WorldWideScience

Sample records for achievement performances stagnate

  1. Transuranics Laboratory, achievements and performance

    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

  2. IMPORTANCE OF ACHIEVEMENT MOTIVATION IN SPORTS PERFORMANCE

    Jyoti A Upadhye; N Chandrappa

    2014-01-01

    The present article defines the psychological construct of Achievement motivation and its influence on Sportsman to achieve their goals and to improve their performance level. Achievement Motivation is a mindset that leads people to set for themselves realistic but challenging goals. In Achievement Motivation can calculate mathematically by taking a person's desire to succeed and subtracting their fear of failure. When a student is motivated, he is inspired to pursue greater a...

  3. IMPORTANCE OF ACHIEVEMENT MOTIVATION IN SPORTS PERFORMANCE

    Jyoti A Upadhye

    2014-06-01

    Full Text Available The present article defines the psychological construct of Achievement motivation and its influence on Sportsman to achieve their goals and to improve their performance level. Achievement Motivation is a mindset that leads people to set for themselves realistic but challenging goals. In Achievement Motivation can calculate mathematically by taking a person's desire to succeed and subtracting their fear of failure. When a student is motivated, he is inspired to pursue greater academic goals. Underlying motivations can include grades, social acceptance or parental approval.

  4. Achievement Goals in a Presentation Task: Performance Expectancy, Achievement Goals, State Anxiety, and Task Performance

    Tanaka, Ayumi; Takehara, Takuma; Yamauchi, Hirotsugu

    2006-01-01

    The aims of the study were to test the linkages between achievement goals to task performance, as mediated by state anxiety arousal. Performance expectancy was also examined as antecedents of achievement goals. A presentation task in a computer practice class was used as achievement task. Fifty-three undergraduates (37 females and 16 males) were…

  5. Achievement Goals, Learning Strategies and Instrumental Performance

    Nielsen, Siw Graabraek

    2008-01-01

    The current study is a survey of the achievement goals of music students and the manner in which their strategies and instrumental performance relate to these goals. In the context of advanced instrumental learning, the rationale for the present study was to contribute to the literature on motivation in music students, and thereby, help teachers…

  6. Impact of Metacognition on Guitar Performance Achievement

    YOKUŞ, Tuba

    2013-01-01

    This study has been carried out to determine the impact of the development of metacognition on guitar performance achievement in the individual instrument guitar lesson, which is included in the Bachelor’s program of Music Teacher Education in Marmara University Atatürk Faculty of Education, Department of Fine Arts Education, in Turkey. “Experimental Design with Pretest–Posttest Control Group” has been used, in order to achieve the objective of the study. The study sample (N=10) consists of g...

  7. Achieving High Performance Perovskite Solar Cells

    Yang, Yang

    2015-03-01

    Recently, metal halide perovskite based solar cell with the characteristics of rather low raw materials cost, great potential for simple process and scalable production, and extreme high power conversion efficiency (PCE), have been highlighted as one of the most competitive technologies for next generation thin film photovoltaic (PV). In UCLA, we have realized an efficient pathway to achieve high performance pervoskite solar cells, where the findings are beneficial to this unique materials/devices system. Our recent progress lies in perovskite film formation, defect passivation, transport materials design, interface engineering with respect to high performance solar cell, as well as the exploration of its applications beyond photovoltaics. These achievements include: 1) development of vapor assisted solution process (VASP) and moisture assisted solution process, which produces perovskite film with improved conformity, high crystallinity, reduced recombination rate, and the resulting high performance; 2) examination of the defects property of perovskite materials, and demonstration of a self-induced passivation approach to reduce carrier recombination; 3) interface engineering based on design of the carrier transport materials and the electrodes, in combination with high quality perovskite film, which delivers 15 ~ 20% PCEs; 4) a novel integration of bulk heterojunction to perovskite solar cell to achieve better light harvest; 5) fabrication of inverted solar cell device with high efficiency and flexibility and 6) exploration the application of perovskite materials to photodetector. Further development in film, device architecture, and interfaces will lead to continuous improved perovskite solar cells and other organic-inorganic hybrid optoelectronics.

  8. Capital Accumulation and the Dynamics of secular stagnation

    Le Garrec, Gilles; Touze, Vincent

    2016-01-01

    We characterize the dynamics of secular stagnation as a permanent regime switching from a full employment equilibrium to an underemployment equilibrium. In the latter, the natural interest rate is negative, and the economy is in deáation. Due to the non negativity condition imposed on policy rate, the zero lower bond (ZLB) applies which prevents targeting ináation. The secular stagnation equilibrium is achieved in a standard overlapping generations model with capital accumulati...

  9. Achieving Performance-based Lifecycle Management

    Louis Kratz; Bradd Buckingham

    2009-01-01

    Currently, the US faces significant economic and national security threats from near- peer competitors, rogue states, and transnational terrorist organizations. This multiplicity of threats requires an agile, cost-efficient process to mature and sustain military capabilities. A fundamental change to DoD lifecycle management is required to achieve that necessary agility. This paper explores fundamental changes within government and industry to evolve a highly agile and responsive lifecycle pro...

  10. 'High' Achievers? Cannabis Access and Academic Performance

    Marie, Olivier; Zölitz, Ulf

    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 panel data on over 54,000 course grades of local students enrolled at Maastricht University before and during the partial cannabis prohibition. We find that the academic performance of students who a...

  11. User-Level Device Drivers: Achieved Performance

    Ben Leslie; Gernot Heiser; Peter Chubb; Nicholas Fitzroy-Dale; Stefan G(o)tz; Charles Gray; Luke Macpherson; Daniel Potts; Yue-Ting Shen; Kevin Elphinstone

    2005-01-01

    Running device drivers as unprivileged user-level code, encapsulated into their own process, has often been proposed as a technique for increasing system robustness. However, in the past, systems based on user-level drivers have generally exhibited poor I/O performance. Consequently, user-level device drivers have never caught on to any significant degree. In this paper we demonstrate that it is possible to build systems which employ user-level device drivers, without significant performance degradation, even for high-bandwidth devices such as Gigabit Ethernet.

  12. Achieving outage excellence through partnership in performance

    This paper discusses the joint efforts of Public Service of New Jersey and Westinghouse aimed at attaining excellence in outage performance. Success in the 1986 outages at Salem Units 1 and 2 was accomplished by joint efforts in detailed initial communication and planning, tough goal setting, communication of objectives, identification of responsibility, incentive structuring, and finally, by hard work by both organizations aimed at working the plan and minimizing impacts where changes were required during the outage

  13. Using the 2 x 2 Framework of Achievement Goals to Predict Achievement Emotions and Academic Performance

    Putwain, David W.; Sander, Paul; Larkin, Derek

    2013-01-01

    Previous work has established how achievement emotions are related to the trichotomous model of achievement goals, and how they predict academic performance. In our study we examine relations using an additional, mastery-avoidance goal, and whether outcome-focused emotions are predicted by mastery as well as performance goals. Results showed that…

  14. Buoyancy, bending, and seismic visibility in deep slab stagnation

    Bina, Craig R.; Kawakatsu, Hitoshi; Suetsugu, D.; Bina, C.; Inoue, T.; Wiens, D.; Jellinek, M.

    2010-11-01

    The petrological consequences of deep subhorizontal deflection ("stagnation") of subducting slabs should affect both apparent seismic velocity structures and slab morphology. We construct kinematic thermal models of stagnant slabs and perform thermodynamic modeling of the consequent perturbation of high-pressure phase transitions in mantle minerals, focusing upon Japan as our study area. We calculate associated thermo-petrological buoyancy forces and bending moments which (along with other factors such as viscosity variations and rollback dynamics) may contribute to slab deformation. We consider effects of variations in depth of stagnation, post-stagnation dip angle, phase transition sharpness, transition triplication due to multiple intersection of geotherms with phase boundaries, and potential persistence of metastable phases due to kinetic hindrance. We also estimate seismic velocity anomalies, as might be imaged by seismic tomography, and corresponding seismic velocity gradients, as might be imaged by receiver-function analysis. We find that buoyant bending moment gradients of petrological origin at the base of the transition zone may contribute to slab stagnation. Such buoyancy forces vary with the depth at which stagnation occurs, so that slabs may seek an equilibrium slab stagnation depth. Metastable phase bending moment gradients further enhance slab stagnation, but they thermally decay after ∱/4600•700 km of horizontal travel, potentially allowing stagnant slabs to descend into the lower mantle. Stagnant slabs superimpose zones of negative velocity gradient onto a depressed 660-km seismic discontinuity, affecting the seismological visibility of such features. Seismologically resolvable details should depend upon both stagnation depth and the nature of the imaging technique (travel-time tomography vs. boundary-interaction phases). While seismic tomography appears to yield images of stagnant slabs, discontinuity topography beneath Japan resolved by

  15. Classroom Environment, Achievement Goals and Maths Performance: Gender Differences

    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 assessed as…

  16. A Model of Statistics Performance Based on Achievement Goal Theory.

    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.)…

  17. Total Performance Scorecard Redefining Management to Achieve Performance with Integrity

    Rampersad, Hubert

    2003-01-01

    In the post-Enron climate corporate executives are increasingly pressured to increase productivity and create an ethical, trustworthy organizational climate. 'Total Performance Scorecard' introduces a concept of organizational improvement and change management that combines the Balanced Scorecard model with the learning organization theory. The TPS contains a personal balanced scorecard, which is tied to an organizational balanced scorecard. These scorecards reflect not only performance goals but personal learning and growth goals as well, and the organizational scorecards also address organiz

  18. Solar wind stagnation near comets

    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)

  19. Secular Stagnation: Theory and Remedies

    Michau, Jean-Baptiste

    2015-01-01

    This paper relies on a Ramsey model with money to o¤er a simple theory of secular stagnation. The permanent failure of the economy to produce at full capacity results from three features: (i) The combination of the zero lower bound on the nominal interest rate and of an in ‡ation ceiling imposes a lower bound on the real interest rate; (ii) Some dynastic households have a high propensity to save, due to a preference for wealth; (iii) A downward wage rigidity breaks the de ‡ationary spiral res...

  20. School Performance Indicators, Accountability Ratings, and Student Achievement

    Jackson, Shirley A.; Lunenburg, Fred C.

    2010-01-01

    Researchers have been challenged to find school-level characteristics that make a difference in student achievement. This study focused on a diverse sample of 24 middle schools to examine differences between schools rated Exemplary, Recognized, Academically Acceptable, and Academically Unacceptable on four performance indicator dimensions:…

  1. Performance Achievement and Analysis of Teaching during Choral Rehearsals.

    Davis, Anita P.

    1998-01-01

    Evaluates teaching sequences in high-school choral rehearsals to provide insight into the relationship between ensemble achievement and performance preparation. Indicates that teacher pace improvement is unrelated to ensemble maturity, teacher verbalization may not relate to success, and teacher assistance and instructions decrease with student…

  2. How to Achieve Quality Business Performance in an Organization

    Merima Bekri ć

    2013-01-01

    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'...

  3. The Role Of The Budgetary System In Achieving Enterprise Performance

    Adriana Mihaela Ionescu

    2014-05-01

    Full Text Available The long-term existence of an enterprise can only be assured by achieving of the performance.In the current economic climate, the companies pay more attention to effective management of resources and use for this purpose different management tools of performance. Along with material and financial resources necessary to productive activities, the people in an organization represent more than a source of cost or consumption. Their systems of needs and values, along with degrees of motivation and satisfaction determine individual and organizational performance. This is why the managers are tasked to reconcile and correlate the economic performance of the organization with the skills and capabilities of the employees. Flexible approach to business organization and permanent training of the human resources are the ingredients of success of an enterprise that aims to adapt to the current business environment changes.

  4. Achievement goals and championship performance: Predicting absolute performance and qualification success

    Stoeber, Joachim; Crombie, Rosanna

    2010-01-01

    Objectives: Research on athletes’ achievement goals has suggested that the contrast between performance approach and performance avoidance goals (performance approach-avoidance contrast) is a significant predictor of sports performance. However, so far only two studies investigating triathletes found that performance approach-avoidance contrast predicted sports performance in competitions. The present study aims to replicate and expand on these findings with a diverse sample of track and fiel...

  5. 晋升机会缺失对员工工作绩效的影响--内在动机与内部地位感知的中介作用%Promotion Opportunity Stagnation and Job Performance:the Mediating---Role of Intrinsic Motivation and Perceived Insider Status

    廖建桥; 景珍思; 刘文兴; 汪兴东

    2015-01-01

    This study tries to explore the side back of promotion opportunity stagnation, assuming that promotion opportunity stagnation should be one important factor of inhibiting employee j ob performance,and that the effect of promotion opportunity stagnation on j ob performance should be mediated by intrinsic motivation and perceived insider status.By the answers to the questionnaires and the analysis of 354 samples from a large installation company in China,the results indicated that,(1 )promotion opportunity stagnation had negative effects on employee j ob performance;(2 )promotion opportunity stagnation had negative effects on intrinsic motivation and perceived insider status;(3 )both intrinsic motivation and perceived insider status had positive effects on employee j ob performance;(4 )both intrinsic motivation and perceived insider status fully mediated the relationship between promotion opportunity stagnation and j ob performance.At last,we discuss implications of these results for research and practice and future directions.%探讨晋升机会缺失的负面影响,认为晋升机会缺失是阻碍员工工作绩效提升的重要影响因素,且晋升机会缺失是通过内在动机与内部地位感知最终影响到员工工作绩效。通过对来自一家大型安装企业的354名员工实证分析结果表明:①晋升机会缺失会显著降低员工工作绩效;②晋升机会缺失会显著降低内在动机与内部地位感知;③内在动机、内部地位感知显著正面影响员工工作绩效;④晋升机会缺失通过内在动机、内部地位感知,进而降低员工工作绩效。最后,讨论了相关理论和实践的启示以及未来的研究方向。

  6. From Stagnation to Growth: Unified Growth Theory

    Galor, Oded

    2004-01-01

    This chapter examines the process of development from an epoch of Malthusian stagnation to a state of sustained economic growth. The analysis focuses on recently advanced unified growth theories that capture the intricate evolution of income per capita, technology, and population over the course of human history. Deciphering the underlying forces that triggered the transition from stagnation to growth and the associated phenomenon of the great divergence in income per capita across countries ...

  7. How to Achieve Quality Business Performance in an Organization

    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.

  8. Vorticity amplification near the stagnation point of landing gear wheels

    Feltham, G.; Ekmekci, A.

    2014-04-01

    The vicinity near the forward stagnation point of landing-gear wheels has been found to support a mechanism for oncoming streams of weak vorticity to collect, grow, and amplify into discrete large-scale vortical structures that then shed with a distinct periodicity. To the authors' knowledge, such a flow phenomenon has never been reported before for landing gear wheels, which are in essence finite (three-dimensional) cylinders. To gain further insight into this phenomenon, a detailed experimental study has been undertaken employing the hydrogen bubble visualization and Particle Image Velocimetry techniques. A very thin platinum wire, similar to those used in hydrogen bubble visualization applications, was placed upstream of the wheel model to produce two streams of weak vorticity (with opposite sign) that convected toward the model. As the vorticity streams enter the stagnation region of the wheels, significant flow deceleration and vorticity stretching act to collect, grow, and amplify the incoming vorticity streams into large-scale vortical structures. Experiments were performed at a fixed Reynolds number, with a value of 32 500 when defined based on the diameter of the wheel and a value of 21 based on the diameter of the vorticity-generating upstream wire. First, to establish a baseline, the natural flow field (without the presence of an upstream wire) was characterized, where experimentally determined values for the stagnation boundary-layer thickness and the velocity profile along the stagnation streamline were both found to agree with the values provided in the literature for two-dimensional cylinders. Subsequently, the dynamics of vorticity collection, growth, amplification, and shedding were studied. The size, stand-off distance and the shedding frequency of the vortical structures forming near the stagnation region were all found to strongly depend on the impingement location of the inbound vorticity on the wheel. A simple relationship between the non

  9. Science Achievement for All: Improving Science Performance and Closing Achievement Gaps

    Jackson, Julie K.; Ash, Gwynne

    2012-01-01

    This article addresses the serious and growing need to improve science instruction and science achievement for all students. We will describe the results of a 3-year study that transformed science instruction and student achievement at two high-poverty ethnically diverse public elementary schools in Texas. The school-wide intervention included…

  10. Achieving fast timing performance with multiplexed SiPMs

    Bieniosek, M. F.; Cates, J. W.; Levin, C. S.

    2016-04-01

    Using time of flight (ToF) measurements for positron emission tomography (PET) is an attractive avenue for increasing the signal to noise (SNR) ratio of PET images. However, achieving excellent time resolution required for high SNR gain using silicon photomultipliers (SiPM) requires many resource heavy high bandwidth readout channels. A method of multiplexing many SiPM signals into a single electronic channel would greatly simplify ToF PET systems. However, multiplexing SiPMs degrades time resolution because of added dark counts and signal shaping. In this work the relative contribution of dark counts and signal shaping to timing degradation is simulated and a baseline correction technique to mitigate the effect of multiplexing on the time resolution of analog SiPMs is simulated and experimentally verified. A charge sharing network for multiplexing is proposed and tested. Results show a full width at half maximum (FWHM) coincidence time resolution of 232+/- 2 ps for a single 3 mm  ×  3 mm  ×  20 mm LYSO scintillation crystals coupled to an array of sixteen 3 mm  ×  3 mm SiPMs that are multiplexed to a single timing channel (in addition to 4 position channels). A 4× 4 array of 3 mm  ×  3 mm  ×  20 mm LFS crystals showed an average FWHM coincidence time resolution of 278+/- 7 ps using the same timing scheme. All experiments were performed at room temperature with no thermal regulation. These results show that excellent time resolution for ToF can be achieved with a highly multiplexed analog SiPM readout.

  11. Approximate Model for Turbulent Stagnation Point Flow.

    Dechant, Lawrence [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-01-01

    Here we derive an approximate turbulent self-similar model for a class of favorable pressure gradient wedge-like flows, focusing on the stagnation point limit. While the self-similar model provides a useful gross flow field estimate this approach must be combined with a near wall model is to determine skin friction and by Reynolds analogy the heat transfer coefficient. The combined approach is developed in detail for the stagnation point flow problem where turbulent skin friction and Nusselt number results are obtained. Comparison to the classical Van Driest (1958) result suggests overall reasonable agreement. Though the model is only valid near the stagnation region of cylinders and spheres it nonetheless provides a reasonable model for overall cylinder and sphere heat transfer. The enhancement effect of free stream turbulence upon the laminar flow is used to derive a similar expression which is valid for turbulent flow. Examination of free stream enhanced laminar flow suggests that the rather than enhancement of a laminar flow behavior free stream disturbance results in early transition to turbulent stagnation point behavior. Excellent agreement is shown between enhanced laminar flow and turbulent flow behavior for high levels, e.g. 5% of free stream turbulence. Finally the blunt body turbulent stagnation results are shown to provide realistic heat transfer results for turbulent jet impingement problems.

  12. Cryogenics system: strategy to achieve nominal performance and reliable operation

    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)

  13. Performance-Based Pay as a Motivational Tool for Achieving Organisational Performance: An Exploratory Case Study

    Francis Boachie-Mensah; Ophelia Delali Dogbe

    2011-01-01

    The issue of employees’ performance in furtherance of organisational objectives has occupied managementattention for long. Differences in levels of performance have been attributed to differences in skills and abilitieson the one hand, and to different theories of money on the other. This study examined the issue ofperformance-based pay as a motivational tool for achieving organisational performance, using the situation in amanufacturing company in Ghana as a case study. The main objective of...

  14. Safety and performance achievement of Indian nuclear power plant

    Full text: The Nuclear power programme in India at present is based mainly on series of pressurized heavy water reactor(PHWR). Starting from Rajesthan atomic power station comprising two unit of 200 MWe in 1973, the programme has come a long way with 17 units in operation includes two unit of 540 MWe at Turapur 3 and 4. Narora atomic power station commissioned in 1991 marked major indigenization and standardization of PHWR design. Which includes, double containment of reactor building, two diverse reactor protection system and emergency core cooling system. Further in 540 MWe at Tarapur, the safety systems have been divided into two groups to the extent possible. These groups are physically separated so that any common mode incident either inside or outside the reactor building would nor disabled more than one of these groups. Each group of safety system should meet the requirements of shutdown the reactor , remove decay heat from the fuel subsequent to shutdown, prevent any subsequent escalation of failures, minimize the escape of radioactivity, supply necessary information to the operators for assesment of the state of the plant. Group-1 is first line of defense safety systems i.e. Shut Down System-1 (SDS-1), Emergency Core Cooling System (ECCS) and all process water systems including shutdown cooling. Group-2 is the second safety systems i.e. Shut Down System-2 (SDS-2), containment isolation, Moderator cooling, Emergency water supply (fire fighting water with diesel driven pump) through Steam Generator. Status of the plant is monitored and controlled from Main Control Room (MCR) and it is done from supplementary control room in case of emergency. Each safety system is designed to achieve unavailability of 10-3 year/year or less. Indian nuclear power plant progressively attained excellent operation performance comparable to international benchmark with sustained efforts in operation and maintenance, development and nurturing of qualified human resources at

  15. Concurrently adjusting interrelated control parameters to achieve optimal engine performance

    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.

  16. Orchestrating ACO success: how top performers achieve shared savings.

    Harris, John M; Elizondo, Idette; Brown, Amanda M

    2016-03-01

    Leaders of the top-performing accountable care organizations in the Medicare Shared Savings Program attribute the success of their organizations in large part to seven strategies: Seek action-oriented leadership. Transform primary care physician practices. Keep patients out of the emergency department. Ensure all transitions are smooth. Make effective use of available data. Share information on physician performance. Keep patients engaged. PMID:27183758

  17. Secular stagnation and progressive economic policy alternatives

    Onaran, Özlem

    2016-01-01

    This paper summarizes two main findings in the Post-Keynesian literature regarding the linkages between financialization, income distribution, accumulation and productivity. Firstly, at the core of secular stagnation lies the missing link between profits and investment. Secondly, rising inequality and financialization have been the main reasons for this missing link and hence the major brakes against capital accumulation and growth. The paper concludes with alternative progressive policies b...

  18. Cryogenics system: strategy to achieve nominal performance and reliable operation

    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 ...

  19. Effect of bed configuration on pebble flow uniformity and stagnation in the pebble bed reactor

    Highlights: • Pebble flow uniformity and stagnation characteristics are very important for HTR-PM. • Arc- and brachistochrone-shaped configuration effects are studied by DEM simulation. • Best bed configurations with uniform flow and no stagnated pebbles are suggested. • Detailed quantified characteristics of bed configuration effects are shown for explanation. - Abstract: Pebble flow uniformity and stagnation characteristics are very important for the design of pebble bed high temperature gas-cooled reactor. Pebble flows inside some specifically designed contraction configurations of pebble bed are studied by discrete element method. The results show the characteristics of stagnation rates, recycling rates, radial distribution of pebble velocity and residence time. It is demonstrated clearly that the bed with a brachistochrone-shaped configuration achieves optimum levels of flow uniformity and recycling rate concentration, and almost no pebbles are stagnated in the bed. Moreover, the optimum choice among the arc-shaped bed configurations is demonstrated too. Detailed information shows the quantified characteristics of bed configuration effects on flow uniformity. In addition, a good design of the pebble bed configuration is suggested

  20. Teacher Performance and Pupil Achievement on Teacher-Made Tests.

    Ellett, Chad D.; And Others

    This study investigated the predictive validity of the Teacher Performance Assessment Instruments (TPAI) using pupil gains on teacher-made tests (TMT) as a criterion. The TPAI and the TMT's were administered to 56 elementary and secondary classrooms in Georgia. Results supported the validity of the TPAI with a large number of correlations ranging…

  1. Achieving Mixtures of Ultra-High Performance Concrete

    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.

  2. Achieving Improved Performance at Access Point in WLAN Infrastructure Mode

    Irfan Siddavatam

    2011-07-01

    Full Text Available In recent years WLAN is projecting itself as alternate solution to carry out enterprise’s network traffic. The basic mode of WLAN is classified as ad-hoc mode and infrastructure mode. Infrastructure mode use wired network as backbone. The enterprise WLAN network design preferred infrastructure mode which assume as extension to wired network. The wireless access point is major component of infrastructure mode. As demand for every type of traffic increases in WLAN, how access point handles this traffic grabs equal attention. Study of access point varies at different layers such as location of access point at physical layer, queuing mechanism of access point at Mac layer. In this paper we discus role of access point in handling WLAN traffic and shortcoming of existing approach. In this paper alternative approach for access point is suggested to approve network performance using learning method.

  3. WEIGHTS STAGNATION IN DYNAMIC LOCAL SEARCH FOR SAT

    Abdelraouf Ishtaiwi

    2016-05-01

    Full Text Available Since 1991, tries were made to enhance the stochastic local search techniques (SLS. Some researchers turned their focus on studying the structure of the propositional satisfiability problems (SAT to better understand their complexity in order to come up with better algorithms. Other researchers focused in investigating new ways to develop heuristics that alter the search space based on some information gathered prior to or during the search process. Thus, many heuristics, enhancements and developments were introduced to improve SLS techniques performance during the last three decades. As a result a group of heuristics were introduced namely Dynamic Local Search (DLS that could outperform the systematic search techniques. Interestingly, a common characteristic of DLS heuristics is that they all depend on the use of weights during searching for satisfiable formulas. In our study we experimentally investigated the weights behaviors and movements during searching for satisfiability using DLS techniques, for simplicity, DDFW DLS heuristic is chosen. As a results of our studies we discovered that while solving hard SAT problems such as blocks world and graph coloring problems, weights stagnation occur in many areas within the search space. We conclude that weights stagnation occurrence is highly related to the level of the problem density, complexity and connectivity.

  4. Stagnation Point Radiative Heating Relations for Venus Entry

    Tauber, Michael E.; Palmer, Grant E.; Prabhu, Dinesh K.

    2012-01-01

    Improved analytic expressions for calculating the stagnation point radiative heating during entry into the atmosphere of Venus have been developed. These analytic expressions can be incorporated into entry trajectory simulation codes. Together with analytical expressions for convective heating at the stagnation point, the time-integrated total heat load at the stagnation point is used in determining the thickness of protective material required, and hence the mass of the fore body heatshield of uniform thickness.

  5. Stagnation, circulation, and erosion of granular materials through belt conveyor sluice gate

    Pohlman, Nicholas; Moralda, Michael; Dunne, Ryan

    2013-11-01

    Control of flow rates in conversion reactors for discrete materials like biomass can be achieved in belt conveyors through a combination of belt speed, hopper size, and aperture opening. As material is extracted from the bottom of the storage hopper, other material cannot achieve plug flow and therefore is restricted from exiting through a sluice-gate type opening. The excess material moves vertically from the opening causing a pile up and recirculation back along the free surface of the hopper. Experimental results obtained through high speed imaging show the position of the stagnation point as well as the rate of circulation is dependent on the mass flow rate achieved and instantaneous fill level. The movement of material into the plug flow along the belt allows verification of deposition models on erodible beds rather than rigid surfaces with artificial roughness of glued particles. Similarly, the pile-up at the exit influences the efficiency of the transport affecting the narrow energy return on investment of biomass resources. The laboratory-scale behavior can therefore be translated into industrial performance metrics for increased operational efficiency. This work is supported by the NSF REU Site Operation E-Tank under award number 1156789.

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

    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…

  7. Boredom in achievement settings : exploring control-value antecedents and performance outcomes of a neglected emotion

    Pekrun, Reinhard; Götz, Thomas; Daniels, Lia Marie; 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 boredom (i.e., trait achievement boredom). Samples consisted of university students from two different cultural contexts (North America and Germany). In l...

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

    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…

  9. Orality disorders in melancholia: acedia as stagnation

    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.

  10. Analysis of performance instruction delivery methods on student achievement in principles of marketing

    Brown, Bruce Edward

    1994-01-01

    This study investigated the use of alternative performance instruction delivery methods on student achievement in a Principles of Marketing course taught at New River Community College during the 1993 fall semester. The study sought to determine if alternative delivery methods of performance instruction would influence students' achievement in the course. The design of the study was quasi-experimental. Two treatment groups were engaged by this study. One group received performance instr...

  11. Simulations of the implosion and stagnation of compact wire arrays

    Wire array z-pinches have been used successfully for many years as a powerful x-ray source, as a dynamic hohlraum, and as an intense K-shell radiation source. Significant progress has been made in the effective modeling of these three-dimensional (3D) resistive plasmas. However, successful modeling also requires an accurate representation of the power delivered to these loads from the generator, which is an uncertainty potentially as large as the magnetohydrodynamic (MHD) implosion dynamics. We present 3D resistive MHD simulations of wire arrays that are coupled to transmission line equivalent models of the Z generator, driven by voltage sources derived directly from electrical measurements. Significant (multi-mega-ampere) current losses are shown to occur in both the convolute and the final feed. This limits the array performance and must be correctly accounted for to accurately represent the generator response to the load. Our simulations are validated against data for compact: 20 mm diameter, 10 mm long wire arrays that have produced the highest x-ray power densities on Z. This is one of the most comprehensive experimental data sets for single and nested wire arrays and includes voltage, current, x-ray power and energy, and multiple mass distribution measurements. These data tightly constrain our simulation results and allow us to describe in detail both the implosion and stagnation, and how energy is delivered to, and radiated from z-pinch loads. We show that the radiated power is consistent with the kinetic energy delivered to a distributed 3D mass profile over its implosion and stagnation. We also demonstrate how the local inductance of the transmission line connecting to the wire array is responsible for delivering more than 50% of the total radiated power. This makes the power output dependent on the design of specific elements of the generator, and their response to the imploding load, and not just on the peak current that can be delivered.

  12. On impulsively started convection: The case of stagnation point flow

    Ramadan, K. [Department of Mechanical Engineering, Mu' tah University, P. O. Box 7, Karak 61710 (Jordan); Al-Nimr, M.A. [Department of Mechanical Engineering, Jordan University of Science and Technology, P. O. Box 3030, Irbid 22110 (Jordan)

    2011-12-15

    Transient convection in incompressible planar and axisymmetric point flow is analyzed numerically in this work, and the thermal boundary layer response to surface sudden heating and cooling in the two settings is presented and compared over a range of Prandtl number between 0.5 and 100. A comparison between surface sudden cooling and heating is performed and different criteria are established as to when surface sudden heating and cooling are equivalent in terms of the transition time. With no initial thermal boundary layer (surface and fluid are at the same temperature), the transition time from the initial steady state to the final steady state upon surface sudden cooling or heating is found to be a constant regardless of the surface heating or cooling extent above or below the initial surface temperature, and is dependent only on the Prandtl number. With the existence of an initial thermal boundary layer, the transition time is dependent upon the heating or cooling extent, the initial surface temperature, the Prandtl number and whether heating/cooling is towards building-up or demolishing the thermal boundary later. It takes longer time when surface sudden heating or cooling is towards demolishing the thermal boundary layer than building it up. With symmetric surface sudden cooling or heating above or below the far-field fluid temperature, the transition time is independent on the surface cooling or heating extent and is a function of only the Prandtl number. A considerable difference in the thermal boundary layer response in the two settings is found. The transition time from the initial to the final steady state in axisymmetric stagnation point flow is less than that in plane stagnation flow under the same conditions. (authors)

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

    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 similaritie...

  14. Do Performance Goals Promote Learning? A Pattern Analysis of Singapore Students' Achievement Goals

    Luo, Wenshu; Paris, Scott G.; Hogan, David; Luo, Zhiqiang

    2011-01-01

    This study investigated how achievement goals are combined to affect students' learning. We used a multiple goals perspective, based on mastery (i.e., mastery approach) and performance (including both approach and avoidance components) goals, to examine the achievement goal patterns of 1697 Singapore Secondary 3 students in their math study. Four…

  15. Positive Biases in Self-Assessment of Mathematics Competence, Achievement Goals, and Mathematics Performance

    Dupeyrat, Caroline; Escribe, Christian; Huet, Nathalie; Regner, Isabelle

    2011-01-01

    The study examined how biases in self-evaluations of math competence relate to achievement goals and progress in math achievement. It was expected that performance goals would be related to overestimation and mastery goals to accurate self-assessments. A sample of French high-school students completed a questionnaire measuring their math…

  16. The association between physical activity, cognitive performance, and academic achievement in adolescents

    Van Dijk, Martin; De Groot, Renate; Kirschner, Paul A.

    2011-01-01

    Van Dijk, M. L., De Groot, R. H. M., Kirschner, P. A. (2011, 24 March). The association between physical activity, cognitive performance, and academic achievement in adolescents. Presentation at the ICO Introduction course, Utrecht, The Netherlands.

  17. The GOALS Study: The association between physical activity, cognitive performance, and academic achievement in adolescents

    Van Dijk, Martin; De Groot, Renate; Kirschner, Paul A.

    2011-01-01

    Van Dijk, M. L., De Groot, R. H. M., & Kirschner, P. A. (2011, 26 April). The GOALS Study: The association between physical activity, cognitive performance, and academic achievement in adolescents. Presentation at the Learning & Cognition meeting, Heerlen, The Netherlands.

  18. Neuropsychological and Academic Achievement Correlates of Abnormal WISC-R Verbal-Performance Discrepancies.

    Lueger, Robert J.; And Others

    1985-01-01

    Examined neuropsychological and academic achievement correlates of statistically abnormal verbal-performance discrepancies on the Wechsler Intelligence Scale for Children (Revised). Results indicated that abnormal discrepancies reflect specific aphasia deficits rather than generalized neuropsychological dysfunction and that academic achievement…

  19. Perfectionism and aptitude test performance: Testees who strive for perfection achieve better test results

    Stoeber, Joachim; Kersting, Martin

    2007-01-01

    Positive conceptions of perfectionism (Stoeber & Otto, 2006) suggest that perfectionistic strivings may form part of a healthy pursuit of excellence and are associated with higher academic achievement and higher performance in laboratory tasks. To extend such research findings, the present study explores if perfectionistic strivings also predict aptitude test performance, while controlling for conscientious achievement striving. A sample of 111 participants, who completed measures of perfecti...

  20. Achieving Flexibility and Performance for Packet Forwarding and Data Center Management

    Moon, Daekyeong

    2010-01-01

    Although today's networking equipment has achieved high performance and low cost by embedding forwarding logic in hardware, this has come at the price of severely reduced flexibility. In this dissertation, we address the problem of achieving both flexibility and performance in two networking domains: packet forwarding and data center networking. In packet forwarding, we present Software Defined Forwarding, a hybrid design that attempts to combine the high speed and low cost of hardware with ...

  1. Regulating Debilitating Emotions in the Context of Performance: Achievement Goal Orientations, Achievement-Elicited Emotions, and Socialization Contexts

    Tyson, Diana F.; Linnenbrink-Garcia, Lisa; Hill, Nancy E.

    2009-01-01

    A theoretical framework that incorporates emotional responses and emotion regulation into achievement goal theory is proposed as an alternative view to understanding the inconsistent pattern of findings linking achievement goal orientations to academic outcomes. In this critical review and synthesis, the relation of achievement goal orientations…

  2. Microfluidic extensional rheometry using stagnation point flow.

    Haward, S J

    2016-07-01

    Characterization of the extensional rheometry of fluids with complex microstructures is of great relevance to the optimization of a wide range of industrial applications and for understanding various natural processes, biological functions, and diseases. However, quantitative measurement of the extensional properties of complex fluids has proven elusive to researchers, particularly in the case of low viscosity, weakly elastic fluids. For some time, microfluidic platforms have been recognized as having the potential to fill this gap and various approaches have been proposed. This review begins with a general discussion of extensional viscosity and the requirements of an extensional rheometer, before various types of extensional rheometers (particularly those of microfluidic design) are critically discussed. A specific focus is placed on microfluidic stagnation point extensional flows generated by cross-slot type devices, for which some important developments have been reported during the last 10 years. Additional emphasis is placed on measurements made on relevant biological fluids. Finally, the operating limits of the cross-slot extensional rheometer (chiefly imposed by the onset of elastic and inertial flow instabilities) are discussed. PMID:27099647

  3. The effect of adaptive performance support system on learning achievements of students

    Kommers, Piet; Stoyanov, Slavi; Mileva, Nevena; Martinez Mediano, Catalina

    2008-01-01

    The study compares the effectiveness of two performance support systems, adaptive and non-adaptive, on learning achievements of engineering students. In addition, the research design controls for a possible effect of learning style. The analysis reveals that students working with an adaptive performance support system score significantly higher than students using a non-adaptive performance system on a performance test across different learning styles. The only variation in the two experiment...

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

    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

  5. On Thin Ice: CESEE Core Resilient in the Face of EU Stagnation and the Ukraine Crisis

    Vasily Astrov; Serkan Çiçek; Rumen Dobrinsky; Vladimir Gligorov; Doris Hanzl-Weiss; Peter Havlik; Mario Holzner; Gabor Hunya; Sebastian Leitner; Olga Pindyuk; Leon Podkaminer; Sandor Richter; Hermine Vidovic

    2014-01-01

    Summary Despite near stagnation in the euro area and the negative impact of the Ukraine crisis, in most of the NMS economies and some of the Western Balkan countries growth prospects are viewed as positive. While the NMS economies will preserve their positive growth differential vis-à-vis the EU-28, Russia and Ukraine are facing a deterioration of their economic performance. External factors have had a major impact on growth performance in the CESEE region. Financial transfers from the EU hav...

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

    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

  7. The effect of adaptive performance support system on learning achievements of students

    Kommers, Piet; Stoyanov, Slavi; Mileva, Nevena; Martinez Mediano, Catalina

    2008-01-01

    The study compares the effectiveness of two performance support systems, adaptive and non-adaptive, on learning achievements of engineering students. In addition, the research design controls for a possible effect of learning style. The analysis reveals that students working with an adaptive perform

  8. Performance Assessment: Looking at the "Real" Achievement of Middle Level Students.

    Aseltine, James M.

    1993-01-01

    Performance assessment may be the best vehicle for validating student achievement. Performance assessment, in theory and practice, is compatible with middle-school philosophy, stated mission, organizational structure, and instructional models. The challenge is to reexamine program outcomes and decide what middle-level students should know and be…

  9. Boasts are a boost: achievement prime self-reactivity predicts subsequent academic performance.

    Gramzow, Richard H; Johnson, Camille S; Willard, Greg

    2014-03-01

    The present research tests the hypothesis that self-reactivity following an achievement prime reflects the strength of achievement goals and is a predictor of future goal-relevant performance. In Studies 1-3, undergraduates reported their grade-point averages (GPAs) following either an achievement goal prime or a control prime. Academic exaggeration (higher self-reported than official GPA) was the indicator of self-reactivity to the prime. Study 1 involved a direct achievement goal prime, whereas Studies 2 and 3 involved indirect priming techniques. In all 3 experiments, greater academic exaggeration following the achievement goal prime (but not the control prime) predicted better academic performance a semester later (based on official records). Study 4 demonstrated that the magnitude of students' GPA goals mediated the association between academic exaggeration and subsequent performance (1 year later). The fact that self-reactivity to a single achievement goal prime in the lab predicted later performance in "real life" suggests that individual differences in reactivity to a specific prime can signal much broader motivational orientations related to the primed goal. PMID:24588092

  10. Corporate Governance as a Crucial Factor in Achieving Sustainable Corporate Performance

    Julija Bistrova; Natalja Lace; Manuela Tvaronaviciene

    2014-01-01

    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 va...

  11. Stability analysis of stagnation-point flow over a stretching/shrinking sheet

    I. S. Awaludin

    2016-04-01

    Full Text Available The stagnation point flow over a linearly stretching or shrinking sheet is considered in the present study. The transformed ordinary differential equations are solved numerically. Dual solutions are possible for the shrinking case, while the solution is unique for the stretching case. For the shrinking case, a linear temporal stability analysis is performed to determine which one of the solution is stable and thus physically reliable.

  12. Patterns of growth and stagnation in the late nineteenth century Habsburg economy.

    Schulze, Max-Stephan

    2000-01-01

    This article addresses two issues that feature prominently in the recent historiography. First, how does the Habsburg Empire's economic performance compare to the record for other European economies in terms of levels and growth of national income? Second, to what extent was the Austrian economy subject to prolonged stagnation after 1873? These questions are examined on the basis of new annual estimates of GDP for Austria and Hungary for 1870 to 1913. The article argues, first, that over the ...

