to affect breastfeeding attitude in multi-ethnic pregnant women. This relationship implied the importance of early culturally specific interventions to enhance health-related quality of life for improving positive breastfeeding attitude among pregnant women across different ethnic groups. Copyright © 2016 Elsevier Ltd. All rights reserved.
Student’s critical thinking skills in authentic problem based learning
NASA Astrophysics Data System (ADS)
Yuliati, L.; Fauziah, R.; Hidayat, A.
2018-05-01
This study aims to determine students’ critical thinking skills in authentic problem based learning, especially on geometric optics. The study was conducted at the vocational school. The study used a quantitative descriptive method with the open question to measure critical thinking skills. The indicators of critical thinking skills measured in this study are: formulating problems, providing simple answers, applying formulas and procedures, analyzing information, making conclusions, and synthesizing ideas. The results showed that there was a positive change in students’ critical thinking skills with the average value of N-Gain test is 0.59 and effect size test is 3.73. The critical thinking skills of students need to be trained more intensively using authentic problems in daily life.
ERIC Educational Resources Information Center
Temel, Senar
2014-01-01
The aim of this study was two-fold. The first aim was to determine the levels of critical thinking disposition and perception of problem-solving ability of pre-service teachers. The second aim was to compare the effects of problem-based learning and traditional teaching methods on the critical thinking dispositions and perceptions of…
Critical thinking level in geometry based on self-regulated learning
NASA Astrophysics Data System (ADS)
Bayuningsih, A. S.; Usodo, B.; Subanti, S.
2018-03-01
Critical thinking ability of mathematics students affected by the student’s ability in solving a specific problem. This research aims to determine the level of critical thinking (LCT) students in solving problems of geometry regarding self-regulated learning (SRL) students. This is a qualitative descriptive study with the purpose to analyze the level of Junior High School student’s critical thinking in the Regency of Banyumas. The subject is taken one student from each category SRL (high, medium and low). Data collection is given problem-solving tests to find out the level of critical thinking student, questionnaire, interview and documentation. The result of the research shows that student with SRL high is at the level of critical thinking 2, then a student with SRL medium is at the level of critical thinking 1 and student with SRL low is at the level of critical thinking 0. So students with SRL high, medium or low can solve math problems based on the critical thinking level of each student.
Development of Ultra-Fine Multigroup Cross Section Library of the AMPX/SCALE Code Packages
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeon, Byoung Kyu; Sik Yang, Won; Kim, Kang Seog
The Consortium for Advanced Simulation of Light Water Reactors Virtual Environment for Reactor Applications (VERA) neutronic simulator MPACT is being developed by Oak Ridge National Laboratory and the University of Michigan for various reactor applications. The MPACT and simplified MPACT 51- and 252-group cross section libraries have been developed for the MPACT neutron transport calculations by using the AMPX and Standardized Computer Analyses for Licensing Evaluations (SCALE) code packages developed at Oak Ridge National Laboratory. It has been noted that the conventional AMPX/SCALE procedure has limited applications for fast-spectrum systems such as boiling water reactor (BWR) fuels with very highmore » void fractions and fast reactor fuels because of its poor accuracy in unresolved and fast energy regions. This lack of accuracy can introduce additional error sources to MPACT calculations, which is already limited by the Bondarenko approach for resolved resonance self-shielding calculation. To enhance the prediction accuracy of MPACT for fast-spectrum reactor analyses, the accuracy of the AMPX/SCALE code packages should be improved first. The purpose of this study is to identify the major problems of the AMPX/SCALE procedure in generating fast-spectrum cross sections and to devise ways to improve the accuracy. For this, various benchmark problems including a typical pressurized water reactor fuel, BWR fuels with various void fractions, and several fast reactor fuels were analyzed using the AMPX 252-group libraries. Isotopic reaction rates were determined by SCALE multigroup (MG) calculations and compared with continuous energy (CE) Monte Carlo calculation results. This reaction rate analysis revealed three main contributors to the observed differences in reactivity and reaction rates: (1) the limitation of the Bondarenko approach in coarse energy group structure, (2) the normalization issue of probability tables, and (3) neglect of the self-shielding effect of resonance-like cross sections at high energy range such as (n,p) cross section of Cl35. The first error source can be eliminated by an ultra-fine group (UFG) structure in which the broad scattering resonances of intermediate-weight nuclides can be represented accurately by a piecewise constant function. A UFG AMPX library was generated with modified probability tables and tested against various benchmark problems. The reactivity and reaction rates determined with the new UFG AMPX library agreed very well with respect to Monte Carlo Neutral Particle (MCNP) results. To enhance the lattice calculation accuracy without significantly increasing the computational time, performing the UFG lattice calculation in two steps was proposed. In the first step, a UFG slowing-down calculation is performed for the corresponding homogenized composition, and UFG cross sections are collapsed into an intermediate group structure. In the second step, the lattice calculation is performed for the intermediate group level using the condensed group cross sections. A preliminary test showed that the condensed library reproduces the results obtained with the UFG cross section library. This result suggests that the proposed two-step lattice calculation approach is a promising option to enhance the applicability of the AMPX/SCALE system to fast system analysis.« less
The NJOY Nuclear Data Processing System, Version 2016
DOE Office of Scientific and Technical Information (OSTI.GOV)
Macfarlane, Robert; Muir, Douglas W.; Boicourt, R. M.
The NJOY Nuclear Data Processing System, version 2016, is a comprehensive computer code package for producing pointwise and multigroup cross sections and related quantities from evaluated nuclear data in the ENDF-4 through ENDF-6 legacy card-image formats. NJOY works with evaluated files for incident neutrons, photons, and charged particles, producing libraries for a wide variety of particle transport and reactor analysis codes.
ERIC Educational Resources Information Center
Huang, Francis L.; Konold, Timothy R.
2014-01-01
Psychometric properties of the Phonological Awareness Literacy Screening for Kindergarten (PALS-K) instrument were investigated in a sample of 2844 first-time public school kindergarteners. PALS-K is a widely used English literacy screening assessment. Exploratory factor analysis revealed a theoretically defensible measurement structure that was…
ERIC Educational Resources Information Center
Pae, Hye K.; Greenberg, Daphne
2014-01-01
The purpose of this study was to examine the relationship between receptive and expressive language skills characterized by the performance of nonnative speakers (NNSs) of English in the academic context. Test scores of 585 adult NNSs were selected from Form 2 of the Pearson Test of English Academic's field-test database. A correlated…
ERIC Educational Resources Information Center
Lowe, Patricia A.; Ang, Rebecca P.
2016-01-01
Tests of measurement invariance were conducted across culture and gender on the Revised Children's Manifest Anxiety Scale-Second Edition (RCMAS-2) Short Form in a sample of 1,003 Singapore and U.S. adolescents. The results of multi-group confirmatory factor analyses across culture and gender supported at least partial measurement invariance. ANOVA…
ERIC Educational Resources Information Center
Lippke, Sonia; Nigg, Claudio R.; Maddock, Jay E.
2007-01-01
This is the first study to test whether the stages of change of the transtheoretical model are qualitatively different through exploring discontinuity patterns in theory of planned behavior (TPB) variables using latent multigroup structural equation modeling (MSEM) with AMOS. Discontinuity patterns in terms of latent means and prediction patterns…
ERIC Educational Resources Information Center
Massachusetts School Building Assistance Commission, Boston.
This report suggests that the instructional materials center be flexible for multigroup activities, expansible for future physical growth, and central to the instructional program. Area specifications are given for the following areas: materials research, small groups, cataloging and processing materials, and listening and speaking, and for a dark…
ERIC Educational Resources Information Center
Boyd, Michelle J.; Zaff, Jonathan F.; Phelps, Erin; Weiner, Michelle B.; Lerner, Richard M.
2011-01-01
Using data from the 4-H Study of Positive Youth Development, a longitudinal study involving U.S. adolescents, multi-group structural equation modeling (SEM) was used to evaluate whether news media use is predictive of a set of civic indicators (civic duty, civic efficacy, neighborhood social connection, and civic participation) for youth in Grades…
ERIC Educational Resources Information Center
Gonzalez-Roma, Vicente; Tomas, Ines; Ferreres, Doris; Hernandez, Ana
2005-01-01
The aims of this study were to investigate whether the 6 items of the Physical Appearance Scale (Marsh, Richards, Johnson, Roche, & Tremayne, 1994) show differential item functioning (DIF) across gender groups of adolescents, and to show how this can be done using the multigroup mean and covariance structure (MG-MACS) analysis model. Two samples…
ERIC Educational Resources Information Center
Chan, David W.
2011-01-01
This study investigated the structure of perfectionism based on the almost Perfect Scale-Revised with a sample of 320 gifted students aged 7 to 12 and a sample of 882 nongifted students of similar ages in Hong Kong. Multigroup confirmatory factor analyses across the two student groups supported a common three-dimensional model that included…
Reliability and Validity of Assessing User Satisfaction With Web-Based Health Interventions
Lehr, Dirk; Reis, Dorota; Vis, Christiaan; Riper, Heleen; Berking, Matthias; Ebert, David Daniel
2016-01-01
Background The perspective of users should be taken into account in the evaluation of Web-based health interventions. Assessing the users’ satisfaction with the intervention they receive could enhance the evidence for the intervention effects. Thus, there is a need for valid and reliable measures to assess satisfaction with Web-based health interventions. Objective The objective of this study was to analyze the reliability, factorial structure, and construct validity of the Client Satisfaction Questionnaire adapted to Internet-based interventions (CSQ-I). Methods The psychometric quality of the CSQ-I was analyzed in user samples from 2 separate randomized controlled trials evaluating Web-based health interventions, one from a depression prevention intervention (sample 1, N=174) and the other from a stress management intervention (sample 2, N=111). At first, the underlying measurement model of the CSQ-I was analyzed to determine the internal consistency. The factorial structure of the scale and the measurement invariance across groups were tested by multigroup confirmatory factor analyses. Additionally, the construct validity of the scale was examined by comparing satisfaction scores with the primary clinical outcome. Results Multigroup confirmatory analyses on the scale yielded a one-factorial structure with a good fit (root-mean-square error of approximation =.09, comparative fit index =.96, standardized root-mean-square residual =.05) that showed partial strong invariance across the 2 samples. The scale showed very good reliability, indicated by McDonald omegas of .95 in sample 1 and .93 in sample 2. Significant correlations with change in depressive symptoms (r=−.35, P<.001) and perceived stress (r=−.48, P<.001) demonstrated the construct validity of the scale. Conclusions The proven internal consistency, factorial structure, and construct validity of the CSQ-I indicate a good overall psychometric quality of the measure to assess the user’s general satisfaction with Web-based interventions for depression and stress management. Multigroup analyses indicate its robustness across different samples. Thus, the CSQ-I seems to be a suitable measure to consider the user’s perspective in the overall evaluation of Web-based health interventions. PMID:27582341
Reliability and Validity of Assessing User Satisfaction With Web-Based Health Interventions.
Boß, Leif; Lehr, Dirk; Reis, Dorota; Vis, Christiaan; Riper, Heleen; Berking, Matthias; Ebert, David Daniel
2016-08-31
The perspective of users should be taken into account in the evaluation of Web-based health interventions. Assessing the users' satisfaction with the intervention they receive could enhance the evidence for the intervention effects. Thus, there is a need for valid and reliable measures to assess satisfaction with Web-based health interventions. The objective of this study was to analyze the reliability, factorial structure, and construct validity of the Client Satisfaction Questionnaire adapted to Internet-based interventions (CSQ-I). The psychometric quality of the CSQ-I was analyzed in user samples from 2 separate randomized controlled trials evaluating Web-based health interventions, one from a depression prevention intervention (sample 1, N=174) and the other from a stress management intervention (sample 2, N=111). At first, the underlying measurement model of the CSQ-I was analyzed to determine the internal consistency. The factorial structure of the scale and the measurement invariance across groups were tested by multigroup confirmatory factor analyses. Additionally, the construct validity of the scale was examined by comparing satisfaction scores with the primary clinical outcome. Multigroup confirmatory analyses on the scale yielded a one-factorial structure with a good fit (root-mean-square error of approximation =.09, comparative fit index =.96, standardized root-mean-square residual =.05) that showed partial strong invariance across the 2 samples. The scale showed very good reliability, indicated by McDonald omegas of .95 in sample 1 and .93 in sample 2. Significant correlations with change in depressive symptoms (r=-.35, P<.001) and perceived stress (r=-.48, P<.001) demonstrated the construct validity of the scale. The proven internal consistency, factorial structure, and construct validity of the CSQ-I indicate a good overall psychometric quality of the measure to assess the user's general satisfaction with Web-based interventions for depression and stress management. Multigroup analyses indicate its robustness across different samples. Thus, the CSQ-I seems to be a suitable measure to consider the user's perspective in the overall evaluation of Web-based health interventions.
Messy Problems and Lay Audiences: Teaching Critical Thinking within the Finance Curriculum
ERIC Educational Resources Information Center
Carrithers, David; Ling, Teresa; Bean, John C.
2008-01-01
This article investigates the critical thinking difficulties of finance majors when asked to address ill-structured finance problems. The authors build on previous research in which they asked students to analyze an ill-structured investment problem and recommend a course of action. The results revealed numerous critical thinking weaknesses,…
Cardiac emergencies and problems of the critical care patient.
Marr, Celia M
2004-04-01
Cardiac disease and dysfunction can occur as a primary disorder(ie, with pathology situated in one or more of the cardiac structures) or can be classified as a secondary problem when it occurs in patients with another primary problem that has affected the heart either directly or indirectly. Primary cardiac problems are encountered in horses presented to emergency clinics; however,this occurs much less frequently in equine critical patients than cardiac problems arising secondary to other conditions. Nevertheless,if primary or secondary cardiac problems are not identified and addressed, they certainly contribute to the morbidity and mortality of critical care patients.
Feed Forward Neural Network and Optimal Control Problem with Control and State Constraints
NASA Astrophysics Data System (ADS)
Kmet', Tibor; Kmet'ová, Mária
2009-09-01
A feed forward neural network based optimal control synthesis is presented for solving optimal control problems with control and state constraints. The paper extends adaptive critic neural network architecture proposed by [5] to the optimal control problems with control and state constraints. The optimal control problem is transcribed into a nonlinear programming problem which is implemented with adaptive critic neural network. The proposed simulation method is illustrated by the optimal control problem of nitrogen transformation cycle model. Results show that adaptive critic based systematic approach holds promise for obtaining the optimal control with control and state constraints.
The effect of critical thinking education on nursing students' problem-solving skills.
Kanbay, Yalçın; Okanlı, Ayşe
2017-06-01
The aim of this study is to examine the effect of critical thinking education on nursing students' problem-solving skills. This study was conducted with 93 nursing students, 49 in the control group and 44 in the education group. The California Critical Thinking Disposition Inventory and the Problem-solving Inventory were administered to them before and after 12 weeks of critical thinking education. The education group's mean critical thinking score was 253.61 on the pretest and 268.72 on the posttest. This increase was statistically significant (p < .001). The posttest mean score of the control group fell to 258.18 on the posttest after a pretest mean score of 260.79, and this difference was statistically significant (p < .001). According to the posttest results, the problem-solving skills of education group increased significantly (p < .001), while the control group's score fell significantly (p < .001). This study determined that critical thinking education improves problem-solving skills.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jessee, Matthew Anderson
The SCALE Code System is a widely-used modeling and simulation suite for nuclear safety analysis and design that is developed, maintained, tested, and managed by the Reactor and Nuclear Systems Division (RNSD) of Oak Ridge National Laboratory (ORNL). SCALE provides a comprehensive, verified and validated, user-friendly tool set for criticality safety, reactor and lattice physics, radiation shielding, spent fuel and radioactive source term characterization, and sensitivity and uncertainty analysis. Since 1980, regulators, licensees, and research institutions around the world have used SCALE for safety analysis and design. SCALE provides an integrated framework with dozens of computational modules including three deterministicmore » and three Monte Carlo radiation transport solvers that are selected based on the desired solution strategy. SCALE includes current nuclear data libraries and problem-dependent processing tools for continuous-energy (CE) and multigroup (MG) neutronics and coupled neutron-gamma calculations, as well as activation, depletion, and decay calculations. SCALE includes unique capabilities for automated variance reduction for shielding calculations, as well as sensitivity and uncertainty analysis. SCALE’s graphical user interfaces assist with accurate system modeling, visualization of nuclear data, and convenient access to desired results.SCALE 6.2 provides many new capabilities and significant improvements of existing features.New capabilities include:• ENDF/B-VII.1 nuclear data libraries CE and MG with enhanced group structures,• Neutron covariance data based on ENDF/B-VII.1 and supplemented with ORNL data,• Covariance data for fission product yields and decay constants,• Stochastic uncertainty and correlation quantification for any SCALE sequence with Sampler,• Parallel calculations with KENO,• Problem-dependent temperature corrections for CE calculations,• CE shielding and criticality accident alarm system analysis with MAVRIC,• CE depletion with TRITON (T5-DEPL/T6-DEPL),• CE sensitivity/uncertainty analysis with TSUNAMI-3D,• Simplified and efficient LWR lattice physics with Polaris,• Large scale detailed spent fuel characterization with ORIGAMI and ORIGAMI Automator,• Advanced fission source convergence acceleration capabilities with Sourcerer,• Nuclear data library generation with AMPX, and• Integrated user interface with Fulcrum.Enhanced capabilities include:• Accurate and efficient CE Monte Carlo methods for eigenvalue and fixed source calculations,• Improved MG resonance self-shielding methodologies and data,• Resonance self-shielding with modernized and efficient XSProc integrated into most sequences,• Accelerated calculations with TRITON/NEWT (generally 4x faster than SCALE 6.1),• Spent fuel characterization with 1470 new reactor-specific libraries for ORIGEN,• Modernization of ORIGEN (Chebyshev Rational Approximation Method [CRAM] solver, API for high-performance depletion, new keyword input format)• Extension of the maximum mixture number to values well beyond the previous limit of 2147 to ~2 billion,• Nuclear data formats enabling the use of more than 999 energy groups,• Updated standard composition library to provide more accurate use of natural abundances, andvi• Numerous other enhancements for improved usability and stability.« less
ERIC Educational Resources Information Center
Hedges, Lowell E.
This document contains 48 sample lesson plans that practicing teachers of vocational and academic education have developed to train vocational students to think critically and to solve problems. Discussed in the introduction are the following topics: critical thinking, problem solving, and decision making as the building blocks of teaching;…
ERIC Educational Resources Information Center
Yenice, Nilgun
2011-01-01
This study was conducted to examine pre-service science teachers' critical thinking dispositions and problem solving skills based on gender, grade level and graduated high school variables. Also relationship between pre-service science teachers' critical thinking dispositions and problem solving skills was examined based on gender, grade level and…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Franke, Brian Claude; Kensek, Ronald Patrick; Laub, Thomas William
ITS is a powerful and user-friendly software package permitting state of the art Monte Carlo solution of linear time-independent couple electron/photon radiation transport problems, with or without the presence of macroscopic electric and magnetic fields of arbitrary spatial dependence. Our goal has been to simultaneously maximize operational simplicity and physical accuracy. Through a set of preprocessor directives, the user selects one of the many ITS codes. The ease with which the makefile system is applied combines with an input scheme based on order-independent descriptive keywords that makes maximum use of defaults and internal error checking to provide experimentalists and theoristsmore » alike with a method for the routine but rigorous solution of sophisticated radiation transport problems. Physical rigor is provided by employing accurate cross sections, sampling distributions, and physical models for describing the production and transport of the electron/photon cascade from 1.0 GeV down to 1.0 keV. The availability of source code permits the more sophisticated user to tailor the codes to specific applications and to extend the capabilities of the codes to more complex applications. Version 5.0, the latest version of ITS, contains (1) improvements to the ITS 3.0 continuous-energy codes, (2)multigroup codes with adjoint transport capabilities, and (3) parallel implementations of all ITS codes. Moreover the general user friendliness of the software has been enhanced through increased internal error checking and improved code portability.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
A. T. Till; M. Hanuš; J. Lou
The standard multigroup (MG) method for energy discretization of the transport equation can be sensitive to approximations in the weighting spectrum chosen for cross-section averaging. As a result, MG often inaccurately treats important phenomena such as self-shielding variations across a material. From a finite-element viewpoint, MG uses a single fixed basis function (the pre-selected spectrum) within each group, with no mechanism to adapt to local solution behavior. In this work, we introduce the Finite-Element-with-Discontiguous-Support (FEDS) method, whose only approximation with respect to energy is that the angular flux is a linear combination of unknowns multiplied by basis functions. A basismore » function is non-zero only in the discontiguous set of energy intervals associated with its energy element. Discontiguous energy elements are generalizations of bands and are determined by minimizing a norm of the difference between snapshot spectra and their averages over the energy elements. We begin by presenting the theory of the FEDS method. We then compare to continuous-energy Monte Carlo for one-dimensional slab and two-dimensional pin-cell problem. We find FEDS to be accurate and efficient at producing quantities of interest such as reaction rates and eigenvalues. Results show that FEDS converges at a rate that is approximately first-order in the number of energy elements and that FEDS is less sensitive to weighting spectrum than standard MG.« less
ERIC Educational Resources Information Center
Gorman, Anna M.
To determine priorities for critical problems facing consumer and homemaking education and plan research projects which focus on these critical problems, a 5-day conference was attended by 107 vocational-technical education specialists and educators. Conference sessions were planned to (1) identify critical research problem areas and prepare a…
ERIC Educational Resources Information Center
Dolan, Conor V.; Colom, Roberto; Abad, Francisco J.; Wicherts, Jelte M.; Hessen, David J.; van de Sluis, Sophie
2006-01-01
We investigated sex effects and the effects of educational attainment (EA) on the covariance structure of the WAIS-III in a subsample of the Spanish standardization data. We fitted both first order common factor models and second order common factor models. The latter include general intelligence ("g") as a second order common factor.…
ERIC Educational Resources Information Center
Chang, Edward C.; Yu, Elizabeth A.; Yu, Tina; Kahle, Emma R.; Hernandez, Viviana; Kim, Jean M.; Jeglic, Elizabeth L.; Hirsch, Jameson K.
