Modeling study of rarefied gas effects on hypersonic reacting stagnation flows

Science.gov (United States)

Wang, Zhihui; Bao, Lin

2014-12-01

Recent development of the near space hypersonic sharp leading vehicles has raised a necessity to fast and accurately predict the aeroheating in hypersonic rarefied flows, which challenges our understanding of the aerothermodynamics and aerothermochemistry. The present flow and heat transfer problem involves complex rarefied gas effects and nonequilibrium real gas effects which are beyond the scope of the traditional prediction theory based on the continuum hypothesis and equilibrium assumption. As a typical example, it has been found that the classical Fay-Riddell equation fails to predict the stagnation point heat flux, when the flow is either rarefied or chemical nonequilibrium. In order to design a more general theory covering the rarefied reacting flow cases, an intuitive model is proposed in this paper to describe the nonequilibrium dissociation-recombination flow along the stagnation streamline towards a slightly blunted nose in hypersonic rarefied flows. Some characteristic flow parameters are introduced, and based on these parameters, an explicitly analytical bridging function is established to correct the traditional theory to accurately predict the actual aeroheating performance. It is shown that for a small size nose in medium density flows, the flow at the outer edge of the stagnation point boundary layer could be highly nonequilibrium, and the aeroheating performance is distinguished from that of the big blunt body reentry flows at high altitudes. As a result, when the rarefied gas effects and the nonequilibrium real gas effects are both significant, the classical similarity law could be questionable, and it is inadequate to directly analogize results from the classical blunt body reentry problems to the present new generation sharp-leading vehicles. In addition, the direct simulation Monte Carlo method is also employed to validate the conclusion.

Using absolute x-ray spectral measurements to infer stagnation conditions in ICF implosions

Science.gov (United States)

Patel, Pravesh; Benedetti, L. R.; Cerjan, C.; Clark, D. S.; Hurricane, O. A.; Izumi, N.; Jarrott, L. C.; Khan, S.; Kritcher, A. L.; Ma, T.; Macphee, A. G.; Landen, O.; Spears, B. K.; Springer, P. T.

2016-10-01

Measurements of the continuum x-ray spectrum emitted from the hot-spot of an ICF implosion can be used to infer a number thermodynamic properties at stagnation including temperature, pressure, and hot-spot mix. In deuterium-tritium (DT) layered implosion experiments on the National Ignition Facility (NIF) we field a number of x-ray diagnostics that provide spatial, temporal, and spectrally-resolved measurements of the radiated x-ray emission. We report on analysis of these measurements using a 1-D hot-spot model to infer thermodynamic properties at stagnation. We compare these to similar properties that can be derived from DT fusion neutron measurements. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Turbulence modeling and surface heat transfer in a stagnation flow region

Science.gov (United States)

Wang, C. R.; Yeh, F. C.

1987-01-01

Analysis for the turbulent flow field and the effect of freestream turbulence on the surface heat transfer rate of a stagnation flow is presented. The emphasis is on modeling and its augmentation of surface heat transfer rate. The flow field considered is the region near the forward stagnation point of a circular cylinder in a uniform turbulent mean flow.

Reference Structures: Stagnation, Progress, and Future Challenges.

Science.gov (United States)

Greenberg, Jane

1997-01-01

Assesses the current state of reference structures in online public access catalogs (OPACs) in a framework defined by stagnation, progress, and future challenges. Outlines six areas for reference structure development. Twenty figures provide illustrations. (AEF)

[Expressions of neurotransmitters in patients of insomnia differentiated as liver stagnation transforming into fire treated with acupuncture].

Science.gov (United States)

Ji, Xiangdong; Wang, Qunsong; Zhu, Wenxian

2015-06-01

To compare the difference in the efficacy between acupuncture and oral administration of trazodone and the expressions of neurotransmitters in patients of insomnia differentiated as liver stagnation transforming into fire. Seventy patients of insomnia differentiated as liver stagnation transforming into fire were randomized into an observation group and a control group, 35 cases in each one. In the observation group, acupuncture therapy was adopted at Shenmen (HT 7), Baihui (GV 20), Yintang (GV 29), Hegu (LI 4), Taichong (LR 3), etc. The needles were retained for 20 min each time. The treatment was given once a day, the treatment of 2 weeks made one session. In the control group, trazodone, 100 mg, oral administration, once a day, the treatment of 2 weeks made one session. Two sessions were required in the two groups. The scores in Pittsburgh sleep quality index (PSQI) and Asberg rating scale for side effects (SERS), the levels of neurotransmitters such as 5-hydroxy tryptamine (5-HT) and norepinephrine (NE) and the expressions of protein kinase C (PKC) and brain-derived neurotrophic factor (BDNF) in peripheral blood were observed before and after treatment in the two groups. PSQI score and SERS score after treatment were all decreased compared with those in both groups before treatment (both Pinsomnia differentiated as liver stagnation transforming into fire, and reduces serum NE level and increases 5-HT content and BDNF expression, which achieves the better efficacy as compared with the oral administration of trazodone. It is one of the effective approaches to the treatment of insomnia differentiated as liver stagnation transforming into fire.

Effect of ablation geometry on the formation of stagnation layer in laterally colliding plasmas

International Nuclear Information System (INIS)

Mondal, Alamgir; Singh, Rajesh K.; Kumar, Ajai

2015-01-01

Interaction between two parallel propagating plasma plumes have been investigated in two different ablation schemes e.g. laser-blow-off (LBO) of thin film and conventional laser ablation (LPP). Fast imagine technique is used to study the dynamical and geometrical aspect of seed plasmas and induced stagnation layer in between the two expanding seed plasmas. Interaction between the energetic particles, coming from the seed plasmas are responsible for formation of stagnation layer. It has been found that geometrical shape, size, kinetic energy and divergence of plasma plumes are highly dependent on the ablation geometry. These variations in seed plasmas initiate the significant differences in the stagnation layer formed by LBO and LPP geometry. In this presentation, characteristic feature of stagnation layer which includes density, initiation time, emissive life time and geometry in both LBO and LPP geometry are briefly discussed. A comparative study of present results suggests that the plume composition and directionality of seed plasma play crucial role in mechanistic aspect of stagnation layer. (author)

Nested separatrices in simple shear flows: the effect of localized disturbances on stagnation lines

OpenAIRE

Wilson, M.C.T.; Gaskell, P.H.; Savage, M.D.

2005-01-01

The effects of localized two-dimensional disturbances on the structure of shear flows featuring a stagnation line are investigated. A simple superposition of a planar Couette flow and Moffatt's [J. Fluid Mech. 18, 1--18 (1964)] streamfunction for the decay of a disturbance between infinite stationary parallel plates shows that in general the stagnation line is replaced by a chain of alternating elliptic and hyperbolic stagnation points with a separation equal to 2.78 times the half-gap betwee...

Climatic and technological ceilings for Chinese rice stagnation based on yield gaps and yield trend pattern analysis.

Science.gov (United States)

Zhang, Tianyi; Yang, Xiaoguang; Wang, Hesong; Li, Yong; Ye, Qing

2014-04-01

Climatic or technological ceilings could cause yield stagnation. Thus, identifying the principal reasons for yield stagnation within the context of the local climate and socio-economic conditions are essential for informing regional agricultural policies. In this study, we identified the climatic and technological ceilings for seven rice-production regions in China based on yield gaps and on a yield trend pattern analysis for the period 1980-2010. The results indicate that 54.9% of the counties sampled experienced yield stagnation since the 1980. The potential yield ceilings in northern and eastern China decreased to a greater extent than in other regions due to the accompanying climate effects of increases in temperature and decreases in radiation. This may be associated with yield stagnation and halt occurring in approximately 49.8-57.0% of the sampled counties in these areas. South-western China exhibited a promising scope for yield improvement, showing the greatest yield gap (30.6%), whereas the yields were stagnant in 58.4% of the sampled counties. This finding suggests that efforts to overcome the technological ceiling must be given priority so that the available exploitable yield gap can be achieved. North-eastern China, however, represents a noteworthy exception. In the north-central area of this region, climate change has increased the yield potential ceiling, and this increase has been accompanied by the most rapid increase in actual yield: 1.02 ton ha(-1) per decade. Therefore, north-eastern China shows a great potential for rice production, which is favoured by the current climate conditions and available technology level. Additional environmentally friendly economic incentives might be considered in this region. © 2013 John Wiley & Sons Ltd.

Efficient solution to the stagnation problem of the particle swarm optimization algorithm for phase diversity.

Science.gov (United States)

Qi, Xin; Ju, Guohao; Xu, Shuyan

2018-04-10

The phase diversity (PD) technique needs optimization algorithms to minimize the error metric and find the global minimum. Particle swarm optimization (PSO) is very suitable for PD due to its simple structure, fast convergence, and global searching ability. However, the traditional PSO algorithm for PD still suffers from the stagnation problem (premature convergence), which can result in a wrong solution. In this paper, the stagnation problem of the traditional PSO algorithm for PD is illustrated first. Then, an explicit strategy is proposed to solve this problem, based on an in-depth understanding of the inherent optimization mechanism of the PSO algorithm. Specifically, a criterion is proposed to detect premature convergence; then a redistributing mechanism is proposed to prevent premature convergence. To improve the efficiency of this redistributing mechanism, randomized Halton sequences are further introduced to ensure the uniform distribution and randomness of the redistributed particles in the search space. Simulation results show that this strategy can effectively solve the stagnation problem of the PSO algorithm for PD, especially for large-scale and high-dimension wavefront sensing and noisy conditions. This work is further verified by an experiment. This work can improve the robustness and performance of PD wavefront sensing.

Public debt, secular stagnation and functional finance

DEFF Research Database (Denmark)

Skott, Peter

2016-01-01

Fiscal policy and public debt may be required to maintain full employment and avoid secular stagnation. This conclusion emerges from a range of different models, including OLG specifications and stock-flow consistent (post-) Keynesian models. One of the determinants of the required long-run debt ...

Energy-political stagnation or innovation

International Nuclear Information System (INIS)

Kitschelt, H.

1982-01-01

The author discusses the enquete report 1980. He makes an inventory for a political and sociological interpretation of the interim report between meaningful innovation and political insignificance as well as intellectual stagnation. The report is considered as an indicator for the transformation of the energy-political arena in the Federal Republic of Germany over the last years. ''Stagnation'' or ''innovation'' of the argumentation patterns in the report of the enquete commission relate to the question whether the analyses in that document are rather a brake or a motor to a shift of political perspectives in energy policy. A progress can be seen in the report regarding political debate about energy-options in the semi-official political spectrum of the Federal Republic of Germany, in as far as differring options of energy-political development are being acknowledged for the first time. At the same time, debate inside the commission directs the attention to issues of institutional policy in the energy sector. Considering the fights within the commission before the report was agreed on, it seems doubtful if its proposals for compromise will prove a sound political basis. The tensions inside the commission are just a first sign of the power conflicts due above all if the recommendations for energy conservation are intransigently carried out. (orig./HSCH) [de

Stagnating energy efficiency in the Swedish building sector-Economic and organisational explanations

International Nuclear Information System (INIS)

Naessen, Jonas; Sprei, Frances; Holmberg, John

2008-01-01

The development towards higher energy efficiency in the Swedish building sector stagnated in the late 1980s and 1990s. In new buildings the average specific energy use for heating is twice as high as in the best performing buildings 20 years ago. By combining econometric studies and interviews with actors in the building sector we analyse the underlying economic and organisational causes for this development. In the stock of buildings, specific energy use for heating (kWh/m 2 /yr) has a high correlation with increasing energy prices and price elasticities have not changed markedly over time. This implies that the stagnation to a large extent can be explained by energy price trends. On the contrary, in new buildings the correlation between energy prices and specific energy use is much weaker. One important cause of low sensitivity to price changes is that information about the life cycle cost (LCC) of different investment alternatives is often not available to the involved actors. The most common investment criterion is instead the requirements of the national building energy standard which has developed into a norm rather than a minimum for energy performance. In this paper we also discuss potential improvements in the learning processes within the sector

Solar wind stagnation near comets

International Nuclear Information System (INIS)

Galeev, A.A.; Cravens, T.E.; Gombosi, T.I.

1983-03-01

The nature of the solar wind flow near comets is examined analytically. In particular, the typical values for the stagnation pressure and magnetic barrier strength are estimated, taking into account the magnetic field line tension and the charge exchange cooling of the mass loaded solar wind. Knowledge of the strength of the magnetic barrier is required in order to determine the location of the contact discontinuity which separates the contaminated solar wind plasma and the outflowing plasma of the cometary ionosphere. (author)

THERMOSS: A thermohydraulic model of flow stagnation in a horizontal fuel channel

International Nuclear Information System (INIS)

Gulshani, P.; Caplan, M.Z.; Spinks, N.J.

1984-01-01

A model, called THERMOSS, is developed to compute the duration of stagnation in a CANDU reactor fuel channel with subcooled, stagnant initial conditions. The model solves, in closed form, the one dimensional, two-fluid conservation equations. In the computation of the duration of stagnation, the channel water level is an important intermediate variable because it determines the amount of steam production. A feature of the model is that water level is determined by a momentum balance between frictional pressure drop in the steam phase and hydrostatic head in the liquid phase. This is in contrast to an ealier model in which the level was determined from mass balance considerations. A satisfactory agreement between the predicted and experimentally observed channel water level and duration of stagnation is obtained. (orig.)

Aggregate demand, functional finance and secular stagnation

DEFF Research Database (Denmark)

Skott, Peter

2016-01-01

This paper makes three main points. Fiscal policy, first, may be needed in the long run to maintain full employment and avoid secular stagnation. If fiscal policy is used in this way, second, the long-run debt ratio depends (i) inversely on the rate of growth, (ii) inversely on government consump...

Implications of the stagnation line model for energy input through the dayside magnetopause

International Nuclear Information System (INIS)

Pudovkin, M.I.; Semenov, V.S.; Heyn, M.F.; Biernat, H.K.

1986-01-01

Based on the formation of a stagnation line at the magnetopause the electromagnetic energy transport from the solar wind into the dayside magnetosphere is analyzed. The resulting energy flux is analyzed. The resulting energy flux is proportional to v/sub infinity/B/sub infinity/sin 2 (theta/sub infinity/-phi/sub infinity/), where v/sub infinity/ and B/sub infinity/ are the solar wind speed and magnetic field and theta/sub infinity/-phi/sub s/infinity is the angle between the IMF and the stagnation line projected into the interplanetary space. A stagnation line parallel to the separator gives approximately the sin 4 (theta/sub infinity//2) energy flux dependence of Akasofu's epsilon-index

Wage Dispersion, Public Sector Wages and the Stagnating Danish Gender Wage Gap

DEFF Research Database (Denmark)

Gupta, Nabanita Datta; Oaxaca, Ronald L.; Smith, Nina

1998-01-01

The gender wage gap in Denmark has virtually stagnated since the early 70s. This study examines whether this stagnation is mainly due to a changing wage dispersion or to changing prices on observed and unobserved skills. Since about half the female labour force is employed in the public sector....... These techniques are applied to a sample of Danish wage earners in the period 1983-94. The decomposition results suggest different explanations behind the stagnation of the gender wage gap in the public and private sectors. The development in average public sector wages is calculated assuming observed......, the impact of the changing wage structure between the public and private sectors is investigated. The analysis is based on the Juhn-Murphy-Pierce decomposition applied to a pooled wage regression model. The equivalence between the former and the Oaxaca-Ransom generalized wage decomposition is established...

Swedish district heating—A system in stagnation: Current and future trends in the district heating sector

International Nuclear Information System (INIS)

Magnusson, Dick

2012-01-01

This paper argues that Sweden’s old and established district heating sector is heading into a stagnation phase. The aim is to analyse the factors influencing this development as well as the strategies used by involved parties to prevent stagnation. Using large technical system theory, I analyse internal and external factors potentially causing stagnation. The most obvious external factors are: an increase in the number of energy-efficient buildings, in response to stricter energy policies, which reduces the future potential for district heating in new and existing buildings; climate change; competition from other heating systems; and market saturation in the key sector, multi-dwelling buildings. The main internal factor is changed business strategies following electricity market deregulation, when energy companies were supposed to be run on businesslike terms. I also argue that stagnation can be defined as occurring when the key measure feature of a system, in this case, heat load is starting to stagnate or decline, even though the trend is positive in other areas. The strategies for avoiding stagnation are various forms of broadening scope, primarily by focusing more on electricity production by building combined heat and power plants, or using the alternative value of the technical system for new applications. - Highlights: ► The Swedish district heating sector is heading into a stage of stagnation. ► The main reasons are: climate change, competition and energy efficient buildings. ► Strategies to change trend: broadening of scope by focusing on electricity in CHP plants. ► Contribution to Large Technical Systems—theory and the later phases of system development.

RELAP4 stagnation properties option

International Nuclear Information System (INIS)

DeYoung, T.L.

1979-01-01

The stagnation properties option in RELAP4/MOD6 was completely reviewed, from theoretical foundation to code application. The result of this investigation was the identification of a fundamental mismatch between the essentially homogeneous, equilibrium-based, RELAP4 code and the nonhomogeneous and/or nonequilibrium critical flow models imposed on the code. By continuously monitoring fluid Mach numbers and adjusting flow areas such that sonic velocity was never exceeded, the mismatch could be accommodated. This approach was implemented, found to work correctly, and will be incorporated into the MOD7 version of the code

Effect of outer stagnation pressure on jet structure in supersonic coaxial jet

International Nuclear Information System (INIS)

Kim, Myoung Jong; Woo, Sang Woo; Lee, Byeong Eun; Kwon, Soon Bum

2001-01-01

The characteristics of dual coaxial jet which composed of inner supersonic nozzle of 26500 in constant expansion rate with 1.91 design Mach number and outer converging one with 40 .deg. C converging angle with the variation of outer nozzle stagnation pressure are experimentally investigated in this paper. In which the stagnation pressure for the inner supersonic nozzle is 750kPa thus, the inner jet leaving the nozzle is slightly underexpanded. The plenum pressure of outer nozzle are varied from 200 to 600kPa. Flow visualizations by shadowgraph method, impact pressure and centerline static pressure measurements of dual coaxial jet are presented. The results show that the presence of outer jet affects significantly the structures and pressure distributions of inner jet. And outer jet causes Mach disk which does not appear for the case of single jet stream. As the stagnation pressure of outer jet increases, impact pressure undulation is severe, but the average impact pressure keeps high far downstream

Adhesion of leukocytes under oscillating stagnation point conditions: a numerical study.

Science.gov (United States)

Walker, P G; Alshorman, A A; Westwood, S; David, T

2002-01-01

Leukocyte recruitment from blood to the endothelium plays an important role in atherosclerotic plaque formation. Cells show a primary and secondary adhesive process with primary bonds responsible for capture and rolling and secondary bonds for arrest. Our objective was to investigate the role played by this process on the adhesion of leukocytes in complex flow. Cells were modelled as rigid spheres with spring like adhesion molecules which formed bonds with endothelial receptors. Models of bond kinetics and Newton's laws of motion were solved numerically to determine cell motion. Fluid force was obtained from the local shear rate obtained from a CFD simulation of the flow over a backward facing step.In stagnation point flow the shear rate near the stagnation point has a large gradient such that adherent cells in this region roll to a high shear region preventing permanent adhesion. This is enhanced if a small time dependent perturbation is imposed upon the stagnation point. For lower shear rates the cell rolling velocity may be such that secondary bonds have time to form. These bonds resist the lower fluid forces and consequently there is a relatively large permanent adhesion region.

Stagnation-point flow of second grade nanofluid towards a nonlinear stretching surface with variable thickness

Directory of Open Access Journals (Sweden)

Rai Sajjad Saif

Full Text Available This paper investigates the stagnation point flow of second grade nanomaterial towards a nonlinear stretching surface subject to variable surface thickness. The process of heat transfer is examined through the melting heat and mixed convection effects. Further novel features regarding Brownian motion and thermophoresis are present. Boundary-layer approximation is employed in the problem formulation. Momentum, energy and concentration equations are converted into the non-linear ordinary differential system through the appropriate transformations. Convergent solutions for resulting problem are computed. Behaviors of various sundry variables on temperature and concentration are studied in detail. The skin friction coefficient and heat and mass transfer rates are also computed and analyzed. Our results indicate that the temperature and concentration distributions are enhanced for larger values of thermophoresis parameter. Further the present work is hoped to be useful in improving the performance of heat transfer of base fluid. Keywords: Stagnation-point flow, Second grade fluid, Nanoparticles, Melting heat process, Nonlinear stretching surface, Variable surface thickness

Invalidating stagnation theory for family owned businesses : comparing family-to-family and third party ownership transfers

NARCIS (Netherlands)

Alija Ibrahimovic; Lex van Teeffelen; Roger Heaver

2015-01-01

Miller, Le Breton-Miller and Scholnick (2008) summarize and discuss two major perspectives constructed from the literature on family owned businesses (FOBs): stewardship and stagnation theory. In this paper the stagnation theory is being put to the test on Dutch small/medium enterprises (SMEs).

The Role of Rumination and Stressful Life Events in the Relationship between the Qi Stagnation Constitution and Depression in Women: A Moderated Mediation Model

Science.gov (United States)

Liu, Qiaosheng

2017-01-01

The qi stagnation constitution is associated with depression in traditional Chinese medicine. It is unclear how rumination and stressful life events affect the relationship between the qi stagnation constitution and depression. The Qi Stagnation Constitution Scale, Ruminative Response Scale, Center for Epidemiologic Studies Depression Scale, and Adolescent Self-Rating Life Events Checklist were used to assess this association in 1200 female college students. The results revealed that the qi stagnation constitution was positively associated with depression. Furthermore, rumination was a partial mediator of the relationship between the qi stagnation constitution and depression. In addition, stressful life events moderated the direct effect and mediating effect of the qi stagnation constitution on depression. These findings indicate that rumination and stressful life events may affect the relationship between the qi stagnation constitution and depression in women. PMID:28757889

The Role of Rumination and Stressful Life Events in the Relationship between the Qi Stagnation Constitution and Depression in Women: A Moderated Mediation Model

Directory of Open Access Journals (Sweden)

Mingfan Liu

2017-01-01

Full Text Available The qi stagnation constitution is associated with depression in traditional Chinese medicine. It is unclear how rumination and stressful life events affect the relationship between the qi stagnation constitution and depression. The Qi Stagnation Constitution Scale, Ruminative Response Scale, Center for Epidemiologic Studies Depression Scale, and Adolescent Self-Rating Life Events Checklist were used to assess this association in 1200 female college students. The results revealed that the qi stagnation constitution was positively associated with depression. Furthermore, rumination was a partial mediator of the relationship between the qi stagnation constitution and depression. In addition, stressful life events moderated the direct effect and mediating effect of the qi stagnation constitution on depression. These findings indicate that rumination and stressful life events may affect the relationship between the qi stagnation constitution and depression in women.

Changes of the corrosion potential of iron in stagnation and flow conditions and their relationship with metal release.

Science.gov (United States)

Fabbricino, Massimiliano; Korshin, Gregory V

2014-10-01

This study examined the behavior of corrosion potential (Ecorr) of iron exposed to drinking water during episodes of stagnation and flow. These measurements showed that during stagnation episodes, Ecorr values decrease prominently and consistently. This decrease is initially rapid but it becomes slower as the stagnation time increases. During flow episodes, the Ecorr values increase and reach a quasi-steady state. Experiments with varying concentrations of dissolved oxygen showed that the decrease of Ecorr values characteristic for stagnation is likely to be associated with the consumption of dissolved oxygen by the exposed metal. The corrosion potential of iron and its changes during stagnation were sensitive to the concentrations of sulfate and chloride ions. Measurements of iron release showed that both the absolute values of Ecorr measured prior to or after stagnation episodes were well correlated with the logarithms of concentrations of total iron. The slope of this dependence showed that the observed correlations between Ecorr values and Fe concentrations corresponded to the coupling between the oxidant consumption and changes of Fe redox status. These results demonstrate that in situ Ecorr measurements can be a sensitive method with which to ascertain effects of hydrodynamic conditions and short-term variations of water chemistry on metal release and corrosion in drinking water. This approach is valuable practically because Ecorr measurements are precise, can be carried out in situ with any desired time resolution, do not affect the state of exposed surface in any extent and can be carried out with readily available equipment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Variations in the Spatial Distribution of Areas of Economic Growth and Stagnation in Poland: Determinants and Consequences

Directory of Open Access Journals (Sweden)

Churski Paweł

2014-06-01

Full Text Available This study seeks to identify the spatial distribution of and changes in areas of economic growth and stagnation in Poland resulting from spatial differences in the process of the country’s socio-economic advancement. The research covered two spatial systems, NUTS 2 and NUTS 4, and embraced the following steps: (1 identification of the spatial distribution of areas of economic growth and stagnation, by region and subregion, and of its determinants; (2 analysis of variations in the spatial distribution of areas of economic growth and stagnation, by region and subregion, and of its consequences; and (3 conclusions from the development trajectories identified and recommendations for intervention measures to be taken under cohesion policy.

Estimation of Centers and Stagnation points in optical flow fields

DEFF Research Database (Denmark)

Larsen, Rasmus

1997-01-01

In a topological sense fluid flows are characterised by their stagnation points. Given a temporal sequence of images of fluids we will consider the application of local polynomials to the estimation of smooth fluid flow fields. The normal flow at intensity contours is estimated from the local dis...

Current redistribution and generation of kinetic energy in the stagnated Z pinch.

Science.gov (United States)

Ivanov, V V; Anderson, A A; Papp, D; Astanovitskiy, A L; Talbot, B R; Chittenden, J P; Niasse, N

2013-07-01

The structure of magnetic fields was investigated in stagnated wire-array Z pinches using a Faraday rotation diagnostic at the wavelength of 266 nm. The distribution of current in the pinch and trailing material was reconstructed. A significant part of current can switch from the main pinch to the trailing plasma preheated by x-ray radiation of the pinch. Secondary implosions of trailing plasma generate kinetic energy and provide enhanced heating and radiation of plasma at stagnation. Hot spots in wire-array Z pinches also provide enhanced radiation of the Z pinch. A collapse of a single hot spot radiates 1%-3% of x-ray energy of the Z pinch with a total contribution of hot spots of 10%-30%.

3D Stagnation instabilities in MagLIF loads on the Z Generator

Science.gov (United States)

Jennings, Christopher

2017-10-01

Experiments with Magnetized Liner Inertial Fusion (MagLIF) loads have successfully demonstrated the premise of magnetized fusion. While these experiments are increasingly well diagnosed, many of the measurements (particularly during stagnation) are time integrated, limited in spatial resolution or require additional assumptions to interpret in the context of a structured, rapidly evolving system. As such, there is some ambiguity over what may be limiting performance. Poor laser coupling in preheating the fuel prior to implosion has been suggested as a mechanism. Mix of high Z contaminants that cool the fuel is also a significant concern. In addition, time integrated crystal imaging has shown significant structure in the final fuel assembly indicating potential disruption from instabilities. Understanding the balance between these degradation mechanisms is vital to progress with MagLif. We compare several sets of experimental data with synthetically generated data from systematically varied 3D resistive-MHD simulations to gain insight into the relative contributions of different degradation mechanisms. We demonstrate how some measurements strongly indicate disruption from liner material penetrating into the fuel at stagnation, and discuss the implications this has for how MagLif targets work and scale to larger drive currents. We then explore the extent to which different combinations of instability development, current delivery, high-Z mix into the fuel and initial laser deposition can be differentiated in our existing measurements. Better determining the dominant degradation mechanisms can directly influence the direction we take to improve performance, or our confidence in scaling these targets to higher currents. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. DoE's NNSA under contract DE-NA0003525.

The Impact of Principal Instructional Leadership Practices on Student Achievement

Science.gov (United States)

Nason, Kristen Kendrick

2011-01-01

The problem addressed in this cross-sectional, quantitative study was a continual stagnation in student achievement in one U.S. state, which is critical to stakeholders responsible for increasing student advancement in college and the 21st century workforce. Specifically, the objective was to identify the relationship between principal-perceived…

Stagnation and interpenetration of laser-created colliding plasmas

Energy Technology Data Exchange (ETDEWEB)

Pollaine, S.M.; Albritton, J.R.; Kauffman, R.; Keane, C.J. (Lawrence Livermore National Lab., CA (USA)); Berger, R.L.; Bosch, R.; Delameter, N.D.; Failor, B.H. (KMS Fusion, Inc., Ann Arbor, MI (USA))

1990-11-05

A KMS laser experiment collides Aluminum (A1) and Magnesium (Mg) plasmas. The measurements include electron density, time and space resolved Ly-alpha and He-alpha lines of Al and Mg, and x-ray images. These measurements were analyzed with a hydrodynamic code, LASNEX, and a special two-fluid code OFIS. The results strongly suggest that at early times, the Al interpenetrates the counterstreaming Mg and deposits in the dense Mg region. At late times, the Al plasma stagnates against the Mg plasma.

The Chinese medicine construct "stagnation" in mind-body connection mediates the effects of mindfulness training on depression and anxiety.

Science.gov (United States)

Lo, Herman H M; Ng, Siu Man; Chan, Cecilia L W; Lam, K F; Lau, Bobo H P

2013-08-01

Previous studies have identified different, but highly correlated variables explaining the effects of mindfulness training. Many of them are limited by tautological explanation. Under the framework of the mind-body connection, mindfulness training cultivates body awareness and promotes self-management of illness. Stagnation, a concept from Chinese medicine, may help explain the mechanism of change in mindfulness training. Individuals with depressive and anxiety symptoms (n=82) were randomized to either a Compassion-Mindfulness Therapy (C-MT) program or a waitlist control condition. The effect of stagnation as a mediator was investigated for dependent variables including depression, anxiety, and other physical and mental health variables. Depression, anxiety, stagnation, physical distress, daily functioning, positive affect, negative affect. Compared with the participants in the control group, those who completed C-MT demonstrated significant decreases in depression, F(1, 78)=15.67, p<.001, anxiety, F(1, 78)=7.72, p<.001, stagnation, F(1, 78)=4.96, p<.001, and other body-mind-spirit well-being measures. After entering the change in stagnation as the mediator, the effect of treatment reduced: depression (.35-.22), anxiety (.33-.05), and same patterns in other three secondary measures. The Sobel test was administered and significant reductions between group and depression (z=2.18, p=.029), anxiety (z=2.21, p=.027), and three secondary other measures (p<.05) were indicated. The study provides initial support for the role of stagnation in mediating changes in mindfulness training. It adds evidence to body-mind nondualism and offers new possibilities in studying treatment process and change mechanism. Copyright © 2013 Elsevier Ltd. All rights reserved.

Recirculation, stagnation and ventilation: The 2014 legionella episode

Science.gov (United States)

Russo, Ana; Soares, Pedro M. M.; Gouveia, Célia M.; Cardoso, Rita M.; Trigo, Ricardo M.

2017-04-01

period covering the 2014 event (7-25 November 2014). Hourly zonal (u) and meridional (v) wind components were retrieved from hindcast regional climate simulation covering the whole Iberian Peninsula (IP) with a spatial resolution of 9 km. This simulation was performed with the WRF model and for this study, the u and v components were extracted for a set of 12 points of the simulation grid around Lisbon. The preliminary results regarding the average daily critical transport indices for the 1989-2007 period clearly indicate that the airshed is prone to ventilation as these events have a dominant presence through most of the study period (72%), relatively to the occurrence of recirculation (10%) and stagnation (<2%) events. Comparatively to the 1989-2007 period, the 2014 episode is truly exceptional. [1] Allwine KJ, Whiteman CD., 1994. Atmospheric Environment 28: 713-721. [2] Blystad H, Brantsæter AB, Løvoll Ø., 2005. Eurosurveillance weekly release, 10(5) [3] Nguyen T, Ilef D, Jarraud S, Rouil L, Campese C, Che D, Haeghebaert S, Ganiayre F, Marcel F, Etienne J, Desenclos J-C, 2006. The Journal of Infectious Diseases, 193, 1, 102-111. [4] Mohan M, Bhati S. 2012. Journal of Civil & Environmental Engineering, S1:003.

Hall effect on magnetohydrodynamic instabilities at an elliptic magnetic stagnation line

Science.gov (United States)

Spies, Günther O.; Faghihi, Mustafa

1987-06-01

To answer the question whether the Hall effect removes the unphysical feature of ideal magnetohydrodynamics of predicting small wavelength kink instabilities at any elliptic magnetic stagnation line, a normal mode analysis is performed of the motion of an incompressible Hall fluid about cylindrical Z-pinch equilibria with circular cross sections. The eigenvalue loci in the complex frequency plane are derived for the equilibrium with constant current density. Every particular mode becomes stable as the Hall parameter exceeds a critical value. This value, however, depends on the mode such that it increases to infinity as the ideal growth rate decreases to zero, implying that there always remains an infinite number of slowly growing instabilities. Correspondingly, the stability criterion for equilibria with arbitrary current distributions is independent of the Hall parameter.

Hall effect on magnetohydrodynamic instabilities at an elliptic magnetic stagnation line

International Nuclear Information System (INIS)

Spies, G.O.; Faghihi, M.

1987-01-01

To answer the question whether the Hall effect removes the unphysical feature of ideal magnetohydrodynamics of predicting small wavelength kink instabilities at any elliptic magnetic stagnation line, a normal mode analysis is performed of the motion of an incompressible Hall fluid about cylindrical Z-pinch equilibria with circular cross sections. The eigenvalue loci in the complex frequency plane are derived for the equilibrium with constant current density. Every particular mode becomes stable as the Hall parameter exceeds a critical value. This value, however, depends on the mode such that it increases to infinity as the ideal growth rate decreases to zero, implying that there always remains an infinite number of slowly growing instabilities. Correspondingly, the stability criterion for equilibria with arbitrary current distributions is independent of the Hall parameter

Stagnation point flow and heat transfer over a nonlinear shrinking sheet with slip effects

Directory of Open Access Journals (Sweden)

N.F. Fauzi

2015-12-01

Full Text Available In this paper, an investigation is performed to analyze the effects of the slip parameters A and B on the steady stagnation-point flow and heat transfer due to a shrinking sheet in a viscous and incompressible fluid. Using similarity transformations, the governing boundary layer equations are transformed into the nonlinear ordinary (similar differential equations. The transformed equations are solved numerically using the shooting method. The dual solutions for velocity and temperature distribution exist for certain values of the positive constant velocity and temperature slip parameters. Likewise, a stability analysis has been performed to find the nature of the dual solutions. The velocity slip will delay the boundary layer separation whereas the temperature slip does not affect the boundary layer separation.

Safe, Non-Corrosive Dielectric Fluid for Stagnating Radiator Thermal Control System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Paragon proposes to develop a single-loop, non-toxic, stagnating active pumped loop thermal control design for NASA's Orion or Lunar Surface Access Module (LSAM)...

Prediction and experimental validation of stagnation temperature attained by a solar cooker of hot box type

Energy Technology Data Exchange (ETDEWEB)

Narasimha Rao, A. V; Srikrishna, D. V. N [Warangal (India)

2000-07-01

A hot box type solar cooker, having double glass covers and a plane mirror reflector, is tested for stagnation temperature. A computer code is developed based on the analytical model proposed by Vaishya et. al. The global and beam components of solar radiation measured at Warangal are made use to predict the stagnation temperature of the cooker. The observed values of stagnation temperature at Warangal are compared with those of predicted values. A good agreement of the measured and observed values of the stagnation temperature is observed during the afternoon period. The lag in the observed values during the forenoon may be due to thermal inertia of the cooker. [Spanish] Se probo una estufa solar de tipo caja caliente con cubiertas dobles de vidrio y un espejo reflector plano para medir la temperatura de estancamiento. Se desarrollo un codigo de computacion basado en el modelo analitico propuesto por Vaishya et. al. Los componentes de la radiacion solar globales y de rayo medidos en Warangal se usan para predecir la temperatura de estancamiento de la estufa. Los valores observados de la temperatura de estancamiento en Warangal se comparan con los valores predichos. Se aprecia una buena concidencia de los valores medidos y observados de la temperatura de estancamiento durante el periodo de la tarde. El retraso de los valores observados durante la manana puede ser debido a la inercia termica de la estufa.

Modeling of Aerobrake Ballute Stagnation Point Temperature and Heat Transfer to Inflation Gas

Science.gov (United States)

Bahrami, Parviz A.

2012-01-01

A trailing Ballute drag device concept for spacecraft aerocapture is considered. A thermal model for calculation of the Ballute membrane temperature and the inflation gas temperature is developed. An algorithm capturing the most salient features of the concept is implemented. In conjunction with the thermal model, trajectory calculations for two candidate missions, Titan Explorer and Neptune Orbiter missions, are used to estimate the stagnation point temperature and the inflation gas temperature. Radiation from both sides of the membrane at the stagnation point and conduction to the inflating gas is included. The results showed that the radiation from the membrane and to a much lesser extent conduction to the inflating gas, are likely to be the controlling heat transfer mechanisms and that the increase in gas temperature due to aerodynamic heating is of secondary importance.

Growth or stagnation in pre-industrial Britain? A revealed income growth approach

DEFF Research Database (Denmark)

Groth, Christian; Persson, Karl Gunnar

2016-01-01

The extent of growth in pre-industrial Europe in general and in Britain in particular has attracted intense scholarly focus. Growth or Malthusian stagnation? No consensus has evolved. Reconstructions of national income from 1300 and up to the Industrial Revolution come to opposing conclusions...

What Explains the Stagnation of Female Labor Force Participation in Urban India?

NARCIS (Netherlands)

Klasen, S.; Pieters, J.

2015-01-01

Female labor force participation rates in urban India between 1987 and 2011 are surprisingly low and have stagnated since the late 1980s. Despite rising growth, fertility decline, and rising wage and education levels, married women's labor force participation hovered around 18 percent. Analysis of

The Augmented Performer and the Performative Augmentation

DEFF Research Database (Denmark)

Kallionpaa, Maria; Gasselseder, Hans-Peter

2016-01-01

Composers, performers, and listeners usually regard musical compositions as unchangeable entities, which limits the composition techniques and decreases the originality of performers ́ interpretations, thus leading to a stagnation of classical music culture. The significance and possibilities of ...

Effects of Gyejibongnyeong-hwan on dysmenorrhea caused by blood stagnation: study protocol for a randomized controlled trial

Directory of Open Access Journals (Sweden)

Park Jeong-Su

2012-01-01

Full Text Available Abstract Background Gyejibongnyeong-hwan (GJBNH is one of the most popular Korean medicine formulas for menstrual pain of dysmenorrhea. The concept of blood stagnation in Korean medicine is considered the main factor of causing abdominal pain, or cramps, during menstrual periods. To treat the symptoms, GJBNH is used to fluidify the stagnated blood and induce the blood flow to be smooth, reducing pain as the result. The purpose of this trial is to identify the efficacy of GJBNH in dysmenorrhea caused by blood stagnation. Methods This study is a multi-centre, randomised, double-blind, controlled trial with two parallel arms: the group taking GJBNH and the group taking placebo. 100 patients (women from age 18 to 35 will be enrolled to the trial. Through randomization 50 patients will be in experiment arm, and the other 50 patients will be in control arm. At the second visit (baseline, all participants who were already screened that they fulfil both the inclusion and the exclusion criteria will be randomised into two groups. Each group will take the intervention three times per day during two menstrual cycles. After the treatment for two cycles, each patient will be followed up during their 3rd, 4th and 5th menstrual cycles. From the screening (Visit 1 through the second follow-up (Visit 6 the entire process will take 25 weeks. Discussion This trial will provide evidence for the effectiveness of GJBNH in treating periodical pain due to dysmenorrhea that is caused by blood stagnation. The primary outcome between the two groups will be measured by changes in the Visual Analogue Score (VAS of pain. The secondary outcome will be measured by the Blood Stagnation Scale, the Short-form McGill questionnaire and the COX menstrual symptom scale. Analysis of covariance (ANCOVA and repeated measured ANOVA will be used to analyze the data analysis. Trial registration Current Controlled Trials: ISRCTN30426947

Constraining the timescale of magma stagnation beneath Mauna Kea volcano, Hawaii,using diffusion profiles in olivine phenocrysts

Science.gov (United States)

Bloch, E. M.; Ganguly, J.

2009-12-01

Fe-Mg diffusion profiles have been measured in olivine xenocrysts within alkalic basalts in order to constrain the timescales of magma stagnation beneath Mauna Kea volcano, Hawaii. It has been suggested that during the main tholeiitic shield-building stage, and postshield eruptive stages of Mauna Kea, magmas were stalled and stagnated near the Moho, at a depth of ~15 km. Evidence in support of this hypothesis comes from cumulates formed by gravity-settling and in situ crystallization within magma chambers (Fodor and Galar, 1997), and from clinopyroxene-wholerock thermobarometry on Hamakua basalts (Putirka, in press). The cumulates represent a ‘fossil’ magma chamber which formed primarily from tholeiitic basalts; during the later capping-lava stage of Mauna Kea, alkalic basalts tore off chunks of these cumulates during ascent to the surface. We have measured several diffusion profiles in olivine xenocrysts from a single basalt sample. Because these xenocrysts have homogenous core compositions identical to a neighboring dunite cumulate, and because they are much larger and texturally distinct from compositionally dissimilar olivine phenocrysts, they are interpreted to be cumulate olivines which were dislodged during magma recharge/mixing in the stagnation zone. Although the orientations of the phenocrysts are not yet known, the diffusion profiles have been fit using diffusion coefficients parallel to the c and a crystallographic axes (i.e. minimum and maximum values). Modeling diffusion profiles yields ∫Ddt ≤4.5 x 10-5 cm2. Assuming that the xenocrysts were broken off from the cumulate immediately when the magma chamber was recharged, it is possible to calculate the maximum stagnation time of the basalts. Thus, the retrieved ∫Ddt value yields a maximum stagnation time of ~0.7 years. References: Fodor RV, Galar, PA (1997). A View into the Subsurface of Mauna Kea Volcano, Hawaii: Crystallization Processes Interpreted through the Petrology and Petrography of

Possible Origin of Stagnation and Variability of Earth's Biodiversity

Science.gov (United States)

Stollmeier, Frank; Geisel, Theo; Nagler, Jan

2014-06-01

The magnitude and variability of Earth's biodiversity have puzzled scientists ever since paleontologic fossil databases became available. We identify and study a model of interdependent species where both endogenous and exogenous impacts determine the nonstationary extinction dynamics. The framework provides an explanation for the qualitative difference of marine and continental biodiversity growth. In particular, the stagnation of marine biodiversity may result from a global transition from an imbalanced to a balanced state of the species dependency network. The predictions of our framework are in agreement with paleontologic databases.

Study of atmospheric stagnation, recirculation, and ventilation potential at Narora Atomic Power Station site

International Nuclear Information System (INIS)

Kumar, Deepak; Kumar, Avinash; Kumar, Vimal; Rao, K.S.; Kumar, Jaivender; Ravi, P.M.

2011-01-01

Atmosphere is an important pathway to be considered in assessment of the environmental impact of radioactivity releases from nuclear facilities. Estimation of concentration of released effluents in air and possible ground contamination needs an understanding of relevant atmospheric dispersion. This article describes the meteorological characteristics of Narora Atomic Power Station (NAPS) site by using the integral parameters developed by Allwine and Whiteman. Meteorological data measured during the period 2006-2010 were analyzed. The integral quantities related to the occurrence of stagnation, recirculation, and ventilation characteristics were studied for NAPS site to assess the dilution potential of the atmosphere. Wind run and recirculation factors were calculated for a 24-h transport time using 5 years of hourly surface measurements of wind speed and direction. The occurrence of stagnation, recirculation, and ventilation characteristics during 2006-2010 at NAPS site is observed to be 33.8% of the time, 19.5% of the time, and 34.7% of the time, respectively. The presence of strong winds with predominant wind direction NW and WNW during winter and summer seasons leads to higher ventilation (48.1% and 44.3%) and recirculation (32.6% of the summer season). The presence of light winds and more dispersed winds during prewinter season with predominant wind directions W and WNW results in more stagnation (59.7% of the prewinter season). Thus, this study will serve as an essential meteorological tool to understand the transport mechanism of atmospheric radioactive effluent releases from any nuclear industry. (author)

Overcoming Stagnation in the Levels and Distribution of Child Mortality: The Case of the Philippines.

Directory of Open Access Journals (Sweden)

Raoul Bermejo

Full Text Available Health-related within-country inequalities continue to be a matter of great interest and concern to both policy makers and researchers. This study aims to assess the level and the distribution of child mortality outcomes in the Philippines across geographical and socioeconomic indicators.Data on 159,130 children ever borne were analysed from five waves of the Philippine Demographic and Health Survey. Direct estimation was used to construct under-five and neonatal mortality rates for the period 1980-2013. Rate differences and ratios, and where possible, slope and relative indices of inequality were calculated to measure disparities on absolute and relative scales. Stratification was undertaken by levels of rural/urban location, island groups and household wealth.National under-five and neonatal mortality rates have shown considerable albeit differential reductions since 1980. Recently released data suggests that neonatal mortality has declined following a period of stagnation. Declines in under-five mortality have been accompanied by decreases in wealth and geography-related absolute inequalities. However, relative inequalities for the same markers have remained stable over time. For neonates, mixed evidence suggests that absolute and relative inequalities have remained stable or may have risen.In addition to continued reductions in under-five mortality, new data suggests that the Philippines have achieved success in addressing the commonly observed stagnated trend in neonatal mortality. This success has been driven by economic improvement since 2006 as well as efforts to implement a nationwide universal health care campaign. Yet, such patterns, nonetheless, accorded with persistent inequalities, particularly on a relative scale. A continued focus on addressing universal coverage, the influence of decentralisation and armed conflict, and issues along the continuum of care is advocated.

An experimental study on the influence of water stagnation and temperature change on water quality in a full-scale domestic drinking water system.

Science.gov (United States)

Zlatanović, Lj; van der Hoek, J P; Vreeburg, J H G

2017-10-15

The drinking water quality changes during the transport through distribution systems. Domestic drinking water systems (DDWSs), which include the plumbing between the water meter and consumer's taps, are the most critical points in which water quality may be affected. In distribution networks, the drinking water temperature and water residence time are regarded as indicators of the drinking water quality. This paper describes an experimental research on the influence of stagnation time and temperature change on drinking water quality in a full-scale DDWS. Two sets of stagnation experiments, during winter and summer months, with various stagnation intervals (up to 168 h of stagnation) were carried out. Water and biofilms were sampled at two different taps, a kitchen and a shower tap. Results from this study indicate that temperature and water stagnation affect both chemical and microbial quality in DDWSs, whereas microbial parameters in stagnant water appear to be driven by the temperature of fresh water. Biofilm formed in the shower pipe contained more total and intact cells than the kitchen pipe biofilm. Alphaproteobacteria were found to dominate in the shower biofilm (78% of all Proteobacteria), while in the kitchen tap biofilm Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria were evenly distributed. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Hall effect upon small wavelength kink instabilities near an elliptic magnetic stagnation line

International Nuclear Information System (INIS)

Spies, G.O.; Faghihi, M.

1985-12-01

To explore the question whether the Hall effect removes the unphysical feature of ideal magnetohydrodynamics of predicting unstable small wavelenght kinks near any elliptic magnetic stagnation line, a spectral analysis is performed of the motion of an incompressible plasma about cylindrical Z-pinch equilibria with circular sections. The eigenvalue loci in the complex frequency plane are derived for the equilibrium with constant current density. These show that every particular mode becomes stable as the Hall parameter exceeds a critical value. However, this critical value is a decreasing function of the ideal growth rate and has a pole at the origin, implying that there always remains an infinite reservoir of slowly growing instabilities. Correspondingly, for equilibiria with arbitrary current distributions, the stability criterion is unaffected by the Hall term. (author)

Achievement Goals and Achievement Emotions: Testing a Model of Their Joint Relations with Academic Performance

Science.gov (United States)

Pekrun, Reinhard; Elliot, Andrew J.; Maier, Markus A.

2009-01-01

The authors propose a theoretical model linking achievement goals and achievement emotions to academic performance. This model was tested in a prospective study with undergraduates (N = 213), using exam-specific assessments of both goals and emotions as predictors of exam performance in an introductory-level psychology course. The findings were…

Institutionel stagnation i hertugdømmet Slesvig 1840-1860

DEFF Research Database (Denmark)

Clausen, Thomas

2017-01-01

This article provides a study of the framework conditions for trade and industry in the Duchy of Schleswig in the middle of the 19th century. Grounded on theory of institutional economics the main argument of the paper is that Schleswig on a range of parameters suffered from stagnation...... in the development of the economy. The cause of this slowdown had to do with inertia in adaption of important institutional arrangement to the increasing complexity of trade and business. The study concludes that the Duchy, despite a seemingly favorable starting point, lost ground and that the institutional...

Effects of platinum stagnation surface on the lean extinction limits of premixed methane/air flames at moderate surface temperatures

Energy Technology Data Exchange (ETDEWEB)

Wiswall, J.T.; Li, J.; Wooldridge, M.S.; Im, H.G. [Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI (United States)

2011-01-15

A stagnation flow reactor was used to study the effects of platinum on the lean flammability limits of atmospheric pressure premixed methane/air flames at moderate stagnation surface temperatures. Experimental and computational methods were used to quantify the equivalence ratio at the lean extinction limit ({phi}{sub ext}) and the corresponding stagnation surface temperature (T{sub s}). A range of flow rates (57-90 cm/s) and corresponding strain rates were considered. The results indicate that the gas-phase methane/air flames are sufficiently strong relative to the heterogeneous chemistry for T{sub s} conditions less than 750 K that the platinum does not affect {phi}{sub ext}. The computational results are in good agreement with the experimentally observed trends and further indicate that higher reactant flow rates (>139 cm/s) and levels of dilution (>{proportional_to}10% N{sub 2}) are required to weaken the gas-phase flame sufficiently for surface reaction to play a positive role on extending the lean flammability limits. (author)

Detection of flow separation and stagnation points using artificial hair sensors

International Nuclear Information System (INIS)

Phillips, D M; Baur, J W; Ray, C W; Hagen, B J; Reich, G W; Su, W

2015-01-01

Recent interest in fly-by-feel approaches for aircraft control has motivated the development of novel sensors for use in aerial systems. Artificial hair sensors (AHSs) are one type of device that promise to fill a unique niche in the sensory suite for aerial systems. In this work, we investigate the capability of an AHS based on structural glass fibers to directly identify flow stagnation and separation points on a cylindrical domain in a steady flow. The glass fibers are functionalized with a radially aligned carbon nanotube (CNT) forest and elicit a piezoresistive response as the CNT forest impinges on electrodes in a micropore when the hair is deflected due to viscous drag forces. Particle image velocimetry is used to measure the flow field allowing for the resulting moment and force acting on the hair to be correlated with the electrical response. It is demonstrated that the AHS provides estimates for the locations of both the stagnation and separation in steady flow. From this, a simulation of a heading estimation is presented to demonstrate a potential application for hair sensors. These results motivate the construction of large arrays of hair sensors for imaging and resolving flow structures in real time. (paper)

Using 1D theory to understand 3D stagnation of a wire-array Z pinch in the absence of radiation

Science.gov (United States)

Yu, Edmund

2015-11-01

Many high-energy-density systems implode towards the axis of symmetry, where it collides on itself, forming a hot plasma. However, experiments show these imploding plasmas develop three-dimensional (3D) structures. As a result, the plasma cannot completely dissipate its kinetic energy at stagnation, instead retaining significant 3D flow. A useful tool for understanding the effects of this residual flow is 3D simulation, but the amount and complexity of information can be daunting. To address this problem, we explore the connection between 3D simulation and one-dimensional (1D) theory. Such a connection, if it exists, is mutually beneficial: 1D theory can provide a clear picture of the underlying dynamics of 3D stagnation. On the other hand, deviations between theory and simulation suggest how 1D theory must be modified to account for 3D effects. In this work, we focus on a 3D, magnetohydrodynamic simulation of a compact wire-array Z pinch. To provide a simpler background against which to test our ideas, we artificially turn off radiation during the stagnation phase. Examination of the initial accumulation of mass on axis reveals oblique collision between jets, shock accretion, and vortex formation. Despite evidence for shock-dominated stagnation, a 1D shockless stagnation solution is more appropriate for describing the global dynamics, in that it reproduces the increase of on-axis density with time. However, the 1D solution must be modified to account for 3D effects: the flows suggest enhanced thermal transport as well as centrifugal force. Upon reaching peak compression, the stagnation transitions to a second phase, in which the high-pressure core on axis expands outward into the remaining imploding plasma. During this phase, a 1D shock solution describes the growth of the shock accretion region, as well as the decrease of on-axis density with time. However, the effect of 3D flows is still present: the on-axis temperature does not cool during expansion, which

Thermophysical analysis for three-dimensional MHD stagnation-point flow of nano-material influenced by an exponential stretching surface

Directory of Open Access Journals (Sweden)

Fiaz Ur Rehman

2018-03-01

Full Text Available In the present paper a theoretical investigation is performed to analyze heat and mass transport enhancement of water-based nanofluid for three dimensional (3D MHD stagnation-point flow caused by an exponentially stretched surface. Water is considered as a base fluid. There are three (3 types of nanoparticles considered in this study namely, CuO (Copper oxide, Fe3O4 (Magnetite, and Al2O3 (Alumina are considered along with water. In this problem we invoked the boundary layer phenomena and suitable similarity transformation, as a result our three dimensional non-linear equations of describing current problem are transmuted into nonlinear and non-homogeneous differential equations involving ordinary derivatives. We solved the final equations by applying homotopy analysis technique. Influential outcomes of aggressing parameters involved in this study, effecting profiles of temperature field and velocity are explained in detail. Graphical results of involved parameters appearing in considered nanofluid are presented separately. It is worth mentioning that Skin-friction along x and y-direction is maximum for Copper oxide-water nanofluid and minimum for Alumina-water nanofluid. Result for local Nusselt number is maximum for Copper oxide-water nanofluid and is minimum for magnetite-water nanofluid. Keywords: Heat transfer, Nanofluids, Stagnation-point flow, Three-dimensional flow, Nano particles, Boundary layer

Orality disorders in melancholia: acedia as stagnation

Directory of Open Access Journals (Sweden)

Ana Cecília Magtaz

2012-09-01

Full Text Available In this article valuable contributions by Lasègue, Freud and Abraham are discussed, as they are all indispensible to the understanding of orality disorders in melancholia. Although none of the above authors used the exact term "orality disorders," their understandings of both hysteria and melancholia are important in the debate surrounding the clinical treatment of these difficulties. Sadness is a common denominator for the authors, but contributions on acedia, the "noonday demon" mentioned by Agamben, are also important. Acedia is defined as stagnation, a desperate lack of vigor when faced with a wearying and demanding situation. Those who suffer from chronic acedia feel great inertia and are unable to envision a future. They see their creativity wane away, especially due to the painful isolation caused by what might be called anguished sadness - a denial of sadness through manic action.

Classroom Environment, Achievement Goals and Maths Performance: Gender Differences

Science.gov (United States)

Gherasim, Loredana Ruxandra; Butnaru, Simona; Mairean, Cornelia

2013-01-01

This study investigated how gender shapes the relationships between classroom environment, achievement goals and maths performance. Seventh-grade students ("N"?=?498) from five urban secondary schools filled in achievement goal orientations and classroom environment scales at the beginning of the second semester. Maths performance was…

Achievement goals, self-handicapping, and performance: a 2 x 2 achievement goal perspective.

