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Sample records for engagement criterion predict

  1. A Comparison of Three Job Engagement Measures: Examining their Factorial and Criterion-Related Validity.

    Science.gov (United States)

    Wefald, Andrew J; Mills, Maura J; Smith, Michael R; Downey, Ronald G

    2012-03-01

    Engagement is an emerging job attitude that purports to measure employees' psychological presence at and involvement in their work. This research compares three academic approaches to engagement, and makes recommendations regarding the most appropriate conceptualisation and measurement of the construct in future research. The current research also investigates whether any of these three approaches to engagement contribute unique variance to the prediction of turnover intentions above and beyond the predictive capacity of alternative constructs. An online survey was taken by 382 employees and managers from a mid-sized financial institution. Results failed to support either a multi- or unidimensional factor structure for the Utrecht Work Engagement Scale (UWES) engagement measure. For the Shirom-Melamed Vigor Measure (SMVM), a multi-dimensional structure was identified as a good fit, while a unidimensional structure fit poorly. The uni-factorial structure of Britt's engagement measure was confirmed. The Schaufeli measure of engagement was a strong predictor of work outcomes; however, when controlling for job satisfaction and affective commitment, that measure lost its ability to predict intentions to leave. Two components of the Shirom vigor measure held their predictive validity. Collectively, these findings suggest that the Shirom vigor measure may provide better insight into whether and how much a person is 'into' his or her job. The Schaufeli measure was a good predictor of important work outcomes, but when job satisfaction and affective commitment were controlled, it lost its predictive validity. We were not able to confirm the three-factor structure of the Schaufeli measure. Two components of the Shirom vigor measure predicted turnover intentions after controlling for job satisfaction and affective commitment, suggesting less overlap with those constructs than the Schaufeli measure of engagement. This research adds important information on the nature of

  2. Prediction of Hot Tearing Using a Dimensionless Niyama Criterion

    Science.gov (United States)

    Monroe, Charles; Beckermann, Christoph

    2014-08-01

    The dimensionless form of the well-known Niyama criterion is extended to include the effect of applied strain. Under applied tensile strain, the pressure drop in the mushy zone is enhanced and pores grow beyond typical shrinkage porosity without deformation. This porosity growth can be expected to align perpendicular to the applied strain and to contribute to hot tearing. A model to capture this coupled effect of solidification shrinkage and applied strain on the mushy zone is derived. The dimensionless Niyama criterion can be used to determine the critical liquid fraction value below which porosity forms. This critical value is a function of alloy properties, solidification conditions, and strain rate. Once a dimensionless Niyama criterion value is obtained from thermal and mechanical simulation results, the corresponding shrinkage and deformation pore volume fractions can be calculated. The novelty of the proposed method lies in using the critical liquid fraction at the critical pressure drop within the mushy zone to determine the onset of hot tearing. The magnitude of pore growth due to shrinkage and deformation is plotted as a function of the dimensionless Niyama criterion for an Al-Cu alloy as an example. Furthermore, a typical hot tear "lambda"-shaped curve showing deformation pore volume as a function of alloy content is produced for two Niyama criterion values.

  3. A New Criterion for Prediction of Hot Tearing Susceptibility of Cast Alloys

    Science.gov (United States)

    Nasresfahani, Mohamad Reza; Niroumand, Behzad

    2014-08-01

    A new criterion for prediction of hot tearing susceptibility of cast alloys is suggested which takes into account the effects of both important mechanical and metallurgical factors and is believed to be less sensitive to the presence of volume defects such as bifilms and inclusions. The criterion was validated by studying the hot tearing tendency of Al-Cu alloy. In conformity with the experimental results, the new criterion predicted reduction of hot tearing tendency with increasing the copper content.

  4. The mean lung dose (MLD). Predictive criterion for lung damage

    Energy Technology Data Exchange (ETDEWEB)

    Geyer, Peter; Appold, Steffen [Dresden University of Technology (TU Dresden), Clinic and Polyclinic for Radiotherapy and Radiation Oncology, Carl Gustav Carus Medical Faculty, Dresden (Germany); Herrmann, Thomas

    2015-07-15

    The purpose of this work was to prove the validity of the mean lung dose (MLD), widely used in clinical practice to estimate the lung toxicity of a treatment plan, by reevaluating experimental data from mini pigs. A total of 43 mini pigs were irradiated in one of four dose groups (25, 29, 33, and 37 Gy). Two regimens were applied: homogeneous irradiation of the right lung or partial irradiation of both lungs - including parts with lower dose - but with similar mean lung doses. The animals were treated with five fractions with a linear accelerator applying a CT-based treatment plan. The clinical lung reaction (breathing frequency) and morphological changes in CT scans were examined frequently during the 48 weeks after irradiation. A clear dose-effect relationship was found for both regimens of the trial. However, a straightforward relationship between the MLD and the relative number of responders with respect to different grades of increased breathing frequency for both regimens was not found. A morphologically based parameter NTCP{sub lung} was found to be more suitable for this purpose. The dependence of this parameter on the MLD is markedly different for the two regimens. In clinical practice, the MLD can be used to predict lung toxicity of a treatment plan, except for dose values that could lead to severe side effects. In the latter mentioned case, limitations to the predictive value of the MLD are possible. Such severe developments of a radiation-induced pneumopathy are better predicted by the NTCP{sub lung} formalism. The predictive advantage of this parameter compared to the MLD seems to remain in the evaluation and comparison of widely differing dose distributions, like in the investigated trial. (orig.) [German] Es soll unter Reevaluation von Tierversuchsdaten am Minischwein geprueft werden, ob die in der klinischen Praxis zur Beurteilung der Lungentoxizitaet eines Bestrahlungsregims regelhaft verwendete mittlere Lungendosis (MLD) eine zuverlaessige

  5. A critical analysis of the Mises stress criterion used in frequency domain fatigue life prediction

    Directory of Open Access Journals (Sweden)

    Adam Niesłony

    2016-10-01

    Full Text Available Multiaxial fatigue failure criteria are formulated in time and frequency domain. The number of frequency domain criteria is rather small and the most popular one is the equivalent von Mises stress criterion. This criterion was elaborated by Preumont and Piefort on the basis of well-known von Mises stress concept, first proposed by Huber in 1907, and well accepted by the scientific community and engineers. It is important to know, that the criterion was developed to determine the yield stress and material effort under static load. Therefore the direct use of equivalent von Mises stress criterion for fatigue life prediction can lead to some incorrectness of theoretical and practical nature. In the present study four aspects were discussed: influence of the value of fatigue strength of tension and torsion, lack of parallelism of the SN curves, abnormal behaviour of the criterion under biaxial tensioncompression and influence of phase shift between particular stress state components. Information contained in this article will help to prevent improper use of this criterion and contributes to its better understanding

  6. A simple criterion to predict the glass forming ability of metallic alloys

    International Nuclear Information System (INIS)

    Falcao de Oliveira, Marcelo

    2012-01-01

    A new and simple criterion with which to quantitatively predict the glass forming ability (GFA) of metallic alloys is proposed. It was found that the critical cooling rate for glass formation (R C ) correlates well with a proper combination of two factors, the minimum topological instability (λ min ) and the Δh parameter, which depends on the average work function difference (Δφ) and the average electron density difference (Δn ws 1/3 ) among the constituent elements of the alloy. A correlation coefficient (R 2 ) of 0.76 was found between R c and the new criterion for 68 alloys in 30 different metallic systems. The new criterion and the Uhlmann's approach were used to estimate the critical amorphous thickness (Z C ) of alloys in the Cu-Zr system. The new criterion underestimated R C in the Cu-Zr system, producing predicted Z C values larger than those observed experimentally. However, when considering a scale factor, a remarkable similarity was observed between the predicted and the experimental behavior of the GFA in the binary Cu-Zr. When using the same scale factor and performing the calculation for the ternary Zr-Cu-Al, good agreement was found between the predicted and the actual best GFA region, as well as between the expected and the observed critical amorphous thickness.

  7. Earing Prediction in Cup Drawing using the BBC2008 Yield Criterion

    Science.gov (United States)

    Vrh, Marko; Halilovič, Miroslav; Starman, Bojan; Štok, Boris; Comsa, Dan-Sorin; Banabic, Dorel

    2011-08-01

    The paper deals with constitutive modelling of highly anisotropic sheet metals. It presents FEM based earing predictions in cup drawing simulation of highly anisotropic aluminium alloys where more than four ears occur. For that purpose the BBC2008 yield criterion, which is a plane-stress yield criterion formulated in the form of a finite series, is used. Thus defined criterion can be expanded to retain more or less terms, depending on the amount of given experimental data. In order to use the model in sheet metal forming simulations we have implemented it in a general purpose finite element code ABAQUS/Explicit via VUMAT subroutine, considering alternatively eight or sixteen parameters (8p and 16p version). For the integration of the constitutive model the explicit NICE (Next Increment Corrects Error) integration scheme has been used. Due to the scheme effectiveness the CPU time consumption for a simulation is comparable to the time consumption of built-in constitutive models. Two aluminium alloys, namely AA5042-H2 and AA2090-T3, have been used for a validation of the model. For both alloys the parameters of the BBC2008 model have been identified with a developed numerical procedure, based on a minimization of the developed cost function. For both materials, the predictions of the BBC2008 model prove to be in very good agreement with the experimental results. The flexibility and the accuracy of the model together with the identification and integration procedure guarantee the applicability of the BBC2008 yield criterion in industrial applications.

  8. Failure criterion effect on solid production prediction and selection of completion solution

    Directory of Open Access Journals (Sweden)

    Dariush Javani

    2017-12-01

    Full Text Available Production of fines together with reservoir fluid is called solid production. It varies from a few grams or less per ton of reservoir fluid posing only minor problems, to catastrophic amount possibly leading to erosion and complete filling of the borehole. This paper assesses solid production potential in a carbonate gas reservoir located in the south of Iran. Petrophysical logs obtained from the vertical well were employed to construct mechanical earth model. Then, two failure criteria, i.e. Mohr–Coulomb and Mogi–Coulomb, were used to investigate the potential of solid production of the well in the initial and depleted conditions of the reservoir. Using these two criteria, we estimated critical collapse pressure and compared them to the reservoir pressure. Solid production occurs if collapse pressure is greater than pore pressure. Results indicate that the two failure criteria show different estimations of solid production potential of the studied reservoir. Mohr–Coulomb failure criterion estimated solid production in both initial and depleted conditions, where Mogi–Coulomb criterion predicted no solid production in the initial condition of reservoir. Based on Mogi–Coulomb criterion, the well may not require completion solutions like perforated liner, until at least 60% of reservoir pressure was depleted which leads to decrease in operation cost and time.

  9. Facial motion engages predictive visual mechanisms.

    Directory of Open Access Journals (Sweden)

    Jordy Kaufman

    Full Text Available We employed a novel cuing paradigm to assess whether dynamically versus statically presented facial expressions differentially engaged predictive visual mechanisms. Participants were presented with a cueing stimulus that was either the static depiction of a low intensity expressed emotion; or a dynamic sequence evolving from a neutral expression to the low intensity expressed emotion. Following this cue and a backwards mask, participants were presented with a probe face that displayed either the same emotion (congruent or a different emotion (incongruent with respect to that displayed by the cue although expressed at a high intensity. The probe face had either the same or different identity from the cued face. The participants' task was to indicate whether or not the probe face showed the same emotion as the cue. Dynamic cues and same identity cues both led to a greater tendency towards congruent responding, although these factors did not interact. Facial motion also led to faster responding when the probe face was emotionally congruent to the cue. We interpret these results as indicating that dynamic facial displays preferentially invoke predictive visual mechanisms, and suggest that motoric simulation may provide an important basis for the generation of predictions in the visual system.

  10. Using the Predictability Criterion for Selecting Extended Verbs for Shona Dictionaries

    Directory of Open Access Journals (Sweden)

    Emmanuel Chabata

    2012-09-01

    Full Text Available

    The paper examines the "predictability criterion", a classificatory tool which is used in selecting affixed word forms for dictionary entries. It focuses on the criterion as it has been used by the African Languages Lexical (ALLEX Project for selecting extended verbs to enter as headwords in the Project's first monolingual Shona dictionary Duramazwi ReChiShona. The article also examines the status of Shona verbal extensions in terms of their semantic input to the verb stems they are attached to. The paper was originally motivated by two observations: (a that predictability seems to be a matter of degree; and (b that the predictability criterion tended to be used inconsistently in the selection of extended verbs and senses for Duramazwi ReChiShona. An analysis of 412 productively extended verbs that were entered as headwords in Duramazwi ReChiShona shows that verbal extensions can bring both predictable and unpredictable senses to the verb stems they are attached to. The paper demonstrates that for an effective use of the predictability criterion for selecting extended verbs for Shona dictionaries, there is need for the lexicographer to have an in-depth understanding of the kinds of semantic movements that are caused when verb stems are extended. It shows the need to view verbal extensions in Shona as derivational morphemes, not inflectional morphemes as some earlier scholars have concluded.

     

     

    Die gebruik van die voorspelbaarheidskriterium om uitgebreide werkwoorde te selekteer vir Shonawoordeboeke

    Hierdie artikel ondersoek die "voorspelbaarheidskriterium", 'n klassifikasiehulpmiddel wat gebruik word om geaffigeerde woordvorme te selekteer as woordeboekinskrywings. Dit fokus op die kriterium soos dit gebruik is deur die African Language Lexical (ALLEX Project vir die selektering van uitgebreide werkwoorde as lemmas in die Projek se eerste eentalige Shonawoordeboek Duramazwi ReChiShona. In

  11. Genetic Gain Increases by Applying the Usefulness Criterion with Improved Variance Prediction in Selection of Crosses.

    Science.gov (United States)

    Lehermeier, Christina; Teyssèdre, Simon; Schön, Chris-Carolin

    2017-12-01

    A crucial step in plant breeding is the selection and combination of parents to form new crosses. Genome-based prediction guides the selection of high-performing parental lines in many crop breeding programs which ensures a high mean performance of progeny. To warrant maximum selection progress, a new cross should also provide a large progeny variance. The usefulness concept as measure of the gain that can be obtained from a specific cross accounts for variation in progeny variance. Here, it is shown that genetic gain can be considerably increased when crosses are selected based on their genomic usefulness criterion compared to selection based on mean genomic estimated breeding values. An efficient and improved method to predict the genetic variance of a cross based on Markov chain Monte Carlo samples of marker effects from a whole-genome regression model is suggested. In simulations representing selection procedures in crop breeding programs, the performance of this novel approach is compared with existing methods, like selection based on mean genomic estimated breeding values and optimal haploid values. In all cases, higher genetic gain was obtained compared with previously suggested methods. When 1% of progenies per cross were selected, the genetic gain based on the estimated usefulness criterion increased by 0.14 genetic standard deviation compared to a selection based on mean genomic estimated breeding values. Analytical derivations of the progeny genotypic variance-covariance matrix based on parental genotypes and genetic map information make simulations of progeny dispensable, and allow fast implementation in large-scale breeding programs. Copyright © 2017 by the Genetics Society of America.

  12. Prediction of fracture initiation in square cup drawing of DP980 using an anisotropic ductile fracture criterion

    Science.gov (United States)

    Park, N.; Huh, H.; Yoon, J. W.

    2017-09-01

    This paper deals with the prediction of fracture initiation in square cup drawing of DP980 steel sheet with the thickness of 1.2 mm. In an attempt to consider the influence of material anisotropy on the fracture initiation, an uncoupled anisotropic ductile fracture criterion is developed based on the Lou—Huh ductile fracture criterion. Tensile tests are carried out at different loading directions of 0°, 45°, and 90° to the rolling direction of the sheet using various specimen geometries including pure shear, dog-bone, and flat grooved specimens so as to calibrate the parameters of the proposed fracture criterion. Equivalent plastic strain distribution on the specimen surface is computed using Digital Image Correlation (DIC) method until surface crack initiates. The proposed fracture criterion is implemented into the commercial finite element code ABAQUS/Explicit by developing the Vectorized User-defined MATerial (VUMAT) subroutine which features the non-associated flow rule. Simulation results of the square cup drawing test clearly show that the proposed fracture criterion is capable of predicting the fracture initiation with sufficient accuracy considering the material anisotropy.

  13. Use of the Niyama criterion to predict porosity of the mushy zone with deformation

    Directory of Open Access Journals (Sweden)

    S. Polyakov

    2011-10-01

    Full Text Available The article presents new results on the use of the Niyama criterion to estimate porosity appearance in castings under hindered shrinkage. The effect of deformation of the mushy zone on filtration is shown. A new form of the Niyama criterion accounting for the hindered shrinkage and the range of deformation localization has been obtained. The results of this study are illustrated by the examp le of the Niyama criterion calculated for Al-Cu alloys under different diffusion conditions of solidification and rate of deformation in the mushy zone. Derived equations can be used in a mathematical model of the casting solidification as well as for interpretation of the simulation results of casting solidification under hindered shrinkage. The presented study resulted in a new procedure of using the Niyama criterion under mushy zone deformation.

  14. What Predicts Use of Learning-Centered, Interactive Engagement Methods?

    Science.gov (United States)

    Madson, Laura; Trafimow, David; Gray, Tara; Gutowitz, Michael

    2014-01-01

    What makes some faculty members more likely to use interactive engagement methods than others? We use the theory of reasoned action to predict faculty members' use of interactive engagement methods. Results indicate that faculty members' beliefs about the personal positive consequences of using these methods (e.g., "Using interactive…

  15. Prediction of forming limit in hydro-mechanical deep drawing of steel sheets using ductile fracture criterion

    Science.gov (United States)

    Oh, S.-T.; Chang, H.-J.; Oh, K. H.; Han, H. N.

    2006-04-01

    It has been observed that the forming limit curve at fracture (FLCF) of steel sheets, with a relatively higher ductility limit have linear shapes, similar to those of a bulk forming process. In contrast, the FLCF of sheets with a relatively lower ductility limit have rather complex shapes approaching the forming limit curve at neck (FLCN) towards the equi-biaxial strain paths. In this study, the FLCFs of steel sheets were measured and compared with the fracture strains predicted from specific ductile fracture criteria, including a criterion suggested by the authors, which can accurately describe FLCFs with both linear and complex shapes. To predict the forming limit for hydro-mechanical deep drawing of steel sheets, the ductile fracture criteria were integrated into a finite element simulation. The simulation, results based on the criterion suggested by authors accurately predicted the experimetal, fracture limits of steel sheets for the hydro-mechanical deep drawing process.

  16. An Empirical Model Building Criterion Based on Prediction with Applications in Parametric Cost Estimation.

    Science.gov (United States)

    1980-08-01

    varia- ble is denoted by 7, the total sum of squares of deviations from that mean is defined by n - SSTO - (-Y) (2.6) iul and the regression sum of...squares by SSR - SSTO - SSE (2.7) II 14 A selection criterion is a rule according to which a certain model out of the 2p possible models is labeled "best...dis- cussed next. 1. The R2 Criterion The coefficient of determination is defined by R2 . 1 - SSE/ SSTO . (2.8) It is clear that R is the proportion of

  17. Evaluation of probabilistic flow predictions in sewer systems using grey box models and a skill score criterion

    DEFF Research Database (Denmark)

    Thordarson, Fannar Ørn; Breinholt, Anders; Møller, Jan Kloppenborg

    2012-01-01

    term and a diffusion term, respectively accounting for the deterministic and stochastic part of the models. Furthermore, a distinction is made between the process noise and the observation noise. We compare five different model candidates’ predictive performances that solely differ with respect...... to the diffusion term description up to a 4 h prediction horizon by adopting the prediction performance measures; reliability, sharpness and skill score to pinpoint the preferred model. The prediction performance of a model is reliable if the observed coverage of the prediction intervals corresponds to the nominal...... coverage of the prediction intervals, i.e. the bias between these coverages should ideally be zero. The sharpness is a measure of the distance between the lower and upper prediction limits, and skill score criterion makes it possible to pinpoint the preferred model by taking into account both reliability...

  18. A NEW CLINICAL PREDICTION CRITERION ACCURATELY DETERMINES A SUBSET OF PATIENTS WITH BILATERAL PRIMARY ALDOSTERONISM BEFORE ADRENAL VENOUS SAMPLING.

    Science.gov (United States)

    Kocjan, Tomaz; Janez, Andrej; Stankovic, Milenko; Vidmar, Gaj; Jensterle, Mojca

    2016-05-01

    Adrenal venous sampling (AVS) is the only available method to distinguish bilateral from unilateral primary aldosteronism (PA). AVS has several drawbacks, so it is reasonable to avoid this procedure when the results would not affect clinical management. Our objective was to identify a clinical criterion that can reliably predict nonlateralized AVS as a surrogate for bilateral PA that is not treated surgically. A retrospective diagnostic cross-sectional study conducted at Slovenian national endocrine referral center included 69 consecutive patients (mean age 56 ± 8 years, 21 females) with PA who underwent AVS. PA was confirmed with the saline infusion test (SIT). AVS was performed sequentially during continuous adrenocorticotrophic hormone (ACTH) infusion. The main outcome measures were variables associated with nonlateralized AVS to derive a clinical prediction rule. Sixty-seven (97%) patients had a successful AVS and were included in the statistical analysis. A total of 39 (58%) patients had nonlateralized AVS. The combined criterion of serum potassium ≥3.5 mmol/L, post-SIT aldosterone AVS. The best overall classification accuracy (50/67 = 75%) was achieved using the post-SIT aldosterone level AVS. Our clinical prediction criterion appears to accurately determine a subset of patients with bilateral PA who could avoid unnecessary AVS and immediately commence with medical treatment.

  19. Applying a new criterion to predict glass forming alloys in the Zr–Ni–Cu ternary system

    Energy Technology Data Exchange (ETDEWEB)

    Déo, L.P., E-mail: leonardopratavieira@gmail.com [Universidade de São Paulo, EESC, SMM - Av. Trabalhador São Carlense, 400 – São Carlos, SP 13566-590 (Brazil); Mendes, M.A.B., E-mail: marcio.andreato@gmail.com [Universidade Federal de São Carlos, DEMa - Rod. Washington Luiz, Km 235 – São Carlos, SP 13565-905 (Brazil); Costa, A.M.S., E-mail: alexmatos1980@gmail.com [Universidade de São Paulo, DEMAR, EEL – Polo Urbo-Industrial Gleba AI-6, s/n – Lorena, SP 12600-970 (Brazil); Campos Neto, N.D., E-mail: nelsonddcn@gmail.com [Universidade de São Paulo, EESC, SMM - Av. Trabalhador São Carlense, 400 – São Carlos, SP 13566-590 (Brazil); Oliveira, M.F. de, E-mail: falcao@sc.usp.br [Universidade de São Paulo, EESC, SMM - Av. Trabalhador São Carlense, 400 – São Carlos, SP 13566-590 (Brazil)

    2013-03-15

    Highlights: ► Calculation to predict and select the glass forming ability (GFA) of metallic alloys in Zr–Ni–Cu system. ► Good correlation between theoretical and experimental GFA samples. ► Combination of X-ray diffraction (XRD) and differential scanning calorimetry (DSC) techniques mainly to characterize the samples. ► Oxygen impurity dramatically reduced the GFA. ► The selection criterion used opens the possibility to obtain new amorphous alloys, reducing the experimental procedures of trial and error. -- Abstract: A new criterion has been recently proposed to predict and select the glass forming ability (GFA) of metallic alloys. It was found that the critical cooling rate for glass formation (R{sub c}) correlates well with a proper combination of two factors, the minimum topological instability (λ{sub min}) and the thermodynamic parameter (Δh). The (λ{sub min}) criterion is based on the concept of topological instability of stable crystalline structures and (Δh) depends on the average work function difference (Δϕ) and the average electron density difference Δn{sub ws}{sup 1/3} among the constituent elements of the alloy. In the present work, the selection criterion was applied in the Zr–Ni–Cu system and its predictability was analyzed experimentally. Ribbon-shaped and splat-shaped samples were produced by melt-spinning and splat-cooling techniques respectively. The crystallization content and behavior were analyzed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC), respectively. The results showed a good correlation between the theoretical GFA values and the amorphous phase percentages found in different alloy compositions.

  20. Development of a New Gradient Based Strain-Criterion for Prediction of Bendability in Quality Assurance and FEA

    Science.gov (United States)

    Denninger, Ralf; Liewald, Mathias; Sindel, Manfred

    2011-08-01

    Numerical simulation systems are more and more used in process development of car bodies. Nowadays, also the hemming process is optimised in FEA. Thus, the analysing of process robustness calls for a failure criterion for the specific bending and hemming load condition. For that purpose the experimental determination of bendability under various pre-load conditions that occur in real production, e.g. during deep drawing in press shop, is content of this contribution. Using these experimental results, a new approach for a strain-gradient based failure criterion for bending operations is presented to optimise bendability prediction. The bending-strain-gradient approach can be used both in production related departments of quality assurance as well as for simulative process design or process validation for vehicle manufacturing planning.

  1. Predicting the required number of training samples. [for remotely sensed image data based on covariance matrix estimate quality criterion of normal distribution

    Science.gov (United States)

    Kalayeh, H. M.; Landgrebe, D. A.

    1983-01-01

    A criterion which measures the quality of the estimate of the covariance matrix of a multivariate normal distribution is developed. Based on this criterion, the necessary number of training samples is predicted. Experimental results which are used as a guide for determining the number of training samples are included. Previously announced in STAR as N82-28109

  2. A phenomenological prediction of dryout based on the churn-to-annular flow transition criterion in uniformly heated vertical tubes

    International Nuclear Information System (INIS)

    Hong, Sung-Deok; Chun, Se-Young; Yang, Sun-Kyu; Chung, Moon-Ki; Lashgari, Farbod

    2000-01-01

    A phenomenological model is proposed to predict dryout in uniformly heated vertical tubes. The major point of the study was refining the initial conditions at the onset of annular flow location that starts the liquid film dryout process. The void fraction at the onset of the annular flow location has been derived from the vapor superficial velocity obtained by the churn-to-annular flow criterion with the help of the void-quality relationship. The thermodynamic equilibrium quality calculated through the iteration of flow quality using the profile-fit model to find the accurate starting point of the annular-flow in a tube. The present method was validated by worldwide data covering wide parametric ranges, a diameter of 5.1-37.5, exit quality over 10%, a flow rate of 183-5261 kg/m 2 -s and a system pressure of 0.5-17.7 MPa. The churn-to-annular flow transition criterion of Taitel et al.'s shows better prediction results than the other transition criteria. The present model improved the CHF prediction capability as a mean of 0.97 and root mean square error of 11% for the 3883 experimental data and extended the applicable range to the relatively low quality region. (author)

  3. Predicting initial client engagement with community mental health services by routinely measured data

    NARCIS (Netherlands)

    Roeg, D.P.K.; van de Goor, L.A.M.; Garretsen, H.F.L.

    2015-01-01

    Engagement is a determinant of how well a person will respond to professional input. This study investigates whether, in practice, routinely measured data predict initial client engagement with community mental health services. Engagement, problem severity, client characteristics, and duration

  4. Body composition in elderly people: effect of criterion estimates on predictive equations

    International Nuclear Information System (INIS)

    Baumgartner, R.N.; Heymsfield, S.B.; Lichtman, S.; Wang, J.; Pierson, R.N. Jr.

    1991-01-01

    The purposes of this study were to determine whether there are significant differences between two- and four-compartment model estimates of body composition, whether these differences are associated with aqueous and mineral fractions of the fat-free mass (FFM); and whether the differences are retained in equations for predicting body composition from anthropometry and bioelectric resistance. Body composition was estimated in 98 men and women aged 65-94 y by using a four-compartment model based on hydrodensitometry, 3 H 2 O dilution, and dual-photon absorptiometry. These estimates were significantly different from those obtained by using Siri's two-compartment model. The differences were associated significantly (P less than 0.0001) with variation in the aqueous fraction of FFM. Equations for predicting body composition from anthropometry and resistance, when calibrated against two-compartment model estimates, retained these systematic errors. Equations predicting body composition in elderly people should be calibrated against estimates from multicompartment models that consider variability in FFM composition

  5. Forming limit prediction by an evolving non-quadratic yield criterion considering the anisotropic hardening and r-value evolution

    Science.gov (United States)

    Lian, Junhe; Shen, Fuhui; Liu, Wenqi; Münstermann, Sebastian

    2018-05-01

    The constitutive model development has been driven to a very accurate and fine-resolution description of the material behaviour responding to various environmental variable changes. The evolving features of the anisotropic behaviour during deformation, therefore, has drawn particular attention due to its possible impacts on the sheet metal forming industry. An evolving non-associated Hill48 (enHill48) model was recently proposed and applied to the forming limit prediction by coupling with the modified maximum force criterion. On the one hand, the study showed the significance to include the anisotropic evolution for accurate forming limit prediction. On the other hand, it also illustrated that the enHill48 model introduced an instability region that suddenly decreases the formability. Therefore, in this study, an alternative model that is based on the associated flow rule and provides similar anisotropic predictive capability is extended to chapter the evolving effects and further applied to the forming limit prediction. The final results are compared with experimental data as well as the results by enHill48 model.

  6. Engaging Students Emotionally: The Role of Emotional Intelligence in Predicting Cognitive and Affective Engagement in Higher Education

    Science.gov (United States)

    Maguire, Rebecca; Egan, Arlene; Hyland, Philip; Maguire, Phil

    2017-01-01

    Student engagement is a key predictor of academic performance, persistence and retention in higher education. While many studies have identified how aspects of the college environment influence engagement, fewer have specifically focused on emotional intelligence (EI). In this study, we sought to explore whether EI could predict cognitive and/or…

  7. Interpretation of ongoing thermal response tests of vertical (BHE) borehole heat exchangers with predictive uncertainty based stopping criterion

    DEFF Research Database (Denmark)

    Poulsen, Søren Erbs; Alberdi Pagola, Maria

    2015-01-01

    A method for real-time interpretation of ongoing thermal response tests of vertical borehole heat exchangers is presented. The method utilizes a statistically based stopping criterion for ongoing tests. The study finds minimum testing times for synthetic and actual TRTs to be in the interval 12–2...

  8. Clinical assessment scoring system for tracheostomy (CASST) criterion: Objective criteria to predict pre-operatively the need for a tracheostomy in head and neck malignancies.

    Science.gov (United States)

    Gupta, Karan; Mandlik, Dushyant; Patel, Daxesh; Patel, Purvi; Shah, Bankim; Vijay, Devanhalli G; Kothari, Jagdish M; Toprani, Rajendra B; Patel, Kaustubh D

    2016-09-01

    Tracheostomy is a mainstay modality for airway management for patients with head-neck cancer undergoing surgery. This study aims to define factors predicting need of tracheostomy and define an effective objective criterion to predict tracheostomy need. 486 patients undergoing composite resections were studied. Factors analyzed were age, previous surgery, extent of surgery, trismus, extent of mandibular resection and reconstruction etc. Factors were divided into major and minor, using the clinical assessment scoring system for tracheostomy (CASST) criterion. Sixty seven (13.7%) patients required tracheostomy for their peri-operative management. Elective tracheostomies were done in 53 cases during surgery and post-operatively in 14 patients. All patients in whom tracheostomies were anticipated had a score of seven or more. A decision on whether or not an elective tracheotomy in head and neck surgery is necessary and can be facilitated using CASST criterion, which has a sensitivity of 95.5% and a negative predictive value (NPV) of 99.3%. It may reduce post-operative complications and contribute to safer treatment. Copyright © 2016 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  9. Emotional engagements predict and enhance social cognition in young chimpanzees.

    Science.gov (United States)

    Bard, Kim A; Bakeman, Roger; Boysen, Sarah T; Leavens, David A

    2014-09-01

    Social cognition in infancy is evident in coordinated triadic engagements, that is, infants attending jointly with social partners and objects. Current evolutionary theories of primate social cognition tend to highlight species differences in cognition based on human-unique cooperative motives. We consider a developmental model in which engagement experiences produce differential outcomes. We conducted a 10-year-long study in which two groups of laboratory-raised chimpanzee infants were given quantifiably different engagement experiences. Joint attention, cooperativeness, affect, and different levels of cognition were measured in 5- to 12-month-old chimpanzees, and compared to outcomes derived from a normative human database. We found that joint attention skills significantly improved across development for all infants, but by 12 months, the humans significantly surpassed the chimpanzees. We found that cooperativeness was stable in the humans, but by 12 months, the chimpanzee group given enriched engagement experiences significantly surpassed the humans. Past engagement experiences and concurrent affect were significant unique predictors of both joint attention and cooperativeness in 5- to 12-month-old chimpanzees. When engagement experiences and concurrent affect were statistically controlled, joint attention and cooperation were not associated. We explain differential social cognition outcomes in terms of the significant influences of previous engagement experiences and affect, in addition to cognition. Our study highlights developmental processes that underpin the emergence of social cognition in support of evolutionary continuity. © 2014 The Authors. Developmental Science Published by John Wiley & Sons Ltd.

  10. Appraisal and Reliability of Variable Engagement Model Prediction ...

    African Journals Online (AJOL)

    The variable engagement model based on the stress - crack opening displacement relationship and, which describes the behaviour of randomly oriented steel fibres composite subjected to uniaxial tension has been evaluated so as to determine the safety indices associated when the fibres are subjected to pullout and with ...

  11. Adults' future time perspective predicts engagement in physical activity.

    Science.gov (United States)

    Stahl, Sarah T; Patrick, Julie Hicks

    2012-07-01

    Our aim was to examine how the relations among known predictors of physical activity, such as age, sex, and body mass index, interact with future time perspective (FTP) and perceived functional limitation to explain adults' engagement in physical activity. Self-report data from 226 adults (range 20-88 years) were collected to examine the hypothesis that a more expansive FTP is associated with engagement in physical activity. Results indicated a good fit of the data to the model χ(2) (4, N = 226) = 7.457, p = .14 and accounted for a moderate amount of variance in adults' physical activity (R(2) = 15.7). Specifically, results indicated that perceived functional limitation (β = -.140) and FTP (β = .162) were directly associated with physical activity. Age was indirectly associated with physical activity through its association with perceived functional limitation (β = -.264) and FTP (β = .541). Results indicate that FTP may play an important role in explaining engagement in health promoting behaviors across the life span. Researchers should consider additional constructs and perhaps adopt socioemotional selectivity theory when explaining adults' engagement in physical activity.

  12. Predicted implications of using percentage weight gain as single discharge criterion in management of acute malnutrition in rural southern Ethiopia.

    Science.gov (United States)

    Forsén, Emmanuel; Tadesse, Elazar; Berhane, Yemane; Ekström, Eva-Charlotte

    2015-10-01

    Mid-upper arm circumference (MUAC) is increasingly used in identifying and admitting children with acute malnutrition for treatment. It is easy to use because it does not involve height assessment, but its use calls for alternative discharge criteria. This study examined how use of percentage weight gain as discharge criterion would affect the nutritional status of children admitted into a community-based management programme for acute malnutrition in rural southern Ethiopia. Non-oedematous children (n = 631) aged 6-59 months and having a MUAC of weight was added to admission weight and their nutritional status by weight-for-height z-score (WHZ) was determined at each target. Moderate and severe wasting according to World Health Organization WHZ definitions was used as outcome. Applying the most commonly recommended target of 15% weight gain resulted in 9% of children with admission MUAC weight gain was sufficient to generate a similar result. Children failing to recover were the ones with the poorest nutritional status at admission. Increasing the percentage weight gain targets in the two groups to 20% and 15%, respectively, would largely resolve wasting but likely lead to increased programme costs by keeping already recovered children in the programme. Further research is needed on appropriate discharge procedures in programmes using MUAC for screening and admission. © 2013 John Wiley & Sons Ltd.

  13. Social-class indicators differentially predict engagement in prevention vs. detection behaviours.

    Science.gov (United States)

    Haught, Heather M; Rose, Jason P; Brown, Jill A

    2016-01-01

    Few systematic studies have examined the contexts in which social-class variables will predict engagement in health-relevant behaviours. The current research examined whether the impact of social-class on health behaviours depends upon how social-class is assessed and the category of health behaviour under consideration. Our sample was drawn from the Health Information National Trends Survey in 2012 (N = 3959). Participants reported their income and education as well as their engagement in a variety of prevention and detection behaviours. Consistent with our hypothesised framework, we found that income predicted engagement in a variety of detection behaviours above and beyond education, whereas education predicted engagement in a variety of prevention behaviours above and beyond income. Our findings suggest that income and education operate on health behaviours via different pathways and have implications for public health policy and intervention.

  14. The Distributed Criterion Design

    Science.gov (United States)

    McDougall, Dennis

    2006-01-01

    This article describes and illustrates a novel form of the changing criterion design called the distributed criterion design, which represents perhaps the first advance in the changing criterion design in four decades. The distributed criterion design incorporates elements of the multiple baseline and A-B-A-B designs and is well suited to applied…

  15. Incremental Criterion Validity of the WJ-III COG Clinical Clusters: Marginal Predictive Effects beyond the General Factor

    Science.gov (United States)

    McGill, Ryan J.

    2015-01-01

    The current study examined the incremental validity of the clinical clusters from the Woodcock-Johnson III Tests of Cognitive Abilities (WJ-III COG) for predicting scores on the Woodcock-Johnson III Tests of Achievement (WJ-III ACH). All participants were children and adolescents (N = 4,722) drawn from the nationally representative WJ-III…

  16. Application of the strain energy for fatigue life prediction (LCF) of metals by the energy-based criterion

    International Nuclear Information System (INIS)

    Shahram Shahrooi; Ibrahim Henk Metselaar; Zainul Huda; Ghezavati, H.R.

    2009-01-01

    Full text: In this study, the plastic strain energy under multiaxial fatigue condition has been calculated in the cyclic plasticity models by the stress-strain hysteresis loops. Then, using the results of these models, the fatigue lives in energy-based fatigue model is predicted and compared to experimental data. Moreover, a weighting factor on shear plastic work is presented to decrease the life factors in the model fatigue. (author)

  17. Health Communication in Social Media: Message Features Predicting User Engagement on Diabetes-Related Facebook Pages.

    Science.gov (United States)

    Rus, Holly M; Cameron, Linda D

    2016-10-01

    Social media provides unprecedented opportunities for enhancing health communication and health care, including self-management of chronic conditions such as diabetes. Creating messages that engage users is critical for enhancing message impact and dissemination. This study analyzed health communications within ten diabetes-related Facebook pages to identify message features predictive of user engagement. The Common-Sense Model of Illness Self-Regulation and established health communication techniques guided content analyses of 500 Facebook posts. Each post was coded for message features predicted to engage users and numbers of likes, shares, and comments during the week following posting. Multi-level, negative binomial regressions revealed that specific features predicted different forms of engagement. Imagery emerged as a strong predictor; messages with images had higher rates of liking and sharing relative to messages without images. Diabetes consequence information and positive identity predicted higher sharing while negative affect, social support, and crowdsourcing predicted higher commenting. Negative affect, crowdsourcing, and use of external links predicted lower sharing while positive identity predicted lower commenting. The presence of imagery weakened or reversed the positive relationships of several message features with engagement. Diabetes control information and negative affect predicted more likes in text-only messages, but fewer likes when these messages included illustrative imagery. Similar patterns of imagery's attenuating effects emerged for the positive relationships of consequence information, control information, and positive identity with shares and for positive relationships of negative affect and social support with comments. These findings hold promise for guiding communication design in health-related social media.

  18. A Fisher’s Criterion-Based Linear Discriminant Analysis for Predicting the Critical Values of Coal and Gas Outbursts Using the Initial Gas Flow in a Borehole

    Directory of Open Access Journals (Sweden)

    Xiaowei Li

    2017-01-01

    Full Text Available The risk of coal and gas outbursts can be predicted using a method that is linear and continuous and based on the initial gas flow in the borehole (IGFB; this method is significantly superior to the traditional point prediction method. Acquiring accurate critical values is the key to ensuring accurate predictions. Based on ideal rock cross-cut coal uncovering model, the IGFB measurement device was developed. The present study measured the data of the initial gas flow over 3 min in a 1 m long borehole with a diameter of 42 mm in the laboratory. A total of 48 sets of data were obtained. These data were fuzzy and chaotic. Fisher’s discrimination method was able to transform these spatial data, which were multidimensional due to the factors influencing the IGFB, into a one-dimensional function and determine its critical value. Then, by processing the data into a normal distribution, the critical values of the outbursts were analyzed using linear discriminant analysis with Fisher’s criterion. The weak and strong outbursts had critical values of 36.63 L and 80.85 L, respectively, and the accuracy of the back-discriminant analysis for the weak and strong outbursts was 94.74% and 92.86%, respectively. Eight outburst tests were simulated in the laboratory, the reverse verification accuracy was 100%, and the accuracy of the critical value was verified.

  19. Gender differences in the factors predicting initial engagement at cardiac rehabilitation.

    Science.gov (United States)

    Galdas, Paul Michael; Harrison, Alexander Stephen; Doherty, Patrick

    2018-01-01

    To determine whether there are gender differences in the factors that predict attendance at the initial cardiac rehabilitation baseline assessment (CR engagement) after referral. Using data from the National Audit of Cardiac Rehabilitation, we analysed data on 95 638 patients referred to CR following a cardiovascular diagnosis/treatment between 2013 and 2016. Eighteen factors that have been shown in previous research to be important predictors of CR participation were investigated and grouped into four categories: sociodemographic factors, cardiac risk factors, patient medical status and service-level factors. Logistic binary regression models were built for male patients and female patients, assessing the likelihood for CR engagement. Each included predictors such as age, number of comorbidities and social deprivation score. There were no important differences in the factors that predict the likelihood of CR engagement in men and women. Seven factors associated with a reduced probability of CR engagement, and eight factors associated with increased probability, were identified. Fourteen of the 15 factors identified as predicting the likelihood for engagement/non-engagement were the same for both men and women. Increasing age, being South Asian or non-white ethnicity (other than Black) and being single were all associated with a reduced likelihood of attending an initial CR baseline assessment in both men and women. Male patients with diabetes were 11% less likely to engage with CR; however, there was no significant association in women. Results showed that the overwhelmingly important determinant of CR engagement observed in both men and women was receiving an invitation to attend an assessment session (OR 4.223 men/4.033women; pgender differences in predictors of CR uptake should probably be more nuanced and informed by the stage of the patient care pathway.

  20. "Engage" therapy: Prediction of change of late-life major depression.

    Science.gov (United States)

    Alexopoulos, George S; O'Neil, Robert; Banerjee, Samprit; Raue, Patrick J; Victoria, Lindsay W; Bress, Jennifer N; Pollari, Cristina; Arean, Patricia A

    2017-10-15

    Engage grew out of the need for streamlined psychotherapies that can be accurately used by community therapists in late-life depression. Engage was based on the view that dysfunction of reward networks is the principal mechanism mediating depressive symptoms. Accordingly, Engage uses "reward exposure" (exposure to meaningful activities) and assumes that repeated activation of reward networks will normalize these systems. This study examined whether change in a behavioral activation scale, an index of reward system function, predicts change in depressive symptomatology. The participants (N = 48) were older adults with major depression treated with 9 weekly sessions of Engage and assessed 27 weeks after treatment. Depression was assessed with the 24-item Hamilton Depression Rating Scale (HAM-D) and behavioral activation with the four subscales of Behavioral Activation for Depression Scale (activation, avoidance/rumination, work impairment, social impairment) at baseline, 6 weeks (mid-treatment), 9 weeks (end of treatment), and 36 weeks. Change only in the Activation subscale during successive periods of assessment predicted depression severity (HAM-D) at the end of each period (F 1, 47 = 21.05, psocial support. Change in behavioral activation predicts improvement of depressive symptoms and signs in depressed older adults treated with Engage. Copyright © 2017. Published by Elsevier B.V.

  1. Beyond Engagement Analytics: Which Online Mixed-Data Factors Predict Student Learning Outcomes?

    Science.gov (United States)

    Strang, Kenneth David

    2017-01-01

    This mixed-method study focuses on online learning analytics, a research area of importance. Several important student attributes and their online activities are examined to identify what seems to work best to predict higher grades. The purpose is to explore the relationships between student grade and key learning engagement factors using a large…

  2. Beyond size : Predicting engagement in environmental management practices of Dutch SMEs

    NARCIS (Netherlands)

    Uhlaner, L.M.; Berent-Braun, M.M.; Jeurissen, R.J.M.; Wit, de G.

    2012-01-01

    This study focuses on the prediction of the engagement of small- and medium-sized enterprises (SMEs) in environmental management practices, based on a random sample of 689 SMEs. The study finds that several endogenous factors, including tangibility of sector, firm size, innovative orientation,

  3. Does Self-Determination Predict the School Engagement of Four Different Motivation Types in Adolescence?

    Science.gov (United States)

    Raufelder, Diana; Regner, Nicola; Drury, Kate; Eid, Michael

    2016-01-01

    In order to enhance our understanding of inter-individual differences in scholastic motivation, this study examined if self-determination predicts the school engagement of four different motivation types (MT) in a large sample of adolescent students (N = 1088) from Brandenburg, Germany: (1) peer-dependent MT, (2) teacher-dependent MT, (3)…

  4. The Interplay of Maternal Sensitivity and Toddler Engagement of Mother in Predicting Self-Regulation

    Science.gov (United States)

    Ispa, Jean M.; Su-Russell, Chang; Palermo, Francisco; Carlo, Gustavo

    2017-01-01

    Using data from the Early Head Start Research and Evaluation Project, a cross-lag mediation model was tested to examine longitudinal relations among low-income mothers' sensitivity; toddlers' engagement of their mothers; and toddler's self-regulation at ages 1, 2, and 3 years (N = 2,958). Age 1 maternal sensitivity predicted self-regulation at…

  5. Do workaholism and work engagement predict employee well-being and performance in opposite directions?

    Science.gov (United States)

    Shimazu, Akihito; Schaufeli, Wilmar B; Kubota, Kazumi; Kawakami, Norito

    2012-01-01

    This study investigated the distinctiveness between workaholism and work engagement by examining their longitudinal relationships (measurement interval=7 months) with well-being and performance in a sample of 1,967 Japanese employees from various occupations. Based on a previous cross-sectional study (Shimazu & Schaufeli, 2009), we expected that workaholism predicts future unwell-being (i.e., high ill-health and low life satisfaction) and poor job performance, whereas work engagement predicts future well-being (i.e., low ill-health and high life satisfaction) and superior job performance. T1-T2 changes in ill-health, life satisfaction and job performance were measured as residual scores that were then included in the structural equation model. Results showed that workaholism and work engagement were weakly and positively related to each other. In addition, workaholism was related to an increase in ill-health and to a decrease in life satisfaction. In contrast, work engagement was related to a decrease in ill-health and to increases in both life satisfaction and job performance. These findings suggest that workaholism and work engagement are two different kinds of concepts that are oppositely related to well-being and performance.

  6. Social interaction anxiety and personality traits predicting engagement in health risk sexual behaviors.

    Science.gov (United States)

    Rahm-Knigge, Ryan L; Prince, Mark A; Conner, Bradley T

    2018-06-01

    Individuals with social interaction anxiety, a facet of social anxiety disorder, withdraw from or avoid social encounters and generally avoid risks. However, a subset engages in health risk sexual behavior (HRSB). Because sensation seeking, emotion dysregulation, and impulsivity predict engagement in HRSB among adolescents and young adults, the present study hypothesized that latent classes of social interaction anxiety and these personality traits would differentially predict likelihood of engagement in HRSB. Finite mixture modeling was used to discern four classes: two low social interaction anxiety classes distinguished by facets of emotion dysregulation, positive urgency, and negative urgency (Low SIAS High Urgency and Low SIAS Low Urgency) and two high social interaction anxiety classes distinguished by positive urgency, negative urgency, risk seeking, and facets of emotion dysregulation (High SIAS High Urgency and High SIAS Low Urgency). HRSB were entered into the model as auxiliary distal outcomes. Of importance to this study were findings that the High SIAS High Urgency class was more likely to engage in most identified HRSB than the High SIAS Low Urgency class. This study extends previous findings on the heterogeneity of social interaction anxiety by identifying the effects of social interaction anxiety and personality on engagement in HRSB. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. The Brand's PREACH Model: Predicting Readiness to Engage African American Churches in Health.

    Science.gov (United States)

    Brand, Dorine J; Alston, Reginald J

    2017-09-01

    Despite many attempts to reduce health disparities, health professionals face obstacles in improving poor health outcomes within the African American (AA) community. To promote change for improved health measures, it is important to implement culturally tailored programming through a trusted institution, such as the AA church. While churches have the potential to play an important role in positively impacting health among AAs, it is unclear what attributes are necessary to predict success or failure for health promotion within these institutions. The purpose of this study was to create a model, the Brand's PREACH ( Predicting Readiness to Engage African American Churches in Health) Model, to predict the readiness of AA churches to engage in health promotion programming. Thirty-six semistructured key informant interviews were conducted with 12 pastors, 12 health leaders, and 12 congregants to gain information on the relationship between church infrastructure (physical structure, personnel, funding, and social/cultural support), readiness, and health promotion programming. The findings revealed that church infrastructure has an association with and will predict the readiness of a church to engage in health promotion programming. The ability to identify readiness early on will be useful for developing, implementing, and evaluating faith-based interventions, in partnership with churches, which is a key factor for sustainable and effective programs.

  8. Stigma Predicts Treatment Preferences and Care Engagement among Veterans Affairs Primary Care Patients with Depression

    Science.gov (United States)

    Campbell, Duncan G.; Bonner, Laura M.; Bolkan, Cory R.; Lanto, Andrew B.; Zivin, Kara; Waltz, Thomas J.; Klap, Ruth; Rubenstein, Lisa V.; Chaney, Edmund F.

    2016-01-01

    Background Whereas stigma regarding mental health concerns exists, the evidence for stigma as a depression treatment barrier among patients in Veterans Affairs (VA) primary care (PC) is mixed. Purpose To test whether stigma, defined as depression label avoidance, predicted patients' preferences for depression treatment providers, patients' prospective engagement in depression care, and care quality. Methods We conducted cross-sectional and prospective analyses of existing data from 761 VA PC patients with probable major depression. Results Relative to low stigma patients, those with high stigma were less likely to prefer treatment from mental health specialists. In prospective controlled analyses, high stigma predicted lower likelihood of the following: taking medications for mood, treatment by mental health specialists, treatment for emotional concerns in PC, and appropriate depression care. Conclusions High stigma is associated with lower preferences for care from mental health specialists and confers risk for minimal depression treatment engagement. PMID:26935310

  9. On the Jeans criterion

    International Nuclear Information System (INIS)

    Whitworth, A.P.

    1980-01-01

    The Jeans criterion is first stated and distinguished from the Virial Theorem. Then it is discussed how the Jeans criterion can be derived from the Virial Theorem and the inherent shortcomings in this derivation. Finally, it is indicated how these shortcomings might be overcome. The Jeans criterion is a fragmentation - or condensation -criterion. An expression is given, connecting the fragmentation of an unstable extended medium into masses Msub(J). Rather than picturing the background medium fragmenting, it is probably more appropriate to envisage these masses Msub(J) 'condensing' out of the background medium. On the condensation picture some fraction of the background material separates out into coherent bound nodules under the pull of its self-gravity. For this reason the Jeans criterion is discussed as a condensation condition, reserving the term fragmentation for a different process. The Virial Theorem provides a contraction criterion. This is described with reference to a spherical cloud and is developed to derive the Jeans criterion. (U.K.)

  10. Predicting drive for muscularity behavioural engagement from body image attitudes and emotions.

    Science.gov (United States)

    Tod, David; Edwards, Christian

    2013-01-01

    We examined the potential moderating effects of appearance investment, body image disturbance, and situational body image dysphoria on the drive for muscularity attitude-behaviour relationship. Participants (339 British college men, M(AGE)=20.00 years, SD=2.59) completed drive for muscularity attitude and behaviour, appearance investment, body image disturbance, and situational body image dysphoria measures. Results indicated higher levels of appearance investment, body image disturbance, and situational body image dysphoria were associated with increases in the drive for muscularity attitude's relationship with physique-enhancing behavioural engagement. Results help extend recent research that has moved beyond identifying correlates to examining ways that groups of variables interact to predict drive for muscularity behavioural engagement and may contribute to theory development. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Attachment and personality predicts engagement in sexual harassment by male and female college students.

    Science.gov (United States)

    Mènard, Kim S; Shoss, Naomi E; Pincus, Aaron L

    2010-01-01

    The purpose of this study was to examine a trait model of personality (Five-Factor Model) as a mediator of the relationship between attachment styles and sexually harassing behavior in a sample of male (N = 148) and female (N = 278) college students. We found that gender (male) and low Agreeableness predicted engaging in sexual harassment and all three of its subtypes; gender harassment, unwanted sexual attention, and sexual coercion. Further, low Conscientiousness predicted overall sexual harassment, gender harassment, and unwanted sexual attention. Personality traits mediated the relationship between insecure attachment styles (Preoccupation with Relationships and Relationships as Secondary) and sexually harassing behaviors. Thus, factors beyond gender can help predict students' propensity to sexually harass others.

  12. Psychosocial assessments for young people: a systematic review examining acceptability, disclosure and engagement, and predictive utility

    Directory of Open Access Journals (Sweden)

    Bradford S

    2012-12-01

    Full Text Available Sally Bradford,1 Debra Rickwood1,21Faculty of Health, University of Canberra, Canberra, 2Headspace National Youth Mental Health Foundation, North Melbourne, AustraliaAbstract: Adolescence and young adulthood are often turbulent periods in a person’s life. There are high rates of accidental deaths, suicide, mental health concerns, substance use, and sexual experimentation. Health care professionals need to conduct holistic assessments of clients in these developmental life stages to identify psychosocial risks and provide targeted early intervention and implement prevention strategies. The most useful psychosocial assessments for most health care professionals are those that can provide a complete picture of the young person’s life and circumstances. This article identifies psychosocial assessment instruments that can be used as an initial assessment and engagement tool with the general population of young people presenting for health care. We review the psychometric properties of each of the instruments, determining what type of instrument is most acceptable to young people, whether any can increase disclosure and improve engagement between young people and health professionals, and whether they have predictive utility. The search strategy complied with the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA statement. A total of 89 published articles were identified, covering 31 different assessment instruments. Results indicated that those that were self-administered were most acceptable to young people, although it is unclear whether pen-and-paper or computer formats were preferred. Most psychosocial assessments can improve rates of disclosure and enhance engagement between young people and health professionals; however, worryingly, we found evidence that clinicians did not always respond to some of the most serious identified risks. Only for one instrument was there any mention of

  13. Latent profiles of nonresidential father engagement six years after divorce predict long-term offspring outcomes.

    Science.gov (United States)

    Modecki, Kathryn Lynn; Hagan, Melissa J; Sandler, Irwin; Wolchik, Sharlene A

    2015-01-01

    This study examined profiles of nonresidential father engagement (i.e., support to the adolescent, contact frequency, remarriage, relocation, and interparental conflict) with their adolescent children (N = 156) 6 to 8 years following divorce and the prospective relation between these profiles and the psychosocial functioning of their offspring, 9 years later. Parental divorce occurred during late childhood to early adolescence; indicators of nonresidential father engagement were assessed during adolescence, and mental health problems and academic achievement of offspring were assessed 9 years later in young adulthood. Three profiles of father engagement were identified in our sample of mainly White, non-Hispanic divorced fathers: Moderate Involvement/Low Conflict, Low Involvement/Moderate Conflict, and High Involvement/High Conflict. Profiles differentially predicted offspring outcomes 9 years later when they were young adults, controlling for quality of the mother-adolescent relationship, mother's remarriage, mother's income, and gender, age, and offspring mental health problems in adolescence. Offspring of fathers characterized as Moderate Involvement/Low Conflict had the highest academic achievement and the lowest number of externalizing problems 9 years later compared to offspring whose fathers had profiles indicating either the highest or lowest levels of involvement but higher levels of conflict. Results indicate that greater paternal psychosocial support and more frequent father-adolescent contact do not outweigh the negative impact of interparental conflict on youth outcomes in the long term. Implications of findings for policy and intervention are discussed.