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

    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

  14. Nuclear power performance and safety. V.2. Achievements in construction and operation

    The International Conference on Nuclear Power Performance and Safety, organized by the International Atomic Energy Agency, was held at the Austria Centre Vienna (ACV) in Vienna, Austria, from 28 September to 2 October 1987. The objective of the Conference was to promote an exchange of worldwide information on the current trends in the performance and safety of nuclear power and its fuel cycle, and to take a forward look at the expectations and objectives for the 1990s. This objective was accomplished through presentation and discussion of about 200 papers at the Conference. This is volume 2 of the Conference proceedings. The presentations in this volume were divided into the following sections: plant construction achievements (8 papers); plant availability achievements (12 papers); controlling and financing nuclear power cost (6 papers); achievements in technology transfer and infrastructure development (5 papers); advanced systems (9 papers). A separate abstract was prepared for each of these papers. Refs, figs and tabs

  15. The Role of General and Performance Self Esteem In Relation Academic Procrastination and Academic Achievement

    Balkıs, Murat; Duru, Erdinç

    2010-01-01

    In this study, mediator role of general and performance self esteem were investigated in relation to the academic procrastination and reported academic achievement. The participants were 323 students who study different major fields at the Faculty of Education in Pamukkale University. Age range varied from 17 to 31. In this study, Aitken Procrastination Inventory, Rosenberg Self Esteem Inventory, Performance Self Esteem Subscale of State Self Esteem Scale and Personal Information Sheet w...

  16. Performance Concern, Contingent Self-Worth, and Responses to Repeated Achievement Failure in Second Graders

    Smiley, Patricia A.; Coulson, Sheri L.; Greene, Joelle K.; Bono, Katherine L.

    2010-01-01

    Individual differences in emotion, cognitions, and task choice following achievement failure are found among four- to seven-year-olds. However, neither performance deterioration during failure nor generalization after failure--aspects of the helpless pattern in 10-year-olds--have been reliably demonstrated in this age group. In the present study,…

  17. Immigrant Children's Educational Achievement in Western Countries: Origin, Destination, and Community Effects on Mathematical Performance

    Levels, Mark; Dronkers, Jaap; Kraaykamp, Gerbert

    2008-01-01

    This article explores the extent to which macro-level characteristics of destination countries, origin countries, and immigrant communities help explain differences in immigrant children's educational achievement. Using data from the 2003 PISA survey, we analyze the mathematical performance of 7,403 pupils from 35 different origin countries in 13…

  18. The effect of adaptive performance support system on learning achievements of students.

    Kommers, Piet; Stoyanov, Slavi; Mileva, Nevena; Martínez Mediano, Catalina

    2008-01-01

    Kommers, P., Stoyanov, S., Mileva, N., & Kommers, P., Stoyanov, S., Mileva, N., & Martínez Mediano, K. (2008). The effect of adaptive performance support system on learning achievements of students. International Journal of Continuing Engineering Education and Lifelong Learning, 18 (3), 351-365

  19. Gender, Geographic Locations, Achievement Goals and Academic Performance of Secondary School Students from Borno State, Nigeria

    Musa, Alice K.J.

    2013-01-01

    The paper examined gender, geography location, achievement goals and academic performance of senior secondary school students in Borno State, Nigeria. The sample consists of 827 students from 18 public boarding secondary schools across South and North of Borno State: 414 (50.1 per cent) males and 413 (49.9 per cent) are females; 414 (50.1 per…

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

    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…

  1. Using Self-Correction to Improve the Spelling Performance of Low-Achieving Third Graders.

    Wirtz, Connie L.; And Others

    1996-01-01

    Comparison of two spelling strategies (traditional versus self-correction) on spelling performance of six low-achieving third-grade students found the self-correction procedure more effective than the traditional condition and also helped students maintain their ability to correctly spell previously learned words. (Author/DB)

  2. Physical activity, cognitive performance, and academic achievement: an observational study in Dutch adolescents using accelerometers

    Van Dijk, Martin; De Groot, Renate; Savelberg, Hans; Van Acker, Frederik; Kirschner, Paul A.

    2013-01-01

    Van Dijk, M. L., De Groot, R. H. M., Savelberg, H. C. M., Van Acker, F. H. M., & Kirschner, P. A. (2013, 7 November). Physical activity, cognitive performance, and academic achievement: an observational study in Dutch adolescents using accelerometers. Paper presentation at ICO National Fall School 2

  3. Physical activity, cognitive performance, and academic achievement: an observational study in Dutch adolescents using accelerometers

    Van Dijk, Martin; De Groot, Renate; Savelberg, Hans; Van Acker, Frederik; Kirschner, Paul A.

    2013-01-01

    Van Dijk, M. L., De Groot, R. H. M., Savelberg, H. C. M., Van Acker, F. H. M., & Kirschner, P. A. (2013, 7 November). Physical activity, cognitive performance, and academic achievement: an observational study in Dutch adolescents using accelerometers. Paper presentation at ICO National Fall School 2013, Maastricht, The Netherlands.

  4. Associations between physical activity, cognitive performance, and academic achievement in Dutch adolescents: The GOALS Study

    Van Dijk, Martin; De Groot, Renate; Savelberg, Hans; Van Acker, Frederik; Kirschner, Paul A.

    2013-01-01

    Van Dijk, M. L., De Groot, R. H. M., Van Acker, F., Savelberg, H. C. M., & Kirschner, P. A. (2013, 12 November). Associations between physical activity, cognitive performance, and academic achievement in Dutch adolescents: The GOALS Study. Presentation at the Learning and Cognition plenary, Heerlen,

  5. Associations between physical activity, cognitive performance, and academic achievement in Dutch adolescents: The GOALS Study

    Van Dijk, Martin; De Groot, Renate; Savelberg, Hans; Van Acker, Frederik; Kirschner, Paul A.

    2013-01-01

    Van Dijk, M. L., De Groot, R. H. M., Van Acker, F., Savelberg, H. C. M., & Kirschner, P. A. (2013, 12 November). Associations between physical activity, cognitive performance, and academic achievement in Dutch adolescents: The GOALS Study. Presentation at the Learning and Cognition plenary, Heerlen, The Netherlands.

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

    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

  7. The Influence of Overt Practice, Achievement Level, and Explanatory Style on Calibration Accuracy and Performance

    Bol, Linda; Hacker, Douglas J.; O'Shea, Patrick; Allen, Dwight

    2005-01-01

    The authors measured the influence of overt calibration practice, achievement level, and explanatory style on calibration accuracy and exam performance. Students (N = 356) were randomly assigned to either an overt practice or no-practice condition. Students in the overt practice condition made predictions and postdictions about their performance…

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

    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.

  9. Response of air stagnation frequency to anthropogenically enhanced radiative forcing

    Stagnant atmospheric conditions can lead to hazardous air quality by allowing ozone and particulate matter to accumulate and persist in the near-surface environment. By changing atmospheric circulation and precipitation patterns, global warming could alter the meteorological factors that regulate air stagnation frequency. We analyze the response of the National Climatic Data Center (NCDC) air stagnation index (ASI) to anthropogenically enhanced radiative forcing using global climate model projections of late-21st century climate change (SRESA1B scenario). Our results indicate that the atmospheric conditions over the highly populated, highly industrialized regions of the eastern United States, Mediterranean Europe, and eastern China are particularly sensitive to global warming, with the occurrence of stagnant conditions projected to increase by 12–25% relative to late-20th century stagnation frequencies (3–18 + days yr−1). Changes in the position/strength of the polar jet, in the occurrence of light surface winds, and in the number of precipitation-free days all contribute to more frequent late-21st century air mass stagnation over these high-population regions. In addition, we find substantial inter-model spread in the simulated response of stagnation conditions over some regions using either native or bias corrected global climate model simulations, suggesting that changes in the atmospheric circulation and/or the distribution of precipitation represent important sources of uncertainty in the response of air quality to global warming. (letter)

  10. Response of air stagnation frequency to anthropogenically enhanced radiative forcing.

    Horton, Daniel E; Harshvardhan; Diffenbaugh, Noah S

    2012-01-01

    Stagnant atmospheric conditions can lead to hazardous air quality by allowing ozone and particulate matter to accumulate and persist in the near-surface environment. By changing atmospheric circulation and precipitation patterns, global warming could alter the meteorological factors that regulate air stagnation frequency. We analyze the response of the National Climatic Data Center (NCDC) Air Stagnation Index (ASI) to anthropogenically enhanced radiative forcing using global climate model projections of late-21(st) century climate change (SRES A1B scenario). Our results indicate that the atmospheric conditions over the highly populated, highly industrialized regions of the eastern United States, Mediterranean Europe, and eastern China are particularly sensitive to global warming, with the occurrence of stagnant conditions projected to increase 12-to-25% relative to late-20(th) century stagnation frequencies (3-18+ days/year). Changes in the position/strength of the polar jet, in the occurrence of light surface winds, and in the number of precipitation-free days all contribute to more frequent late-21(st) century air mass stagnation over these high-population regions. In addition, we find substantial inter-model spread in the simulated response of stagnation conditions over some regions using either native or bias corrected global climate model simulations, suggesting that changes in the atmospheric circulation and/or the distribution of precipitation represent important sources of uncertainty in the response of air quality to global warming. PMID:23284587

  11. A physical education trial improves adolescents' cognitive performance and academic achievement: the EDUFIT study.

    Ardoy, D N; Fernández-Rodríguez, J M; Jiménez-Pavón, D; Castillo, R; Ruiz, J R; Ortega, F B

    2014-02-01

    To analyze the effects of an intervention focused on increasing the time and intensity of Physical Education (PE), on adolescents' cognitive performance and academic achievement. A 4-month group-randomized controlled trial was conducted in 67 adolescents from South-East Spain, 2007. Three classes were randomly allocated into control group (CG), experimental group 1 (EG1) and experimental group 2 (EG2). CG received usual PE (two sessions/week), EG1 received four PE sessions/week and EG2 received four PE sessions/week of high intensity. Cognitive performance (non-verbal and verbal ability, abstract reasoning, spatial ability, verbal reasoning and numerical ability) was assessed by the Spanish Overall and Factorial Intelligence Test, and academic achievement by school grades. All the cognitive performance variables, except verbal reasoning, increased more in EG2 than in CG (all P improved more than EG1, without differences between EG1 and CG. Increased PE can benefit cognitive performance and academic achievement. This study contributes to the current knowledge by suggesting that the intensity of PE sessions might play a role in the positive effect of physical activity on cognition and academic success. Future studies involving larger sample sizes should confirm or contrast these preliminary findings. PMID:23826633

  12. Average Minimum Transmit Power to achieve SINR Targets: Performance Comparison of Various User Selection Algorithms

    Salim, Umer

    2010-01-01

    In multi-user communication from one base station (BS) to multiple users, the problem of minimizing the transmit power to achieve some target guaranteed performance (rates) at users has been well investigated in the literature. Similarly various user selection algorithms have been proposed and analyzed when the BS has to transmit to a subset of the users in the system, mostly for the objective of the sum rate maximization. We study the joint problem of minimizing the transmit power at the BS to achieve specific signal-to-interference-and-noise ratio (SINR) targets at users in conjunction with user scheduling. The general analytical results for the average transmit power required to meet guaranteed performance at the users' side are difficult to obtain even without user selection due to joint optimization required over beamforming vectors and power allocation scalars. We study the transmit power minimization problem with various user selection algorithms, namely semi-orthogonal user selection (SUS), norm-based...

  13. Relationships among multiple intelligences, motor performance and academic achievement in secondary school children

    Ruiz Perez, Luis Miguel; Palomo Nieto, Miriam; Ramon Otero, Irene; Ruiz Amengual, Aixa; Navia Manzano, José Antonio

    2014-01-01

    This study examines the relationships between multiple intelligences, academic achievement and motor performance in a group of secondary school children. Four hundred and eighty schoolchildren participated in this study (171 female and 309 male) with an average age of 13.33 years (SD: 1.41). The Revised self-efficacy Inventory for Multiple Intelligences (IAIM-R) and the motor test Sportcomp were applied, and the average results of the academic year they had made were obtained. The analysis of...

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

    BORAN, Ali İhsan; Kübra AÇIKGÜL; KÖKSAL, Mustafa Serdar

    2015-01-01

    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 achieveme...

  15. Do Achievement Goals Mediate Stereotype Threat? An Investigation on Females' Soccer Performance

    Chalabaev, Aïna; Sarrazin, Philippe; Stone, Jeff; Cury, François

    2008-01-01

    This research investigated stereotype threat effects on women's performance in sports and examined the mediation of this effect by achievement goals. The influence of two stereotypes – relative to the poor athletic ability and the poor technical soccer ability of women – were studied. Fifty-one female soccer players were randomly assigned to one of three conditions, introducing the task as diagnostic of athletic ability, technical soccer ability, or sports psychology. Next, they filled out a ...

  16. AN ENERGY MODEL FOR ACHIEVING HIGH PERFORMANCE BURST TRANSMISSION IN OBCS NETWORKS

    Renuka, R.; Kavitha, V.

    2013-01-01

    Optical burst switching is a promising solution for all optical WDM networks. It combines the benefits of optical circuit switching and optical packet switching. In OBS, the user data is collected at the edge of the network, sorted based on the destination address and grouped into variable size bursts. The OBS framework has been widely used in past years, for recent work use Optical Burst Chain switching (OBCS) to achieve high performance. Here switching unit is burst chain it consist of non-...

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

    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.

  18. AN ENERGY MODEL FOR ACHIEVING HIGH PERFORMANCE BURST TRANSMISSION IN OBCS NETWORKS

    R.RENUKA

    2013-04-01

    Full Text Available Optical burst switching is a promising solution for all optical WDM networks. It combines the benefits of optical circuit switching and optical packet switching. In OBS, the user data is collected at the edge of the network, sorted based on the destination address and grouped into variable size bursts. The OBS framework has been widely used in past years, for recent work use Optical Burst Chain switching (OBCS to achieve high performance. Here switching unit is burst chain it consist of non-periodic bursts in one wavelength. We present extensive simulation result for throughput, delay and energy to demonstrate its superior performance over OBS networks.

  19. Achieving High Performance Distributed System: Using Grid, Cluster and Cloud Computing

    Sunil Kr Singh

    2015-02-01

    Full Text Available To increase the efficiency of any task, we require a system that would provide high performance along with flexibilities and cost efficiencies for user. Distributed computing, as we are all aware, has become very popular over the past decade. Distributed computing has three major types, namely, cluster, grid and cloud. In order to develop a high performance distributed system, we need to utilize all the above mentioned three types of computing. In this paper, we shall first have an introduction of all the three types of distributed computing. Subsequently examining them we shall explore trends in computing and green sustainable computing to enhance the performance of a distributed system. Finally presenting the future scope, we conclude the paper suggesting a path to achieve a Green high performance distributed system using cluster, grid and cloud computing

  20. Stability of stagnation via an expanding accretion shock wave

    Velikovich, A L; Taylor, B D; Giuliani, J L; Zalesak, S T; Iwamoto, Y

    2016-01-01

    Stagnation of a cold plasma streaming to the center or axis of symmetry via an expanding accretion shock wave is ubiquitous in inertial confinement fusion (ICF) and high-energy-density plasma physics, the examples ranging from plasma flows in x-ray-generating Z pinches [Y. Maron et al., Phys. Rev. Lett. 111, 035001 (2013)] to the experiments in support of the recently suggested concept of impact ignition in ICF [H. Azechi et al., Phys. Rev. Lett. 102, 235002 (2009); M. Murakami et al., Nucl. Fusion 54, 054007 (2014)]. Some experimental evidence indicates that stagnation via an expanding shock wave is stable, but its stability has never been studied theoretically. We present such analysis for the stagnation that does not involve a rarefaction wave behind the expanding shock front and is described by the classic ideal-gas Noh solution in spherical and cylindrical geometry. In either case the stagnated flow has been demonstrated to be stable, initial perturbations exhibiting a power-law, oscillatory or monotonic...

  1. Stability of stagnation via an expanding accretion shock wave

    Velikovich, A. L.; Murakami, M.; Taylor, B. D.; Giuliani, J. L.; Zalesak, S. T.; Iwamoto, Y.

    2016-05-01

    Stagnation of a cold plasma streaming to the center or axis of symmetry via an expanding accretion shock wave is ubiquitous in inertial confinement fusion (ICF) and high-energy-density plasma physics, the examples ranging from plasma flows in x-ray-generating Z pinches [Maron et al., Phys. Rev. Lett. 111, 035001 (2013)] to the experiments in support of the recently suggested concept of impact ignition in ICF [Azechi et al., Phys. Rev. Lett. 102, 235002 (2009); Murakami et al., Nucl. Fusion 54, 054007 (2014)]. Some experimental evidence indicates that stagnation via an expanding shock wave is stable, but its stability has never been studied theoretically. We present such analysis for the stagnation that does not involve a rarefaction wave behind the expanding shock front and is described by the classic ideal-gas Noh solution in spherical and cylindrical geometry. In either case, the stagnated flow has been demonstrated to be stable, initial perturbations exhibiting a power-law, oscillatory or monotonic, decay with time for all the eigenmodes. This conclusion has been supported by our simulations done both on a Cartesian grid and on a curvilinear grid in spherical coordinates. Dispersion equation determining the eigenvalues of the problem and explicit formulas for the eigenfunction profiles corresponding to these eigenvalues are presented, making it possible to use the theory for hydrocode verification in two and three dimensions.

  2. Estimation of Centers and Stagnation points in optical flow fields

    Larsen, Rasmus

    1997-01-01

    allows us to give a qualitative local description of the flow field and to estimate the position of stagnation points (e.g. nodes, saddles, and centers). We will apply the algorithm to two data sets. The first sequence consists of infrared images from the meteorological satellite Meteosat. Here the...

  3. Theoretical study on a solar collector loop during stagnation

    Chen, Ziqian; Dragsted, Janne; Furbo, Simon;

    2010-01-01

    collector loop, the mass of the fluid flowing into the pressurized expansion vessel and the pressures at the top part and at the bottom part of the solar collector loop during stagnation for the solar collector loop are calculated. The theoretically calculated results are compared with experimental results...

  4. Theoretical study on a solar collector loop during stagnation

    Chen, Ziqian; Dragsted, Janne; Furbo, Simon;

    collector loop, the mass of the fluid flowing into the pressurized expansion vessel and the pressures at the top part and at the bottom part of the solar collector loop during stagnation for the solar collector loop are calculated. The theoretically calculated results are compared with experimental results...

  5. THE IMPACT OF EMPLOYEE EMPOWERMENT ON ACHIEVEMENT MOTIVATION AND CONTEXTUAL PERFORMANCE OF EMPLOYEE: A CASE BANKING SECTOR IN PAKISTAN

    Mudassar Ghafoor; Sadaf Amjad Gillani; Maria Zafar Cheema; M. Azeem

    2013-01-01

    The rationale of study is to investigate the effects of employee empowerment on achievement motivation and contextual performance of employees. Responses of employees in Public and private banks have been analyzed by using regressions analysis. The results of study show the positive impact of employee empowerment of achievement motivation and contextual performance of employees. It implies that employee empowerment is important for achievement motivation and ultimate performance for employees...

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

    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

  7. Achieving High Performance in AC-Field Driven Organic Light Sources

    Xu, Junwei; Carroll, David L.; Smith, Gregory M.; Dun, Chaochao; Cui, Yue

    2016-04-01

    Charge balance in organic light emitting structures is essential to simultaneously achieving high brightness and high efficiency. In DC-driven organic light emitting devices (OLEDs), this is relatively straight forward. However, in the newly emerging, capacitive, field-activated AC-driven organic devices, charge balance can be a challenge. In this work we introduce the concept of gating the compensation charge in AC-driven organic devices and demonstrate that this can result in exceptional increases in device performance. To do this we replace the insulator layer in a typical field-activated organic light emitting device with a nanostructured, wide band gap semiconductor layer. This layer acts as a gate between the emitter layer and the voltage contact. Time resolved device characterization shows that, at high-frequencies (over 40 kHz), the semiconductor layer allows for charge accumulation in the forward bias, light generating part of the AC cycle and charge compensation in the negative, quiescent part of the AC cycle. Such gated AC organic devices can achieve a non-output coupled luminance of 25,900 cd/m2 with power efficiencies that exceed both the insulator-based AC devices and OLEDs using the same emitters. This work clearly demonstrates that by realizing balanced management of charge, AC-driven organic light emitting devices may well be able to rival today’s OLEDs in performance.

  8. Corporate Governance as a Crucial Factor in Achieving Sustainable Corporate Performance

    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.

  9. High-Achieving High School Students and Not so High-Achieving College Students: A Look at Lack of Self-Control, Academic Ability, and Performance in College

    Honken, Nora B.; Ralston, Patricia A. S.

    2013-01-01

    This study investigated the relationship among lack of self-control, academic ability, and academic performance for a cohort of freshman engineering students who were, with a few exceptions, extremely high achievers in high school. Structural equation modeling analysis led to the conclusion that lack of self-control in high school, as measured by…

  10. Achieving realistic performance and decison-making capabilities in computer-generated air forces

    Banks, Sheila B.; Stytz, Martin R.; Santos, Eugene, Jr.; Zurita, Vincent B.; Benslay, James L., Jr.

    1997-07-01

    For a computer-generated force (CGF) system to be useful in training environments, it must be able to operate at multiple skill levels, exhibit competency at assigned missions, and comply with current doctrine. Because of the rapid rate of change in distributed interactive simulation (DIS) and the expanding set of performance objectives for any computer- generated force, the system must also be modifiable at reasonable cost and incorporate mechanisms for learning. Therefore, CGF applications must have adaptable decision mechanisms and behaviors and perform automated incorporation of past reasoning and experience into its decision process. The CGF must also possess multiple skill levels for classes of entities, gracefully degrade its reasoning capability in response to system stress, possess an expandable modular knowledge structure, and perform adaptive mission planning. Furthermore, correctly performing individual entity behaviors is not sufficient. Issues related to complex inter-entity behavioral interactions, such as the need to maintain formation and share information, must also be considered. The CGF must also be able to acceptably respond to unforeseen circumstances and be able to make decisions in spite of uncertain information. Because of the need for increased complexity in the virtual battlespace, the CGF should exhibit complex, realistic behavior patterns within the battlespace. To achieve these necessary capabilities, an extensible software architecture, an expandable knowledge base, and an adaptable decision making mechanism are required. Our lab has addressed these issues in detail. The resulting DIS-compliant system is called the automated wingman (AW). The AW is based on fuzzy logic, the common object database (CODB) software architecture, and a hierarchical knowledge structure. We describe the techniques we used to enable us to make progress toward a CGF entity that satisfies the requirements presented above. We present our design and

  11. Improvement in performance of DM plant, secondary systems for achieving chemistry performance indicator of KGS-3 and 4

    Kaiga Generating Station (KGS)-3 and 4 has two 220 MWe Pressurized Heavy Water Reactors. It uses Heavy water as moderator and coolant and DM (De-mineralized) water in secondary system for steam generation. Raw water for plant is taken from Kali River. Raw water is first treated in pretreatment plant and Dual media filter for turbidity removal. Chlorination is carried out for control of micro-organism. DM water is makeup to feed water which is the input to Steam Generator for production of steam for power generation. Continuous blow down through Boiler blow down (BBD) IX column is carried out to control Steam Generator (SG) chemistry. It was decided by Nuclear Power Corporation India Limited (NPCIL) management to calculate Chemistry Performance Indicator of KGS secondary system and it was found 2.6 which was much higher than Standard and best achievable value of 1.0. Detailed analysis was carried out and improvements required in DM plant, water treatment plant, BBD IX column, Steam Generator etc were identified and plan was made for improvement. Turbidity of filter water was brought below 2.0 NTU. Many changes were incorporated in DM plant. Regenerate concentration, regeneration levels and regeneration procedures were modified. Resin replacement frequencies were fixed and brine treatment of anion resin was started at regular interval. For DM water production two mixed resin columns in series were used in place of earlier one mixed resin column. By these modifications DM water Chloride, Sodium and Sulphate were brought <1.0 ppb from earlier 5-10 ppb. Regeneration procedure of BBD IX column were standardized. Service life of BBD IX column was fixed and was isolated from service before exhaustion. Design deficiencies of BBD IX column was rectified by applying innovative idea. Online sodium analyzer was installed in boiler blow down line. By implementing these improvements Chemistry Performance Indicator of both units were brought down to 1.0, which is standard and best

  12. Magnetohydrodynamic stagnation point flow with a convective surface boundary condition

    Jafar, Khamisah [Universiti Kebangsaan Malaysia, Bangi, Selangor (Malaysia). Faculty of Engineering and Built Environment; Ishak, Anuar; Nazar, Roslinda [Universiti Kebangsaan, Bangi, Selangor (Malaysia). School of Mathematical Sciences

    2011-08-15

    This study analyzes the steady laminar two-dimensional stagnation point flow and heat transfer of an incompressible viscous fluid impinging normal to a horizontal plate, with the bottom surface of the plate heated by convection from a hot fluid. A uniform magnetic field is applied in a direction normal to the flat plate, with a free stream velocity varying linearly with the distance from the stagnation point. The governing partial differential equations are first transformed into ordinary differential equations, before being solved numerically. The analysis includes the effects of the magnetic parameter, the Prandtl number, and the convective parameter on the heat transfer rate at the surface. Results showed that the heat transfer rate at the surface increases with increasing values of these quantities. (orig.)

  13. Spectroscopic study of z-pinch stagnation on Z.

    Maron, Yitzhak (Weizmann Institute of Science); Weingarten, L. (Weizmann Institute of Science); Starobinets, A. (Weizmann Institute of Science); Fisher, V. (Weizmann Institute of Science); Jennings, Christopher A.; Ampleford, David J.; Bailey, James E.; Yu, Edmund P.; Bernshtam, V. (Weizmann Institute of Science); Cuneo, Michael Edward; Rochau, Gregory Alan; Coverdale, Christine Anne; Jones, Brent Manley; Hansen, Stephanie B.

    2010-11-01

    Fast z-pinches provide intense 1-10 keV photon energy radiation sources. Here, we analyze time-, space-, and spectrally-resolved {approx}2 keV K-shell emissions from Al (5% Mg) wire array implosions on Sandia's Z machine pulsed power driver. The stagnating plasma is modeled as three separate radial zones, and collisional-radiative modeling with radiation transport calculations are used to constrain the temperatures and densities in these regions, accounting for K-shell line opacity and Doppler effects. We discuss plasma conditions and dynamics at the onset of stagnation, and compare inferences from the atomic modeling to three-dimensional magneto-hydrodynamic simulations.

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

    Lou, C.; Player, M.A. [Department of Engineering, University of Aberdeen, Aberdeen (United Kingdom)

    2002-07-21

    This paper presents an advection-diffusion model to describe the stagnation of normal grain growth in thin films. The underlying advection-diffusion model describes grain growth in a two-dimensional topological-class/size space. Grain boundary grooving and the correlation between neighbouring grains are introduced into the model to represent stagnation. Grain boundary grooving causes the stagnation of grain growth, and the correlation between neighbouring grains accelerates the effects of stagnation. Numerical solution of continuity equations gives a grain size distribution that is close to log-normal, and fits experiments well. The time development of average grain size also shows the stagnation of grain growth. (author)

  15. Will Europe Fall into a Japanese-Style Stagnation Trap?

    Peter Harrold

    2012-01-01

    Can Europe avoid falling in to a Japanese-style stagnation trap? In this type of trap, we see a repeated cycle of a financial crisis leading to a fiscal crisis, leading to a decline in consumer and investor confidence, and a resulting fall in demand. The decline in growth that inevitably follows simply causes the cycle to repeat itself. In theory, this should lead to improved competitiveness, but in Japan the forces of decline outweighed any boost in export demand.

  16. Previous financial crises leading to stagnation: Selected case studies

    Dodig, Nina; Herr, Hansjörg

    2014-01-01

    This paper analyses several severe financial crises observed in the history of capitalism which led to a longer period of stagnation or low growth. Comparative case studies of the Great Depression, the Latin American debt crisis of the 1980s and the Japanese crisis of the 1990s and 2000s are presented. The following questions are asked: What triggered big financial crises? Which factors intensified financial crises? And most importantly, which factors prevented the return of prosperity for a ...

  17. Wage Stagnation? Fact Disclosure and Cross-Country Comparison

    Chang-Ching Lin; Juin-Jen Chang; Shu-Shiuan Lu

    2014-01-01

    This paper sheds light on three important issues in the macroeconomics literature, which comes to a better understanding of Taiwan’s wage stagnation. First, we explore the trend of labor income shares, namely the labor income-output ratios, in Taiwan. This enables us to understand the distribution or tradeoff between labor and capital shares. Second, we calculate the correlation coefficients between real wages and gross domestic product (GDP) per capita, showing that whether Taiwan’s real wag...

  18. Dynamics and Stagnation in the Malthusian Epoch: Theory and Evidence

    Ashraf, Quamrul; Galor, Oded

    2008-01-01

    This paper empirically tests the predictions of the Malthusian theory with respect to both population dynamics and income per capita stagnation in the pre-Industrial Revolution era. The theory suggests that improvements in technology during this period generated only temporary gains in income per capita, eventually leading to a larger but not richer population. Using exogenous cross-country variations in land productivity and the timing of the Neolithic Revolution, the analysis demonstrates t...

  19. The Long Italian Stagnation and the Welfare Effects of Outsourcing

    Zotti, Jacopo

    2015-01-01

    The stagnation of the Italian economy over the last two decades is widely documented. During this period, the world economy has become highly integrated, and foreign outsourcing has become a standard practice for firms. While trade theory predicts benefits from the internationalization of production, Italy seems to have gained negligibly from it, or, rather to have lost. In a simple model, we show that this may be the case when markets are overregulated and competition policies are weak. We s...

  20. Dynamics and Stagnation in the Malthusain Epoch: Theory and Evidence

    Quamrul Ashraf; Oded Galor

    2008-01-01

    This paper empirically tests the predictions of the Malthusian theory with respect to both population dynamics and income per capita stagnation in the pre-Industrial Revolution era. The theory suggests that improvements in technology during this period generated only temporary gains in income per capita, eventually leading to a larger but not richer population. Using exogenous cross-country variations in land productivity and the timing of the Neolithic Revolution, the analysis demonstrates t...

  1. Acceleration, Stagnation and Crisis: the Role of Policies and Institutions

    Jerzmanowski, Michal

    2011-01-01

    In this paper we study long run economic growth as a sequence of accelerations, slowdowns and crises, and estimate the role of institutions and macroeconomic policies in determining this sequence. We analyze the joint effect of policies and institutions on the frequency of the four growth regimes: stable growth, stagnation, crisis and miracle-like fast growth. The results confirm the importance of institutions for growth but also show that macro-policies; inflation, trade openness, size of go...

  2. Amplification of Vorticity Near the Stagnation Point of Landing Gear Wheels

    Feltham, Graham; Ekmekci, Alis

    2013-11-01

    In this experimental investigation, a stream of steady weak vorticity impinging near the stagnation point of a landing gear wheel is shown to grow and amplify into large-scale vortices that coherently shed from the point of generation. To produce the upstream vorticity, a platinum wire of 100 micron diameter, similar to that used in hydrogen bubble visualization technique, is placed upstream of the wheel model. Experiments are conducted in a recirculating water channel. The wheel diameter is D = 152 mm. The Reynolds number based on the wire diameter is 21 and based on the wheel diameter is 32,500. Qualitative understanding of the vorticity amplification and eventual vortex shedding near the stagnation region of the wheel is achieved by employing the hydrogen bubble visualization technique while quantitative insight is collected using Particle Image Velocimetry (PIV). The size and frequency of the shed vortices are found to depend on the wheel geometry as well as the magnitude and impingement point of the inbound vorticity.

  3. A Novel Hybrid MCDM Procedure for Achieving Aspired Earned Value Project Performance

    Shou-Yan Chou

    2016-01-01

    Full Text Available A better-performing project gains more subsequent businesses. Many organizations worldwide apply an earned value management (EVM system to monitor and control their projects’ performance. However, a successful EVM application requires handling multiple interinfluenced criteria with feedback effects for decision-making and continuous improvements throughout the application life cycle. The conventional decision approaches assume that preferences between criteria are independent and put their focuses on decision-making. This study employs a hybrid multiple criteria decision-making (HMCDM method to devise a novel procedure to fulfil the deficiencies. The proposed procedure enables us to evaluate interinfluence effects and gap indices among criteria/dimensions/alternatives and then systemize the evaluation results in a context of influential network relation map (INRM. The INRM provides managers with visual information to find a route in making application decisions, while identifying critical gaps for continuous improvements. A numerical example is presented to illustrate the applicability of the proposed procedure. The results show that, by employing the HMCDM method, the proposed procedure can provide organizations with a foundation to ensure that the aspired EVM application outcomes are achieved at different levels within an organization.

  4. Effective versus ion thermal temperatures in the Weizmann Ne Z-pinch: Modeling and stagnation physics

    The difference between the ion thermal and effective temperatures is investigated through simulations of the Ne gas puff z-pinch reported by Kroupp et al. [Phys. Rev. Lett. 107, 105001 (2011)]. Calculations are performed using a 2D, radiation-magnetohydrodynamic code with Tabular Collisional-Radiative Equilibrium, namely Mach2-TCRE [Thornhill et al., Phys. Plasmas 8, 3480 (2001)]. The extensive data set of imaging and K-shell spectroscopy from the experiments provides a challenging validation test for z-pinch simulations. Synthetic visible images of the implosion phase match the observed large scale structure if the breakdown occurs at the density corresponding to the Paschen minimum. At the beginning of stagnation (−4 ns), computed plasma conditions change rapidly showing a rising electron density and a peak in the ion thermal temperature of ∼1.8 keV. This is larger than the ion thermal temperature (<400 eV) inferred from the experiment. By the time of peak K-shell power (0 ns), the calculated electron density is similar to the data and the electron and ion thermal temperatures are equilibrated, as is observed. Effective ion temperatures are obtained from calculated emission line widths accounting for thermal broadening and Doppler velocity shifts. The observed, large effective ion temperatures (∼4 keV) early in the stagnation of this Ne pinch can be explained solely as a combination of compressional ion heating and steep radial velocity gradients near the axis. Approximations in the modeling are discussed in regard to the higher ion thermal temperature and lower electron density early in the stagnation compared to the experimental results

  5. Effective versus ion thermal temperatures in the Weizmann Ne Z-pinch: Modeling and stagnation physics

    Giuliani, J. L.; Thornhill, J. W.; Kroupp, E.; Osin, D.; Maron, Y.; Dasgupta, A.; Apruzese, J. P.; Velikovich, A. L.; Chong, Y. K.; Starobinets, A.; Fisher, V.; Zarnitsky, Yu.; Bernshtam, V.; Fisher, A.; Mehlhorn, T. A.; Deeney, C.

    2014-03-01

    The difference between the ion thermal and effective temperatures is investigated through simulations of the Ne gas puff z-pinch reported by Kroupp et al. [Phys. Rev. Lett. 107, 105001 (2011)]. Calculations are performed using a 2D, radiation-magnetohydrodynamic code with Tabular Collisional-Radiative Equilibrium, namely Mach2-TCRE [Thornhill et al., Phys. Plasmas 8, 3480 (2001)]. The extensive data set of imaging and K-shell spectroscopy from the experiments provides a challenging validation test for z-pinch simulations. Synthetic visible images of the implosion phase match the observed large scale structure if the breakdown occurs at the density corresponding to the Paschen minimum. At the beginning of stagnation (-4 ns), computed plasma conditions change rapidly showing a rising electron density and a peak in the ion thermal temperature of ˜1.8 keV. This is larger than the ion thermal temperature (<400 eV) inferred from the experiment. By the time of peak K-shell power (0 ns), the calculated electron density is similar to the data and the electron and ion thermal temperatures are equilibrated, as is observed. Effective ion temperatures are obtained from calculated emission line widths accounting for thermal broadening and Doppler velocity shifts. The observed, large effective ion temperatures (˜4 keV) early in the stagnation of this Ne pinch can be explained solely as a combination of compressional ion heating and steep radial velocity gradients near the axis. Approximations in the modeling are discussed in regard to the higher ion thermal temperature and lower electron density early in the stagnation compared to the experimental results.

  6. Achieving numerical accuracy and high performance using recursive tile LU factorization with partial pivoting

    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

  7. Measuring Metacognition and Reaction Time: Further Findings on the Performances of General Education, Low-Achieving, and Institutionally Raised Students

    Al-Hilawani, Yasser A.; Abdullah, Ahmad A.

    2010-01-01

    The purpose of this study was to use the picture format to examine in depth the metacognitive performances and reaction time in general education, low-achieving, and institutionally raised students. Results revealed that institutionally raised students, unlike low-achieving students, took significantly the longest reaction time to finish the test…

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

    James, Conrad D.; Schiess, Adrian B.; Howell, Jamie; Baca, Micheal J.; Partridge, L. Donald [University of New Mexico, Albuquerque, NM; 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%5E16 operations/s. Current supercomputer technology has reached 1015 operations/s, yet it requires 1500m%5E3 and 3MW, giving the brain a 10%5E12 advantage in operations/s/W/cm%5E3. 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.

  9. Circuit modeling and component trimming to achieve performance requirements for the DARHT prototype injector

    To produce an acceptable electron beam, the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility accelerators require high-voltage pulses that are flat to within ±1% for 65±ns. Achieving this accuracy and pulse duration in operation on the Integrated Test Stand (a full-scale prototype of the DARHT 4-Mev injector and first eight linear induction accelerator cells) has required fine-tuning selected components in the injector pulsed power circuits. Several circuit analysis codes are used to analyze circuit performance and to predict the effects of component changes. Four cases are presented. (1) The center conductor of an ethylene glycol transmission line was tapered to compensate for a 4-5% tilt of the flat-top portion cf the injector voltage waveform. (2) The mixture of water-glycol solution used in the Blumlein ''peaking'' section was changed to compensate for a 2% hump in the flat-top portion of the voltage waveform. (3) Confirmation was provided that observed changes in pulse shape could be caused by changes in dielectric constant of the ethylene glycol used in the Blumlein, caused by hygroscopic absorption of water vapor. (4) A damping resistor was added in series with the Blumlein center conductor to reduce the amplitude of low-frequency, post-pulse oscillations that were causing late-time flash-overs of the vacuum insulator

  10. Performance of Learning Disabled and Low Achieving Secondary Students on Formal Features of a Paragraph-Writing Task.

    Moran, Mary Ross

    1981-01-01

    Writing samples were analyzed for syntactic maturity, productivity and word selection; for conventions such as tense and number markers and number agreement; and for spelling, punctuation, and capitalization. Only spelling performance proved significantly different in favor of low achievers. (Author)

  11. Physical Activity Before School, Cognitive Performance, and Academic Achievement in Dutch Adolescents: Let them Walk or Cycle to School!

    Van Dijk, Martin; De Groot, Renate; Van Acker, Frederik; Savelberg, Hans; Kirschner, Paul A.

    2014-01-01

    In this study, associations between objectively measured active commuting to school and cognitive performance and academic achievement in Dutch adolescents were investigated. Active commuting to school was found to be positively associated with executive functioning in adolescent girls.

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

    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

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

    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. PMID:24130084

  14. How Do Relationships Influence Student Achievement? Understanding Student Performance from a General, Social Psychological Standpoint

    Aspelin, Jonas

    2012-01-01

    This article explores the influence of relationships on student achievement by examining empirical evidence and by adopting a social psychological theory. Initially, the issue is addressed from a national, Swedish context. Thereafter, two general questions are raised: (1) What is the influence of relationships on student achievement, according to…

  15. Performance-Based Music Ensembles' Effects on Academic Achievement: A Correlational Study

    Stevenson, Timothy Francis

    2013-01-01

    As increasing student achievement levels for all learners continues to drive the focus of education, identifying strategies and opportunities to accomplish this goal becomes progressively more important. This study explored the concepts of self-efficacy, self-efficacy for self-regulated learning, and self-efficacy for academic achievement in…

  16. Tracking Student Achievement in Music Performance: Developing Student Learning Objectives for Growth Model Assessments

    Wesolowski, Brian C.