Science.gov (United States)

Ntoumanis, Nikos; Thøgersen-Ntoumani, Cecilie; Smith, Alison L

2009-11-01

Elliot and colleagues (2006) examined the effects of experimentally induced achievement goals, proposed by the trichotomous model, on self-handicapping and performance in physical education. Our study replicated and extended the work of Elliot et al. by experimentally promoting all four goals proposed by the 2 x 2 model (Elliot & McGregor, 2001), measuring the participants' own situational achievement goals, using a relatively novel task, and testing the participants in a group setting. We used a randomized experimental design with four conditions that aimed to induce one of the four goals advanced by the 2 x 2 model. The participants (n = 138) were undergraduates who engaged in a dart-throwing task. The results pertaining to self-handicapping partly replicated Elliot and colleagues' findings by showing that experimentally promoted performance-avoidance goals resulted in less practice. In contrast, the promotion of mastery-avoidance goals did not result in less practice compared with either of the approach goals. Dart-throwing performance did not differ among the four goal conditions. Personal achievement goals did not moderate the effects of experimentally induced goals on self-handicapping and performance. The extent to which mastery-avoidance goals are maladaptive is discussed, as well as the interplay between personal and experimentally induced goals.

Pressure and temperature development in solar heating system during stagnation

DEFF Research Database (Denmark)

Dragsted, Janne; Furbo, Simon; Chen, Ziqian

2010-01-01

of the pipes of the solar collector loop. During the investigation the pre-pressure of the expansion vessel and system filling pressure was changed. The investigations showed that a large pressurised expansion vessel will protect the collector loop from critically high temperatures as long as the solar......This paper presents an investigation of stagnation in solar collectors and the effects it will have on the collector loop. At a laboratory test stand at the Technical University of Denmark, a pressurized solar collector loop was designed to test different numbers of collectors and different designs...

Dynamic and Stagnating Plasma Flow Leading to Magnetic-Flux-Tube Collimation

International Nuclear Information System (INIS)

You, S.; Yun, G.S.; Bellan, P.M.

2005-01-01

Highly collimated, plasma-filled magnetic-flux tubes are frequently observed on galactic, stellar, and laboratory scales. We propose that a single, universal magnetohydrodynamic pumping process explains why such collimated, plasma-filled magnetic-flux tubes are ubiquitous. Experimental evidence from carefully diagnosed laboratory simulations of astrophysical jets confirms this assertion and is reported here. The magnetohydrodynamic process pumps plasma into a magnetic-flux tube and the stagnation of the resulting flow causes this flux tube to become collimated

Impeding hohlraum plasma stagnation in inertial-confinement fusion.

Science.gov (United States)

Li, C K; Séguin, F H; Frenje, J A; Rosenberg, M J; Rinderknecht, H G; Zylstra, A B; Petrasso, R D; Amendt, P A; Landen, O L; Mackinnon, A J; Town, R P J; Wilks, S C; Betti, R; Meyerhofer, D D; Soures, J M; Hund, J; Kilkenny, J D; Nikroo, A

2012-01-13

This Letter reports the first time-gated proton radiography of the spatial structure and temporal evolution of how the fill gas compresses the wall blowoff, inhibits plasma jet formation, and impedes plasma stagnation in the hohlraum interior. The potential roles of spontaneously generated electric and magnetic fields in the hohlraum dynamics and capsule implosion are discussed. It is shown that interpenetration of the two materials could result from the classical Rayleigh-Taylor instability occurring as the lighter, decelerating ionized fill gas pushes against the heavier, expanding gold wall blowoff. This experiment showed new observations of the effects of the fill gas on x-ray driven implosions, and an improved understanding of these results could impact the ongoing ignition experiments at the National Ignition Facility.

The stagnation of the Mexican male life expectancy in the first decade of the 21st century

DEFF Research Database (Denmark)

Canudas-Romo, Vladimir; García-Guerrero, Víctor Manuel; Echarri-Cánovas, Carlos Javier

2015-01-01

OBJECTIVES: In the first decade of the 21st century, the Mexican life expectancy changed from a long trend of increase to stagnation. These changes concur with an increase in deaths by homicides that the country experienced in that decade, and an obesity epidemic that had developed over the last...... of life expectancy from 2000 to 2010. RESULTS: The apparent stagnation in life expectancy is the result of an increase in deaths by homicides and diabetes mellitus on the one hand, and the positive improvements observed in other causes of death on the other. The negative impact of homicides...... by 2 years if deaths by homicides and diabetes mellitus had been avoided....

Numerical analysis for MHD thermal and solutal stratified stagnation point flow of Powell-Eyring fluid induced by cylindrical surface with dual convection and heat generation effects

Science.gov (United States)

Khalil-Ur-Rehman; Malik, M. Y.; Bilal, S.; Bibi, M.

The current analysis reports the untapped characteristics of magneto-hydrodynamic dual convection boundary layer stagnation point flow of Powell-Eyring fluid by way of cylindrical surface. Flow exploration is carried out with the combined effects of thermal and solutal stratification. The strength of temperature and concentration adjacent to the cylindrical surface is assumed to be greater than the ambient fluid. Flow conducting mathematically modelled equations are fairly transformed into system of coupled non-linear ordinary differential equations with the aid of suitable transformations. The computations are made against these resultant coupled equations through shooting technique by the support of fifth order Runge-Kutta algorithm. A parametric study is performed to examine the effect logs of various pertinent flow controlling parameters on the velocity, temperature and concentration flow regime. The achieved outcomes are validated by developing comparison with existing published literature. In addition, numerical values of skin friction coefficient and Nusselt number are presented graphically for two different geometries namely, plate and cylinder.

Studies on scaling of flow noise received at the stagnation point of an axisymmetric body

Science.gov (United States)

Arakeri, V. H.; Satyanarayana, S. G.; Mani, K.; Sharma, S. D.

1991-05-01

A description of the studies related to the problem of scaling of flow noise received at the stagnation point of axisymmetric bodies is provided. The source of flow noise under consideration is the transitional/turbulent regions of the boundary layer flow on the axisymmetric body. Lauchle has recently shown that the noise measured in the laminar region (including the stagnation point) corresponds closely to the noise measured in the transition region, provided that the acoustic losses due to diffraction are accounted for. The present study includes experimental measurement of flow noise at the stagnation point of three different shaped axisymmetric headforms. One of the body shapes chosen is that used by Lauchle in similar studies. This was done to establish the effect of body size on flow noise. The results of the experimental investigations clearly show that the flow noise received at the stagnation point is a strong function of free stream velocity, a moderately strong function of body scale but a weak function of boundary layer thickness. In addition, there is evidence that when body scale change is involved, flow noise amplitude scales but no frequency shift is involved. A scaling procedure is proposed based on the present observations along with those of Lauchle. At a given frequency, the amplitude of noise level obtained under model testing conditions is first scaled to account for differences in the velocity and size corresponding to the prototype conditions; then a correction to this is applied to account for losses due to diffraction, which are estimated on the basis of the geometric theory of diffraction (GTD) with the source being located at the predicted position of turbulent transition. Use of the proposed scaling law to extrapolate presently obtained noise levels to two other conditions involving larger-scale bodies show good agreement with actually measured levels, in particular at higher frequencies. Since model scale results have been used

On two special values of temperature factor in hypersonic flow stagnation point

Science.gov (United States)

Bilchenko, G. G.; Bilchenko, N. G.

2018-03-01

The hypersonic aircraft permeable cylindrical and spherical surfaces laminar boundary layer heat and mass transfer control mathematical model properties are investigated. The nonlinear algebraic equations systems are obtained for two special values of temperature factor in the hypersonic flow stagnation point. The mappings bijectivity between heat and mass transfer local parameters and controls is established. The computation experiments results are presented: the domains of allowed values “heat-friction” are obtained.

A meta-analysis of self-reported achievement goals and nonself-report performance across three achievement domains (work, sports, and education.

Directory of Open Access Journals (Sweden)

Nico W Van Yperen

Full Text Available During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that - overall - approach goals (either mastery or performance were associated positively with performance attainment, whereas avoidance goals (either mastery or performance were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of

A meta-analysis of self-reported achievement goals and nonself-report performance across three achievement domains (work, sports, and education).

Science.gov (United States)

Van Yperen, Nico W; Blaga, Monica; Postmes, Tom

2014-01-01

During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that - overall - approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of performance

International health policy and stagnating maternal mortality: is there a causal link?

Science.gov (United States)

Unger, Jean-Pierre; Van Dessel, Patrick; Sen, Kasturi; De Paepe, Pierre

2009-05-01

This paper examines why progress towards Millennium Development Goal 5 on maternal health appears to have stagnated in much of the global south. We contend that besides the widely recognised existence of weak health systems, including weak services, low staffing levels, managerial weaknesses, and lack of infrastructure and information, this stagnation relates to the inability of most countries to meet two essential conditions: to develop access to publicly funded, comprehensive health care, and to provide the not-for-profit sector with needed political, technical and financial support. This paper offers a critical perspective on the past 15 years of international health policies as a possible cofactor of high maternal mortality, because of their emphasis on disease control in public health services at the expense of access to comprehensive health care, and failures of contracting out and public-private partnerships in health care. Health care delivery cannot be an issue both of trade and of right. Without policies to make health systems in the global south more publicly-oriented and accountable, the current standards of maternal and child health care are likely to remain poor, and maternal deaths will continue to affect women and their families at an intolerably high level.

Unsteady MHD stagnation flow over a moving wall

International Nuclear Information System (INIS)

Kumari, M.; Nath, G.

2006-01-01

The unsteady viscous stagnation flow of an electrically conducting fluid over a continuously moving wall with an applied magnetic field has been investigated when the free stream and wall velocities increase arbitrarily with time. The flow is initially (t = 0) steady and at time t > 0, it becomes unsteady. The semi-similar solution of the unsteady Navier-Stokes equations along with the energy equation governing the flow and heat transfer has been obtained numerically. Also the self-similar solution is obtained when the surface and free stream velocities vary inversely as a linear function of time. The shear stress and the heat transfer increase with time and magnetic field. The surface shear stress vanishes for certain value of the ratio of the wall velocity to the free stream velocity. (author)

Avoiding Intellectual Stagnation: The Starship as an Expander of Minds

Science.gov (United States)

Crawford, Ian A.

2014-06-01

Interstellar exploration will advance human knowledge and culture in multiple ways. Scientifically, it will advance our understanding of the interstellar medium, stellar astrophysics, planetary science and astrobiology. In addition, significant societal and cultural benefits will result from a programme of interstellar exploration and colonisation. Most important will be the cultural stimuli resulting from expanding the horizons of human experience, and increased opportunities for the spread and diversification of life and culture through the Galaxy. Ultimately, a programme of interstellar exploration may be the only way for human (and post-human) societies to avoid the intellectual stagnation predicted for the `end of history'.

New optical method for heat flux measurements in stagnation point laminar methane/air flames and hydrogen/methane/air flames using thermographic phosphors

Energy Technology Data Exchange (ETDEWEB)

Elmnefi, Mohamed Salem

2010-11-24

In the present study, a new optical method was implemented to study the heat transfer from flat stagnation point flames which can be regarded as one-dimensional in the central part. Premixed methane-air flames and hydrogen-methane-air flames were investigated. The effects of burner-to-plate distance and the fresh gas mixture velocity on heat transfer were examined. Experiments were performed using light induced phosphorescence from thermographic phosphors to study the wall temperatures and heat fluxes of nearly one-dimensional flat premixed flames impinging upward normally on a horizontal water cooled circular flat plate. The investigated flames were stoichiometric, lean and rich laminar methane/air flames with different equivalence ratios of {phi} =1, {phi} = 0.75 and {phi} = 1.25 and stoichiometric laminar hydrogen/methane/air flames. Mixtures of air with 10, 25, 50 and 75 % hydrogen in methane (CH{sub 4}) as well as a pure hydrogen flames at ambient pressure were investigated. The central part of this plate was an alumina ceramic plate coated from both sides with chromium doped alumina (ruby) and excited with a Nd:YAG laser or a green light emitting diode (LED) array to measure the wall temperature from both sides and thus the heat flux rate from the flame. The outlet velocity of the gases was varied from 0.1 m/s to 1.2 m/s. The burner to plate distance ranged from 0.5 to 2 times the burner exit diameter (d = 30 mm).The accuracy of the method was evaluated. The measured heat flux indicate the change of the flame stabilization mechanism from a burner stabilized to a stagnation plate stabilized flame. The results were compared to modeling results of a one dimensional stagnation point flow, with a detailed reaction mechanism. In order to prove the model, also measured gas phase temperatures by OH LIF for a stoichiometric stagnation point flame were discussed. It turns out that the flame stabilization mechanism and with it the heat fluxes change from low to high

Numerical modeling of time-dependent bio-convective stagnation flow of a nanofluid in slip regime

Directory of Open Access Journals (Sweden)

Rakesh Kumar

Full Text Available A numerical investigation of unsteady stagnation point flow of bioconvective nanofluid due to an exponential deforming surface is made in this research. The effects of Brownian diffusion, thermophoresis, slip velocity and thermal jump are incorporated in the nanofluid model. By utilizing similarity transformations, the highly nonlinear partial differential equations governing present nano-bioconvective boundary layer phenomenon are reduced into ordinary differential system. The resultant expressions are solved for numerical solution by employing a well-known implicit finite difference approach termed as Keller-box method (KBM. The influence of involved parameters (unsteadiness, bioconvection Schmidt number, velocity slip, thermal jump, thermophoresis, Schmidt number, Brownian motion, bioconvection Peclet number on the distributions of velocity, temperature, nanoparticle and motile microorganisms concentrations, the coefficient of local skin-friction, rate of heat transport, Sherwood number and local density motile microorganisms are exhibited through graphs and tables. Keywords: Unsteadiness, Bio-convection, Slip regime, Stagnation point flow, Numerical modeling

Stagnation of the exploitation of Al ores and the depression of world prices of Al

Directory of Open Access Journals (Sweden)

Slavkovský Jozef

1999-03-01

Full Text Available In the contribution, data on Al – a metal of the 20th century are compiled together with the problems of genesis of the Al mineral raw ma-terials as well as types of bauxite and Al-laterite deposits. Furthermore, an overview of the world exploitation of bauxite during 1935-1980 is given along with the prognoses to 2000 and present situation (1992-1996. Overviews of the production of Al follows, providing its rela-tion to the bauxite exploitation. Contrary to the prognoses, a stabilization or stagnation has been observed in the exploitation of bauxite and production of Al during nineties, which a tendency is directly reflected in the world price of this commodity. When analyzing the Al prices for a longer period, some serious deviations can be noticed, that however presently represent a long-term minimum. We hope the stagnation of the production and the price decline are only temporary and new possibilities of the utilization of Al will be found soon.

Impacts of Anthropogenic Aerosols on Regional Climate: Extreme Events, Stagnation, and the United States Warming Hole

Science.gov (United States)

Mascioli, Nora R.

temperature response pattern in AER and GHG is characterized by strong responses over the western U.S. and weak or opposite signed responses over the southeast U.S., raising the question of whether the observed U.S. "warming hole" could have a forced component. To address this question, I systematically examine observed seasonal temperature trends over all time periods of at least 10 years during 1901-2015. In the northeast and southern U.S., significant summertime cooling occurs from the early 1950s to the mid 1970s, which I partially attribute to increasing anthropogenic aerosol emissions (median fraction of the observed temperature trends explained is 0.69 and 0.17, respectively). In winter, the northeast and southern U.S. cool significantly from the early 1950s to the early 1990s, which I attribute to long-term phase changes in the North Atlantic Oscillation and the Pacific Decadal Oscillation. Rather than being a single phenomenon stemming from a single cause, both the warming hole and its dominant drivers vary by season, region, and time period. Finally, I examine historical and projected future changes in atmospheric stagnation. Stagnation, which is characterized by weak winds and an absence of precipitation, is a meteorological contributor to heat waves, extreme pollution, and drought. Using CM3, I show that regional stagnation trends over the historical period (1860-2005) are driven by changes in anthropogenic aerosol emissions, rather than rising greenhouse gases. In the northeastern and central United States, aerosol-induced changes in surface and upper level winds produce significant decreases in the number of stagnant summer days, while decreasing precipitation in the southeast US increases the number of stagnant summer days. Outside of the U.S., significant drying over eastern China in response to rising aerosol emissions contributed to increased stagnation during 1860-2005. Additionally, this region was found to be particularly sensitive to changes in local

Assessment of Fuel Analysis Methodology and Fission Product Release for 37-Element Fuel by Using the Latest IST Codes during Stagnation Feeder Break in CANDU

International Nuclear Information System (INIS)

Park, Joo Hwan; Jung, Jong Yeob

2009-09-01

Feeder break accident is regarded as one of the design basis accident in CANDU reactor which results in a fuel failure. For a particular range of inlet feeder break sizes, the flow in the channel is reduced sufficiently that the fuel and fuel channel integrity can be significantly affected to have damage in the affected channel, while the remainder of the core remains adequately cooled. The flow in the downstream channel can be more or less stagnated due to a balance between pressure at the break on the upstream side and the reverse driving pressure between the break and the downstream end. In the extreme, this can lead to rapid fuel heatup and fuel damage and failure of the fuel channel similar to that associated with a severe channel flow blockage. Such an inlet feeder break scenario is called a stagnation break. In this report, the fuel analysis methodology and the assessment results of fission product inventory and release during the stagnation feeder break are described for conservatively assumed limiting channel. The accident was assumed to be occurred in the refurbished Wolsong unit 1 and the latest safety codes were used in the analysis. Fission product inventories during the steady state were calculated by using ELESTRES-IST 1.2 code. The whole analysis process was carried out by a script file which was programmed by Perl language. The perl script file was programmed to make all ELESTRES input files for each bundle and each ring based on the given power-burnup history and thermal-hydraulic conditions of the limiting channel and to perform the fuel analysis automatically. The fission product release during the transient period of stagnation feeder break was evaluated by applying Gehl model. The amounts of each isotope's release are conservatively evaluated for additional 2 seconds after channel failure. The calculated fission product releases are provided to the following dose assessment as a source term

A Model of Statistics Performance Based on Achievement Goal Theory.

Science.gov (United States)

Bandalos, Deborah L.; Finney, Sara J.; Geske, Jenenne A.

2003-01-01

Tests a model of statistics performance based on achievement goal theory. Both learning and performance goals affected achievement indirectly through study strategies, self-efficacy, and test anxiety. Implications of these findings for teaching and learning statistics are discussed. (Contains 47 references, 3 tables, 3 figures, and 1 appendix.)…

Stagnations of increasing trends in negative pressure with repeated cavitation in water/metal Berthelot tubes as a result of mechanical sealing

International Nuclear Information System (INIS)

Hiro, Kazuki; Ohde, Yoshihito; Tanzawa, Yasutoshi

2003-01-01

To investigate effects of mechanical sealing on negative pressures in water/metal tube Berthelot systems, trends in negative pressure are observed through runs of temperature cycles below 90 deg. C in two systems made of metals having small amounts of gas inclusions. The first system is a pre-degassed all-stainless-steel tube/plug system. The steel is a special product for vacuum engineering. The second is the same tube sealed with plugs made of silver solidified one-dimensionally in a vacuum furnace. A new type of trend, stagnation for intermediate cycles is found in both systems so long as sealing distortion of each plug is small in amount. The stagnation period for the first system is longer than that for the second one. A metallurgical mechanism of a gas-being-replenished crevice model is proposed: distorted parts of metals undergo heat-treatment during runs of temperature cycles, and the heat-treatment enhances the rates of impurity gas transports to crevices on the metal surface where cavitation occurs, and the transport causes the stagnation for cycles during which the rates are still high

Expansionary economic effects of energy conversion under stagnation

International Nuclear Information System (INIS)

Ono, Yoshiyasu

2013-01-01

After the Fukushima disaster, energy conversion such as nuclear power phaseout and deployment of renewable energy or survival of nuclear power had been actively argued pro and con. Both sides admitted extra costs were needed but their economic effects would be contrary dependent on business state. Under better economy, extra costs would be actual burden of total economy. Under stagnation as was long in Japan at present, extra costs brought about expansion of employment and economy with simulated consumption increase. Industry conversion would occur such industry intensively using power would depreciate and energy conserved industry would grow. Difference of power use intensity between industries made difficult in energy conversion because present Japanese industry constitution was mostly formed based on cheap power cost for industry use. Even taking account of international competition, the same would be true by adjusting finance balance sheet and currency exchange rate. (T. Tanaka)

Nonlinear radiative heat transfer to stagnation-point flow of Sisko fluid past a stretching cylinder

Energy Technology Data Exchange (ETDEWEB)

Khan, Masood [Department of Mathematics, Quaid-i-Azam University, Islamabad 44000 (Pakistan); Malik, Rabia, E-mail: rabiamalik.qau@gmail.com [Department of Mathematics, Quaid-i-Azam University, Islamabad 44000 (Pakistan); Department of Mathematics and Statistics, International Islamic University Islamabad 44000 (Pakistan); Hussain, M. [Department of Sciences and Humanities, National University of Computer and Emerging Sciences, Islamabad 44000 (Pakistan)

2016-05-15

In the present paper, we endeavor to perform a numerical analysis in connection with the nonlinear radiative stagnation-point flow and heat transfer to Sisko fluid past a stretching cylinder in the presence of convective boundary conditions. The influence of thermal radiation using nonlinear Rosseland approximation is explored. The numerical solutions of transformed governing equations are calculated through forth order Runge-Kutta method using shooting technique. With the help of graphs and tables, the influence of non-dimensional parameters on velocity and temperature along with the local skin friction and Nusselt number is discussed. The results reveal that the temperature increases however, heat transfer from the surface of cylinder decreases with the increasing values of thermal radiation and temperature ratio parameters. Moreover, the authenticity of numerical solutions is validated by finding their good agreement with the HAM solutions.

Nonlinear radiative heat transfer to stagnation-point flow of Sisko fluid past a stretching cylinder

Directory of Open Access Journals (Sweden)

Masood Khan

2016-05-01

Full Text Available In the present paper, we endeavor to perform a numerical analysis in connection with the nonlinear radiative stagnation-point flow and heat transfer to Sisko fluid past a stretching cylinder in the presence of convective boundary conditions. The influence of thermal radiation using nonlinear Rosseland approximation is explored. The numerical solutions of transformed governing equations are calculated through forth order Runge-Kutta method using shooting technique. With the help of graphs and tables, the influence of non-dimensional parameters on velocity and temperature along with the local skin friction and Nusselt number is discussed. The results reveal that the temperature increases however, heat transfer from the surface of cylinder decreases with the increasing values of thermal radiation and temperature ratio parameters. Moreover, the authenticity of numerical solutions is validated by finding their good agreement with the HAM solutions.

Characteristics of buoyancy force on stagnation point flow with magneto-nanoparticles and zero mass flux condition

Directory of Open Access Journals (Sweden)

Iftikhar Uddin

2018-03-01

Full Text Available This attempt dedicated to the solution of buoyancy effect over a stretching sheet in existence of MHD stagnation point flow with convective boundary conditions. Thermophoresis and Brownian motion aspects are included. Incompressible fluid is electrically conducted in the presence of varying magnetic field. Boundary layer analysis is used to develop the mathematical formulation. Zero mass flux condition is considered at the boundary. Non-linear ordinary differential system of equations is constructed by means of proper transformations. Interval of convergence via numerical data and plots are developed. Characteristics of involved variables on the velocity, temperature and concentration distributions are sketched and discussed. Features of correlated parameters on Cf and Nu are examined by means of tables. It is found that buoyancy ratio and magnetic parameters increase and reduce the velocity field. Further opposite feature is noticed for higher values of thermophoresis and Brownian motion parameters on concentration distribution. Keywords: Stagnation point, MHD, Nanoparticles, Zero mass flux condition

Local similar solution of MHD stagnation point flow in Carreau fluid over a non-linear stretched surface with double stratified medium

Directory of Open Access Journals (Sweden)

M. Farooq

Full Text Available This article studies MHD double stratified stagnation point flow of Carreau fluid towards a non linear stretchable surface with radiation. Features of heat and mass transfer are evaluated by using convective boundary conditions. Resulting nonlinear problems are solved and studied for the velocity, temperature and concentration fields. Heat and mass transfer rates in addition to skin friction are discussed. Besides this for the verification of the present findings, the results of presented analysis have been compared with the available works in particular situations and reasonable agreement is noted. Keywords: Convective boundary condition, Thermal radiation, Double stratification, Stagnation point flow

Extending hierarchical achievement motivation models: the role of motivational needs for achievement goals and academic performance

NARCIS (Netherlands)

Bipp, T.; Dam, van K.

2014-01-01

In the current study, we investigated the role of three basic motivational needs (need for power, affiliation, achievement) as antecedents of goals within the 2 × 2 achievement goal framework, and examined their combined predictive validity with regard to academic performance in a sample of 120

New Stagnation Arc Jet Model Design for Testing ADEPT 3-D Carbon Cloth

Science.gov (United States)

Beck, R.; Chen, Y.-K.; Wercinski, P.; Agrawal, P.; Chavez-Garcia, J.

2017-01-01

The ADEPT concept has been considered as an entry, descent and landing system to enable Human Mars class missions. Ground rules for the Mars studies required aerocapture, orbit, and then entry. The design utilizes a 3-D woven carbon cloth fabric as both heatshield and primary structure and design guidelines required 6 layers remaining after all entry events. The peak heating predicted for the ADEPT carbon cloth was 35 Wcm2 and resulting temperatures were predicted to be 1400K. Predictions for carbon mass loss were performed using equilibrium thermochemistry, which is only accurate for T2000K. Carbon oxidation is kinetically controlled at T2000K, and mass loss drops off considerably from equilibrium values. Design of the cloth thickness and mass would be significantly reduced if kinetics were considered. This effort was to design a stagnation test article design that could be used in the AHF with varying levels of oxygen where the results could be used to develop an engineering model to describe the recession rate of the carbon as a function of the partial pressure of monotomic oxygen.

Componential Analysis of Analogical-Reasoning Performance of High and Low Achievers.

Science.gov (United States)

Armour-Thomas, Eleanor; Allen, Brenda A.

1990-01-01

Assessed analogical reasoning in high- and low-achieving students at the high school level and determined whether analogical reasoning was related to academic achievement in ninth grade students (N=54). Results indicated that high achievers performed better than low achievers on all types of analogical-reasoning processes. (Author/ABL)

Rise, stagnation, and rise of Danish women's life expectancy

DEFF Research Database (Denmark)

Lindahl-Jacobsen, Rune; Rau, Roland; Jeune, Bernard

2016-01-01

Health conditions change from year to year, with a general tendency in many countries for improvement. These conditions also change from one birth cohort to another: some generations suffer more adverse events in childhood, smoke more heavily, eat poorer diets, etc., than generations born earlier...... favor forecasts that hinge on cohort differences. We use a combination of age decomposition and exchange of survival probabilities between countries to study the remarkable recent history of female life expectancy in Denmark, a saga of rising, stagnating, and now again rising lifespans. The gap between...... female life expectancy in Denmark vs. Sweden grew to 3.5 y in the period 1975-2000. When we assumed that Danish women born 1915-1945 had the same survival probabilities as Swedish women, the gap remained small and roughly constant. Hence, the lower Danish life expectancy is caused by these cohorts...

The influence of the stagnation zone on the fluid dynamics at the nozzle exit of a confined and submerged impinging jet

Science.gov (United States)

Jeffers, Nicholas; Stafford, Jason; Conway, Ciaran; Punch, Jeff; Walsh, Edmond

2016-02-01

Low profile impinging jets provide a means to achieve high heat transfer coefficients while occupying a small quantity of space. Consequently, they are found in many engineering applications such as electronics cooling, annealing of metals, food processing, and others. This paper investigates the influence of the stagnation zone fluid dynamics on the nozzle exit flow condition of a low profile, submerged, and confined impinging water jet. The jet was geometrically constrained to a round, 16-mm diameter, square-edged nozzle at a jet exit to target surface spacing ( H/ D) that varied between 0.25 choice of inlet boundary conditions in numerical models, and it was found that it is necessary to model a jet tube length {{ L}{/}{ D}} > 0.5—where D is the inner diameter of the jet—in order to minimise modelling uncertainty.

Economics of thinning stagnated ponderosa pine sapling stands in the pine-grass areas of central Washington.

Science.gov (United States)

Robert W. Sassaman; James W. Barrett; Justin G. Smith

1972-01-01

Present net worth values earned by investments in precommercial thinning of stagnated ponderosa pine sapling stands are reported for three stocking levels. Thirteen timber management regimes are ranked by their returns from timber only, and 22 regimes are ranked according to their returns from timber and forage, with and without the allowable cut effect.

Metrics help rural hospitals achieve world-class performance.

Science.gov (United States)

Goodspeed, Scott W

2006-01-01

This article describes the emerging trend of using metrics in rural hospitals to achieve world-class performance. This trend is a response to the fact that rural hospitals have small patient volumes yet must maintain a profit margin in order to fulfill their mission to the community. The conceptual idea for this article is based largely on Robert Kaplan and David Norton's Balanced Scorecard articles in the Harvard Business Review. The ideas also come from the experiences of the 60-plus rural hospitals that are using the Balanced Scorecard and their implementation of metrics to influence performance and behavior. It is indeed possible for rural hospitals to meet and exceed the unique needs of patients and physicians (customers), to achieve healthy profit margins, and to be the rural hospital of choice that employees are proud to work for.

A Meta-Analysis of Self-Reported Achievement Goals and Nonself-Report Performance across Three Achievement Domains (Work, Sports, and Education)

NARCIS (Netherlands)

Van Yperen, Nico W.; Blaga, Monica; Postmes, Tom

2014-01-01

During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement

Holistic Performance Measurement to Achieve Sustainable Competitive Advantage

OpenAIRE

Keni Keni

2013-01-01

In the past, companies used balanced scorecard to measure its performance. Now, balanced scorecard as a performance measurement tool is no longer sufficient because business has been affected by changes to the natural environment and developing social expectations. In order to achieve sustainable competitive advantage, companies are beginning to address the risks and opportunities associated with these changes in their longer-term business planning. To turn risks into opportunities, companies...

Slab Penetration vs. Slab Stagnation: Mantle Reflectors as an Indicator

Science.gov (United States)

Okeler, A.; Gu, Y. J.; Schultz, R.; Contenti, S. M.

2011-12-01

Subducting oceanic lithosphere along convergent margins may stagnate near the base of the upper mantle or penetrate into the lower mantle. These dynamic processes cause extensive thermal and compositional variations, which can be observed in terms of impedance contrast (reflectivity) and topography of mantle transition zone (MTZ) discontinuities, i.e., 410- and 660-km discontinuities. In this study, we utilize ~ 15000 surface-reflected shear waves (SS) and their precursory arrivals (S410S and S660S) to analyze subduction related deformations on mantle reflectivity structure. We apply pre-stack, time-to-depth migration technique to SS precursors, and move weak underside reflections using PREM-predicted travel-time curves. Common Mid-point gathers are formed to investigate structure under the western Pacific, south America, and Mediterranean convergent boundaries. In general, mantle reflectivity structures are consistent with previous seismic tomography models. In regions of slab penetration (e.g., southern Kurile arc, Aegean Sea), our results show 1) a substantial decrease in S660S amplitude, and 2) strong lower mantle reflector(s) at ~ 900 km depth. These reflective structures are supported by zones of high P and S velocities extending into the lower mantle. Our 1-D synthetic simulations suggest that the decreasing S660S amplitudes are, at least partially, associated with shear wave defocusing due to changes in reflector depth (by ±20 km) within averaging bin. Assuming a ~500 km wide averaging area, a dipping reflector with 6-8 % slope can reduce the amplitude of a SS precursor by ~50%. On the other hand, broad depressions with strong impedance contrast at the base of the MTZ characterize the regions of slab stagnation, such as beneath the Tyrrhenian Sea and northeastern China. For the latter region, substantial topography on the 660-km discontinuity west of the Wadati-Benioff zone suggests that the stagnant part of the Pacific plate across Honshu arc is not

On the freestream matching condition for stagnation point turbulent flows

Science.gov (United States)

Speziale, C. G.

1989-01-01

The problem of plane stagnation point flow with freestream turbulence is examined from a basic theoretical standpoint. It is argued that the singularity which arises from the standard kappa-epsilon model is not due to a defect in the model but results from the use of an inconsistent freestream boundary condition. The inconsistency lies in the implementation of a production equals dissipation equilibrium hypothesis in conjunction with a freestream mean velocity field that corresponds to homogeneous plane strain - a turbulent flow which does not reach such a simple equilibrium. Consequently, the adjustment that has been made in the constants of the epsilon-transport equation to eliminate this singularity is not self-consistent since it is tantamount to artificially imposing an equilibrium structure on a turbulent flow which is known not to have one.

Demographic stagnation and decline in Spain: A cause for concern?

Directory of Open Access Journals (Sweden)

Serrano-Martínez José-María

2018-03-01

Full Text Available For years, the Spanish population has been rapidly ageing, showing signs of atony and stagnation. Between 1996 and 2007, in a phase of economic growth, the entry of foreign immigrants drove a global increase in population. But after the economic recession migratory flows show negative net balances. Our objective is to explain and confirm the demographic regression suffered by Spain. We are also interested in showing how the recent and intense immigration process has failed to generate significant changes in natural demographic characteristics and trends. National censuses, published by the National Institute of Statistics (INE, are our main source of demographic data. The analysis of the most recent relevant scientific literature has allowed us to compare opinions and discuss results. The data confirm an uncertain and worrying future for the Spanish population.

The role of atmospheric nuclear explosions on the stagnation of global warming in the mid 20th century

Science.gov (United States)

Fujii, Yoshiaki

2011-04-01

This study suggests that the cause of the stagnation in global warming in the mid 20th century was the atmospheric nuclear explosions detonated between 1945 and 1980. The estimated GST drop due to fine dust from the actual atmospheric nuclear explosions based on the published simulation results by other researchers (a single column model and Atmosphere-Ocean General Circulation Model) has served to explain the stagnation in global warming. Atmospheric nuclear explosions can be regarded as full-scale in situ tests for nuclear winter. The non-negligible amount of GST drop from the actual atmospheric explosions suggests that nuclear winter is not just a theory but has actually occurred, albeit on a small scale. The accuracy of the simulations of GST by IPCC would also be improved significantly by introducing the influence of fine dust from the actual atmospheric nuclear explosions into their climate models; thus, global warming behavior could be more accurately predicted.

Heat transfer in an axisymmetric stagnation flow at high Reynolds numbers on a cylinder using perturbation techniques

International Nuclear Information System (INIS)

Rahimi, A. B.

2003-01-01

Although there are many papers on the subject of heat transfer in an axisymmetric stagnation flow on a cylinder, the available knowledge is mainly for low Reynolds numbers and not much information exists for the same problem at large Reynolds numbers. In this work, the problem of heat transfer in an axisymmetric stagnation flow on a cylinder is solved at large Reynolds numbers using perturbation techniques. Starting from Navier-Stokes equations within a boundary layer approximation and using similarity transformations, the governing equations are obtained in the form of differential equations. The inverse of the Reynolds number is introduced as the perturbation parameter. This parameter appears in front of the highest-order terms and, as it tends to zero, reduces the order of the governing equations and produces singularities. In this paper, the flow field is divided into two regions; rapid changes in the region near wall and slow changes away from the wall. Thus, the flow is found to have dual-layer characteristics. Using inner and outer expansion produces uniform values of the relevant quantities

Standard Practice for Exposure of Solar Collector Cover Materials to Natural Weathering Under Conditions Simulating Stagnation Mode

CERN Document Server

American Society for Testing and Materials. Philadelphia

1992-01-01

1.1 This practice covers a procedure for the exposure of solar collector cover materials to the natural weather environment at elevated temperatures that approximate stagnation conditions in solar collectors having a combined back and edge loss coefficient of less than 1.5 W/(m2 · °C). 1.2 This practice is suitable for exposure of both glass and plastic solar collector cover materials. Provisions are made for exposure of single and double cover assemblies to accommodate the need for exposure of both inner and outer solar collector cover materials. 1.3 This practice does not apply to cover materials for evacuated collectors, photovoltaic cells, flat-plate collectors having a combined back and edge loss coefficient greater than 1.5 W/(m2 ·° C), or flat-plate collectors whose design incorporates means for limiting temperatures during stagnation. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard t...

Flow stagnation volume and abdominal aortic aneurysm growth: Insights from patient-specific computational flow dynamics of Lagrangian-coherent structures.

Science.gov (United States)

Joly, Florian; Soulez, Gilles; Garcia, Damien; Lessard, Simon; Kauffmann, Claude

2018-01-01

Abdominal aortic aneurysms (AAA) are localized, commonly-occurring dilations of the aorta. When equilibrium between blood pressure (loading) and wall mechanical resistance is lost, rupture ensues, and patient death follows, if not treated immediately. Experimental and numerical analyses of flow patterns in arteries show direct correlations between wall shear stress and wall mechano-adaptation with the development of zones prone to thrombus formation. For further insights into AAA flow topology/growth interaction, a workout of patient-specific computational flow dynamics (CFD) is proposed to compute finite-time Lyapunov exponents and extract Lagrangian-coherent structures (LCS). This computational model was first compared with 4-D phase-contrast magnetic resonance imaging (MRI) in 5 patients. To better understand the impact of flow topology and transport on AAA growth, hyperbolic, repelling LCS were computed in 1 patient during 8-year follow-up, including 9 volumetric morphologic AAA measures by computed tomography-angiography (CTA). LCS defined barriers to Lagrangian jet cores entering AAA. Domains enclosed between LCS and the aortic wall were considered to be stagnation zones. Their evolution was studied during AAA growth. Good correlation - 2-D cross-correlation coefficients of 0.65, 0.86 and 0.082 (min, max, SD) - was obtained between numerical simulations and 4-D MRI acquisitions in 6 specific cross-sections from 4 patients. In follow-up study, LCS divided AAA lumens into 3 dynamically-isolated zones: 2 stagnation volumes lying in dilated portions of the AAA, and circulating volume connecting the inlet to the outlet. The volume of each zone was tracked over time. Although circulating volume remained unchanged during 8-year follow-up, the AAA lumen and main stagnation zones grew significantly (8 cm 3 /year and 6 cm 3 /year, respectively). This study reveals that transient transport topology can be quantified in patient-specific AAA during disease progression

Stagnation point flow towards nonlinear stretching surface with Cattaneo-Christov heat flux

Science.gov (United States)

Hayat, T.; Zubair, M.; Ayub, M.; Waqas, M.; Alsaedi, A.

2016-10-01

Here the influence of the non-Fourier heat flux in a two-dimensional (2D) stagnation point flow of Eyring-Powell liquid towards a nonlinear stretched surface is reported. The stretching surface is of variable thickness. Thermal conductivity of fluid is taken temperature-dependent. Ordinary differential systems are obtained through the implementation of meaningful transformations. The reduced non-dimensional expressions are solved for the convergent series solutions. Convergence interval is obtained for the computed solutions. Graphical results are displayed and analyzed in detail for the velocity, temperature and skin friction coefficient. The obtained results reveal that the temperature gradient enhances when the thermal relaxation parameter is increased.

The Relationship Between Children's Academic Performance and Achievement Accountability

Science.gov (United States)

Clifford, Margaret M.; Cleary, T. Anne

1972-01-01

Purpose of the study is to examine relationships between internality and achievement-related variables in a performance situation where students determine the difficulty level at which they desire to work. (Authors)

The Role of Achievement Goals in the Development of Interest: Reciprocal Relations between Achievement Goals, Interest, and Performance

Science.gov (United States)

Harackiewicz, Judith M.; Durik, Amanda M.; Barron, Kenneth E.; Linnenbrink-Garcia, Lisa; Tauer, John M.

2008-01-01

The dynamics of individual and situational interest and academic performance were examined in the college classroom and 7 semesters later in conjunction with achievement goals. At the beginning of an introductory psychology course, participants reported their initial interest in psychology, achievement goals, and situational interest in course…

Quantitative Guidance for Stove Usage and Performance to Achieve Health and Environmental Targets.

Science.gov (United States)

Johnson, Michael A; Chiang, Ranyee A

2015-08-01

Displacing the use of polluting and inefficient cookstoves in developing countries is necessary to achieve the potential health and environmental benefits sought through clean cooking solutions. Yet little quantitative context has been provided on how much displacement of traditional technologies is needed to achieve targets for household air pollutant concentrations or fuel savings. This paper provides instructive guidance on the usage of cooking technologies required to achieve health and environmental improvements. We evaluated different scenarios of displacement of traditional stoves with use of higher performing technologies. The air quality and fuel consumption impacts were estimated for these scenarios using a single-zone box model of indoor air quality and ratios of thermal efficiency. Stove performance and usage should be considered together, as lower performing stoves can result in similar or greater benefits than a higher performing stove if the lower performing stove has considerably higher displacement of the baseline stove. Based on the indoor air quality model, there are multiple performance-usage scenarios for achieving modest indoor air quality improvements. To meet World Health Organization guidance levels, however, three-stone fire and basic charcoal stove usage must be nearly eliminated to achieve the particulate matter target (< 1-3 hr/week), and substantially limited to meet the carbon monoxide guideline (< 7-9 hr/week). Moderate health gains may be achieved with various performance-usage scenarios. The greatest benefits are estimated to be achieved by near-complete displacement of traditional stoves with clean technologies, emphasizing the need to shift in the long term to near exclusive use of clean fuels and stoves. The performance-usage scenarios are also provided as a tool to guide technology selection and prioritize behavior change opportunities to maximize impact.

Hypothetical model of factors determining performance and sports achievement in team sports

Directory of Open Access Journals (Sweden)

Trninić Marko

2011-01-01

Full Text Available The objective of this paper is formation of a comprehensive hypothetical dynamic interactional process model structured by assumed constructs, i.e. processes or mechanisms that obtain real features and influences on athlete's performance and athletic achievement. Thus there are formed and assumed reciprocal relations between high training and competition - based stress as the input variable, cognitive appraisal and interpretation as the mediator, and mood state as the moderator based on the development of the dynamic systems theory. Also, proposed model uses basic assumptions of the Action-Theory approach and it is in accordance with the contemporary socialcognitive view of team functioning in sports. Within the process model, the output variables are measures of efficacy evident through athlete's individual and team performance and athletic achievement. The situation, the team and athlete attributes, the performance and the athletic achievement are joined variables, and the individual and the collective efficacy are the consequence of their reciprocal interaction. Therefore, there are complex and reciprocal interactive processes in real sports and explorative situations amongst the attributes of athlete and team and the behaviour and situation that determine performance and athletic achievement. This is probably the result of an integrated network of reciprocal multi-causal activity of a set of stated assumed constructs from different theories. Thus the hypothetical model is an effort to describe elaborate correlations and/or interdependencies between internal and external determinants which presumably affect athlete's performance and athletic achievement.

Test Anxiety and Academic Performance among Undergraduates: The Moderating Role of Achievement Motivation.

Science.gov (United States)

Balogun, Anthony Gbenro; Balogun, Shyngle Kolawole; Onyencho, Chidi Victor

2017-02-13

This study investigated the moderating role of achievement motivation in the relationship between test anxiety and academic performance. Three hundred and ninety three participants (192 males and 201 females) selected from a public university in Ondo State, Nigeria using a purposive sampling technique, participated in the study. They responded to measures of test anxiety and achievement motivation. Three hypotheses were tested using moderated hierarchical multiple regression analysis. Results showed that test anxiety had a negative impact on academic performance (β = -.23; p motivation had a positive impact on academic performance (β = .38; p motivation significantly moderated the relationship between test anxiety and academic performance (β = .10; p students' achievement motivation.

On the Analytical Solution of Non-Orthogonal Stagnation Point Flow towards a Stretching Sheet

DEFF Research Database (Denmark)

Kimiaeifar, Amin; Bagheri, G. H.; Barari, Amin

2011-01-01

An analytical solution for non-orthogonal stagnation point for the steady flow of a viscous and incompressible fluid is presented. The governing nonlinear partial differential equations for the flow field are reduced to ordinary differential equations by using similarity transformations existed...... in the literature and are solved analytically by means of the Homotopy Analysis Method (HAM). The comparison of results from this paper and those published in the literature confirms the precise accuracy of the HAM. The resulting analytical equation from HAM is valid for entire physical domain and effective...

Impedance spectroscopy and structural properties of the perovskite-like Sn(Ba,Sr)O3 stagnate

International Nuclear Information System (INIS)

Cuervo Farfán, J.; Olaya, J.J.; Vera López, E.; Landínez Téllez, D.A.; Roa-Rojas, J.

2012-01-01

An exhaustive study of structural, electrical and transport properties on the perovskite stagnate Sn(Ba,Sr)O 3 was performed. Samples of SnBa 1-x Sr x O 3 with 0≤x≤1.00 were prepared by the solid state reaction method. The crystallographic structure was studied by X-ray diffraction experiments and Rietveld refinement using the GSAS code. Results reveal the material synthesized in a cubic structure (space group Pm3-bar m, no. 221) for 0≤x≤0.50 and in an orthorhombic (space group Pnma, no. 62) for x>0.50. The approximate grain size was found from experiments' Scanning Electron Microscopy. The electric response was studied by the Impedance Spectroscopy technique from 10.0 mHz up to 0,10 MHz. Electric polarization measurements for SnSrO 3 and SnBaO 3 were determined through curves of polarization as a function of applied electric field, which reveal the ferroelectric character of the material. From the saturation polarization the dielectric constants of materials were calculated.

Performance-approach and performance-avoidance classroom goals and the adoption of personal achievement goals.

Science.gov (United States)

Schwinger, Malte; Stiensmeier-Pelster, Joachim

2011-12-01

Students' perceptions of classroom goals influence their adoption of personal goals. To assess different forms of classroom goals, recent studies have favoured an overall measure of performance classroom goals, compared to a two-dimensional assessment of performance-approach and performance-avoidance classroom goals (PAVCG). This paper considered the relationship between students' perceptions of classroom goals and their endorsement of personal achievement goals. We proposed that three (instead of only two) classroom goals need to be distinguished. We aimed to provide evidence for this hypothesis by confirmatory factor analysis (CFA) and also by divergent associations between the respective classroom goal and students' personal goal endorsement. A total of 871 (474 female) 10th grade students from several German high schools participated in this study. Students responded to items assessing their perception of mastery, performance-approach, and performance-avoidance goals in the classroom. Additionally, the students reported how much they personally pursue mastery, performance-approach, and performance-avoidance goals. All items referred to German as a specific school subject. RESULTS.A CFA yielded empirical support for the proposed distinction of three (instead of only two) different kinds of classroom goals. Moreover, in hierarchical linear modelling (HLM) analyses all three classroom goals showed unique associations with students' personal goal adoption. The findings emphasized the need to distinguish performance-approach and PAVCG. Furthermore, our results suggest that multiple classroom goals have interactive effects on students' personal achievement strivings. ©2010 The British Psychological Society.

Bulk damping of sound in superfluid 3He--4He under stagnation of the normal component

International Nuclear Information System (INIS)

Karchava, T.A.; Sanikidze, D.G.; Chkhaidze, N.D.

1983-01-01

The propagation of waves in superfluid 3 He-- 4 He solutions is considered under partial stagnation of the normal component. The wave processes in capillaries are presented as a superposition of the first sound, second sound, and viscous and diffusion waves. The damping coefficients are calculated for the modified first sound and for the thermal wave in superfluid 3 He-- 4 He solutions and related to the viscosity, thermal conductivity, diffusion, barodiffusion, and thermodiffusion coefficients

Dynamic Effects of Performance-Avoidance Goal Orientation on Student Achievement in Language and Mathematics.

Science.gov (United States)

Stamovlasis, Dimitrios; Gonida, Sofia-Eleftheria N

2018-07-01

The present study used achievement goal theory (AGT) as a theoretical framework and examined the role of mastery and performance goals, both performance-approach and performance-avoidance, on school achieve-ment within the nonlinear dynamical systems (NDS) perspective. A series of cusp catastrophe models were applied on students' achievement in a number of school subjects, such as mathematics and language for elementary school and algebra, geometry, ancient and modern Greek language for high school, using achievement goal orientations as control variables. The participants (N=224) were students attending fifth and eighth grade (aged 11 and 14, respectively) in public schools located in northern Greece. Cusp analysis based on the probability density function was carried out by two procedures, the maximum likelihood and the least squares. The results showed that performance-approach goals had no linear effect on achievement, while the cusp models implementing mastery goals as the asymmetry factor and performance-avoidance as the bifurcation, proved superior to their linear alternatives. The results of the study based on NDS support the multiple goal perspective within AGT. Theoretical issues, educational implications and future directions are discussed.

The impact of the achievement motive on athletic performance in adolescent football players.

Science.gov (United States)

Zuber, Claudia; Conzelmann, Achim

2014-01-01

Researchers largely agree that there is a positive relationship between achievement motivation and athletic performance, which is why the achievement motive is viewed as a potential criterion for talent. However, the underlying mechanism behind this relationship remains unclear. In talent and performance models, main effect, mediator and moderator models have been suggested. A longitudinal study was carried out among 140 13-year-old football talents, using structural equation modelling to determine which model best explains how hope for success (HS) and fear of failure (FF), which are the aspects of the achievement motive, motor skills and abilities that affect performance. Over a period of half a year, HS can to some extent explain athletic performance, but this relationship is not mediated by the volume of training, sport-specific skills or abilities, nor is the achievement motive a moderating variable. Contrary to expectations, FF does not explain any part of performance. Aside from HS, however, motor abilities and in particular skills also predict a significant part of performance. The study confirms the widespread assumption that the development of athletic performance in football depends on multiple factors, and in particular that HS is worth watching in the medium term as a predictor of talent.

One- and two-dimensional density and temperature measurements of an argon-neon Z-pinch plasma at stagnation

International Nuclear Information System (INIS)

Wong, K.L.; Springer, P.T.; Hammer, J.H.; Iglesias, C.A.; Osterheld, A.L.; Foord, M.E.; Bruns, H.C.; Emig, J.A.; Deeney, C.

1996-10-01

In order to benchmark and improve current 2D radiation magnetohydrodynamic (MHD) models of Z-pinch plasmas, we have performed experiments which characterize the plasma -conditions at stagnation. In the experiments the SATURN pulsed power facility at Sandia National Laboratory was used to create an imploding -Ar-Ne plasma. An absolutely calibrated, high resolution space- and time- resolving Johann crystal spectrometer was used to infer the electron temperature Te from the slope of the hydrogenlike Ne free-bound continuum, and the ion density ni from the Stark broadening of the Ar heliunlike Rydberg series. 2D electron temperature profiles of the plasma are obtained from a set of imaging crystals also focused on the Ne free-bound continuum. We shot two types of gas nozzles in the experiment, annular and uniform fill which varies the amount of mass in the plasma. 2D local thermodynamic equilibrium (LTE) and non-LTE MM models predict a radiating region denser and cooler than measured

Surface kinetics for catalytic combustion of hydrogen-air mixtures on platinum at atmospheric pressure in stagnation flows

Science.gov (United States)

Ikeda, H.; Sato, J.; Williams, F. A.

1995-03-01

Experimental studies of the combustion of premixed hydrogen-air mixtures impinging on the surface of a heated platinum plate at normal atmospheric pressure were performed and employed to draw inferences concerning surface reaction mechanisms and rate parameters applicable under practical conditions of catalytic combustion. Plate and gas temperatures were measured by thermocouples, and concentration profiles of major stable species in the gas were measured by gas-chromatographic analyses of samples withdrawn by quartz probes. In addition, ignition and extinction phenomena were recorded and interpreted with the aid of a heat balance at the surface and a previous flow-field analysis of the stagnation-point boundary layer. From the experimental and theoretical results, conclusions were drawn concerning the surface chemical-kinetic mechanisms and values of the elementary rate parameters that are consistent with the observations. In particular, the activation energy for the surface oxidation step H + OH → H 2O is found to be appreciably less at these high surface coverages than in the low-coverage limit.

Analysis of stagnation point flow of an upper-convected Maxwell fluid

Directory of Open Access Journals (Sweden)

Joseph E. Paullet

2017-12-01

Full Text Available Several recent papers have investigated the two-dimensional stagnation point flow of an upper-convected Maxwell fluid by employing a similarity change of variable to reduce the governing PDEs to a nonlinear third order ODE boundary value problem (BVP. In these previous works, the BVP was studied numerically and several conjectures regarding the existence and behavior of the solutions were made. The purpose of this article is to mathematically verify these conjectures. We prove the existence of a solution to the BVP for all relevant values of the elasticity parameter. We also prove that this solution has monotonically increasing first derivative, thus verifying the conjecture that no ``overshoot'' of the boundary condition occurs. Uniqueness results are presented for a large range of parameter space and bounds on the skin friction coefficient are calculated.

Inertioelastic Flow Instability at a Stagnation Point

Science.gov (United States)

Burshtein, Noa; Zografos, Konstantinos; Shen, Amy Q.; Poole, Robert J.; Haward, Simon J.

2017-10-01

A number of important industrial applications exploit the ability of small quantities of high molecular weight polymer to suppress instabilities that arise in the equivalent flow of Newtonian fluids, a particular example being turbulent drag reduction. However, it can be extremely difficult to probe exactly how the polymer acts to, e.g., modify the streamwise near-wall eddies in a fully turbulent flow. Using a novel cross-slot flow configuration, we exploit a flow instability in order to create and study a single steady-state streamwise vortex. By quantitative experiment, we show how the addition of small quantities (parts per million) of a flexible polymer to a Newtonian solvent dramatically affects both the onset conditions for this instability and the subsequent growth of the axial vorticity. Complementary numerical simulations with a finitely extensible nonlinear elastic dumbbell model show that these modifications are due to the growth of polymeric stress within specific regions of the flow domain. Our data fill a significant gap in the literature between the previously reported purely inertial and purely elastic flow regimes and provide a link between the two by showing how the instability mode is transformed as the fluid elasticity is varied. Our results and novel methods are relevant to understanding the mechanisms underlying industrial uses of weakly elastic fluids and also to understanding inertioelastic instabilities in more confined flows through channels with intersections and stagnation points.

The effect of mixing rates on the formation and growth of condensation aerosols in a model stagnation flow

KAUST Repository

Alshaarawi, Amjad; Bisetti, Fabrizio

2015-01-01

A steady, laminar stagnation flow configuration is adopted to investigate numerically the interaction between condensing aerosol particles and gas-phase transport across a canonical mixing layer. The mixing rates are varied by adjusting the velocity and length scales of the stagnation flow parametrically. The effect of mixing rates on particle concentration, polydispersity, and mean droplet diameter is explored and discussed. This numerical study reveals a complex response of the aerosol to varying flow times. Depending on the flow time, the variation of the particle concentration in response to varying mixing rates falls into one of the two regimes. For fast mixing rates, the number density and volume fraction of the condensing particles increase with residence time (nucleation regime). On the contrary, for low mixing rates, number density decreases with residence time and volume fraction reaches a plateau (condensation regime). It is shown that vapor scavenging by the aerosol phase is key to explaining the transition between these two regimes. The results reported here are general and illustrate genuine features of the evolution of aerosols forming by condensation of supersaturated vapor from heat and mass transport across mixing layers.

The effect of mixing rates on the formation and growth of condensation aerosols in a model stagnation flow

KAUST Repository

Alshaarawi, Amjad

2015-03-01

A steady, laminar stagnation flow configuration is adopted to investigate numerically the interaction between condensing aerosol particles and gas-phase transport across a canonical mixing layer. The mixing rates are varied by adjusting the velocity and length scales of the stagnation flow parametrically. The effect of mixing rates on particle concentration, polydispersity, and mean droplet diameter is explored and discussed. This numerical study reveals a complex response of the aerosol to varying flow times. Depending on the flow time, the variation of the particle concentration in response to varying mixing rates falls into one of the two regimes. For fast mixing rates, the number density and volume fraction of the condensing particles increase with residence time (nucleation regime). On the contrary, for low mixing rates, number density decreases with residence time and volume fraction reaches a plateau (condensation regime). It is shown that vapor scavenging by the aerosol phase is key to explaining the transition between these two regimes. The results reported here are general and illustrate genuine features of the evolution of aerosols forming by condensation of supersaturated vapor from heat and mass transport across mixing layers.