2016-01-01
In the present study, we examined ethnic variables (viz., multigroup ethnic identity and other group orientation) along with negative life events as predictors of depressive symptoms and suicidal behaviors in a sample of 156 (38 male and 118 female) Latino college students. Results of conducting hierarchical regression analyses indicated that the…
ERIC Educational Resources Information Center
Tarhini, Ali; Scott, Michael James; Sharma, Sujeet Kumar; Abbasi, Muhammad Sharif
2015-01-01
Really Simple Syndication (RSS) offers a means for university students to receive timely updates from virtual learning environments. However, despite its utility, only 21% of home students surveyed at a university in Lebanon claim to have ever used the technology. To investigate whether national culture could be an influence on intention to use…
ERIC Educational Resources Information Center
Meerschman, Iris; Van Lierde, Kristiane; Peeters, Karen; Meersman, Eline; Claeys, Sofie; D'haeseleer, Evelien
2017-01-01
Purpose: The purpose of this study was to determine the short-term effect of 2 semi-occluded vocal tract training programs, "resonant voice training using nasal consonants" versus "straw phonation," on the vocal quality of vocally healthy future occupational voice users. Method: A multigroup pretest--posttest randomized control…
ERIC Educational Resources Information Center
Teo, Timothy; Lee, Chwee Beng; Chai, Ching Sing; Wong, Su Luan
2009-01-01
This study assesses the pre-service teachers' self-reported future intentions to use technology in Singapore and Malaysia. A survey was employed to validate items from past research. Using the Technology Acceptance Model (TAM) as a research framework, 495 pre-service teachers from Singapore and Malaysia responded to an 11-item questionnaires…
ERIC Educational Resources Information Center
Park, Sun Hee; Jun, JuSung
2017-01-01
The purpose of this study was to analyze the structural relationships between parent support, career decision self-efficacy, career maturity, and career preparation behavior for elementary school students (5th and 6th grade) in Korea and to examine if there are gender differences. A total of 609 students of 7 elementary schools in Seoul, Korea was…
ERIC Educational Resources Information Center
Ingles, Candido J.; Marzo, Juan C.; Castejon, Juan L.; Nunez, Jose Carlos; Valle, Antonio; Garcia-Fernandez, Jose M.; Delgado, Beatriz
2011-01-01
This study examined the factorial invariance and latent mean differences of scores on the Spanish version of the "Achievement Goal Tendencies Questionnaire" (AGTQ) across gender and age groups in 2022 Spanish students (51.1% boys) in grades 7 through 10. The equality of factor structures was compared using multi-group confirmatory factor…
2015-01-01
The scope of this study was to evaluate whether the adoption of e-learning in two universities, and in particular, the relationship between the perception of external control and perceived ease of use, is different because of gender differences. The study was carried out with participating students in two different universities, one in Chile and one in Spain. The Technology Acceptance Model was used as a theoretical framework for the study. A multi-group analysis method in partial least squares was employed to relate differences between groups. The four main conclusions of the study are: (1) a version of the Technology Acceptance Model has been successfully used to explain the process of adoption of e-learning at an undergraduate level of study; (2) the finding of a strong and significant relationship between perception of external control and perception of ease of use of the e-learning platform; (3) a significant relationship between perceived enjoyment and perceived ease of use and between results demonstrability and perceived usefulness is found; (4) the study indicates a few statistically significant differences between males and females when adopting an e-learning platform, according to the tested model. PMID:26465895
The Status of Multi-Dimensional Core-Collapse Supernova Models
NASA Astrophysics Data System (ADS)
Müller, B.
2016-09-01
Models of neutrino-driven core-collapse supernova explosions have matured considerably in recent years. Explosions of low-mass progenitors can routinely be simulated in 1D, 2D, and 3D. Nucleosynthesis calculations indicate that these supernovae could be contributors of some lighter neutron-rich elements beyond iron. The explosion mechanism of more massive stars remains under investigation, although first 3D models of neutrino-driven explosions employing multi-group neutrino transport have become available. Together with earlier 2D models and more simplified 3D simulations, these have elucidated the interplay between neutrino heating and hydrodynamic instabilities in the post-shock region that is essential for shock revival. However, some physical ingredients may still need to be added/improved before simulations can robustly explain supernova explosions over a wide range of progenitors. Solutions recently suggested in the literature include uncertainties in the neutrino rates, rotation, and seed perturbations from convective shell burning. We review the implications of 3D simulations of shell burning in supernova progenitors for the `perturbations-aided neutrino-driven mechanism,' whose efficacy is illustrated by the first successful multi-group neutrino hydrodynamics simulation of an 18 solar mass progenitor with 3D initial conditions. We conclude with speculations about the impact of 3D effects on the structure of massive stars through convective boundary mixing.
Self-esteem Is Mostly Stable Across Young Adulthood: Evidence from Latent STARTS Models.
Wagner, Jenny; Lüdtke, Oliver; Trautwein, Ulrich
2016-08-01
How stable is self-esteem? This long-standing debate has led to different conclusions across different areas of psychology. Longitudinal data and up-to-date statistical models have recently indicated that self-esteem has stable and autoregressive trait-like components and state-like components. We applied latent STARTS models with the goal of replicating previous findings in a longitudinal sample of young adults (N = 4,532; Mage = 19.60, SD = 0.85; 55% female). In addition, we applied multigroup models to extend previous findings on different patterns of stability for men versus women and for people with high versus low levels of depressive symptoms. We found evidence for the general pattern of a major proportion of stable and autoregressive trait variance and a smaller yet substantial amount of state variance in self-esteem across 10 years. Furthermore, multigroup models suggested substantial differences in the variance components: Females showed more state variability than males. Individuals with higher levels of depressive symptoms showed more state and less autoregressive trait variance in self-esteem. Results are discussed with respect to the ongoing trait-state debate and possible implications of the group differences that we found in the stability of self-esteem. © 2015 Wiley Periodicals, Inc.
LOCAL POPULATION CHANGE AND VARIATIONS IN RACIAL INTEGRATION IN THE UNITED STATES, 2000-2010.
Bellman, Benjamin; Spielman, Seth E; Franklin, Rachel S
2018-03-01
While population growth has been consistently tied to decreasing racial segregation at the metropolitan level in the United States, little work has been done to relate small-scale changes in population size to integration. We address this question through a novel technique that tracks population changes by race and ethnicity for comparable geographies in both 2000 and 2010. Using the Theil Index, we analyze the fifty most populous Metropolitan Statistical Areas in 2010 for changes in multigroup segregation. We classify local areas by their net population change between 2000 and 2010 using a novel unit of analysis based on aggregating census blocks. We find strong evidence that growing parts of rapidly growing metropolitan areas of the United States are crucial to understanding regional differences in segregation that have emerged in past decades. Multigroup segregation declined the most in growing parts of growing metropolitan areas. Comparatively, growing parts of shrinking or stagnant metropolitan areas were less diverse and had smaller declines in segregation. We also find that local areas with shrinking populations had disproportionately high minority representation in 2000 before population loss took place. We conclude that the regional context of population growth or decline has important consequences for the residential mixing of racial groups.
Forde, David R; Baron, Stephen W; Scher, Christine D; Stein, Murray B
2012-01-01
This study examines the psychometric properties of the Childhood Trauma Questionnaire short form (CTQ-SF) with street youth who have run away or been expelled from their homes (N = 397). Internal reliability coefficients for the five clinical scales ranged from .65 to .95. Confirmatory Factor Analysis (CFA) was used to test the five-factor structure of the scales yielding acceptable fit for the total sample. Additional multigroup analyses were performed to consider items by gender. Results provided only evidence of weak factorial invariance. Constrained models showed invariance in configuration, factor loadings, and factor covariances but failed for equality of intercepts. Mean trauma scores for street youth tended to fall in the moderate to severe range on all abuse/neglect clinical scales. Females reported higher levels of abuse and neglect. Prevalence of child maltreatment of individual forms was very high with 98% of street youth reporting one or more forms; 27.4% of males and 48.9% of females reported all five forms. Results of this study support the viability of the CTQ-SF for screening maltreatment in a highly vulnerable street population. Caution is recommended when comparing prevalence estimates for male and female street youth given the failure of the strong factorial multigroup model.
NASA Astrophysics Data System (ADS)
Hananto, R. B.; Kusmayadi, T. A.; Riyadi
2018-05-01
The research aims to identify the critical thinking process of students in solving geometry problems. The geometry problem selected in this study was the building of flat side room (cube). The critical thinking process was implemented to visual, auditory and kinesthetic learning styles. This research was a descriptive analysis research using qualitative method. The subjects of this research were 3 students selected by purposive sampling consisting of visual, auditory, and kinesthetic learning styles. Data collection was done through test, interview, and observation. The results showed that the students' critical thinking process in identifying and defining steps for each learning style were similar in solving problems. The critical thinking differences were seen in enumerate, analyze, list, and self-correct steps. It was also found that critical thinking process of students with kinesthetic learning style was better than visual and auditory learning styles.
Insight Problem Solving: A Critical Examination of the Possibility of Formal Theory
ERIC Educational Resources Information Center
Batchelder, William H.; Alexander, Gregory E.
2012-01-01
This paper provides a critical examination of the current state and future possibility of formal cognitive theory for insight problem solving and its associated "aha!" experience. Insight problems are contrasted with move problems, which have been formally defined and studied extensively by cognitive psychologists since the pioneering…
Jeong, Tchae-Won; Jung, Min-Ju; Lee, Jun-Woo; Kim, Tae-Young
2015-01-01
In the case of the elderly who highly depend on family, serious health problems can be caused due to the reduction of family meals. Therefore, this study aims to suggest the fundamental data for management of cardiovascular disease, one of the major causes of death in elderly Koreans, by investigating the effects of family meal frequency on the risk factors for cardiovascular disease in Korean elderly males and females. The raw data of the Fifth Korea National Health and Nutrition Examination Survey (KNHANES III) were utilized. Data of 1,236 respondents were extracted for analysis regarding anthropometry, blood, blood pressure, nutrients and total energy intake. For collected data, using SPSS 18.0 and Amos 18.0, the mean and standard deviation, and the path coefficient between groups through a multi-group analysis by structural equation model were checked. As family meal frequency increased, triglyceride and fasting blood glucose in Korean elderly males were likely to decrease, which led to conflicting results with those of Korean elderly females. Frequent family meal makes a positive effect on reducing several risk factors for cardiovascular disease in Korean elderly.
Drug Use and Sexually Transmitted Diseases among Female and Male Arrested Youths
Dembo, Richard; Belenko, Steven; Childs, Kristina; Wareham, Jennifer
2009-01-01
Knowledge of the rates and correlates of juvenile offenders’ sexually transmitted diseases (STD) has been limited to samples of incarcerated youths comprised mostly of males. Data collected on 442 female and 506 male youths processed at a centralized intake facility enabled us to study this important public health problem among a sample of juvenile offenders at the front end of the justice system. Female-male, multi-group latent class analyses identified two subgroups, High Risk and Lower Risk, of youths described by a latent construct of risk based on drug test results, STD test results, and a classification for the seriousness of arrest charge. The results found: (1) a similar classification distinguished High Risk and Lower Risk male and female youths, and (2) important gender group differences in sexual risk related factors (e.g., substance use during sexual encounters). Among the youths in this sample who tested positive for an STD, 66% of the girls and 57% of the boys were released back into the community after arrest. Overall, our findings raise serious public health and social welfare concerns, for both the youths and the community. Prevention and intervention implications of these findings are also discussed. PMID:18979194
NASA Astrophysics Data System (ADS)
Ismail; Suwarsono, St.; Lukito, A.
2018-01-01
Critical thinking is one of the most important skills of the 21st century in addition to other learning skills such as creative thinking, communication skills and collaborative skills. This is what makes researchers feel the need to conduct research on critical thinking skills in junior high school students. The purpose of this study is to describe the critical thinking skills of junior high school female students with high mathematical skills in solving contextual and formal mathematical problems. To achieve this is used qualitative research. The subject of the study was a female student of eight grade junior high school. The students’ critical thinking skills are derived from in-depth problem-based interviews using interview guidelines. Interviews conducted in this study are problem-based interviews, which are done by the subject given a written assignment and given time to complete. The results show that critical thinking skills of female high school students with high math skills are as follows: In solving the problem at the stage of understanding the problem used interpretation skills with sub-indicators: categorization, decode, and clarify meaning. At the planning stage of the problem-solving strategy is used analytical skills with sub-indicators: idea checking, argument identification and argument analysis and evaluation skills with sub indicators: assessing the argument. In the implementation phase of problem solving, inference skills are used with subindicators: drawing conclusions, and problem solving and explanatory skills with sub-indicators: problem presentation, justification procedures, and argument articulation. At the re-checking stage all steps have been employed self-regulatory skills with sub-indicators: self-correction and selfstudy.
Heidari, Mohammad; Shahbazi, Sara
2016-01-01
Background: The aim of this study was to determine the effect of problem-solving training on decision-making skill and critical thinking in emergency medical personnel. Materials and Methods: This study is an experimental study that performed in 95 emergency medical personnel in two groups of control (48) and experimental (47). Then, a short problem-solving course based on 8 sessions of 2 h during the term, was performed for the experimental group. Of data gathering was used demographic and researcher made decision-making and California critical thinking skills questionnaires. Data were analyzed using SPSS software. Results: The finding revealed that decision-making and critical thinking score in emergency medical personnel are low and problem-solving course, positively affected the personnel’ decision-making skill and critical thinking after the educational program (P < 0.05). Conclusions: Therefore, this kind of education on problem-solving in various emergency medicine domains such as education, research, and management, is recommended. PMID:28149823
Problem Solution Project: Transforming Curriculum and Empowering Urban Students and Teachers
ERIC Educational Resources Information Center
Jarrett, Olga S.; Stenhouse, Vera
2011-01-01
This article presents findings of 6 years of implementing a Problem Solution Project, an assignment influenced by service learning, problem-based learning, critical theory, and critical pedagogy whereby teachers help children tackle real problems. Projects of 135 teachers in an urban certification/master's program were summarized by cohort year…
Kong, Ling-Na; Qin, Bo; Zhou, Ying-qing; Mou, Shao-yu; Gao, Hui-Ming
2014-03-01
The objective of this systematic review and meta-analysis was to estimate the effectiveness of problem-based learning in developing nursing students' critical thinking. Searches of PubMed, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Proquest, Cochrane Central Register of Controlled Trials (CENTRAL) and China National Knowledge Infrastructure (CNKI) were undertaken to identify randomized controlled trails from 1965 to December 2012, comparing problem-based learning with traditional lectures on the effectiveness of development of nursing students' critical thinking, with no language limitation. The mesh-terms or key words used in the search were problem-based learning, thinking, critical thinking, nursing, nursing education, nurse education, nurse students, nursing students and pupil nurse. Two reviewers independently assessed eligibility and extracted data. Quality assessment was conducted independently by two reviewers using the Cochrane Collaboration's Risk of Bias Tool. We analyzed critical thinking scores (continuous outcomes) using a standardized mean difference (SMD) or weighted mean difference (WMD) with a 95% confidence intervals (CIs). Heterogeneity was assessed using the Cochran's Q statistic and I(2) statistic. Publication bias was assessed by means of funnel plot and Egger's test of asymmetry. Nine articles representing eight randomized controlled trials were included in the meta-analysis. Most studies were of low risk of bias. The pooled effect size showed problem-based learning was able to improve nursing students' critical thinking (overall critical thinking scores SMD=0.33, 95%CI=0.13-0.52, P=0.0009), compared with traditional lectures. There was low heterogeneity (overall critical thinking scores I(2)=45%, P=0.07) in the meta-analysis. No significant publication bias was observed regarding overall critical thinking scores (P=0.536). Sensitivity analysis showed that the result of our meta-analysis was reliable. Most effect sizes for subscales of the California Critical Thinking Dispositions Inventory (CCTDI) and Bloom's Taxonomy favored problem-based learning, while effect sizes for all subscales of the California Critical Thinking Skills Test (CCTST) and most subscales of the Watson-Glaser Critical Thinking Appraisal (WCGTA) were inconclusive. The results of the current meta-analysis indicate that problem-based learning might help nursing students to improve their critical thinking. More research with larger sample size and high quality in different nursing educational contexts are required. Copyright © 2013 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Byrne, Zinta S.; Felker, Sydney; Vacha-Haase, Tammi; Rickard, Kathryn M.
2011-01-01
Responses from college-age students and those 50 years and older were compared using the Attitudes Toward Women Scale and the Attitudes Toward Feminism Scale. Results from a multigroup confirmatory factor analysis showed groups differed on each scale, suggesting unidimensional scales no longer represent attitudes toward women or feminism.…
ERIC Educational Resources Information Center
Erdogan, Niyazi; Stuessy, Carol
2016-01-01
The most prominent option for finding a solution to the shortage of workers with STEM knowledge has been identified as specialized STEM schools by policymakers in the United States. The current perception of specialized STEM schools can be described as a unique environment that includes advanced curriculum, expert teachers, and opportunities for…
Choi, Eunyoung; Lindquist, Ruth; Song, Yeoungsuk
2014-01-01
Problem-based learning (PBL) is a method widely used in nursing education to develop students' critical thinking skills to solve practice problems independently. Although PBL has been used in nursing education in Korea for nearly a decade, few studies have examined its effects on Korean nursing students' learning outcomes, and few Korean studies have examined relationships among these outcomes. The objectives of this study are to examine outcome abilities including critical thinking, problem-solving, and self-directed learning of nursing students receiving PBL vs. traditional lecture, and to examine correlations among these outcome abilities. A quasi-experimental non-equivalent group pretest-posttest design was used. First-year nursing students (N=90) were recruited from two different junior colleges in two cities (GY and GJ) in South Korea. In two selected educational programs, one used traditional lecture methods, while the other used PBL methods. Standardized self-administered questionnaires of critical thinking, problem-solving, and self-directed learning abilities were administered before and at 16weeks (after instruction). Learning outcomes were significantly positively correlated, however outcomes were not statistically different between groups. Students in the PBL group improved across all abilities measured, while student scores in the traditional lecture group decreased in problem-solving and self-directed learning. Critical thinking was positively associated with problem-solving and self-directed learning (r=.71, and r=.50, respectively, p<.001); problem-solving was positively associated with self-directed learning (r=.75, p<.001). Learning outcomes of PBL were not significantly different from traditional lecture in this small underpowered study, despite positive trends. Larger studies are recommended to study effects of PBL on critical student abilities. Copyright © 2013 Elsevier Ltd. All rights reserved.
Student’s Critical Thinking in Solving Open-Ended Problems Based on Their Personality Type
NASA Astrophysics Data System (ADS)
Fitriana, L. D.; Fuad, Y.; Ekawati, R.
2018-01-01
Critical thinking plays an important role for students in solving open-ended problems. This research aims at describing student’s critical thinking in solving open-ended problems based on Keirsey’s personality types, namely rational, idealist, guardian, and artisan. Four students, with the higher rank in the mathematics’ test and representing each type of Keirsey personality, were selected as the research subjects. The data were collected from the geometry problem and interviews. The student’s critical thinking is described based on the FRISCO criteria. The result underlines that rational and idealist students fulfilled all FRISCO criteria, and but not for guardian and artisan students. Related to the inference criteria, guardian and artisan students could not make reasonable conclusions and connect the concepts. Related to the reason of criteria, rational student performed critical thinking by providing logical reason that supported his strategy to solve the problem. In contrast, the idealist student provided subjective reason. This results suggest that teachers should frequently train the students’ logical thinkingin every lesson and activity to develop student’s critical thinking and take the student’s personality character into account, especially for guardian and artisan students.
Gaebelein, Claude J.; Grice, Gloria R.; Crannage, Andrew J.; Weck, Margaret A.; Hurd, Peter; Walter, Brenda; Duncan, Wendy
2013-01-01
Objective. To determine the feasibility of using a validated set of assessment rubrics to assess students’ critical-thinking and problem-solving abilities across a doctor of pharmacy (PharmD) curriculum. Methods. Trained faculty assessors used validated rubrics to assess student work samples for critical-thinking and problem-solving abilities. Assessment scores were collected and analyzed to determine student achievement of these 2 ability outcomes across the curriculum. Feasibility of the process was evaluated in terms of time and resources used. Results. One hundred sixty-one samples were assessed for critical thinking, and 159 samples were assessed for problem-solving. Rubric scoring allowed assessors to evaluate four 5- to 7-page work samples per hour. The analysis indicated that overall critical-thinking scores improved over the curriculum. Although low yield for problem-solving samples precluded meaningful data analysis, it was informative for identifying potentially needed curricular improvements. Conclusions. Use of assessment rubrics for program ability outcomes was deemed authentic and feasible. Problem-solving was identified as a curricular area that may need improving. This assessment method has great potential to inform continuous quality improvement of a PharmD program. PMID:24159207
Gleason, Brenda L; Gaebelein, Claude J; Grice, Gloria R; Crannage, Andrew J; Weck, Margaret A; Hurd, Peter; Walter, Brenda; Duncan, Wendy
2013-10-14
To determine the feasibility of using a validated set of assessment rubrics to assess students' critical-thinking and problem-solving abilities across a doctor of pharmacy (PharmD) curriculum. Trained faculty assessors used validated rubrics to assess student work samples for critical-thinking and problem-solving abilities. Assessment scores were collected and analyzed to determine student achievement of these 2 ability outcomes across the curriculum. Feasibility of the process was evaluated in terms of time and resources used. One hundred sixty-one samples were assessed for critical thinking, and 159 samples were assessed for problem-solving. Rubric scoring allowed assessors to evaluate four 5- to 7-page work samples per hour. The analysis indicated that overall critical-thinking scores improved over the curriculum. Although low yield for problem-solving samples precluded meaningful data analysis, it was informative for identifying potentially needed curricular improvements. Use of assessment rubrics for program ability outcomes was deemed authentic and feasible. Problem-solving was identified as a curricular area that may need improving. This assessment method has great potential to inform continuous quality improvement of a PharmD program.
A multi-group and preemptable scheduling of cloud resource based on HTCondor
NASA Astrophysics Data System (ADS)
Jiang, Xiaowei; Zou, Jiaheng; Cheng, Yaodong; Shi, Jingyan
2017-10-01
Due to the features of virtual machine-flexibility, easy controlling and various system environments, more and more fields utilize the virtualization technology to construct the distributed system with the virtual resources, also including high energy physics. This paper introduce a method used in high energy physics that supports multiple resource group and preemptable cloud resource scheduling, combining virtual machine with HTCondor (a batch system). It makes resource controlling more flexible and more efficient and makes resource scheduling independent of job scheduling. Firstly, the resources belong to different experiment-groups, and the type of user-groups mapping to resource-groups(same as experiment-group) is one-to-one or many-to-one. In order to make the confused group simply to be managed, we designed the permission controlling component to ensure that the different resource-groups can get the suitable jobs. Secondly, for the purpose of elastically allocating resources for suitable resource-group, it is necessary to schedule resources like scheduling jobs. So this paper designs the cloud resource scheduling to maintain a resource queue and allocate an appropriate amount of virtual resources to the request resource-group. Thirdly, in some kind of situations, because of the resource occupied for a long time, resources need to be preempted. This paper adds the preemption function for the resource scheduling that implement resource preemption based on the group priority. Additionally, the way to preempting is soft that when virtual resources are preempted, jobs will not be killed but also be held and rematched later. It is implemented with the help of HTCondor, storing the held job information in scheduler, releasing the job to idle status and doing second matcher. In IHEP (institute of high energy physics), we have built a batch system based on HTCondor with a virtual resources pool based on Openstack. And this paper will show some cases of experiment JUNO and LHAASO. The result indicates that multi-group and preemptable resource scheduling is efficient to support multi-group and soft preemption. Additionally, the permission controlling component has been used in the local computing cluster, supporting for experiment JUNO, CMS and LHAASO, and the scale will be expanded to more experiments at the first half year, including DYW, BES and so on. Its evidence that the permission controlling is efficient.