    2015-01-01

    Student achievement growth data are increasingly used for assessing teacher effectiveness and tracking student achievement in the classroom. Guided by the student learning objective (SLO) framework, music teachers are now responsible for collecting, tracking, and reporting student growth data. Often, the reported data do not accurately reflect the…

  17. Cohort versus Non-Cohort High School Students' Math Performance: Achievement Test Scores and Coursework

    Parke, Carol S.; Keener, Dana

    2011-01-01

    The purpose of this study is to compare multiple measures of mathematics achievement for 1,378 cohort students who attended the same high school in a district from 9th to 12th grade with non-cohort students in each grade level. Results show that mobility had an impact on math achievement. After accounting for gender, ethnicity, and SES, adjusted…

  18. Achievement First: Developing a Teacher Performance Management System That Recognizes Excellence

    Curtis, Rachel

    2011-01-01

    Teachers are the single most important school-related factor in students' learning, and improving student learning is the single most important goal at Achievement First (AF), a fast-growing public charter school network in the Northeast. To achieve this goal, the AF team has worked to establish a common understanding of effective instructional…

  19. Avoiding Intellectual Stagnation: The Starship as an Expander of Minds

    Crawford, Ian A

    2015-01-01

    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".

  20. Pressure and temperature development in solar heating system during stagnation

    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......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...

  1. Stagnation Region Heat Transfer Augmentation at Very High Turbulence Levels

    Ames, Forrest [University of North Dakota; Kingery, Joseph E. [University of North Dakota

    2015-06-17

    A database for stagnation region heat transfer has been extended to include heat transfer measurements acquired downstream from a new high intensity turbulence generator. This work was motivated by gas turbine industry heat transfer designers who deal with heat transfer environments with increasing Reynolds numbers and very high turbulence levels. The new mock aero-combustor turbulence generator produces turbulence levels which average 17.4%, which is 37% higher than the older turbulence generator. The increased level of turbulence is caused by the reduced contraction ratio from the liner to the exit. Heat transfer measurements were acquired on two large cylindrical leading edge test surfaces having a four to one range in leading edge diameter (40.64 cm and 10.16 cm). Gandvarapu and Ames [1] previously acquired heat transfer measurements for six turbulence conditions including three grid conditions, two lower turbulence aero-combustor conditions, and a low turbulence condition. The data are documented and tabulated for an eight to one range in Reynolds numbers for each test surface with Reynolds numbers ranging from 62,500 to 500,000 for the large leading edge and 15,625 to 125,000 for the smaller leading edge. The data show augmentation levels of up to 136% in the stagnation region for the large leading edge. This heat transfer rate is an increase over the previous aero-combustor turbulence generator which had augmentation levels up to 110%. Note, the rate of increase in heat transfer augmentation decreases for the large cylindrical leading edge inferring only a limited level of turbulence intensification in the stagnation region. The smaller cylindrical leading edge shows more consistency with earlier stagnation region heat transfer results correlated on the TRL (Turbulence, Reynolds number, Length scale) parameter. The downstream regions of both test surfaces continue to accelerate the flow but at a much lower rate than the leading edge. Bypass transition occurs

  2. Stagnation and interpenetration of laser-created colliding plasmas

    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.

  3. Stagnation of electron flow by a nonlinearly generated whistler wave

    Taguchi, Toshihiro; Mima, Kunioki

    2016-01-01

    Relativistic electron beam transport through a high-density, magnetized plasma is studied numerically and theoretically. An electron beam injected into a cold plasma excites Weibel and two-stream instabilities that heat the beam and saturate. In the absence of an applied magnetic field, the heated beam continues to propagate. However, when a magnetic field of particular strength is applied along the direction of beam propagation, a secondary instability of off-angle whistler modes is excited. These modes then couple nonlinearly creating a large amplitude parallel propagating whistler that stops the beam. In this letter, we will show the phenomena in detail and explain the mechanism of whistler mediated beam stagnation.

  4. Injection-induced turbulence in stagnation-point boundary layers

    Park, C.

    1984-02-01

    A theory is developed for the stagnation point boundary layer with injection under the hypothesis that turbulence is produced at the wall by injection. From the existing experimental heat transfer rate data obtained in wind tunnels, the wall mixing length is deduced to be a product of a time constant and an injection velocity. The theory reproduces the observed increase in heat transfer rates at high injection rates. For graphite and carbon-carbon composite, the time constant is determined to be 0.0002 sec from the existing ablation data taken in an arc-jet tunnel and a balistic range.

  5. Dye visualization near a three-dimensional stagnation point: application to the vortex breakdown bubble

    Brøns, Morten; Thompson, M. C.; Hourigan, K.

    2009-01-01

    consequently its open nature, can be explained by the very small imperfections that are present in any experimental rig. Distinct from this, here it is shown that even for a perfectly axisymmetric flow and breakdown bubble, the combined effect of dye diffusion and the inevitable small errors in the dye......An analytical model, based on the Fokker-Planck equation, is constructed of the dye visualization expected near a three-dimensional stagnation point in a swirling fluid flow. The model is found to predict dye traces that oscillate in density and position in the meridional plane in which swirling...... the rig. Thus, when interpreting dye-visualization patterns in steady flow, even if axisymmetric flow can be achieved, it is important to take into account the relative diffusivity of the dye and the accuracy of its injection....

  6. From semi-stagnation to growth in a sino-centric market

    Antonio Barros de Castro

    2008-03-01

    Full Text Available According to recent available information, the Brazilian economy may be entering a cycle of sustained growth. The dominant current interpretation points to the progresses made in terms of monetary stability, Balance of Payments and structural reforms. Indeed, without monetary stability and the commercial opening of the economy, investments would not be increasing and credit growth would not be helping the emergence of millions of new consumers. But these achievements should be taken as generally conditioning, rather than actually shaping the new picture. Some unexpected (not rarely positive consequences of overcoming the long enduring semi-stagnation, the emergence of China as a major player, and its consequences on the necessary re-structuring of the Brazilian industry, seem to be decisive in the present day redefinition of the Brazilian GDP growth potential.

  7. Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure

    American Society for Testing and Materials. Philadelphia

    2005-01-01

    1.1 This test method covers the calculation from heat transfer theory of the stagnation enthalpy from experimental measurements of the stagnation-point heat transfer and stagnation pressure. 1.2 Advantages 1.2.1 A value of stagnation enthalpy can be obtained at the location in the stream where the model is tested. This value gives a consistent set of data, along with heat transfer and stagnation pressure, for ablation computations. 1.2.2 This computation of stagnation enthalpy does not require the measurement of any arc heater parameters. 1.3 Limitations and ConsiderationsThere are many factors that may contribute to an error using this type of approach to calculate stagnation enthalpy, including: 1.3.1 TurbulenceThe turbulence generated by adding energy to the stream may cause deviation from the laminar equilibrium heat transfer theory. 1.3.2 Equilibrium, Nonequilibrium, or Frozen State of GasThe reaction rates and expansions may be such that the gas is far from thermodynamic equilibrium. 1.3.3 Noncat...

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

    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…

  9. Achievable Performance and Effective Interrogator Design for SAW RFID Sensor Tags

    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.

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

    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.

  11. Governments that Achieve Results : Introducing Performance Mechanisms and Exploring the Trust Dimension

    Felcman, Daniela

    2010-01-01

    Over the past few decades, a significant number of advanced countries and, more recently, some developing countries have moved the focus of their budget arrangements to emphasize performance. The recently published book results, performance budgeting and trust in Government follows from a conference on performance budgeting held in Mexico in June 2008 where a large range of experiences fro...

  12. The effect of social trust on achievement test performance of students in Japan

    YAMAMURA, Eiji

    2010-01-01

    Empirical results using Japanese data suggest that social trust improves student language and mathematics achievement test scores in primary and junior high school. After controlling for endogeneity bias, social trust had a greater effect on scores for primary school students than on scores for junior high school students.

  13. Performance Evaluation of Methods for Estimating Achievable Throughput on Cellular Connections

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

    2015-01-01

    achievable throughput (AT) is the main focus of this paper, which can be expressed as the data rate that users experience. We establish the Bulk Transfer Capacity (BTC) method as the ground truth of the AT. We choose to evaluate the Trains of Packet-Pair (TOPP) method as an alternative to BTC in estimating...

  14. Standard Errors of Proportions Used in Reporting Changes in School Performance with Achievement Levels.

    Arce-Ferrer, Alvaro; Frisbie, David A.; Kolen, Michael J.

    2002-01-01

    Studies of the achievement test results for about 490 school districts at grade 4 and about 420 districts at grade 5 show that the error variance of estimates of change at the school level is large enough to interfere with interpretations of annual change estimates. (SLD)

  15. Do Children in Montessori Schools Perform Better in the Achievement Test? A Taiwanese Perspective

    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.…

  16. Differentiating Low Performance of the Gifted Learner: Achieving, Underachieving, and Selective Consuming Students

    Figg, Stephanie D.; Rogers, Karen B.; McCormick, John; Low, Renae

    2012-01-01

    The study aimed to empirically verify findings from qualitative studies that showed selective consumers could be distinguished from underachievers with regard to academic self-perception and thinking style preference. Participants, gifted males from an independent secondary boys' school in Sydney, Australia, were categorized as achieving,…

  17. The Relationship between Victimization at School and Achievement: The Cusp Catastrophe Model for Reading Performance

    Sideridis, Georgios D.; Antoniou, Faye; Stamovlasis, Dimitrios; Morgan, Paul L.

    2013-01-01

    We evaluated the relationship between victimization and academic achievement from a nonlinear perspective using a cusp catastrophe model. Participants were 62 students with identified learning disabilities (LD) using statewide criteria in Greece. Students participated in a 2-year cohort-sequential design. Reading assessments involved measures of…

  18. Energy thrift and improved performance achieved through novel railway brake discs

    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 (ηv) 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

  19. Nursing to achieve organizational performance: Consider the role of nursing intellectual capital.

    Harris, Alexandra

    2016-05-01

    The success and performance of healthcare organizations relies on the strategic management of knowledge. Nursing Intellectual Capital (NIC) has emerged as a concept involving nursing knowledge resources that create value in healthcare organizations. This article aims to discuss the importance of considering knowledge resources in the context of healthcare performance, with specific reference to NIC. Reflections are then provided on how leaders can look to advance NIC for improved performance. PMID:27060807

  20. Achieving High Performance in AC-Field Driven Organic Light Sources

    Junwei Xu; David L. Carroll; Smith, Gregory M.; Chaochao Dun; Yue Cui

    2016-01-01

    Charge balance in organic light emitting structures is essential to simultaneously achieving high brightness and high efficiency. In DC-driven organic light emitting devices (OLEDs), this is relatively straight forward. However, in the newly emerging, capacitive, field-activated AC-driven organic devices, charge balance can be a challenge. In this work we introduce the concept of gating the compensation charge in AC-driven organic devices and demonstrate that this can result in exceptional in...

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

    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......; others 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...

  2. Two-Dimensional Finite Element Ablative Thermal Response Analysis of an Arcjet Stagnation Test

    Dec, John A.; Laub, Bernard; Braun, Robert D.

    2011-01-01

    The finite element ablation and thermal response (FEAtR, hence forth called FEAR) design and analysis program simulates the one, two, or three-dimensional ablation, internal heat conduction, thermal decomposition, and pyrolysis gas flow of thermal protection system materials. As part of a code validation study, two-dimensional axisymmetric results from FEAR are compared to thermal response data obtained from an arc-jet stagnation test in this paper. The results from FEAR are also compared to the two-dimensional axisymmetric computations from the two-dimensional implicit thermal response and ablation program under the same arcjet conditions. The ablating material being used in this arcjet test is phenolic impregnated carbon ablator with an LI-2200 insulator as backup material. The test is performed at the NASA, Ames Research Center Interaction Heating Facility. Spatially distributed computational fluid dynamics solutions for the flow field around the test article are used for the surface boundary conditions.

  3. The Magnetohydrodynamic Stagnation Point Flow of a Nanofluid over a Stretching/Shrinking Sheet with Suction

    Mansur, Syahira; Ishak, Anuar; Pop, Ioan

    2015-01-01

    The magnetohydrodynamic (MHD) stagnation point flow of a nanofluid over a permeable stretching/shrinking sheet is studied. Numerical results are obtained using boundary value problem solver bvp4c in MATLAB for several values of parameters. The numerical results show that dual solutions exist for the shrinking case, while for the stretching case, the solution is unique. A stability analysis is performed to determine the stability of the dual solutions. For the stable solution, the skin friction is higher in the presence of magnetic field and increases when the suction effect is increased. It is also found that increasing the Brownian motion parameter and the thermophoresis parameter reduces the heat transfer rate at the surface. PMID:25760733

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

    Khan, Masood; Malik, Rabia; Hussain, M.

    2016-05-01

    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.

  5. Mass flow rate measurements in two-phase mixtrues with stagnation probes

    Applications of stagnation probes to the measurement of mass flow rate in two-phase flows are discussed. Descriptions of several stagnation devices, which have been evaluated at the Idaho National Engineering Laboratory, are presented along with modeling techniques and two-phase flow data

  6. Mass flow rate measurements in two-phase mixtrues with stagnation probes. [PWR

    Fincke, J.R.; Deason, V.A.

    1979-01-01

    Applications of stagnation probes to the measurement of mass flow rate in two-phase flows are discussed. Descriptions of several stagnation devices, which have been evaluated at the Idaho National Engineering Laboratory, are presented along with modeling techniques and two-phase flow data.

  7. Examining Relationships between Achievement Goals, Study Strategies, and Class Performance in Educational Psychology

    Cao, Li; Nietfeld, John L.

    2007-01-01

    This mixed methods study examined the relationships between students' learning goals, performance goals, study strategies, and test performances over a 14-week undergraduate course in educational psychology. Sixty undergraduate students provided goals at the beginning of the semester and reflected on their goals, study strategies, and test…

  8. Perfectionism and achievement goals in athletes: Relations with approach and avoidance orientations in mastery and performance goals

    Stoeber, Joachim; Stoll, Oliver; Pescheck, Eva; Otto, Kathleen

    2008-01-01

    Objectives: Challenging views that perfectionism is a maladaptive factor in sport and that it is related to a preoccupation with performance goals and a neglect of mastery goals, the present article argues that perfectionism in athletes is not generally maladaptive, but shows differential relationships with mastery and performance goals depending on which facets of perfectionism are regarded. Method: Going beyond the dichotomous achievement goal framework, two studies with N = 204 high sch...

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

    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…

  10. Active commuting to school, cognitive performance, and academic achievement: an observational study in Dutch adolescents using accelerometers

    Van Dijk, Martin; De Groot, Renate; Van Acker, Frederik; Savelberg, Hans; Kirschner, Paul A.

    2014-01-01

    Background: The current study examined the associations between active commuting to school, cognitive performance, and academic achievement in Dutch adolescents. In addition, it was explored whether these associations were moderated by sex and mediated by depressive symptoms. Methods: Students in gr

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

    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…

  12. Conscientiousness, Achievement Striving, and Intelligence as Performance Predictors in a Sample of German Psychology Students: Always a Linear Relationship?

    Ziegler, Matthias; Knogler, Maximilian; Buhner, Markus

    2009-01-01

    Studies on the interface between cognitive ability (intelligence) and personality in the prediction of academic performance have yielded mixed results so far. Especially an interaction between conscientiousness (and its facet achievement striving) and intelligence has been investigated. The hypothesis is that conscientiousness enhances the impact…

  13. The Relationship of Selected Measures of Proprioception to Physical Growth, Motor Performance, and Academic Achievement in Young Children.

    Haubenstricker, John L.; Milne, D. Conrad

    This study investigates the relationship of selected measures of proprioception to measures of physical growth, motor performance, and academic achievement in young children. Measures were obtained from 321 boys and girls attending kindergarten and first and second grade. Sample correlation matrices were computed on all variables at each grade…

  14. Seasonal Reversals of Groundwater Flow Around Lakes and the Relevance to Stagnation Points and Lake Budgets

    Anderson, Mary P.; Munter, James A.

    1981-08-01

    Several researchers have observed seasonal reversals in the direction of groundwater flow around lakes. If these reversals are prolonged and are accompanied by the formation of a stagnation point, they may have a significant effect on a lake's water and nutrient budgets. The formation of a stagnation point at a flow-through lake (i.e., a lake that receives groundwater through part of the lake basin and recharges the groundwater system over the rest of the lake basin) is accomplished by the formation of a groundwater mound on the downgradient side of the lake. In this paper the seasonal formation of a stagnation point at Snake Lake, Wisconsin, is investigated with the aid of two-dimensional transient computer models applied in cross section and areally. The analysis demonstrates the potential for the seasonal formation of a stagnation point at a flow-through lake and provides some insight into the transient development of the stagnation point.

  15. Achieving High Performance Distributed System: Using Grid, Cluster and Cloud Computing

    Sunil Kr Singh; Kavneet Kaur

    2015-01-01

    To increase the efficiency of any task, we require a system that would provide high performance along with flexibilities and cost efficiencies for user. Distributed computing, as we are all aware, has become very popular over the past decade. Distributed computing has three major types, namely, cluster, grid and cloud. In order to develop a high performance distributed system, we need to utilize all the above mentioned three types of computing. In this paper, we shall first have a...

  16. Evaluating the Effect of Teachers' Group Performance Incentives on Pupil Achievement

    Victor Lavy

    2002-01-01

    Proposals to use teachers' performance incentives have recently attracted considerable attention. However, there is very little experience with applying incentives in schools. This paper provides evidence on the causal effects of two programs: the first provided the school and its teachers with monetary performance incentives and the second with additional conventional resources. The assignment of schools to the two programs was not random; therefore, identification is a central issue in the ...

  17. NEMO5: Achieving High-end Internode Communication for Performance Projection Beyond Moore's Law

    Andrawis, Robert; Charles, James; Fang, Jianbin; Fonseca, Jim; He, Yu; Klimeck, Gerhard; Jiang, Zhengping; Kubis, Tillmann; Mejia, Daniel; Lemus, Daniel; Povolotskyi, Michael; Rubiano, Santiago Alonso Perez; Sarangapani, Prasad; Zeng, Lang

    2015-01-01

    Electronic performance predictions of modern nanotransistors require nonequilibrium Green's functions including incoherent scattering on phonons as well as inclusion of random alloy disorder and surface roughness effects. The solution of all these effects is numerically extremely expensive and has to be done on the world's largest supercomputers due to the large memory requirement and the high performance demands on the communication network between the compute nodes. In this work, it is shown that NEMO5 covers all required physical effects and their combination. Furthermore, it is also shown that NEMO5's implementation of the algorithm scales very well up to about 178176CPUs with a sustained performance of about 857 TFLOPS. Therefore, NEMO5 is ready to simulate future nanotransistors.

  18. Coping with stress and cognitive interference in student teachers performance as important factors influencing their achievement

    Cirila Peklaj

    2001-06-01

    Full Text Available The purpose of our study was to investigate the relations between student teachers' strategies for coping with stressful situations, cognitive interference factors and successfulness of presentation of student teachers' seminar work. There were 135 student teachers participating in the study. At the beginning of the semester they filled in the Way of Coping Questionnaire (Folkman & Lazarus, 1988. After their presentation of seminar theme they reported about the cognitive interference factors during the presentation (distractive factors and intrusive thoughts. Different aspects of their performance were also evaluated by the teacher according to the well-known criteria. The analysis of the results showed significant correlations between certain ways of coping, cognitive interference factors and success of performance. Further statistical analysis showed significant differences in experiencing distractive factors and intrusive thoughts during presentation between students with low, medium and high performance success. The importance of successful strategies for coping with verbal presentation and the implications for student teacher education are discussed.

  19. Modified surface loading process for achieving improved performance of the quantum dot-sensitized solar cells

    Liu, Feng; Jin, Zhongxiu; Zhu, Jun; Xu, Yafeng; Zhou, Li; Dai, Songyuan

    2016-06-01

    Achieving high surface coverage of the colloidal quantum dots (QDs) on TiO2 films has been challenging for quantum dot-sensitized solar cells (QDSCs). Herein, a general surface engineering approach was proposed to increase the loading of these QDs. It was found that S2- treatment/QD re-uptake process can significantly improve the attachment of the QDs on TiO2 films. Surface concentration of the QDs was improved by ∼60%, which in turn greatly enhances light absorption and decreases carrier recombination in QDSCs. Ensuing QDSCs with optimized QD loading exhibit a power conversion efficiency of 3.66%, 83% higher than those fabricated with standard procedures.

  20. Use of neurofeedback to achieve human performance enhancement in the nuclear power industry

    The nuclear industry has spent many millions of dollars to provide training to personnel to operate our nuclear facilities. However, even with excellent training programs, candidates often fail examinations. For many, the debilitating effects of performance anxiety are contributing factors. Neurofeedback technology instantly presents psychophysiological feedback to the trainee while the trainee is performing a training task. This feedback can teach the trainee to effectively cope with environmental and psychological stressors. We hypothesize that NF training can help NPPs resolve staffing and training challenges while yielding a high ROI by ultimately improving success rates for Certification training candidates. (author)

  1. The role of mechanization and integration of manufacturing processes in achieving operational performance

    Naqvi, Syed Turab Haider; Farooq, Sami; Johansen, John; Matthiesen, Rikke Vestergaard; Yang, Cheng

    2014-01-01

    Small manufacturing firms are the dominant organization type for most of the developed countries. However, these firms have not been the focus of research and their strategic and operational needs are not extensively addressed by the academic community. Therefore, this research aims at empirically...... finding the impact of mechanization and integration of manufacturing processes and systems on operational performance in small Danish manufacturing firms. We use data of 357 small Danish manufacturing firms and empirically found distinct impact of mechanization and integration of systems on operational...... performance in context of production to order (PTO) and production to stock (PTS) strategies....

  2. Use of neurofeedback to achieve human performance enhancement in the nuclear power industry

    Freer, P. [Freer Logic (United States); Chandler, K. [Univ. of Windsor, Dept. of Kinesiology, Windsor, Ontario (Canada); Lane, L.; Templeton, R. [Ontario Power Generation, Toronto, Ontario (Canada)

    2007-07-01

    The nuclear industry has spent many millions of dollars to provide training to personnel to operate our nuclear facilities. However, even with excellent training programs, candidates often fail examinations. For many, the debilitating effects of performance anxiety are contributing factors. Neurofeedback technology instantly presents psychophysiological feedback to the trainee while the trainee is performing a training task. This feedback can teach the trainee to effectively cope with environmental and psychological stressors. We hypothesize that NF training can help NPPs resolve staffing and training challenges while yielding a high ROI by ultimately improving success rates for Certification training candidates. (author)

  3. "High" Achievers? Cannabis Access and Student Performance. CEP Discussion Paper No. 1340

    Marie, Olivier; Zölitz, Ulf

    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 panel data on over 54,000 course grades of local…

  4. Mayoral Governance and Student Achievement: How Mayor-Led Districts Are Improving School and Student Performance

    Wong, Kenneth K.; Shen, Francis X.

    2013-01-01

    Mayoral control and accountability is one of very few major education reforms that aim at governance coherence in this nation's highly fragmented urban school systems. A primary feature of mayoral governance is that it holds the office of the mayor accountable for school performance. As an institutional redesign, mayoral governance integrates…

  5. The Mental Aspect of Athletics: The Effects of the Mind's Influence on Athletic Achievement and Performance.

    McCollough, David D.

    This study of athletes seeks to determine that a relationship exists between the mind and the body. It presents negative psychological factors that may arise and shows possible ways to enhance athletic performance through psychological techniques. The central part of the study is an annotated bibliography covering selected literature on these…

  6. Effects of Audio- and Videotape Models on Performance Achievement of Beginning Clarinetists.

    Linklater, Fraser

    1997-01-01

    Investigates the effects on home practice of three different types of cassette tapes (a videotape, a modeling audiotape, and a nonmodeling audiotape) on the performance of beginning clarinet students. Finds no significant impact on amount of weekly practice, of practice using tapes, or of parental help based on tape type. (DSK)

  7. How to Achieve the Best SRF Performance: (Practical) Limitations and Possible Solutions

    Antoine, Claire Z

    2014-01-01

    This chapter presents in the first part the requirement for the surface preparation of RF Niobium cavities and its justification in term s of physical origin of limitation (e.g. cleanliness and field emission, influence of the surface treatments, morphology and surface damage, etc.). In the second part we discuss the different models describing the ultimate limits of SRF cavities, and we present one of the possible ways to overcome Niobium monopoly toward higher performances.

  8. Data Quality Monitoring Framework for ATLAS Experiment: Performance Achieved with Colliding Beams at LHC

    Corso-Radu, A; The ATLAS collaboration; Ilchenko, Y; Kolos, S; Okawa, H; Slagle, K; Taffard, A

    2010-01-01

    With the delivery of the first proton-proton collisions by the LHC, the ATLAS collaboration had the opportunity to operate the detector under the environment it was designed for. These first runs have been of great interest not only for the high energy physics outcome, but also were used to perform a general commissioning of the system. The online data quality monitoring framework (DQMF) is a highly scalable distributed framework that is used to assess the quality of the data and the operational conditions of the detector, trigger and data acquisition system. DQMF provides quick feedback to the user about the correct functioning and performance of different parts of the detector, it quickly spots problems related with data quality and allows one to determine the origin of these problems. DQMF performs over forty thousand advanced data quality checks at a rate that depends on the histogram update frequency and it displays histograms and results of these checks on several dozens of monitors installed in the mai...

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

    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

  10. High-performance gas sensing achieved by mesoporous tungsten oxide mesocrystals with increased oxygen vacancies

    Wang, Dong

    2013-01-01

    The inner structure of W18O49 mesocrystals was observed by electron microscopy with the help of ultramicrotomy and focused ion beam techniques. The results showed that these mesocrystals contain irregular mesopores formed through partial fusion of self-assembled nanowires, and consequently have long-range structural ordering in one dimension and short-range ordering in the other two dimensions. The W18O 49 mesocrystals exhibit superior performance in gas sensing applications, which is considered to be associated with the presence of more oxygen vacancy sites in the unique mesoporous structure. © 2013 The Royal Society of Chemistry.

  11. Studies on the impact of achievement motivation on childrens’ performance in the FEW-2

    Peggy Beuthan; Willi Geser; Claudia Schusterschitz

    2012-01-01

    If children in occupational diagnostics solve tasks with suboptimal test motivation, the results of such tests can be falsified. Against that background, the present research aims were to examine, whether there is an influence of children’s test motivation on their performance in the FEW-2, and if their test motivation can be improved by promising a reward. In an experimental field study of 80 healthy and German-speaking children, at the age of 4 to 6 years, data on test motivation were colle...

  12. Exhaust Gas Recirculation Control for Large Diesel Engines - Achievable Performance with SISO Design

    Hansen, Jakob Mahler; Blanke, Mogens; Niemann, Hans Henrik; Vejlgaard-Laursen, Morten

    analysis of the highly non-linear dynamics. Control architectures are investigated and performance in terms of disturbance rejection and reference tracking are investigated under model uncertainty. Classical feed-forward and feedback controller designs are investigated using classical and Quantitative......This paper investigates control possibilities for Exhaust Gas Recirculation (EGR) on large diesel engines. The goal is to reduce the amount of NOx in the exhaust gas by reducing the oxygen concentration available for combustion. Control limitations imposed by the system are assessed using linear...... Feedback Theory (QFT) designs. Validation of the controller is made on the model with focus on disturbance reduction ability....

  13. Studies on the impact of achievement motivation on childrens’ performance in the FEW-2

    Peggy Beuthan

    2012-09-01

    Full Text Available If children in occupational diagnostics solve tasks with suboptimal test motivation, the results of such tests can be falsified. Against that background, the present research aims were to examine, whether there is an influence of children’s test motivation on their performance in the FEW-2, and if their test motivation can be improved by promising a reward. In an experimental field study of 80 healthy and German-speaking children, at the age of 4 to 6 years, data on test motivation were collected and the FEW-2 was performed. To answer the research questions correlation analysis and t-tests for unpaired samples were carried out. The correlation analyses showed an influence of the motivation of the test on the outcomes of the FEW-2, if the claim of other cognitive services, such as, for example, the concentration of power was increased. According to the findings of the t-tests, the reward did not lead to a heightened test motivation amongst the participants of the experimental group. The revealed influence of test motivation on the outcomes of the FEW-2 underlines the necessity to test for test motivation in view of a reliable and valid neuropsychological diagnostic.

  14. Data Quality Monitoring Framework for ATLAS Experiment: Performance Achieved with Colliding Beams at LHC

    Corso-Radu, A; The ATLAS collaboration; Ilchenko, Y; Kolos, S; Okawa, H; Slagle, K; Taffard, A

    2011-01-01

    This first year of data taking has been of great interest, not only for the physics outcome, but also for operating the system under the environment it was designed for. The online data quality monitoring framework (DQMF) is a highly scalable distributed framework which is used to assess the operational conditions of the detector and the quality of the data. DQMF provides quick feedback to the user about the functioning and performance of the sub-detectors by performing over 75,000 advanced data quality checks, with rates varying depending on histogram update frequency. The DQM display (DQMD) is the visualisation tool with which histograms and their data quality assessments can be accessed. It allows for great flexibility for displaying histograms, their reference when applicable, configurations used for the automatics checks, data quality flags and much more. The DQM configuration is stored in a database that can be easily created and edited with the DQM Configurator tool (DQMC). This paper is describing the...

  15. Quality of education predicts performance on the wide range achievement test-4th edition word reading subtest

    Sayegh, P; Arentoft, A; Thaler, NS; Dean, AC; Thames, AD

    2014-01-01

    © The Author 2014. Published by Oxford University Press. All rights reserved. The current study examined whether self-rated education quality predicts Wide Range Achievement Test-4th Edition (WRAT-4) Word Reading subtest and neurocognitive performance, and aimed to establish this subtest's construct validity as an educational quality measure. In a community-based adult sample (N = 106), we tested whether education quality both increased the prediction of Word Reading scores beyond demographic...

  16. Achieving enhanced DSSC performance by microwave plasma incorporation of carbon into TiO2 photoelectrodes

    Dang, Binh H. Q.; MacElroy, Don; Dowling, Denis P.

    2013-06-01

    The photoactivity of carbon-incorporated titanium dioxide (TiO2) has been widely reported. This study involves a novel approach to the incorporation of carbon into TiO2 through the use of microwave plasma processing. The process involved thermally treating printed TiO2 nanoparticle coatings in a microwave-induced argon-oxygen plasma containing low concentrations of methane. The resulting deposited carbon layer was characterized using XRD, XPS, Raman, UV-vis, ellipsometry, and optical profilometry. It was found that the methane gas was dissociated in the microwave plasma into its carbon species, which were then deposited as a nm-thick layer onto the TiO2 coatings, most likely in the form of graphite. The photovoltaic performances of both the TiO2 and the carbon-incorporated TiO2 were assessed through J-V and IPCE measurements of the N719-sensitized solar cells using the titania as their photoanodes. Up to a 72% improvement in the maximum power density (Pd-max) was observed for the carbon-incorporated TiO2 samples as compared to the TiO2, onto which no carbon was added. This improvement was found to be mainly associated with an increase in the short-circuit current density (Jsc), but independent from the open-circuit voltage (Voc), the filter factor (FF), and the level of dye adsorption. Possible contributory factors to the improved performance of the carbon-incorporated TiO2 were the enhanced electron conductivity and electron lifetime, both of which were elucidated through electrochemical impedance spectroscopy (EIS). When the surface layer was examined using XPS, the optimal carbon content on the TiO2 coating surface was found to be 8.4%, beyond which there was a reduction in the DSSC efficiency.

  17. Achieving enhanced DSSC performance by microwave plasma incorporation of carbon into TiO2 photoelectrodes

    The photoactivity of carbon-incorporated titanium dioxide (TiO2) has been widely reported. This study involves a novel approach to the incorporation of carbon into TiO2 through the use of microwave plasma processing. The process involved thermally treating printed TiO2 nanoparticle coatings in a microwave-induced argon-oxygen plasma containing low concentrations of methane. The resulting deposited carbon layer was characterized using XRD, XPS, Raman, UV–vis, ellipsometry, and optical profilometry. It was found that the methane gas was dissociated in the microwave plasma into its carbon species, which were then deposited as a nm-thick layer onto the TiO2 coatings, most likely in the form of graphite. The photovoltaic performances of both the TiO2 and the carbon-incorporated TiO2 were assessed through J-V and IPCE measurements of the N719-sensitized solar cells using the titania as their photoanodes. Up to a 72% improvement in the maximum power density (Pd-max) was observed for the carbon-incorporated TiO2 samples as compared to the TiO2, onto which no carbon was added. This improvement was found to be mainly associated with an increase in the short-circuit current density (Jsc), but independent from the open-circuit voltage (Voc), the filter factor (FF), and the level of dye adsorption. Possible contributory factors to the improved performance of the carbon-incorporated TiO2 were the enhanced electron conductivity and electron lifetime, both of which were elucidated through electrochemical impedance spectroscopy (EIS). When the surface layer was examined using XPS, the optimal carbon content on the TiO2 coating surface was found to be 8.4%, beyond which there was a reduction in the DSSC efficiency.

  18. Wire array z pinch precursors, implosions and stagnation

    Recent measurements of the precursor ablation velocity show that the velocity is reduced significantly when the gap to core size ratio is less than π, implying a higher mass ablation rate and a change in the precursor density profile at the time of implosion. This might explain why experimentally there appears to be an optimal inter-wire gap for the shortest rise time of the x-ray pulse. 2-D kinetic modelling of the precursor plasma shows how long mean-free-path ions can lead to the accumulation of a central dense, radiating column. Precursor interaction with a foam cylinder is also modelled with material mixing allowed. Three effects are being studied that can increase the final x-ray radiation. One is the effect of later implosion of trailing mass, diagnosed by laser probing and modelled by 2-D simulations. A second mechanism is the development of m=1 instabilities and associated increase in ohmic dissipation from current path lengthening. The third is ion viscous heating arising from saturated non-linear, short wavelength MHD m=0 instabilities. Experimental evidence at 20MA on the Z-accelerator shows Doppler broadened spectra at stagnation with ion temperature in the 100-300 keV range, lending support for this last mechanism. (author)

  19. Stagnating Jatropha Biofuel Development in Southwest China: An Institutional Approach

    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.

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

    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, the....... 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...

  1. Transuranics Laboratory, achievements and performance; Laboratorio de Transuranicos, logros y fundamento

    Gasco, C.; Anton, M. P.

    2004-07-01

    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.

  2. Rankings of International Achievement Test Performance and Economic Strength: Correlation or Conjecture?

    CHRISTOPHER H. TIENKEN

    2008-04-01

    Full Text Available Examining a popular political notion, this article presents results from a series of Spearman Rho calculations conducted to investigate relationships between countries’ rankings on international tests of mathematics and science and future economic competitiveness as measured by the 2006 World Economic Forum’s Growth Competitiveness Index (GCI. The study investigated the existence of relationships between international test rankings from three different time periods during the last 50 years of U.S. education policy development (i.e., 1957–1982, 1983–2000, and 2001–2006 and 2006 GCI ranks. It extends previous research on the topic by investigating how GCI rankings in the top 50 percent and bottom 50 percent relate to rankings on international tests for the countries that participated in each test. The study found that the relationship between ranks on international tests of mathematics and science and future economic strength is stronger among nations with lower-performing economies. Nations with strong economies, such as the United States, demonstrate a weaker, nonsignificant relationship.

  3. Tuning interactions between zeolite and supported metal by physical-sputtering to achieve higher catalytic performances.

    Li, Xin-Gang; Liu, Cheng; Sun, Jian; Xian, Hui; Tan, Yi-Sheng; Jiang, Zheng; Taguchi, Akira; Inoue, Mitsuhiro; Yoneyama, Yoshiharu; Abe, Takayuki; Tsubaki, Noritatsu

    2013-01-01

    To substitute for petroleum, Fischer-Tropsch synthesis (FTS) is an environmentally benign process to produce synthetic diesel (n-paraffin) from syngas. Industrially, the synthetic gasoline (iso-paraffin) can be produced with a FTS process followed by isomerization and hydrocracking processes over solid-acid catalysts. Herein, we demonstrate a cobalt nano-catalyst synthesized by physical-sputtering method that the metallic cobalt nano-particles homogeneously disperse on the H-ZSM5 zeolite support with weak Metal-Support Interactions (MSI). This catalyst performed the high gasoline-range iso-paraffin productivity through the combined FTS, isomerization and hydrocracking reactions. The weak MSI results in the easy reducibility of the cobalt nano-particles; the high cobalt dispersion accelerates n-paraffin diffusion to the neighboring acidic sites on the H-ZSM5 support for isomerization and hydrocracking. Both factors guarantee its high CO conversion and iso-paraffin selectivity. This physical-sputtering technique to synthesize the supported metallic nano-catalyst is a promising way to solve the critical problems caused by strong MSI for various processes. PMID:24085106

  4. ITC SOLUTIONS TO ACHIEVE PERFORMANCE AND EFFICIENCY OF HEALTH SERVICES: ONLINE VIRTUAL CLINIC

    Adina BĂLAN

    2010-01-01

    Full Text Available The digital era modified the way people work, how the information and the informational resources are defined and organized. The organization which holds, uses and correctly reproduces the piece of information, the knowledge, the intellectual capital, becomes a leader in the proper field of activity. Following the actual tendencies in the digital era connected to the exchange of professional information, I can say that the exchange and sharing of digital information in a global multitude of interconnected computers are essential instruments that can contribute to the development and consolidation of the intellectual potential of the organization. This is why, the access of the individuals to information is an actual requirement of the development of the Romanian society in the context of globalization and world implication o contemporary processes and phenomena. The Digital integration eliminates the barriers that traditionally suppress the circuit of the medical information, lets the goods and services circulate to and from Romania by promoting efficiency as final purpose. Performance is needed in the health system, the transformation of the system of medical services by bringing the benefits of the medical science and technology to all individuals from every community. In order to accomplish these expectations it is needed that all the components that form the health system look at it as a whole and subscribe to modern solutions for improvement so that the quality of health should raise to an unprecedented level. Even if health systems differ from country to country from the organizational and financial point of view, they face the same challenges and problems, respectively the supply of medical care of better quality and keeping under control the health expenses. The use of information and communication technology in the field of medical assistance in order to stock, share, transmit and analyze clinical data and knowledge is more necessary

  5. Achieving transparency in the total system performance assessment of a potential high level radioactive waste repository at Yucca Mountain, Nevada

    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

  6. Safe, Non-Corrosive Dielectric Fluid for Stagnating Radiator Thermal Control System Project

    National Aeronautics and Space Administration — Paragon Space Development Corporation proposes to develop a single-loop, non-toxic, active pumped radiator design with robust, reliable operation near stagnation...

  7. Predictive Gust Load Alleviation Control Using Leading Edge Stagnation Point Sensor Project

    National Aeronautics and Space Administration — ZONA Technology, Inc proposes an R&D effort to develop a Gust Load Alleviation (GLA) control system using a novel Leading Edge Stagnation Point (LESP) sensor...

  8. Analytic Solution for Magnetohydrodynamic Stagnation Point Flow towards a Stretching Sheet

    DING Qi; ZHANG Hong-Qing

    2009-01-01

    A steady two-dimensional magnetohydrodynamic stagnation point flow towards a stretching sheet with variable surface temperature is investigated. The analytic solution is obtained by homotopy analysis method. Theconvergence region is computed and the feature of the solution is discussed.

  9. Safe, Non-Corrosive Dielectric Fluid for Stagnating Radiator Thermal Control System Project

    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)...

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

    Al-Alwan Ibrahim

    2009-01-01

    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 in...

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

    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 Sm0.20Ce0.80O2−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

  12. Multimedia OC12 parallel interface using VCSEL array to achieve high-performance cost-effective optical interconnections

    Chang, Edward S.

    1996-09-01

    ribbon cable, and MT connectors to achieve a high-performance, low-cost parallel link. A logical model of a multimedia server with parallel connections to an ATM switch, and to clients is presented. The design of the parallel optical link is analyzed. Furthermore, the link configured for testing, the test method, and test results are presented to confirm the analysis and to assure reliable link performance.

  13. Quality of education predicts performance on the Wide Range Achievement Test-4th Edition Word Reading subtest.

    Sayegh, Philip; Arentoft, Alyssa; Thaler, Nicholas S; Dean, Andy C; Thames, April D

    2014-12-01

    The current study examined whether self-rated education quality predicts Wide Range Achievement Test-4th Edition (WRAT-4) Word Reading subtest and neurocognitive performance, and aimed to establish this subtest's construct validity as an educational quality measure. In a community-based adult sample (N = 106), we tested whether education quality both increased the prediction of Word Reading scores beyond demographic variables and predicted global neurocognitive functioning after adjusting for WRAT-4. As expected, race/ethnicity and education predicted WRAT-4 reading performance. Hierarchical regression revealed that when including education quality, the amount of WRAT-4's explained variance increased significantly, with race/ethnicity and both education quality and years as significant predictors. Finally, WRAT-4 scores, but not education quality, predicted neurocognitive performance. Results support WRAT-4 Word Reading as a valid proxy measure for education quality and a key predictor of neurocognitive performance. Future research should examine these findings in larger, more diverse samples to determine their robust nature. PMID:25404004

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

    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

  15. Functional Organosulfide Electrolyte Promotes an Alternate Reaction Pathway to Achieve High Performance in Lithium-Sulfur Batteries.