Application of turbulence modeling to predict surface heat transfer in stagnation flow region of circular cylinder

Science.gov (United States)

Wang, Chi R.; Yeh, Frederick C.

1987-01-01

A theoretical analysis and numerical calculations for the turbulent flow field and for the effect of free-stream turbulence on the surface heat transfer rate of a stagnation flow are presented. The emphasis is on the modeling of turbulence and its augmentation of surface heat transfer rate. The flow field considered is the region near the forward stagnation point of a circular cylinder in a uniform turbulent mean flow. The free stream is steady and incompressible with a Reynolds number of the order of 10 to the 5th power and turbulence intensity of less than 5 percent. For this analysis, the flow field is divided into three regions: (1) a uniform free-stream region where the turbulence is homogeneous and isotropic; (2) an external viscid flow region where the turbulence is distorted by the variation of the mean flow velocity; and, (3) an anisotropic turbulent boundary layer region over the cylinder surface. The turbulence modeling techniques used are the kappa-epsilon two-equation model in the external flow region and the time-averaged turbulence transport equation in the boundary layer region. The turbulence double correlations, the mean velocity, and the mean temperature within the boundary layer are solved numerically from the transport equations. The surface heat transfer rate is calculated as functions of the free-stream turbulence longitudinal microlength scale, the turbulence intensity, and the Reynolds number.

Impedance spectroscopy and structural properties of the perovskite-like Sn(Ba,Sr)O{sub 3} stagnate

Energy Technology Data Exchange (ETDEWEB)

Cuervo Farfan, J. [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, AA 5997, Bogota DC (Colombia); Ciencias Basicas, Universidad Manuela Beltran, Bogota DC (Colombia); Olaya, J.J. [Departamento de Ingenieria Mecanica y Mecatronica, Universidad Nacional de Colombia, Bogota DC (Colombia); Vera Lopez, E. [Grupo de Superficies, Electroquimica y Corrosion, Universidad Pedagogica y Tecnologica de Colombia, Tunja (Colombia); Landinez Tellez, D.A. [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, AA 5997, Bogota DC (Colombia); Roa-Rojas, J., E-mail: jroar@unal.edu.co [Grupo de Fisica de Nuevos Materiales, Departamento de Fisica, Universidad Nacional de Colombia, AA 5997, Bogota DC (Colombia)

2012-08-15

An exhaustive study of structural, electrical and transport properties on the perovskite stagnate Sn(Ba,Sr)O{sub 3} was performed. Samples of SnBa{sub 1-x}Sr{sub x}O{sub 3} with 0{<=}x{<=}1.00 were prepared by the solid state reaction method. The crystallographic structure was studied by X-ray diffraction experiments and Rietveld refinement using the GSAS code. Results reveal the material synthesized in a cubic structure (space group Pm3-bar m, no. 221) for 0{<=}x{<=}0.50 and in an orthorhombic (space group Pnma, no. 62) for x>0.50. The approximate grain size was found from experiments' Scanning Electron Microscopy. The electric response was studied by the Impedance Spectroscopy technique from 10.0 mHz up to 0,10 MHz. Electric polarization measurements for SnSrO{sub 3} and SnBaO{sub 3} were determined through curves of polarization as a function of applied electric field, which reveal the ferroelectric character of the material. From the saturation polarization the dielectric constants of materials were calculated.

The Effect of Teacher Performance in Implementation of The 2013 Curriculum Toward Chemistry Learning Achievement

Science.gov (United States)

Dewi, L. P.; Djohar, A.

2018-04-01

This research is a study about implementation of the 2013 Curriculum on Chemistry subject. This study aims to determine the effect of teacher performance toward chemistry learning achievement. The research design involves the independent variable, namely the performance of Chemistry teacher, and the dependent variable that is Chemistry learning achievement which includes the achievement in knowledge and skill domain. The subject of this research are Chemistry teachers and High School students in Bandung City. The research data is obtained from questionnaire about teacher performance assessed by student and Chemistry learning achievement from the students’ report. Data were analyzed by using MANOVA test. The result of multivariate significance test shows that there is a significant effect of teacher performance toward Chemistry learning achievement in knowledge and skill domain with medium effect size.

Botulinum Toxin A for Oral Cavity Cancer Patients: In Microsurgical Patients BTX Injections in Major Salivary Glands Temporarily Reduce Salivary Production and the Risk of Local Complications Related to Saliva Stagnation

OpenAIRE

Corradino, Bartolo; Lorenzo, Sara Di; Moschella, Francesco

2012-01-01

In patients suffering from oral cavity cancer surgical treatment is complex because it is necessary to remove carcinoma and lymph node metastasis (through a radical unilateral or bilateral neck dissection) and to reconstruct the affected area by means of free flaps. The saliva stagnation in the post-operative period is a risk factor with regard to local complications. Minor complications related to saliva stagnation (such as tissue maceration and wound dehiscence) could become major complicat...

The Problem: Low-Achieving Districts and Low-Performing Boards

Directory of Open Access Journals (Sweden)

David E. Lee

2014-10-01

Full Text Available Effective school districts maintain superintendent and school board collegiality which can foster success and connectedness among members. Delagardelle and Alsbury (2008 found that superintendents and board members are not consistent in their perceptions about the work the board does, and Glass (2007 found that states do not require boards to undergo evaluation for effectiveness. In the current study, 115 board meetings were observed using the School Board Video Project (SBVP survey, which was created in 2012 by researchers to uncover school board meetings’ effectiveness. MANOVA, Univariate ANOVA, and Pearson Chi-Square test results revealed significant differences between low-, medium-, and high-performing districts’ school board meetings. Evidence indicated that low-performing districts’ board meetings were: less orderly; had less time spent on student achievement; lacked respectful and attentive engagement across speakers; had board meeting members who seemed to advance their own agenda; had less effective working relationships among the governance team; had fewer board members who relied on the superintendent for advice and input; had one member, other than the board president, stand out for taking excessive time during meetings; and did not focus on policy items as much as high- and medium-performing school districts. The research concluded that more school board members from low-performing districts needed training to improve their effectiveness. Furthermore, highly refined and target-enhanced school board training programs might lead to lasting governance success and more effective teaming that could improve district, and ultimately, student achievement.

Effects of plasma jet parameters, ionization, thermal conduction, and radiation on stagnation conditions of an imploding plasma liner

Science.gov (United States)

Stanic, Milos

The disciplines of High Energy Density Physics (HEDP) and Inertial Confinement Fusion (ICF) are characterized by hypervelocity implosions and strong shocks. The Plasma Liner Experiment (PLX) is focused on reaching HEDP and/or ICF relevant regimes in excess of 1 Mbar peak pressure by the merging and implosion of discrete plasma jets, as a potentially efficient path towards these extreme conditions in a laboratory. In this work we have presented the first 3D simulations of plasma liner, formation, and implosion by the merging of discrete plasma jets in which ionization, thermal conduction, and radiation are all included in the physics model. The study was conducted by utilizing a smoothed particle hydrodynamics code (SPHC) and was a part of the plasma liner experiment (PLX). The salient physics processes of liner formation and implosion are studied, namely vacuum propagation of plasma jets, merging of the jets (liner forming), implosion (liner collapsing), stagnation (peak pressure), and expansion (rarefaction wave disassembling the target). Radiative transport was found to significantly reduce the temperature of the liner during implosion, thus reducing the thermal expansion rates and leaving more pronounced gradients in the plasma liner during the implosion compared with ideal hydrodynamic simulations. These pronounced gradients lead to a greater sensitivity of initial jet geometry and symmetry on peak pressures obtained. Accounting for ionization and transport, many cases gave higher peak pressures than the ideal hydrodynamic simulations. Scaling laws were developed accordingly, creating a non-dimensional parameter space in which performance of an imploding plasma jet liner can be estimated. It is shown that HEDP regimes could be reached with ≈ 5 MJ of liner energy, which would translate to roughly 10 to 20 MJ of stored (capacitor) energy. This is a potentially significant improvement over the currently available means via ICF of achieving HEDP and nuclear

Stagnation and Storage of Strongly Depleted Melts in Slow-Ultraslow Spreading Oceans: Evidence from the Ligurian Tethys

Science.gov (United States)

Piccardo, Giovanni; Guarnieri, Luisa; Padovano, Matteo

2013-04-01

Our studies of Alpine-Apennine ophiolite massifs (i.e., Lanzo, Voltri, Ligurides, Corsica) show that the Jurassic Ligurian Tethys oceanic basin was a slow-ultraslow spreading basin, characterized by the exposures on the seafloor of mantle peridotites with extreme compositional variability. The large majority of these peridotites are made of depleted spinel harzburgites and plagioclase peridotites. The former are interpreted as reactive peridotites formed by the reactive percolation of under-saturated, strongly trace element depleted asthenospheric melts migrated by porous flow through the mantle lithosphere. The latter are considered as refertilized peridotites formed by peridotite impregnation by percolated silica-saturated, strongly trace element depleted melts. Strongly depleted melts were produced as low-degrees, single melt increments by near fractional melting of the passively upwelling asthenosphere during the rifting stage of the basin. They escaped single melt increment aggregation, migrated isolated through the mantle lithosphere by reactive porous or channeled flow before oceanic opening, and were transformed into silica-saturated derivative liquids that underwent entrapment and stagnation in the shallow mantle lithosphere forming plagioclase-enriched peridotites. Widespread small bodies of strongly depleted gabbro-norites testify for the local coalescence of these derivative liquids. These melts never reached the surface (i.e., the hidden magmatism), since lavas with their composition have never been found in the basin. Subsequently, aggregated MORB melts upwelled within replacive dunite channels (as evidenced by composition of magmatic clinopyroxenes in dunites), intruded at shallow levels as olivine gabbro bodies and extruded as basaltic lavas, to form the crustal rocks of the oceanic lithosphere (i.e., the oceanic magmatism). Km-scale bodies of MORB olivine gabbros were intruded into the plagioclase-enriched peridotites, which were formed in the

Performance on large-scale science tests: Item attributes that may impact achievement scores

Science.gov (United States)

Gordon, Janet Victoria

Significant differences in achievement among ethnic groups persist on the eighth-grade science Washington Assessment of Student Learning (WASL). The WASL measures academic performance in science using both scenario and stand-alone question types. Previous research suggests that presenting target items connected to an authentic context, like scenario question types, can increase science achievement scores especially in underrepresented groups and thus help to close the achievement gap. The purpose of this study was to identify significant differences in performance between gender and ethnic subgroups by question type on the 2005 eighth-grade science WASL. MANOVA and ANOVA were used to examine relationships between gender and ethnic subgroups as independent variables with achievement scores on scenario and stand-alone question types as dependent variables. MANOVA revealed no significant effects for gender, suggesting that the 2005 eighth-grade science WASL was gender neutral. However, there were significant effects for ethnicity. ANOVA revealed significant effects for ethnicity and ethnicity by gender interaction in both question types. Effect sizes were negligible for the ethnicity by gender interaction. Large effect sizes between ethnicities on scenario question types became moderate to small effect sizes on stand-alone question types. This indicates the score advantage the higher performing subgroups had over the lower performing subgroups was not as large on stand-alone question types compared to scenario question types. A further comparison examined performance on multiple-choice items only within both question types. Similar achievement patterns between ethnicities emerged; however, achievement patterns between genders changed in boys' favor. Scenario question types appeared to register differences between ethnic groups to a greater degree than stand-alone question types. These differences may be attributable to individual differences in cognition

Social jetlag, academic achievement and cognitive performance: Understanding gender/sex differences.

Science.gov (United States)

Díaz-Morales, Juan F; Escribano, Cristina

2015-01-01

Adolescents in high school suffer from circadian misalignment, undersleeping on weekdays and oversleeping on weekends. Since high schools usually impose early schedules, adolescents suffer from permanent social jetlag (SJL) and thus are a suitable population to study the effects of SJL on both academic and cognitive performance. In this study, 796 adolescents aged 12-16 years reported information about their sleep habits, morningness-eveningness (M-E), cognitive abilities and grade point average (GPA). Time in bed on both weekdays and weekends was not related to cognitive abilities, and only time in bed on weekdays was related to academic achievement. SJL was negatively related to academic achievement, cognitive abilities (except for vocabulary and verbal fluency abilities) and general cognitive ability (g), whereas M-E was slightly positively related to academic achievement and marginally negatively related to inductive reasoning. Results separated by sex/gender indicated that SJL may be more detrimental to girls' performance, as it was negatively related to a greater number of cognitive abilities and GPA.

Linear stability analysis of laminar flow near a stagnation point in the slip flow regime

Science.gov (United States)

Essaghir, E.; Oubarra, A.; Lahjomri, J.

2017-12-01

The aim of the present contribution is to analyze the effect of slip parameter on the stability of a laminar incompressible flow near a stagnation point in the slip flow regime. The analysis is based on the traditional normal mode approach and assumes parallel flow approximation. The Orr-Sommerfeld equation that governs the infinitesimal disturbance of stream function imposed to the steady main flow, which is an exact solution of the Navier-Stokes equation satisfying slip boundary conditions, is obtained by using the powerful spectral Chebyshev collocation method. The results of the effect of slip parameter K on the hydrodynamic characteristics of the base flow, namely the velocity profile, the shear stress profile, the boundary layer, displacement and momentum thicknesses are illustrated and discussed. The numerical data for these characteristics, as well as those of the eigenvalues and the corresponding wave numbers recover the results of the special case of no-slip boundary conditions. They are found to be in good agreement with previous numerical calculations. The effects of slip parameter on the neutral curves of stability, for two-dimensional disturbances in the Reynolds-wave number plane, are then obtained for the first time in the slip flow regime for stagnation point flow. Furthermore, the evolution of the critical Reynolds number against the slip parameter is established. The results show that the critical Reynolds number for instability is significantly increased with the slip parameter and the flow turn out to be more stable when the effect of rarefaction becomes important.

To compare the efficacy of two kinds of Zhizhu pills in the treatment of functional dyspepsia of spleen-deficiency and qi-stagnation syndrome:a randomized group sequential comparative trial

Science.gov (United States)

2011-01-01

Background In Traditional Chinese Medicine (TCM) theory, functional dyspepsia (FD) can be divided into different syndromes according to different clinical symptoms and signs, and the most common one is spleen-deficiency and qi-stagnation syndrome that can be treated by Chinese traditional patent medicine ---- two kinds of Zhizhu pills, between which the primary difference in ingredients is that one contains immature orange fruit of Citrus aurantium L.(IFCA) and the other contains that of Citrus sinensis Osbeck (IFCS). The trial's objective was to compare the efficacy of two kinds of Zhizhu pills on symptom changes in patients with FD of spleen-deficiency and qi-stagnation syndrome. Methods A randomized, group sequential, double-blinded, multicenter trial was conducted in patients with FD of spleen-deficiency and qi-stagnation syndrome at 3 hospitals in Beijing between June 2003 and May 2005. Participants were randomly allocated into two groups (IFCA group and IFCS group) in a 1:1 ratio, and respectively took one of the two kinds of Zhizhu pills orally, 6 g each time, 3 times a day, for 4 weeks. Statistical analysis was performed with use of a group sequential method, the triangular test (TT). Results A total of 163 patients were randomized, and 3 patients were excluded from analysis because of early dropouts, leaving 160 patients (IFCA group: n = 82; IFCS group: n = 78) for statistical analysis. Three interim analyses were done after 62, 116, and 160 patients had completed their 4-week treatment, respectively. At the third interim analysis, the sample path crossed the upper boundary and the trial was stopped, the cure-markedly effective rates were 45% for IFCS group and 67% for IFCA group, respectively, the one-sided p-value was 0.0036, the median unbiased estimate of the odds ratio (OR) for the benefit of IFCA relative to IFCS was 2.91 with 95%CI: 1.40 to 6.06. No adverse events were observed in the two groups. Conclusions Zhizhu pills containing IFCA was superior

[Comparative analysis on the biological basis of blood stasis syndrome induced by qi-stagnation and qi-deficiency in patients with unstable angina pectoris].

Science.gov (United States)

Ren, Jian-xun; Liu, Jian-xun; Lin, Cheng-ren

2010-04-01

To comparatively analyse the objective characteristics of different syndrome types of qi-disturbance-induced blood stasis syndrome (QDBS) in the pathogenetic evolution of unstable angina coronary heart disease (UA-CHD). Seventy-eight patients with UA-CHD of QDBS were differentiated into 2 groups: 55 in the qi-deficiency-induced blood-stasis syndrome group (A) and 23 in the qi-stagnation-induced blood-stasis syndrome group (B). The comparative analysis on them was carried out through comparing their blood pressure, glucose and lipid metabolisms, coagulation function, thyroid function and inflammation reaction changes, etc. In the pathogenetic process of qi-disturbance induced blood stasis, the initiating age, levels of HbA1c, TSH, PT and APTT between the two groups were significantly different (P emotional stress is possibly the essence of qi-stagnation induced blood stasis syndrome.

Renewable Energy Certificate and Perform, Achieve, Trade mechanisms to enhance the energy security for India

International Nuclear Information System (INIS)

Kumar, Rajesh; Agarwala, Arun

2013-01-01

The Renewable Energy Certificate and Perform Achieve Trade mechanisms in India are designed to target energy generation and saving, respectively, in line with Clean Development Mechanism implemented by United Nations Framework Convention on Climate Change. The Renewable Energy Certificate System is a voluntary regulation in India for renewable energy generators and is designed for effective implementation of inter-state transactions by introducing the Renewable Purchase Obligation regulation for consumers and a flexible trading platform for transactions across the country. Another initiative, the Perform Achieve Trade scheme, is an enhanced energy efficiency trading mechanism based on consumption targets that require large energy user sectors to improve efficiency by 1–2% per year. The Perform Achieve Trade programme has introduced mechanisms for the identification of industry sector, designated customer, specific energy consumption and target setting. The Perform Achieve Trade design issues are in test phase in the first cycle of the scheme which will run from 2012 to 2015. This paper discusses key design issues about boundary and target setting for Renewable Energy Certificate and Perform Achieve Trade energy saving certificate (ESCert) A data sharing and trading mechanism for Perform Achieve Trade is also proposed for review and coordination among regulator, designated consumers and traders in the market. - Highlights: ► Renewable Energy Certificate’ and ‘Perform Achieve Trade’ are energy certification programmes. ► REC and PAT programme implementation and the institutional network work are presented. ► The trading and communication network propose for possible linkage between REC, PAT and CDM. ► Independent associations in parallel with CERC and BEE are redefined for two tier review of scheme

Role Overload, Role Self Distance, Role Stagnation as Determinants of Job Satisfaction and Turnover Intention in Banking Sector

Science.gov (United States)

Kunte, Monica; Gupta, Priya; Bhattacharya, Sonali; Neelam, Netra

2017-01-01

Purpose: This study examined the relationship of the organizational role stress: Role overload, role self-distance, and role stagnation with job satisfaction and turnover intention with a sample of banking employees in India. Methodology: In this research, we used the RODS scale developed by Prohit and Pareek (2010) for measuring occupational role scale. The reliability of the scale came out to be 0.71. Findings: The majority of employees of all ranks, in both private and public sector banks, suffer from high role stress of all types. It was found that role overload and role stagnation are inversely associated with banking employees' job satisfaction. Private sector bank employees have more role stress and more unsatisfied than employees of public sector banks. Employees Turnover intention was found to be positively impacted by job satisfaction, contrary to many other studies. Possible reasons have been suggested. Job satisfaction was found to play a partial mediating role in the relationship between role overload and turnover intention with 40% mediation. Further, employees with longer tenure (work experience) have less role stress and are more satisfied. Originality: This study is unique in the sense there is hardly any study linking role stress to job satisfaction and turnover intention, specially in Indian context. PMID:29200554

Role Overload, Role Self Distance, Role Stagnation as Determinants of Job Satisfaction and Turnover Intention in Banking Sector.

Science.gov (United States)

Kunte, Monica; Gupta, Priya; Bhattacharya, Sonali; Neelam, Netra

2017-01-01

This study examined the relationship of the organizational role stress: Role overload, role self-distance, and role stagnation with job satisfaction and turnover intention with a sample of banking employees in India. In this research, we used the RODS scale developed by Prohit and Pareek (2010) for measuring occupational role scale. The reliability of the scale came out to be 0.71. The majority of employees of all ranks, in both private and public sector banks, suffer from high role stress of all types. It was found that role overload and role stagnation are inversely associated with banking employees' job satisfaction. Private sector bank employees have more role stress and more unsatisfied than employees of public sector banks. Employees Turnover intention was found to be positively impacted by job satisfaction, contrary to many other studies. Possible reasons have been suggested. Job satisfaction was found to play a partial mediating role in the relationship between role overload and turnover intention with 40% mediation. Further, employees with longer tenure (work experience) have less role stress and are more satisfied. This study is unique in the sense there is hardly any study linking role stress to job satisfaction and turnover intention, specially in Indian context.

Comparing standardized measures of diligence and achievement with dental student academic performance.

Science.gov (United States)

Jedrychowski, Joseph; Lindemann, Robert

2005-04-01

Utilizing a reliable and valid instrument to measure a student's application of energy and effort towards a goal (diligence) or the ability to reach goals (achievement) would enable dental educators to anticipate academic performance. This knowledge could be used to better distribute faculty and educational resources, as additional tutors could be provided for students who score low on diligence and achievement instruments. In this study, fourth-year dental students completed the Diligence Inventory and the NachNaff Scale (which measures desire to achieve) immediately prior to graduation. The scores from both inventories were correlated with nine measures of academic performance. For males, the NachNaff Scale positively correlated (pDiligence mean positively correlated with EPR and National Board Parts I and II scores. For females, the Total Diligence mean positively correlated with EPR and a predental biology-chemistry-physics grade composite. Given the simplicity of the Diligence Inventory and its significant correlations with academic performance demonstrated in this study, it appears to be a useful tool to gain insight into students' diligence in striving to obtain goals.

One- and two-dimensional density and temperature measurements of an argon-neon Z-pinch plasma at stagnation

International Nuclear Information System (INIS)

Wong, K.L.; Springer, P.T.; Hammer, J.H.; Iglesias, C.A.; Osterheld, A.L.; Foord, M.E.; Bruns, H.C.; Emig, J.A.; Deeney, C.

1997-01-01

In order to benchmark and improve current 2D radiation magnetohydrodynamic (MHD) models of Z-pinch plasmas, we have performed experiments which characterize the plasma conditions at stagnation. In the experiments the SATURN pulsed power facility at Sandia National Laboratory was used to create an imploding Ar-Ne plasma. An absolutely calibrated, high resolution space- and time-resolving Johann crystal spectrometer was used to infer the electron temperature T e from the slope of the hydrogenlike Ne free-bound continuum, and the ion density n i from the Stark broadening of the Ar heliumlike Rydberg series. 2D electron temperature profiles of the plasma are obtained from a set of imaging crystals also focused on the Ne free-bound continuum. We shot two types of gas nozzles in the experiment, annular and uniform fill, which varies the amount of mass in the plasma. 2D local thermodynamic equilibrium (LTE) and non-LTE MHD models predict a radiating region denser and cooler than measured. copyright 1997 American Institute of Physics

A numerical study for off-centered stagnation flow towards a rotating disc

Directory of Open Access Journals (Sweden)

M. Heydari

2015-09-01

Full Text Available In this investigation, a semi-numerical method based on Bernstein polynomials for solving off-centered stagnation flow towards a rotating disc is introduced. This method expands the desired solutions in terms of a set of Bernstein polynomials over a closed interval and then makes use of the tau method to determine the expansion coefficients to construct approximate solutions. This method can satisfy boundary conditions at infinity. The properties of Bernstein polynomials are presented and are utilized to reduce the solution of governing nonlinear equations and their associated boundary conditions to the solution of algebraic equations. Graphical results are presented to investigate the influence of the rotation ratio α on the radial velocity, azimuthal velocity and the induced velocities. A comparative study with the previous results of viscous fluid flow in the literature is made.

Correlates of Achieving the Guidelines of Four Forms of Physical Activity, and the Relationship between Guidelines Achievement and Academic Performance: Undergraduate Students in Finland.

Science.gov (United States)

El Ansari, Walid; Suominen, Sakari; Draper, Steve

2017-06-01

We surveyed and compared, by gender, the levels and correlates of achieving the international guidelines of four forms of physical activity (PA): moderate PA (MPA), vigorous PA (VPA), moderate or vigorous PA (MVPA), and muscle strengthening PA (MSPA). The study assessed the associations between achieving the guidelines of the four PA forms and a range of socio-demographic, health and academic performance variables. Data was collected across the seven faculties of the University of Turku (2013-2014 from a representative sample of 1,189 undergraduates). An English language online self-administered questionnaire assessed frequency and duration of PA/week for each form of PA. We employed cut-offs for the guidelines in accordance with the American Heart Association. Chi-square statistic tested the differences in PA, socio-demographic variables and academic performance between males and females. Binary logistic regression examined the factors associated with achieving the four PA guidelines and linear regression examined the association between the frequency of PA and academic performance. Achievement of PA guidelines was relatively low across the sample. Female students were less likely to achieve the VPA or MSPA guidelines, but were more health conscious and in generally exhibited better academic performace than males. High health awareness and excellent/very good self-rated health were the strongest predictors of achieving all forms of PA. Parents' education level was positively related to likelihood of achieving the VPA, MVPA and MSPA guidelines. Achieving the MPA guidelines (but not VPA or MSPA) was positively associated with subjective perceptions of better academic performance. Achievement of PA guidelines was generally low for this sample of Finnish students, and was associated with positive health status and high health awareness. Universities need a holistic approach to improve awareness of health and promote PA in students' lifestyles. Copyright© by the

Prediction of intrinsic motivation and sports performance using 2 x 2 achievement goal framework.

Science.gov (United States)

Li, Chiung-Huang; Chi, Likang; Yeh, Suh-Ruu; Guo, Kwei-Bin; Ou, Cheng-Tsung; Kao, Chun-Chieh

2011-04-01

The purpose of this study was to examine the influence of 2 x 2 achievement goals on intrinsic motivation and performance in handball. Participants were 164 high school athletes. All completed the 2 x 2 Achievement Goals Questionnaire for Sport and the Intrinsic Motivation subscale of the Sport Motivation Scale; the coach for each team rated his athletes' overall sports performance. Using simultaneous-regression analyses, mastery-approach goals positively predicted both intrinsic motivation and performance in sports, whereas performance-avoidance goals negatively predicted sports performance. These results suggest that athletes who pursue task mastery and improvement of their competence perform well and enjoy their participation. In contrast, those who focus on avoiding normative incompetence perform poorly.

Melting heat transfer in boundary layer stagnation-point flow towards a stretching/shrinking sheet

International Nuclear Information System (INIS)

Bachok, Norfifah; Ishak, Anuar; Pop, Ioan

2010-01-01

An analysis is carried out to study the steady two-dimensional stagnation-point flow and heat transfer from a warm, laminar liquid flow to a melting stretching/shrinking sheet. The governing partial differential equations are converted into ordinary differential equations by similarity transformation, before being solved numerically using the Runge-Kutta-Fehlberg method. Results for the skin friction coefficient, local Nusselt number, velocity profiles as well as temperature profiles are presented for different values of the governing parameters. Effects of the melting parameter, stretching/shrinking parameter and Prandtl number on the flow and heat transfer characteristics are thoroughly examined. Different from a stretching sheet, it is found that the solutions for a shrinking sheet are non-unique.

Biological nitrate transport in sediments on the Peruvian margin mitigates benthic sulfide emissions and drives pelagic N loss during stagnation events

Science.gov (United States)

Dale, A. W.; Sommer, S.; Lomnitz, U.; Bourbonnais, A.; Wallmann, K.

2016-06-01

Benthic N cycling in the Peruvian oxygen minimum zone (OMZ) was investigated at ten stations along 12 °S from the middle shelf (74 m) to the upper slope (1024 m) using in situ flux measurements, sediment biogeochemistry and modeling. Middle shelf sediments were covered by mats of the filamentous bacteria Thioploca spp. and contained a large 'hidden' pool of nitrate that was not detectable in the porewater. This was attributed to a biological nitrate reservoir stored within the bacteria to oxidize sulfide during 'dissimilatory nitrate reduction to ammonium' (DNRA). The extremely high rates of DNRA on the shelf (15.6 mmol m-2 d-1 of N), determined using an empirical steady-state model, could easily supply all the ammonium requirements for anammox in the water column. The model further showed that denitrification by foraminifera may account for 90% of N2 production at the lower edge of the OMZ. At the time of sampling, dissolved oxygen was below detection limit down to 400 m and the water body overlying the shelf had stagnated, resulting in complete depletion of nitrate and nitrite. A decrease in the biological nitrate pool was observed on the shelf during fieldwork concomitant with a rise in porewater sulfide levels in surface sediments to 2 mM. Using a non-steady state model to simulate this natural anoxia experiment, these observations were shown to be consistent with Thioploca surviving on a dwindling intracellular nitrate reservoir to survive the stagnation period. The model shows that sediments hosting Thioploca are able to maintain high ammonium fluxes for many weeks following stagnation, potentially sustaining pelagic N loss by anammox. In contrast, sulfide emissions remain low, reducing the economic risk to the Peruvian fishery by toxic sulfide plume development.

Predicting subjective vitality and performance in sports: the role of passion and achievement goals.

Science.gov (United States)

Li, Chiung-Huang

2010-06-01

The major purpose of this study was to test the hypothesized paths from dualistic passions through achievement goals to subjective vitality and performance in sports. 645 high school athletes participated. The proposed structural equation model, with relationships between dualistic passions and subjective vitality and sports performance mediated by achievement goals, fit the data well, especially for mastery-approach and performance-approach goals. Harmonious and obsessive passions may lead athletes to high performance via the adoption of mastery-approach goals. However, these passions seem to have two paths influencing personal functioning: direct effects make players feel energetic, and indirect effects on subjective vitality through adoption of mastery-approach and performance-approach goals.

Motivation and performance within a collaborative computer-based modeling task: Relations between students' achievement goal orientation, self-efficacy, cognitive processing and achievement

OpenAIRE

Sins, P.H.M.; van Joolingen, W.R.; Savelsbergh, E.R.; van Hout-Wolters, B.H.A.M.

2008-01-01

Purpose of the present study was to test a conceptual model of relations among achievement goal orientation, self-efficacy, cognitive processing, and achievement of students working within a particular collaborative task context. The task involved a collaborative computer-based modeling task. In order to test the model, group measures of mastery-approach goal orientation, performance-avoidance goal orientation, self-efficacy, and achievement were employed. Students’ cognitive processing was a...

Predicting Examination Performance Using an Expanded Integrated Hierarchical Model of Test Emotions and Achievement Goals

Science.gov (United States)

Putwain, Dave; Deveney, Carolyn

2009-01-01

The aim of this study was to examine an expanded integrative hierarchical model of test emotions and achievement goal orientations in predicting the examination performance of undergraduate students. Achievement goals were theorised as mediating the relationship between test emotions and performance. 120 undergraduate students completed…

Role Overload, Role Self Distance, Role Stagnation as Determinants of Job Satisfaction and Turnover Intention in Banking Sector

OpenAIRE

Kunte, Monica; Gupta, Priya; Bhattacharya, Sonali; Neelam, Netra

2017-01-01

Purpose: This study examined the relationship of the organizational role stress: Role overload, role self-distance, and role stagnation with job satisfaction and turnover intention with a sample of banking employees in India. Methodology: In this research, we used the RODS scale developed by Prohit and Pareek (2010) for measuring occupational role scale. The reliability of the scale came out to be 0.71. Findings: The majority of employees of all ranks, in both private and public sector banks,...

Investigation of Three-Dimensional Axisymmetric Unsteady Stagnation-Point Flow and Heat Transfer Impinging on an Accelerated Flat Plate

OpenAIRE

ali shokrgozar abbasi; Asghar Baradaran Rahimi; Hamidreza Mozayeni

2016-01-01

General formulation and solution of Navier-Stokes and energy equations are sought in the study of threedimensional axisymmetric unsteady stagnation-point flow and heat transfer impinging on a flat plate when the plate is moving with variable velocity and acceleration towards the main stream or away from it. As an application, among others, this accelerated plate can be assumed as a solidification front which is being formed with variable velocity. An external fluid, along z - directi...

Striving for Excellence Sometimes Hinders High Achievers: Performance-Approach Goals Deplete Arithmetical Performance in Students with High Working Memory Capacity

Science.gov (United States)

Crouzevialle, Marie; Smeding, Annique; Butera, Fabrizio

2015-01-01

We tested whether the goal to attain normative superiority over other students, referred to as performance-approach goals, is particularly distractive for high-Working Memory Capacity (WMC) students—that is, those who are used to being high achievers. Indeed, WMC is positively related to high-order cognitive performance and academic success, a record of success that confers benefits on high-WMC as compared to low-WMC students. We tested whether such benefits may turn out to be a burden under performance-approach goal pursuit. Indeed, for high achievers, aiming to rise above others may represent an opportunity to reaffirm their positive status—a stake susceptible to trigger disruptive outcome concerns that interfere with task processing. Results revealed that with performance-approach goals—as compared to goals with no emphasis on social comparison—the higher the students’ WMC, the lower their performance at a complex arithmetic task (Experiment 1). Crucially, this pattern appeared to be driven by uncertainty regarding the chances to outclass others (Experiment 2). Moreover, an accessibility measure suggested the mediational role played by status-related concerns in the observed disruption of performance. We discuss why high-stake situations can paradoxically lead high-achievers to sub-optimally perform when high-order cognitive performance is at play. PMID:26407097

ACHIEVING MATURITY (AND MEASURING PERFORMANCE THROUGH MODEL-BASED PROCESS IMPROVEMENT

Directory of Open Access Journals (Sweden)

Jose Marcelo Almeida Prado Cestari

2013-08-01

Full Text Available This paper presents the approach adopted by a software development unit in order to achieve the maturity level 3 of CMMI-DEV and therefore obtaining better performance. Through historical research and secondary data analysis of the organization, the paper intends to answer the following research question: "Could the adoption of maturity/best practices models bring better performance results to small and medium organizations?" Data and analysis conducted show that, besides the creation of indicator’s based management, there are some quantitative performance improvements in indicators such as: Schedule Deviation Rate, Effort Deviation Rate, Percent Late Delivery, Productivity Deviation and Internal Rework Rate

Stagnating Jatropha Biofuel Development in Southwest China: An Institutional Approach

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Jia Li

2014-05-01

Full Text Available Biodiesel from jatropha has been considered as a promising alternative to fossil fuels for some time. Consequently, China started promoting jatropha as one of the options to meet its ever-increasing energy consumption, and the Chinese biodiesel industry also gained interest. However, the excitement of the biofuel industry in jatropha faded after it did not bring about the expected results. This article investigates the stagnation in jatropha development and production for biodiesel in China, using two detailed case studies of jatropha biofuel production in southeast China. It is found that the underdeveloped biodiesel policy and regulation, such as a rather late formulation of standards for biodiesel (especially the B5 and the absence of mandatory targets, is an important reason for hampering jatropha development. Besides that, lack of financial support undermined sustained jatropha planting at the farm level and lack of sustained commitment from state-owned enterprises or private companies over a long time span further contributed to jatropha project’s failure. Better implementation of the rule of law, mandatory blending requirements, hazard insurance, as well as continuous financial support, might improve the continuation of jatropha plantation schemes.

Cognitive performance and academic achievement: How do family and school converge?

Directory of Open Access Journals (Sweden)

Ana Filipa Alves

2017-12-01

Full Text Available Children enter the school system with different educational experiences, leaving also with different levels of learning and school results. In this study, we intend to understand the impact of family and school on children's cognitive performance and academic achievement during elementary education. The sample consists of 406 Portuguese children, from preschool and the 1st cycle of Basic Education, aged from 4 to 10 years old. Through full structural equation model, it was observed that the latent variable family (parents’ schooling and socioeconomic level and the latent variable school (community and type of school have a significant impact on academic achievement. However, only family presents a significant impact on cognitive performance. These data suggest that the impact of school on intelligence quotient is not expressive in early academic years, where family present higher explanation of the variance.

A Comparison of Low Performing Students' Achievements in Factoring Cubic Polynomials Using Three Different Strategies

Science.gov (United States)

Ogbonnaya, Ugorji I.; Mogari, David L.; Machisi, Eric

2013-01-01

In this study, repeated measures design was employed to compare low performing students' achievements in factoring cubic polynomials using three strategies. Twenty-five low-performing Grade 12 students from a secondary school in Limpopo province took part in the study. Data was collected using achievement test and was analysed using repeated…

Know thyself: misperceptions of actual performance undermine achievement motivation, future performance, and subjective well-being.

Science.gov (United States)

Kim, Young-Hoon; Chiu, Chi-Yue; Zou, Zhimin

2010-09-01

Contrary to the popular assumption that self-enhancement improves task motivation and future performance, the authors propose that both inflated and deflated self-assessments of performance are linked to an increased likelihood of practicing self-handicapping and having relatively poor performance in future tasks. Consistent with this proposal, we found that irrespective of the level of actual performance, compared with accurate self-assessment, both inflated and deflated self-assessments of task performance are associated with a greater tendency to (a) practice self-handicapping (Study 1: prefer to work under distraction; Study 2: withhold preparatory effort), (b) perform relatively poorly in a subsequent task (Study 3), (c) have relatively low academic achievement (Study 4), and (d) report a relatively low level of subjective well-being (Study 5). The authors discuss these results in terms of their educational implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Assessing the performance of Dutch local energy companies

International Nuclear Information System (INIS)

Blokhuis, Erik; Advokaat, Bart; Schaefer, Wim

2012-01-01

According to binding European Union agreements, the Netherlands has to cover at least 14% of its total energy use with renewable energy sources by 2020. However, the share of renewable energy in the Netherlands is small and hardly increasing. In 2010, renewable energy in the Netherlands accounted for only 3.8% of the national energy use, and has decreased with 0.4% compared to 2009. A cause of the stagnating renewable energy generation in the Netherlands is the absence of a nation-wide, clear and consistent long-term policy on the introduction of renewable energy. In order to overcome the current standstill in renewable energy adoption, several Dutch municipalities take the initiative and establish Local Energy Companies (LECs). However, to date, it is unclear which LEC type performs best. This research aims to compare the performance of existing LECs on three aspects: technology, finance, and organization. Furthermore, the performance of existing LECs is compared with theoretical reference LECs, in order to estimate efficiencies and opportunities for improvements. Finally, the influence of the recent changes in the Dutch subsidy scheme on LEC performance is examined. In order to achieve these aims, the benchmark method Data Envelopment Analysis is employed. - Highlights: ► Dutch Local Energy Companies (LECs) producing heat perform best in cost efficiency. ► Technical efficiency is highest in Dutch Local Energy Companies employing wind energy. ► Theoretical assumptions concerning LEC performance are not yet achieved in practice. ► The self supply model adds to the profitability of LECs, independent from subsidies. ► Recent changes in Dutch subsidy schemes add little to LECs’ financial performance.

THERMOSS: a thermohydraulic model of flow stagnation in a horizontal fuel channel

International Nuclear Information System (INIS)

Gulshani, P.; Caplan, M.Z.; Spinks, N.J.

1984-01-01

Following a postulated inlet-side small break in the CANDU reactor, emergency coolant is injected to refull the horizontal fuel channels and remove the decay heat. As part of the accident analysis, the effects of loss of forced circulation during the accident are predicted. A break size exists for which, at the end of pump rundown, the break force balances the natural circulation force and the channel flow is reduced to near zero. The subcooled, stagnant channel condition is referred to as the standing-start condition. Subsequently, the channel coolant boils and stratifies. Eventually the steam flow from the channel heats up the endfitting to the saturation temperature and reaches the vertical feeder. The resulting buoyancy-induced flow then refills the channel. One dimensional, two-fluid conservation equations are solved in closed form to predict the duration of stagnation. In this calculation the channel water level is an important intermediate variable because it determines the amount of steam production

Categorization of flow conditions using Integral quantities for characterizing stagnation and recirculation

International Nuclear Information System (INIS)

Han, M.H.; Hwang, W.T.; Jeong, H.J.; Kim, E.H.

2008-01-01

This paper describes a method for categorizing an atmospheric flow condition of a site by using integral quantities for characterizing stagnation and recirculation. Authors have devised a method for categorizing flow conditions using distribution curves which represent the flow condition of the whole of Korea. It was found that the flow conditions for four nuclear power plant sites were good enough from a meteorological aspect. Among the four sites, Kori nuclear power plant site which is located at the south-eastern part of the Korean peninsular shows the best condition. Meteorological condition is the key factor for estimating the environmental effects of a nuclear facility. The devised method can be used for assessing the relative environmental risk of a nuclear facility with only meteorological data. And the devised categorization method can be used for choosing a suitable site for an industrial facility such as a nuclear power plant and a chemical complex. (author)

Self-Generated Magnetic Fields in Stagnation-Phase ICF Implosions

Science.gov (United States)

Walsh, Christopher; Chittenden, Jeremy; McGlinchey, Kristopher; Niasse, Nicolas

2016-10-01

3-D extended-MHD simulations of the stagnation phase of an ICF implosion are presented, showing significant self-generated magnetic fields (1000-5000T) due to the Biermann Battery effect. Perturbed hot-spots generate magnetic fields at their edges, as the extremities of hot bubbles are rapidly cooled by the surrounding low temperature fuel, giving non-parallel electron pressure and density gradients. Larger amplitude and higher mode-number perturbations lead to an increased hot-spot surface area and more heat flow, developing greater non-parallel gradients and therefore larger magnetic fields. Due to this, largely perturbed hot-spots can be affected more by magnetic fields, although the accelerated cooling associated with greater deviations from symmetry lowers magnetisation. The Nernst effect advects magnetic field down temperature gradients towards the outer region of the hot-spot, which can also lower the magnetisation of the plasma. In some regions, however, the Nernst velocity is convergent, magnetising the tips of cold fuel spikes, resulting in anisotropic heat-flow and an improvement in energy containment. Low-mode and multi-high-mode simulations are shown, with magnetisations reaching sufficiently high levels in some regions of the hot-spot to suppress thermal conduction to lower than 50% of the unmagnetised case. A quantitative analysis of how this affects the hot-spot energy balance is included.

How to Achieve Quality Business Performance in an Organization

Directory of Open Access Journals (Sweden)

Merima Bekri ć

2013-02-01

Full Text Available RQ: The research question is the influence of quality management on quality business performance.Purpose: Determine which top management approaches are essential for business excellence and leadership approaches that achieve quality business.Method: Analysis of articles from the Journal Organization from the last 5 years and one article from the Journal of Universal Excellent to obtain data.Results: Characteristics of managers and individual employees influence the quality of an organization's performance and business excellence. This is rudimentary for an organization to perform successfully. The results show the weaknesses that an organization can improve in.Organization: The research study facilitates in improving long-term success of an organization. The results can assist in further decision-making and timely responses to changes in its internal and external environment.Society: Better business performance contributes to the wider environment, as this also ensures stability of an organization.Originality: A different approach in viewing management issuesand searching for improvements. There are not many review articles on this topic.Limitations: The analysis was conducted with only ten articles.

Minimising the risk of water hammer and other problems at the beginning of stagnation of solar thermal plants - A theoretical approach

International Nuclear Information System (INIS)

Streicher, W.

2000-01-01

Solar plants are increasingly used not only for hot tap water heating but also for the assistance of space heating. These plants produce much more energy in summer than needed, which often results in stagnation. Because of stagnation-temperatures of todays selective collectors up to 200 deg. C, the collector fluid evaporates. In several plants a high noise level and a vibration of the plant during this evaporation phase is reported. This is due to the occurrence of water hammers in the system, when liquid collector fluid passes areas where the fluid was already evaporated and superheated. The remaining vapor bubbles deflate rapidly and the liquid phases collide with high velocity, which results in a rapid pressure increase. This paper describes the theory of condensate-induced water hammers and conditions of solar plants, under which this can happen. A simulation model for the evaporation phase of the collector is presented to give a deeper understanding about the influences of solar radiation, the size of the tubing, and the size of the expansion device on the process of the evaporation. Three hydraulic layouts of the collector area are discussed for there possibilities producing water hammers. (au)

How to achieve and prove performance improvement - 15 years of experience in German wastewater benchmarking.

Science.gov (United States)

Bertzbach, F; Franz, T; Möller, K

2012-01-01

This paper shows the results of performance improvement, which have been achieved in benchmarking projects in the wastewater industry in Germany over the last 15 years. A huge number of changes in operational practice and also in achieved annual savings can be shown, induced in particular by benchmarking at process level. Investigation of this question produces some general findings for the inclusion of performance improvement in a benchmarking project and for the communication of its results. Thus, we elaborate on the concept of benchmarking at both utility and process level, which is still a necessary distinction for the integration of performance improvement into our benchmarking approach. To achieve performance improvement via benchmarking it should be made quite clear that this outcome depends, on one hand, on a well conducted benchmarking programme and, on the other, on the individual situation within each participating utility.

Daily online testing in large classes: boosting college performance while reducing achievement gaps.

Directory of Open Access Journals (Sweden)

James W Pennebaker

Full Text Available An in-class computer-based system, that included daily online testing, was introduced to two large university classes. We examined subsequent improvements in academic performance and reductions in the achievement gaps between lower- and upper-middle class students in academic performance. Students (N = 901 brought laptop computers to classes and took daily quizzes that provided immediate and personalized feedback. Student performance was compared with the same data for traditional classes taught previously by the same instructors (N = 935. Exam performance was approximately half a letter grade above previous semesters, based on comparisons of identical questions asked from earlier years. Students in the experimental classes performed better in other classes, both in the semester they took the course and in subsequent semester classes. The new system resulted in a 50% reduction in the achievement gap as measured by grades among students of different social classes. These findings suggest that frequent consequential quizzing should be used routinely in large lecture courses to improve performance in class and in other concurrent and subsequent courses.

Advection-diffusion model for normal grain growth and the stagnation of normal grain growth in thin films

International Nuclear Information System (INIS)

Lou, C.

2002-01-01

An advection-diffusion model has been set up to describe normal grain growth. In this model grains are divided into different groups according to their topological classes (number of sides of a grain). Topological transformations are modelled by advective and diffusive flows governed by advective and diffusive coefficients respectively, which are assumed to be proportional to topological classes. The ordinary differential equations governing self-similar time-independent grain size distribution can be derived analytically from continuity equations. It is proved that the time-independent distributions obtained by solving the ordinary differential equations have the same form as the time-dependent distributions obtained by solving the continuity equations. The advection-diffusion model is extended to describe the stagnation of normal grain growth in thin films. Grain boundary grooving prevents grain boundaries from moving, and the correlation between neighbouring grains accelerates the stagnation of normal grain growth. After introducing grain boundary grooving and the correlation between neighbouring grains into the model, the grain size distribution is close to a lognormal distribution, which is usually found in experiments. A vertex computer simulation of normal grain growth has also been carried out to make a cross comparison with the advection-diffusion model. The result from the simulation did not verify the assumption that the advective and diffusive coefficients are proportional to topological classes. Instead, we have observed that topological transformations usually occur on certain topological classes. This suggests that the advection-diffusion model can be improved by making a more realistic assumption on topological transformations. (author)

Achieving the optimal performance of the CMS ECAL in Run II

CERN Document Server

Sun, Menglei

2016-01-01

Many physics analyses using the Compact Muon Solenoid (CMS) detector at the LHC require accurate, high resolution electron and photon energy measurements. Particularly important are decays of the Higgs boson resulting in electromagnetic particles in the final state. Di-photon events in CMS are also a very important channel in the search for Higgs boson production in association with other particles or in the search for possible new resonances of higher mass. The requirement for high performance electromagnetic calorimetry therefore remains high during LHC Run II. Following the excellent performance achieved in Run~I at a center of mass energy of 7 and 8 TeV, the CMS electromagnetic calorimeter (ECAL) started operating at the LHC in Spring 2015 with proton-proton collisions at 13 TeV center-of-mass energy. The instantaneous luminosity delivered by the LHC during Run~II is expected to exceed the levels achieved in Run I, using 25 ns bunch spacing. The average number of concurrent proton-proton collisions per bu...

Performance-based alternative assessments as a means of eliminating gender achievement differences on science tests

Science.gov (United States)

Brown, Norman Merrill

1998-09-01

Historically, researchers have reported an achievement difference between females and males on standardized science tests. These differences have been reported to be based upon science knowledge, abstract reasoning skills, mathematical abilities, and cultural and social phenomena. This research was designed to determine how mastery of specific science content from public school curricula might be evaluated with performance-based assessment models, without producing gender achievement differences. The assessment instruments used were Harcourt Brace Educational Measurement's GOALSsp°ler: A Performance-Based Measure of Achievement and the performance-based portion of the Stanford Achievement Testspcopyright, Ninth Edition. The identified independent variables were test, gender, ethnicity, and grade level. A 2 x 2 x 6 x 12 (test x gender x ethnicity x grade) factorial experimental design was used to organize the data. A stratified random sample (N = 2400) was selected from a national pool of norming data: N = 1200 from the GOALSsp°ler group and N = 1200 from the SAT9spcopyright group. The ANOVA analysis yielded mixed results. The factors of test, gender, ethnicity by grade, gender by grade, and gender by grade by ethnicity failed to produce significant results (alpha = 0.05). The factors yielding significant results were ethnicity, grade, and ethnicity by grade. Therefore, no significant differences were found between female and male achievement on these performance-based assessments.

Boredom in Achievement Settings: Exploring Control-Value Antecedents and Performance Outcomes of a Neglected Emotion

Science.gov (United States)

Pekrun, Reinhard; Goetz, Thomas; Daniels, Lia M.; Stupnisky, Robert H.; Perry, Raymond P.

2010-01-01

The linkages of achievement-related boredom with students' appraisals and performance outcomes were examined in a series of 5 exploratory, cross-sectional, and predictive investigations. Studies 1 and 2 assessed students' boredom in a single achievement episode (i.e., state achievement boredom); Studies 3, 4, and 5 focused on their habitual…

Relationship of Mathematics Olympiad Performance of Gifted Students with IQ and Mathematics Achievement

Directory of Open Access Journals (Sweden)

Ali İhsan BORAN

2015-04-01

Full Text Available The purpose of this study is to investigate relationship of mathematics Olympiad (analysis-algebra and geometry scores of gifted students with IQ scores (verbal, performance and general and mathematics achievement scores of the gifted students. Study group of the study included 64 gifted students (27 girls and 37 boys who took courses from one Science and Art Center. Data of study involved scores of the participants on mathematics Olympiad exam, WISC-R test and school mathematics achievement. For analysis of the data Pearson correlation analysis, Spearman correlation analysis, independent groups’ t-test and Mann Whitney U test were utilized. The findings showed that there was no significant relationship between the Olympiad scores on analysis-algebra and geometry and IQ scores (general, performance and verbal. But the Olympiad scores on analysis-algebra and geometry factors were significantly related to school mathematics achievement. Comparing IQ scores of highest and lowest scorer groups on the Olympiad scores showed that there were no significant differences between IQ scores (general, performance and verbal of the groups. However school mathematics scores of the participants significantly differed in terms of groups determined based on analysis-algebra and geometry scores.

Secondary Students' Writing Achievement Goals: Assessing the Mediating Effects of Mastery and Performance Goals on Writing Self-Efficacy, Affect, and Writing Achievement

Science.gov (United States)

Yilmaz Soylu, Meryem; Zeleny, Mary G.; Zhao, Ruomeng; Bruning, Roger H.; Dempsey, Michael S.; Kauffman, Douglas F.

2017-01-01

The two studies reported here explored the factor structure of the newly constructed Writing Achievement Goal Scale (WAGS), and examined relationships among secondary students' writing achievement goals, writing self-efficacy, affect for writing, and writing achievement. In the first study, 697 middle school students completed the WAGS. A confirmatory factor analysis revealed a good fit for this data with a three-factor model that corresponds with mastery, performance approach, and performance avoidance goals. The results of Study 1 were an indication for the researchers to move forward with Study 2, which included 563 high school students. The secondary students completed the WAGS, as well as the Self-efficacy for Writing Scale, and the Liking Writing Scale. Students also self-reported grades for writing and for language arts courses. Approximately 6 weeks later, students completed a statewide writing assessment. We tested a theoretical model representing relationships among Study 2 variables using structural equation modeling including students' responses to the study scales and students' scores on the statewide assessment. Results from Study 2 revealed a good fit between a model depicting proposed relationships among the constructs and the data. Findings are discussed relative to achievement goal theory and writing. PMID:28878707

MHD stagnation point flow by a permeable stretching cylinder with Soret-Dufour effects

Institute of Scientific and Technical Information of China (English)

M Ramzan; M Farooq; T Hayat; A Alsaedi; J Cao

2015-01-01

Combined effects of Soret (thermal-diffusion) and Dufour (diffusion-thermo) in MHD stagnation point flow by a permeable stretching cylinder were studied. Analysis was examined in the presence of heat generation/absorption and chemical reaction. The laws of conservation of mass, momentum, energy and concentration are found to lead to the mathematical development of the problem. Suitable transformations were used to convert the nonlinear partial differential equations into the ordinary differential equations. The series solutions of boundary layer equations through momentum, energy and concentration equations were obtained. Convergence of the developed series solutions was discussed via plots and numerical values. The behaviors of different physical parameters on the velocity components, temperature and concentration were obtained. Numerical values of Nusselt number, skin friction and Sherwood number with different parameters were computed and analyzed. It is found that Dufour and Soret numbers result in the enhancement of temperature and concentration distributions, respectively.

The Effects of the Classroom Performance System on Student Participation, Attendance, and Achievement

Science.gov (United States)

Termos, Mohamad Hani

2013-01-01

The Classroom Performance System (CPS) is an instructional technology that increases student performance and promotes active learning. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes, where students' first spoken language is not English.…

Proton imaging of hohlraum plasma stagnation in inertial-confinement-fusion experiments

International Nuclear Information System (INIS)

Li, C.K.; Séguin, F.H.; Frenje, J.A.; Sinenian, N.; Rosenberg, M.J.; Manuel, M.J.-E; Rinderknecht, H.G.; Zylstra, A.B.; Petrasso, R.D.; Amendt, P.A.; Landen, O.L.; Mackinnon, A.J.; Town, R.P.J.; Wilks, S.C.; Betti, R.; Meyerhofer, D.D.; Soures, J.M.; Hund, J.; Kilkenny, J.D.; Nikroo, A.

2013-01-01

Proton radiography of the spatial structure and temporal evolution of plasma blowing off from a hohlraum wall reveals how the fill gas compresses the wall blow-off, inhibits plasma jet formation and impedes plasma stagnation in the hohlraum interior. The roles of spontaneously generated electric and magnetic fields in hohlraum dynamics and capsule implosions are demonstrated. The heat flux is shown to rapidly convect the magnetic field due to the Nernst effect, which is shown to be ∼10 times faster than convection by the plasma fluid from expanded wall blow-off (v N ∼ 10v). This leads to inhibition of heat transfer from the gas region in the laser beam paths to the surrounding cold gas, resulting in a local plasma temperature increase. The experiments show that interpenetration of the two materials (gas and wall) occurs due to the classical Rayleigh–Taylor instability as the lighter, decelerating ionized fill gas pushes against the heavier, expanding gold wall blow-off. This experiment provides physics insight into the effects of fill gas on x-ray-driven implosions, and would impact the ongoing ignition experiments at the National Ignition Facility. (paper)

Thermophysical analysis for three-dimensional MHD stagnation-point flow of nano-material influenced by an exponential stretching surface

Science.gov (United States)

Ur Rehman, Fiaz; Nadeem, Sohail; Ur Rehman, Hafeez; Ul Haq, Rizwan

2018-03-01

In the present paper a theoretical investigation is performed to analyze heat and mass transport enhancement of water-based nanofluid for three dimensional (3D) MHD stagnation-point flow caused by an exponentially stretched surface. Water is considered as a base fluid. There are three (3) types of nanoparticles considered in this study namely, CuO (Copper oxide), Fe3O4 (Magnetite), and Al2O3 (Alumina) are considered along with water. In this problem we invoked the boundary layer phenomena and suitable similarity transformation, as a result our three dimensional non-linear equations of describing current problem are transmuted into nonlinear and non-homogeneous differential equations involving ordinary derivatives. We solved the final equations by applying homotopy analysis technique. Influential outcomes of aggressing parameters involved in this study, effecting profiles of temperature field and velocity are explained in detail. Graphical results of involved parameters appearing in considered nanofluid are presented separately. It is worth mentioning that Skin-friction along x and y-direction is maximum for Copper oxide-water nanofluid and minimum for Alumina-water nanofluid. Result for local Nusselt number is maximum for Copper oxide-water nanofluid and is minimum for magnetite-water nanofluid.