  14. Fuel-pin cladding transient failure strain criterion

    International Nuclear Information System (INIS)

    Bard, F.E.; Duncan, D.R.; Hunter, C.W.

    1983-01-01

    A criterion for cladding failure based on accumulated strain was developed for mixed uranium-plutonium oxide fuel pins and used to interpret the calculated strain results from failed transient fuel pin experiments conducted in the Transient Reactor Test (TREAT) facility. The new STRAIN criterion replaced a stress-based criterion that depends on the DORN parameter and that incorrectly predicted fuel pin failure for transient tested fuel pins. This paper describes the STRAIN criterion and compares its prediction with those of the stress-based criterion

  15. Future Time Orientation Predicts Academic Engagement among First-Year University Students

    Science.gov (United States)

    Horstmanshof, Louise; Zimitat, Craig

    2007-01-01

    Background: Enhancing student engagement is considered an important strategy for improving retention. Students' Time Perspective is an under-researched factor that may significantly influence student engagement. Aims: This study examines interrelationships between elements of student engagement and relationship with Time Perspective. We propose…

  16. General Criterion for Harmonicity

    Science.gov (United States)

    Proesmans, Karel; Vandebroek, Hans; Van den Broeck, Christian

    2017-10-01

    Inspired by Kubo-Anderson Markov processes, we introduce a new class of transfer matrices whose largest eigenvalue is determined by a simple explicit algebraic equation. Applications include the free energy calculation for various equilibrium systems and a general criterion for perfect harmonicity, i.e., a free energy that is exactly quadratic in the external field. As an illustration, we construct a "perfect spring," namely, a polymer with non-Gaussian, exponentially distributed subunits which, nevertheless, remains harmonic until it is fully stretched. This surprising discovery is confirmed by Monte Carlo and Langevin simulations.

  17. Absorbed in the task : Personality measures predict engagement during task performance as tracked by error negativity and asymmetrical frontal activity

    NARCIS (Netherlands)

    Tops, Mattie; Boksem, Maarten A. S.

    2010-01-01

    We hypothesized that interactions between traits and context predict task engagement, as measured by the amplitude of the error-related negativity (ERN), performance, and relative frontal activity asymmetry (RFA). In Study 1, we found that drive for reward, absorption, and constraint independently

  18. Unified Bohm criterion

    Energy Technology Data Exchange (ETDEWEB)

    Kos, L. [LECAD Laboratory, Faculty of Mechanical Engineering, University of Ljubljana, SI-1000 Ljubljana (Slovenia); Tskhakaya, D. D.; Jelić, N. [Institute for Theoretical Physics, Fusion@ÖAW, University of Innsbruck, A-6020 Innsbruck (Austria)

    2015-09-15

    Recent decades have seen research into the conditions necessary for the formation of the monotonic potential shape in the sheath, appearing at the plasma boundaries like walls, in fluid, and kinetic approximations separately. Although either of these approaches yields a formulation commonly known as the much-acclaimed Bohm criterion (BC), the respective results involve essentially different physical quantities that describe the ion gas behavior. In the fluid approach, such a quantity is clearly identified as the ion directional velocity. In the kinetic approach, the ion behavior is formulated via a quantity (the squared inverse velocity averaged by the ion distribution function) without any clear physical significance, which is, moreover, impractical. In the present paper, we try to explain this difference by deriving a condition called here the Unified Bohm Criterion, which combines an advanced fluid model with an upgraded explicit kinetic formula in a new form of the BC. By introducing a generalized polytropic coefficient function, the unified BC can be interpreted in a form that holds, irrespective of whether the ions are described kinetically or in the fluid approximation.

  19. Job demands-resources predicting burnout and work engagement among Belgian home health care nurses: A cross-sectional study.

    Science.gov (United States)

    Vander Elst, Tinne; Cavents, Carolien; Daneels, Katrien; Johannik, Kristien; Baillien, Elfi; Van den Broeck, Anja; Godderis, Lode

    A better knowledge of the job aspects that may predict home health care nurses' burnout and work engagement is important in view of stress prevention and health promotion. The Job Demands-Resources model predicts that job demands and resources relate to burnout and work engagement but has not previously been tested in the specific context of home health care nursing. The present study offers a comprehensive test of the Job-Demands Resources model in home health care nursing. We investigate the main and interaction effects of distinctive job demands (workload, emotional demands and aggression) and resources (autonomy, social support and learning opportunities) on burnout and work engagement. Analyses were conducted using cross-sectional data from 675 Belgian home health care nurses, who participated in a voluntary and anonymous survey. The results show that workload and emotional demands were positively associated with burnout, whereas aggression was unrelated to burnout. All job resources were associated with higher levels of work engagement and lower levels of burnout. In addition, social support buffered the positive relationship between workload and burnout. Home health care organizations should invest in dealing with workload and emotional demands and stimulating the job resources under study to reduce the risk of burnout and increase their nurses' work engagement. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. The Cost of Materialism in a Collectivistic Culture: Predicting Risky Behavior Engagement in Chinese Adolescents

    Science.gov (United States)

    Auerbach, Randy P.; McWhinnie, Chad M.; Goldfinger, Marc; Abela, John R. Z.; Zhu, Xiongzhao; Yao, Shuqiao

    2010-01-01

    The goals of the current study were to examine whether (a) negative events mediate the relationship between materialism and risky behavior engagement and (b) materialism moderates the relationship between stress and engagement in risky behaviors in Chinese youth. At Time 1, 406 adolescents (ages 14-19) from Yue Yang, China, completed measures…

  1. How personal resources predict work engagement and self-rated performance among construction workers: a social cognitive perspective.

    Science.gov (United States)

    Lorente, Laura; Salanova, Marisa; Martínez, Isabel M; Vera, María

    2014-06-01

    Traditionally, research focussing on psychosocial factors in the construction industry has focused mainly on the negative aspects of health and on results such as occupational accidents. This study, however, focuses on the specific relationships among the different positive psychosocial factors shared by construction workers that could be responsible for occupational well-being and outcomes such as performance. The main objective of this study was to test whether personal resources predict self-rated job performance through job resources and work engagement. Following the predictions of Bandura's Social Cognitive Theory and the motivational process of the Job Demands-Resources Model, we expect that the relationship between personal resources and performance will be fully mediated by job resources and work engagement. The sample consists of 228 construction workers. Structural equation modelling supports the research model. Personal resources (i.e. self-efficacy, mental and emotional competences) play a predicting role in the perception of job resources (i.e. job control and supervisor social support), which in turn leads to work engagement and self-rated performance. This study emphasises the crucial role that personal resources play in determining how people perceive job resources by determining the levels of work engagement and, hence, their self-rated job performance. Theoretical and practical implications are discussed. © 2014 International Union of Psychological Science.

  2. A comparative study on the forming limit diagram prediction between Marciniak-Kuczynski model and modified maximum force criterion by using the evolving non-associated Hill48 plasticity model

    Science.gov (United States)

    Shen, Fuhui; Lian, Junhe; Münstermann, Sebastian

    2018-05-01

    Experimental and numerical investigations on the forming limit diagram (FLD) of a ferritic stainless steel were performed in this study. The FLD of this material was obtained by Nakajima tests. Both the Marciniak-Kuczynski (MK) model and the modified maximum force criterion (MMFC) were used for the theoretical prediction of the FLD. From the results of uniaxial tensile tests along different loading directions with respect to the rolling direction, strong anisotropic plastic behaviour was observed in the investigated steel. A recently proposed anisotropic evolving non-associated Hill48 (enHill48) plasticity model, which was developed from the conventional Hill48 model based on the non-associated flow rule with evolving anisotropic parameters, was adopted to describe the anisotropic hardening behaviour of the investigated material. In the previous study, the model was coupled with the MMFC for FLD prediction. In the current study, the enHill48 was further coupled with the MK model. By comparing the predicted forming limit curves with the experimental results, the influences of anisotropy in terms of flow rule and evolving features on the forming limit prediction were revealed and analysed. In addition, the forming limit predictive performances of the MK and the MMFC models in conjunction with the enHill48 plasticity model were compared and evaluated.

  3. Do burnout and work engagement predict depressive symptoms and life satisfaction? A three-wave seven-year prospective study.

    Science.gov (United States)

    Hakanen, Jari J; Schaufeli, Wilmar B

    2012-12-10

    Burnout and work engagement have been viewed as opposite, yet distinct states of employee well-being. We investigated whether work-related indicators of well-being (i.e. burnout and work engagement) spill-over and generalize to context-free well-being (i.e. depressive symptoms and life satisfaction). More specifically, we examined the causal direction: does burnout/work engagement lead to depressive symptoms/life satisfaction, or the other way around? Three surveys were conducted. In 2003, 71% of all Finnish dentists were surveyed (n=3255), and the response rate of the 3-year follow-up was 84% (n=2555). The second follow-up was conducted four years later with a response rate of 86% (n=1964). Structural equation modeling was used to investigate the cross-lagged associations between the study variables across time. Burnout predicted depressive symptoms and life dissatisfaction from T1 to T2 and from T2 to T3. Conversely, work engagement had a negative effect on depressive symptoms and a positive effect on life satisfaction, both from T1 to T2 and from T2 to T3, even after adjusting for the impact of burnout at every occasion. The study was conducted among one occupational group, which limits its generalizability. Work-related well-being predicts general wellbeing in the long-term. For example, burnout predicts depressive symptoms and not vice versa. In addition, burnout and work engagement are not direct opposites. Instead, both have unique, incremental impacts on life satisfaction and depressive symptoms. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. When does spiritual intelligence particularly predict job engagement? The mediating role of psychological empowerment

    OpenAIRE

    Mohsen Torabi; Iman Zohoorian Nadali

    2016-01-01

    Background: Regarding the importance of health care providers such as nurses who are always in stressful environments, it is imperative to better understand how they become more engaged in their work. The purpose of this paper is to focus on health care providers (nurses), and examine how the interaction between spiritual intelligence and psychological empowerment affect job engagement. Materials and Methods: This descriptive and quantitative study was conducted among nurses at the Faghihi Ho...

  5. When does spiritual intelligence particularly predict job engagement? The mediating role of psychological empowerment.

    Science.gov (United States)

    Torabi, Mohsen; Nadali, Iman Zohoorian

    2016-01-01

    Regarding the importance of health care providers such as nurses who are always in stressful environments, it is imperative to better understand how they become more engaged in their work. The purpose of this paper is to focus on health care providers (nurses), and examine how the interaction between spiritual intelligence and psychological empowerment affect job engagement. This descriptive and quantitative study was conducted among nurses at the Faghihi Hospital in Shiraz, Iran in 2010. A sample of nurses ( n = 179) completed standard survey questionnaire including spiritual intelligence, psychological empowerment, and job engagement which included 5 questions for each dimensions. For testing the hypotheses of the study, results were analyzed through structural equation modeling (SEM) using LISREL 8.8. SEM revealed that psychological empowerment could fully mediate the relationship between spiritual intelligence and job engagement. However, the correlation between spiritual intelligence and job engagement was significant but weak using Pearson coefficient method. This can imply that psychological empowerment plays a crucial role in the relationship between spiritual intelligence and job engagement. This paper indicates that spiritual intelligence might affect different organizational parameters, directly or indirectly. Therefore, it is recommended that the researchers evaluate probable relationships between spiritual intelligence and other variables.

  6. Understanding motivational structures that differentially predict engagement and achievement in middle school science

    Science.gov (United States)

    Lee, Christine S.; Hayes, Kathryn N.; Seitz, Jeffery; DiStefano, Rachelle; O'Connor, Dawn

    2016-01-01

    Middle school has been documented as the period in which a drop in students' science interest and achievement occurs. This trend indicates a lack of motivation for learning science; however, little is known about how different aspects of motivation interact with student engagement and science learning outcomes. This study examines the relationships among motivational factors, engagement, and achievement in middle school science (grades 6-8). Data were obtained from middle school students in the United States (N = 2094). The theoretical relationships among motivational constructs, including self-efficacy, and three types of goal orientations (mastery, performance approach, and performance avoid) were tested. The results showed that motivation is best modeled as distinct intrinsic and extrinsic factors; lending evidence that external, performance based goal orientations factor separately from self-efficacy and an internal, mastery based goal orientation. Second, a model was tested to examine how engagement mediated the relationships between intrinsic and extrinsic motivational factors and science achievement. Engagement mediated the relationship between intrinsic motivation and science achievement, whereas extrinsic motivation had no relationship with engagement and science achievement. Implications for how classroom practice and educational policy emphasize different student motivations, and in turn, can support or hinder students' science learning are discussed.

  7. Pro B-type natriuretic peptide plasma value: a new criterion for the prediction of short- and long-term outcomes after transcatheter aortic valve implantation.

    Science.gov (United States)

    López-Otero, Diego; Trillo-Nouche, Ramiro; Gude, Francisco; Cid-Álvarez, Belen; Ocaranza-Sanchez, Raimundo; Alvarez, Melisa Santas; Lear, Pamela V; Gonzalez-Juanatey, José R

    2013-09-30

    To determine the prognostic value of pro B-type natriuretic peptide (pro-BNP) to predict mortality after transcatheter aortic valve implantation (TAVI). Logistic EuroSCORE (LES) overestimates observed mortality after TAVI. A new risk score specific to TAVI is needed to accurately assess mortality and outcome. Eighty-five patients were included. Indications for TAVI were nonoperable or surgically high-risk patients (LES>20%). Pro-BNP was measured 24h before the procedure. Cox proportional hazards model was used to evaluate clinical factors. The predictive accuracy of these Cox models was determined by using time-dependent receiver operating characteristic (ROC) curves. Pro-BNP levels (log-transformed) were significantly higher in non-survivors than in survivors at 30 days (3.36 ± 0.43 vs. 3.81 ± 0.43, p<0.004) and at the end of follow-up (3.34 ± 0.42 vs. 3.63 ± 0.48, p<0.011). Multivariate analysis revealed that only increased log pro-BNP levels were associated with higher mortality rate at short [hazard ratio (HR) (95% confidence intervals (CI)]=5.35 (1.74-16.5), p=0.003] and long-term follow-ups [HR=11 (CI: 1.51-81.3), p=0.018]. LES was not associated with increased mortality at either time point [HR=1.03 (CI: 0.95-1.10), p=0.483 and HR=1.03 (CI: 0.98-1.07), p=0.230, respectively]. At 30, 90, 180, and 365 days, the c-index was 0.72 for log pro-BNP and 0.63 for LES (p=0.044). Pre-procedure log transform of plasma pro-BNP levels are an independent and strong predictor of short- and long-term outcomes after TAVI and are more discriminatory than LES. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  8. Take care of well-being: how facilitators and engagement predict performance of university students

    Directory of Open Access Journals (Sweden)

    Isabel M. Martínez

    2016-03-01

    Full Text Available The interest in developing a high quality educational system requires constant research of the variables involved in the teaching-learning process. Among these variables, social and academic facilitators are important because there is empirical evidence about their positive relationship with engagement, commitment, self-efficacy, happiness and satisfaction in the academic context. Moreover, the psychological well-being of university students (i.e., engagement showed to positively affect future academic success. In line, the aim of this study is twofold. First, the relevance of social and university academic facilitators was analyzed depending on the faculty of belonging. Second, the effect of social (e.g., Good relationship with classmates and academic facilitators (e.g., Updated website with new information and easily accessible as well as academic engagement on academic performance (i.e., GPA was tested. The sample consisted of 965 University students. The ANOVAs’ results showed the existence of statistically significant differences in social and university academic facilitators among the different faculties.  Regression analyses demonstrated that social (but not university’s facilitators and academic engagement were positively related to academic performance. Additionally, the interaction between social facilitators and academic engagement was positively related to academic performance.  The effect was also significant when controlling for gender and faculty. The identification of different facilitators allows to develop different activities depending on the faculty, as well as leading to the optimization of teaching-learning process. Moreover, academic facilitators do not affect academic performance. From a practical view, it means that specific interventions can be implemented during the course so that students’ social facilitators and engagement increase.

  9. Protection motivation theory in predicting intention to engage in protective behaviors against schistosomiasis among middle school students in rural China.

    Science.gov (United States)

    Xiao, Han; Li, Shiyue; Chen, Xinguang; Yu, Bin; Gao, Mengting; Yan, Hong; Okafor, Chukwuemeka N

    2014-10-01

    Among millions of people who suffer from schistosomiasis in China, adolescents are at increased risk to be infected. However, there is a lack of theory-guided behavioral prevention intervention programs to protect these adolescents. This study attempted to apply the Protection Motivation Theory (PMT) in predicting intentions to engage in protective behaviors against schistosomiasis infection. The participants were selected using the stratified cluster sampling method. Survey data were collected using anonymous self-reported questionnaire. The advanced structural equation modeling (SEM) method was utilized to assess the complex relationship among schistosomiasis knowledge, previous risk exposure and protective measures in predicting intentions to engage in protective behavior through the PMT constructs. Approximately 70% of participants reported they were always aware of schistosomiasis before exposure to water with endemic schistosomiasis, 6% of the participants reported frequency of weekly or monthly prior exposure to snail-conditioned water. 74% of participants reported having always engaged in protective behaviors in the past three months. Approximately 7% were unlikely or very unlikely to avoid contact with snail-conditioned water, and to use protective behaviors before exposure. Results from SEM analysis indicated that both schistosomiasis knowledge and prior exposure to schistosomiasis were indirectly related to behavior intentions through intrinsic rewards and self-efficacy; prior protective behaviors were indirectly related to behavior intentions through severity, intrinsic rewards and self-efficacy, while awareness had an indirect relationship with behavior intentions through self-efficacy. Among the seven PMT constructs, severity, intrinsic rewards and self-efficacy were significantly associated with behavior intentions. The PMT can be used to predict the intention to engage in protective behaviors against schistosomiasis. Schistosomiasis intervention

  10. Protection Motivation Theory in Predicting Intention to Engage in Protective Behaviors against Schistosomiasis among Middle School Students in Rural China

    Science.gov (United States)

    Chen, Xinguang; Yu, Bin; Gao, Mengting; Yan, Hong; Okafor, Chukwuemeka N.

    2014-01-01

    Background Among millions of people who suffer from schistosomiasis in China, adolescents are at increased risk to be infected. However, there is a lack of theory-guided behavioral prevention intervention programs to protect these adolescents. This study attempted to apply the Protection Motivation Theory (PMT) in predicting intentions to engage in protective behaviors against schistosomiasis infection. Methods The participants were selected using the stratified cluster sampling method. Survey data were collected using anonymous self-reported questionnaire. The advanced structural equation modeling (SEM) method was utilized to assess the complex relationship among schistosomiasis knowledge, previous risk exposure and protective measures in predicting intentions to engage in protective behavior through the PMT constructs. Principal Findings Approximately 70% of participants reported they were always aware of schistosomiasis before exposure to water with endemic schistosomiasis, 6% of the participants reported frequency of weekly or monthly prior exposure to snail-conditioned water. 74% of participants reported having always engaged in protective behaviors in the past three months. Approximately 7% were unlikely or very unlikely to avoid contact with snail-conditioned water, and to use protective behaviors before exposure. Results from SEM analysis indicated that both schistosomiasis knowledge and prior exposure to schistosomiasis were indirectly related to behavior intentions through intrinsic rewards and self-efficacy; prior protective behaviors were indirectly related to behavior intentions through severity, intrinsic rewards and self-efficacy, while awareness had an indirect relationship with behavior intentions through self-efficacy. Among the seven PMT constructs, severity, intrinsic rewards and self-efficacy were significantly associated with behavior intentions. Conclusions The PMT can be used to predict the intention to engage in protective behaviors against

  11. Protection motivation theory in predicting intention to engage in protective behaviors against schistosomiasis among middle school students in rural China.

    Directory of Open Access Journals (Sweden)

    Han Xiao

    2014-10-01

    Full Text Available Among millions of people who suffer from schistosomiasis in China, adolescents are at increased risk to be infected. However, there is a lack of theory-guided behavioral prevention intervention programs to protect these adolescents. This study attempted to apply the Protection Motivation Theory (PMT in predicting intentions to engage in protective behaviors against schistosomiasis infection.The participants were selected using the stratified cluster sampling method. Survey data were collected using anonymous self-reported questionnaire. The advanced structural equation modeling (SEM method was utilized to assess the complex relationship among schistosomiasis knowledge, previous risk exposure and protective measures in predicting intentions to engage in protective behavior through the PMT constructs.Approximately 70% of participants reported they were always aware of schistosomiasis before exposure to water with endemic schistosomiasis, 6% of the participants reported frequency of weekly or monthly prior exposure to snail-conditioned water. 74% of participants reported having always engaged in protective behaviors in the past three months. Approximately 7% were unlikely or very unlikely to avoid contact with snail-conditioned water, and to use protective behaviors before exposure. Results from SEM analysis indicated that both schistosomiasis knowledge and prior exposure to schistosomiasis were indirectly related to behavior intentions through intrinsic rewards and self-efficacy; prior protective behaviors were indirectly related to behavior intentions through severity, intrinsic rewards and self-efficacy, while awareness had an indirect relationship with behavior intentions through self-efficacy. Among the seven PMT constructs, severity, intrinsic rewards and self-efficacy were significantly associated with behavior intentions.The PMT can be used to predict the intention to engage in protective behaviors against schistosomiasis. Schistosomiasis

  12. Harnessing Facebook for Smoking Reduction and Cessation Interventions: Facebook User Engagement and Social Support Predict Smoking Reduction.

    Science.gov (United States)

    Kim, Sunny Jung; Marsch, Lisa A; Brunette, Mary F; Dallery, Jesse

    2017-05-23

    Social media technologies offer a novel opportunity for scalable health interventions that can facilitate user engagement and social support, which in turn may reinforce positive processes for behavior change. By using principles from health communication and social support literature, we implemented a Facebook group-based intervention that targeted smoking reduction and cessation. This study hypothesized that participants' engagement with and perceived social support from our Facebook group intervention would predict smoking reduction. We recruited 16 regular smokers who live in the United States and who were motivated in quitting smoking at screening. We promoted message exposure as well as engagement and social support systems throughout the intervention. For message exposure, we posted prevalidated, antismoking messages (such as national antismoking campaigns) on our smoking reduction and cessation Facebook group. For engagement and social support systems, we delivered a high degree of engagement and social support systems during the second and third week of the intervention and a low degree of engagement and social support systems during the first and fourth week. A total of six surveys were conducted via Amazon Mechanical Turk (MTurk) at baseline on a weekly basis and at a 2-week follow-up. Of the total 16 participants, most were female (n=13, 81%), white (n=15, 94%), and between 25 and 50 years of age (mean 34.75, SD 8.15). There was no study attrition throughout the 6-time-point baseline, weekly, and follow-up surveys. We generated Facebook engagement and social support composite scores (mean 19.19, SD 24.35) by combining the number of likes each participant received and the number of comments or wall posts each participant posted on our smoking reduction and cessation Facebook group during the intervention period. The primary outcome was smoking reduction in the past 7 days measured at baseline and at the two-week follow-up. Compared with the baseline

  13. Harnessing Facebook for Smoking Reduction and Cessation Interventions: Facebook User Engagement and Social Support Predict Smoking Reduction

    Science.gov (United States)

    Marsch, Lisa A; Brunette, Mary F; Dallery, Jesse

    2017-01-01

    Background Social media technologies offer a novel opportunity for scalable health interventions that can facilitate user engagement and social support, which in turn may reinforce positive processes for behavior change. Objective By using principles from health communication and social support literature, we implemented a Facebook group–based intervention that targeted smoking reduction and cessation. This study hypothesized that participants’ engagement with and perceived social support from our Facebook group intervention would predict smoking reduction. Methods We recruited 16 regular smokers who live in the United States and who were motivated in quitting smoking at screening. We promoted message exposure as well as engagement and social support systems throughout the intervention. For message exposure, we posted prevalidated, antismoking messages (such as national antismoking campaigns) on our smoking reduction and cessation Facebook group. For engagement and social support systems, we delivered a high degree of engagement and social support systems during the second and third week of the intervention and a low degree of engagement and social support systems during the first and fourth week. A total of six surveys were conducted via Amazon Mechanical Turk (MTurk) at baseline on a weekly basis and at a 2-week follow-up. Results Of the total 16 participants, most were female (n=13, 81%), white (n=15, 94%), and between 25 and 50 years of age (mean 34.75, SD 8.15). There was no study attrition throughout the 6-time-point baseline, weekly, and follow-up surveys. We generated Facebook engagement and social support composite scores (mean 19.19, SD 24.35) by combining the number of likes each participant received and the number of comments or wall posts each participant posted on our smoking reduction and cessation Facebook group during the intervention period. The primary outcome was smoking reduction in the past 7 days measured at baseline and at the two

  14. A mixed methods exploration of the team and organizational factors that may predict new graduate nurse engagement in collaborative practice.

    Science.gov (United States)

    Pfaff, Kathryn A; Baxter, Pamela E; Ploeg, Jenny; Jack, Susan M

    2014-03-01

    Although engagement in collaborative practice is reported to support the role transition and retention of new graduate (NG) nurses, it is not known how to promote collaborative practice among these nurses. This mixed methods study explored the team and organizational factors that may predict NG nurse engagement in collaborative practice. A total of 514 NG nurses from Ontario, Canada completed the Collaborative Practice Assessment Tool. Sixteen NG nurses participated in follow-up interviews. The team and organizational predictors of NG engagement in collaborative practice were as follows: satisfaction with the team (β = 0.278; p = 0.000), number of team strategies (β = 0.338; p = 0.000), participation in a mentorship or preceptorship experience (β = 0.137; p = 0.000), accessibility of manager (β = 0.123; p = 0.001), and accessibility and proximity of educator or professional practice leader (β = 0.126; p = 0.001 and β = 0.121; p = 0.002, respectively). Qualitative analysis revealed the team facilitators to be respect, team support and face-to-face interprofessional interactions. Organizational facilitators included supportive leadership, participation in a preceptorship or mentorship experience and time. Interventions designed to facilitate NG engagement in collaborative practice should consider these factors.

  15. Social Strategies during University Studies Predict Early Career Work Burnout and Engagement: 18-Year Longitudinal Study

    Science.gov (United States)

    Salmela-Aro, Katariina; Tolvanen, Asko; Nurmi, Jari-Erik

    2011-01-01

    This longitudinal study spanning 18 years examined the role of social strategies in early career adaptation. The aim was to find out whether individuals' social strategies measured during their university studies had an impact on work burnout and work engagement measured 10-18 years later. A sample of 292 university students completed the SAQ…

  16. Passion and Motivation for Studying: Predicting Academic Engagement and Burnout in University Students

    Science.gov (United States)

    Stoeber, Joachim; Childs, Julian H.; Hayward, Jennifer A.; Feast, Alexandra R.

    2011-01-01

    Research on the dualistic model of passion has investigated harmonious and obsessive passion in many domains. However, few studies have investigated passion for studying and the role passion for studying plays in student engagement and well-being. The present study investigated the relationships between harmonious and obsessive passion for…

  17. Implicit Social Cognitions Predict Sex Differences in Math Engagement and Achievement

    Science.gov (United States)

    Nosek, Brian A.; Smyth, Frederick L.

    2011-01-01

    Gender stereotypes about math and science do not need to be endorsed, or even available to conscious introspection, to contribute to the sex gap in engagement and achievement in science, technology, engineering, and mathematics (STEM). The authors examined implicit math attitudes and stereotypes among a heterogeneous sample of 5,139 participants.…

  18. Performance expectations, personal resources, and job resources : how do they predict work engagement?

    NARCIS (Netherlands)

    Barbier, M.; Hansez, I.; Chmiel, N.; Demerouti, E.

    2013-01-01

    Research on work engagement has mainly focused on the role of job and personal resources and has ignored the possible impact of personal demands workers develop with regard to their work. The aim of our study was to test the reciprocal relationships that job resources, personal resources, and

  19. Motivational indictors predicting the engagement, frequency and adequacy of rainwater tank maintenance

    Science.gov (United States)

    Mankad, Aditi; Greenhill, Murni

    2014-01-01

    Rainwater tank maintenance is a key social behavior in our changing environment, as tanks are being adopted worldwide to augment household water supplies and reduce urban water stress. The maintenance of rainwater tanks in urban areas is an important pro-environmental behavior that prevents public health issues arising from unhygienic tank use. This study examined motivational differences in maintenance behavior between householders with retrofitted and mandated (compulsory) rainwater tanks on their property (N = 1988). Results showed that retrofitted tank owners were more self-determined in their motivation than mandated owners. Amotivation and integrated regulation were both dominant predictors of engagement in tank maintenance, frequency and adequacy of tank maintenance activities. Those involved in more maintenance activity were likely driven to do so because of feelings of adherence to personal goals and values (e.g., as "sustainable" citizens), whereas individuals who experienced a lack of control and alienation from the activity were likely to view maintenance as meaningless. Thus, people with higher integrated regulation engaged in more tank maintenance activities, whereas more amotivated individuals engaged in less maintenance. As cities begin relying more on citizen self-sufficiency with respect to water and energy resources, issues relating to infrastructure maintenance and operation become paramount. Results show that motivation is important in the impetus to engage in a pro-environmental behavior as well as the frequency and accuracy with which that behavior is undertaken. Policy implications are further discussed.

  20. Barriers to Mindfulness: a Path Analytic Model Exploring the Role of Rumination and Worry in Predicting Psychological and Physical Engagement in an Online Mindfulness-Based Intervention.

    Science.gov (United States)

    Banerjee, Moitree; Cavanagh, Kate; Strauss, Clara

    2018-01-01

    Little is known about the factors associated with engagement in mindfulness-based interventions (MBIs). Moreover, engagement in MBIs is usually defined in terms of class attendance ('physical engagement') only. However, in the psychotherapy literature, there is increasing emphasis on measuring participants' involvement with interventions ('psychological engagement'). This study tests a model that rumination and worry act as barriers to physical and psychological engagement in MBIs and that this in turn impedes learning mindfulness. One hundred and twenty-four participants were given access to a 2-week online mindfulness-based self-help (MBSH) intervention. Self-report measures of mindfulness, rumination, worry, positive beliefs about rumination, positive beliefs about worry and physical and psychological engagement were administered. A path analysis was used to test the linear relationships between the variables. Physical and psychological engagement were identified as two distinct constructs. Findings were that rumination and worry both predicted psychological disengagement in MBSH. Psychological engagement predicted change in the describe, act with awareness, non-judge and non-react facets of mindfulness while physical engagement only predicted changes in the non-react facet of mindfulness. Thus, rumination and worry may increase risk of psychological disengagement from MBSH which may in turn hinder cultivating mindfulness. Future suggestions for practice are discussed.

  1. Human amygdala engagement moderated by early life stress exposure is a biobehavioral target for predicting recovery on antidepressants.

    Science.gov (United States)

    Goldstein-Piekarski, Andrea N; Korgaonkar, Mayuresh S; Green, Erin; Suppes, Trisha; Schatzberg, Alan F; Hastie, Trevor; Nemeroff, Charles B; Williams, Leanne M

    2016-10-18

    Amygdala circuitry and early life stress (ELS) are both strongly and independently implicated in the neurobiology of depression. Importantly, animal models have revealed that the contribution of ELS to the development and maintenance of depression is likely a consequence of structural and physiological changes in amygdala circuitry in response to stress hormones. Despite these mechanistic foundations, amygdala engagement and ELS have not been investigated as biobehavioral targets for predicting functional remission in translational human studies of depression. Addressing this question, we integrated human neuroimaging and measurement of ELS within a controlled trial of antidepressant outcomes. Here we demonstrate that the interaction between amygdala activation engaged by emotional stimuli and ELS predicts functional remission on antidepressants with a greater than 80% cross-validated accuracy. Our model suggests that in depressed people with high ELS, the likelihood of remission is highest with greater amygdala reactivity to socially rewarding stimuli, whereas for those with low-ELS exposure, remission is associated with lower amygdala reactivity to both rewarding and threat-related stimuli. This full model predicted functional remission over and above the contribution of demographics, symptom severity, ELS, and amygdala reactivity alone. These findings identify a human target for elucidating the mechanisms of antidepressant functional remission and offer a target for developing novel therapeutics. The results also offer a proof-of-concept for using neuroimaging as a target for guiding neuroscience-informed intervention decisions at the level of the individual person.

  2. Patterns of geographic mobility predict barriers to engagement in HIV care and antiretroviral treatment adherence.

    Science.gov (United States)

    Taylor, Barbara S; Reyes, Emily; Levine, Elizabeth A; Khan, Shah Z; Garduño, L Sergio; Donastorg, Yeycy; Hammer, Scott M; Brudney, Karen; Hirsch, Jennifer S

    2014-06-01

    Migration and geographic mobility increase risk for HIV infection and may influence engagement in HIV care and adherence to antiretroviral therapy. Our goal is to use the migration-linked communities of Santo Domingo, Dominican Republic, and New York City, New York, to determine the impact of geographic mobility on HIV care engagement and adherence to treatment. In-depth interviews were conducted with HIV+Dominicans receiving antiretroviral therapy, reporting travel or migration in the past 6 months and key informants (n=45). Mobility maps, visual representations of individual migration histories, including lifetime residence(s) and all trips over the past 2 years, were generated for all HIV+ Dominicans. Data from interviews and field observation were iteratively reviewed for themes. Mobility mapping revealed five distinct mobility patterns: travel for care, work-related travel, transnational travel (nuclear family at both sites), frequent long-stay travel, and vacation. Mobility patterns, including distance, duration, and complexity, varied by motivation for travel. There were two dominant barriers to care. First, a fear of HIV-related stigma at the destination led to delays seeking care and poor adherence. Second, longer trips led to treatment interruptions due to limited medication supply (30-day maximum dictated by programs or insurers). There was a notable discordance between what patients and providers perceived as mobility-induced barriers to care and the most common barriers found in the analysis. Interventions to improve HIV care for mobile populations should consider motivation for travel and address structural barriers to engagement in care and adherence.

  3. Choice is good, but relevance is excellent: autonomy-enhancing and suppressing teacher behaviours predicting students' engagement in schoolwork.

    Science.gov (United States)

    Assor, Avi; Kaplan, Haya; Roth, Guy

    2002-06-01

    This article examines two questions concerning teacher-behaviours that are characterised in Self-Determination Theory (Ryan & Deci, 2000) as autonomy-supportive or suppressive: (1) Can children differentiate among various types of autonomy-enhancing and suppressing teacher behaviours? (2) Which of those types of behaviour are particularly important in predicting feelings toward and engagement in schoolwork? It was hypothesised that teacher behaviours that help students to understand the relevance of schoolwork for their personal interests and goals are particularly important predictors of engagement in schoolwork. Israeli students in grades 3-5 (N = 498) and in grades 6-8 (N = 364) completed questionnaires assessing the variables of interest. Smallest Space Analyses indicated that both children and early adolescents can differentiate among three types of autonomy enhancing teacher behaviours - fostering relevance, allowing criticism, and providing choice - and three types of autonomy suppressing teacher behaviours - suppressing criticism, intruding, and forcing unmeaningful acts. Regression analyses supported the hypothesis concerning the importance of teacher behaviours that clarify the personal relevance of schoolwork. Among the autonomy-suppressing behaviours, 'Criticism-suppression' was the best predictor of feelings and engagement. The findings underscore the active and empathic nature of teachers' role in supporting students' autonomy, and suggest that autonomy-support is important not only for early adolescents but also for children. Discussion of potential determinants of the relative importance of various autonomy-affecting teacher actions suggests that provision of choice should not always be viewed as a major indicator of autonomy support.

  4. Latent profiles of non-residential father engagement six years after divorce predict long term offspring outcomes

    Science.gov (United States)

    Modecki, Kathryn Lynn; Hagan, Melissa; Sandler, Irwin; Wolchik, Sharlene

    2014-01-01

    This study examined profiles of non-residential father engagement (i.e., support to the adolescent, contact frequency, remarriage, relocation, and interparental conflict) with their adolescent children (N = 156) six to eight years following divorce and the prospective relation between these profiles and the psychosocial functioning of their offspring, nine years later. Parental divorce occurred during late childhood to early adolescence; indicators of non-residential father engagement were assessed during adolescence, and mental health problems and academic achievement of offspring were assessed nine years later in young adulthood. Three profiles of father engagement were identified in our sample of mainly White, non-Hispanic divorced fathers: Moderate Involvement/Low Conflict, Low Involvement/Moderate Conflict, and High Involvement/High Conflict. Profiles differentially predicted offspring outcomes nine years later when they were young adults, controlling for quality of the mother-adolescent relationship, mother’s remarriage, mother’s income, and gender, age and offspring mental health problems in adolescence. Offspring of fathers characterized as Moderate Involvement/Low Conflict had the highest academic achievement and the lowest number of externalizing problems nine years later compared to offspring whose fathers had profiles indicating either the highest or lowest levels of involvement but higher levels of conflict. Results indicate that greater paternal psychosocial support and more frequent father-adolescent contact do not outweigh the negative impact of interparental conflict on youth outcomes in the long-term. Implications of findings for policy and intervention are discussed. PMID:24484456

  5. Does exercise motivation predict engagement in objectively assessed bouts of moderate-intensity exercise? A self-determination theory perspective.

    Science.gov (United States)

    Standage, Martyn; Sebire, Simon J; Loney, Tom

    2008-08-01

    This study examined the utility of motivation as advanced by self-determination theory (Deci & Ryan, 2000) in predicting objectively assessed bouts of moderate intensity exercise behavior. Participants provided data pertaining to their exercise motivation. One week later, participants wore a combined accelerometer and heart rate monitor (Actiheart; Cambridge Neurotechnology Ltd) and 24-hr energy expenditure was estimated for 7 days. After controlling for gender and a combined marker of BMI and waist circumference, results showed autonomous motivation to positively predict moderate-intensity exercise bouts of >or=10 min, or=20 min, and an accumulation needed to meet public health recommendations for moderate intensity activity (i.e., ACSM/AHA guidelines). The present findings add bouts of objectively assessed exercise behavior to the growing body of literature that documents the adaptive consequences of engaging in exercise for autonomous reasons. Implications for practice and future work are discussed.

  6. Students’ engagement with a collaborative wiki tool predicts enhanced written exam performance

    Directory of Open Access Journals (Sweden)

    Tom Stafford

    2014-08-01

    Full Text Available We introduced voluntary wiki-based exercises to a long-running cognitive psychology course, part of the core curriculum for an undergraduate degree in psychology. Over 2 yearly cohorts, students who used the wiki more also scored higher on the final written exam. Using regression analysis, it is possible to account for students’ tendency to score well on other psychology exams, thus statistically removing some obvious candidate third factors, such as general talent or enthusiasm for psychology, which might drive this correlation. Such an analysis shows that both high- and low-grading students who used the wiki got higher scores on the final exam, with engaged wiki users scoring an average of an extra 5 percentage points. We offer an interpretation of the mechanisms of action in terms of the psychological literature on learning and memory.

  7. Integration of Multiple Data Sources for predicting the Engagement of Students in Practical Activities

    Directory of Open Access Journals (Sweden)

    Llanos Tobarra

    2014-09-01

    Full Text Available This work presents the integration of an automatic assessment system for virtual/remote laboratories and the institutional Learning Management System (LMS, in order to analyze the students’ progress and their collaborative learning in virtual/remote laboratories. As a result of this integration, it is feasible to extract useful information for the characterization of the students’ learning process and detecting the students’ engagement with the practical activities of our subjects. From this integration, a dashboard has been created to graphically present to lecturers the analyzed results. Thanks to this, faculty can use the analyzed information in order to guide the learning/teaching process of each student. As an example, a subject focused on the configuration of network services has been chosen to implement our proposal.

  8. EEG Estimates of Cognitive Workload and Engagement Predict Math Problem Solving Outcomes

    Science.gov (United States)

    Beal, Carole R.; Galan, Federico Cirett

    2012-01-01

    In the present study, the authors focused on the use of electroencephalography (EEG) data about cognitive workload and sustained attention to predict math problem solving outcomes. EEG data were recorded as students solved a series of easy and difficult math problems. Sequences of attention and cognitive workload estimates derived from the EEG…

  9. Factors that Predict Full-Time Community College Faculty Engagement in Online Instruction

    Science.gov (United States)

    Akroyd, Duane; Patton, Bess; Bracken, Susan

    2013-01-01

    This study is a secondary quantitative analysis of the 2004 National Study of Postsecondary Faculty (NSOPF) data. It examines the ability of human capital, intrinsic rewards, extrinsic rewards, and gender/race demographics to predict full-time community college faculty teaching on-line courses. Findings indicate that those faculty with higher…

  10. Engagement vs Performance: Using Electronic Portfolios to Predict First Semester Engineering Student Persistence

    Science.gov (United States)

    Aguiar, Everaldo; Ambrose, G. Alex; Chawla, Nitesh V.; Goodrich, Victoria; Brockman, Jay

    2014-01-01

    As providers of higher education begin to harness the power of big data analytics, one very fitting application for these new techniques is that of predicting student attrition. The ability to pinpoint students who might soon decide to drop out, or who may be following a suboptimal path to success, allows those in charge not only to understand the…

  11. Numerical and Experimental Validation of a New Damage Initiation Criterion

    Science.gov (United States)

    Sadhinoch, M.; Atzema, E. H.; Perdahcioglu, E. S.; van den Boogaard, A. H.

    2017-09-01

    Most commercial finite element software packages, like Abaqus, have a built-in coupled damage model where a damage evolution needs to be defined in terms of a single fracture energy value for all stress states. The Johnson-Cook criterion has been modified to be Lode parameter dependent and this Modified Johnson-Cook (MJC) criterion is used as a Damage Initiation Surface (DIS) in combination with the built-in Abaqus ductile damage model. An exponential damage evolution law has been used with a single fracture energy value. Ultimately, the simulated force-displacement curves are compared with experiments to validate the MJC criterion. 7 out of 9 fracture experiments were predicted accurately. The limitations and accuracy of the failure predictions of the newly developed damage initiation criterion will be discussed shortly.

  12. A Failure Criterion for Concrete

    DEFF Research Database (Denmark)

    Ottosen, N. S.

    1977-01-01

    A four-parameter failure criterion containing all the three stress invariants explicitly is proposed for short-time loading of concrete. It corresponds to a smooth convex failure surface with curved meridians, which open in the negative direction of the hydrostatic axis, and the trace in the devi......A four-parameter failure criterion containing all the three stress invariants explicitly is proposed for short-time loading of concrete. It corresponds to a smooth convex failure surface with curved meridians, which open in the negative direction of the hydrostatic axis, and the trace...

  13. Engagement in mobile phone app for self-monitoring of emotional wellbeing predicts changes in mental health: MoodPrism.

    Science.gov (United States)

    Bakker, David; Rickard, Nikki

    2018-02-01

    Mobile apps are being used increasingly for mental health purposes, but evidence of their efficacy remains limited. The mechanisms underlying any effects of such apps are also unclear. This study examined the effectiveness of a self-monitoring mobile phone app by investigating the relationships between app engagement and mental health outcomes. Participants downloaded the MoodPrism app from the iOS and Android app stores, completing in-app assessments at start of use and again 30days later. The app prompted participants daily to complete a short mood questionnaire and formulated their responses into a mood diary. Data from 234 assessment completers (73% female; M age = 34.8 years) were analysed via hierarchical and mediation regressions. In this community sample, app engagement ratings predicted decreases in depression and anxiety, and increases in mental well-being. These effects were mediated by increases in emotional self-awareness, but only for participants who were clinically depressed or anxious at the time of the baseline assessment. Mental health literacy and coping self-efficacy did not play mediating roles. Findings suggest that other influential mediators may have not been measured, and future studies could verify the findings by using alternative methodologies, such as comparison with a control group. Engaging with an emotional wellbeing self-monitoring app may reduce depressive and anxious symptoms, and increase mental well-being. Increases in emotional self-awareness may mediate these changes in clinical populations, and further research is needed to reveal other mechanisms that mental health apps can utilize. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. The prospective usefulness of callous-unemotional traits and conduct disorder in predicting treatment engagement among detained girls.

    Science.gov (United States)

    Colins, Olivier F; Van Damme, Lore; Fanti, Kostas A; Andershed, Henrik

    2017-01-01

    Although treatment engagement (TE) is crucial for treatment success it is not well known how likely detained girls are to engage in treatment and what features may impede them from doing so. This study is the first to examine the prognostic usefulness of two features of potential interest, being callous-unemotional (CU) traits and conduct disorder (CD), in relation to TE. Detained girls and their parents (n = 75) were interviewed with the Diagnostic Interview Schedule for Children to assess CD, and completed the Antisocial Process Screening Device to assess CU traits dimensionally and categorically as in the new diagnostic and statistical manual of mental disorders, fifth edition (DSM-5) CU-based specifier. One to two months later, the girls reported how much they engaged in treatment. At the zero-order level, self-, but not parent-reported CU traits and CD were predictive of lower levels of TE. The incorporation of CU traits into a diagnosis of CD identified girls with lower levels of future TE, a finding that held across different informants. Of note, the aforementioned findings only became apparent when using a dimensional measure of CU traits, and not when using the categorical measure of CU traits currently included in DSM-5. This study showed that CU traits can help developing an understanding of what factors hinder TE among detained girls. Our findings also support recommendations to incorporate CU traits into the CD diagnosis, and suggest that dimensional approaches to do so may yield relevant information about future levels of TE.

  15. Predicting Parents’ School Engagement Among Lesbian, Gay, and Heterosexual Adoptive Parents of Kindergarteners

    Science.gov (United States)

    Goldberg, Abbie E.; Smith, JuliAnna Z.

    2014-01-01

    Little research has explored parental engagement in schools in the context of adoptive parent families or same-sex parent families. The current cross-sectional study explored predictors of parents’ self-reported school involvement, relationships with teachers, and school satisfaction, in a sample of 103 female same-sex, male same-sex, and heterosexual adoptive parent couples (196 parents) of kindergarten-age children. Parents who reported more contact by teachers about positive or neutral topics (e.g., their child’s good grades) reported more involvement and greater satisfaction with schools, regardless of family type. Parents who reported more contact by teachers about negative topics (e.g., their child’s behavior problems) reported better relationships with teachers but lower school satisfaction, regardless of family type. Regarding the broader school context, across all family types, parents who felt more accepted by other parents reported more involvement and better parent–teacher relationships; socializing with other parents was related to greater involvement. Regarding the adoption-specific variables, parents who perceived their children’s schools as more culturally sensitive were more involved and satisfied with the school, regardless of family type. Perceived cultural sensitivity mattered more for heterosexual adoptive parents’ relationships with their teachers than it did for same-sex adoptive parents. Finally, heterosexual adoptive parents who perceived high levels of adoption stigma in their children’s schools were less involved than those who perceived low levels of stigma, whereas same-sex adoptive parents who perceived high levels of stigma were more involved than those who perceived low levels of stigma. Our findings have implications for school professionals, such as school psychologists, who work with diverse families. PMID:25267169

  16. Distance criterion for hydrogen bond

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Distance criterion for hydrogen bond. In a D-H ...A contact, the D...A distance must be less than the sum of van der Waals Radii of the D and A atoms, for it to be a hydrogen bond.

  17. Time to Criterion: An Experimental Study.

    Science.gov (United States)

    Anderson, Lorin W.

    The purpose of the study was to investigate the magnitude of individual differences in time-to-criterion and the stability of these differences. Time-to-criterion was defined in two ways: the amount of elapsed time required to attain the criterion level and the amount of on-task time required to attain the criterion level. Ninety students were…

  18. Nonparametric adaptive age replacement with a one-cycle criterion

    International Nuclear Information System (INIS)

    Coolen-Schrijner, P.; Coolen, F.P.A.

    2007-01-01

    Age replacement of technical units has received much attention in the reliability literature over the last four decades. Mostly, the failure time distribution for the units is assumed to be known, and minimal costs per unit of time is used as optimality criterion, where renewal reward theory simplifies the mathematics involved but requires the assumption that the same process and replacement strategy continues over a very large ('infinite') period of time. Recently, there has been increasing attention to adaptive strategies for age replacement, taking into account the information from the process. Although renewal reward theory can still be used to provide an intuitively and mathematically attractive optimality criterion, it is more logical to use minimal costs per unit of time over a single cycle as optimality criterion for adaptive age replacement. In this paper, we first show that in the classical age replacement setting, with known failure time distribution with increasing hazard rate, the one-cycle criterion leads to earlier replacement than the renewal reward criterion. Thereafter, we present adaptive age replacement with a one-cycle criterion within the nonparametric predictive inferential framework. We study the performance of this approach via simulations, which are also used for comparisons with the use of the renewal reward criterion within the same statistical framework

  19. Role of Procrastination and Motivational Self-Regulation in Predicting Students\\' Behavioral Engagement

    Directory of Open Access Journals (Sweden)

    Abbasi M

    2015-12-01

    Full Text Available Aims: As an important intervening factor to enhance educational and motivational performance of the students, understating the effective factors on behavioral enthusiasm plays a very important role. The aim of this study was to explain the role of motivational self-regulation and procrastination in predicting the students’ behavioral enthusiasm.  Instrument & Methods: In the correlational descriptive cross-sectional study, 311 students of Arak University of Medical Sciences were selected via Available Sampling using Cochran’s Formula in 2014-15 academic year. Data was collected, using Students’ Educational Procrastination Scale, Motivational Self-regulating Scale, and Behavioral Enthusiasm Scale. Data was analyzed in SPSS 19 software using Pearson Correlation Coefficient, and Multiple Regression Analysis. Findings: The highest and the lowest correlations were between procrastination and behavioral enthusiasm and between environmental control and behavioral enthusiasm, respectively (p<0.05. There was a positive and significant correlation between self-regulation and behavioral enthusiasm. In addition, there was a negative and significant correlation between procrastination and behavioral enthusiasm (p<0.001. Totally, procrastination (β=-0.233 and motivational self-regulation (β=0.238 explained 10% of the students’ behavioral enthusiasm variance (p<0.001; R²=0.102. Conclusion: Any reduction in procrastination and any enhancement in motivational self-regulation can enhance the students’ behavioral enthusiasm. 

  20. Extensions and applications of the Bohm criterion

    Science.gov (United States)

    Baalrud, Scott D.; Scheiner, Brett; Yee, Benjamin; Hopkins, Matthew; Barnat, Edward

    2015-04-01

    The generalized Bohm criterion is revisited in the context of incorporating kinetic effects of the electron and ion distribution functions into the theory. The underlying assumptions and results of two different approaches are compared: the conventional ‘kinetic Bohm criterion’ and a fluid-moment hierarchy approach. The former is based on the asymptotic limit of an infinitely thin sheath (λD/l = 0), whereas the latter is based on a perturbative expansion of a sheath that is thin compared to the plasma (λD/l ≪ 1). Here λD is the Debye length, which characterizes the sheath length scale, and l is a measure of the plasma or presheath length scale. The consequences of these assumptions are discussed in terms of how they restrict the class of distribution functions to which the resulting criteria can be applied. Two examples are considered to provide concrete comparisons between the two approaches. The first is a Tonks-Langmuir model including a warm ion source (Robertson 2009 Phys. Plasmas 16 103503). This highlights a substantial difference between the conventional kinetic theory, which predicts slow ions dominate at the sheath edge, and the fluid moment approach, which predicts slow ions have little influence. The second example considers planar electrostatic probes biased near the plasma potential using model equations and particle-in-cell simulations. This demonstrates a situation where electron kinetic effects alter the Bohm criterion, leading to a subsonic ion flow at the sheath edge.

  1. Inviscid criterion for decomposing scales

    Science.gov (United States)

    Zhao, Dongxiao; Aluie, Hussein

    2018-05-01

    The proper scale decomposition in flows with significant density variations is not as straightforward as in incompressible flows, with many possible ways to define a "length scale." A choice can be made according to the so-called inviscid criterion [Aluie, Physica D 24, 54 (2013), 10.1016/j.physd.2012.12.009]. It is a kinematic requirement that a scale decomposition yield negligible viscous effects at large enough length scales. It has been proved [Aluie, Physica D 24, 54 (2013), 10.1016/j.physd.2012.12.009] recently that a Favre decomposition satisfies the inviscid criterion, which is necessary to unravel inertial-range dynamics and the cascade. Here we present numerical demonstrations of those results. We also show that two other commonly used decompositions can violate the inviscid criterion and, therefore, are not suitable to study inertial-range dynamics in variable-density and compressible turbulence. Our results have practical modeling implication in showing that viscous terms in Large Eddy Simulations do not need to be modeled and can be neglected.

  2. On the Modified Barkhausen Criterion

    DEFF Research Database (Denmark)

    Lindberg, Erik; Murali, K.

    2016-01-01

    Oscillators are normally designed according to the Modified Barkhausen Criterion i.e. the complex pole pair is moved out in RHP so that the linear circuit becomes unstable. By means of the Mancini Phaseshift Oscillator it is demonstrated that the distortion of the oscillator may be minimized by i...... by introducing a nonlinear ”Hewlett Resistor” so that the complex pole-pair is in the RHP for small signals and in the LHP for large signals i.e. the complex pole pair of the instant linearized small signal model is moving around the imaginary axis in the complex frequency plane....

  3. Towards chaos criterion in quantum field theory

    OpenAIRE

    Kuvshinov, V. I.; Kuzmin, A. V.

    2002-01-01

    Chaos criterion for quantum field theory is proposed. Its correspondence with classical chaos criterion in semi-classical regime is shown. It is demonstrated for real scalar field that proposed chaos criterion can be used to investigate stability of classical solutions of field equations.