    Chen, Shuru; Dai, Fang; Gordin, Mikhail L; Yu, Zhaoxin; Gao, Yue; Song, Jiangxuan; Wang, Donghai

    2016-03-18

    Lithium-sulfur (Li-S) batteries have recently received great attention because they promise to provide energy density far beyond current lithium ion batteries. Typically, Li-S batteries operate by conversion of sulfur to reversibly form different soluble lithium polysulfide intermediates and insoluble lithium sulfides through multistep redox reactions. Herein, we report a functional electrolyte system incorporating dimethyl disulfide as a co-solvent that enables a new electrochemical reduction pathway for sulfur cathodes. This pathway uses soluble dimethyl polysulfides and lithium organosulfides as intermediates and products, which can boost cell capacity and lead to improved discharge-charge reversibility and cycling performance of sulfur cathodes. This electrolyte system can potentially enable Li-S batteries to achieve high energy density. PMID:26918660

  16. Stagnation of a droplet on a conical substrate determined by the critical curvature ratio

    Li, YingQi; Wu, HengAn; Wang, FengChao

    2016-03-01

    In this work, we studied the effect of the curvature ratio, which is defined as the ratio of the local substrate radii to droplet radii, on the spontaneous directed movement and stagnation of a droplet on a conical substrate. The stagnation phenomenon emerged when the ratio exceeded a critical value. We found that the moving process of the droplet from the tip to the base of the conical substrate can be divided into three stages based on the critical curvature ratio. In order, these comprise: the fast-moving stage (S1) where the droplet obtains large driving force and resistance force, which are resulted from large contact line and contact angle difference between the two opposite sides of the droplet, respectively; the short transition stage (S2) where the droplet morphology tends to be symmetry, both driving force and resistance force decrease rapidly to a low level; and the stagnation stage (S3) where the curvature ratio is much larger than the critical value. Both driving force and resistance force approach zero, the droplet stagnates at the local substrate instead of moving forward. The curvature ratio based theoretical analyses of free energy, driving force and resistance force are in good consistence with simulation results, and can well describe the moving process and the stagnation phenomenon of the droplet on the conical substrate.

  17. Intellectual and non-intellectual determinants of high academic achievement – the contribution of personality traits to the assessment of high performance potential

    Silvia Schubhart

    2013-09-01

    Full Text Available In this paper a study is presented which tries to explain and predict high academic achievement in children or adolescents on the basis of intellectual and non-intellectual determinants – in this case, performance relevant personality traits as well as the social environment of stimulation. The prognosis of high academic achievement is based on a new diagnostic model, the Viennese Diagnostic Model of High Achievement Potential, which undergoes its first empirical validation here. The results show impressive evidence that performance-relevant personality traits and categories of social environment of stimulation contribute to high academic achievement in children and adolescents of above-average intelligence.

  18. MHD Stagnation Flow of a Newtonian Fluid towards a Uniformly Heated and Moving Vertical Plate

    Mehmet Şirin Demir

    2016-01-01

    Full Text Available Stagnation flow of an electrically conducting incompressible viscous fluid towards a moving vertical plate in the presence of a constant magnetic field is investigated. By using the appropriate transformations for the velocity components and temperature, the partial differential equations governing flow and heat transfer are reduced to a set of nonlinear ordinary differential equations. These equations are solved approximately using a numerical technique for the following two problems: (i two-dimensional stagnation-point flow on a moving vertical plate, (ii axisymmetric stagnation-point flow on a moving vertical plate. The effects of non-dimensional parameters on the velocity components, wall shear stresses, temperature and heat transfer are examined carefully.

  19. A strategy for reducing stagnation phase hydrodynamic instability growth in inertial confinement fusion implosions

    Clark, D. S.; Robey, H. F.; Smalyuk, V. A. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550 (United States)

    2015-05-15

    Encouraging progress is being made in demonstrating control of ablation front hydrodynamic instability growth in inertial confinement fusion implosion experiments on the National Ignition Facility [E. I. Moses, R. N. Boyd, B. A. Remington, C. J. Keane, and R. Al-Ayat, Phys. Plasmas 16, 041006 (2009)]. Even once ablation front stabilities are controlled, however, instability during the stagnation phase of the implosion can still quench ignition. A scheme is proposed to reduce the growth of stagnation phase instabilities through the reverse of the “adiabat shaping” mechanism proposed to control ablation front growth. Two-dimensional radiation hydrodynamics simulations confirm that improved stagnation phase stability should be possible without compromising fuel compression.

  20. A strategy for reducing stagnation phase hydrodynamic instability growth in inertial confinement fusion implosions

    Encouraging progress is being made in demonstrating control of ablation front hydrodynamic instability growth in inertial confinement fusion implosion experiments on the National Ignition Facility [E. I. Moses, R. N. Boyd, B. A. Remington, C. J. Keane, and R. Al-Ayat, Phys. Plasmas 16, 041006 (2009)]. Even once ablation front stabilities are controlled, however, instability during the stagnation phase of the implosion can still quench ignition. A scheme is proposed to reduce the growth of stagnation phase instabilities through the reverse of the “adiabat shaping” mechanism proposed to control ablation front growth. Two-dimensional radiation hydrodynamics simulations confirm that improved stagnation phase stability should be possible without compromising fuel compression

  1. Use of Utility Codes for Fuel Analysis during Off-Stagnation Feeder Break in CANDU

    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. For an inlet feeder break which is slightly larger or smaller than that for the stagnation break case, the result is a channel flow which is low enough to result in fuel failure but high enough that the pressure tube remains intact. This event is identified as the off-stagnation break. In this report, the fuel analysis methodology and the usage of utility codes to evaluate the fission gas release during the off-stagnation feeder break are described. 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. After starting the off-stagnation break, ELOCA code evaluated the timing of fuel failure and the following fission gas release due to the oxidation of the pellet are calculated by using several utility codes until the reactor trip. The calculated fission product releases are provided to the following dose assessment as a source term

  2. Intellectual and non-intellectual determinants of high academic achievement – the contribution of personality traits to the assessment of high performance potential

    Silvia Schubhart; Stefana Holocher-Ertl; Georg Wilflinger

    2013-01-01

    In this paper a study is presented which tries to explain and predict high academic achievement in children or adolescents on the basis of intellectual and non-intellectual determinants – in this case, performance relevant personality traits as well as the social environment of stimulation. The prognosis of high academic achievement is based on a new diagnostic model, the Viennese Diagnostic Model of High Achievement Potential, which undergoes its first empirical validation here. The resu...

  3. 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

    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…

  4. DTC-SVM Based on PI Torque and PI Flux Controllers to Achieve High Performance of Induction Motor

    Hassan Farhan Rashag

    2014-01-01

    Full Text Available The fundamental idea of direct torque control of induction machines is investigated in order to emphasize the property produced by a given voltage vector on stator flux and torque variations. The proposed control system is based on Space Vector Modulation (SVM of electrical machines, Improvement model reference adaptive system, real time of stator resistance and estimation of stator flux. The purpose of this control is to minimize electromagnetic torque and flux ripple and minimizing distortion of stator current. In this proposed method, PI torque and PI flux controller are designed to achieve estimated torque and flux with good tracking and fast response with reference torque and there is no steady state error. In addition, design of PI torque and PI flux controller are used to optimize voltages in d-q reference frame that applied to SVM. The simulation Results of proposed DTC-SVM have complete excellent performance in steady and transient states as compared with classical DTC-SVM.

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

    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

  6. Economic stagnation postponed: background of the 2008 financial-economic crisis in the European Union and the United States

    G. Reuten

    2011-01-01

    The significant increase since the early 1980s in the share of income accruing to capital (rather than labor), in both the United States and the European Union, created the potential for economic stagnation. Stagnation was postponed, however, by the development of the banking sector in these countri

  7. Stagnation-point flow of the Walters' B' fluid with slip

    F. Labropulu

    2004-01-01

    Full Text Available The steady two-dimensional stagnation point flow of a non-Newtonian Walters' B' fluid with slip is studied. The fluid impinges on the wall either orthogonally or obliquely. A finite difference technique is employed to obtain solutions.

  8. TCM Treatment of Lumbago Due to Qi Stagnation in the Liver and Gallbladder

    王彦辉

    2004-01-01

    @@ As we know, lumbago falls into the category of bi syndrome. It is mainly caused by the external pathogens, such as wind, cold, heat or dampness in the meridians and collaterals. Actually, the emotional disorder, and Zang and Fu damage can also lead to liver stagnation and finally the bi syndrome.

  9. An application of interacting shear flows theory: exact solution for unsteady oblique stagnation point flow

    Guibo Li; Minguo Dai; Zhi Gao

    2006-01-01

    An analytical solution of the governing equations of the interacting shear flows for unsteady oblique stagnation point flow is obtained. It has the same form as that of the exact solution obtained from the complete NS equations and physical analysis and relevant discussions are then presented.

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

    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.

  11. Stagnating crop yields: An overlooked risk for the carbon balance of agricultural soils?

    Wiesmeier, Martin; Hübner, Rico; Kögel-Knabner, Ingrid

    2015-12-01

    The carbon (C) balance of agricultural soils may be largely affected by climate change. Increasing temperatures are discussed to cause a loss of soil organic carbon (SOC) due to enhanced decomposition of soil organic matter, which has a high intrinsic temperature sensitivity. On the other hand, several modeling studies assumed that potential SOC losses would be compensated or even outperformed by an increased C input by crop residues into agricultural soils. This assumption was based on a predicted general increase of net primary productivity (NPP) as a result of the CO2 fertilization effect and prolonged growing seasons. However, it is questionable if the crop C input into agricultural soils can be derived from NPP predictions of vegetation models. The C input in European croplands is largely controlled by the agricultural management and was strongly related to the development of crop yields in the last decades. Thus, a glance at past yield development will probably be more instructive for future estimations of the C input than previous modeling approaches based on NPP predictions. An analysis of European yield statistics indicated that yields of wheat, barley and maize are stagnating in Central and Northern Europe since the 1990s. The stagnation of crop yields can probably be related to a fundamental change of the agricultural management and to climate change effects. It is assumed that the soil C input is concurrently stagnating which would necessarily lead to a decrease of agricultural SOC stocks in the long-term given a constant temperature increase. Remarkably, for almost all European countries that are faced with yield stagnation indications for agricultural SOC decreases were already found. Potentially adverse effects of yield stagnation on the C balance of croplands call for an interdisciplinary investigation of its causes and a comprehensive monitoring of SOC stocks in agricultural soils of Europe. PMID:26235605

  12. Correlations among Six Learner Variables and the Performance of a Sample of Jamaican Eleventh-Graders on an Achievement Test on Respiration

    Soyibo, Kola; Pinnock, Jacqueline

    2005-01-01

    This study aimed at establishing if the level of performance of 500 Jamaican Grade 11 students on an achievement test on the concept of respiration was satisfactory (mean = 28 or 70% and above) or not (less than 70%); if there were statistically significant differences in their performance on the concept linked to their gender, cognitive abilities…

  13. A meta-analytic review of the approach-avoidance achievement goals and performance relationships in the sport psychology literature

    Marc Lochbaum

    2015-06-01

    Conclusion: The performance goal contrast holds value for sport performance research. Contrary to approach-avoidance predictions, the mastery-approach goal and performance effect size was significant and of equal magnitude as the performance approach goal and performance effect size. Thus, future research should closely test the efficacy of both the mastery- and performance contrasts in impacting performance of sport tasks. Last, the significant effect sizes reported in this review are in stark contrast to contemporary meta-analytic findings in education. Differences in the approach-avoidance goals in sport and education relative to performance should be researched further.

  14. Fifteen Years of Collaborative Innovation and Achievement: NASA Nebraska Space Grant Consortium 15-Year Program Performance and Results Report

    Schaaf, Michaela M.; Bowen, Brent D.; Fink, Mary M.; Nickerson, Jocelyn S.; Avery, Shelly; Carstenson, Larry; Dugan, James; Farritor, Shane; Joyce, James; Rebrovich, Barb

    2003-01-01

    Condensing five years of significant work into a brief narrative fitting PPR requirements gave the affiliates of the Nebraska Space Grant a valuable chance for reflection. Achievements of Space Grant in Nebraska were judiciously chosen for this document that best illustrate the resultant synergism of this consortium, keeping in mind that these examples are only a representation of greater activity throughout the state. Following are highlights of many of the finer and personal achievements for Nebraska Space Grant. The Consortium welcomes inquiries to elaborate on any of these accomplishments.

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

    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.

  16. A numerical study of hypersonic stagnation heat transfer predictions at a coordinate singularity

    Grasso, Francesco; Gnoffo, Peter A.

    1990-01-01

    The problem of grid induced errors associated with a coordinate singularity on heating predictions in the stagnation region of a three-dimensional body in hypersonic flow is examined. The test problem is for Mach 10 flow over an Aeroassist Flight Experiment configuration. This configuration is composed of an elliptic nose, a raked elliptic cone, and a circular shoulder. Irregularities in the heating predictions in the vicinity of the coordinate singularity, located at the axis of the elliptic nose near the stagnation point, are examined with respect to grid refinement and grid restructuring. The algorithm is derived using a finite-volume formulation. An upwind-biased total-variation diminishing scheme is employed for the inviscid flux contribution, and central differences are used for the viscous terms.

  17. Microfluidic-based single cell trapping using a combination of stagnation point flow and physical barrier

    Yu, Miao; Chen, Zongzheng; Xiang, Cheng; Liu, Bo; Xie, Handi; Qin, Kairong

    2016-03-01

    Single cell trapping in vitro by microfluidic device is an emerging approach for the study of the relationship between single cells and their dynamic biochemical microenvironments. In this paper, a hydrodynamic-based microfluidic device for single cell trapping is designed using a combination of stagnation point flow and physical barrier. The microfluidic device overcomes the weakness of the traditional ones, which have been only based upon either stagnation point flows or physical barriers, and can conveniently load dynamic biochemical signals to the trapped cell. In addition, it can connect with a programmable syringe pump and a microscope to constitute an integrated experimental system. It is experimentally verified that the microfluidic system can trap single cells in vitro even under flow disturbance and conveniently load biochemical signals to the trapped cell. The designed micro-device would provide a simple yet effective experimental platform for further study of the interactions between single cells and their microenvironments.

  18. Mechanism and numerical simulation of pressure stagnation during water jetting perforation

    Huang Zhongwei; Li Gensheng; Tian Shouceng; Shen Zhonghou; Luo Hongbin

    2008-01-01

    When perforating with an abrasive water jet, it is possible that the pressure in the hole (perforation) will be higher than that in the annulus because of water jet blasting against the hole wall,which also is the theoretical basis for the technology of hydro-jet fracturing. This paper analyzes the mechanism of generating pressure stagnation in water jet hole, and puts forward a new concept of hydroseal. Then, the distribution of pressure in the hole was simulated with the finite element method. The simulation results showed that the pressure in the hole was higher than that in the annulus. Also, the lower the annular pressure (confining pressure) and the higher the blasting pressure, the greater the pressure difference. An experiment indicated that the cement sample was lifted up under the pressure stagnation in the hole, which proved the finite element simulation results obviously.

  19. Microfluidic-based single cell trapping using a combination of stagnation point flow and physical barrier

    Yu, Miao; Chen, Zongzheng; Xiang, Cheng; Liu, Bo; Xie, Handi; Qin, Kairong

    2016-06-01

    Single cell trapping in vitro by microfluidic device is an emerging approach for the study of the relationship between single cells and their dynamic biochemical microenvironments. In this paper, a hydrodynamic-based microfluidic device for single cell trapping is designed using a combination of stagnation point flow and physical barrier. The microfluidic device overcomes the weakness of the traditional ones, which have been only based upon either stagnation point flows or physical barriers, and can conveniently load dynamic biochemical signals to the trapped cell. In addition, it can connect with a programmable syringe pump and a microscope to constitute an integrated experimental system. It is experimentally verified that the microfluidic system can trap single cells in vitro even under flow disturbance and conveniently load biochemical signals to the trapped cell. The designed micro-device would provide a simple yet effective experimental platform for further study of the interactions between single cells and their microenvironments.

  20. Regional income convergence, skilled migration and productivity response: Explaining relative stagnation in the periphery

    Joern Rattsoe; Hildegunn Ekroll Stokke

    2009-01-01

    Most country growth experiences imply urbanization with labor migration from poor to rich regions and relative stagnation in the periphery. We study mechanisms holding back regional income convergence emphasizing the importance of productivity. Recent research has addressed the effects of labor mobility for income convergence in the neoclassical growth model, but finds that migration has limited effect on the convergence process. We build skilled labor migration into a multi-regional neoclass...

  1. TRANSFORMATION VERSUS STAGNATION IN THE OIL PALM INDUSTRY: A COMPARISON BETWEEN MALAYSIA AND NIGERIA

    Kajisa, Kei; Maredia, Mywish K.; Boughton, Duncan

    1997-01-01

    This paper contrasts the successful transformation of the oil palm sector in Malaysia with the stagnation of the oil palm sector in Nigeria, and examines the factors determining the different paths that the oil palm sectors took in these two countries with the aim of drawing lessons for future development and transfer strategy in Nigeria. Comparing two countries in different regions is not easy, especially when Nigeria has been in political chaos and the agro-climatic environments for oil-pal...

  2. Flow and heat transfer at a general three-dimensional stagnation point in a nanofluid

    Bachok, Norfifah [Department of Mathematics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Ishak, Anuar, E-mail: anuarishak@yahoo.co [School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Institute of Mathematical Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Nazar, Roslinda [School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Pop, Ioan [Faculty of Mathematics, University of Cluj, R-3400 Cluj, CP 253 (Romania)

    2010-12-15

    The problem dealing with steady three-dimensional stagnation point flow in a nanofluid is investigated. By using appropriate transformation for velocity and temperature, the basic equations governing the flow and heat transfer are reduced to a set of ordinary differential equations. These equations subjected to the associated boundary conditions are then solved numerically. The effects of the nanoparticle volume fraction {phi} and the ratio of the gradient of velocities c on the flow and heat transfer characteristics are thoroughly examined.

  3. Stagnation-Point Flow towards a Stretching Vertical Sheet with Slip Effects

    Khairy Zaimi; Anuar Ishak

    2016-01-01

    The effects of partial slip on stagnation-point flow and heat transfer due to a stretching vertical sheet is investigated. Using a similarity transformation, the governing partial differential equations are reduced into a system of nonlinear ordinary differential equations. The resulting equations are solved numerically using a shooting method. The effect of slip and buoyancy parameters on the velocity, temperature, skin friction coefficient and the local Nusselt number are graphically presen...

  4. Heat flux measurements in stagnation point methane/air flames with thermographic phosphors

    Salem, Mohamed; Staude, Susanne; Bergmann, Ulf; Atakan, Burak

    2010-10-01

    Light-induced phosphorescence from thermographic phosphors was used to study the wall temperatures and heat fluxes from nearly one-dimensional flat premixed flames. The investigated flames were stoichiometric, lean and rich laminar methane/air flames with equivalence ratios of φ = 1, φ = 0.75 and φ = 1.25 at ambient pressure. The flames were burning in a stagnation point arrangement against a water-cooled plate. 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 to 1.2 m/s. The burner to plate distance (H) ranged from 0.5 to 2 times the burner exit diameter ( d = 30 mm). The measured heat flux rates 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, gas phase temperatures were measured by OH-LIF for a stoichiometric stagnation point flame. It turns out that the flame stabilization mechanism and with it the heat fluxes change from low to high mass fluxes. This geometry may be well suited for further studies of the elementary flame wall interaction.

  5. Mathematical Analysis of the Historical Economic Growth with a Search for Takeoffs from Stagnation to Growth

    Nielsen, Ron W

    2016-01-01

    Abstract. Data describing historical economic growth are analysed. Included in the analysis is the world and regional economic growth. The analysis demonstrates that historical economic growth had a natural tendency to follow hyperbolic distributions. Parameters describing hyperbolic distributions have been determined. A search for takeoffs from stagnation to growth produced negative results. This analysis throws a new light on the interpretation of the mechanism of the historical economic gr...

  6. Founders and Financially Affiliated Directors on Charter School Boards and Their Impact on Financial Performance and Academic Achievement

    Charisse A. Gulosin; Elif Sisli-Ciamarra

    2012-01-01

    This study uses a hand-collected dataset for charter school boards in Massachusetts between 2001 and 2009 to examine the relationship between financial performance and the presence of founders and financially affiliated directors. School-level financial performance suggests that founder presence on a board has a negative effect on both financial and academic performance of a charter school. On the other hand, the presence of financially affiliated directors on the charter school governing boa...

  7. Stagnation temperature in a cold hypersonic flow produced by a light free piston compression facility

    Widodo, Agung; Buttsworth, David

    2013-04-01

    Stagnation temperatures at the nozzle exit of the University of Southern Queensland hypersonic wind tunnel facility have been identified using an aspirating tube device with a 0.075 mm diameter k-type butt-welded thermocouple junction positioned at its inlet. Because of the finite thermal inertia of the thermocouple, a response time correction is introduced, and uncertainties in the response time correction are assessed and minimized by operating the aspirating device over a range of different initial temperatures. Pressure measurements within the barrel of the wind tunnel facility were used to estimate a theoretical upper bound on the flow stagnation temperature by assuming isentropic compression of the test gas. Results demonstrate that for the current operating conditions, the gas which is first delivered into the hypersonic nozzle has a stagnation temperature almost identical to the isentropic compression value of around 560 K, but a cooling effect is registered for the duration of the test flow which is about 200 ms. Thermodynamic simulations based on an unsteady energy balance model with turbulent heat transfer from the test gas within the barrel demonstrate a cooling effect of a similar magnitude to that indicated by the measured temperature variation, suggesting that strong mixing of the test gas occurs within the barrel during flow discharge through the hypersonic nozzle.

  8. The effect of retesting on end-of-semester performance in high school chemistry at three levels of previous science achievement

    Deboer, George E.

    To determine the effect of retesting on student learning in chemistry, three questions were addressed by means of a 3 × 2 (achievement level X treatment) factorial design: (1) Does retesting affect differently the end-of-semester mastery of course objectives of students who are grouped according to their previous achievement in science? (2) Do students who are given an opportunity to take retests merely delay their studying and perform at a lower level on initial tests than nonretested students? (3) Is the procrastination of retested students (if it exists) affected by their achievement level? The results showed that for one of four units low ability students who were retested demonstrated greater learning gains than low ability students who were not retested, and that procrastination, if it was present, did not have significant effects on student learning at any achievement level. Results were discussed in terms of the students' room for improvement, motivation to improve, and ability to improve.

  9. The Effects of Intercollegiate Athletic Participation on Student Academic Achievement and Leadership Performance in a Selective Institution

    Yunker, Craig Andrew

    2009-01-01

    The purpose of this study was to examine the influence of various intensity levels of athletic participation on academic and leadership performance in a selective institution. For the purpose of this study a retrospective analysis of existing admissions and student performance data was conducted. The continuous dependent variables were academic…

  10. Patterns and Predictors of Adolescent Academic Achievement and Performance in a Sample of Children with Attention-Deficit/Hyperactivity Disorder (ADHD)

    Langberg, Joshua M.; Molina, Brooke S.G.; Arnold, L. Eugene; Epstein, Jeffery N.; Altaye, Mekibib; Hinshaw, Stephen P.; Swanson, James M.; Wigal, Timothy; Hechtman, Lily

    2011-01-01

    Examined predictors of academic achievement, measured by standardized test scores, and performance, measured by school grades, in adolescents (Mage=16.8 yr) who met diagnostic criteria for ADHD-Combined type in early childhood (Mage = 8.5; N = 579). Several mediation models were also tested to determine whether ADHD medication use, receipt of special education, classroom performance, homework completion, or homework management mediated the relationship between symptoms of ADHD and academic ou...

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

    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, Unit

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

    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. doi:10.1016/

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

    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

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

    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 image velocimetry in order to quantitatively measure the fluid dynamics both before and after the jet exits its nozzle. The velocity profiles are normalised with the mean velocity across the nozzle exit, and turbulence statistics are also presented. The primary objective of this paper is to present accurate flow profiles across the nozzle exit of an impinging jet confined to a low H/ D, with a view to guide the boundary conditions chosen for numerical simulations confined to similar constraints. The results revealed in this paper suggest that the fluid dynamics in the stagnation zone strongly influences the nozzle exit velocity profile at confinement heights between 0 0.5—where D is the inner diameter of the jet—in order to minimise modelling uncertainty.

  15. Ice mechanics, basal water and the stagnation of Kamb Ice Stream, Antarctica

    Fried, M.; Hulbe, C. L.; Fahnestock, M. A.

    2012-12-01

    Several of the ice streams that move ice from the interior of the West Antarctic Ice Sheet (WAIS) to the Ross Ice Shelf are documented to stagnate and reactivate on multi-century time scales. Once such event may now be underway on the downstream ice plain of the Whillans Ice Stream (WIS), a stream that stopped and started between about 850 and 450 years ago. Kamb Ice Stream (KIS) ceased its rapid flow about 150 years ago in an event that appears to have initiated in the downstream reach of the ice stream. These switches from fast to slow and back again produce major changes in mass balance of the ice sheet and ice shelf system. Ice stream stagnation must in some way involve changes in the basal water that facilitates fast flow. Here, transients in ice thickness and surface slope, which together steer basal water, are examined in the context of the recent stagnation of KIS. Transients have both regional—changes in WIS flux and in Crary Ice Rise, for example—and local causes. A mechanical analysis of high-resolution surface elevation and ice velocity data sets on the now-active WIS is used as a proxy for past conditions on KIS and an ice flow model is used to place those local conditions in a regional context. We argue that thickness transients associated with stagnation of WIS required the KIS grounding line to retreat far upstream of its present location while reactivation of WIS led to regional thickening, grounding of floating ice, and advance of the KIS grounding line toward its present location. The present work examines the role of lateral margins near the grounding line, in particular the broad, flat, "Duckfoot" on the right lateral side of the KIS outlet and Lake Englehardt, which occupies the same postion at the outlet of WIS. Lake Englehardt diverts water away from the main trunk of the ice stream. In the past, the Duckfoot may have played a similar role and that diversion may have been associated with KIS stagnation. Overall, our aim is to understand

  16. Building trust through promises and performance. Can your organization achieve the stellar results and employee loyalty found at Southwest Airlines?

    O'Connor, Edward J; Annison, Michael H

    2002-01-01

    Establishing a trusting relationship with your employees can help you transform your organization into a top performer. Examine how well-defined visions and goals are some of the keys to building that trust. PMID:11806234

  17. Self-Organizing Maps For Knowledge Discovery From Corporate Databases To Develop Risk Based Prioritization For Stagnation 

    Mounce, S.R.; Sharpe, R.; Speight, V.; Holden, B; Boxall, J

    2015-01-01

    Stagnation or low turnover of water within water distribution systems may result in water quality issues, even for relatively short durations of stagnation / low turnover if other factors such as deteriorated aging pipe infrastructure are present. As leakage management strategies, including the creation of smaller pressure management zones, are implemented increasingly more dead ends are being created within networks and hence potentially there is an increasing risk to water quality due to st...

  18. A cross-country comparison of math achievement at teen age and cognitive performance 40 years later

    Vegard Skirbekk; Valeria Bordone; Daniela Weber

    2014-01-01

    Background: Maintaining cognitive functioning through mid- to late-life is relevant for the individual and societal aim of active ageing. Evidence shows considerable stability in individual-level rank-ordering of cognitive functioning, but little attention has been given to cohort performance over the life cycle and macro-level factors that could affect it. Objective: The main goal of this paper is to address cross-national variation in mental performance from younger to older ages. Met...

  19. Attendance and Achievement in Medicine: Investigating the Impact of Attendance Policies on Academic Performance of Medical Students

    Subramaniam, BS; Hande, S; Komattil, R

    2013-01-01

    Background: The attendance mandate for the medical course in Melaka Manipal Medical College, Manipal, India was increased from 75% to 90% based on the assumption that the mandatory increase will improve the students’ performance. Aims: To find out whether there is any correlation between class attendance and academic performance. Subjects and Methods: This was an institution based retrospective analytical study. Students who have completed Phase I (first two and a half years) of the MBBS cour...

  20. An Initial Study of Relationships among the R&D Productivities of Patent Inventors in Patent, Academic Achievement and Professional Performances - An Example of Pixar Animation Studies

    Mei-Yin Chen

    2004-09-01

    Full Text Available Patent information is seen to be a kind of information with the features of exactitude and trustfulness, and it can be used as an indicator to measure the capability of research and development in a company. This research initially explores the relationships among the R&D productivities of patent inventors in patents, academic achievements and professional performances in terms of a patent production aspect. Our research object is the Pixar Company, which had been devoted to 3D animation production for a long time and become one of the key players in the industry. This paper presents a study to discover the technical human resource in the company based on inventor analyses from patent information. Three problems were addressed as follows: (1 Pixar’s key inventors and their active periods, (2 the collaboration among these inventors, and (3 their academic achievements and professional performances and then examined their relationships among the patents, academic achievements and professional performances. In the study, we produced a graph to depict the collaboration of patent inventors when they cooperated to develop technologies and applied patents, and finally we integrated the graph with the search results from the ACM database and the IMDB databases to synthesize another graph to demonstrate the relationships among the productivities of key patent inventors in patents, academic achievements and professional performances. The findings show that in the digital content industry the performances of patent producing of technical talents principally come from the accumulation of their academic ability. When they applied the knowledge and the competence to the industry, they not only achieved remarkable success but also gained confirmation from international awards. Finally, the study also approved the potential and the feasibility of applying knowledge and techniques of bibliometrics to industrial analysis. [Article content in Chinese

  1. La motivación de logro mejora el rendimiento académico (Achievement Motivation Improves Academic Performance

    Jose Miguel Garcia-Ramirez

    2016-01-01

    Full Text Available A través de los proyectos de innovación docente las universidades mejoran y consolidan la calidad de la educación que ofrecen, tomando la creatividad y visibilidad como claves de la motivación por competencias y logro. Método: La investigación se realiza durante el curso académico 2013-14, a través del proyecto de innovación docente “ReiDoCrea” de la Universidad de Granada. Los participantes (N=62, M=22.7, SD=6.6, estudiantes de la Facultad de Ciencias del Trabajo, se adscribieron voluntariamente al Grupo Experimental (n=30 o al Grupo Control (n=32. El grupo experimental participó en el proyecto, mientras que el grupo control no participó; los instrumentos utilizados fueron dos pruebas objetivas (pre y post del programa de evaluación académica. Resultados: El análisis estadístico muestra que existen diferencias significativas entre los resultados obtenidos por el Grupo Experimental (M=83.6, SE=1.259, t(60=3.748, p<.05, d=.95 r=.43 y el Grupo Control (M=77.25, SE=1.14. Conclusiones: En la innovación docente, la motivación por competencias y de logro es clave para desarrollar el pensamiento creativo y mejorar el rendimiento académico. Abstract: Through teaching innovation projects universities improve and consolidate the quality of education they offer, taking creativity and visibility as the key to competence and achievement motivation. Method: The research study was conducted during the academic year 2013-14, through the teaching innovation project "ReiDoCrea" of the University of Granada. The participants (N=62, M=22.7, SD=6.6, students of the Faculty of Labour, voluntarily joined the Experimental Group (n=30 or the Control Group (n=32. The experimental group participated in the project, while the Control Group did not participate; the instruments used were two objective tests (pre and post, part of the academic program evaluation. Results: The statistical analysis shows that there are significant differences between the

  2. La motivación de logro mejora el rendimiento académico (Achievement Motivation Improves Academic Performance

    Jose Miguel Garcia-Ramirez

    2016-01-01

    Full Text Available A través de los proyectos de innovación docente las universidades mejoran y consolidan la calidad de la educación que ofrecen, tomando la creatividad y visibilidad como claves de la motivación por competencias y logro. Método: La investigación se realiza durante el curso académico 2013-14, a través del proyecto de innovación docente “ReiDoCrea” de la Universidad de Granada. Los participantes (N=62, M=22.7, SD=6.6, estudiantes de la Facultad de Ciencias del Trabajo, se adscribieron voluntariamente al Grupo Experimental (n=30 o al Grupo Control (n=32. El grupo experimental participó en el proyecto, mientras que el grupo control no participó; los instrumentos utilizados fueron dos pruebas objetivas (pre y post del programa de evaluación académica. Resultados: El análisis estadístico muestra que existen diferencias significativas entre los resultados obtenidos por el Grupo Experimental (M=83.6, SE=1.259, t(60=3.748, p<.05, d=.95, r=.43 y el Grupo Control (M=77.25, SE=1.14. Conclusiones: En la innovación docente, la motivación por competencias y de logro es clave para desarrollar el pensamiento creativo y mejorar el rendimiento académico. Abstract: Through teaching innovation projects universities improve and consolidate the quality of education they offer, taking creativity and visibility as the key to competence and achievement motivation. Method: The research study was conducted during the academic year 2013-14, through the teaching innovation project "ReiDoCrea" of the University of Granada. The participants (N=62, M=22.7, SD=6.6, students of the Faculty of Labour, voluntarily joined the Experimental Group (n=30 or the Control Group (n=32. The experimental group participated in the project, while the Control Group did not participate; the instruments used were two objective tests (pre and post, part of the academic program evaluation. Results: The statistical analysis shows that there are significant differences between the

  3. Evidence-based surgical training in orthopaedics: how many arthroscopies of the knee are needed to achieve consultant level performance?

    Price, A J; Erturan, G; Akhtar, K; Judge, A; Alvand, A; Rees, J L

    2015-10-01

    Despite being one of the most common orthopaedic operations, it is still not known how many arthroscopies of the knee must be performed during training in order to develop the skills required to become a Consultant. A total of 54 subjects were divided into five groups according to clinical experience: Novices (n = 10), Junior trainees (n = 10), Registrars (n = 18), Fellows (n = 10) and Consultants (n = 6). After viewing an instructional presentation, each subject performed a simple diagnostic arthroscopy of the knee on a simulator with visualisation and probing of ten anatomical landmarks. Performance was assessed using a validated global rating scale (GRS). Comparisons were made against clinical experience measured by the number of arthroscopies which had been undertaken, and ROC curve analysis was used to determine the number of procedures needed to perform at the level of the Consultants. There were marked differences between the groups. There was significant improvement in performance with increasing experience (p skills of a Consultant. We suggest that this approach to identify what represents the level of surgical skills of a Consultant should be used more widely so that standards of training are maintained through the development of an evidenced-based curriculum. PMID:26430003

  4. What Works Clearinghouse Quick Review: "Daily Online Testing in Large Classes: Boosting College Performance While Reducing Achievement

    What Works Clearinghouse, 2013

    2013-01-01

    This study investigated the effect of daily quizzes on the performance of college students. Students in an introductory psychology course used their own wireless-enabled devices to take short Internet-based quizzes at the beginning of every class. The quiz items were drawn approximately equally from material covered in the readings and the…

  5. The Influence of Parenting Styles, Achievement Motivation, and Self-Efficacy on Academic Performance in College Students

    Turner, Erlanger A.; Chandler, Megan; Heffer, Robert W.

    2009-01-01

    Parenting styles have consistently been shown to relate to various outcomes such as youth psychopathology, behavior problems, and academic performance. Building on the research in the parenting style literature, along with examining components of self-determination theory, the present study examined the relations among authoritative parenting…

  6. Valuing Information in Complex Systems: An Integrated Analytical Approach to Achieve Optimal Performance in the Beer Distribution Game

    Thompson, Kimberly M.; Badizadegan, Nima D.

    2015-01-01

    Even seemingly simple systems can produce complex dynamics, which leads management professionals to develop tools for training, monitoring, and improving performance. Management simulators provide useful insights about human behavior and interactions, while computational and informational decision support tools offer opportunities to reduce inconsistencies, errors, and non-optimal human choices, particularly for complex systems that involve multiple decision makers, uncertainty, variability, ...

  7. A Descriptive-Comparative Study of Teacher Performance Evaluation on Student Achievement in a Public School District

    Christensen, William Howard

    2013-01-01

    In 2010, the federal government increased accountability expectations by placing more emphasis on monitoring teacher performance. Using a model that focuses on the New York State teacher evaluation system, that is comprised of a rubric for observation, local student assessment scores, and student state assessment scores, this…

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

    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

  9. THE ROLE OF STRATEGY IN ACHIEVING PERFORMANCE AND INTERNATIONAL RECOGNITION – THE CASE OF ROMANIAN ADVANCED RESEARCH UNIVERSITIES

    Ruxandra CIULU; Olesia MIHAI

    2012-01-01

    The paper addresses the issue of strategy in higher education, applied to a group of top Romanian public universities. After reviewing the concepts of strategy (and its related sub-concepts), performance and internationalization, the authors briefly analyze the websites of the twelve Romanian universities included in the category ‘advanced research and education’. The study assesses the chances of Romanian universities to be included in the category of ‘top universities worldwide’ and conclu...

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

    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.

  11. The Development and Testing of Laboratory Performance Tasks for the Assessment of Achievement in High School Physics.

    Boorman, Joan Marie

    The quest to stem "the rising tide of mediocrity" described in A Nation at Risk has prompted a myriad of changes in secondary science instruction. Appropriate assessments of these changes in curriculum are crucial to a meaningful evaluation of their effectiveness. Because the nature of many of the improvements has been to engage students in higher order thinking skills, simple paper and pencil tests are often inconclusive evaluation measures. Research has shown a more definitive assessment of a student's ability to apply higher order thinking skills is possible with tests of performance in problem-solving tasks in a science laboratory. The Physics Laboratory Skills Test (PLST) was developed as a prototype assessment instrument for evaluation of student ability to perform a range of process skills in the high school physics laboratory setting. The PLST included seven different items based on topics presented in a typical high school physics course. Each item constituted a separate laboratory performance test and was completed by individual students in a 40 minute class period. A sample of 219 physics students from rural, urban, public, and private schools in NY and PA were tested with the PLST in May 1990. Results of this study show that the PLST has usability, validity, and reliability as an assessment of basic skills (measuring and reporting) and higher order skills (planning and analysis). Participating teachers determined the PLST to be an appropriate and useful tool in evaluating individual student abilities. Content validity was established via evaluation by 'expert' high school physics teachers. The Pearson Correlation Coefficient was used to verify construct validity (r =.49) and inter-rater reliability (r =.81). The Cronbach Coefficient Alpha, which was used to determine internal consistency of each item, yielded strong positive results for the PLST. The outcomes of this study will be of particular interest to curriculum developers and classroom teachers

  12. Achieving enhanced DSSC performance by microwave plasma incorporation of carbon into TiO{sub 2} photoelectrodes

    Dang, Binh H.Q.; MacElroy, Don [School of Chemical and Bioprocess Engineering, University College Dublin (Ireland); Dowling, Denis P., E-mail: denis.dowling@ucd.ie [School of Chemical and Bioprocess Engineering, University College Dublin (Ireland); School of Mechanical and Materials Engineering, University College Dublin (Ireland)

    2013-06-15

    The photoactivity of carbon-incorporated titanium dioxide (TiO{sub 2}) has been widely reported. This study involves a novel approach to the incorporation of carbon into TiO{sub 2} through the use of microwave plasma processing. The process involved thermally treating printed TiO{sub 2} nanoparticle coatings in a microwave-induced argon-oxygen plasma containing low concentrations of methane. The resulting deposited carbon layer was characterized using XRD, XPS, Raman, UV–vis, ellipsometry, and optical profilometry. It was found that the methane gas was dissociated in the microwave plasma into its carbon species, which were then deposited as a nm-thick layer onto the TiO{sub 2} coatings, most likely in the form of graphite. The photovoltaic performances of both the TiO{sub 2} and the carbon-incorporated TiO{sub 2} were assessed through J-V and IPCE measurements of the N719-sensitized solar cells using the titania as their photoanodes. Up to a 72% improvement in the maximum power density (P{sub d-max}) was observed for the carbon-incorporated TiO{sub 2} samples as compared to the TiO{sub 2}, onto which no carbon was added. This improvement was found to be mainly associated with an increase in the short-circuit current density (J{sub sc}), but independent from the open-circuit voltage (V{sub oc}), the filter factor (FF), and the level of dye adsorption. Possible contributory factors to the improved performance of the carbon-incorporated TiO{sub 2} were the enhanced electron conductivity and electron lifetime, both of which were elucidated through electrochemical impedance spectroscopy (EIS). When the surface layer was examined using XPS, the optimal carbon content on the TiO{sub 2} coating surface was found to be 8.4%, beyond which there was a reduction in the DSSC efficiency.