Corporate Governance as a Crucial Factor in Achieving Sustainable Corporate Performance

Directory of Open Access Journals (Sweden)

Julija Bistrova

2014-06-01

Full Text Available In the developed stock markets the corporate governance aspect is crucial in the stock portfolio selection process for investor seeking to achieve shareholder value sustainability. In the emerging markets the importance of the corporate governance role just starts to be realized by the investors and by the corporate managers. The present research, looking at the stock performance leaders and laggards, analyzes whether the corporate governance system matters to achieve long-term shareholder value within the Central and Eastern European stock markets universe. Corporate governance quality was assessed and compared among the out- and underperformers. The financial results plausibility and the ownership structure were considered as well. Additionally, the authors analyzed whether the quality of corporate governance influences the economic performance of the company. The obtained results provide the proof that the corporate governance does matter as the market outperformers have above average corporate governance quality and provide trustworthy financial results more often than the underperforming companies. Besides, well-governed companies are also able to deliver more attractive financial results.

Secondary Students' Writing Achievement Goals: Assessing the Mediating Effects of Mastery and Performance Goals on Writing Self-Efficacy, Affect, and Writing Achievement

Directory of Open Access Journals (Sweden)

Meryem Yilmaz Soylu

2017-08-01

Full Text Available The two studies reported here explored the factor structure of the newly constructed Writing Achievement Goal Scale (WAGS, and examined relationships among secondary students' writing achievement goals, writing self-efficacy, affect for writing, and writing achievement. In the first study, 697 middle school students completed the WAGS. A confirmatory factor analysis revealed a good fit for this data with a three-factor model that corresponds with mastery, performance approach, and performance avoidance goals. The results of Study 1 were an indication for the researchers to move forward with Study 2, which included 563 high school students. The secondary students completed the WAGS, as well as the Self-efficacy for Writing Scale, and the Liking Writing Scale. Students also self-reported grades for writing and for language arts courses. Approximately 6 weeks later, students completed a statewide writing assessment. We tested a theoretical model representing relationships among Study 2 variables using structural equation modeling including students' responses to the study scales and students' scores on the statewide assessment. Results from Study 2 revealed a good fit between a model depicting proposed relationships among the constructs and the data. Findings are discussed relative to achievement goal theory and writing.

Medicare Accountable Care Organizations of Diverse Structures Achieve Comparable Quality and Cost Performance.

Science.gov (United States)

Comfort, Leeann N; Shortell, Stephen M; Rodriguez, Hector P; Colla, Carrie H

2018-01-31

To examine whether an empirically derived taxonomy of Accountable Care Organizations (ACOs) is associated with quality and spending performance among patients of ACOs in the Medicare Shared Savings Program (MSSP). Three waves of the National Survey of ACOs and corresponding publicly available Centers for Medicare & Medicaid Services performance data for NSACO respondents participating in the MSSP (N = 204); SK&A Office Based Physicians Database from QuintilesIMS. We compare the performance of three ACO types (physician-led, integrated, and hybrid) for three domains: quality, spending, and likelihood of achieving savings. Sources of performance variation within and between ACO types are compared for each performance measure. There is greater heterogeneity within ACO types than between ACO types. There were no consistent differences in quality by ACO type, nor were there differences in likelihood of achieving savings or overall spending per-person-year. There was evidence for higher spending on physician services for physician-led ACOs. ACOs of diverse structures perform comparably on core MSSP quality and spending measures. CMS should maintain its flexibility and continue to support participation of diverse ACOs. Future research to identify modifiable organizational factors that account for performance variation within ACO types may provide insight as to how best to improve ACO performance based on organizational structure and ownership. © Health Research and Educational Trust.

The Best Achievable ℋ2 Tracking Performances for SIMO Feedback Control Systems

Directory of Open Access Journals (Sweden)

Shinji Hara

2007-01-01

Full Text Available This paper is concerned with the inherent ℋ2 tracking performance limitation of single-input and multiple-output (SIMO linear time-invariant (LTI feedback control systems. The performance is measured by the tracking error between a step reference input and the plant output with additional penalty on control input. We employ the plant augmentation strategy, which enables us to derive analytical closed-form expressions of the best achievable performance not only for discrete-time system, but also for continuous-time system by exploiting the delta domain version of the expressions.

Commissioning of Japanese x-ray free electron laser, SACLA and achieved laser performance

International Nuclear Information System (INIS)

Tanaka, Hitoshi; Amselem, Arnaud; Aoyagi, Hideki

2012-01-01

After 8 months of beam commissioning of SPring-8 Angstrom Compact free electron LAser, SACLA reached the primary target performance, i.e., a shortest laser wavelength of ∼0.6 Angstrom and a laser pulse energy value of sub-mJ at a wavelength of 1.2 Angstrom. This success was due to the following four factors; (1) performance estimation of each component of SACLA required for the target laser performance and its achievement, (2) elaboration of beam diagnostics and control systems enabling precise accelerator and undulator tuning, (3) a rational and strategic commissioning plan, (4) most adequate response to various accidental events during the beam commissioning period. This article, in order to light up the above four factors leading us to the success, starts with the features of SACLA and critical tolerance for the sub-system components, and then, explains our approach to achieve the target laser performance and how the beam commissioning of SACLA proceeded. At last, the article summarizes the present laser and operational status. (author)

Thermo-diffusion effects on MHD stagnation point flow towards a stretching sheet in a nanofluid

Directory of Open Access Journals (Sweden)

Umar Khan

2014-09-01

Full Text Available Thermodiffusion effects on stagnation point flow of a nanofluid towards a stretching surface with applied magnetic field is presented. Similarity transforms are applied to reduce the equations that govern the flow to a system of nonlinear ordinary differential equations. Runge-Kutta-Fehlberg method is applied to solve the system. Results are compared with existing solutions that are special cases to our problem. Concrete graphical analysis is carried out to study the effects of different emerging parameters such as stretching ratio A, magnetic influence parameter M, Prandtl number Pr, Lewis number Le, Brownian motion parameter Nb, thermophoresis parameter Nt, nanofluid Lewis number Ln, modified Dufour parameter Nd and Dufour solutal number Ld coupled with comprehensive discussions. Numerical effects of local Nusselt number, local Sherwood number and nanofluid Sherwood number are also discussed.

Flame stabilization and mixing characteristics in a Stagnation Point Reverse Flow combustor

Science.gov (United States)

Bobba, Mohan K.

A novel combustor design, referred to as the Stagnation Point Reverse-Flow (SPRF) combustor, was recently developed that is able to operate stably at very lean fuel-air mixtures and with low NOx emissions even when the fuel and air are not premixed before entering the combustor. The primary objective of this work is to elucidate the underlying physics behind the excellent stability and emissions performance of the SPRF combustor. The approach is to experimentally characterize velocities, species mixing, heat release and flame structure in an atmospheric pressure SPRF combustor with the help of various optical diagnostic techniques: OH PLIF, chemiluminescence imaging, PIV and Spontaneous Raman Scattering. Results indicate that the combustor is primarily stabilized in a region downstream of the injector that is characterized by low average velocities and high turbulence levels; this is also the region where most of the heat release occurs. High turbulence levels in the shear layer lead to increased product entrainment levels, elevating the reaction rates and thereby enhancing the combustor stability. The effect of product entrainment on chemical timescales and the flame structure is illustrated with simple reactor models. Although reactants are found to burn in a highly preheated (1300 K) and turbulent environment due to mixing with hot product gases, the residence times are sufficiently long compared to the ignition timescales such that the reactants do not autoignite. Turbulent flame structure analysis indicates that the flame is primarily in the thin reaction zones regime throughout the combustor, and it tends to become more flamelet like with increasing distance from the injector. Fuel-air mixing measurements in case of non-premixed operation indicate that the fuel is shielded from hot products until it is fully mixed with air, providing nearly premixed performance without the safety issues associated with premixing. The reduction in NOx emissions in the SPRF

School Achievement and Performance in Chilean High Schools: The Mediating Role of Subjective Wellbeing in School-Related Evaluations

Science.gov (United States)

López, Verónica; Oyanedel, Juan C.; Bilbao, Marian; Torres, Javier; Oyarzún, Denise; Morales, Macarena; Ascorra, Paula; Carrasco, Claudia

2017-01-01

School achievement gaps and school failure are problematic issues in Latin America, and are mainly explained by the socio-economic status (SES) of the students. What schools can do to improve school achievement and reduce school failure is a critical issue, both for school management and teacher training. In this study, we present the association of individual and school-related socio-emotional variables with school achievement and performance, controlling for the effects of SES. A probabilistic sample of 4,964 students, drawn from 191 schools enrolled in year 10 in urban areas of Chile, answered questionnaires assessing subjective wellbeing, social wellbeing in school, school climate, school social wellbeing and students’ perceptions of teachers’ wellbeing. Using structural equation modeling, and controlling for SES, we modeled subjective wellbeing as a mediator of the relationship between school-related variables, such as school climate and perception of teacher’s wellbeing, and (a) school achievement, and (b) school performance. School achievement was computed as a product of (a) the probability of passing the school year, and (b) the percentage of yearly attendance at school. Data on school achievement was drawn from administrative registries from the Chilean Ministry of Education. School performance was computed as the estimated grade point average (GPA) at the end of the school year, based on the students’ previous 5-year GPAs, and was also obtained through administrative data of the last 5 years. Findings reveal the mediating role of subjective wellbeing in the relationship between school-related evaluations (students’ social wellbeing at school, their perception of teachers’ wellbeing and school climate) and school achievement. For school achievement, two variables were mediated (students’ social wellbeing at school and school climate). However, for school performance, no significant mediations were found. We conclude that, on the one hand

School Achievement and Performance in Chilean High Schools: The Mediating Role of Subjective Wellbeing in School-Related Evaluations.

Science.gov (United States)

López, Verónica; Oyanedel, Juan C; Bilbao, Marian; Torres, Javier; Oyarzún, Denise; Morales, Macarena; Ascorra, Paula; Carrasco, Claudia

2017-01-01

School achievement gaps and school failure are problematic issues in Latin America, and are mainly explained by the socio-economic status (SES) of the students. What schools can do to improve school achievement and reduce school failure is a critical issue, both for school management and teacher training. In this study, we present the association of individual and school-related socio-emotional variables with school achievement and performance, controlling for the effects of SES. A probabilistic sample of 4,964 students, drawn from 191 schools enrolled in year 10 in urban areas of Chile, answered questionnaires assessing subjective wellbeing, social wellbeing in school, school climate, school social wellbeing and students' perceptions of teachers' wellbeing. Using structural equation modeling, and controlling for SES, we modeled subjective wellbeing as a mediator of the relationship between school-related variables, such as school climate and perception of teacher's wellbeing, and (a) school achievement, and (b) school performance. School achievement was computed as a product of (a) the probability of passing the school year, and (b) the percentage of yearly attendance at school. Data on school achievement was drawn from administrative registries from the Chilean Ministry of Education. School performance was computed as the estimated grade point average (GPA) at the end of the school year, based on the students' previous 5-year GPAs, and was also obtained through administrative data of the last 5 years. Findings reveal the mediating role of subjective wellbeing in the relationship between school-related evaluations (students' social wellbeing at school, their perception of teachers' wellbeing and school climate) and school achievement. For school achievement, two variables were mediated (students' social wellbeing at school and school climate). However, for school performance, no significant mediations were found. We conclude that, on the one hand, after

The effect of authentic leadership, organizational justice, and achievement motivation on teachers' performance in vocational high school seventeen Temanggung

Science.gov (United States)

Sugi, Slamet, Achmad; Martono, S.

2018-03-01

Teachers' performance in Temanggung in 2016 did not show maximal result. It was shown from many indicators. The low score of UN, UKG and PKB result. Individual performance was different. Achievement motivation could be seen through their attitude and behavior performances. The purpose of this research is to know the effect of authentic leadership, organizational justice, and achievement motivation on teachers' performance. The objects of this research are authentic leadership, organizational justice, achievement motivation and teachers' performance in Vocational High School Seventeen in Temanggung. The research method used is quantitative. Data collection was done by questioners. Then, the data were analyzed by using Path SPSS 16. The result of this research showed that authentic leadership, organizational justice, achievement motivation had significant effect on teachers' performance in Vocational High School Seventeen in Temanggung.

The effects of training and competition on achievement goals, motivational responses, and performance in a golf-putting task

NARCIS (Netherlands)

Pol, P.K.C. van de; Kavussanu, M.; Ring, C.

2012-01-01

This study examined whether (a) training and competition influence achievement goals, effort, enjoyment, tension, and performance; (b) achievement goals mediate the effects of training and competition on effort, enjoyment, tension, and performance; and (c) the context influences the relationships

Association between scores in high school, aptitude and achievement exams and early performance in health science college

Directory of Open Access Journals (Sweden)

Al-Alwan Ibrahim

2009-01-01

Full Text Available This retrospective study was carried out to assess the correlation between admi-ssion criteria to health science colleges, namely, final high school grade and Saudi National Apti-tude and Achievement exams, and early academic performance in these colleges. The study inclu-ded 91 male students studying in the two-year pre-professional program at the King Saud bin Abdulaziz University for Health Sciences (KSAU-HS, Riyadh, Saudi Arabia. Records of these students were used to extract relevant information and their academic performance (based on the grade point average achieved at the end of the first semester of the pre-professional program, which were analytically studied. Pearson correlation coefficient was used to assess the associa-tions between the different scores. SPSS statistical program (version 12.0 was used for data ana-lyses. We found a strong correlation between the academic performance and the Achievement Exam, Aptitude Exam and high school final grade, with Pearson Correlation Coefficients of 0.96, 0.93, 0.87, respectively. The Saudi National Achievement Exam showed the most significant correla-tion. Our results indicate that academic performance showed good correlation with the admission criteria used, namely final high school grade, Saudi National Aptitude and Achievement Exams.

To master or perform? Exploring relations between achievement goals and conceptual change learning.

Science.gov (United States)

Ranellucci, John; Muis, Krista R; Duffy, Melissa; Wang, Xihui; Sampasivam, Lavanya; Franco, Gina M

2013-09-01

Research is needed to explore conceptual change in relation to achievement goal orientations and depth of processing. To address this need, we examined relations between achievement goals, use of deep versus shallow processing strategies, and conceptual change learning using a think-aloud protocol. Seventy-three undergraduate students were assessed on their prior knowledge and misconceptions about Newtonian mechanics, and then reported their achievement goals and participated in think-aloud protocols while reading Newtonian physics texts. A mastery-approach goal orientation positively predicted deep processing strategies, shallow processing strategies, and conceptual change. In contrast, a performance-approach goal orientation did not predict either of the processing strategies, but negatively predicted conceptual change. A performance-avoidance goal orientation negatively predicted deep processing strategies and conceptual change. Moreover, deep and shallow processing strategies positively predicted conceptual change as well as recall. Finally, both deep and shallow processing strategies mediated relations between mastery-approach goals and conceptual change. Results provide some support for Dole and Sinatra's (1998) Cognitive Reconstruction of Knowledge Model of conceptual change but also challenge specific facets with regard to the role of depth of processing in conceptual change. © 2012 The British Psychological Society.

A vortex ring interacting with a vortex filament and its deformation near the two-dimensional stagnation point

International Nuclear Information System (INIS)

Kiya, M.; Sato, T.

1986-01-01

In this paper the interaction between vortex filaments and vortex rings and the deformation of vortex rings near the two-dimensional stagnation point are simulated by a three-dimensional vortex method. The two problems are respectively concerned with the effect of free-stream turbulence on turbulent plane mixing layers and the production of turbulence by the vortex stretching near saddles associated with large-scale coherent structures. The authors assume that the first step to understand the free-stream turbulence effect is to study the interaction between a vortex ring and a vortex filament and that the process of deformation of a vortex ring gives us a clue to understand physical processes occurring near the saddles

School Achievement and Performance in Chilean High Schools: The Mediating Role of Subjective Wellbeing in School-Related Evaluations

Directory of Open Access Journals (Sweden)

Verónica López

2017-07-01

Full Text Available School achievement gaps and school failure are problematic issues in Latin America, and are mainly explained by the socio-economic status (SES of the students. What schools can do to improve school achievement and reduce school failure is a critical issue, both for school management and teacher training. In this study, we present the association of individual and school-related socio-emotional variables with school achievement and performance, controlling for the effects of SES. A probabilistic sample of 4,964 students, drawn from 191 schools enrolled in year 10 in urban areas of Chile, answered questionnaires assessing subjective wellbeing, social wellbeing in school, school climate, school social wellbeing and students’ perceptions of teachers’ wellbeing. Using structural equation modeling, and controlling for SES, we modeled subjective wellbeing as a mediator of the relationship between school-related variables, such as school climate and perception of teacher’s wellbeing, and (a school achievement, and (b school performance. School achievement was computed as a product of (a the probability of passing the school year, and (b the percentage of yearly attendance at school. Data on school achievement was drawn from administrative registries from the Chilean Ministry of Education. School performance was computed as the estimated grade point average (GPA at the end of the school year, based on the students’ previous 5-year GPAs, and was also obtained through administrative data of the last 5 years. Findings reveal the mediating role of subjective wellbeing in the relationship between school-related evaluations (students’ social wellbeing at school, their perception of teachers’ wellbeing and school climate and school achievement. For school achievement, two variables were mediated (students’ social wellbeing at school and school climate. However, for school performance, no significant mediations were found. We conclude that, on the

Melting heat transfer in stagnation point flow of carbon nanotubes towards variable thickness surface

Directory of Open Access Journals (Sweden)

T. Hayat

2016-01-01

Full Text Available This work concentrates on the mathematical modeling for stagnation point flow of nanofluids over an impermeable stretching sheet with variable thickness. Carbon nanotubes [single-wall carbon nanotubes (SWCNTs and multi-wall carbon nanotubes (MWCNTs] as the nanoparticles are utilized. Water and kerosene oil are taken as the base fluids. Heat transfer through melting effect is discussed. Transformation procedure is adapted to obtain the non-linear ordinary differential equations from the fundamental laws of mass, linear momentum and energy. The optimal values of convergence control parameters and corresponding individual and total residual errors for SWCNTs and MWCNTs are computed by means of homotopy analysis method (HAM based BVPh 2.0. Characteristics of different involved parameters on the velocity, temperature, skin friction coefficient and Nusselt number are discussed. Higher velocity profile is observed for wall thickness parameter in case of water carbon nanotubes when compared with the kerosene oil carbon nanotubes.

Diagnosing the Stagnation Conditions of MagLIF Implosions Using Co and Kr dopants

Science.gov (United States)

Harding, E. C.; Hansen, S. B.; Harvey-Thompson, A. J.; Weis, M. R.; Hahn, K. D.; Gomez, M. R.; Knapp, P. F.; Slutz, S. A.; Geissel, M.; Ampleford, D. J.; Jennings, C. A.; Peterson, K.; Rochau, G. A.; Doron, R.; Stambulchik, E.; Nedostup, O.; Maron, Y.; Golovkin, I.

2017-10-01

Recent experiments on the Z-machine tested several new diagnostic techniques for investigating the stagnation conditions and the origins of the mix present in a Magnetized Liner Inertial Fusion (MagLIF) target. For the first time we have collected K-shell spectra from a low-concentration, Kr dopant placed in the gaseous D2 fuel. In addition, thin Co coatings were strategically applied to three different internal surfaces of the target in order to assess which surfaces actively contribute to the contamination of the fuel. Both imaging spectroscopy and narrow-band crystal imaging were used to identify the location of He-like Co ions. The Te and ne of the Co is inferred by fitting the He-alpha lines and the near-by Li-like satellites. The experimental measurements and the challenges associated with the analysis will be discussed. Sandia Natl Lab is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. DOE NNSA under contract DE-NA-0003525.

An automatic, stagnation point based algorithm for the delineation of Wellhead Protection Areas

Science.gov (United States)

Tosco, Tiziana; Sethi, Rajandrea; di Molfetta, Antonio

2008-07-01

Time-related capture areas are usually delineated using the backward particle tracking method, releasing circles of equally spaced particles around each well. In this way, an accurate delineation often requires both a very high number of particles and a manual capture zone encirclement. The aim of this work was to propose an Automatic Protection Area (APA) delineation algorithm, which can be coupled with any model of flow and particle tracking. The computational time is here reduced, thanks to the use of a limited number of nonequally spaced particles. The particle starting positions are determined coupling forward particle tracking from the stagnation point, and backward particle tracking from the pumping well. The pathlines are postprocessed for a completely automatic delineation of closed perimeters of time-related capture zones. The APA algorithm was tested for a two-dimensional geometry, in homogeneous and nonhomogeneous aquifers, steady state flow conditions, single and multiple wells. Results show that the APA algorithm is robust and able to automatically and accurately reconstruct protection areas with a very small number of particles, also in complex scenarios.

Identifying Achievement Goals and Their Relationship to Academic Achievement in Undergraduate Pharmacy Students

Science.gov (United States)

Sainsbury, Erica; Rose, Grenville; Smith, Lorraine

2014-01-01

Objectives. To compare the achievement goal orientations of first-year with those of third-year undergraduate Australian pharmacy students and to examine the relationship of goal orientations to academic achievement. Methods. The Achievement Goal Questionnaire was administered to first-year and third-year students during class time. Students’ grades were obtained from course coordinators. Results. More first-year students adopted performance-approach and mastery-approach goals than did third-year students. Performance-approach goals were positively correlated with academic achievement in the first year. Chinese Australian students scored the highest in adopting performance-approach goals. Vietnamese Australian students adopted mastery-avoidance goals more than other ethnicities. First-year students were more strongly performance approach goal-oriented than third-year students. Conclusion. Adopting performance-approach goals was positively correlated with academic achievement, while adopting avoidance goals was not. Ethnicity has an effect on the adoption of achievement goals and academic achievement. PMID:25258438

Can achievement emotions be used to better understand motivation, learning, and performance in medical education?

Science.gov (United States)

Artino, Anthony R; Holmboe, Eric S; Durning, Steven J

2012-01-01

In this article, we consider an emergent theory of human emotion. The overarching purpose of the article is to introduce medical education researchers to the notion of achievement emotions and provide a brief overview of how this work can inform the theory, research, and practice of medical education. First, we define achievement emotions and describe one of the leading contemporary theories of achievement emotions, control-value theory (Pekrun R. 2006. The control-value theory of achievement emotions: Assumptions, corollaries, and implications for educational research and practice. Educ Psychol Rev 18:315-341.). Next, we distinguish between different types of achievement emotions, their proximal causes, and their consequences for motivation, learning, and performance, and we discuss several implications for educational practice. Finally, we end with a call for more research on achievement emotions in medical education to facilitate our understanding of emotions and their impact on important educational outcomes.

Achievement goals and interpersonal behaviour: How mastery and performance goals shape information exchange

NARCIS (Netherlands)

Poortvliet, P.M.; Janssen, O.; Van Yperen, N.W.; Van de Vliert, E.

2007-01-01

The present research examines the impact of achievement goals on task-related information exchange. Studies 1 and 2 reveal that relative to those with mastery goals or no goal, individuals pursuing performance goals were less open in their information giving to exchange partners. Study 2 further

Making Employee Recognition a Tool for Achieving Improved Performance: Implication for Ghanaian Universities

Science.gov (United States)

Amoatemaa, Abena Serwaa; Kyeremeh, Dorcas Darkoah

2016-01-01

Many organisations are increasingly making use of employee recognition to motivate employees to achieve high performance and productivity. Research has shown that effective recognition occurs in organisations that have strong supportive culture, understand the psychology of praising employees for their good work, and apply the principles of…

Performance Monitoring and Evaluation in Botswana’s Public Service: Achievements and Challenges

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Dorothy Mpabanga

2016-03-01

Full Text Available The paper aims to explore the implementation of performance monitoring and evaluation tools used in Botswana’s public service. The paper also identifies achievements and challenges of implementing performance monitoring and evaluation system and suggests ways for improvement. This paper uses secondary data sources. The paper reveals lack of performance monitoring and evaluation skills, poor supervision, poor conditions of service and a poor work ethic as some of the factors contributing to ineffective use of performance monitoring and evaluation tools in the service. Leadership commitment and support, benchmarking reforms, training and education, developed administrative and governance structures as well as well-defined public policy and program formulation and implementation processes are some of the success factors to enhanced performance management and evaluation systems in Botswana. The paper argues for adoption of a developmental-led model in order to enhance existing performance monitoring and evaluation system that would improve implementation of government policies and programs. Botswana has been striving to excel in service delivery through performance monitoring and evaluation oriented reforms.

Performance Evaluation of Methods for Estimating Achievable Throughput on Cellular Connections

DEFF Research Database (Denmark)

Mikkelsen, Lars Møller; Højholt, Nikolaj Bove; Madsen, Tatiana Kozlova

2015-01-01

The continuous increase in always connected devices and the advance in capabilities of networks and services offered via the network is evident. The target group of most of these devices and services is users, so how users perceive the network performance is of great importance. Estimating achiev...... AT, due to its much reduced resource consumption. Based on real-life measurements of the two methods we conclude that TOPP is a good candidate to estimate AT, based on similarity in results with BTC....

Botulinum Toxin A for Oral Cavity Cancer Patients: In Microsurgical Patients BTX Injections in Major Salivary Glands Temporarily Reduce Salivary Production and the Risk of Local Complications Related to Saliva Stagnation

Directory of Open Access Journals (Sweden)

Bartolo Corradino

2012-10-01

Full Text Available In patients suffering from oral cavity cancer surgical treatment is complex because it is necessary to remove carcinoma and lymph node metastasis (through a radical unilateral or bilateral neck dissection and to reconstruct the affected area by means of free flaps. The saliva stagnation in the post-operative period is a risk factor with regard to local complications. Minor complications related to saliva stagnation (such as tissue maceration and wound dehiscence could become major complications compromising the surgery or the reconstructive outcome. In fact the formation of oro-cutaneous fistula may cause infection, failure of the free flap, or the patient’s death with carotid blow-out syndrome. Botulinum injections in the major salivary glands, four days before surgery, temporarily reduces salivation during the healing stage and thus could reduce the incidence of saliva-related complications. Forty three patients with oral cancer were treated with botulinum toxin A. The saliva quantitative measurement and the sialoscintigraphy were performed before and after infiltrations of botulinum toxin in the major salivary glands. In all cases there was a considerable, but temporary, reduction of salivary secretion. A lower rate of local complications was observed in the post-operative period. The salivary production returned to normal within two months, with minimal side effects and discomfort for the patients. The temporary inhibition of salivary secretion in the post-operative period could enable a reduction in saliva-related local complications, in the incidence of oro-cutaneous fistulas, and improve the outcome of the surgery as well as the quality of residual life in these patients.

Botulinum toxin A for oral cavity cancer patients: in microsurgical patients BTX injections in major salivary glands temporarily reduce salivary production and the risk of local complications related to saliva stagnation.

Science.gov (United States)

Corradino, Bartolo; Di Lorenzo, Sara; Moschella, Francesco

2012-10-24

In patients suffering from oral cavity cancer surgical treatment is complex because it is necessary to remove carcinoma and lymph node metastasis (through a radical unilateral or bilateral neck dissection) and to reconstruct the affected area by means of free flaps. The saliva stagnation in the post-operative period is a risk factor with regard to local complications. Minor complications related to saliva stagnation (such as tissue maceration and wound dehiscence) could become major complications compromising the surgery or the reconstructive outcome. In fact the formation of oro-cutaneous fistula may cause infection, failure of the free flap, or the patient’s death with carotid blow-out syndrome. Botulinum injections in the major salivary glands, four days before surgery, temporarily reduces salivation during the healing stage and thus could reduce the incidence of saliva-related complications. Forty three patients with oral cancer were treated with botulinum toxin A. The saliva quantitative measurement and the sialoscintigraphy were performed before and after infiltrations of botulinum toxin in the major salivary glands. In all cases there was a considerable, but temporary, reduction of salivary secretion. A lower rate of local complications was observed in the post-operative period. The salivary production returned to normal within two months, with minimal side effects and discomfort for the patients. The temporary inhibition of salivary secretion in the post-operative period could enable a reduction in saliva-related local complications, in the incidence of oro-cutaneous fistulas, and improve the outcome of the surgery as well as the quality of residual life in these patients.

2-D simulations of the implosion, collapse and stagnation of laser fusion shells

International Nuclear Information System (INIS)

Atzeni, S.; Guerrieri, A.

1989-01-01

We discuss the method, model and first results of 2-D numerical simulations of the entire history of gas-filled shells irradiated by laser pulses with long wavelength non-uniformities. Although this issue has already been addressed in connection with the design of reactor targets, or with the interpretation of experimental results, a complete, clear, and quantitative picture of the relevant phenomenology is still missing. In general, the history of a target can be divided into three phases, namely, the acceleration and inertial phase of the implosion (I;t≤t 0 ), the shock collapse and reflection (II,t 0 ≤t≤t ' 0 ) and the stagnation (t ' 0 ≤t≤t 1 ). In a previous study, we were able to study quantitatively phase I and to get some qualitative information on phase II. At t≅t 0 , however, negative area zones occurred in the mesh of our purely Lagrangian code, and the simulations became unreliable. We have now upgraded our code, by introducing an automatic mesh-rezoning package, which allows us to follow with reasonable accuracy phase II and III of the target implosion. (author) 9 refs., 6 figs

Heat transfer in boundary layer stagnation-point flow towards a shrinking sheet with non-uniform heat flux

International Nuclear Information System (INIS)

Bhattacharyya Krishnendu

2013-01-01

In this paper, the effect of non-uniform heat flux on heat transfer in boundary layer stagnation-point flow over a shrinking sheet is studied. The variable boundary heat fluxes are considered of two types: direct power-law variation with the distance along the sheet and inverse power-law variation with the distance. The governing partial differential equations (PDEs) are transformed into non linear self-similar ordinary differential equations (ODEs) by similarity transformations, and then those are solved using very efficient shooting method. The direct variation and inverse variation of heat flux along the sheet have completely different effects on the temperature distribution. Moreover, the heat transfer characteristics in the presence of non-uniform heat flux for several values of physical parameters are also found to be interesting

Self-Generated Magnetic Fields in the Stagnation Phase of Indirect-Drive Implosions on the National Ignition Facility

Science.gov (United States)

Walsh, C. A.; Chittenden, J. P.; McGlinchey, K.; Niasse, N. P. L.; Appelbe, B. D.

2017-04-01

Three-dimensional extended-magnetohydrodynamic simulations of the stagnation phase of inertial confinement fusion implosion experiments at the National Ignition Facility are presented, showing self-generated magnetic fields over 104 T . Angular high mode-number perturbations develop large magnetic fields, but are localized to the cold, dense hot-spot surface, which is hard to magnetize. When low-mode perturbations are also present, the magnetic fields are injected into the hot core, reaching significant magnetizations, with peak local thermal conductivity reductions greater than 90%. However, Righi-Leduc heat transport effectively cools the hot spot and lowers the neutron spectra-inferred ion temperatures compared to the unmagnetized case. The Nernst effect qualitatively changes the results by demagnetizing the hot-spot core, while increasing magnetizations at the edge and near regions of large heat loss.

Analytical study of the non orthogonal stagnation point flow of a micro polar fluid

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M. Ali. Abbas

2017-01-01

Full Text Available In this paper we consider the steady two dimensional flow of micro polar fluids on a flat plate. The flow under discussion is the modified Hiemenz flow for a micro polar fluid which occurs in the hjkns + skms boundary layer near an orthogonal stagnation point. The full governing equation reduced to a modified Hiemenz flow. The solution to the boundary value problem is governed by two non dimensional parameters, the material parameter K and the ratio of the micro rotation to skin friction parameter n. The obtained nonlinear coupled ordinary differential equations are solved by using the Homotopy perturbation method. Comparison between numerical and analytical solutions of the problem is shown in tables form for different values of the governing parameters K and n. Effects of the material parameter K on the velocity profile and microrotation profiles for different cases of n are discussed graphically as well as numerically. Velocity profile decreases as the material parameter K increases and the microrotation profile increases as the material parameter K increases for different cases of n.

Achieving performance breakthroughs in an HMO business process through quality planning.

Science.gov (United States)

Hanan, K B

1993-01-01

Kaiser Permanente's Georgia Region commissioned a quality planning team to design a new process to improve payments to its suppliers and vendors. The result of the team's effort was a 73 percent reduction in cycle time. This team's experiences point to the advantages of process redesign as a quality planning model, as well as some general guidelines for its most effective use in teams. If quality planning project teams are carefully configured, sufficiently expert in the existing process, and properly supported by management, organizations can achieve potentially dramatic improvements in process performance using this approach.

The effects of chronic achievement motivation and achievement primes on the activation of achievement and fun goals.

Science.gov (United States)

Hart, William; Albarracín, Dolores

2009-12-01

This research examined the hypothesis that situational achievement cues can elicit achievement or fun goals depending on chronic differences in achievement motivation. In 4 studies, chronic differences in achievement motivation were measured, and achievement-denoting words were used to influence behavior. The effects of these variables were assessed on self-report inventories, task performance, task resumption following an interruption, and the pursuit of means relevant to achieving or having fun. Findings indicated that achievement priming (vs. control priming) activated a goal to achieve and inhibited a goal to have fun in individuals with chronically high-achievement motivation but activated a goal to have fun and inhibited a goal to achieve in individuals with chronically low-achievement motivation.

Achievement Emotions and Academic Performance: Longitudinal Models of Reciprocal Effects.

Science.gov (United States)

Pekrun, Reinhard; Lichtenfeld, Stephanie; Marsh, Herbert W; Murayama, Kou; Goetz, Thomas

2017-09-01

A reciprocal effects model linking emotion and achievement over time is proposed. The model was tested using five annual waves of the Project for the Analysis of Learning and Achievement in Mathematics (PALMA) longitudinal study, which investigated adolescents' development in mathematics (Grades 5-9; N = 3,425 German students; mean starting age = 11.7 years; representative sample). Structural equation modeling showed that positive emotions (enjoyment, pride) positively predicted subsequent achievement (math end-of-the-year grades and test scores), and that achievement positively predicted these emotions, controlling for students' gender, intelligence, and family socioeconomic status. Negative emotions (anger, anxiety, shame, boredom, hopelessness) negatively predicted achievement, and achievement negatively predicted these emotions. The findings were robust across waves, achievement indicators, and school tracks, highlighting the importance of emotions for students' achievement and of achievement for the development of emotions. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Distinguishing the desire to learn from the desire to perform: The social value of achievement goals.

Science.gov (United States)

Cohen, Joanna; Darnon, Céline; Mollaret, Patrick

2017-01-01

We sought to distinguish mastery goals (i.e., desire to learn) from performance goals (i.e., desire to achieve more positive evaluations than others) in the light of social judgment research. In a pilot study, we made a conceptual distinction between three types of traits (agency, competence, and effort) that are often undifferentiated. We then tested the relevance of this distinction for understanding how people pursuing either mastery or performance goals are judged. On self-perception, results revealed that effort was predicted by the adoption of mastery goals and agency by performance goals (Study 1). On judgments, results showed that (a) the target pursuing mastery goals was perceived as oriented toward effort, and (b) the target pursuing performance goals was oriented toward agency (Study 2). Finally, these links were shown again by participants who inferred a target's goals from his traits (Study 3). Results are discussed in terms of the social value of achievement goals at school.

On the achievable performance using variable geometry active secondary suspension systems in commercial vehicles

NARCIS (Netherlands)

Evers, W.J.; Besselink, I.G.M.; Teerhuis, A.P.; Nijmeijer, H.

2011-01-01

There is a need to further improve driver comfort in commercial vehicles. The variable geometry active suspension offers an interesting option to achieve this in an energy efficient way. However, the optimal control strategy and the overal performance potential remains unclear. The aim of this paper

Comparisons of Student Achievement Levels by District Performance and Poverty. ACT Research Report Series 2016-11

Science.gov (United States)

Dougherty, Chrys; Shaw, Teresa

2016-01-01

This report looks at student achievement levels in Arkansas school districts disaggregated by district poverty and by the district's performance relative to other districts. We estimated district performance statistics by subject and grade level (4, 8, and 11-12) for longitudinal student cohorts, using statistical models that adjusted for district…

A meta-analysis of the impact of situationally induced achievement goals on task performance

NARCIS (Netherlands)

Van Yperen, Nico W.; Blaga, Monica; Postmes, Thomas

2015-01-01

The purpose of this research was to meta-analyze studies which experimentally induced an achieve- ment goal state to examine its causal effect on the individual’s performance at the task at hand, and to investigate the moderator effects of feedback anticipation and time pressure. The data set

Predicting race performance in triathlon: the role of perfectionism, achievement goals, and personal goal setting.

Science.gov (United States)

Stoeber, Joachim; Uphill, Mark A; Hotham, Sarah

2009-04-01

The question of how perfectionism affects performance is highly debated. Because empirical studies examining perfectionism and competitive sport performance are missing, the present research investigated how perfectionism affected race performance and what role athletes' goals played in this relationship in two prospective studies with competitive triathletes (Study 1: N = 112; Study 2: N = 321). Regression analyses showed that perfectionistic personal standards, high performance-approach goals, low performance-avoidance goals, and high personal goals predicted race performance beyond athletes' performance level. Moreover, the contrast between performance-avoidance and performance-approach goals mediated the relationship between perfectionistic personal standards and performance, whereas personal goal setting mediated the relationship between performance-approach goals and performance. The findings indicate that perfectionistic personal standards do not undermine competitive performance, but are associated with goals that help athletes achieve their best possible performance.

Key Performance Indicator (KPI) for Research and Technology Development Program: Achievements of 2006 to 2015

International Nuclear Information System (INIS)

Nik Arlina Nik Ali; Fairuz Faisal

2016-01-01

Conducting research and development (R&D) is one of the four main functions of Malaysian Nuclear Agency as stated in the Federal Government Gazette (No.2) 2013 (PU (A) 184) under the Ministerial Functions Act 1969 (Act 2), gazetted in the Warta Kerajaan dated 26 June 2013.The achievement of Key Performance Indicators (KPI) for Research and Technological Development Program (PPT) indicates the role of Nuclear Malaysia as a research institution . This paper discusses the achievements of the project, fundsand research outputfrom 2005 to 2015. (author)

The honeymoon effect in job performance - Temporal increases in the predictive power of achievement motivation

Science.gov (United States)

Helmreich, Robert L.; Sawin, Linda L.; Carsrud, Alan L.

1986-01-01

Correlations between a job performance criterion and personality measures reflecting achievement motivation and an interpersonal orientation were examined at three points in time after completion of job training for a sample of airline reservations agents. Although correlations between the personality predictors and performance were small and nonsignificant for the 3-month period after beginning the job, by the end of six and eight months a number of significant relationships had emerged. Implications for the utility of personality measures in selection and performance prediction are discussed.

Relationships of cognitive and metacognitive learning strategies to mathematics achievement in four high-performing East Asian education systems.

Science.gov (United States)

Areepattamannil, Shaljan; Caleon, Imelda S

2013-01-01

The authors examined the relationships of cognitive (i.e., memorization and elaboration) and metacognitive learning strategies (i.e., control strategies) to mathematics achievement among 15-year-old students in 4 high-performing East Asian education systems: Shanghai-China, Hong Kong-China, Korea, and Singapore. In all 4 East Asian education systems, memorization strategies were negatively associated with mathematics achievement, whereas control strategies were positively associated with mathematics achievement. However, the association between elaboration strategies and mathematics achievement was a mixed bag. In Shanghai-China and Korea, elaboration strategies were not associated with mathematics achievement. In Hong Kong-China and Singapore, on the other hand, elaboration strategies were negatively associated with mathematics achievement. Implications of these findings are briefly discussed.

Implementation of Kaizen in industrial company: a case study

OpenAIRE

Simões, Alexandre Manuel Portugal

2014-01-01

Kaizen has become increasingly used when it comes to improve performance of organizations. Kaizen means continuous improvement. Therefore, the question posed is what improvements are achieved with kaizen application and whether the achieved results will continue throughout time or tend to stagnate soon afterwards. For that purpose a case study was realized on the company “Porcelanas da Costa Verde, S.A.”, assessing what were the changes, the outcomes and the continuity or not of the improveme...

Oxidation of iridium coating on rhenium coated graphite at elevated temperature in stagnated air

International Nuclear Information System (INIS)

Huang, Yongle; Bai, Shuxin; Zhang, Hong; Ye, Yicong

2015-01-01

Highlights: • Continuous and dense Ir coatings were prepared on graphite by electrodepostion. • The purification of the as-prepared Ir coating was higher than about 99.98%. • The Ir/Re/C specimen kept integrity without significant failures after oxidation. • The average oxidation rate of the Ir coating was about 0.219 mg/(cm 2 min). • Penetrating holes at gains boundaries resulted in the failure of the Ir coating. - Abstract: Continuous and dense iridium coatings were prepared on the rhenium coated graphite specimens by electrodeposition. The iridium/rhenium coated graphite (Ir/Re/C) specimens were oxidized at elevated temperatures in stagnated air for 3600 s. The purification of the as-prepared Ir coating was higher than about 99.98% with the main impurity elements Si, Al, Fe and Ru. After oxidation, the Ir/Re/C specimens kept integrity without significant failures and the average oxidation rate was about 0.219 mg/(cm 2 min). Pores were found at the grain boundaries and concentrated to penetrating holes with the growth of Ir grains, which resulted in disastrous failures of the Ir coating

Oxidation of iridium coating on rhenium coated graphite at elevated temperature in stagnated air

Energy Technology Data Exchange (ETDEWEB)

Huang, Yongle; Bai, Shuxin, E-mail: NUDT_MSE_501@163.com; Zhang, Hong; Ye, Yicong

2015-02-15

Highlights: • Continuous and dense Ir coatings were prepared on graphite by electrodepostion. • The purification of the as-prepared Ir coating was higher than about 99.98%. • The Ir/Re/C specimen kept integrity without significant failures after oxidation. • The average oxidation rate of the Ir coating was about 0.219 mg/(cm{sup 2} min). • Penetrating holes at gains boundaries resulted in the failure of the Ir coating. - Abstract: Continuous and dense iridium coatings were prepared on the rhenium coated graphite specimens by electrodeposition. The iridium/rhenium coated graphite (Ir/Re/C) specimens were oxidized at elevated temperatures in stagnated air for 3600 s. The purification of the as-prepared Ir coating was higher than about 99.98% with the main impurity elements Si, Al, Fe and Ru. After oxidation, the Ir/Re/C specimens kept integrity without significant failures and the average oxidation rate was about 0.219 mg/(cm{sup 2} min). Pores were found at the grain boundaries and concentrated to penetrating holes with the growth of Ir grains, which resulted in disastrous failures of the Ir coating.

Achieving excellence in human performance through leadership, education, and training in nuclear power industry

International Nuclear Information System (INIS)

Clark, C.R.; Kazennov, A.; Kossilov, A.; Mazour, T.; Yoder, J.

2004-01-01

Full text: In order to achieve and maintain high levels of safety and productivity, nuclear power plants are required to be staffed with an adequate number of highly qualified and experienced personnel who are duly aware of the technical and administrative requirements for safety and are motivated to adopt a positive attitude to safety, as an element of safety culture. To establish and maintain a high level of human performance, appropriate education and training programmes should be in place and kept under constant review to ensure their relevance. As the nuclear power industry continues to be challenged by increasing safety requirements, a high level of competition and decreasing budgets, it becomes more important than ever to maintain excellence in human performance and ensure that NPP personnel training provides a value to the organization. Nuclear industry managers and supervisors bear the primary responsibility to assure that people perform their jobs safely and effectively. Training personnel must be responsive to the needs of the organization, working hand-in-hand with line managers and supervisors to ensure that human performance improvement needs are properly analyzed, and that training as well as other appropriate interventions are developed and implemented in the most effective and efficient way possible. The International Atomic Energy Agency together with its Member States has provided for coordinated information exchange and developed guidance on methods and practices to identify and improve the effectiveness NPP personnel training. This has resulted in: plant performance improvements, improved human performance, meeting goals and objectives of the business (quality, safety, productivity), and more effective training programs. This article describes the IAEA activities and achievements in the subject area for systematically understanding and improving human performance in nuclear power industry. The article also describes cooperation programmes

Study on changes of hypothalamus-pituitary-target axis hormones in patients with insomnia of fire-symdrome due to the stagnation

International Nuclear Information System (INIS)

Chen Jianfei; Yan Songqin

2007-01-01

Objective: To study the changes of hypothalamus-pituitary-target axis hormones in patients with insomnia of fire-symdrom due to the stagnation of liver-qi. Methods: Serum thyrotropin-releasing hormone (TRH), thyroid stimulating hormone (TSH), growth hormone (GH), free thyroxine (FT 4 ), cortisol levels were measured with immunoradioassay (IMRA) and radioimmunoassay (RIA) in 30 patients with this type of insomnia and 30 controls. Results: The serum TSH levels were significantly lower and serum TRH, GH, cortisol FT 4 levels were significantly higher in the patients than those in controls (P<0.05 or P<0.01). Conclusion: This insomnia syndrome was closely related to the dysfunction of mpothalamus-pituitary-thyroid and adrenal axis. (authors)

A mediation analysis of achievement motives, goals, learning strategies, and academic achievement.

Science.gov (United States)

Diseth, Age; Kobbeltvedt, Therese

2010-12-01

Previous research is inconclusive regarding antecedents and consequences of achievement goals, and there is a need for more research in order to examine the joint effects of different types of motives and learning strategies as predictors of academic achievement. To investigate the relationship between achievement motives, achievement goals, learning strategies (deep, surface, and strategic), and academic achievement in a hierarchical model. Participants were 229 undergraduate students (mean age: 21.2 years) of psychology and economics at the University of Bergen, Norway. Variables were measured by means of items from the Achievement Motives Scale (AMS), the Approaches and Study Skills Inventory for Students, and an achievement goal scale. Correlation analysis showed that academic achievement (examination grade) was positively correlated with performance-approach goal, mastery goal, and strategic learning strategies, and negatively correlated with performance-avoidance goal and surface learning strategy. A path analysis (structural equation model) showed that achievement goals were mediators between achievement motives and learning strategies, and that strategic learning strategies mediated the relationship between achievement goals and academic achievement. This study integrated previous findings from several studies and provided new evidence on the direct and indirect effects of different types of motives and learning strategies as predictors of academic achievement.

Modeling relationships of achievement motivation and physical fitness with academic performance in Japanese schoolchildren: Moderation by gender.

Science.gov (United States)

Ishihara, Toru; Morita, Noriteru; Nakajima, Toshihiro; Okita, Koichi; Sagawa, Masato; Yamatsu, Koji

2018-04-25

The aim of this study was to determine, using structural equation modeling, the comprehensive relationships of achievement motivation (self-fulfillment achievement motivation [SFAM] and competitive achievement motivation [CAM]), daily behaviors (exercise habits, screen time, and learning duration), body mass index [BMI], and cardiorespiratory fitness [CRF]) with academic performance among schoolchildren. Three hundred twenty-five schoolchildren (172 males and 153 females; 12-13 years old) were recruited. Academic performance was assessed using the total grade points in 8 academic subjects (GP8); CRF using the 20-m shuttle run; and achievement motivation, daily behaviors, and socioeconomic status using questionnaires. Socioeconomic status was included as a control variable. In males, two cascade associations of achievement motivation to GP8 were detected: (1) SFAM → screen time/learning duration → GP8, and (2) CAM → exercise habit → CRF → GP8 (χ 2  = 8.72, p = .19, AGFI = .92). In females, two cascade associations were also detected: (1) SFAM → screen time/learning habit → GP8, and (2) exercise habit → BMI 2  → GP8 (χ 2  = 6.17, p = .41, AGFI = .93). Our results suggest that greater achievement motivation is associated with academic success via various physiological/behavioral factors, and that these associations differ by gender. Copyright © 2018. Published by Elsevier Inc.

Numerical study of unsteady MHD oblique stagnation point flow and heat transfer due to an oscillating stream

Science.gov (United States)

Javed, T.; Ghaffari, A.; Ahmad, H.

2016-05-01

The unsteady stagnation point flow impinging obliquely on a flat plate in presence of a uniform applied magnetic field due to an oscillating stream has been studied. The governing partial differential equations are transformed into dimensionless form and the stream function is expressed in terms of Hiemenz and tangential components. The dimensionless partial differential equations are solved numerically by using well-known implicit finite difference scheme named as Keller-box method. The obtained results are compared with those available in the literature. It is observed that the results are in excellent agreement with the previous studies. The effects of pertinent parameters involved in the problem namely magnetic parameter, Prandtl number and impinging angle on flow and heat transfer characteristics are illustrated through graphs. It is observed that the influence of magnetic field strength increases the fluid velocity and by the increase of obliqueness parameter, the skin friction increases.

Life Disparity before, during and after Stagnation of Danish Female Life Expectancy. a Cause of Death Analysis and a Comparison with Their Scandinavian Counterparts

DEFF Research Database (Denmark)

Aburto, José Manuel; Wensink, Maarten Jan; Lindahl-Jacobsen, Rune

that as Norway increasingly came to resemble Sweden in terms of high life expectancy, it also came to resemble Sweden in terms of low lifespan inequality. Next, we aim to make similar decompositions for Sweden and Norway, and aim to disentangle cohort effects from the question: what can Denmark do now...... cancers and non-infectious respiratory diseases, offsetting continuous improvement in cardiovascular mortality. Before and after stagnation, life expectancy increased as disparity decreased, as the cardiovascular revolution unfolded. Comparing Denmark and its Scandinavian counterparts, we find...

Metacognition, achievement goals, study strategies and academic achievement: pathways to achievement

NARCIS (Netherlands)

Vrugt, A.; Oort, F.J.

2008-01-01

The purpose of this research was to develop and test a model of effective selfregulated learning. Based on effort expenditure we discerned effective self-regulators and less effective self-regulators. The model comprised achievement goals (mastery, performance-approach and -avoidance goals),

Influence of de qi on the immediate analgesic effect of SP6 acupuncture in patients with primary dysmenorrhoea and cold and dampness stagnation: a multicentre randomised controlled trial.

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Zhao, Min-Yi; Zhang, Peng; Li, Jing; Wang, Lin-Peng; Zhou, Wei; Wang, Yan-Xia; She, Yan-Fen; Ma, Liang-Xiao; Wang, Pei; Hu, Ni-Juan; Lin, Chi; Hu, Shang-Qin; Wu, Gui-Wen; Wang, Ya-Feng; Sun, Jun-Jun; Jiang, Si-Zhu; Zhu, Jiang

2017-10-01

The aim of this multicentre randomised controlled trial was to investigate the contribution of de qi to the immediate analgesic effect of acupuncture in patients with primary dysmenorrhoea and the specific traditional Chinese medicine diagnosis cold and dampness stagnation . Eighty-eight patients with primary dysmenorrhoea and cold and dampness stagnation were randomly assigned to de qi (n=43) or no de qi (n=45) groups and underwent 30 min of SP6 acupuncture. The de qi group received deep needling at SP6 with manipulation using thick needles; the no de qi group received shallow needling with no manipulation using thin needles. In both groups the pain scores and actual de qi sensation were evaluated using a visual analogue scale for pain (VAS-P) and the acupuncture de qi clinical assessment scale (ADCAS), respectively. Both groups showed reductions in VAS-P, with no signficant differences between groups. ADCAS scores showed 43/43 and 25/45 patients in de qi and no de qi groups, respectively, actually experienced de qi sensation. Independent of original group allocation, VAS-P reductions associated with actual de qi (n=68) were greater than those without (28.4±18.19 mm vs 14.6±12.28 mm, p=0.008). This study showed no significant difference in VAS-P scores in patients with primary dysmenorrhoea and cold and dampness stagnation immediately after SP6 acupuncture designed to induce or avoid de qi sensation. Both treatments significantly reduced VAS-P relative to baseline. Irrespective of group allocation, patients experiencing actual de qi sensation demonstrated larger reductions in pain score relative to those without, suggesting greater analgesic effects. Chinese Clinical Trial Registry (ChiCTR-TRC-13003086); Results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

The stagnation of the Mexican male life expectancy in the first decade of the 21st century: the impact of homicides and diabetes mellitus.

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Canudas-Romo, Vladimir; García-Guerrero, Víctor Manuel; Echarri-Cánovas, Carlos Javier

2015-01-01

In the first decade of the 21st century, the Mexican life expectancy changed from a long trend of increase to stagnation. These changes concur with an increase in deaths by homicides that the country experienced in that decade, and an obesity epidemic that had developed over the last decades of the 20th century. We quantify the impact of causes of death on life expectancy from 2000 to 2010. Two approaches to analyse causes of death are used: the number of life years lost due to each of the causes of death in a given year, and cause-decomposition techniques for comparisons of life expectancy from 2000 to 2010. The apparent stagnation in life expectancy is the result of an increase in deaths by homicides and diabetes mellitus on the one hand, and the positive improvements observed in other causes of death on the other. The negative impact of homicides is particularly observed for ages 15 and 50, and for that of diabetes mellitus at ages above 45 years. There is little basis for optimism regarding the future scenarios of the health of the Mexican population based on the first decade of the 21st century. Male life expectancy would have increased by 2 years if deaths by homicides and diabetes mellitus had been avoided. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

A Comprehensive Review of the Literature on the Effects of Breakfast on Mental Performance and Scholastic Achievement.

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Purnell, James P.

A review of the literature on the effects of breakfast on mental performance and scholastic achievement reveals a dichotomy between the theoretical and the empirical literature. Whereas theoretical considerations maintain that breakfast makes a significant difference in mental performance in the late morning hours, empirical evidence can be…

The Influence of the Antecedent Variable on the Teachers' Performance through Achievement Motivation in Senior High School

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Dewi, Erni R.; Bundu, Patta; Tahmir, Suradi

2016-01-01

This study aims at analysing whether the antecedent variable directly affects the performance of the high school teachers or not. In addition, this research strives to find out whether the antecedent variable indirectly affects the teachers' performance through the achievement motivation of the high school teachers. It was a quantitative research…

Stagnation point flow on bioconvection nanofluid over a stretching/shrinking surface with velocity and thermal slip effects

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Chan, Sze Qi; Aman, Fazlina; Mansur, Syahira

2017-09-01

Nanofluid containing nanometer sized particles has become an ideal thermal conductivity medium for the flow and heat transfer in many industrial and engineering applications due to their high rate of heat transfer. However, swimming microorganisms are imposed into the nanofluid to overcome the instability of nanoparticles due to a bioconvection phenomenon. This paper investigates the stagnation point flow on bioconvection heat transfer of a nanofluid over a stretching/shrinking surface containing gyrotactic microorganisms. Velocity and thermal slip effects are the two conditions incorporated into the model. Similarity transformation is applied to reduce the governing nonlinear partial differential equations into the nonlinear ordinary differential equations. The transformed equations are then solved numerically. The results are displayed in the form of graphs and tables. The effects of these governing parameters on the skin friction coefficient, local Nusselt number, local Sherwood number and the local density of the motile microorganisms are analysed and discussed in details.