  4. Bell's theorem based on a generalized EPR criterion of reality

    International Nuclear Information System (INIS)

    Eberhard, P.H.; Rosselet, P.

    1995-01-01

    First, the demonstration of Bell's theorem, i.e., of the nonlocal character of quantum theory, is spelled out using the EPR criterion of reality as premises and a gedanken experiment involving two particles. Then, the EPR criterion is extended to include quantities predicted almost with certainty, and Bell's theorem is demonstrated on these new premises. The same experiment is used but in conditions that become possible in real life, without the requirements of ideal efficiencies and zero background. Very high efficiencies and low background are needed, but these requirements may be met in the future

  5. Bell's theorem based on a generalized EPR criterion of reality

    International Nuclear Information System (INIS)

    Eberhard, P.H.; Rosselet, P.

    1993-04-01

    First, the demonstration of Bell's theorem, i.e. of the non-local character of quantum theory, is spelled out using the EPR criterion of reality as premises and a gedanken experiment involving two particles. Then, the EPR criterion is extended to include quantities predicted almost with certainty, and Bell's theorem is demonstrated on these new premises. The same experiment is used but in conditions that become possible in real life, without the requirements of ideal efficiencies and zero background. Very high efficiencies and low background are needed, but these requirements may be met in the future. (author) 1 fig., 11 refs

  6. The Bohm criterion for rf discharges

    International Nuclear Information System (INIS)

    Meijer, P.M.; Goedheer, W.J.

    1991-01-01

    The well-known dc Bohm criterion is extended to rf discharges. Both low- (ω rf much-lt ω pi ) and high-(ω pi much-lt ω rf ) frequency regimes are considered. For low frequencies, the dc Bohm criterion holds. This criterion states that the initial energy of the ions entering the sheath must exceed a limit in order to obtain a stable sheath. For high frequencies, a modified limit is derived, which is somewhat lower than that of the dc Bohm criterion. The resulting ion current density in a high-frequency sheath is only a few percent lower than that for the dc case

  7. Religious Engagement in a Risky Family Model Predicting Health in Older Black and White Seventh-day Adventists.

    Science.gov (United States)

    Morton, Kelly R; Lee, Jerry W; Haviland, Mark G; Fraser, Gary E

    2012-11-01

    In a structural equation model, associations among latent variables - Child Poverty, Risky Family exposure, Religious Engagement, Negative Social Interactions, Negative Emotionality, and Perceived Physical Health - were evaluated in 6,753 Black and White adults aged 35-106 years (M = 60.5, SD = 13.0). All participants were members of the Seventh-day Adventist church surveyed in the Biopsychosocial Religion and Health Study (BRHS). Child Poverty was positively associated with both Risky Family exposure (conflict, neglect, abuse) and Religious Engagement (intrinsic religiosity, religious coping, religiousness). Risky Family was negatively associated with Religious Engagement and positively associated with both Negative Social Interactions (intrusive, failed to help, insensitive, rejecting) and Negative Emotionality (depression, negative affect, neuroticism). Religious Engagement was negatively associated with Negative Emotionality and Negative Social Interactions at a given level of risky family. Negative Social Interactions was positively associated with Negative Emotionality, which had a direct, negative effect on Perceived Physical Health. All constructs had indirect effects on Perceived Physical Health through Negative Emotionality. The effects of a risky family environment appear to be enduring, negatively affecting one's adult religious life, emotionality, social interactions, and perceived health. Religious engagement, however, may counteract the damaging effects of early life stress.

  8. An Elasto-Plastic Damage Model for Rocks Based on a New Nonlinear Strength Criterion

    Science.gov (United States)

    Huang, Jingqi; Zhao, Mi; Du, Xiuli; Dai, Feng; Ma, Chao; Liu, Jingbo

    2018-05-01

    The strength and deformation characteristics of rocks are the most important mechanical properties for rock engineering constructions. A new nonlinear strength criterion is developed for rocks by combining the Hoek-Brown (HB) criterion and the nonlinear unified strength criterion (NUSC). The proposed criterion takes account of the intermediate principal stress effect against HB criterion, as well as being nonlinear in the meridian plane against NUSC. Only three parameters are required to be determined by experiments, including the two HB parameters σ c and m i . The failure surface of the proposed criterion is continuous, smooth and convex. The proposed criterion fits the true triaxial test data well and performs better than the other three existing criteria. Then, by introducing the Geological Strength Index, the proposed criterion is extended to rock masses and predicts the test data well. Finally, based on the proposed criterion, a triaxial elasto-plastic damage model for intact rock is developed. The plastic part is based on the effective stress, whose yield function is developed by the proposed criterion. For the damage part, the evolution function is assumed to have an exponential form. The performance of the constitutive model shows good agreement with the results of experimental tests.

  9. Predicting Early Adolescents' Academic Achievement, Social Competence, and Physical Health from Parenting, Ego Resilience, and Engagement Coping

    Science.gov (United States)

    Swanson, Jodi; Valiente, Carlos; Lemery-Chalfant, Kathryn; O'Brien, T. Caitlin

    2011-01-01

    This study examined ego resilience and engagement coping as mediators of the relationships between supportive and controlling parenting practices and early adolescents' academic achievement, social competence, and physical health. Participants were 240 predominantly Mexican American early adolescents, their parents, and their teachers. There were…

  10. How Cognitive Engagement Fluctuates during a Team-Based Learning Session and How It Predicts Academic Achievement

    Science.gov (United States)

    Rotgans, Jerome I.; Schmidt, Henk G.; Rajalingam, Preman; Hao, Joey Wong Ying; Canning, Claire Ann; Ferenczi, Michael A.; Low-Beer, Naomi

    2018-01-01

    The objective of the paper is to report findings of two studies that attempted to find answers to the following questions: (1) What are the levels of cognitive engagement in TBL?; (2) Are there differences between students who were more exposed to TBL than students who were less exposed to TBL?; (3) To which extent does cognitive engagement…

  11. Beyond School Records: The Value of Cognitive and Affective Engagement in Predicting Dropout and On-Time Graduation

    Science.gov (United States)

    Lovelace, Matthew D.; Reschly, Amy L.; Appleton, James J.

    2018-01-01

    Early warning systems use school record data--such as attendance rate, behavior records, and course performance--to identify students at risk of dropping out. These are useful predictors of graduation-related outcomes, in large part because they indicate a student's level of engagement with school. However, these data do not indicate how invested…

  12. Plasma sheath criterion in thermal electronegative plasmas

    International Nuclear Information System (INIS)

    Ghomi, Hamid; Khoramabadi, Mansour; Ghorannevis, Mahmod; Shukla, Padma Kant

    2010-01-01

    The sheath formation criterion in electronegative plasma is examined. By using a multifluid model, it is shown that in a collisional sheath there will be upper as well as lower limits for the sheath velocity criterion. However, the parameters of the negative ions only affect the lower limit.

  13. Ten Issues in Criterion-Referenced Testing: A Response to Commonly Heard Criticisms.

    Science.gov (United States)

    Curlette, William L.; Stallings, William M.

    1979-01-01

    The 10 criticisms of criterion-referenced tests addressed in this paper are: the domains tested; pedagogical influence; difficulty of items; cumbersome reports; reliability; arbitrary criteria; local objectives; labeling; predictive validity; and repeated testing. (SJL)

  14. A food-predictive cue attributed with incentive salience engages subcortical afferents and efferents of the paraventricular nucleus of the thalamus.

    Science.gov (United States)

    Haight, Joshua L; Fuller, Zachary L; Fraser, Kurt M; Flagel, Shelly B

    2017-01-06

    The paraventricular nucleus of the thalamus (PVT) has been implicated in behavioral responses to reward-associated cues. However, the precise role of the PVT in these behaviors has been difficult to ascertain since Pavlovian-conditioned cues can act as both predictive and incentive stimuli. The "sign-tracker/goal-tracker" rat model has allowed us to further elucidate the role of the PVT in cue-motivated behaviors, identifying this structure as a critical component of the neural circuitry underlying individual variation in the propensity to attribute incentive salience to reward cues. The current study assessed differences in the engagement of specific PVT afferents and efferents in response to presentation of a food-cue that had been attributed with only predictive value or with both predictive and incentive value. The retrograde tracer fluorogold (FG) was injected into the PVT or the nucleus accumbens (NAc) of rats, and cue-induced c-Fos in FG-labeled cells was quantified. Presentation of a predictive stimulus that had been attributed with incentive value elicited c-Fos in PVT afferents from the lateral hypothalamus, medial amygdala (MeA), and the prelimbic cortex (PrL), as well as posterior PVT efferents to the NAc. PVT afferents from the PrL also showed elevated c-Fos levels following presentation of a predictive stimulus alone. Thus, presentation of an incentive stimulus results in engagement of subcortical brain regions; supporting a role for the hypothalamic-thalamic-striatal axis, as well as the MeA, in mediating responses to incentive stimuli; whereas activity in the PrL to PVT pathway appears to play a role in processing the predictive qualities of reward-paired stimuli. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. An ethical criterion for geoscientists

    Science.gov (United States)

    Peppoloni, Silvia

    2013-04-01

    Anthropological researches have demonstrated that at some point in human history, man makes an evolutive jump in cultural sense: at first, he is able to perceive himself only as part of a community, later he becomes able to perceive himself as an individual. The analysis of the linguistic roots of the word "Ethics" discloses the traces of this evolutive transition and an original double meaning: on the one hand, "Ethics" contains a sense of belonging to the social fabric, on the other hand, it is related to the individual sphere. These two existential conditions (social and individual) unexpectedly co-exist in the word "Ethics". So, "Geo-Ethics" can be defined as the investigation and reflection on those values upon which to base appropriate behaviours and practices regarding the Geosphere (social dimension), but also as the analysis of the relationships between the geoscientist who acts and his own actions (individual dimension). Therefore, the meaning of the word "Geo-Ethics" calls upon geoscientists to face the responsibility of an ethical behaviour. What does this responsibility consist of and what motivations are necessary to push geoscientists to practice the Earth sciences in an ethical way? An ethical commitment exists if there is research of truth. In their activities, Geoscientists should be searchers and defenders of truth. If geoscientists give up this role, they completely empty of meaning their work. Ethical obligations arise from the possession of specific knowledge that has practical consequences. Geoscientists, as active and responsible part of society, have to serve society and the common good. The ethical criterion for a geoscientist should be rooted in his individual sphere, that is the source of any action even in the social sphere, and should have the intellectual honesty as main requirement. It includes: • respect for the truth that they look for and for other's ideas; • recognition of the value of others as valuable for themselves;

  16. A simple stability criterion for CANDU figure-of-eight flow oscillations

    International Nuclear Information System (INIS)

    Gulshani, P.; Spinks, N.J.

    1983-01-01

    Potential flow oscillations in CANDU reactor primary heat transport system are analyzed in terms of a simple, linearized model. A simple, algebraic stability criterion is obtained. The model predictions are found to be in good agreement with those of thermohydraulic codes for high pressure natural circulation conditions. For normal operating conditions the criterion predicts the correct trend but overlooks important stabilizing effects. The model clarifies the instability mechanism; namely the response of enthalpy and, hence, pressure in the boiling region to flow change

  17. The qualitative criterion of transient angle stability

    DEFF Research Database (Denmark)

    Lyu, R.; Xue, Y.; Xue, F.

    2015-01-01

    In almost all the literatures, the qualitative assessment of transient angle stability extracts the angle information of generators based on the swing curve. As the angle (or angle difference) of concern and the threshold value rely strongly on the engineering experience, the validity and robust...... of these criterions are weak. Based on the stability mechanism from the extended equal area criterion (EEAC) theory and combining with abundant simulations of real system, this paper analyzes the criterions in most literatures and finds that the results could be too conservative or too optimistic. It is concluded...

  18. A work criterion for plastic collapse

    International Nuclear Information System (INIS)

    Muscat, Martin; Mackenzie, Donald; Hamilton, Robert

    2003-01-01

    A new criterion for evaluating limit and plastic loads in pressure vessel design by analysis is presented. The proposed criterion is based on the plastic work dissipated in the structure as loading progresses and may be used for structures subject to a single load or a combination of multiple loads. Example analyses show that limit and plastic loads given by the plastic work criterion are robust and consistent. The limit and plastic loads are determined purely by the inelastic response of the structure and are not influenced by the initial elastic response: a problem with some established plastic criteria

  19. The stressor criterion for posttraumatic stress disorder: Does it matter?

    Science.gov (United States)

    Roberts, Andrea L.; Dohrenwend, Bruce P.; Aiello, Allison; Wright, Rosalind J.; Maercker, Andreas; Galea, Sandro; Koenen, Karestan C.

    2013-01-01

    Objective The definition of the stressor criterion for posttraumatic stress disorder (“Criterion A1”) is hotly debated with major revisions being considered for DSM-V. We examine whether symptoms, course, and consequences of PTSD vary predictably with the type of stressful event that precipitates symptoms. Method We used data from the 2009 PTSD diagnostic subsample (N=3,013) of the Nurses Health Study II. We asked respondents about exposure to stressful events qualifying under 1) DSM-III, 2) DSM-IV, or 3) not qualifying under DSM Criterion A1. Respondents selected the event they considered worst and reported subsequent PTSD symptoms. Among participants who met all other DSM-IV PTSD criteria, we compared distress, symptom severity, duration, impairment, receipt of professional help, and nine physical, behavioral, and psychiatric sequelae (e.g. physical functioning, unemployment, depression) by precipitating event group. Various assessment tools were used to determine fulfillment of PTSD Criteria B through F and to assess these 14 outcomes. Results Participants with PTSD from DSM-III events reported on average 1 more symptom (DSM-III mean=11.8 symptoms, DSM-IV=10.7, non-DSM=10.9) and more often reported symptoms lasted one year or longer compared to participants with PTSD from other groups. However, sequelae of PTSD did not vary systematically with precipitating event type. Conclusions Results indicate the stressor criterion as defined by the DSM may not be informative in characterizing PTSD symptoms and sequelae. In the context of ongoing DSM-V revision, these results suggest that Criterion A1 could be expanded in DSM-V without much consequence for our understanding of PTSD phenomenology. Events not considered qualifying stressors under the DSM produced PTSD as consequential as PTSD following DSM-III events, suggesting PTSD may be an aberrantly severe but nonspecific stress response syndrome. PMID:22401487

  20. A New Multiaxial High-Cycle Fatigue Criterion Based on the Critical Plane for Ductile and Brittle Materials

    Science.gov (United States)

    Wang, Cong; Shang, De-Guang; Wang, Xiao-Wei

    2015-02-01

    An improved high-cycle multiaxial fatigue criterion based on the critical plane was proposed in this paper. The critical plane was defined as the plane of maximum shear stress (MSS) in the proposed multiaxial fatigue criterion, which is different from the traditional critical plane based on the MSS amplitude. The proposed criterion was extended as a fatigue life prediction model that can be applicable for ductile and brittle materials. The fatigue life prediction model based on the proposed high-cycle multiaxial fatigue criterion was validated with experimental results obtained from the test of 7075-T651 aluminum alloy and some references.

  1. Generalized Majority Logic Criterion to Analyze the Statistical Strength of S-Boxes

    Science.gov (United States)

    Hussain, Iqtadar; Shah, Tariq; Gondal, Muhammad Asif; Mahmood, Hasan

    2012-05-01

    The majority logic criterion is applicable in the evaluation process of substitution boxes used in the advanced encryption standard (AES). The performance of modified or advanced substitution boxes is predicted by processing the results of statistical analysis by the majority logic criteria. In this paper, we use the majority logic criteria to analyze some popular and prevailing substitution boxes used in encryption processes. In particular, the majority logic criterion is applied to AES, affine power affine (APA), Gray, Lui J, residue prime, S8 AES, Skipjack, and Xyi substitution boxes. The majority logic criterion is further extended into a generalized majority logic criterion which has a broader spectrum of analyzing the effectiveness of substitution boxes in image encryption applications. The integral components of the statistical analyses used for the generalized majority logic criterion are derived from results of entropy analysis, contrast analysis, correlation analysis, homogeneity analysis, energy analysis, and mean of absolute deviation (MAD) analysis.

  2. Combining University Student Self-Regulated Learning Indicators and Engagement with Online Learning Events to Predict Academic Performance

    Science.gov (United States)

    Pardo, Abelardo; Han, Feifei; Ellis, Robert A.

    2017-01-01

    Self-regulated learning theories are used to understand the reasons for different levels of university student academic performance. Similarly, learning analytics research proposes the combination of detailed data traces derived from technology-mediated tasks with a variety of algorithms to predict student academic performance. The former approach…

  3. The EMU debt criterion: an interpretation

    Directory of Open Access Journals (Sweden)

    R. BERNDSEN

    1997-12-01

    Full Text Available The convergence criteria specified in the Maastricht Treaty on government deficit and debt, inflation, the exchange rate and the long-term interest rate will play an important, if not decisive, role in determining which countries move on to the third stage of the Economic and Monetary Union (EMU. The aim of this work is to provide a possible interpretation of the EMU debt criterion. The author investigates the government debt criterion which, as Article 104c(2b of the Treaty shows, has a considerable scope for interpretation. Although this subject has been discussed extensively, relatively little work has been done to develop a clear interpretation of the EMU debt criterion. A flexible approach is adopted in which parts of the relevant Treaty text are characterised using two parameters.

  4. FFTBM and primary pressure acceptance criterion

    International Nuclear Information System (INIS)

    Prosek, A.

    2004-01-01

    When thermalhydraulic computer codes are used for simulation in the area of nuclear engineering the question is how to conduct an objective comparison between the code calculation and measured data. To answer this the fast Fourier transform based method (FFTBM) was developed. When the FFTBM method was developed the acceptance criteria for primary pressure and total accuracy were set. In the recent study the FFTBM method was used for accuracy quantification of RD-14M large LOCA test B9401 calculations. The blind accuracy analysis indicated good total accuracy while the primary pressure criterion was not fulfilled. The objective of the study was therefore to investigate the reasons for not fulfilling the primary pressure acceptance criterion and the applicability of the criterion to experimental facilities simulating heavy water reactor. The results of the open quantitative analysis showed that sensitivity analysis for influence parameters provide sufficient information to judge in which calculation the accuracy of primary pressure is acceptable. (author)

  5. How personal resources predict work engagement and self-rated performance among construction workers: A social cognitive perspective

    OpenAIRE

    Lorente Prieto, Laura; Salanova Soria, Marisa; Martínez Martínez, Isabel M.; Vera Perea, María

    2014-01-01

    Traditionally, research focussing on psychosocial factors in the construction industry has focused mainly on the negative aspects of health and on results such as occupational accidents. This study, however, focuses on the specific relationships among the different positive psychosocial factors shared by construction workers that could be responsible for occupational well-being and outcomes such as performance. The main objective of this study was to test whether personal resources predict se...

  6. Student Engagement

    DEFF Research Database (Denmark)

    Conduit, Jodie; Karpen, Ingo; Farrelly, Francis

    2017-01-01

    system (the university), the narrow service system (the course), and the individual dyadic level of engagement (the student-lecturer interaction). These findings could be further considered and empirically tested in other engagement contexts (e.g. employee engagement, customer engagement).......Universities are seeking to actively and strategically manage student engagement through providing opportunities for students to interact and engage with the institution on a range of levels and in different ways. However, this increasingly complex and multi-layered nature of student engagement...... within a tertiary education environment is not well understood. Through qualitative focus groups and a series of interviews with undergraduate and postgraduate students, this study explores and articulates the cognitive, emotional, behavioural and social dimensions of engagement that depict the nature...

  7. General stability criterion for inviscid parallel flow

    International Nuclear Information System (INIS)

    Sun Liang

    2007-01-01

    Arnol'd's second stability theorem is approached from an elementary point of view. First, a sufficient criterion for stability is found analytically as either -μ 1 s ) s ) in the flow, where U s is the velocity at the inflection point, and μ 1 is the eigenvalue of Poincare's problem. Second, this criterion is generalized to barotropic geophysical flows in the β plane. And the connections between present criteria and Arnol'd's nonlinear criteria are also discussed. The proofs are completely elementary and so could be used to teach undergraduate students

  8. Sampling Criterion for EMC Near Field Measurements

    DEFF Research Database (Denmark)

    Franek, Ondrej; Sørensen, Morten; Ebert, Hans

    2012-01-01

    An alternative, quasi-empirical sampling criterion for EMC near field measurements intended for close coupling investigations is proposed. The criterion is based on maximum error caused by sub-optimal sampling of near fields in the vicinity of an elementary dipole, which is suggested as a worst......-case representative of a signal trace on a typical printed circuit board. It has been found that the sampling density derived in this way is in fact very similar to that given by the antenna near field sampling theorem, if an error less than 1 dB is required. The principal advantage of the proposed formulation is its...

  9. A new objective criterion for IRIS localization

    International Nuclear Information System (INIS)

    Basit, A.

    2010-01-01

    Iris localization is the most important step in iris recognition systems. For commonly used databases, exact data is not given which describe the true results of localization. To cope with this problem a new objective criterion for iris localization is proposed in this paper based on our visual system. A specific number of points are selected on pupil boundary, iris boundary, upper eyelid and lower eyelid using the original image and then distance from these points to the result of complete iris localization has been calculated. If the determined distance is below a certain threshold then iris localization is considered correct. Experimental results show that proposed criterion is very effective. (author)

  10. Nucleation of recrystallization in fine-grained materials: an extension of the Bailey-Hirsch criterion

    Science.gov (United States)

    Favre, Julien; Fabrègue, Damien; Chiba, Akihiko; Bréchet, Yves

    2013-11-01

    A new criterion for nucleation in the case of dynamic recrystallization is proposed in order to include the contribution of the grain boundary energy stored in the microstructure in the energy balance. Due to the nucleation events, the total surface area of pre-existing grain boundaries decreases, leading to a nucleus size smaller than expected by conventional nucleation criteria. The new model provides a better prediction of the nucleus size during recrystallization of pure copper compared with the conventional nucleation criterion.

  11. A pellet-clad interaction failure criterion

    International Nuclear Information System (INIS)

    Howl, D.A.; Coucill, D.N.; Marechal, A.J.C.

    1983-01-01

    A Pellet-Clad Interaction (PCI) failure criterion, enabling the number of fuel rod failures in a reactor core to be determined for a variety of normal and fault conditions, is required for safety analysis. The criterion currently being used for the safety analysis of the Pressurized Water Reactor planned for Sizewell in the UK is defined and justified in this paper. The criterion is based upon a threshold clad stress which diminishes with increasing fast neutron dose. This concept is consistent with the mechanism of clad failure being stress corrosion cracking (SCC); providing excess corrodant is always present, the dominant parameter determining the propagation of SCC defects is stress. In applying the criterion, the SLEUTH-SEER 77 fuel performance computer code is used to calculate the peak clad stress, allowing for concentrations due to pellet hourglassing and the effect of radial cracks in the fuel. The method has been validated by analysis of PCI failures in various in-reactor experiments, particularly in the well-characterised power ramp tests in the Steam Generating Heavy Water Reactor (SGHWR) at Winfrith. It is also in accord with out-of-reactor tests with iodine and irradiated Zircaloy clad, such as those carried out at Kjeller in Norway. (author)

  12. The Leadership Criterion in Technological Institute

    International Nuclear Information System (INIS)

    Carvalho, Marcelo Souza de; Cussa, Adriana Lourenco d'Avila; Suita, Julio Cezar

    2005-01-01

    This paper introduces the Direction's 'Decision Making Practice'. It has recently been reviewed with the merging of the beddings of the Leadership Criterion (CE-PNQ). These changes improved the control of institutional plans of action which are the result of the global performance critical analysis and other information associated with the Decision Making Practice. (author)

  13. Mercier criterion for high-β tokamaks

    International Nuclear Information System (INIS)

    Galvao, R.M.O.

    1984-01-01

    An expression, for the application of the Mercier criterion to numerical studies of diffuse high-β tokamaks (β approximatelly Σ,q approximatelly 1), which contains only leading order contributions in the high-β tokamak approximation is derived. (L.C.) [pt

  14. Information criterion for the categorization quality evaluation

    Directory of Open Access Journals (Sweden)

    Michail V. Svirkin

    2011-05-01

    Full Text Available The paper considers the possibility of using the variation of information function as a quality criterion for categorizing a collection of documents. The performance of the variation of information function is being examined subject to the number of categories and the sample volume of the test document collection.

  15. Selecting Items for Criterion-Referenced Tests.

    Science.gov (United States)

    Mellenbergh, Gideon J.; van der Linden, Wim J.

    1982-01-01

    Three item selection methods for criterion-referenced tests are examined: the classical theory of item difficulty and item-test correlation; the latent trait theory of item characteristic curves; and a decision-theoretic approach for optimal item selection. Item contribution to the standardized expected utility of mastery testing is discussed. (CM)

  16. A scale invariance criterion for LES parametrizations

    Directory of Open Access Journals (Sweden)

    Urs Schaefer-Rolffs

    2015-01-01

    Full Text Available Turbulent kinetic energy cascades in fluid dynamical systems are usually characterized by scale invariance. However, representations of subgrid scales in large eddy simulations do not necessarily fulfill this constraint. So far, scale invariance has been considered in the context of isotropic, incompressible, and three-dimensional turbulence. In the present paper, the theory is extended to compressible flows that obey the hydrostatic approximation, as well as to corresponding subgrid-scale parametrizations. A criterion is presented to check if the symmetries of the governing equations are correctly translated into the equations used in numerical models. By applying scaling transformations to the model equations, relations between the scaling factors are obtained by demanding that the mathematical structure of the equations does not change.The criterion is validated by recovering the breakdown of scale invariance in the classical Smagorinsky model and confirming scale invariance for the Dynamic Smagorinsky Model. The criterion also shows that the compressible continuity equation is intrinsically scale-invariant. The criterion also proves that a scale-invariant turbulent kinetic energy equation or a scale-invariant equation of motion for a passive tracer is obtained only with a dynamic mixing length. For large-scale atmospheric flows governed by the hydrostatic balance the energy cascade is due to horizontal advection and the vertical length scale exhibits a scaling behaviour that is different from that derived for horizontal length scales.

  17. Maladaptive cognitions predict changes in problematic gaming in highly-engaged adults: A 12-month longitudinal study.

    Science.gov (United States)

    Forrest, Cameron J; King, Daniel L; Delfabbro, Paul H

    2017-02-01

    Understanding the role of maladaptive gaming-related cognitions may assist in screening and interventions for problematic gaming, including Internet gaming disorder (IGD). Cognitive-behavioural interventions that target specific cognitions related to gaming may be more effective than more general approaches that focus only on preoccupation with games. Although past research has identified cross-sectional associations between maladaptive cognitions and problematic gaming, it is less clear whether these cognitions can predict future changes in problematic gaming behaviour. The present study employed an 18-item measure of gaming cognition, assessing perfectionism, cognitive salience, regret, and behavioural salience, to investigate potential changes in problematic gaming over a 12-month period. The sample included 465 Australian adults (84% male, M age =26.2years). It was found that individuals who became problematic gamers over 12months had higher baseline scores on perfectionism (d=1.20), cognitive salience (d=0.74) and regret (d=0.69) than those who remained non-problematic gamers. Problematic gamers who became non-problematic gamers had lower baseline perfectionism scores (d=0.62) than those who remained problematic gamers. Cognitive change accounted for an additional 28% of variance in problematic gaming scores beyond gender, age, and frequency of gaming. These findings suggest that maladaptive gaming-related cognitions could be screened in clinical trials to aid in case formulation and inform decisions on needed interventions to deliver optimal client outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. An instrument based on protection motivation theory to predict Chinese adolescents' intention to engage in protective behaviors against schistosomiasis.

    Science.gov (United States)

    Xiao, Han; Peng, Minjin; Yan, Hong; Gao, Mengting; Li, Jingjing; Yu, Bin; Wu, Hanbo; Li, Shiyue

    2016-01-01

    Further advancement in schistosomiasis prevention requires new tools to assess protective motivation, and promote innovative intervention program. This study aimed to develop and evaluate an instrument developed based on the Protection Motivation Theory (PMT) to predict protective behavior intention against schistosomiasis among adolescents in China. We developed the Schistosomiasis PMT Scale based on two appraisal pathways of protective motivation- threat appraisal pathway and coping appraisal pathway. Data from a large sample of middle school students ( n  = 2238, 51 % male, mean age 13.13 ± 1.10) recruited in Hubei, China was used to evaluated the validity and reliability of the scale. The final scale contains 18 items with seven sub-constructs. Cronbach's Alpha coefficients for the entire instrument was 0.76, and for the seven sub-constructs of severity, vulnerability, intrinsic reward, extrinsic reward, response efficacy, self-efficacy and response cost was 0.56, 0.82, 0.75, 0.80, 0.90, 0.72 and 0.70, respectively. The construct validity analysis revealed that the one level 7 sub-constructs model fitted data well (GFI = 0.98, CFI = 0.98, RMSEA = 0.03, Chi-sq/df = 3.90, p  motivation in schistosomiasis prevention control. Further studies are needed to develop more effective intervention programs for schistosomiasis prevention.

  19. Shrinkage Porosity Criterion and Its Application to A 5.5 Ton Steel Ingot

    Directory of Open Access Journals (Sweden)

    Zhang C.

    2016-06-01

    Full Text Available In order to predict the distribution of shrinkage porosity in steel ingot efficiently and accurately, a criterion R√L and a method to obtain its threshold value were proposed. The criterion R√L was derived based on the solidification characteristics of steel ingot and pressure gradient in the mushy zone, in which the physical properties, the thermal parameters, the structure of the mushy zone and the secondary dendrite arm spacing were all taken into consideration. The threshold value of the criterion R√L was obtained with combination of numerical simulation of ingot solidification and total solidification shrinkage rate. Prediction of the shrinkage porosity in a 5.5 ton ingot of 2Cr13 steel with criterion R√L>0.21 m · °C1/2 · s−3/2 agreed well with the results of experimental sectioning. Based on this criterion, optimization of the ingot was carried out by decreasing the height-to-diameter ratio and increasing the taper, which successfully eliminated the centreline porosity and further proved the applicability of this criterion.

  20. On translational superfluidity and the Landau criterion for Bose gases in the Gross-Pitaevski limit

    International Nuclear Information System (INIS)

    Wreszinski, Walter F

    2008-01-01

    The two-fluid and Landau criteria for superfluidity are compared for trapped Bose gases. While the two-fluid criterion predicts translational superfluidity, it is suggested, on the basis of the homogeneous Gross-Pitaevski limit, that a necessary part of Landau's criterion, adequate for non-translationally invariant systems, does not hold for trapped Bose gases in the GP limit. As a consequence, if the compressibility is detected to be very large (infinite by experimental standards), the two-fluid criterion is seen to be the relevant one in case the system is a translational superfluid, while the Landau criterion is the relevant one if translational superfluidity is absent. (fast track communication)

  1. Role of optimization criterion in static asymmetric analysis of lumbar spine load.

    Science.gov (United States)

    Daniel, Matej

    2011-10-01

    A common method for load estimation in biomechanics is the inverse dynamics optimization, where the muscle activation pattern is found by minimizing or maximizing the optimization criterion. It has been shown that various optimization criteria predict remarkably similar muscle activation pattern and intra-articular contact forces during leg motion. The aim of this paper is to study the effect of the choice of optimization criterion on L4/L5 loading during static asymmetric loading. Upright standing with weight in one stretched arm was taken as a representative position. Musculoskeletal model of lumbar spine model was created from CT images of Visible Human Project. Several criteria were tested based on the minimization of muscle forces, muscle stresses, and spinal load. All criteria provide the same level of lumbar spine loading (difference is below 25%), except the criterion of minimum lumbar shear force which predicts unrealistically high spinal load and should not be considered further. Estimated spinal load and predicted muscle force activation pattern are in accordance with the intradiscal pressure measurements and EMG measurements. The L4/L5 spine loads 1312 N, 1674 N, and 1993 N were predicted for mass of weight in hand 2, 5, and 8 kg, respectively using criterion of mininum muscle stress cubed. As the optimization criteria do not considerably affect the spinal load, their choice is not critical in further clinical or ergonomic studies and computationally simpler criterion can be used.

  2. Treatment credibility, expectancy, and preference: Prediction of treatment engagement and outcome in a randomized clinical trial of hatha yoga vs. health education as adjunct treatments for depression.

    Science.gov (United States)

    Uebelacker, Lisa A; Weinstock, Lauren M; Battle, Cynthia L; Abrantes, Ana M; Miller, Ivan W

    2018-06-02

    Hatha yoga may be helpful for alleviating depression symptoms. The purpose of this analysis is to determine whether treatment program preference, credibility, or expectancy predict engagement in depression interventions (yoga or a control class) or depression symptom severity over time. This is a secondary analysis of a randomized controlled trial (RCT) of hatha yoga vs. a health education control group for treatment of depression. Depressed participants (n = 122) attended up to 20 classes over a period of 10 weeks, and then completed additional assessments after 3 and 6 months. We assessed treatment preference prior to randomization, and treatment credibility and expectancy after participants attended their first class. Treatment "concordance" indicated that treatment preference matched assigned treatment. Treatment credibility, expectancy, and concordance were not associated with treatment engagement. Treatment expectancy moderated the association between treatment group and depression. Depression severity over time differed by expectancy level for the yoga group but not for the health education group. Controlling for baseline depression, participants in the yoga group with an average or high expectancy for improvement showed lower depression symptoms across the acute intervention and follow-up period than those with a low expectancy for improvement. There was a trend for a similar pattern for credibility. Concordance was not associated with treatment outcome. This is a secondary, post-hoc analysis and should be considered hypothesis-generating. Results suggest that expectancy improves the likelihood of success only for a intervention thought to actively target depression (yoga) and not a control intervention. Copyright © 2018. Published by Elsevier B.V.

  3. A criterion for selecting renewable energy processes

    International Nuclear Information System (INIS)

    Searcy, Erin; Flynn, Peter C.

    2010-01-01

    We propose that minimum incremental cost per unit of greenhouse gas (GHG) reduction, in essence the carbon credit required to economically sustain a renewable energy plant, is the most appropriate social criterion for choosing from a myriad of alternatives. The application of this criterion is illustrated for four processing alternatives for straw/corn stover: production of power by direct combustion and biomass integrated gasification and combined cycle (BIGCC), and production of transportation fuel via lignocellulosic ethanol and Fischer Tropsch (FT) syndiesel. Ethanol requires a lower carbon credit than FT, and direct combustion a lower credit than BIGCC. For comparing processes that make a different form of end use energy, in this study ethanol vs. electrical power via direct combustion, the lowest carbon credit depends on the relative values of the two energy forms. When power is 70$ MW h -1 , ethanol production has a lower required carbon credit at oil prices greater than 600$ t -1 (80$ bbl -1 ). (author)

  4. Stability Criterion for a Finned Spinning Projectile

    OpenAIRE

    S. D. Naik

    2000-01-01

    The state-of-the-art in gun projectile technology has been used for the aerodynamic stabilisation.This approach is acceptable for guided and controlled rockets but the free-flight rockets suffer fromunacceptable dispersion. Sabot projectiles with both spin and fms developed during the last decadeneed careful analysis. In this study, the second method of Liapunov has been used to develop stability criterion for a projectile to be designed with small fins and is made to spin in the flight. This...

  5. Blind equalization with criterion with memory nonlinearity

    Science.gov (United States)

    Chen, Yuanjie; Nikias, Chrysostomos L.; Proakis, John G.

    1992-06-01

    Blind equalization methods usually combat the linear distortion caused by a nonideal channel via a transversal filter, without resorting to the a priori known training sequences. We introduce a new criterion with memory nonlinearity (CRIMNO) for the blind equalization problem. The basic idea of this criterion is to augment the Godard [or constant modulus algorithm (CMA)] cost function with additional terms that penalize the autocorrelations of the equalizer outputs. Several variations of the CRIMNO algorithms are derived, with the variations dependent on (1) whether the empirical averages or the single point estimates are used to approximate the expectations, (2) whether the recent or the delayed equalizer coefficients are used, and (3) whether the weights applied to the autocorrelation terms are fixed or are allowed to adapt. Simulation experiments show that the CRIMNO algorithm, and especially its adaptive weight version, exhibits faster convergence speed than the Godard (or CMA) algorithm. Extensions of the CRIMNO criterion to accommodate the case of correlated inputs to the channel are also presented.

  6. Sequential lineups: shift in criterion or decision strategy?

    Science.gov (United States)

    Gronlund, Scott D

    2004-04-01

    R. C. L. Lindsay and G. L. Wells (1985) argued that a sequential lineup enhanced discriminability because it elicited use of an absolute decision strategy. E. B. Ebbesen and H. D. Flowe (2002) argued that a sequential lineup led witnesses to adopt a more conservative response criterion, thereby affecting bias, not discriminability. Height was encoded as absolute (e.g., 6 ft [1.83 m] tall) or relative (e.g., taller than). If a sequential lineup elicited an absolute decision strategy, the principle of transfer-appropriate processing predicted that performance should be best when height was encoded absolutely. Conversely, if a simultaneous lineup elicited a relative decision strategy, performance should be best when height was encoded relatively. The predicted interaction was observed, providing direct evidence for the decision strategies explanation of what happens when witnesses view a sequential lineup.

  7. Rayleigh Number Criterion for Formation of A-Segregates in Steel Castings and Ingots

    DEFF Research Database (Denmark)

    Rad, M. Torabi; Kotas, Petr; Beckermann, C.

    2013-01-01

    A Rayleigh number-based criterion is developed for predicting the formation of A-segregates in steel castings and ingots. The criterion is calibrated using available experimental data for ingots involving 27 different steel compositions. The critical Rayleigh number above which A-segregates can b......, the primary reason for this over-prediction is persumed to be the presence of a central zone of equiaxed grains in the casting sections. A-segregates do not form when the grain structure is equiaxed. © The Minerals, Metals & Materials Society and ASM International 2013...

  8. Novel global robust stability criterion for neural networks with delay

    International Nuclear Information System (INIS)

    Singh, Vimal

    2009-01-01

    A novel criterion for the global robust stability of Hopfield-type interval neural networks with delay is presented. An example illustrating the improvement of the present criterion over several recently reported criteria is given.

  9. Reactor instrumentation. Definition of the single failure criterion

    International Nuclear Information System (INIS)

    1980-12-01

    The standard defines the single failure criterion which is used in other IEC publications on reactor safety systems. The purpose of the single failure criterion is the assurance of minimum redundancy. (orig./HP) [de

  10. Two novel synchronization criterions for a unified chaotic system

    International Nuclear Information System (INIS)

    Tao Chaohai; Xiong Hongxia; Hu Feng

    2006-01-01

    Two novel synchronization criterions are proposed in this paper. It includes drive-response synchronization and adaptive synchronization schemes. Moreover, these synchronization criterions can be applied to a large class of chaotic systems and are very useful for secure communication

  11. Systems interaction and single failure criterion

    International Nuclear Information System (INIS)

    1981-01-01

    This report documents the results of a six-month study to evaluate the ongoing research programs of the U.S. Nuclear Regulatory Commission (NRC) and U.S. commercial nuclear station owners which address the safety significance of systems interaction and the regulatory adequacy of the single failure criterion. The evaluation of system interactions provided is the initial phase of a more detailed study leading to the development and application of methodology for quantifying the relative safety of operating nuclear plants. (Auth.)

  12. The Goiania accident: release from hospital criterion

    International Nuclear Information System (INIS)

    Falcao, R.C.; Hunt, J.

    1990-01-01

    On the thirteenth of September 1987, a 1357 Ci Cesium source was removed from the 'Instituto de Radiologia de Goiania' - probably two or three days later the source was opened, causing the internal and external contamination of 247 people, and part of the city of Goiania. This paper describes the release from hospital criterion of the contaminated patients, based on radiation protection principles which were developed for this case. The estimate of the biological half-life for cesium is also described. (author) [pt

  13. Early Stop Criterion from the Bootstrap Ensemble

    DEFF Research Database (Denmark)

    Hansen, Lars Kai; Larsen, Jan; Fog, Torben L.

    1997-01-01

    This paper addresses the problem of generalization error estimation in neural networks. A new early stop criterion based on a Bootstrap estimate of the generalization error is suggested. The estimate does not require the network to be trained to the minimum of the cost function, as required...... by other methods based on asymptotic theory. Moreover, in contrast to methods based on cross-validation which require data left out for testing, and thus biasing the estimate, the Bootstrap technique does not have this disadvantage. The potential of the suggested technique is demonstrated on various time...

  14. Satisfying the Einstein–Podolsky–Rosen criterion with massive particles

    Science.gov (United States)

    Peise, J.; Kruse, I.; Lange, K.; Lücke, B.; Pezzè, L.; Arlt, J.; Ertmer, W.; Hammerer, K.; Santos, L.; Smerzi, A.; Klempt, C.

    2015-01-01

    In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of quantum mechanics by devising a quantum state of two massive particles with maximally correlated space and momentum coordinates. The EPR criterion qualifies such continuous-variable entangled states, where a measurement of one subsystem seemingly allows for a prediction of the second subsystem beyond the Heisenberg uncertainty relation. Up to now, continuous-variable EPR correlations have only been created with photons, while the demonstration of such strongly correlated states with massive particles is still outstanding. Here we report on the creation of an EPR-correlated two-mode squeezed state in an ultracold atomic ensemble. The state shows an EPR entanglement parameter of 0.18(3), which is 2.4 s.d. below the threshold 1/4 of the EPR criterion. We also present a full tomographic reconstruction of the underlying many-particle quantum state. The state presents a resource for tests of quantum nonlocality and a wide variety of applications in the field of continuous-variable quantum information and metrology. PMID:26612105

  15. Satisfying the Einstein-Podolsky-Rosen criterion with massive particles.

    Science.gov (United States)

    Peise, J; Kruse, I; Lange, K; Lücke, B; Pezzè, L; Arlt, J; Ertmer, W; Hammerer, K; Santos, L; Smerzi, A; Klempt, C

    2015-11-27

    In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of quantum mechanics by devising a quantum state of two massive particles with maximally correlated space and momentum coordinates. The EPR criterion qualifies such continuous-variable entangled states, where a measurement of one subsystem seemingly allows for a prediction of the second subsystem beyond the Heisenberg uncertainty relation. Up to now, continuous-variable EPR correlations have only been created with photons, while the demonstration of such strongly correlated states with massive particles is still outstanding. Here we report on the creation of an EPR-correlated two-mode squeezed state in an ultracold atomic ensemble. The state shows an EPR entanglement parameter of 0.18(3), which is 2.4 s.d. below the threshold 1/4 of the EPR criterion. We also present a full tomographic reconstruction of the underlying many-particle quantum state. The state presents a resource for tests of quantum nonlocality and a wide variety of applications in the field of continuous-variable quantum information and metrology.

  16. Generalized melting criterion for beam-induced amorphization

    International Nuclear Information System (INIS)

    Lam, N. Q.; Okamoto, Paul R.

    1993-09-01

    Recent studies have shown that the mean-square static atomic displacements provide a generic measure of the enthalpy stored in the lattice in the form of chemical and topological disorder, and that the effect of the displacements on the softening of shear elastic constants is identical to that of heating. This finding lends support to a generalized form of the Lindemann phenomenological melting criterion and leads to a natural interpretion of crystalline-to-amorphous transformations as defect-induced melting of metastable crystals driven beyond a critical state of disorder where the melting temperature falls below the glass-transition temperature. Application of the generalized Lindemann criterion to both the crystalline and amorphous phases indicates that the enthalpies of the two phases become identical when their shear moduli become equal. This thermo-elastic rule provides a basis for predicting the relative susceptibility of compounds to amorphization in terms of their elastic properties as measured by Debye temperatures. The present approach can explain many of the basic findings on beam-induced amorphization of intermetallic compounds as well as amorphous phase formation associated with ion implantation, ion-beam mixing and other solid-state processes

  17. Goldberger-Treiman constraint criterion for hyperon coupling constants

    International Nuclear Information System (INIS)

    General, Ignacio J.; Cotanch, Stephen R.

    2004-01-01

    The generalized Goldberger-Treiman relation is combined with the Dashen-Weinstein sum rule to provide a constraint equation between the g KΣN and g KΛN coupling constants. A comprehensive examination of the published phenomenological and theoretical hyperon couplings has yielded a much smaller set of values, spanning the intervals 0.80≤g KΣN /√(4π)≤2.72 and -3.90≤g KΛN /√(4π)≤-1.84, consistent with this criterion. The broken SU F (3) and Goldberger-Treiman hyperon couplings satisfy the constraint along with predictions from a Taylor series extrapolation using the same momentum variation as exhibited by g πNN

  18. Reviewing Employee Turnover: Focusing on Proximal Withdrawal States and an Expanded Criterion

    Science.gov (United States)

    Hom, Peter W.; Mitchell, Terence R.; Lee, Thomas W.; Griffeth, Rodger W.

    2012-01-01

    We reconceptualize employee turnover to promote researchers' understanding and prediction of why employees quit or stay in employing institutions. A literature review identifies shortcomings with prevailing turnover dimensions. In response, we expand the conceptual domain of the turnover criterion to include multiple types of turnover (notably,…

  19. Discriminant Validity Assessment: Use of Fornell & Larcker criterion versus HTMT Criterion

    Science.gov (United States)

    Hamid, M. R. Ab; Sami, W.; Mohmad Sidek, M. H.

    2017-09-01

    Assessment of discriminant validity is a must in any research that involves latent variables for the prevention of multicollinearity issues. Fornell and Larcker criterion is the most widely used method for this purpose. However, a new method has emerged for establishing the discriminant validity assessment through heterotrait-monotrait (HTMT) ratio of correlations method. Therefore, this article presents the results of discriminant validity assessment using these methods. Data from previous study was used that involved 429 respondents for empirical validation of value-based excellence model in higher education institutions (HEI) in Malaysia. From the analysis, the convergent, divergent and discriminant validity were established and admissible using Fornell and Larcker criterion. However, the discriminant validity is an issue when employing the HTMT criterion. This shows that the latent variables under study faced the issue of multicollinearity and should be looked into for further details. This also implied that the HTMT criterion is a stringent measure that could detect the possible indiscriminant among the latent variables. In conclusion, the instrument which consisted of six latent variables was still lacking in terms of discriminant validity and should be explored further.

  20. Extended equal areas criterion: foundations and applications

    Energy Technology Data Exchange (ETDEWEB)

    Yusheng, Xue [Nanjim Automation Research Institute, Nanjim (China)

    1994-12-31

    The extended equal area criterion (EEAC) provides analytical expressions for ultra fast transient stability assessment, flexible sensitivity analysis, and means to preventive and emergency controls. Its outstanding performances have been demonstrated by thousands upon thousands simulations on more than 50 real power systems and by on-line operation records in an EMS environment of Northeast China Power System since September 1992. However, the researchers have mainly based on heuristics and simulations. This paper lays a theoretical foundation of EEAC and brings to light the mechanism of transient stability. It proves true that the dynamic EEAC furnishes a necessary and sufficient condition for stability of multi machine systems with any detailed models, in the sense of the integration accuracy. This establishes a new platform for further advancing EEAC and better understanding of problems. An overview of EEAC applications in China is also given in this paper. (author) 30 refs.

  1. Application of the single failure criterion

    International Nuclear Information System (INIS)

    1990-01-01

    In order to present further details on the application and interpretation and on the limitations of individual concepts in the NUSS Codes and Safety Guides, a series of Safety Practice publications have been initiated. It is hoped that many Member States will be able to benefit from the experience presented in these books. The present publication will be useful not only to regulators but also to designers and could be particularly helpful in the interpretation of cases which fall on the borderline between the two areas. It should assist in clarifying, by way of examples, many of the concepts and implementation methods. It also describes some of the limitations involved. The book addresses a specialized topic and it is recommended that it be used together with the other books in the Safety Series. During the development of this publication the actual practices of all countries with major reactor programmes has been taken into account. An interpretation of the relevant text of the Design Code is given in the light of these national practices. The criterion is put into perspective with the general reliability requirements in which it is also embedded in the Design Code. Its relation to common cause and other multiple failure cases and also to the temporary disengagement of components in systems important to safety is clarified. Its use and its limitations are thus explained in the context of reliability targets for systems performance. The guidance provided applies to all reactor systems and would be applicable even to systems not in nuclear power plants. But since this publication was developed to give an interpretation of a specific requirement of the Design Code, the broader applicability is not explicitly claimed. The Design Code lists three cases for which compliance with the criterion may not be justified. The present publication assists in the more precise and practical identification of those cases. 9 figs, 1 tab

  2. Predicting adolescent problematic online game use from teacher autonomy support, basic psychological needs satisfaction, and school engagement: a 2-year longitudinal study.

    Science.gov (United States)

    Yu, Chengfu; Li, Xian; Zhang, Wei

    2015-04-01

    Problematic online game use (POGU) has become a serious global public health concern among adolescents. However, its influencing factors and mediating mechanisms remain largely unknown. This study provides the first longitudinal design to test stage-environment fit theory empirically in POGU. A total of 356 Chinese students reported on teacher autonomy support, basic psychological needs satisfaction, school engagement, and POGU in the autumn of their 7th-9th grade years. Path analyses supported the proposed pathway: 7th grade teacher autonomy support increased 8th grade basic psychological needs satisfaction, which in turn increased 9th grade school engagement, which ultimately decreased 9th grade POGU. Furthermore, 7th grade teacher autonomy support directly increased 9th grade school engagement, which in turn decreased 9th grade POGU. These findings suggest that teacher autonomy support is an important protective predictor of adolescent POGU, and basic psychological needs satisfaction and school engagement are the primary mediators in this association.

  3. Accuracy of a selection criterion for glass forming ability in the Ni–Nb–Zr system

    International Nuclear Information System (INIS)

    Déo, L.P.; Oliveira, M.F. de

    2014-01-01

    Highlights: • We applied a selection in the Ni–Nb–Zr system to find alloys with high GFA. • We used the thermal parameter γ m to evaluate the GFA of alloys. • The correlation between the γ m parameter and R c in the studied system is poor. • The effect of oxygen impurity reduced dramatically the GFA of alloys. • Unknown intermetallic compounds reduced the accuracy of the criterion. - Abstract: Several theories have been developed and applied in metallic systems in order to find the best stoichiometries with high glass forming ability; however there is no universal theory to predict the glass forming ability in metallic systems. Recently a selection criterion was applied in the Zr–Ni–Cu system and it was found some correlation between experimental and theoretical data. This criterion correlates critical cooling rate for glass formation with topological instability of stable crystalline structures; average work function difference and average electron density difference among the constituent elements of the alloy. In the present work, this criterion was applied in the Ni–Nb–Zr system. It was investigated the influence of factors not considered in the calculation and on the accuracy of the criterion, such as unknown intermetallic compounds and oxygen contamination. Bulk amorphous specimens were produced by injection casting. The amorphous nature was analyzed by X-ray diffraction and differential scanning calorimetry; oxygen contamination was quantified by the inert gas fusion method

  4. A Path-Independent Forming Limit Criterion for Stamping Simulations

    International Nuclear Information System (INIS)

    Zhu Xinhai; Chappuis, Laurent; Xia, Z. Cedric

    2005-01-01

    Forming Limit Diagram (FLD) has been proved to be a powerful tool for assessing necking failures in sheet metal forming analysis for majority of stamping operations over the last three decades. However, experimental evidence and theoretical analysis suggest that its applications are limited to linear or almost linear strain paths during its deformation history. Abrupt changes or even gradual deviations from linear strain-paths will shift forming limit curves from their original values, a situation that occurs in vast majority of sequential stamping operations such as where the drawing process is followed by flanging and re-strike processes. Various forming limit models have been put forward recently to provide remedies for the problem, noticeably stress-based and strain gradient-based forming limit criteria. This study presents an alternative path-independent forming limit criterion. Instead of traditional Forming Limit Diagrams (FLD) which are constructed in terms of major - minor principal strains throughout deformation history, the new criterion defines a critical effective strain ε-bar* as the limit strain for necking, and it is shown that ε-bar* can be expressed as a function of current strain rate state and material work hardening properties, without the need of explicitly considering strain-path effects. It is given by ε-bar* = f(β, k, n) where β = (dε 2 /dε 1 ) at current deformation state, and k and n are material strain hardening parameters if a power law is assumed. The analysis is built upon previous work by Storen and Rice [1975] and Zhu et al [2002] with the incorporation of anisotropic yield models such as Hill'48 for quadratic orthotropic yield and Hill'79 for non-quadratic orthotropic yield. Effects of anisotropic parameters such as R-values and exponent n-values on necking are investigated in detail for a variety of strain paths. Results predicted according to current analysis are compared against experimental data gathered from literature

  5. Direct numerical simulations of non-premixed ethylene-air flames: Local flame extinction criterion

    KAUST Repository

    Lecoustre, Vivien R.

    2014-11-01

    Direct Numerical Simulations (DNS) of ethylene/air diffusion flame extinctions in decaying two-dimensional turbulence were performed. A Damköhler-number-based flame extinction criterion as provided by classical large activation energy asymptotic (AEA) theory is assessed for its validity in predicting flame extinction and compared to one based on Chemical Explosive Mode Analysis (CEMA) of the detailed chemistry. The DNS code solves compressible flow conservation equations using high order finite difference and explicit time integration schemes. The ethylene/air chemistry is simulated with a reduced mechanism that is generated based on the directed relation graph (DRG) based methods along with stiffness removal. The numerical configuration is an ethylene fuel strip embedded in ambient air and exposed to a prescribed decaying turbulent flow field. The emphasis of this study is on the several flame extinction events observed in contrived parametric simulations. A modified viscosity and changing pressure (MVCP) scheme was adopted in order to artificially manipulate the probability of flame extinction. Using MVCP, pressure was changed from the baseline case of 1 atm to 0.1 and 10 atm. In the high pressure MVCP case, the simulated flame is extinction-free, whereas in the low pressure MVCP case, the simulated flame features frequent extinction events and is close to global extinction. Results show that, despite its relative simplicity and provided that the global flame activation temperature is correctly calibrated, the AEA-based flame extinction criterion can accurately predict the simulated flame extinction events. It is also found that the AEA-based criterion provides predictions of flame extinction that are consistent with those provided by a CEMA-based criterion. This study supports the validity of a simple Damköhler-number-based criterion to predict flame extinction in engineering-level CFD models. © 2014 The Combustion Institute.

  6. Unitary Evolution as a Uniqueness Criterion

    Science.gov (United States)

    Cortez, J.; Mena Marugán, G. A.; Olmedo, J.; Velhinho, J. M.