Including Critical Thinking and Problem Solving in Physical Education
ERIC Educational Resources Information Center
Pill, Shane; SueSee, Brendan
2017-01-01
Many physical education curriculum frameworks include statements about the inclusion of critical inquiry processes and the development of creativity and problem-solving skills. The learning environment created by physical education can encourage or limit the application and development of the learners' cognitive resources for critical and creative…
Assari, Shervin; Nikahd, Amirmasoud; Malekahmadi, Mohammad Reza; Lankarani, Maryam Moghani; Zamanian, Hadi
2016-10-17
Despite the existing literature on the central role of socioeconomic status (SES; education and income) for maintaining health, less is known about group differences in this effect. Built on the intersectionality approach, this study compared race by gender groups for the effects of baseline education and income on sustained health problems in five domains: depressive symptoms, insomnia, physical inactivity, body mass index (BMI), and self-rated health (SRH). Data came from waves 7, 8, and 10 of the Health and Retirement Study (HRS), which were collected in 2004, 2006, and 2010, respectively. The study followed 37,495 white and black men and women above age 50 for up to 6 years. This number included 12,495 white men, 15,581 white women, 3839 black men, and 5580 black women. Individuals reported their depressive symptoms (Center for Epidemiological Studies-Depression (CES-D) 11), insomnia, physical inactivity, BMI, and SRH across all waves. Multigroup structural equation modeling (SEM) was used to compare black men, black women, white men, and white women for the effects of education and income in 2004 on sustained health problems from 2004 to 2010. In the pooled sample, higher education and income at baseline were associated with lower sustained health problems across all five domains. However, race by gender group differences were found in the effects of education and income on sustained insomnia, physical inactivity, and BMI, but not depressive symptoms and SRH. The protective effects of education against insomnia, physical inactivity, and BMI were not found for black men. For black women, the effect of education on BMI was not found. Income had a protective effect against sustained high BMI among white and black women but not white and black men. The intersection of race and gender alters the protective effects of social determinants on sustained health problems such as insomnia, physical inactivity, and BMI. Social groups particularly vary in the operant mechanisms by which SES contributes to maintaining health over time. The health effects are less universal for education than income. Race by gender groups differ more in SES determinants of BMI, insomnia, and physical inactivity than depressive symptoms and SRH.
Metacognition: Student Reflections on Problem Solving
ERIC Educational Resources Information Center
Wismath, Shelly; Orr, Doug; Good, Brandon
2014-01-01
Twenty-first century teaching and learning focus on the fundamental skills of critical thinking and problem solving, creativity and innovation, and collaboration and communication. Metacognition is a crucial aspect of both problem solving and critical thinking, but it is often difficult to get students to engage in authentic metacognitive…
NASA Astrophysics Data System (ADS)
Leclaire, N.; Cochet, B.; Le Dauphin, F. X.; Haeck, W.; Jacquet, O.
2014-06-01
The present paper aims at providing experimental validation for the use of the MORET 5 code for advanced concepts of reactor involving thorium and heavy water. It therefore constitutes an opportunity to test and improve the thermal-scattering data of heavy water and also to test the recent implementation of probability tables in the MORET 5 code.
The POPOP4 library and codes for preparing secondary gamma-ray production cross sections
NASA Technical Reports Server (NTRS)
Ford, W. E., III
1972-01-01
The POPOP4 code for converting secondary gamma ray yield data to multigroup secondary gamma ray production cross sections and the POPOP4 library of secondary gamma ray yield data are described. Recent results of the testing of uranium and iron data sets from the POPOP4 library are given. The data sets were tested by comparing calculated secondary gamma ray pulse height spectra measured at the ORNL TSR-II reactor.
Vaz, Sharmila; Falkmer, Marita; Parsons, Richard; Passmore, Anne Elizabeth; Parkin, Timothy; Falkmer, Torbjörn
2014-01-01
The relationship between school belongingness and mental health functioning before and after the primary-secondary school transition has not been previously investigated in students with and without disabilities. This study used a prospective longitudinal design to test the bi-directional relationships between these constructs, by surveying 266 students with and without disabilities and their parents, 6-months before and after the transition to secondary school. Cross-lagged multi-group analyses found student perception of belongingness in the final year of primary school to contribute to change in their mental health functioning a year later. The beneficial longitudinal effects of school belongingness on subsequent mental health functioning were evident in all student subgroups; even after accounting for prior mental health scores and the cross-time stability in mental health functioning and school belongingness scores. Findings of the current study substantiate the role of school contextual influences on early adolescent mental health functioning. They highlight the importance for primary and secondary schools to assess students' school belongingness and mental health functioning and transfer these records as part of the transition process, so that appropriate scaffolds are in place to support those in need. Longer term longitudinal studies are needed to increase the understanding of the temporal sequencing between school belongingness and mental health functioning of all mainstream students.
Godoy-Izquierdo, Débora; Guevara, Nicolás Mendoza Ladrón de; Toral, Mercedes Vélez; Galván, Carlos de Teresa; Ballesteros, Alberto Salamanca; García, Juan F Godoy
2017-08-01
This study explored the multidimensional outcomes that resulted from the adherence to regular exercise among previously sedentary postmenopausal women. The exercise was managed through a supervised, multicomponent, adapted approximately 20-week program in a suited health promotion intervention. A multigroup, mixed-design study with between-group (intervention, sedentary, and active women) and within-subject measures (baseline, postintervention, and 3- and 12-month follow-ups) was conducted using intention-to-treat methodology. The Cervantes Scale assessed health-related quality of life (HRQoL), and several indicators of cardio-metabolic status and fitness were also assessed. After the intervention, the participants experienced positive changes in short and long-term physical and mental health, with significant enhancements in several HRQoL dimensions, particularly mental well-being and menopause-related health and subdomains. Improvements were maintained or continued (eg, mental well-being) throughout the period, leading up to the 12-month follow-up. These outcomes were accompanied by significant improvements in cardio-metabolic status and fitness, including weight, body mass index, cardio-respiratory fitness, and flexibility. Our findings parallel previous empirical evidence showing the benefits associated with regular exercise, and add evidence to the association of positive outcomes in HRQoL with improvements in cardio-metabolic health and fitness status after the adoption of an active lifestyle.
Pendergast, Laura L; von der Embse, Nathaniel; Kilgus, Stephen P; Eklund, Katie R
2017-02-01
Evidence-based interventions (EBIs) have become a central component of school psychology research and practice, but EBIs are dependent upon the availability and use of evidence-based assessments (EBAs) with diverse student populations. Multi-group confirmatory factor analysis (MG-CFA) is an analytical tool that can be used to examine the validity and measurement equivalence/invariance of scores across diverse groups. The objective of this article is to provide a conceptual and procedural overview of categorical MG-CFA, as well as an illustrated example based on data from the Social and Academic Behavior Risk Screener (SABRS) - a tool designed for use in school-based interventions. This article serves as a non-technical primer on the topic of MG-CFA with ordinal (rating scale) data and does so through the framework of examining equivalence of measures used for EBIs within multi-tiered models - an understudied topic. To go along with the illustrated example, we have provided supplementary files that include sample data, Mplus input code, and an annotated guide for understanding the input code (http://dx.doi.org/10.1016/j.jsp.2016.11.002). Data needed to reproduce analyses in this article are available as supplemental materials (online only) in the Appendix of this article. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.
Cross-cultural examination of measurement invariance of the Beck Depression Inventory-II.
Dere, Jessica; Watters, Carolyn A; Yu, Stephanie Chee-Min; Bagby, R Michael; Ryder, Andrew G; Harkness, Kate L
2015-03-01
Given substantial rates of major depressive disorder among college and university students, as well as the growing cultural diversity on many campuses, establishing the cross-cultural validity of relevant assessment tools is important. In the current investigation, we examined the Beck Depression Inventory-Second Edition (BDI-II; Beck, Steer, & Brown, 1996) among Chinese-heritage (n = 933) and European-heritage (n = 933) undergraduates in North America. The investigation integrated 3 distinct lines of inquiry: (a) the literature on cultural variation in depressive symptom reporting between people of Chinese and Western heritage; (b) recent developments regarding the factor structure of the BDI-II; and (c) the application of advanced statistical techniques to the issue of cross-cultural measurement invariance. A bifactor model was found to represent the optimal factor structure of the BDI-II. Multigroup confirmatory factor analysis showed that the BDI-II had strong measurement invariance across both culture and gender. In group comparisons with latent and observed variables, Chinese-heritage students scored higher than European-heritage students on cognitive symptoms of depression. This finding deviates from the commonly held view that those of Chinese heritage somatize depression. These findings hold implications for the study and use of the BDI-II, highlight the value of advanced statistical techniques such as multigroup confirmatory factor analysis, and offer methodological lessons for cross-cultural psychopathology research more broadly. 2015 APA, all rights reserved
Williams, Monnica T; Duque, Gerardo; Wetterneck, Chad T; Chapman, L Kevin; DeLapp, Ryan C T
2018-04-01
Prior research has found that a strong positive ethnic identity is a protective factor against anxiety and depression in African Americans. In this study, ethnic identity is examined in a geographically representative sample of African American young adults (n = 242), using the Multigroup Ethnic Identity Measure (MEIM) (Phinney in J Adolescent Res 7:156-76, 15). The two-factor structure of the measure (Roberts et al. in J Early Adolescence 19:301-22, 1) was analyzed using a structural equation model and displayed an acceptable fit only when multiple error terms were correlated. A multigroup confirmatory factor analysis revealed measurement equivalence of the two-factor structure between African Americans from Southern and non-Southern regions of the USA. We found that significantly higher levels of ethnic identity were present among African American in the South compared to other regions, and region significantly predicted total ethnic identity scores in a linear regression, even when controlling for gender, age, urbanicity, and years of education. Furthermore, among African Americans, living in the South was significantly correlated with less help-seeking for diagnosed depression, anxiety, and/or obsessive-compulsive disorder, where help-seeking was defined as obtaining a diagnosis by a professional. The role of ethnic identity and social support are discussed in the context of African American mental health.
Vaz, Sharmila; Falkmer, Marita; Parsons, Richard; Passmore, Anne Elizabeth; Parkin, Timothy; Falkmer, Torbjörn
2014-01-01
The relationship between school belongingness and mental health functioning before and after the primary-secondary school transition has not been previously investigated in students with and without disabilities. This study used a prospective longitudinal design to test the bi-directional relationships between these constructs, by surveying 266 students with and without disabilities and their parents, 6-months before and after the transition to secondary school. Cross-lagged multi-group analyses found student perception of belongingness in the final year of primary school to contribute to change in their mental health functioning a year later. The beneficial longitudinal effects of school belongingness on subsequent mental health functioning were evident in all student subgroups; even after accounting for prior mental health scores and the cross-time stability in mental health functioning and school belongingness scores. Findings of the current study substantiate the role of school contextual influences on early adolescent mental health functioning. They highlight the importance for primary and secondary schools to assess students’ school belongingness and mental health functioning and transfer these records as part of the transition process, so that appropriate scaffolds are in place to support those in need. Longer term longitudinal studies are needed to increase the understanding of the temporal sequencing between school belongingness and mental health functioning of all mainstream students. PMID:24967580
Multi-Group Reductions of LTE Air Plasma Radiative Transfer in Cylindrical Geometries
NASA Technical Reports Server (NTRS)
Scoggins, James; Magin, Thierry Edouard Bertran; Wray, Alan; Mansour, Nagi N.
2013-01-01
Air plasma radiation in Local Thermodynamic Equilibrium (LTE) within cylindrical geometries is studied with an application towards modeling the radiative transfer inside arc-constrictors, a central component of constricted-arc arc jets. A detailed database of spectral absorption coefficients for LTE air is formulated using the NEQAIR code developed at NASA Ames Research Center. The database stores calculated absorption coefficients for 1,051,755 wavelengths between 0.04 µm and 200 µm over a wide temperature (500K to 15 000K) and pressure (0.1 atm to 10.0 atm) range. The multi-group method for spectral reduction is studied by generating a range of reductions including pure binning and banding reductions from the detailed absorption coefficient database. The accuracy of each reduction is compared to line-by-line calculations for cylindrical temperature profiles resembling typical profiles found in arc-constrictors. It is found that a reduction of only 1000 groups is sufficient to accurately model the LTE air radiation over a large temperature and pressure range. In addition to the reduction comparison, the cylindrical-slab formulation is compared with the finite-volume method for the numerical integration of the radiative flux inside cylinders with varying length. It is determined that cylindrical-slabs can be used to accurately model most arc-constrictors due to their high length to radius ratios.
Limbers, Christine A; Newman, Daniel A; Varni, James W
2008-07-01
The objective of the present study was to examine the factorial invariance of the PedsQL 4.0 Generic Core Scales for child self-report across 11,433 children ages 5-18 with chronic health conditions and healthy children. Multigroup Confirmatory Factor Analysis was performed specifying a five-factor model. Two multigroup structural equation models, one with constrained parameters and the other with unconstrained parameters, were proposed in order to compare the factor loadings across children with chronic health conditions and healthy children. Metric invariance (i.e., equal factor loadings) was demonstrated based on stability of the Comparative Fit Index (CFI) between the two models, and several additional indices of practical fit including the root mean squared error of approximation, the Non-normed Fit Index, and the Parsimony Normed Fit Index. The findings support an equivalent five-factor structure on the PedsQL 4.0 Generic Core Scales across healthy and chronic health condition groups. These findings suggest that when differences are found across chronic health condition and healthy groups when utilizing the PedsQL, these differences are more likely real differences in self-perceived health-related quality of life, rather than differences in interpretation of the PedsQL items as a function of health status.
de Jong, Martijn G; Pieters, Rik; Stremersch, Stefan
2012-09-01
Answers to sensitive questions are prone to social desirability bias. If not properly addressed, the validity of the research can be suspect. This article presents multigroup item randomized response theory (MIRRT) to measure self-reported sensitive topics across cultures. The method was specifically developed to reduce social desirability bias by making an a priori change in the design of the survey. The change involves the use of a randomization device (e.g., a die) that preserves participants' privacy at the item level. In cases where multiple items measure a higher level theoretical construct, the researcher could still make inferences at the individual level. The method can correct for under- and overreporting, even if both occur in a sample of individuals or across nations. We present and illustrate MIRRT in a nontechnical manner, provide WinBugs software code so that researchers can directly implement it, and present 2 cross-national studies in which it was applied. The first study compared nonstudent samples from 2 countries (total n = 927) on permissive sexual attitudes and risky sexual behavior and related these to individual-level characteristics such as the Big Five personality traits. The second study compared nonstudent samples from 17 countries (total n = 6,195) on risky sexual behavior and related these to individual-level characteristics, such as gender and age, and to country-level characteristics, such as sex ratio.
Wicked Problems in Special and Inclusive Education
ERIC Educational Resources Information Center
Armstrong, David
2017-01-01
This special paper provides a critical overview of wicked problems in special and inclusive education. Practically, this paper provides a strategic framework for future special issues in the "Journal of Special Educational Needs". Critical attention is also given to the concept of a wicked problem when applied to research in special and…
Inquiry and Critical Thinking in an Elementary Art Program
ERIC Educational Resources Information Center
Lampert, Nancy
2013-01-01
Critical thinking is thought-focused on how to solve a well-defined problem when several alternatives solutions to the problem exist. Because critical thinking may help to build tolerance toward others, the author believes it is a worthwhile subject to investigate, given that people are living in an increasingly multicultural society full of…
Development of Critical Thinking with Metacognitive Regulation and Toulmin Model
ERIC Educational Resources Information Center
Gotoh, Yasushi
2017-01-01
Developing critical thinking is an important factor in education. In this study, the author defines critical thinking as the set of skills and dispositions which enable one to solve problems logically and to attempt to reflect autonomously by means of metacognitive regulation of one's own problem-solving processes. To identify the validity and…
Critical Understanding: The Powers and Limits of Pluralism.
ERIC Educational Resources Information Center
Booth, Wayne C.
The problems created by the competing claims of various schools of criticism for a unified view of meaning are examined in this book. Chapters deal with the following topics: the problem of the plurality of modes, Ronald Crane and the pluralism of discrete modes, Kenneth Burke's multiplication of perspectives, history as criticism and the…
How To Save the World: Through Critical Thinking.
ERIC Educational Resources Information Center
Hanford, George H.
Education is the best hope for peace and progress in the world, and because education is best given and received when infused with critical thinking, critical thinking can save the world. Some of the most serious problems facing humankind are overpopulation and famine. The problems of ethnicity, colonialism, and religion further complicate matters…
ERIC Educational Resources Information Center
Friede, Curtis R.; Irani, Tracy A.; Rhoades, Emily B.; Fuhrman, Nicholas E.; Gallo, Maria
2008-01-01
This study was conducted to examine the statistical relationship between problem solving and critical thinking to guide future teaching and research for agricultural educators using the problem-solving approach. Students enrolled in an undergraduate genetics course in the College of Agricultural and Life Sciences at the University of Florida were…
ERIC Educational Resources Information Center
Rasiman
2015-01-01
This research aims to determine the leveling of critical thinking abilities of students of mathematics education in mathematical problem solving. It includes qualitative-explorative study that was conducted at University of PGRI Semarang. The generated data in the form of information obtained problem solving question and interview guides. The…
ERIC Educational Resources Information Center
Pride, Richard A.
1995-01-01
Focuses on the process by which a social problem is redefined in response to a critical events, such as economic depressions, environmental disasters, intense physical confrontations, or strategic initiatives by a social movement organization. Examines a conservative movement's attempt to redefine "the problem" of the schools at the time…
Problem-Based Learning Pedagogy Fosters Students' Critical Thinking about Writing
ERIC Educational Resources Information Center
Kumar, Rita; Refaei, Brenda
2017-01-01
Convinced of the power of PBL to promote students' critical thinking as demonstrated by its application across disciplines, we designed a series of problems for students in a second-year writing course. We collected samples of their writing before and after implementation of the problems. We were concerned about whether PBL pedagogy would…
NASA Astrophysics Data System (ADS)
Ismail
2018-01-01
This study aims to describe student’s critical thinking skill of grade VIII in solving mathematical problem. A qualitative research was conducted to a male student with high mathematical ability. Student’s critical thinking skill was obtained from a depth task-based interview. The result show that male student’s critical thinking skill of the student as follows. In understanding the problem, the student did categorization, significance decoding, and meaning clarification. In devising a plan he examined his ideas, detected his argument, analyzed his argument and evaluated his argument. During the implementation phase, the skill that appeared were analyzing of the argument and inference skill such as drawing conclusion, deliver alternative thinking, and problem solving skills. At last, in rechecking all the measures, they did self-correcting and self-examination.
Korte, Jojanneke; Bohlmeijer, Ernst T; Westerhof, Gerben J; Pot, Anne Margriet; Pot, Anne M
2011-07-01
The role of reminiscence as a way of adapting to critical life events and chronic medical conditions was investigated in older adults with mild to moderate depressive symptoms. Reminiscence is the (non)volitional act or process of recollecting memories of one's self in the past. 171 Dutch older adults with a mean age of 64 years (SD = 7.4) participated in this study. All of them had mild to moderate depressive symptoms. Participants completed measures on critical life events, chronic medical conditions, depressive symptoms, symptoms of anxiety and satisfaction with life. The reminiscence functions included were: identity, problem solving, bitterness revival and boredom reduction. Critical life events were positively correlated with identity and problem solving. Bitterness revival and boredom reduction were both positively correlated with depressive and anxiety symptoms, and negatively to satisfaction with life. Problem solving had a negative relation with anxiety symptoms. When all the reminiscence functions were included, problem solving was uniquely associated with symptoms of anxiety, and bitterness revival was uniquely associated with depressive symptoms and satisfaction with life. Interestingly, problem solving mediated the relation of critical life events with anxiety. This study corroborates the theory that reminiscence plays a role in coping with critical life events, and thereby maintaining mental health. Furthermore, it is recommended that therapists focus on techniques which reduce bitterness revival in people with depressive symptoms, and focus on problem-solving reminiscences among people with anxiety symptoms.
Development of Critical Thinking with Metacognitive Regulation
ERIC Educational Resources Information Center
Gotoh, Yasushi
2016-01-01
In this research the author defines critical thinking as the set of skills and dispositions which enable one to solve problems logically and to attempt to reflect autonomously by means of Metacognitive regulation on one's own problem-solving processes. In order to develop their critical thinking, it is important for students to be able to use this…
Psychological Predictors of Sexual Intimate Partner Violence against Black and Hispanic Women
Preiser, Brianna
2017-01-01
Background: Although various types of intimate partner violence (IPV) tend to co-occur, risk factors of each type of IPV may differ. At the same time, most of the existing literature on risk factors of IPV among minorities has used a cross-sectional design and has focused on physical rather than sexual IPV. We conducted the current study to compare Black and Hispanic women for psychological predictors of change in sexual IPV over time. Methods: Using data from the Fragile Families and Child Wellbeing Study (FFCWS), this study followed 561 Black and 475 Hispanic women with their male partners for four years. Independent variables included male partners’ depression, anxiety, problem alcohol use, and male-to-female physical and psychological IPV perpetration. The dependent variable was sexual IPV reported by female partners, measured at baseline, two years, and four years later. Covariates included age, income, marital status and education level. We used a multi-group latent growth curve model (LGCM) to explain intercept, linear, and quadratic slopes, which represent the baseline, and linear and curvilinear trajectories of male-to-female sexual IPV, where groups were defined based on ethnicity. Results: Psychological IPV was associated with sexual IPV at baseline among both ethnic groups. The male partner’s depression was a risk factor for an increase in sexual IPV over time among Black but not Hispanic women. Anxiety, problem alcohol use and physical IPV did not have an effect on the baseline or change in sexual IPV over time. Psychological IPV was not associated with an increase in sexual IPV over time in either ethnic group. Conclusions: There is a need for screening of sexual IPV in the presence of psychological IPV among minority women. There is also a need for screening and treatment of male partners’ depression as a strategy to reduce sexual IPV among Black women. Background: Although various types of intimate partner violence (IPV) tend to co-occur, risk factors of each type of IPV may differ. At the same time, most of the existing literature on risk factors of IPV among minorities has used a cross-sectional design and has focused on physical rather than sexual IPV. We conducted the current study to compare Black and Hispanic women for psychological predictors of change in sexual IPV over time. Methods: Using data from the Fragile Families and Child Wellbeing Study (FFCWS), this study followed 561 Black and 475 Hispanic women with their male partners for four years. Independent variables included male partners’ depression, anxiety, problem alcohol use, and male-to-female physical and psychological IPV perpetration. The dependent variable was sexual IPV reported by female partners, measured at baseline, two years, and four years later. Covariates included age, income, marital status and education level. We used a multi-group latent growth curve model (LGCM) to explain intercept, linear, and quadratic slopes, which represent the baseline, and linear and curvilinear trajectories of male-to-female sexual IPV, where groups were defined based on ethnicity. Results: Psychological IPV was associated with sexual IPV at baseline among both ethnic groups. The male partner’s depression was a risk factor for an increase in sexual IPV over time among Black but not Hispanic women. Anxiety, problem alcohol use and physical IPV did not have an effect on the baseline or change in sexual IPV over time. Psychological IPV was not associated with an increase in sexual IPV over time in either ethnic group. Conclusions: There is a need for screening of sexual IPV in the presence of psychological IPV among minority women. There is also a need for screening and treatment of male partners’ depression as a strategy to reduce sexual IPV among Black women. PMID:29280969
Thermal neutron streaming effects and WIMS analysis of the Penn State subcritical graphite pile
DOE Office of Scientific and Technical Information (OSTI.GOV)
Feltus, M.A.; Zediak, C.S.; Jester, W.A.