  13. Performance Achievement As The Impact Of Strategy Organizatonal Competence Strategy Execution And Competitive Advantage A Study On Private Polytechnics In West Java Indonesia

    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.

  14. An exact solution for the 3D MHD stagnation-point flow of a micropolar fluid

    Borrelli, A.; Giantesio, G.; Patria, M. C.

    2015-01-01

    The influence of a non-uniform external magnetic field on the steady three dimensional stagnation-point flow of a micropolar fluid over a rigid uncharged dielectric at rest is studied. The total magnetic field is parallel to the velocity at infinity. It is proved that this flow is possible only in the axisymmetric case. The governing nonlinear partial differential equations are reduced to a system of ordinary differential equations by a similarity transformation, before being solved numerically. The effects of the governing parameters on the fluid flow and on the magnetic field are illustrated graphically and discussed.

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

    Groth, Christian; Persson, Karl Gunnar

    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 and...... so do econometric studies. Applying Engels’ law, we suggest a new approach in which income growth is revealed by changes in occupational structure. Data needed for this approach are less contested than the wage and output series used in the existing literature. We find that pre-industrial Britain...

  16. Stagnation-Point Flow towards a Stretching Vertical Sheet with Slip Effects

    Khairy Zaimi

    2016-04-01

    Full Text Available The effects of partial slip on stagnation-point flow and heat transfer due to a stretching vertical sheet is investigated. Using a similarity transformation, the governing partial differential equations are reduced into a system of nonlinear ordinary differential equations. The resulting equations are solved numerically using a shooting method. The effect of slip and buoyancy parameters on the velocity, temperature, skin friction coefficient and the local Nusselt number are graphically presented and discussed. It is found that dual solutions exist in a certain range of slip and buoyancy parameters. The skin friction coefficient decreases while the Nusselt number increases as the slip parameter increases.

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

    Kimiaeifar, Amin; Bagheri, G. H.; Barari, Amin; Arabsolghar, A. R.; Rahimpour, M.

    2011-01-01

    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......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...

  18. MHD stagnation-point flow of an upper-convected Maxwell fluid over a stretching surface

    Hayat, T. [Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000 (Pakistan); Abbas, Z. [Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000 (Pakistan)], E-mail: za_qau@yahoo.com; Sajid, M. [Theoretical Plasma Physics Division, PINSTECH, P.O. Nilore, Islamabad 44000 (Pakistan)

    2009-01-30

    The present analysis comprises the steady two-dimensional magnetohydrodynamic flow of an upper-convected Maxwell fluid near a stagnation-point over a stretching surface. The governing non-linear partial differential equation for the flow are reduced to an ordinary differential equation by using similarity transformations. The analytic solution of nonlinear system is constructed in the series form using Homotopy analysis method. Convergence of the obtained series is discussed explicitly. The effects of the sundry parameters on the velocity profile is shown through graphs. The values of skin-friction coefficient for different parameters is tabulated.

  19. The major upgrade of the MAGIC telescopes, Part II: The achieved physics performance using the Crab Nebula observations

    Aleksic, J; Antonelli, L A; Antoranz, P; Babic, A; Bangale, P; Barcelo, M; Barrio, J A; Gonzalez, J Becerra; Bednarek, W; Bernardini, E; Biasuzzi, B; Biland, A; Bitossi, M; Blanch, O; Bonnefoy, S; Bonnoli, G; Borracci, F; Bretz, T; Carmona, E; Carosi, A; Cecchi, R; Colin, P; Colombo, E; Contreras, J L; Corti, D; Cortina, J; Covino, S; Da Vela, P; Dazzi, F; De Angelis, A; De Caneva, G; De Lotto, B; Wilhelmi, E de Ona; Mendez, C Delgado; Dettlaff, A; Prester, D Dominis; Dorner, D; Doro, M; Einecke, S; Eisenacher, D; Elsaesser, D; Fidalgo, D; Fink, D; Fonseca, M V; Font, L; Frantzen, K; Fruck, C; Galindo, D; Lopez, R J Garcia; Garczarczyk, M; Terrats, D Garrido; Gaug, M; Giavitto, G; Godinovic, N; Munoz, A Gonzalez; Gozzini, S R; Haberer, W; Hadasch, D; Hanabata, Y; Hayashida, M; Herrera, J; Hildebrand, D; Hose, J; Hrupec, D; Idec, W; Illa, J M; Kadenius, V; Kellermann, H; Knoetig, M L; Kodani, K; Konno, Y; Krause, J; Kubo, H; Kushida, J; La Barbera, A; Lelas, D; Lemus, J L; Lewandowska, N; Lindfors, E; Lombardi, S; Longo, F; Lopez, M; Lopez-Coto, R; Lopez-Oramas, A; Lorca, A; Lorenz, E; Lozano, I; Makariev, M; Mallot, K; Maneva, G; Mankuzhiyil, N; Mannheim, K; Maraschi, L; Marcote, B; Mariotti, M; Martinez, M; Mazin, D; Menzel, U; Miranda, J M; Mirzoyan, R; Moralejo, A; Munar-Adrover, P; Nakajima, D; Negrello, M; Neustroev, V; Niedzwiecki, A; Nilsson, K; Nishijima, K; Noda, K; Orito, R; Overkemping, A; Paiano, S; Palatiello, M; Paneque, D; Paoletti, R; Paredes, J M; Paredes-Fortuny, X; Persic, M; Poutanen, J; Moroni, P G Prada; Prandini, E; Puljak, I; Reinthal, R; Rhode, W; Ribo, M; Rico, J; Garcia, J Rodriguez; Rugamer, S; Saito, T; Saito, K; Satalecka, K; Scalzotto, V; Scapin, V; Schultz, C; Schlammer, J; Schmidl, S; Schweizer, T; Shore, S N; Sillanpaa, A; Sitarek, J; Snidaric, I; Sobczynska, D; Spanier, F; Stamerra, A; Steinbring, T; Storz, J; Strzys, M; Takalo, L; Takami, H; Tavecchio, F; Tejedor, L A; Temnikov, P; Terzic, T; Tescaro, D; Teshima, M; Thaele, J; Tibolla, O; Torres, D F; Toyama, T; Treves, A; Vogler, P; Wetteskind, H; Will, M; Zanin, R; IFAE,; UAB, Campus; Bellaterra, E-08193; Spain,; di Udine, Universita; Trieste, INFN; Udine, I-33100; Italy,; Astrophysics, INAF National Institute for; Rome, I-00136; di Siena, Universita; Pisa, INFN; Siena, I-53100; Institute, Rudjer Boskovic; Rijeka, University of; Split, University of; Zagreb, HR-10000; Croatia,; Physik, Max-Planck-Institut fur; Munchen, D-80805; Germany,; Complutense, Universidad; Madrid, E-28040; de Canarias, Inst de Astrofisica; La Laguna, E-38200; Tenerife,; Lodz, University of; Lodz, PL-90236; Poland,; Elektronen-Synchrotron, Deutsches; Zeuthen, D-15738; Zurich, ETH; Zurich, CH-8093; Switzerland,; Wurzburg, Universitat; Wurzburg, D-97074; Energeticas, Centro de Investigaciones; Tecnologicas, Medioambientales y; Sciences, Institute of Space; Barcelona, E-08193; di Padova, Universita; INFN,; Padova, I-35131; Dortmund, Technische Universitat; Dortmund, D-44221; Radiacions, Unitat de Fisica de les; de Fisica, Departament; CERES-IEEC,; de Barcelona, Universitat Autonoma; de Barcelona, Universitat; ICC,; IEEC-UB,; Barcelona, E-08028; Physics, Division of; Astronomy,; University, Kyoto; Japan,; Observatory, Tuorla; Turku, University of; Physics, Department of; Oulu, University of; Finland,; Research, Inst for Nucl; Energy, Nucl; Sofia, BG-1784; Bulgaria,; di Pisa, Universita; Pisa, I-56126; ICREA,; Insubria, Universita dell; Bicocca, INFN Milano; Como,; Como, I-22100; Observatory, European Gravitational; Macerata, I-56021 S Stefano a; Siena, INFN; at, now; :,; Center, NASA Goddard Space Flight; Greenbelt,; 20771, MD; USA,; Physics, Department of; Astronomy, Department of; Maryland, University of; Park, College; 20742, MD; de Lausanne, now at Ecole polytechnique federale; Lausanne,; Teilchenphysik, Now at Institut fur Astro- und; Innsbruck, Leopold-Franzens- Universitat; Innsbruck, A-6020; Austria,; deceased,; ESO, now at Finnish Centre for Astronomy with; Turku,; Division, now at Astrophysics Science; Centre, Bhabha Atomic Research; 400085, Mumbai; India,; INAF-Trieste, also at

    2014-01-01

    MAGIC is a system of two Imaging Atmospheric Cherenkov Telescopes located in the Canary island of La Palma, Spain. During summer 2011 and 2012 it underwent a series of upgrades, involving the exchange of the MAGIC-I camera and its trigger system, as well as the upgrade of the readout system of both telescopes. We use observations of the Crab Nebula taken at low and medium zenith angles to assess the key performance parameters of the MAGIC stereo system. For low zenith observations the trigger threshold of the MAGIC telescopes is about 50GeV. The integral sensitivity for sources with Crab Nebula-like spectrum above 220GeV is (0.66+/-0.03)% of Crab Nebula flux in 50 h of observations. The angular resolution at those energies is < 0.07 degree, while the energy resolution is 16%. We also re-evaluate the effect of the systematic uncertainty on the data taken with the MAGIC telescopes after the upgrade. We estimate that the systematic uncertainties can be divided in following components: < 15% in energy scale...

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

    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

  1. MHD Stagnation-Point Flow of Casson Fluid and Heat Transfer over a Stretching Sheet with Thermal Radiation

    Krishnendu Bhattacharyya

    2013-01-01

    Full Text Available The two-dimensional magnetohydrodynamic (MHD stagnation-point flow of electrically conducting non-Newtonian Casson fluid and heat transfer towards a stretching sheet have been considered. The effect of thermal radiation is also investigated. Implementing similarity transformations, the governing momentum, and energy equations are transformed to self-similar nonlinear ODEs and numerical computations are performed to solve those. The investigation reveals many important aspects of flow and heat transfer. If velocity ratio parameter (B and magnetic parameter (M increase, then the velocity boundary layer thickness becomes thinner. On the other hand, for Casson fluid it is found that the velocity boundary layer thickness is larger compared to that of Newtonian fluid. The magnitude of wall skin-friction coefficient reduces with Casson parameter (β. The velocity ratio parameter, Casson parameter, and magnetic parameter also have major effects on temperature distribution. The heat transfer rate is enhanced with increasing values of velocity ratio parameter. The rate of heat transfer is enhanced with increasing magnetic parameter M for B > 1 and it decreases with M for B < 1. Moreover, the presence of thermal radiation reduces temperature and thermal boundary layer thickness.

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

    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.

  3. Detection of flow separation and stagnation points using artificial hair sensors

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

    2015-11-01

    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.

  4. Study of magnetic fields and current in the Z pinch at stagnation

    Ivanov, V. V.; Anderson, A. A.; Astanovitskiy, A. L.; Nalajala, V.; Dmitriev, O. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); Papp, D. [Department of Physics, University of Nevada, Reno, Nevada 89557 (United States); ELI-ALPS, ELI-Hu Nkft., H-6720 Szeged (Hungary)

    2015-09-15

    The structure of magnetic fields in wire-array Z pinches at stagnation was studied using a Faraday rotation diagnostic at the wavelength of 266 nm. The electron plasma density and the Faraday rotation angle in plasma were calculated from images of the three-channel polarimeter. The magnetic field was reconstructed with Abel transform, and the current was estimated using a simple model. Several shots with wire-array Z pinches at 0.5–1.5 MA were analyzed. The strength of the magnetic field measured in plasma of the stagnated pinch was in the range of 1–2 MG. The magnetic field and current profile in plasma near the neck on the pinch were reconstructed, and the size of the current-carrying plasma was estimated. It was found that current flowed in the large-size trailing plasma near the dense neck. Measurements of the magnetic field near the bulge on the pinch also showed current in trailing plasma. A distribution of current in the large-size trailing plasma can prevent the formation of multi-MG fields in the Z pinch.

  5. Study of magnetic fields and current in the Z pinch at stagnation

    The structure of magnetic fields in wire-array Z pinches at stagnation was studied using a Faraday rotation diagnostic at the wavelength of 266 nm. The electron plasma density and the Faraday rotation angle in plasma were calculated from images of the three-channel polarimeter. The magnetic field was reconstructed with Abel transform, and the current was estimated using a simple model. Several shots with wire-array Z pinches at 0.5–1.5 MA were analyzed. The strength of the magnetic field measured in plasma of the stagnated pinch was in the range of 1–2 MG. The magnetic field and current profile in plasma near the neck on the pinch were reconstructed, and the size of the current-carrying plasma was estimated. It was found that current flowed in the large-size trailing plasma near the dense neck. Measurements of the magnetic field near the bulge on the pinch also showed current in trailing plasma. A distribution of current in the large-size trailing plasma can prevent the formation of multi-MG fields in the Z pinch

  6. Microfluidic-based single cell trapping using a combination of stagnation point flow and physical barrier

    Miao Yu; Zongzheng Chen; Cheng Xiang; Bo Liu; Handi Xie; Kairong Qin

    2016-01-01

    Single cell trapping in vitro by microfluidic device is an emerging approach for the study of the rela-tionship between single cells and their dynamic biochemical microenvironments. In this paper, a hydrodynamic-based microfluidic device for single cell trapping is designed using a combination of stagnation point flow and physical barrier. The microfluidic device overcomes the weakness of the tra-ditional ones, which have been only based upon either stag-nation point flows or physical barriers, and can conveniently load dynamic biochemical signals to the trapped cell. In addi-tion, it can connect with a programmable syringe pump and a microscope to constitute an integrated experimental system. It is experimentally verified that the microfluidic system can trap single cells in vitro even under flow disturbance and con-veniently load biochemical signals to the trapped cell. The designed micro-device would provide a simple yet effective experimental platform for further study of the interactions between single cells and their microenvironments.

  7. Compositional mantle layering revealed by slab stagnation at ~1000-km depth.

    Ballmer, Maxim D; Schmerr, Nicholas C; Nakagawa, Takashi; Ritsema, Jeroen

    2015-12-01

    Improved constraints on lower-mantle composition are fundamental to understand the accretion, differentiation, and thermochemical evolution of our planet. Cosmochemical arguments indicate that lower-mantle rocks may be enriched in Si relative to upper-mantle pyrolite, whereas seismic tomography images suggest whole-mantle convection and hence appear to imply efficient mantle mixing. This study reconciles cosmochemical and geophysical constraints using the stagnation of some slab segments at ~1000-km depth as the key observation. Through numerical modeling of subduction, we show that lower-mantle enrichment in intrinsically dense basaltic lithologies can render slabs neutrally buoyant in the uppermost lower mantle. Slab stagnation (at depths of ~660 and ~1000 km) and unimpeded slab sinking to great depths can coexist if the basalt fraction is ~8% higher in the lower mantle than in the upper mantle, equivalent to a lower-mantle Mg/Si of ~1.18. Global-scale geodynamic models demonstrate that such a moderate compositional gradient across the mantle can persist can in the presence of whole-mantle convection. PMID:26824060

  8. Performance-based tests versus behavioral ratings in the assessment of executive functioning in preschoolers: associations with ADHD symptoms and reading achievement.

    Miranda, Ana; Colomer, Carla; Mercader, Jessica; Fernández, M Inmaculada; Presentación, M Jesús

    2015-01-01

    The early assessment of the executive processes using ecologically valid instruments is essential for identifying deficits and planning actions to deal with possible adverse consequences. The present study has two different objectives. The first objective is to analyze the relationship between preschoolers' performance on tests of Working Memory and Inhibition and parents' and teachers' ratings of these executive functions (EFs) using the Behavior Rating Inventory of Executive Function (BRIEF). The second objective consists of studying the predictive value of the different EF measures (performance-based test and rating scales) on Inattention and Hyperactivity/Impulsivity behaviors and on indicators of word reading performance. The participants in the study were 209 children in the last year of preschool, their teachers and their families. Performance-based tests of Working Memory and Inhibition were administered, as well as word reading measures (accuracy and speed). The parents and teachers filled out rating scales of the EF and typical behaviors of attention deficit hyperactivity disorder (ADHD) symptomatology. Moderate correlation values were found between the different EF assessments procedures, although the results varied depending on the different domains. Metacognition Index from the BRIEF presented stronger correlations with verbal working memory tests than with inhibition tests. Both the rating scales and the performance-based tests were significant predictors of Inattention and Hyperactivity/Impulsivity behaviors and the reading achievement measures. However, the BRIEF explained a greater percentage of variance in the case of the ADHD symptomatology, while the performance-based tests explained reading achievement to a greater degree. The implications of the findings for research and clinical practice are discussed. PMID:25972833

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

    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.

  10. The Role of Lithium Conditioning in Achieving High Performance, Long Pulse H-mode Discharges in the NSTX and EAST Devices

    Maingi, Rajesh [PPPL; Mansfield, D. K. [PPPL; Gong, X. Z. [IPPCAS; Sun, Z. [IPPCAS; Bell, M. G. [PPPL

    2014-10-01

    In this paper, the role of lithium wall conditioning on the achievement of high performance, long pulse discharges in the National Spherical Torus Experiment (NSTX) and the Experimental Advanced Superconducting Tokamak (EAST) is documented. Common observations include recycling reduction and elimination of ELMs. In NSTX, lithium conditioning typically resulted in ELM-free operation with impurity accumulation, which was ameliorated e.g. with pulsed 3D fields to trigger controlled ELMs. Active lithium conditioning in EAST discharges has overcome this problem, producing an ELM-free Hmode with controlled density and impurities.

  11. 抑郁症肝郁气滞证及肝郁脾虚证证候标准的研究%Studies on standards for syndromes of Hepatic Qi Stagnation and Hepatic Stagnation causing Splenic Deficiency for depression

    陈珍贵; 陈泽奇; 胡随瑜; 张海男; 张宏耕

    2003-01-01

    目的探讨抑郁症肝郁气滞证、肝郁脾虚证的证候辨证标准.方法选择抑郁症临床流行病学调查肝郁气滞证588例,肝郁脾虚证487例,共1 075例,对75项证候指标进行频数分析、χ2检验等统计学处理,并建立判别方程.根据统计分析,采取主证辨证法确定两证的证候标准.结果肝郁气滞证的证候标准为:情绪抑郁、悲观厌世、善叹息、烦躁、脉弦,5项中具备3项(情绪抑郁必备),记分在4分以上者,即可诊断.肝郁脾虚证的证候标准为:情绪抑郁、悲观厌世、善叹息、倦怠乏力、纳差、形体消瘦、脉细,7项中具备4项,即肝郁两项(情绪抑郁必备),脾虚两项者,总记分在6分以上者,即可诊断.结论情绪抑郁、善叹息等5项为肝郁气滞证的证候标准,情绪抑郁、倦怠乏力、纳差等7项为肝郁脾虚证的证候标准.%Objective:To explore the standard of syndrome differentiation of the Hepatic Qi Stagnation and Hepatic Stagnation causing Splenic Deficiency for depression. Methods:588 cases with syndromes of the Hepatic Qi Stagnation and 487 cases with syndromes of the Hepatic Stagnation causing Splenic Deficiency, 1075 cases in sum,were from clinical epidemiological survery. 75 indexes were analyzed by frequency analysis and Chi-squared test. Then discriminant equations were established.According to the results of statistic analysis, by the differentiation of primary symptoms, the standard of syndrome with the Hepatic Qi Stagnation and syndrome with Hepatic Stagnation causing Splenic Deficiency for depression were developed. Results:The standard of syndrome with the Hepatic Qi Stagnation was the five symptoms including emotion depression, pessimism, sigh, dysphoria and stringy pulse.When more than three symptoms occur(emotion depression is necessary ) and the total scores are more than 4 ,the differentiation can be established. The standard of differentiation of syndrome with Hepatic Stagnation causing

  12. MHD stagnation point flow toward a linearly-stretching thermally-insulated sheet with induced magnetic field

    El-Mistikawy, Tarek M A

    2016-01-01

    The equations governing the magnetohydrodynamic stagnation point flow toward a non-conducting, thermally insulated, nonporous, linearly stretching sheet are cast in a self similar form. Consistent boundary conditions on the velocity, magnetic field and temperature are invoked. The flow problem involves three parameters- the magnetic Prandtl number, the magnetic interaction number, and the ratio of the stretching rate to the strength of the stagnation point flow. The energy equation includes viscous dissipation and Joule heating, and introduces the Prandtl number as a fourth parameter. Numerical solutions are obtained and sample results are presented.

  13. The Classroom Performance System (CPS): Effects on student participation, attendance, and achievement in multicultural anatomy and physiology classes at South Texas College

    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.

  14. Unsteady free convection of a stagnation point of attachment on an isothermal surface

    I. Pop

    1984-09-01

    Full Text Available The time development free convection flow near a three-dimensional stagnation point of attachment on an isothermal surface is studied at large Grashof numbers. A small time solution and an accurate numerical method is described for determining the solution of the time-dependent boundary-layer equations. For a range of values of parameter c, which describes the local geometry, the development of the various physical properties of the flow are calculated and compared with their values at small and large values of time. In another range of values of c the numerical results suggest the development of a singularity in the boundary-layer equations at a finite value of time. An anlysis is presented which is consistent with the numerical results and confirms the presence of this singularity.

  15. Momentum and Heat Transfer in MHD Axisymmetric Stagnation-Point Flow over a Shrinking Sheet

    T. R. Mahapatra

    2013-01-01

    Full Text Available In this paper we present a mathematical analysis for the magneto hydrodynamic (MHD axi-symmetric stagnation-point flow and heat transfer over a shrinking sheet which shrinks axi-symmetrically in its own plane. The governing partial differential equations along with the boundary conditions are first cast into a dimensionless form and then these equations are solved numerically by shooting technique. Thermal conductivity is assumed to vary linearly with the temperature. Temperature profiles are obtained for two different types of heating process namely (i the sheet with prescribed surface temperature (PST and (ii the sheet with prescribed surface heat flux (PHF. The effects of various physical parameters on the flow and heat transfer characteristics are presented graphically and discussed.

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

    Bachok, Norfifah [Department of Mathematics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Ishak, Anuar [School of Mathematical Sciences, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Pop, Ioan, E-mail: popm.ioan@yahoo.co.u [Faculty of Mathematics, University of Cluj, CP 253 (Romania)

    2010-09-06

    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.

  17. A stagnation event in the deep South Atlantic during the last interglacial period.

    Hayes, Christopher T; Martínez-García, Alfredo; Hasenfratz, Adam P; Jaccard, Samuel L; Hodell, David A; Sigman, Daniel M; Haug, Gerald H; Anderson, Robert F

    2014-12-19

    During the last interglacial period, global temperatures were ~2°C warmer than at present and sea level was 6 to 8 meters higher. Southern Ocean sediments reveal a spike in authigenic uranium 127,000 years ago, within the last interglacial, reflecting decreased oxygenation of deep water by Antarctic Bottom Water (AABW). Unlike ice age reductions in AABW, the interglacial stagnation event appears decoupled from open ocean conditions and may have resulted from coastal freshening due to mass loss from the Antarctic ice sheet. AABW reduction coincided with increased North Atlantic Deep Water (NADW) formation, and the subsequent reinvigoration in AABW coincided with reduced NADW formation. Thus, alternation of deep water formation between the Antarctic and the North Atlantic, believed to characterize ice ages, apparently also occurs in warm climates. PMID:25525246

  18. DNS of heat transfer increase in a cylinder stagnation region due to wake-induced turbulence

    Heat transfer in the stagnation point area of a heated cylinder is investigated using Direct Numerical Simulation (DNS). The heated cylinder is subjected to the turbulent wake of a smaller cylinder placed upstream. Two Reynolds numbers based on the diameter of the heated cylinder of 13,200 and 48,000 are chosen. In accordance with correlations in the literature, an increase in heat transfer compared to fully laminar flow is found for all angles along the front circumferential area of the heated cylinder. However, due to the presence of the wake, the maximum increase is shifted away from the centerline. The characteristic turbulence level and Nusselt number in the present study are an order of magnitude higher than those reported in previous simulations. The DNS results obtained, are in good agreement with an existing experimental correlation. Finally, relevant flow structures and instantaneous temperature fields are visualized.

  19. Assessment of In-Core Damage for Feeder Stagnation Break in CANDU

    Jung, Jong Yeob; Park, Joo Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-05-15

    A feeder break is a single channel accident while the other channels remain intact in the CANDU core. For some ranges of feeder break size, a flow in the channel can become stagnate due to a force balance between the upstream and the downstream ends. In the extreme, this can lead to a rapid fuel heat up and fuel damage, and the failure of a fuel channel. This break scenario is called a feeder stagnation break. Following the feeder stagnation break, the fuel and pressure tube in the affected channel heat up quickly. The channel fails due to overheating and the channel contents begin to discharge into the moderator. The discharge is composed of steam, some hydrogen produced by possible metal-water reaction, and solid fuel elements of fuel fragments with molten material. The severity of the transient is primarily determined by the amount of molten material discharged into the moderator, and by the interaction between the molten material and the moderator, which determines the rate of energy release. After a channel rupture (pressure tube and calandria tube) some SOR (Shut-Off Rod) guide tubes, which are located in the vicinity of the break in the core, may be damaged. If the damage to the guide tube is substantial, some SORs may not be able to descend into the moderator, and therefore, not contribute to the shut down of the reactor. The increase in system reactivity, due to factors such as poison dilution from discharging coolant and void formation, may challenge the reactivity worth of the available undamaged SORs. Therefore, an analysis of the reactivity worth of the partially impaired SDS 1 (Shut-Down System 1) is required to determine that it can compensate for the increase in reactivity and shut down the reactor. In this study, the hydrodynamic transient, due to the dispersed molten material and the discharged steam, was calculated following the feeder stagnation break. The timing of the channel failure and the mass of the molten material were provided from the

  20. Hydromagnetic Stagnation-Point Flow towards a Radially Stretching Convectively Heated Disk

    S. Shateyi

    2013-01-01

    Full Text Available The steady stagnation-point flow and heat transfer of an electrically conducted incompressible viscous fluid are extended to the case where the disk surface is convectively heated and radially stretching. The fluid is subjected to an external uniform magnetic field perpendicular to the plane of the disk. The governing momentum and energy balance equations give rise to nonlinear boundary value problem. Using a spectral relaxation method with a Chebyshev spectral collocation method, the numerical solutions are obtained over the entire range of the physical parameters. Emphasis has been laid to study the effects of viscous dissipation and Joule heating on the thermal boundary layer. Pertinent results on the effects of various thermophysical parameters on the velocity and temperature fields as well as local skin friction and local Nusselt number are discussed in detail and shown graphically and/or in tabular form.

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

    Hayat, T.; Muhammad, Khursheed; Farooq, M.; Alsaedi, A.

    2016-01-01

    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.

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

    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.

  3. Nonorthogonal Stagnation-point Flow of a Second-grade Fluid Past a Lubricated Surface

    Mahmood, Khalid; Sajid, Muhammad; Ali, Nasir

    2016-03-01

    The stagnation-point flow of a second-grade fluid past a power law lubricated surface is considered in this paper. It is assumed that the fluid impinges on the wall obliquely. A suitable choice of similarity transformations reduces the governing partial differential equations into ordinary differential equations. The thin lubrication layer suggests that the interface conditions between the fluid and the lubricant can be imposed on the boundary. An implicit finite difference scheme known as the Keller-Box method is employed to obtain the numerical solutions. The effects of slip parameter and Weissenberg number on the fluid velocity and streamlines is discussed in the graphs. The limiting cases of partial-slip and no-slip can be deduced from the present solutions.

  4. MHD Stagnation-Point Flow towards a Stretching Sheet with Prescribed Surface Heat Flux

    The steady two-dimensional stagnation point flow of an incompressible viscous and electrically conducting fluid, subject to a transverse uniform magnetic field, towards a stretching sheet is investigated. The governing system of partial differential equations are transformed to ordinary differential equations, which are then solved numerically using a finite difference scheme known as the Keller-box method. The effects of the governing parameters on the flow field and heat transfer characteristics are obtained and discussed. It is found that the heat transfer rate at the surface increases with the magnetic parameter when the free stream velocity exceeds the stretching velocity, for example ε>1, and the opposite is observed when ε<1. (author)

  5. Investigations of subterranean microorganisms and their importance for performance assessment of radioactive waste disposal. Results and conclusions achieved during the period 1995 to 1997

    Pedersen, K. [Goeteborg Univ. (Sweden). Dept. of General and Marine Microbiology

    1997-11-01

    In 1987, microbiology became a part of the Swedish scientific program for the safe disposal of high level nuclear waste (HLW). The goal of the microbiology sub-program is to understand how subterranean microorganisms will interact with the performance of a future HLW repository. The Swedish research program on subterranean microbiology has mainly been performed at two sites in granitic rock aquifers at depths ranging from 70 m down to 1240 m; the Stripa research mine in the middle of Sweden and the Aespoe hard rock laboratory (HRL) situated on the south eastern coast of Sweden. Some work has also been performed in co-operation with other national or international research groups in Sweden, Canada and at the natural analogue sites in Oklo in Gabon and Maqarin in Jordan. The most recent report in the SKB technical report series on microbiology and performance assessment, SKB-TR--95-10, gave the state of the art regarding microorganisms and their importance for performance assessment. That report is recommended as a source of knowledge about basic microbiology, microbial ecology of subterranean environments and the nuclear waste disposal concept in a microbiological perspective. The present report summarises results and conclusions achieved during the period 1995 to 1997 and is a continuation of SKB TR 95-10. The report is structured as summary which explains and analyses the obtained results and conclusions in a performance assessment perspective. The scientific basis for the summary is an enclosed series of eleven papers of which eight have gone through an international peer review process for publication in international scientific journals and reports and papers published earlier. 413 refs, 56 figs, 39 tabs.

  6. Investigations of subterranean microorganisms and their importance for performance assessment of radioactive waste disposal. Results and conclusions achieved during the period 1995 to 1997

    In 1987, microbiology became a part of the Swedish scientific program for the safe disposal of high level nuclear waste (HLW). The goal of the microbiology sub-program is to understand how subterranean microorganisms will interact with the performance of a future HLW repository. The Swedish research program on subterranean microbiology has mainly been performed at two sites in granitic rock aquifers at depths ranging from 70 m down to 1240 m; the Stripa research mine in the middle of Sweden and the Aespoe hard rock laboratory (HRL) situated on the south eastern coast of Sweden. Some work has also been performed in co-operation with other national or international research groups in Sweden, Canada and at the natural analogue sites in Oklo in Gabon and Maqarin in Jordan. The most recent report in the SKB technical report series on microbiology and performance assessment, SKB-TR--95-10, gave the state of the art regarding microorganisms and their importance for performance assessment. That report is recommended as a source of knowledge about basic microbiology, microbial ecology of subterranean environments and the nuclear waste disposal concept in a microbiological perspective. The present report summarises results and conclusions achieved during the period 1995 to 1997 and is a continuation of SKB TR 95-10. The report is structured as summary which explains and analyses the obtained results and conclusions in a performance assessment perspective. The scientific basis for the summary is an enclosed series of eleven papers of which eight have gone through an international peer review process for publication in international scientific journals and reports and papers published earlier

  7. Investigation on the Behavior of Austenite and Ferrite Phases at Stagnation Region in the Turning of Duplex Stainless Steel Alloys

    Nomani, J.; Pramanik, A.; Hilditch, T.; Littlefair, G.

    2016-06-01

    This paper investigates the deformation mechanisms and plastic behavior of austenite and ferrite phases in duplex stainless steel alloys 2205 and 2507 under chip formation from a machine turning operation. SEM images and EBSD phase mapping of frozen chip root samples detected a build-up of ferrite bands in the stagnation region, and between 65 and 85 pct, more ferrite was identified in the stagnation region compared to austenite. SEM images detected micro-cracks developing in the ferrite phase, indicating ferritic build-up in the stagnation region as a potential triggering mechanism to the formation of built-up edge, as transgranular micro-cracks found in the stagnation region are similar to micro-cracks initiating built-up edge formation. Higher plasticity of austenite due to softening under high strain is seen responsible for the ferrite build-up. Flow lines indicate that austenite is plastically deforming at a greater rate into the chip, while ferrite shows to partition most of the strain during deformation. The loss of annealing twins and activation of multiple slip planes triggered at high strain may explain the highly plastic behavior shown by austenite.

  8. Investigation on the Behavior of Austenite and Ferrite Phases at Stagnation Region in the Turning of Duplex Stainless Steel Alloys

    Nomani, J.; Pramanik, A.; Hilditch, T.; Littlefair, G.

    2016-04-01

    This paper investigates the deformation mechanisms and plastic behavior of austenite and ferrite phases in duplex stainless steel alloys 2205 and 2507 under chip formation from a machine turning operation. SEM images and EBSD phase mapping of frozen chip root samples detected a build-up of ferrite bands in the stagnation region, and between 65 and 85 pct, more ferrite was identified in the stagnation region compared to austenite. SEM images detected micro-cracks developing in the ferrite phase, indicating ferritic build-up in the stagnation region as a potential triggering mechanism to the formation of built-up edge, as transgranular micro-cracks found in the stagnation region are similar to micro-cracks initiating built-up edge formation. Higher plasticity of austenite due to softening under high strain is seen responsible for the ferrite build-up. Flow lines indicate that austenite is plastically deforming at a greater rate into the chip, while ferrite shows to partition most of the strain during deformation. The loss of annealing twins and activation of multiple slip planes triggered at high strain may explain the highly plastic behavior shown by austenite.

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

    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

  10. The impact of nursing students' chemistry learning performance assessment in Taiwan: competitive versus non-competitive student team achievement division approaches

    Wang, Kai-Ping

    2012-07-01

    Purpose: The purpose of this study was to determine the effectiveness of competitive Student Team Achievement Division (STAD), non-competitive STAD, and traditional learning on chemistry learning and learning perceptions. Sample, design and methods: By adopting the STAD approach, this study examined 144 nursing students at a five-year junior college in northern Taiwan during the first semester (totaling 18 weeks) of the 2008 academic year. Results: The findings reveal that both a heterogeneous group with external pressure (involving competitive STAD) and a friendship group with affective pressure (involving traditional learning) enhance group cohesion and assist students' meaningful learning; the heterogeneous group without extra pressure (involving non-competitive STAD), by contrast, fails because of apathy and lassitude. Moreover, learning effectiveness will obviously predominate until the learning strategy continues for a long period or at least one semester. Conclusions: This study revealed that the learning performance level of the competitive STAD group is significantly different from that of the non-competitive STAD group; and the learning performance level of the traditional group is significantly different from that of the non-competitive STAD group. Both the competitive STAD group and traditional group of medium ability students are significantly different from the non-competitive STAD group. Low-ability students from the competitive STAD group are significantly different from those of the non-competitive STAD, though no significant differences were found in learning perception. However, both a lack of friendship and a lack of ability in using algorithms may affect students' chemistry learning. Furthermore, gender imbalance, educational culture, and group emotions are factors that may influence student learning performance. Further study should focus on the use of grouping, improve responsibility in group discussion, and investigate group interaction

  11. Achieving highly effective non-biofouling performance for polypropylene membranes modified by UV-induced surface graft polymerization of two oppositely charged monomers.

    Zhao, Yong-Hong; Zhu, Xiao-Ying; Wee, Kin-Ho; Bai, Renbi

    2010-02-25

    A major problem in membrane technology for applications such as wastewater treatment or desalination is often the loss of membrane permeability due to biofouling initiated from protein adsorption and biofilm formation on the membrane surface. In this study, we developed a relatively simple and yet versatile approach to prepare polypropylene (PP) membrane with highly effective non-biofouling performance. Copolymer brushes were grafted to the surface of PP membrane through UV-induced polymerization of two oppositely charged monomers, i.e., [2-(methacryloyloxy)ethyl]trimethylammonium chloride (TM) and 3-sulfopropyl methacrylate potassium salt (SA), with varying TM:SA molar ratios. Surface analysis with scanning electron microscope (SEM) clearly showed the grafted copolymer brushes on the membrane surfaces and that with X-ray photoelectron spectroscope (XPS) revealed a similar TM:SA ratio of the grafted copolymer brushes to that of the monomer solution used for the polymerization. Water contact angle measurements indicated that the hydrophilicity of the membrane surfaces was remarkably improved by the grafting of the TM/SA copolymer brushes, with the lowest water contact angle of 27 degrees being achieved at the TM:SA ratio of around 1:1. Experiments for antiprotein adsorption with bovine serum album (BSA) and lysozyme (LYZ) and antibiofilm formation with Escherichia coli (E. coli) demonstrated a great dependence of the membrane performance on the TM:SA ratios of the grafted copolymer brushes. It was found that the characteristics of the surface charges of the membrane surfaces played a very important role in the non-biofouling performance, and the membrane surface with balanced positive and negative charges showed the best non-biofouling performance for the proteins and bacteria tested in this study. PMID:20121056

  12. Is yield increase sufficient to achieve food security in China?

    Wei, Xing; Zhang, Zhao; Shi, Peijun; Wang, Pin; Chen, Yi; Song, Xiao; Tao, Fulu

    2015-01-01

    Increasing demand for food, driven by unprecedented population growth and increasing consumption, will keep challenging food security in China. Although cereal yields have substantially improved during the last three decades, whether it will keep thriving to meet the increasing demand is not known yet. Thus, an integrated analysis on the trends of crop yield and cultivated area is essential to better understand current state of food security in China, especially on county scale. So far, yield stagnation has extensively dominated the main cereal-growing areas across China. Rice yield is facing the most severe stagnation that 53.9% counties tracked in the study have stagnated significantly, followed by maize (42.4%) and wheat (41.9%). As another important element for production sustainability, but often neglected is the planted area patterns. It has been further demonstrated that the loss in productive arable land for rice and wheat have dramatically increased the pressure on achieving food security. Not only a great deal of the planted areas have stagnated since 1980, but also collapsed. 48.4% and 54.4% of rice- and wheat-growing counties have lost their cropland areas to varying degrees. Besides, 27.6% and 35.8% of them have retrograded below the level of the 1980s. The combined influence (both loss in yield and area) has determined the crop sustainable production in China to be pessimistic for rice and wheat, and consequently no surprise to find that more than half of counties rank a lower level of production sustainability. Therefore, given the potential yield increase in wheat and maize, as well as substantial area loss of rice and wheat, the possible targeted adaptation measures for both yield and cropping area is required at county scale. Moreover, policies on food trade, alongside advocation of low calorie diets, reducing food loss and waste can help to enhance food security. PMID:25680193

  13. Is yield increase sufficient to achieve food security in China?

    Xing Wei

    Full Text Available Increasing demand for food, driven by unprecedented population growth and increasing consumption, will keep challenging food security in China. Although cereal yields have substantially improved during the last three decades, whether it will keep thriving to meet the increasing demand is not known yet. Thus, an integrated analysis on the trends of crop yield and cultivated area is essential to better understand current state of food security in China, especially on county scale. So far, yield stagnation has extensively dominated the main cereal-growing areas across China. Rice yield is facing the most severe stagnation that 53.9% counties tracked in the study have stagnated significantly, followed by maize (42.4% and wheat (41.9%. As another important element for production sustainability, but often neglected is the planted area patterns. It has been further demonstrated that the loss in productive arable land for rice and wheat have dramatically increased the pressure on achieving food security. Not only a great deal of the planted areas have stagnated since 1980, but also collapsed. 48.4% and 54.4% of rice- and wheat-growing counties have lost their cropland areas to varying degrees. Besides, 27.6% and 35.8% of them have retrograded below the level of the 1980s. The combined influence (both loss in yield and area has determined the crop sustainable production in China to be pessimistic for rice and wheat, and consequently no surprise to find that more than half of counties rank a lower level of production sustainability. Therefore, given the potential yield increase in wheat and maize, as well as substantial area loss of rice and wheat, the possible targeted adaptation measures for both yield and cropping area is required at county scale. Moreover, policies on food trade, alongside advocation of low calorie diets, reducing food loss and waste can help to enhance food security.