    2015-01-01

    It is well known that the process of quantizing field theories is plagued with ambiguities. First, there is ambiguity in the choice of basic variables describing the system. Second, once a choice of field variables has been made, there is ambiguity concerning the selection of a quantum representation of the corresponding canonical commutation relations. The natural strategy to remove these ambiguities is to demand positivity of energy and to invoke symmetries, namely by requiring that classical symmetries become unitarily implemented in the quantum realm. The success of this strategy depends, however, on the existence of a sufficiently large group of symmetries, usually including time-translation invariance. These criteria are therefore generally insufficient in non-stationary situations, as is typical for free fields in curved spacetimes. Recently, the criterion of unitary implementation of the dynamics has been proposed in order to select a unique quantization in the context of manifestly non-stationary systems. Specifically, the unitarity criterion, together with the requirement of invariance under spatial symmetries, has been successfully employed to remove the ambiguities in the quantization of linearly polarized Gowdy models as well as in the quantization of a scalar field with time varying mass, propagating in a static background whose spatial topology is either of a d-sphere (with d = 1, 2, 3) or a three torus. Following Ref. 3, we will see here that the symmetry and unitarity criteria allows for a complete removal of the ambiguities in the quantization of scalar fields propagating in static spacetimes with compact spatial sections, obeying field equations with an explicitly time-dependent mass, of the form ddot φ - Δ φ + s(t)φ = 0 . These results apply in particular to free fields in spacetimes which, like e.g. in the closed FRW models, are conformal to a static spacetime, by means of an exclusively time-dependent conformal factor. In fact, in such

  7. Geophysicists' views about public engagement

    Science.gov (United States)

    Besley, J. C.; Dudo, A.; Yuan, S.

    2016-12-01

    The proposed talk would present the results of 2016 survey of American Geophysical Union members (n = 2040) about public engagement. This survey took place as part of a broader, NSF funded, study of engagement views across eight different U.S.-based scientific societies. The presentation would include data about geophysicists' past engagement behavior and willingness to engage alongside data about engagement attitudes, perceived norms (i.e. beliefs about whether peers engage and value engagement), and perceived efficacy (i.e., scientists' beliefs about their own communication skills and the impact of engagement). The presentation would also include results that describe scientists' overall goals for engagement (e.g., increasing support for specific policy positions, changing citizen behavior, etc.), as well as their communication-specific objectives (e.g., increasing knowledge, increase excitement, etc.). All of the results would be put in the context of equivalent results from scientists from seven other societies across a variety of fields, including chemistry, biology, and the social sciences. Three themes that would be emphasized in the presentation include (1) the fact that there are substantial commonalities in engagement views across scientific fields, (2) the important role that perceived engagement skill (efficacy) appears to play in predicting engagement willingness, and (3) a lack of evidence that scientists are thinking about engagement in strategic ways. Strategic engagement, in this regard, would involve setting clear goals and then choosing activities that the social science of science communication suggests might allow one to achieve those goals. The presentation would conclude with thoughts about what might be done to improve the effectiveness of science communication training.

  8. Situating Engagement

    DEFF Research Database (Denmark)

    Korn, Matthias

    Our mobile phone is with us at all times. Habitually, we pick it up in the morning and carry it around on our daily routes and routines. Increasingly, we use it to locate ourselves and the things and people around us. With ubiquitous computing, technology is moving into the very fabric of our....... First, situationally appropriate forms of engagement that align well with citizens’ own conceptions are necessary in order to provide relevance and meaning of issues in the moment. Second, situated engagement requires a technological setup which facilitates the co-location of people, place...... with sophisticated prototypes in the wild. It proposes walkshops as a technique for collaborative exploration within actual outdoor environments and the use of field trials as part of an iterative design process in order to look ahead toward use practices that are still in the making....

  9. A criterion for heated pipe design by linear electric resistances

    International Nuclear Information System (INIS)

    Bloch, M.; Cruz, J.R.B.

    1984-01-01

    A criterion for linear eletrical elements instalation on horizontal tubes is obtainned in this work. This criterion is based upon the calculation of the thermal stresses caused by the non uniform temperature distribution in the tube cross section. The finite difference method and the SAP IV computer code are both used in the calculations. The criterion is applied to the thermal circuits of the IEN which has tube diameter varying from φ 1/2 in till φ 8 in. (author) [pt

  10. A new self-report inventory of dyslexia for students: criterion and construct validity.

    Science.gov (United States)

    Tamboer, Peter; Vorst, Harrie C M

    2015-02-01

    The validity of a Dutch self-report inventory of dyslexia was ascertained in two samples of students. Six biographical questions, 20 general language statements and 56 specific language statements were based on dyslexia as a multi-dimensional deficit. Dyslexia and non-dyslexia were assessed with two criteria: identification with test results (Sample 1) and classification using biographical information (both samples). Using discriminant analyses, these criteria were predicted with various groups of statements. All together, 11 discriminant functions were used to estimate classification accuracy of the inventory. In Sample 1, 15 statements predicted the test criterion with classification accuracy of 98%, and 18 statements predicted the biographical criterion with classification accuracy of 97%. In Sample 2, 16 statements predicted the biographical criterion with classification accuracy of 94%. Estimations of positive and negative predictive value were 89% and 99%. Items of various discriminant functions were factor analysed to find characteristic difficulties of students with dyslexia, resulting in a five-factor structure in Sample 1 and a four-factor structure in Sample 2. Answer bias was investigated with measures of internal consistency reliability. Less than 20 self-report items are sufficient to accurately classify students with and without dyslexia. This supports the usefulness of self-assessment of dyslexia as a valid alternative to diagnostic test batteries. Copyright © 2015 John Wiley & Sons, Ltd.

  11. LSSVM-Based Rock Failure Criterion and Its Application in Numerical Simulation

    Directory of Open Access Journals (Sweden)

    Changxing Zhu

    2015-01-01

    Full Text Available A rock failure criterion is very important for the prediction of the failure of rocks or rock masses in rock mechanics and engineering. Least squares support vector machines (LSSVM are a powerful tool for addressing complex nonlinear problems. This paper describes a LSSVM-based rock failure criterion for analyzing the deformation of a circular tunnel under different in situ stresses without assuming a function form. First, LSSVM was used to represent the nonlinear relationship between the mechanical properties of rock and the failure behavior of the rock in order to construct a rock failure criterion based on experimental data. Then, this was used in a hypothetical numerical analysis of a circular tunnel to analyze the mechanical behavior of the rock mass surrounding the tunnel. The Mohr-Coulomb and Hoek-Brown failure criteria were also used to analyze the same case, and the results were compared; these clearly indicate that LSSVM can be used to establish a rock failure criterion and to predict the failure of a rock mass during excavation of a circular tunnel.

  12. Predicting the Academic Achievement of First-Year, Pre-Service Teachers: The Role of Engagement, Motivation, ATAR, and Emotional Intelligence

    Science.gov (United States)

    Wurf, Gerald; Croft-Piggin, Lindy

    2015-01-01

    Australian universities are enrolling a larger and more diverse undergraduate student population. Counter to this trend, several states have developed plans to restrict entrance into the teaching profession. This study investigates the role of engagement, motivation, Australian Tertiary Admission Rank (ATAR), and emotional intelligence in the…

  13. Suboptimal Criterion Learning in Static and Dynamic Environments.

    Directory of Open Access Journals (Sweden)

    Elyse H Norton

    2017-01-01

    Full Text Available Humans often make decisions based on uncertain sensory information. Signal detection theory (SDT describes detection and discrimination decisions as a comparison of stimulus "strength" to a fixed decision criterion. However, recent research suggests that current responses depend on the recent history of stimuli and previous responses, suggesting that the decision criterion is updated trial-by-trial. The mechanisms underpinning criterion setting remain unknown. Here, we examine how observers learn to set a decision criterion in an orientation-discrimination task under both static and dynamic conditions. To investigate mechanisms underlying trial-by-trial criterion placement, we introduce a novel task in which participants explicitly set the criterion, and compare it to a more traditional discrimination task, allowing us to model this explicit indication of criterion dynamics. In each task, stimuli were ellipses with principal orientations drawn from two categories: Gaussian distributions with different means and equal variance. In the covert-criterion task, observers categorized a displayed ellipse. In the overt-criterion task, observers adjusted the orientation of a line that served as the discrimination criterion for a subsequently presented ellipse. We compared performance to the ideal Bayesian learner and several suboptimal models that varied in both computational and memory demands. Under static and dynamic conditions, we found that, in both tasks, observers used suboptimal learning rules. In most conditions, a model in which the recent history of past samples determines a belief about category means fit the data best for most observers and on average. Our results reveal dynamic adjustment of discrimination criterion, even after prolonged training, and indicate how decision criteria are updated over time.

  14. Engaging Siblingships

    DEFF Research Database (Denmark)

    Gulløv, Eva; Palludan, Charlotte; Winther, Ida Wentzel

    2015-01-01

    Inspired by sociological and anthropological family studies, our point of departure is that there is neither a given nor an unequivocal prototype of sibling relationships. On the basis of qualitative interviews, dialogues and filmed observations of everyday life, we investigate how children...... and young people in contemporary Denmark engage emotionally in sibling relationships. It emerges that siblingships inevitably involve frictions in various forms. In the article, we analyse the impact frictions have on social relations and discuss how such dynamics in sibling relationships both reflect...

  15. The Concept of Performance Levels in Criterion-Referenced Assessment.

    Science.gov (United States)

    Hewitson, Mal

    The concept of performance levels in criterion-referenced assessment is explored by applying the idea to different types of tests commonly used in schools, mastery tests (including diagnostic tests) and achievement tests. In mastery tests, a threshold performance standard must be established for each criterion. Attainment of this threshold…

  16. Mediating role of work engagement in the relationship between job resources and personal resources with turnover intention among female nurses.

    Science.gov (United States)

    Shahpouri, Samira; Namdari, Kourosh; Abedi, Ahmad

    2016-05-01

    One of the latest models proposed with regard to work engagement is the detailed model put forward by Bakker and Demerouti (2007). The present study aims at investigating the effect of job resources and personal resources on turnover intention with the mediator role of work engagement among female nurses at Isfahan Alzahra Hospital. In the current study, job and personal resources were considered as the predictors of job turnover and work engagement was considered as the mediator variable among predictive and criterion variables. The data of the present study were collected from 208 female nurses who were selected by systematic random sampling. As for the analysis of the collected data, structural equations model, normal distribution method, and Bootstrap method in Macro, Preacher and Hayes, (2004) program were deployed. The findings showed that the personal resources affect the turnover intention both directly and indirectly (through work engagement); however, job resources are just associated with turnover intention with the mediating role of work engagement. The results of the study have important implications for organizations' managers about improving work engagement. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Modified Schur-Cohn Criterion for Stability of Delayed Systems

    Directory of Open Access Journals (Sweden)

    Juan Ignacio Mulero-Martínez

    2015-01-01

    Full Text Available A modified Schur-Cohn criterion for time-delay linear time-invariant systems is derived. The classical Schur-Cohn criterion has two main drawbacks; namely, (i the dimension of the Schur-Cohn matrix generates some round-off errors eventually resulting in a polynomial of s with erroneous coefficients and (ii imaginary roots are very hard to detect when numerical errors creep in. In contrast to the classical Schur-Cohn criterion an alternative approach is proposed in this paper which is based on the application of triangular matrices over a polynomial ring in a similar way as in the Jury test of stability for discrete systems. The advantages of the proposed approach are that it halves the dimension of the polynomial and it only requires seeking real roots, making this modified criterion comparable to the Rekasius substitution criterion.

  18. [GSH fermentation process modeling using entropy-criterion based RBF neural network model].

    Science.gov (United States)

    Tan, Zuoping; Wang, Shitong; Deng, Zhaohong; Du, Guocheng

    2008-05-01

    The prediction accuracy and generalization of GSH fermentation process modeling are often deteriorated by noise existing in the corresponding experimental data. In order to avoid this problem, we present a novel RBF neural network modeling approach based on entropy criterion. It considers the whole distribution structure of the training data set in the parameter learning process compared with the traditional MSE-criterion based parameter learning, and thus effectively avoids the weak generalization and over-learning. Then the proposed approach is applied to the GSH fermentation process modeling. Our results demonstrate that this proposed method has better prediction accuracy, generalization and robustness such that it offers a potential application merit for the GSH fermentation process modeling.

  19. Failure Criterion for Brick Masonry: A Micro-Mechanics Approach

    Directory of Open Access Journals (Sweden)

    Kawa Marek

    2015-02-01

    Full Text Available The paper deals with the formulation of failure criterion for an in-plane loaded masonry. Using micro-mechanics approach the strength estimation for masonry microstructure with constituents obeying the Drucker-Prager criterion is determined numerically. The procedure invokes lower bound analysis: for assumed stress fields constructed within masonry periodic cell critical load is obtained as a solution of constrained optimization problem. The analysis is carried out for many different loading conditions at different orientations of bed joints. The performance of the approach is verified against solutions obtained for corresponding layered and block microstructures, which provides the upper and lower strength bounds for masonry microstructure, respectively. Subsequently, a phenomenological anisotropic strength criterion for masonry microstructure is proposed. The criterion has a form of conjunction of Jaeger critical plane condition and Tsai-Wu criterion. The model proposed is identified based on the fitting of numerical results obtained from the microstructural analysis. Identified criterion is then verified against results obtained for different loading orientations. It appears that strength of masonry microstructure can be satisfactorily described by the criterion proposed.

  20. The AP diameter of the pelvis: a new criterion for continence in the exstrophy complex?

    International Nuclear Information System (INIS)

    Ait-Ameur, A.; Kalifa, G.; Adamsbaum, C.; Wakim, A.; Dubousset, J.

    2001-01-01

    Reconstructive surgery of bladder exstrophy remains a challenge. By using CT of the pelvis, we suggest a new pre- and post-operative investigative procedure to define the AP diameter (APD) as a predictive criterion for continence in this anomaly. Patients and methods: Three axial CT slices were selected in nine children with exstrophy who had undergone neonatal reconstructive surgery. The three levels selected were the first sacral plate, the mid acetabular plane and the superior pubic spine. We used combined slices to measure: circle APD = distance between the first sacral vertebra and the pubic symphysis. circle Pubic diastasis (PD) circle Three angles defined on the transverse plane of the first sacral vertebra - iliac wing angle, sacropubic angle and acetabular version. In exstrophy, the angles demonstrate opening of the iliac wings and the pubic ramus, and acetabular retroversion compared to controls. Comparisons between controls, continent and incontinent patients reveal that in continent patients, APD increases with growth and seems to be a predictive criterion for continence, independent of diastasis of the pubic symphysis. We believe that CT of the pelvis with measurements of the APD should be performed in all neonates with bladder exstrophy before reconstructive surgery and for better understanding of the malformation. The APD seems to be predictive and may be a major criterion for continence, independent of PD. (orig.)

  1. Criterion for testing multiparticle negative-partial-transpose entanglement

    International Nuclear Information System (INIS)

    Zeng, B.; Zhou, D.L.; Zhang, P.; Xu, Z.; You, L.

    2003-01-01

    We revisit the criterion of multiparticle entanglement based on the overlaps of a given quantum state ρ with maximally entangled states. For a system of m particles, each with N distinct states, we prove that ρ is m-particle negative partial transpose entangled, if there exists a maximally entangled state vertical bar MES>, such that >1/N. While this sufficiency condition is weaker than the Peres-Horodecki criterion in all cases, it applies to multi-particle systems, and becomes especially useful when the number of particles (m) is large. We also consider the converse of this criterion and illustrate its invalidity with counter examples

  2. Industry Software Trustworthiness Criterion Research Based on Business Trustworthiness

    Science.gov (United States)

    Zhang, Jin; Liu, Jun-fei; Jiao, Hai-xing; Shen, Yi; Liu, Shu-yuan

    To industry software Trustworthiness problem, an idea aiming to business to construct industry software trustworthiness criterion is proposed. Based on the triangle model of "trustworthy grade definition-trustworthy evidence model-trustworthy evaluating", the idea of business trustworthiness is incarnated from different aspects of trustworthy triangle model for special industry software, power producing management system (PPMS). Business trustworthiness is the center in the constructed industry trustworthy software criterion. Fusing the international standard and industry rules, the constructed trustworthy criterion strengthens the maneuverability and reliability. Quantitive evaluating method makes the evaluating results be intuitionistic and comparable.

  3. Criterion of damage beginning: experimental identification for laminate composite

    International Nuclear Information System (INIS)

    Thiebaud, F.; Perreux, D.; Varchon, D.; Lebras, J.

    1996-01-01

    The aim of this study is to propose a criterion of damage beginning for laminate composite. The materials is a glass-epoxy laminate [+55 deg.,-55 deg.[ n performed by winding filament process. First of all a description of the damage is performed and allows to define a damage variable. Thanks to the potential of free energy, an associated variable is defined. The damage criterion is written by using this last one. The parameter of the criterion is identified using mechanical and acoustical methods. The result is compared and exhibit a good agreement. (authors). 13 refs., 5 figs

  4. "I can do it": does confidence and perceived ability in learning new ICT skills predict pre-service health professionals' attitude towards engaging in e-healthcare?

    Science.gov (United States)

    Lam, Mary K; Nguyen, Melanie; Lowe, Robyn; Nagarajan, Srivalli V; Lincoln, Michelle

    2014-01-01

    There are many factors affecting health professionals' willingness to engage in e-health. One of these factors is whether health professionals perceive themselves to be able to learn new skills, and have the confidence in mastering these new Information and Communication Technology (ICT) skills. This study examined how health students' confidence and perceived ability for learning new ICT skills affect their attitude towards engaging in e-health. A survey was conducted to explore students' attitude towards using e-health and their perceived self-efficacy and confidence to learn new ICT skills. Multiple regression analysis was used to examine the relationship between confidence and self-efficacy, and attitude towards engaging in e-health controlling for participants' age, gender, and prior IT learning experience. The three scales measuring attitude, confidence and self-efficacy showed good internal consistency with respective Cronbach's Alpha scores of 0.835, 0.761 and 0.762. Multiple regression analysis showed a significant relationship between confidence, self-efficacy and prior IT learning experiences with attitude towards e-health after adjusting for the effect of each other (F3,350=17.20,p<0.001). Self-efficacy and confidence in learning new ICT skills together with previous ICT training either at or outside their university studies are significant factors associated with students' attitude towards using e-health. Enhancing students' level of self-efficacy in learning new ICT skills may be the key to the success of implementation of e-health initiatives.

  5. A study on the instability criterion for the stratified flow in horizontal pipe at cocurrent flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chang Kyung [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1997-12-31

    This paper presents a theoretical approach of the instability criterion from stratified to nonstratified flow in horizontal pipe at cocurrent flow conditions. The new theoretical instability criterion for the stratified and nonstratified flow transition in horizontal pipe has been developed by hyperbolic equations in two-phase flow. Critical flow condition criterion and onset of slugging at cocurrent flow condition correspond to zero and imaginary characteristics which occur when the hyperbolicity of a stratified two-phase flow is broken, respectively. Through comparison between results predicted by the present flow is broken, respectively. Through comparison between results predicted by the present theory and the Kukita et al. [1] experimental data of pipes, it is shown that they are in good agreement with data. 4 refs., 2 figs. (Author)

  6. A study on the instability criterion for the stratified flow in horizontal pipe at cocurrent flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chang Kyung [Korea Electric Power Research Institute, Taejon (Korea, Republic of)

    1998-12-31

    This paper presents a theoretical approach of the instability criterion from stratified to nonstratified flow in horizontal pipe at cocurrent flow conditions. The new theoretical instability criterion for the stratified and nonstratified flow transition in horizontal pipe has been developed by hyperbolic equations in two-phase flow. Critical flow condition criterion and onset of slugging at cocurrent flow condition correspond to zero and imaginary characteristics which occur when the hyperbolicity of a stratified two-phase flow is broken, respectively. Through comparison between results predicted by the present flow is broken, respectively. Through comparison between results predicted by the present theory and the Kukita et al. [1] experimental data of pipes, it is shown that they are in good agreement with data. 4 refs., 2 figs. (Author)

  7. Importance biasing quality criterion based on contribution response theory

    International Nuclear Information System (INIS)

    Borisov, N.M.; Panin, M.P.

    2001-01-01

    The report proposes a visual criterion of importance biasing both of forward and adjoint simulation. The similarity of contribution Monte Carlo and importance biasing random collision event distribution is proved. The conservation of total number of random trajectory crossings of surfaces, which separate the source and the detector is proposed as importance biasing quality criterion. The use of this criterion is demonstrated on the example of forward vs. adjoint importance biasing in gamma ray deep penetration problem. The larger amount of published data on forward field characteristics than on adjoint leads to the more accurate approximation of adjoint importance function in comparison to forward, for it adjoint importance simulation is more effective than forward. The proposed criterion indicates it visually, showing the most uniform distribution of random trajectory crossing events for the most effective importance biasing parameters and pointing to the direction of tuning importance biasing parameters. (orig.)

  8. A multipole acceptability criterion for electronic structure theory

    International Nuclear Information System (INIS)

    Schwegler, E.; Challacombe, M.; Head-Gordon, M.

    1998-01-01

    Accurate and computationally inexpensive estimates of multipole expansion errors are crucial to the success of several fast electronic structure methods. In this paper, a new nonempirical multipole acceptability criterion is described that is directly applicable to expansions of high order moments. Several model calculations typical of electronic structure theory are presented to demonstrate its performance. For cases involving small translation distances, accuracies are increased by up to five orders of magnitude over an empirical criterion. The new multipole acceptance criterion is on average within an order of magnitude of the exact expansion error. Use of the multipole acceptance criterion in hierarchical multipole based methods as well as in traditional electronic structure methods is discussed. copyright 1998 American Institute of Physics

  9. Bayesian Information Criterion as an Alternative way of Statistical Inference

    Directory of Open Access Journals (Sweden)

    Nadejda Yu. Gubanova

    2012-05-01

    Full Text Available The article treats Bayesian information criterion as an alternative to traditional methods of statistical inference, based on NHST. The comparison of ANOVA and BIC results for psychological experiment is discussed.

  10. Angular criterion for distinguishing between Fraunhofer and Fresnel diffraction

    International Nuclear Information System (INIS)

    Medina, Francisco F.; Garcia-Sucerquia, Jorge; Castaneda, Roman; Matteucci, Giorgio

    2003-03-01

    The distinction between Fresnel and Fraunhofer diffraction is a crucial condition for the accurate analysis of diffracting structures. In this paper we propose a criterion based on the angle subtended by the first zero of the diffraction pattern from the center of the diffracting aperture. The determination of the zero of the diffraction pattern is the crucial point for assuring the precision of the criterion. It mainly depends on the dynamical range of the detector. Therefore, the applicability of adequate thresholds for different detector types is discussed. The criterion is also generalized by expressing it in terms of the number of Fresnel zones delimited by the aperture. Simulations are reported for illustrating the feasibility of the criterion. (author)

  11. Stochastic Learning and the Intuitive Criterion in Simple Signaling Games

    DEFF Research Database (Denmark)

    Sloth, Birgitte; Whitta-Jacobsen, Hans Jørgen

    A stochastic learning process for signaling games with two types, two signals, and two responses gives rise to equilibrium selection which is in remarkable accordance with the selection obtained by the intuitive criterion......A stochastic learning process for signaling games with two types, two signals, and two responses gives rise to equilibrium selection which is in remarkable accordance with the selection obtained by the intuitive criterion...

  12. A Criterion to Identify Maximally Entangled Four-Qubit State

    International Nuclear Information System (INIS)

    Zha Xinwei; Song Haiyang; Feng Feng

    2011-01-01

    Paolo Facchi, et al. [Phys. Rev. A 77 (2008) 060304(R)] presented a maximally multipartite entangled state (MMES). Here, we give a criterion for the identification of maximally entangled four-qubit states. Using this criterion, we not only identify some existing maximally entangled four-qubit states in the literature, but also find several new maximally entangled four-qubit states as well. (general)

  13. Self-Adjointness Criterion for Operators in Fock Spaces

    International Nuclear Information System (INIS)

    Falconi, Marco

    2015-01-01

    In this paper we provide a criterion of essential self-adjointness for operators in the tensor product of a separable Hilbert space and a Fock space. The class of operators we consider may contain a self-adjoint part, a part that preserves the number of Fock space particles and a non-diagonal part that is at most quadratic with respect to the creation and annihilation operators. The hypotheses of the criterion are satisfied in several interesting applications

  14. Decision criterion dynamics in animals performing an auditory detection task.

    Directory of Open Access Journals (Sweden)

    Robert W Mill

    Full Text Available Classical signal detection theory attributes bias in perceptual decisions to a threshold criterion, against which sensory excitation is compared. The optimal criterion setting depends on the signal level, which may vary over time, and about which the subject is naïve. Consequently, the subject must optimise its threshold by responding appropriately to feedback. Here a series of experiments was conducted, and a computational model applied, to determine how the decision bias of the ferret in an auditory signal detection task tracks changes in the stimulus level. The time scales of criterion dynamics were investigated by means of a yes-no signal-in-noise detection task, in which trials were grouped into blocks that alternately contained easy- and hard-to-detect signals. The responses of the ferrets implied both long- and short-term criterion dynamics. The animals exhibited a bias in favour of responding "yes" during blocks of harder trials, and vice versa. Moreover, the outcome of each single trial had a strong influence on the decision at the next trial. We demonstrate that the single-trial and block-level changes in bias are a manifestation of the same criterion update policy by fitting a model, in which the criterion is shifted by fixed amounts according to the outcome of the previous trial and decays strongly towards a resting value. The apparent block-level stabilisation of bias arises as the probabilities of outcomes and shifts on single trials mutually interact to establish equilibrium. To gain an intuition into how stable criterion distributions arise from specific parameter sets we develop a Markov model which accounts for the dynamic effects of criterion shifts. Our approach provides a framework for investigating the dynamics of decisions at different timescales in other species (e.g., humans and in other psychological domains (e.g., vision, memory.

  15. Optimal design of constant-stress accelerated degradation tests using the M-optimality criterion

    International Nuclear Information System (INIS)

    Wang, Han; Zhao, Yu; Ma, Xiaobing; Wang, Hongyu

    2017-01-01

    In this paper, we propose the M-optimality criterion for designing constant-stress accelerated degradation tests (ADTs). The newly proposed criterion concentrates on the degradation mechanism equivalence rather than evaluation precision or prediction accuracy which is usually considered in traditional optimization criteria. Subject to the constraints of total sample number, test termination time as well as the stress region, an optimum constant-stress ADT plan is derived by determining the combination of stress levels and the number of samples allocated to each stress level, when the degradation path comes from inverse Gaussian (IG) process model with covariates and random effects. A numerical example is presented to verify the robustness of our proposed optimum plan and compare its efficiency with other test plans. Results show that, with a slightly relaxed requirement of evaluation precision and prediction accuracy, our proposed optimum plan reduces the dispersion of the estimated acceleration factor between the usage stress level and a higher accelerated stress level, which makes an important contribution to reliability demonstration and assessment tests. - Highlights: • We establish the necessary conditions for degradation mechanism equivalence of ADTs. • We propose the M-optimality criterion for designing constant-stress ADT plans. • The M-optimality plan reduces the dispersion of the estimated accelerated factors. • An electrical connector with its stress relaxation data is used for illustration.

  16. Wavelength selection in injection-driven Hele-Shaw flows: A maximum amplitude criterion

    Science.gov (United States)

    Dias, Eduardo; Miranda, Jose

    2013-11-01

    As in most interfacial flow problems, the standard theoretical procedure to establish wavelength selection in the viscous fingering instability is to maximize the linear growth rate. However, there are important discrepancies between previous theoretical predictions and existing experimental data. In this work we perform a linear stability analysis of the radial Hele-Shaw flow system that takes into account the combined action of viscous normal stresses and wetting effects. Most importantly, we introduce an alternative selection criterion for which the selected wavelength is determined by the maximum of the interfacial perturbation amplitude. The effectiveness of such a criterion is substantiated by the significantly improved agreement between theory and experiments. We thank CNPq (Brazilian Sponsor) for financial support.

  17. Application of a new criterion for assessing the susceptibility to internal erosion

    Energy Technology Data Exchange (ETDEWEB)

    Li, M.; Garner, S.J. [BC Hydro, Burnaby, BC (Canada); Fannin, R.J. [British Columbia Univ., Vancouver, BC (Canada)

    2009-07-01

    Occasionally, internal erosion can occur in internally unstable soils that are subject to seepage flow. This paper presented a modification to the Kenney-Lau criterion for assessing susceptibility to internal erosion in widely-graded cohesionless soils. The original Kenney-Lau criterion and the newly-proposed Li-Fannin criteria were both used to evaluate the grading stability of filter and core materials from two zoned earthfill dams in British Columbia. Using a statistical approach, the criteria were applied to construction data to account for the many gradation curves available within the specification envelope for materials used in construction. The paper discussed the implications of the findings within the context of laboratory permeameter tests on the same soils, and also based on a sinkhole incident at one of the dams. It was concluded that the Kenney-Lau method appears to be less conservative for predicting the internal instability of widely graded materials. 16 refs., 5 figs.

  18. Criterion for vortex breakdown on shock wave and streamwise vortex interactions.

    Science.gov (United States)

    Hiejima, Toshihiko

    2014-05-01

    The interactions between supersonic streamwise vortices and oblique shock waves are theoretically and numerically investigated by three-dimensional (3D) Navier-Stokes equations. Based on the two inequalities, a criterion for shock-induced breakdown of the streamwise vortex is proposed. The simple breakdown condition depends on the Mach number, the swirl number, the velocity deficit, and the shock angle. According to the proposed criterion, the breakdown region expands as the Mach number increases. In numerical simulations, vortex breakdown appeared under conditions of multiple pressure increases and the helicity disappeared behind the oblique shock wave along the line of the vortex center. The numerical results are consistent with the predicted breakdown condition at Mach numbers 2.0 and 3.0. This study also found that the axial velocity deficit is important for classifying the breakdown configuration.

  19. Ethical leadership: meta-analytic evidence of criterion-related and incremental validity.

    Science.gov (United States)

    Ng, Thomas W H; Feldman, Daniel C

    2015-05-01

    This study examines the criterion-related and incremental validity of ethical leadership (EL) with meta-analytic data. Across 101 samples published over the last 15 years (N = 29,620), we observed that EL demonstrated acceptable criterion-related validity with variables that tap followers' job attitudes, job performance, and evaluations of their leaders. Further, followers' trust in the leader mediated the relationships of EL with job attitudes and performance. In terms of incremental validity, we found that EL significantly, albeit weakly in some cases, predicted task performance, citizenship behavior, and counterproductive work behavior-even after controlling for the effects of such variables as transformational leadership, use of contingent rewards, management by exception, interactional fairness, and destructive leadership. The article concludes with a discussion of ways to strengthen the incremental validity of EL. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  20. A criterion for the onset of slugging in horizontal stratified air-water countercurrent flow

    International Nuclear Information System (INIS)

    Chun, Moon-Hyun; Lee, Byung-Ryung; Kim, Yang-Seok

    1995-01-01

    This paper presents an experimental and theoretical investigation of wave height and transition criterion from wavy to slug flow in horizontal air-water countercurrent stratified flow conditions. A theoretical formula for the wave height in a stratified wavy flow regime has been developed using the concept of total energy balance over a wave crest to consider the shear stress acting on the interface of two fluids. From the limiting condition of the formula for the wave height, a necessary criterion for transition from a stratified wavy flow to a slug flow has been derived. A series of experiments have been conducted changing the non-dimensional water depth and the flow rates of air in a horizontal pipe and a duct. Comparisons between the measured data and the predictions of the present theory show that the agreement is within ±8%

  1. A criterion for the onset of slugging in horizontal stratified air-water countercurrent flow

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Moon-Hyun; Lee, Byung-Ryung; Kim, Yang-Seok [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)] [and others

    1995-09-01

    This paper presents an experimental and theoretical investigation of wave height and transition criterion from wavy to slug flow in horizontal air-water countercurrent stratified flow conditions. A theoretical formula for the wave height in a stratified wavy flow regime has been developed using the concept of total energy balance over a wave crest to consider the shear stress acting on the interface of two fluids. From the limiting condition of the formula for the wave height, a necessary criterion for transition from a stratified wavy flow to a slug flow has been derived. A series of experiments have been conducted changing the non-dimensional water depth and the flow rates of air in a horizontal pipe and a duct. Comparisons between the measured data and the predictions of the present theory show that the agreement is within {plus_minus}8%.

  2. Ductile failure analysis of API X65 pipes with notch-type defects using a local fracture criterion

    International Nuclear Information System (INIS)

    Oh, Chang-Kyun; Kim, Yun-Jae; Baek, Jong-Hyun; Kim, Young-Pyo; Kim, Woo-Sik

    2007-01-01

    A local failure criterion for API X65 steel is applied to predict ductile failure of full-scale API X65 pipes with simulated corrosion and gouge defects under internal pressure. The local failure criterion is the stress-modified fracture strain as a function of the stress triaxiality (defined by the ratio of the hydrostatic stress to the effective stress). Based on detailed finite element (FE) analyses with the proposed local failure criterion, burst pressures of defective pipes are estimated and compared with experimental data. For pipes with simulated corrosion defects, FE analysis with the proposed local fracture criterion indicates that predicted failure takes place after the defective pipes attain maximum loads for all cases, possibly due to the fact that the material has sufficient ductility. For pipes with simulated gouge defects, on the other hand, it is found that predicted failure takes place before global instability, and the predicted burst pressures are in good agreement with experimental data, providing confidence in the present approach

  3. Socially responsible investment engagement

    NARCIS (Netherlands)

    Goessling, T.; Buijter, Bas; Freeman, R.E.; Kujala, J.; Sachs, S.

    2017-01-01

    This study explores engagement in socially responsible investment (SRI) processes. More specifically, it researches the impact of shareholder salience on the success of engagement activities. The research question asks: What is the relationship between shareholder salience and engagement effort

  4. Electricity Consumption Forecasting Scheme via Improved LSSVM with Maximum Correntropy Criterion

    Directory of Open Access Journals (Sweden)

    Jiandong Duan

    2018-02-01

    Full Text Available In recent years, with the deepening of China’s electricity sales side reform and electricity market opening up gradually, the forecasting of electricity consumption (FoEC becomes an extremely important technique for the electricity market. At present, how to forecast the electricity accurately and make an evaluation of results scientifically are still key research topics. In this paper, we propose a novel prediction scheme based on the least-square support vector machine (LSSVM model with a maximum correntropy criterion (MCC to forecast the electricity consumption (EC. Firstly, the electricity characteristics of various industries are analyzed to determine the factors that mainly affect the changes in electricity, such as the gross domestic product (GDP, temperature, and so on. Secondly, according to the statistics of the status quo of the small sample data, the LSSVM model is employed as the prediction model. In order to optimize the parameters of the LSSVM model, we further use the local similarity function MCC as the evaluation criterion. Thirdly, we employ the K-fold cross-validation and grid searching methods to improve the learning ability. In the experiments, we have used the EC data of Shaanxi Province in China to evaluate the proposed prediction scheme, and the results show that the proposed prediction scheme outperforms the method based on the traditional LSSVM model.

  5. The precautionary principle as a rational decision criterion

    International Nuclear Information System (INIS)

    Hovi, Jon

    2001-12-01

    The paper asks if the precautionary principle may be seen as a rational decision criterion. Six main questions are discussed. 1. Does the principle basically represent a particular set of political options or is it a genuine decision criterion? 2. If it is the latter, can it be reduced to any of the existing criteria for decision making under uncertainty? 3. In what kinds of situation is the principle applicable? 4. What is the relation between the precautionary principle and other principles for environmental regulation? 5. How plausible is the principle's claim that the burden of proof should be reversed? 6. Do the proponents of environmental regulation carry no burden of proof at all? A main conclusion is that, for now at least, the principle contains too many unclear elements to satisfy the requirements of precision and consistency that should reasonably be satisfied by a rational decision criterion. (author)

  6. Study on the quantitative rod internal pressure design criterion

    International Nuclear Information System (INIS)

    Kim, Kyu Tae; Kim, Oh Hwan; Han, Hee Tak

    1991-01-01

    The current rod internal pressure criterion permits fuel rods to operate with internal pressures in excess of system pressure only if internal overpressure does not cause the diametral gap enlargement. In this study, the generic allowable internal gas pressure not violating this criterion is estimated as a function of rod power. The results show that the generic allowable internal gas pressure decreases linearly with the increase of rod power. Application of the generic allowable internal gas pressure for the rod internal pressure design criterion will result in the simplication of the current design procedure for checking the diametral gap enlargement caused by internal overpressure because according to the current design procedure the cladding creepout rate should be compared with the fuel swelling rate at each axial node at each time step whenever internal pressure exceeds the system pressure. (Author)

  7. Development of failure criterion for Kevlar-epoxy fabric laminates

    Science.gov (United States)

    Tennyson, R. C.; Elliott, W. G.

    1984-01-01

    The development of the tensor polynomial failure criterion for composite laminate analysis is discussed. In particular, emphasis is given to the fabrication and testing of Kevlar-49 fabric (Style 285)/Narmco 5208 Epoxy. The quadratic-failure criterion with F(12)=0 provides accurate estimates of failure stresses for the Kevlar/Epoxy investigated. The cubic failure criterion was re-cast into an operationally easier form, providing the engineer with design curves that can be applied to laminates fabricated from unidirectional prepregs. In the form presented no interaction strength tests are required, although recourse to the quadratic model and the principal strength parameters is necessary. However, insufficient test data exists at present to generalize this approach for all undirectional prepregs and its use must be restricted to the generic materials investigated to-date.

  8. A Joint Optimization Criterion for Blind DS-CDMA Detection

    Directory of Open Access Journals (Sweden)

    Sergio A. Cruces-Alvarez

    2007-01-01

    Full Text Available This paper addresses the problem of the blind detection of a desired user in an asynchronous DS-CDMA communications system with multipath propagation channels. Starting from the inverse filter criterion introduced by Tugnait and Li in 2001, we propose to tackle the problem in the context of the blind signal extraction methods for ICA. In order to improve the performance of the detector, we present a criterion based on the joint optimization of several higher-order statistics of the outputs. An algorithm that optimizes the proposed criterion is described, and its improved performance and robustness with respect to the near-far problem are corroborated through simulations. Additionally, a simulation using measurements on a real software-radio platform at 5 GHz has also been performed.

  9. A Joint Optimization Criterion for Blind DS-CDMA Detection

    Science.gov (United States)

    Durán-Díaz, Iván; Cruces-Alvarez, Sergio A.

    2006-12-01

    This paper addresses the problem of the blind detection of a desired user in an asynchronous DS-CDMA communications system with multipath propagation channels. Starting from the inverse filter criterion introduced by Tugnait and Li in 2001, we propose to tackle the problem in the context of the blind signal extraction methods for ICA. In order to improve the performance of the detector, we present a criterion based on the joint optimization of several higher-order statistics of the outputs. An algorithm that optimizes the proposed criterion is described, and its improved performance and robustness with respect to the near-far problem are corroborated through simulations. Additionally, a simulation using measurements on a real software-radio platform at 5 GHz has also been performed.

  10. The role of word choice and criterion on intentional memory.

    Science.gov (United States)

    Toyota, Hiroshi

    2015-02-01

    The relationship between the criterion for choosing and the self-choice effects (greater recall in a self-choice compared to a forced-choice condition) on intentional memory was examined. Thirty-three female nursing school volunteers were administered 24 word pairs in a 2 × 2 design to assess the influence of motivation upon free recall. When word pairs were presented to participants, they were asked to choose a word to-be-remembered, either in a self-choice condition or a forced-choice condition. Words chosen by the participants were recalled more often than those chosen by the experimenter (forced choice). Thus, the self-choice effect was greater for words chosen with a self-reference criterion compared to a metamemory criterion, supporting the integration hypothesis as the origin of the self-choice effect.

  11. SOCIO-PSYCHOLOGICAL CRITERIONS OF FAMILY LIFESTYLE TYPOLOGY

    Directory of Open Access Journals (Sweden)

    Yekaterina Anatolievna Yumkina

    2015-02-01

    Full Text Available The purpose of this article is to present socio-psychological criterions of family lifestyle typology, which were found during theoretical modelling and empirical research work. It is important in fundamental and practical aspects. St-Petersburg students (n = 116, from 19 to 21 years old were examined by special questionnaire «Family relationship and home» (Kunitsi-na V.N., Yumkina Ye.A., 2012 which measures different aspects of family lifestyle. We also used complex of methods that gave us information about personal values, self-rating and parent-child relationships. Dates were divided into six groups according to three main criterions of family lifestyle typology: social environment of family life, family activity, and family interpersonal relationships. There were found statistically significant differences between pairs of group from every criterions. The results can be useful in spheres dealing with family crisis, family development, family traditions etc.

  12. Judging Criterion of Controlled Structures with Closely Spaced Natural Frequencies

    International Nuclear Information System (INIS)

    Xie Faxiang; Sun Limin

    2010-01-01

    The structures with closely spaced natural frequencies widely exist in civil engineering; however, the judging criterion of the density of closely spaced frequencies is in dispute. This paper suggests a judging criterion for structures with closely spaced natural frequencies based on the analysis on a controlled 2-DOF structure. The analysis results indicate that the optimal control gain of the structure with velocity feedback is dependent on the frequency density parameter of structure and the maximum attainable additional modal damping ratio is 1.72 times of the frequency density parameter when state feedback is applied. Based on a brief review on the previous researches, a judging criterion related the minimum frequency density parameter and the required mode damping ratio was proposed.

  13. Probabilistic interpretation of the reduction criterion for entanglement

    International Nuclear Information System (INIS)

    Zhang, Zhengmin; Luo, Shunlong

    2007-01-01

    Inspired by the idea of conditional probabilities, we introduce a variant of conditional density operators. But unlike the conditional probabilities which are bounded by 1, the conditional density operators may have eigenvalues exceeding 1 for entangled states. This has the consequence that although any bivariate classical probability distribution has a natural separable decomposition in terms of conditional probabilities, we do not have a quantum analogue of this separable decomposition in general. The 'nonclassical' eigenvalues of conditional density operators are indications of entanglement. The resulting separability criterion turns out to be equivalent to the reduction criterion introduced by Horodecki [Phys. Rev. A 59, 4206 (1999)] and Cerf et al. [Phys. Rev. A 60, 898 (1999)]. This supplies an intuitive probabilistic interpretation for the reduction criterion. The conditional density operators are also used to define a form of quantum conditional entropy which provides an alternative mechanism to reveal quantum discord

  14. A ductile fracture criterion with Zener-Hollomon parameter of pure molybdenum sheet in thermal forming

    Directory of Open Access Journals (Sweden)

    Wang Chu

    2015-01-01

    Full Text Available Formability of pure molybdenum in thermal forming process has been greatly improved, but it is still hard to avoid the generation of rupture and other quality defects. In this paper, a ductile fracture criterion of pure molybdenum sheet in thermal forming was established by considering the plastic deformation capacity of material and stress states, which can be used to describe fracture behaviour and critical rupture prediction of pure molybdenum sheet during hot forming process. Based on the isothermal uniaxial tensile tests which performed at 993 to 1143 K with strain rate range from 0.0005 to 0.2 s−1, the material parameters are calculated by the combination method of experiment with FEsimulation. Based on the observation, new fracture criteria can be expressed as a function of Zener-Hollomon parameter. The critical fracture value that calculated by Oyane-Sato criterion increases with increasing temperature and decreasing strain rate. The ductile fracture criterion with Zener-Hollomon parameter of pure molybdenum in thermal forming is proposed.

  15. Criterion-based laparoscopic training reduces total training time

    OpenAIRE

    Brinkman, Willem M.; Buzink, Sonja N.; Alevizos, Leonidas; de Hingh, Ignace H. J. T.; Jakimowicz, Jack J.

    2011-01-01

    Introduction The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns (no laparoscopic experience) practiced on two basic tasks on the Simbionix LAP Mentor virtual-reality (VR) simulator: ‘clipping and grasping’ and ‘cutting’. Group C (criterion-based) (N...

  16. Criterion of cleavage crack propagation and arrest in a nuclear PWR vessel steel

    International Nuclear Information System (INIS)

    Bousquet, Amaury

    2013-01-01

    The purpose of this PhD thesis is to understand physical mechanisms of cleavage crack propagation and arrest in the 16MND5 PWR vessel steel and to propose a robust predicting model based on a brittle fracture experimental campaign of finely instrumented laboratory specimens associated with numerical computations. First, experiments were carried out on thin CT25 specimens at five temperatures (-150 C, -125 C, -100 C, -7 C, -50 C). Two kinds of crack path, straight or branching path, have been observed. To characterize crack propagation and to measure crack speed, a high-speed framing camera system was used, combined with the development of an experimental protocol which allowed to observe CT surface without icing inside the thermal chamber and on the specimen. The framing camera (520 000 fps) has allowed to have a very accurate estimation of crack speed on the complete ligament of CT (∼ 25 mm). Besides, to analyse experiments and to study the impact of viscosity on the mechanical response around the crack tip, the elastic-viscoplastic behavior of the ferritic steel has been studied up to a strain rate of 104 s -1 for the tested temperatures.The extended Finite Element Method (X-FEM) was used in CAST3M FE software to model crack propagation. Numerical computations combine a local non linear dynamic approach with a RKR type fracture stress criterion to a characteristic distance. The work carried out has confirmed the form of the criterion proposed by Prabel at -125 C, and has identified the dependencies of the criterion on temperature and strain rate. From numerical analyzes in 2D and 3D, a multi-temperature fracture stress criterion, increasing function of the strain rate, was proposed. Predictive modeling were used to confirm the identified criterion on two specimen geometries (CT and compressive ring) in mode I at different temperatures. SEM observations and 3D analyzes made with optical microscope showed that the fracture mechanism was the cleavage associated

  17. Study on criterion for leak before break assessment of pressure pipes

    International Nuclear Information System (INIS)

    Yang Linjuan

    2009-01-01

    Based on the elastoplastic fracture mechanics, this paper established the expression formulas of limit buckling pressure P u on the ligament of axial and circumferential surface cracks and the initial pressure for the through cracks P c . A new Leak Before Break (LBB) assessment criterion was put forward to predict the failure mode of pressure pipes, i.e., when P u is less than P c , the pipe will leak; when P u is equal to or larger than P c , the pipe will break, which is verified by the test data reported in literatures. (authors)

  18. A Criterion-Referenced Approach to Student Ratings of Instruction

    Science.gov (United States)

    Meyer, J. Patrick; Doromal, Justin B.; Wei, Xiaoxin; Zhu, Shi

    2017-01-01

    We developed a criterion-referenced student rating of instruction (SRI) to facilitate formative assessment of teaching. It involves four dimensions of teaching quality that are grounded in current instructional design principles: Organization and structure, Assessment and feedback, Personal interactions, and Academic rigor. Using item response…

  19. An extended geometric criterion for chaos in the Dicke model

    International Nuclear Information System (INIS)

    Li Jiangdan; Zhang Suying

    2010-01-01

    We extend HBLSL's (Horwitz, Ben Zion, Lewkowicz, Schiffer and Levitan) new Riemannian geometric criterion for chaotic motion to Hamiltonian systems of weak coupling of potential and momenta by defining the 'mean unstable ratio'. We discuss the Dicke model of an unstable Hamiltonian system in detail and show that our results are in good agreement with that of the computation of Lyapunov characteristic exponents.

  20. Short-Cut Estimators of Criterion-Referenced Test Consistency.

    Science.gov (United States)

    Brown, James Dean

    1990-01-01

    Presents simplified methods for deriving estimates of the consistency of criterion-referenced, English-as-a-Second-Language tests, including (1) the threshold loss agreement approach using agreement or kappa coefficients, (2) the squared-error loss agreement approach using the phi(lambda) dependability approach, and (3) the domain score…

  1. Decision models for use with criterion-referenced tests

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1980-01-01

    The problem of mastery decisions and optimizing cutoff scores on criterion-referenced tests is considered. This problem can be formalized as an (empirical) Bayes problem with decisions rules of a monotone shape. Next, the derivation of optimal cutoff scores for threshold, linear, and normal ogive

  2. Integral criterion for selecting nonlinear crystals for frequency conversion

    International Nuclear Information System (INIS)

    Grechin, Sergei G

    2009-01-01

    An integral criterion, which takes into account all parameters determining the conversion efficiency, is offered for selecting nonlinear crystals for frequency conversion. The angular phase-matching width is shown to be related to the beam walk-off angle. (nonlinear optical phenomena)

  3. Criterion-based laparoscopic training reduces total training time

    NARCIS (Netherlands)

    Brinkman, W.M.; Buzink, S.N.; Alevizos, L.; De Hingh, I.H.J.T.; Jakimowicz, J.J.

    2011-01-01

    The benefits of criterion-based laparoscopic training over time-oriented training are unclear. The purpose of this study is to compare these types of training based on training outcome and time efficiency. Methods During four training sessions within 1 week (one session per day) 34 medical interns

  4. Electronics. Criterion-Referenced Test (CRT) Item Bank.

    Science.gov (United States)

    Davis, Diane, Ed.

    This document contains 519 criterion-referenced multiple choice and true or false test items for a course in electronics. The test item bank is designed to work with both the Vocational Instructional Management System (VIMS) and the Vocational Administrative Management System (VAMS) in Missouri. The items are grouped into 15 units covering the…

  5. Prioritising transport infrastructure projects: towards a multi-criterion ...

    African Journals Online (AJOL)

    Kirstam

    multi-criterion analysis (MCA), partial equilibrium analysis, project appraisal ... In the case of transport infrastructure projects, though, this is no mean ... vehicle ownership and mileage-based depreciation (an improved road network and/ .... urban, rural or regional development initiatives – they typically include one or more.

  6. Multidimensional adaptive testing with a minimum error-variance criterion

    NARCIS (Netherlands)

    van der Linden, Willem J.

    1997-01-01

    The case of adaptive testing under a multidimensional logistic response model is addressed. An adaptive algorithm is proposed that minimizes the (asymptotic) variance of the maximum-likelihood (ML) estimator of a linear combination of abilities of interest. The item selection criterion is a simple

  7. Slope stability analysis using limit equilibrium method in nonlinear criterion.

    Science.gov (United States)

    Lin, Hang; Zhong, Wenwen; Xiong, Wei; Tang, Wenyu

    2014-01-01

    In slope stability analysis, the limit equilibrium method is usually used to calculate the safety factor of slope based on Mohr-Coulomb criterion. However, Mohr-Coulomb criterion is restricted to the description of rock mass. To overcome its shortcomings, this paper combined Hoek-Brown criterion and limit equilibrium method and proposed an equation for calculating the safety factor of slope with limit equilibrium method in Hoek-Brown criterion through equivalent cohesive strength and the friction angle. Moreover, this paper investigates the impact of Hoek-Brown parameters on the safety factor of slope, which reveals that there is linear relation between equivalent cohesive strength and weakening factor D. However, there are nonlinear relations between equivalent cohesive strength and Geological Strength Index (GSI), the uniaxial compressive strength of intact rock σ ci , and the parameter of intact rock m i . There is nonlinear relation between the friction angle and all Hoek-Brown parameters. With the increase of D, the safety factor of slope F decreases linearly; with the increase of GSI, F increases nonlinearly; when σ ci is relatively small, the relation between F and σ ci is nonlinear, but when σ ci is relatively large, the relation is linear; with the increase of m i , F decreases first and then increases.

  8. Numerical and Experimental Validation of a New Damage Initiation Criterion

    NARCIS (Netherlands)

    Sadhinoch, M.; Atzema, E.H.; Perdahcioglu, E.S.; Van Den Boogaard, A.H.

    2017-01-01

    Most commercial finite element software packages, like Abaqus, have a built-in coupled damage model where a damage evolution needs to be defined in terms of a single fracture energy value for all stress states. The Johnson-Cook criterion has been modified to be Lode parameter dependent and this

  9. Signal Detection with Criterion Noise: Applications to Recognition Memory

    Science.gov (United States)

    Benjamin, Aaron S.; Diaz, Michael; Wee, Serena

    2009-01-01

    A tacit but fundamental assumption of the theory of signal detection is that criterion placement is a noise-free process. This article challenges that assumption on theoretical and empirical grounds and presents the noisy decision theory of signal detection (ND-TSD). Generalized equations for the isosensitivity function and for measures of…

  10. Criterion III: Maintenance of rangeland productive capacity [Chapter 4

    Science.gov (United States)

    G. R. Evans; R. A. Washmgton-Allen; R. D. Child; J. E. Mitchell; B. R. Bobowskl; R. V. Loper; B. H. Allen-Diaz; D. W. Thompson; G. R. Welling; T. B. Reuwsaat

    2010-01-01

    Maintenance of rangeland productive capacity is one of five criteria established by the Sustainable Rangelands Roundtable (SRR) to monitor and assess rangeland sustainable management. Within this criterion, six indicators were developed through the Delphi Process and the expert opinions of academicians, rangeland scientists, rangeland management agency personnel, non-...

  11. Criterion of Semi-Markov Dependent Risk Model

    Institute of Scientific and Technical Information of China (English)

    Xiao Yun MO; Xiang Qun YANG

    2014-01-01

    A rigorous definition of semi-Markov dependent risk model is given. This model is a generalization of the Markov dependent risk model. A criterion and necessary conditions of semi-Markov dependent risk model are obtained. The results clarify relations between elements among semi-Markov dependent risk model more clear and are applicable for Markov dependent risk model.

  12. An Elementary Proof of a Criterion for Linear Disjointness

    Science.gov (United States)

    Dobbs, David E.

    2013-01-01

    An elementary proof using matrix theory is given for the following criterion: if "F"/"K" and "L"/"K" are field extensions, with "F" and "L" both contained in a common extension field, then "F" and "L" are linearly disjoint over "K" if (and only if) some…

  13. Utilization of Durability Criterion to Develop Automotive Components

    DEFF Research Database (Denmark)

    Ricardo, Luiz Carlos Hernandes

    2010-01-01

    Today the automotive companies must reduce the time to development of new products with improvement in performance, durability and low cost reductions where possible. To achieve this goal the carmakers need to improve the design criterion of car systems like body, chassis and suspension component...

  14. Botanical Criterions of Quchan Baharkish pastureland in Khorasan ...

    African Journals Online (AJOL)

    ADOWIE PERE

    Botanical Criterions of Quchan Baharkish pastureland in Khorasan Razavi Province,. Iran. *1SAEED, JAHEDI POUR 2ALIREZA, KOOCHEKI 3MEHDI, NASSIRI. MAHALLATI 4PARVIZ REZVANI MOGHADDAM. 1Department of Agroecology and Plant Breeding, Ferdowsi. University of Mashhad International Campus, ...

  15. Satisfying the Einstein-Podolsky-Rosen criterion with massive particles

    DEFF Research Database (Denmark)

    Peise, Jan; Kruse, I.; Lange, K.