1997-12-01
This analysis was performed on the Pennsylvania State University (PSU) subcritical reactor to find more accurate values for such nuclear parameters as the thermal fuel utilization factor, thermal diffusion length in the graphite, migration area, k{sub eff}, etc. The analysis involved using the Winfrith Integrated Multigroup Scheme (WIMS) code as well as various hand calculations to find and compare those parameters. The data found in this analysis will be used by future students in the Penn State laboratory courses.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Plelnevaux, C.
The computer program DIFF, in Fortran for the IBM 7090, for calculating the neutron diffusion coefficients and attenuation areas (L/sup 2/) necessary for multigroup diffusion calculations for reactor shielding is described. Diffusion coefficients and values of the inverse attenuation length are given for a six group calculation for several interesting shielding materials. (D.C.W.)
Nuclear Data Uncertainty Propagation to Reactivity Coefficients of a Sodium Fast Reactor
NASA Astrophysics Data System (ADS)
Herrero, J. J.; Ochoa, R.; Martínez, J. S.; Díez, C. J.; García-Herranz, N.; Cabellos, O.
2014-04-01
The assessment of the uncertainty levels on the design and safety parameters for the innovative European Sodium Fast Reactor (ESFR) is mandatory. Some of these relevant safety quantities are the Doppler and void reactivity coefficients, whose uncertainties are quantified. Besides, the nuclear reaction data where an improvement will certainly benefit the design accuracy are identified. This work has been performed with the SCALE 6.1 codes suite and its multigroups cross sections library based on ENDF/B-VII.0 evaluation.
FY15 Status Report on NEAMS Neutronics Activities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, C. H.; Shemon, E. R.; Smith, M. A.
2015-09-30
This report summarizes the current status of NEAMS activities in FY2015. The tasks this year are (1) to improve solution methods for steady-state and transient conditions, (2) to develop features and user friendliness to increase the usability and applicability of the code, (3) to improve and verify the multigroup cross section generation scheme, (4) to perform verification and validation tests of the code using SFRs and thermal reactor cores, and (5) to support early users of PROTEUS and update the user manuals.
Bi-Directional Communication: A Critical Component of HAT
NASA Technical Reports Server (NTRS)
Shively, Robert J.
2016-01-01
Known problems with automation include lack of mode awareness, automation brittleness, and risk of miscalibrated trust. Human-Autonomy Teaming (HAT) is essential for improving these problems. This presentation outlines critical components for Human-Autonomy Teaming.
Life after critical illness: an overview.
Rattray, Janice
2014-03-01
To illustrate the potential physical and psychological problems faced by patients after an episode of critical illness, highlight some of the interventions that have been tested and identify areas for future research. Recovery from critical illness is an international problem and as an issue is likely to increase. For some, recovery from critical illness is prolonged, subject to physical and psychological problems that may negatively impact upon health-related quality of life. The literature accessed for this review includes the work of a number of key researchers in the field of critical care research. These were identified from a number of sources include (1) personal knowledge of the research field accumulated over the last decade and (2) using the search engine 'The Knowledge Network Scotland'. Fatigue and weakness are significant problems for critical care survivors and are common in patients who have been in ICU for more than one week. Psychological problems include anxiety, depression, post-traumatic stress, delirium and cognitive impairment. Prevalence of these problems is difficult to establish for a number of methodological reasons that include the use of self-report questionnaires, the number of different questionnaires used and the variation in administration and timing. Certain subgroups of ICU survivors especially those at the more severe end of the illness severity spectrum are more at risk and this has been demonstrated for both physical and psychological problems. Findings from international studies of a range of potential interventions are presented. However, establishing effectiveness for most of these still has to be empirically demonstrated. What seems clear is the need for a co-ordinated, multidisciplinary, designated recovery and rehabilitation pathway that begins as soon as the patient is admitted into an intensive care unit. © 2013 John Wiley & Sons Ltd.
ERIC Educational Resources Information Center
McGarrity, DeShawn N.
2013-01-01
Society is faced with more complex problems than in the past because of rapid advancements in technology. These complex problems require multi-dimensional problem-solving abilities that are consistent with higher-order thinking skills. Bok (2006) posits that over 90% of U.S. faculty members consider critical thinking skills as essential for…
Critical Problems Facing Technology Education: Perceptions of Indiana Teachers
ERIC Educational Resources Information Center
Lazaros, Edward J.; Rogers, George E.
2006-01-01
In 1993 Wicklein conducted a study to determine the present and the future critical issues and problems facing the technology education (TE) profession. The Wicklein study questioned 25 panelists from 15 states and the District of Columbia to ascertain the issues and problems facing TE. However, in the Wicklein study, only seven of the panelists…
ERIC Educational Resources Information Center
Burris, Scott; Garton, Bryan L.
2007-01-01
The purpose of the study was to determine the effect of problem-based learning (PBL) on critical thinking ability and content knowledge among selected secondary agriculture students in Missouri. The study employed a quasi-experimental, non-equivalent comparison group design. The treatment consisted of two instructional strategies: problem-based…
The Critical Thinking Skills of Teacher Candidates Turkish Republic of Northern Cyprus Sampling
ERIC Educational Resources Information Center
Serin, Oguz
2013-01-01
Problem Statement: The main function of education is to prepare individuals for life. In this context, education aims to equip individuals throughout the different stages of education, where most of the time individuals learn how they should behave, as well as how to manage problems with effective problem-solving and critical thinking skills. The…
NASA Astrophysics Data System (ADS)
Aswan, D. M.; Lufri, L.; Sumarmin, R.
2018-04-01
This research intends to determine the effect of Problem Based Learning models on students' critical thinking skills and competences. This study was a quasi-experimental research. The population of the study was the students of class VIII SMPN 1 Subdistrict Gunuang Omeh. Random sample selection is done by randomizing the class. Sample class that was chosen VIII3 as an experimental class given that treatment study based on problems and class VIII1 as control class that treatment usually given study. Instrument that used to consist of critical thinking test, cognitive tests, observation sheet of affective and psychomotor. Independent t-test and Mann Whitney U test was used for the analysis. Results showed that there was significant difference (sig <0.05) between control and experimental group. The conclusion of this study was Problem Based Learning models affected the students’ critical thinking skills and competences.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Favorite, Jeffrey A.
SENSMG is a tool for computing first-order sensitivities of neutron reaction rates, reaction-rate ratios, leakage, k eff, and α using the PARTISN multigroup discrete-ordinates code. SENSMG computes sensitivities to all of the transport cross sections and data (total, fission, nu, chi, and all scattering moments), two edit cross sections (absorption and capture), and the density for every isotope and energy group. It also computes sensitivities to the mass density for every material and derivatives with respect to all interface locations. The tool can be used for one-dimensional spherical (r) and two-dimensional cylindrical (r-z) geometries. The tool can be used formore » fixed-source and eigenvalue problems. The tool implements Generalized Perturbation Theory (GPT) as discussed by Williams and Stacey. Section II of this report describes the theory behind adjoint-based sensitivities, gives the equations that SENSMG solves, and defines the sensitivities that are output. Section III describes the user interface, including the input file and command line options. Section IV describes the output. Section V gives some notes about the coding that may be of interest. Section VI discusses verification, which is ongoing. Section VII lists needs and ideas for future work. Appendix A lists all of the input files whose results are presented in Sec. VI.« less
Parallel and Portable Monte Carlo Particle Transport
NASA Astrophysics Data System (ADS)
Lee, S. R.; Cummings, J. C.; Nolen, S. D.; Keen, N. D.
1997-08-01
We have developed a multi-group, Monte Carlo neutron transport code in C++ using object-oriented methods and the Parallel Object-Oriented Methods and Applications (POOMA) class library. This transport code, called MC++, currently computes k and α eigenvalues of the neutron transport equation on a rectilinear computational mesh. It is portable to and runs in parallel on a wide variety of platforms, including MPPs, clustered SMPs, and individual workstations. It contains appropriate classes and abstractions for particle transport and, through the use of POOMA, for portable parallelism. Current capabilities are discussed, along with physics and performance results for several test problems on a variety of hardware, including all three Accelerated Strategic Computing Initiative (ASCI) platforms. Current parallel performance indicates the ability to compute α-eigenvalues in seconds or minutes rather than days or weeks. Current and future work on the implementation of a general transport physics framework (TPF) is also described. This TPF employs modern C++ programming techniques to provide simplified user interfaces, generic STL-style programming, and compile-time performance optimization. Physics capabilities of the TPF will be extended to include continuous energy treatments, implicit Monte Carlo algorithms, and a variety of convergence acceleration techniques such as importance combing.
Benchmarking of calculation schemes in APOLLO2 and COBAYA3 for WER lattices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zheleva, N.; Ivanov, P.; Todorova, G.
This paper presents solutions of the NURISP WER lattice benchmark using APOLLO2, TRIPOLI4 and COBAYA3 pin-by-pin. The main objective is to validate MOC based calculation schemes for pin-by-pin cross-section generation with APOLLO2 against TRIPOLI4 reference results. A specific objective is to test the APOLLO2 generated cross-sections and interface discontinuity factors in COBAYA3 pin-by-pin calculations with unstructured mesh. The VVER-1000 core consists of large hexagonal assemblies with 2 mm inter-assembly water gaps which require the use of unstructured meshes in the pin-by-pin core simulators. The considered 2D benchmark problems include 19-pin clusters, fuel assemblies and 7-assembly clusters. APOLLO2 calculation schemes withmore » the step characteristic method (MOC) and the higher-order Linear Surface MOC have been tested. The comparison of APOLLO2 vs. TRIPOLI4 results shows a very close agreement. The 3D lattice solver in COBAYA3 uses transport corrected multi-group diffusion approximation with interface discontinuity factors of Generalized Equivalence Theory (GET) or Black Box Homogenization (BBH) type. The COBAYA3 pin-by-pin results in 2, 4 and 8 energy groups are close to the reference solutions when using side-dependent interface discontinuity factors. (authors)« less
Adolescent Depression and Negative Life Events, the Mediating Role of Cognitive Emotion Regulation
Stikkelbroek, Yvonne; Bodden, Denise H. M.; Kleinjan, Marloes; Reijnders, Mirjam; van Baar, Anneloes L.
2016-01-01
Background Depression during adolescence is a serious mental health problem. Difficulties in regulating evoked emotions after stressful life events are considered to lead to depression. This study examined if depressive symptoms were mediated by various cognitive emotion regulation strategies after stressful life events, more specifically, the loss of a loved one, health threats or relational challenges. Methods We used a sample of 398 adolescents (Mage = 16.94, SD = 2.90), including 52 depressed outpatients, who all reported stressful life event(s). Path analyses in Mplus were used to test mediation, for the whole sample as well as separately for participants scoring high versus low on depression, using multigroup analyses. Results Health threats and relational challenging stressful life events were associated with depressive symptoms, while loss was not. More frequent use of maladaptive strategies was related to more depressive symptoms. More frequent use of adaptive strategies was related to less depressive symptoms. Specific life events were associated with specific emotion regulation strategies. The relationship between challenging, stressful life events and depressive symptoms in the whole group was mediated by maladaptive strategies (self-blame, catastrophizing and rumination). No mediation effect was found for adaptive strategies. Conclusion The association between relational challenging, stressful life events and depressive symptoms was mediated by maladaptive, cognitive emotion regulation strategies. PMID:27571274
Flight control with adaptive critic neural network
NASA Astrophysics Data System (ADS)
Han, Dongchen
2001-10-01
In this dissertation, the adaptive critic neural network technique is applied to solve complex nonlinear system control problems. Based on dynamic programming, the adaptive critic neural network can embed the optimal solution into a neural network. Though trained off-line, the neural network forms a real-time feedback controller. Because of its general interpolation properties, the neurocontroller has inherit robustness. The problems solved here are an agile missile control for U.S. Air Force and a midcourse guidance law for U.S. Navy. In the first three papers, the neural network was used to control an air-to-air agile missile to implement a minimum-time heading-reverse in a vertical plane corresponding to following conditions: a system without constraint, a system with control inequality constraint, and a system with state inequality constraint. While the agile missile is a one-dimensional problem, the midcourse guidance law is the first test-bed for multiple-dimensional problem. In the fourth paper, the neurocontroller is synthesized to guide a surface-to-air missile to a fixed final condition, and to a flexible final condition from a variable initial condition. In order to evaluate the adaptive critic neural network approach, the numerical solutions for these cases are also obtained by solving two-point boundary value problem with a shooting method. All of the results showed that the adaptive critic neural network could solve complex nonlinear system control problems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Risner, J.M.; Wiarda, D.; Miller, T.M.
2011-07-01
The U.S. Nuclear Regulatory Commission's Regulatory Guide 1.190 states that calculational methods used to estimate reactor pressure vessel (RPV) fluence should use the latest version of the evaluated nuclear data file (ENDF). The VITAMIN-B6 fine-group library and BUGLE-96 broad-group library, which are widely used for RPV fluence calculations, were generated using ENDF/B-VI.3 data, which was the most current data when Regulatory Guide 1.190 was issued. We have developed new fine-group (VITAMIN-B7) and broad-group (BUGLE-B7) libraries based on ENDF/B-VII.0. These new libraries, which were processed using the AMPX code system, maintain the same group structures as the VITAMIN-B6 and BUGLE-96 libraries.more » Verification and validation of the new libraries were accomplished using diagnostic checks in AMPX, 'unit tests' for each element in VITAMIN-B7, and a diverse set of benchmark experiments including critical evaluations for fast and thermal systems, a set of experimental benchmarks that are used for SCALE regression tests, and three RPV fluence benchmarks. The benchmark evaluation results demonstrate that VITAMIN-B7 and BUGLE-B7 are appropriate for use in RPV fluence calculations and meet the calculational uncertainty criterion in Regulatory Guide 1.190. (authors)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Risner, Joel M; Wiarda, Dorothea; Miller, Thomas Martin
2011-01-01
The U.S. Nuclear Regulatory Commission s Regulatory Guide 1.190 states that calculational methods used to estimate reactor pressure vessel (RPV) fluence should use the latest version of the Evaluated Nuclear Data File (ENDF). The VITAMIN-B6 fine-group library and BUGLE-96 broad-group library, which are widely used for RPV fluence calculations, were generated using ENDF/B-VI data, which was the most current data when Regulatory Guide 1.190 was issued. We have developed new fine-group (VITAMIN-B7) and broad-group (BUGLE-B7) libraries based on ENDF/B-VII. These new libraries, which were processed using the AMPX code system, maintain the same group structures as the VITAMIN-B6 and BUGLE-96more » libraries. Verification and validation of the new libraries was accomplished using diagnostic checks in AMPX, unit tests for each element in VITAMIN-B7, and a diverse set of benchmark experiments including critical evaluations for fast and thermal systems, a set of experimental benchmarks that are used for SCALE regression tests, and three RPV fluence benchmarks. The benchmark evaluation results demonstrate that VITAMIN-B7 and BUGLE-B7 are appropriate for use in LWR shielding applications, and meet the calculational uncertainty criterion in Regulatory Guide 1.190.« less
ERIC Educational Resources Information Center
Quattrucci, Joseph G.
2018-01-01
A new method for teaching advanced laboratories at the undergraduate level is presented. The intent of this approach is to get students more engaged in the lab experience and apply critical thinking skills to solve problems. The structure of the lab is problem-based and provides students with a research-like experience. Students read the current…
ERIC Educational Resources Information Center
Lim, Leonel
2011-01-01
It is widely held that, by teaching individuals how to reason through and analyse everyday problems, the teaching of critical thinking develops the deliberative capacities essential to the healthy functioning of democracy. Implicit in this view is the assumption that a certain commensurability exists between the problems presented in such…
ERIC Educational Resources Information Center
Ulger, Kani
2018-01-01
The problem-based learning (PBL) approach was implemented as a treatment for higher education visual arts students over one semester to examine its effect on the creative thinking and critical thinking disposition of these students. PBL had a significant effect on creative thinking, but critical thinking disposition was affected to a lesser…
den Brok, Perry; van Tartwijk, Jan; Wubbels, Theo; Veldman, Ietje
2010-06-01
The differential effectiveness of schools and teachers receives a growing interest, but few studies focused on the relevance of student ethnicity for this effectiveness and only a small number of these studies investigated teaching in terms of the teacher-student interpersonal relationship. Furthermore, the methodology employed often restricted researchers to investigating direct effects between variables across large samples of students. This study uses causal modelling to investigate associations between student background characteristics, students' perceptions of the teacher-student interpersonal relationship, and student outcomes, across and within several population subgroups in Dutch secondary multi-ethnic classes. Multi-group structural equation modelling was used to investigate causal paths between variables in four ethnic groups: Dutch (N=387), Turkish first- and second-generation immigrant students (N=267), Moroccan first and second generation (N=364), and Surinamese second-generation students (N=101). Different structural paths were necessary to explain associations between variables in the different (sub) groups. Different amounts of variance in student attitudes could be explained by these variables. The teacher-student interpersonal relationship is more important for students with a non-Dutch background than for students with a Dutch background. Results suggest that the teacher-student relationship is more important for second generation than for first-generation immigrant students. Multi-group causal model analyses can provide a better, more differentiated picture of the associations between student background variables, teacher behaviour, and student outcomes than do more traditional types of analyses.
Ahn, Hyun Seon; Usher, Ellen L; Butz, Amanda; Bong, Mimi
2016-03-01
The potential role of culture in the development and operation of self-efficacy has been acknowledged by researchers. Clearer understanding of this cultural impact will benefit from research that shows how the same efficacy information is evaluated across cultures. We tested whether two sources of self-efficacy information delivered by multiple social agents (i.e., vicarious experience and social persuasion) were weighed differently by adolescents in different cultures. Of 2,893 middle school students in Korea (n = 416), the Philippines (n = 522), and the United States (n = 1,955) who completed the survey, 400 students were randomly pooled from each country. Invariance of the measurement and of the latent means for self-efficacy and self-efficacy sources across the groups was tested by multigroup confirmatory factor analysis. Predictive utility of the self-efficacy sources was compared by multigroup structural equation modelling. Compared to the students in the two collectivistic countries, the US students reported significantly higher mathematics self-efficacy. Whereas the efficacy beliefs of the Korean and the US students were predicted equally well by the vicarious experience from their teachers and the social persuasion by their family and peers, those of the Filipino adolescents were best predicted by the social persuasion from their peers. This study provided empirical evidence that socially conveyed sources of self-efficacy information are construed and evaluated differently across cultures, depending on who delivered the efficacy-relevant information. © 2015 The British Psychological Society.
Mak, Kwok-Kei; Lai, Ching-Man
2012-06-01
The psychometric properties of the Revised Restraint Scale (RRS) have been well established in western populations but not in Chinese adolescents. This study investigated the psychometric properties of RRS and its validity in different subgroups for Hong Kong Chinese adolescents. In 2007, 909 Hong Kong students aged 12 to 18 years (55.3% boys) completed a questionnaire including demographic items, RRS, Eating Attitudes Test (EAT-26), and Motivation for Eating Scale (MFES)-physical. Moreover, subjects' height and weight were measured. To examine the factor structure of RRS, the whole sample was randomly split into two groups (sample 1: N=454 and sample 2: N=455) for exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), respectively. Convergent and discriminant validity of RRS were investigated by correlating the RRS with EAT-26 and MFES-physical. Multigroup CFA was conducted to test the three-factor model of RRS in different sex, age, and weight status subgroups. Results of EFA for sample 1 revealed three strongly correlated factors for the RRS construct, and were supported by the CFA results in sample 2. Multigroup CFA further suggested that the three-factor model of RRS was stable across sex, age, and weight status subgroups. A new three-factor model is proposed for Hong Kong adolescents in this study. In general, RRS is a reliable and valid measure of restrained eating for adolescents, regardless of sex, age, and weight status.
Hong, Yong-Rock; Holcomb, Derek; Ballard, Michael; Schwartz, Laurel
Winds of change have been blowing in the U.S. healthcare system since passage of the Affordable Care Act. Examining differences between individuals covered by different types of insurance is essential if healthcare executives are to develop new strategies in response to the emerging health insurance market. In this study, we used multigroup path analysis models to examine the moderating effects of health insurance on direct and indirect associations with general health status, satisfaction with received care, financial burden, and perceived value of the healthcare system. Data were obtained from the 2012 Medical Expenditure Panel Survey and analyzed according to the types of insurance: private, public, and military. With the satisfactory fit of the model (χ = 2,532.644, df = 96, p < .001; normed fit index = 0.943; incremental fit index = 0.945; comparative fit index = 0.957; root mean squared error of approximation = 0.044), higher healthcare quality was positively associated with better health status, greater satisfaction, and greater perceived value of the healthcare system in the three insurance groups. In addition, although all direct paths between health service quality and financial burden were not statistically significant, indirect effects were significant in all models through health status. Being married and earning higher incomes were also found to be strong predictors of better health status and health service quality. Efforts to improve the quality of health services are needed, which could contribute to a reduction in health disparities among insurance beneficiaries and result in less healthcare spending.
Ruffing, Stephanie; Wach, F. -Sophie; Spinath, Frank M.; Brünken, Roland; Karbach, Julia
2015-01-01
Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by correlation analyses. A set of t-tests was used to test for gender differences in learning strategies, whereas structural equation modeling as well as multi-group analyses were applied to investigate the incremental contribution of learning strategies for male and female students’ academic performance. The sample consisted of 461 students (mean age = 21.2 years, SD = 3.2). Correlation analyses revealed that general cognitive ability as well as the learning strategies effort, attention, and learning environment were positively correlated with academic achievement. Gender differences were found in the reported application of many learning strategies. Importantly, the prediction of achievement in structural equation modeling revealed that only effort explained incremental variance (10%) over general cognitive ability. Results of multi-group analyses showed no gender differences in this prediction model. This finding provides further knowledge regarding gender differences in learning research and the specific role of learning strategies for academic achievement. The incremental assessment of learning strategy use as well as gender-differences in their predictive value contributes to the understanding and improvement of successful academic development. PMID:26347698
NASA Astrophysics Data System (ADS)
Pescarini, Massimo; Orsi, Roberto; Frisoni, Manuela
2017-09-01
The ENEA-Bologna Nuclear Data Group produced the VITJEFF32.BOLIB multi-group coupled neutron/photon (199 n + 42 γ) cross section library in AMPX format, based on the OECD-NEA Data Bank JEFF-3.2 evaluated nuclear data library. VITJEFF32.BOLIB was conceived for nuclear fission applications as European counterpart of the ORNL VITAMIN-B7 similar library (ENDF/B-VII.0 data). VITJEFF32.BOLIB has the same neutron and photon energy group structure as the former ORNL VITAMIN-B6 reference library (ENDF/B-VI.3 data) and was produced using similar data processing methodologies, based on the LANL NJOY-2012.53 nuclear data processing system for the generation of the nuclide cross section data files in GENDF format. Then the ENEA-Bologna 2007 Revision of the ORNL SCAMPI nuclear data processing system was used for the conversion into the AMPX format. VITJEFF32.BOLIB contains processed cross section data files for 190 nuclides, obtained through the Bondarenko (f-factor) method for the treatment of neutron resonance self-shielding and temperature effects. Collapsed working libraries of self-shielded cross sections in FIDO-ANISN format, used by the deterministic transport codes of the ORNL DOORS system, can be generated from VITJEFF32.BOLIB through the cited SCAMPI version. This paper describes the methodology and specifications of the data processing performed and presents some results of the VITJEFF32.BOLIB validation.