Analysis Of Convective Plane Stagnation Point Chemically Reactive Mhd Flow Past A Vertical Porous Plate With A Convective Boundary Condition In The Presence Of A Uniform Magnetic Field.

OpenAIRE

Adeniyan, A.,

2013-01-01

The numerical investigation of a stagnation point boundary layer flow , mass and heat transfer of a steady two dimensional , incompressible , viscous electrically conducting, chemically reacting laminar fluid over a vertical convectively heated , electrically neutral flat plate exposed to a transverse uniform magnetic field has been carried out to examine the influence of the simultaneous presence of the effects of a convective boundary condition, chemical reaction, heat transfer and suctio...

Large eddy simulation of premixed and non-premixed combustion in a Stagnation Point Reverse Flow combustor

Science.gov (United States)

Undapalli, Satish

A new combustor referred to as Stagnation Point Reverse Flow (SPRF) combustor has been developed at Georgia Tech to meet the increasingly stringent emission regulations. The combustor incorporates a novel design to meet the conflicting requirements of low pollution and high stability in both premixed and non-premixed modes. The objective of this thesis work is to perform Large Eddy Simulations (LES) on this lab-scale combustor and elucidate the underlying physics that has resulted in its excellent performance. To achieve this, numerical simulations have been performed in both the premixed and non-premixed combustion modes, and velocity field, species field, entrainment characteristics, flame structure, emissions, and mixing characteristics have been analyzed. Simulations have been carried out first for a non-reactive case to resolve relevant fluid mechanics without heat release by the computational grid. The computed mean and RMS quantities in the non-reacting case compared well with the experimental data. Next, the simulations were extended for the premixed reactive case by employing different sub-grid scale combustion chemistry closures: Eddy Break Up (EBU), Artificially Thickened Flame (TF) and Linear Eddy Mixing (LEM) models. Results from the EBU and TF models exhibit reasonable agreement with the experimental velocity field. However, the computed thermal and species fields have noticeable discrepancies. Only LEM with LES (LEMLES), which is an advanced scalar approach, has been able to accurately predict both the velocity and species fields. Scalar mixing plays an important role in combustion, and this is solved directly at the sub-grid scales in LEM. As a result, LEM accurately predicts the scalar fields. Due to the two way coupling between the super-grid and sub-grid quantities, the velocity predictions also compare very well with the experiments. In other approaches, the sub-grid effects have been either modeled using conventional approaches (EBU) or need

Achievement goals affect metacognitive judgments

Science.gov (United States)

Ikeda, Kenji; Yue, Carole L.; Murayama, Kou; Castel, Alan D.

2017-01-01

The present study examined the effect of achievement goals on metacognitive judgments, such as judgments of learning (JOLs) and metacomprehension judgments, and actual recall performance. We conducted five experiments manipulating the instruction of achievement goals. In each experiment, participants were instructed to adopt mastery-approach goals (i.e., develop their own mental ability through a memory task) or performance-approach goals (i.e., demonstrate their strong memory ability through getting a high score on a memory task). The results of Experiments 1 and 2 showed that JOLs of word pairs in the performance-approach goal condition tended to be higher than those in the mastery-approach goal condition. In contrast, cued recall performance did not differ between the two goal conditions. Experiment 3 also demonstrated that metacomprehension judgments of text passages were higher in the performance-approach goal condition than in the mastery-approach goals condition, whereas test performance did not differ between conditions. These findings suggest that achievement motivation affects metacognitive judgments during learning, even when achievement motivation does not influence actual performance. PMID:28983496

How many trials are needed to achieve performance stability of the Timed Up & Go test in patients with hip fracture?

DEFF Research Database (Denmark)

Kristensen, Morten T; Ekdahl, Charlotte; Kehlet, Henrik

2010-01-01

To examine the number of trials needed to achieve performance stability of the Timed Up & Go (TUG) test using a standardized walking aid in patients with hip fracture who are allowed full weight bearing (FWB).......To examine the number of trials needed to achieve performance stability of the Timed Up & Go (TUG) test using a standardized walking aid in patients with hip fracture who are allowed full weight bearing (FWB)....

Relationship between Motivation to Achieve and Professional Competence in the Performance of Elementary School Teachers

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Sumantri, Mohamad Syarif; Whardani, Prayuningtyas Angger

2017-01-01

This study aims to determine the relationship between achievement motivation and professional competence with regard to the performance of teachers in public elementary schools in Central Java. The quantitative method is used in this study. The results of this study indicate that (1) there is a significant positive relationship between achievement…

Perceived ability and social support as mediators of achievement motivation and performance anxiety.

Science.gov (United States)

Abrahamsen, F E; Roberts, G C; Pensgaard, A M; Ronglan, L T

2008-12-01

The present study is founded on achievement goal theory (AGT) and examines the relationship between motivation, social support and performance anxiety with team handball players (n=143) from 10 elite teams. Based on these theories and previous findings, the study has three purposes. First, it was predicted that the female athletes (n=69) would report more performance worries and more social support use than males (n=74). The findings support the hypothesis for anxiety, but not for social support use. However, females report that they felt social support was more available than males. Second, we predicted and found a positive relationship between the interaction of ego orientation and perceptions of a performance climate on performance anxiety, but only for females. As predicted, perceived ability mediated this relationship. Finally, we predicted that perceptions of a performance climate were related to the view that social support was less available especially for the male athletes. Simple correlation supports this prediction, but the regression analyses did not reach significance. Thus, we could not test for mediation of social support between motivational variables and anxiety. The results illustrate that fostering a mastery climate helps elite athletes tackle competitive pressure.

Four Language Skills Performance, Academic Achievement, and Learning Strategy Use in Preservice Teacher Training Programs

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Shawer, Saad Fathy

2016-01-01

This article examines the differences in language learning strategies (LLS) use between preservice teachers of English as a foreign language (EFL) and Arabic as a second language (ASL). It also examines the relationship between LLS use and language performance (academic achievement and four language skills) among ASL students. The study made use…

Pilot study: EatFit impacts sixth graders' academic performance on achievement of mathematics and english education standards.

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Shilts, Mical Kay; Lamp, Cathi; Horowitz, Marcel; Townsend, Marilyn S

2009-01-01

Investigate the impact of a nutrition education program on student academic performance as measured by achievement of education standards. Quasi-experimental crossover-controlled study. California Central Valley suburban elementary school (58% qualified for free or reduced-priced lunch). All sixth-grade students (n = 84) in the elementary school clustered in 3 classrooms. 9-lesson intervention with an emphasis on guided goal setting and driven by the Social Cognitive Theory. Multiple-choice survey assessing 5 education standards for sixth-grade mathematics and English at 3 time points: baseline (T1), 5 weeks (T2), and 10 weeks (T3). Repeated measures, paired t test, and analysis of covariance. Changes in total scores were statistically different (P academic performance measured by achievement of specific mathematics and English education standards. Nutrition educators can show school administrators and wellness committee members that this program can positively impact academic performance, concomitant to its primary objective of promoting healthful eating and physical activity.

Study strategies and beliefs about learning as a function of academic achievement and achievement goals.

Science.gov (United States)

Geller, Jason; Toftness, Alexander R; Armstrong, Patrick I; Carpenter, Shana K; Manz, Carly L; Coffman, Clark R; Lamm, Monica H

2018-05-01

Prior research by Hartwig and Dunlosky [(2012). Study strategies of college students: Are self-testing and scheduling related to achievement? Psychonomic Bulletin & Review, 19(1), 126-134] has demonstrated that beliefs about learning and study strategies endorsed by students are related to academic achievement: higher performing students tend to choose more effective study strategies and are more aware of the benefits of self-testing. We examined whether students' achievement goals, independent of academic achievement, predicted beliefs about learning and endorsement of study strategies. We administered Hartwig and Dunlosky's survey, along with the Achievement Goals Questionnaire [Elliot, A. J., & McGregor, H. A. (2001). A 2 × 2 achievement goal framework. Journal of Personality & Social Psychology, 80, 501-519] to a large undergraduate biology course. Similar to results by Hartwig and Dunlosky, we found that high-performing students (relative to low-performing students) were more likely to endorse self-testing, less likely to cram, and more likely to plan a study schedule ahead of time. Independent of achievement, however, achievement goals were stronger predictors of certain study behaviours. In particular, avoidance goals (e.g., fear of failure) coincided with increased use of cramming and the tendency to be driven by impending deadlines. Results suggest that individual differences in student achievement, as well as the underlying reasons for achievement, are important predictors of students' approaches to studying.

Achieving palliative care research efficiency through defining and benchmarking performance metrics.

Science.gov (United States)

Lodato, Jordan E; Aziz, Noreen; Bennett, Rachael E; Abernethy, Amy P; Kutner, Jean S

2012-12-01

Research efficiency is gaining increasing attention in the research enterprise, including palliative care research. The importance of generating meaningful findings and translating these scientific advances to improved patient care creates urgency in the field to address well documented system inefficiencies. The Palliative Care Research Cooperative Group (PCRC) provides useful examples for ensuring research efficiency in palliative care. Literature on maximizing research efficiency focuses on the importance of clearly delineated process maps, working instructions, and standard operating procedures in creating synchronicity in expectations across research sites. Examples from the PCRC support these objectives and suggest that early creation and employment of performance metrics aligned with these processes are essential to generate clear expectations and identify benchmarks. These benchmarks are critical in effective monitoring and ultimately the generation of high-quality findings that are translatable to clinical populations. Prioritization of measurable goals and tasks to ensure that activities align with programmatic aims is critical. Examples from the PCRC affirm and expand the existing literature on research efficiency, providing a palliative care focus. Operating procedures, performance metrics, prioritization, and monitoring for success should all be informed by and inform the process map to achieve maximum research efficiency.

Performance measures for improving the prevention of venous thromboembolism: achievement in clinical practice.

Science.gov (United States)

Wilson, Kenneth C; Merli, Geno J

2011-10-01

Venous thromboembolism (VTE) is a common complication during and after hospitalization for acute medical illness or surgery. Despite the existence of evidence-based guidelines for VTE prevention, real-world prescribing practices are frequently suboptimal. Specific performance measures relating to VTE prevention and treatment have been developed by US health care organizations to increase adherence with best-practice recommendations and ultimately reduce the number of preventable VTE events. Two measures developed by the Surgical Care Improvement Project have been endorsed by the National Quality Forum (NQF) and focus on VTE prevention. In addition, six measures have been developed recently by The Joint Commission in collaboration with the NQF; three measures relate to VTE prevention and three focus on treatment. To attain widespread achievement of these performance goals, it is essential to raise awareness of their existence and specifications. It is also imperative that hospitals develop and implement effective VTE protocols. The use of multiple, active strategies, such as computer decision support systems with regular audit and feedback, may be particularly valuable approaches to improve current practices within an integrated quality improvement program. During practical implementation of VTE protocols at Norton Healthcare (Kentucky's largest healthcare system), strong leadership, physician engagement, and caregiver accountability were identified as key factors influencing the process. As such, more hospitals may be able to increase adherence with guidelines, improve achievement of quality goals, and help to reduce the substantial burden associated with avoidable VTE.

INFORMATION SYSTEM DESIGN OF PERFORMANCE ACHIEVEMENTS MONITORING IN THE UNIVERSITY: A CASE STUDY IN BINUS UNIVERSITY

Directory of Open Access Journals (Sweden)

Irma Irawati Ibrahim

2012-05-01

Full Text Available Dashboard is a computer interface that displays a variety of charts, graphs, tables, which are selected reports from various data that are considered important to display rapidly, with an attractive appearance, dynamic, and relevant so that it can immediately be seen quickly to analyze a condition. Dashboard information system is widely used in various companies as a support system for decision-making where Dashboard usually displays data business trends of the company or the achievement of KPI (Key Performance Indicator of a company. The method used is descriptive analysis by means of collecting information that areimportant for universities to be considered asthe Key Success Factors (KSF of the university, and then, the design of the dashboard is made in accordance with these important factors.The result of this study is a grand design of information systems for the university performance monitoring, starting from the reception of students, faculty performance, student academic achievement, effectiveness and efficiency of services, including graduates. It is expected that by the time the system has been fully implemented, the university can take action quickly and accurately with respect to the required conditions.Keywords: Information System Dashboard; Dashboard; Academic Dashboard; University Dashboard

Configurational Paths to Social Performance in SMEs: The Interplay of Innovation, Sustainability, Resources and Achievement Motivation

Directory of Open Access Journals (Sweden)

Sascha Kraus

2017-10-01

Full Text Available In today’s world of increasing ecological, social and economic issues, the question as to how businesses can become a vehicle towards more sustainable development has become more relevant than ever. Crucial to a more sustainable economy is the successful implementation of sustainable practices through entrepreneurial activities. Although there are attempts to describe how sustainable entrepreneurs differentiate themselves, the question of how some entrepreneurs manage to successfully create a sustainable enterprise, while others do not, remains unanswered. The aim of this research is to find causal patterns that explain the success of sustainable entrepreneurs, using their social performance as a measure. Using a configuration approach-based fuzzy set qualitative comparative analysis (fsQCA of 598 Austrian small- and medium-sized enterprises (SMEs, we could identify four different combinations of the interconnected variables of innovation orientation, environmental sustainability, resource leveraging and achievement motivation, which all lead to social performance depending on the respective networking intensity of the firms. The only variable that is included in all combinations is environmental sustainability, thus indicating it may be either crucial to or a prerequisite for achieving social performance in SMEs.

High school achievement as a predictor for university performance

Directory of Open Access Journals (Sweden)

Meshkani Z

2004-07-01

Full Text Available Background: The high-school grade point average ( GPA-H and university entrance examination can predict the university achievement and Purpose. To examine the predictive value of GPA-H for GPA-U Methods: In this cross sectional study, the subjects were 240 medical students at basic science phase of their medical education. Data were collected by a questionnaire, consisting of questions measuring factual background variable and 10 Llikert-type questions measuring attitude. The multiple regression analysis was used. Results: The analysis showed that student GPA were a better predictor for educational achievement of medical students than rank on university entrance exam and students with high GPA have not been on probation at all. Also parent's education and occupation influence the students' attitudes toward their medical study. Conclusion: High-school GPA is a predictor for university GPA .This may warrant further investigation into criteria of medical university entrance exam. Keywords: UNIVERSITY ACHIEVEMENT, HIGH-SCHOOL GPA, UNIVERSITY SUCCESS, PREDICTOR

Enriching the hierarchical model of achievement motivation: autonomous and controlling reasons underlying achievement goals.

Science.gov (United States)

Michou, Aikaterini; Vansteenkiste, Maarten; Mouratidis, Athanasios; Lens, Willy

2014-12-01

The hierarchical model of achievement motivation presumes that achievement goals channel the achievement motives of need for achievement and fear of failure towards motivational outcomes. Yet, less is known whether autonomous and controlling reasons underlying the pursuit of achievement goals can serve as additional pathways between achievement motives and outcomes. We tested whether mastery approach, performance approach, and performance avoidance goals and their underlying autonomous and controlling reasons would jointly explain the relation between achievement motives (i.e., fear of failure and need for achievement) and learning strategies (Study 1). Additionally, we examined whether the autonomous and controlling reasons underlying learners' dominant achievement goal would account for the link between achievement motives and the educational outcomes of learning strategies and cheating (Study 2). Six hundred and six Greek adolescent students (Mage = 15.05, SD = 1.43) and 435 university students (Mage M = 20.51, SD = 2.80) participated in studies 1 and 2, respectively. In both studies, a correlational design was used and the hypotheses were tested via path modelling. Autonomous and controlling reasons underlying the pursuit of achievement goals mediated, respectively, the relation of need for achievement and fear of failure to aspects of learning outcomes. Autonomous and controlling reasons underlying achievement goals could further explain learners' functioning in achievement settings. © 2014 The British Psychological Society.

When nursing takes ownership of financial outcomes: achieving exceptional financial performance through leadership, strategy, and execution.

Science.gov (United States)

Goetz, Kristopher; Janney, Michelle; Ramsey, Kristin

2011-01-01

With nurses and unlicensed supportive personnel composing the greatest percentage of the workforce at any hospital, it is not surprising nursing leadership plays an increasing role in the attainment of financial goals. The nursing leadership team at one academic medical center reduced costs by more than $10 million over 4 years while outperforming national benchmarks on nurse-sensitive quality indicators. The most critical success factor in attaining exceptional financial performance is a personal and collective accountability to achieving outcomes. Whether it is financial improvement, advancing patient safety, or ensuring a highly engaged workforce, success will not be attained without thoughtful, focused leadership. The accountability model ensures there is a culture built around financial performance where nurses and leaders think and act, on a daily basis, in a manner necessary to understand opportunities, find answers, and overcome obstacles. While structures, processes, and tools may serve as the means to achieve a target, it is leadership's responsibility to set the right goal and motivate others.

Achievement goals and perfectionism of high school students

Directory of Open Access Journals (Sweden)

Milojević Milica

2009-01-01

Full Text Available This research has been investigating one of the most contemporary approaches of achievement motivation - Achievement Goal Theory, which uses the construct of achievement goals. The construct of achievement goals involves three types of achievement goals: mastery goals, performance approach goals and performance avoidance goals. The main goal of the research was to examine correlation between perfectionism and its aspects with particular types of achievement goals. Also, the goal was to investigate the difference concerning gender regarding the achievement goals. The sample consisted of 200 senior year high school participants. The following instruments were used: Multi-dimensional scale of perfectionism (MSP and Test of achievement goals (TCP. The research results indicate that there is significant positive correlation between: perfectionism with performance approach goals and performance avoidance goals, concern over mistakes and parental expectations with performance approach goals and performance avoidance goals, personal standards and organization with mastery goals and performance approach goals, parental criticism and doubts about action with performance avoidance goals. Significant negative correlation was found between parental criticism and mastery goals. The results concerning the second goal indicates the female subjects have higher average scores in mastery goals.

Impacts of variable thermal conductivity on stagnation point boundary layer flow past a Riga plate with variable thickness using generalized Fourier's law

Science.gov (United States)

Shah, S.; Hussain, S.; Sagheer, M.

2018-06-01

This article explores the problem of two-dimensional, laminar, steady and boundary layer stagnation point slip flow over a Riga plate. The incompressible upper-convected Maxwell fluid has been considered as a rheological fluid model. The heat transfer characteristics are investigated with generalized Fourier's law. The fluid thermal conductivity is assumed to be temperature dependent in this study. A system of partial differential equations governing the flow of an upper-convected Maxwell fluid, heat and mass transfer using generalized Fourier's law is developed. The main objective of the article is to inspect the impacts of pertinent physical parameters such as the stretching ratio parameter (0 ⩽ A ⩽ 0.3) , Deborah number (0 ⩽ β ⩽ 0.6) , thermal relaxation parameter (0 ⩽ γ ⩽ 0.5) , wall thickness parameter (0.1 ⩽ α ⩽ 3.5) , slip parameter (0 ⩽ R ⩽ 1.5) , thermal conductivity parameter (0.1 ⩽ δ ⩽ 1.0) and modified Hartmann number (0 ⩽ Q ⩽ 3) on the velocity and temperature profiles. Suitable local similarity transformations have been used to get a system of non-linear ODEs from the governing PDEs. The numerical solutions for the dimensionless velocity and temperature distributions have been achieved by employing an effective numerical method called the shooting method. It is seen that the velocity profile shows the reduction in the velocity for the higher values of viscoelastic parameter and the thermal relaxation parameter. In addition, to enhance the reliability at the maximum level of the obtained numerical results by shooting method, a MATLAB built-in solver bvp4c has also been utilized.

Behavioral Performance and Neural Areas Associated with Memory Processes Contribute to Math and Reading Achievement in 6-year-old Children.

Science.gov (United States)

Blankenship, Tashauna L; Keith, Kayla; Calkins, Susan D; Bell, Martha Ann

2018-01-01

Associations between working memory and academic achievement (math and reading) are well documented. Surprisingly, little is known of the contributions of episodic memory, segmented into temporal memory (recollection proxy) and item recognition (familiarity proxy), to academic achievement. This is the first study to observe these associations in typically developing 6-year old children. Overlap in neural correlates exists between working memory, episodic memory, and math and reading achievement. We attempted to tease apart the neural contributions of working memory, temporal memory, and item recognition to math and reading achievement. Results suggest that working memory and temporal memory, but not item recognition, are important contributors to both math and reading achievement, and that EEG power during a working memory task contributes to performance on tests of academic achievement.

Achievement Emotions and Academic Performance: Longitudinal Models of Reciprocal Effects

Science.gov (United States)

Pekrun, Reinhard; Lichtenfeld, Stephanie; Marsh, Herbert W.; Murayama, Kou; Goetz, Thomas

2017-01-01

A reciprocal effects model linking emotion and achievement over time is proposed. The model was tested using five annual waves of the Project for the Analysis of Learning and Achievement in Mathematics (PALMA) longitudinal study, which investigated adolescents' development in mathematics (Grades 5-9; N = 3,425 German students; mean starting…

High-Performance and Omnidirectional Thin-Film Amorphous Silicon Solar Cell Modules Achieved by 3D Geometry Design.

Science.gov (United States)

Yu, Dongliang; Yin, Min; Lu, Linfeng; Zhang, Hanzhong; Chen, Xiaoyuan; Zhu, Xufei; Che, Jianfei; Li, Dongdong

2015-11-01

High-performance thin-film hydrogenated amorphous silicon solar cells are achieved by combining macroscale 3D tubular substrates and nanoscaled 3D cone-like antireflective films. The tubular geometry delivers a series of advantages for large-scale deployment of photovoltaics, such as omnidirectional performance, easier encapsulation, decreased wind resistance, and easy integration with a second device inside the glass tube. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

What factors determine academic achievement in high achieving undergraduate medical students? A qualitative study.

Science.gov (United States)

Abdulghani, Hamza M; Al-Drees, Abdulmajeed A; Khalil, Mahmood S; Ahmad, Farah; Ponnamperuma, Gominda G; Amin, Zubair

2014-04-01

Medical students' academic achievement is affected by many factors such as motivational beliefs and emotions. Although students with high intellectual capacity are selected to study medicine, their academic performance varies widely. The aim of this study is to explore the high achieving students' perceptions of factors contributing to academic achievement. Focus group discussions (FGD) were carried out with 10 male and 9 female high achieving (scores more than 85% in all tests) students, from the second, third, fourth and fifth academic years. During the FGDs, the students were encouraged to reflect on their learning strategies and activities. The discussion was audio-recorded, transcribed and analysed qualitatively. Factors influencing high academic achievement include: attendance to lectures, early revision, prioritization of learning needs, deep learning, learning in small groups, mind mapping, learning in skills lab, learning with patients, learning from mistakes, time management, and family support. Internal motivation and expected examination results are important drivers of high academic performance. Management of non-academic issues like sleep deprivation, homesickness, language barriers, and stress is also important for academic success. Addressing these factors, which might be unique for a given student community, in a systematic manner would be helpful to improve students' performance.

An Examination of Secondary School Students' Academic Achievement in Science Course and Achievement Scores in Performance Assignments with Regard to Different Variables: A Boarding School Example

Science.gov (United States)

Bozdogan, Aykut Emre; Günaydin, Esra; Okur, Alperen

2014-01-01

The aim of the study is to explore the academic achievement and performance tasks of students studying in a regional primary boarding school in science course with regard to different variables. The study was carried out via survey method and total 96 students, 57 of them boarding students and 39 of them non-boarding students studying in the 5th,…

Effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation

Science.gov (United States)

M. Salem, A.; Rania, Fathy

2012-05-01

The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic (MHD) heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching sheet embedded in a porous medium are presented, taking into account thermal radiation and internal heat genberation/absorbtion. The stretching velocity and the ambient fluid velocity are assumed to vary linearly with the distance from the stagnation point. The Rosseland approximation is used to describe the radiative heat flux in the energy equation. The governing fundamental equations are first transformed into a system of ordinary differential equations using a scaling group of transformations and are solved numerically by using the fourth-order Rung—Kutta method with the shooting technique. A comparison with previously published work has been carried out and the results are found to be in good agreement. The results are analyzed for the effect of different physical parameters, such as the variable viscosity and thermal conductivity, the ratio of free stream velocity to stretching velocity, the magnetic field, the porosity, the radiation and suction/injection on the flow, and the heat and mass transfer characteristics. The results indicate that the inclusion of variable viscosity and thermal conductivity into the fluids of light and medium molecular weight is able to change the boundary-layer behavior for all values of the velocity ratio parameter λ except for λ = 1. In addition, the imposition of fluid suction increases both the rate of heat and mass transfer, whereas fluid injection shows the opposite effect.

Effects of variable properties on MHD heat and mass transfer flow near a stagnation point towards a stretching sheet in a porous medium with thermal radiation

International Nuclear Information System (INIS)

Salem, A. M.; Fathy, Rania

2012-01-01

The effect of variable viscosity and thermal conductivity on steady magnetohydrodynamic (MHD) heat and mass transfer flow of viscous and incompressible fluid near a stagnation point towards a permeable stretching sheet embedded in a porous medium are presented, taking into account thermal radiation and internal heat genberation/absorbtion. The stretching velocity and the ambient fluid velocity are assumed to vary linearly with the distance from the stagnation point. The Rosseland approximation is used to describe the radiative heat flux in the energy equation. The governing fundamental equations are first transformed into a system of ordinary differential equations using a scaling group of transformations and are solved numerically by using the fourth-order Rung—Kutta method with the shooting technique. A comparison with previously published work has been carried out and the results are found to be in good agreement. The results are analyzed for the effect of different physical parameters, such as the variable viscosity and thermal conductivity, the ratio of free stream velocity to stretching velocity, the magnetic field, the porosity, the radiation and suction/injection on the flow, and the heat and mass transfer characteristics. The results indicate that the inclusion of variable viscosity and thermal conductivity into the fluids of light and medium molecular weight is able to change the boundary-layer behavior for all values of the velocity ratio parameter λ except for λ = 1. In addition, the imposition of fluid suction increases both the rate of heat and mass transfer, whereas fluid injection shows the opposite effect. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

A University Engagement Model for Achieving Technology Adoption and Performance Improvement Impacts in Healthcare, Manufacturing, and Government

Science.gov (United States)

McKinnis, David R.; Sloan, Mary Anne; Snow, L. David; Garimella, Suresh V.

2014-01-01

The Purdue Technical Assistance Program (TAP) offers a model of university engagement and service that is achieving technology adoption and performance improvement impacts in healthcare, manufacturing, government, and other sectors. The TAP model focuses on understanding and meeting the changing and challenging needs of those served, always…

Assessment of the impact that the capsule fill tube has on implosions conducted with high density carbon ablators

Science.gov (United States)

Pak, Arthur; Benedetti, L. R.; Berzak Hopkins, L. F.; Clark, D.; Divol, L.; Dewald, E. L.; Fittinghoff, D.; Izumi, N.; Khan, S. F.; Landen, O.; Lepape, S.; Ma, T.; Marley, E.; Nagel, S.; Volegov, P.; Weber, C.; Bradley, D. K.; Callahan, D.; Grim, G.; Hurricane, O. A.; Patel, P.; Schneider, M. B.; Edwards, M. J.

2017-10-01

In recent inertial confinement implosion experiments conducted at the National Ignition Facility, bright and spatially localized x-ray emission within the hot spot at stagnation has been observed. This emission is associated with higher Z ablator material that is injected into the hot spot by the hydrodynamic perturbation induced by the 5-10 um diameter capsule fill tube. The reactivity of the DT fuel and subsequent yield of the implosion are strongly dependent on the density, temperature, and confinement time achieved throughout the stagnation of the implosion. Radiative losses from higher Z ablator material that mixes into the hot spot as well as non-uniformities in the compression and confinement induced by the fill tube perturbation can degrade the yield of the implosion. This work will examine the impact to conditions at stagnation that results from the fill tube perturbation. This assessment will be based from a pair of experiments conducted with a high density carbon ablator where the only deliberate change was reduction in fill tube diameter from 10 to 5 um. An estimate of the radiative losses and impact on performance from ablator mix injected into the hot spot by the fill tube perturbation will be presented. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Structure and temperature distribution of a stagnation-point Diesel spray premixed flame

International Nuclear Information System (INIS)

Lin, J.-C.; Lin, Ta-Hui

2005-01-01

We experimentally examine the flow and flame characteristics of a stagnation point premixed flame influenced by Diesel sprays. In the experiment, distributions of drop size, drop axial velocity and its fluctuation as well as the gas phase temperature are measured by using the phase-doppler particle analyzer and a thin thermocouple. As might be expected, similar to the gasoline spray flame, the partially prevaporized Diesel spray flame is composed of a weak blue flame zone, indicating the burning of methane fuel, and a strongly luminous zone containing many bright yellow lines showing the passages of burning Diesel drops. It is found that the axial temperature profiles at various radial positions consist of an upstream preheat region, a maximum temperature downstream of the blue flame and a downstream region with a declined temperature curve because of the heat loss to the quartz plate. The SMD of the drops increases from the upstream preheat region to a maximum near the blue flame and then decreases in the downstream burning zone. Along the axial position, the drops are decelerated in front of the flame but accelerated when passing through the blue flame. It is also interesting to note that the radial distributions of SMD and number density of drops in the upstream region are mainly influenced by small drops flowing outward, since the upstream vaporization of Diesel drops is very limited; while those in the downstream region should be influenced by both small drops flowing outward and Diesel drops burning. From the experimental observations, there are impinging and bouncing of Diesel drops downstream of the spray flame near the quartz plate, resulting in a small amount of soot and carbon deposits on the wall. These interesting phenomena will be reported in the near future

Tracking the Market Performance of Companies That Integrate a Culture of Health and Safety: An Assessment of Corporate Health Achievement Award Applicants.

Science.gov (United States)

Fabius, Raymond; Loeppke, Ronald R; Hohn, Todd; Fabius, Dan; Eisenberg, Barry; Konicki, Doris L; Larson, Paul

2016-01-01

The aim of this study was to assess the hypothesis that stock market performance of companies achieving high scores on either health or safety in the Corporate Health Achievement Award (CHAA) process will be superior to average index performance. The stock market performance of portfolios of CHAA winners was examined under six different scenarios using simulation and past market performance in tests of association framed to inform the investor community. CHAA portfolios out-performed the S&P average on all tests. This study adds to the growing evidence that a healthy and safe workforce correlates with a company's performance and its ability to provide positive returns to shareholders. It advances the idea that a proven set of health and safety metrics based on the CHAA evaluation process merits inclusion with existing measures for market valuation.

Gender Differences in Achievement Goals and Performances in English Language and Mathematics of Senior Secondary Schools Students in Borno State, Nigeria

Science.gov (United States)

Musa, Alice K. J.; Dauda, Bala; Umar, Mohammad A.

2016-01-01

The paper investigated gender difference in achievement goals and performance in English Language and Mathematics of senior secondary schools students in Borno State, Nigeria. The study specifically sought to determine gender differences in students' academic performances in English Language, Mathematics and overall academic performance as well as…

Strategies to optimize lithium-ion supercapacitors achieving high-performance: Cathode configurations, lithium loadings on anode, and types of separator

Science.gov (United States)

Cao, Wanjun; Li, Yangxing; Fitch, Brian; Shih, Jonathan; Doung, Tien; Zheng, Jim

2014-12-01

The Li-ion capacitor (LIC) is composed of a lithium-doped carbon anode and an activated carbon cathode, which is a half Li-ion battery (LIB) and a half electrochemical double-layer capacitor (EDLC). LICs can achieve much more energy density than EDLC without sacrificing the high power performance advantage of capacitors over batteries. LIC pouch cells were assembled using activated carbon (AC) cathode and hard carbon (HC) + stabilized lithium metal power (SLMP®) anode. Different cathode configurations, various SLMP loadings on HC anode, and two types of separators were investigated to achieve the optimal electrochemical performance of the LIC. Firstly, the cathode binders study suggests that the PTFE binder offers improved energy and power performances for LIC in comparison to PVDF. Secondly, the mass ratio of SLMP to HC is at 1:7 to obtain the optimized electrochemical performance for LIC among all the various studied mass ratios between lithium loading amounts and active anode material. Finally, compared to the separator Celgard PP 3501, cellulose based TF40-30 is proven to be a preferred separator for LIC.

Achievement motivation and memory: achievement goals differentially influence immediate and delayed remember-know recognition memory.

Science.gov (United States)

Murayama, Kou; Elliot, Andrew J

2011-10-01

Little research has been conducted on achievement motivation and memory and, more specifically, on achievement goals and memory. In the present research, the authors conducted two experiments designed to examine the influence of mastery-approach and performance-approach goals on immediate and delayed remember-know recognition memory. The experiments revealed differential effects for achievement goals over time: Performance-approach goals showed higher correct remember responding on an immediate recognition test, whereas mastery-approach goals showed higher correct remember responding on a delayed recognition test. Achievement goals had no influence on overall recognition memory and no consistent influence on know responding across experiments. These findings indicate that it is important to consider quality, not just quantity, in both motivation and memory, when studying relations between these constructs.

Achievement goal profiles and developments in effort and achievement in upper elementary school.

Science.gov (United States)

Hornstra, Lisette; Majoor, Marieke; Peetsma, Thea

2017-12-01

The multiple goal perspective posits that certain combinations of achievement goals are more favourable than others in terms of educational outcomes. This study aimed to examine longitudinally whether students' achievement goal profiles and transitions between profiles are associated with developments in self-reported and teacher-rated effort and academic achievement in upper elementary school. Participants were 722 fifth-grade students and their teachers in fifth and sixth grade (N = 68). Students reported on their achievement goals and effort in language and mathematics three times in grade 5 to grade 6. Teachers rated students' general school effort. Achievement scores were obtained from school records. Goal profiles were derived with latent profile and transition analyses. Longitudinal multilevel analyses were conducted. Theoretically favourable goal profiles (high mastery and performance-approach goals, low on performance-avoidance goals), as well as transitions from less to more theoretically favourable goal profiles, were associated with higher levels and more growth in effort for language and mathematics and with stronger language achievement gains. Overall, these results provide support for the multiple goal perspective and show the sustained benefits of favourable goal profiles beyond effects of cognitive ability and background characteristics. © 2017 The Authors. British Journal of Education Psychology published by John Wiley & Sons Ltd on behalf of British Psychological Society.

A near one-dimensional 2-shock indirectly driven implosion at convergence ratio 30

Science.gov (United States)

MacLaren, Steve

2017-10-01

Inertial confinement fusion implosions at the National Ignition Facility, while successfully demonstrating self-heating due to alpha-particle deposition, have fallen short of the performance predicted by one-dimensional multi-physics implosion simulations. The current understanding, based on simulations as well as experimental evidence, suggests that the principle reason for the disagreement is a breeching of the cold fuel assembly at stagnation which would otherwise completely confine the hot spot. 3-D simulations indicate a combination of low-mode symmetry swings and ablation-front hydrodynamic instability seeded by engineering features such as the capsule tent and fill tube lead to localized thinning and perforation of the stagnated fuel, resulting in a loss of hot spot pressure and energy. We describe a short series of experiments on the NIF designed specifically to avoid these issues in order to understand if, once they are removed, a suspended-fuel-layer deuterium-tritium implosion can achieve 1-D simulated performance. The particular implosion system combines a thick capsule shell with an elevated initial ablation temperature to minimize the ablation front perturbations from the engineering features, and incorporates a large ratio of hohlraum-to-capsule radius as a means to permit a higher degree of control over implosion symmetry. The resulting implosion at a convergence ratio of 30 was not perfectly spherically symmetric as observed by both neutron and time-resolved x-ray imaging diagnostics. However, the stagnation observables match closely the performance predicted by 1D simulations, including, when some hot spot motion is accounted for, the apparent ion temperature. We present this result along with the design for an upcoming 2-shock experiment to test whether this level of agreement with the 1D model can be achieved in the self-heating regime. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under

Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome.

Directory of Open Access Journals (Sweden)

Pan Ji

Full Text Available A unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing. To examine its composition and the factors that shape it, standardized cold water plumbing rigs were deployed at the treatment plant and in the distribution system of five water utilities across the U.S. Three pipe materials (copper with lead solder, CPVC with brass fittings or copper/lead combined pipe were compared, with 8 hour flush cycles of 10 minutes to simulate typical daily use patterns. High throughput Illumina sequencing of 16S rRNA gene amplicons was employed to profile and compare the resident bulk water bacteria and archaea. The utility, location of the pipe rig, pipe material and stagnation all had a significant influence on the plumbing microbiome composition, but the utility source water and treatment practices were dominant factors. Examination of 21 water chemistry parameters suggested that the total chlorine concentration, pH, P, SO42- and Mg were associated with the most of the variation in bulk water microbiome composition. Disinfectant type exerted a notably low-magnitude impact on microbiome composition. At two utilities using the same source water, slight differences in treatment approaches were associated with differences in rare taxa in samples. For genera containing opportunistic pathogens, Utility C samples (highest pH of 9-10 had the highest frequency of detection for Legionella spp. and lowest relative abundance of Mycobacterium spp. Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.

Neutronics performances study of silicon carbide as an inert matrix to achieve very high burn-up for light water reactor fuels

International Nuclear Information System (INIS)

Chabert, C.; Coulon-Picard, E.; Pelletier, M.

2007-01-01

In order to extend the actual limits of light water reactors, the Cea has put emphasis on the exploration of major fuel innovations that would allow us to increase the competitiveness, the safety and flexibility, while keeping the standard PWR environment. Different fuel concepts have been chosen and are actually studied to evaluate their advantages and drawbacks. The objectives of these new fuels are to increase the safety performances and to achieve a very high burn-up. One concept is a CERCER fuel with silicon carbide (SiC) as an inert matrix devoted to reduce the fuel temperature at nominal conditions. Besides the investigation of the neutronic performance, analyses on the thermomechanical performances, the fuel fabrication, the fuel reprocessing and economic aspects have been performed. This paper presents particularly neutronic results obtained for the CERCER fuel. The results show that a very high burn-up, a high safety performance and a better competitiveness cannot be achieved with this fuel concept. (authors)

A Critical Pragmatism: Marcuse, Adorno, and Peirce on the Artificial Stagnation of Individual and Social Development in Advanced Industrial Societies

Directory of Open Access Journals (Sweden)

Clancy Smith

2009-12-01

Full Text Available This paper will analyze the effects advanced industrial societies have on individual and social development through the eyes of Marcuse’s One-Dimensional Man and the moral consequences of such artificial stagnation through Adorno’s lectures on The Problems of Moral Philosophy. Because such an investigation necessarily brings us into the realm of social psychology, we will turn to the social psychological tradition at the heart of American pragmatism, a target for critical theorists who are often antagonistic to the entire tradition. We will endeavor to advance two alternate readings of the work of C.S. Peirce, arguing that although one type of pragmatism may be justly attacked by critical theorists, there is another, I argue, more critical manifestation of pragmatic human development, that requires the type of autonomy-infused, open-ended development that Marcuse champions. Moreover, I will argue that Peirce’s seminal essay “The Fixation of Belief” anticipated many of Marcuse’s critiques of advanced industrial societies by nearly ninety years.

Craft-Joule Project: Stagnation proof transparently insulated flat plate solar collector (static)

Energy Technology Data Exchange (ETDEWEB)

Oliva, A; Cadafalch, J; Perez-Segarra, C.D. [Universitat Politecnica de Catalunya, Barcelona (Spain)] (and others)

2000-07-01

The STATIC (STAgnation proof Transparently Insulated flat plate Solar Collector) project is a Craft-Joule Project within the framework of the Non Nuclear Energy Programme Joule III coordinated by the Centre Technologic de Transferencia de Calor (CTTC). The core group of SMEs involved in the project has its main economical activity in the field of solar thermal systems at low temperature level (domestic hot water, solar heating, etc.). Beyond this, a large application potential exists for solar heating at medium temperature level (from 80 to 160 Celsius degrees) : industrial process heat, solar cooling and air conditioning, solar drying , distillation and desalination. Three of the four SME proposers are located in Southern Europe and in the Caribean, where a continuos increase of the demand for air conditioning and cooling has been demonstrated in the last years. The recent development of flat plate solar collectors with honeycomb-type transparent insulation cover has shown that this type of collectors can become a low cost alternative to evacuated tube and high concentrating CPC collectors in the medium temperature range from 80 to 160 Celsius degrees. With the expected reduction of collector cost, that forms 30%-50% of total system cost, a decisive break-through of solar thermal systems using heat in the medium temperature range can be achieved. The feasibility and good performance of these solar collectors has been proved in several prototypes. Nevertheless, up to now no commercial products are available. In order to reach this, the following developments of new concepts are necessary and are being carried out within this project: solution of the problem of overheating: development of collector versions for different working temperatures: optimization of the design with the support of high level numerical simulation. Several prototypes of the new solar collectors are being tested. System tests will also be carried or for two test arrays of optimized collector

Racial and Social Class Differences in How Parents Respond to Inadequate Achievement: Consequences for Children's Future Achievement.

Science.gov (United States)

Robinson, Keith; Harris, Angel L

2013-12-01

Despite numerous studies on parental involvement in children's academic schooling, there is a dearth of knowledge on how parents respond specifically to inadequate academic performance. This study examines whether 1) racial differences exist in parenting philosophy for addressing inadequate achievement, 2) social class has implications for parenting philosophy, and 3) parents' philosophies are consequential for children's academic achievement. Using data from the Child Development Supplement (N=1041) to the Panel Study of Income Dynamics, we sort parents into two categories-those whose parenting repertoires for addressing poor achievement include punitive responses and those whose repertoires do not. We then determine whether racial differences exist between these categories and how various responses within the aforementioned categories are related to students' academic achievement. The findings show that white and black parents have markedly different philosophies on how to respond to inadequate performance, and these differences appear to impact children's achievement in dramatically different ways. Educators and policy makers should pay particular attention to how parents respond to inadequate achievement as imploring parents of inadequately performing students to be more involved without providing them with some guidance might exacerbate the problem.

Effects and mechanisms of Shaofu-Zhuyu decoction and its major bioactive component for Cold - Stagnation and Blood - Stasis primary dysmenorrhea rats.

Science.gov (United States)

Huang, Xiaochen; Su, Shulan; Duan, Jin-Ao; Sha, Xiuxiu; Zhu, Kavin Yue; Guo, Jianming; Yu, Li; Liu, Pei; Shang, Erxin; Qian, Dawei

2016-06-20

Traditional Chinese medicine (TCM) is used under the guidance of the theory of traditional Chinese medical sciences in clinical application. The Chinese herbal formula, Shaofu Zhuyu decoction (SFZYD), is considered as an effective prescription for treating Cold - Stagnation and Blood - Stasis (CSBS) primary dysmenorrhea. The previous studies showed the SFZYD exhibited significant anti-inflammation and analgesic effect. In this present study the metabolomics of CSBS primary dysmenorrhea diseased rats and the cytokine transcription in PHA stimulated-PBMC were investigated to explore the effects and mechanisms. Explore a valuable insight into the effects and mechanisms of SFZYD on Cold - Stagnation and Blood - Stasis primary dysmenorrhea rats. We established CSBS primary dysmenorrhea diseased rats according the clinical symptoms. A targeted tandem mass spectrometry (MS/MS)-based metabolomic platform was used to evaluate the metabolic profiling changes and the intervention effects by SFZYD. The PBMC cell was adopted to explore the mechanisms by analyzing the signaling pathway evaluated by expression of inflammatory cytokines, c-jun and c-fos and corresponding phosphorylation levels. Estradiol, oxytocin, progesterone, endothelin, β-endorphin and PGF2α were restored back to the normal level after the treatment of SFZYD. Total twenty-five metabolites (10 in plasma and 15 in urine), up-regulated or down-regulated, were identified. These identified biomarkers underpinning the metabolic pathway including pentose and glucuronate interconversions, steroid hormone biosynthesis, and glycerophospholipid metabolism are disturbed in model rats. Among these metabolites, twenty one potential biomarkers were regulated after SFZYD treated. The compound of paeoniflorin, a major bioactive compound in SFZYD, was proved to regulate the MAPK signaling pathway by inhibiting the expression of IL-1β, IL-2, IL-10, IL-12, TNFα, INFγ, c-jun and c-fos in PHA stimulated-PBMC. These findings

Extending Antecedents of Achievement Goals: The Double-Edged Sword Effect of Social-Oriented Achievement Motive and Gender Differences

Science.gov (United States)

Nie, Youyan; Liem, Gregory Arief D.

2013-01-01

Underpinned by the hierarchical model of approach and avoidance motivation, the study examined the differential relations of individual-oriented and social-oriented achievement motives to approach and avoidance achievement goals (mastery-approach, performance-approach, mastery-avoidance, performance-avoidance). A total of 570 Chinese high school…

MHD stagnation point flow and heat transfer of a nanofluid over a permeable nonlinear stretching/shrinking sheet with viscous dissipation effect

Science.gov (United States)

Jusoh, Rahimah; Nazar, Roslinda

2018-04-01

The magnetohydrodynamic (MHD) stagnation point flow and heat transfer of an electrically conducting nanofluid over a nonlinear stretching/shrinking sheet is studied numerically. Mathematical modelling and analysis are attended in the presence of viscous dissipation. Appropriate similarity transformations are used to reduce the boundary layer equations for momentum, energy and concentration into a set of ordinary differential equations. The reduced equations are solved numerically using the built in bvp4c function in Matlab. The numerical and graphical results on the effects of various parameters on the velocity and temperature profiles as well as the skin friction coefficient and the local Nusselt number are analyzed and discussed in this paper. The study discovers the existence of dual solutions for a certain range of the suction parameter. The conducted stability analysis reveals that the first solution is stable and feasible, while the second solution is unstable.

Large amplitude oscillation of a boiling bubble growing at a wall in stagnation flow

International Nuclear Information System (INIS)

Geld, C.W.M. van der; Berg, R. van de; Peukert, P.

2009-01-01

A boiling bubble is created on an artificial site that is part of a bubble generator that is mounted at the center of a pipe. Downflow of water impinges on the bubble generator and creates a stagnation flow above the artificial cavity. Stable axisymmetric elongation in the direction away from the wall and multiple shape oscillation cycles are observed. The time of growth and attachment is typically of the order of 250 ms. Amongst the length scales that characterize the bubble shape is the radius of curvature of the upper part of the bubble, R. The period of oscillation, T, is strongly dependent on time, as is R. The parameters C and m in the defining equation T = C R m √(ρL/σ) have been determined by fitting to data of more than 100 bubbles. For each operating condition, the same values of C and m have been found. The value of m is 1.49 ± 0.02, which is explained from the continuous growth of the bubble and from the relation to the period of oscillation of a free bubble deforming in the fundamental mode corresponding to the third Legendre Polynomial. For the latter, R is the radius of the volume-equivalent sphere, R 0 , and C is √12, while for attached boiling bubbles C is found to amount 1.9√12. The difference is easily explained from the continuous growth, difference in definition, finite amplitude oscillation and proximity of the wall. (author)

Large amplitude oscillation of a boiling bubble growing at a wall in stagnation flow

Energy Technology Data Exchange (ETDEWEB)

Geld, C.W.M. van der; Berg, R. van de; Peukert, P. [Eindhoven University of Technology, Eindhoven (Netherlands). Faculty of Mechanical Engineering], e-mail: C.W.M._v.d.Geld@tue.nl

2009-07-01

A boiling bubble is created on an artificial site that is part of a bubble generator that is mounted at the center of a pipe. Downflow of water impinges on the bubble generator and creates a stagnation flow above the artificial cavity. Stable axisymmetric elongation in the direction away from the wall and multiple shape oscillation cycles are observed. The time of growth and attachment is typically of the order of 250 ms. Amongst the length scales that characterize the bubble shape is the radius of curvature of the upper part of the bubble, R. The period of oscillation, T, is strongly dependent on time, as is R. The parameters C and m in the defining equation T = C R{sup m} {radical}({rho}L/{sigma}) have been determined by fitting to data of more than 100 bubbles. For each operating condition, the same values of C and m have been found. The value of m is 1.49 {+-} 0.02, which is explained from the continuous growth of the bubble and from the relation to the period of oscillation of a free bubble deforming in the fundamental mode corresponding to the third Legendre Polynomial. For the latter, R is the radius of the volume-equivalent sphere, R{sub 0}, and C is {radical}12, while for attached boiling bubbles C is found to amount 1.9{radical}12. The difference is easily explained from the continuous growth, difference in definition, finite amplitude oscillation and proximity of the wall. (author)

Achieving Performance Speed-up in FPGA Based Bit-Parallel Multipliers using Embedded Primitive and Macro support

Directory of Open Access Journals (Sweden)

Burhan Khurshid

2015-05-01

Full Text Available Modern Field Programmable Gate Arrays (FPGA are fast moving into the consumer market and their domain has expanded from prototype designing to low and medium volume productions. FPGAs are proving to be an attractive replacement for Application Specific Integrated Circuits (ASIC primarily because of the low Non-recurring Engineering (NRE costs associated with FPGA platforms. This has prompted FPGA vendors to improve the capacity and flexibility of the underlying primitive fabric and include specialized macro support and intellectual property (IP cores in their offerings. However, most of the work related to FPGA implementations does not take full advantage of these offerings. This is primarily because designers rely mainly on the technology-independent optimization to enhance the performance of the system and completely neglect the speed-up that is achievable using these embedded primitives and macro support. In this paper, we consider the technology-dependent optimization of fixed-point bit-parallel multipliers by carrying out their implementations using embedded primitives and macro support that are inherent in modern day FPGAs. Our implementation targets three different FPGA families viz. Spartan-6, Virtex-4 and Virtex-5. The implementation results indicate that a considerable speed up in performance is achievable using these embedded FPGA resources.

Participation and Performance Reporting for the Alternate Assessment Based on Modified Achievement Standards (AA-MAS). Technical Report 58

Science.gov (United States)

Albus, Deb; Thurlow, Martha L.; Lazarus, Sheryl S.

2011-01-01

This report examines publicly reported participation and performance data for the alternate assessment based on modified achievement standards (AA-MAS). The authors' analysis of these data included all states publicly reporting AA-MAS data, regardless of whether they had received approval to use the results for Title I accountability calculations.…

Stable isotopic fractionation, climate change and episodic stagnation in the eastern Mediterranean during the late Quaternary

Energy Technology Data Exchange (ETDEWEB)

Vergnaud-Grazzini, C [Laboratoire de Geologie Dynamique, Paris (France); Ryan, W B.F. [Columbia Univ., Palisades, NY (USA). Lamont-Doherty Geological Observatory; Cita, M B [Milan Univ. (Italy)

1977-11-01

Fluctuations in the delta/sup 18/O composition of planktonic foraminifers in eastern Mediterranean piston cores indicate cycles with amplitudes much greater than those which can be attributed alone to global ice-volume changes. Isotopic values become markedly negative within lithostratigraphic levels characterized by the apparition of organic-rich sapropels. These owe their origin to the development of euxinic bottom water during episodes of basin-wide stagnation. The depletion of delta/sup 18/O in many of the sapropels is accompanied by the occurrence of poorly diversified planktonic faunas, and both phenomena are attributed to a strong dilution of the local eastern Mediterranean surface water mass by a combination of glacial run off from large continental ice sheets and by an important increase of regional precipitation synchronous with the transition from pleniglacial to kataglacial climate. Although sapropel accumulation occurs generally during intervals of warming of the Mediterranean region as determined from a quantitative evaluation of planktonic foraminiferal assemblages, the pre-125,000 years, local warming of eastern Mediterranean surface water lagged the acme of glacial melting by up to 15,000 years. Climatic and isotopic cycles are correlative within the eastern Mediterranean for lateral distances in excess of 1000 km and, except for amplitude and phase, they are in most aspects remarkably similar to those recorded in the equatorial Pacific and Caribbean.

Unsteady separated stagnation-point flow and heat transfer of a viscous fluid over a moving flat surface

Science.gov (United States)

Dholey, S.

2018-04-01

In this paper, we have investigated numerically the laminar unsteady separated stagnation-point flow and heat transfer of a viscous fluid over a moving flat surface in the presence of a time dependent free stream velocity which causes the unsteadiness of this flow problem. The plate is assumed to move in the same or opposite direction of the free stream velocity. The flow is therefore governed by the velocity ratio parameter λ (ratio of the plate velocity to the free stream velocity) and the unsteadiness parameter β. When the plate surface moves in the same direction of the free stream velocity (i.e., when λ > 0), the solution of this flow problem continues for any given value of β. On the other hand, when they move in opposite directions (i.e., when λ heat transfer analysis is that for a given value of λ(= 0), first the heat transfer rate increases with the increase of the Prandtl number Pr and after attaining a maximum value, it decreases and finally tends to be zero for large values of Pr depending upon the values of β > 0. On the contrary, for a given value of β(≤ 0), the rate of heat transfer increases consistently with the increase of Pr.

Mixed convection stagnation-point flow of nanofluids over a stretching/shrinking sheet in a porous medium with internal heat generation/absorption

Directory of Open Access Journals (Sweden)

Dulal Pal

2015-05-01

Full Text Available In this paper, we analyzed the buoyancy-driven radiative non-isothermal heat transfer in a nanofluid stagnation-point flow over a stretching/shrinking sheet embedded in a porous medium.The effects of thermal radiation and internal heat generation/absorption along with suction/injection at the boundary are also considered. Three different types of nanofluids, namely the Copper-water, the Alumina-water and the Titanium dioxide water are considered. The resulting coupled nonlinear differential equations are solved numerically by a fifth-order Runge-Kutta-Fehlberg integration scheme with a shooting technique. A good agreement is found between the present numerical results and the available results in the literature for some special cases. The effects of the physical parameters on the flow and temperature characteristics are presented through tables and graphs, and the salient features are discussed. The results obtained reveal many interesting behaviors that warrant further study on the heat transfer enhancement due to the nanofluids.

Spin Transition in the Lower Mantle: Deep Learning and Pattern Recognition of Superplumes from the Mid-mantle and Mid-mantle Slab Stagnation

Science.gov (United States)

Yuen, D. A.; Shahnas, M. H.; De Hoop, M. V.; Pysklywec, R.

2016-12-01

The broad, slow seismic anomalies under Africa and Pacific cannot be explained without ambiguity. There is no well-established theory to explain the fast structures prevalent globally in seismic tomographic images that are commonly accepted to be the remnants of fossil slabs at different depths in the mantle. The spin transition from high spin to low spin in iron in ferropericlase and perovskite, two major constituents of the lower mantle can significantly impact their physical properties. We employ high resolution 2D-axisymmetric and 3D-spherical control volume models to reconcile the influence of the spin transition-induced anomalies in density, thermal expansivity, and bulk modulus in ferropericlase and perovskite on mantle dynamics. The model results reveal that the spin transition effects increase the mixing in the lower regions of mantle. Depending on the changes of bulk modulus associated with the spin transition, these effects may also cause both stagnation of slabs and rising plumes at mid-mantle depths ( 1600 km). The stagnation may be followed by downward or upward penetration of cold or hot mantle material, respectively, through an avalanche process. The size of these mid-mantle plumes reaches 1500 km across with a radial velocity reaching 20 cm/yr near the seismic transition zone and plume heads exceeding 2500 km across. We will employ a deep-learning algorithm to formulate this challenge as a classification problem where modelling/computation aids in the learning stage for detecting the particular patterns.The parameters based on which the convection models are developed are poorly constrained. There are uncertainties in initial conditions, heterogeneities and boundary conditions in the simulations, which are nonlinear. Thus it is difficult to reconstruct the past configuration over long time scales. In order to extract information and better understand the parameters in mantle convection, we employ deep learning algorithm to search for different

Cryogenics system: strategy to achieve nominal performance and reliable operation

International Nuclear Information System (INIS)

Bremer, J.; Brodzinski, K.; Casas, J.; Claudet, S.; Delikaris, D.; Delruelle, N.; Ferlin, G.; Fluder, C.; Perin, A.; Perinic, G.; Pezzetti, M.; Pirotte, O.; Tavian, L.; Wagner, U.