    2016-01-01

    In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of quantum mechanics by devising a quantum state of two massive particles with maximally correlated space and momentum coordinates. The EPR criterion qualifies such continuous-variable entangled states, as shown successfully...

  16. Ductile failure analysis of defective API X65 pipes based on stress-modified fracture strain criterion

    International Nuclear Information System (INIS)

    Oh, Chang Kyun; Kim, Yun Jae; Baek, Jong Hyun; Kim, Young Pyo; Kim, Woo Sik

    2006-01-01

    A local failure criterion for the API X65 steel is applied to predict ductile failure of full-scale API X65 pipes with simulated corrosion and gouge defects under internal pressure. The local failure criterion is the stress-modified fracture strain for the API X65 steel as a function of the stress triaxiality (defined by the ratio of the hydrostatic stress to the effective stress). Based on detailed FE analyses with the proposed local failure criteria, burst pressures of defective pipes are estimated and compared with experimental data. The predicted burst pressures are in good agreement with experimental data. Noting that an assessment equation against the gouge defect is not yet available, parametric study is performed, from which a simple equation is proposed to predict burst pressure for API X65 pipes with gouge defects

  17. Effective Social Media Engagement for Nonprofits: What Matters?

    Directory of Open Access Journals (Sweden)

    Julia L Carboni

    2015-03-01

    Full Text Available We employ public management relationship theory to examine how nonprofits can effectively engage social media stakeholders in two-way communication. Though many nonprofit organizations have a social media presence, there is variance in how well organizations use social media to engage stakeholders. Simply having a social media presence is not enough to engage stakeholders.  We examine Facebook posts of a stratified random sample of youth development organizations to determine what predicts stakeholder engagement. We find the type of Facebook post is a significant predictor of stakeholder engagement.  Longer posts also significantly predict increased stakeholder engagement.  At the organizational level, having many posts is a significant negative predictor of stakeholder engagement, indicating that users may feel bombarded and are less likely to engage.  Increased organizational spending on advertising as a proportion of total budget is positively associated with stakeholder engagement

  18. Applicability of the Modified Ritchie-Knott-Rice Failure Criterion to Examine the Feasibility of Miniaturized Charpy Type SE(B Specimens

    Directory of Open Access Journals (Sweden)

    Toshiyuki Meshii

    2016-01-01

    Full Text Available This paper examined whether the modified Ritchie-Knott-Rice (RKR failure criterion can be applied to examine the feasibility of miniaturized Charpy type SE(B specimens of thickness-to-width ratio B/W=1. The modified RKR failure criterion considered in this paper is the (4δt,σ22c criterion which predicts the onset of cleavage fracture when the midplane crack-opening stress measured at a distance equal to four times the crack-tip opening displacement, denoted as σ22d, exceeds a critical stress σ22c. Specimens with B values of 25, 10, 3, and 2 mm (denoted as 25t, 10t, 3t, and 2t specimens, resp. manufactured with 0.55% carbon steel were tested at 20°C. The results showed that the modified RKR criterion could appropriately predict the occurrence of cleavage fracture accompanied by negligibly small stable crack extension (denoted as KJc fracture naturally for the 25t and 10t specimens. The modified RKR criterion could also predict that KJc fracture does not occur for the 2t specimen. The σ22c obtained from specimens for the 25t and 10t specimens exhibited only a small difference, indicating that the Jc obtained from the 10t specimens can be used to predict the Jc that will be obtained with the 25t specimens.

  19. Jeans' criterion and nonextensive velocity distribution function in kinetic theory

    International Nuclear Information System (INIS)

    Du Jiulin

    2004-01-01

    The effect of nonextensivity of self-gravitating systems on the Jeans' criterion for gravitational instability is studied in the framework of Tsallis statistics. The nonextensivity is introduced in the Jeans problem by a generalized q-nonextensive velocity distribution function through the equation of state of ideal gas in nonextensive kinetic theory. A new Jeans' criterion is deduced with a factor √(2/(5-3q)) that, however, differs from that one in [Astron. Astrophys. 396 (2002) 309] and new results of gravitational instability are analyzed for the nonextensive parameter q. An understanding of physical meaning of q and a possible seismic observation to find astronomical evidence for a value of q different from unity are also discussed

  20. Logical and Decisive Combining Criterion for Binary Group Decision Making

    Directory of Open Access Journals (Sweden)

    Ivan Vrana

    2010-04-01

    Full Text Available A new combining criterion, the Multiplicative Proportional Deviative Influence (MPDI is presented for combining or aggregating multi-expert numerical judgments in Yes-or-No type ill-structured group decision making situations. This newly proposed criterion performs well in comparison with the widely used aggregation means: the Arithmetic Mean (AM, and Geometric Mean (GM, especially in better reflecting the degree of agreement between criteria levels or numerical experts’ judgments. The MPDI can be considered as another class of combining criteria that make effect of the degree of agreement among multiple numerical judgments. The MPDI is applicable in integrating several collaborative or synergistic decision making systems through combining final numerical decision outputs. A discussion and generalization of the proposed MPDI is discussed withnumerical example.

  1. Satisfying the Einstein-Podolsky-Rosen criterion with massive particles

    Science.gov (United States)

    Peise, J.; Kruse, I.; Lange, K.; Lücke, B.; Pezzè, L.; Arlt, J.; Ertmer, W.; Hammerer, K.; Santos, L.; Smerzi, A.; Klempt, C.

    2016-03-01

    In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of quantum mechanics by devising a quantum state of two massive particles with maximally correlated space and momentum coordinates. The EPR criterion qualifies such continuous-variable entangled states, as shown successfully with light fields. Here, we report on the production of massive particles which meet the EPR criterion for continuous phase/amplitude variables. The created quantum state of ultracold atoms shows an EPR parameter of 0.18(3), which is 2.4 standard deviations below the threshold of 1/4. Our state presents a resource for tests of quantum nonlocality with massive particles and a wide variety of applications in the field of continuous-variable quantum information and metrology.

  2. A Generalized Evolution Criterion in Nonequilibrium Convective Systems

    Science.gov (United States)

    Ichiyanagi, Masakazu; Nisizima, Kunisuke

    1989-04-01

    A general evolution criterion, applicable to transport processes such as the conduction of heat and mass diffusion, is obtained as a direct version of the Le Chatelier-Braun principle for stationary states. The present theory is not based on any radical departure from the conventional one. The generalized theory is made determinate by proposing the balance equations for extensive thermodynamic variables which will reflect the character of convective systems under the assumption of local equilibrium. As a consequence of the introduction of source terms in the balance equations, there appear additional terms in the expression of the local entropy production, which are bilinear in terms of the intensive variables and the sources. In the present paper, we show that we can construct a dissipation function for such general cases, in which the premises of the Glansdorff-Prigogine theory are accumulated. The new dissipation function permits us to formulate a generalized evolution criterion for convective systems.

  3. The Mercier Criterion in Reversed Shear Tokamak Plasmas

    International Nuclear Information System (INIS)

    Kessel, C.; Chance, M.S.; Jardin, S.C.

    1999-01-01

    A recent numerical study has found that, contrary to conventional theoretical and experimental expectations, reversed shear plasmas are unstable primarily because the term proportional to the shear in the Mercier criterion is destabilizing. In the present study, the role of the magnetic shear, both local and global, is examined for various tokamak configurations with monotonic and non-monotonic safety factor profiles. The enhancement of the local shear due to the outward shift of the magnetic axis suggests that the latter are less susceptible to interchanges. Furthermore, by regrouping the terms in the criterion, the V'' term when differentiated instead with respect to the toroidal flux, is shown to absorb the dominant shear term. No Mercier instability is found for similar profiles as in the previous study

  4. Establishment of an equivalence acceptance criterion for accelerated stability studies.

    Science.gov (United States)

    Burdick, Richard K; Sidor, Leslie

    2013-01-01

    In this article, the use of statistical equivalence testing for providing evidence of process comparability in an accelerated stability study is advocated over the use of a test of differences. The objective of such a study is to demonstrate comparability by showing that the stability profiles under nonrecommended storage conditions of two processes are equivalent. Because it is difficult at accelerated conditions to find a direct link to product specifications, and hence product safety and efficacy, an equivalence acceptance criterion is proposed that is based on the statistical concept of effect size. As with all statistical tests of equivalence, it is important to collect input from appropriate subject-matter experts when defining the acceptance criterion.

  5. What Is Student Engagement?

    Science.gov (United States)

    Groccia, James E.

    2018-01-01

    This chapter reviews the history and various definitions of student engagement and proposes a multidimensional model from which one can develop a variety of engagement opportunities that lead to a rich and challenging higher education experience.

  6. A convenient accuracy criterion for time domain FE-calculations

    DEFF Research Database (Denmark)

    Jensen, Morten Skaarup

    1997-01-01

    An accuracy criterion that is well suited to tome domain finite element (FE) calculations is presented. It is then used to develop a method for selecting time steps and element meshes that produce accurate results without significantly overburderning the computer. Use of this method is illustrated...... with a simple example, where comparison with an analytical solution shows that results are sufficiently accurate, which is not always the case with more primitive mthods for determining the discretisation....

  7. On Feller's criterion for the law of the iterated logarithm

    Directory of Open Access Journals (Sweden)

    Deli Li

    1994-01-01

    Full Text Available Combining Feller's criterion with a non-uniform estimate result in the context of the Central Limit Theorem for partial sums of independent random variables, we obtain several results on the Law of the Iterated Logarithm. Two of these results refine corresponding results of Wittmann (1985 and Egorov (1971. In addition, these results are compared with the corresponding results of Teicher (1974, Tomkins (1983 and Tomkins (1990

  8. Statistical criterion for Bubbly-slug flow transition

    Energy Technology Data Exchange (ETDEWEB)

    Zigler, J; Elias, E [Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Mechanical Engineering

    1996-12-01

    The investigation of flow pattern transitions is still an interesting problem in the research of multiphase Row. It has been studied theoretically, and experimental confirmation of the models has been found by many investigators. The present paper deals with a statistical approach to bubbly-slug transitions in a vertical upward two phase flow and a new transition criterion is deduced from experimental data (authors).

  9. On the upper bound in the Bohm sheath criterion

    Energy Technology Data Exchange (ETDEWEB)

    Kotelnikov, I. A., E-mail: I.A.Kotelnikov@inp.nsk.su; Skovorodin, D. I., E-mail: D.I.Skovorodin@inp.nsk.su [Russian Academy of Sciences, Budker Institute of Nuclear Physics, Siberian Branch (Russian Federation)

    2016-02-15

    The question is discussed about the existence of an upper bound in the Bohm sheath criterion, according to which the Debye sheath at the interface between plasma and a negatively charged electrode is stable only if the ion flow velocity in plasma exceeds the ion sound velocity. It is stated that, with an exception of some artificial ionization models, the Bohm sheath criterion is satisfied as an equality at the lower bound and the ion flow velocity is equal to the speed of sound. In the one-dimensional theory, a supersonic flow appears in an unrealistic model of a localized ion source the size of which is less than the Debye length; however, supersonic flows seem to be possible in the two- and three-dimensional cases. In the available numerical codes used to simulate charged particle sources with a plasma emitter, the presence of the upper bound in the Bohm sheath criterion is not supposed; however, the correspondence with experimental data is usually achieved if the ion flow velocity in plasma is close to the ion sound velocity.

  10. Some properties of the computable cross-norm criterion for separability

    International Nuclear Information System (INIS)

    Rudolph, Oliver

    2003-01-01

    The computable cross-norm (CCN) criterion is a powerful analytical and computable separability criterion for bipartite quantum states, which is also known to systematically detect bound entanglement. In certain aspects this criterion complements the well-known Peres positive partial transpose (PPT) criterion. In the present paper we study important analytical properties of the CCN criterion. We show that in contrast to the PPT criterion it is not sufficient in dimension 2x2. In higher dimensions, theorems connecting the fidelity of a quantum state with the CCN criterion are proved. We also analyze the behavior of the CCN criterion under local operations and identify the operations that leave it invariant. It turns out that the CCN criterion is in general not invariant under local operations

  11. Students Engaged in Learning

    Science.gov (United States)

    Ismail, Emad A.; Groccia, James E.

    2018-01-01

    Engaging students in learning is a basic principle of effective undergraduate education. Outcomes of engaging students include meaningful learning experiences and enhanced skills in all learning domains. This chapter reviews the influence of engaging students in different forms of active learning on cognitive, psychomotor, and affective skill…

  12. Predicting the onset of cracks in bulk metal forming by ductile damage criteria

    DEFF Research Database (Denmark)

    Christiansen, Peter; Nielsen, Chris Valentin; Martins, Paulo A.F.

    2017-01-01

    Three different ductile damage criteria, Ayada, normalized Cockcroft and Latham and a new shear stress based criterion taking into account hydrostatic tension, are utilized for predicting the onset of cracks in various deformation processes. It is found that the Ayada criterion predicts well...... the onset of cracks when they originate from hydrostatic tension. The shear based criterion predicts cracks triggered by shear and the normalized Cockcroft and Latham criterion indicates the overall area of onset of cracks caused by either hydrostatic or shear stresses. However the prediction...... is not as accurate as the Ayada criterion for cracks caused by hydrostatic tension....

  13. Designing for user engagement

    CERN Document Server

    Geisler, Cheryl

    2013-01-01

    Designing for User Engagement on the Web: 10 Basic Principles is concerned with making user experience engaging. The cascade of social web applications we are now familiar with - blogs, consumer reviews, wikis, and social networking - are all engaging experiences. But engagement is an increasingly common goal in business and productivity environments as well. This book provides a foundation for all those seeking to design engaging user experiences rich in communication and interaction. Combining a handbook on basic principles with case studies, it provides readers with a ric

  14. Joined application of a multiaxial critical plane criterion and a strain energy density criterion in low-cycle fatigue

    Directory of Open Access Journals (Sweden)

    Andrea Carpinteri

    2017-07-01

    Full Text Available In the present paper, the multiaxial fatigue life assessment of notched structural components is performed by employing a strain-based multiaxial fatigue criterion. Such a criterion, depending on the critical plane concept, is extended by implementing the control volume concept reated to the Strain Energy Density (SED approach: a material point located at a certain distance from the notch tip is assumed to be the verification point where to perform the above assessment. Such a distance, measured along the notch bisector, is a function of both the biaxiality ratio (defined as the ratio between the applied shear stress amplitude and the normal stress amplitude and the control volume radii under Mode I and Mode III. Once the position of the verification point is determined, the fatigue lifetime is assessed through an equivalent strain amplitude, acting on the critical plane, together with a unique material reference curve (i.e. the Manson-Coffin curve. Some uniaxial and multiaxial fatigue data related to V-notched round bars made of titanium grade 5 alloy (Ti-6Al-4V are examined to validate the present criterion.

  15. Geoscience Education and Public Outreach AND CRITERION 2: MAKING A BROADER IMPACT

    Science.gov (United States)

    Marlino, M.; Scotchmoor, J. G.

    2005-12-01

    The geosciences influence our daily lives and yet often go unnoticed by the general public. From the moment we listen to the weather report and fill-up our cars for the daily commute, until we return to our homes constructed from natural resources, we rely on years of scientific research. The challenge facing the geosciences is to make explicit to the public not only the criticality of the research whose benefits they enjoy, but also to actively engage them as partners in the research effort, by providing them with sufficient understanding of the scientific enterprise so that they become thoughtful and proactive when making decisions in the polling booth. Today, there is broad recognition within the science and policy community that communication needs to be more effective, more visible, and that the public communication of the scientific enterprise is critical not only to its taxpayer support, but also to maintenance of a skilled workforce and the standard of living expected by many Americans. In 1997, the National Science Board took the first critical step in creating a cultural change in the scientific community by requiring explicit consideration of the broader impacts of research in every research proposal. The so-called Criterion 2 has catalyzed a dramatic shift in expectations within the geoscience community and an incentive for finding ways to encourage the science research community to select education and public outreach as a venue for responding to Criterion 2. In response, a workshop organized by the University of California Museum of Paleontology and the Digital Library for Earth System Education (DLESE) was held on the Berkeley campus May 11-13, 2005. The Geoscience EPO Workshop purposefully narrowed its focus to that of education and public outreach. This workshop was based on the premise that there are proven models and best practices for effective outreach strategies that need to be identified and shared with research scientists. Workshop

  16. Carbon emissions and an equitable emission reduction criterion

    International Nuclear Information System (INIS)

    Golomb, Dan

    1999-01-01

    In 1995 the world-wide carbon emissions reached 5.8 billion metric tonnes per year (GTC/y). The Kyoto protocol calls for a reduction of carbon emissions from the developed countries (Annex I countries) of 6-8% below 1990 levels on the average, and unspecified commitments for the less developed (non-Annex I) countries. It is doubtful that the Kyoto agreement will be ratified by some parliaments, especially the USA Congress. Furthermore, it is shown that if the non-Annex I countries will not curtail their carbon emissions drastically, the global emissions will soar to huge levels by the middle of the next century. An equitable emission criterion is proposed which may lead to a sustainable rate of growth of carbon emissions, and be acceptable to all countries of the world. The criterion links the rate of growth of carbon emissions to the rate of growth of the Gross Domestic Product (GDP). A target criterion is proposed R = 0.15 KgC/SGDP, which is the current average for western European countries and Japan. This allows for both the growth of the GDP and carbon emissions. However, to reach the target in a reasonable time, the countries for which R≤ 0.3 would be allowed a carbon emission growth rate of 1%./y, and countries for which R≥ 0.3, 0.75%/y. It is shown that by 2050 the world-wide carbon emissions would reach about 10 GTC/y, which is about 3 times less than the Kyoto agreement would allow. (Author)

  17. Development of Predictor and Criterion Measures for the NCO21 Research Program

    National Research Council Canada - National Science Library

    Knapp, Deidre

    2002-01-01

    ... incorporated into an NCO performance management system geared to 21st century job demands. This report documents the design and development of predictor and criterion measures that will be used in a criterion-related validation data collection...

  18. Sensor Calibration Design Based on D-Optimality Criterion

    Directory of Open Access Journals (Sweden)

    Hajiyev Chingiz

    2016-09-01

    Full Text Available In this study, a procedure for optimal selection of measurement points using the D-optimality criterion to find the best calibration curves of measurement sensors is proposed. The coefficients of calibration curve are evaluated by applying the classical Least Squares Method (LSM. As an example, the problem of optimal selection for standard pressure setters when calibrating a differential pressure sensor is solved. The values obtained from the D-optimum measurement points for calibration of the differential pressure sensor are compared with those from actual experiments. Comparison of the calibration errors corresponding to the D-optimal, A-optimal and Equidistant calibration curves is done.

  19. Adjustment Criterion and Algorithm in Adjustment Model with Uncertain

    Directory of Open Access Journals (Sweden)

    SONG Yingchun

    2015-02-01

    Full Text Available Uncertainty often exists in the process of obtaining measurement data, which affects the reliability of parameter estimation. This paper establishes a new adjustment model in which uncertainty is incorporated into the function model as a parameter. A new adjustment criterion and its iterative algorithm are given based on uncertainty propagation law in the residual error, in which the maximum possible uncertainty is minimized. This paper also analyzes, with examples, the different adjustment criteria and features of optimal solutions about the least-squares adjustment, the uncertainty adjustment and total least-squares adjustment. Existing error theory is extended with new observational data processing method about uncertainty.

  20. Geometric steering criterion for two-qubit states

    Science.gov (United States)

    Yu, Bai-Chu; Jia, Zhih-Ahn; Wu, Yu-Chun; Guo, Guang-Can

    2018-01-01

    According to the geometric characterization of measurement assemblages and local hidden state (LHS) models, we propose a steering criterion which is both necessary and sufficient for two-qubit states under arbitrary measurement sets. A quantity is introduced to describe the required local resources to reconstruct a measurement assemblage for two-qubit states. We show that the quantity can be regarded as a quantification of steerability and be used to find out optimal LHS models. Finally we propose a method to generate unsteerable states, and construct some two-qubit states which are entangled but unsteerable under all projective measurements.

  1. Corner-point criterion for assessing nonlinear image processing imagers

    Science.gov (United States)

    Landeau, Stéphane; Pigois, Laurent; Foing, Jean-Paul; Deshors, Gilles; Swiathy, Greggory

    2017-10-01

    Range performance modeling of optronics imagers attempts to characterize the ability to resolve details in the image. Today, digital image processing is systematically used in conjunction with the optoelectronic system to correct its defects or to exploit tiny detection signals to increase performance. In order to characterize these processing having adaptive and non-linear properties, it becomes necessary to stimulate the imagers with test patterns whose properties are similar to the actual scene image ones, in terms of dynamic range, contours, texture and singular points. This paper presents an approach based on a Corner-Point (CP) resolution criterion, derived from the Probability of Correct Resolution (PCR) of binary fractal patterns. The fundamental principle lies in the respectful perception of the CP direction of one pixel minority value among the majority value of a 2×2 pixels block. The evaluation procedure considers the actual image as its multi-resolution CP transformation, taking the role of Ground Truth (GT). After a spatial registration between the degraded image and the original one, the degradation is statistically measured by comparing the GT with the degraded image CP transformation, in terms of localized PCR at the region of interest. The paper defines this CP criterion and presents the developed evaluation techniques, such as the measurement of the number of CP resolved on the target, the transformation CP and its inverse transform that make it possible to reconstruct an image of the perceived CPs. Then, this criterion is compared with the standard Johnson criterion, in the case of a linear blur and noise degradation. The evaluation of an imaging system integrating an image display and a visual perception is considered, by proposing an analysis scheme combining two methods: a CP measurement for the highly non-linear part (imaging) with real signature test target and conventional methods for the more linear part (displaying). The application to

  2. The alternative DSM-5 personality disorder traits criterion

    DEFF Research Database (Denmark)

    Bach, Bo; Maples-Keller, Jessica L; Bo, Sune

    2016-01-01

    The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; American Psychiatric Association, 2013a) offers an alternative model for Personality Disorders (PDs) in Section III, which consists in part of a pathological personality traits criterion measured...... with the Personality Inventory for DSM-5 (PID-5). The PID-5 selfreport instrument currently exists in the original 220-item form, a short 100-item form, and a brief 25-item form. For clinicians and researchers, the choice of a particular PID- 5 form depends on feasibility, but also reliability and validity. The goal...

  3. An opening criterion for dust gaps in protoplanetary discs

    OpenAIRE

    Dipierro, Giovanni; Laibe, Guillaume

    2017-01-01

    We aim to understand under which conditions a low mass planet can open a gap in viscous dusty protoplanetary discs. For this purpose, we extend the theory of dust radial drift to include the contribution from the tides of an embedded planet and from the gas viscous forces. From this formalism, we derive i) a grain size-dependent criterion for dust gap opening in discs, ii) an estimate of the location of the outer edge of the dust gap and iii) an estimate of the minimum Stokes number above whi...

  4. Forecastability as a Design Criterion in Wind Resource Assessment: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.; Hodge, B. M.

    2014-04-01

    This paper proposes a methodology to include the wind power forecasting ability, or 'forecastability,' of a site as a design criterion in wind resource assessment and wind power plant design stages. The Unrestricted Wind Farm Layout Optimization (UWFLO) methodology is adopted to maximize the capacity factor of a wind power plant. The 1-hour-ahead persistence wind power forecasting method is used to characterize the forecastability of a potential wind power plant, thereby partially quantifying the integration cost. A trade-off between the maximum capacity factor and the forecastability is investigated.

  5. Critical machine cluster identification using the equal area criterion

    DEFF Research Database (Denmark)

    Weckesser, Johannes Tilman Gabriel; Jóhannsson, Hjörtur; Østergaard, Jacob

    2015-01-01

    The paper introduces a new method to early identify the critical machine cluster (CMC) after a transient disturbance. For transient stability assessment with methods based on the equal area criterion it is necessary to split the generators into a group of critical and non-critical machines....... The generators in the CMC are those likely to lose synchronism. The early and reliable identification of the CMC is crucial and one of the major challenges. The proposed new approach is based on the assessment of the rotor dynamics between two machines and the evaluation of their coupling strength. A novel...

  6. No rationale for 1 variable per 10 events criterion for binary logistic regression analysis

    Directory of Open Access Journals (Sweden)

    Maarten van Smeden

    2016-11-01

    Full Text Available Abstract Background Ten events per variable (EPV is a widely advocated minimal criterion for sample size considerations in logistic regression analysis. Of three previous simulation studies that examined this minimal EPV criterion only one supports the use of a minimum of 10 EPV. In this paper, we examine the reasons for substantial differences between these extensive simulation studies. Methods The current study uses Monte Carlo simulations to evaluate small sample bias, coverage of confidence intervals and mean square error of logit coefficients. Logistic regression models fitted by maximum likelihood and a modified estimation procedure, known as Firth’s correction, are compared. Results The results show that besides EPV, the problems associated with low EPV depend on other factors such as the total sample size. It is also demonstrated that simulation results can be dominated by even a few simulated data sets for which the prediction of the outcome by the covariates is perfect (‘separation’. We reveal that different approaches for identifying and handling separation leads to substantially different simulation results. We further show that Firth’s correction can be used to improve the accuracy of regression coefficients and alleviate the problems associated with separation. Conclusions The current evidence supporting EPV rules for binary logistic regression is weak. Given our findings, there is an urgent need for new research to provide guidance for supporting sample size considerations for binary logistic regression analysis.

  7. No rationale for 1 variable per 10 events criterion for binary logistic regression analysis.

    Science.gov (United States)

    van Smeden, Maarten; de Groot, Joris A H; Moons, Karel G M; Collins, Gary S; Altman, Douglas G; Eijkemans, Marinus J C; Reitsma, Johannes B

    2016-11-24

    Ten events per variable (EPV) is a widely advocated minimal criterion for sample size considerations in logistic regression analysis. Of three previous simulation studies that examined this minimal EPV criterion only one supports the use of a minimum of 10 EPV. In this paper, we examine the reasons for substantial differences between these extensive simulation studies. The current study uses Monte Carlo simulations to evaluate small sample bias, coverage of confidence intervals and mean square error of logit coefficients. Logistic regression models fitted by maximum likelihood and a modified estimation procedure, known as Firth's correction, are compared. The results show that besides EPV, the problems associated with low EPV depend on other factors such as the total sample size. It is also demonstrated that simulation results can be dominated by even a few simulated data sets for which the prediction of the outcome by the covariates is perfect ('separation'). We reveal that different approaches for identifying and handling separation leads to substantially different simulation results. We further show that Firth's correction can be used to improve the accuracy of regression coefficients and alleviate the problems associated with separation. The current evidence supporting EPV rules for binary logistic regression is weak. Given our findings, there is an urgent need for new research to provide guidance for supporting sample size considerations for binary logistic regression analysis.

  8. [On the problems of the evolutionary optimization of life history. II. To justification of optimization criterion for nonlinear Leslie model].

    Science.gov (United States)

    Pasekov, V P

    2013-03-01

    The paper considers the problems in the adaptive evolution of life-history traits for individuals in the nonlinear Leslie model of age-structured population. The possibility to predict adaptation results as the values of organism's traits (properties) that provide for the maximum of a certain function of traits (optimization criterion) is studied. An ideal criterion of this type is Darwinian fitness as a characteristic of success of an individual's life history. Criticism of the optimization approach is associated with the fact that it does not take into account the changes in the environmental conditions (in a broad sense) caused by evolution, thereby leading to losses in the adequacy of the criterion. In addition, the justification for this criterion under stationary conditions is not usually rigorous. It has been suggested to overcome these objections in terms of the adaptive dynamics theory using the concept of invasive fitness. The reasons are given that favor the application of the average number of offspring for an individual, R(L), as an optimization criterion in the nonlinear Leslie model. According to the theory of quantitative genetics, the selection for fertility (that is, for a set of correlated quantitative traits determined by both multiple loci and the environment) leads to an increase in R(L). In terms of adaptive dynamics, the maximum R(L) corresponds to the evolutionary stability and, in certain cases, convergent stability of the values for traits. The search for evolutionarily stable values on the background of limited resources for reproduction is a problem of linear programming.

  9. Stress, alcohol use and work engagement among university workers ...

    African Journals Online (AJOL)

    ... workplace alcohol use and work engagement among 228 University of Nigeria, Nsukka, workers. The results of the regression analyses showed that job stress significantly predicted workplace alcohol use (â = .17, p < .01). Workplace alcohol use also significantly predicted employee work engagement (â = -.35, p < .001).

  10. Burnout and engagement of reformed church ministers

    Directory of Open Access Journals (Sweden)

    Chenelle Buys

    2010-06-01

    Research purpose: The objective of this study was to investigate the effects of job-demands and job-resources on ministers’ burnout and engagement. Congregational commitment and health were included as possible consequences of burnout and engagement. Motivation for the study: Ministers’ well-being has become an important topic for both researchers and practitioners. Research design, approach and method: A survey design with a non-probability, purposive voluntary sample of 115 ministers was used. The Job-Demands–Resources Questionnaire, Maslach Burnout Inventory, Work Engagement Scale, General Health Questionnaire, and Congregational Commitment Scale were administered. Main findings: Regression analysis indicated that the pace, amount of work and emotional demands were indicators of burnout while growth opportunities, social support and job significance were indicators of engagement. Furthermore, it was found that exhaustion predicted somatic symptoms and depression, while mental distance predicted depression. Engagement predicted social functioning and affective commitment. Practical implications: Interventions should be implemented to help ministers deal more effectively with any burnout symptoms experienced in order to prevent ministers who are already showing signs of burnout from getting sick to increase their engagement and to rehabilitate individuals who are ill as a result of the work place. Contribution: The study contributes to knowledge regarding the effects of job-demands and resources on the well-being of ministers.

  11. Novel criterion for formation of metastable phase from undercooled melt

    International Nuclear Information System (INIS)

    Kuribayashi, Kazuhiko; Nagashio, Kosuke; Niwata, Kenji; Kumar, M.S. Vijaya; Hibiya, Taketoshi

    2007-01-01

    Undercooling a melt facilitates the preferential nucleation of a metastable phase. In the present study, the formation of metastable phases from undercooled melts was considered from the viewpoint of the competitive nucleation criterion. The classical nucleation theory shows us that the most critical factor for forming a critical nucleus is the interface free energy σ. Furthermore, Spaepen's negentropic model on σ generated the role of the scaling factor α that depends on the polyhedral order in the liquid and solid phases prominent in simple liquids such as the melt of monoatomic metals. In ionic materials such as oxides, however, in which oxygen polyhedrons including a cation at their center are the structural units both in the solid and liquid phases, the entropy of fusion, rather than α, can be expected to become dominant in the determination of σ. In accordance with this idea, using REFeO 3 as the model material (where RE denotes rare-earth elements) the entropy-undercooling regime criterion was proposed and verified

  12. Physical and Constructive (Limiting) Criterions of Gear Wheels Wear

    Science.gov (United States)

    Fedorov, S. V.

    2018-01-01

    We suggest using a generalized model of friction - the model of elastic-plastic deformation of the body element, which is located on the surface of the friction pairs. This model is based on our new engineering approach to the problem of friction-triboergodynamics. Friction is examined as transformative and dissipative process. Structural-energetic interpretation of friction as a process of elasto-plastic deformation and fracture contact volumes is proposed. The model of Hertzian (heavy-loaded) friction contact evolution is considered. The least wear particle principle is formulated. It is mechanical (nano) quantum. Mechanical quantum represents the least structural form of solid material body in conditions of friction. It is dynamic oscillator of dissipative friction structure and it can be examined as the elementary nanostructure of metal’s solid body. At friction in state of most complete evolution of elementary tribosystem (tribocontact) all mechanical quanta (subtribosystems) with the exception of one, elasticity and reversibly transform energy of outer impact (mechanic movement). In these terms only one mechanical quantum is the lost - standard of wear. From this position we can consider the physical criterion of wear and the constructive (limiting) criterion of gear teeth and other practical examples of tribosystems efficiency with new tribology notion - mechanical (nano) quantum.

  13. Some comments about the use of J1 integral criterion

    International Nuclear Information System (INIS)

    Roche, Roland.

    1977-01-01

    Use of J 1 integral criterion in Post Yield Fracture Mechanics is considered. If J 1 is path independent, it can be considered as a crack tip singularity characterization and then, as a good criterion for crack initiation. But it is not proved that J 1 is path independent in general case. The current practice is to consider a material with a mechanical potential energy, it is to say to suppose that strain energy W is only function of the state of strain, but not of the loading history. It is possible to introduce the defect vector concept (or driving force). The resultants of defect vectors included inside a volume are the surface integrals J vector and L vector. So the general condition for J 1 path indepedence can be written. It seems that J 1 is path independent for radial loading but the question is still open for more complex ways of loading. What is the effect of material memory on the J 1 path dependence [fr

  14. A dimensionless criterion for characterising internal transport barriers in tokamaks

    International Nuclear Information System (INIS)

    Tresset, G.; Litaudon, X.; Moreau, D.

    2000-07-01

    A simple criterion, based on a dimensionless parameter (ρ T * =ρ s /L T ) related to drift wave turbulence stabilisation and anomalous transport theory, is proposed in order to characterise the emergence and the space-time evolution of internal transport barriers (ITB's) during a tokamak discharge. The underlying physics which led us to consider the possible relevance of this parameter as a local indicator of a bifurcated plasma state is the breaking of the gyro-Bohm turbulence scaling by the diamagnetic velocity shear, which has been observed in various numerical simulations [e.g. X. Garbet and R.E. Waltz, Phys. Plasmas 3(1996) 1898]. The presence of an ITB is inferred when ρ T * exceeds a threshold value. The main features like the emergence time, location and even dynamics of ITB's can then be summarized on a single graphical representation consistent with measurement uncertainties. The validity of such a criterion is demonstrated on the Optimized Shear (OS) database of JET in several experimental configurations. Large database analysis and realtime control of OS discharges are envisaged as the most attractive applications. (author)

  15. The limits of the Bohm criterion in collisional plasmas

    International Nuclear Information System (INIS)

    Valentini, H.-B.; Kaiser, D.

    2015-01-01

    The sheath formation within a low-pressure collisional plasma is analysed by means of a two-fluid model. The Bohm criterion takes into account the effects of the electric field and the inertia of the ions. Numerical results yield that these effects contribute to the space charge formation, only, if the collisionality is lower than a relatively small threshold. It follows that a lower and an upper limit of the drift speed of the ions exist where the effects treated by Bohm can form a sheath. This interval becomes narrower as the collisionality increases and vanishes at the mentioned threshold. Above the threshold, the sheath is mainly created by collisions and the ionisation. Under these conditions, the sheath formation cannot be described by means of Bohm like criteria. In a few references, a so-called upper limit of the Bohm criterion is stated for collisional plasmas where the momentum equation of the ions is taken into account, only. However, the present paper shows that this limit results in an unrealistically steep increase of the space charge density towards the wall, and, therefore, it yields no useful limit of the Bohm velocity

  16. A proposed risk acceptance criterion for nuclear fuel waste disposal

    International Nuclear Information System (INIS)

    Mehta, K.

    1985-06-01

    The need to establish a radiological protection criterion that applies specifically to disposal of high level nuclear fuel wastes arises from the difficulty of applying the present ICRP recommendations. These recommendations apply to situations in which radiological detriment can be actively controlled, while a permanent waste disposal facility is meant to operate without the need for corrective actions. Also, the risks associated with waste disposal depend on events and processes that have various probabilities of occurrence. In these circumstances, it is not suitable to apply standards that are based on a single dose limit as in the present ICRP recommendations, because it will generally be possible to envisage events, perhaps rare, that would lead to doses above any selected limit. To overcome these difficulties, it is proposed to base a criterion for acceptability on a set of dose values and corresponding limiting values of probabilities; this set of values constitutes a risk-limit line. A risk-limit line suitable for waste disposal is proposed that has characteristics consistent with the basic philosophy of the ICRP and UNSCEAR recommendations, and is based on levels on natural background radiation

  17. Cue quality and criterion setting in recognition memory.

    Science.gov (United States)

    Kent, Christopher; Lamberts, Koen; Patton, Richard

    2018-02-02

    Previous studies on how people set and modify decision criteria in old-new recognition tasks (in which they have to decide whether or not a stimulus was seen in a study phase) have almost exclusively focused on properties of the study items, such as presentation frequency or study list length. In contrast, in the three studies reported here, we manipulated the quality of the test cues in a scene-recognition task, either by degrading through Gaussian blurring (Experiment 1) or by limiting presentation duration (Experiment 2 and 3). In Experiments 1 and 2, degradation of the test cue led to worse old-new discrimination. Most importantly, however, participants were more liberal in their responses to degraded cues (i.e., more likely to call the cue "old"), demonstrating strong within-list, item-by-item, criterion shifts. This liberal response bias toward degraded stimuli came at the cost of increasing the false alarm rate while maintaining a constant hit rate. Experiment 3 replicated Experiment 2 with additional stimulus types (words and faces) but did not provide accuracy feedback to participants. The criterion shifts in Experiment 3 were smaller in magnitude than Experiments 1 and 2 and varied in consistency across stimulus type, suggesting, in line with previous studies, that feedback is important for participants to shift their criteria.

  18. Job shop scheduling problem with late work criterion

    Science.gov (United States)

    Piroozfard, Hamed; Wong, Kuan Yew

    2015-05-01

    Scheduling is considered as a key task in many industries, such as project based scheduling, crew scheduling, flight scheduling, machine scheduling, etc. In the machine scheduling area, the job shop scheduling problems are considered to be important and highly complex, in which they are characterized as NP-hard. The job shop scheduling problems with late work criterion and non-preemptive jobs are addressed in this paper. Late work criterion is a fairly new objective function. It is a qualitative measure and concerns with late parts of the jobs, unlike classical objective functions that are quantitative measures. In this work, simulated annealing was presented to solve the scheduling problem. In addition, operation based representation was used to encode the solution, and a neighbourhood search structure was employed to search for the new solutions. The case studies are Lawrence instances that were taken from the Operations Research Library. Computational results of this probabilistic meta-heuristic algorithm were compared with a conventional genetic algorithm, and a conclusion was made based on the algorithm and problem.

  19. Comparing hierarchical models via the marginalized deviance information criterion.

    Science.gov (United States)

    Quintero, Adrian; Lesaffre, Emmanuel

    2018-07-20

    Hierarchical models are extensively used in pharmacokinetics and longitudinal studies. When the estimation is performed from a Bayesian approach, model comparison is often based on the deviance information criterion (DIC). In hierarchical models with latent variables, there are several versions of this statistic: the conditional DIC (cDIC) that incorporates the latent variables in the focus of the analysis and the marginalized DIC (mDIC) that integrates them out. Regardless of the asymptotic and coherency difficulties of cDIC, this alternative is usually used in Markov chain Monte Carlo (MCMC) methods for hierarchical models because of practical convenience. The mDIC criterion is more appropriate in most cases but requires integration of the likelihood, which is computationally demanding and not implemented in Bayesian software. Therefore, we consider a method to compute mDIC by generating replicate samples of the latent variables that need to be integrated out. This alternative can be easily conducted from the MCMC output of Bayesian packages and is widely applicable to hierarchical models in general. Additionally, we propose some approximations in order to reduce the computational complexity for large-sample situations. The method is illustrated with simulated data sets and 2 medical studies, evidencing that cDIC may be misleading whilst mDIC appears pertinent. Copyright © 2018 John Wiley & Sons, Ltd.

  20. ACTION AS A CRITERION OF THE CAR OPERATING EFFECTIVENES

    Directory of Open Access Journals (Sweden)

    Stefan POSTRZEDNIK

    2016-06-01

    Full Text Available Currently used criteria for determining car operating efficiency in road traffic are, among others, emission of harmful substances, consumption of engine driving fuels, technical service and reliability of operation, safety of use. The operational characteristics of the car in terms of engine driving fuel consumption data is usually recognised as so-called road specific fuel consumption. An important deficiency of this approach is the failure to take into account the influence of the time on the journey’s effectiveness and the final result of the entire project. To obtain a new solution in this range in the analysis, a quantity called "action", which at last will be treated as the criterion of the car operating effectiveness, was used. The quantity of action is the product of the performed work and its realisation time. Many phenomena and processes in nature take place according to the principle of "minimum of action"  this criterion can be applied in the analysis of the car’s operating efficiency taking place in road traffic. An approach of this issue is presented in this article, wherein the basic data for analysis were obtained in the framework of the car tests performed at the real traffic conditions.

  1. PET image reconstruction: mean, variance, and optimal minimax criterion

    International Nuclear Information System (INIS)

    Liu, Huafeng; Guo, Min; Gao, Fei; Shi, Pengcheng; Xue, Liying; Nie, Jing

    2015-01-01

    Given the noise nature of positron emission tomography (PET) measurements, it is critical to know the image quality and reliability as well as expected radioactivity map (mean image) for both qualitative interpretation and quantitative analysis. While existing efforts have often been devoted to providing only the reconstructed mean image, we present a unified framework for joint estimation of the mean and corresponding variance of the radioactivity map based on an efficient optimal min–max criterion. The proposed framework formulates the PET image reconstruction problem to be a transformation from system uncertainties to estimation errors, where the minimax criterion is adopted to minimize the estimation errors with possibly maximized system uncertainties. The estimation errors, in the form of a covariance matrix, express the measurement uncertainties in a complete way. The framework is then optimized by ∞-norm optimization and solved with the corresponding H ∞ filter. Unlike conventional statistical reconstruction algorithms, that rely on the statistical modeling methods of the measurement data or noise, the proposed joint estimation stands from the point of view of signal energies and can handle from imperfect statistical assumptions to even no a priori statistical assumptions. The performance and accuracy of reconstructed mean and variance images are validated using Monte Carlo simulations. Experiments on phantom scans with a small animal PET scanner and real patient scans are also conducted for assessment of clinical potential. (paper)

  2. Refocusing criterion via sparsity measurements in digital holography.

    Science.gov (United States)

    Memmolo, Pasquale; Paturzo, Melania; Javidi, Bahram; Netti, Paolo A; Ferraro, Pietro

    2014-08-15

    Several automatic approaches have been proposed in the past to compute the refocus distance in digital holography (DH). However most of them are based on a maximization or minimization of a suitable amplitude image contrast measure, regarded as a function of the reconstruction distance parameter. Here we show that, by using the sparsity measure coefficient regarded as a refocusing criterion in the holographic reconstruction, it is possible to recover the focus plane and, at the same time, establish the degree of sparsity of digital holograms, when samples of the diffraction Fresnel propagation integral are used as a sparse signal representation. We employ a sparsity measurement coefficient known as Gini's index thus showing for the first time, to the best of our knowledge, its application in DH, as an effective refocusing criterion. Demonstration is provided for different holographic configurations (i.e., lens and lensless apparatus) and for completely different objects (i.e., a thin pure phase microscopic object as an in vitro cell, and macroscopic puppets) preparation.

  3. An extension of theoretical analysis for the onset of slugging criterion in horizontal stratified air-water countercurrent flow

    International Nuclear Information System (INIS)

    Lee, Byung Ryung

    1997-02-01

    This paper presents an experimental and theoretical investigation of interfacial friction factor, wave height and transition criterion from wavy to slug flow in a long horizontal air-water countercurrent stratified flow condition. A series of experiments have been conducted in adiabatic countercurrent stratified flow with the round pipe and rectangular duct test section to develop the interfacial friction factor and the criterion of onset of slugging in horizontal air-water countercurrent stratified flow. An adiabatic semi-empirical correlation for interfacial friction factor has been developed based on the surface roughness concept. A comparison of the measured data in this study and of other investigators with the predictions of the present correlation shows that the agreement is within ±30% error, and that the present correlation is applicable to a broader range of water flow rate than the correlations of previous investigators. The theories which can calculate the wave height and criteria of onset of slug flow in a stratified wavy flow regime have been developed based on the concept of total energy conservation and also wave theory. This theoretical criteria agree better with the measured data than the other criteria available in the literature, but the criteria range about 92∼107% of the measured data. An empirical formula for the criterion has been also developed and compared with the formula in the literatures. Comparison between the measured data and the predictions of the present theory shows that the agreement is within ±8%

  4. Surrogate screening models for the low physical activity criterion of frailty.

    Science.gov (United States)

    Eckel, Sandrah P; Bandeen-Roche, Karen; Chaves, Paulo H M; Fried, Linda P; Louis, Thomas A

    2011-06-01

    Low physical activity, one of five criteria in a validated clinical phenotype of frailty, is assessed by a standardized, semiquantitative questionnaire on up to 20 leisure time activities. Because of the time demanded to collect the interview data, it has been challenging to translate to studies other than the Cardiovascular Health Study (CHS), for which it was developed. Considering subsets of activities, we identified and evaluated streamlined surrogate assessment methods and compared them to one implemented in the Women's Health and Aging Study (WHAS). Using data on men and women ages 65 and older from the CHS, we applied logistic regression models to rank activities by "relative influence" in predicting low physical activity.We considered subsets of the most influential activities as inputs to potential surrogate models (logistic regressions). We evaluated predictive accuracy and predictive validity using the area under receiver operating characteristic curves and assessed criterion validity using proportional hazards models relating frailty status (defined using the surrogate) to mortality. Walking for exercise and moderately strenuous household chores were highly influential for both genders. Women required fewer activities than men for accurate classification. The WHAS model (8 CHS activities) was an effective surrogate, but a surrogate using 6 activities (walking, chores, gardening, general exercise, mowing and golfing) was also highly predictive. We recommend a 6 activity questionnaire to assess physical activity for men and women. If efficiency is essential and the study involves only women, fewer activities can be included.

  5. Study of criterion for assuring the effectiveness of cathodic protection of buried steel pipelines being interfered with alternative current

    Energy Technology Data Exchange (ETDEWEB)

    He, X.; Jiang, G.; Qiu, Y.; Tang, H. [College of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan (China); Zhang, G.; Jin, X.; Xiang, Z. [Huazhong Natural Gas Subsidiary of PetroChina Pipeline Company, Wuhan (China); Zhang, Z. [Dwell Company Limited, PetroChina Engineering Company, Ltd, Beijing (China)

    2012-06-15

    Interference of alternative current (AC) on corrosion of X65 steel was investigated in soil. It was observed that the unfavorable effect of interfering AC was able to be effectively inhibited by increasing the direct current density of the cathodic protection (CP) system. A clear correlation was established between the CP current density and the tolerable AC current density. This led to a new criterion for assuring the effectiveness of CP of buried pipelines being interfered with AC. Field experimental results on a buried pipeline running below a 500 kV transmission line showed that the criterion could satisfactorily predict the risk of AC interfering on the CP system. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. ON THE VALIDITY OF THE 'HILL RADIUS CRITERION' FOR THE EJECTION OF PLANETS FROM STELLAR HABITABLE ZONES

    International Nuclear Information System (INIS)

    Cuntz, M.; Yeager, K. E.

    2009-01-01

    We challenge the customary assumption that the entering of an Earth-mass planet into the Hill radius (or multiples of the Hill radius) of a giant planet is a valid criterion for its ejection from the star-planet system. This assumption has widely been used in previous studies, especially those with an astrobiological focus. As intriguing examples, we explore the dynamics of the systems HD 20782 and HD 188015. Each system possesses a giant planet that remains in or crosses into the stellar habitable zone, thus effectively thwarting the possibility of habitable terrestrial planets. In the case of HD 188015, the orbit of the giant planet is almost circular, whereas in the case of HD 20782, it is extremely elliptical. Although it is found that Earth-mass planets are eventually ejected from the habitable zones of these systems, the 'Hill Radius Criterion' is identified as invalid for the prediction of when the ejection is actually occurring.

  7. Approaching Engagement towards Human-Engaged Computing

    DEFF Research Database (Denmark)

    Niksirat, Kavous Salehzadeh; Sarcar, Sayan; Sun, Huatong

    2018-01-01

    Debates regarding the nature and role of HCI research and practice have intensified in recent years, given the ever increasingly intertwined relations between humans and technologies. The framework of Human-Engaged Computing (HEC) was proposed and developed over a series of scholarly workshops to...

  8. Proposal of failure criterion applicable to finite element analysis results for wall-thinned pipes under bending load

    Energy Technology Data Exchange (ETDEWEB)

    Meshii, Toshiyuki, E-mail: meshii@u-fukui.ac.jp [Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui (Japan); Ito, Yoshiaki [Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui (Japan)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer Limit bending load (LBL) of wall-thinned pipe by large strain FEA was considered. Black-Right-Pointing-Pointer Net section yield load had sufficient margin to LBL. Black-Right-Pointing-Pointer LBL for collapse was the load when volume with nominal thickness yielded. Black-Right-Pointing-Pointer LBL for cracking was the load when flawed section stress exceeded tensile strength. Black-Right-Pointing-Pointer Failure criterion considering above was named Domain Collapse Criterion. - Abstract: In this work, a failure criterion applicable to large strain Finite Element Analysis (FEA) results was proposed in order to predict both the fracture mode (collapse or cracking) and the limit bending load of wall-thinned straight pipes. This work was motivated from the recent experimental results of ; that is, fracture mode is not always collapse, and the fracture mode affects the limit bending load. The key finding in comparing their test results and a detailed large strain FEA results was that the Mises stress distribution at the limit bending load of a flawed cylinder was similar to that of a flawless cylinder; specifically, in case of collapse, the Mises stress exceeded the true yield stress of a material for the whole 'volume' of a cylinder with a nominal wall thickness. Based on this finding, a failure criterion applicable to large strain FEA results of wall-thinned straight pipes under a bending load that can predict both fracture mode and limit bending load was proposed and was named the Domain Collapse Criterion (DCC). DCC predicts the limit bending load as the lower value of either the M{sub c}{sup FEA}, which is the load at which the Mises stress exceeds the true yield strength of a straight pipe for the whole 'volume' with a nominal wall thickness (fracture mode: collapse), or the M{sub c}{sup FEAb}, which is the load at which the Mises stress in a section of the flaw ligament exceeds the true tensile stress

  9. Modeling a failure criterion for U-Mo/Al dispersion fuel

    Science.gov (United States)

    Oh, Jae-Yong; Kim, Yeon Soo; Tahk, Young-Wook; Kim, Hyun-Jung; Kong, Eui-Hyun; Yim, Jeong-Sik

    2016-05-01

    The breakaway swelling in U-Mo/Al dispersion fuel is known to be caused by large pore formation enhanced by interaction layer (IL) growth between fuel particles and Al matrix. In this study, a critical IL thickness was defined as a criterion for the formation of a large pore in U-Mo/Al dispersion fuel. Specifically, the critical IL thickness is given when two neighboring fuel particles come into contact with each other in the developed IL. The model was verified using the irradiation data from the RERTR tests and KOMO-4 test. The model application to full-sized sample irradiations such as IRISs, FUTURE, E-FUTURE, and AFIP-1 tests resulted in conservative predictions. The parametric study revealed that the fuel particle size and the homogeneity of the fuel particle distribution are influential for fuel performance.

  10. Failure criterion for graphene in biaxial loading—a molecular dynamics study

    International Nuclear Information System (INIS)

    Yazdani, Hessam; Hatami, Kianoosh

    2015-01-01

    Molecular dynamics simulations are carried out in order to develop a failure criterion for infinite/bulk graphene in biaxial tension. Stresses along the principal edge configurations of graphene (i.e. armchair and zigzag directions) are normalized to the corresponding uniaxial ultimate strength values. The combinations of normalized stresses resulting in the failure of graphene are used to define failure envelopes (limiting stress ratio surfaces). Results indicate that a bilinear failure envelope can be used to represent the tensile strength of graphene in biaxial loading at different temperatures with reasonable accuracy. A circular failure envelope is also introduced for practical applications. Both failure envelopes define temperature-independent upper limits for the feasible combinations of normalized stresses for a graphene sheet in biaxial loading. Predicted failure modes of graphene under biaxial loading are also shown and discussed. (paper)

  11. Modeling a failure criterion for U–Mo/Al dispersion fuel

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jae-Yong, E-mail: tylor@kaeri.re.kr [Korea Atomic Energy Research Institute, 111, Daedeok-Daero 989 Beon-Gil, Yuseong-Gu, Daejeon 305-353 (Korea, Republic of); Kim, Yeon Soo [Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States); Tahk, Young-Wook; Kim, Hyun-Jung; Kong, Eui-Hyun; Yim, Jeong-Sik [Korea Atomic Energy Research Institute, 111, Daedeok-Daero 989 Beon-Gil, Yuseong-Gu, Daejeon 305-353 (Korea, Republic of)

    2016-05-15

    The breakaway swelling in U–Mo/Al dispersion fuel is known to be caused by large pore formation enhanced by interaction layer (IL) growth between fuel particles and Al matrix. In this study, a critical IL thickness was defined as a criterion for the formation of a large pore in U–Mo/Al dispersion fuel. Specifically, the critical IL thickness is given when two neighboring fuel particles come into contact with each other in the developed IL. The model was verified using the irradiation data from the RERTR tests and KOMO-4 test. The model application to full-sized sample irradiations such as IRISs, FUTURE, E-FUTURE, and AFIP-1 tests resulted in conservative predictions. The parametric study revealed that the fuel particle size and the homogeneity of the fuel particle distribution are influential for fuel performance.