Ruffing, Stephanie; Wach, F-Sophie; Spinath, Frank M; Brünken, Roland; Karbach, Julia
2015-01-01
Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by correlation analyses. A set of t-tests was used to test for gender differences in learning strategies, whereas structural equation modeling as well as multi-group analyses were applied to investigate the incremental contribution of learning strategies for male and female students' academic performance. The sample consisted of 461 students (mean age = 21.2 years, SD = 3.2). Correlation analyses revealed that general cognitive ability as well as the learning strategies effort, attention, and learning environment were positively correlated with academic achievement. Gender differences were found in the reported application of many learning strategies. Importantly, the prediction of achievement in structural equation modeling revealed that only effort explained incremental variance (10%) over general cognitive ability. Results of multi-group analyses showed no gender differences in this prediction model. This finding provides further knowledge regarding gender differences in learning research and the specific role of learning strategies for academic achievement. The incremental assessment of learning strategy use as well as gender-differences in their predictive value contributes to the understanding and improvement of successful academic development.
Fitzgerald, Amanda; Heary, Caroline; Kelly, Colette; Nixon, Elizabeth; Shevlin, Mark
2013-04-01
Adolescence, with its change in dietary habits, is likely to be a vulnerable period in the onset of obesity. It is considered that peers have an important role to play on adolescents' diet, however, limited research has examined the role of peers in this context. This study examined the relationship between self-efficacy for healthy eating, parent and peer support for healthy and unhealthy eating and food intake patterns. Participants were 264 boys and 219 girls (N=483), aged 13-18years, recruited from post-primary schools in Ireland. Self-report measures assessed self-efficacy, parent and peer support for healthy eating, and for unhealthy eating. Dietary pattern analysis, a popular alternative to traditional methods used in nutritional research, was conducted on a FFQ to derive food intake patterns. Two patterns were identified labelled 'healthy food intake' and 'unhealthy food intake'. Multi-group modelling was used to evaluate whether the hypothesized model of factors related to dietary patterns differed by gender. The multi-group model fit the data well, with only one path shown to differ by gender. Lower self-efficacy for healthy eating and higher peer support for unhealthy eating were associated with 'unhealthy food intake'. Higher self-efficacy was associated with 'healthy food intake'. Prevention programs that target self-efficacy for eating and peer support for unhealthy eating may be beneficial in improving dietary choices among adolescents. Copyright © 2012 Elsevier Ltd. All rights reserved.
Interpersonal problems, dependency, and self-criticism in major depressive disorder.
Dinger, Ulrike; Barrett, Marna S; Zimmermann, Johannes; Schauenburg, Henning; Wright, Aidan G C; Renner, Fritz; Zilcha-Mano, Sigal; Barber, Jacques P
2015-01-01
The goal of the present research was the examination of overlap between 2 research traditions on interpersonal personality traits in major depression. We hypothesized that Blatt's (2004) dimensions of depressive experiences around the dimensions of relatedness (i.e., dependency) and self-definition (i.e., self-criticism) are associated with specific interpersonal problems according to the interpersonal circumplex model (Leary, 1957). In addition, we examined correlations of interpersonal characteristics with depression severity. Analyses were conducted on 283 patients with major depressive disorder combined from 2 samples. Of the patients, 151 participated in a randomized controlled trial in the United States, and 132 patients were recruited in an inpatient unit in Germany. Patients completed measures of symptomatic distress, interpersonal problems, and depressive experiences. Dependency was associated with more interpersonal problems related to low dominance and high affiliation, while self-criticism was associated with more interpersonal problems related to low affiliation. These associations were independent of depression severity. Self-criticism showed high overlap with cognitive symptoms of depression. The findings support the interpersonal nature of Blatt's dimensions of depressive experiences. Self-criticism is associated with being too distant or cold toward others as well as greater depression severity, but is not related to the dimension of dominance. © 2014 Wiley Periodicals, Inc.
Asad, Munazza; Iqbal, Khadija; Sabir, Mohammad
2015-01-01
Problem based learning (PBL) is an instructional approach that utilizes problems or cases as a context for students to acquire problem solving skills. It promotes communication skills, active learning, and critical thinking skills. It encourages peer teaching and active participation in a group. It was a cross-sectional study conducted at Al Nafees Medical College, Isra University, Islamabad, in one month duration. This study was conducted on 193 students of both 1st and 2nd year MBBS. Each PBL consists of three sessions, spaced by 2-3 days. In the first session students were provided a PBL case developed by both basic and clinical science faculty. In Session 2 (group discussion), they share, integrate their knowledge with the group and Wrap up (third session), was concluded at the end. A questionnaire based survey was conducted to find out overall effectiveness of PBL sessions. Teaching through PBLs greatly improved the problem solving and critical reasoning skills with 60% students of first year and 71% of 2nd year agreeing that the acquisition of knowledge and its application in solving multiple choice questions (MCQs) was greatly improved by these sessions. They observed that their self-directed learning, intrinsic motivation and skills to relate basic concepts with clinical reasoning which involves higher order thinking have greatly enhanced. Students found PBLs as an effective strategy to promote teamwork and critical thinking skills. PBL is an effective method to improve critical thinking and problem solving skills among medical students.
Critical Pedagogy's Problem with Changing Teachers' Dispositions towards Critical Teaching
ERIC Educational Resources Information Center
Neumann, Jacob W.
2013-01-01
Increasing teachers' dispositions towards critical teaching is a fundamental goal for critical pedagogy. Because critical educational change cannot occur without teachers' "buy-in," developing teachers' inclination to implement critical teaching into their classrooms is a prerequisite for any successful critical pedagogy…
String theory, quantum phase transitions, and the emergent Fermi liquid.
Cubrović, Mihailo; Zaanen, Jan; Schalm, Koenraad
2009-07-24
A central problem in quantum condensed matter physics is the critical theory governing the zero-temperature quantum phase transition between strongly renormalized Fermi liquids as found in heavy fermion intermetallics and possibly in high-critical temperature superconductors. We found that the mathematics of string theory is capable of describing such fermionic quantum critical states. Using the anti-de Sitter/conformal field theory correspondence to relate fermionic quantum critical fields to a gravitational problem, we computed the spectral functions of fermions in the field theory. By increasing the fermion density away from the relativistic quantum critical point, a state emerges with all the features of the Fermi liquid.
NASA Astrophysics Data System (ADS)
Mosca, Pietro; Mounier, Claude
2016-03-01
The automatic construction of evolution chains recently implemented in GALILEE system is based on the analysis of several ENDF files : the multigroup production cross sections present in the GENDF files processed by NJOY from the ENDF evaluation, the decay file and the fission product yields (FPY) file. In this context, this paper highlights the importance of the nucleus identification to properly interconnect the data mentioned above. The first part of the paper describes the present status of the nucleus identification among the several ENDF files focusing, in particular, on the use of the excited state number and of the isomeric state number. The second part reviews the problems encountered during the automatic construction of the depletion chains using recent ENDF data. The processing of the JEFF-3.1.1, ENDF/B-VII.0 (decay and FPY) and the JEFF-3.2 (production cross section) points out problems about the compliance or not of the nucleus identifiers with the ENDF-6 format and sometimes the inconsistencies among the various ENDF files. In addition, the analysis of EAF-2003 and EAF-2010 shows some incoherence between the ZA product identifier and the reaction identifier MT for the reactions (n, pα) and (n, 2np). As a main result of this work, our suggestion is to change the ENDF format using systematically the isomeric state number to identify the nuclei. This proposal is already compliant to a huge amount ENDF data that are not in agreement with the present ENDF format. This choice is the most convenient because, ultimately, it allows one to give human readable names to the nuclei of the depletion chains.
Identifying critical thinking indicators and critical thinker attributes in nursing practice.
Chao, Shu-Yuan; Liu, Hsing-Yuan; Wu, Ming-Chang; Clark, Mary Jo; Tan, Jung-Ying
2013-09-01
Critical thinking is an essential skill in the nursing process. Although several studies have evaluated the critical thinking skills of nurses, there is limited information related to the indicators of critical thinking or evaluation of critical thinking in the context of the nursing process. This study investigated the potential indicators of critical thinking and the attributes of critical thinkers in clinical nursing practice. Knowledge of these indicators can aid the development of tools to assess nursing students' critical thinking skills. The study was conducted between September 2009 and August 2010. In phase 1, a literature review and four focus groups were conducted to identify the indicators of critical thinking in the context of nursing and the attributes of critical thinkers. In phase 2, 30 nursing professionals participated in a modified Delphi research survey to establish consensus and the appropriateness of each indicator and attribute identified in phase 1. We identified 37 indicators of critical thinking and 10 attributes of critical thinkers. The indicators were categorized into five subscales within the context of the nursing process toreflect nursing clinical practice: assessment, 16 indicators of ability to apply professional knowledge and skills to analyze and interpret patient problems; diagnosis, five indicators of ability to propose preliminary suppositions; planning, five indicators of ability to develop problem-solving strategies; implementation, five indicators of ability to implement planning; and evaluation, six indicators of ability to self-assess and reflect. The study operationalized critical thinking into a practical indicator suitable for nursing contexts in which critical thinking is required for clinical problem solving. Identified indicators and attributes can assist clinical instructors to evaluate student critical thought skills and development-related teaching strategies.
NASA Astrophysics Data System (ADS)
dos Santos, Gelson G.; Figueiredo, Giovany M.
2018-06-01
In this paper, we study the existence of nonegative solutions to a class of nonlinear boundary value problems of the Kirchhoff type. We prove existence results when the problem has discontinuous nonlinearity and critical Caffarelli-Kohn-Nirenberg growth.
Nath, S; Russell, G; Kuyken, W; Psychogiou, L; Ford, T
2016-06-01
Paternal depressive symptoms are associated with children's emotional and behavioural problems, which may be mediated by negative parenting. But there is no research on the influence of paternal depressive symptoms on children's emotion regulation and limited literature investigating fathers' parenting as a mediator in the pathway between paternal depressive symptoms and children's externalizing and internalizing problems. We aimed to investigate the mediating role of father-child conflict (at 3 years) in the association between postnatal paternal depressive symptoms (at 9 months) and children's emotional and behavioural problems (at 7 years) (aim 1). We also examined whether mediation pathways were more pronounced for boys or for girls (aim 2). Secondary data analysis was conducted on the Millennium Cohort Study, when children were 9 months, 3 years and 7 years old (n = 3520). Main study variables were measured by self-report questionnaires. Fathers completed the Rutter Scale (depressive symptoms) and the Parent-Child Relationship Questionnaire (father-child conflict), while mothers completed the Strengths and Difficulties Questionnaire and the Social Behaviour Questionnaire (child emotional and behavioural problems, emotion regulation). We used structural equation modelling to estimate direct, indirect and total effects of paternal depressive symptoms on child outcomes, mediated by father-child conflict whilst adjusting for relevant covariates (maternal depressive symptoms, child temperament, marital conflict, and socio-economic factors such as poverty indicator and fathers' education level). Multi-group and interaction analysis was then conducted to determine the differential effect by gender of the association between paternal depressive symptoms on child outcomes via father-child conflict. Father-child conflict mediated the association between paternal depressive symptoms and emotion regulation problems [standardized indirect effect (SIE) 95% confidence interval (CI) -0.03 to -0.01, p < 0.001; standardized total effect (STE) 95% CI -0.05 to -0.01, p < 0.05] (aim 1). Father-child conflict mediated a larger proportion of the effect in boys (SIE 95% CI -0.03 to -0.01, p < 0.001; STE 95% CI -0.05 to 0.00, p = 0.063) than it did in girls (SIE 95% CI -0.02 to -0.01, p < 0.001; STE 95% CI -0.04 to 0.01, p = 0.216) (aim 2). Father-child conflict may mediate the association between postnatal paternal depressive symptoms and children's emotion regulation problems. Paternal depressive symptoms and father-child conflict resolution may be potential targets in preventative interventions.
Akhtar, Shazia; Howe, Mark L; Hoepstine, Kedron
2018-06-05
Recent research has shown that false memories can have a positive consequence on human cognition in both children and young adults. The present experiment investigated whether false memories could have similar positive effects by priming solutions to insight-based problems in healthy older adults and people with Alzheimer's disease. Participants were asked to solve compound remote associate task (CRAT) problems, half of which had been preceded by the presentation of Deese/Roediger-McDermott (DRM) lists whose critical lures were also the solutions to those problems. The results showed that regardless of cognitive ability, when the critical lure was falsely recognized, CRAT problems were solved more often and reliably faster than problems that were not primed by a DRM list. When the critical lure was not falsely recognized, CRAT problem solution rates and times were no different from when there was no DRM priming. These findings are consistent with predictions from theories of associative activation and demonstrate the importance of automatic spreading activation processes in memory across the lifespan.
ERIC Educational Resources Information Center
Collins, Rachel H.
2014-01-01
In a society that is becoming more dynamic, complex, and diverse, the ability to solve ill-structured problems has become an increasingly critical skill. Emerging adults are at a critical life stage that is an ideal time to develop the skills needed to solve ill-structured problems (ISPs) as they are transitioning to adult roles and starting to…
A testable theory of problem solving courts: Avoiding past empirical and legal failures.
Wiener, Richard L; Winick, Bruce J; Georges, Leah Skovran; Castro, Anthony
2010-01-01
Recent years have seen a proliferation of problem solving courts designed to rehabilitate certain classes of offenders and thereby resolve the underlying problems that led to their court involvement in the first place. Some commentators have reacted positively to these courts, considering them an extension of the philosophy and logic of Therapeutic Jurisprudence, but others show concern that the discourse surrounding these specialty courts has not examined their process or outcomes critically enough. This paper examines that criticism from historical and social scientific perspectives. The analysis culminates in a model that describes how offenders are likely to respond to the process as they engage in problem solving court programs and the ways in which those courts might impact subsequent offender conduct. This Therapeutic Jurisprudence model of problem solving courts draws heavily on social cognitive psychology and more specifically on theories of procedural justice, motivation, and anticipated emotion to offer an explanation of how offenders respond to these programs. We offer this model as a lens through which social scientists can begin to address the concern that there is not enough critical analysis of the process and outcome of these courts. Applying this model to specialty courts constitutes an important step in critically examining the contribution of problem solving courts. Copyright © 2010 Elsevier Ltd. All rights reserved.
Greenberg, Jan; Seltzer, Marsha; Baker, Jason; Smith, Leann; Warren, Steven F; Brady, Nancy; Hong, Jinkuk
2012-07-01
We examine how the family environment is associated with aspects of the Fragile X syndrome phenotype during childhood, adolescence, and adulthood. Mothers of children (n = 48), adolescents (n = 85), and adults (n = 34) with Fragile X syndrome participated in a multisite study. For children and adults with Fragile X syndrome, the presence of warmth and positivity and the absence of criticism were associated with fewer behavior problems. Although a higher level of criticism was significantly associated with greater behavior problems, there were only trend-level associations between levels of warmth and positivity and behavior problems during the adolescent years. The provision of family psychoeducation programs, which can reduce parental criticism, would likely benefit both the individual with Fragile X syndrome and the family.
Greenberg, Jan S.; Seltzer, Marsha Mailick; Baker, Jason K.; Smith, Leann E.; Warren, Steven F.; Brady, Nancy; Hong, Jinkuk
2012-01-01
We examine how the family environment is associated with aspects of the Fragile X syndrome phenotype during childhood, adolescence, and adulthood. Mothers of children (n = 48), adolescents (n = 85), and adults (n = 34) with Fragile X syndrome participated in a multisite study. For children and adults with Fragile X syndrome, the presence of warmth and positivity and the absence of criticism were associated with fewer behavior problems. Although a higher level of criticism was significantly associated with greater behavior problems, there were only trend-level associations between levels of warmth and positivity and behavior problems during the adolescent years. The provision of family psychoeducation programs, which can reduce parental criticism, would likely benefit both the individual with Fragile X syndrome and the family. PMID:22809078
NASA Astrophysics Data System (ADS)
Cramer, S. N.; Roussin, R. W.
1981-11-01
A Monte Carlo analysis of a time-dependent neutron and secondary gamma-ray integral experiment on a thick concrete and steel shield is presented. The energy range covered in the analysis is 15-2 MeV for neutron source energies. The multigroup MORSE code was used with the VITAMIN C 171-36 neutron-gamma-ray cross-section data set. Both neutron and gamma-ray count rates and unfolded energy spectra are presented and compared, with good general agreement, with experimental results.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sanchez, R.; Mondot, J.; Stankovski, Z.
1988-11-01
APOLLO II is a new, multigroup transport code under development at the Commissariat a l'Energie Atomique. The code has a modular structure and uses sophisticated software for data structuralization, dynamic memory management, data storage, and user macrolanguage. This paper gives an overview of the main methods used in the code for (a) multidimensional collision probability calculations, (b) leakage calculations, and (c) homogenization procedures. Numerical examples are given to demonstrate the potential of the modular structure of the code and the novel multilevel flat-flux representation used in the calculation of the collision probabilities.
Calculation evaluation of multiplying properties of LWR with thorium fuel
NASA Astrophysics Data System (ADS)
Shamanin, I. V.; Grachev, V. M.; Knyshev, V. V.; Bedenko, S. V.; Novikova, N. G.
2017-01-01
The results of multiplying properties design research of the unit cell and LWR fuel assembly with the high temperature gas-cooled thorium reactor fuel pellet are presented in the work. The calculation evaluation showed the possibility of using thorium in LWR effectively. In this case the amount of fissile isotope is 2.45 times smaller in comparison with the standard loading of LWR. The research and numerical experiments were carried out using the verified accounting code of the program MCU5, modern libraries of evaluated nuclear data and multigroup approximations.
Identifying Critical Issues and Problems in Technology Education Using a Modified-Delphi Technique.
ERIC Educational Resources Information Center
Wicklein, Robert C.
1993-01-01
Critical issues for technology education (TE) identified by a 25-member Delphi panel were identification of the knowledge base, curriculum development approaches, interdisciplinary approaches, and teacher education reform. Problems identified included inadequate marketing/public relations, teacher shortage, lack of content consensus, and…
ERIC Educational Resources Information Center
Lockwood, Elise
2014-01-01
Formulas, problem types, keywords, and tricky techniques can certainly be valuable tools for successful counters. However, they can easily become substitutes for critical thinking about counting problems and for deep consideration of the set of outcomes. Formulas and techniques should serve as tools for students as they think critically about…
Difficulties for University Students with Mental Health Problems: A Critical Interpretive Synthesis
ERIC Educational Resources Information Center
Markoulakis, Roula; Kirsh, Bonnie
2013-01-01
Postsecondary institutions are witnessing an increase in the number and severity of student mental health problems, necessitating an understanding of the difficulties these students encounter in striving for higher education. The authors conducted a critical interpretive synthesis of 10 articles pertaining to difficulties experienced by students…
Unlearning, Critical Action Learning and Wicked Problems
ERIC Educational Resources Information Center
Pedler, Mike; Hsu, Shih-wei
2014-01-01
This paper explores the idea of unlearning in Critical Action Learning (CAL) as applied to the wicked problems of organisations and societies. It draws on data and ideas developed during a research project conducted for "Skills for Care" by Pedler, Abbott, Brook and Burgoyne ("Skills for Care" 2014) and from experiences on…
AEIS Policy vs. Site-Based Management: Research Agenda Implications.
ERIC Educational Resources Information Center
Nash, John B.
This paper examines the problems of centralized academic-indicator systems in light of the move toward site-based management. Problems with current practice are examined in the framework of critical inquiry. Alternatives to current accountability guidelines are presented that harmonize positivism with critical inquiry, while respecting both local…
NASA Astrophysics Data System (ADS)
Seventika, S. Y.; Sukestiyarno, Y. L.; Mariani, Scolastika
2018-03-01
The research has purpose to analyze and categorize the critical thinking ability of VHS students based on modified critical thinking indicator according to Facione-Angelo covering: interpreting the problem, analyzing alternative solution, applying the problem, evaluating the solution and concluding the results gained – attached by supportive evidence. The subject of the research is 30 eleventh graders of TKJ in Yabujah VHS, Indramayu in the odd semester 2016/2017. The collected data are critical thinking test and interviews. The result shows 15% is in good category, 30% in fair category, and 55% in low category. The students in “Good” category has accomplished critical thinking steps although imperfect, especially the indicators of evaluating and concluding attached by supportive evidence. The “Fair” categorized students only show partial steps of the indicators. The analyzing, evaluating, and concluding indicators are the most seldom to do, meanwhile the “low” categorized students show all indicators in low quality even to identify has problem to do.
An Algorithm for Critical Nodes Problem in Social Networks Based on Owen Value
Wang, Xue-Guang
2014-01-01
Discovering critical nodes in social networks has many important applications. For finding out the critical nodes and considering the widespread community structure in social networks, we obtain each node's marginal contribution by Owen value. And then we can give a method for the solution of the critical node problem. We validate the feasibility and effectiveness of our method on two synthetic datasets and six real datasets. At the same time, the result obtained by using our method to analyze the terrorist network is in line with the actual situation. PMID:25006592
Improving Critical Skills Using Wikis and CGPS in a Physics Classroom
NASA Astrophysics Data System (ADS)
Mohottala, H. E.
2016-10-01
We report the combined use of Wikispaces (wikis) and collaborative group problem solving (CGPS) sessions conducted in introductory-level calculus-based physics classes. As a part of this new teaching tool, some essay-type problems were posted on the wiki page on a weekly basis and students were encouraged to participate in problem solving without providing numerical final answers but only the steps. Each week students were further evaluated on problem solving skills, opening up more opportunity for peer interaction through CGPS. Students developed a set of skills in decision making, problem solving, communication, negotiation, critical and independent thinking, and teamwork through the combination of wikis and CGPS.