  14. An investigation of signal performance enhancements achieved through innovative pixel design across several generations of indirect detection, active matrix, flat-panel arrays

    Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and/or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 μm. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 μm pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of ∼80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 μm pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or continuous

  15. Achieving Standardization

    Henningsson, Stefan

    2016-01-01

    International e-Customs is going through a standardization process. Driven by the need to increase control in the trade process to address security challenges stemming from threats of terrorists, diseases, and counterfeit products, and to lower the administrative burdens on traders to stay...... competitive, national customs and regional economic organizations are seeking to establish a standardized solution for digital reporting of customs data. However, standardization has proven hard to achieve in the socio-technical e-Customs solution. In this chapter, the authors identify and describe what has...... to be harmonized in order for a global company to perceive e-Customs as standardized. In doing so, they contribute an explanation of the challenges associated with using a standardization mechanism for harmonizing socio-technical information systems....

  16. Achieving Standardization

    Henningsson, Stefan

    2014-01-01

    International e-Customs is going through a standardization process. Driven by the need to increase control in the trade process to address security challenges stemming from threats of terrorists, diseases, and counterfeit products, and to lower the administrative burdens on traders to stay...... competitive, national customs and regional economic organizations are seeking to establish a standardized solution for digital reporting of customs data. However, standardization has proven hard to achieve in the socio-technical e-Customs solution. In this chapter, the authors identify and describe what has...... to be harmonized in order for a global company to perceive e-Customs as standardized. In doing so, they contribute an explanation of the challenges associated with using a standardization mechanism for harmonizing socio-technical information systems....

  17. An analysis of factors correlated with the achievement of the goal standard for the science portion of the Connecticut Academic Performance Test

    Kmetz, Barbara Fotta

    2001-07-01

    This study sought to identify factors that could be used to predict the success of students on the science portion of the grade ten Connecticut Academic Performance Test (CAPT). While the Connecticut State Department of Education measures student achievement in mathematics, reading and writing in grades 4, 6, and 8, science is assessed only in the grade ten CAPT. Since the CAPT science test does not identify specific areas in need of improvement, it is not possible to determine causes for low test scores. To address this, the study investigated the predictive values of the grade eight Mastery Tests in mathematics and reading, the student ability scores of the Otis-Lennon School Ability Index, and grades in prior science courses. The research sample consisted of five hundred and twenty-five students, member of the graduating classes of 2000 and 2001 in a large suburban high school. Students in the study had participated in the district testing program and their scores for the grade seven Otis-Lennon School Ability Test (OLSAT), the grade eight Connecticut Mastery Tests (CMT) and the grade ten Connecticut Academic Performance Tests (CAPT) were available for analysis. This study investigated correlations between student achievement on the CMT and the science subtest of the CAPT, between OLSAT scores and the CAPT science scores, and between grades in ninth grade science and CAPT science scores. Scores were disaggregated by gender and by course level. Hypotheses 1, 2, 3 and 4 investigated the Pearson Product Moment Correlations of the OLSAT, CMT and course grades with scores on the science portion of the CAPT. Hypothesis 5 compared the scores of male and female students, using the t-test of independent sample means. Calculations showed moderate correlations for hypotheses 1--4, and the hypotheses were accepted. Hypothesis 5 was accepted for one class and rejected for the other. On the whole, female students received higher course grades and lower standardized test

  18. Rapid trench initiated recrystallization and stagnation in narrow Cu interconnect lines

    Understanding and ultimately controlling the self-annealing of Cu in narrow interconnect lines has remained a top priority in order to continue down-scaling of back-end of the line interconnects. Recently, it was hypothesized that a bottom-up microstructural transformation process in narrow interconnect features competes with the surface-initiated overburden transformation. Here, a set of transmission electron microscopy images which captures the grain coarsening process in 48 nm lines in a time resolved manner is presented, supporting such a process. Grain size measurements taken from these images have demonstrated that the Cu microstructural transformation in 48 nm interconnect lines stagnates after only 1.5 h at room temperature. This stubborn metastable structure remains stagnant, even after aggressive elevated temperature anneals, suggesting that a limited internal energy source such as dislocation content is driving the transformation. As indicated by the extremely low defect density found in 48 nm trenches, a rapid recrystallization process driven by annihilation of defects in the trenches appears to give way to a metastable microstructure in the trenches

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

    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 (vN ∼ 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)

  20. Obliquely-intersecting Hiemenz flows: a new interpretation of Howarth stagnation-point flows

    The interaction of two obliquely-intersecting Hiemenz planar stagnation point flows normal to a flat plate is studied. One flow of strain rate a aligned along the x-axis intersects the other of strain rate b at angle ϕ from the x-axis. Transformed to principal axes, a similarity reduction of the Navier–Stokes equation yields two ordinary differential equations with coefficients depending on the strain rate ratio σ = b/a and ϕ. These equations are then transformed into Howarth's equations via a two-parameter mapping, thereby giving an alternative interpretation of Howarth's problem. The large-σ asymptotic behavior of solutions for the limiting angles ϕ = 0° and 90° are determined. Direct numerical solutions of the principal axes equations for −1 ⩽ σ ⩽ 2 for each ϕ = 0°,15°,30°,45°,60°,75° and 90° compare precisely with those obtained from the two-parameter mapping. Plots for the wall shear stress parameters and normalized displacement thicknesses are presented along with sample similarity velocity profiles. (paper)

  1. Effects of Thermal Noise on the Transitional Dynamics of an Inextensible Elastic Filament in Stagnation Flow

    Deng, Mingge; Grinberg, Leopold; Caswell, Bruce

    2015-01-01

    We investigate the dynamics of a single inextensible elastic filament subject to anisotropic friction in a viscous stagnation-point flow, by employing both a continuum model represented by Langevin type stochastic partial differential equations (SPDEs) and a Dissipative Particle Dynamics (DPD) method. Unlike previous works1, the filament is free to rotate and the tension along the filament is determined by the local inextensible constraint. The kinematics of the filament is recorded and studied with normal modes analysis. The results show that the filament displays an instability induced by negative tension, which is analogous to Euler buckling of a beam. Symmetry breaking of normal modes dynamics and stretch-coil transitions are observed above the threshold of the buckling instability point. Furthermore, both temporal and spatial noise are amplified resulting from the interaction of thermal fluctuations and nonlinear filament dynamics. Specifically, the spatial noise is amplified with even normal modes being excited due to symmetry breaking, while the temporal noise is amplified with increasing time correlation length and variance. PMID:26023834

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

    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.

  3. Effect of wall structure on pebble stagnation behavior in pebble bed reactor

    Highlights: • DEM study of wall structure role in preventing near wall crystallization is carried out. • Suggestions on pebble’s kinematic parameters and wall structure design are provided. • Triangle is better than arc and sawtooth shapes for wall structure design. • Wall structure size should be close to the scale of pebble diameter. • Suitable intervals can prevent crystallization without significantly increasing the flow resistance. - Abstract: Crystallization of pebbles in pebble bed is a crucial problem in high temperature gas-cooled pebble-bed reactors. This phenomenon usually happens along the internal surface and leads to a large number of stagnated pebbles, which poses a threat to reactor safety. In real reactor engineering, wall structures have been utilized to avoid this problem. This article verifies the crystallization phenomenon through DEM (discrete element method) simulation, and explains how wall structures work in preventing crystallization. Moreover, several kinematic parameters have been adopted to evaluate wall structures with different shapes, sizes and intervals. Detailed information shows the impact of wall structure on flow field in pebble bed. Lastly, the preferred characteristics of an effective wall structure are suggested for reactor engineering

  4. Partial slip effect on non-aligned stagnation point nanofluid over a stretching convective surface

    Nadeem, S.; Rashid, Mehmood; Noreen Sher, Akbar

    2015-01-01

    The present study inspects the non-aligned stagnation point nano fluid over a convective surface in the presence of partial slip.Two types of base fluids namely water and kerosene are selected with Cu nanoparticles. The governing physical problem is presented and transformed into a system of coupled nonlinear differential equations using suitable similarity transformations. These equations are then solved numerically using midpoint integration scheme along with Richardson extrapolation via Maple. Impact of relevant physical parameters on the dimensionless velocity and temperature profiles are portrayed through graphs. Physical quantities such as local skin frictions co-efficient and Nusselt numbers are tabularized. It is detected from numerical computations that kerosene-based nano fluids have better heat transfer capability compared with water-based nanofluids. Moreover it is found that water-based nanofluids offer less resistance in terms of skin friction than kerosene-based fluid. In order to authenticate our present study, the calculated results are compared with the prevailing literature and a considerable agreement is perceived for the limiting case.

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

    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 Rm √(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, R0, 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)

  6. Radiation Effect on MHD Stagnation-Point Flow of a Nanofluid over an Exponentially Stretching Sheet

    Imran ANWAR

    2014-07-01

    Full Text Available This paper theoretically investigates the radiation effect on magnetohydrodynamics (MHD stagnation-point flow of a nanofluid over an exponentially stretching sheet under the assumptions of a small magnetic Reynolds number. The sheet is stretched with an exponential velocity in the presence of a non-uniform magnetic field B applied in a transverse direction normal to the flow. By using the modified Bernoulli's equation, a highly nonlinear nanofluid problem is modeled for an electrically conducting nanofluid. The momentum, thermal and concentration boundary layer thicknesses are intensified for the incorporated flow parameters such as Brownian motion parameter Nb, thermophoresis parameter Nt, Prandtl number Pr, Lewis number Le, Hartmann number Mexp and velocity ratio parameter ε. Also by an appropriate similarity transformation, the system of nonlinear partial differential equations is reduced to ordinary differential equations. These equations subjected to the boundary conditions are solved numerically using the Keller-box method. Numerical results are plotted and discussed for pertinent flow parameters. A comparison with existing results in the literature is also provided.doi:10.14456/WJST.2014.11

  7. Achieving New Source Performance Standards (NSPS) Emission Standards Through Integration of Low-NOx Burners with an Optimization Plan for Boiler Combustion

    Wayne Penrod

    2006-12-31

    The objective of this project was to demonstrate the use of an Integrated Combustion Optimization System to achieve NO{sub X} emission levels in the range of 0.15 to 0.22 lb/MMBtu while simultaneously enabling increased power output. The project plan consisted of the integration of low-NO{sub X} burners and advanced overfire air technology with various process measurement and control devices on the Holcomb Station Unit 1 boiler. The plan included the use of sophisticated neural networks or other artificial intelligence technologies and complex software to optimize several operating parameters, including NO{sub X} emissions, boiler efficiency, and CO emissions. The program was set up in three phases. In Phase I, the boiler was equipped with sensors that can be used to monitor furnace conditions and coal flow to permit improvements in boiler operation. In Phase II, the boiler was equipped with burner modifications designed to reduce NO{sub X} emissions and automated coal flow dampers to permit on-line fuel balancing. In Phase III, the boiler was to be equipped with an overfire air system to permit deep reductions in NO{sub X} emissions. Integration of the overfire air system with the improvements made in Phases I and II would permit optimization of boiler performance, output, and emissions. This report summarizes the overall results from Phases I and II of the project. A significant amount of data was collected from the combustion sensors, coal flow monitoring equipment, and other existing boiler instrumentation to monitor performance of the burner modifications and the coal flow balancing equipment.

  8. System and method for confining an object to a region of fluid flow having a stagnation point

    Schroeder, Charles M. (Inventor); Shaqfeh, Eric S. G. (Inventor); Babcock, Hazen P. (Inventor); Chu, Steven (Inventor)

    2006-01-01

    A device for confining an object to a region proximate to a fluid flow stagnation point includes one or more inlets for carrying the fluid into the region, one or more outlets for carrying the fluid out of the region, and a controller, in fluidic communication with the inlets and outlets, for adjusting the motion of the fluid to produce a stagnation point in the region, thereby confining the object to the region. Applications include, for example, prolonged observation of the object, manipulation of the object, etc. The device optionally may employ a feedback control mechanism, a sensing apparatus (e.g., for imaging), and a storage medium for storing, and a computer for analyzing and manipulating, data acquired from observing the object. The invention further provides methods of using such a device and system in a number of fields, including biology, chemistry, physics, material science, and medical science.

  9. Nonlinear convection stagnation point heat transfer and MHD fluid flow in porous medium towards a permeable shrinking sheet

    Kumar, Rakesh

    2015-01-01

    This investigation deals with the analysis of stagnation point heat transfer and corresponding flow features of hydromagnetic viscous incompressible fluid over a vertical shrinking sheet. The considered sheet is assumed to be permeable and subject to addition of stagnation point to control the generated vorticity in the boundary layer. The sheet is placed on the right side of the fluid saturated porous medium which is having permeability of specified form. Nonlinear convection waves in the flow field are realized due to the envisaged nonlinear relation between density and temperature. The equations governing the nonlinear convection boundary layer flow are modeled and simplified using similarity transformations. The economized equations are solved for numerical solutions by employing the implicit finite difference scheme also known as Keller-box method. The influence of the associated parameters of the problem on velocity and temperature distributions, skin friction and rate of heat transfer are presented thr...

  10. A uniformly valid series solution to the unsteady stagnation-point flow towards an impulsively stretching surface

    2010-01-01

    The paper studies the problem of the unsteady two-dimensional stagnation-point flow of an incompressible viscous fluid over a flat deformable sheet. The flow is started impulsively from rest and the sheet is suddenly stretched in its own plane with a velocity proportional to the distance from the stagnation point. An analytical series solution is obtained by means of the homotopy analysis method (HAM). Also, the homotopy-Pade′ technique is employed. An explicit formula for the local friction coefficient is provided. The present formula, different from the perturbation solution, is accurate and uniformly valid for all dimensionless time in the whole spatial region and for all possible values of physical parameter λ, defined as the ratio of the potential flow velocity to the sheet sudden stretching velocity. Numerical tests are done to verify the present formula for its validity and accuracy.

  11. Study the Micropolar Fluid Flow near the Stagnation on a Vertical Plate with Prescribed Wall Heat Flux

    Gitima Patowary

    2011-11-01

    Full Text Available This paper investigates the influence of the material parameter, buoyancy parameter and Prandtl number on the skin friction coefficient and the heat transfer rate at the surface on a steady, two dimensional flow of an incompressible micropolar fluid near the stagnation point on a vertical plate with prescribed surface heat flux in presence of a magnetic filed. The free stream velocity and the surface heat flux are assumed to be proportional to the distance from the stagnation point. Similarly transformation is employed to transform the governing partial differential equations to a set of ordinary differential equations. The effects of the material parameter, buoyancy parameter and Prandtl number on the skin friction coefficient and the heat transfer rate at the surface are discussed and the corresponding velocity, temperature and microrotation profiles are shown graphically. Both assisting and opposing flows are considered and it is found that dual solutions exist for both cases

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

    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.

  13. 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

    Huang Luqi

    2011-07-01

    Full Text Available Abstract 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

  14. Explorations in achievement motivation

    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.

  15. From nuclear stagnation to renaissance: The challenge of transferring regulatory knowledge

    Full text: Around 20 years ago there was a de facto nuclear stagnation of the peaceful uses of atomic energy in the West. At the time, governmental institutions for nuclear research and regulation, as well as the nuclear industry, had a nuclear 'intelligentsia' and many well qualified specialists available. Moreover, universities were ready and able to educate the next generation of professionals. The decline of the nuclear industry was therefore damaging both for individuals and the schools educating them. The options were few: for the workers, to restart a working life in other industries or to try to hang on until retirement; for the educational institutions, to abandon researching and teaching nuclear subjects. Now, however, an emerging energy crisis and growing environmental concerns about the burning of fossil fuels are inducing Western politicians to rethink the soundness of the decision to curtail the nuclear power industry. It therefore seems that there will be a nuclear renaissance, but that the qualified personnel to carry this out are no longer available, since in the intervening years they have changed jobs, retired or died. Put simply, the plentiful workforce responsible for last century's nuclear miracle is no longer there. Moreover, a cultural gap exists between the past and present generations, and such a lack of cultural continuity creates a difficult challenge for the traditional inter-generational knowledge transfer that has enabled development in the past. There are many reasons for this situation, and it will be for historians to explain them, but it is obvious that the Chernobyl accident and the public belief that nuclear installations were not safely regulated played a crucial role. At the time, nuclear regulatory authorities were less demanding, and in many countries they simply did not exist. Concepts such as regulatory independence and strengthening and safety culture are generally post-Chernobyl phenomena. Moreover, over the past decades

  16. Students' Accounts of School-Performance Stress: A Qualitative Analysis of a High-Achieving Setting in Stockholm, Sweden

    Låftman, Sara Brolin; Almquist, Ylva B.; Östberg, Viveca

    2013-01-01

    The aim of the study is to examine students' experiences of school performance as a stressor. Accounts of school-performance stress at both the individual level and in relation to group mechanisms are studied through qualitative interviews with eighth-grade students in a high-performing school in Stockholm, Sweden (n = 49). Using qualitative…

  17. Monetary Policy, Fiscal Policy, and Secular Stagnation at the Zero Lower Bound. A View on the Eurozone

    Kleczka, Mitja

    2015-01-01

    This paper delivers a contemporary estimate of the Eurozone’s natural real rate of interest. While it is found that the natural real rate has declined substantially between 1997 and 2015, it has not become negative. Thus, even in the presence of low inflation and nominal interest rates at the zero lower bound, the Eurozone does not face an acute threat of secular stagnation as defined by Lawrence Summers. Similarly, it is deemed unlikely that a number of ‘headwinds’ or a demise of technologic...

  18. Radiation effects on MHD stagnation point flow of nano fluid towards a stretching surface with convective boundary condition

    Noreen Sher Akbar; S. Nadeem; Rizwan Ul Haq; Z.H. Khan

    2013-01-01

    The aim of the present paper is to study the numerical solutions of the steady MHD two dimensional stagnation point flow of an incompressible nano fluid towards a stretching cylinder. The effects of radiation and convective boundary condition are also taken into account. The model used for the nanofluid incorporates the effects of Brownian motion and thermophoresis. The result-ing nonlinear momentum, energy and nano particle equations are simplified using similarity trans-formations. Numerical solutions have been obtained for the velocity, temperature and nanoparticle fraction profiles. The influence of physical parameters on the velocity, temperature, nanoparticle fraction, rates of heat transfer and nanoparticle fraction are shown graphically.

  19. Finite-Difference Implementation of Inviscid Separated Flows with Infinitely-Long Cusp-Ended Stagnation Zone around Circular Cylinder

    Todorov, M D

    1998-01-01

    The classical Helmholtz problem is applied for modelling and numerical investigation of inviscid cusp-ended separated flow around circular cylinder. Two coordinate systems are used: polar for initial calculations and parabolic as topologically most suited for infinite stagnation zone. Scaling by the shape of the unknown free line renders the problem to computational domain with fixed boundaries. Difference schemes and algorithm for Laplace equation and for Bernoulli integral are devised. A separated flow with drag coefficient $C_x=0$ like the so called ``critical'' flow is obtained. The pressure distribution on the surface of cylinder and the detachment point compares quantitatively very well with the predictions of the hodograph method.

  20. Autonomy Support and Achievement Goals as Predictors of Perceived School Performance and Life Satisfaction in the Transition between Lower and Upper Secondary School

    Diseth, Åge; Samdal, Oddrun

    2014-01-01

    A self-determination theory perspective on motivation assumes that basic need support is a prerequisite for motivation, achievement, and well-being in several domains of life. In the present cross-sectional study, a representative sample of 2.594 Norwegian students in their final year of lower secondary education and their first year of upper…

  1. Are Physical Activity and Academic Performance Compatible? Academic Achievement, Conduct, Physical Activity and Self-Esteem of Hong Kong Chinese Primary School Children

    Yu, C. C. W.; Chan, Scarlet; Cheng, Frances; Sung, R. Y. T.; Hau, Kit-Tai

    2006-01-01

    Education is so strongly emphasized in the Chinese culture that academic success is widely regarded as the only indicator of success, while too much physical activity is often discouraged because it drains energy and affects academic concentration. This study investigated the relations among academic achievement, self-esteem, school conduct and…

  2. High Performing Schools in High Risk Environments: A Study on Leadership, School Safety, and Student Achievement at Two Urban Middle Schools in Los Angeles County

    Frias, Gus

    2010-01-01

    In the United States of America, all students and staff have a constitutional right to attend schools that are safe, secure, and successful. Despite this right, at many public schools, education leaders have failed to ensure the safety and high academic achievement of all students. The purpose of this research study is to expand knowledge about…

  3. Feelings and Performance in the First Year at University: Learning-Related Emotions as Predictors of Achievement Outcomes in Mathematics and Statistics

    Niculescu, Alexandra C.; Templelaar, Dirk; Leppink, Jimmie; Dailey-Hebert, Amber; Segers, Mien; Gijselaers, Wim

    2015-01-01

    Introduction: This study examined the predictive value of four learning-related emotions--Enjoyment, Anxiety, Boredom and Hopelessness for achievement outcomes in the first year of study at university. Method: We used a large sample (N = 2337) of first year university students enrolled over three consecutive academic years in a mathematics and…

  4. Investigation of the Long-Term Performance of the 324 MHz Klystrons for Achieving the Efficient Operation of the Linac at J-PARC

    Hori, T.; Shinozaki, S.; Chishiro, E.; Sato, F.; Kawamura, M.; Futatsukawa, K.; Fukui, Y.; Oguri, H.

    As a part of the researches of the reliability and life time of klystrons, the cathode performance test of 324 MHz klystrons operated for 32000 hours on line has been performed at the klystron test stand. The experimental results coincide approximately with the data both reported in the literature for the cathode performance and the one obtained from the data base of RF data acquisition system. In this test, two parameters such as klystron beam perveance and knee-point were used to investigate the emission performance. It turned out that klystron beam perveance is most suitable parameter for understanding the klystron performance under operating condition on line.

  5. Unsteady stagnation-point flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet

    Naganthran, Kohilavani; Nazar, Roslinda; Pop, Ioan

    2016-04-01

    In this paper, the unsteady stagnation-point boundary layer flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet has been studied. Similarity transformation is used to transform the system of boundary layer equations which is in the form of partial differential equations into a system of ordinary differential equations. The system of similarity equations is then reduced to a system of first order differential equations and has been solved numerically by using the bvp4c function in Matlab. The numerical solutions for the skin friction coefficient and heat transfer coefficient as well as the velocity and temperature profiles are presented in the forms of tables and graphs. Dual solutions exist for both cases of stretching and shrinking sheet. Stability analysis is performed to determine which solution is stable and valid physically. Results from the stability analysis depict that the first solution (upper branch) is stable and physically realizable, while the second solution (lower branch) is unstable.

  6. Unsteady stagnation-point flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet.

    Naganthran, Kohilavani; Nazar, Roslinda; Pop, Ioan

    2016-01-01

    In this paper, the unsteady stagnation-point boundary layer flow and heat transfer of a special third grade fluid past a permeable stretching/shrinking sheet has been studied. Similarity transformation is used to transform the system of boundary layer equations which is in the form of partial differential equations into a system of ordinary differential equations. The system of similarity equations is then reduced to a system of first order differential equations and has been solved numerically by using the bvp4c function in Matlab. The numerical solutions for the skin friction coefficient and heat transfer coefficient as well as the velocity and temperature profiles are presented in the forms of tables and graphs. Dual solutions exist for both cases of stretching and shrinking sheet. Stability analysis is performed to determine which solution is stable and valid physically. Results from the stability analysis depict that the first solution (upper branch) is stable and physically realizable, while the second solution (lower branch) is unstable. PMID:27091085

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

    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.

  8. Which Feedback Is More Effective for Pursuing Multiple Goals of Differing Importance? The Interaction Effects of Goal Importance and Performance Feedback Type on Self-Regulation and Task Achievement

    Lee, Hyunjoo

    2016-01-01

    This study examined how performance feedback type (progress vs. distance) affects Korean college students' self-regulation and task achievement according to relative goal importance in the pursuit of multiple goals. For this study, 146 students participated in a computerised task. The results showed the interaction effects of goal importance and…

  9. Achieving ICME with Multiscale Modeling: The Effects of Constituent Properties and Processing on the Performance of Laminated Polymer Matrix Composite Structures

    Pineda, Evan Jorge; Bednarcyk, Brett A.; Arnold, Steven M.

    2014-01-01

    Integrated computational materials engineering (ICME) is a useful approach for tailoring the performance of a material. For fiber-reinforced composites, not only do the properties of the constituents of the composite affect the performance, but so does the architecture (or microstructure) of the constituents. The generalized method of cells is demonstrated to be a viable micromechanics tool for determining the effects of the microstructure on the performance of laminates. The micromechanics is used to predict the inputs for a macroscale model for a variety of different fiber volume fractions, and fiber architectures. Using this technique, the material performance can be tailored for specific applications by judicious selection of constituents, volume fraction, and architectural arrangement given a particular manufacturing scenario

  10. 再论"诸病兼从郁治"%Removing Stagnation as Adjuvant Treatment for All Diseases: A Further Discussion

    黄琰

    2011-01-01

    The close relationship between exogenous pathogenic factors induced diseases and stagnation syndrome was discussed based on " Huangdi’s Classic on Medicine" , " Treatise on Febrile Diseases " , and the theory of epidemic febrile diseases; and the close relationship between stagnation syndrome and miscellaneous diseases was discussed by taking hysteria, globus hystericus, dizziness, esophageal cancer, chest pain, abdominal pain, and lumbago as examples. Therefore, it is suggested that removing stagnation should be used as adjuvant treatment for all diseases.%从、及温病学说角度论述郁与外感病的密切关系,并以脏躁、梅核气、眩晕、噎膈、心腹痛、腰痛为例论述郁与内伤杂病的密切关系,从而论证了"诸病兼从郁治"的观点.

  11. Closing the social-class achievement gap: a difference-education intervention improves first-generation students' academic performance and all students' college transition.

    Stephens, Nicole M; Hamedani, MarYam G; Destin, Mesmin

    2014-04-01

    College students who do not have parents with 4-year degrees (first-generation students) earn lower grades and encounter more obstacles to success than do students who have at least one parent with a 4-year degree (continuing-generation students). In the study reported here, we tested a novel intervention designed to reduce this social-class achievement gap with a randomized controlled trial (N = 168). Using senior college students' real-life stories, we conducted a difference-education intervention with incoming students about how their diverse backgrounds can shape what they experience in college. Compared with a standard intervention that provided similar stories of college adjustment without highlighting students' different backgrounds, the difference-education intervention eliminated the social-class achievement gap by increasing first-generation students' tendency to seek out college resources (e.g., meeting with professors) and, in turn, improving their end-of-year grade point averages. The difference-education intervention also improved the college transition for all students on numerous psychosocial outcomes (e.g., mental health and engagement). PMID:24553359

  12. Single-Atom Pd₁/Graphene Catalyst Achieved by Atomic Layer Deposition: Remarkable Performance in Selective Hydrogenation of 1,3-Butadiene.

    Yan, Huan; Cheng, Hao; Yi, Hong; Lin, Yue; Yao, Tao; Wang, Chunlei; Li, Junjie; Wei, Shiqiang; Lu, Junling

    2015-08-26

    We reported that atomically dispersed Pd on graphene can be fabricated using the atomic layer deposition technique. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure spectroscopy both confirmed that isolated Pd single atoms dominantly existed on the graphene support. In selective hydrogenation of 1,3-butadiene, the single-atom Pd1/graphene catalyst showed about 100% butenes selectivity at 95% conversion at a mild reaction condition of about 50 °C, which is likely due to the changes of 1,3-butadiene adsorption mode and enhanced steric effect on the isolated Pd atoms. More importantly, excellent durability against deactivation via either aggregation of metal atoms or carbonaceous deposits during a total 100 h of reaction time on stream was achieved. Therefore, the single-atom catalysts may open up more opportunities to optimize the activity, selectivity, and durability in selective hydrogenation reactions. PMID:26268551

  13. Achieving high performance non-fullerene organic solar cells through tuning the numbers of electron deficient building blocks of molecular acceptors

    Yang, Lei; Chen, Yusheng; Chen, Shangshang; Dong, Tao; Deng, Wei; Lv, Lei; Yang, Saina; Yan, He; Huang, Hui

    2016-08-01

    Two analogous dimer and tetramer compounds, SF-PDI2 and SF-PDI4, were designed, theoretically calculated, synthesized, and developed as electron acceptors for organic solar cells. The effects of the number of the electron deficient building blocks on the optical absorption, energy levels, charge transport, morphology, crystallinity, and photovoltaic performance of the molecules were investigated. In combination with two different donors, PTB7-Th and PffBT4T-2OD, the results showed that increasing the numbers of PDI building blocks is beneficial to photovoltaic performance and leads to efficiency over 5%.

  14. The effect of parental education, prior achievement, self-efficacy, goal orientation, and effort on undergraduate science performance of Latinos and Caucasians

    Stansbury, Sydney Lynn

    Compared with majority students, underrepresented minorities have demonstrated weaker undergraduate science performance. Previous research has attributed the weaker performance to socioeconomic factors that influence poorer precollege preparation. Studies also have found that, compared with majority students, underrepresented minorities are less confident about their science skills and more interested in extrinsic rewards of science careers. Social Cognitive Theory posits that low self-efficacy coupled with high extrinsic goal orientation diminishes cognitive engagement, resulting in weak performance. Applying motivational characteristics of underrepresented minority students to a Social Cognitive Model may explain why their performance is weaker than that of Caucasians. Thus, the purpose of this study was to investigate the degree to which motivation variables account for the difference between underrepresented minority and majority students' undergraduate science performance. The study was conducted at a large, predominantly Caucasian, private university located in an urban setting in the Southwest. Two hundred twenty-two students--154 Caucasians and 68 Latinos--enrolled in a general chemistry course participated. Students were administered the Motivation for Learning Questionnaire, designed specifically for this study, consisting of scales measuring the following variables: ethnicity, level of parental education, and effort exertion; self-efficacy, effort regulation, intrinsic goal orientation, and extrinsic goal orientation, measures from the Motivated Strategies for Learning Questionnaire (Pintrich, Smith, Garcia, & McKeachie, 1991); and ability orientation, a measure from the Patterns of Adaptive Learning Survey (Midgley, Maehr, & Urdan, 1995). Financial aid information, chemistry and math placement test scores, and chemistry grades were obtained from other on-campus departments. Results demonstrated that the hypotheses were only partially confirmed by the

  15. Strategy Choice in Solving Arithmetic Word Problems: Are There Differences between Students with Learning Disabilities, G-V Poor Performance, and Typical Achievement Students?

    Gonzalez, Juan E. Jimenez; Espinel, Ana Isabel Garcia

    2002-01-01

    A study was designed to test whether there are differences between Spanish children (ages 7-9) with arithmetic learning disabilities (n=60), garden-variety (G-V) poor performance (n=44), and typical children (n=44) in strategy choice when solving arithmetic word problems. No significant differences were found between children with dyscalculia and…

  16. Are Academic Discounting and Devaluing Double-Edged Swords? Their Relations to Global Self-Esteem, Achievement Goals, and Performance among Stigmatized Students

    Loose, Florence; Regner, Isabelle; Morin, Alexandre J. S.; Dumas, Florence

    2012-01-01

    Often taken for granted, the coexistence of benefits and costs of discounting and devaluing has never been tested. Yet, not only are there inconsistent findings about the relations between these processes and global self-esteem, but little is known about their relations to motivation and performance. Here we simultaneously examined how academic…

  17. The Effect of Evaluation on Performance: Evidence from Longitudinal Student Achievement Data of Mid-Career Teachers. NBER Working Paper No. 16877

    Taylor, Eric S.; Tyler, John H.

    2011-01-01

    The effect of evaluation on employee performance is traditionally studied in the context of the principal-agent problem. Evaluation can, however, also be characterized as an investment in the evaluated employee's human capital. We study a sample of mid-career public school teachers where we can consider these two types of evaluation effect…

  18. Graded Achievement, Tested Achievement, and Validity

    Brookhart, Susan M.

    2015-01-01

    Twenty-eight studies of grades, over a century, were reviewed using the argument-based approach to validity suggested by Kane as a theoretical framework. The review draws conclusions about the meaning of graded achievement, its relation to tested achievement, and changes in the construct of graded achievement over time. "Graded…

  19. ACHIEVEMENT MOTIVATION AND ACHIEVEMENT IN ENGLISH OF HIGHER SECONDARY STUDENTS

    V.AMBEDKAR

    2012-01-01

    The world is becoming more and more competitive. Quality of performance has become the key factor for personal progress. Parents desire that their children climb the ladder of performance to as high a level as possible. This desire for a high level of achievement puts a lot of pressure on students, teachers, schools, and, in general, the educational system itself. In fact, it appears as if, the whole system of education revolves round the academic achievement of students, though various other...

  20. THE EFFECT OF PERFORMANCE ASSESSMENT APPROACH TO THE STUDENTS' LEVEL OF ACHIEVEMENT AND ATTITUDE OF THE STUDENTS FOR TEACHING SOCIAL STUDIES

    Elvan YALÇINKAYA

    2010-01-01

    The aim of this study is to investigate how the performance assessment approach effect students' academic success and attitude towards lessons at social studies lessons. The study model is designed as experimental design with pre test post test control group. The control group include 23 students, experiment group include 23 students and there are total 46 students. Economy and Social Life unit is studied with control group students by lesson book based approach and traditional assesment is ...

  1. Restaurant-bar strategic behaviors in Oulu city centre 2014: analysis of competitive advantage, performance patterns and success-achievement results

    Vera de la Rosa, Oscar Eduardo

    2014-01-01

    The objective is to measure direct and indirect competitors’ operating strategies, in order to evaluate their performance and make comparisons. The results are essential information for Coyoacán restaurant that will open on November 2014 on the street of Hallituskatu number 27. The 5 companies chosen represent the median values of all the competitors under a 93.75% certainty. The chosen “Subjects of Study” are: 1) Burgeribaari Kauppuri 5 (Bar & Grill Kauppuri 5 Oy) Fast-Food/Ba...

  2. Enhanced in Vitro and in Vivo Performance of Mg-Zn-Y-Nd Alloy Achieved with APTES Pretreatment for Drug-Eluting Vascular Stent Application.

    Liu, Jing; Zheng, Bo; Wang, Pei; Wang, Xingang; Zhang, Bin; Shi, Qiuping; Xi, Tingfei; Chen, Ming; Guan, Shaokang

    2016-07-20

    Bioabsorbable magnesium alloys are becoming prominent as temporary functional implants, as they avoid the risks generated by permanent metallic implants such as persistent inflammation and late restenosis. Nevertheless, the overfast corrosion of Mg alloys under physiological conditions hinders their wider application as medical implant materials. Here we investigate a simple one-step process to introduce a cross-linked 3-amino-propyltrimethoxysilane (APTES) silane physical barrier layer on the surface of Mg-Zn-Y-Nd alloys prior to electrostatic spraying with rapamycin-eluting poly(lactic-co-glycolic acid) (PLGA) layer. Surface microstructure was characterized by scanning electron microscope and Fourier transform infrared spectroscopy. Nanoscratch test verified the superior adhesion strength of PLGA coating in the group pretreated with APTES. Electrochemical tests combined with long-term immersion results suggested that the preferable in vitro anticorrosion behavior could be achieved by dense APTES barrier. Cell morphology and proliferation data demonstrated that APTES pretreated group resulted in remarkably preferable compatibility for both human umbilical vein endothelial cells and vascular smooth muscle cells. On the basis of excellent in vitro mechenical property, the animal study on the APTES pretreated Mg-Zn-Y-Nd stent implanted into porcine coronary arteries confirmed benign tissue compatibility as well as re-endothelialization without thrombogenesis or in-stent restenosis at six-month followup. PMID:27331417

  3. Highly Functional TNTs with Superb Photocatalytic, Optical, and Electronic Performance Achieving Record PV Efficiency of 10.1% for 1D-Based DSSCs.

    Qadir, Muhammad Bilal; Li, Yuewen; Sahito, Iftikhar Ali; Arbab, Alvira Ayoub; Sun, Kyung Chul; Mengal, Naveed; Memon, Anam Ali; Jeong, Sung Hoon

    2016-09-01

    Different nanostructures of TiO2 play an important role in the photocatalytic and photoelectronic applications. TiO2 nanotubes (TNTs) have received increasing attention for these applications due to their unique physicochemical properties. Focusing on highly functional TNTs (HF-TNTs) for photocatalytic and photoelectronic applications, this study describes the facile hydrothermal synthesis of HF-TNTs by using commercial and cheaper materials for cost-effective manufacturing. To prove the functionality and applicability, these TNTs are used as scattering structure in dye-sensitized solar cells (DSSCs). Photocatalytic, optical, Brunauer-Emmett-Teller (BET), electrochemical impedance spectrum, incident-photon-to-current efficiency, and intensity-modulated photocurrent spectroscopy/intensity-modulated photovoltage spectroscopy characterizations are proving the functionality of HF-TNTs for DSSCs. HF-TNTs show 50% higher photocatalytic degradation rate and also 68% higher dye loading ability than conventional TNTs (C-TNTs). The DSSCs having HF-TNT and its composite-based multifunctional overlayer show effective light absorption, outstanding light scattering, lower interfacial resistance, longer electron lifetime, rapid electron transfer, and improved diffusion length, and consequently, J SC , quantum efficiency, and record photoconversion efficiency of 10.1% using commercial N-719 dye is achieved, for 1D-based DSSCs. These new and highly functional TNTs will be a concrete fundamental background toward the development of more functional applications in fuel cells, dye-sensitized solar cells, Li-ion batteries, photocatalysis process, ion-exchange/adsorption process, and photoelectrochemical devices. PMID:27432775

  4. Effects of induced magnetic field and homogeneous–heterogeneous reactions on stagnation flow of a Casson fluid

    C.S.K. Raju

    2016-06-01

    Full Text Available In this study, we analyzed the induced magnetic field effect on the stagnation-point flow of a non-Newtonian fluid over a stretching sheet with homogeneous–heterogeneous reactions and non-uniform heat source or sink. The transformed ordinary differential equations are solved numerically using Runge–Kutta and Newton's method. For physical relevance we analyzed the behavior of homogeneous and heterogeneous profiles individually in the presence of induced magnetic field. The effects of different non-dimensional governing parameters on velocity, induced magnetic field, temperature and concentration profiles, along with the skin friction coefficient and local Nusselt number, are discussed and presented through graphs. The results of the present study are validated by comparing with the existed literature. Results indicate that induced magnetic field parameter and stretching ratio parameter have the tendency to enhance the heat transfer rate.

  5. MHD Stagnation-Point Flow and Heat Transfer with Effects of Viscous Dissipation, Joule Heating and Partial Velocity Slip.

    Yasin, Mohd Hafizi Mat; Ishak, Anuar; Pop, Ioan

    2015-01-01

    The steady two-dimensional stagnation-point flow and heat transfer past a permeable stretching/shrinking sheet with effects of viscous dissipation, Joule heating and partial velocity slip in the presence of a magnetic field is investigated. The partial differential equations are reduced to nonlinear ordinary differential equations by using a similarity transformation, before being solved numerically by shooting technique. Results indicate that the skin friction coefficient and the local Nusselt number increase as magnetic parameter increases. It is found that for the stretching sheet the solution is unique while for the shrinking sheet there exist nonunique solutions (dual solutions) in certain range of parameters. The stability analysis shows that the upper branch solution is stable while the lower branch solution is unstable. PMID:26647651

  6. Analytical solution to stagnation-point flow and heat transfer over a stretching sheet based on homotopy analysis

    Jing ZHU; Lian-cun ZHENG; Xin-xin ZHANG

    2009-01-01

    This paper is concerned with two-dimensional stagnation-point steady flow of an incompressible viscous fluid towards a stretching sheet whose velocity is proportional to the distance from the slit. The governing system of partial differential equations is first transformed into a system of dimensionless ordinary differential equations. Analytical solutions of the velocity distribution and dimensionless temperature profiles are obtained for different ratios of free stream velocity and stretching velocity, Prandtl number, Eckert number and dimensionality index in series forms using homotopy analysis method(HAM).It is shown that a boundary layer is formed when the free stream velocity exceeds the stretching velocity, and an inverted boundary layer is formed when the free stream velocity is less than the stretching velocity. Graphs are presented to show the effects of different parameters.

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

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

    2015-01-01

    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 is...... particularly observed for ages 15 and 50, and for that of diabetes mellitus at ages above 45 years. CONCLUSIONS: 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....