  12. Development of stress-modified fracture strain criterion for ductile fracture of API X65 steel

    International Nuclear Information System (INIS)

    Oh, Chang Kyun; Kim, Yun Jae; Park, Jin Moo; Kim, Woo Sik; Baek, Jong Hyun

    2005-01-01

    This paper presents a stress-modified fracture strain for API X65 steel used for gas pipeline, as a function of stress triaxiality. To determine the stress-modified fracture strain, tension test of bars with four different notch radii, made of API X65 steel, is firstly performed, from which true fracture strains are determined as a function of notch radius. Then detailed elastic-plastic, large strain Finite Element (FE) analyses are performed to estimate variations of stress triaxiality in the notched bars with load. Combining experimental with FE results provides the true fracture strain as a function of stress triaxiality, which is regarded as a criterion of ductile fracture. Application of the developed stress-modified fracture strain to failure prediction of gas pipes made of API X65 steel with various types of defects is discussed

  13. A uniqueness criterion for the Fock quantization of scalar fields with time-dependent mass

    International Nuclear Information System (INIS)

    Cortez, Jeronimo; Mena Marugan, Guillermo A; Olmedo, Javier; Velhinho, Jose M

    2011-01-01

    A major problem in the quantization of fields in curved spacetimes is the ambiguity in the choice of a Fock representation for the canonical commutation relations. There exists infinite number of choices leading to different physical predictions. In stationary scenarios, a common strategy is to select a vacuum (or a family of unitarily equivalent vacua) by requiring invariance under the spacetime symmetries. When stationarity is lost, a natural generalization consists in replacing time invariance by unitarity in the evolution. We prove that when the spatial sections are compact, the criterion of a unitary dynamics, together with the invariance under the spatial isometries, suffices to select a unique family of Fock quantizations for a scalar field with time-dependent mass. (fast track communication)

  14. Early Nonresponse in the Antipsychotic Treatment of Acute Mania : A Criterion for Reconsidering Treatment? Results From an Individual Patient Data Meta-Analysis

    NARCIS (Netherlands)

    Welten, Carlijn C M; Koeter, Maarten W J; Wohlfarth, Tamar D; Storosum, Jitschak G; van den Brink, Wim; Gispen-de Wied, Christine C; Leufkens, Hubert G M; Denys, Damiaan A J P

    OBJECTIVE: To investigate whether early nonresponse to antipsychotic treatment of acute mania predicts treatment failure and, if so, to establish the best definition or criterion of an early nonresponse. DATA SOURCES: Short-term efficacy studies assessing antipsychotics that were submitted to the

  15. Sensitivity analysis of respiratory parameter uncertainties: impact of criterion function form and constraints.

    Science.gov (United States)

    Lutchen, K R

    1990-08-01

    A sensitivity analysis based on weighted least-squares regression is presented to evaluate alternative methods for fitting lumped-parameter models to respiratory impedance data. The goal is to maintain parameter accuracy simultaneously with practical experiment design. The analysis focuses on predicting parameter uncertainties using a linearized approximation for joint confidence regions. Applications are with four-element parallel and viscoelastic models for 0.125- to 4-Hz data and a six-element model with separate tissue and airway properties for input and transfer impedance data from 2-64 Hz. The criterion function form was evaluated by comparing parameter uncertainties when data are fit as magnitude and phase, dynamic resistance and compliance, or real and imaginary parts of input impedance. The proper choice of weighting can make all three criterion variables comparable. For the six-element model, parameter uncertainties were predicted when both input impedance and transfer impedance are acquired and fit simultaneously. A fit to both data sets from 4 to 64 Hz could reduce parameter estimate uncertainties considerably from those achievable by fitting either alone. For the four-element models, use of an independent, but noisy, measure of static compliance was assessed as a constraint on model parameters. This may allow acceptable parameter uncertainties for a minimum frequency of 0.275-0.375 Hz rather than 0.125 Hz. This reduces data acquisition requirements from a 16- to a 5.33- to 8-s breath holding period. These results are approximations, and the impact of using the linearized approximation for the confidence regions is discussed.

  16. Engagement Means Everyone

    Science.gov (United States)

    Patton, Carol

    2012-01-01

    Employee engagement is not just HR's responsibility. While HR is responsible for the process of measuring and driving engagement, improving it is actually everyone's responsibility. And that means reducing the barriers to productivity to drive business performance. Training departments can play a pivotal role. Their job is to enhance curriculum or…

  17. The Engagement Gap

    DEFF Research Database (Denmark)

    Tartari, Valentina; Salter, Ammon

    2013-01-01

    Recently, debate on women in academic science has been extended to academics' engagement with industry. We suggest that women tend to engage less in industry collaboration than their male colleagues of similar status. We argue that differences are mitigated by the presence of other women and by s...

  18. On making engagement tangible

    NARCIS (Netherlands)

    van den Broek, Egon; Spink, A.J.; Grieco, F; Krips, O.E.; Loijens, L.W.S.; Noldus, L.P.J.J.; Zimmerman, P.H.

    2012-01-01

    In this article the complexity of the construct engagement and three theories on this topic are discussed. Csikszentmihalyi's theory of flow is taken as starting point for the measurement of engagement. The measurement of each of its eight aspects is discussed, including its pros and cons.

  19. Rules of (Student) Engagement

    Science.gov (United States)

    Buskist, William; Busler, Jessica N.; Kirby, Lauren A. J.

    2018-01-01

    Teachers often think of student engagement in terms of hands-on activities that get students involved in their courses. They seldom consider the larger aspects of the teaching--learning environment that often influence the extent to which students are willing to become engaged in their coursework. In this chapter, we describe five "rules of…

  20. Students Engaged in Teaching

    Science.gov (United States)

    Ford, Channing R.; Wilkins, Emily B.; Groccia, James E.

    2018-01-01

    The role of peer teaching has long been established in academia as a means to foster student engagement in the classroom, increase student learning, and as a way to reduce faculty workload. This chapter highlights the direct and powerful positive impacts of engaging students as teachers upon the student providing the instruction, those receiving…

  1. A criterion and mechanism for power ramp defects

    International Nuclear Information System (INIS)

    Garlick, A.; Gravenor, J.G.

    1978-02-01

    The problem of power ramp defects in water reactor fuel pins is discussed in relation to results recently obtained from ramp experiments in the Steam Generating Heavy Water Reactor. Cladding cracks in the defected fuel pins were similar, both macro- and micro structurally, to those in unirradiated Zircaloy exposed to iodine stress-corrosion cracking (scc) conditions. Furthermore, when the measured stress levels for scc in short-term tests were taken as a criterion for ramp defects, UK fuel modelling codes were found to give a useful indication of defect probability under reactor service conditions. The likelihood of sticking between fuel and cladding is discussed and evidence presented which suggests that even at power a degree of adhesion may be expected in some fuel pins. The ramp defect mechanism is discussed in terms of fission product scc, initiation being by intergranular penetration and propagation by cleavage when suitably orientated grains are exposed to large dilatational stresses ahead of the main crack. (author)

  2. Error sensitivity to refinement: a criterion for optimal grid adaptation

    Science.gov (United States)

    Luchini, Paolo; Giannetti, Flavio; Citro, Vincenzo

    2017-12-01

    Most indicators used for automatic grid refinement are suboptimal, in the sense that they do not really minimize the global solution error. This paper concerns with a new indicator, related to the sensitivity map of global stability problems, suitable for an optimal grid refinement that minimizes the global solution error. The new criterion is derived from the properties of the adjoint operator and provides a map of the sensitivity of the global error (or its estimate) to a local mesh refinement. Examples are presented for both a scalar partial differential equation and for the system of Navier-Stokes equations. In the last case, we also present a grid-adaptation algorithm based on the new estimator and on the FreeFem++ software that improves the accuracy of the solution of almost two order of magnitude by redistributing the nodes of the initial computational mesh.

  3. QV modal distance displacement - a criterion for contingency ranking

    Energy Technology Data Exchange (ETDEWEB)

    Rios, M.A.; Sanchez, J.L.; Zapata, C.J. [Universidad de Los Andes (Colombia). Dept. of Electrical Engineering], Emails: mrios@uniandes.edu.co, josesan@uniandes.edu.co, cjzapata@utp.edu.co

    2009-07-01

    This paper proposes a new methodology using concepts of fast decoupled load flow, modal analysis and ranking of contingencies, where the impact of each contingency is measured hourly taking into account the influence of each contingency over the mathematical model of the system, i.e. the Jacobian Matrix. This method computes the displacement of the reduced Jacobian Matrix eigenvalues used in voltage stability analysis, as a criterion of contingency ranking, considering the fact that the lowest eigenvalue in the normal operation condition is not the same lowest eigenvalue in N-1 contingency condition. It is made using all branches in the system and specific branches according to the IBPF index. The test system used is the IEEE 118 nodes. (author)

  4. Criterion-based clinical audit in obstetrics: bridging the quality gap?

    Science.gov (United States)

    Graham, W J

    2009-06-01

    The Millennium Development Goal 5 - reducing maternal mortality by 75% - is unlikely to be met globally and for the majority of low-income countries. At this time of heightened concern to scale-up services for mothers and babies, it is crucial that not only shortfalls in the quantity of care - in terms of location and financial access - are addressed, but also the quality. Reductions in maternal and perinatal mortality in the immediate term depend in large part on the timely delivery of effective practices in the management of life-threatening complications. Such practices require a functioning health system - including skilled and motivated providers engaged with the women and communities whom they serve. Assuring the quality of this system, the services and the care that women receive requires many inputs, including effective and efficient monitoring mechanisms. The purpose of this article is to summarise the practical steps involved in applying one such mechanism, criterion-based clinical audit (CBCA), and to highlight recent lessons from its application in developing countries. Like all audit tools, the ultimate worth of CBCA relates to the action it stimulates in the health system and among providers.

  5. ADDED VALUE AS EFFICIENCY CRITERION FOR INDUSTRIAL PRODUCTION PROCESS

    Directory of Open Access Journals (Sweden)

    L. M. Korotkevich

    2016-01-01

    Full Text Available Literary analysis has shown that the majority of researchers are using classical efficiency criteria for construction of an optimization model for production process: profit maximization; cost minimization; maximization of commercial product output; minimization of back-log for product demand; minimization of total time consumption due to production change. The paper proposes to use an index of added value as an efficiency criterion because it combines economic and social interests of all main interested subjects of the business activity: national government, property owners, employees, investors. The following types of added value have been considered in the paper: joint-stock, market, monetary, economic, notional (gross, net, real. The paper makes suggestion to use an index of real value added as an efficiency criterion. Such approach permits to bring notional added value in comparable variant because added value can be increased not only due to efficiency improvement of enterprise activity but also due to environmental factors – excess in rate of export price increases over rate of import growth. An analysis of methods for calculation of real value added has been made on a country-by-country basis (extrapolation, simple and double deflation. A method of double deflation has been selected on the basis of the executed analysis and it is counted according to the Laspeyires, Paasche, Fischer indices. A conclusion has been made that the used expressions do not take into account fully economic peculiarities of the Republic of Belarus: they are considered as inappropriate in the case when product cost is differentiated according to marketing outlets; they do not take account of difference in rate of several currencies and such approach is reflected in export price of a released product and import price for raw material, supplies and component parts. Taking this into consideration expressions for calculation of real value added have been specified

  6. PRINCIPLE OF PROPORTIONALITY, CRITERION OF LEGITIMACY IN THE PUBLIC LAW

    Directory of Open Access Journals (Sweden)

    MARIUS ANDREESCU

    2011-04-01

    Full Text Available A problem of essence of the state is the one to delimit the discretionary power, respectively the power abuse in the activity of the state’s institutions. The legal behavior of the state’s institutions consists in their right to appreciate them and the power excess generates the violation of a subjective right or of the right that is of legitimate interest to the citizen. The application and nonobservance of the principle of lawfulness in the activities of the state is a complex problem because the exercise of the state’s functions assumes the discretionary powers with which the states authorities are invested, or otherwise said the ‘right of appreciation” of the authorities regarding the moment of adopting the contents of the measures proposed. The discretionary power cannot be opposed to the principle of lawfulness, as a dimension of the state de jure. In this study we propose to analyze the concept of discretionary power, respectively the power excess, having as a guidance the legislation, jurisprudence and doctrine in the matter. At the same time we would like to identify the most important criterions that will allow the user, regardless that he is or not an administrator, a public clerk or a judge, to delimit the legal behavior of the state’s institutions from the power excess. Within this context, we appreciate that the principle of proportionality represents such a criterion. The proportionality is a legal principle of the law, but at the same time it is a principle of the constitutional law and of other law branches. It expresses clearly the idea of balance, reasonability but also of adjusting the measures ordered by the state’s authorities to the situation in fact, respectively to the purpose for which they have been conceived. In our study we choose theoretical and jurisprudence arguments according to which the principle of proportionality can procedurally be determined and used to delimit the discretionary power and

  7. Low beta rigid mode stability criterion for an arbitrary Larmor radius plasma

    International Nuclear Information System (INIS)

    Berk, H.L.; Wong, H.V.

    1987-05-01

    The low beta flute interchange dispersion relation for rigid displacement perturbation of axisymmetric plasma equilibria with arbitrary Larmor radius particles and field line curvature, large compared to the plasma radius, is derived. The equilibrium particle orbits are characterized by two constants of motion, energy and angular momentum, and a third adiabatic invariant derived from the rapid radial motion. The Vlasov equation is integrated, assuming that the mode frequency, axial ''bounce'' frequency, and particle drift frequency are small compared to the cyclotron frequency, and it is demonstrated that the plasma response to a rigid perturbation has a universal character independent of Larmor radius. As a result the interchange instability is the same as that predicted from conventional MHD theory. However, a new prediction, more optimistic than earlier work, is found for the low density threshold of systems like Migma, which are disc-shaped, that is, the axial extent Δz is less than the radial extent r 0 . For Δz/sub r 0 / much less than 1, the stability criterion is determined by the total particle number. Whereas the older theory (Δz/sub r 0 / much greater than 1) predicted instability at about the densities achieved in actual Migma experiments, the present theory (Δz/sub r 0 / much less than 1) indicates that the experimental results were for plasmas with particle number below the interchange threshold

  8. Composing for Energy Engagement

    DEFF Research Database (Denmark)

    Schick, Lea

    carefully designed to be invisible, unnoticed, and un-engaging, a green transition will most likely make energy more visible and one of the major challenges proves to be how to re-design for more and for ‘the right’ kinds of energy engagement. This challenge is not only taken up by engineers and policy...... to be a dynamic and changeable ‘thing’ emerging through socio-technical relations and infrastructural environments. As the different cases ‘compose’ relations between people, energy, infrastructures, and environmental issues differently, they make possible specific kinds of engagement and not others...

  9. Measuring user engagement

    CERN Document Server

    Lalmas, Mounia; Yom-Tov, Elad

    2014-01-01

    User engagement refers to the quality of the user experience that emphasizes the positive aspects of interacting with an online application and, in particular, the desire to use that application longer and repeatedly. User engagement is a key concept in the design of online applications (whether for desktop, tablet or mobile), motivated by the observation that successful applications are not just used, but are engaged with. Users invest time, attention, and emotion in their use of technology, and seek to satisfy pragmatic and hedonic needs. Measurement is critical for evaluating whether online

  10. The ABCs of Student Engagement

    Science.gov (United States)

    Parsons, Seth A.; Nuland, Leila Richey; Parsons, Allison Ward

    2014-01-01

    Student engagement is an important consideration for teachers and administrators because it is explicitly associated with achievement. What the authors call the ABC's of engagement they outline as: Affective engagement, Behavioral engagement, and Cognitive engagement. They also present "Three Things Every Teacher Needs to Know about…

  11. Development of a stress-induced martensitic transformation criterion for a Cu–Al–Be polycrystalline shape memory alloy undergoing uniaxial tension

    International Nuclear Information System (INIS)

    García-Castillo, F.N.; Cortés-Pérez, J.; Amigó, V.; Sánchez-Arévalo, F.M.; Lara-Rodríguez, G.A.

    2015-01-01

    This study presents a criterion for predicting the martensitic variants (MVs) that appear during the stress-induced martensitic transformation (SIMT) in a polycrystalline sample of Cu–11.5% wt. Al–0.5% wt. Be under simple tension. Our criterion is based on crystallographic parameters, such as the crystal orientation and Schmid factor (SF). The displacement vector fields (DVFs) were obtained in the observation system by a mathematical model and were used to distort the boundary of a set of grains. From the DVF, the strain tensor for each grain was obtained, and the strain ratio (SR) in the observation system was calculated. Electron backscattering diffraction (EBSD) measurements were performed to determine the crystal orientation of the grains. The inverse SF was used to determine the in-plane stress transformation diagrams (STDs) for each studied grain. The combination of a balance criterion (BC) and STD provided a criterion that allowed us to predict the possible order of stress-induced MVs formed as a function of the crystal orientation and thermomechanical parameters of the shape memory alloy (SMA) with higher accuracy than when using the criteria separately. To validate our criteria, we tested other researchers’ published results. Our results were in agreement and were capable of predicting the stress-induced MVs in a polycrystalline SMA

  12. Determination of the initiation of ductile tearing in cracked branch pipes on the basis of a pre-determined criterion using small specimens

    International Nuclear Information System (INIS)

    Chapuliot, S.; Marie, S.

    1999-01-01

    This article describes an experimental and numerical study of the initiation conditions of ductile tearing in ferritic materials. An initial criterion J i is determined experimentally using a sufficiently thick CT specimen. The numerical and experimental aspects are then discussed for thinner CT specimen and a method is proposed for determining it in thin test samples. The local ductile tear initiation criterion, which was determined on the basis of 3D finite element calculations, was applied to a cracked branch pipe geometry subjected to out-of-plane bending to compare the load estimates at the start of propagation and the values measured during the test. The results of the comparison were highly satisfactory: the criterion is predictive. (orig.)

  13. P2-17: Individual Differences in Dynamic Criterion Shifts during Perceptual Decision Making

    Directory of Open Access Journals (Sweden)

    Issac Rhim

    2012-10-01

    Full Text Available Perceptual decision-making involves placing an optimal criterion on the axis of encoded sensory evidence to maximize outcomes for choices. Optimal criterion setting becomes critical particularly when neural representations of sensory inputs are noisy and feedbacks for perceptual choices vary over time in an unpredictable manner. Here we monitored time courses of decision criteria that are adopted by human subjects while abruptly shifting the criterion of stochastic feedback to perceptual choices with certain amounts in an unpredictable direction and at an unpredictable point of time. Subjects viewed a brief (0.3 s, thin (.07 deg annulus around the fixation and were forced to judge whether the annulus was smaller or larger than an unknown boundary. We estimated moment-to-moment criteria by fitting a cumulative Gaussian function to the data within a sliding window of trials that are locked to a shift in feedback criterion. Unpredictable shifts in feedback criterion successfully induced shifts in actual decision criterion towards an optimal criterion for many of subjects, but with time delay and amount of shifts varying across individual subjects. There were disproportionately more numbers of overshooters (reaching and then surpassing the optimal criterion required than undershooters (subpar reach, with a significant anti-correlation with sensory sensitivity. To find a mechanism that generates these individual differences, we developed a dynamic criterion learning model by modifying a reinforcement learning model, which assumes that a criterion is adjusted every trial by a weighted discrepancy between actual and expected rewards.

  14. Coupling Effect of Intruding Water and Inherent Gas on Coal Strength Based on the Improved (Mohr-Coulomb Failure Criterion

    Directory of Open Access Journals (Sweden)

    Yiyu Lu

    2016-11-01

    Full Text Available When employing hydraulic processes to increase gas drainage efficiency in underground coal mines, coal seams become a three-phase medium, containing water intruding into the coal pores with the inherent occurrence of gas. This can change the stress state of the coal and cause instability. This work studied the mechanical properties of coal containing water and gas and derived an appropriate failure criterion. Based on mixture theory of unsaturated porous media, the effective stress of coal, considering the interaction of water and gas, was analyzed, and the failure criterion established by combining this with the Mohr–Coulomb criterion. By introducing the stress factor of matrix suction and using fitted curves of experimentally determined matrix suction and moisture content, the relationships between coal strength, gas pressure, and moisture content were determined. To verify the established strength theory, a series of triaxial compression strength tests of coal containing water and gas were carried out on samples taken from the Songzao, Pingdingshan, and Tashan mines in China. The experimental results correlated well with the theoretical predictions. The results showed a linear decrease in the peak strength of coal with increasing gas pressure and an exponential reduction in peak strength with increasing moisture content. The strength theory of coal containing water and gas can become an important part of multiphase medium damage theory.

  15. The free growth criterion for grain initiation in TiB 2 inoculated γ-titanium aluminide based alloys

    Science.gov (United States)

    Gosslar, D.; Günther, R.

    2014-02-01

    γ-titanium aluminide (γ-TiAl) based alloys enable for the design of light-weight and high-temperature resistant engine components. This work centers on a numerical study of the condition for grain initiation during solidification of TiB2 inoculated γ-TiAl based alloys. Grain initiation is treated according to the so-called free growth criterion. This means that the free growth barrier for grain initiation is determined by the maximum interfacial mean curvature between a nucleus and the melt. The strategy presented in this paper relies on iteratively increasing the volume of a nucleus, which partially wets a hexagonal TiB2 crystal, minimizing the interfacial energy and calculating the corresponding interfacial curvature. The hereby obtained maximum curvature yields a scaling relation between the size of TiB2 crystals and the free growth barrier. Comparison to a prototypical TiB2 crystal in an as cast γ-TiAl based alloy allowed then to predict the free growth barrier prevailing under experimental conditions. The validity of the free growth criterion is discussed by an interfacial energy criterion.

  16. Constituting Public Engagement

    DEFF Research Database (Denmark)

    Davies, Sarah Rachael

    2013-01-01

    understanding of science to those of public engagement with science and technology (PEST), and the histories, or genealogies, of such models. Data from two qualitative studies-a case study of one of the United Kingdom'ssix Beacons for Public Engagement and a study of contract research staff-are used......This article uses data from two U.K. studies in order to explore the meanings attached to public engagement. It focuses on two issues of importance to contemporary discussions of science communication: the degree to which there has been a smooth transition, in practice, from models of public...... to characterize the ways in which U.K. academic communities understand PEST. It is argued that engagement is construed as multiple, relational, and outcomes oriented, with seven key outcomes ranging from better research to empowered individuals. These differences are traced to personal and professional...

  17. Engage Youth, Entrench Democracy

    International Development Research Centre (IDRC) Digital Library (Canada)

    and reluctant to engage in political action. But that is just one view. ... take positive action. For example ... thought. It seems, in fact, that they are keenly attentive to the conditions suffered by Brazil's .... proposed the fusion of the complementary.

  18. Student Engagement with Community

    Science.gov (United States)

    Knight-McKenna, Mary; Felten, Peter; Darby, Alexa

    2018-01-01

    Student engagement in the local community comes with both risks and rewards. This chapter explains the cognitive, behavioral, and affective outcomes of student learning in the community, along with noting the importance of preparation and reflection.

  19. Ignition criterion for heterogeneous energetic materials based on hotspot size-temperature threshold

    Science.gov (United States)

    Barua, A.; Kim, S.; Horie, Y.; Zhou, M.

    2013-02-01

    A criterion for the ignition of granular explosives (GXs) and polymer-bonded explosives (PBXs) under shock and non-shock loading is developed. The formulation is based on integration of a quantification of the distributions of the sizes and locations of hotspots in loading events using a cohesive finite element method (CFEM) developed recently and the characterization by Tarver et al. [C. M. Tarver et al., "Critical conditions for impact- and shock-induced hot spots in solid explosives," J. Phys. Chem. 100, 5794-5799 (1996)] of the critical size-temperature threshold of hotspots required for chemical ignition of solid explosives. The criterion, along with the CFEM capability to quantify the thermal-mechanical behavior of GXs and PBXs, allows the critical impact velocity for ignition, time to ignition, and critical input energy at ignition to be determined as functions of material composition, microstructure, and loading conditions. The applicability of the relation between the critical input energy (E) and impact velocity of James [H. R. James, "An extension to the critical energy criterion used to predict shock initiation thresholds," Propellants, Explos., Pyrotech. 21, 8-13 (1996)] for shock loading is examined, leading to a modified interpretation, which is sensitive to microstructure and loading condition. As an application, numerical studies are undertaken to evaluate the ignition threshold of granular high melting point eXplosive, octahydro-1,3,5,7-tetranitro-1,2,3,5-tetrazocine (HMX) and HMX/Estane PBX under loading with impact velocities up to 350 ms-1 and strain rates up to 105 s-1. Results show that, for the GX, the time to criticality (tc) is strongly influenced by initial porosity, but is insensitive to grain size. Analyses also lead to a quantification of the differences between the responses of the GXs and PBXs in terms of critical impact velocity for ignition, time to ignition, and critical input energy at ignition. Since the framework permits

  20. International Engagement Strategy

    Science.gov (United States)

    2017-06-14

    agreements and issue legal guidance on international law and intellectual property issues. ICPO will play an important role in realizing this vision and...the U.S. and its partners. INTERNATIONAL ENGAGEMENT VISION The directorate’s vision is for global S&T engagements to take advantage of emerging ideas...reduce risk to U.S. and partner countries, and increase their resilience; and Establish enduring relationships to provide access to

  1. The rules of engagement

    DEFF Research Database (Denmark)

    Davies, Sarah Rachael

    2013-01-01

    This article reflects on the “dialogic turn,” focusing on one analytical framework for understanding the wide range of processes that fall under the rubric of engagement. The notion of power-in-interaction is explored using a case study of informal dialogue, the Dana Centre, London. Using...... that imposed hierarchies are continually re-negotiated. In concluding I reflect on some implications of using power in the analysis of engagement....

  2. Measuring preschool learning engagement in the laboratory.

    Science.gov (United States)

    Halliday, Simone E; Calkins, Susan D; Leerkes, Esther M

    2018-03-01

    Learning engagement is a critical factor for academic achievement and successful school transitioning. However, current methods of assessing learning engagement in young children are limited to teacher report or classroom observation, which may limit the types of research questions one could assess about this construct. The current study investigated the validity of a novel assessment designed to measure behavioral learning engagement among young children in a standardized laboratory setting and examined how learning engagement in the laboratory relates to future classroom adjustment. Preschool-aged children (N = 278) participated in a learning-based Tangrams task and Story sequencing task and were observed based on seven behavioral indicators of engagement. Confirmatory factor analysis supported the construct validity for a behavioral engagement factor composed of six of the original behavioral indicators: attention to instructions, on-task behavior, enthusiasm/energy, persistence, monitoring progress/strategy use, and negative affect. Concurrent validity for this behavioral engagement factor was established through its associations with parent-reported mastery motivation and pre-academic skills in math and literacy measured in the laboratory, and predictive validity was demonstrated through its associations with teacher-reported classroom learning behaviors and performance in math and reading in kindergarten. These associations were found when behavioral engagement was observed during both the nonverbal task and the verbal story sequencing tasks and persisted even after controlling for child minority status, gender, and maternal education. Learning engagement in preschool appears to be successfully measurable in a laboratory setting. This finding has implications for future research on the mechanisms that support successful academic development. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Using Akaike's information theoretic criterion in mixed-effects modeling of pharmacokinetic data: a simulation study [version 3; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Erik Olofsen

    2015-07-01

    Full Text Available Akaike's information theoretic criterion for model discrimination (AIC is often stated to "overfit", i.e., it selects models with a higher dimension than the dimension of the model that generated the data. However, with experimental pharmacokinetic data it may not be possible to identify the correct model, because of the complexity of the processes governing drug disposition. Instead of trying to find the correct model, a more useful objective might be to minimize the prediction error of drug concentrations in subjects with unknown disposition characteristics. In that case, the AIC might be the selection criterion of choice. We performed Monte Carlo simulations using a model of pharmacokinetic data (a power function of time with the property that fits with common multi-exponential models can never be perfect - thus resembling the situation with real data. Prespecified models were fitted to simulated data sets, and AIC and AICc (the criterion with a correction for small sample sizes values were calculated and averaged. The average predictive performances of the models, quantified using simulated validation sets, were compared to the means of the AICs. The data for fits and validation consisted of 11 concentration measurements each obtained in 5 individuals, with three degrees of interindividual variability in the pharmacokinetic volume of distribution. Mean AICc corresponded very well, and better than mean AIC, with mean predictive performance. With increasing interindividual variability, there was a trend towards larger optimal models, but with respect to both lowest AICc and best predictive performance. Furthermore, it was observed that the mean square prediction error itself became less suitable as a validation criterion, and that a predictive performance measure should incorporate interindividual variability. This simulation study showed that, at least in a relatively simple mixed-effects modelling context with a set of prespecified models

  4. Student engagement and its relationship with early high school dropout.

    Science.gov (United States)

    Archambault, Isabelle; Janosz, Michel; Fallu, Jean-Sébastien; Pagani, Linda S

    2009-06-01

    Although the concept of school engagement figures prominently in most school dropout theories, there has been little empirical research conducted on its nature and course and, more importantly, the association with dropout. Information on the natural development of school engagement would greatly benefit those interested in preventing student alienation during adolescence. Using a longitudinal sample of 11,827 French-Canadian high school students, we tested behavioral, affective, cognitive indices of engagement both separately and as a global construct. We then assessed their contribution as prospective predictors of school dropout using factor analysis and structural equation modeling. Global engagement reliably predicted school dropout. Among its three specific dimensions, only behavioral engagement made a significant contribution in the prediction equation. Our findings confirm the robustness of the overall multidimensional construct of school engagement, which reflects both cognitive and psychosocial characteristics, and underscore the importance attributed to basic participation and compliance issues in reliably estimating risk of not completing basic schooling during adolescence.

  5. Validation of a Criterion for Cam Mechanisms Optimization Using Constraints upon Cam’s Curvature

    Directory of Open Access Journals (Sweden)

    Stelian Alaci

    2016-06-01

    Full Text Available For the mechanism with rotating cam and knife-edge follower, an optimization criterion by means of imposed constraints upon cam’s curvature is expressed in a special coordinate system. Thus, stating the optimization criterion in the coordinate system defined by the mechanisms constructive parameters -eccentricity and minimum follower’s stroke, a contour is obtained for any position of the mechanism. The optimization criterion assumes establishing the position of the characteristic point of the mechanism with respect to this contour. Fulfillment of optimization criterion assumes that the characteristic point is positioned in the same manner with respect to all contours. The optimization criterion is simplified when considering the envelope of the contours. The method is exemplified using two mechanisms, with the cams priori satisfying the criterion.

  6. Fluency: an aim in teaching and a criterion in assessment

    Directory of Open Access Journals (Sweden)

    Aud Marit Simensen

    2010-05-01

    Full Text Available This article investigates the concept ‘fluency’ from different perspectives. When fluency is an aim in teaching, a thorough comprehension of the concept among teachers is a prerequisite for appropriate planning of instruction, including the choice of appropriate classroom activities. When fluency is an assessment criterion, it is even more important that examiners have a shared perception of the concept. The present article starts by presenting common perceptions of the concept and goes on to explore some of the current research. Next, it provides a historical overview of the place of fluency in teaching theory and explains some of the preconditions for the inclusion of this concept among teaching objectives and assessment criteria. It will also, as an illustration, give an outline of the position of the concept over time in the Norwegian school system on the basis of an analysis of the relevant syllabuses. Finally, the article explicates the notion of language use as a complex cognitive skill and explores current method¬ological ideas about teaching towards fluency.

  7. The instability criterion for ideal and resistive MHD modes

    International Nuclear Information System (INIS)

    Li Ding

    2002-01-01

    The instability criterions for ideal helical perturbation and resistive kink/tearing modes are derived for arbitrary q profile. It is found that the q=1 mode can be unstable only within the q=1 surface in positive shear plasma. The instability region is enlarged as q 0 decreases and/or the current density is flatted. The instability can be completely suppressed in the reverse shear plasma for peaked, and flatted current profile. The q>1 modes are stable in the plasma core and marginal stable within the rational surface in the positive shear plasma. They become more stable in the plasma core and still marginal stable around the rational surface in the reversed shear plasma. It is shown that in the positive shear plasma, the q=1, 5/4, 4/3, 3/2 and 2/1 modes are in turn destabilized and becomes dominant unstable mode as q 0 increases for fixed q a . In the reversed shear plasma, all the q=1 and q>1 modes can be stable when q0 1 modes in turn becomes unstable as q 0 (>1) increases. At first, the inner branch is stable while the outer branch weakly unstable. Then, the both branches can become strongly unstable as q0 increases. (author)

  8. Robust Deep Network with Maximum Correntropy Criterion for Seizure Detection

    Directory of Open Access Journals (Sweden)

    Yu Qi

    2014-01-01

    Full Text Available Effective seizure detection from long-term EEG is highly important for seizure diagnosis. Existing methods usually design the feature and classifier individually, while little work has been done for the simultaneous optimization of the two parts. This work proposes a deep network to jointly learn a feature and a classifier so that they could help each other to make the whole system optimal. To deal with the challenge of the impulsive noises and outliers caused by EMG artifacts in EEG signals, we formulate a robust stacked autoencoder (R-SAE as a part of the network to learn an effective feature. In R-SAE, the maximum correntropy criterion (MCC is proposed to reduce the effect of noise/outliers. Unlike the mean square error (MSE, the output of the new kernel MCC increases more slowly than that of MSE when the input goes away from the center. Thus, the effect of those noises/outliers positioned far away from the center can be suppressed. The proposed method is evaluated on six patients of 33.6 hours of scalp EEG data. Our method achieves a sensitivity of 100% and a specificity of 99%, which is promising for clinical applications.

  9. A novel SURE-based criterion for parametric PSF estimation.

    Science.gov (United States)

    Xue, Feng; Blu, Thierry

    2015-02-01

    We propose an unbiased estimate of a filtered version of the mean squared error--the blur-SURE (Stein's unbiased risk estimate)--as a novel criterion for estimating an unknown point spread function (PSF) from the degraded image only. The PSF is obtained by minimizing this new objective functional over a family of Wiener processings. Based on this estimated blur kernel, we then perform nonblind deconvolution using our recently developed algorithm. The SURE-based framework is exemplified with a number of parametric PSF, involving a scaling factor that controls the blur size. A typical example of such parametrization is the Gaussian kernel. The experimental results demonstrate that minimizing the blur-SURE yields highly accurate estimates of the PSF parameters, which also result in a restoration quality that is very similar to the one obtained with the exact PSF, when plugged into our recent multi-Wiener SURE-LET deconvolution algorithm. The highly competitive results obtained outline the great potential of developing more powerful blind deconvolution algorithms based on SURE-like estimates.

  10. WPS criterion proposition based on experimental data base interpretation

    International Nuclear Information System (INIS)

    Chapuliot, S.; Izard, J.P.; Moinereau, D.; Marie, S.

    2011-01-01

    This article gives the background and the methodology developed to define a K J based criterion for brittle fracture of Reactor Pressure Vessel (RPV) submitted to Pressurized Thermal Shock (PTS), and taking into account Warm Pre Stressing effect (WPS). The first step of this methodology is the constitution of an experimental data base. This work was performed through bibliography and partnerships, and allows merging experimental results dealing with: -) Various ferritic steels; -) Various material states (as received, thermally aged, irradiated...); -) Various mode of fracture (cleavage, inter-granular, mixed mode); -) Various specimen geometry and size (CT, SENB, mock-ups); -) Various thermo-mechanical transients. Based on this experimental data base, a simple K J based limit is proposed and compared to experimental results. Parametric studies are performed in order to define the main parameters of the problem. Finally, a simple proposition based on a detailed analysis of tests results is performed. This proposition giving satisfactory results in every cases, it constitutes a good candidate for integration in French RSE-M code for in service assessment. (authors)

  11. Prediction of Underground Cavity Roof Collapse using the Hoek–Brown Failure Criterion

    DEFF Research Database (Denmark)

    Suchowerska, A. M.; Merifield, R. S.; Carter, J. P.

    2012-01-01

    Preventing roof collapse in underground cavities is a challenge to geotechnical engineering. In this study, three independent methods have been used to evaluate the roof collapse of underground rectangular cavities for a range of geometries and rock properties. The rock mass strength has been des...

  12. A Mean-Variance Criterion for Economic Model Predictive Control of Stochastic Linear Systems

    DEFF Research Database (Denmark)

    Sokoler, Leo Emil; Dammann, Bernd; Madsen, Henrik

    2014-01-01

    , the tractability of the resulting optimal control problem is addressed. We use a power management case study to compare different variations of the mean-variance strategy with EMPC based on the certainty equivalence principle. The certainty equivalence strategy is much more computationally efficient than the mean......-variance strategies, but it does not account for the variance of the uncertain parameters. Openloop simulations suggest that a single-stage mean-variance approach yields a significantly lower operating cost than the certainty equivalence strategy. In closed-loop, the single-stage formulation is overly conservative...... be modified to perform almost as well as the two-stage mean-variance formulation. Nevertheless, we argue that the mean-variance approach can be used both as a strategy for evaluating less computational demanding methods such as the certainty equivalence method, and as an individual control strategy when...

  13. Full-Scale Validation of a Comprehensive Criterion to Predict Fish-Friendliness of Pumps

    NARCIS (Netherlands)

    Krakers, L.A.; Kruyt, Nicolaas P.; Rutjes, H.A.

    2015-01-01

    Many pumping stations in drainage & irrigation applications are currently equipped with conventional (not fish friendly designed) pumps. Field tests have been performed [1] for several pump types of a certain size at certain pumping conditions to assess survival rates of fish passing through pumps.

  14. Predictive Power of Primary and Secondary School Success Criterion on Transition to Higher Education Examination Scores

    OpenAIRE

    Atilla ÖZDEMİR; Selahattin GELBAL

    2016-01-01

    It is seen that education has a significant effect that changes an individual’s life in our country in which education is a way of moving up the social ladder. In order to continue to a higher education program after graduating from high school, students have to succeed in transition to higher education examination. Thus, the entrance exam is an important factor to determine the future of the students. In our country, middle school grades and high school grade point average that is added to u...

  15. Criterion for the engineering performance of carbon materials under neutron irradiation

    International Nuclear Information System (INIS)

    Virgil'ev, Yu.S.

    2002-01-01

    The criterion for the engineering performance and substation of its applicability to the reactor graphite are proposed. The complex indicator, representing the ratio of strength limits by compression and bending is proposed as the above criterion, characterizing the graphite quality. The growth of this criterion indicates the accumulation of large heterogeneities microcracks of technological or radiation character. The decrease in this indicator testifies to the growth of small heterogeneities, and consequently to the increase in the graphite engineering performance [ru

  16. Knowledge processing and faculty engagement in multicultural university settings

    DEFF Research Database (Denmark)

    Selmer, Jan; Jonasson, Charlotte; Lauring, Jakob

    2014-01-01

    In educational studies much attention has been directed to engagement as a precondition for positive student outcomes. Very few studies, however, have focused on the engagement of the faculty members. This is a regrettable omission because engagement has been argued to lead to more satisfied, more...... – and faculty engagement. Our hypotheses are based on social learning theory and social exchange theory predicting that increased knowledge sharing activities could facilitate an environment in which faculty engagement thrives. In order to test our hypotheses we use multiple regression analysis. We assessed...... indicators of behavioural, cognitive and emotional engagement. Results showed consistent positive associations between group knowledge processing and all the studied faculty engagement indicators. Implications and suggestions for future research are discussed in detail....

  17. The impact of a total reward system of work engagement

    Directory of Open Access Journals (Sweden)

    Crystal Hoole

    2016-11-01

    Research purpose: The overall purpose of this study was to explore the relationship between total rewards and work engagement in a South African context and to determine which reward categories predict work engagement. The study further endeavoured to determine whether gender and age had a moderating effect on the relationship between total rewards and engagement. Motivation for the study: Statistics report that less than 30% of all working people are optimally engaged in their work. Considering that individuals spend more than a third of their lives at work committing themselves emotionally, physically and psychologically – research indicates that employees are no longer satisfied with traditional reward systems and want to feel valued and appreciated. Research approach, design and method: In this quantitative, cross-sectional research design using a non-probability convenience and purposive sampling strategy, 318 questionnaires were collected and analysed from financial institutions in Gauteng in which opinions were sought on the importance of different types of rewards structures and preferences, and how engaged they are in their workplace. The 17-item UWES and Nienaber total reward preference model were the chosen measuring instruments. Main findings: A small statistically significant correlation (r = 0.25; p < 0.05; small effect was found between total rewards and work engagement, and 12% of the variance of work engagement was explained. Only performance and career management significantly predicted work engagement. Practical/Managerial implications: Although small, the significant correlation between total rewards and work engagement implies that total rewards are important motivators for employees in the workplace. Of the total rewards scales tested, only performance and career management significantly predicted work engagement, suggesting that more research is needed. Organisations seeking to implement total reward strategies should pay specific

  18. The Criterion A problem revisited: controversies and challenges in defining and measuring psychological trauma.

    Science.gov (United States)

    Weathers, Frank W; Keane, Terence M

    2007-04-01

    The Criterion A problem in the field of traumatic stress refers to the stressor criterion for posttraumatic stress disorder (PTSD) and involves a number of fundamental issues regarding the definition and measurement of psychological trauma. These issues first emerged with the introduction of PTSD as a diagnostic category in the Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM-III; American Psychiatric Association, 1980) and continue to generate considerable controversy. In this article, the authors provide an update on the Criterion A problem, with particular emphasis on the evolution of the DSM definition of the stressor criterion and the ongoing debate regarding broad versus narrow conceptualizations of traumatic events.

  19. Slope Safety Factor Calculations With Non-Linear Yield Criterion Using Finite Elements

    DEFF Research Database (Denmark)

    Clausen, Johan; Damkilde, Lars

    2006-01-01

    The factor of safety for a slope is calculated with the finite element method using a non-linear yield criterion of the Hoek-Brown type. The parameters of the Hoek-Brown criterion are found from triaxial test data. Parameters of the linear Mohr-Coulomb criterion are calibrated to the same triaxial...... are carried out at much higher stress levels than present in a slope failure, this leads to the conclusion that the use of the non-linear criterion leads to a safer slope design...

  20. Suitability of the Yield Criterion in Numerical Simulation of Stretch Bending of Aluminum Extrusions

    International Nuclear Information System (INIS)

    Li, X.Q.; Zhou, X.B.; Wu, X.D.; Gao, H.Z.

    2005-01-01

    Stretch bending is commonly used to shape thin-walled extrusions in aerospace and automotive industries. The extrusions are pre-stretched and bent over rigid curved dies. Effective application of this process demands sufficient knowledge of how different parameters influence the final shape of the product. Numerical simulation is an effective approach to investigate these issues presently. However, the validity of simulation result depends strongly on a precise description of the mechanical behavior of the material. Due to crystallographic texture caused by the extrusion process, aluminium extrusions exhibit significant plastic anisotropy which need be described by advanced constitutive model. In this work stretch bending of aluminum extrusions is simulated by using different anisotropic criteria (Hill quadratic, Barlat three-parameter). The influence of two yield criteria on predicting maximum die force immediately before unloading, permanent sagging and vertical springback displacement in the middle section of extrusion are compared. Maximum die force and springback calculated by two yield criteria are found to be almost same. Permanent sagging is obviously underestimated by two yield criteria, however, prediction by Barlat three-parameter is closer to experiment than one of Hill quadratic yield criterion

  1. Development of a Model for Dynamic Recrystallization Consistent with the Second Derivative Criterion

    Directory of Open Access Journals (Sweden)

    Muhammad Imran

    2017-11-01

    Full Text Available Dynamic recrystallization (DRX processes are widely used in industrial hot working operations, not only to keep the forming forces low but also to control the microstructure and final properties of the workpiece. According to the second derivative criterion (SDC by Poliak and Jonas, the onset of DRX can be detected from an inflection point in the strain-hardening rate as a function of flow stress. Various models are available that can predict the evolution of flow stress from incipient plastic flow up to steady-state deformation in the presence of DRX. Some of these models have been implemented into finite element codes and are widely used for the design of metal forming processes, but their consistency with the SDC has not been investigated. This work identifies three sources of inconsistencies that models for DRX may exhibit. For a consistent modeling of the DRX kinetics, a new strain-hardening model for the hardening stages III to IV is proposed and combined with consistent recrystallization kinetics. The model is devised in the Kocks-Mecking space based on characteristic transition in the strain-hardening rate. A linear variation of the transition and inflection points is observed for alloy 800H at all tested temperatures and strain rates. The comparison of experimental and model results shows that the model is able to follow the course of the strain-hardening rate very precisely, such that highly accurate flow stress predictions are obtained.

  2. Fracture criterion for brittle materials based on statistical cells of finite volume

    International Nuclear Information System (INIS)

    Cords, H.; Kleist, G.; Zimmermann, R.

    1986-06-01

    An analytical consideration of the Weibull Statistical Analysis of brittle materials established the necessity of including one additional material constant for a more comprehensive description of the failure behaviour. The Weibull analysis is restricted to infinitesimal volume elements in consequence of the differential calculus applied. It was found that infinitesimally small elements are in conflict with the basic statistical assumption and that the differential calculus is not needed in fact since nowadays most of the stress analyses are based on finite element calculations, and these are most suitable for a subsequent statistical analysis of strength. The size of a finite statistical cell has been introduced as the third material parameter. It should represent the minimum volume containing all statistical features of the material such as distribution of pores, flaws and grains. The new approach also contains a unique treatment of failure under multiaxial stresses. The quantity responsible for failure under multiaxial stresses is introduced as a modified strain energy. Sixteen different tensile specimens including CT-specimens have been investigated experimentally and analyzed with the probabilistic fracture criterion. As a result it can be stated that the failure rates of all types of specimens made from three different grades of graphite are predictable. The accuracy of the prediction is one standard deviation. (orig.) [de

  3. Emotional intelligence: an admission criterion alternative to cumulative grade point averages for prelicensure students.

    Science.gov (United States)

    Jones-Schenk, Jan; Harper, Mary G

    2014-03-01

    Predicting potential student success is of great interest to nursing educators and academic administrators alike. Cumulative grade point average (CGPA) has traditionally been used to screen nursing program candidates, but CGPA itself has shown to have no statistically significant predictive value and may in fact screen out individuals who possess social intelligence attributes that are essential for success in nursing practice. The purpose of this study is to determine if students whose emotional intelligence characteristics meet or exceed those of successful staff nurses are more likely to be successful in a baccalaureate nursing program. A descriptive, correlational design was used to compare the emotional intelligence attributes of 116 potential nursing students and 42 successful staff nurses using the Emotional Quotient Inventory (EQ-i). Nursing students who remained in the nursing program were found to have significantly higher levels of total emotional intelligence, interpersonal capacity, and stress tolerance. Students who dropped from the nursing program were not significantly different from successful staff nurses in terms of emotional intelligence. Emotional intelligence presents a compelling adjunct to current selection criteria for nursing students. However, the lack of research prevents widespread adoption of this criterion. This study suggests that students with higher levels of emotional intelligence, particularly intrapersonal capacity and stress tolerance, are more likely to be successful in a baccalaureate nursing program than students with lower levels. Further research is needed to determine the usefulness of EI as a predictor of student success in nursing programs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Meaningful work, work engagement and organisational commitment

    Directory of Open Access Journals (Sweden)

    Madelyn Geldenhuys

    2014-03-01

    Research purpose: The aim of the study was to investigate the relationships amongst psychological meaningfulness, work engagement and organisational commitment and to test for a possible mediation effect of work engagement on the relationship between psychological meaningfulness and organisational commitment. Motivation for the study: Managers have to rethink ways of improving productivity and performance at work, due to the diverse, and in some instances escalating, needs of employees (e.g. financial support to uphold their interest in and enjoyment of working. Research approach, design and method: A quantitative approach was employed to gather the data for the study, utilising a cross-sectional survey design. The sample (n = 415 consisted of working employees from various companies and positions in Gauteng, South Africa. Main findings: The results confirmed a positive relationship between psychological meaningfulness, work engagement and organisational commitment. Further, psychological meaningfulness predicts work engagement, whilst psychological meaningfulness and work engagement predict organisational commitment. Practical/managerial implications: Employers identifying their employees’ commitment patterns and mapping out strategies for enhancing those that are relevant to organisational goals will yield positive work outcomes (e.g. employees who are creative, seek growth or challenges for themselves. Contribution/value-add: This study contributes to the literature through highlighting the impact that meaningful work has on sustaining employee commitment to the organisation.

  5. Coping and work engagement in selected South African organisations

    Directory of Open Access Journals (Sweden)

    Sebastiaan Rothmann

    2011-10-01

    Research purpose: The objective of this study was to investigate the relationship between coping strategies and work engagement in three occupational groups in South Africa. Motivation for the study: There is little understanding of the relationship between effective forms of coping and positive outcomes (like work engagement. Research design, approach and method: The researchers used a survey design. They drew random and stratified samples (N = 3178 from three occupational groups. These were technical employees in an electricity provider, professional and enrolled nurses and police officers. They administered the Coping Orientations to the Problems Experienced (COPE and the Utrecht Work Engagement Scale (UWES. Main findings: The results showed that there was a statistically significant relationship between work engagement, problem-focused coping, positive reinterpretation and growth. In the nursing sample, high problem-focused coping, low avoidance and low ventilation of emotions predicted work engagement best. In the police sample, four coping strategies (problem-focused coping, seeking social support, turning to religion and low ventilation of emotions predicted work engagement best. In the technician sample, problem-focused coping and low ventilation of emotions predicted work engagement best. Practical/managerial implications: Organisations should consider employees’ coping strategies when they introduce interventions to improve work engagement. Contribution/value-add: This study contributes to the knowledge about the relationship between coping strategies and work engagement in South African organisations.

  6. Student Engagement and Classroom Variables in Improving Mathematics Achievement

    Science.gov (United States)

    Park, So-Young

    2005-01-01

    The study explored how much student engagement and classroom variables predicted student achievement in mathematics. Since students were nested within a classroom, hierarchical linear modeling (HLM) was employed for the analysis. The results indicated that student engagement had positive effects on student academic growth per month in math after…

  7. Engaging With Reality

    DEFF Research Database (Denmark)

    Bondebjerg, Ib

    to engage us with reality. Engaging with Reality investigates some of the major global themes as they are reflected in documentaries from the USA, UK and Denmark. Engaging with Reality is a contribution to comparative, transnational studies of documentary in contemporary media culture. By comparing......Documentaries play an important role in the increasingly global media culture that has been developing over the last few decades. Despite its many different forms and genres, all documentaries claim a special relation to the way things are in the world, and they each attempt in their own way...... documentaries in three different countries dealing with the same global themes, the book contributes to a broader and deeper understanding of our global media culture. The book deals with documentaries as part of a new form of cosmopolitan narratives, as part of new, global forms of social imagination...

  8. Ginzburg criterion for ionic fluids: the effect of Coulomb interactions.

    Science.gov (United States)

    Patsahan, O

    2013-08-01

    The effect of the Coulomb interactions on the crossover between mean-field and Ising critical behavior in ionic fluids is studied using the Ginzburg criterion. We consider the charge-asymmetric primitive model supplemented by short-range attractive interactions in the vicinity of the gas-liquid critical point. The model without Coulomb interactions exhibiting typical Ising critical behavior is used to calibrate the Ginzburg temperature of the systems comprising electrostatic interactions. Using the collective variables method, we derive a microscopic-based effective Hamiltonian for the full model. We obtain explicit expressions for all the relevant Hamiltonian coefficients within the framework of the same approximation, i.e., the one-loop approximation. Then we consistently calculate the reduced Ginzburg temperature t(G) for both the purely Coulombic model (a restricted primitive model) and the purely nonionic model (a hard-sphere square-well model) as well as for the model parameters ranging between these two limiting cases. Contrary to the previous theoretical estimates, we obtain the reduced Ginzburg temperature for the purely Coulombic model to be about 20 times smaller than for the nonionic model. For the full model including both short-range and long-range interactions, we show that t(G) approaches the value found for the purely Coulombic model when the strength of the Coulomb interactions becomes sufficiently large. Our results suggest a key role of Coulomb interactions in the crossover behavior observed experimentally in ionic fluids as well as confirm the Ising-like criticality in the Coulomb-dominated ionic systems.

  9. Engagement through communication

    DEFF Research Database (Denmark)

    Lykke, Marianne

    2018-01-01

    In this chapter, we work from the assumption that university engagement can be fostered by addressing the dissemination of scientific knowledge as a communication process, and we explore how university engagement can be encouraged through the communication of scientific knowledge to SMEs (small...... and potentials) in relation to scientific knowledge, which must be taken into account in attempts to communicate scientific knowledge to SMEs. Based on this analysis, we discuss solutions and outline some communicative principles that can contribute with a solution-oriented perspective on how communicating...

  10. Public Engagement with Science

    DEFF Research Database (Denmark)

    Irwin, Alan

    2014-01-01

    ). The ‘deficit theory’ which still today characterize many scientific activities that address citizen can be criticized for ‘one-way communication’, ‘sanctity of expertise’, and treatment of the publics as ‘homogeneous’. When arguing for the need for public engagement with science it is question about...... for dialogue exercises look microscopic against the backdrop of global science and its governance. Maybe it has been over-promised what such public engagement exercises can deliver. We can safely conclude that, despite all the ‘from deficit to democracy’ talk, no such easy shift has been made. At best, partial...

  11. The Engagement Gap

    DEFF Research Database (Denmark)

    Tartari, Valentina; Salter, Ammon

    2015-01-01

    In recent years, the debate about the marginality of women in academic science has been extended to academics’ engagement with industry and their commercial efforts. Analyzing multi-source data for a large sample of UK physical and engineering scientists and employing a matching technique...... the presence of women in the local work setting and their wider discipline, and the institutional support for women’s careers in their organization. We explore the implications of these findings for policies to support women’s scientific and technical careers and engagement with industry....

  12. Engaging in Work Even When It Is Meaningless: Positive Affective Disposition and Meaningful Work Interact in Relation to Work Engagement

    Science.gov (United States)

    Steger, Michael F.; Littman-Ovadia, Hadassah; Miller, Michal; Menger, Lauren; Rothmann, Sebastiaan

    2013-01-01

    The central aim of the present study was to assess the predictive value of affective disposition and meaningful work on employee engagement. Specifically, it was proposed that meaningful work moderates the relationship between affective disposition and engagement. Questionnaires were completed by 252 white-collar employees, working in a variety of…

  13. National Guard Engagement in the Pacific: No Threat to Security

    National Research Council Canada - National Science Library

    Bour, Mark

    2002-01-01

    ... there. It predicts likely responses from non-participants and defends the program against critics who argue that engagement activities draw personnel and resources away from primary war fighting objectives...

  14. Evidence for the Criterion Validity and Clinical Utility of the Pathological Narcissism Inventory

    Science.gov (United States)

    Thomas, Katherine M.; Wright, Aidan G. C.; Lukowitsky, Mark R.; Donnellan, M. Brent; Hopwood, Christopher J.

    2012-01-01

    In this study, the authors evaluated aspects of criterion validity and clinical utility of the grandiosity and vulnerability components of the Pathological Narcissism Inventory (PNI) using two undergraduate samples (N = 299 and 500). Criterion validity was assessed by evaluating the correlations of narcissistic grandiosity and narcissistic…

  15. The Bohm Criterion for Radiofrequency Discharges - a Numerical Verification Based on Poisson Equation

    NARCIS (Netherlands)

    Meijer, P. M.; W. J. Goedheer,

    1993-01-01

    Recently it was shown that, by using the analysis of electrostatic waves entering the plasma-sheath edge, the direct-current (dc) Bohm criterion also holds for discharges under radio-frequency (rf) conditions. In this paper, the influence of Bohm's criterion on the sheath characteristics for

  16. A Controlled Evaluation of the Distress Criterion for Binge Eating Disorder

    Science.gov (United States)

    Grilo, Carlos M.; White, Marney A.

    2011-01-01

    Objective: Research has examined various aspects of the validity of the research criteria for binge eating disorder (BED) but has yet to evaluate the utility of Criterion C, "marked distress about binge eating." This study examined the significance of the marked distress criterion for BED using 2 complementary comparison groups. Method:…

  17. Elaboration of generalized criterion for zonality determination of the Chernobyl' NPP working spaces

    International Nuclear Information System (INIS)

    Simakov, A.V.; Bad'in, V.I.; Nosovskij, A.V.