Luo, Biao; Liu, Derong; Wu, Huai-Ning
2018-06-01
Reinforcement learning has proved to be a powerful tool to solve optimal control problems over the past few years. However, the data-based constrained optimal control problem of nonaffine nonlinear discrete-time systems has rarely been studied yet. To solve this problem, an adaptive optimal control approach is developed by using the value iteration-based Q-learning (VIQL) with the critic-only structure. Most of the existing constrained control methods require the use of a certain performance index and only suit for linear or affine nonlinear systems, which is unreasonable in practice. To overcome this problem, the system transformation is first introduced with the general performance index. Then, the constrained optimal control problem is converted to an unconstrained optimal control problem. By introducing the action-state value function, i.e., Q-function, the VIQL algorithm is proposed to learn the optimal Q-function of the data-based unconstrained optimal control problem. The convergence results of the VIQL algorithm are established with an easy-to-realize initial condition . To implement the VIQL algorithm, the critic-only structure is developed, where only one neural network is required to approximate the Q-function. The converged Q-function obtained from the critic-only VIQL method is employed to design the adaptive constrained optimal controller based on the gradient descent scheme. Finally, the effectiveness of the developed adaptive control method is tested on three examples with computer simulation.
Where Is the "Critical" in Critical Thinking?
ERIC Educational Resources Information Center
Latchaw, Joan S.
Because it has been overworked, underanalyzed, and undefined, critical thinking has come to mean anything or nothing. The best work on critical thinking imagines it as an act of composing and revising. Definitions of critical thinking have undergone a historical evolution--from general problem-solving "skills" to a complex of…
Abma, Femke I; Bültmann, Ute; Amick Iii, Benjamin C; Arends, Iris; Dorland, Heleen F; Flach, Peter A; van der Klink, Jac J L; van de Ven, Hardy A; Bjørner, Jakob Bue
2017-09-09
Objective The Work Role Functioning Questionnaire v2.0 (WRFQ) is an outcome measure linking a persons' health to the ability to meet work demands in the twenty-first century. We aimed to examine the construct validity of the WRFQ in a heterogeneous set of working samples in the Netherlands with mixed clinical conditions and job types to evaluate the comparability of the scale structure. Methods Confirmatory factor and multi-group analyses were conducted in six cross-sectional working samples (total N = 2433) to evaluate and compare a five-factor model structure of the WRFQ (work scheduling demands, output demands, physical demands, mental and social demands, and flexibility demands). Model fit indices were calculated based on RMSEA ≤ 0.08 and CFI ≥ 0.95. After fitting the five-factor model, the multidimensional structure of the instrument was evaluated across samples using a second order factor model. Results The factor structure was robust across samples and a multi-group model had adequate fit (RMSEA = 0.63, CFI = 0.972). In sample specific analyses, minor modifications were necessary in three samples (final RMSEA 0.055-0.080, final CFI between 0.955 and 0.989). Applying the previous first order specifications, a second order factor model had adequate fit in all samples. Conclusion A five-factor model of the WRFQ showed consistent structural validity across samples. A second order factor model showed adequate fit, but the second order factor loadings varied across samples. Therefore subscale scores are recommended to compare across different clinical and working samples.
Brown, Susan D.; Unger Hu, Kirsten A.; Mevi, Ashley A.; Hedderson, Monique M.; Shan, Jun; Quesenberry, Charles P.; Ferrara, Assiamira
2014-01-01
The Multigroup Ethnic Identity Measure-Revised (MEIM-R), a brief instrument assessing affiliation with one’s ethnic group, is a promising advance in the ethnic identity literature. However, equivalency of its measurement properties across specific racial and ethnic groups should be confirmed before using it in diverse samples. We examined a) the psychometric properties of the MEIM-R including factor structure, measurement invariance, and internal consistency reliability, and b) levels of and differences in ethnic identity across multiple racial and ethnic groups and subgroups. Asian (n = 630), Black/African American (n = 58), Hispanic (n = 240), multiethnic (n = 160), and White (n = 375) women completed the MEIM-R as part of the “Gestational diabetes’ Effect on Moms” diabetes prevention trial in the Kaiser Permanente Northern California health care setting (N = 1,463; M age 32.5 years, SD = 4.9). Multiple-groups confirmatory factor analyses provided provisional evidence of measurement invariance, i.e., an equal, correlated two-factor structure, equal factor loadings, and equal item intercepts across racial and ethnic groups. Latent factor means for the two MEIM-R subscales, exploration and commitment, differed across groups; effect sizes ranging from small to large generally supported the notion of ethnic identity as more salient among people of color. Pending replication, good psychometric properties in this large and diverse sample of women support the future use of the MEIM-R. Preliminary evidence of measurement invariance suggests that the MEIM-R could be used to measure and compare ethnic identity across multiple racial and ethnic groups. PMID:24188656
Morales-Vives, Fabia; Dueñas, Jorge Manuel
2018-04-10
In recent years, suicide rates have increased in adolescents and the young population, so these age groups are considered as populations at risk. Considering that suicidal ideation is the first sign of possible future suicide behavior, the objective of this study is to determine the relative importance of psychological maturity, personality, depression and life satisfaction in predicting suicidal ideation in adolescents. Results show that depressive symptoms is the variable that best predicts suicidal ideation, but psychological maturity, life satisfaction and emotional stability are predictors as well (R2 = .51, p < .001). However, the Multigroup Structural Equation Models analyses carried out show that emotional stability has an indirect relationship with suicidal ideation, through its relationship with depressive symptoms, life satisfaction and identity. Two Multigroup Structural Equation Models were proposed to better understand the relationships between these variables for each sex. The results show that the fit of the model that includes the variable Self-reliance is better for boys than for girls (chi-square contributions of 8.175 for girls and 1.978 for boys) unlike the other model (chi-square contributions of 0.288 for girls and 1.650 for boys). These results suggest that the psychological maturity subscale Self-reliance play a role in suicidal ideation in males but not in females. Although there have been no previous studies on the role of psychological maturity as a predictor of suicidal phenomena, the current study suggests that it is a feature to be considered in the prediction of adolescent suicidal ideation.
Reliability generalization of the Multigroup Ethnic Identity Measure-Revised (MEIM-R).
Herrington, Hayley M; Smith, Timothy B; Feinauer, Erika; Griner, Derek
2016-10-01
[Correction Notice: An Erratum for this article was reported in Vol 63(5) of Journal of Counseling Psychology (see record 2016-33161-001). The name of author Erika Feinauer was misspelled as Erika Feinhauer. All versions of this article have been corrected.] Individuals' strength of ethnic identity has been linked with multiple positive indicators, including academic achievement and overall psychological well-being. The measure researchers use most often to assess ethnic identity, the Multigroup Ethnic Identity Measure (MEIM), underwent substantial revision in 2007. To inform scholars investigating ethnic identity, we performed a reliability generalization analysis on data from the revised version (MEIM-R) and compared it with data from the original MEIM. Random-effects weighted models evaluated internal consistency coefficients (Cronbach's alpha). Reliability coefficients for the MEIM-R averaged α = .88 across 37 samples, a statistically significant increase over the average of α = .84 for the MEIM across 75 studies. Reliability coefficients for the MEIM-R did not differ across study and participant characteristics such as sample gender and ethnic composition. However, consistently lower reliability coefficients averaging α = .81 were found among participants with low levels of education, suggesting that greater attention to data reliability is warranted when evaluating the ethnic identity of individuals such as middle-school students. Future research will be needed to ascertain whether data with other measures of aspects of personal identity (e.g., racial identity, gender identity) also differ as a function of participant level of education and associated cognitive or maturation processes. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Limbers, Christine A; Newman, Daniel A; Varni, James W
2008-01-01
The utilization of health-related quality of life (HRQOL) measurement in an effort to improve pediatric health and well-being and determine the value of health care services has grown dramatically over the past decade. The paradigm shift toward patient-reported outcomes (PROs) in clinical trials has provided the opportunity to emphasize the value and essential need for pediatric patient self-report. In order for HRQOL/PRO comparisons to be meaningful for subgroup analyses, it is essential to demonstrate factorial invariance. This study examined age subgroup factorial invariance of child self-report for ages 5 to 16 years on more than 8,500 children utilizing the PedsQL 4.0 Generic Core Scales. Multigroup Confirmatory Factor Analysis (MGCFA) was performed specifying a five-factor model. Two multigroup structural equation models, one with constrained parameters and the other with unconstrained parameters, were proposed to compare the factor loadings across the age subgroups. Metric invariance (i.e., equal factor loadings) across the age subgroups was demonstrated based on stability of the Comparative Fit Index between the two models, and several additional indices of practical fit including the Root Mean Squared Error of Approximation, the Non-Normed Fit Index, and the Parsimony Normed Fit Index. The findings support an equivalent five-factor structure across the age subgroups. Based on these data, it can be concluded that children across the age subgroups in this study interpreted items on the PedsQL 4.0 Generic Core Scales in a similar manner regardless of their age.
Gadermann, Anne M; Sawatzky, Richard; Palepu, Anita; Hubley, Anita M; Zumbo, Bruno D; Aubry, Tim; Farrell, Susan; Hwang, Stephen W
2017-06-01
The purpose of this study was to examine whether homeless or vulnerably housed individuals experienced response shift over a 12-month time period in their self-reported physical and mental health status. Data were obtained from the Health and Housing in Transition study, a longitudinal multi-site cohort study in Canada (N = 1190 at baseline). Multi-group confirmatory factor analysis (MG-CFA) and methods for response shift detection at the item level, based on the approach by Oort, were used to test for reconceptualization, reprioritization, and recalibration response shift on the SF-12 in four groups of individuals who were homeless (n = 170), housed (n = 437), or who reported a change in their housing status [from homeless to housed (n = 285) or housed to homeless (n = 73)] over a 12-month time period. Mean and variance adjusted weighted-least squares estimation was used to accommodate the ordinal and binary distributions of the SF-12 items. Using MG-CFA, a strict invariance model showed that the measurement model was equivalent for the four groups at baseline. Although we found small but statistically significant response shift for several measurement model parameters, the impact on the predicted average mental and physical health scores within each of the groups was small. Response shift does not appear to be a significant concern when using the SF-12 to obtain change scores over a 12-month period in this population.
SIS and SIR epidemic models under virtual dispersal
Bichara, Derdei; Kang, Yun; Castillo-Chavez, Carlos; Horan, Richard; Perrings, Charles
2015-01-01
We develop a multi-group epidemic framework via virtual dispersal where the risk of infection is a function of the residence time and local environmental risk. This novel approach eliminates the need to define and measure contact rates that are used in the traditional multi-group epidemic models with heterogeneous mixing. We apply this approach to a general n-patch SIS model whose basic reproduction number R0 is computed as a function of a patch residence-times matrix ℙ. Our analysis implies that the resulting n-patch SIS model has robust dynamics when patches are strongly connected: there is a unique globally stable endemic equilibrium when R0 > 1 while the disease free equilibrium is globally stable when R0 ≤ 1. Our further analysis indicates that the dispersal behavior described by the residence-times matrix ℙ has profound effects on the disease dynamics at the single patch level with consequences that proper dispersal behavior along with the local environmental risk can either promote or eliminate the endemic in particular patches. Our work highlights the impact of residence times matrix if the patches are not strongly connected. Our framework can be generalized in other endemic and disease outbreak models. As an illustration, we apply our framework to a two-patch SIR single outbreak epidemic model where the process of disease invasion is connected to the final epidemic size relationship. We also explore the impact of disease prevalence driven decision using a phenomenological modeling approach in order to contrast the role of constant versus state dependent ℙ on disease dynamics. PMID:26489419
Gale, Catharine R; Allerhand, Michael; Sayer, Avan Aihie; Cooper, Cyrus; Dennison, Elaine M; Starr, John M; Ben-Shlomo, Yoav; Gallacher, John E; Kuh, Diana; Deary, Ian J
2010-06-01
The Hospital Anxiety and Depression Scale (HADS) is widely used but evaluation of its psychometric properties has produced equivocal results. Little is known about its structure in non-clinical samples of older people. We used data from four cohorts in the HALCyon collaborative research program into healthy aging: the Caerphilly Prospective Study, the Hertfordshire Ageing Study, the Hertfordshire Cohort Study, and the Lothian Birth Cohort 1921. We used exploratory factor analysis and confirmatory factor analysis with multi-group comparisons to establish the structure of the HADS and test for factorial invariance between samples. Exploratory factor analysis showed a bi-dimensional structure (anxiety and depression) of the scale in men and women in each cohort. We tested a hypothesized three-factor model but high correlations between two of the factors made a two-factor model more psychologically plausible. Multi-group confirmatory factor analysis revealed that the sizes of the respective item loadings on the two factors were effectively identical in men and women from the same cohort. There was more variation between cohorts, particularly those from different parts of the U.K. and in whom the HADS was administered differently. Differences in social-class distribution accounted for part of this variation. Scoring the HADS as two subscales of anxiety and depression is appropriate in non-clinical populations of older men and women. However, there were differences between cohorts in the way that individual items were linked with the constructs of anxiety and depression, perhaps due to differences in sociocultural factors and/or in the administration of the scale.
Associations among everyday stress, critical life events, and sexual problems.
Bodenmann, Guy; Ledermann, Thomas; Blattner, Denise; Galluzzo, Claudia
2006-07-01
This study addresses the question of how stress is linked to sexual problems among women and men in close relationships. Psychological symptoms, relationship quality, internal daily stress (i.e., originating within the couple such as conflicts, worry for the partner), external daily stress (i.e., stress arising outside the couple such as job stress, stressful relatives, and so forth), and critical life events were examined with regard to their association with different sexual problems. The results support the hypotheses that (1) there is an incremental effect of stress on sexual problems after controlling for psychological symptoms and relationship quality, and that (2) it is primarily internal daily stress and in some cases critical life events rather than external daily stress that are related to sexual problems, particularly hypoactive sexual desire in women and men, sexual aversion in women, vaginismus in women, and premature ejaculation in men. Our findings indicate that the treatment of these sexual problems should address relationship issues and include a focus on helping individuals improve their stress management skills within their couple relationship.
Scoping analysis of the Advanced Test Reactor using SN2ND
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wolters, E.; Smith, M.; SC)
2012-07-26
A detailed set of calculations was carried out for the Advanced Test Reactor (ATR) using the SN2ND solver of the UNIC code which is part of the SHARP multi-physics code being developed under the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program in DOE-NE. The primary motivation of this work is to assess whether high fidelity deterministic transport codes can tackle coupled dynamics simulations of the ATR. The successful use of such codes in a coupled dynamics simulation can impact what experiments are performed and what power levels are permitted during those experiments at the ATR. The advantages of themore » SN2ND solver over comparable neutronics tools are its superior parallel performance and demonstrated accuracy on large scale homogeneous and heterogeneous reactor geometries. However, it should be noted that virtually no effort from this project was spent constructing a proper cross section generation methodology for the ATR usable in the SN2ND solver. While attempts were made to use cross section data derived from SCALE, the minimal number of compositional cross section sets were generated to be consistent with the reference Monte Carlo input specification. The accuracy of any deterministic transport solver is impacted by such an approach and clearly it causes substantial errors in this work. The reasoning behind this decision is justified given the overall funding dedicated to the task (two months) and the real focus of the work: can modern deterministic tools actually treat complex facilities like the ATR with heterogeneous geometry modeling. SN2ND has been demonstrated to solve problems with upwards of one trillion degrees of freedom which translates to tens of millions of finite elements, hundreds of angles, and hundreds of energy groups, resulting in a very high-fidelity model of the system unachievable by most deterministic transport codes today. A space-angle convergence study was conducted to determine the meshing and angular cubature requirements for the ATR, and also to demonstrate the feasibility of performing this analysis with a deterministic transport code capable of modeling heterogeneous geometries. The work performed indicates that a minimum of 260,000 linear finite elements combined with a L3T11 cubature (96 angles on the sphere) is required for both eigenvalue and flux convergence of the ATR. A critical finding was that the fuel meat and water channels must each be meshed with at least 3 'radial zones' for accurate flux convergence. A small number of 3D calculations were also performed to show axial mesh and eigenvalue convergence for a full core problem. Finally, a brief analysis was performed with different cross sections sets generated from DRAGON and SCALE, and the findings show that more effort will be required to improve the multigroup cross section generation process. The total number of degrees of freedom for a converged 27 group, 2D ATR problem is {approx}340 million. This number increases to {approx}25 billion for a 3D ATR problem. This scoping study shows that both 2D and 3D calculations are well within the capabilities of the current SN2ND solver, given the availability of a large-scale computing center such as BlueGene/P. However, dynamics calculations are not realistic without the implementation of improvements in the solver.« less
Do Colleges Cultivate Critical Thinking, Problem Solving, Writing and Interpersonal Skills?
ERIC Educational Resources Information Center
Saavedra, Anna Rosefsky; Saavedra, Juan Esteban
2011-01-01
We investigate how much value college enrollment adds to students' critical thinking, problem-solving and communication skills, and the role college inputs play in developing these competencies, using data from a 2009 collegiate assessment pilot study in Colombia. Relative to observationally similar first year students, students in their final…
Problems in the Research Problem: Critical Feedback and Resistance in Academic Supervision
ERIC Educational Resources Information Center
Vehvilainen, Sanna
2009-01-01
The paper focuses on a routine activity of academic supervision: Giving and receiving feedback based on the student's master's thesis manuscript. Two case analyses are presented on fundamentally critical feedback. Such feedback constitutes a recommendation to the student to seriously rethink the thesis, but there are various interactional…
Critical Analysis of the Problems of Education in Pakistan: Possible Solutions
ERIC Educational Resources Information Center
Ahmad, Iqbal; ur Rehman, Kahil; Ali, Asghar; Khan, Itbar; Khan, Fazal Akber
2014-01-01
Education lays the foundation for political, social and economic development of any country. A viable education system enables the nation to achieve its national goals. Pakistan as a developing country has faced critical problems of education since its inception and therefore, the system of education has failed to deliver according to the…
ERIC Educational Resources Information Center
Junsay, Merle L.
2016-01-01
This is a quasi-experimental study that explored the effects of reflective learning on prospective teachers' conceptual understanding, critical thinking, problem solving, and mathematical communication skills and the relationship of these variables. It involved 60 prospective teachers from two basic mathematics classes of an institution of higher…
CRITICAL PROBLEMS AND NEEDS OF CALIFORNIA JUNIOR COLLEGES.
ERIC Educational Resources Information Center
PETERSON, BASIL H.; AND OTHERS
THROUGH A PROCEDURE INVOLVING RESPONSES FROM 85 PERCENT OF THE STATE JUNIOR COLLEGES AND WEIGHTED RANK ORDERING OF ITEMS BY MEMBERS OF THE CALIFORNIA JUNIOR COLLEGE ASSOCIATION COMMITTEE'S ADVISORY AND STEERING SUBCOMMITTEES, 26 OF THE MOST CRITICAL NEEDS AND PROBLEMS ARE IDENTIFIED AND RANKED. THE FIRST FIVE ITEMS ARE CONCERN FOR EFFECTIVENESS…
Teaching to Teach (with) Game Design: Game Design and Learning Workshops for Preservice Teachers
ERIC Educational Resources Information Center
Akcaoglu, Mete; Kale, Ugur
2016-01-01
Engagement in game design tasks can help preservice teachers develop pedagogical and technical skills for teaching and promoting critical thinking and problem-solving skills. Through the design process, preservice teachers not only exercise critical-thinking and problem-solving skills, but also learn about an instructional method to support their…
Development of Critical Thinking Self-Assessment System Using Wearable Device
ERIC Educational Resources Information Center
Gotoh, Yasushi
2015-01-01
In this research the author defines critical thinking as skills and dispositions which enable one to solve problems logically and to attempt to reflect autonomously by means of meta-cognitive activities on one's own problem-solving processes. The author focuses on providing meta-cognitive knowledge to help with self-assessment. To develop…
ERIC Educational Resources Information Center
Ampuero, David; Miranda, Christian E.; Delgado, Luisa E.; Goyen, Samantha; Weaver, Sean
2015-01-01
The present study explores the outcomes of teaching empathy and critical thinking to solve environmental problems. This investigation was done throughout the duration of an environmental education course within a primary school located in central Chile. A community-based research methodology was used to understand the formation of empathy and…
ERIC Educational Resources Information Center
General Accounting Office, Washington, DC. General Government Div.
The General Accounting Office examined the Office of Personnel Management's (OPM's) leadership role in addressing critical human resource problems and preparing the government to meet future challenges. Federal managers, OPM employees, and federal personnel officials were surveyed to study federal government problems in hiring, managing, and…
Creative and Critical Thinking Skills in Problem-Based Learning Environments
ERIC Educational Resources Information Center
Birgili, Bengi
2015-01-01
Creative and critical thinking skills are the abilities, which can sometimes be used interchangeably in definition. In fact, they have different constructs because they differentiate in outcome of human behaviours. Also one of today's requirements is that individuals should approach everyday problems by using both competences. So, one of the…
A Methodological Critique of "Interventions for Boys with Conduct Problems"
ERIC Educational Resources Information Center
Kent, Ronald; And Others
1976-01-01
Kent criticizes Patterson's study on treating the behavior problems of boys, on several methodological bases concluding that more rigorous research is required in this field. Patterson answers Kent's criticisms arguing that they are not based on sound grounds. Patterson offers further evidence to support the efficacy of his treatment procedures.…
Narusyte, Jurgita; Neiderhiser, Jenae M; Andershed, Anna-Karin; D'Onofrio, Brian M; Reiss, David; Spotts, Erica; Ganiban, Jody; Lichtenstein, Paul
2011-05-01
Genetic factors are important for the association between parental negativity and child problem behavior, but it is not clear whether this is due to passive or evocative genotype-environment correlation (rGE). In this study, we applied the extended children-of-twins model to directly examine the presence of passive and evocative rGE as well as direct environmental effects in the association between parental criticism and adolescent externalizing problem behavior. The cross-sectional data come from the Twin and Offspring Study in Sweden (N = 909 pairs of adult twins) and from the Twin Study of Child and Adolescent Development (N = 915 pairs of twin children). The results revealed that maternal criticism was primarily due to evocative rGE emanating from their adolescent's externalizing behavior. On the other hand, fathers' critical remarks tended to affect adolescent problem behavior in a direct environmental way. This suggests that previously reported differences in caretaking between mothers and fathers also are reflected in differences in why parenting is associated with externalizing behavior in offspring.
Narusyte, Jurgita; Neiderhiser, Jenae M.; Andershed, Anna-Karin; D’Onofrio, Brian M.; Reiss, David; Spotts, Erica; Ganiban, Jody; Lichtenstein, Paul
2011-01-01
Genetic factors are important for the association between parental negativity and child problem behavior, but it is not clear whether this is dueto passive or evocative genotype-environment correlation (rGE). In this study we applied the extended children-of-twins model to directly examine the presence of passive and evocative rGE as well as direct environmental effects in the association between parental criticism and adolescent externalizing problem behavior. The cross-sectional data come from the Twin and Offspring Study in Sweden (TOSS) (N=909 pairs of adult twins) and from the Twin study of CHild and Adolescent Development (TCHAD) (N=915 pairs of twin children). The results revealed that maternal criticism was primarily due to evocative rGE emanating from their adolescent’s externalizing behavior. On the other hand, fathers’ critical remarks tended to affect adolescent problem behavior in a direct environmental way. This suggests that previously reported differences in caretaking between mothers and fathers also are reflected in differences in why parenting is associated with externalizing behavior in offspring. PMID:21280930
Critical care helps people with life-threatening injuries and illnesses. It might treat problems such as complications from surgery, ... attention by a team of specially-trained health care providers. Critical care usually takes place in an ...