2012-01-01

During the LHC operation in 2010 and 2011, the cryogenic system has achieved an availability level fulfilling the overall requirement. To reach this level, the cryogenic system has profited like many other beam-dependent systems from the reduced beam parameters. Therefore, impacts of some failures occurred during the LHC operation were mitigated by using the over-capacity margin, the existing built-in redundancy in between adjacent sector cryogenic plants and the 'cannibalization' of spares on two idle cryogenic plants. These two first years of operation were also crucial to identify the weaknesses of the present cryogenic maintenance plan and new issues like SEUs. After the LS1, nominal beam parameters are expected and the mitigated measures will be less effective or not applicable at all. Consequently, a consolidation plan to improve the MTBF and the MTTR of the LHC cryogenic system is under definition. Concerning shutdown periods, the present cryogenic sectorization imposes some restrictions in the type of interventions (e.g. cryo-magnet removal) which can be done without affecting the operating conditions of the adjacent sector. This creates additional constrains and possible extra down-time in the schedule of the shutdowns including the hardware commissioning. This presentation focuses on the consolidation plan foreseen during the LS1 to improve the performance of the LHC cryogenic system in terms of availability and sectorization. (authors)

Effects of Gender, Mathematics Anxiety and Achievement Motivation on College Students’ Achievement in Mathematics

Directory of Open Access Journals (Sweden)

Ajogbeje Oke James

2013-07-01

Full Text Available The urge to excel or perform maximally in mathematics varies from individual to individual because achievement motivation is often developed or learnt during socialization and learning experiences. The study examined the relationship between College of Education students’ achievement motivation and mathematics achievement, correlation coefficient between mathematics anxiety and college students’ achievement motivation as well as mathematics anxiety and mathematics achievement. The sample, 268 College of Education students offering mathematics as one of their subject combination, was selected using purposive sampling techniques. Three research instruments namely: Mathematics Anxiety Scale (MAS, Achievement Motivation Scale (AMS and Mathematics Achievement Test (MAT were used to collect data for the study. Data collected for the study were analyzed using correlational analysis and ANOVA. The results showed that a significantly low negative correlation coefficient existed between mathematics anxiety and mathematics achievement. There is a negative and significant correlation coefficient between mathematics anxiety and achievement motivation. Similarly, a positive and significant correlation coefficient also exists between achievement motivation and mathematics achievement. Based on the findings of the study, it was recommended that mathematics teachers should adopt activity based strategies and conducive learning environment in order to reduce college students’ anxieties in mathematics learning.

Quantifying Faculty Productivity in Japan: Development and Application of the Achievement-Motivated Key Performance Indicator. Research & Occasional Paper Series: CSHE.8.16

Science.gov (United States)

Aida, Misako; Watanabe, Satoshi P.

2016-01-01

Universities throughout the world are trending toward more performance based methods to capture their strengths, weaknesses and productivity. Hiroshima University has developed an integrated objective measure for quantifying multifaceted faculty activities, namely the "Achievement-Motivated Key Performance Indicator" (A-KPI), in order to…

Relationships between Learning Styles and Academic Achievement and Brain Hemispheric Dominance and Academic Performance in Business and Accounting Courses.

Science.gov (United States)

Carthey, Joseph H.

A study determined if relationships exist between learning styles and academic achievement and brain hemispheric dominance and academic performance in the courses of principles of management, business law, intermediate accounting, and principles of economics. All second-year accounting students (64 students) at Northeast Iowa Community College…

Metrics, Dollars, and Systems Change: Learning from Washington State's Student Achievement Initiative to Design Effective Postsecondary Performance Funding Policies. A State Policy Brief

Science.gov (United States)

Jenkins, Davis; Shulock, Nancy

2013-01-01

The Student Achievement Initiative (SAI), adopted by the Washington State Board for Community and Technical Colleges in 2007, is one of a growing number of performance funding programs that have been dubbed "performance funding 2.0." Unlike previous performance funding models, the SAI rewards colleges for students' intermediate…

Animation-assisted CPRII program as a reminder tool in achieving effective one-person-CPR performance.

Science.gov (United States)

Choa, Minhong; Cho, Junho; Choi, Young Hwan; Kim, Seungho; Sung, Ji Min; Chung, Hyun Soo

2009-06-01

The objective of this study is to compare the skill retention of two groups of lay persons, six months after their last CPR training. The intervention group was provided with animation-assisted CPRII (AA-CPRII) instruction on their cellular phones, and the control group had nothing but what they learned from their previous training. This study was a single blind randomized controlled trial. The participants' last CPR trainings were held at least six months ago. We revised our CPR animation for on-site CPR instruction content emphasizing importance of chest compression. Participants were randomized into two groups, the AA-CPRII group (n=42) and the control group (n=38). Both groups performed three cycles of CPR and their performances were video recorded. These video clips were assessed by three evaluators using a checklist. The psychomotor skills were evaluated using the ResusciAnne SkillReporter. Using the 30-point scoring checklist, the AA-CPRII group had a significantly better score compared to the control group (pCPR could be used as a reminder tool in achieving effective one-person-CPR performance. By installing the CPR instruction on cellular phones and having taught them CPR with it during the training enabled participants to perform better CPR.

Impression management and achievement motivation:Investigating substantive links

OpenAIRE

Elliot, Andrew J.; Aldhobaiban, Nawal; Murayama, Kou; Kobeisy, Ahmed; Gocłowska, Małgorzata A.; Khyat, Aber

2018-01-01

In the present research we investigate impression management (IM) as a substantive personality variable by linking it to differentiated achievement motivation constructs, namely achievement motives (workmastery, competitiveness, fear of failure) and achievement goals (mastery-approach, mastery-avoidance, performance-approach, performance-avoidance). Study 1 revealed that IM was a positive predictor of workmastery and a negative predictor of competitiveness (with and without self-deceptive enh...

Control-value theory: using achievement emotions to improve understanding of motivation, learning, and performance in medical education: AMEE Guide No. 64.

Science.gov (United States)

Artino, Anthony R; Holmboe, Eric S; Durning, Steven J

2012-01-01

In this AMEE Guide, we consider the emergent theoretical and empirical work on human emotion and how this work can inform the theory, research, and practice of medical education. In the Guide, we define emotion, in general, and achievement emotions, more specifically. We describe one of the leading contemporary theories of achievement emotions, control-value theory (Pekrun 2006), and we distinguish between different types of achievement emotions, their proximal antecedents, and their consequences for motivation, learning, and performance. Next, we review the empirical support for control-value theory from non-medical fields and suggest several important implications for educational practice. In this section, we highlight the importance of designing learning environments that foster a high degree of control and value for students. Finally, we end with a discussion of the need for more research on achievement emotions in medical education, and we propose several key research questions we believe will facilitate our understanding of achievement emotions and their impact on important educational outcomes.

Achieving excellence in training

International Nuclear Information System (INIS)

Mangin, A.M.; Solymossy, J.M.

1983-01-01

Operating a nuclear power plant is a uniquely challenging activity, requiring a high degree of competence from all who are involved. Achieving and maintaining this competence requires excellence in training. But what does excellence mean, and how do we achieve it. Based on the experience gained by INPO in plant training evaluations and accreditation activities, this paper describes some of the actions that can be taken to achieve the quality appropriate for nuclear power plant training. These actions are discussed in relation to the four phases of a performance-based training system: (1) needs analysis, (2) program design and development, (3) implementation, and (4) evaluation and improvement

Achieving optimum diffraction based overlay performance

Science.gov (United States)

Leray, Philippe; Laidler, David; Cheng, Shaunee; Coogans, Martyn; Fuchs, Andreas; Ponomarenko, Mariya; van der Schaar, Maurits; Vanoppen, Peter

2010-03-01

Diffraction Based Overlay (DBO) metrology has been shown to have significantly reduced Total Measurement Uncertainty (TMU) compared to Image Based Overlay (IBO), primarily due to having no measurable Tool Induced Shift (TIS). However, the advantages of having no measurable TIS can be outweighed by increased susceptibility to WIS (Wafer Induced Shift) caused by target damage, process non-uniformities and variations. The path to optimum DBO performance lies in having well characterized metrology targets, which are insensitive to process non-uniformities and variations, in combination with optimized recipes which take advantage of advanced DBO designs. In this work we examine the impact of different degrees of process non-uniformity and target damage on DBO measurement gratings and study their impact on overlay measurement accuracy and precision. Multiple wavelength and dual polarization scatterometry are used to characterize the DBO design performance over the range of process variation. In conclusion, we describe the robustness of DBO metrology to target damage and show how to exploit the measurement capability of a multiple wavelength, dual polarization scatterometry tool to ensure the required measurement accuracy for current and future technology nodes.

Optimized distributed systems achieve significant performance improvement on sorted merging of massive VCF files.

Science.gov (United States)

Sun, Xiaobo; Gao, Jingjing; Jin, Peng; Eng, Celeste; Burchard, Esteban G; Beaty, Terri H; Ruczinski, Ingo; Mathias, Rasika A; Barnes, Kathleen; Wang, Fusheng; Qin, Zhaohui S

2018-06-01

Sorted merging of genomic data is a common data operation necessary in many sequencing-based studies. It involves sorting and merging genomic data from different subjects by their genomic locations. In particular, merging a large number of variant call format (VCF) files is frequently required in large-scale whole-genome sequencing or whole-exome sequencing projects. Traditional single-machine based methods become increasingly inefficient when processing large numbers of files due to the excessive computation time and Input/Output bottleneck. Distributed systems and more recent cloud-based systems offer an attractive solution. However, carefully designed and optimized workflow patterns and execution plans (schemas) are required to take full advantage of the increased computing power while overcoming bottlenecks to achieve high performance. In this study, we custom-design optimized schemas for three Apache big data platforms, Hadoop (MapReduce), HBase, and Spark, to perform sorted merging of a large number of VCF files. These schemas all adopt the divide-and-conquer strategy to split the merging job into sequential phases/stages consisting of subtasks that are conquered in an ordered, parallel, and bottleneck-free way. In two illustrating examples, we test the performance of our schemas on merging multiple VCF files into either a single TPED or a single VCF file, which are benchmarked with the traditional single/parallel multiway-merge methods, message passing interface (MPI)-based high-performance computing (HPC) implementation, and the popular VCFTools. Our experiments suggest all three schemas either deliver a significant improvement in efficiency or render much better strong and weak scalabilities over traditional methods. Our findings provide generalized scalable schemas for performing sorted merging on genetics and genomics data using these Apache distributed systems.

Thermofluidic compression effects to achieve combustion in a low-compression scramjet engine

Science.gov (United States)

Moura, A. F.; Wheatley, V.; Jahn, I.

2017-12-01

The compression provided by a scramjet inlet is an important parameter in its design. It must be low enough to limit thermal and structural loads and stagnation pressure losses, but high enough to provide the conditions favourable for combustion. Inlets are typically designed to achieve sufficient compression without accounting for the fluidic, and subsequently thermal, compression provided by the fuel injection, which can enable robust combustion in a low-compression engine. This is investigated using Reynolds-averaged Navier-Stokes numerical simulations of a simplified scramjet engine designed to have insufficient compression to auto-ignite fuel in the absence of thermofluidic compression. The engine was designed with a wide rectangular combustor and a single centrally located injector, in order to reduce three-dimensional effects of the walls on the fuel plume. By varying the injected mass flow rate of hydrogen fuel (equivalence ratios of 0.22, 0.17, and 0.13), it is demonstrated that higher equivalence ratios lead to earlier ignition and more rapid combustion, even though mean conditions in the combustor change by no more than 5% for pressure and 3% for temperature with higher equivalence ratio. By supplementing the lower equivalence ratio with helium to achieve a higher mass flow rate, it is confirmed that these benefits are primarily due to the local compression provided by the extra injected mass. Investigation of the conditions around the fuel plume indicated two connected mechanisms. The higher mass flow rate for higher equivalence ratios generated a stronger injector bow shock that compresses the free-stream gas, increasing OH radical production and promoting ignition. This was observed both in the higher equivalence ratio case and in the case with helium. This earlier ignition led to increased temperature and pressure downstream and, consequently, stronger combustion. The heat release from combustion provided thermal compression in the combustor, further

Achievement motivation, competitiveness and sports performance in a team of sportsmen soccer players between 14 and 24 years old

Directory of Open Access Journals (Sweden)

Alejo García-Naveira

2011-05-01

Full Text Available In order to identify to what extent competitiveness trait is related to sport performance in soccer, and to what extent the age and sport category can influence these variables, a descriptive cross-sectional study has been developed. The variables age, sport category, sport performance, achievement motivation (Me, motivation to avoid the failure (Mef and competitiveness trait have been assessed in 151 men soccer players (between 14 and 24 y.o. of a Spanish sport club. The results indicated that the sport performance ascends with age. Consequently, a direct relationship between the sport category and the performance has been observed. Me, Mef and competitiveness trait have been associated with the performance and has varied based on the sport category. No correlation between Me, Mef, competitiveness and age of the sportsmen has been found

Has Athletic Performance Reached its Peak?

Science.gov (United States)

Berthelot, Geoffroy; Sedeaud, Adrien; Marck, Adrien; Antero-Jacquemin, Juliana; Schipman, Julien; Saulière, Guillaume; Marc, Andy; Desgorces, François-Denis; Toussaint, Jean-François

2015-09-01

Limits to athletic performance have long been a topic of myth and debate. However, sport performance appears to have reached a state of stagnation in recent years, suggesting that the physical capabilities of humans and other athletic species, such as greyhounds and thoroughbreds, cannot progress indefinitely. Although the ultimate capabilities may be predictable, the exact path for the absolute maximal performance values remains difficult to assess and relies on technical innovations, sport regulation, and other parameters that depend on current societal and economic conditions. The aim of this literature review was to assess the possible plateau of top physical capabilities in various events and detail the historical backgrounds and sociocultural, anthropometrical, and physiological factors influencing the progress and regression of athletic performance. Time series of performances in Olympic disciplines, such as track and field and swimming events, from 1896 to 2012 reveal a major decrease in performance development. Such a saturation effect is simultaneous in greyhound, thoroughbred, and frog performances. The genetic condition, exhaustion of phenotypic pools, economic context, and the depletion of optimal morphological traits contribute to the observed limitation of physical capabilities. Present conditions prevailing, we approach absolute physical limits and endure a continued period of world record scarcity. Optional scenarios for further improvements will mostly depend on sport technology and modification competition rules.

Boundary layer flow of an oldroyd-b fluid in the region of stagnation point over a stretching sheet

International Nuclear Information System (INIS)

Sajid, M.

2012-01-01

The mathematical modeling for the two-dimensional boundary layer flow of an Oldroyd-B fluid is presented. The developed equations are used to discuss the problem of two-dimensional flow in the region of a stagnation point over a stretching sheet. The obtained partial differential equations are reduced to an ordinary differential equation by a suitable transformation. The obtained equation is then solved using a finite difference method. The influence of the pertinent fluid parameters on the velocity is discussed through graphs. The behavior of f (0) is also investigated for the change in parameter values. Our main focus is to discuss the effects of relaxation and retardation time parameters on the velocity components in the x and y directions. In addition to it the skin friction coefficient is evaluated which is a measure of frictional drag at the surface illustrates that the boundary layer thickness decreases due to an increase in the relaxation time constant. The reason is that a higher relaxation time constant give rise to a slower recovery process and as a result the boundary layer thickness grows at a slower rate for a higher value of the relaxation time constant when compared with its lower value. (orig./A.B.)

Power plant and utility performance: how world-record outages are being achieved in the USA

International Nuclear Information System (INIS)

Anon.

1997-01-01

Two record-breaking refuelling outages at power reactors in the USA are described. The first, at Browns Ferry 3 BWR, was accomplished in 19 days 39 minutes - a shorter time than for an General Electric BWR anywhere in the world hitherto. The management attribute this success to planning, personnel and performance. As well as refuelling, inspections and maintenance, major modifications were carried out. These included the completion of the installation of digital feedwater reactor level control and digital feedwater heater level control. The second outage, at South Texas Project 2 BWR, at 17 days 14 hours and 10 minutes was the fastest yet recorded for any US nuclear unit. This achievement is ascribed to excellent outage preparation and scheduling, the superior condition of the plant equipment and teamwork and safety consciousness on behalf of the plant personnel. Finally, brief consideration is given to the nuclear performance recovery programme of Commonwealth Edison and Ontario Hydro Nuclear. (UK)

Unsteady mixed convection flow of a micro-polar fluid near the stagnation point on a vertical surface

Energy Technology Data Exchange (ETDEWEB)

Lok, Y.Y. [Center for Academic Services, Kolej Universiti Teknikal Kebangsaan Malaysia, 75450 Ayer Keroh, Melaka (Malaysia); Amin, N. [Department of Mathematics, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Pop, I. [Faculty of Mathematics, University of Cluj, R-3400 Cluj, CP 253 (Romania)

2006-12-15

The unsteady mixed convection boundary-layer flow of a micro-polar fluid near the region of the stagnation point on a double-infinite vertical flat plate is studied. It is assumed that the unsteadiness is caused by the impulsive motion of the free stream velocity and by sudden increase or sudden decrease in the surface temperature from the uniform ambient temperature. The problem is reduced to a system of non-dimensional partial differential equations, which is solved numerically using the Keller-box method. This method may present well-behaved solutions for the transient (small time) solution and those of the steady-state flow (large time) solution. It was found that there is a smooth transition from the small-time solution (initial unsteady-state flow) to the large-time solution (final steady-state flow). Further, it is shown that for both assisting and opposing cases and a fixed value of the Prandtl number, the reduced steady-state skin friction and the steady-state heat transfer from the wall (or Nusselt number) decrease with the increase of the material parameter. On the other hand, it is shown that with the increase of the Prandtl number and a fixed value of the material parameter, the reduced steady-state skin friction decreases when the flow is assisting and it increases when the flow is opposing. (author)

Social-Emotional Factors Affecting Achievement Outcomes Among Disadvantaged Students: Closing the Achievement Gap.

Science.gov (United States)

Becker, Bronwyn E; Luthar, Suniya S

2002-01-01

Despite concentrated efforts at improving inferior academic outcomes among disadvantaged students, a substantial achievement gap between the test scores of these students and others remains (Jencks & Phillips, 1998; National Center for Education Statistics, 2000a, 2000b; Valencia & Suzuki, 2000). Existing research used ecological models to document social-emotional factors at multiple levels of influence that undermine academic performance. This article integrates ideas from various perspectives in a comprehensive and interdisciplinary model that will inform policy makers, administrators, and schools about the social-emotional factors that act as both risk and protective factors for disadvantaged students' learning and opportunities for academic success. Four critical social-emotional components that influence achievement performance (academic and school attachment, teacher support, peer values, and mental health) are reviewed.

Expressing International Educational Achievement in Terms of U.S. Performance Standards: Linking NAEP Achievement Levels to TIMSS

Science.gov (United States)

Phillips, Gary W.

2007-01-01

Educators, researchers, and policymakers have considerable interest in how the American educational system compares to those in other countries. One major index for comparison is student academic achievement. This paper links the scale of the "National Assessment of Educational Progress" ("NAEP") to the scale of the "Third International…

Transuranics Laboratory, achievements and performance

International Nuclear Information System (INIS)

Gasco, C.; Anton, M. P.

2004-01-01

The Marine and Aquatic Radioecology Group (MARG) was established in 1985 with the main scope of analysing the consequences of the Palomares accident in the adjacent Mediterranean ecosystem. From then on and up to now , this Group has extended its investigations to other European marine environments, such as the Spanish Mediterranean margin, the Artic and the Atlantic. The main research of long-lived radionuclides (plutonium, americium and Cs-137) determining the orography influence, riverine inputs and their geo-chemical associations. This group is currently accomplishing new challenges on the radioecology field such as the development of techniques for transuranics speciation to determine their geo-chemical association to the main sediment compounds. Natural and anthropogenic radionuclides distribution on salt-marsh areas affected by dry-wet periods is being studied as well as the possibilities of fusing crossed techniques for dating recent sediments (pollen, anthropogenic, ''210 Pb, etc). The Laboratory performance description, the procedures used, calculations, challenges and gaps are described in this report. (Author) 22 refs

Mathematics Achievement by Immigrant Children

Directory of Open Access Journals (Sweden)

Gary G. Huang

2000-05-01

Full Text Available In this study, I examined academic achievement of immigrant children in the United States, Canada, England, Australia, and New Zealand. Analyzing data from the Third International Mathematics and Science Study (TIMSS, I gauged the performance gaps relating to the generation of immigration and the home language background. I found immigrant children's math and science achievement to be lower than the others only in England, the U.S., and Canada. Non-English language background was found in each country to relate to poor math and science learning and this disadvantage was stronger among native-born children—presumably children of indigenous groups—than among immigrant children. I also examined the school variation in math performance gaps, using hierarchical linear modeling (HLM to each country's data. The patterns in which language- and generation-related math achievement gaps varied between schools are different in the five countries.

The Predictiveness of Achievement Goals

Directory of Open Access Journals (Sweden)

Huy P. Phan

2013-11-01

Full Text Available Using the Revised Achievement Goal Questionnaire (AGQ-R (Elliot & Murayama, 2008, we explored first-year university students’ achievement goal orientations on the premise of the 2 × 2 model. Similar to recent studies (Elliot & Murayama, 2008; Elliot & Thrash, 2010, we conceptualized a model that included both antecedent (i.e., enactive learning experience and consequence (i.e., intrinsic motivation and academic achievement of achievement goals. Two hundred seventy-seven university students (151 women, 126 men participated in the study. Structural equation modeling procedures yielded evidence that showed the predictive effects of enactive learning experience and mastery goals on intrinsic motivation. Academic achievement was influenced intrinsic motivation, performance-approach goals, and enactive learning experience. Enactive learning experience also served as an antecedent of the four achievement goal types. On the whole, evidence obtained supports the AGQ-R and contributes, theoretically, to 2 × 2 model.

A Multilevel, Longitudinal Analysis of Middle School Math and Language Achievement

Directory of Open Access Journals (Sweden)

Keith Zvoch

2003-07-01

Full Text Available The performance of schools in a large urban school district was examined using achievement data from a longitudinally matched cohort of middle school students. Schools were evaluated in terms of the mean achievement and mean growth of students in mathematics and language arts. Application of multilevel, longitudinal models to student achievement data revealed that 1 school performance varied across both outcome measures in both subject areas, 2 significant proportions of variation were associated with school-to-school differences in performance, 3 evaluations of school performance differed depending on whether school mean achievement or school mean growth in achievement was examined, and 4 school mean achievement was a weak predictor of school mean growth. These results suggest that assessments of school performance depend on choices of how data are modeled and analyzed. In particular, the present study indicates that schools with low mean scores are not always “poor performing” schools. Use of student growth rates to evaluate school performance enables schools that would otherwise be deemed low performing to demonstrate positive effects on student achievement. Implications for state accountability systems are discussed.

Viscous-inviscid interaction using the parabolized Navier-Stokes equations

DEFF Research Database (Denmark)

Filippone, Antonino; Sørensen, Jens Nørkær

1997-01-01

adaptive grid is used.The interaction is achieved by iterative updatingof the boundary conditions, through the wall transpiration concept. The Navier-Stokes equationsare discretized on a semi-staggered grid.Space-marching integration is performed starting from the stagnation streamline ontwo independent......A numerical model for the calculation of incompressible viscous flows past airfoils andwings has been developed. The approach is based on a strong viscous-inviscid coupling of aboundary element method with the Navier-Stokesequations in vorticity-streamfunction formulation.A semi-adaptive or fully...

Personality and achievement motivation : relationship among Big Five domain and facet scales, achievement goals, and intelligence

NARCIS (Netherlands)

Bipp, T.; Steinmayr, R.; Spinath, B.

2008-01-01

In the present study we examined the nomological network of achievement motivation and personality by inspecting the relationships between four goal orientations (learning, performance-approach, performance-avoidance, work avoidance), the Big Five personality traits, and intelligence. Within a

Competence with fractions predicts gains in mathematics achievement.

Science.gov (United States)

Bailey, Drew H; Hoard, Mary K; Nugent, Lara; Geary, David C

2012-11-01

Competence with fractions predicts later mathematics achievement, but the codevelopmental pattern between fractions knowledge and mathematics achievement is not well understood. We assessed this codevelopment through examination of the cross-lagged relation between a measure of conceptual knowledge of fractions and mathematics achievement in sixth and seventh grades (N=212). The cross-lagged effects indicated that performance on the sixth grade fractions concepts measure predicted 1-year gains in mathematics achievement (ß=.14, pmathematics achievement did not predict gains on the fractions concepts measure (ß=.03, p>.50). In a follow-up assessment, we demonstrated that measures of fluency with computational fractions significantly predicted seventh grade mathematics achievement above and beyond the influence of fluency in computational whole number arithmetic, performance on number fluency and number line tasks, central executive span, and intelligence. Results provide empirical support for the hypothesis that competence with fractions underlies, in part, subsequent gains in mathematics achievement. Copyright © 2012 Elsevier Inc. All rights reserved.

Assessing the performance of winter footwear using a new maximum achievable incline method.

Science.gov (United States)

Hsu, Jennifer; Li, Yue; Dutta, Tilak; Fernie, Geoff

2015-09-01

More informative tests of winter footwear performance are required in order to identify footwear that will prevent injurious slips and falls on icy conditions. In this study, eight participants tested four styles of winter boots on smooth wet ice. The surface was progressively tilted to create increasing longitudinal and cross-slopes until participants could no longer continue standing or walking. Maximum achievable incline angles provided consistent measures of footwear slip resistance and demonstrated better resolution than mechanical tests. One footwear outsole material and tread combination outperformed the others on wet ice allowing participants to successfully walk on steep longitudinal slopes of 17.5° ± 1.9° (mean ± SD). By further exploiting the methodology to include additional surfaces and contaminants, such tests could be used to optimize tread designs and materials that are ideal for reducing the risk of slips and falls. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

The Reciprocal Relations between Self-Concept, Motivation and Achievement: Juxtaposing Academic Self-Concept and Achievement Goal Orientations for Mathematics Success

Science.gov (United States)

Seaton, Marjorie; Parker, Philip; Marsh, Herbert W.; Craven, Rhonda G.; Yeung, Alexander Seeshing

2014-01-01

Research suggests that motivated students and those with high academic self-concepts perform better academically. Although substantial evidence supports a reciprocal relation between academic self-concept and achievement, there is less evidence supporting a similar relation between achievement goal orientations and achievement. There is also a…

Motivation and performance within a collaborative computer-based modeling task: Relations between student's achievement goal orientation, self-efficiacy, cognitive processing and achievement.

NARCIS (Netherlands)

Sins, Patrick H.M.; van Joolingen, Wouter; Savelsbergh, Elwin R.; van Hout-Wolters, Bernadette

2008-01-01

Purpose of the present study was to test a conceptual model of relations among achievement goal orientation, self-efficacy, cognitive processing, and achievement of students working within a particular collaborative task context. The task involved a collaborative computer-based modeling task. In

Motivation and performance within a collaborative computer-based modeling task: Relations between students' achievement goal orientation, self-efficacy, cognitive processing and achievement

NARCIS (Netherlands)

Sins, P.H.M.; van Joolingen, W.R.; Savelsbergh, E.R.; van Hout-Wolters, B.H.A.M.

2008-01-01

Purpose of the present study was to test a conceptual model of relations among achievement goal orientation, self-efficacy, cognitive processing, and achievement of students working within a particular collaborative task context. The task involved a collaborative computer-based modeling task. In

Phenomenological modeling of turbulence in Z-pinch implosions

International Nuclear Information System (INIS)

Thornhill, J.W.; Whitney, K.G.; Deeney, C.; LePell, P.D.

1994-01-01

A phenomenological investigation into the effects of magnetohydrodynamic (MHD) turbulence on the initial stagnation dynamics of aluminum wire array and argon gas puff Z-pinch implosions is performed. The increases that turbulence produces in the plasma viscosity, heat conductivity, and electrical resistivity are modeled by using multipliers for these quantities in one-dimensional (1-D) MHD calculations. The major effect of these increases is to soften the 1-D implosions by decreasing the densities that are achieved on axis at stagnation. As a consequence, a set of multipliers can be found that reasonably duplicates the average electron temperatures, ion densities, and mass of the K-shell emission region that were measured at stagnation for a variety of Physics International aluminum wire array and argon gas puff experiments. It is determined that the dependence of these measured quantities on the multipliers is weak once a level of enhancement is reached, where agreement between calculations and experiments is attained. The scaling of K-shell yield with load mass for a fixed implosion velocity is then reexamined, and the minimum load mass needed to efficiently produce K-shell emission by thermalization of kinetic energy is calculated for aluminum and argon using this phenomenological soft implosion modeling. The results show an upward shift in the minimum mass by a factor of 6 when compared to the original nonturbulent hard implosion calculations

The correlation between achievement goals, learning strategies, and motivation in medical students.

Science.gov (United States)

Kim, Sun; Hur, Yera; Park, Joo Hyun

2014-03-01

The purpose of this study is to investigate the pursuit of achievement goals in medical students and to assess the relationship between achievement goals, learning strategy, and motivation. Two hundred seventy freshman and sophomore premedical students and sophomore medical school students participated in this study, which used the Achievement Goals Scale and the Self-Regulated Learning Strategy Questionnaire. The achievement goals of medical students were oriented toward moderate performance approach levels, slightly high performance avoidance levels, and high mastery goals. About 40% of the students were high or low in all three achievement goals. The most successful adaptive learners in the areas of learning strategies, motivation, and school achievement were students from group 6, who scored high in both performance approach and mastery goals but low in performance avoidance goals. And goal achievement are related to the academic self-efficacy, learning strategies, and motivation in medical students. In the context of academic achievement, mastery goals and performance approach goals are adaptive goals.

Impression management and achievement motivation: Investigating substantive links.

Science.gov (United States)

Elliot, Andrew J; Aldhobaiban, Nawal; Murayama, Kou; Kobeisy, Ahmed; Gocłowska, Małgorzata A; Khyat, Aber

2018-02-01

In this research, we investigate impression management (IM) as a substantive personality variable by linking it to differentiated achievement motivation constructs, namely achievement motives (workmastery, competitiveness, fear of failure) and achievement goals (mastery-approach, mastery-avoidance, performance-approach, performance-avoidance). Study 1 revealed that IM was a positive predictor of workmastery and a negative predictor of competitiveness (with and without self-deceptive enhancement (SDE) controlled). Studies 2a and 2b revealed that IM was a positive predictor of mastery-approach goals and mastery-avoidance goals (without and, in Study 2b, with SDE controlled). These findings highlight the value of conceptualising and utilising IM as a personality variable in its own right and shed light on the nature of the achievement motive and achievement goal constructs. © 2016 International Union of Psychological Science.

Partnering through Training and Practice to Achieve Performance Improvement

Science.gov (United States)

Lyons, Paul R.

2010-01-01

This article presents a partnership effort among managers, trainers, and employees to spring to life performance improvement using the performance templates (P-T) approach. P-T represents a process model as well as a method of training leading to performance improvement. Not only does it add to our repertoire of training and performance management…

Predictors of Academic Self-Handicapping and Achievement: Examining Achievement Goals, Classroom Goal Structures, and Culture

Science.gov (United States)

Urdan, Tim

2004-01-01

The purposes of this study were to examine the predictors and achievement consequences of academic self-handicapping and to explore cultural variations in the pursuit and effects of performance goals and perceived classroom performance goal structures. Data were collected in 2 consecutive academic years from a diverse sample of high school…

Soret and Dufour effects on convective heat and mass transfer in stagnation-point flow towards a shrinking surface

International Nuclear Information System (INIS)

Bhattacharyya, Krishnendu; Layek, G C; Seth, G S

2014-01-01

A mathematical model is presented to study the Soret and Dufour effects on the convective heat and mass transfer in stagnation-point flow of viscous incompressible fluid towards a shrinking surface. Suitable similarity transformations are used to convert the governing partial differential equations into self-similarity ordinary differential equations that are then numerically solved by shooting method. Dual solutions for temperature and concentration are obtained in the presence of Soret and Dufour effects. Graphical representations of the heat and mass transfer coefficients, the dimensionless thermal and solute profiles for various values of Prandtl number, Lewis number, Soret number and Dufour number are demonstrated. With Soret number the mass transfer coefficient which is related to mass transfer rate increases for both solutions and the heat transfer coefficient (related to heat transfer rate) for both solutions becomes larger with Dufour number. The Prandtl number causes reduction in heat and the mass transfer coefficients and similarly with the Lewis number mass transfer coefficient decreases. Also, double crossing over is found in dual dimensionless temperature profiles for increasing Soret number and in dual dimensionless concentration profiles for the increase in Dufour number. Due to the larger values of Dufour number the thermal boundary layer increases and for Prandtl number increment it decreases; whereas, the solute boundary layer thickness reduces with increasing values of Prandtl number and Lewis number. (paper)

To Master or Perform? Exploring Relations between Achievement Goals and Conceptual Change Learning

Science.gov (United States)

Ranellucci, John; Muis, Krista R.; Duffy, Melissa; Wang, Xihui; Sampasivam, Lavanya; Franco, Gina M.

2013-01-01

Background: Research is needed to explore conceptual change in relation to achievement goal orientations and depth of processing. Aims: To address this need, we examined relations between achievement goals, use of deep versus shallow processing strategies, and conceptual change learning using a think-aloud protocol. Sample and Method:…

Brazilian economic performance since the emergence of the great recession: The effects of income distribution on consumption

Directory of Open Access Journals (Sweden)

Arestis Philip

2016-01-01

Full Text Available After a long period of unstable and low economic activity, Brazil achieved a relatively high economic growth with low inflation from 2004 to 2008, when the world scenario was favourable for the Brazilian trade balance. An incomes policy, focused on real increases in the minimum wage along with a credit boom, led to a decade of high consumption growth rates. High levels of consumption and exports, in turn, induced investment and stimulated manufacturing production, despite the real appreciation of the national currency. However, the Great Recession that emerged after the global financial crisis of 2007/2008 brought challenges to the Brazilian economic performance, with unpleasant consequences for the country’s GDP growth. Consumption, investment and exports have decelerated, despite anti-cyclical macroeconomic policies. In this setting, manufacturing production stagnated and GDP growth slowed down substantially, while imports continued rising considerably. The aim of this paper is to provide an explanation to the slowdown of Brazilian growth rates after the Great Recession. The main hypothesis is that consumption was the main source of effective demand in the country since 2003. However, Brazil has not yet been able to sustain manufacturing and economic growth without a more active government policy to stimulate productive investment.

Achievable Performance of Zero-Delay Variable-Rate Coding in Rate-Constrained Networked Control Systems with Channel Delay

DEFF Research Database (Denmark)

Barforooshan, Mohsen; Østergaard, Jan; Stavrou, Fotios

2017-01-01

This paper presents an upper bound on the minimum data rate required to achieve a prescribed closed-loop performance level in networked control systems (NCSs). The considered feedback loop includes a linear time-invariant (LTI) plant with single measurement output and single control input. Moreover......, in this NCS, a causal but otherwise unconstrained feedback system carries out zero-delay variable-rate coding, and control. Between the encoder and decoder, data is exchanged over a rate-limited noiseless digital channel with a known constant time delay. Here we propose a linear source-coding scheme...

Teaching for Successful Intelligence Raises School Achievement.

Science.gov (United States)

Sternberg, Robert J.; Torff, Bruce; Grigorenko, Elena

1998-01-01

A "successful intelligence" intervention improved school achievement for a group of 225 ethnically diverse third-graders, both on performance assessments measuring analytical, creative, and practical achievements and on conventional multiple-choice memory assessments. Teaching for triarchic thinking facilitates factual recall, because learning…

Case study: Comparison of motivation for achieving higher performance between self-directed and manager-directed aerospace engineering teams

Science.gov (United States)

Erlick, Katherine

"The stereotype of engineers is that they are not people oriented; the stereotype implies that engineers would not work well in teams---that their task emphasis is a solo venture and does not encourage social aspects of collaboration" (Miner & Beyerlein, 1999, p. 16). The problem is determining the best method of providing a motivating environment where design engineers may contribute within a team in order to achieve higher performance in the organization. Theoretically, self-directed work teams perform at higher levels. But, allowing a design engineer to contribute to the team while still maintaining his or her anonymity is the key to success. Therefore, a motivating environment must be established to encourage greater self-actualization in design engineers. The purpose of this study is to determine the favorable motivational environment for design engineers and describe the comparison between two aerospace design-engineering teams: one self-directed and the other manager directed. Following the comparison, this study identified whether self-direction or manager-direction provides the favorable motivational environment for operating as a team in pursuit of achieving higher performance. The methodology used in this research was the case study focusing on the team's levels of job satisfaction and potential for higher performance. The collection of data came from three sources, (a) surveys, (b) researcher observer journal and (c) collection of artifacts. The surveys provided information regarding personal behavior characteristics, potentiality for higher performance and motivational attributes. The researcher journal provided information regarding team dynamics, individual interaction, conflict and conflict resolution. The milestone for performance was based on the collection of artifacts from the two teams. The findings from this study illustrated that whether the team was manager-directed or self-directed does not appear to influence the needs and wants of the

Schooling Background and Academic Academic Achievement of Agricultural Students

Directory of Open Access Journals (Sweden)

N. Jayakumar

2016-05-01

Full Text Available In our society academic achievement is considered as a key criterion to judge one’s total potentiality and capability. Academic achievement is seen as a students’ grade point averages in many academic settings. Academic achievement has become an index of students’ future in this highly competitive world and Agricultural education is no exception.  Hence it becomes necessary to find out the factors that determine better academic performance. In this context the present study had been carried out to find out the possible relationship between schooling background and academic achievement of agriculture students. The students admitted in Adhiparasakthi Agricultural College, Kalavai, Vellore between 1999 and 2009 formed the subjects of the study. Findings of the study revealed that determinants like gender, type of school and stream of education had a significant role in the academic achievement of the students. Medium of instruction in HSC did influence the academic achievement but not significantly. It was also found that students who performed well in their HSC did perform well in their undergraduate programme also. This confirms that previous educational outcomes are the most important indicators of student’s future achievement and schooling background has a significant role in academic achievement of students.

Explorations in achievement motivation

Science.gov (United States)

Helmreich, Robert L.

1982-01-01

Recent research on the nature of achievement motivation is reviewed. A three-factor model of intrinsic motives is presented and related to various criteria of performance, job satisfaction and leisure activities. The relationships between intrinsic and extrinsic motives are discussed. Needed areas for future research are described.

The Achievement Gap: Factors That Influenced the Achievement of Successful Black Students

Science.gov (United States)

Morton, Kwame R., Sr.

2011-01-01

The academic underperformance of Black students when compared to their White peers has confounded educators nationwide. This discrepancy in academic performance commonly referred to as the achievement gap has become a national crisis which has led to one of the most significant educational reforms undertaken in the United States of America in the…

Semiconductor-based Multilayer Selective Solar Absorber for Unconcentrated Solar Thermal Energy Conversion.

Science.gov (United States)

Thomas, Nathan H; Chen, Zhen; Fan, Shanhui; Minnich, Austin J

2017-07-13

Solar thermal energy conversion has attracted substantial renewed interest due to its applications in industrial heating, air conditioning, and electricity generation. Achieving stagnation temperatures exceeding 200 °C, pertinent to these technologies, with unconcentrated sunlight requires spectrally selective absorbers with exceptionally low emissivity in the thermal wavelength range and high visible absorptivity for the solar spectrum. In this Communication, we report a semiconductor-based multilayer selective absorber that exploits the sharp drop in optical absorption at the bandgap energy to achieve a measured absorptance of 76% at solar wavelengths and a low emittance of approximately 5% at thermal wavelengths. In field tests, we obtain a peak temperature of 225 °C, comparable to that achieved with state-of-the-art selective surfaces. With straightforward optimization to improve solar absorption, our work shows the potential for unconcentrated solar thermal systems to reach stagnation temperatures exceeding 300 °C, thereby eliminating the need for solar concentrators for mid-temperature solar applications such as supplying process heat.

Achieving excellence with limited resources

International Nuclear Information System (INIS)

Anson, L.W.; Spinney, R.W.

1985-01-01

The achievement of excellence in safety of nuclear power plant operation is dependent in part upon establishment of a performance-based training program. Developing such a program can be a laborious, time-consuming, and very expensive effort. Conducting job and task analyses, designing course outlines from learning objectives, developing training materials, evaluating program effectiveness and managing the training process and program through the out-years will exhaust any utility's training budget and staff. Because the achievement of excellence implies that training become in part performance-based, the question arises of how best to attain quality training yet still maintain a reasonable budget and staff workload. The answer lies not just in contracting the support necessary but making use of all available resources - training staff, contractor personnel in INPO

An Evaluation of the Performance of the African Peer Review ...

African Journals Online (AJOL)

... corporate governance and socio-economic development. The APRM is thus the main instrument for self monitoring by participating members states. The introduction of APRM, despite its many limitations represents a unique approach to reposition Africa for development and a break off from stagnation and retrogression.

Predicting the Performance and Survival of Islamic Banks in Malaysia to Achieve Growth Sustainability

Directory of Open Access Journals (Sweden)

Mazuin Sapuan Noraina

2017-01-01

Full Text Available In Malaysia, the growth of the Islamic financial industry has increased tremendously in line with the Government’s ambition to make Malaysia as an international hub for Islamic finance since 2010. With the increasing number of foreign players in this industry plus with the increasing demand from domestic and foreign customers would further enhance the possibility for Malaysia to achieve this ambition. Currently, according to the Economic Transformation Programme, 2012 Malaysia is the world’s third largest market for Shariah assets that cover Islamic banks, Takaful, and sukuk. Malaysia as one of the main contributors to the global Islamic financial assets with Islamic assets in Malaysia grew by 23.8% in 2011 from RM350.8bil to RM434.6bil. The issues of predicting the performance and the survival of Islamic Banks in Malaysia become amongst crucial issues in academic research. By employing multi – layer perceptron neural network and pooled regression, we found that total assets/ size of the Islamic banks (GROWTH have high weightage and significantly influence in predicting the performance and the survival of Islamic banks in Malaysia. With the increasing number of Islamic banking institutions in Malaysia, this study can give insight on the sustainability of the Islamic banking system in Malaysia for the benefit of the investors, shareholder and depositors.

Eating the right amount of fish: Inverted U-shape association between fish consumption and cognitive performance and academic achievement in Dutch adolescents

NARCIS (Netherlands)

De Groot, Renate; Ouwehand, Carolijn; Jolles, Jelle

2012-01-01

De Groot, R. H. M., Ouwehand, C., & Jolles, J. (2012). Eating the right amount of fish: Inverted U-shape association between fish consumption and cognitive performance and academic achievement in Dutch adolescents. Prostaglandins, Leukotrienes, and Essential Fatty Acids, 86(3), 113-117.

The relationship of school performance and mental health: Educational achievement as indicator of psychopathology

NARCIS (Netherlands)

Tempelaar, W.M.

2017-01-01

In this thesis we explored the relationship between poor educational achievement and psychopathology. Examining the association between educational achievement and mental health problems and development of psychiatric disorders is important to investigate the potential value of educational

School performance: An IDEB analysis of the seven municipalities in the ABC region

Directory of Open Access Journals (Sweden)

Paulo Sérgio Garcia

2016-08-01

Full Text Available The quality of basic education in Brazil has been monitored, especially by the Basic Education Development Index (Índice de Desenvolvimento da Educação Básica – IDEB, created in 2007. This index combines students’ achievement in the System of Assessment for Basic Education (Sistema de Avaliação da Educação Básica- SAEB for states and, the Brazilian Exam (Prova Brasil for municipalities, with the school flow (taking into account dropout numbers. This study analyzes the IDEB of the seven municipalities in the ABC region, performing multiple comparisons using mixed methodology. It was analyzed the IDEB of each city, regarding the schools’ level of education (Elementary School I and II. It was considered in the analysis, the schools development, with regard to achieving the goals established by the different administrative spheres and by INEP, as well as, the proportion of students who reached the appropriate level in the competences of reading, reading comprehension and the competence of problem solving. At the same time, all the information that contextualized the quantified data was analyzed with school Principals. The results showed gradual and continuous evolution in the index of Elementary School I in municipal and state spheres, and minimal growth or stagnation in Elementary School II. An even harder reality is presented in mathematics learning. At the data contextualization, the absence of positive continuity from the results of Elementary School I, to Elementary School II, was attributed to the characteristics of each segment, such as the number of teachers, the type of treatment given to the student, the methods used, the references shared and accepted, the school organization, and the school management. This data may assist the schools in the qualitative improvement of education in the cities of the region.

Energy thrift and improved performance achieved through novel railway brake discs

International Nuclear Information System (INIS)

Tirovic, Marko

2009-01-01

A disc with radial vanes and circumferential pillars proves to be successful in operation and achieves energy efficiency improvements compared with those of traditional design. Cooling characteristics of this novel design are practically identical to the disc with tangential vanes but the equivalent aerodynamic (air pumping) losses are approximately 50% less. It is shown that these reductions in pumping losses can lead to substantial energy savings in train operations. When developing new designs and/or comparing different railway disc designs, the proposed disc cooling to aerodynamic efficiency ratio (η v ) was found to be a very useful parameter to assess. This 'efficiency ratio' - a ratio of convective power dissipation to aerodynamic power losses can help in achieving adequate balance of cooling efficiency and aerodynamic losses to suit particular application. The use of CFD is of enormous benefit in generating discs that fulfil these demanding requirements, with the spin rig being exceptionally useful for experimental work

The CryoSat Interferometer after 6 years in orbit: calibration and achievable performance

Science.gov (United States)

Scagliola, Michele; Fornari, Marco; De Bartolomei, Maurizio; Bouffard, Jerome; Parrinello, Tommaso

2016-04-01

The main payload of CryoSat is a Ku-band pulse width limited radar altimeter, called SIRAL (Synthetic interferometric radar altimeter). When commanded in SARIn (synthetic aperture radar interferometry) mode, through coherent along-track processing of the returns received from two antennas, the interferometric phase related to the first arrival of the echo is used to retrieve the angle of arrival of the scattering in the across-track direction. In fact, the across-track echo direction can be derived by exploiting the precise knowledge of the baseline vector (i.e. the vector between the two antennas centers of phase) and simple geometry. The end-to-end calibration strategy for the CryoSat interferometer consists on in-orbit calibration campaigns following the approach described in [1]. From the beginning of the CryoSat mission, about once a year the interferometer calibration campaigns have been periodically performed by rolling left and right the spacecraft of about ±0.4 deg. This abstract is aimed at presenting our analysis of the calibration parameters and of the achievable performance of the CryoSat interferometer over the 6 years of mission. Additionally, some further studies have been performed to assess the accuracy of the roll angle computed on ground as function of the aberration (the apparent displacement of a celestial object from its true position, caused by the relative motion of the observer and the object) correction applied to the attitude quaternions, provided by the Star Tracker mounted on-board. In fact, being the roll information crucial to obtain an accurate estimate of the angle of arrival, the data from interferometer calibration campaigns have been used to verify how the application of the aberration correction affects the roll information and, in turns, the measured angle of arrival. [1] Galin, N.; Wingham, D.J.; Cullen, R.; Fornari, M.; Smith, W.H.F.; Abdalla, S., "Calibration of the CryoSat-2 Interferometer and Measurement of Across

Eating the right amount of fish: Inverted U-shape association between fish consumption and cognitive performance, and academic achievement in Dutch adolescents

NARCIS (Netherlands)

De Groot, Renate; Ouwehand, Carolijn; Jolles, Jelle

2012-01-01

De Groot, R. H. M., Ouwehand, C., & Jolles, J. (2011, 2 September). Eating the right amount of fish: Inverted U-shape association between fish consumption and cognitive performance and academic achievement in Dutch adolescents. Poster presented at the the 14th biannual EARLI conference, Exeter,

Achievement Gaps: How Hispanic and White Students in Public Schools Perform in Mathematics and Reading on the National Assessment of Educational Progress. Highlights. NCES 2011-485

Science.gov (United States)

National Center for Education Statistics, 2011

2011-01-01

This report provides a detailed portrait of Hispanic and White academic achievement gaps and how students' performance has changed over time at both the national and state levels. The report presents achievement gaps using reading and mathematics assessment data from the National Assessment of Educational Progress (NAEP) for the 4th- and 8th-grade…

How Does the Science Writing Heuristic Approach Affect Students' Performances of Different Academic Achievement Levels? A Case for High School Chemistry

Science.gov (United States)

Kingir, Sevgi; Geban, Omer; Gunel, Murat

2012-01-01

This study investigates the effects of the Science Writing Heuristic (SWH), known as an argumentation-based science inquiry approach, on Grade 9 students' performance on a post-test in relation to their academic achievement levels. Four intact classes taught by 2 chemistry teachers from a Turkish public high school were selected for the study; one…

Individual Differences in Achievement Goals: A Longitudinal Study of Cognitive, Emotional, and Achievement Outcomes

Science.gov (United States)

Daniels, Lia M.; Haynes, Tara L.; Stupnisky, Robert H.; Perry, Raymond P.; Newall, Nancy E.; Pekrun, Reinhard

2008-01-01

Within achievement goal theory debate remains regarding the adaptiveness of certain combinations of goals. Assuming a multiple-goals perspective, we used cluster analysis to classify 1002 undergraduate students according to their mastery and performance-approach goals. Four clusters emerged, representing different goal combinations: high…

Eating the right amount of fish: Inverted U-shape association between fish consumption and cognitive performance, and academic achievement in Dutch adolescents

NARCIS (Netherlands)

De Groot, Renate; Ouwehand, Carolijn; Jolles, Jelle

2012-01-01

De Groot, R. H. M., Ouwehand, C., & Jolles, J. (2012, May). Eating the right amount of fish: Inverted U-shape association between fish consumption and cognitive performance, and academic achievement in Dutch adolescents. Paper presented at the 10th Congress of the International Society for the Study

Influences on Academic Achievement of Primary School Pupils in Cambodia

Directory of Open Access Journals (Sweden)

Sopheak Song

2012-12-01

Full Text Available Employing education production function approach, this article investigates the influences of school and pupil background factors on academic achievement of primary school pupils in Cambodia. Based on achievement data of 1,080 Grade 6 pupils from one rural and one semi-urban area, the study reveals that school and teacher quality exerts a considerable effect on pupils’ performance. Teachers’ experience and teacher guides are positively correlated with academic achievement, while instructional time loss is significantly associated with poor performance. In light of these results, policies to boost academic achievement of primary school pupils in Cambodia are discussed.

Parental involvement in homework: relations with parent and student achievement-related motivational beliefs and achievement.

Science.gov (United States)

Gonida, Eleftheria N; Cortina, Kai S

2014-09-01

Parental involvement in homework is a home-based type of involvement in children's education. Research and theory suggest that it is beneficial for learning and achievement under certain conditions and for particular groups of individuals. The study examined whether different types of parents' involvement in homework (autonomy support, control, interference, cognitive engagement) (1) are predicted by their mastery and performance goals for their child and their beliefs of the child's academic efficacy, and (2) predict student achievement goal orientations, efficacy beliefs, and achievement. Grade-level differences were also investigated. The sample consisted of 282 elementary school (5th grade) and junior high school students (8th grade) and one of their parents. Surveys were used for data collection. Structural equation modelling was applied for data analysis. (1) Autonomy support during homework was predicted by parent mastery goal, parents' control and interference by their performance goal and perceptions of child efficacy, and cognitive engagement as supplementary to homework by parent perceptions of child efficacy. (2) Parental autonomy support, control, and interference were differentially associated with student mastery and performance goal orientations, whereas parent cognitive engagement was associated with student efficacy beliefs. (3) The structural model was the same for elementary and junior high school students but the latent means for a number of variables were different. Different types of parental involvement in homework were associated with different outcomes with parent autonomy support to be the most beneficial one. © 2014 The British Psychological Society.

Achieving high performance in intermediate temperature direct carbon fuel cells with renewable carbon as a fuel source

International Nuclear Information System (INIS)

Hao, Wenbin; He, Xiaojin; Mi, Yongli

2014-01-01

Highlights: • Bamboo fiber and waste paper were pyrolyzed to generate bamboo carbon and waste paper carbon as anode fuels of IT-DCFC. • Superior cell performance was achieved with the waste paper carbon. • The results suggested the high performance was due to the highest thermal reactivity and the catalytic inherent impurities. • Calcite and kaolinite as inherent impurities favored the thermal decomposition and the electrooxidation of carbon. - Abstract: Three kinds of carbon sources obtained from carbon black, bamboo fiber and waste paper were investigated as anode fuels in an intermediate temperature direct carbon fuel cell. The carbon sources were characterized with X-ray photoelectron spectroscopy, thermal gravimetric analysis, etc. The results indicated that the waste paper carbon was more abundant in calcite and kaolinite, and showed higher thermal reactivity in the intermediate temperature range compared with the other two carbon sources. The cell performance was tested at 650 °C in a hybrid single cell, using Sm 0.20 Ce 0.80 O 2−x as the electrolyte. As a result, the cell fed with waste paper carbon showed the highest performance among the three carbon sources, with a peak power density of 225 mW cm −2 . The results indicated that its inherent impurities, such as calcite and kaolinite, might favor the thermal gasification of renewable carbon sources, which resulted in the enhanced performance of the intermediate temperature direct carbon fuel cell

Simultaneous Laser-induced Fluorescence of Nitric Oxide and Atomic Oxygen in the Hypersonic Materials Environment Test System Arcjet Facility

Science.gov (United States)

Johansen, Craig; Lincoln, Daniel; Bathel, Brett; Inman, Jennifer; Danehy, Paul

2014-01-01

Simultaneous nitric oxide (NO) and atomic oxygen (O) laser induced fluorescence (LIF) experiments were performed in the Hypersonic Materials Environmental Test System (HYMETS) facility at the NASA Langley Research Center. The data serves as an experimental database for validation for chemical and thermal nonequilibrium models used in hypersonic flows. Measurements were taken over a wide range of stagnation enthalpies (6.7 - 18.5 MJ/kg) using an Earth atmosphere simulant with a composition of 75% N2, 20% O2, and 5% Ar (by volume). These are the first simultaneous measurements of NO and O LIF to be reported in literature for the HYMETS facility. The maximum O LIF mean signal intensity was observed at a stagnation enthalpy of approximately 12 MJ/kg while the maximum NO LIF mean signal intensity was observed at a stagnation enthalpy of 6.7 MJ/kg. Experimental results were compared to simple fluorescence model that assumes equilibrium conditions in the plenum and frozen chemistry in the isentropic nozzle expansion (Mach 5). The equilibrium calculations were performed using CANTERA v2.1.1 with 16 species. The fluorescence model captured the correlation in mean O and NO LIF signal intensities over the entire range of stagnation enthalpies tested. Very weak correlations between single-shot O and NO LIF intensities were observed in the experiments at all of the stagnation enthalpy conditions.