    1992-01-01

    Analysis of the features of radioactive dose rating, regularities of their formation and dosimetry allows suggesting generalized criterion for assess zonality of compartments and territories, combining all factors and their action on operators. This criterion may be used during design of the new objects, development of programs and pursuance of work on removal of atomic power plants from operation. 6 refs.; 1 fig

  18. Elitism, Sharing and Ranking Choices in Evolutionary Multi-Criterion Optimisation

    OpenAIRE

    Pursehouse, R.C.; Fleming, P.J.

    2002-01-01

    Elitism and sharing are two mechanisms that are believed to improve the performance of an evolutionary multi-criterion optimiser. The relative performance of of the two most popular ranking strategies is largely unknown. Using a new empirical inquiry framework, this report studies the effect of elitism, sharing and ranking design choices using a benchmark suite of two-criterion problems.........

  19. A new risk-based screening criterion for treatment-demanding retinopathy of prematurity in Denmark

    DEFF Research Database (Denmark)

    Slidsborg, Carina; Forman, Julie Lyng; Rasmussen, Steen Christian

    2011-01-01

    The aim of this study was to uncover the most effective and safe criterion to implement for retinopathy of prematurity screening in Denmark.......The aim of this study was to uncover the most effective and safe criterion to implement for retinopathy of prematurity screening in Denmark....

  20. Characteristics of Criterion-Referenced Instruments: Implications for Materials Selection for the Learning Disabled.

    Science.gov (United States)

    Blasi, Joyce F.

    Discussed are characteristics of criterion referenced reading tests for use with learning disabled (LD) children, and analyzed are the Basic Educational Skills Inventory (BESI), the Prescriptive Reading Inventory (PRI), and the Cooper-McGuire Diagnostic Work-Analysis Test (CooperMcGuire). Criterion referenced tests are defined; and problems in…

  1. An Integrated Pruning Criterion for Ensemble Learning Based on Classification Accuracy and Diversity

    DEFF Research Database (Denmark)

    Fu, Bin; Wang, Zhihai; Pan, Rong

    2013-01-01

    be further considered while designing a pruning criterion is presented, and then an effective definition of diversity is proposed. The experimental results have validated that the given pruning criterion could single out the subset of classifiers that show better performance in the process of hill...

  2. Effects of Mastery Criterion on the Emergence of Derived Equivalence Relations

    Science.gov (United States)

    Fienup, Daniel M.; Brodsky, Julia

    2017-01-01

    In this study, we manipulated mastery criterion form (rolling or block) and stringency (across 6 or 12 trials) and measured the emergence of derived relations. College students learned neuroanatomy equivalence classes and experienced one of two rolling mastery criteria (6 or 12 consecutive correct responses) or a block mastery criterion (12 trials…

  3. Energy-efficient induction motors designing with application of a modified criterion of reduced costs

    Directory of Open Access Journals (Sweden)

    V.S. Petrushin

    2014-03-01

    Full Text Available The paper introduces a modified criterion of reduced costs that employs coefficients of operation significance and priority of ohmic loss accounting to allow matching maximum efficiency with minimum reduced costs. Impact of the inflation factor on the criterion of reduced costs is analyzed.

  4. The New DSM-5 Impairment Criterion: A Challenge to Early Autism Spectrum Disorder Diagnosis?

    Science.gov (United States)

    Zander, Eric; Bölte, Sven

    2015-01-01

    The possible effect of the DSM-5 impairment criterion on diagnosing autism spectrum disorder (ASD) in young children was examined in 127 children aged 20-47 months with a DSM-IV-TR clinical consensus diagnosis of ASD. The composite score of the Vineland Adaptive Behavior Scales (VABS) served as a proxy for the DSM-5 impairment criterion. When…

  5. University student’s engagement: development of the University Student Engagement Inventory (USEI

    Directory of Open Access Journals (Sweden)

    João Maroco

    2016-01-01

    Full Text Available Abstract Student engagement is a key factor in academic achievement and degree completion, though there is much debate about the operationalization and dimensionality of this construct. The goal of this paper is to describe the development of an psycho-educational oriented measure – the University Student Engagement Inventory (USEI. This measure draws on the conceptualization of engagement as a multidimensional construct, including cognitive, behavioural and emotional engagement. Participants were 609 Portuguese University students (67 % female majoring in Social Sciences, Biological Sciences or Engineering and Exact Sciences. The content, construct and predictive validity, and reliability of the USEI were tested. The validated USEI was composed of 15 items, and supported the tri-factorial structure of student engagement. We documented evidence of adequate reliability, factorial, convergent and discriminant validities. USEI’s concurrent validity, with the Utrecht Work Engagement Scale-Student Survey, and the predictive validity for self-reported academic achievement and intention to dropout from school were also observed.

  6. Does the Lowest Bid Price Evaluation Criterion Make for a More Efficient Public Procurement Selection Criterion? (Case of the Czech Republic

    Directory of Open Access Journals (Sweden)

    Ochrana František

    2015-06-01

    Full Text Available Through the institute of public procurement a considerable volume of financial resources is allocated. It is therefore in the interest of contracting entities to seek ways of how to achieve an efficient allocation of resources. Some public contract-awarding entities, along with some public-administration authorities in the Czech Republic, believe that the use of a single evaluation criterion (the lowest bid price results in a more efficient tender for a public contract. It was found that contracting entities in the Czech Republic strongly prefer to use the lowest bid price criterion. Within the examined sample, 86.5 % of public procurements were evaluated this way. The analysis of the examined sample of public contracts proved that the choice of an evaluation criterion, even the preference of the lowest bid price criterion, does not have any obvious impact on the final cost of a public contract. The study concludes that it is inappropriate to prefer the criterion of the lowest bid price within the evaluation of public contracts that are characterised by their complexity (including public contracts for construction works and public service contracts. The findings of the Supreme Audit Office related to the inspection of public contracts indicate that when using the lowest bid price as an evaluation criterion, a public contract may indeed be tendered with the lowest bid price, but not necessarily the best offer in terms of supplied quality. It is therefore not appropriate to use the lowest bid price evaluation criterion to such an extent for the purpose of evaluating work and services. Any improvement to this situation requires a corresponding amendment to the Law on Public Contracts and mainly a radical change in the attitude of the Office for the Protection of Competition towards proposed changes, as indicated within the conclusions and recommendations proposed by this study.

  7. Staying Engaged: Knowledge and Research Needs in Student Engagement

    Science.gov (United States)

    Wang, Ming-Te; Degol, Jessica

    2016-01-01

    In this article, we review knowledge about student engagement and look ahead to the future of study in this area. We begin by describing how researchers in the field define and study student engagement. In particular, we describe the levels, contexts, and dimensions that constitute the measurement of engagement, summarize the contexts that shape engagement and the outcomes that result from it, and articulate person-centered approaches for analyzing engagement. We conclude by addressing limitations to the research and providing recommendations for study. Specifically, we point to the importance of incorporating more work on how learning-related emotions, personality characteristics, prior learning experiences, shared values across contexts, and engagement in nonacademic activities influence individual differences in student engagement. We also stress the need to improve our understanding of the nuances involved in developing engagement over time by incorporating more extensive longitudinal analyses, intervention trials, research on affective neuroscience, and interactions among levels and dimensions of engagement. PMID:27087833

  8. Civic Engagement and Associationalism

    DEFF Research Database (Denmark)

    Alexander, Damon Timothy; Barraket, Jo; Lewis, Jenny

    2012-01-01

    use a large survey to explore these questions empirically by focusing on the membership patterns and civic engagement practices of 4,001 citizens drawn from eight suburbs across Greater Melbourne, Australia. Our findings indicate that, while associational intensity is positively related to civic...

  9. The Player Engagement Process

    DEFF Research Database (Denmark)

    Schoenau-Fog, Henrik

    2011-01-01

    , categories and triggers involved in this process. By applying grounded theory to the analysis of the responses, a process-oriented player engagement framework was developed and four main components consisting of objectives, activities, accomplishments and affects as well as the corresponding categories...

  10. Tools of Engagement

    Science.gov (United States)

    Allen, Elizabeth

    2012-01-01

    Alumni relations professionals need a method of measuring alumni engagement, including giving, that goes beyond counting event attendees and the number of Twitter followers. Social media are changing the way things have been done within the alumni relations profession, but that does not mean that people throw out everything they have done in the…

  11. Mellem engagement og afmagt

    DEFF Research Database (Denmark)

    Ahrenkiel, Annegrethe; Nielsen, Birger Steen; Schmidt, Camilla

    Bogen præsenterer resultaterne fra udviklings- og forskningsprojektet "BUPL-tillidsrepræsentanten. Nye udfordringer - nye svar". Den giver et fyldigt indblik i tillidsrepræsentanternes arbejde, deres engagement, vanskeligheder og forhåbninger. På baggrund af et større værkstedsarbejde fremlægges...

  12. Engaging with users

    DEFF Research Database (Denmark)

    Riisberg, Vibeke; Bang, Anne Louise

    with the biggest sense organ – our skin. Thus, the aim of our research is to develop new dialogue tools for teaching fashion and textile students in order to stimulate new ways of thinking and engaging with users. By developing and employing participatory design methods in the field of fashion and textiles, we...

  13. Reframing Global Engagement.

    NARCIS (Netherlands)

    van der Wende, M.C.

    2017-01-01

    Globalization has strongly influenced higher education during the last decades. As in many other sectors, this has generated contradictory outcomes. Higher education has opened up to the world and become more engaged at the global level. But how will this process continue with the current backlash

  14. Engaging with Islamic Patterns

    Science.gov (United States)

    Sugarman, Ian

    2012-01-01

    Islamic patterns were a regular feature in mathematics classrooms, and probably still feature in many wall displays. However, as part of the learning process, these ancient designs appear to have lost any significant contemporary appeal. Here, the power of software is engaged to bring the construction of Islamic type patterns up to date. Forget…

  15. The Engagement Gap

    DEFF Research Database (Denmark)

    Tartari, Valentina; Salter, Ammon

    2015-01-01

    In recent years, the debate about the marginality of women in academic science has been extended to academics’ engagement with industry and their commercial efforts. Analyzing multi-source data for a large sample of UK physical and engineering scientists and employing a matching technique, this s...

  16. Analytics for Customer Engagement

    NARCIS (Netherlands)

    Bijmolt, Tammo H. A.; Leeflang, Peter S. H.; Block, Frank; Eisenbeiss, Maik; Hardie, Bruce G. S.; Lemmens, Aurelie; Saffert, Peter

    In this article, we discuss the state of the art of models for customer engagement and the problems that are inherent to calibrating and implementing these models. The authors first provide an overview of the data available for customer analytics and discuss recent developments. Next, the authors

  17. Music Researchers' Musical Engagement

    Science.gov (United States)

    Wollner, Clemens; Ginsborg, Jane; Williamon, Aaron

    2011-01-01

    There is an increasing awareness of the importance of reflexivity across various disciplines, which encourages researchers to scrutinize their research perspectives. In order to contextualize and reflect upon research in music, this study explores the musical background, current level of musical engagement and the listening habits of music…

  18. Engaging stakeholder networks

    Energy Technology Data Exchange (ETDEWEB)

    Svendsen, A. [CoreRelation Consulting Inc., Delta, BC (Canada)]|[Simon Fraser Univ., Burnaby, BC (Canada); Laberge, M. [Simon Fraser Univ., Burnaby, BC (Canada)

    2004-07-01

    Management philosophies concerning stakeholder engagement were reviewed. This presentation provided guidelines for managers working from a sustainability value creation framework who wish to develop more effective ways to engage with stakeholders and high stakes issues that cross political, social and organizational boundaries. It was suggested that conflicts over resources, the demand for participation and the increasing power of Non-Governmental Organizations have all contributed to the increased need for stakeholder engagement. A review of different types of stakeholders was provided. Earlier strategies of managing stakeholders were examined, in which externalities such as environmental cost were not accounted for. By contrast, the emerging management philosophy presented here stressed a recognition that long term survival relied on the good health of external and internal environments. Core business strategies were discussed with reference to core values. It was suggested that a longer term focus, inclusiveness, and integration were beneficial to businesses as a whole. A case study of Clayoquot Sound was presented. The concept of social capital was examined. Individual and collective learning were evaluated. A model for engaging stakeholder networks was presented as well as a step by step procedural guide, which included the creation of a solid foundation; organizational alignment; strategy; the importance of asking questions; trust building; evaluation; and renewal. Challenges to stakeholder engagement included finding resources; ensuring consistency; patience; a tendency in business to measure success in short term payoffs; and maintaining a stakeholder perspective. It was concluded that the benefits of a sustainability value creation framework for businesses far outweighed any initial disadvantages. refs., tabs., figs.

  19. The adolescents’ school engagement: Assessment of its dimensions

    Directory of Open Access Journals (Sweden)

    José Manuel TOMÁS

    2016-06-01

    Full Text Available A topic that in the last years is getting relevance in school and students research is school engagement. This topic has been related, among other important constructs, with burnout of teachers and students, school performance, satisfaction with the school, behavioral disruption, goal orientation and motivational climate in the classroom, students-teachers relationships, and life satisfaction of the students. School engagement may be defined as the participation of the student in academic achievements, and it is understood as a multidimensional construct. The most repeated typology of dimensions recognizes three specific and overlapping dimensions: cognitive, behavioral, and emotional (affective. Frequently, education professionals have reported the lack of instruments to measure some students’ characteristics and psychosocial and behavioral variables in the classroom, as it is the case of school engagement. Recently, a fourth new dimension, personal agency, has been proposed (Reeve and Tseng, 2011. Veiga (2013 has been the first to present a self-report instrument, in Portuguese, to measure these four components, the Student Engagement Scale-4 dimensions (ses-4ds. Taken all this into account, the aim of this research was to study the reliability and validity of the aforementioned scale in two versions, Spanish and Portuguese, in large samples from the Dominican Republic and Angola. Results have shown a clear factor structure (after deleting two items, and adequate criterion-related and nomological validity. Accordingly, the ses-4d scale was considered a valid instrument to be applied in studies measuring school engagement of teenagers. 

  20. Experimental and finite element analysis of fracture criterion in ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Birla Institute of Technology and Science, Pilani 333 031, India. 2 Research and ... The prevention of failure in stressed structural components currently ..... propagates. In the present work, a similar principle is extended to predict fracture limits using ... ASTM 1991 American Society for Testing and Materials (ASTM). E399-91 ...

  1. Criterion validity and reliability of a smartphone delivered sub-maximal fitness test for people with type 2 diabetes

    DEFF Research Database (Denmark)

    Brinklov, Cecilie Fau; Thorsen, Ida Kær; Karstoft, Kristian

    2016-01-01

    Background: Prevention of multi-morbidities following non-communicable diseases requires a systematic registration of adverse modifiable risk factors, including low physical fitness. The aim of the study was to establish criterion validity and reliability of a smartphone app (InterWalk) delivered....... The algorithm was validated using leave-one-out cross validation. Test-retest reliability was tested in a subset of participants (N = 10). Results: The overall VO2peak prediction of the algorithm (R2) was 0.60 and 0.45 when the smartphone was placed in the pockets of the pants and jacket, respectively (p ... calorimetry and the acceleration (vector magnitude) from the smartphone was obtained. The vector magnitude was used to predict VO2peak along with the co-variates weight, height and sex. The validity of the algorithm was tested when the smartphone was placed in the right pocket of the pants or jacket...

  2. A Better Criterion for the Discharging Time in an RC Circuit

    Science.gov (United States)

    Lima, Fabio M. S.

    2015-01-01

    When all parts of an electric circuit are at the same potential, no electric current flows and it is said to be in equilibrium. Otherwise, a current will flow from the higher potential parts to the lower ones, as when we make contact between the plates of a charged capacitor. The resulting discharging process towards equilibrium is a common phenomenon in electricity labs, as well as a topic covered in introductory physics, but some questions are not answered, e.g., could we establish a good criterion for the "end" of the charge transfer process? If so, typically how long does it take for electric equilibrium to be reached? The absence of these questions in textbooks and lab manuals has bothered me since my own undergraduate studies because, as the usual theory, in which charge is treated as a continuous, rather than discrete, parameter, predicts an exponential decay for the charge stored in the capacitor, rigorously speaking we should wait an infinitely long time for finding a complete equilibrium.1 Fortunately, when teaching experimental physics last year, I was asked about these very questions, which motivated me to search for a simple answer that could be adopted universally for measuring the "lifetime" of any physical quantity that decays exponentially in time.

  3. Criterion validity of a Wechsler-III Scale Short Form in a sample of brazilian elderly.

    Science.gov (United States)

    Banhato, Eliane Ferreira Carvalho; Leite, Isabel Cristina Gonçalves; Guedes, Danielle Viveiros; Chaoubah, Alfredo

    2010-01-01

    Although a normative process, changes in cognitive functioning vary among older adults. The differential diagnosis between normal and pathological aging must be made early using psychometrically adequate measures. To assess the evidence of criterion validity of a Short Form (SF) of the Wechsler-III Scale containing eight subtests (SF8) by determining its sensitivity, specificity, positive and negative predictive values and cut-off points for Brazilian elderly from different age groups. 168 individuals, aged 60 years or above, living in the community or in an institution, were assigned to case and control groups, and investigated according to age range. Measures included a sociodemographic questionnaire, the Mini-Mental State Examination (MMSE), Verbal Fluency Test, Clock-Drawing Test and the SF8. More than two thirds of the sample was women (73.8%), mean age was 74.5 years (SD=8.9), mean education was 6.2 years (SD=4.8) and 40.5% were widows/widowers. In the total sample, the best cut-off point for the SF8 was 142 while cut offs among individuals aged 60 to 69 years, 70 to 79 years, and more than 80 years were 160, 129 and 129, respectively. The results demonstrated the importance of different cut-off points for different age ranges. Sensitivity and specificity values of the SF8 were sufficiently high to warrant the use of the SF8 as an instrument to identify cognitive impairment in the elderly.

  4. The derivation of a bistable criterion for double V-beam mechanisms

    International Nuclear Information System (INIS)

    Wu, Cho-Chun; Chen, Rongshun; Lin, Meng-Ju

    2013-01-01

    This study presents the theoretical derivation of the discriminant D as a structural and material criterion for determining whether bistability can occur in micromechanically bistable mechanisms. When D < 0, the mechanism displays bistable behavior if an appropriate force is applied to push the bistable mechanism, whereas when D > 0, bistable behavior cannot occur. The proposed V-beam bistable mechanism was successfully fabricated with various beam lengths and tilted angles. The experiments conducted in this study validated the theoretical study of bistability. A comparison of the theoretical solutions and experimental results shows good agreement. Results further show that to design a bistable V-beam mechanism, the tilted angle should be larger for the same beam length, whereas the beam length should be longer for the same tilted angle. The developed discriminant D can be used to predict if a bistable mechanism can achieve bistable behavior based on structural sizes and material properties. Consequently, researchers can reduce trial-and-error experiments when designing a bistable mechanism. A V-beam with a larger tilted angle of up to 5° was successfully fabricated to act as a bistable mechanism, compared to a 3.5° tilted angle in existing studies. Consequently, the proposed method has the advantages of shorter beam lengths and smaller device areas. (paper)

  5. Blasting Vibration Safety Criterion Analysis with Equivalent Elastic Boundary: Based on Accurate Loading Model

    Directory of Open Access Journals (Sweden)

    Qingwen Li

    2015-01-01

    Full Text Available In the tunnel and underground space engineering, the blasting wave will attenuate from shock wave to stress wave to elastic seismic wave in the host rock. Also, the host rock will form crushed zone, fractured zone, and elastic seismic zone under the blasting loading and waves. In this paper, an accurate mathematical dynamic loading model was built. And the crushed zone as well as fractured zone was considered as the blasting vibration source thus deducting the partial energy for cutting host rock. So this complicated dynamic problem of segmented differential blasting was regarded as an equivalent elastic boundary problem by taking advantage of Saint-Venant’s Theorem. At last, a 3D model in finite element software FLAC3D accepted the constitutive parameters, uniformly distributed mutative loading, and the cylindrical attenuation law to predict the velocity curves and effective tensile curves for calculating safety criterion formulas of surrounding rock and tunnel liner after verifying well with the in situ monitoring data.

  6. Genes, psychological traits and civic engagement

    Science.gov (United States)

    Dawes, Christopher T.; Settle, Jaime E.; Loewen, Peter John; McGue, Matt; Iacono, William G.

    2015-01-01

    Civic engagement is a classic example of a collective action problem: while civic participation improves life in the community as a whole, it is individually costly and thus there is an incentive to free ride on the actions of others. Yet, we observe significant inter-individual variation in the degree to which people are in fact civically engaged. Early accounts reconciling the theoretical prediction with empirical reality focused either on variation in individuals’ material resources or their attitudes, but recent work has turned to genetic differences between individuals. We show an underlying genetic contribution to an index of civic engagement (0.41), as well as for the individual acts of engagement of volunteering for community or public service activities (0.33), regularly contributing to charitable causes (0.28) and voting in elections (0.27). There are closer genetic relationships between donating and the other two activities; volunteering and voting are not genetically correlated. Further, we show that most of the correlation between civic engagement and both positive emotionality and verbal IQ can be attributed to genes that affect both traits. These results enrich our understanding of the way in which genetic variation may influence the wide range of collective action problems that individuals face in modern community life. PMID:26503688

  7. Exclusion as a Criterion for Selecting Socially Vulnerable Population Groups

    Directory of Open Access Journals (Sweden)

    Aleksandra Anatol’evna Shabunova

    2016-05-01

    Full Text Available The article considers theoretical aspects of a scientific research “The Mechanisms for Overcoming Mental Barriers of Inclusion of Socially Vulnerable Categories of the Population for the Purpose of Intensifying Modernization in the Regional Community” (RSF grant No. 16-18-00078. The authors analyze the essence of the category of “socially vulnerable groups” from the legal, economic and sociological perspectives. The paper shows that the economic approach that uses the criterion “the level of income and accumulated assets” when defining vulnerable population groups prevails in public administration practice. The legal field of the category based on the economic approach is defined by the concept of “the poor and socially unprotected categories of citizens”. With the help of the analysis of theoretical and methodological aspects of this issue, the authors show that these criteria are a necessary but not sufficient condition for classifying the population as being socially vulnerable. Foreign literature associates the phenomenon of vulnerability with the concept of risks, with the possibility of households responding to them and with the likelihood of losing the well-being (poverty theory; research areas related to the means of subsistence, etc.. The asset-based approaches relate vulnerability to the poverty that arises due to lack of access to tangible and intangible assets. Sociological theories presented by the concept of social exclusion pay much attention to the breakdown of social ties as a source of vulnerability. The essence of social exclusion consists in the inability of people to participate in important aspects of social life (in politics, labor markets, education and healthcare, cultural life, etc. though they have all the rights to do so. The difference between the concepts of exclusion and poverty is manifested in the displacement of emphasis from income inequality to limited access to rights. Social exclusion is

  8. Transnationalism and Civic Engagement

    DEFF Research Database (Denmark)

    Farah, Abdulkadir Osman

    . In order to surmount the dichotomy of essentialist versus no-essentialist frames, the epistemological approach instrumentalized in this work follows an emancipatory method critically engaging both approaches. Furthermore the book proposes a theoretical framework analytically connecting western and non......The question of population migration and Diaspora transnationalism in the age of globalization is an area of social sciences deserving much more attention than it has received. This book deals with the advent of new ideological currents based on an assumed “Clash of Civilizations” increasingly...... or modern, i.e. symbolizing modernity, urbanization and individualism). Finally this book empirically examines how a host country’s mobilizing, political and structural opportunities or lack of them influence transnational Diasporas’ civic engagement that often include the application of combined formal...

  9. Analytical Solution of Tunnel Surrounding Rock for Stress and Displacement Based on Lade–Duncan Criterion

    Directory of Open Access Journals (Sweden)

    MingZheng Zhu

    2018-01-01

    Full Text Available The deformation and failure of tunnel surrounding rock is the result of tunnel excavation disturbance and rock stress release. When the local stress of surrounding rock exceeds the elastic limit of rock mass, the plastic analysis of surrounding rock must be carried out to judge the stability of tunnel. In this study, the Lade–Duncan yield criterion is used to calculate the analytic solutions for the surrounding rock in a tunnel, and the radius and displacement of the plastic zone are deduced using an equilibrium equation. The plastic zone radius and displacement based on Lade–Duncan criterion and Mohr–Coulomb criterion were compared by using single-factor analysis method under the different internal friction angles, in situ stresses, and support resistances. The results show that the solutions of the radius and displacement of plastic zone calculated by the Lade–Duncan criterion are close to those of Mohr–Coulomb criterion under the high internal friction angle and support resistance or low in situ rock stress; however, the radius and displacement of the plastic zone calculated by the Lade–Duncan criterion are larger under normal circumstances, and the Lade–Duncan criterion is more applicable to the stability analysis of the surrounding rock in a tunnel.

  10. A Blocking Criterion for Self-Compacting Concrete

    DEFF Research Database (Denmark)

    Thrane, Lars Nyholm; Stang, Henrik; Geiker, Mette Rica

    2005-01-01

    To benefit from the full potential of Self-Compacting Concrete (SCC) prediction tools for the form filling ability of SCC are needed. This paper presents a theoretical concept for assessment of the blocking resistance of SCC. A critical concrete flow rate above which no blocking occurs...... is introduced. The critical flow rate takes into account the mix design, the rheological properties of the matrix and concrete, and the geometry of the flow domain....

  11. Collaborative engagement experiment (CEE)

    Science.gov (United States)

    Wade, Robert L.; Reames, Joseph M.

    2005-05-01

    Unmanned ground and air systems operating in collaboration have the potential to provide future Joint Forces a significant capability for operations in complex terrain. Ground and air collaborative engagements potentially offer force conservation, perform timely acquisition and dissemination of essential combat information, and can eliminate high value and time critical targets. These engagements can also add considerably to force survivability by reducing soldier and equipment exposure during critical operations. The Office of the Secretary of Defense, Joint Robotics Program (JRP) sponsored Collaborative Engagement Experiment (CEE) is a consolidation of separate Air Force, Army and Navy collaborative efforts to provide a Joint capability. The Air Force Research Laboratory (AFRL), Material and Manufacturing Directorate, Aerospace Expeditionary Force Division, Force Protection Branch (AFRLMLQF), The Army Aviation and Missile Research, Development and Engineering Center (AMRDEC) Joint Technology Center (JTC)/Systems Integration Laboratory (SIL), and the Space and Naval Warfare Systems Center-San Diego (SSC San Diego) are conducting technical research and proof of principle for an envisioned operational concept for extended range, three dimensional, collaborative operations between unmanned systems, with enhanced situational awareness for lethal operations in complex terrain. This program will assess information requirements and conduct experiments to identify and resolve technical risks for collaborative engagements using Unmanned Ground Vehicles (UGVs) and Unmanned Aerial Vehicles (UAVs). It will research, develop and physically integrate multiple unmanned systems and conduct live collaborative experiments. Modeling and Simulation systems will be upgraded to reflect engineering fidelity levels to greater understand technical challenges to operate as a team. This paper will provide an update of a multi-year program and will concentrate primarily on the JTC

  12. Frafald og engagement

    DEFF Research Database (Denmark)

    Jørgensen, Christian Helms; Pedersen, Lene Tanggaard; Nielsen, Klaus

    Denne rapport beskriver de første resultater fra den kvalitative del af et forskningsprojekt om frafald og fastholdelse i dansk erhvervsuddannelse finansieret af Det Strategiske Forskningsråd i perioden 2009-2012. Resultaterne bygger på de første elevinterview gennemført i efteråret 2009 og fokus...... fokuserer eksplicit på elevernes oplevelse af eget engagement eller mangel på samme på erhvervsskolernes grundforløb....

  13. Career Engagement: Bridging Career Counseling and Employee Engagement

    Science.gov (United States)

    Neault, Roberta A.; Pickerell, Deirdre A.

    2011-01-01

    In this article, the authors present a model of career engagement that helps bridge the gap between career counselors' focus on supporting individuals to find meaningful work and employers' desire for an engaged, productive, and committed workforce. They briefly review highlights of the employee engagement literature, introduce the Career…

  14. The Future of Student Engagement

    Science.gov (United States)

    Buskist, William; Groccia, James E.

    2018-01-01

    This chapter underscores the importance of conceptualizing student engagement as a responsibility shared by all members of the academy and describes how Groccia's multidimensional model can serve as blueprint for future thinking and research on student engagement.

  15. Operations of human resources engagement

    OpenAIRE

    Δημητρέλη, Αλεξάνδρα

    2017-01-01

    This current study, attempts to shed light on the relationship between HR Operations and employee engagement by testing the relationship empirically. More specifically, it looks at how employee engagement could be embedded into day-to-day human resources operations. Employee engagement is a topic that is repeatedly being discussed in most of the HR forums, articles and journals in the recent past. Employers recognize that truly engage and motivate employee’s produce impressive levels of in...

  16. Students' Engagement with Learning Technologies

    Science.gov (United States)

    Larkin, Derek; Huett, Kim C.

    2013-01-01

    This paper seeks to add to the discussion surrounding young adults' relationship and engagement with learning technologies, exploring whether they naturally engage with these technologies when the use of them is either compulsory or optional. We discuss our findings in relation to whether young people are truly engaging with technologies or…

  17. Engaging Stakeholders in Curriculum Development

    Science.gov (United States)

    Wood, Jo Nell

    2010-01-01

    This article investigates the importance of parent and community engagement in curriculum development, along with curriculum leadership, engaging stakeholders, and the importance of curriculum. Parent and community member engagement is examined in light of curriculum committee participation as reported by Missouri superintendents. Survey responses…

  18. Happiness Is the Way: Paths to Civic Engagement between Young Adulthood and Midlife

    Science.gov (United States)

    Fang, Shichen; Galambos, Nancy L.; Johnson, Matthew D.; Krahn, Harvey J.

    2018-01-01

    Directional associations between civic engagement and happiness were explored with longitudinal data from a community sample surveyed four times from age 22 to 43 (n = 690). Autoregressive cross-lagged models, controlling for cross-time stabilities in happiness and civic engagement, examined whether happiness predicted future civic engagement,…

  19. (No) Harm in Asking: Class, Acquired Cultural Capital, and Academic Engagement at an Elite University

    Science.gov (United States)

    Jack, Anthony Abraham

    2016-01-01

    How do undergraduates engage authority figures in college? Existing explanations predict class-based engagement strategies. Using in-depth interviews with 89 undergraduates at an elite university, I show how undergraduates with disparate precollege experiences differ in their orientations toward and strategies for engaging authority figures in…

  20. Consistency of test behaviour and individual difference in prescision of prediction

    NARCIS (Netherlands)

    Meijer, R.R.

    1998-01-01

    Ghiselli ((1956, 1960) argued that the precision of prediction on the basis of a test may vary for different individuals. To quantify the individual precision of prediction he compared the observed criterion scores with the expected criterion scores estimated on the basis of the total scores on a

  1. Strengthening stakeholder-engaged research and research on stakeholder engagement.

    Science.gov (United States)

    Ray, Kristin N; Miller, Elizabeth

    2017-06-01

    Stakeholder engagement is an emerging field with little evidence to inform best practices. Guidelines are needed to improve the quality of research on stakeholder engagement through more intentional planning, evaluation and reporting. We developed a preliminary framework for planning, evaluating and reporting stakeholder engagement, informed by published conceptual models and recommendations and then refined through our own stakeholder engagement experience. Our proposed exploratory framework highlights contexts and processes to be addressed in planning stakeholder engagement, and potential immediate, intermediate and long-term outcomes that warrant evaluation. We use this framework to illustrate both the minimum information needed for reporting stakeholder-engaged research and the comprehensive detail needed for reporting research on stakeholder engagement.

  2. Towards understanding causality between work engagement and psychological capital

    Directory of Open Access Journals (Sweden)

    Johannes J. de Waal

    2013-10-01

    Research purpose: The main aim of this study was to conceptualise and investigate the causal relationship and temporal order in the relationship between PsyCap and engagement by means of longitudinal data. Motivation for the study: The rationale for establishing the sequence of engagement and psychological capital lies in the fact that training interventions to enhance the organisational well-being of employees may need to be focused on either one or the other. Research design, approach and method: A longitudinal study with a cross-lagged panel design was conducted; data was gathered by means of a survey that was constructed for the purpose of the study. The survey contained the Utrecht Work Engagement Scale (UWES, and a measure of PsyCap. All employees within a chemical factory (N = 1003 were approached to provide data; 163 employees participated. Main findings: Results revealed that PsyCap at Time 1 (T1 did not significantly predict engagement at Time 2 (T2. Evidence does however exist that initial levels of employee engagement predict subsequent PsyCap. Practical/managerial implications: Results suggest that employee interventions aimed at protecting and fostering employee engagement may have implications for subsequent employee psychological capital. Contribution/value-add: As an empirical, longitudinal study to address the temporal order between PsyCap and work engagement, this study makes a contribution especially to theory, but also with practical implications by indicating that engagement precedes employee psychological capital.

  3. An advanced constitutive model in the sheet metal forming simulation: the Teodosiu microstructural model and the Cazacu Barlat yield criterion

    International Nuclear Information System (INIS)

    Alves, J.L.; Oliveira, M.C.; Menezes, L.F.

    2004-01-01

    Two constitutive models used to describe the plastic behavior of sheet metals in the numerical simulation of sheet metal forming process are studied: a recently proposed advanced constitutive model based on the Teodosiu microstructural model and the Cazacu Barlat yield criterion is compared with a more classical one, based on the Swift law and the Hill 1948 yield criterion. These constitutive models are implemented into DD3IMP, a finite element home code specifically developed to simulate sheet metal forming processes, which generically is a 3-D elastoplastic finite element code with an updated Lagrangian formulation, following a fully implicit time integration scheme, large elastoplastic strains and rotations. Solid finite elements and parametric surfaces are used to model the blank sheet and tool surfaces, respectively. Some details of the numerical implementation of the constitutive models are given. Finally, the theory is illustrated with the numerical simulation of the deep drawing of a cylindrical cup. The results show that the proposed advanced constitutive model predicts with more exactness the final shape (medium height and ears profile) of the formed part, as one can conclude from the comparison with the experimental results

  4. Rational for the use of children's motor activity as a criterion for the effectiveness of rehabilitation and recreation

    Directory of Open Access Journals (Sweden)

    A.G. Platonova

    2013-11-01

    Full Text Available Purpose – justified the use of physical activity for children as a criterion for recreation. Studied the relationship of this index with morphological and functional features of development and the level of hygiene knowledge. The study involved 54 pupils aged 10-14 years. Results: It is shown that the level of physical activity (1282,37 ± 289,20 locomotion per day. The value of basal metabolism reaches (1350,51 ± 33,69 kcal. Established direct correlation with the main motor activity exchange (r = 0,81; body weight (r = 0,80; circumference of the chest in the pause / inspiratory / expiratory (r = 0,70-0,71; vital capacity (r = 0,37; hand muscular strength (r = 0,51-0,58. The estimation of the physical development of children by Quetelet index: mass deficit is set at 12.96%, 29.63% obese, normal physical development at 51.85% overweight at 5.56%. Conclusions: The recommended value of physical activity as a criterion for recreation and health of school children. Its definition reflects the functional state of the school, as one of the criteria for defining the health, predicts its changes, which is especially valuable in monitoring.

  5. A Deeper Understanding of Stability in the Solar Wind: Applying Nyquist's Instability Criterion to Wind Faraday Cup Data

    Science.gov (United States)

    Alterman, B. L.; Klein, K. G.; Verscharen, D.; Stevens, M. L.; Kasper, J. C.

    2017-12-01

    Long duration, in situ data sets enable large-scale statistical analysis of free-energy-driven instabilities in the solar wind. The plasma beta and temperature anisotropy plane provides a well-defined parameter space in which a single-fluid plasma's stability can be represented. Because this reduced parameter space can only represent instability thresholds due to the free energy of one ion species - typically the bulk protons - the true impact of instabilities on the solar wind is under estimated. Nyquist's instability criterion allows us to systematically account for other sources of free energy including beams, drifts, and additional temperature anisotropies. Utilizing over 20 years of Wind Faraday cup and magnetic field observations, we have resolved the bulk parameters for three ion populations: the bulk protons, beam protons, and alpha particles. Applying Nyquist's criterion, we calculate the number of linearly growing modes supported by each spectrum and provide a more nuanced consideration of solar wind stability. Using collisional age measurements, we predict the stability of the solar wind close to the sun. Accounting for the free-energy from the three most common ion populations in the solar wind, our approach provides a more complete characterization of solar wind stability.

  6. A criterion for testing hypotheses about the covariance function of a stationary Gaussian stochastic process

    OpenAIRE

    Kozachenko, Yuriy; Troshki, Viktor

    2015-01-01

    We consider a measurable stationary Gaussian stochastic process. A criterion for testing hypotheses about the covariance function of such a process using estimates for its norm in the space $L_p(\\mathbb {T}),\\,p\\geq1$, is constructed.

  7. A criterion of orthogonality on the assumption and restrictions in subgrid-scale modelling of turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Fang, L. [LMP, Ecole Centrale de Pékin, Beihang University, Beijing 100191 (China); Co-Innovation Center for Advanced Aero-Engine, Beihang University, Beijing 100191 (China); Sun, X.Y. [LMP, Ecole Centrale de Pékin, Beihang University, Beijing 100191 (China); Liu, Y.W., E-mail: liuyangwei@126.com [National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics, School of Energy and Power Engineering, Beihang University, Beijing 100191 (China); Co-Innovation Center for Advanced Aero-Engine, Beihang University, Beijing 100191 (China)

    2016-12-09

    In order to shed light on understanding the subgrid-scale (SGS) modelling methodology, we analyze and define the concepts of assumption and restriction in the modelling procedure, then show by a generalized derivation that if there are multiple stationary restrictions in a modelling, the corresponding assumption function must satisfy a criterion of orthogonality. Numerical tests using one-dimensional nonlinear advection equation are performed to validate this criterion. This study is expected to inspire future research on generally guiding the SGS modelling methodology. - Highlights: • The concepts of assumption and restriction in the SGS modelling procedure are defined. • A criterion of orthogonality on the assumption and restrictions is derived. • Numerical tests using one-dimensional nonlinear advection equation are performed to validate this criterion.

  8. Entanglement criterion for tripartite systems based on local sum uncertainty relations

    Science.gov (United States)

    Akbari-Kourbolagh, Y.; Azhdargalam, M.

    2018-04-01

    We propose a sufficient criterion for the entanglement of tripartite systems based on local sum uncertainty relations for arbitrarily chosen observables of subsystems. This criterion generalizes the tighter criterion for bipartite systems introduced by Zhang et al. [C.-J. Zhang, H. Nha, Y.-S. Zhang, and G.-C. Guo, Phys. Rev. A 81, 012324 (2010), 10.1103/PhysRevA.81.012324] and can be used for both discrete- and continuous-variable systems. It enables us to detect the entanglement of quantum states without having a complete knowledge of them. Its utility is illustrated by some examples of three-qubit, qutrit-qutrit-qubit, and three-mode Gaussian states. It is found that, in comparison with other criteria, this criterion is able to detect some three-qubit bound entangled states more efficiently.

  9. Focused information criterion and model averaging based on weighted composite quantile regression

    KAUST Repository

    Xu, Ganggang; Wang, Suojin; Huang, Jianhua Z.

    2013-01-01

    We study the focused information criterion and frequentist model averaging and their application to post-model-selection inference for weighted composite quantile regression (WCQR) in the context of the additive partial linear models. With the non

  10. Relations Between Stressors and Job Performance: An Aggregate-Level Investigation Using Multiple Criterion Measures

    National Research Council Canada - National Science Library

    Thomas, Jeffrey

    2002-01-01

    .... Army Combat Brigades. Unlike previous studies that have focused exclusively on in-role performance, we examined relations between stressors and multiple performance criterion measures, which corresponded to in-role...

  11. TEMPERATURE-DEFORMATION CRITERION OF OPTIMIZATION OF FINE DRAWING HIGH CARBON WIRE ROUTE

    Directory of Open Access Journals (Sweden)

    Y. L. Bobarikin

    2012-01-01

    Full Text Available The temperature-deformation criterion of assessment and optimization of routes of the thin high-carbon wire drawing enabling to increase plastic properties of wire at retaining of its durability is offered.

  12. Criterion for the onset of quench for low-flow reflood

    International Nuclear Information System (INIS)

    Hsu, Y.Y.; Young, M.W.

    1982-07-01

    This study provides a criterion for the onset of quench for low flow reflood. The criterion is a combination of two conditions: T/sub clad/ < T/sub limiting quench/ where T = Temperature, and α < 0.95 where α = void fraction. This criterion was obtained by examining temperature data from tests simulating PWR reflood, such as FLECHT, THTF, PBF, CCTF, and FEBA tests, with void fraction data from CCTF, FEBA, and FLECHT low flood tests. The data show that quenching initiated at α = 0.95 and that the majority of quench occurred at void fractions near 0.85. The results show that rods can be completely quenched by entrained droplets even if the collapsed liquid level does not advance. A thorough discussion of the analysis which supports this quench criterion is given in the text of this report

  13. Assessing stress-related treatment needs among girls at risk for poor functional outcomes: The impact of cumulative adversity, criterion traumas, and non-criterion events.

    Science.gov (United States)

    Lansing, Amy E; Plante, Wendy Y; Beck, Audrey N

    2017-05-01

    Despite growing recognition that cumulative adversity (total stressor exposure, including complex trauma), increases the risk for psychopathology and impacts development, assessment strategies lag behind: Adversity-related mental health needs (symptoms, functional impairment, maladaptive coping) are typically assessed in response to only one qualifying Criterion-A traumatic event. This is especially problematic for youth at-risk for health and academic disparities who experience cumulative adversity, including non-qualifying events (separation from caregivers) which may produce more impairing symptomatology. Data from 118 delinquent girls demonstrate: (1) an average of 14 adverse Criterion-A and non-Criterion event exposures; (2) serious maladaptive coping strategies (self-injury) directly in response to cumulative adversity; (3) more cumulative adversity-related than worst-event related symptomatology and functional impairment; and (4) comparable symptomatology, but greater functional impairment, in response to non-Criterion events. These data support the evaluation of mental health needs in response to cumulative adversity for optimal identification and tailoring of services in high-risk populations to reduce disparities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Between engagement and information

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Brynskov, Martin

    2009-01-01

    This paper discusses the initial findings from a dual case study, describing two interactive urban installations and reflecting on their design and use. The two installations are Climate on the Wall, an interactive media facade, and CO2nfession/CO2mmitment, a video installation with user-generated...... content. Both were designed to contribute to the effort of making people in the city aware of the municipal goal of becoming CO2 neutral by the year 2030. They were designed as part of a larger exhibition to engage individual citizens in a concrete way towards the somewhat more abstract end: CO2...

  15. Engaging the Shopping Experience

    DEFF Research Database (Denmark)

    Sørensen, Sanne Dollerup

    The revenues in brick-and-mortar stores have declined in the last decade, not least due to competition from online shopping. This thesis investigates how traditional stores might use principles from experience design to reverse this tendency. Brick-and-mortar stores are very important...... the interest in brick-and-mortar stores by engaging the customers emotionally. This thesis suggests that using insights from Possible World Theory in designing stores is one way to do this. Theoretically the thesis is interdisciplinary by drawing on knowledge from a wide spectrum of fields such as consumer...

  16. A second perspective on the Amann–Schmiedl–Seifert criterion for non-equilibrium in a three-state system

    International Nuclear Information System (INIS)

    Jia, Chen; Chen, Yong

    2015-01-01

    In the work of Amann, Schmiedl and Seifert (2010 J. Chem. Phys. 132 041102), the authors derived a sufficient criterion to identify a non-equilibrium steady state (NESS) in a three-state Markov system based on the coarse-grained information of two-state trajectories. In this paper, we present a mathematical derivation and provide a probabilistic interpretation of the Amann–Schmiedl–Seifert (ASS) criterion. Moreover, the ASS criterion is compared with some other criterions for a NESS. (paper)

  17. A Criterion for Stability of Synchronization and Application to Coupled Chua's Systems

    International Nuclear Information System (INIS)

    Wang Haixia; Lu Qishao; Wang Qingyun

    2009-01-01

    We investigate synchronization in an array network of nearest-neighbor coupled chaotic oscillators. By using of the Lyapunov stability theory and matrix theory, a criterion for stability of complete synchronization is deduced. Meanwhile, an estimate of the critical coupling strength is obtained to ensure achieving chaos synchronization. As an example application, a model of coupled Chua's circuits with linearly bidirectional coupling is studied to verify the validity of the criterion. (general)

  18. On global stability criterion for neural networks with discrete and distributed delays

    International Nuclear Information System (INIS)

    Park, Ju H.

    2006-01-01

    Based on the Lyapunov functional stability analysis for differential equations and the linear matrix inequality (LMI) optimization approach, a new delay-dependent criterion for neural networks with discrete and distributed delays is derived to guarantee global asymptotic stability. The criterion is expressed in terms of LMIs, which can be solved easily by various convex optimization algorithms. Some numerical examples are given to show the effectiveness of proposed method

  19. Relative criterion for validity of a semiclassical approach to the dynamics near quantum critical points.

    Science.gov (United States)

    Wang, Qian; Qin, Pinquan; Wang, Wen-ge

    2015-10-01

    Based on an analysis of Feynman's path integral formulation of the propagator, a relative criterion is proposed for validity of a semiclassical approach to the dynamics near critical points in a class of systems undergoing quantum phase transitions. It is given by an effective Planck constant, in the relative sense that a smaller effective Planck constant implies better performance of the semiclassical approach. Numerical tests of this relative criterion are given in the XY model and in the Dicke model.

  20. A novel delay-dependent criterion for delayed neural networks of neutral type

    International Nuclear Information System (INIS)

    Lee, S.M.; Kwon, O.M.; Park, Ju H.

    2010-01-01

    This Letter considers a robust stability analysis method for delayed neural networks of neutral type. By constructing a new Lyapunov functional, a novel delay-dependent criterion for the stability is derived in terms of LMIs (linear matrix inequalities). A less conservative stability criterion is derived by using nonlinear properties of the activation function of the neural networks. Two numerical examples are illustrated to show the effectiveness of the proposed method.

  1. A characterization of optimal portfolios under the tail mean-variance criterion

    OpenAIRE

    Owadally, I.; Landsman, Z.

    2013-01-01

    The tail mean–variance model was recently introduced for use in risk management and portfolio choice; it involves a criterion that focuses on the risk of rare but large losses, which is particularly important when losses have heavy-tailed distributions. If returns or losses follow a multivariate elliptical distribution, the use of risk measures that satisfy certain well-known properties is equivalent to risk management in the classical mean–variance framework. The tail mean–variance criterion...

  2. AUTOMATIC RECOGNITION OF FALLS IN GAIT-SLIP: A HARNESS LOAD CELL BASED CRITERION

    OpenAIRE

    Yang, Feng; Pai, Yi-Chung

    2011-01-01

    Over-head-harness systems, equipped with load cell sensors, are essential to the participants’ safety and to the outcome assessment in perturbation training. The purpose of this study was to first develop an automatic outcome recognition criterion among young adults for gait-slip training and then verify such criterion among older adults. Each of 39 young and 71 older subjects, all protected by safety harness, experienced 8 unannounced, repeated slips, while walking on a 7-m walkway. Each tri...

  3. Calculation of the residual bearing capacity of reinforced concrete beams by the rigidity (deflection) criterion

    OpenAIRE

    V.S. Utkin; S.A. Solovyov

    2015-01-01

    The article proposes the method of calculating the bearing capacity of reinforced concrete beams at the operational stage by the rigidity (deflection) criterion. The methods, which were used in the article, are integral test and probabilistic methods for describing random variables. The author offers a new technique of calculating a deflection limit by a criterion of residual deformations. The article exemplifies the usage of the evidence theory for statistical information processing in the f...

  4. Students individual engagement in GIS

    DEFF Research Database (Denmark)

    Madsen, Lene Møller; Christiansen, Frederik V; Rump, Camilla Østerberg

    2014-01-01

    This paper develops two sets of concepts to theorize why students engage differently in Geographical Information Systems (GIS). These theoretical concepts are used as an analytical lens to explore empirical data on the experiences and engagement of students enrolled in an undergraduate GIS course...... in planning and management. The analysis shows that both the theoretical perspectives and the custom and didactical contract are important to understand students' engagement in GIS. However, it is the personal desiderata that are the key to understanding the students' different engagement. Further, a temporal...... dimension and contextual awareness are important in understanding students' engagement in a broader perspective....

  5. Relationships between the coach-created motivational climate and athlete engagement in youth sport.

    Science.gov (United States)

    Curran, Thomas; Hill, Andrew P; Hall, Howard K; Jowett, Gareth E

    2015-04-01

    Youth sport is a source of well-being for adolescents, yet experiences vary and attrition can be high. We sought to better understand the coach behaviors that foster positive experiences in youth sport by examining relationships between the motivational climate and athlete engagement (viz., confidence, dedication, enthusiasm, and vigor). We reasoned that a mastery climate (emphasis on effort and learning) would correspond with higher engagement, whereas a performance climate (emphasis on ability and outcome) was expected to correspond with lower engagement. Two-hundred sixty adolescent soccer players completed measures of engagement and perceived coach motivational climate. All dimensions of engagement were positively predicted by a mastery climate. Furthermore, cognitive aspects of engagement were positively predicted by a performance climate. Canonical correlation analysis indicated that a composite of engagement was positively associated with a mastery climate. Results suggest that a mastery climate offers a means of promoting higher levels of overall engagement.

  6. Multiaxial fatigue criterion based on parameters from torsion and axial S-N curve

    Directory of Open Access Journals (Sweden)

    M. Margetin

    2016-07-01

    Full Text Available Multiaxial high cycle fatigue is a topic that concerns nearly all industrial domains. In recent years, a great deal of recommendations how to address problems with multiaxial fatigue life time estimation have been made and a huge progress in the field has been achieved. Until now, however, no universal criterion for multiaxial fatigue has been proposed. Addressing this situation, this paper offers a design of a new multiaxial criterion for high cycle fatigue. This criterion is based on critical plane search. Damage parameter consists of a combination of normal and shear stresses on a critical plane (which is a plane with maximal shear stress amplitude. Material parameters used in proposed criterion are obtained from torsion and axial S-N curves. Proposed criterion correctly calculates life time for boundary loading condition (pure torsion and pure axial loading. Application of proposed model is demonstrated on biaxial loading and the results are verified with testing program using specimens made from S355 steel. Fatigue material parameters for proposed criterion and multiple sets of data for different combination of axial and torsional loading have been obtained during the experiment.

  7. A new criterion of photostimulated luminescence (PSL) method to detect irradiated traditional Chinese medicinal herbs

    International Nuclear Information System (INIS)

    Zhang, Liwen; Lin, Tong; Jiang, Yingqiao; Bi, Fujun

    2013-01-01

    This work used a new criterion to analyze 162 varieties (222 batches) of traditional Chinese medicinal herbs based on the European Standard EN 13751 (2009. Foodstuffs—Detection of Irradiated Food Using Photostimulated Luminescence. European Committee for Standardization, Brussels, Belgium). The characteristics of PSL signals are described, and a new criterion is established. Compared to EN 13751, the new criterion uses clearer definition to evaluate instead of the ambiguous descriptions in EN Standard, such as “much greater than” and “within the same order of magnitude”. Moreover, the accuracy of the new criterion is as good as or better than EN Standard in regard to classifying irradiated and non-irradiated traditional Chinese medicinal herbs. It can help to avoid false positive result when a non-irradiated herb got a screening PSL measurement above 5000 counts/60 s. This new criterion of photostimulated luminescence method can be applied to identify the irradiation status of traditional Chinese medicinal herbs, even if the medicinal herbs were irradiated at a low dose (0.3 kGy) or stored in the dark at room temperature for 24 months after the irradiation treatment. - Highlights: • Clearer evaluation criterion instead of the ambiguous descriptions in EN 13751. • Accuracy satisfied. • Large sample size provides outstanding representativeness. • Systematical evaluation on PSL method

  8. A new repair criterion for steam generator tubes with axial cracks based on probabilistic integrity assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun-Su; Oh, Chang-Kyun [KEPCO Engineering and Construction Company, Inc., 269, Hyeoksin-ro, Gimcheon, Gyeongsangbuk-do 39660 (Korea, Republic of); Chang, Yoon-Suk, E-mail: yschang@khu.ac.kr [Department of Nuclear Engineering, College of Engineering, Kyung Hee University, 1732 Deokyoungdaero, Giheung, Yongin, Gyeonggi 446-701 (Korea, Republic of)

    2017-03-15

    Highlights: • Probabilistic assessment was performed for axially cracked steam generator tubes. • The threshold crack sizes were determined based on burst pressures of the tubes. • A new repair criterion was suggested as a function of operation time. - Abstract: Steam generator is one of the major components in a nuclear power plant, and it consists of thousands of thin-walled tubes. The operating record of the steam generators has indicated that a number of axial cracks due to stress corrosion have been frequently detected in the tubes. Since the tubes are closely related to the safety and also the efficiency of a nuclear power plant, an establishment of the appropriate repair criterion for the defected tubes and its applications are necessary. The objective of this paper is to develop an accurate repair criterion for the tubes with axial cracks. To do this, a thorough review is performed on the key parameters affecting the tube integrity, and then the probabilistic integrity assessment is carried out by considering the various uncertainties. In addition, the sizes of critical crack are determined by comparing the burst pressure of the cracked tube with the required performance criterion. Based on this result, the new repair criterion for the axially cracked tubes is defined from the reasonably conservative value such that the required performance criterion in terms of the burst pressure is able to be met during the next operating period.

  9. Relationship quality and student engagement

    Science.gov (United States)

    Culver, Jennifer

    The purpose of this study was to examine the qualities of support, relatedness, and negative interaction within parent-child and teacher-student relationships and their association with cognitive, psychological, and behavioral engagement. Additionally, this study explored the contributions of cognitive and psychological engagement on behavioral engagement. The role of gender, grade, and ethnicity on relationship quality and engagement was also considered. Participants (n=311) were students in grades three through five from a suburban school district in southeastern Michigan. Perceptions of teacher-student relationship quality varied by grade level. In general, younger students reported greater teacher support and relatedness in comparison to older students. Conversely, older students perceived greater conflict within the teacher-student relationship. Student engagement also varied by grade level, with younger students reporting greater engagement than older students. Ethnicity also contributed to variance in student engagement, with African American students reporting significantly more engagement than Caucasian or Multiracial students. Teacher-student relationship quality was a significant predictor of student engagement, even after controlling for student characteristics and parent-child relationship variables. Results of path analysis revealed that cognitive and psychological engagement contributed significantly to behavioral engagement.