Malaysia's social policies on mental health: a critical theory.
Mubarak, A Rahamuthulla
2003-01-01
This article aims to review the social policies on mental health and mental illness in Malaysia. Using critical theory, major policy issues pertaining to mental health and mental illness such as mental health legislation, prevalence rates and quality of services available to the people with mental health problems are discussed in detail. Implications of these issues on persons with mental health problems are critically evaluated. The paper highlights that the other countries in ASEAN region also require similar review by policy literature.
Pope, Megan A; Malla, Ashok K; Iyer, Srividya N
2018-05-01
Individuals with mental health problems have many support needs that are often inadequately met; however, perceptions of who should be responsible for meeting these needs have been largely unexplored. Varying perceptions may influence whether, how, and to what extent relevant stakeholders support individuals with mental health problems. To critically evaluate the literature to determine who different stakeholders believe should be responsible for supporting individuals with mental health problems, what factors shape these perceptions, and how they relate to one another. A critical literature review was undertaken. Following an extensive literature search, the conceptual contributions of relevant works were critically evaluated. A concept map was created to build a conceptual framework of the topic. Views of individual versus societal responsibility for need provision and health; the morality of caring; and attributions of responsibility for mental illness offered valuable understandings of the review questions. Creating a concept map revealed that various interrelated factors may influence perceptions of responsibility. Varying perceptions of who should be responsible for supporting individuals with mental health problems may contribute to unmet support needs among this group. Our critical review helps build a much-needed conceptual framework of factors influencing perceptions of responsibility. Such a framework is essential as these views iteratively shape and reflect the complex divisions of mental healthcare roles and responsibilities. Understanding these perceptions can help define relevant stakeholders' roles more clearly, which can improve mental health services and strengthen stakeholder accountability.
Yuan, Haobin; Williams, Beverly A; Fan, Lin
2008-08-01
Rapidly changing developments and expanding roles in healthcare environment requires professional nurses to develop critical thinking. Nursing education strives to facilitate students' critical thinking through the appropriate instructional approaches. Problem-based learning (PBL) is a student-centered approach to learning which enables the students to work cooperatively in small groups for seeking solutions to situations/problems. The systematic review was conducted to provide the available evidence on developing nursing students' critical thinking through PBL. The computerized searches from 1990-2006 in CINAHL, Proquest, Cochrane library, Pubmed etc were performed. All studies which addressed the differences in critical thinking among nursing students in PBL were considered. Two independent reviewers assessed the eligibility of each study, its level of evidence and the methodological quality. As a result, only ten studies were retrieved, they were: one RCT with a Jadad quality score of 3, one nonrandomized control study, two quasi-experimental studies with non-controlled pretest-posttest design, and six descriptive studies. The available evidence in this review did not provide supportive evidence on developing nursing students' critical thinking through PBL. Clearly, there is a need for additional research with larger sample size and high quality to clarify the effects of PBL on critical thinking development within nursing educational context.
Deutsch, Arielle R; Crockett, Lisa J; Wolff, Jennifer M; Russell, Stephen T
2012-08-01
Effects of ethnicity and neighborhood quality often are confounded in research on adolescent delinquent behavior. This study examined the pathways to delinquency among 2,277 African American and 5,973 European American youth residing in high-risk and low-risk neighborhoods. Using data from a national study of youth, a meditational model was tested in which parenting practices (parental control and maternal support) were hypothesized to influence adolescents' participation in delinquent behavior through their affiliation with deviant peers. The relationships of family and neighborhood risk to parenting practices and deviant peer affiliation were also examined. Results of multi-group structural equation models provided support for the core meditational model in both ethnic groups, as well as evidence of a direct effect of maternal support on delinquency. When a similar model was tested within each ethnic group to compare youths residing in high-risk and low-risk neighborhoods, few neighborhood differences were found. The results indicate that, for both African American and European American youth, low parental control influences delinquency indirectly through its effect on deviant peer affiliation, whereas maternal support has both direct and indirect effects. However, the contextual factors influencing parenting practices and deviant peer affiliation appear to vary somewhat across ethnic groups. Overall the present study highlights the need to look at the joint influence of neighborhood context and ethnicity on adolescent problem behavior.
Monte Carlo Modeling of Non-Local Electron Conduction in High Energy Density Plasmas
NASA Astrophysics Data System (ADS)
Chenhall, Jeffrey John
The implicit SNB (iSNB) non-local multigroup thermal electron conduction method of Schurtz et. al. [Phys. Plasmas 7, 4238 (2000)] and Cao et. al. [Phys. Plasmas 22, 082308 (2015)] is adapted into an electron thermal transport Monte Carlo (ETTMC) transport method to better model higher order angular and long mean free path non-local effects. The ETTMC model is used to simulate the electron thermal transport within inertial confinement fusion (ICF) type problems. The new model aims to improve upon the currently used iSNB, in particular by using finite particle ranges in comparison to the exponential solution of a diffusion method and by improved higher order angular modeling. The new method has been implemented in the 1D LILAC and 2D DRACO multiphysics production codes developed by the University of Rochester Laboratory for Laser Energetics. The ETTMC model is compared to iSNB for several direct drive ICF type simulations: Omega shot 60303 a shock timing experiment, Omega shot 59529 a shock timing experiment, Omega shot 68951 a cryogenic target implosion and a NIF polar direct drive phase plate design. Overall, the ETTMC method performs at least as well as the iSNB method and predicts lower preheating ahead of the shock fronts. This research was supported by University of Rochester Laboratory for Laser Energetics, Sandia National Laboratories and the University of Wisconsin-Madison Foundation.
Ozturk, Candan; Muslu, Gonca Karayagiz; Dicle, Aklime
2008-07-01
Determining the critical thinking (CT) levels of students in undergraduate nursing schools is important in terms of establishing the methods of education that should be used. Although there is some evidence that active learning approaches like problem-based learning are effective in developing CT, the findings are inconclusive. This descriptive analytic study compared levels of critical thinking among senior nursing students (N=147) in two educational programs, one of which used a problem-based learning (PBL) model while the other used a traditional model. The California critical thinking disposition inventory (CCTDI) was used as a data collection tool. Comparisons between the groups were made using t-test analysis. There was a significant difference (p<0.05) between the critical thinking disposition scores of the seniors in the PBL school and those in the school implementing the traditional model. Analysis of sub-scale scores showed significant differences in truth-seeking and open-mindedness. These findings add to the evidence that the active and self-directed nature of PBL encourages students' ability to think critically, be tolerant of the ideas of others and evaluate conflicting information before reaching a conclusion.
Combined Use of Integral Experiments and Covariance Data
NASA Astrophysics Data System (ADS)
Palmiotti, G.; Salvatores, M.; Aliberti, G.; Herman, M.; Hoblit, S. D.; McKnight, R. D.; Obložinský, P.; Talou, P.; Hale, G. M.; Hiruta, H.; Kawano, T.; Mattoon, C. M.; Nobre, G. P. A.; Palumbo, A.; Pigni, M.; Rising, M. E.; Yang, W.-S.; Kahler, A. C.
2014-04-01
In the frame of a US-DOE sponsored project, ANL, BNL, INL and LANL have performed a joint multidisciplinary research activity in order to explore the combined use of integral experiments and covariance data with the objective to both give quantitative indications on possible improvements of the ENDF evaluated data files and to reduce at the same time crucial reactor design parameter uncertainties. Methods that have been developed in the last four decades for the purposes indicated above have been improved by some new developments that benefited also by continuous exchanges with international groups working in similar areas. The major new developments that allowed significant progress are to be found in several specific domains: a) new science-based covariance data; b) integral experiment covariance data assessment and improved experiment analysis, e.g., of sample irradiation experiments; c) sensitivity analysis, where several improvements were necessary despite the generally good understanding of these techniques, e.g., to account for fission spectrum sensitivity; d) a critical approach to the analysis of statistical adjustments performance, both a priori and a posteriori; e) generalization of the assimilation method, now applied for the first time not only to multigroup cross sections data but also to nuclear model parameters (the "consistent" method). This article describes the major results obtained in each of these areas; a large scale nuclear data adjustment, based on the use of approximately one hundred high-accuracy integral experiments, will be reported along with a significant example of the application of the new "consistent" method of data assimilation.
How Critical Is Critical Thinking?
ERIC Educational Resources Information Center
Shaw, Ryan D.
2014-01-01
Recent educational discourse is full of references to the value of critical thinking as a 21st-century skill. In music education, critical thinking has been discussed in relation to problem solving and music listening, and some researchers suggest that training in critical thinking can improve students' responses to music. But what exactly is…
Contribution of Emotional Intelligence towards Graduate Students' Critical Thinking Disposition
ERIC Educational Resources Information Center
Kang, Fong-Luan
2015-01-01
Good critical thinkers possess a core set of cognitive thinking skills, and a disposition towards critical thinking. They are able to think critically to solve complex, real-world problems effectively. Although personal emotion is important in critical thinking, it is often a neglected issue. The emotional intelligence in this study concerns our…
Fault tolerance of artificial neural networks with applications in critical systems
NASA Technical Reports Server (NTRS)
Protzel, Peter W.; Palumbo, Daniel L.; Arras, Michael K.
1992-01-01
This paper investigates the fault tolerance characteristics of time continuous recurrent artificial neural networks (ANN) that can be used to solve optimization problems. The principle of operations and performance of these networks are first illustrated by using well-known model problems like the traveling salesman problem and the assignment problem. The ANNs are then subjected to 13 simultaneous 'stuck at 1' or 'stuck at 0' faults for network sizes of up to 900 'neurons'. The effects of these faults is demonstrated and the cause for the observed fault tolerance is discussed. An application is presented in which a network performs a critical task for a real-time distributed processing system by generating new task allocations during the reconfiguration of the system. The performance degradation of the ANN under the presence of faults is investigated by large-scale simulations, and the potential benefits of delegating a critical task to a fault tolerant network are discussed.
Robustness of mission plans for unmanned aircraft
NASA Astrophysics Data System (ADS)
Niendorf, Moritz
This thesis studies the robustness of optimal mission plans for unmanned aircraft. Mission planning typically involves tactical planning and path planning. Tactical planning refers to task scheduling and in multi aircraft scenarios also includes establishing a communication topology. Path planning refers to computing a feasible and collision-free trajectory. For a prototypical mission planning problem, the traveling salesman problem on a weighted graph, the robustness of an optimal tour is analyzed with respect to changes to the edge costs. Specifically, the stability region of an optimal tour is obtained, i.e., the set of all edge cost perturbations for which that tour is optimal. The exact stability region of solutions to variants of the traveling salesman problems is obtained from a linear programming relaxation of an auxiliary problem. Edge cost tolerances and edge criticalities are derived from the stability region. For Euclidean traveling salesman problems, robustness with respect to perturbations to vertex locations is considered and safe radii and vertex criticalities are introduced. For weighted-sum multi-objective problems, stability regions with respect to changes in the objectives, weights, and simultaneous changes are given. Most critical weight perturbations are derived. Computing exact stability regions is intractable for large instances. Therefore, tractable approximations are desirable. The stability region of solutions to relaxations of the traveling salesman problem give under approximations and sets of tours give over approximations. The application of these results to the two-neighborhood and the minimum 1-tree relaxation are discussed. Bounds on edge cost tolerances and approximate criticalities are obtainable likewise. A minimum spanning tree is an optimal communication topology for minimizing the cumulative transmission power in multi aircraft missions. The stability region of a minimum spanning tree is given and tolerances, stability balls, and criticalities are derived. This analysis is extended to Euclidean minimum spanning trees. This thesis aims at enabling increased mission performance by providing means of assessing the robustness and optimality of a mission and methods for identifying critical elements. Examples of the application to mission planning in contested environments, cargo aircraft mission planning, multi-objective mission planning, and planning optimal communication topologies for teams of unmanned aircraft are given.
ERIC Educational Resources Information Center
Kazdin, Alan E.
2009-01-01
Climate change and degradation of the environment are global problems associated with many other challenges (e.g., population increases, reduction of glaciers, and loss of critical habitats). Psychological science can play a critical role in addressing these problems by fostering a sustainable environment. Multiple strategies for fostering a…
ERIC Educational Resources Information Center
Widyatiningtyas, Reviandari; Kusumah, Yaya S.; Sumarmo, Utari; Sabandar, Jozua
2015-01-01
The study reported the findings of an only post-test control group research design and aims to analyze the influence of problem-based learning approach, school level, and students' prior mathematical ability to student's mathematics critical thinking ability. The research subjects were 140 grade ten senior high school students coming from…
ERIC Educational Resources Information Center
Zetriuslita; Wahyudin; Jarnawi
2017-01-01
This research aims to describe and analyze result of applying Problem-Based Learning and Cognitive Conflict Strategy (PBLCCS) in increasing students' Mathematical Critical Thinking (MCT) ability and Mathematical Curiosity Attitude (MCA). Adopting a quasi-experimental method with pretest-posttest control group design and using mixed method with…
Collaborative Problem Solving Methods towards Critical Thinking
ERIC Educational Resources Information Center
Yin, Khoo Yin; Abdullah, Abdul Ghani Kanesan; Alazidiyeen, Naser Jamil
2011-01-01
This research attempts to examine the collaborative problem solving methods towards critical thinking based on economy (AE) and non economy (TE) in the SPM level among students in the lower sixth form. The quasi experiment method that uses the modal of 3X2 factorial is applied. 294 lower sixth form students from ten schools are distributed…
ERIC Educational Resources Information Center
Tsoubaris, Dimitris; Georgopoulos, Aleksandros
2013-01-01
The objective of this qualitative research work is to detect the needs, aspirations and feelings of pupils experiencing local environmental problems and elaborate them through the prism of a socially critical educational approach. Semi-structured focus group interviews are used as a research method applied to four primary schools located near…
ERIC Educational Resources Information Center
Marigliano, Michelle L.; Russo, Michele J.
2011-01-01
Creative movement is an ideal way to help young children develop critical-thinking and problem-solving skills. Most young children are, by nature, extremely physical. They delight in exploring the world with their bodies and expressing their ideas and feelings through movement. During creative movement experiences, children learn to think before…
ERIC Educational Resources Information Center
Tickles, Virginia C.; Li, Yadong; Walters, Wilbur L.
2013-01-01
Much criticism exists concerning a lack of focus on real-world problem-solving in the science, technology, engineering and mathematics (STEM) infrastructures. Many of these critics say that current educational infrastructures are incapable in preparing future scientists and engineers to solve the complex and multidisciplinary problems this society…
ERIC Educational Resources Information Center
Turner, Rita; Donnelly, Ryan
2013-01-01
This article outlines the features and application of a set of model curriculum materials that utilize eco-democratic principles and humanities-based content to cultivate critical analysis of the cultural foundations of socio-environmental problems. We first describe the goals and components of the materials, then discuss results of their use in…
ERIC Educational Resources Information Center
Snodgrass, Suzanne
2011-01-01
Health professionals use critical thinking, a key problem solving skill, for clinical reasoning which is defined as the use of knowledge and reflective inquiry to diagnose a clinical problem. Teaching these skills in traditional settings with growing class sizes is challenging, and students increasingly expect learning that is flexible and…
Developing Deep Group Reflection within a Critical Reflection Action Learning Set
ERIC Educational Resources Information Center
Shepherd, Gary
2016-01-01
This account of practice describes how a manufacturing company in the North of England transformed their approach to problem-solving and action through the use of a Critical Reflection Action Learning (CRAL) methodology. The company, who had been in business for over 25 years, experienced problems due to a diminishing customer base and substantial…
Psychology in Education as Developmental Healthcare: A Proposal for Fundamental Change and Survival.
ERIC Educational Resources Information Center
Bagnato, Stephen J.
The survival of psychologists and psychological services in public education is a pressing concern of critical importance to children, families, and school systems. Psychologists advocate that the critical first step for clients to change behavior and personality is to define the problem and to accept its validity. The main problem facing…
ERIC Educational Resources Information Center
Anggrianto, Desi; Churiyah, Madziatul; Arief, Mohammad
2016-01-01
This research was conducted in order to know the effect of Logan Avenue Problem Solving (LAPS)-Heuristic learning model towards critical thinking skills of students of class X Office Administration (APK) in SMK Negeri 1 Ngawi, East Java, Indonesia on material curve and equilibrium of demand and supply, subject Introduction to Economics and…
ERIC Educational Resources Information Center
Ceaser, Donovon
2012-01-01
Despite wide agreement on the goals of environmental education (EE), the promotion of action is still considered contentious. Critical environmental education (critical EE) teaches students to combine critical reflection with the ability to engage in local action to address social/environmental problems. This article examines a critical urban…
Teaching and evaluating critical thinking in respiratory care.
Mishoe, Shelley C; Hernlen, Kitty
2005-09-01
The capacity to perform critical thinking in respiratory care may be enhanced through awareness and education to improve skills, abilities, and opportunities. The essential skills for critical thinking in respiratory care include prioritizing, anticipating, troubleshooting, communicating, negotiating, decision making, and reflecting. In addition to these skills, critical thinkers exhibit certain characteristics such as critical evaluation, judgment,insight, motivation, and lifelong learning. The teaching of critical thinking may be accomplished though problem-based learning using an evidenced-based approach to solve clinical problems similar to those encountered in professional practice. Other traditional strategies such as discussion, debate, case study, and case presentations can be used. Web-based curriculum and technologic advances have created opportunities such as bulletin boards, real-time chats, and interactive media tools that can incorporate critical thinking. Many concerns and controversies surround the assessment of critical thinking, and individuals who administer critical thinking tests must be aware of the strengths and limitations of these assessment tools, as well as their relevance to the workplace. The foundational works reported in this article summarize the current status of assessment of critical thinking and can stimulate further investigation and application of the skills, characteristics, educational strategies, and measurement of critical thinking in respiratory care.
The effects of critical thinking instruction on training complex decision making.
Helsdingen, Anne S; van den Bosch, Karel; van Gog, Tamara; van Merriënboer, Jeroen J G
2010-08-01
Two field studies assessed the effects of critical thinking instruction on training and transfer of a complex decision-making skill. Critical thinking instruction is based on studies of how experienced decision makers approach complex problems. Participants conducted scenario-based exercises in both simplified (Study I) and high-fidelity (Study 2) training environments. In both studies, half of the participants received instruction in critical thinking. The other half conducted the same exercises but without critical thinking instruction. After the training, test scenarios were administered to both groups. The first study showed that critical thinking instruction enhanced decision outcomes during both training and the test. In the second study, critical thinking instruction benefited both decision outcomes and processes, specifically on the transfer to untrained problems. The results suggest that critical thinking instruction improves decision strategy and enhances understanding of the general principles of the domain. The results of this study warrant the implementation of critical thinking instruction in training programs for professional decision makers that have to operate in complex and highly interactive, dynamic environments.
Jennings, Bonnie Mowinski; Lamb, Gerri
2007-09-01
Health care system issues, in general, and access to care, in particular, are not problems typically studied by critical care nurses. Rather, initial and continuing education focuses on clinical aspects of care. This focus is necessary to assure that critical care nurses have the expertise to care for patients who need astute surveillance for complicated physical problems and their emotional sequelae, as well as in-depth knowledge and skills related to care coordination for patient stabilization and transfer. However, evidence is growing that patients benefit when critical care nurses expand their knowledge about access to care. This article provides insights regarding access to health care and how it relates to many of the admission and readmission patterns that critical care nurses observe.
When a Problem Is More than a Teacher's Question
ERIC Educational Resources Information Center
Olson, Jo Clay; Knott, Libby
2013-01-01
Not only are the problems teachers pose throughout their teaching of great importance but also the ways in which they use those problems make this a critical component of teaching. A problem-posing episode includes the problem setup, the statement of the problem, and the follow-up questions. Analysis of problem-posing episodes of precalculus…
A Capabilities Based Assessment of the United States Air Force Critical Care Air Transport Team
2013-09-01
usually consist of a critical care physician, critical care nurse , and respiratory therapist. A Front-end Analysis has found several problems within...critically ill and wounded. This life-saving mission is executed by CCAT teams, which usually consist of a critical care physician, critical care nurse ...ill and wounded. This life-saving mission is executed by CCAT teams, which usually consist of a critical care physician, critical care nurse , and
The Psychology of Groups: Why Quality and Impartial Leadership Is Critical to a Group's Success.
ERIC Educational Resources Information Center
Campbell, Richard
Many decisions made by outdoor leaders are critical to the well-being of an entire group. Understanding the psychology of groups is important to successful leadership. This paper presents ways that individuals are motivated in groups, how groups respond, some symptoms of problems, and strategies to divert problems that can overwhelm a group.…
ERIC Educational Resources Information Center
Katsioloudis, Petros; Moye, Johnny J.
2012-01-01
The purpose of this research was to determine the future critical issues and problems facing the K-12 technology and engineering education profession in the Commonwealth of Virginia. This study was based on the Wicklein nationwide studies (1993a, 2005). Even though this study did not exactly replicate the Wicklein studies--since it was limited to…
ERIC Educational Resources Information Center
Feierabend, Timo; Eilks, Ingo
2011-01-01
This paper discusses a chemistry lesson plan based on the use of ethanol as an alternative and renewable energy source. The lessons were developed by participatory action research and follow a socio-critical and problem-oriented approach to chemistry teaching. This approach specifically focuses on the handling of scientific and technological…
The Bean model in suprconductivity: Variational formulation and numerical solution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prigozhin, L.
The Bean critical-state model describes the penetration of magnetic field into type-II superconductors. Mathematically, this is a free boundary problem and its solution is of interest in applied superconductivity. We derive a variational formulation for the Bean model and use it to solve two-dimensional and axially symmetric critical-state problems numerically. 25 refs., 9 figs., 1 tab.
ERIC Educational Resources Information Center
Zabit, Mohd Nazir Md
2010-01-01
This review forms the background to explore and to gain empirical support among lecturers to improve the students' critical thinking skills in business education courses in Malaysia, in which the main teaching and learning methodology is Problem-Based Learning (PBL). The PBL educational approach is known to have maximum positive impacts in…
The School Library: A Space for Critical Thinking about Data and Mathematical Questions
ERIC Educational Resources Information Center
Kimmel, Sue C.
2012-01-01
Which potato chip is healthiest: (1) regular; (2) baked; or (3) sour cream and onion? This problem requires critical and numerical skills in order to read and compare nutrition labels. The question has applications in mathematics and science classrooms but also in teachers' lounges and school cafeterias. It is a problem that addresses the five…
ERIC Educational Resources Information Center
Garcia, Criselda G.; Hooper, H. H., Jr.