The realistic performance achievable with mycobacterial automated culture systems in high and low prevalence settings

Directory of Open Access Journals (Sweden)

Klatser Paul R

2010-04-01

Full Text Available Abstract Background Diagnostic tests are generally used in situations with similar pre-test probability of disease to where they were developed. When these tests are applied in situations with very different pre-test probabilities of disease, it is informative to model the likely implications of known characteristics of test performance in the new situation. This is the case for automated Mycobacterium tuberculosis (MTB liquid culture systems for tuberculosis case detection which were developed and are widely used in low burden settings but are only beginning to be applied on a large scale in high burden settings. Methods Here we model the performance of MTB liquid culture systems in high and low tuberculosis (TB prevalence settings using detailed published data concentrating on the likely frequency of cross-contamination events. Results Our model predicts that as the TB prevalence in the suspect population increases there is an exponential increase in the risk of MTB cross-contamination events expected in otherwise negative samples, even with equivalent technical performance of the laboratories. Quality control and strict cross-contamination measures become increasingly critical as the burden of MTB infection among TB suspects increases. Even under optimal conditions the realistically achievable specificity of these systems in high burden settings will likely be significantly below that obtained in low TB burden laboratories. Conclusions Liquid culture systems can play a valuable role in TB case detection in laboratories in high burden settings, but laboratory workers, policy makers and clinicians should be aware of the increased risks, independent of laboratory proficiency, of cross-contamination events in high burden settings.

Disciplinary climate and student achievement

DEFF Research Database (Denmark)

Sortkær, Bent; Reimer, David

Disciplinary climate has emerged as one of the single most important factors related to student achievement. Using data from the OECD Programme for International Student Assessment (PISA) 2003 for Canada, Denmark, Finland, Iceland, Latvia and Norway we find a significant and nontrivial association...... between the perceived disciplinary climate in the classroom and students’ mathematics performance in Canada, Denmark and Norway. Furthermore we exploit country specific class-size rules in order to single out a subsample with classroom-level data (PISA is sampled by age and not by classes) and find...... that the estimates based on school-level data might underestimate the relationship between disciplinary climate and student achievement. Finally we find evidence for gender differences in the association between disciplinary climate and student achievement that can partly be explained by gender-specific perceptions...

Meeting a Math Achievement Crisis

Science.gov (United States)

Jennings, Lenora; Likis, Lori

2005-01-01

An urban community spotlighted declining mathematics achievement and took some measures, in which the students' performance increased substantially. The Benjamin Banneker Charter Public School in Cambridge, Massachusetts, engaged the entire community and launched the campaign called "Math Everywhere", which changed Benjamin Banneker's…

Achieving world class maintenance status

Energy Technology Data Exchange (ETDEWEB)

Tomlingson, P.D. [Paul D. Tomingson Associates (United States)

2007-08-15

The article written by a management consultant, discusses the art of successful planning and operation of maintenance in mines considering factors such as benchmaking, key performance indices (KPIs) and frequency of procedures which can help achieve 'world class maintenance'. 1 fig.

Achievement Motivation: A Rational Approach to Psychological Education

Science.gov (United States)

Smith, Robert L.; Troth, William A.

1975-01-01

Investigated the achievement motivation training component of psychological education. The subjects were 54 late-adolescent pupils. The experimental training program had as its objectives an increase in academic achievement motivation, internal feelings of control, and school performance, and a reduction of test anxiety. Results indicated…

Mexican business structure between 2003 and 2008: towards the fourth lost decade

Directory of Open Access Journals (Sweden)

Gaspar Núñez R.

2013-01-01

Full Text Available This research examines Mexican firm structure and performance during the years 2003 and 2008, using data from the 2004 and 2009 Economic Census. We find that the poor firm structure of year 2003 is even worst in 2008. Detailed analysis of variables relevant for economic performance and future development, confirms that the period 2001-2010 was indeed a third lost decade, and that the current firm structure makes it impossible to achieve a meaningful economic development for the 2011-2020 decade. Results also confirm one of the main thesis in current literature, namely, that lack of investment in physical capital is one of the main causes of economy stagnation.

Achievement test performance in children conceived by IVF.

Science.gov (United States)

Mains, L; Zimmerman, M; Blaine, J; Stegmann, B; Sparks, A; Ansley, T; Van Voorhis, B

2010-10-01

Long-term follow-up studies of children conceived by IVF are limited. We examine academic performance on standardized tests [Iowa Tests of Basic Skills/Educational Development (ITBS/ITED)] of children conceived by IVF. Parents of children 8-17 years of age at the onset of the study (March 2008) who were conceived by IVF at the University of Iowa Hospitals and Clinics and living in the state of Iowa were contacted by mail. Parents completed questionnaires on their child's health and education and parental education. ITBS/ITED scores from school grades 3-12 were obtained on IVF children and a group of anonymous children matched by grade, year, gender and school district. Scores were analyzed using linear mixed models. Four hundred and ninety-seven couples were contacted. Two hundred and ninety-five couples (463 children) agreed to participate (59.4% of parents), with ITBS/ITED scores available on 423 children (91.4% of participants). IVF children scored higher than the national mean (P divorce and child's BMI. Cryopreservation, length of embryo culture and method of insemination did not affect scores. IVF children scored higher on standardized tests than their matched peers, suggesting that IVF does not have a negative effect on cognitive development. However, long-term follow-up of IVF children is still limited. Further research should be performed on the effect of multiple gestation on academic performance.

Examining the Academic Achievement-Delinquency Relationship Among Southeast Asian Americans.

Science.gov (United States)

Bui, Laura

2018-05-01

The extent to which poor academic achievement is strongly related to delinquency among Southeast Asian Americans (SEAA) remains unclear; reasons are methodological limitations and aggregated findings for Asian Americans, which mask evidence that SEAA have a higher prevalence of criminality and poor academic performance than other Asian American groups. The present study examines the academic achievement-delinquency relationship in a diverse group of 1,214 SEAA using data from the Children of Immigrants Longitudinal Study (CILS). Propensity score matching (PSM) was used to make causal inferences and assess whether poor academic achieving SEAA, after being matched with higher academic achieving SEAA, displayed a higher prevalence of delinquency. Findings showed that, even after matching, poor academic achieving SEAA were still more likely to exhibit delinquent behavior than those who performed academically better. Interventions targeting SEAA communities will need to focus more on improving academic achievement to directly prevent and decrease delinquent behavior.

Impacts of Implosion Asymmetry And Hot Spot Shape On Ignition Capsules

Science.gov (United States)

Cheng, Baolian; Kwan, Thomas J. T.; Wang, Yi-Ming; Yi, S. Austin; Batha, Steve

2017-10-01

Implosion symmetry plays a critical role in achieving high areal density and internal energy at stagnation during hot spot formation in ICF capsules. Asymmetry causes hot spot irregularity and stagnation de-synchronization that results in lower temperatures and areal densities of the hot fuel. These degradations significantly affect the alpha heating process in the DT fuel as well as on the thermonuclear performance of the capsules. In this work, we explore the physical factors determining the shape of the hot spot late in the implosion and the effects of shape on Î+/-particle transport. We extend our ignition theory [1-4] to include the hot spot shape and quantify the effects of the implosion asymmetry on both the ignition criterion and capsule performance. We validate our theory with the NIF existing experimental data Our theory shows that the ignition criterion becomes more restrictive with the deformation of the hot spot. Through comparison with the NIF data, we demonstrate that the shape effects on the capsules' performance become more explicit as the self-heating and yield of the capsules increases. The degradation of the thermonuclear burn by the hot spot shape for high yield shots to date can be as high as 20%. Our theory is in good agreement with the NIF data. This work was performed under the auspices of the U.S. Department of Energy by the Los Alamos National Laboratory under Contract No. W-7405-ENG-36.

A Study of Motivational Influences on Academic Achievement

Science.gov (United States)

Dishon-Berkovits, Miriam

2014-01-01

This study examined the influence of motivation on academic achievement. The theoretical rationale for the study is grounded in bridging two influential yet isolated literatures of motivation: goal setting theory and achievement goal theory. Although it is clear that academic performance should be influenced by assigned learning goals,…

‘High’ achievers? Cannabis access and academic performance

NARCIS (Netherlands)

Marie, O.; Zölitz, U.N.

2015-01-01

This paper investigates how legal cannabis access affects student performance. Identification comes from an exceptional policy introduced in the city of Maastricht which discriminated legal access based on individuals’ nationality. We apply a difference-in-difference approach using administrative

Concurrently adjusting interrelated control parameters to achieve optimal engine performance

Science.gov (United States)

Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

2015-12-01

Methods and systems for real-time engine control optimization are provided. A value of an engine performance variable is determined, a value of a first operating condition and a value of a second operating condition of a vehicle engine are detected, and initial values for a first engine control parameter and a second engine control parameter are determined based on the detected first operating condition and the detected second operating condition. The initial values for the first engine control parameter and the second engine control parameter are adjusted based on the determined value of the engine performance variable to cause the engine performance variable to approach a target engine performance variable. In order to cause the engine performance variable to approach the target engine performance variable, adjusting the initial value for the first engine control parameter necessitates a corresponding adjustment of the initial value for the second engine control parameter.

Hybrid strategy for increasing fusion performance and stagnation pressure in x-ray driven inertially confined fusion implosions on the NIF

Science.gov (United States)

Hurricane, O. A.; Callahan, D. A.; Edwards, M. J.; Casey, D.; Doeppner, T.; Hohenberger, M.; Hinkel, D.; Berzak Hopkins, L.; Le Pape, S.; MacLaren, S.; Masse, L.; Thomas, C.; Zylstra, A.

2017-10-01

Post NIC (2012), more stable and lower convergence implosions were developed and used as part of a `basecamp' strategy to identify obstacles to further performance. From 2013-2015 by probing away from a conservative working implosion in-steps towards conditions of higher velocity and compression, `Fuel Gain' and alpha-heating were obtained. In the process, performance cliffs unrelated to `mix' were identified the most impactful of which were symmetry control of the implosion and hydro seeded by engineering features. From 2015-2017 we focused on mitigating poor symmetry control and engineering improvements on fill-tubes and capsule mounting techniques. The results were more efficient implosions that can obtain the same performance levels as the earlier implosions, but with less laser energy. Presently, the best of these implosions is poised to step into a burning plasma state. Here, we describe the next step in our strategy that involves using the data we've acquired across parameter space to make a step to the largest symmetric implosions that can be fielded on NIF with the energy available. We describe the key principles that form the foundation of this approach. Performed under the auspices of U.S. Dept. of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

‘High’ Achievers? Cannabis Access and Academic Performance

NARCIS (Netherlands)

O. Marie (Olivier); U. Zoelitz (Ulf)

2016-01-01

textabstractThis paper investigates how legal cannabis access affects student performance. Identification comes from an exceptional policy introduced in the city of Maastricht in the Netherlands that discriminated access via licensed cannabis shops based on an individual’s nationality. We apply a

Student Achievement in College Calculus, Louisiana State University 1967-1968.

Science.gov (United States)

Scannicchio, Thomas Henry

An investigation of freshmen achievement in an introductory calculus course was performed on the basis of high school mathematics background to find predictors of college calculus grades. Overall high school academic achievement, overall high school mathematics achievement, number of high school mathematics units, pattern of college preparatory…

Achievement goals in the workplace : Conceptualization, prevalence, profiles, and outcomes

NARCIS (Netherlands)

Van Yperen, Nico W.; Orehek, Edward

2013-01-01

The purpose of the present paper is to discuss an important component of workers' willingness to perform at their jobs, that is, their achievement motivation. More specifically, we will discuss the conceptualization of the four achievement goals from the 2 x 2 achievement goal framework and present

Resilience and Emotional Intelligence: which role in achievement motivation

Directory of Open Access Journals (Sweden)

Paola Magnano

2016-01-01

Full Text Available In the framework of Positive Organizational Behavior, the construct of Psychological Capital identifies four psychological capacities that affect motivation and performance in the workplace: self-efficacy, hope, optimism and resilience. Emotional Intelligence, then, addresses self-regulatory processes of emotions and motivation that enable people to make adjustments to achieve individual, group, and organizational goals; Emotional Intelligence is strongly correlated with individual advancement and success in an organizational setting and with individual performance. Moreover, Emotional Intelligence is considered an antecedent to resilience. The present study aims to investigate the role of resilience and emotional intelligence in achievement motivation, verifying if emotional intelligence mediates the relationship among resilience and achievement motivation. Participants are 488 Italian workers, aged between 18 and 55 years. The findings confirm the significant role played by emotional intelligence on resilience and on motivation to achievement.

A comprehensive approach to decipher biological computation to achieve next generation high-performance exascale computing.

Energy Technology Data Exchange (ETDEWEB)

James, Conrad D.; Schiess, Adrian B.; Howell, Jamie; Baca, Michael J.; Partridge, L. Donald; Finnegan, Patrick Sean; Wolfley, Steven L.; Dagel, Daryl James; Spahn, Olga Blum; Harper, Jason C.; Pohl, Kenneth Roy; Mickel, Patrick R.; Lohn, Andrew; Marinella, Matthew

2013-10-01

The human brain (volume=1200cm3) consumes 20W and is capable of performing > 10^16 operations/s. Current supercomputer technology has reached 1015 operations/s, yet it requires 1500m^3 and 3MW, giving the brain a 10^12 advantage in operations/s/W/cm^3. Thus, to reach exascale computation, two achievements are required: 1) improved understanding of computation in biological tissue, and 2) a paradigm shift towards neuromorphic computing where hardware circuits mimic properties of neural tissue. To address 1), we will interrogate corticostriatal networks in mouse brain tissue slices, specifically with regard to their frequency filtering capabilities as a function of input stimulus. To address 2), we will instantiate biological computing characteristics such as multi-bit storage into hardware devices with future computational and memory applications. Resistive memory devices will be modeled, designed, and fabricated in the MESA facility in consultation with our internal and external collaborators.

Reading Achievement, Attitude toward Reading, and Reading Self-Esteem of Historically Low Achieving Students

Science.gov (United States)

Kaniuka, Theodore S.

2010-01-01

The main purpose of schools is to improve the academic performance of all students and more recently with special regard to those that have historically struggled to meet state achievement goals. In an effort to attain these goals, educators have utilized many approaches including enhancing student self-esteem as a precursor to improving the…

New York: Expanding Time, Increasing Opportunities for Achievement

Science.gov (United States)

Miller, Tiffany D.

2014-01-01

New York is poised to take an important step to improve student achievement by expanding learning time for students attending high-poverty, low-performing schools. Recent district- and state-level investments in expanded learning time--a promising strategy to close achievement and opportunity gaps--will give students more time to learn core…

Mediating effects of motor performance, cardiorespiratory fitness, physical activity, and sedentary behaviour on the associations of adiposity and other cardiometabolic risk factors with academic achievement in children.

Science.gov (United States)

Haapala, Eero A; Lintu, Niina; Eloranta, Aino-Maija; Venäläinen, Taisa; Poikkeus, Anna-Maija; Ahonen, Timo; Lindi, Virpi; Lakka, Timo A

2018-03-09

We investigated the associations of cardiometabolic risk factors with academic achievement and whether motor performance, cardiorespiratory fitness, physical activity, or sedentary behaviour mediated these associations. Altogether 175 children 6-8 years-of-age participated in the study. We assessed body fat percentage (BF%), waist circumference, insulin, glucose, triglycerides, HDL cholesterol, and systolic and diastolic blood pressure, leptin, alanine aminotransferase, and gamma-glutamyltransferase (GGT). Reading fluency, reading comprehension, and arithmetic skills were assessed using standardized tests. Speed/agility, balance, and manual dexterity test results were used to calculate motor performance score and physical activity was assessed by combined heart rate and movement sensor and cardiorespiratory fitness by maximal cycle ergometer test. In boys, BF% was inversely associated with reading fluency (β = -0.262, P = 0.007) and reading comprehension (β = -0.216, P = 0.025). Motor performance mediated these associations. Leptin was inversely related to reading fluency (β = -0.272, P = 0.006) and reading comprehension (β = -0.287, P = 0.003). The inverse association of leptin with reading fluency was mediated by motor performance. In girls, GGT was inversely associated with reading fluency independent of confounders (β = -0.325, P = 0.007). The inverse association of BF% with academic achievement among boys was largely explained by motor performance. Leptin in boys and GGT in girls were inversely associated with academic achievement independent of confounding factors.

Achievement Goals and Achievement Emotions: A Meta-Analysis

Science.gov (United States)

Huang, Chiungjung

2011-01-01

This meta-analysis synthesized 93 independent samples (N = 30,003) in 77 studies that reported in 78 articles examining correlations between achievement goals and achievement emotions. Achievement goals were meaningfully associated with different achievement emotions. The correlations of mastery and mastery approach goals with positive achievement…

Investigation of side wall effects on an inward scramjet inlet at Mach number 8.6

Science.gov (United States)

Rolim, Tiago Cavalcanti

Experimental and computational studies were conducted to evaluate the performance of a scramjet inlet as the side cowl length is changed. A slender inward turning inlet of a total length of 304.8 mm, a span of 50.8 mm with the compression at 11.54 deg and CR = 4.79 was used. The side cowl lengths were of 0, 50.8 and 76.2 mm. The UTA Hypersonic Shock Tunnel facility was used in the reflected mode. The model was instrumented with nine piezoelectric pressure transducers, for static and total pressure measurements. A wedge was mounted at the rear of the inlet in order to accommodate a Pitot pressure rake. The driven tube was instrumented with three pressure transducers. Two of them were used to measure the incident shock wave speed, and a third one was used for stagnation pressure measurements during a test. Furthermore, a Pitot probe was installed below the model in order to measure the impact pressure on each run, this reading along with the driven sensor readings, allowed us for the calculation of freestream properties. During the experiments, nominal stagnation enthalpy of 0.67 MJ/kg and stagnation pressure of 3.67 MPa were achieved. Freestream conditions were Mach number 8.6 and Reynolds number of 1.94 million per m. Test times were 300 - 500 microseconds. Numerical simulations using RANS with the Wilcox K-w turbulence model were performed using ANSYS Fluent. The results from the static pressure measurements presented a good agreement with CFD predictions. Moreover, the uniformity at the inlet exit was achieved within the experimental precision. The experiments showed that the cowl length has a pronounced effect in the pressure distribution on the inlet and a minor effect in the exit flow Mach number. The numerical results confirmed these trends and showed that a complex flow structure is formed in the cowl-ramp corners; a non-uniform transverse shock structure was found to be related to the cowl leading edge position. Cross flow due to the side expansion

Achieving numerical accuracy and high performance using recursive tile LU factorization with partial pivoting

KAUST Repository

Dongarra, Jack

2013-09-18

The LU factorization is an important numerical algorithm for solving systems of linear equations in science and engineering and is a characteristic of many dense linear algebra computations. For example, it has become the de facto numerical algorithm implemented within the LINPACK benchmark to rank the most powerful supercomputers in the world, collected by the TOP500 website. Multicore processors continue to present challenges to the development of fast and robust numerical software due to the increasing levels of hardware parallelism and widening gap between core and memory speeds. In this context, the difficulty in developing new algorithms for the scientific community resides in the combination of two goals: achieving high performance while maintaining the accuracy of the numerical algorithm. This paper proposes a new approach for computing the LU factorization in parallel on multicore architectures, which not only improves the overall performance but also sustains the numerical quality of the standard LU factorization algorithm with partial pivoting. While the update of the trailing submatrix is computationally intensive and highly parallel, the inherently problematic portion of the LU factorization is the panel factorization due to its memory-bound characteristic as well as the atomicity of selecting the appropriate pivots. Our approach uses a parallel fine-grained recursive formulation of the panel factorization step and implements the update of the trailing submatrix with the tile algorithm. Based on conflict-free partitioning of the data and lockless synchronization mechanisms, our implementation lets the overall computation flow naturally without contention. The dynamic runtime system called QUARK is then able to schedule tasks with heterogeneous granularities and to transparently introduce algorithmic lookahead. The performance results of our implementation are competitive compared to the currently available software packages and libraries. For example

Achieving numerical accuracy and high performance using recursive tile LU factorization with partial pivoting

KAUST Repository

Dongarra, Jack; Faverge, Mathieu; Ltaief, Hatem; Luszczek, Piotr R.

2013-01-01

The LU factorization is an important numerical algorithm for solving systems of linear equations in science and engineering and is a characteristic of many dense linear algebra computations. For example, it has become the de facto numerical algorithm implemented within the LINPACK benchmark to rank the most powerful supercomputers in the world, collected by the TOP500 website. Multicore processors continue to present challenges to the development of fast and robust numerical software due to the increasing levels of hardware parallelism and widening gap between core and memory speeds. In this context, the difficulty in developing new algorithms for the scientific community resides in the combination of two goals: achieving high performance while maintaining the accuracy of the numerical algorithm. This paper proposes a new approach for computing the LU factorization in parallel on multicore architectures, which not only improves the overall performance but also sustains the numerical quality of the standard LU factorization algorithm with partial pivoting. While the update of the trailing submatrix is computationally intensive and highly parallel, the inherently problematic portion of the LU factorization is the panel factorization due to its memory-bound characteristic as well as the atomicity of selecting the appropriate pivots. Our approach uses a parallel fine-grained recursive formulation of the panel factorization step and implements the update of the trailing submatrix with the tile algorithm. Based on conflict-free partitioning of the data and lockless synchronization mechanisms, our implementation lets the overall computation flow naturally without contention. The dynamic runtime system called QUARK is then able to schedule tasks with heterogeneous granularities and to transparently introduce algorithmic lookahead. The performance results of our implementation are competitive compared to the currently available software packages and libraries. For example

Relating beliefs in writing skill malleability to writing performance: The mediating role of achievement goals and self-efficacy

Directory of Open Access Journals (Sweden)

Teresa Limpo

2017-10-01

Full Text Available It is well established that students’ beliefs in skill malleability influence their academic performance. Specifically, thinking of ability as an incremental (vs. fixed trait is associated with better outcomes. Though this was shown across many domains, little research exists into these beliefs in the writing domain and into the mechanisms underlying their effects on writing performance. The aim of this study was twofold: to gather evidence on the validity and reliability of instruments to measure beliefs in skill malleability, achievement goals, and self-efficacy in writing; and to test a path-analytic model specifying beliefs in writing skill malleability to influence writing performance, via goals and self-efficacy. For that, 196 Portuguese students in Grades 7-8 filled in the instruments and wrote an opinion essay that was assessed for writing performance. Confirmatory factor analyses supported instruments’ validity and reliability. Path analysis revealed direct effects from beliefs in writing skill malleability to mastery goals (ß = .45; from mastery goals to self-efficacy for conventions, ideation, and self-regulation (ß = .27, .42, and .42, respectively; and from self-efficacy for self-regulation to writing performance (ß = .16; along with indirect effects from beliefs in writing skill malleability to self-efficacy for self-regulation via mastery goals (ß = .19, and from mastery goals to writing performance via self-efficacy for self-regulation (ß = .07. Overall, students’ mastery goals and self-efficacy for self-regulation seem to be key factors underlying the link between beliefs in writing skill malleability and writing performance. These findings highlight the importance of attending to motivation-related components in the teaching of writing.

HOP: Achieving Efficient Anonymity in MANETs by Combining HIP, OLSR, and Pseudonyms

Directory of Open Access Journals (Sweden)

Campos Javier

2011-01-01

Full Text Available Offering secure and anonymous communications in mobile ad hoc networking environments is essential to achieve confidence and privacy, thus promoting widespread adoption of this kind of networks. In addition, some minimum performance levels must be achieved for any solution to be practical and become widely adopted. In this paper, we propose and implement HOP, a novel solution based on cryptographic Host Identity Protocol (HIP that offers security and user-level anonymity in MANET environments while maintaining good performance levels. In particular, we introduce enhancements to the authentication process to achieve Host Identity Tag (HIT relationship anonymity, along with source/destination HIT anonymity when combined with multihoming. Afterward we detail how we integrate our improved version of HIP with the OLSR routing protocol to achieve efficient support for pseudonyms. We implemented our proposal in an experimental testbed, and the results obtained show that performance levels achieved are quite good, and that the integration with OLSR is achieved with a low overhead.

Family Decision-Making Style, Peer Group Affiliation and Prior Academic Achievement as Predictors of the Academic Achievement of African American Students

Science.gov (United States)

Engerman, Kimarie

2006-01-01

A study analyzed family decision-making style, peer group affiliation, and academic achievement in 10th grade as predictors of academic achievement of African American students in 12th grade. Findings indicated that though peer groups were known to influence academic performance, affiliation with learning oriented peers in 10th grade did not…

Social–Emotional Factors Affecting Achievement Outcomes Among Disadvantaged Students: Closing the Achievement Gap

OpenAIRE

Becker, Bronwyn E.; Luthar, Suniya S.

2002-01-01

Despite concentrated efforts at improving inferior academic outcomes among disadvantaged students, a substantial achievement gap between the test scores of these students and others remains (Jencks & Phillips, 1998; National Center for Education Statistics, 2000a, 2000b; Valencia & Suzuki, 2000). Existing research used ecological models to document social–emotional factors at multiple levels of influence that undermine academic performance. This article integrates ideas from various perspecti...

Perceived emotional intelligence, achievement motivation and school performance in conservatory students

OpenAIRE

Laura López Bernad

2013-01-01

The present research inspects the relationship between Perceived Emotional Intelligence (PEI) and achievement motivation in a sample of students (N=57) belonging to the string department at the Conservatorio Profesional de Música and specializing in violin, viola, violoncello and bass violoncello. The evaluation methods were: the Trait Meta-Mood Scale (TMMS-24), to test Perceived Emotional Intelligence, and the Escala Atribucional de Motivación de Logro (EAML, Attributive Motivation Scale) to...

The effect of formative feedback on students achievement in ...

African Journals Online (AJOL)

The effect of formative feedback on students achievement in graphical element of economic curriculum. ... Journal of Educational Foundations ... Students achievement in graphical elements of economics curriculums has been a problem over the years, students have been performing poorly in SSCE (WAEC & NECO).

Information exchange examined : an interpersonal account of achievement goals

NARCIS (Netherlands)

Poortvliet, P.M.

2008-01-01

In this thesis it is argued and demonstrated, that the achievement goals that individuals pursue in achievement situations may crucially influence how they perceive and act in information exchange situations. Notably, whether people are striving to improve their own performance, as compared with

Neuroanatomical Correlates of Performance in a State-Wide Test of Math Achievement

Science.gov (United States)

Wilkey, Eric D.; Cutting, Laurie E.; Price, Gavin R.

2018-01-01

The development of math skills is a critical component of early education and a strong indicator of later school and economic success. Recent research utilizing population-normed, standardized measures of math achievement suggest that structural and functional integrity of parietal regions, especially the intraparietal sulcus, are closely related…

Students' Achievement Goals, Learning-Related Emotions and Academic Achievement

Directory of Open Access Journals (Sweden)

Marko eLüftenegger

2016-05-01

Full Text Available In the present research, the recently proposed 3x2 model of achievement goals is tested and associations with achievement emotions and their joint influence on academic achievement are investigated. The study was conducted with 388 students using the 3x2 Achievement Goal Questionnaire including the six proposed goal constructs (task-approach, task-avoidance, self-approach, self-avoidance, other-approach, other-avoidance and the enjoyment and boredom scales from the Achievement Emotion Questionnaire. Exam grades were used as an indicator of academic achievement. Findings from CFAs provided strong support for the proposed structure of the 3x2 achievement goal model. Self-based goals, other-based goals and task-approach goals predicted enjoyment. Task-approach goals negatively predicted boredom. Task-approach and other-approach predicted achievement. The indirect effects of achievement goals through emotion variables on achievement were assessed using bias-corrected bootstrapping. No mediation effects were found. Implications for educational practice are discussed.

Supplementary material from "Increased SBPase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions"

NARCIS (Netherlands)

Driever, S.M.; Simkin, Andrew J.; Alotaibi, Saqer; Fisk, Stuart J.; Madgwick, Pippa J.; Sparks, Caroline A.; Jones, Huw D.; Lawson, Tracy; Parry, Martin A.J.; Raines, Christine A.

2017-01-01

To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf

Increased sbpase activity improves photosynthesis and grain yield in wheat grown in greenhouse conditions

NARCIS (Netherlands)

Driever, Steven M.; Simkin, Andrew J.; Alotaibi, Saqer; Fisk, Stuart J.; Madgwick, Pippa J.; Sparks, Caroline A.; Jones, Huw D.; Lawson, Tracy; Parry, Martin A.J.; Raines, Christine A.

2017-01-01

To meet the growing demand for food, substantial improvements in yields are needed. This is particularly the case for wheat, where global yield has stagnated in recent years. Increasing photosynthesis has been identified as a primary target to achieve yield improvements. To increase leaf

The Effect of School Improvement Planning on Student Achievement

Science.gov (United States)

Huber, David J.; Conway, James M.

2015-01-01

This study evaluated the hypothesis that schools in Connecticut's Alliance Districts (lowest-performing districts) with higher-quality school improvement plans (SIPs) would have higher levels of student achievement. An exploratory research question evaluated whether SIPs predicted achievement of particular subgroups. SIPs were obtained and scored…

Achieving Mixtures of Ultra-High Performance Concrete

Directory of Open Access Journals (Sweden)

Mircea POPA

2013-07-01

Full Text Available Ultra-High Performance Concrete (UHPC is a relatively new concrete. According to [11] UHPC is that concrete which features compressive strength over C100/115 class. Up to this point standards for this type of concrete were not adopted, although its characteristic strength exceeds those specified in [33]. Its main property is high compressive strength. This provides the possibility of reducing the section of elements (beams or columns made of this type of concrete, while the load capacity remains high. The study consists in blending mixtures of UHPC made of varying proportions of materials. The authors have obtained strengths of up to 160 MPa. The materials used are: Portland cement, silica fume, quartz powder, steel fibers, superplasticiser, sand and crushed aggregate for concrete - andesite.

Ghana's achievement in mathematics in TIMSS 2007 | Mereku ...

African Journals Online (AJOL)

performance on the international benchmarks also improved significantly. The mathematics score, 309, placed Ghana at the 47th position on the overall mathematics achievement results table when the 48 participating countries, which met the TIMSS sampling requirements, were ranked by their mean performances.

On the Achievable Rate of Hardware-Impaired Transceiver Systems

KAUST Repository

Javed, Sidrah

2018-01-15

In this paper, we accurately model the transceiver hardware impairments (HWIs) of multiple-input multiple-output (MIMO) systems considering different HWI stages at transmitter and receiver. The proposed novel statistical model shows that transceiver HWIs transform the transmitted symmetric signal to asymmetric one. Moreover, it shows that the aggregate self-interference has asymmetric characteristics. Therefore, we propose improper Gaussian signaling (IGS) for transmission in order to improve the achievable rate performance. IGS is considered as a general signaling scheme which includes the proper Gaussian signaling (PGS) as a special case. Thus, IGS has additional design parameters which enable it to mitigate the HWI self-interference. As a case study, we analyze the achievable rate performance of single-input multiple-output systems with linear and selection combiner. Furthermore, we optimize the IGS statistical characteristics for interference alignment. This improves the achievable rate performance as compared to the PGS, which is validated through numerical results.

On the Achievable Rate of Hardware-Impaired Transceiver Systems

KAUST Repository

Javed, Sidrah; Amin, Osama; Ikki, Salama S.; Alouini, Mohamed-Slim

2018-01-01

In this paper, we accurately model the transceiver hardware impairments (HWIs) of multiple-input multiple-output (MIMO) systems considering different HWI stages at transmitter and receiver. The proposed novel statistical model shows that transceiver HWIs transform the transmitted symmetric signal to asymmetric one. Moreover, it shows that the aggregate self-interference has asymmetric characteristics. Therefore, we propose improper Gaussian signaling (IGS) for transmission in order to improve the achievable rate performance. IGS is considered as a general signaling scheme which includes the proper Gaussian signaling (PGS) as a special case. Thus, IGS has additional design parameters which enable it to mitigate the HWI self-interference. As a case study, we analyze the achievable rate performance of single-input multiple-output systems with linear and selection combiner. Furthermore, we optimize the IGS statistical characteristics for interference alignment. This improves the achievable rate performance as compared to the PGS, which is validated through numerical results.

Self-Concept Predicts Academic Achievement Across Levels of the Achievement Distribution: Domain Specificity for Math and Reading.

Science.gov (United States)

Susperreguy, Maria Ines; Davis-Kean, Pamela E; Duckworth, Kathryn; Chen, Meichu

2017-09-18

This study examines whether self-concept of ability in math and reading predicts later math and reading attainment across different levels of achievement. Data from three large-scale longitudinal data sets, the Avon Longitudinal Study of Parents and Children, National Institute of Child Health and Human Development-Study of Early Child Care and Youth Development, and Panel Study of Income Dynamics-Child Development Supplement, were used to answer this question by employing quantile regression analyses. After controlling for demographic variables, child characteristics, and early ability, the findings indicate that self-concept of ability in math and reading predicts later achievement in each respective domain across all quantile levels of achievement. These results were replicated across the three data sets representing different populations and provide robust evidence for the role of self-concept of ability in understanding achievement from early childhood to adolescence across the spectrum of performance (low to high). © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Achievement goals, social goals, and motivational regulations in physical education settings.

Science.gov (United States)

Cecchini Estrada, José A; González González-Mesa, Carmen; Méndez-Giménez, Antonio; Fernández-Río, Javier

2011-02-01

This study examined the relationship between achievement and social goals, and explored how both goals affect students' level of informed self-determination in Physical Education. Participants were 395 high school students. Three scales were used to assess achievement, social goals, and motivation. Several hierarchical regression analyses revealed that mastery-approach goals were the greatest contributors to the individuals' levels of self-determination. Achievement and social goals were found to be separate predictors of students' levels of self-determination, and this highlights the importance of separating mastery and performance goals into avoidance and approach profiles. Girls reported significantly higher values than boys on responsibility, relationship, and mastery-avoidance goals, whereas boys scored higher on performance-approach goals. Researchers could use achievement and social goals to study students' motivation and achievement in Physical Education settings.

The Achievement Ideology and Whiteness: "Achieving Whiteness" or "Achieving Middle Class?"

Science.gov (United States)

Allen, Ricky Lee

Over the past few decades, social reproduction theorists have criticized achievement ideology as a dominant and dominating myth that hides the true nature of class immobility. Social reproductionists' primary criticism of achievement ideology is that it blinds the working class, regardless of race or gender, to the possibilities of collective…

Economic policy of the monetary authorities as factor of achievement of abstract financial stability

Directory of Open Access Journals (Sweden)

Tashtamirov M.R.

2016-11-01

Full Text Available this article is devoted to the questions of the crisis phenomena in Russian economy in sector of a monetary and credit system and a role of economic policy of the monetary authorities (Bank of Russia in ensuring financial stability. Short assessment of the main macroeconomic indicators of the country economy is given. The author is describing the actions of economic management regarding monetary control. It is inexpedient that the Central Bank for carrying out the tough restriction policy directed to oppression of economic development and further primitivizing of national economy. It is offered to transform monetary policy for ensuring anti-recessionary actions exiting the stagnating condition.

Relationship Among Achievement Motivation, Self-Esteem, Locus of ...

African Journals Online (AJOL)

The thrust of the study was to examine the relationship among achievement motivation, self-esteem, locus of control and academic performance of university students in a Nigerian University. The purpose was to determine the extent university student\\'s academic performance was influenced by these criterion variables.

Diagnosing implosion performance at the National Ignition Facility (NIF) by means of neutron spectrometry

International Nuclear Information System (INIS)

Frenje, J.A.; Casey, D.T.; Johnson, M. Gatu; Bionta, R.; Bond, E.J.; Caggiano, J.A.; Cerjan, C.; Edwards, J.; Eckart, M.; Fittinghoff, D.N.; Friedrich, S.; Glenzer, S.; Haan, S.; Hatarik, R.; Hatchett, S.; Jones, O.S.; Glebov, V.Yu.; Knauer, J.P.; Grim, G.; Kilkenny, J.D.

2013-01-01

The neutron spectrum from a cryogenically layered deuterium–tritium (dt) implosion at the National Ignition Facility (NIF) provides essential information about the implosion performance. From the measured primary-neutron spectrum (13–15 MeV), yield (Y n ) and hot-spot ion temperature (T i ) are determined. From the scattered neutron yield (10–12 MeV) relative to Y n , the down-scatter ratio, and the fuel areal density (ρR) are determined. These implosion parameters have been diagnosed to an unprecedented accuracy with a suite of neutron-time-of-flight spectrometers and a magnetic recoil spectrometer implemented in various locations around the NIF target chamber. This provides good implosion coverage and excellent measurement complementarity required for reliable measurements of Y n , T i and ρR, in addition to ρR asymmetries. The data indicate that the implosion performance, characterized by the experimental ignition threshold factor, has improved almost two orders of magnitude since the first shot taken in September 2010. ρR values greater than 1 g cm −2 are readily achieved. Three-dimensional semi-analytical modelling and numerical simulations of the neutron-spectrometry data, as well as other data for the hot spot and main fuel, indicate that a maximum hot-spot pressure of ∼150 Gbar has been obtained, which is almost a factor of two from the conditions required for ignition according to simulations. Observed Y n are also 3–10 times lower than predicted. The conjecture is that the observed pressure and Y n deficits are partly explained by substantial low-mode ρR asymmetries, which may cause inefficient conversion of shell kinetic energy to hot-spot thermal energy at stagnation. (paper)

A Structural Model of Algebra Achievement: Computational Fluency and Spatial Visualisation as Mediators of the Effect of Working Memory on Algebra Achievement

Science.gov (United States)

Tolar, Tammy Daun; Lederberg, Amy R.; Fletcher, Jack M.

2009-01-01

The goal of this study was to develop and evaluate a structural model of the relations among cognitive abilities and arithmetic skills and college students' algebra achievement. The model of algebra achievement was compared to a model of performance on the Scholastic Assessment in Mathematics (SAT-M) to determine whether the pattern of relations…

High-Performance Cryogenic Designs for OMEGA and the National Ignition Facility

Science.gov (United States)

Goncharov, V. N.; Collins, T. J. B.; Marozas, J. A.; Regan, S. P.; Betti, R.; Boehly, T. R.; Campbell, E. M.; Froula, D. H.; Igumenshchev, I. V.; McCrory, R. L.; Myatt, J. F.; Radha, P. B.; Sangster, T. C.; Shvydky, A.

2016-10-01

The main advantage of laser symmetric direct drive (SDD) is a significantly higher coupled drive laser energy to the hot-spot internal energy at stagnation compared to that of laser indirect drive. Because of coupling losses resulting from cross-beam energy transfer (CBET), however, reaching ignition conditions on the NIF with SDD requires designs with excessively large in-flight aspect ratios ( 30). Results of cryogenic implosions performed on OMEGA show that such designs are unstable to short-scale nonuniformity growth during shell implosion. Several CBET reduction strategies have been proposed in the past. This talk will discuss high-performing designs using several CBET-mitigation techniques, including using drive laser beams smaller than the target size and wavelength detuning. Designs that are predicted to reach alpha burning regimes as well as a gain of 10 to 40 at the NIF-scale will be presented. Hydrodynamically scaled OMEGA designs with similar CBET-reduction techniques will also be discussed. This material is based upon work supported by the Department Of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

The Effect of Subconscious Performance Goals on Academic Performance

Science.gov (United States)

Bipp, Tanja; Kleingeld, Ad; van Mierlo, Heleen; Kunde, Wilfried

2017-01-01

We investigated the impact of subconscious goals on academic performance in two field experiments. We show that unobtrusive priming of goals with regard to achievement motivation by means of a photograph improves performance in different educational contexts. High-school students who were exposed to an achievement-related photograph achieved…

Predicting Arithmetical Achievement from Neuro-Psychological Performance: A Longitudinal Study.

Science.gov (United States)

Fayol, Michel; Barrouillet, Pierre; Marinthe, Catherine

1998-01-01

Assessed whether performances of 5- and 6-year olds in arithmetic tests can be predicted from their performances in neuropsychological tests. Participants completed neuropsychological, drawing, and arithmetic tests at 5 and 6 years of age. Findings at older age were correctly assumed by conclusions of first evaluation. (LBT)

Optical performance evaluation of a solar furnace by measuring the highly concentrated solar flux

International Nuclear Information System (INIS)

Lee, Hyunjin; Chai, Kwankyo; Kim, Jongkyu; Lee, Sangnam; Yoon, Hwanki; Yu, Changkyun; Kang, Yongheack

2014-01-01

We evaluated optical performance of a solar furnace in the KIER (Korea Institute of Energy Research) by measuring the highly concentrated solar flux with the flux mapping method. We presented and analyzed optical performance in terms of concentrated solar flux distribution and power distribution. We investigated concentration ratio, stagnation temperature, total power, and concentration accuracy with help of a modeling code based on the ray tracing method and thereby compared with other solar furnaces. We also discussed flux changes by shutter opening angles and by position adjustment of reflector facets. In the course of flux analysis, we provided a better understanding of reference flux measurement for calibration, reflectivity measurement with a portable reflectometer, shadowing area consideration for effective irradiation, as well as accuracy and repeatability of flux measurements. The results in the present study will help proper utilization of a solar furnace by facilitating comparison between flux measurements at different conditions and flux estimation during operation

Reports on research achievements in developing high-performance industrial furnaces in fiscal 1998 (Research and development of high-performance industrial furnaces). Volume 1; 1998 nendo koseino kogyoro nado ni kansuru kenkyu kaihatsu seika hokokusho. 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

From the reports on research achievements in developing high-performance industrial furnaces in fiscal 1998, the report volume 1 was prepared as a research achievement report of each working group, detailing fundamental researches, heating furnaces, and heat treatment furnaces. The fundamental researches have researched combustion evaluating technology, characteristics of the area in the vicinity of a combustor, characteristics of combustion of high-temperature air, heating characteristics of a furnace to investigate effect of local heat absorption, and combustion evaluation. For the heating furnaces, the following subjects were studied: development of an in-furnace combustion model, summary of an experiment for evaluating high-temperature air combustion, furnace height relative to combustion heat transfer characteristics, heat loss minimizing technology, combustion heat transfer characteristics of liquid fuels, optimal operation of the high-temperature air combustion, basic control in heating control, and steel piece heating control. Studies were performed for the heat treatment furnaces on the case of a direct firing furnace in evaluating the heat transfer characteristics, the case of a radiant tube furnace, application of thermal fluid simulation technology, furnace averaging technology, soot reducing technology, control technology, and trial design on a high-performance heat treatment furnace. (NEDO)

TOP PRIORITI QMS PRINCIPLES FOR ACHIEVING BUSINESS EXCELLENCE

Directory of Open Access Journals (Sweden)

Aleksandar Vujović

2010-06-01

Full Text Available The main target of this paper is to select top priority principles of QMS for achieving business excellence. This could be done from the standpoint of significant of principles. That means that. organization should make more attention to this principles in the way for making excellent results. This paper has been developed as a tendency of researchers in the Center for quality-Faculty of mechanical engineering in Podgorica to establish a model for improvement of business processes performances based on quality management system through comparison with top organizational performances characterized by criteria i.e. particularities of the business excellence model. Correlation of principles of the quality management system with QMS principles has been established to that effect. Weight coefficients have been also determined for each principle individually. Thereby key principles were identified, namely priorities in terms of achieving business excellence i.e. areas (principles were given priorities, that is to say principles that play the biggest part in achieving business excellence.

Student Perceptions of High-Achieving Classmates

Science.gov (United States)

Händel, Marion; Vialle, Wilma; Ziegler, Albert

2013-01-01

The reported study investigated students' perceptions of their high-performing classmates in terms of intelligence, social skills, and conscientiousness in different school subjects. The school subjects for study were examined with regard to cognitive, physical, and gender-specific issues. The results show that high academic achievements in…

Achieving transparency in the total system performance assessment of a potential high level radioactive waste repository at Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Bailey, J.; Rickertsen, L.; Cotton, T.

1999-01-01

This paper has presented an approach to quantitative assessment of the degree of postclosure defense-in-depth provided by the reference system of the VA (Viability Assessment). This approach identifies principal barriers, assesses barriers for common uncertainty and failure mode, conducts barrier neutralization analyses, and evaluates overall defense-in-depth. The neutralization approach of step 3 is particularly useful in untangling the contributions of various barriers to the results calculated by performance assessments. In fact, it provides the only way of assessing the contribution of barriers that are fully redundant with one another. The approach has been applied to the VA reference system. It shows how the natural transport barriers contribute to performance of the system. Since their individual contributions are redundant, uncertainties in those individual contributions are reduced in importance. The analyses also suggest uncertainties common to both of these barriers are important to the safety assessment. Thus, the approach appears to be capable of determining the contribution of the principal barriers to system performance. The ability to use performance assessment to show not only how the repository system is expected to perform, but also how it achieves that performance, should contribute substantially towards providing needed transparency to the safety case for a geologic repository. It is also a valuable tool during the development of the repository design and associated safety case, by identifying areas in which performance would be enhanced by increased redundancy

Relationship between attainment of recommended physical activity guidelines and academic achievement: undergraduate students in Egypt.

Science.gov (United States)

El Ansari, Walid; Stock, Christiane

2014-07-14

We assessed and compared by gender, students' achievement of recommended guidelines of four PA forms, and the association between guideline achievement of each of the four PA forms and students' academic performance. Data (2009-2010) comprised 3,271 students (11 faculties) at Assiut University, Egypt. A self-administered questionnaire measured: moderate PA (MPA), vigorous PA (VPA), moderate to vigorous PA (MVPA), muscle-strengthening PA; five socio-demographic variables (gender, age, year of study, father's education, living arrangements during semester); self-rated health; and, academic performance. We compared the levels of four PA forms, socio-demographic variables, and academic performance by gender. Binary logistic regression examined the factors associated with achieving the guidelines of the four PA forms. Linear regression examined the association between frequency of four PA forms and level of academic performance. Nearly equal proportions of males and females (37%, 36%) achieved the MPA guidelines. Significantly more males achieved the VPA, MVPA, and muscle strengthening PA guidelines. Father's education was positively associated with achieving all four PA guidelines (with each increasing educational achievement of the father, student's odds of achieving PA guidelines increased by 7-9%). Students living with their parents or room mates off campus were more likely to achieve the VPA and MVPA guidelines. Students who achieved VPA and MVPA guidelines were more likely to report better academic performance. For all PA forms (except MPA), increasing academic achievement was positively associated with increasing frequency of PA, but standardised Beta (0.05-0.07) suggested a modest correlation between academic achievement and PA frequency. The linear association between frequency of PA and academic achievement, and the finding that the proportions of students who achieved the recommended levels of several forms of PA were below half of the sample call for higher

Straight cylindrical seal for high-performance turbomachines

Science.gov (United States)

Hendricks, Robert C.

1987-01-01

A straight cylindrical seal configuration representing the seal for a high-performance turbopump (e.g., the space shuttle main engine fuel pump) was tested under static (nonrotating) conditions. The test data included critical mass flux and pressure profiles over a wide range of inlet temperatures and pressures for fluid nitrogen and fluid hydrogen with the seal in concentric and fully eccentric positions. The critical mass fluxes (or leakage rates) for the concentric and fully eccentric configurations were nearly the same when based on stagnation conditions upstream of the seal. The fully eccentric configuration pressure profiles of the gas and liquid were different. Further, the pressure differences between the maximum and the minimum clearance positions were highly dependent on the geometric conditions, the temperature, and the absolute pressure at both the inlet and the exit. The pressure differences were greatest in the inlet region. The results, although complex, tend to follow the corresponding-states principles for critical flows. Gaseous injection near the seal exit plane significantly altered the pressure profiles and could be used to control turbomachine instabilities.

Student Achievement in Ohio Charter Schools: A Comparative and Longitudinal Study

Science.gov (United States)

Kotler, Ruth M.

2012-01-01

The purpose of this study was to investigate fifth-grade student achievement in Ohio public charter schools as compared to student achievement in traditional public schools, and to determine whether the performance of charter schools changed over time. Research questions asked 1) how does student achievement in Ohio's public charters compare to…

Dutch corporatism: Does it still work? Policy formation and macroeconomic performance 1980-2005

NARCIS (Netherlands)

Woldendorp, J.J.; Delsen, L.

2008-01-01

This paper challenges the analysis of Dutch corporatism as evolving from a model of institutional sclerosis and political stagnation in the 1980s that transformed the Dutch Disease by means of the so-called Polder Model into the Dutch Miracle in the late 1990s. Two questions are addressed in this

Influence Model Assisted Learning Cycle Mind Map to Achievement Physics Laboratory Judging from the performance Grade VIII SMPN 1 Rejoso Pasuruan

OpenAIRE

Ary Analisa Rahma

2014-01-01

Pengaruh Model Siklus Belajar Berbantuan Mind Map terhadap Prestasi Belajar Fisika Ditinjau dari Kinerja Laboratorium Siswa Kelas VIII SMPN 1 Rejoso Kabupaten Pasuruan Abstract: This study aimed to examine the effect of the learning cycle models aided the mind map on the learning achievement in terms of the performance of laboratory physics class VIII student on light material in SMP Negeri 1 Rejoso Pasuruan. This study is a quasi-experimental research. The research design used is a 2 x 2...

Capacity-achieving CPM schemes

OpenAIRE

Perotti, Alberto; Tarable, Alberto; Benedetto, Sergio; Montorsi, Guido

2008-01-01

The pragmatic approach to coded continuous-phase modulation (CPM) is proposed as a capacity-achieving low-complexity alternative to the serially-concatenated CPM (SC-CPM) coding scheme. In this paper, we first perform a selection of the best spectrally-efficient CPM modulations to be embedded into SC-CPM schemes. Then, we consider the pragmatic capacity (a.k.a. BICM capacity) of CPM modulations and optimize it through a careful design of the mapping between input bits and CPM waveforms. The s...

Student Achievement Goal Setting: Using Data to Improve Teaching and Learning

Science.gov (United States)

Stronge, James H.; Grant, Leslie W.

2009-01-01

The first book in the James H. Stronge Research-to-Practice series focuses on improving student achievement through academic goal setting. It offers the tools and plan of action to use performance data to improve instructional practice and increase student achievement. The book is divided into three parts: (1) How Student Achievement Data Can Be…

Why Do Boys and Girls Perform Differently on PISA Reading in Finland? The Effects of Reading Fluency, Achievement Behaviour, Leisure Reading and Homework Activity

Science.gov (United States)

Torppa, Minna; Eklund, Kenneth; Sulkunen, Sari; Niemi, Pekka; Ahonen, Timo

2018-01-01

The present study examined gender gap in Program for International Student Assessment (PISA) Reading and mediators of the gender gap in a Finnish sample (n = 1,309). We examined whether the gender gap in PISA Reading performance can be understood via the effects of reading fluency, achievement behaviour (mastery orientation and task-avoidant…

DETERMINATION OF QMS PRINCIPLE COEFFICIENTS OF SIGNIFICANCE IN ACHIEVING BUSINESS EXCELLENCE

Directory of Open Access Journals (Sweden)

Aleksandar Vujovic

2008-03-01

Full Text Available This paper has been developed as a tendency of researchers in the Center for quality-Faculty of mechanical engineering in Podgorica to establish a model for improvement of business processes performances based on quality management system through comparison with top organizational performances characterized by criteria i.e. particularities of the business excellence model. Correlation of principles of the quality management system with QMS principles has been established to that effect. Weight coefficients have been also determined for each principle individually. Thereby key principles were identified, namely priorities in terms of achieving business excellence i.e. areas (principles were given priorities, that is to say principles that play the biggest part in achieving business excellence. In that way, pre conditions were made to define preventive measures of a certain intensity depending on the weight coefficients, with a goal to improve performances of a certified and process-modulated quality management system in direction of achieving top organizational performances.

Military Deployment and Elementary Student Achievement

Science.gov (United States)

Phelps, Terri; Dunham, Mardis; Lyons, Robert

2010-01-01

This study investigated the impact that military deployment has upon academic achievement of elementary school students. TerraNova test scores of 137 fourth and fifth grade students in two elementary schools with a high proportion of military dependent children were examined for two consecutive years. Although the academic test performance fell…

Student Achievement in Title I Schools

Science.gov (United States)

Diaz, Abby T.

2017-01-01

This researcher seeks to answer the following question: How did two elementary Title I schools, identified as "high performing" on the first Smarter Balanced assessment, address elements of Maslow's hierarchy of needs when developing school-wide initiatives to enhance student achievement? Many students in Title I schools face barriers to…

Factors associated with failure to achieve remission and with relapse after remission in patients with major depressive disorder in the PERFORM study.

Science.gov (United States)

Saragoussi, Delphine; Touya, Maëlys; Haro, Josep Maria; Jönsson, Bengt; Knapp, Martin; Botrel, Bastien; Florea, Ioana; Loft, Henrik; Rive, Benoît

2017-01-01

The Prospective Epidemiological Research on Functioning Outcomes Related to Major Depressive Disorder (PERFORM) study has been initiated to better understand the course of a depressive episode and its impact on patient functioning. This analysis aimed to identify sociodemographic and clinical factors associated with failure to achieve remission at month 2 after initiating or switching antidepressant monotherapy and with subsequent relapse at month 6 for patients in remission at month 2. This was a 2-year observational cohort study in 1,159 outpatients aged 18-65 years with major depressive disorder initiating or undergoing the first switch of antidepressant monotherapy. Factors with P 8 weeks (OR 0.51), being in psychotherapy (OR 0.51), sexual dysfunction (OR 0.62), and severity of depression (OR 0.87). Factors significantly associated with relapse at month 6 were male sex (OR 2.47), being married or living as a couple (OR 2.73), residual patient-reported cognitive symptoms at 2 months (OR 1.12 per additional unit of Perceived Deficit Questionnaire-5 score) and residual depressive symptoms at 2 months (OR 1.27 per additional unit of Patient Health Questionnaire-9 score). Different factors appear to be associated with failure to achieve remission in patients with major depressive disorder and with subsequent relapse in patients who do achieve remission. Patient-reported cognitive dysfunction is an easily measurable and treatable characteristic that may be associated with an increased likelihood of relapse at 6 months in patients who have achieved remission.

Cost/Performance Ratio Achieved by Using a Commodity-Based Cluster

Science.gov (United States)

Lopez, Isaac

2001-01-01

Researchers at the NASA Glenn Research Center acquired a commodity cluster based on Intel Corporation processors to compare its performance with a traditional UNIX cluster in the execution of aeropropulsion applications. Since the cost differential of the clusters was significant, a cost/performance ratio was calculated. After executing a propulsion application on both clusters, the researchers demonstrated a 9.4 cost/performance ratio in favor of the Intel-based cluster. These researchers utilize the Aeroshark cluster as one of the primary testbeds for developing NPSS parallel application codes and system software. The Aero-shark cluster provides 64 Intel Pentium II 400-MHz processors, housed in 32 nodes. Recently, APNASA - a code developed by a Government/industry team for the design and analysis of turbomachinery systems was used for a simulation on Glenn's Aeroshark cluster.

Glioma Surgery: Technological Advances to Achieve a Maximal Safe Resection.

Science.gov (United States)

Altieri, Roberto; Zenga, Francesco; Fontanella, Marco Maria; Cofano, Fabio; Agnoletti, Alessandro; Spena, Giannantonio; Crobeddu, Emanuela; Fornaro, Riccardo; Ducati, Alessandro; Garbossa, Diego

2015-11-01

Glioblastoma multiforme (GBM) is the most frequent primary central nervous system (CNS) tumor. Despite the best treatment and advances in therapy, prognosis remains poor. One of the mainstays of therapy in GBM is surgical excision. Several studies have confirmed that the extent of resection (EOR) positively influences overall survival (OS) in patients with high-grade gliomas (HGGs). A literature search was performed using PubMed to assess the useful neurosurgical tools to achieve the best neurosurgical performance. In order to achieve the major extent of resection, preserving neurological function, many tools are now available, especially neuronavigation, intraoperative fluorescence, intraoperative ultrasound, and neuromonitoring. In addition to the maximal excision of tumor, the neurosurgeon can use photodynamic therapy (PTD) and local drug delivery (LDD) to improve the local control and bridge conventional radio and chemotherapy. EOR improves OS in patients with HGGs. There are technological possibilities for achieving a complete resection preserving neurological function, and it is not acceptable to perform only biopsy of these lesions.

The Impact of Achievement Goals on Cardiorespiratory Fitness: Does Self-Efficacy Make a Difference?