  10. Civic Engagement Scale

    Directory of Open Access Journals (Sweden)

    Amy Doolittle

    2013-07-01

    Full Text Available This study reports on the development and validation of the Civic Engagement Scale (CES. This scale is developed to be easily administered and useful to educators who are seeking to measure the attitudes and behaviors that have been affected by a service-learning experience. This instrument was administered as a validation study in a purposive sample of social work and education majors at three universities (N = 513 with a return of 354 (69%. After the reliability and validity analysis was completed, the Attitude subscale was left with eight items and a Cronbach’s alpha level of .91. The Behavior subscale was left with six items and a Cronbach’s alpha level of .85. Principal component analysis indicated a two-dimensional scale with high loadings on both factors (mean factor loading for the attitude factor = .79, and mean factor loading for the behavior factor = .77. These results indicate that the CES is strong enough to recommend its use in educational settings. Preliminary use has demonstrated that this scale will be useful to researchers seeking to better understand the relationship of attitudes and behaviors with civic engagement in the service-learning setting. The primary limitations of this research are that the sample was limited to social work and education majors who were primarily White (n = 312, 88.1% and female (n = 294, 83.1%. Therefore, further research would be needed to generalize this research to other populations.

  11. A Variance Minimization Criterion to Feature Selection Using Laplacian Regularization.

    Science.gov (United States)

    He, Xiaofei; Ji, Ming; Zhang, Chiyuan; Bao, Hujun

    2011-10-01

    In many information processing tasks, one is often confronted with very high-dimensional data. Feature selection techniques are designed to find the meaningful feature subset of the original features which can facilitate clustering, classification, and retrieval. In this paper, we consider the feature selection problem in unsupervised learning scenarios, which is particularly difficult due to the absence of class labels that would guide the search for relevant information. Based on Laplacian regularized least squares, which finds a smooth function on the data manifold and minimizes the empirical loss, we propose two novel feature selection algorithms which aim to minimize the expected prediction error of the regularized regression model. Specifically, we select those features such that the size of the parameter covariance matrix of the regularized regression model is minimized. Motivated from experimental design, we use trace and determinant operators to measure the size of the covariance matrix. Efficient computational schemes are also introduced to solve the corresponding optimization problems. Extensive experimental results over various real-life data sets have demonstrated the superiority of the proposed algorithms.

  12. PUBLICATION ACTIVITY AND ITS ROLE IN ASSESSMENT OF PROFESSIONAL ENGAGEMENT OF HEI ACADEMIC STAFF (RUSSIAN PRACTICES

    Directory of Open Access Journals (Sweden)

    I. B. Ardashkin

    2016-01-01

    Full Text Available The aim of the research is to analyze and summarize the Russian best practices of using the publication activity as a criterion to assess the professional activity of the academic staff; to identify the role of motivational factors as a method to manage and control the publication activity of the academic staff.Methods. The authors address the methodology of comprehensive research based on the method of document analysis, comparative analysis, and method of secondary use of sociological and psychological data.Results and scientific novelty concludes in presenting Russian and international best practices generalized on using the publication activity to assess the engagement of HEI (Higher Educational Institution academic staff; the most appropriate formats of using the publication activity as a criterion to assess the research component of the academic staff engagement are defined. Degree of reliability of this criterion is shown – its strengths and shortcomings. The conclusion is drawn on need of the essential changes in management of publication activity affecting both professional and motivational spheres of scientific and pedagogical staff. The most acceptable options of measurement of staff work efficiency of this category are formulated.Practical significance. The research outcomes can be the corpus for designing the assessment method for the professional engagement of the academic staff.

  13. Three-Dimensional Dynamic Rupture in Brittle Solids and the Volumetric Strain Criterion

    Science.gov (United States)

    Uenishi, K.; Yamachi, H.

    2017-12-01

    As pointed out by Uenishi (2016 AGU Fall Meeting), source dynamics of ordinary earthquakes is often studied in the framework of 3D rupture in brittle solids but our knowledge of mechanics of actual 3D rupture is limited. Typically, criteria derived from 1D frictional observations of sliding materials or post-failure behavior of solids are applied in seismic simulations, and although mode-I cracks are frequently encountered in earthquake-induced ground failures, rupture in tension is in most cases ignored. Even when it is included in analyses, the classical maximum principal tensile stress rupture criterion is repeatedly used. Our recent basic experiments of dynamic rupture of spherical or cylindrical monolithic brittle solids by applying high-voltage electric discharge impulses or impact loads have indicated generation of surprisingly simple and often flat rupture surfaces in 3D specimens even without the initial existence of planes of weakness. However, at the same time, the snapshots taken by a high-speed digital video camera have shown rather complicated histories of rupture development in these 3D solid materials, which seem to be difficult to be explained by, for example, the maximum principal stress criterion. Instead, a (tensile) volumetric strain criterion where the volumetric strain (dilatation or the first invariant of the strain tensor) is a decisive parameter for rupture seems more effective in computationally reproducing the multi-directionally propagating waves and rupture. In this study, we try to show the connection between this volumetric strain criterion and other classical rupture criteria or physical parameters employed in continuum mechanics, and indicate that the criterion has, to some degree, physical meanings. First, we mathematically illustrate that the criterion is equivalent to a criterion based on the mean normal stress, a crucial parameter in plasticity. Then, we mention the relation between the volumetric strain criterion and the

  14. Burnout and Engagement: Relative Importance of Predictors and Outcomes in Two Health Care Worker Samples.

    Science.gov (United States)

    Fragoso, Zachary L; Holcombe, Kyla J; McCluney, Courtney L; Fisher, Gwenith G; McGonagle, Alyssa K; Friebe, Susan J

    2016-06-09

    This study's purpose was twofold: first, to examine the relative importance of job demands and resources as predictors of burnout and engagement, and second, the relative importance of engagement and burnout related to health, depressive symptoms, work ability, organizational commitment, and turnover intentions in two samples of health care workers. Nurse leaders (n = 162) and licensed emergency medical technicians (EMTs; n = 102) completed surveys. In both samples, job demands predicted burnout more strongly than job resources, and job resources predicted engagement more strongly than job demands. Engagement held more weight than burnout for predicting commitment, and burnout held more weight for predicting health outcomes, depressive symptoms, and work ability. Results have implications for the design, evaluation, and effectiveness of workplace interventions to reduce burnout and improve engagement among health care workers. Actionable recommendations for increasing engagement and decreasing burnout in health care organizations are provided. © 2016 The Author(s).

  15. Criterion validity of a Wechsler-III scale short form in a sample of Brazilian Elderly

    Directory of Open Access Journals (Sweden)

    Eliane Ferreira Carvalho Banhato

    Full Text Available Abstract Although a normative process, changes in cognitive functioning vary among older adults. The differential diagnosis between normal and pathological aging must be made early using psychometrically adequate measures. Objectives: To assess the evidence of criterion validity of a Short Form (SF of the Wechsler-III Scale containing eight subtests (SF8 by determining its sensitivity, specificity, positive and negative predictive values and cut-off points for Brazilian elderly from different age groups. Methods: 168 individuals, aged 60 years or above, living in the community or in an institution, were assigned to case and control groups, and investigated according to age range. Measures included a sociodemographic questionnaire, the Mini-Mental State Examination (MMSE, Verbal Fluency Test, Clock-Drawing Test and the SF8. Results: More than two thirds of the sample was women (73.8%, mean age was 74.5 years (SD=8.9, mean education was 6.2 years (SD=4.8 and 40.5% were widows/widowers. In the total sample, the best cut-off point for the SF8 was 142 while cut offs among individuals aged 60 to 69 years, 70 to 79 years, and more than 80 years were 160, 129 and 129, respectively. Conclusions: The results demonstrated the importance of different cut-off points for different age ranges. Sensitivity and specificity values of the SF8 were sufficiently high to warrant the use of the SF8 as an instrument to identify cognitive impairment in the elderly.

  16. Fatigue crack growth threshold as a design criterion - statistical scatter and load ratio in the Kitagawa-Takahashi diagram

    International Nuclear Information System (INIS)

    Kolitsch, S.; Gänser, H.-P.; Maierhofer, J.; Pippan, R.

    2016-01-01

    Cracks in components reduce the endurable stress so that the endurance limit obtained from common smooth fatigue specimens cannot be used anymore as a design criterion. In such cases, the Kitagawa-Takahashi diagram can be used to predict the admissible stress range for infinite life, at a given crack length and stress range. This diagram is constructed for a single load ratio R. However, in typical mechanical engineering applications, the load ratio R varies widely due to the applied load spectra and residual stresses. In the present work an extended Kitagawa-Takahashi diagram accounting for crack length, crack extension and load ratio is constructed. To describe the threshold behaviour of short cracks, a master resistance curve valid for a wide range of steels is developed using a statistical approach. (paper)

  17. Engaged to Learn Ways of Engaging ESL Learners

    Directory of Open Access Journals (Sweden)

    Brian Tomlinson

    2010-01-01

    Full Text Available In this paper I am going to argue that our most important role as language teachers is to provide potentially engaging materials for our learners and then to make use of them in optimally engaging ways. If we do not engage our learners most of the time no amount of exposure, teaching, practice or use of the language will help them to achieve sufficient language acquisition and development.

  18. Collaborative engagement experiment

    Science.gov (United States)

    Mullens, Katherine; Troyer, Bradley; Wade, Robert; Skibba, Brian; Dunn, Michael

    2006-05-01

    Unmanned ground and air systems operating in collaboration have the potential to provide future Joint Forces a significant capability for operations in complex terrain. Collaborative Engagement Experiment (CEE) is a consolidation of separate Air Force, Army and Navy collaborative efforts within the Joint Robotics Program (JRP) to provide a picture of the future of unmanned warfare. The Air Force Research Laboratory (AFRL), Material and Manufacturing Directorate, Aerospace Expeditionary Force Division, Force Protection Branch (AFRL/MLQF), The Army Aviation and Missile Research, Development and Engineering Center (AMRDEC) Joint Technology Center (JTC)/Systems Integration Laboratory (SIL), and the Space and Naval Warfare Systems Center - San Diego (SSC San Diego) are conducting technical research and proof of principle experiments for an envisioned operational concept for extended range, three dimensional, collaborative operations between unmanned systems, with enhanced situational awareness for lethal operations in complex terrain. This paper describes the work by these organizations to date and outlines some of the plans for future work.

  19. Decoupling, re-engaging

    DEFF Research Database (Denmark)

    Rose, Jeremy; Schlichter, Bjarne Rerup

    2013-01-01

    the life of a major project and the complex demands of managing those fluctuations. We investigate evolving trust relationships in a longitudinal case analysis of a large integrated hospital system implementation for the Faroe Islands. Trust relationships suffered various breakdowns, but the project...... was able to recover and eventually meet its goals. Based on concepts from Giddens’ later work on modernity, we develop two approaches for managing dynamic trust relationships in implementation projects: decoupling and re-engaging....... in the project is contingent upon many factors, is likely to vary over time and should not be taken for granted. Previous studies have identified the relationship between trust and project outcomes and suggested trust-building strategies but have largely ignored the dynamic quality of trust relations through...

  20. Engaging in Affective Practices

    DEFF Research Database (Denmark)

    Galløe, Lotte Rannveig

    schools, the paper develops an affective-power approach drawing on Foucault’s notion of power and Whetherell’s conceptualisation of affect. The approach captures the affective dimension of governing and resistance in interactional practice that engages teachers and pupils. This enables a research focus......The paper presents how the merging of the theoretical concepts ‘Affect’ and ‘Power’ faces methodological and ethical challenges when entangled in teachers’ and pupils’ practice. Based on a study of pedagogical methods aiming to shape certain affective relations and avoid conflicts in Danish primary....... Witnessing tense conflict situations taking place I as a researcher get affected as well, and in turn affect the practice myself. Because, both the teacher, pupil, and I are well aware of my research focus on power and affect, being observed in conflictual situations contributes to pervasive shame...

  1. Engaging with mobile methods

    DEFF Research Database (Denmark)

    Jensen, Martin Trandberg

    2014-01-01

    This chapter showcases how mobile methods are more than calibrated techniques awaiting application by tourism researchers, but productive in the enactment of the mobile (Law and Urry, 2004). Drawing upon recent findings deriving from a PhD course on mobility and mobile methods it reveals...... the conceptual ambiguousness of the term ‘mobile methods’. In order to explore this ambiguousness the chapter provides a number of examples deriving from tourism research, to explore how mobile methods are always entangled in ideologies, predispositions, conventions and practice-realities. Accordingly......, the engagements with methods are acknowledged to be always political and contextual, reminding us to avoid essentialist discussions regarding research methods. Finally, the chapter draws on recent fieldwork to extend developments in mobilities-oriented tourism research, by employing auto-ethnography to call...

  2. Between engagement and information

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Brynskov, Martin

    2009-01-01

    This paper discusses the initial findings from a dual case study, describing two interactive urban installations and reflecting on their design and use. The two installations are Climate on the Wall, an interactive media facade, and CO2nfession/CO2mmitment, a video installation with user......-generated content. Both were designed to contribute to the effort of making people in the city aware of the municipal goal of becoming CO2 neutral by the year 2030. They were designed as part of a larger exhibition to engage individual citizens in a concrete way towards the somewhat more abstract end: CO2...... neutrality. In the paper we present the background for the work, describe the installations, report on initial findings regarding their use and reception, and, finally, outline what research agendas we plan to pursue in upcoming work....

  3. Criterion learning in rule-based categorization: simulation of neural mechanism and new data.

    Science.gov (United States)

    Helie, Sebastien; Ell, Shawn W; Filoteo, J Vincent; Maddox, W Todd

    2015-04-01

    In perceptual categorization, rule selection consists of selecting one or several stimulus-dimensions to be used to categorize the stimuli (e.g., categorize lines according to their length). Once a rule has been selected, criterion learning consists of defining how stimuli will be grouped using the selected dimension(s) (e.g., if the selected rule is line length, define 'long' and 'short'). Very little is known about the neuroscience of criterion learning, and most existing computational models do not provide a biological mechanism for this process. In this article, we introduce a new model of rule learning called Heterosynaptic Inhibitory Criterion Learning (HICL). HICL includes a biologically-based explanation of criterion learning, and we use new category-learning data to test key aspects of the model. In HICL, rule selective cells in prefrontal cortex modulate stimulus-response associations using pre-synaptic inhibition. Criterion learning is implemented by a new type of heterosynaptic error-driven Hebbian learning at inhibitory synapses that uses feedback to drive cell activation above/below thresholds representing ionic gating mechanisms. The model is used to account for new human categorization data from two experiments showing that: (1) changing rule criterion on a given dimension is easier if irrelevant dimensions are also changing (Experiment 1), and (2) showing that changing the relevant rule dimension and learning a new criterion is more difficult, but also facilitated by a change in the irrelevant dimension (Experiment 2). We conclude with a discussion of some of HICL's implications for future research on rule learning. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Zero mass field quantization and Kibble's long-range force criterion for the Goldstone theorem

    International Nuclear Information System (INIS)

    Wright, S.H.

    1981-01-01

    The central theme of the dissertation is an investigation of the long-range force criterion used by Kibble in his discussion of the Goldstone Theorem. This investigation is broken up into the following sections: I. Introduction. Spontaneous symmetry breaking, the Goldstone Theorem and the conditions under which it holds are discussed. II. Massless Wave Expansions. In order to make explicit calculations of the operator commutators used in applying Kibble's criterion, it is necessary to work out the operator expansions for a massless field. Unusual results are obtained which include operators corresponding to classical macroscopic field modes. III. The Kibble Criterion for Simple Models Exhibiting Spontaneously Broken Symmetries. The results of the previous section are applied to simple models with spontaneously broken symmetries, namely, the real scalar massless field and the Goldstone model without gauge coupling. IV. The Higgs Mechanism in Classical Field Theory. It is shown that the Higgs Mechanism has a simple interpretation in terms of classical field theory, namely, that it arises from a derivative coupling term between the Goldstone fields and the gauge fields. V. The Higgs Mechanism and Kibble's Criterion. This section draws together the material discussed in sections II to IV. Explicit calculations are made to evaluate Kibble's criterion on a Goldstone-Higgs type of model in the Coulomb gauge. It is found, as expected, that the criterion is not met, but not for reasons relating to the range of the mediating force. By referring to the findings of sections III and IV, it is concluded that the common denominator underlying both the Higgs Mechanism and the failure of Kibble's criterion is a structural aspect of the field equations: derivative coupling between fields

  5. Perspective-Taking Increases Willingness to Engage in Intergroup Contact

    OpenAIRE

    Wang, Cynthia S.; Kenneth, Tai; Ku, Gillian; Galinsky, Adam D.

    2014-01-01

    The current research explored whether perspective-taking increases willingness to engage in contact with stereotyped outgroup members. Across three studies, we find that perspective-taking increases willingness to engage in contact with negatively-stereotyped targets. In Study 1, perspective-takers sat closer to, whereas stereotype suppressors sat further from, a hooligan compared to control participants. In Study 2, individual differences in perspective-taking tendencies predicted individual...

  6. Engaging men in health care.

    Science.gov (United States)

    Malcher, Greg

    2009-03-01

    Engaging men in health care involves a multifaceted approach that has as its main principle the recognition that men consume health care differently to women. This article identifies barriers to engaging men in health care and offers potential and existing solutions to overcome these barriers in a range of health care settings. The concept of multiple masculinities recognises that not all men can be engaged via a particular technique or strategy. The perception that men are disinterested in their health is challenged and a range of approaches discussed, both in the community and in health care facilities. In the general practice setting opportunities exist for the engagement of men at the reception desk and waiting room, as well as during the consultation. Use of the workplace in engaging men is discussed. Future activities to build the capacity of health care providers to better engage men are identified and the role of policy and program development is addressed.

  7. Student Engagement In Inclusive Classrooms

    DEFF Research Database (Denmark)

    Rangvid, Beatrice Schindler

    There is general agreement that to thrive and learn at their best, students must be engaged. However, schools face a particular challenge to provide a suitable and engaging learning environment for SEN (special educational needs) students who are educated in general education classes. Using data......-students as for other students. This highlights the need for better inclusion initiatives aimed at strengthening engagement of SEN-students in regular classrooms....

  8. Employee Engagement: A Literature Review

    OpenAIRE

    Dharmendra MEHTA; Naveen K. MEHTA

    2013-01-01

    Motivated and engaged employees tend to contribute more in terms of organizational productivity and support in maintaining a higher commitment level leading to the higher customer satisfaction. Employees Engagement permeates across the employee-customer boundary, where revenue, corporate goodwill, brand image are also at stake. This paper makes an attempt to study the different dimensions of employee engagement with the help of review of literature. This can be used to provide an overview and...

  9. Engagement of Students Teaching Assistants

    DEFF Research Database (Denmark)

    Schlichter, Bjarne Rerup; Brandt, Charlotte J.

    2016-01-01

    This paper reports from five years experiences of engaging young student teaching assistants into the continuously development of a course by involving them in research on pedagogical as well as other themes from the course. The purpose of the paper is to pave the road for a more engaged and inte......This paper reports from five years experiences of engaging young student teaching assistants into the continuously development of a course by involving them in research on pedagogical as well as other themes from the course. The purpose of the paper is to pave the road for a more engaged...... are identified accompanied with suggestions for further research....

  10. Employee Engagement: A Literature Review

    Directory of Open Access Journals (Sweden)

    Dharmendra MEHTA

    2013-12-01

    Full Text Available Motivated and engaged employees tend to contribute more in terms of organizational productivity and support in maintaining a higher commitment level leading to the higher customer satisfaction. Employees Engagement permeates across the employee-customer boundary, where revenue, corporate goodwill, brand image are also at stake. This paper makes an attempt to study the different dimensions of employee engagement with the help of review of literature. This can be used to provide an overview and references on some of the conceptual and practical work undertaken in the area of the employee engagement practices.

  11. VALIDITY OF EXCESS ENTROPY PRODUCTION CRITERION OF THERMODYNAMIC STABILITY FOR NONEQUILIBRIUM STEADY STATES

    Institute of Scientific and Technical Information of China (English)

    吴金平

    1991-01-01

    The relation between the excess entropy production criterion of thermodynamic stabilityfor nonequilibrium states and kinetic linear stability principle is discussed. It is shown thatthe condition required by the excess entropy production criterion generally is sufficient, butnot necessary to judge the system stability. The condition required by the excess entropyproduction criterion is stronger than that of the linear stability principle. Only when theproduct matrix between the linearized matrix of kinetic equations and matrix of quadraticform of second-order excess entropy is symmetric, is the condition required by the excessentropy production criterion that the steady steate is asymptotically stable (δ_xP>0) necessaryand sufficient. The counterexample given by Fox to prove that the excess entropy, (δ~2S)ss,is not a Liapunov function is incorrect. Contradictory to his conclusion, the counterexampleis just a positive one that proves that the excess entropy is a Liapunov function. Moreover,the excess entropy production criterion is not limited by symmetric conditions of the linear-ized matrix of kinetic equations. The excess entropy around nonequilibrium steady states,(δ~2S)ss, is a Liapunov function of thermodynamic system.

  12. Fulfillment of the kinetic Bohm criterion in a quasineutral particle-in-cell model

    International Nuclear Information System (INIS)

    Ahedo, Eduardo; Santos, Robert; Parra, Felix I.

    2010-01-01

    Quasineutral particle-in-cell models of ions must fulfill the kinetic Bohm criterion, in its inequality form, at the domain boundary in order to match correctly with solutions of the Debye sheaths tied to the walls. The simple, fluid form of the Bohm criterion is shown to be a bad approximation of the exact, kinetic form when the ion velocity distribution function has a significant dispersion and involves different charge numbers. The fulfillment of the Bohm criterion is measured by a weighting algorithm at the boundary, but linear weighting algorithms have difficulties to reproduce the nonlinear behavior around the sheath edge. A surface weighting algorithm with an extended temporal weighting is proposed and shown to behave better than the standard volumetric weighting. Still, this must be supplemented by a forcing algorithm of the kinetic Bohm criterion. This postulates a small potential fall in a supplementary, thin, transition layer. The electron-wall interaction is shown to be of little relevance in the fulfillment of the Bohm criterion.

  13. PTSD's risky behavior criterion: Relation with DSM-5 PTSD symptom clusters and psychopathology.

    Science.gov (United States)

    Contractor, Ateka A; Weiss, Nicole H; Dranger, Paula; Ruggero, Camilo; Armour, Cherie

    2017-06-01

    A new symptom criterion of reckless and self-destructive behaviors (E2) was recently added to posttraumatic stress disorder's (PTSD) diagnostic criteria in DSM-5, which is unsurprising given the well-established relation between PTSD and risky behaviors. Researchers have questioned the significance and incremental validity of this symptom criterion within PTSD's symptomatology. Unprecedented to our knowledge, we aim to compare trauma-exposed groups differing on their endorsement status of the risky behavior symptom on several psychopathology constructs (PTSD, depression, distress tolerance, rumination, anger). The sample included 123 trauma-exposed participants seeking mental health treatment (M age=35.70; 68.30% female) who completed self-report questionnaires assessing PTSD symptoms, depression, rumination, distress tolerance, and anger. Results of independent samples t-tests indicated that participants who endorsed the E2 criterion at a clinically significant level reported significantly greater PTSD subscale severity; depression severity; rumination facets of repetitive thoughts, counterfactual thinking, and problem-focused thinking; and anger reactions; and significantly less absorption and regulation (distress tolerance facets) compared to participants who did not endorse the E2 criterion at a clinically significant level. Results indicate the utility of the E2 criterion in identifying trauma-exposed individual with greater posttraumatic distress, and emphasize the importance of targeting such behaviors in treatment. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

  14. An analytic expression for the sheath criterion in magnetized plasmas with multi-charged ion species

    International Nuclear Information System (INIS)

    Hatami, M. M.

    2015-01-01

    The generalized Bohm criterion in magnetized multi-component plasmas consisting of multi-charged positive and negative ion species and electrons is analytically investigated by using the hydrodynamic model. It is assumed that the electrons and negative ion density distributions are the Boltzmann distribution with different temperatures and the positive ions enter into the sheath region obliquely. Our results show that the positive and negative ion temperatures, the orientation of the applied magnetic field and the charge number of positive and negative ions strongly affect the Bohm criterion in these multi-component plasmas. To determine the validity of our derived generalized Bohm criterion, it reduced to some familiar physical condition and it is shown that monotonically reduction of the positive ion density distribution leading to the sheath formation occurs only when entrance velocity of ion into the sheath satisfies the obtained Bohm criterion. Also, as a practical application of the obtained Bohm criterion, effects of the ionic temperature and concentration as well as magnetic field on the behavior of the charged particle density distributions and so the sheath thickness of a magnetized plasma consisting of electrons and singly charged positive and negative ion species are studied numerically

  15. Optimal Conformal Polynomial Projections for Croatia According to the Airy/Jordan Criterion

    Directory of Open Access Journals (Sweden)

    Dražen Tutić

    2009-05-01

    Full Text Available The paper describes optimal conformal polynomial projections for Croatia according to the Airy/Jordan criterion. A brief introduction of history and theory of conformal mapping is followed by descriptions of conformal polynomial projections and their current application. The paper considers polynomials of degrees 1 to 10. Since there are conditions in which the 1st degree polynomial becomes the famous Mercator projection, it was not considered specifically for Croatian territory. The area of Croatia was defined as a union of national territory and the continental shelf. Area definition data were taken from the Euro Global Map 1:1 000 000 for Croatia, as well as from two maritime delimitation treaties. Such an irregular area was approximated with a regular grid consisting of 11 934 ellipsoidal trapezoids 2' large. The Airy/Jordan criterion for the optimal projection is defined as minimum of weighted mean of Airy/Jordan measure of distortion in points. The value of the Airy/Jordan criterion is calculated from all 11 934 centres of ellipsoidal trapezoids, while the weights are equal to areas of corresponding ellipsoidal trapezoids. The minimum is obtained by Nelder and Mead’s method, as implemented in the fminsearch function of the MATLAB package. Maps of Croatia representing the distribution of distortions are given for polynomial degrees 2 to 6 and 10. Increasing the polynomial degree results in better projections considering the criterion, and the 6th degree polynomial provides a good ratio of formula complexity and criterion value.

  16. Covariance-Based Measurement Selection Criterion for Gaussian-Based Algorithms

    Directory of Open Access Journals (Sweden)

    Fernando A. Auat Cheein

    2013-01-01

    Full Text Available Process modeling by means of Gaussian-based algorithms often suffers from redundant information which usually increases the estimation computational complexity without significantly improving the estimation performance. In this article, a non-arbitrary measurement selection criterion for Gaussian-based algorithms is proposed. The measurement selection criterion is based on the determination of the most significant measurement from both an estimation convergence perspective and the covariance matrix associated with the measurement. The selection criterion is independent from the nature of the measured variable. This criterion is used in conjunction with three Gaussian-based algorithms: the EIF (Extended Information Filter, the EKF (Extended Kalman Filter and the UKF (Unscented Kalman Filter. Nevertheless, the measurement selection criterion shown herein can also be applied to other Gaussian-based algorithms. Although this work is focused on environment modeling, the results shown herein can be applied to other Gaussian-based algorithm implementations. Mathematical descriptions and implementation results that validate the proposal are also included in this work.

  17. Engaging with Assessment: Increasing Student Engagement through Continuous Assessment

    Science.gov (United States)

    Holmes, Naomi

    2018-01-01

    Student engagement is intrinsically linked to two important metrics in learning: student satisfaction and the quality of the student experience. One of the ways that engagement can be influenced is through careful curriculum design. Using the knowledge that many students are "assessment-driven," a low-stakes continuous weekly summative…

  18. PERARES: Public Engagement with Research and Research Engagement with Society

    NARCIS (Netherlands)

    Steinhaus, Norbert; Mulder, Henk A.J.

    2014-01-01

    PERARES is a four-year project funded by the European Community's Seventh Framework Programme which started in 2010. The acronym stands for "Public Engagement with Research and Research Engagement with Society”. The project brings together Science Shops, Civil Society Organisations (CSOs) and

  19. Student Engagement in Assessments: What Students and Teachers Find Engaging

    Science.gov (United States)

    Bae, Soung; Kokka, Kari

    2016-01-01

    Although research has shown that student engagement is strongly related to performance on assessment tasks, especially for traditionally underserved subgroups of students, increasing student engagement has not been the goal of standardized tests of content knowledge. Recent state and federal policies, however, are changing the assessment…

  20. Optimization of Thermal Object Nonlinear Control Systems by Energy Efficiency Criterion.

    Science.gov (United States)

    Velichkin, Vladimir A.; Zavyalov, Vladimir A.

    2018-03-01

    This article presents the results of thermal object functioning control analysis (heat exchanger, dryer, heat treatment chamber, etc.). The results were used to determine a mathematical model of the generalized thermal control object. The appropriate optimality criterion was chosen to make the control more energy-efficient. The mathematical programming task was formulated based on the chosen optimality criterion, control object mathematical model and technological constraints. The “maximum energy efficiency” criterion helped avoid solving a system of nonlinear differential equations and solve the formulated problem of mathematical programming in an analytical way. It should be noted that in the case under review the search for optimal control and optimal trajectory reduces to solving an algebraic system of equations. In addition, it is shown that the optimal trajectory does not depend on the dynamic characteristics of the control object.

  1. Criterion for adoption of urgent decision on population protection measures in case of NPP accident

    International Nuclear Information System (INIS)

    Konstantinov, Yu.O.

    1985-01-01

    The main table of a criterion for making decision about population protection measures in case of NPP accident is reconsidered. In comparison with the previous data the table doesn't contain contact irradiation and food-stuff contamination with 90 Sr and 137 Cs because of their insignificance relatively to external irradiation as a result of inert radioactive gaseous and halogen release and internal irradiation by iodine radioisotopes. Defining more exactly the criterion one should pay more attention to the discussion of numerical values of internal irradiation dose of thyroid gland. The choice of hazard-levels giving the foundation for making decision concerning protection measures should be determined both by biological radiation risk and scale of hazard relative protection urgebcy the degree of accuracy of potential irradiation or contamination evaluation by possibilities of measures carried out in time, difficulties, unfavourable psychologic effect and risk for population health. The criterion should permit flexibility in decision making according to concrete conditions

  2. The precautionary principle as a rational decision criterion; Foere var-prinsippet som rasjonelt beslutningsgrunnlag

    Energy Technology Data Exchange (ETDEWEB)

    Hovi, Jon

    2001-12-01

    The paper asks if the precautionary principle may be seen as a rational decision criterion. Six main questions are discussed. 1. Does the principle basically represent a particular set of political options or is it a genuine decision criterion? 2. If it is the latter, can it be reduced to any of the existing criteria for decision making under uncertainty? 3. In what kinds of situation is the principle applicable? 4. What is the relation between the precautionary principle and other principles for environmental regulation? 5. How plausible is the principle's claim that the burden of proof should be reversed? 6. Do the proponents of environmental regulation carry no burden of proof at all? A main conclusion is that, for now at least, the principle contains too many unclear elements to satisfy the requirements of precision and consistency that should reasonably be satisfied by a rational decision criterion. (author)

  3. Conflicting views on a neutrality criterion for radioactive-waste management

    International Nuclear Information System (INIS)

    Cochran, T.B.; Bodde, D.L.

    1983-01-01

    Two essays are presented by authors who agree that risks imposed on future generations through the management of radioactive waste are acceptable if they meet a criterion of neutrality, but who disagree on the interpretation of the neutrality criterion. The first viewpoint argues that acceptable isolation of high-level radioactive waste is yet to be accomplished and that a fundamental criterion for radioactive waste disposal must include consideration of the intergenerational radiation effects. The second essay promotes balanced resource allocation, technological progress, and adequate problem-solving institutions as the solution to the problem. The debate illustrates the complexities involved in applying philosophical principles to public policy, even when the principles have been agreed upon. 23 references, 1 figure

  4. A risk-based microbiological criterion that uses the relative risk as the critical limit

    DEFF Research Database (Denmark)

    Andersen, Jens Kirk; Nørrung, Birgit; da Costa Alves Machado, Simone

    2015-01-01

    A risk-based microbiological criterion is described, that is based on the relative risk associated to the analytical result of a number of samples taken from a food lot. The acceptable limit is a specific level of risk and not a specific number of microorganisms, as in other microbiological...... criteria. The approach requires the availability of a quantitative microbiological risk assessment model to get risk estimates for food products from sampled food lots. By relating these food lot risk estimates to the mean risk estimate associated to a representative baseline data set, a relative risk...... estimate can be obtained. This relative risk estimate then can be compared with a critical value, defined by the criterion. This microbiological criterion based on a relative risk limit is particularly useful when quantitative enumeration data are available and when the prevalence of the microorganism...

  5. Spatial frequency discrimination: visual long-term memory or criterion setting?

    Science.gov (United States)

    Lages, M; Treisman, M

    1998-02-01

    A long-term sensory memory is believed to account for spatial frequency discrimination when reference and test stimuli are separated by long intervals. We test an alternative proposal: that discrimination is determined by the range of test stimuli, through their entrainment of criterion-setting processes. Experiments 1 and 2 show that the 50% point of the psychometric function is largely determined by the midpoint of the stimulus range, not by the reference stimulus. Experiment 3 shows that discrimination of spatial frequencies is similarly affected by orthogonal contextual stimuli and parallel contextual stimuli and that these effects can be explained by criterion-setting processes. These findings support the hypothesis that discrimination over long intervals is explained by the operation of criterion-setting processes rather than by long-term sensory retention of a neural representation of the stimulus.

  6. Synchronization criterion for Lur'e type complex dynamical networks with time-varying delay

    International Nuclear Information System (INIS)

    Ji, D.H.; Park, Ju H.; Yoo, W.J.; Won, S.C.; Lee, S.M.

    2010-01-01

    In this Letter, the synchronization problem for a class of complex dynamical networks in which every identical node is a Lur'e system with time-varying delay is considered. A delay-dependent synchronization criterion is derived for the synchronization of complex dynamical network that represented by Lur'e system with sector restricted nonlinearities. The derived criterion is a sufficient condition for absolute stability of error dynamics between the each nodes and the isolated node. Using a convex representation of the nonlinearity for error dynamics, the stability condition based on the discretized Lyapunov-Krasovskii functional is obtained via LMI formulation. The proposed delay-dependent synchronization criterion is less conservative than the existing ones. The effectiveness of our work is verified through numerical examples.

  7. Development of a brittle fracture acceptance criterion for the International Atomic Energy Agency (IAEA)

    International Nuclear Information System (INIS)

    Sorenson, K.B.; Salzbrenner, R.; Nickell, R.E.

    1992-01-01

    An effort has been undertaken to develop a brittle fracture acceptance criterion for structural components of nuclear material transportation casks. The need for such a criterion was twofold. First, new generation cask designs have proposed the use of ferritic steels and other materials to replace the austenitic stainless steel commonly used for structural components in transport casks. Unlike austenitic stainless steel which fails in a high-energy absorbing, ductile tearing mode, it is possible for these candidate materials to fail via brittle fracture when subjected to certain combinations of elevated loading rates and low temperatures. Second, there is no established brittle fracture criterion accepted by the regulatory community that covers a broad range of structural materials. Although the existing IAEA Safety Series number-sign 37 addressed brittle fracture, its the guidance was dated and pertained only to ferritic steels. Consultant's Services Meetings held under the auspices of the IAEA have resulted in a recommended brittle fracture criterion. The brittle fracture criterion is based on linear elastic fracture mechanics, and is the result of a consensus of experts from six participating IAEA-member countries. The brittle fracture criterion allows three approaches to determine the fracture toughness of the structural material. The three approaches present the opportunity to balance material testing requirements and the conservatism of the material's fracture toughness which must be used to demonstrate resistance to brittle fracture. This work has resulted in a revised Appendix IX to Safety Series number-sign 37 which will be released as an IAEA Technical Document within the coming year

  8. Class Anxiety in Secondary Education: Exploring Structural Relations with Perceived Control, Engagement, Disaffection, and Performance.

    Science.gov (United States)

    González, Antonio; Faílde Garrido, José María; Rodríguez Castro, Yolanda; Carrera Rodríguez, María Victoria

    2015-09-14

    The aim of this study was to assess the relationships between class-related anxiety with perceived control, teacher-reported behavioral engagement, behavioral disaffection, and academic performance. Participants were 355 compulsory secondary students (9th and 10th grades; Mean age = 15.2 years; SD = 1.8 years). Structural equation models revealed performance was predicted by perceived control, anxiety, disaffection, and engagement. Perceived control predicted anxiety, disaffection, and engagement. Anxiety predicted disaffection and engagement, and partially mediated the effects from control on disaffection (β = -.277, p anxiety and performance was mediated by engagement and disaffection (β = -.295, p Anxiety, engagement, and disaffection mediated the effects of control on performance (β = .352, p < .003; CI = .279, .440). The implications of these results are discussed in the light of current theory and educational interventions.

  9. Students Individual Engagement in GIS

    Science.gov (United States)

    Madsen, Lene Møller; Christiansen, Frederik; Rump, Camilla

    2014-01-01

    This paper develops two sets of concepts to theorize why students engage differently in Geographical Information Systems (GIS). These theoretical concepts are used as an analytical lens to explore empirical data on the experiences and engagement of students enrolled in an undergraduate GIS course in planning and management. The analysis shows that…

  10. Engaging Students in Online Activities

    DEFF Research Database (Denmark)

    Egendal, Jeppe Michael

    This study investegates how the educational design of online study activities affects students’ social and academic engagement in connection to their study? The study uses a hermenutical approach, using recordings of online sessions of student collaborations and interviews with students as methods...... for understanding student engagement...

  11. Work engagement: drivers and effects

    NARCIS (Netherlands)

    Bakhuys Roozeboom, M.M.C.; Schelvis, R.

    2014-01-01

    The concept of work engagement fits into the tradition of positive psychology, a recent paradigm shift in psychology which focuses on mental health rather than mental illness. This article gives an introduction to the concept of work engagement. Different definitions and viewpoints of the work

  12. Student Engagement in Inclusive Classrooms

    Science.gov (United States)

    Rangvid, Beatrice Schindler

    2018-01-01

    Using large scale survey data, I document substantial differences in behavioural engagement (defined as involvement in academic and social activities, cooperative participation in learning, and motivation and effort) and emotional engagement levels (defined as a sense of belonging and well-being at school) between students with and without special…

  13. Collaborative Stakeholder Engagement. Special Report

    Science.gov (United States)

    Jordan, Matt; Chrislip, David; Workman, Emily

    2016-01-01

    Stakeholder engagement and collaboration are essential to the development of an effective state plan. Engaging a diverse group of stakeholders tasked with working together to create education policies that will have a positive, lasting impact on students is not as easy as it sounds. Experts in the field argue that the traditional stakeholder…

  14. Student Engagement through Digital Data

    Science.gov (United States)

    Gross, Liz; Meriwether, Jason L.

    2016-01-01

    This chapter suggests strategies and tools for student affairs professionals to leverage digital data to measure student engagement and learning outcomes, and refine programs that enhance institutional reputation and improve student persistence. The construct of student engagement is traced from its theoretical origins to recent research…

  15. Group conflict and faculty engagement

    DEFF Research Database (Denmark)

    Selmer, Jan; Jonasson, Charlotte; Lauring, Jakob

    2013-01-01

    In educational settings, substantial scholarly interest has focused on student engagement as an antecedent for educational development and positive school outcomes. Very limited research, however, has focused on the engagement of academic staff members. This may be a crucial oversight because...

  16. Adding Value: Online Student Engagement

    Science.gov (United States)

    Everett, Donna R.

    2015-01-01

    This paper seeks to add to the emerging literature related to online student engagement with additional suggestions for instructional strategies. Student engagement is one of the tenets of effective online instruction; as such, particular attention to how it adds value to student learning is crucial and worth the time and effort to enhance…

  17. Student Engagement: Rhetoric and Reality

    Science.gov (United States)

    Baron, Paula; Corbin, Lillian

    2012-01-01

    Recently, there has been much interest in higher education literature and policy on the concepts of student engagement and disengagement. While most academic writings recognise the significance of student engagement, they have tended to concentrate on it in relation to academic activities. Increasingly, universities are "cascading" down…

  18. Public Engagement in Energy Research

    NARCIS (Netherlands)

    Jellema, Jako; Mulder, Henk A. J.

    Public Engagement in Research is a key element in "Responsible Research and Innovation"; a cross-cutting issue in current European research funding. Public engagement can advance energy R&D, by delivering results that are more in-line with society's views and demands; and collaboration also unlocks

  19. Research staff and public engagement

    DEFF Research Database (Denmark)

    Davies, Sarah Rachael

    2013-01-01

    focuses on one staff group, contract researchers, to explore the perceived challenges and opportunities of public engagement. Qualitative and quantitative data-from a web-based survey and three focus groups-are used to show that, while engagement activities are often seen as rewarding, the challenges...

  20. Who Engages with Moral Beauty?

    Science.gov (United States)

    Diessner, Rhett; Iyer, Ravi; Smith, Meghan M.; Haidt, Jonathan

    2013-01-01

    Aristotle considered moral beauty to be the "telos" of the human virtues. Displays of moral beauty have been shown to elicit the moral emotion of elevation and cause a desire to become a better person and to engage in prosocial behavior. Study 1 ("N" = 5380) shows engagement with moral beauty is related to several psychological…

  1. Effect of plastic strain on elastic-plastic fracture toughness of SM490 carbon steel. Assessment by stress-based criterion for ductile crack initiation

    International Nuclear Information System (INIS)

    Kamaya, Masayuki

    2012-01-01

    Although the plastic strain induced in materials increases the mechanical strength, it may reduce the fracture toughness. In this study, the change in fracture toughness of SM490 carbon steel due to pre-straining was investigated using a stress-based criterion for ductile crack initiation. The specimens with blunt notch of various radiuses were used in addition to those with conventional fatigue pre-cracking. The degree of applied plastic strain was 5%, 10% or 20%. The fracture toughness was largest when the induced plastic strain was 5%, although it decreased for the plastic strains of 10% and 20%. The stress and strain distributions near the crack tip of fracture toughness test specimens was investigated by elastic-plastic finite element analyses using a well-correlated stress-strain curve for large strain. It was shown that the critical condition at the onset of the ductile crack was better correlated with the equivalent stress than the plastic strain at the crack tip. By using the stress-based criterion, which was represented by the equivalent stress and stress triaxiality, the change in the fracture toughness due to pre-straining could be reasonably explained. Based on these results, it was concluded that the stress-based criterion should be used for predicting the ductile crack initiation. (author)

  2. A unique criterion for the classification of the activity of radioactive effluents according to the activity

    International Nuclear Information System (INIS)

    Tasovac, T.; Bojovic, P.; Svabic, A.

    1964-10-01

    The present classification of radioactive effluents into categories, i.e. low, medium, high and very high activity, has not been given a definite criterion. Therefore, some categories include specific activities from 2-6 and more potentials. Therefore, it occurs that the category of medium active effluents in one nuclear center is indicated as low active in the second or as highly active in the third. Therefore, a proposal is given in this paper for a unique criterion for the classification of radioactive effluents according to their activities. This proposal is based on the decontamination factors obtained by various methods and the maximum permissible concentrations of radioactive isotopes in water (author)

  3. Specific strain work as a failure criterion in plane stress state

    International Nuclear Information System (INIS)

    Zuchowski, R.; Zietkowski, L.

    1985-01-01

    An experimental verification of failure criterion based on specific strain work was performed. Thin-walled cylindrical specimens were examined by loading with constant force and constant torque moment, assuming different values for particular tests, at the same time keeping stress intensity constant, and by subjecting to thermal cycling. It was found that the critical value of failure did not depend on axial-to-shearing stresses ratio, i.e., on the type of state of stress. Thereby, the validity of the analysed failure criterion in plane stress was confirmed. Besides, a simple description of damage development in plane stress was suggested. (orig./RF)

  4. Application of controllable unit approach (CUA) to performance-criterion-based nuclear material control and accounting

    International Nuclear Information System (INIS)

    Foster, K.W.; Rogers, D.R.

    1979-01-01

    The Nuclear Regulatory Commission is considering the use of maximum-loss performance criteria as a means of controlling SNM in nuclear plants. The Controllable Unit Approach to material control and accounting (CUA) was developed by Mound to determine the feasibility of controlling a plant to a performance criterion. The concept was tested with the proposed Anderson, SC, mixed-oxide plant, and it was shown that CUA is indeed a feasible method for controlling a complex process to a performance criterion. The application of CUA to an actual low-enrichment plant to assist the NRC in establishing performance criteria for uranium processes is discussed. 5 refs

  5. Discussion on verification criterion and method of human factors engineering for nuclear power plant controller

    International Nuclear Information System (INIS)

    Yang Hualong; Liu Yanzi; Jia Ming; Huang Weijun

    2014-01-01

    In order to prevent or reduce human error and ensure the safe operation of nuclear power plants, control device should be verified from the perspective of human factors engineering (HFE). The domestic and international human factors engineering guidelines about nuclear power plant controller were considered, the verification criterion and method of human factors engineering for nuclear power plant controller were discussed and the application examples were provided for reference in this paper. The results show that the appropriate verification criterion and method should be selected to ensure the objectivity and accuracy of the conclusion. (authors)

  6. On the gap-opening criterion of migrating planets in protoplanetary disks

    OpenAIRE

    Malik, Matej; Meru, Farzana; Mayer, Lucio; Meyer, Michael R.

    2015-01-01

    We perform two-dimensional hydrodynamical simulations to quantitatively explore the torque balance criterion for gap-opening (as formulated by Crida et al.) in a variety of disks when considering a migrating planet. We find that even when the criterion is satisfied, there are instances when planets still do not open gaps. We stress that gap-opening is not only dependent on whether a planet has the ability to open a gap, but whether it can do so quickly enough. This can be expressed as an addi...

  7. Valence electron structure of cast iron and graphltization behaviour criterion of elements

    Institute of Scientific and Technical Information of China (English)

    刘志林; 李志林; 孙振国; 杨晓平; 陈敏

    1995-01-01

    The valence electron structure of common alloy elements in phases of cast iron is calculated- The relationship between the electron structure of alloy elements and equilibrium, non-equilibrium solidification and graphitization is revealed by defining the bond energy of the strongest bond in a phase as structure formation factor S. A criterion of graphitization behaviour of elements is advanced with the critical value of the structure formation factor of graphite and the n of the strongest covalent bond in cementite. It is found that this theory conforms to practice very well when the criterion is applied to the common alloy elements.

  8. Generalized statistical criterion for distinguishing random optical groupings from physical multiple systems

    International Nuclear Information System (INIS)

    Anosova, Z.P.

    1988-01-01

    A statistical criterion is proposed for distinguishing between random and physical groupings of stars and galaxies. The criterion is applied to nearby wide multiple stars, triplets of galaxies in the list of Karachentsev, Karachentseva, and Shcherbanovskii, and double galaxies in the list of Dahari, in which the principal components are Seyfert galaxies. Systems that are almost certainly physical, probably physical, probably optical, and almost certainly optical are identified. The limiting difference between the radial velocities of the components of physical multiple galaxies is estimated

  9. Exploring DSM-5 criterion A in Acute Stress Disorder symptoms following natural disaster.

    Science.gov (United States)

    Lavenda, Osnat; Grossman, Ephraim S; Ben-Ezra, Menachem; Hoffman, Yaakov

    2017-10-01

    The present study examines the DSM-5 Acute Stress Disorder (ASD) diagnostic criteria of exposure, in the context of a natural disaster. The study is based on the reports of 1001 Filipinos following the aftermath of super typhoon Haiyan in 2013. Participants reported exposure to injury, psychological distress and ASD symptoms. Findings indicated the association of criterion A with the prevalence of meeting all other ASD diagnostic criteria and high psychological distress. The diagnostic properties of Criterion A are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. LMFBR safety criteria: cost-benefit considerations under the constraint of an a priori risk criterion

    International Nuclear Information System (INIS)

    Hartung, J.

    1979-01-01

    The role of cost-benefit considerations and a priori risk criteria as determinants of Core Disruptive Accident (CDA)-related safety criteria for large LMFBR's is explored with the aid of quantitative risk and probabilistic analysis methods. A methodology is described which allows a large number of design and siting alternatives to be traded off against each other with the goal of minimizing energy generation costs subject to the constraint of both an a priori risk criterion and a cost-benefit criterion. Application of this methodology to a specific LMFBR design project is described and the results are discussed. 5 refs

  11. Contributions of Work-Related Stress and Emotional Intelligence to Teacher Engagement: Additive and Interactive Effects.

    Science.gov (United States)

    Mérida-López, Sergio; Extremera, Natalio; Rey, Lourdes

    2017-09-29

    This study examined the additive and interactive effects of role stress and emotional intelligence for predicting engagement among 288 teachers. Emotional intelligence and engagement were positively associated. Role ambiguity and role conflict showed negative associations with vigor and dedication scores. The interaction of role ambiguity and emotional intelligence was significant in explaining engagement dimensions. Similar results were found considering overall teacher engagement. Emotional intelligence boosted engagement when the levels of role ambiguity were higher. Our findings suggest the need for future research examining the impact of job hindrances on the links between emotional intelligence and teachers' occupational well-being indicators. Finally, the implications for emotional intelligence training in education are discussed.

  12. fracture criterion

    Indian Academy of Sciences (India)

    “we never test the strength of glass: all we test is the weakness of its surface” J. T. ... 300. 400. 500. 600. Temperature, T ( C). Supercooled Liquid. Regime ... H eat F low. (m. W. ) Pd40Ni10Cu30P20. PDF Create! 5 Trial www.nuance.com ...

  13. “INFLUENCE OF BASIC MOTOR ABILITIES AND CONOTIVE CRITERION ON RESULTS OF SUCCESS IN SOME SPORTS GAMES FOR STUDENTS OF TEACHING SCHOOL”

    Directory of Open Access Journals (Sweden)

    Midhat Mekić

    2008-08-01

    Full Text Available Upon the results of research it is possible to conclude that high level of influence of basic motor abilities and conotive criterion for successive results of sports games. Dominative predictions of values had conatice characteristic (A1,L17 and one test for judgment of explosiveness of lower extremities. For above mentioned results of this research, first of all, main values of defining hypothesis for further research, as well as promotion of education-teaching process of sports games in high schools.

  14. Corrections for criterion reliability in validity generalization: The consistency of Hermes, the utility of Midas

    Directory of Open Access Journals (Sweden)

    Jesús F. Salgado

    2016-04-01

    Full Text Available There is criticism in the literature about the use of interrater coefficients to correct for criterion reliability in validity generalization (VG studies and disputing whether .52 is an accurate and non-dubious estimate of interrater reliability of overall job performance (OJP ratings. We present a second-order meta-analysis of three independent meta-analytic studies of the interrater reliability of job performance ratings and make a number of comments and reflections on LeBreton et al.s paper. The results of our meta-analysis indicate that the interrater reliability for a single rater is .52 (k = 66, N = 18,582, SD = .105. Our main conclusions are: (a the value of .52 is an accurate estimate of the interrater reliability of overall job performance for a single rater; (b it is not reasonable to conclude that past VG studies that used .52 as the criterion reliability value have a less than secure statistical foundation; (c based on interrater reliability, test-retest reliability, and coefficient alpha, supervisor ratings are a useful and appropriate measure of job performance and can be confidently used as a criterion; (d validity correction for criterion unreliability has been unanimously recommended by "classical" psychometricians and I/O psychologists as the proper way to estimate predictor validity, and is still recommended at present; (e the substantive contribution of VG procedures to inform HRM practices in organizations should not be lost in these technical points of debate.

  15. On the regularity criterion of weak solutions for the 3D MHD equations

    Science.gov (United States)

    Gala, Sadek; Ragusa, Maria Alessandra

    2017-12-01

    The paper deals with the 3D incompressible MHD equations and aims at improving a regularity criterion in terms of the horizontal gradient of velocity and magnetic field. It is proved that the weak solution ( u, b) becomes regular provided that ( \

  16. A new criterion for global robust stability of interval neural networks with discrete time delays

    International Nuclear Information System (INIS)

    Li Chuandong; Chen Jinyu; Huang Tingwen

    2007-01-01

    This paper further studies global robust stability of a class of interval neural networks with discrete time delays. By introducing an equivalent transformation of interval matrices, a new criterion on global robust stability is established. In comparison with the results reported in the literature, the proposed approach leads to results with less restrictive conditions. Numerical examples are also worked through to illustrate our results

  17. Person fit and criterion-related validity: an extension of the Schmitt, Cortina, and Whitney study

    NARCIS (Netherlands)

    Meijer, R.R.

    1997-01-01

    The effect on criterion-related validity of nonfitting response vectors (NRVs) on a predictor test was investigated. Using simulated data, it was shown that there was a substantial decrease in validity when the type of misfit was severe (i.e., guessing the correct answers to all test items), when

  18. Entanglement in SU(2)-invariant quantum systems: The positive partial transpose criterion and others

    International Nuclear Information System (INIS)

    Schliemann, John

    2005-01-01

    We study entanglement in mixed bipartite quantum states which are invariant under simultaneous SU(2) transformations in both subsystems. Previous results on the behavior of such states under partial transposition are substantially extended. The spectrum of the partial transpose of a given SU(2)-invariant density matrix ρ is entirely determined by the diagonal elements of ρ in a basis of tensor-product states of both spins with respect to a common quantization axis. We construct a set of operators which act as entanglement witnesses on SU(2)-invariant states. A sufficient criterion for ρ having a negative partial transpose is derived in terms of a simple spin correlator. The same condition is a necessary criterion for the partial transpose to have the maximum number of negative eigenvalues. Moreover, we derive a series of sum rules which uniquely determine the eigenvalues of the partial transpose in terms of a system of linear equations. Finally we compare our findings with other entanglement criteria including the reduction criterion, the majorization criterion, and the recently proposed local uncertainty relations

  19. Relationships between Classroom Schedule Types and Performance on the Algebra I Criterion-Referenced Test

    Science.gov (United States)

    Murray, Gregory V.; Moyer-Packenham, Patricia S.

    2014-01-01

    One option for length of individual mathematics class periods is the schedule type selected for Algebra I classes. This study examined the relationship between student achievement, as indicated by Algebra I Criterion-Referenced Test scores, and the schedule type for Algebra I classes. Data obtained from the Utah State Office of Education included…

  20. When non-Gaussian states are Gaussian: Generalization of nonseparability criterion for continuous variables

    International Nuclear Information System (INIS)

    McHugh, Derek; Buzek, Vladimir; Ziman, Mario

    2006-01-01

    We present a class of non-Gaussian two-mode continuous-variable states for which the separability criterion for Gaussian states can be employed to detect whether they are separable or not. These states reduce to the two-mode Gaussian states as a special case