  8. Characteristics of magnetic field and melting heat transfer in stagnation point flow of Tangent-hyperbolic liquid

    Hayat, T.; Shafiq, Anum; Alsaedi, A.

    2016-05-01

    This paper examines the influence of melting heat transfer in the stagnation point flow of an incompressible magnetohydrodynamic (MHD) Tangent hyperbolic fluid. Stretched flow by a vertical surface is considered. Inclined nature of magnetic field is taken for an electrically conducting liquid. The resulting non-linear differential systems are computed for the convergent series solutions. Influences of various pertinent parameters like Weissenberg, magnetic, melting, ratio, angle of inclination, mixed convection, Eckert and Prandtl on the velocity and temperature are analyzed. Numerical data for various parameters on skin friction coefficient and local Nusselt number is also examined. It is found that the melting parameter reduces the temperature and thermal boundary layer while it shows opposite behavior for the velocity. Mixed convection has different role in the assisting and opposing flows.

  9. Stagnation point flow and heat transfer behavior of Cu-water nanofluid towards horizontal and exponentially stretching/shrinking cylinders

    Sulochana, C.; Sandeep, N.

    2016-03-01

    In this study we analyzed the stagnation point flow and heat transfer behavior of Cu-water nanofluid towards horizontal and exponentially permeable stretching/shrinking cylinders in presence of suction/injection, heat source and shape of nanoparticles. The governing boundary layer equations are transformed to nonlinear ordinary differential equations using similarity transformation which are then solved numerically using bvp4c Matlab package. The influence of non-dimensional governing parameters on the flow field and heat transfer characteristics are discussed and presented through graphs and tables. The study indicates that the solutions for the horizontal and exponential cylinders are non-unique and shape of nanoparticles also influences the rate of heat transfer. Comparisons of the present results with existed studies are presented. Present study has an excellent agreement with the existed studies under some special conditions.

  10. Line-to-line voltage based modulation scheme for single-phase reduced switch ac-dc-ac converters to achieve improved performance

    Qin, Zian; Loh, Poh Chiang; Blaabjerg, Frede

    2015-01-01

    Modulation methods can significantly influence the performance of the converter in steady state, which is therefore very important. With different objectives like the minimum current ripple, minimum power loss or maximum DC link voltage utilization, SVPWM or DPWM are normally applied. With the...... former. It thus introduces complexity to the generation of the references, especially in unbalanced source or load condition. In this paper, a line-to-line voltage based PWM reference generation method is proposed. The proposed method is easy to be implemented to maximize the DC link voltage utilization...... SVPWM or DPWM proposed in literatures, the generation of the references is phase voltage based. But the phase voltages actually cannot be controlled directly by the PWM converter, since they can be influenced by both of terminal voltages and the load network while the PWM converter can only control the...

  11. Investigation of 4H-SiC insulated-gate bipolar transistor turn-off performance for achieving low power loss

    Navarro, Dondee; Pesic, Iliya; Morikawa, Yoji; Furui, Yoshiharu; Miura-Mattausch, Mitiko

    2016-04-01

    The dynamic characteristics of a 4H-SiC insulated-gate bipolar transistor (IGBT) at pulse switching is investigated by incorporating reported measurements of the interface defect density to device simulation. Different trap features such as energy states and trap time constants are investigated to determine the influence of traps on circuit performance. The capture cross-section parameter used in the simulation depicts the probability of traps to trap/detrap carriers which relates to the carrier trap time constant. It is demonstrated that trapped carriers from the on-state condition cause enhanced generation current during the off-state condition, which give rise to undesired leakage current in addition to the threshold voltage shift previously reported. The device power dissipation is increased by a factor of 100 due to the defects.

  12. Deposition of oral bacteria and polystyrene particles to quartz and dental enamel in a parallel plate and stagnation point flow chamber

    Yang, JL; Belder, GF; Busscher, HJ; Bos, R.R.M.

    1999-01-01

    The aim of this paper is to determine to what extent (i) deposition of oral bacteria and polystyrene particles, (ii) onto quartz and dental enamel with and without a salivary conditioning film, (iii) in a parallel plate (PP) and stagnation point (SP) flow chamber and at common Peclet numbers are com

  13. Bacterial deposition to fluoridated and non-fluoridated polyurethane coatings with different elastic modulus and surface tension in a parallel plate and a stagnation point flow chamber

    Bakker, D.P.; Huijs, F.M.; Vries, J. de; Klijnstra, J.W.; Busscher, H.J.; Mei, H.C. van der

    2003-01-01

    Deposition of three marine bacterial strains with different cell surface hydrophobicities from artificial seawater to polyurethane coatings on glass with different surface tensions and elastic modulus was studied in situ in a parallel plate (PP) and stagnation point (SP) flow chamber. Different surf

  14. Bacterial deposition in a parallel plate and a stagnation point flow chamber : microbial adhesion mechanisms depend on the mass transport conditions

    Bakker, DP; Busscher, HJ; van der Mei, HC

    2002-01-01

    Deposition onto glass in a parallel plate (PP) and in a stagnation point (SP) flow chamber of Marinobacter hydrocarbonoclasticus, Psychrobacter sp. and Halomonas pacifica, suspended in artificial seawater, was compared in order to determine the influence of methodology on bacterial adhesion mechanis

  15. The Effects of Chronic Achievement Motivation and Achievement Primes on the Activation of Achievement and Fun Goals

    Hart, William; Albarracín, Dolores

    2009-01-01

    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...

  16. Achieving high performance electric field induced strain: a rational design of hyperbranched aromatic polyamide functionalized graphene-polyurethane dielectric elastomer composites.

    Chen, Tian; Qiu, Jinhao; Zhu, Kongjun; Li, Jinhuan; Wang, Jingwen; Li, Shuqin; Wang, Xiaoliang

    2015-03-26

    Dielectric elastomers have great potentials as flexible actuators in micro-electromechanical systems (MEMS) due to their large deformation, light weight, mechanical compliancy, and low cost. The low dielectric constant of these elastomers requires a rather high voltage electric field, which has greatly limited their applications. In this work, a diaphragm-type flexible microactuator comprising a hyperbranched aromatic polyamide functionalized graphene (HAPFG) filler embedded into the polyurethane (PU) dielectric elastomer matrix is described. The rational designed HAPFG sheets exhibits uniform dispersion in PU matrix and strong adhesion with the matrix by hydrogen-bond coupling. Consequently, the HAPFG-PU composites possess high dielectric performance and low loss modulus. The effect of hyperbranched aromatic polyamide functionalized graphene on high voltage electric field induced strain was experimentally investigated using the Fotonic sensor. The high electric field response of the composite was discussed by applying different kinds of alternating-current field. In addition, a comparison of the breakdown strength between the HAPFG-PU composite and the pure PU was carried out. PMID:25741878

  17. The Predictiveness of Achievement Goals

    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.

  18. Treatment Experience of Acne by the Methods of Eliminating Stagnation and Anthracoma%散结消痈治疗痤疮经验

    周宝宽; 周探

    2012-01-01

    Objective :To summarize treatment experience of acne by the. Methods of eliminating stagnation and anthracoma, and the decoctions of Miraculous decoction for regional infection, Lianqiao Baidu Powder, Wuwei Xiaodu Decoction, Simiao Yong'an decoction. Methods : Discuss principles, methods, formulas and medicinals of hypomnesia caused by sexual overindulgence based on medical records. Result: Acne with lung meridian wind-heat, toxic heat stagnanl was treated by Miraculous decoction for regional infection; acne with wind heat toxin attacking, toxic heat stagnation, qi stagnation blood stasis was treated by Lianqiao Baidu Powder; acne with lung meridian wind-heat, burn infection stagnation was treated by Wuwei Xiaodu Decoction;acne with toxic he.at flourishing and obstructing meridian and vessels was treated with Simiao Yong'an Decoction. Those methods and decoction show a better therapeutic effect on acne. Conclusions : Methods of eliminating stagnation and anthracoma have a good effect on acne.%目的:总结仙方活命饮、连翘败毒散、五味消毒饮、四妙勇安汤四方散结消痈治疗痤疮经验.方法:以医案形式,融理、法、方、药为一体进行阐述.结果:仙方活命饮加减治疗肺经风热、热毒壅滞型痤疮;连翘败毒散治疗风热毒邪上攻、热毒壅结、气血瘀滞型痤疮;五味消毒饮治疗肺经风热、火毒结聚型痤疮;四妙勇安汤治疗热毒炽盛、瘀阻经脉型痤疮,均取得满意疗效.结论:散结消痈治疗痤疮,疗效满意.

  19. The performance of small scale multi-generation technologies in achieving cost-optimal and zero-energy office building solutions

    Highlights: • The cost-optimal solutions for a new office building in Finland are obtained. • The EBPD comparative framework methodology is followed. • Biomass CHPs with high overall efficiency and low P/H ratio are economically viable. • Biomass CCHPs do not have economic or environmental benefits over biomass CHPs. • Extending the cost-optimal solutions by PV system yields NZEB with minimum LCC. - Abstract: This study investigates the economic viability of small-scale, multi-generation systems (combined heat and power (CHP), combined cooling, heating, and power (CCHP)), along with conventional heating and cooling systems combining sixteen heating/cooling energy generation systems (H/C-EGSs). The Energy Performance of Buildings Directive (EBPD) comparative framework methodology is followed. The local cost-optimal solution for an office building, in Helsinki, Finland is determined for each H/C-EGS as well as the global cost-optimum. The suggested energy efficiency measures get 144 building combinations, and alongside the H/C-EGSs, altogether 2304 cases. The results show that the global cost-optimum belongs to the ground source heat pump with free ground cooling. The investigated biomass-based CHPs are economically viable only with high overall efficiency and low power-to-heat ratio due to both low investment and operational costs. The biomass-based CCHPs do not have economic or environmental benefits over the biomass-based CHPs due to the significant increase entailed of both investment and operational costs. The fossil fuel-based CHPs with high operational costs are the worst solutions economically and environmentally. Extending the cost optimal solutions by a photovoltaic panels system yields the net zero-energy office building with minimum life-cycle costs as well

  20. Achieving extremely concentrated aqueous dispersions of graphene flakes and catalytically efficient graphene-metal nanoparticle hybrids with flavin mononucleotide as a high-performance stabilizer.

    Ayán-Varela, M; Paredes, J I; Guardia, L; Villar-Rodil, S; Munuera, J M; Díaz-González, M; Fernández-Sánchez, C; Martínez-Alonso, A; Tascón, J M D

    2015-05-20

    The stable dispersion of graphene flakes in an aqueous medium is highly desirable for the development of materials based on this two-dimensional carbon structure, but current production protocols that make use of a number of surfactants typically suffer from limitations regarding graphene concentration or the amount of surfactant required to colloidally stabilize the sheets. Here, we demonstrate that an innocuous and readily available derivative of vitamin B2, namely the sodium salt of flavin mononucleotide (FMNS), is a highly efficient dispersant in the preparation of aqueous dispersions of defect-free, few-layer graphene flakes. Most notably, graphene concentrations in water as high as ∼50 mg mL(-1) using low amounts of FMNS (FMNS/graphene mass ratios of about 0.04) could be attained, which facilitated the formation of free-standing graphene films displaying high electrical conductivity (∼52000 S m(-1)) without the need of carrying out thermal annealing or other types of post-treatment. The excellent performance of FMNS as a graphene dispersant could be attributed to the combined effect of strong adsorption on the sheets through the isoalloxazine moiety of the molecule and efficient colloidal stabilization provided by its negatively charged phosphate group. The FMNS-stabilized graphene sheets could be decorated with nanoparticles of several noble metals (Ag, Pd, and Pt), and the resulting hybrids exhibited a high catalytic activity in the reduction of nitroarenes and electroreduction of oxygen. Overall, the present results should expedite the processing and implementation of graphene in, e.g., conductive inks, composites, and hybrid materials with practical utility in a wide range of applications. PMID:25915172

  1. Hot spot formation and stagnation properties in simulations of direct-drive NIF implosions

    Schmitt, Andrew J.; Obenschain, Stephen P.

    2016-05-01

    We investigate different proposed methods of increasing the hot spot energy and radius in inertial confinement fusion implosions. In particular, shock mistiming (preferentially heating the inner edge of the target's fuel) and increasing the initial vapor gas density are investigated as possible control mechanisms. We find that only the latter is effective in substantially increasing the hot spot energy and dimensions while achieving ignition. In all cases an increase in the hot spot energy is accompanied by a decrease in the hot spot energy density (pressure) and both the yield and the gain of the target drop substantially. 2D simulations of increased vapor density targets predict an increase in the robustness of the target with respect to surface perturbations but are accompanied by significant yield degradation.

  2. Slab stagnation and buckling in the mantle transition zone: Rheology, phase transition, trench migration, and seismic structure

    Bina, Craig; Cizkova, Hana

    2014-05-01

    observations better than a flat-lying slab (Zhang et al., 2013). Earthquake hypocentral distributions and focal mechanisms may provide clearer insights into slab buckling, as they appear to vary systematically across regions of slab stagnation (Fukao and Obayashi, 2013). Stress fields computed from our dynamical models may help to illuminate such observations. References: Bina, C.R., and H. Kawakatsu, Buoyancy, bending, and seismic visibility in deep slab stagnation, Phys. Earth Planet. Inter., 183, 330-340, 2010. Čížková, H., and C.R. Bina, Effects of mantle and subduction-interface rheologies on slab stagnation and trench rollback, Earth Planet. Sci. Lett., 379, 95-103, 2013. Fukao, Y., and M. Obayashi, Deepest hypocentral distributions associated with stagnant slabs and penetrated slabs, Fall Meeting Abstracts, AGU, DI14A-01, 2013. Li, Z.-H., and N.M. Ribe, Dynamics of free subduction from 3-D boundary element modeling, J. Geophys. Res., 117, B06408. Matthews, D.C., L. Zheng, and R.G. Gordon, Do trenches advance? Fall Meeting Abstracts, AGU, T43D-2682, 2013. Zhang, Y., Y. Wang, Y. Wu, C. Bina, Z. Jin, and S. Dong, Phase transitions of harzburgite and buckled slab under eastern China, Geochem. Geophys. Geosys., 14, 1182-1199, 2013.

  3. Has Athletic Performance Reached its Peak?

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

    2015-01-01

    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 ...

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

    Ajogbeje Oke James; Borisade Fidelis Tunde; Aladesaye Charles Ademuyiwa; Ayodele Oludolapo Bolanle

    2013-01-01

    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...

  5. School Size, Achievement, and Achievement Gaps

    Bradley J. McMillen

    2004-10-01

    Full Text Available In order to examine the relationship between school size and achievement, a study was conducted using longitudinal achievement data from North Carolina for three separate cohorts of public school students (one elementary, one middle and one high school. Results revealed several interactions between size and student characteristics, all of which indicated that the achievement gaps typically existing between certain subgroups (i.e., more versus less-advantaged, lower versus higher-achieving were larger in larger schools. Results varied across the grade level cohorts and across subjects, but in general effects were more common in mathematics than in reading, and were more pronounced at the high school level. Study results are discussed in the context of educational equity and cost-effectiveness.

  6. Estimating achievement from fame

    Simkin, M. V.; Roychowdhury, V. P.

    2009-01-01

    We report a method for estimating people's achievement based on their fame. Earlier we discovered (cond-mat/0310049) that fame of fighter pilot aces (measured as number of Google hits) grows exponentially with their achievement (number of victories). We hypothesize that the same functional relation between achievement and fame holds for other professions. This allows us to estimate achievement for professions where an unquestionable and universally accepted measure of achievement does not exi...

  7. Performative

    Sack-Nielsen, Torsten

    2015-01-01

    The article describes the potential of building skins being climate-adaptive. The principle of folding, and the relation between form and performance of facades are discussed here.......The article describes the potential of building skins being climate-adaptive. The principle of folding, and the relation between form and performance of facades are discussed here....

  8. Atypical late-time singular regimes accurately diagnosed in stagnation-point-type solutions of 3D Euler flows

    Mulungye, Rachel M; Bustamante, Miguel D

    2015-01-01

    We revisit, both numerically and analytically, the finite-time blowup of the infinite-energy solution of 3D Euler equations of stagnation-point-type introduced by Gibbon et al. (1999). By employing the method of mapping to regular systems, presented in Bustamante (2011) and extended to the symmetry-plane case by Mulungye et al. (2015), we establish a curious property of this solution that was not observed in early studies: before but near singularity time, the blowup goes from a fast transient to a slower regime that is well resolved spectrally, even at mid-resolutions of $512^2.$ This late-time regime has an atypical spectrum: it is Gaussian rather than exponential in the wavenumbers. The analyticity-strip width decays to zero in a finite time, albeit so slowly that it remains well above the collocation-point scale for all simulation times $t < T^* - 10^{-9000}$, where $T^*$ is the singularity time. Reaching such a proximity to singularity time is not possible in the original temporal variable, because fl...

  9. Vorticity amplification near the stagnation point of landing gear wheels: effect of the orientation of the impinging vorticity

    Gu, Mingyao; Feltham, Graham; Ekmekci, Alis

    2014-11-01

    When oncoming streams of weak vorticity aligned with the axle axis of a two-wheel landing gear impinge near the forward stagnation point of the wheels, a mechanism for vorticity collection, growth, amplification into discrete large-scale vortices, and shedding was formerly shown to exist. In the current study, the impinging vorticity streams are perpendicular to the axle axis, i.e. in a vertical orientation as opposed to the horizontal orientation before. Experiments are conducted in a recirculating water channel using hydrogen bubble visualization and particle image velocimetry at a Reynolds number of 32,500 (based on the wheel diameter). As with the horizontal orientation, vorticity collection and amplification are observed, but the large-scale vortices thus formed are stretched around the wheel circumference in contrast to being stretched around the wheel sides, as observed for the horizontal orientation. This flow behavior varies with the impingement location of the vorticity streams across the wheel width. Maximum vorticity amplification occurs at a critical impingement location and drastically alters the flow separation along the wheel circumference. In addition, the instantaneous vortical structures are identified and tracked using a Galilean-invariant criterion.

  10. MHD Stagnation-Point Flow of a Carreau Fluid and Heat Transfer in the Presence of Convective Boundary Conditions.

    Masood Khan

    Full Text Available In the present investigation we analyze the impact of magnetic field on the stagnation-point flow of a generalized Newtonian Carreau fluid. The convective surface boundary conditions are considered to investigate the thermal boundary layer. The leading partial differential equations of the current problem are altered to a set of ordinary differential equations by picking local similarity transformations. The developed non-linear ordinary differential equations are then numerically integrated via Runge-Kutta Fehlberg method after changing into initial value problems. This investigation explores that the momentum and thermal boundary layers are significantly influenced by various pertinent parameters like the Hartmann number M, velocity shear ratio parameter α, Weissenberg number We, power law index n, Biot number γ and Prandtl number Pr. The analysis further reveals that the fluid velocity as well as the skin friction is raised by the velocity shear ratio parameter. Moreover, strong values of the Hartmann number correspond to thinning of the momentum boundary layer thickness while quite the opposite is true for the thermal boundary layer thickness. Additionally, it is seen that the numerical computations are in splendid consent with previously reported studies.

  11. MHD Stagnation-Point Flow of a Carreau Fluid and Heat Transfer in the Presence of Convective Boundary Conditions.

    Khan, Masood; Hashim; Alshomrani, Ali Saleh

    2016-01-01

    In the present investigation we analyze the impact of magnetic field on the stagnation-point flow of a generalized Newtonian Carreau fluid. The convective surface boundary conditions are considered to investigate the thermal boundary layer. The leading partial differential equations of the current problem are altered to a set of ordinary differential equations by picking local similarity transformations. The developed non-linear ordinary differential equations are then numerically integrated via Runge-Kutta Fehlberg method after changing into initial value problems. This investigation explores that the momentum and thermal boundary layers are significantly influenced by various pertinent parameters like the Hartmann number M, velocity shear ratio parameter α, Weissenberg number We, power law index n, Biot number γ and Prandtl number Pr. The analysis further reveals that the fluid velocity as well as the skin friction is raised by the velocity shear ratio parameter. Moreover, strong values of the Hartmann number correspond to thinning of the momentum boundary layer thickness while quite the opposite is true for the thermal boundary layer thickness. Additionally, it is seen that the numerical computations are in splendid consent with previously reported studies. PMID:27322600

  12. Unsteady boundary layer flow of a micro-polar fluid near the rear stagnation point of a plane surface

    Lok, Yian Yian [Academic Service Center, Kolej Universiti Teknikal Kebangsaan Malaysia, 75450 Ayer Keroh, Melaka (Malaysia); Amin, Norsarahaida [Department of Mathematics, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Pop, Ioan [Faculty of Mathematics, University of Cluj, R-3400, CP 253, Cluj (Romania)

    2003-11-01

    The growth of the boundary layer flow of a viscous and incompressible micro-polar fluid started impulsively from rest near the rear stagnation point of a two-dimensional plane surface is studied theoretically. The transformed non-similar boundary-layer equations are solved numerically using a very efficient finite-difference method known as Keller-box method. This method may present well-behaved solutions for the transient (small time) solution up to the separation boundary layer flow. Numerical results are given for the reduced velocity and micro-rotation profiles, as well as for the skin friction coefficient when the material parameter K takes the values K=0 (Newtonian fluid), 0.5, 1, 1.1, 1.5, 2, 2.5 and 3 with the boundary condition for micro-rotation n=0 (strong concentration of microelements) and n=1/2 (weak concentration of microelements), respectively. Important features of these flow characteristics are shown on graphs and in tables. (authors)

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

    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)

  14. Are the yields of major cereal crops stagnating? Results from the newly developed high spatial resolution crop yield time series

    Ray, D. K.; Ramankutty, N.; Foley, J. A.

    2011-12-01

    A variety of global scale studies that use crop yield time series for the last 50 years have remained constrained to using national level information due to the lack of high spatial resolution crop yield time series data. In this presentation we will unveil a new global crop yield data set for the 1961-2008 time period, at 5 min spatial resolution, and covering 174 crops. We developed this data by collecting national and sub-national harvested area and production information for individual crops. This new dataset can be used to answer questions related to global agriculture at a resolution and over a time period not previously possible. We have used this new dataset to address the question of whether the yields of the three important cereal crops -- maize, rice and wheat -- are stagnating as widely reported. Our results show that while in the older crop belts of the world yield improvements have slowed, a green revolution type of major yield increases in maize, rice and wheat are continuing in newly cultivated areas of the world.

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

    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)

  16. Heat Transfer due to Magnetohydrodynamic Stagnation-Point Flow of a Power-Law Fluid towards a Stretching Surface in the Presence of Thermal Radiation and Suction/Injection

    Tapas Ray Mahapatra; Sabyasachi Mondal; Dulal Pal

    2012-01-01

    An analysis is made on the study of two-dimensional MHD (magnetohydrodynamic) boundary-layer stagnation-point flow of an electrically conducting power-law fluid over a stretching surface when the surface is stretched in its own plane with a velocity proportional to the distance from the stagnation-point in the presence of thermal radiation and suction/injection. The paper examines heat transfer in the stagnation-point flow of a power-law fluid except when the ratio of the free stream velocity...

  17. Individual and social dimensions of Filipino students' achievement goals.

    Bernardo, Allan B I

    2008-10-01

    Achievement goal theory assumes that self-instrumental (mastery) achievement goals are associated with academic achievement, whereas social-instrumental (performance) goals are not. However, research on Asian students shows that both mastery and performance-approach goals are positively related to achievement; possibly because achievement motivation in Asian cultures is socially oriented and not individually oriented. The current study explored the structure of the social and individual achievement motivation orientations, and how these achievement orientations and achievement goals were related to achievement of Filipino university students. The results showed two dimensions of social-oriented achievement motivations-parent-oriented and teacher-oriented motivations-and two dimensions of individual-oriented achievement motivations-personal performance standards and personal goal choice. However, these achievement motivation orientations were not associated with achievement. Instead mastery and performance-approach goals were both positively associated with academic achievement, personal performance standards, and parent-oriented achievement motivation. PMID:22022793

  18. "The Crisis of Finance-dominated Capitalism in the Euro Area: Deficiencies in the Economic Policy Architecture and Deflationary Stagnation Policies"

    Hein, Eckhard

    2012-01-01

    In this paper the euro crisis is interpreted as the latest episode in the crisis of finance-dominated capitalism. For 11 initial Euro area countries, the major features of finance-dominated capitalism are analyzed; specifically, the increasing inequality of income distribution and the rising imbalances of current accounts. Against this background, the euro crisis and the economic policy reactions of European governments and institutions are examined. It is shown that deflationary stagnation p...

  19. Effects of Magnetic Field and Thermal Radiation on Stagnation Flow and Heat Transfer of a Power-Law Fluid over a Shrinking Sheet

    Samir Kumar Nandy

    2013-01-01

    An analysis is made on the steady two-dimensional boundary layer magnetohydrodynamic (MHD) stagnation-point flow and radiative heat transfer of an electrically conducting power-law fluid over a shrinking sheet which is shrunk in its own plane with a velocity proportional to the distance from a fixed point. The similarity transformations are used to transform the boundary layer equations into a system of nonlinear ordinary differential equations which are then solved numerically using shooting...

  20. Ant Colony Optimization Based Modified Termite Algorithm (MTA with Efficient Stagnation Avoidance Strategy for MANETs

    Sharvani G S

    2012-10-01

    Full Text Available Designing an effective load balancing algorithm is difficult due to Dynamic topology of MANET. Toaddress the problem, a load balancing routing algorithm namely Modified Termite Algorithm (MTA hasbeen developed based on ant’s food foraging behavior. Stability of the link is determined based on nodestability factor ‘’. The stability factor “ “of the node is the ratio defined between the “hello sent” and“hello replied” by a node to its neighbors. This also indicates the link stability in relation to other pathstowards the destination. A higher ratio of “” indicates that the neighbor node is more stable. Using thisconcept pheromone evaporation for the stable node is fine tuned such that if the ratio “” is more, theevaporation is slow and if “” is less the evaporation is faster. This leads to decreasing of the pheromonecontent in an optimal path which may result in congestion. These paths can be avoided using efficientevaporation technique. The MTA developed by adopting efficient pheromone evaporation technique willaddress the load balancing problems and expected to enhance the performance of the network in terms ofthroughput, and reduces End-to-end delay and Routing overheads

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

    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

  2. Achieving world class maintenance status

    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.

  3. 基于大数据技术的配电网抢修驻点优化方法%Optimization Method of Repair the Stagnation Point Distribution Based on Big Data Analysis Method

    陆如; 范宏; 周献远

    2015-01-01

    Emergency repair is an important task in the operation of distribution network,for which the scientific and efficient management and implementation method is vital to improve reliability and service quality of distribution network. A method based on Hadoop analysis method is proposed to solve the optimization problem of distribution network emergency repair stagnation points.The factors that affect the efficiency of distribution network emergency repair is analyzed comprehensively,optimization model for emergency repair stagnation point is built up,and the data mining technique for processing big data is introduced to enhance the efficiency of model analysis.In addition,the reasonable and effective allocation of emergency repair resources is achieved by quick and accurate estimation of fault time and fault point and comprehensive analysis and location of distribution network emergency repair points and states,thus improving the serve quantity and efficiency of emergency repair.%配电网故障抢修是配电网运行的重要工作,科学高效的抢修管理和实施方法对提高配电网供电可靠性和配电网服务质量意义重大.提出了基于Hadoop处理技术的大数据解决方法处理配电网抢修驻点优化问题;全面分析了影响配电网抢修效率的各个因素;建立了配电网抢修驻点优化模型;引入了处理大数据的数据挖掘技术以提高模型分析的效率.此外,通过对配电网抢修点和抢修态进行综合分析与定位,对电网故障发生时间和故障位置的准确快速判断,实现合理有效调配抢修资源,从而提高配电网故障抢修工作的服务质量和效率.

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

    A. Vrugt; F.J. Oort

    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), metacog

  5. Metacognition, Achievement Goals, Study Strategies and Academic Achievement: Pathways to Achievement

    Vrugt, Anneke; Oort, Frans J.

    2008-01-01

    The purpose of this research was to develop and test a model of effective self-regulated 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), metacognition (metacognitive knowledge, regulation and…

  6. Breathtaking or stagnation?

    Sauer, Johannes; Graversen, Jesper Tranbjerg; Park, Tim

    2006-01-01

    techniques. Finally we try to conclude on the significance of subsidies for promoting long term growth in organic production by estimating a bootstrapped bivariate probit model with respect to factors influencing the probability of organic market exit. The results revealed significant difference in the...

  7. DIDACTICS: DEVELOPMENT OR STAGNATION?

    I. P. Smirnov

    2016-01-01

    Full Text Available The aim of the paper – the detailed analysis of the monograph «Contents and Structure of Regularities of Process of Training (Theory and Experiment» which is written by the corresponding member of the Russian Academy of Education (RAE, Doctor of pedagogical sciences, Professor I. I. Logvinov. The book was included into a series «Basic researches of institute of the theory and history of pedagogics of the Russian Academy of Education. Proceedings 2008–2012».The review of the monograph of I. I. Logvinov has become a reason for reflections of the author of the present publication about actual, most burning issues of a modern Russian educational system: on the status of pedagogics in modern domestic science; evolutions of didactic knowledge and its typology; quality of dissertation researches and emasculation in scientific pedagogical concepts of the fundamental bases; ideologization of didactics and a role of the state in this process.Sorting basic thesis of I. I. Logvinov’s work, in something agreeing, and in something arguing with the scientist, the author of article claims that it is a serious and necessary work where the extremely important questions concerning the most painful points of the Russian pedagogical science and a condition of our education in general are brought up.

  8. Determinants of Student Achievement in Turkey

    Gokce Uysal; M. Alper Dincer

    2009-01-01

    Recent achievement test results show that Turkish students have been performing poorly compared to students from other countries. Using data from the PISA 2006 survey, we aim to measure the determinants of student achievement in Turkey. We find that the program type the student is enrolled in affects student achievement significantly. However, this effect may partially be biased by past academic achievement. In line with the previous literature, our results also indicate that school resources...

  9. Assessing the performance of Dutch local energy companies

    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.

  10. Hemisphericity and student achievement.

    Yeap, L L

    1989-10-01

    Hemispheric preference, the newest element of learning style, refers to the tendency of a person to use one side of the brain to perceive and function more than the other. The objective of the study was to investigate the psychological domain of learning styles in terms of the hemispheric patterns of Singapore Secondary Two students in the three achievement levels, namely Normal (low achievers), Express (average achievers), and Special (high achievers). Using the Cognitive Laterality Battery (Gordon, 1986) to measure the students' hemispheric dominance, the study found that it is in the psychological domain of the students' learning styles, in terms of their hemispheric dominance that the Secondary Two students in the three achievement levels are distinctly different. PMID:2583937

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

    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.

  12. Simultaneous Effects of MHD and Thermal Radiation on the Mixed Convection Stagnation-Point Flow of a Power-Law Fluid

    T. Hayat; M. Mustafa; S. Obaidat

    2011-01-01

    Magnetohydrodynamic (MHD) mixed convection stagnation-point flow and heat transfer of power-law fluids towards a stretching surface is investigated.The homotopy analysis method (HAM) is used in finding the series solution for a nonlinear problem.Closed form solutions for velocity and temperature fields are presented in the limiting cases.Graphical results are shown.It is found that velocity and temperature are decreasing functions of power law index.Numerical computations for shear stress coefficient and local Nusselt number are reported.The present results are also compared with the existing numerical solution in a limiting sense.

  13. College Achievement and Earnings

    Gemus, Jonathan

    2010-01-01

    I study the size and sources of the monetary return to college achievement as measured by cumulative Grade Point Average (GPA). I first present evidence that the return to achievement is large and statistically significant. I find, however, that this masks variation in the return across different groups of people. In particular, there is no relationship between GPA and earnings for graduate degree holders but a large and positive relationship for people without a graduate degree. To reconcile...

  14. Migrants and educational achievement gaps

    Entorf, Horst

    2015-01-01

    As global migration flows increase, so do the number of migrant students in host country schools. Yet migrants' achievement scores lag well behind those of their native-born schoolmates. Performance gaps are explained largely by differences in migrant parents' socio-economic background, cultural capital, and language skills. Education policy needs to focus on language teaching, parental involvement, diversity training, and beneficial social interaction between immigrant and native-born popula...

  15. Creativity, knowledge and school achievement

    Maksić Slavica B.

    2004-01-01

    Full Text Available In the process of education the knowledge is acquired which is a necessary base for creativity. The problem of relations between creativity and knowledge in school context is posed as a problem of relations between creativity and academic performance due to the influence it has on personal and professional development of an individual. The paper presents the results of survey on relations between creativity, academic performance and academic preferences. Creativity was measured by the test for creative thinking - drawing production of Urban and Jellen, academic performance by general achievement, and academic preferences by a questionnaire. The sample comprised final primary school graders. Low and statistically significant positive correlation was found between creativity and school achievement in the sub-sample of girls. However, girls have a significantly better school achievement and prefer art as a school subject and the test administered demands visual art expression. Hence, it can not be claimed for sure that the obtained results reflect realistic differences in creativity between boys and girls. It is of vital importance for work in school the data that high creativity can be possessed by students who are failures at school. It has been concluded that initial step in the acquisition of knowledge that will contribute to student creative thinking and behavior is the development of cognitive flexibility.

  16. Method for exciting a gas dynamic CO/sub 2/ laser at high stagnation temperatures and apparatus for practical application. Verfahren zum Anregen eines gasdynamischen CO/sub 2/-Lasers bei hohen Stagnationstemperaturen und Anordnung zur Durchfuehrung des Verfahrens

    Born, G.; Hermansdorfer, H.; Sepp, G.; Grosch, G.

    1981-03-26

    A method for exciting a gas dynamic CO/sub 2/ laser, especially at high stagnation temperatures above 2500 K and at a combustion chamber pressure above 50 bar, is described. A liquid fuel (e.g. C/sub 6/H/sub 6/, C/sub 2/N/sub 2/, C/sub 7/H/sub 5/N, C/sub 5/H/sub 5/N) and a liquid oxidizer (e.g. N/sub 2/O, NO, N/sub 2/O/sub 4/) are injected into the combustion chamber at these operating parameters and the produced laser gas is caused to flow through a Laval nozzle into a resonator. The flow cross sectional area of the Laval nozzle adjacent to the resonator is at least 100 times larger than the flow cross sectional area adjacent to the nozzle neck facing the combustion chamber. The flow of the laser gas through this nozzle cools the gas to about 300 K, whereby an inversion state is produced. The laser for performing this type of operation has a combustion chamber connected through the above mentioned nozzle to a resonator which in turn is connected to a diffuser. A tank for liquid fuel and a tank for a liquid oxidizer are connected to the respective injection nozzles of the combustion chamber, whereby the respective conduits preferably extend through cooling jackets of the combustion chamber of the diffuser.

  17. Performance assessment of a cavity ring-down laser spectrometer: achieving better precision and accuracy in the measurement of δ18O and δ2H in liquid water samples

    The development of new isotopic laser-based analyzers currently represents a clear alternative to conventional isotope ratio mass spectrometers. However, this analytical technique also suffers some disadvantages such as the memory effect, problems related to the overall stability of the equipment and other issues associated with the injection system, essentially regarding the syringe's longevity. This paper aims to minimize these disadvantages in order to increase the overall performance, in terms of precision and accuracy, of these kinds of analyzers. The main results of the experiments carried out in this paper have shown that: (i) the minimum number of discarded injections needed to eliminate the memory effect can be determined just considering the expected isotopic signature difference between two consecutive samples; (ii) both accuracy and precision of the isotopic measurements increase with increasing injection volume up to 2.1–2.2 µL; (iii) it is possible to extend the syringe lifetime by almost a factor of 6 by using n-methyl 2-pyrrolidone as a lubricant. Besides, it has been concluded that, by using the appropriate procedure, the main disadvantages associated with CRDS laser spectroscopy analyzers can be minimized, achieving measurement accuracy and precision of the order of ±0.05 ‰ for δ18O and ±0.3 ‰ for δ2H. (paper)

  18. Two Quality of Higher Vocational College Graduates.Academic Achievement and Workplace Performance%高职院校毕业生的两种质量:学业成就以及职场表现

    庄西真

    2012-01-01

    According to the view of the higher occupation education is a kind of training skilled personnel educa- tion, the lack of skilled talents and the higher occupation education expansion between contrast analysis, this arti- cle put forward the skill talent has its own development law of conclusion. On this basis, the article according to the higher occupation college graduates' dual identity judgment, then put forward the higher occupation college graduates' academic achievement and job performance of two kinds of quality.%根据高等职业教育是一种培养技能型人才的教育的普遍观点,通过技能型人才短缺和高等职业教育规模扩张之间反差的分析,提出技能型人才有自己的成长规律的结论。在此基础上,根据高等职业院校毕业生的双重身份特点,提出高等职业院校毕业生有学业成就和职场表现两种质量的结论。

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

    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)

  20. Three-dimensional magnetohydrodynamics axisymmetric stagnation flow and heat transfer due to an axisymmetric shrinking/stretching sheet with viscous dissipation and heat source/sink

    The present work is concerned with the effects of viscous dissipation and heat source/sink on a three-dimensional magnetohydrodynamic boundary layer axisymmetric stagnation flow, and the heat transfer of an electrically conducting fluid over a sheet, which shrinks or stretches axisymmetrically in its own plane where the line of the symmetry of the stagnation flow and that of the shrinking (stretching) sheet are, in general, not aligned. The governing equations are transformed into ordinary differential equations by using suitable similarity transformations and then solved numerically by a shooting technique. This investigation explores the conditions of the non-existence, existence and uniqueness of the solutions of the similar equations numerically. It is noted that the range of the velocity ratio parameter, where the similarity solution exists, is increased with the increase of the value of the magnetic parameter. Furthermore, the study reveals that the non-alignment function affects the shrinking sheet more than the stretching sheet. In addition, the numerical results of the velocity profile, temperature profile, skin-friction coefficient, and rate of heat transfer at the sheet are discussed in detail with different parameters. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  1. Personality and academic achievement in nniversity students

    Isabel Niño de Guzmán

    2003-06-01

    Full Text Available The correlations among personality, academic performance and other variables in 170 university students were studied, using two instruments validated into the population: the NEOPJ-R, and the EPPS. Other variables as age, study level, self perception of academic achievement and self perception of motivation, and sources of support were included. Jt was confirmed the reliability and validity of both tests and the correlations between them. The results showed associations among academic performance and conscientiousness, endurance,change, and aggression. The academic performance was better explained by achievements triving, deliberation, change, self perception of academic achievement and age.

  2. Can the Academic Achievement of Korean Students Be Portrayed as a Product of "Shadow Achievement"?

    Kim, Hyunjin

    2015-01-01

    The purpose of this study was to investigate the effects of private tutoring expenditure on two types of Korean students' academic achievements as measured by standardized test achievement and by school performance achievement, applying 5-year data from Korean Educational Longitudinal Study (KELS). It was found that private tutoring…

  3. Setting and Achieving Objectives.

    Knoop, Robert

    1986-01-01

    Provides basic guidelines which school officials and school boards may find helpful in negotiating, establishing, and managing objectives. Discusses characteristics of good objectives, specific and directional objectives, multiple objectives, participation in setting objectives, feedback on goal process and achievement, and managing a school…

  4. Intelligence and Educational Achievement

    Deary, Ian J.; Strand, Steve; Smith, Pauline; Fernandes, Cres

    2007-01-01

    This 5-year prospective longitudinal study of 70,000+ English children examined the association between psychometric intelligence at age 11 years and educational achievement in national examinations in 25 academic subjects at age 16. The correlation between a latent intelligence trait (Spearman's "g"from CAT2E) and a latent trait of educational…

  5. Achievement Goals, Learning Strategies and Language Achievement among Peruvian High School Students

    Lennia Matos

    2007-05-01

    Full Text Available We used an achievement goal framework to study the role of motivation in the academic context of a Peruvian sample of 8th to 10th grade high school students (N = 1505. The purpose of this cross-sectional study was to examine the relationship between students' achievement goals, their use of learning strategies and their academic achievement. Multiple Hierarchical Regressions Analyses identified, as predicted, positive effects of mastery goals, including more use of learning strategies and higher academic achievement, and negative effects of performance avoidance goals, including lower academic achievement. Mixed results were found for pursuing performance approach goals, which predicted a greater use of learning strategies, but were unrelated to academic achievement. The present findings support the external validity of achievement goal theory in a sample of students from a culture that is understudied in the achievement goal literature in particular and the motivational literature in general.