2011-01-01
The purpose of the qualitative study using a phenomenological approach was to gain insight of preservice teachers' experiences with a WebCT seminar designed to develop critical thinking and problem-solving skills in a Hispanic-Serving Institution's teacher education program. By applying a "holistic approach" to analyze data, NVivo software was…
ERIC Educational Resources Information Center
Kister, Joanna; And Others
This Personal Development Resource Guide is intended to help teachers implement Ohio's Work and Family Life Program. Course content focuses on the practical problems faced by adolescents at the critical stage of their development. These practical problems are posed through case studies and shared experiences and examined using critical questions…
ERIC Educational Resources Information Center
Hyytinen, Heidi; Holma, Katariina; Toom, Auli; Shavelson, Richard J.; Lindblom-Ylänne, Sari
2014-01-01
The study utilized a multi-method approach to explore the connection between critical thinking and epistemological beliefs in a specific problem-solving situation. Data drawn from a sample of ten third-year bioscience students were collected using a combination of a cognitive lab and a performance task from the Collegiate Learning Assessment…
Application of perturbation theory to lattice calculations based on method of cyclic characteristics
NASA Astrophysics Data System (ADS)
Assawaroongruengchot, Monchai
Perturbation theory is a technique used for the estimation of changes in performance functionals, such as linear reaction rate ratio and eigenvalue affected by small variations in reactor core compositions. Here the algorithm of perturbation theory is developed for the multigroup integral neutron transport problems in 2D fuel assemblies with isotropic scattering. The integral transport equation is used in the perturbative formulation because it represents the interconnecting neutronic systems of the lattice assemblies via the tracking lines. When the integral neutron transport equation is used in the formulation, one needs to solve the resulting integral transport equations for the flux importance and generalized flux importance functions. The relationship between the generalized flux importance and generalized source importance functions is defined in order to transform the generalized flux importance transport equations into the integro-differential equations for the generalized adjoints. Next we develop the adjoint and generalized adjoint transport solution algorithms based on the method of cyclic characteristics (MOCC) in DRAGON code. In the MOCC method, the adjoint characteristics equations associated with a cyclic tracking line are formulated in such a way that a closed form for the adjoint angular function can be obtained. The MOCC method then requires only one cycle of scanning over the cyclic tracking lines in each spatial iteration. We also show that the source importance function by CP method is mathematically equivalent to the adjoint function by MOCC method. In order to speed up the MOCC solution algorithm, a group-reduction and group-splitting techniques based on the structure of the adjoint scattering matrix are implemented. A combined forward flux/adjoint function iteration scheme, based on the group-splitting technique and the common use of a large number of variables storing tracking-line data and exponential values, is proposed to reduce the computing time when both direct and adjoint solutions are required. A problem that arises for the generalized adjoint problem is that the direct use of the negative external generalized adjoint sources in the adjoint solution algorithm results in negative generalized adjoint functions. A coupled flux biasing/decontamination scheme is applied to make the generalized adjoint functions positive using the adjoint functions in such a way that it can be used for the multigroup rebalance technique. Next we consider the application of the perturbation theory to the reactor problems. Since the coolant void reactivity (CVR) is a important factor in reactor safety analysis, we have decided to select this parameter for optimization studies. We consider the optimization and adjoint sensitivity techniques for the adjustments of CVR at beginning of burnup cycle (BOC) and k eff at end of burnup cycle (EOC) for a 2D Advanced CANDU Reactor (ACR) lattice. The sensitivity coefficients are evaluated using the perturbation theory based on the integral transport equations. Three sets of parameters for CVR-BOC and keff-EOC adjustments are studied: (1) Dysprosium density in the central pin with Uranium enrichment in the outer fuel rings, (2) Dysprosium density and Uranium enrichment both in the central pin, and (3) the same parameters as in the first case but the objective is to obtain a negative checkerboard CVR at beginning of cycle (CBCVR-BOC). To approximate the sensitivity coefficient at EOC, we perform constant-power burnup/depletion calculations for 600 full power days (FPD) using a slightly perturbed nuclear library and the unperturbed neutron fluxes to estimate the variation of nuclide densities at EOC. Sensitivity analyses of CVR and eigenvalue are included in the study. In addition the optimization and adjoint sensitivity techniques are applied to the CBCVR-BOC and keff-EOC adjustment of the ACR lattices with Gadolinium in the central pin. Finally we apply these techniques to the CVR-BOC, CVR-EOC and keff-EOC adjustment of a CANDU lattice of which the burnup period is extended from 300 to 450 FPDs. The cases with the central pin containing either Dysprosium or Gadolinium in the natural Uranium are considered in our study. (Abstract shortened by UMI.)
Simpson, Elaine; Courtney, Mary
2008-12-01
The purpose of this study was to develop, implement and evaluate critical thinking strategies to enhance critical thinking skills in Middle Eastern nurses. Critical thinking strategies such as questioning, debate, role play and small group activity were developed and used in a professional development programme, which was trialled on a sample of Middle Eastern nurses (n = 20), to promote critical thinking skills, encourage problem solving, development of clinical judgment making and care prioritization in order to improve patient care and outcomes. Classroom learning was transformed from memorization to interaction and active participation. The intervention programme was successful in developing critical thinking skills in both the nurse educators and student nurses in this programme. This programme successfully integrated critical thinking strategies into a Middle Eastern nursing curriculum. Recommendations are as follows: (1) utilize evidence-based practice and stem questions to encourage the formulation of critical thinking questions; (2) support the needs of nurse educators for them to effectively implement teaching strategies to foster critical thinking skills; and (3) adopt creative approaches to (i) transform students into interactive participants and (ii) open students' minds and stimulate higher-level thinking and problem-solving abilities.
Castro-Sánchez, Manuel; Zurita-Ortega, Félix; Chacón-Cuberos, Ramón; López-Gutiérrez, Carlos Javier; Zafra-Santos, Edson
2018-05-01
(1) Background: Psychological factors can strongly affect the athletes’ performance. Therefore, currently the role of the sports psychologist is particularly relevant, being in charge of training the athlete’s psychological factors. This study aims at analysing the connections between motivational climate in sport, anxiety and emotional intelligence depending on the type of sport practised (individual/team) by means of a multigroup structural equations analysis. (2) 372 semi-professional Spanish athletes took part in this investigation, analysing motivational climate (PMCSQ-2), emotional intelligence (SSRI) and levels of anxiety (STAI). A model of multigroup structural equations was carried out which fitted accordingly (χ² = 586.77; df = 6.37; p < 0.001; Comparative Fit Index (CFI) = 0.951; Normed Fit Index (NFI) = 0.938; Incremental Fit Index (IFI) = 0.947; Root Mean Square Error of Approximation (RMSEA) = 0.069). (3) Results: A negative and direct connection has been found between ego oriented climate and task oriented climate, which is stronger and more differentiated in team sports. The most influential indicator in ego oriented climate is intra-group rivalry, exerting greater influence in individual sports. For task-oriented climate the strongest indicator is having an important role in individual sports, while in team sports it is cooperative learning. Emotional intelligence dimensions correlate more strongly in team sports than in individual sports. In addition, there was a negative and indirect relation between task oriented climate and trait-anxiety in both categories of sports. (4) Conclusions: This study shows how the task-oriented motivational climate or certain levels of emotional intelligence can act preventively in the face of anxiety states in athletes. Therefore, the development of these psychological factors could prevent anxiety states and improve performance in athletes.
MacMillan, Freya; Karamacoska, Diana; El Masri, Aymen; McBride, Kate A; Steiner, Genevieve Z; Cook, Amelia; Kolt, Gregory S; Klupp, Nerida; George, Emma S
2017-12-01
To systematically review studies of health promotion intervention in the police force. Four databases were searched for articles reporting on prepost single and multigroup studies in police officers and trainees. Data were extracted and bias assessed to evaluate study characteristics, intervention design and the impact of interventions on health. Database searching identified 25 articles reporting on 21 studies relevant to the aims of this review. Few studies (n=3) were of long duration (≥6 months). Nine of 21 studies evaluated structured physical activity and/or diet programmes only, 5 studies used education and behaviour change support-only interventions, 5 combined structured programmes with education and behaviour change support, and 2 studies used computer prompts to minimise sedentary behaviour. A wide array of lifestyle behaviour and health outcomes was measured, with 11/13 multigroup and 8/8 single-group studies reporting beneficial impacts on outcomes. High risk of bias was evident across most studies. In those with the lowest risk of bias (n=2), a large effect on blood pressure and small effects on diet, sleep quality, stress and tobacco use, were reported. Health promotion interventions can impact beneficially on health of the police force, particularly blood pressure, diet, sleep, stress and tobacco use. Limited reporting made comparison of findings challenging. Combined structured programmes with education and behaviour change support and programmes including peer support resulted in the most impact on health-related outcomes. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
How Much Do Adolescents Cybergossip? Scale Development and Validation in Spain and Colombia.
Romera, Eva M; Herrera-López, Mauricio; Casas, José A; Ortega Ruiz, Rosario; Del Rey, Rosario
2018-01-01
Cybergossip is the act of two or more people making evaluative comments via digital devices about somebody who is not present. This cyberbehavior affects the social group in which it occurs and can either promote or hinder peer relationships. Scientific studies that assess the nature of this emerging and interactive behavior in the virtual world are limited. Some research on traditional gossip has identified it as an inherent and defining element of indirect relational aggression. This paper adopts and argues for a wider definition of gossip that includes positive comments and motivations. This work also suggests that cybergossip has to be measured independently from traditional gossip due to key differences when it occurs through ICT. This paper presents the Colombian and Spanish validation of the Cybergossip Questionnaire for Adolescents (CGQ-A), involving 3,747 high school students ( M = 13.98 years old, SD = 1.69; 48.5% male), of which 1,931 were Colombian and 1,816 were Spanish. Test models derived from item response theory, confirmatory factor analysis, content validation, and multi-group analysis were run on the full sample and subsamples for each country and both genders. The obtained optimal fit and psychometric properties confirm the robustness and suitability of a one-dimensional structure for the cybergossip instrument. The multi-group analysis shows that the cybergossip construct is understood similarly in both countries and between girls and boys. The composite reliability ratifies convergent and divergent validity of the scale. Descriptive results show that Colombian adolescents gossip less than their Spanish counterparts and that boys and girls use cybergossip to the same extent. As a conclusion, this study confirmes the relationship between cybergossip and cyberbullying, but it also supports a focus on positive cybergossip in psychoeducational interventions to build positive virtual relationships and prevent risky cyberbehaviors.
Lin, Chung-Ying; Griffiths, Mark D; Pakpour, Amir H
2018-03-01
Background and aims Research examining problematic mobile phone use has increased markedly over the past 5 years and has been related to "no mobile phone phobia" (so-called nomophobia). The 20-item Nomophobia Questionnaire (NMP-Q) is the only instrument that assesses nomophobia with an underlying theoretical structure and robust psychometric testing. This study aimed to confirm the construct validity of the Persian NMP-Q using Rasch and confirmatory factor analysis (CFA) models. Methods After ensuring the linguistic validity, Rasch models were used to examine the unidimensionality of each Persian NMP-Q factor among 3,216 Iranian adolescents and CFAs were used to confirm its four-factor structure. Differential item functioning (DIF) and multigroup CFA were used to examine whether males and females interpreted the NMP-Q similarly, including item content and NMP-Q structure. Results Each factor was unidimensional according to the Rach findings, and the four-factor structure was supported by CFA. Two items did not quite fit the Rasch models (Item 14: "I would be nervous because I could not know if someone had tried to get a hold of me;" Item 9: "If I could not check my smartphone for a while, I would feel a desire to check it"). No DIF items were found across gender and measurement invariance was supported in multigroup CFA across gender. Conclusions Due to the satisfactory psychometric properties, it is concluded that the Persian NMP-Q can be used to assess nomophobia among adolescents. Moreover, NMP-Q users may compare its scores between genders in the knowledge that there are no score differences contributed by different understandings of NMP-Q items.
Release of Continuous Representation for S(α,β) ACE Data
DOE Office of Scientific and Technical Information (OSTI.GOV)
Conlin, Jeremy Lloyd; Parsons, Donald Kent
2014-03-20
For low energy neutrons, the default free gas model for scattering cross sections is not always appropriate. Molecular effects or crystalline structure effects can affect the neutron scattering cross sections. These effects are included in the S(α; β) thermal neutron scattering data and are tabulated in file 7 of the ENDF6 format files. S stands for scattering. α is a momentum transfer variable and is an energy transfer variable. The S(α; β) cross sections can include coherent elastic scattering (no E change for the neutron, but specific scattering angles), incoherent elastic scattering (no E change for the neutron, but continuousmore » scattering angles), and inelastic scattering (E change for the neutron, and change in angle as well). Every S(α; β) material will have inelastic scattering and may have either coherent or incoherent elastic scattering (but not both). Coherent elastic scattering cross sections have distinctive jagged-looking Bragg edges, whereas the other cross sections are much smoother. The evaluated files from the NNDC are processed locally in the THERMR module of NJOY. Data can be produced either for continuous energy Monte Carlo codes (using ACER) or embedded in multi-group cross sections for deterministic (or even multi-group Monte Carlo) codes (using GROUPR). Currently, the S(α; β) files available for MCNP use discrete energy changes for inelastic scattering. That is, the scattered neutrons can only be emitted at specific energies— rather than across a continuous spectrum of energies. The discrete energies are chosen to preserve the average secondary neutron energy, i.e., in an integral sense, but the discrete treatment does not preserve any differential quantities in energy or angle.« less
Year End Progress Report on Rattlesnake Improvements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Yaqi; DeHart, Mark David; Gleicher, Frederick Nathan
Rattlesnake is a MOOSE-based radiation transport application developed at INL to support modern multi-physics simulations. At the beginning of the last year, Rattlesnake was able to perform steady-state, transient and eigenvalue calculations for the multigroup radiation transport equations. Various discretization schemes, including continuous finite element method (FEM) with discrete ordinates method (SN) and spherical harmonics expansion method (PN) for the self-adjoint angular flux (SAAF) formulation, continuous FEM (CFEM) with SN for the least square (LS) formulation, diffusion approximation with CFEM and discontinuous FEM (DFEM), have been implemented. A separate toolkit, YAKXS, for multigroup cross section management was developed to supportmore » Rattlesnake calculations with feedback both from changes in the field variables, such as fuel temperature, coolant density, and etc., and in isotope inventory. The framework for doing nonlinear diffusion acceleration (NDA) within Rattlesnake has been set up, and both NDA calculations with SAAF-SN-CFEM scheme and Monte Carlo with OpenMC have been performed. It was also used for coupling BISON and RELAP-7 for the full-core multiphysics simulations. Within the last fiscal year, significant improvements have been made in Rattlesnake. Rattlesnake development was migrated into our internal GITLAB development environment at the end of year 2014. Since then total 369 merge requests has been accepted into Rattlesnake. It is noted that the MOOSE framework that Rattlesnake is based on is under continuous developments. Improvements made in MOOSE can improve the Rattlesnake. It is acknowledged that MOOSE developers spent efforts on patching Rattlesnake for the improvements made on the framework side. This report will not cover the code restructuring for better readability and modularity and documentation improvements, which we have spent tremendous effort on. It only details some of improvements in the following sections.« less
López-Gutiérrez, Carlos Javier; Zafra-Santos, Edson
2018-01-01
(1) Background: Psychological factors can strongly affect the athletes’ performance. Therefore, currently the role of the sports psychologist is particularly relevant, being in charge of training the athlete’s psychological factors. This study aims at analysing the connections between motivational climate in sport, anxiety and emotional intelligence depending on the type of sport practised (individual/team) by means of a multigroup structural equations analysis. (2) 372 semi-professional Spanish athletes took part in this investigation, analysing motivational climate (PMCSQ-2), emotional intelligence (SSRI) and levels of anxiety (STAI). A model of multigroup structural equations was carried out which fitted accordingly (χ2 = 586.77; df = 6.37; p < 0.001; Comparative Fit Index (CFI) = 0.951; Normed Fit Index (NFI) = 0.938; Incremental Fit Index (IFI) = 0.947; Root Mean Square Error of Approximation (RMSEA) = 0.069). (3) Results: A negative and direct connection has been found between ego oriented climate and task oriented climate, which is stronger and more differentiated in team sports. The most influential indicator in ego oriented climate is intra-group rivalry, exerting greater influence in individual sports. For task-oriented climate the strongest indicator is having an important role in individual sports, while in team sports it is cooperative learning. Emotional intelligence dimensions correlate more strongly in team sports than in individual sports. In addition, there was a negative and indirect relation between task oriented climate and trait-anxiety in both categories of sports. (4) Conclusions: This study shows how the task-oriented motivational climate or certain levels of emotional intelligence can act preventively in the face of anxiety states in athletes. Therefore, the development of these psychological factors could prevent anxiety states and improve performance in athletes. PMID:29724008
Assari, Shervin; Moazen-Zadeh, Ehsan; Caldwell, Cleopatra Howard; Zimmerman, Marc A
2017-01-01
Despite the existing knowledge regarding the negative mental health consequences of perceived racial discrimination, very few researchers have used a longitudinal design with long-term follow-up periods to explore gender differences in this association over time. The current longitudinal study aimed to investigate gender differences in predictive role of an increase in perceived racial discrimination during adolescence for mental health deterioration a decade later when they are transitioning to young adulthood. Current study followed 681 Black youths for 18 years from 1994 (mean age 15) to 2012 (mean age 32). All participants spent their adolescence and transition to young adulthood in an economically disadvantaged urban area in the Midwest of the United States. Independent variable was perceived racial discrimination measured in 1999 and 2002. Outcomes were psychological symptoms (anxiety and depression) measured in 1999 and at end of follow-up (2012). Covariates included sociodemographics (age, family structure, and parental employment) measured in 1994. Gender was used to define groups in a multigroup structural equation model to test moderating effects. Multigroup structural equation modeling showed that among male Black youth, an increase in perceived racial discrimination from age 20 to 23 was predictive for an increase in symptoms of anxiety and depression from age 20 to 32. Among female Black youth, change in perceived racial discrimination did not predict future change in depressive or anxiety symptoms. While racial discrimination is associated with negative mental health consequences for both genders, male and female Black youth differ in regard to long-term effects of an increase in perceived discrimination on deterioration of psychological symptoms. Black males seem to be more susceptible than Black females to the psychological effects of an increase in racial discrimination over time.
Tayyeb, Rakhshanda
2013-01-01
To assess effectiveness of PBL as an instructional tool in clinical years to improve learning of undergraduate students in terms of acquisition of content knowledge, critical thinking and problem solving skills through problem based learning and traditional way of teaching. Quasi-experimental study. Fatima Jinnah Medical College for Women, Lahore, from October 2009 to April 2010. Final year medical students attending Obstetrics and Gynaecology and Surgery rotations were inducted as participants in this study. Two batches of 50 students each attended Gynaecology rotation and two batches attended Surgery rotation, i.e. 100 students in each. Each batch was divided into two groups i.e. A and B of 25 students each. Group-A learnt through traditional teaching, involving bedside teaching and lectures in wards and Group-B learnt relevant clinical knowledge through a modified PBL process. Content knowledge was tested by MCQs testing recall while clinical reasoning and problem were assessed by MCQs testing analysis and critical thinking. Intra-group comparison of mean scores of pre and post-test scores was done using paired sample t-tests while for intergroup comparison of mean scores was done through independent sample t-test. Teaching through traditional method significantly improved content knowledge, (p = 0.001) but did not considerably improve clinical reasoning and problem solving skills (p = 0.093) whereas, content knowledge of students who studied through PBL remained the same (p = 0.202) but there was marked improvement in their clinical reasoning and problem solving skills (p = < 0.001). PBL is an effective instructional tool to foster critical thinking and problem solving skills among medical students.
The Use of Argument Mapping to Enhance Critical Thinking Skills in Business Education
ERIC Educational Resources Information Center
Kunsch, David W.; Schnarr, Karin; van Tyle, Russell
2014-01-01
Complex business problems require enhanced critical thinking skills. In a dedicated, in-person critical thinking class, argument mapping techniques were used in conjunction with business and nonbusiness case studies to build the critical thinking skills of a group of master of business administration students. Results demonstrated that the…
Critical Thinking and the Critical Person.
ERIC Educational Resources Information Center
Paul, Richard W.
The paper's purpose is to clarify and develop some theoretical and practical implications of the concept of critical thinking, and the field of social studies is used as one example of the problem. The work of four leading critical theorists (Robert Ennis, Harvey Siegel, Michael Scriven, and R. S. Peters) is described and a distinction is made…
Real-World Problems: Engaging Young Learners in Critical Thinking
ERIC Educational Resources Information Center
Cole, Bronwyn; McGuire, Margit
2012-01-01
Critical thinking is a process that can be taught. It involves "evaluating the accuracy, credibility, and worth of information and lines of reasoning. Critical thinking is reflective, logical, evidence-based, and has a purposeful quality to it--that is, the learner thinks critically in order to achieve a particular goal." The authors have found…
ERIC Educational Resources Information Center
McKinley, Jim
2013-01-01
This article provides an examination of the literature on issues surrounding the problems Japanese university students face in learning critical argument in their English academic writing courses. Japanese students' critical thinking skills are criticized as not fostered in their university education, perhaps due to Confucian education ideals,…
Congruency in Defining Critical Thinking by Nurse Educators and Non-nurse Scholars.
ERIC Educational Resources Information Center
Gordon, Joanne M.
2000-01-01
Nurse educators (n=201) identified their concept of critical thinking and agreement with nonnurse experts (a Delphi panel of academic scholars) on critical thinking items. They agreed on skills and dispositions, but nurse educators were more likely to consider research, problem solving, decision making, and planning as critical thinking…
Teaching Understanding and Developing Critical Thinking.
ERIC Educational Resources Information Center
Eulie, Joseph
1988-01-01
Examines the relationship between teaching content or knowledge, and teaching the skills of critical thinking and problem solving. Presents key strategies to help students understand and develop critical thinking skills. Recommends use of the developmental lesson and provides several model lessons. (LS)
Automatic yield-line analysis of slabs using discontinuity layout optimization
Gilbert, Matthew; He, Linwei; Smith, Colin C.; Le, Canh V.
2014-01-01
The yield-line method of analysis is a long established and extremely effective means of estimating the maximum load sustainable by a slab or plate. However, although numerous attempts to automate the process of directly identifying the critical pattern of yield-lines have been made over the past few decades, to date none has proved capable of reliably analysing slabs of arbitrary geometry. Here, it is demonstrated that the discontinuity layout optimization (DLO) procedure can successfully be applied to such problems. The procedure involves discretization of the problem using nodes inter-connected by potential yield-line discontinuities, with the critical layout of these then identified using linear programming. The procedure is applied to various benchmark problems, demonstrating that highly accurate solutions can be obtained, and showing that DLO provides a truly systematic means of directly and reliably automatically identifying yield-line patterns. Finally, since the critical yield-line patterns for many problems are found to be quite complex in form, a means of automatically simplifying these is presented. PMID:25104905