Science.gov (United States)

Gao, Zan; Xiang, Ping; Lochbaum, Marc; Guan, Jianmin

2013-01-01

Purpose: The relationships among students' self-efficacy, 2 × 2 achievement goals (mastery-approach [MAp], mastery-avoidance [MAv], performance-approach [PAp], and performance-avoidance goals), and achievement performance remain largely unanswered. We tested a model of the mediating role of self-efficacy on the relationship between 2 × 2…

Nonlinear radiative heat transfer in magnetohydrodynamic (MHD stagnation point flow of nanofluid past a stretching sheet with convective boundary condition

Directory of Open Access Journals (Sweden)

Wubshet Ibrahim

2015-12-01

Full Text Available Two-dimensional boundary layer flow of nanofluid fluid past a stretching sheet is examined. The paper reveals the effect of non-linear radiative heat transfer on magnetohydrodynamic (MHD stagnation point flow past a stretching sheet with convective heating. Condition of zero normal flux of nanoparticles at the wall for the stretched flow is considered. The nanoparticle fractions on the boundary are considered to be passively controlled. The solution for the velocity, temperature and nanoparticle concentration depends on parameters viz. Prandtl number Pr, velocity ratio parameter A, magnetic parameter M, Lewis number Le, Brownian motion Nb, and the thermophoresis parameter Nt. Moreover, the problem is governed by temperature ratio parameter (Nr=TfT∞ and radiation parameter Rd. Similarity transformation is used to reduce the governing non-linear boundary-value problems into coupled higher order non-linear ordinary differential equation. These equations were numerically solved using the function bvp4c from the matlab software for different values of governing parameters. Numerical results are obtained for velocity, temperature and concentration, as well as the skin friction coefficient and local Nusselt number. The results indicate that the skin friction coefficient Cf increases as the values of magnetic parameter M increase and decreases as the values of velocity ratio parameter A increase. The local Nusselt number −θ′(0 decreases as the values of thermophoresis parameter Nt and radiation parameter Nr increase and it increases as the values of both Biot number Bi and Prandtl number Pr increase. Furthermore, radiation has a positive effect on temperature and concentration profiles.

STUDENTS’ SELF-ASSESSMENT OF ONE’S ABILITIES FOR THEIR LIFE GOALS ACHIEVEMENT

Directory of Open Access Journals (Sweden)

Stanislava Stoyanova

2017-12-01

Full Text Available Goal achievement is considered to be related to need satisfaction, motivation, and self-esteem. The self-assessed abilities for goal achievement were operationalized as positive self-talk, perceived self-efficacy, the performance level of doing a task, the aspiration level, the in/congruence between performance and prognosis, and frustration tolerance to pursue one’s goals in spite of some obstacles. In total, 392 students whose mean age was 21 years old were investigated, divided in sub-samples, with the positive self-talk scale from the ASTQS questionnaire, the self-efficacy scale by Schwarzer & Jerusalem, and the AHA computerized test method from Vienna test system. Students’ self-assessment of one’s abilities for goal achievement revealed the most frequent high levels of perceived self-efficacy and good performance in coding tasks. The other self-assessed abilities for goal achievement were expressed more often at a medium level. The gender differences in the performance level of doing a task were compared to some previous results that indicated a variety of trends, because of the age peculiarities and the types of the tasks that were executed. The advance in age was related to more frequent use of positive self-talk and lower aspiration level, besides to lower performance level. The proposed model of the abilities for goal achievement was successfully approbated in this study revealing the strengths in the students’ self-assessment of one’s abilities for goal achievement and some weaknesses that should be the focus of further interventions in order to increase the students’ frustration tolerance ability and the use of positive self-talk.

Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

Science.gov (United States)

Barton Richard J.

2012-01-01

current generation tags limits the performance in a cluttered sensing environment. That is, as more SAW-based sensors are added to the environment, numerous tag responses are superimposed at the receiver and decoding all or even a subset of the telemetry becomes increasingly difficult. Background clutter generated by reflectors other than the sensors themselves is also a problem, as is multipath interference and signal distortion, but the limiting factor in many remote sensing applications can be expected to be tag mutual interference. This problem may be greatly mitigated by proper design of the SAW tag waveform, but that remains an open research problem, and in the meantime, several other related questions remain to be answered including: (1) What are the fundamental relationships between tag parameters such as bit-rate, time-bandwidth-product, SNR, and achievable collision resolution? (2) What are the differences in optimal or near-optimal interrogator designs between noise-limited environments and interference-limited environments? (3) What are the performance characteristics of different interrogator designs in term of parameters such as transmitter power level, range, and number of interfering tags? In this paper, we will present the results of a research effort aimed at providing at least partial answers to all of these questions.

Student Perceptions of Classroom Achievement Goals as Predictors of Belonging and Content Instrumentality

Science.gov (United States)

Walker, Christopher O.

2012-01-01

The goal of the current study was to examine the predictive relationships among a set of cognitive-motivational variables that have been found in previous studies to support academic achievement. Student perception of a classroom's achievement goal structure (classroom mastery, classroom performance-approach, classroom performance-avoidance) was…

A Proposed Model for Assessing Organisational Culture Towards Achieving Business Objectives

Directory of Open Access Journals (Sweden)

Hafez Salleh

2011-09-01

Full Text Available Most of the traditional business performances measures are based on productivity and process criteria, which mainly focus on method of investment appraisal such as payback method, return on investment (ROI, cost-benefits analysis (CBA, net present value (NPV, internal rate of return (IRR. However, the measurement scales of business performance are not limited to those measures. One element that has strong correlation to the business performances is ‘organisational culture’. Many studies proved that one of the significant criteria for achieving desired business objectives is the right organisational culture within workplace. Basically, the measurement of organisational culture is reflecting on two distinct elements: organisational culture and business objectives. In broader perspective, an organisation is considered effective if it meets its business objectives. This paper aims to present and discuss the preliminary culture model to indicate the culture performance within organisational. The model has been developed through literature review, expert opinion and experience which is anticipated of being able to potentially measure the culture capability of organisations across industries to “successfully achieve business objectives”. The model is composed of six progressive stages of maturity that an organisation can achieve its culture performance. For each maturity stage, the model describes a set of characteristics that must be in place for the company to achieve each stage. The validity of the proposed model will be tested by a few case studies. The idea is to provide managers with a qualitative measurement tools to enable them to identify where culture improvements are required within their organisations and to indicate their readiness for achieving business objectives.

How to Change 5000 Schools: A Practical and Positive Approach for Leading Change at Every Level

Science.gov (United States)

Levin, Ben

2008-01-01

Not long ago, public education in Ontario, Canada, was in deep trouble. Student achievement was stagnating, labor disruptions were rampant, and public satisfaction with the schools was low. In 2003, a new provincial government initiated a series of reforms that embodied a positive, outcome-focused agenda for public education. Today, student…

Ethnic differences in adolescent achievement. An ecological perspective.

Science.gov (United States)

Steinberg, L; Dornbusch, S M; Brown, B B

1992-06-01

Using data collected from a large sample of high school students, the authors challenge three widely held explanations for the superior school performance of Asian-American adolescents, and the inferior performance of African- and Hispanic-American adolescents: group differences in (a) parenting practices, (b) familial values about education, and (c) youngsters' beliefs about the occupational rewards of academic success. They found that White youngsters benefit from the combination of authoritative parenting and peer support for achievement, whereas Hispanic youngsters suffer from a combination of parental authoritarianism and low peer support. Among Asian-American students, peer support for academic excellence offsets the negative consequences of authoritarian parenting. Among African-American youngsters, the absence of peer support for achievement undermines the positive influence of authoritative parenting.

Second-year medical students' motivational beliefs, emotions, and achievement.

Science.gov (United States)

Artino, Anthony R; La Rochelle, Jeffery S; Durning, Steven J

2010-12-01

A challenge for medical educators is to better understand the personal factors that lead to individual success in medical school and beyond. Recently, educational researchers in fields outside medicine have acknowledged the importance of motivation and emotion in students' learning and performance. These affective factors have received less emphasis in the medical education literature. This longitudinal study examined the relations between medical students' motivational beliefs (task value and self-efficacy), achievement emotions (enjoyment, anxiety and boredom) and academic achievement. Second-year medical students (n=136) completed motivational beliefs and achievement emotions surveys following their first and second trimesters, respectively. Academic achievement was operationalised as students' average course examination grades and national board shelf examination scores. The results largely confirmed the hypothesised relations between beliefs, emotions and achievement. Structural equation modelling revealed that task value beliefs were positively associated with course-related enjoyment (standardised regression coefficient [β] = 0.59) and were negatively related to boredom (β= -0.25), whereas self-efficacy beliefs were negatively associated with course-related anxiety only (β = -0.47). Furthermore, student enjoyment was positively associated with national board shelf examination score (β = 0.31), whereas anxiety and boredom were both negatively related to course examination grade (β= -0.36 and -0.27, respectively). The overall structural model accounted for considerable variance in each of the achievement outcomes: R(2) = 0.20 and 0.14 for the course examination grade and national board shelf examination score, respectively. This study suggests that medical students' motivational beliefs and achievement emotions are important contributors to their academic achievement. These results have implications for medical educators striving to understand the

Parenting styles and adolescents' achievement strategies.

Science.gov (United States)

Aunola, K; Stattin, H; Nurmi, J E

2000-04-01

The aim of the study was to investigate the extent to which adolescents' achievement strategies are associated with the parenting styles they experience in their families. Three hundred and fifty-four 14-year-old adolescents completed a Strategy and Attribution Questionnaire and a family parenting style inventory. Analogous questionnaires were also completed by the adolescents' parents. Based on adolescents' report of the parenting styles, four types of families were identified: those with Authoritative, Authoritarian, Permissive, and Neglectful parenting styles. The results further showed that adolescents from authoritative families applied most adaptive achievement strategies characterized by low levels of failure expectations, task-irrelevant behaviour and passivity, and the use of self-enhancing attributions. Adolescents from neglectful families, in turn, applied maladaptive strategies characterized by high levels of task-irrelevant behaviour, passivity and a lack of self-enhancing attributions. The results provide a basis for understanding some of the processes by which parenting styles may influence adolescents' academic achievement and performance.

Achieving Transformational Materials Performance in a New Era of Science

International Nuclear Information System (INIS)

Sarrao, John

2009-01-01

The inability of current materials to meet performance requirements is a key stumbling block for addressing grand challenges in energy and national security. Fortunately, materials research is on the brink of a new era - a transition from observation and validation of materials properties to prediction and control of materials performance. In this talk, I describe the nature of the current challenge, the prospects for success, and a specific facility concept, MaRIE, that will provide the needed capabilities to meet these challenges, especially for materials in extreme environments. MaRIE, for Matter-Radiation Interactions in Extremes, is Los Alamos' concept to realize this vision of 21st century materials research. This vision will be realized through enhancements to the current LANSCE accelerator, development of a fourth-generation x-ray light source co-located with the proton accelerator, and a comprehensive synthesis and characterization facility focused on controlling complex materials and the defect/structure link to materials performance.

Undergraduate Academic Achievement as an Indicator of Fleet Performance and Retention

National Research Council Canada - National Science Library

Gremillion, John

1998-01-01

...) and retention in the Navy. Understanding the relationship between college academic performance and job performance is important because of the organizational and cultural emphasis placed on academic grades...

Cryogenics system: strategy to achieve nominal performance and reliable operation

CERN Document Server

Bremer, J; Casas, J; Claudet, S; Delikaris, D; Delruelle, N; Ferlin, G; Fluder, C; Perin, A; Perinic, G; Pezzetti, M; Pirotte, O; Tavian, L; Wagner, U

2012-01-01

During the LHC operation in 2010 and 2011, the cryogenic system has achieved an availability level fulfilling the overall requirement. To reach this level, the cryogenic system has profited like many other beam-dependent systems from the reduced beam parameters. Therefore, impacts of some failures occurred during the LHC operation were mitigated by using the overcapacity margin, the existing built-in redundancy in between adjacent sector cryogenic plants and the "cannibalization" of spares on two idle cryogenic plants. These two first years of operation were also crucial to identify the weaknesses of the present cryogenic maintenance plan and new issues like SEUs. After the LS1, nominal beam parameters are expected and the mitigated measures will be less effective or not applicable at all. Consequently, a consolidation plan to improve the MTBF and the MTTR of the LHC cryogenic system is under definition. Concerning shutdown periods, the present cryogenic sectorization imposes some restrictions in the type of ...

The Classroom Performance System (CPS): Effects on student participation, attendance, and achievement in multicultural anatomy and physiology classes at South Texas College

Science.gov (United States)

Termos, Mohamad Hani

2011-12-01

The Classroom Performance System (CPS) is an instructional technology tool that increases student performance and addresses different learning styles. Instructional technologies are used to promote active learning; however, student embarrassment issue in a multicultural setting is not addressed. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes at South Texas College, where the first spoken language is not English. Quantitative method and quasi-experimental design were employed and comparative statistic methods and pre-post tests were used to collect the data. Participants were college students and sections of study were selected by convenient sampling. Participation was 100% during most of the lectures held and participation rate did not strike above 68% in control group. Attendance was significantly higher in CPS sections than the control group as shown by t-tests. Experimental sections had a higher increase in the pre-post test scores and student averages on lecture exams increased at a higher rate as compared to the control group. Therefore, the CPS increased student participation, attendance, and achievement in multicultural anatomy and physiology classes. The CPS can be studied in other settings where the first spoken language is English or in other programs, such as special education programs. Additionally, other variables can be studied and other methodologies can be employed.

Gender-Based Differential Item Performance in Mathematics Achievement Items.

Science.gov (United States)

Doolittle, Allen E.; Cleary, T. Anne

1987-01-01

Eight randomly equivalent samples of high school seniors were each given a unique form of the ACT Assessment Mathematics Usage Test (ACTM). Signed measures of differential item performance (DIP) were obtained for each item in the eight ACTM forms. DIP estimates were analyzed and a significant item category effect was found. (Author/LMO)

Self-Esteem, Achievement Goals, and Self-Handicapping in College Physical Education.

Science.gov (United States)

Chen, Zuosong; Sun, Kaihong; Wang, Kun

2017-01-01

This study aims to investigate the relationships among self-esteem, achievement goals, and self-handicapping and the potential mediating role of achievement goals in the relationship between self-esteem and self-handicapping in college physical education. The participants were 320 Chinese college students. Three validated scales were employed to assess participants' self-esteem, achievement goals, and self-handicapping in college physical education. Results showed that self-esteem had a negative effect on self-handicapping. Self-esteem had a positive effect on mastery goals, but had a negative effect on performance-avoidance goals. Mastery goals had a negative effect and performance-avoidance goals had a positive effect on self-handicapping. Moreover, mastery goals and performance-avoidance goals partially mediated the relationship between self-esteem and self-handicapping, and self-esteem had both direct and indirect effects on self-handicapping in college physical education. The findings indicate that improving individual's self-esteem and promoting mastery goals while reducing performance-avoidance goals may be relevant strategies to reduce self-handicapping in college physical education.

Determination of Performance Measuring Parameters of an Improved Dual Paraboloid Solar Cooker

Directory of Open Access Journals (Sweden)

Suhail Zaki Farooqui

2017-01-01

Full Text Available An experimental investigation into the performance evaluation of an improved dual reflector foldable paraboloid solar cooker has been reported, along with its energy and exergy analysis. The best attribute of this lightweight and low-cost solar cooker is its high performance coupled with the ease of handling. The cooker utilizes two paraboloid reflectors made out of Mylar-coated fiberglass dishes, each having a diameter of 90 cm and focal length of 105 cm. The total intercepted radiation energy is 1.08 kW under standard test conditions. Stagnation temperatures of up to 330°C and cooking temperatures of up to 290°C have been attained with load. Altogether, 9 experiments have been performed with and without load. Loaded tests have been conducted with water and vegetable oil. Results indicate an average cooking power of 485 W, peak exergy gain of 60.53 W, quality factor of 0.077, and a high product of temperature difference gap at half peak power to peak power of 4364.33 W·K. The maximum exergy output power attained was 70 W, while maximum exergy efficiency was 8–10%. All performance measuring parameters indicate that it is a high performance solar cooker for rural and urban communities and is suitable for all types of oil- and water-based cooking.

Millennium development goals: Examining Kenya constraints in achieving the eight goals

Directory of Open Access Journals (Sweden)

Wambua Leonard Munyao

2013-06-01

Full Text Available This paper examines Kenya’s performance in achieving the famous millennium development goals. The paper provides the government and other stakeholders with proper understanding of the constraints of achieving the millennium development goals as well as reflecting the phase and the passion of the country in achieving this important development goal. The paper further seeks to stress the importance of this goal in reducing poverty in the country. The paper has cited some key factors undermining achieving of the millennium development goals in Kenya. Major recommendations that can contribute towards achieving of the millennium development goals have also been made.

Achieving single channel, full duplex wireless communication

KAUST Repository

Choi, Jung Il; Jain, Mayank; Srinivasan, Kannan; Levis, Phil; Katti, Sachin

2010-01-01

This paper discusses the design of a single channel full-duplex wireless transceiver. The design uses a combination of RF and baseband techniques to achieve full-duplexing with minimal effect on link reliability. Experiments on real nodes show the full-duplex prototype achieves median performance that is within 8% of an ideal full-duplexing system. This paper presents Antenna Cancellation, a novel technique for self-interference cancellation. In conjunction with existing RF interference cancellation and digital baseband interference cancellation, antenna cancellation achieves the amount of self-interference cancellation required for full-duplex operation. The paper also discusses potential MAC and network gains with full-duplexing. It suggests ways in which a full-duplex system can solve some important problems with existing wireless systems including hidden terminals, loss of throughput due to congestion, and large end-to-end delays. Copyright 2010 ACM.

Influences of Deqi on Immediate Analgesia Effect of Needling SP6 (Sanyinjiao in Patients with Primary Dysmenorrhea in Cold and Dampness Stagnation Pattern: Study Protocol for a Randomized Controlled Trial

Directory of Open Access Journals (Sweden)

Yu-qi Liu

2015-01-01

Full Text Available Deqi, according to traditional Chinese medicine, is a specific needle sensation during the retention of needles at certain acupoints and is considered to be necessary to produce therapeutic effects from acupuncture. Although some modern researches have showed that Deqi is essential for producing acupuncture analgesia and anesthesia, the data are not enough. It is a paper of a multicenter, randomized controlled study protocol, to evaluate the influences of Deqi on acupuncture SP6 in Cold and Dampness Stagnation pattern primary dysmenorrhea patients, in terms of reducing pain and anxiety, and to find out the relationship between Deqi and the temperature changes at SP6 (Sanyinjiao and CV4 (Guanyuan. The results of this trial will be helpful to explain the role of Deqi in acupuncture analgesia and may provide a new objective index for measuring Deqi in the future study. This trial is registered with ChiCTR-TRC-13003086.

Goal Orientations of General Chemistry Students via the Achievement Goal Framework

Science.gov (United States)

Lewis, Scott E.

2018-01-01

The Achievement Goal Framework describes students' goal orientations as: task-based, focusing on the successful completion of the task; self-based, evaluating performance relative to one's own past performance; or other-based, evaluating performance relative to the performance of others. Goal orientations have been used to explain student success…

[Perceptions of classroom goal structures, personal achievement goal orientations, and learning strategies].

Science.gov (United States)

Miki, Kaori; Yamauchi, Hirotsugu

2005-08-01

We examined the relations among students' perceptions of classroom goal structures (mastery and performance goal structures), students' achievement goal orientations (mastery, performance, and work-avoidance goals), and learning strategies (deep processing, surface processing and self-handicapping strategies). Participants were 323 5th and 6th grade students in elementary schools. The results from structural equation modeling indicated that perceptions of classroom mastery goal structures were associated with students' mastery goal orientations, which were in turn related positively to the deep processing strategies and academic achievement. Perceptions of classroom performance goal stractures proved associated with work avoidance-goal orientations, which were positively related to the surface processing and self-handicapping strategies. Two types of goal structures had a positive relation with students' performance goal orientations, which had significant positive effects on academic achievement. The results of this study suggest that elementary school students' perceptions of mastery goal structures are related to adaptive patterns of learning more than perceptions of performance goal structures are. The role of perceptions of classroom goal structure in promoting students' goal orientations and learning strategies is discussed.

Performance Achievement As The Impact Of Strategy Organizatonal Competence Strategy Execution And Competitive Advantage A Study On Private Polytechnics In West Java Indonesia

Directory of Open Access Journals (Sweden)

Bertha Musty

2015-08-01

Full Text Available ABSTRACT - The higher education environment has changed faster than the ability of higher education to respond the competition becomes more intense complex and dynamic making some polytechnics can thrive survive and others are stopping operations. This study was conducted to examine the profile of 29 polytechnics in West Java to achieve organizational performance. Research results show that polytechnic performance is affected by the quality of the execution and its competitive advantage which are determined by the precision and alignment strategies with organizational competence. The model findings of this study could be an analysis tool to solve the polytechnics survival problems how to face the intense competition and changing environment.

Design optimization studies for nonimaging concentrating solar collector tubes

Science.gov (United States)

Winston, R.; Ogallagher, J. J.

1983-09-01

The Integrated Stationary Evacuated Concentrator or ISEC solar collector panel which achieved the best high temperature performance ever measured with a stationary collector was examined. A development effort review and optimize the initial proof of concept design was completed. Changes in the optical design to improve the angular response function and increase the optical efficiency were determined. A recommended profile design with a concentration ratio of 1.55x and an acceptance angle of + - 35(0) was identified. Two alternative panel/module configurations are recommended based on the preferred double ended flow through design. Parasitic thermal and pumping losses show to be reducible to acceptable levels, and two passive approaches to the problem of ensuring stagnation survival are identified.

Measuring more than we know? An examination of the motivational and situational influences in science achievement

Science.gov (United States)

Haydel, Angela Michelle

The purpose of this dissertation was to advance theoretical understanding about fit between the personal resources of individuals and the characteristics of science achievement tasks. Testing continues to be pervasive in schools, yet we know little about how students perceive tests and what they think and feel while they are actually working on test items. This study focused on both the personal (cognitive and motivational) and situational factors that may contribute to individual differences in achievement-related outcomes. 387 eighth grade students first completed a survey including measures of science achievement goals, capability beliefs, efficacy related to multiple-choice items and performance assessments, validity beliefs about multiple-choice items and performance assessments, and other perceptions of these item formats. Students then completed science achievement tests including multiple-choice items and two performance assessments. A sample of students was asked to verbalize both thoughts and feelings as they worked through the test items. These think-alouds were transcribed and coded for evidence of cognitive, metacognitive and motivational engagement. Following each test, all students completed measures of effort, mood, energy level and strategy use during testing. Students reported that performance assessments were more challenging, authentic, interesting and valid than multiple-choice tests. They also believed that comparisons between students were easier using multiple-choice items. Overall, students tried harder, felt better, had higher levels of energy and used more strategies while working on performance assessments. Findings suggested that performance assessments might be more congruent with a mastery achievement goal orientation, while multiple-choice tests might be more congruent with a performance achievement goal orientation. A variable-centered analytic approach including regression analyses provided information about how students, on

Flow Structure and Heat Transfer of Jet Impingement on a Rib-Roughened Flat Plate

Directory of Open Access Journals (Sweden)

Abdulrahman H. Alenezi

2018-06-01

Full Text Available The jet impingement technique is an effective method to achieve a high heat transfer rate and is widely used in industry. Enhancing the heat transfer rate even minimally will improve the performance of many engineering systems and applications. In this numerical study, the convective heat transfer process between orthogonal air jet impingement on a smooth, horizontal surface and a roughened uniformly heated flat plate is studied. The roughness element takes the form of a circular rib of square cross-section positioned at different radii around the stagnation point. At each location, the effect of the roughness element on heat transfer rate was simulated for six different heights and the optimum rib location and rib dimension determined. The average Nusselt number has been evaluated within and beyond the stagnation region to better quantify the heat transfer advantages of ribbed surfaces over smooth surfaces. The results showed both flow and heat transfer features vary significantly with rib dimension and location on the heated surface. This variation in the streamwise direction included both augmentation and decrease in heat transfer rate when compared to the baseline no-rib case. The enhancement in normalized averaged Nusselt number obtained by placing the rib at the most optimum radial location R/D = 2 was 15.6% compared to the baseline case. It was also found that the maximum average Nusselt number for each location was achieved when the rib height was close to the corresponding boundary layer thickness of the smooth surface at the same rib position.

Characteristics of self-worth protection in achievement behaviour.

Science.gov (United States)

Thompson, T

1993-11-01

Two experiments are reported comprising an investigation of individual difference variables associated with self-worth protection. This is a phenomenon whereby students in achievement situations adopt one of a number of strategies, including withdrawing effort, in order to avoid damage to self-esteem which results from attributing failure to inability. Experiment 1 confirmed the adequacy of an operational definition which identified self-worth students on the basis of two criteria. These were deteriorated performance following failure, together with subsequent enhanced performance following a face-saving excuse allowing students to explain failure without implicating low ability. The results of Experiment 2 established that the behaviour of self-worth protective students in achievement situations may be understood in terms of their low academic self-esteem coupled with uncertainty about their level of global self-esteem. Investigation of the manner in which self-worth students explain success and failure outcomes failed to demonstrate a tendency to internalise failure but revealed a propensity on the part of these students to reject due credit for their successes. The implications of these findings in terms of the prevention and modification of self-worth protective reactions in achievement situations are discussed.

Relationship between Achievement Goals and Students' Self-Reported Personal and Social Responsibility Behaviors.

Science.gov (United States)

Agbuga, Bulent; Xiang, Ping; McBride, Ron E

2015-04-21

This study utilized the 2x2 achievement goal model (mastery-approach, mastery-avoidance, performance-approach, performance-avoidance goals) to explore the relationships between achievement goals and self-reported personal and social responsibility behaviors in high school physical education settings. Two hundred and twenty one Turkish students completed questionnaires assessing their achievement goals, personal and social responsibility behaviors. Results of the one-way repeated measures ANOVA revealed significant differences among the four achievement goals, F(3, 660) = 137.05, p social responsibility (r = .38, p responsibility behaviors, and b = .41, t(216) = 5.23, p social responsibility behaviors. These findings seem to provide convergent evidence that mastery-approach goals are positively related to positive educational outcomes.

Performance of a Splittered Transonic Rotor with Several Tip Clearances

Science.gov (United States)

2015-06-15

secondary flows. NOMENCLATURE cp Specific heat capacity at constant pressure [J/kg.K] cv Specific heat capacity at constant volume [J/kg.K] h Enthalpy ...mix Air/water vapor gas mixture o Stagnation or dry-bulb rel Relative humidity ref Standard atmospheric conditions sat Saturated wet bulb...temperature v Water vapor THE SPLITTERED ROTOR The test article in use for this work is the result a larger program to develop a design method and test

Organizational Cultural Factors Hindering Women Ascending to Top Management Positions in Public Universities in Kenya: A Case of Moi University

Science.gov (United States)

Makori, Rebecca S.; Onyango, Maria; Attyang, Judith Miguda; Bantu, Edward; Onderi, Peter Omae

2016-01-01

It is observed that the major setback to economic development in Kenya is stagnation in industrial development. To overcome these, Kenya plans to be a middle level income nation by the year 2030. These plans are to be realized through "Vision 2030." To achieve these goals, Kenya requires gender mainstreamed team of highly skilled workers…

Achieving high milk production performance at grass with minimal concentrate supplementation with spring-calving dairy cows: actual performance compared to simulated performance

OpenAIRE

O'Donovan, M.; Ruelle, Elodie; Coughlan, F.; Delaby, Luc

2015-01-01

The aim of high-profitability grazing systems is to produce milk efficiency from grazed pasture. There is very limited information available on the milk production capacity of dairy cows offered a grass-only diet for the main part of her lactation. In this study, spring-calving dairy cows were managed to achieve high milk production levels throughout the grazing season without supplementation. The calving date of the herd was 12 April; the herd had access to grass as they calved a...

Defensive pessimism, self-esteem and achievement goals: A person-centered approach.

Science.gov (United States)

Ferradás Canedo, María M; Freire Rodríguez, Carlos; Regueiro Fernández, Bibiana; Valle Arias, Antonio

2018-02-01

The relationship between defensive pessimism, self-esteem, and achievement goals is a controversial issue. The main contribution of this research is the adoption of a person-centered approach to explore the existence of differentiated profiles of university students, which combine self-esteem and defensive pessimism. In addition, we analyze whether these profiles differ in their achievement goals (learning, performance-approach, performance-avoidance, and work-avoidance). 1,028 university students took part in the study. Four student profiles were identified: (a) HSE/MDP (high self-esteem and moderate defensive pessimism); (b) LSE/LDP (low self-esteem and low defensive pessimism); (c) HSE/LDP (high self-esteem and low defensive pessimism); and (d) LSE/HDP (low self-esteem and high defensive pessimism). These four profiles differ significantly in their achievement goals. The use of defensive pessimism may involve students with either low or high self-esteem, although the two profiles follow differentiated motivational achievement trajectories.

Academic Self-Concept, Achievement Goals, and Achievement: Is Their Relation the Same for Academic Achievers and Underachievers?

Science.gov (United States)

Preckel, Franzis; Brunner, Martin

2015-01-01

This longitudinal study investigated the contribution of achievement goals and academic self-concept for the prediction of unexpected academic achievement (i.e., achievement that is higher or lower than expected with respect to students' cognitive ability) in general and when comparing groups of extreme over- and underachievers. Our sample…

A Final Report for the Evaluation of the Achieve3000 Programs

Science.gov (United States)

Shannon, Lisa; Grant, Billie-Jo

2015-01-01

Achieve3000 publishes a number of online literacy programs that differentiate lessons and activities based on student performance. Magnolia Consulting--an independent, third party evaluation firm--assessed Achieve3000 Solutions' impact on student learning during the 2014-15 school year. The researchers used a randomized control trial, where…

Characterization of selective solar absorber under high vacuum.

Science.gov (United States)

Russo, Roberto; Monti, Matteo; di Giamberardino, Francesco; Palmieri, Vittorio G

2018-05-14

Total absorption and emission coefficients of selective solar absorbers are measured under high vacuum conditions from room temperature up to stagnation temperature. The sample under investigation is illuminated under vacuum @1000W/m 2 and the sample temperature is recorded during heat up, equilibrium and cool down. During stagnation, the absorber temperature exceeds 300°C without concentration. Data analysis allows evaluating the solar absorptance and thermal emittance at different temperatures. These in turn are useful to predict evacuated solar panel performances at operating conditions.

Raising the stakes: How students' motivation for mathematics associates with high- and low-stakes test achievement.

Science.gov (United States)

Simzar, Rahila M; Martinez, Marcela; Rutherford, Teomara; Domina, Thurston; Conley, AnneMarie M

2015-04-01

This study uses data from an urban school district to examine the relation between students' motivational beliefs about mathematics and high- versus low-stakes math test performance. We use ordinary least squares and quantile regression analyses and find that the association between students' motivation and test performance differs based on the stakes of the exam. Students' math self-efficacy and performance avoidance goal orientation were the strongest predictors for both exams; however, students' math self-efficacy was more strongly related to achievement on the low-stakes exam. Students' motivational beliefs had a stronger association at the low-stakes exam proficiency cutoff than they did at the high-stakes passing cutoff. Lastly, the negative association between performance avoidance goals and high-stakes performance showed a decreasing trend across the achievement distribution, suggesting that performance avoidance goals are more detrimental for lower achieving students. These findings help parse out the ways motivation influences achievement under different stakes.

Establishing and sustaining a technical program to achieve zero fuel failures

International Nuclear Information System (INIS)

Deshon, J.; Whiteside, K.; Burnham, R.

2015-01-01

In 2006, Chief Nuclear Officers (CNOs) of electric utilities operating 103 commercial reactors in the United States (U.S.) formally endorsed an initiative to achieve failure-free fuel performance by the end of 2010. This became known as the Zero-by- Ten Fuel Failure Initiative. The endorsement manifested during a meeting at the Institute of Nuclear Power Operations (INPO) while nuclear fuel performance trends were being reviewed. Declining fuel performance generated backing for the Initiative. This paper provides a brief review of some of the drivers that caused those trends, the Initiative elements designed to address them, and a review of the technical program that helped achieve, and thus far sustain, improved fuel performance. (author) Key Words: Nuclear Fuel, Fuel, Fuel Failures, Fuel Failure Initiative, Zero by Ten Initiative

Attitude Towards Physics and Additional Mathematics Achievement Towards Physics Achievement

Science.gov (United States)

Veloo, Arsaythamby; Nor, Rahimah; Khalid, Rozalina

2015-01-01

The purpose of this research is to identify the difference in students' attitude towards Physics and Additional Mathematics achievement based on gender and relationship between attitudinal variables towards Physics and Additional Mathematics achievement with achievement in Physics. This research focused on six variables, which is attitude towards…

The effect of using digital mind mapping on cognitive achievement and performance level of some basic skills in handball

Directory of Open Access Journals (Sweden)

Khaled Thabet Awad

2016-07-01

Full Text Available This study aims to identify the effect of using digital mind maps to on the cognitive achievement and the performance level of some basic skills in handball. Research population includes the first-year students at the Faculty of Physical Education in Port Said consisting of 200 students. Research Sample both researchers randomly selected the sample of first year students. The total sample size reaches 180 students with a 90.00%, after excluding failed students, re-registered students, the students of other levels of curriculum, practitioners to previous experiences and irregular students. The total number was 20 students with a percentage of (10.00%. They were divided into: Basic Sample: includes 80 students with a 44.44%. They were divided into two equal groups of 40 students. First Exploratory Sample: includes 60 students from the same research population and from outside the basic sample in order to find Tests Validity of the tests with a 33.33%. Second Exploratory Sample: includes 40 students from the same research population and from outside the basic sample in order to find Tests Reliability of the tests and identify the extent of pilot program appropriateness for the sample under discussion with a 22.22%. The first-year students were selected, according to the study plan, which contains a handball curriculum for the students of this educational level. Statistical Treatments: Both researchers conducted data statistically processes, using a statistical package for Social Sciences, SPSS ver. 20.0, in order to identify: arithmetic mean, standard deviation, median, skewness coefficient, correlation coefficient, discriminant validity coefficient, "t" test per one group, "t" test per two groups. The use of mind maps has a positive effect better than (explanation and model method on the cognitive achievement and the performance level of some basic skills in handball. Active learning techniques, such as the method of digital mind maps in teaching

Stereotype threat's effect on women's achievement in chemistry: The interaction of achievement goal orientation for women in science majors

Science.gov (United States)

Conway-Klaassen, Janice Marjorie

"Stereotype threat is being at risk of confirming, as a self-characteristic, a negative stereotype about one's group" (C. M. Steele & Aronson, 1995, p. 797). A stereotype threat effect then is described as the detrimental impact on a person's performance or achievement measurements when they are placed in a stereotype threat environment. For women, the negative stereotype that exists in our culture states that women are typically not as capable as men in mathematics or science subjects. This study specifically explored the potential impact of stereotype threat on women who have chosen a science-based college major. They were tested in the domain of chemistry, which is related to mathematics and often involves high level of mathematics skills. I attempted to generate a stereotype threat in the participants through describing a chemistry challenge exam as either one that had consistently shown a gender bias against women and to create a nullification effect by describing the exam as one that had shown no gender bias in the past. In the third experimental condition acting as a control, participants received only generic instructions related to taking the test itself. The second part of this study investigated whether stereotype threat effects could impact women's achievement goal orientations. In previous studies performance avoidance goal orientations have been associated with individuals placed in a stereotype threat environment. The findings on the stereotype threat effect were not significant for the chemistry challenge test achievement scores. This may be due to several factors. One factor may be the design of the chemistry challenge test and the instructions for the test. The other factor may be the women in this study. As individuals who have chosen a science based major, they may have developed coping skills and strategies that reduced the impact of a stereotype threat. It is also possible that the testing environment itself generated an implicit stereotype

Exploring the relations among physical fitness, executive functioning, and low academic achievement.

Science.gov (United States)

de Bruijn, A G M; Hartman, E; Kostons, D; Visscher, C; Bosker, R J

2018-03-01

Physical fitness seems to be related to academic performance, at least when taking the role of executive functioning into account. This assumption is highly relevant for the vulnerable population of low academic achievers because their academic performance might benefit from enhanced physical fitness. The current study examined whether physical fitness and executive functioning are independent predictors of low mathematics and spelling achievement or whether the relation between physical fitness and low achievement is mediated by specific executive functions. In total, 477 students from second- and third-grade classes of 12 primary schools were classified as either low or average-to-high achievers in mathematics and spelling based on their scores on standardized achievement tests. Multilevel structural equation models were built with direct paths between physical fitness and academic achievement and added indirect paths via components of executive functioning: inhibition, verbal working memory, visuospatial working memory, and shifting. Physical fitness was only indirectly related to low achievement via specific executive functions, depending on the academic domain involved. Verbal working memory was a mediator between physical fitness and low achievement in both domains, whereas visuospatial working memory had a mediating role only in mathematics. Physical fitness interventions aiming to improve low academic achievement, thus, could potentially be successful. The mediating effect of executive functioning suggests that these improvements in academic achievement will be preceded by enhanced executive functions, either verbal working memory (in spelling) or both verbal and visuospatial working memory (in mathematics). Copyright © 2017 Elsevier Inc. All rights reserved.

Stakeholder Engagement: Achieving Sustainability in the Construction Sector

Directory of Open Access Journals (Sweden)

Damian Fearon

2013-02-01

Full Text Available Achieving sustainability-related targets in construction projects is increasingly becoming a key performance driver. Yet sustainability is a complex concept in projects and there are many diverse stakeholders. Some stakeholders are generally recognized as important, i.e., the client and main contractor, yet there are others not always perceived as such and whose absence from the decision-making processes may result in a failure to address sustainability issues. Hence there is a need for a systematic approach to engage with stakeholders with high salience in relation to sustainability. This paper reports the results of an exploratory study involving interviews with construction project practitioners that are involved in sustainability in some way. Data were collected from the practitioners in terms of the processes for engaging with stakeholders to deliver sustainability. The data suggests six steps to a stakeholder engagement process: (i identification; (ii relating stakeholders to different sustainability-related targets; (iii prioritization; (iv managing; (v measuring performance; and (vi putting targets into action. The results suggest that understanding the different sustainability agendas of stakeholders and measuring their performance using key performance indicators are important stages to be emphasized in any stakeholder engagement process to achieve sustainability-related goals.

Pulse Combustor Driven Pressure Gain Combustion for High Efficiency Gas Turbine Engines

KAUST Repository

Lisanti, Joel

2017-02-01

The gas turbine engine is an essential component of the global energy infrastructure which accounts for a significant portion of the total fossil fuel consumption in transportation and electric power generation sectors. For this reason there is significant interest in further increasing the efficiency and reducing the pollutant emissions of these devices. Conventional approaches to this goal, which include increasing the compression ratio, turbine inlet temperature, and turbine/compressor efficiency, have brought modern gas turbine engines near the limits of what may be achieved with the conventionally applied Brayton cycle. If a significant future step increase in gas turbine efficiency is to be realized some deviation from this convention is necessary. The pressure gain gas turbine concept is a well established new combustion technology that promises to provide a dramatic increase in gas turbine efficiency by replacing the isobaric heat addition process found in conventional technology with an isochoric process. The thermodynamic benefit of even a small increase in stagnation pressure across a gas turbine combustor translates to a significant increase in cycle efficiency. To date there have been a variety of methods proposed for achieving stagnation pressure gains across a gas turbine combustor and these concepts have seen a broad spectrum of levels of success. The following chapter provides an introduction to one of the proposed pressure gain methods that may be most easily realized in a practical application. This approach, known as pulse combustor driven pressure gain combustion, utilizes an acoustically resonant pulse combustor to approximate isochoric heat release and thus produce a rise in stagnation pressure.

Final LDRD report : science-based solutions to achieve high-performance deep-UV laser diodes.

Energy Technology Data Exchange (ETDEWEB)

Armstrong, Andrew M.; Miller, Mary A.; Crawford, Mary Hagerott; Alessi, Leonard J.; Smith, Michael L.; Henry, Tanya A.; Westlake, Karl R.; Cross, Karen Charlene; Allerman, Andrew Alan; Lee, Stephen Roger

2011-12-01

We present the results of a three year LDRD project that has focused on overcoming major materials roadblocks to achieving AlGaN-based deep-UV laser diodes. We describe our growth approach to achieving AlGaN templates with greater than ten times reduction of threading dislocations which resulted in greater than seven times enhancement of AlGaN quantum well photoluminescence and 15 times increase in electroluminescence from LED test structures. We describe the application of deep-level optical spectroscopy to AlGaN epilayers to quantify deep level energies and densities and further correlate defect properties with AlGaN luminescence efficiency. We further review our development of p-type short period superlattice structures as an approach to mitigate the high acceptor activation energies in AlGaN alloys. Finally, we describe our laser diode fabrication process, highlighting the development of highly vertical and smooth etched laser facets, as well as characterization of resulting laser heterostructures.

Stereotype Threat's Effect on Women's Achievement in Chemistry: The Interaction of Achievement Goal Orientation for Women in Science Majors

Science.gov (United States)

Conway-Klaassen, Janice Marjorie

2010-01-01

"Stereotype threat is being at risk of confirming, as a self-characteristic, a negative stereotype about one's group" (C. M. Steele & Aronson, 1995, p. 797). A stereotype threat effect then is described as the detrimental impact on a person's performance or achievement measurements when they are placed in a stereotype threat environment. For…

High-Performance All-Polymer Solar Cells Achieved by Fused Perylenediimide-Based Conjugated Polymer Acceptors.

Science.gov (United States)

Yin, Yuli; Yang, Jing; Guo, Fengyun; Zhou, Erjun; Zhao, Liancheng; Zhang, Yong

2018-05-09

We report three n-type polymeric electron acceptors (PFPDI-TT, PFPDI-T, and PFPDI-Se) based on the fused perylene diimide (FPDI) and thieno[3,2- b]thiophene, thiophene, or selenophene units for all-polymer solar cells (all-PSCs). These FPDI-based polymer acceptors exhibit strong absorption between 350 and 650 nm with wide optical bandgap of 1.86-1.91 eV, showing good absorption compensation with the narrow bandgap polymer donor. The lowest unoccupied molecular orbital (LUMO) energy levels were located at around -4.11 eV, which are comparable with those of the fullerene derivatives and other small molecular electron acceptors. The conventional all-PSCs based on the three polymer acceptors and PTB7-Th as polymer donor gave remarkable power conversion efficiencies (PCEs) of >6%, and the PFPDI-Se-based all-PSC achieved the highest PCE of 6.58% with a short-circuit current density ( J sc ) of 13.96 mA/cm 2 , an open-circuit voltage ( V oc ) of 0.76 V, and a fill factor (FF) of 62.0%. More interestingly, our results indicate that the photovoltaic performances of the FPDI-based polymer acceptors are mainly determined by the FPDI unit with a small effect from the comonomers, which is quite different from the others reported rylenediimide-based polymer acceptors. This intriguing phenomenon is speculated as the huge geometry configuration of the FPDI unit, which minimizes the effect of the comonomer. These results highlight a promising future for the application of the FPDI-based polymer acceptors in the highly efficient all-PSCs.

Anxiety and inattention as predictors of achievement in early elementary school children.

Science.gov (United States)

Grills-Taquechel, Amie E; Fletcher, Jack M; Vaughn, Sharon R; Denton, Carolyn A; Taylor, Pat

2013-01-01

The objective of this study was to examine the relations among anxiety, inattention, and math/reading achievement, as well as the mediating/moderating role of inattention in the anxiety-achievement association both concurrently and longitudinally. Participants included 161 ethnically diverse children (aged 6-8) and their teachers. At the middle and end of first grade (approximately 5 months apart), students completed measures of anxiety and achievement while their teachers completed a measure of inattention. For the concurrent analyses, greater harm avoidance anxiety was associated with better attention, which was in turn related to better achievement. For the longitudinal analyses, mid-year inattention interacted with harm avoidance and separation anxiety to predict end of year reading fluency. For those rated as more attentive, greater separation anxiety symptoms were associated with decreased fluency performance while greater harm avoidance symptoms were associated with increased performance. Findings were discussed in terms of the importance of considering socioemotional variables in the study of children's academic achievement and the potential utility of early anxiety prevention/intervention programs, especially for children experiencing academic difficulties who also show internalizing behaviors.

Analysis Of Performance Factors Of Construction Management Consultant Affecting The Failure In Achieving Time And Quality Targets On Construction Project Of Samarinda Baru Airport

OpenAIRE

Maryudi Utomo; Kustamar; Bambang Wedyantadji

2017-01-01

This research aims to determine the performance factors of construction management consultants affecting the failure in achieving time and quality targets on construction project of Samarinda Baru Airport. This research uses survey method by collecting respondents opinion experience and attitude by taking primary data from questionnaires and secondary data from related institutions. The results of the research are 1 Factors directly affecting the Time Target Y1 are the Understanding of Contra...

Breathtaking or stagnation?

DEFF Research Database (Denmark)

Sauer, Johannes; Graversen, Jesper Tranbjerg; Park, Tim

2006-01-01

in technical change as well as a general index model specification. Input specific bias in technical change as well elasticities of input substitution are analyzed. Factors for the development of technical change and the change in efficiency over time are investigated by applying a bootstrapped ITSUR...

Do Children in Montessori Schools Perform Better in the Achievement Test? A Taiwanese Perspective

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Peng, Hsin-Hui; Md-Yunus, Sham'ah

2014-01-01

The study examines whether elementary school students in Taiwan who had received Montessori education achieved significantly higher scores on tests of language arts, math, and social studies than students who attended non-Montessori elementary programs. One hundred ninety six children in first, second, and third grade participated in the study.…

Achieving optimum sports performance during Ramadan: some practical recommendations.

Science.gov (United States)

Maughan, Ronald J; Zerguini, Yacine; Chalabi, Hakim; Dvorak, Jiri

2012-01-01

Muslim athletes should fast from sunrise to sunset each day throughout the 30 days of Ramadan. Most athletes will continue to train throughout Ramadan, and they may also be required to compete at this time, but they will also engage in the religious, cultural, and social activities that Ramadan represents. The available evidence indicates that high-level athletes can maintain performance during Ramadan if physical training, food and fluid intake, and sleep are appropriate and well controlled. Individualized monitoring of athletes may help to prevent fatigue and overtraining and to reduce the risk of consequent illness and injury. The timing and intensity of training may require adjustment to optimize the training response, and training close to or after sunset may have advantages, but this will vary between individual and team sports and between environments that are predominantly Muslim and those that are predominantly non-Muslim. Training late in the day allows nutrition interventions after training to promote adaptations to the training stimulus, to promote recovery, and might help to reduce muscle damage. Sleep deficits have a number of adverse effects on well-being and performance, and athletes should ensure adequate sleep throughout Ramadan. In non-Muslim majority environments, especially in team sports, coaches and athletes should be sensitive to the needs of their team-mates who may be fasting. Event organizers should take account of the needs of Muslim athletes when scheduling the dates and timings of sports competitions.

A numerical performance assessment of a commercial cardiopulmonary by-pass blood heat exchanger.

Science.gov (United States)

Consolo, Filippo; Fiore, Gianfranco B; Pelosi, Alessandra; Reggiani, Stefano; Redaelli, Alberto

2015-06-01

We developed a numerical model, based on multi-physics computational fluid dynamics (CFD) simulations, to assist the design process of a plastic hollow-fiber bundle blood heat exchanger (BHE) integrated within the INSPIRE(TM), a blood oxygenator (OXY) for cardiopulmonary by-pass procedures, recently released by Sorin Group Italia. In a comparative study, we analyzed five different geometrical design solutions of the BHE module. Quantitative geometrical-dependent parameters providing a comprehensive evaluation of both the hemo- and thermo-dynamics performance of the device were extracted to identify the best-performing prototypical solution. A convenient design configuration was identified, characterized by (i) a uniform blood flow pattern within the fiber bundle, preventing blood flow shunting and the onset of stagnation/recirculation areas and/or high velocity pathways, (ii) an enhanced blood heating efficiency, and (iii) a reduced blood pressure drop. The selected design configuration was then prototyped and tested to experimentally characterize the device performance. Experimental results confirmed numerical predictions, proving the effectiveness of CFD modeling as a reliable tool for in silico identification of suitable working conditions of blood handling medical devices. Notably, the numerical approach limited the need for extensive prototyping, thus reducing the corresponding machinery costs and time-to-market. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

The Diffusion of Academic Achievements: Social Selection and Influence in Student Networks

OpenAIRE

Sofia Dokuka; Diliara Valeeva; Maria Yudkevich

2015-01-01

Peer group effects show the influence of student social environments on their individual achievements. Traditionally, a social environment is considered by researchers of peer effects as exogenously given. However, significant peers that affect performance are often those that are deliberately chosen. Students might choose their friends among peers with similar academic achievements. A dynamic analysis of student social networks and academic achievements is needed to disentangle social select...

Co-Relates between Anxiety and Academic Achievement in Teacher Trainees

Science.gov (United States)

Yadav, Shivani; Sharma, Savita

2013-01-01

Anxiety is one of the major predictors of academic performance. Teacher trainees with anxiety disorder display a passive attitude in their studies such as lack of interest in learning, poor performance in exams, and on lesson plans & assignments. This research observes the relationship between level of anxiety and academic achievement of…

Student prosocial behavior and academic achievement

Directory of Open Access Journals (Sweden)

Spasenović Vera Z.

2004-01-01

Full Text Available The paper considers correlation between student prosocial behavior and academic achievement. Attention first focuses on the issue of prosocial behavior defining, making it operational and measuring it. Next consideration is given to the ways that prosocial behavior contributes to academic achievement. It is thought that prosocial behavior can produce indirect effects on student prosocial behavior because it is bound to certain academically relevant forms of behavior leading to successful learning and work. Also, correlation is interpreted by means of teacher’s preferences of prosocial students, which is reflected in teacher expectations and behavior towards students but in evaluating their work too. In addition, prosocial behavior may produce direct effects, for it is through peer prosocial interactions that positive intellectual exchange is performed, which contributes to more successful mastering of teaching content. The paper provides a survey of investigations whose results indicate that there exists correlation between student prosocial behavior and academic achievement. Also, consideration is given to possible methods and treatments for encouraging prosocial behavior in school context, especially the role of teacher in the process and the importance of the program for promoting student prosocial skills.

Numerical investigation on MHD micropolar fluid flow toward a stagnation point on a vertical surface with heat source and chemical reaction

Directory of Open Access Journals (Sweden)

S. Baag

2017-01-01

Full Text Available In this paper, the steady magnetohydrodynamic (MHD mixed convection stagnation point flow of an incompressible and electrically conducting micropolar fluid past a vertical flat plate is investigated. The effects of induced magnetic field, heat generation/absorption and chemical reaction have been taken into account during the present study. Numerical solutions are obtained by using the Runge–Kutta fourth order scheme with shooting technique. The skin friction and rate of heat and mass transfer at the bounding surface are also calculated. The generality of the present study is assured of by discussing the works of Ramachandran et al. (1988, Lok et al. (2005 and Ishak et al. (2008 as particular cases. It is interesting to note that the results of the previous authors are in good agreement with the results of the present study tabulated which is evident from the tabular values. Further, the novelty of the present analysis is to account for the effects of first order chemical reaction in a flow of reactive diffusing species in the presence of heat source/sink. The discussion of the present study takes care of both assisting and opposing flows. From the computational aspect, it is remarked that results of finite difference (Ishak et al. (2008 and Runge–Kutta associated with shooting technique (present method yield same numerical results with a certain degree of accuracy. It is important to note that the thermal buoyancy parameter in opposing flow acts as a controlling parameter to prevent back flow. Diffusion of lighter foreign species, suitable for initiating a destructive reaction, is a suggestive measure for reducing skin friction.

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.

Approximate Arithmetic Training Improves Informal Math Performance in Low Achieving Preschoolers

Directory of Open Access Journals (Sweden)

Emily Szkudlarek

2018-05-01

Full Text Available Recent studies suggest that practice with approximate and non-symbolic arithmetic problems improves the math performance of adults, school aged children, and preschoolers. However, the relative effectiveness of approximate arithmetic training compared to available educational games, and the type of math skills that approximate arithmetic targets are unknown. The present study was designed to (1 compare the effectiveness of approximate arithmetic training to two commercially available numeral and letter identification tablet applications and (2 to examine the specific type of math skills that benefit from approximate arithmetic training. Preschool children (n = 158 were pseudo-randomly assigned to one of three conditions: approximate arithmetic, letter identification, or numeral identification. All children were trained for 10 short sessions and given pre and post tests of informal and formal math, executive function, short term memory, vocabulary, alphabet knowledge, and number word knowledge. We found a significant interaction between initial math performance and training condition, such that children with low pretest math performance benefited from approximate arithmetic training, and children with high pretest math performance benefited from symbol identification training. This effect was restricted to informal, and not formal, math problems. There were also effects of gender, socio-economic status, and age on post-test informal math score after intervention. A median split on pretest math ability indicated that children in the low half of math scores in the approximate arithmetic training condition performed significantly better than children in the letter identification training condition on post-test informal math problems when controlling for pretest, age, gender, and socio-economic status. Our results support the conclusion that approximate arithmetic training may be especially effective for children with low math skills, and that

Approximate Arithmetic Training Improves Informal Math Performance in Low Achieving Preschoolers.

Science.gov (United States)

Szkudlarek, Emily; Brannon, Elizabeth M

2018-01-01

Recent studies suggest that practice with approximate and non-symbolic arithmetic problems improves the math performance of adults, school aged children, and preschoolers. However, the relative effectiveness of approximate arithmetic training compared to available educational games, and the type of math skills that approximate arithmetic targets are unknown. The present study was designed to (1) compare the effectiveness of approximate arithmetic training to two commercially available numeral and letter identification tablet applications and (2) to examine the specific type of math skills that benefit from approximate arithmetic training. Preschool children ( n = 158) were pseudo-randomly assigned to one of three conditions: approximate arithmetic, letter identification, or numeral identification. All children were trained for 10 short sessions and given pre and post tests of informal and formal math, executive function, short term memory, vocabulary, alphabet knowledge, and number word knowledge. We found a significant interaction between initial math performance and training condition, such that children with low pretest math performance benefited from approximate arithmetic training, and children with high pretest math performance benefited from symbol identification training. This effect was restricted to informal, and not formal, math problems. There were also effects of gender, socio-economic status, and age on post-test informal math score after intervention. A median split on pretest math ability indicated that children in the low half of math scores in the approximate arithmetic training condition performed significantly better than children in the letter identification training condition on post-test informal math problems when controlling for pretest, age, gender, and socio-economic status. Our results support the conclusion that approximate arithmetic training may be especially effective for children with low math skills, and that approximate arithmetic

STEM after school programming: The effect on student achievement and attitude

Science.gov (United States)

Ashford, Vanessa Dale

Science, technology, engineering and math (STEM) curriculum has become a major component in to 21st century teaching and learning. STEM skills and STEM careers are in demand globally. Disadvantaged and minority students continue to have an achievement gap in STEM classes. They do not perform well in elementary and middle school and frequently do not pursue STEM-based studies in high school or careers in the field. One innovation in STEM education is after-school programming to increase student interest, attitudes, and achievement. This mixed-methods study examines the Discovery Place After-School STEM Program to compare the achievement levels of participants to non-participants in the program and provides recommendations for STEM after-school programming across the district. As part of the study, teachers were interviewed to examine attitudes and perceptions about the program. This study was conducted at an elementary school in a large urban school district in the southeastern United States which has a unique STEM-based after-school program. Student performance data indicated a significant difference in achievement between participants and non-participants in the program as measured by fifth grade science End-of-Grade test. Data from the seven units of study in the program showed significant achievement for three of the seven units.