  6. Teaching for Successful Intelligence Raises School Achievement.

    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…

  7. ACHIEVING OPTIMAL SCHOOL CLIMATE

    Nizar SHIHADI

    2015-01-01

    Development of optimal school climate is the basis of educational, social and moral work in school. Optimal educa-tional climate in a school is a condition for learning and development of all those attending the educational establishment (pupils, teachers and parents). The school is responsible for the personal, cognitive, emotional, social and moral develop-ment of pupils. The educational team has the ability and commitment to promote an educational climate. Improvement of study achievements...

  8. Motivation and achievements

    Stefanova, Sladzana; Miceski, Trajko

    2015-01-01

    Motivation of employees as management function is an important factor in encouraging, guiding and strengthening the behavior of employees in organizations. For one organization is very important the employees to be motivated, only thus will be achieved its objectives. The manager is usually responsible for the motivation of employees and for fulfilment their needs in the workplace, but it is recommended the employees to motivate themselves. Generally, employees are working t...

  9. A 2 X 2 achievement goal framework.

    Elliot, A J; McGregor, H A

    2001-03-01

    A 2 x 2 achievement goal framework comprising mastery-approach, mastery-avoidance, performance-approach, and performance-avoidance goals was proposed and tested in 3 studies. Factor analytic results supported the independence of the 4 achievement goal constructs. The goals were examined with respect to several important antecedents (e.g., motive dispositions, implicit theories, socialization histories) and consequences (e.g., anticipatory test anxiety, exam performance, health center visits), with particular attention allocated to the new mastery-avoidance goal construct. The results revealed distinct empirical profiles for each of the achievement goals; the pattern for mastery-avoidance goals was, as anticipated, more negative than that for mastery-approach goals and more positive than that for performance-avoidance goals. Implications of the present work for future theoretical development in the achievement goal literature are discussed. PMID:11300582

  10. Identifying learning techniques among high achievers

    Shanmukananda P; L. Padma

    2013-01-01

    Background: In every college, it is noticed that in spite of being exposed to the same teaching modalities and adopting seemingly similar strategies, some students perform much better than their peers. This can be evaluated in the form of better academic performance in the internal assessments they undertake. This project is an endeavor to identify the learning techniques among high achievers which they employ to outperform others. We can also suggest the same to the medium and low achievers ...

  11. Achieving customer choice

    The Association of Major Power Consumers in Ontario (AMPCO) is composed of 66 members representing the largest industrial consumers of electricity in Ontario. AMPCO's goal is to achieve competitive rates and a reliable supply of electricity in the province. This paper explains AMPCO's minimum conditions that customers should expect in Ontario's new restructured electricity marketplace. A review of the White Paper and what AMPCO considers to be its major weaknesses, namely the creation of one single giant generating company, (Genco), problems regarding stranded debt, market regulation, and increased volatility in the marketplace are also addressed

  12. Sleep and Student Achievement

    Eric R Eide; Mark H. Showalter

    2012-01-01

    We explore the relationship between sleep and student performance on standardized tests. We model test scores as a nonlinear function of sleep, which allows us to compute the hours of sleep associated with maximum test scores. We refer to this as “optimal” hours of sleep. We also evaluate how the sleep and student performance relationship changes with age. We use the Panel Study of Income Dynamics-Child Development Supplement, which includes excellent control variables that are not usually av...

  13. Achieving empowerment through information.

    Parmalee, J C; Scholomiti, T O; Whitman, P; Sees, M; Smith, D; Gardner, E; Bastian, C

    1993-05-01

    Despite the problems we encountered, which are not uncommon with the development and implementation of any data system, we are confident that our success in achieving our goals is due to the following: establishing a reliable information database connecting several related departments; interfacing with registration and billing systems to avoid duplication of data and chance for error; appointing a qualified Systems Manager devoted to the project; developing superusers to include intensive training in the operating system (UNIX), parameters of the information system, and the report writer. We achieved what we set out to accomplish: the development of a reliable database and reports on which to base a variety of hospital decisions; improved hospital utilization; reliable clinical data for reimbursement, quality management, and credentialing; enhanced communication and collaboration among departments; and an increased profile of the departments and staff. Data quality specialists, Utilization Management and Quality Management coordinators, and the Medical Staff Credentialing Supervisor and their managers are relied upon by physicians and administrators to provide timely information. The staff are recognized for their knowledge and expertise in their department-specific information. The most significant reward is the potential for innovation. Users are no longer restricted to narrow information corridors. UNIX programming encourages creativity without demanding a degree in computer science. The capability to reach and use diverse hospital database information is no longer a dream. PMID:10139109

  14. Slip Effect on an Unsteady MHD Stagnation-Point Flow of a Micropolar Fluid towards a Shrinking Sheet with Thermophoresis Effect

    Zaib, Aurang; Shafie, Sharidan

    2015-09-01

    The effect of slip and thermophoresis on an unsteady magnetohydrodynamic stagnation-point-flow micropolar fluid with heat and mass transfer towards a shrinking sheet has been investigated. The governing equations are reduced to a system of non-dimensional partial differential equations by using similarity transformation, before being solved numerically using the Keller-box method. The effects of various physical parameters on the velocity, microrotation, temperature, and concentration profiles as well as the reduced skin friction, the reduced Nusselt number, and the reduced Sherwood number are analyzed and discussed graphically. It is found that the concentration boundary layer thickness decreases with increasing values of the thermophoresis. Comparison with previously published results under the limiting cases is made and found to be in excellent agreement.

  15. Unsteady MHD stagnation-point flow with heat and mass transfer in a micropolar fluid in the presence of thermophoresis and suction/injection

    The effect of suction or injection on unsteady MHD flow with heat and mass transfer in a micropolar fluid near the forward stagnation point flow with thermophoresis has been investigated. The problem is reduced to a system of non-dimensional partial differential equations, which are solved numerically using the implicit finite-difference scheme. Profiles for velocity, microrotation, temperature and concentration as well as the skin friction, the rate of heat and mass transfer are determined and presented graphically for physical parameters. The results show that the suction increases the skin friction, the rate of heat and mass transfer while opposite trend is observed for the case of injection. It is also found that the effect of thermophoresis is decrease the concentration boundary layer thickness. (author)

  16. MHD Boundary Layer Flow near Stagnation Point of Linear Stretching Sheet with Variable Thermal Conductivity via He’s Homotopy Perturbation Method

    JHANKAL ANUJ

    2015-01-01

    Full Text Available MHD boundary layer flow near stagnation point of linear stretching sheet with variable thermal conductivity are solved using He’s Homotopy Perturbation Method (HPM, which is one of the semi-exact method. Similarity transformation has been used to reduce the governing differential equations into an ordinary non-linear differential equation. The main advantage of HPM is that it does not require the small parameter in the equations and hence the limitations of traditional perturbations can be eliminated. In this paper firstly, the basic idea of the HPM for solving nonlinear differential equations is briefly introduced and then it is employed to derive solution of nonlinear governing equations of MHD boundary layer flow with nonlinear term. The influence of various relevant physical characteristics are presented and discussed.

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

    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 (FT4), 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 FT4 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)

  18. Lie Group Analysis and Similarity Solutions for Mixed Convection Boundary Layers in the Stagnation-Point Flow toward a Stretching Vertical Sheet

    Sarkhosh Seddighi Chaharborj

    2013-01-01

    Full Text Available An analysis for the mixed convection boundary layers in the stagnation-point flow toward a stretching vertical sheet is carried out via symmetry analysis. By employing Lie group method to the given system of nonlinear partial differential equations, we can obtain information about the invariants and symmetries of these equations. This information can be used to determine the similarity variables that will reduce the number of independent variables in the system. The transformed ordinary differential equations are solved numerically for some values of the parameters involved using fifth-order Improved Runge-Kutta Method (IRK5 coupled with shooting method. The features of the flow and heat transfer characteristics are analyzed and discussed in detail. Both cases of assisting and opposing flows are considered. This paper' results in comparison with known results are excellent.

  19. [The Colombian healthcare system: 20 years of achievements and problems].

    Calderón, Carlos Alberto Agudelo; Botero, Jaime Cardona; Bolaños, Jesús Ortega; Martínez, Rocio Robledo

    2011-06-01

    An overview of some of the key processes and results of Colombia's National Health System is presented. A systematic review of the literature evaluating the quality of the evidence published in indexed journals and literature not published in journals was made. Health system financial resources have seen a sustained increase while spending on health has remained at around 8% of GNP. Coverage, measured by affiliation to contributory and subsidized regimes, is in the order of 92% of the total population. The Mandatory Health Plan, defining the benefits to which one has access, has been broadly maintained but has been hampered by mechanisms for making legal complaints, thereby leading to financial deficits. The health system has contributed towards improving the poorest sector's income, but inequalities persist due to the lack of universal coverage, differences in health plans and the system's expenditure according to the population's income. Advances made in the National Health System have been positive but universality has not been achieved and this has stagnated in matters regarding access to services and equality. PMID:21709979

  20. Spatially resolved X-ray emission measurements of the residual velocity during the stagnation phase of inertial confinement fusion implosion experiments

    Ruby, J. J.; Pak, A.; Field, J. E.; Ma, T.; Spears, B. K.; Benedetti, L. R.; Bradley, D. K.; Berzak Hopkins, L. F.; Casey, D. T.; Döppner, T.; Eder, D.; Fittinghoff, D.; Grim, G.; Hatarik, R.; Hinkel, D. E.; Izumi, N.; Kilkenny, J. D.; Khan, S. F.; Knauer, J. P.; Kritcher, A. L.; Merrill, F. E.; Moody, J. D.; Nagel, S. R.; Park, H.-S.; Salmonson, J. D.; Sayre, D. B.; Callahan, D. A.; Hsing, W. W.; Hurricane, O. A.; Patel, P. K.; Edwards, M. J.

    2016-07-01

    A technique for measuring residual motion during the stagnation phase of an indirectly driven inertial confinement experiment has been implemented. This method infers a velocity from spatially and temporally resolved images of the X-ray emission from two orthogonal lines of sight. This work investigates the accuracy of recovering spatially resolved velocities from the X-ray emission data. A detailed analytical and numerical modeling of the X-ray emission measurement shows that the accuracy of this method increases as the displacement that results from a residual velocity increase. For the typical experimental configuration, signal-to-noise ratios, and duration of X-ray emission, it is estimated that the fractional error in the inferred velocity rises above 50% as the velocity of emission falls below 24 μm/ns. By inputting measured parameters into this model, error estimates of the residual velocity as inferred from the X-ray emission measurements are now able to be generated for experimental data. Details of this analysis are presented for an implosion experiment conducted with an unintentional radiation flux asymmetry. The analysis shows a bright localized region of emission that moves through the larger emitting volume at a relatively higher velocity towards the location of the imposed flux deficit. This technique allows for the possibility of spatially resolving velocity flows within the so-called central hot spot of an implosion. This information would help to refine our interpretation of the thermal temperature inferred from the neutron time of flight detectors and the effect of localized hydrodynamic instabilities during the stagnation phase. Across several experiments, along a single line of sight, the average difference in magnitude and direction of the measured residual velocity as inferred from the X-ray and neutron time of flight detectors was found to be ˜13 μm/ns and ˜14°, respectively.

  1. 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

    A. M. Salem; Rania Fathy

    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.

  2. Quality Standard Research of Pills for Dispersing Stagnated Liver Qi for Promoting Bile Flow%疏肝利胆丸质量检测方法研究

    杨瑞芳; 王静

    2015-01-01

    目的:建立疏肝利胆丸的质量控制标准。方法对处方中的党参、炒扁豆、姜厚朴、炒莱菔子、郁金、茯苓进行显微鉴别,同时对君药当归中的阿魏酸进行薄层鉴别。结果显微鉴别方法简单,易操作,薄层鉴别专属性强,方法可行。结论显微及薄层鉴别中所用方法简便,专属性强,重现性好,为疏肝利胆丸质量评价提供了依据。%Objective To establish the quality standard of pills for dispersing stagnated liver qi for promoting bile flow .Methods Conduct microscopic identification of Radix Codonopsis , fried lentils, Medicinal Magnolia Bark slices stir -baked with ginger juice, fried semen Raphani, curcuma root, poria in the prescription and at the meanwhile conduct TLC identification of ferulic acid in Angelica sinensis monarch drug .Results Microscopic identification is simple , easy to operate;TLC identification is high-ly specific and feasible .Conclusion The methods used in microscopic and TLC identification are easy , highly specific and reproducible , which provide the basis for quality evaluation of pills for dispersing stag-nated liver qi for promoting bile flow .

  3. Achieving diagnosis by consensus

    Kane, Bridget

    2009-08-01

    This paper provides an analysis of the collaborative work conducted at a multidisciplinary medical team meeting, where a patient’s definitive diagnosis is agreed, by consensus. The features that distinguish this process of diagnostic work by consensus are examined in depth. The current use of technology to support this collaborative activity is described, and experienced deficiencies are identified. Emphasis is placed on the visual and perceptual difficulty for individual specialities in making interpretations, and on how, through collaboration in discussion, definitive diagnosis is actually achieved. The challenge for providing adequate support for the multidisciplinary team at their meeting is outlined, given the multifaceted nature of the setting, i.e. patient management, educational, organizational and social functions, that need to be satisfied.

  4. Achieving English Spoken Fluency

    王鲜杰

    2000-01-01

    Language is first and foremost oral,spoken language,speaking skill is the most important one of the four skills(L,S,R,W)and also it is the most difficult one of the four skills. To have an all-round command of a language one must be able to speak and to understand the spoken language, it is not enough for a language learner only to have a good reading and writing skills. As Englisn language teachers, we need to focus on improving learners' English speaking skill to meet the need of our society and our country and provide learner some useful techniques to achieving their English spoken fluency. This paper focuses on the spoken how to improving learners speaking skill.

  5. What Works Clearinghouse Quick Review: "Closing the Social-Class Achievement Gap: A Difference-Education Intervention Improves First-Generation Students' Academic Performance and All Students' College Transition"

    What Works Clearinghouse, 2014

    2014-01-01

    This study measured the impact of a difference-education intervention on the academic achievement of first generation college students. The difference-education intervention teaches students how their social class backgrounds can affect what they experience in college. Participants attended a moderated panel discussion featuring demographically…

  6. Achievement Goals and Achievement Emotions: A Meta-Analysis

    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…

  7. Achieving the Goals of Sports Organizations

    Horal, Filip

    2009-01-01

    The theoretical part focuses on setting and achieving of goals in organizations in general and identifies specific performance objectives in sports organizations. In the practical part examines the process of setting targets and performance in sport organizations to Jindřichohradecko.

  8. Decomposing Achievement Gaps among OECD Countries

    Zhang, Liang; Lee, Kristen A.

    2011-01-01

    In this study, we use decomposition methods on PISA 2006 data to compare student academic performance across OECD countries. We first establish an empirical model to explain the variation in academic performance across individuals, and then use the Oaxaca-Blinder decomposition method to decompose the achievement gap between each of the OECD…

  9. Achievable efficiencies for probabilistically cloning the states

    Gao, Ting; Yan, Fengli; Wang, Zhixi

    2003-01-01

    We present an example of quantum computational tasks whose performance is enhanced if we distribute quantum information using quantum cloning. Furthermore we give achievable efficiencies for probabilistic cloning the quantum states used in implemented tasks for which cloning provides some enhancement in performance.

  10. A Structural Model of Medical Student Achievement.

    Sheehan, T. Joseph; Sanford, Keat

    1990-01-01

    The theoretical model of medical student performance begins with 38 measures, reduced to 18 without loss of information. These measures are shown to reflect five underlying theoretical interrelated variables: medical knowledge; clinical performance; science aptitude; college achievement; and attitudes and values. Results should be useful in…

  11. Entrepreneur achievement. Liaoning province.

    Zhao, R

    1994-03-01

    This paper reports the successful entrepreneurial endeavors of members of a 20-person women's group in Liaoning Province, China. Jing Yuhong, a member of the Family Planning Association at Shileizi Village, Dalian City, provided the basis for their achievements by first building an entertainment/study room in her home to encourage married women to learn family planning. Once stocked with books, magazines, pamphlets, and other materials on family planning and agricultural technology, dozens of married women in the neighborhood flocked voluntarily to the room. Yuhong also set out to give these women a way to earn their own income as a means of helping then gain greater equality with their husbands and exert greater control over their personal reproductive and social lives. She gave a section of her farming land to the women's group, loaned approximately US$5200 to group members to help them generate income from small business initiatives, built a livestock shed in her garden for the group to raise marmots, and erected an awning behind her house under which mushrooms could be grown. The investment yielded $12,000 in the first year, allowing each woman to keep more than $520 in dividends. Members then soon began going to fairs in the capital and other places to learn about the outside world, and have successfully ventured out on their own to generate individual incomes. Ten out of twenty women engaged in these income-generating activities asked for and got the one-child certificate. PMID:12287775

  12. HEPEX - achievements and challenges!

    Pappenberger, Florian; Ramos, Maria-Helena; Thielen, Jutta; Wood, Andy; Wang, Qj; Duan, Qingyun; Collischonn, Walter; Verkade, Jan; Voisin, Nathalie; Wetterhall, Fredrik; Vuillaume, Jean-Francois Emmanuel; Lucatero Villasenor, Diana; Cloke, Hannah L.; Schaake, John; van Andel, Schalk-Jan

    2014-05-01

    HEPEX is an international initiative bringing together hydrologists, meteorologists, researchers and end-users to develop advanced probabilistic hydrological forecast techniques for improved flood, drought and water management. HEPEX was launched in 2004 as an independent, cooperative international scientific activity. During the first meeting, the overarching goal was defined as: "to develop and test procedures to produce reliable hydrological ensemble forecasts, and to demonstrate their utility in decision making related to the water, environmental and emergency management sectors." The applications of hydrological ensemble predictions span across large spatio-temporal scales, ranging from short-term and localized predictions to global climate change and regional modeling. Within the HEPEX community, information is shared through its blog (www.hepex.org), meetings, testbeds and intercompaison experiments, as well as project reportings. Key questions of HEPEX are: * What adaptations are required for meteorological ensemble systems to be coupled with hydrological ensemble systems? * How should the existing hydrological ensemble prediction systems be modified to account for all sources of uncertainty within a forecast? * What is the best way for the user community to take advantage of ensemble forecasts and to make better decisions based on them? This year HEPEX celebrates its 10th year anniversary and this poster will present a review of the main operational and research achievements and challenges prepared by Hepex contributors on data assimilation, post-processing of hydrologic predictions, forecast verification, communication and use of probabilistic forecasts in decision-making. Additionally, we will present the most recent activities implemented by Hepex and illustrate how everyone can join the community and participate to the development of new approaches in hydrologic ensemble prediction.

  13. Progress, Wealth, and Mathematics Achievement

    Valero, Paola

    2013-01-01

    , professional associations argue that the low numbers of people in STEM fields can severely damage the competitiveness of developed nations in international, globalized markets. The narrative that connects progress, economic superiority, and development to citizen’s mathematical competence is made intelligible...... as a result, among others, of the growing series of comparative information on educational achievement and development. Such reports can be seen as performances of the comparative logic of Modernity that operates differential positioning, not only among individuals but also among nations, with respect to what......, H. (1899). Préface. L' Enseignement Mathématique, 1(1), 1-5. Popkewitz, T. S. (2008). Cosmopolitanism and the age of school reform: Science, education, and making society by making the child. New York: Routledge....

  14. Cognitive Skills, Student Achievement Tests, and Schools

    Finn, Amy S.; Kraft, Matthew A.; West, Martin R.; Leonard, Julia Anne; Bish, Crystal E.; Martin, Rebecca E.; Sheridan, Margaret A.; Gabrieli, Christopher F. O.; Gabrieli, John D. E.

    2013-01-01

    Cognitive skills predict academic performance, so schools that improve academic performance might also improve cognitive skills. To investigate the impact schools have on both academic performance and cognitive skills, we related standardized achievement-test scores to measures of cognitive skills in a large sample (N = 1,367) of eighth-grade students attending traditional, exam, and charter public schools. Test scores and gains in test scores over time correlated with measures of cognitive s...

  15. Cognitive Skills, Student Achievement Tests, and Schools

    Finn, Amy S.; Kraft, Matthew A.; West, Martin R.; Leonard, Julia A.; Bish, Crystal E.; Martin, Rebecca E.; Sheridan, Margaret A.; Gabrieli, Christopher F. O.; Gabrieli, John D. E.

    2014-01-01

    Cognitive skills predict academic performance, so schools that improve academic performance might also improve cognitive skills. To investigate the impact schools have on both academic performance and cognitive skills, we related standardized achievement test scores to measures of cognitive skills in a large sample (N=1,367) of 8th-grade students attending traditional, exam, and charter public schools. Test scores and gains in test scores over time correlated with measures of cognitive skills...

  16. Bilingualism and academic achievement.

    Han, Wen-Jui

    2012-01-01

    Using the Early Childhood Longitudinal Study, Kindergarten Cohort, this study examines the role that bilingualism plays in children's academic developmental trajectories during their early school years, with particular attention on the school environment (N = 16,380). Growth-curve results showed that despite starting with lower math scores in kindergarten, Mixed Bilingual children fully closed the math gap with their White English Monolingual peers by fifth grade. However, because non-English-Dominant Bilinguals and non-English Monolinguals started kindergarten with significantly lower reading and math scores compared to their English Monolingual peers, by fifth grade the former groups still had significantly lower scores. School-level factors explained about one third of the reductions in the differences in children's academic performance. PMID:22098584

  17. Cognitive skills, student achievement tests, and schools.

    Finn, Amy S; Kraft, Matthew A; West, Martin R; Leonard, Julia A; Bish, Crystal E; Martin, Rebecca E; Sheridan, Margaret A; Gabrieli, Christopher F O; Gabrieli, John D E

    2014-03-01

    Cognitive skills predict academic performance, so schools that improve academic performance might also improve cognitive skills. To investigate the impact schools have on both academic performance and cognitive skills, we related standardized achievement-test scores to measures of cognitive skills in a large sample (N = 1,367) of eighth-grade students attending traditional, exam, and charter public schools. Test scores and gains in test scores over time correlated with measures of cognitive skills. Despite wide variation in test scores across schools, differences in cognitive skills across schools were negligible after we controlled for fourth-grade test scores. Random offers of enrollment to oversubscribed charter schools resulted in positive impacts of such school attendance on math achievement but had no impact on cognitive skills. These findings suggest that schools that improve standardized achievement-test scores do so primarily through channels other than improving cognitive skills. PMID:24434238

  18. A systematic review of the effect of dietary exposure that could be achieved through normal dietary intake on learning and performance of school-aged children of relevance to UK schools

    Ells, Louisa J.; Hillier, Frances C; Shucksmith, Janet; Crawley, Helen; Harbige, Laurence; Shield, Julian; Wiggins, Andy; Summerbell, Carolyn D

    2008-01-01

    The aim of the present review was to perform a systematic in-depth review of the best evidence from controlled trial studies that have investigated the effects of nutrition, diet and dietary change on learning, education and performance in school-aged children (4-18 years) from the UK and other developed countries. The twenty-nine studies identified for the review examined the effects of breakfast consumption, sugar intake, fish oil and vitamin supplementation and 'good diets'. In summary, th...

  19. The Relationship between Academic Achievement and motivation in adolescents

    Dr. Shevatekar Sharada Vasant

    2012-01-01

    The study aimed to investigate the relationship between achievement motivation and academic achievement in adolescents. The adolescents (442-Boys and 358girls) were assessed using the achievement motivation Scale. Academic scores were taken from the school records. Achievement motivation appeared to influence of academic performance. Urban and rural subjects are significant differences about their educational achievement. The area being urban or rural as well as granted or non-granted, it doe...

  20. 1984—1988年中国农业增长滞缓探微%China' s Agricultural Stagnation in 1984-1988

    向为

    2015-01-01

    1978年开始试行的家庭联产承包责任制极大推动了中国农村经济的复苏和增长,但其在全国普及后,中国农业却陷入增长滞缓泥沼. 基于对河南省商城县一位老农民的采访,通过个案分析发现当时乡、村两级地方组织以提留统筹费名义向农民收取的不合理税款削弱了农民的劳作积极性,使得大量农村人口外流,从而导致1984—1988年间中国农业增长陷入滞缓境地. 此外,分析发现1987年农业增长的正向波动缘于科学技术运用的滞后效应. 1978—1988年间全国农业,特别是河南省农业的宏观数据又再次验证了提留统筹费对农业增长的消极影响和科学技术在运用过程中存在的滞后效应,由此建议将农业赋税制度作为农村经济改革的重要抓手,同时着力完善科学技术在农村的引入推广方式.%Agricultural growth in cropping sector was trapped into stagnation after Household Responsibility System had been completely popularized in rural areas in China .Based on a case study from Henan province , it is discovered that "Tiliu" and "Tongchou" taxes allocated by the local government discouraged the agricultural production when farmers with heavy tax burden flowed to cities for jobs .Hence, the agricultural stagnation from 1984—1988 is enun-ciated.The Hysteresis hypothesis that it takes some time for farmers to adopt new technology is also proposed to ex -plain the sudden impulse of agricultural growth in 1987.The state and provincial macro agricultural data are used to validate the analysis .The conclusions suggest the agricultural fiscal system be a core object of economic reform in ru -ral areas in China .In addition , the way of introducing new technology in such areas should be improved .

  1. Attitude Towards Physics and Additional Mathematics Achievement Towards Physics Achievement

    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…

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

    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.

  3. Identifying learning techniques among high achievers

    Shanmukananda P

    2013-04-01

    Full Text Available Background: In every college, it is noticed that in spite of being exposed to the same teaching modalities and adopting seemingly similar strategies, some students perform much better than their peers. This can be evaluated in the form of better academic performance in the internal assessments they undertake. This project is an endeavor to identify the learning techniques among high achievers which they employ to outperform others. We can also suggest the same to the medium and low achievers so that they can improve their academic performance. This study was conducted to identify different learning techniques adopted by high achievers and suggesting the same to medium and low achievers. Methods: After obtaining clearance from the institutional ethics committee, the high achievers were identified by selecting the upper third of the students in the ascending order of marks obtained in the consecutive three internal assessments in three consecutive batches. The identity of the students was not revealed. They were then administered an open ended questionnaire which addressed relevant issues. The most common and feasible techniques will be suggested to the medium and low achievers. Results: The respondents’ (n=101 replies were analyzed by calculating the percentages of responses, and assessing based on that, which were the most frequently adapted techniques by these high achievers Conclusions: High-achievers have a diligent study pattern; they not only study regularly, but also involve in group discussions and approach their teachers when in doubt. Additionally, they refer to other sources of information like the internet, demonstrating a proactive attitude towards studies. [Int J Basic Clin Pharmacol 2013; 2(2.000: 203-207

  4. Wire number dependence of the implosion dynamics, stagnation, and radiation output of tungsten wire arrays at Z driver

    We report results of the experimental campaign, which studied the initiation, implosion dynamics, and radiation yield of tungsten wire arrays as a function of the wire number. The wire array dimensions and mass were those of interest for the Z-pinch driven Inertial Confinement Fusion (ICF) program. An optimization study of the x-ray emitted peak power, rise time, and full width at half maximum was effectuated by varying the wire number while keeping the total array mass constant and equal to ∼5.8 mg. The driver utilized was the ∼20-MA Z accelerator before refurbishment in its usual short pulse mode of 100 ns. We studied single arrays of 20-mm diameter and 1-cm height. The smaller wire number studied was 30 and the largest 600. It appears that 600 is the highest achievable wire number with present day's technology. Radial and axial diagnostics were utilized including crystal monochromatic x-ray backlighter. An optimum wire number of ∼375 was observed which was very close to the routinely utilized 300 for the ICF program in Sandia.

  5. Wire number dependence of the implosion dynamics, stagnation, and radiation output of tungsten wire arrays at Z driver

    Mazarakis, Michael G.; Stygar, William A.; Sinars, Daniel B.; Cuneo, Michael E.; Nash, Thomas J.; Chandler, Gordon A.; Keith Matzen, M.; Porter, John L.; Struve, Kenneth W.; McDaniel, Dillon H. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185 (United States); Deeney, Christopher E. [National Nuclear Security Administration, Washington, D.C. 20585 (United States); Douglas, Melissa R. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Chittenden, Jerry [Imperial College, London, SW and 2BW (United Kingdom)

    2011-11-15

    We report results of the experimental campaign, which studied the initiation, implosion dynamics, and radiation yield of tungsten wire arrays as a function of the wire number. The wire array dimensions and mass were those of interest for the Z-pinch driven Inertial Confinement Fusion (ICF) program. An optimization study of the x-ray emitted peak power, rise time, and full width at half maximum was effectuated by varying the wire number while keeping the total array mass constant and equal to {approx}5.8 mg. The driver utilized was the {approx}20-MA Z accelerator before refurbishment in its usual short pulse mode of 100 ns. We studied single arrays of 20-mm diameter and 1-cm height. The smaller wire number studied was 30 and the largest 600. It appears that 600 is the highest achievable wire number with present day's technology. Radial and axial diagnostics were utilized including crystal monochromatic x-ray backlighter. An optimum wire number of {approx}375 was observed which was very close to the routinely utilized 300 for the ICF program in Sandia.

  6. A systematic review of the effect of dietary exposure that could be achieved through normal dietary intake on learning and performance of school-aged children of relevance to UK schools.

    Ells, L.J.; Hillier, F.C.; Shucksmith, J.; Crawley, H.; Harbige, L.; Shield, J; Wiggins, A.; Summerbell, C. D.

    2008-01-01

    The aim of the present review was to perform a systematic in-depth review of the best evidence from controlled trial studies that have investigated the effects of nutrition, diet and dietary change on learning, education and performance in school-aged children (4–18 years) from the UK and other developed countries. The twenty-nine studies identified for the review examined the effects of breakfast consumption, sugar intake, fish oil and vitamin supplementation and ‘good diets’. In summary, th...

  7. Cherokee Culture and School Achievement.

    Brown, Anthony D.

    1980-01-01

    Compares the effect of cooperative and competitive behaviors of Cherokee and Anglo American elementary school students on academic achievement. Suggests changes in teaching techniques and lesson organization that might raise academic achievement while taking into consideration tribal traditions that limit scholastic achievement in an…

  8. Mixed Convection Boundary-layer Flow of a Nanofluid Near Stagnation-point on a Vertical Plate with Effects of Buoyancy Assisting and Opposing Flows

    Hossein Tamim

    2013-07-01

    Full Text Available In this study, the steady laminar mixed convection boundary layer flow of a nanofluid near the stagnation-point on a vertical plate with prescribed surface temperature is investigated. Here, both assisting and opposing flows are considered and studied. Using appropriate transformations, the system of partial differential equations is transformed into an ordinary differential system of two equations, which is solved numerically by shooting method, coupled with Runge-Kutta scheme. Three different types of nanoparticles, namely copper Cu, alumina Al2O3 and titania TiO2 with water as the base fluid are considered. Numerical results are obtained for the skin-friction coefficient and Nusselt number as well as for the velocity and temperature profiles for some values of the governing parameters, namely, the nanoparticle volume fraction parameter &Phiand mixed convection parameter &lambda It is found that the highest rate of heat transfer occurs in the mixed convection with assisting flow while the lowest one occurs in the mixed convection with opposing flow. Moreover, the skin friction coefficient and the heat transfer rate at the surface are highest for copper–water nanofluid compared to the alumina–water and titania–water nanofluids.

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

    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.

  10. 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.

    Adeniyan, A.,

    2013-09-01

    Full Text Available 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 suction or injection. The governing coupled partial differential equations have been reduced to a set of coupled nonlinear ordinary differential equations by means of the similarity transformation , which has been solved using the classical fourth order Runge-Kutta method alongside with a shooting technique. The computational results have been presented by means of the table and discussed graphically. It has been observed that pertinent and invaluable engineering parameters such as the Skin-friction coefficient, the plate temperature distribution, the velocity , temperature and concentration profiles are appreciably influenced by flow parameters such as the magnetic field, convective heat parameters , Prandtl number, Sherwood number, Nusselt number, etc .

  11. Factors Influencing Seminar Learning and Academic Achievement.

    Spruijt, Annemarie; Leppink, Jimmie; Wolfhagen, Ineke; Bok, Harold; Mainhard, Tim; Scherpbier, Albert; van Beukelen, Peter; Jaarsma, Debbie

    2015-01-01

    Many veterinary curricula use seminars, interactive educational group formats in which some 25 students discuss questions and issues relating to course themes. To get indications on how to optimize the seminar learning process for students, we aimed to investigate relationships between factors that seem to be important for the seminar learning process, and to determine how these seminar factors account for differences in students' achievement scores. A 57-item seminar evaluation (USEME) questionnaire was administered to students right after they attended a seminar. In total, 80 seminars distributed over years 1, 2, and 3 of an undergraduate veterinary medicine curriculum were sampled and 988 questionnaires were handed in. Principal factor analysis (PFA) was conducted on 410 questionnaires to examine which items could be grouped together as indicators of the same factor, and to determine correlations between the derived factors. Multilevel regression analysis was performed to explore the effects of these seminar factors and students' prior achievement scores on students' achievement scores. Within the questionnaire, four factors were identified that influence the seminar learning process: teacher performance, seminar content, student preparation, and opportunities for interaction within seminars. Strong correlations were found between teacher performance, seminar content, and group interaction. Prior achievement scores and, to a much lesser extent, the seminar factor group interaction appeared to account for differences in students' achievement scores. The factors resulting from the present study and their relation to the method of assessment should be examined further, for example, in an experimental setup. PMID:26075625

  12. Students’ Achievement Goals, Learning-Related Emotions and Academic Achievement

    Lüftenegger, Marko; Klug, Julia; Harrer, Katharina; Langer, Marie; Spiel, Christiane; Schober, Barbara

    2016-01-01

    In the present research, the recently proposed 3 × 2 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 3 × 2 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 3 × 2 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. PMID:27199836

  13. Students' Achievement Goals, Learning-Related Emotions and Academic Achievement.

    Lüftenegger, Marko; Klug, Julia; Harrer, Katharina; Langer, Marie; Spiel, Christiane; Schober, Barbara

    2016-01-01

    In the present research, the recently proposed 3 × 2 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 3 × 2 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 3 × 2 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. PMID:27199836

  14. Students' Achievement Goals, Learning-Related Emotions and Academic Achievement

    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.

  15. Personality and academic achievement in nniversity students

    Isabel Niño de Guzmán; Arturo Calderón; Mónica Cassaretto

    2003-01-01

    The correlations among personality, academic performance and other variables in 170 university students were studied, using two instruments validated into the population: the NEOPJ-R, and the EPPS. Other variables as age, study level, self perception of academic achievement and self perception of motivation, and sources of support were included. Jt was confirmed the reliability and validity of both tests and the correlations between them. The results showed associations among academic perform...

  16. Numerical investigation of oxygen permeation and methane oxy-combustion in a stagnation flow ion transport membrane reactor

    In this work, a two-step oxy-combustion reaction kinetics model for methane-oxygen combustion is used to predict the oxy-combustion characteristics in the permeate side of the membrane. More accurate permeation rate characteristics inside this simple symmetric design ITM reactor is also expected using this model. New oxygen permeation model is introduced in this work for an LSCF-1991 ion transport membrane. The simulation of the oxygen permeation process across the membrane has been performed through series of visual C++ user defined function compiled and incorporated to FLUENT. The analysis of the permeation process has been conducted for separation only process (no reactions) using an inert gas (argon) as a sweep gas and a comparison has been done with cases of using CH4 plus CO2 as sweep gases. The effect of reactivity using the same sweep gases (CH4 plus CO2) is investigated by comparing the same cases with and without reactions in the permeate side. It was found that there are important parameters affecting the operation of ITM reactors like the inlet gases temperature, percentage of CH4 in the sweep gases mixture and the reactor geometry. Also, there are less important parameters like, feed and sweep volume flow rates, oxygen partial pressure in the feed side. - Highlights: • More accurate two-step methane oxy-combustion reaction kinetics model is introduced. • A new coefficients oxygen permeation equation model is introduced. • A detailed 2D study is presented to understand the performance of ITM reactors. • Using of CH4+CO2 as sweep gases is better than using argon for separation only process. • Chemical reactions have a great effect on enhancing the oxygen permeation flux

  17. Attitude towards Physics and Additional Mathematics Achievement towards Physics Achievement

    Arsaythamby Veloo; Rahimah Nor; Rozalina Khalid

    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 Physics, career related to Physics, importance of Physics, difficulty of understanding Physics, Physics teachers and Physics equipment usage. The re...

  18. Is achievement in Australian chemistry gender based?

    Beard, John; Fogliani, Charles; Owens, Chris; Wilson, Audrey

    1993-12-01

    This paper compares the performances of female and male secondary students in the 1991 and 1992 Australian National Chemistry Quizzes. Male students consistently achieved a higher mean score in all Year groups (7 to 12), even though the numbers of female and male entrants were approximately equal. Implications for class tests and assessment tasks are addressed.

  19. Science Achievement of Secondary Agricultural Education Students

    Clark, Sara Vicky

    2012-01-01

    The purposes of this quantitative descriptive and correlational study were to describe the science achievements of secondary agricultural education students and determine if the number of agricultural education courses passed, FFA involvement, and SAE participation would statistically significantly improve students' performance on science…

  20. Student Perceptions of High-Achieving Classmates

    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…

  1. Recent Achievement of Gas Electron Multiplier

    XIA Yi-ben; WANG Lin-jun; ZHANG Ming-long; YANG Ying; ZHANG Wei-li; RUAN Jian-feng

    2004-01-01

    Gas electron multiplier (GEM) as a novel gas detector, due to it's simple structure, high performance, well compatibility etc. ,is widely used in high-energy physics, nuclear physics and other fields. In this review, the principle, recent achievements,developments and applications of GEM are mainly described.

  2. APPLICATION OF ANT COLONY OPTIMISATION ALGORITHM WITH STAGNATION DETECTION IN 2D HP LATTICE MODEL%带有停滞检测的蚁群算法在2D HP 格点模型中的应用

    刘羽; 熊壬浩

    2016-01-01

    为了提高蛋白质折叠结构预测的求解效率,针对2D HP 格点模型,研究蚁群 ACO(Ant Colony Optimization)算法在该问题上的应用。采用四元组表示绝对的折叠方向,并建立构象和解的一一对应关系。通过实验对算法各阶段的常用策略、方法进行比较分析。为了防止搜索陷入停滞,引入位置信息素停滞比和序列信息素停滞比两个参数,使用一种新的停滞检测机制。实验结果表明,改进的算法在保证预测质量的前提下,显著地提升了收敛速度。%Aiming at 2D HP lattice model we studied the application of ant colony optimisation algorithm on protein folding structure prediction in order to improve the efficiency of its solution.We used the quadruple to express absolute folding direction,and established the one-to-one correspondence between conformation and solution.Through experiment we made the comparative analyses on common strategies and methods in each stage of the algorithm.To prevent the search from going to stagnation,we introduced two parameters,the position pheromone stagnation ratio and the sequence pheromone stagnation ratio,and applied a new stagnation detection mechanism as well. Experimental results showed that the improved algorithm remarkably accelerated the convergence speed on the premise of ensuring prediction quality.

  3. Academic Achievement Among Juvenile Detainees.

    Grigorenko, Elena L; Macomber, Donna; Hart, Lesley; Naples, Adam; Chapman, John; Geib, Catherine F; Chart, Hilary; Tan, Mei; Wolhendler, Baruch; Wagner, Richard

    2015-01-01

    The literature has long pointed to heightened frequencies of learning disabilities (LD) within the population of law offenders; however, a systematic appraisal of these observations, careful estimation of these frequencies, and investigation of their correlates and causes have been lacking. Here we present data collected from all youth (1,337 unique admissions, mean age 14.81, 20.3% females) placed in detention in Connecticut (January 1, 2010-July 1, 2011). All youth completed a computerized educational screener designed to test a range of performance in reading (word and text levels) and mathematics. A subsample (n = 410) received the Wide Range Achievement Test, in addition to the educational screener. Quantitative (scale-based) and qualitative (grade-equivalence-based) indicators were then analyzed for both assessments. Results established the range of LD in this sample from 13% to 40%, averaging 24.9%. This work provides a systematic exploration of the type and severity of word and text reading and mathematics skill deficiencies among juvenile detainees and builds the foundation for subsequent efforts that may link these deficiencies to both more formal, structured, and variable definitions and classifications of LD, and to other types of disabilities (e.g., intellectual disability) and developmental disorders (e.g., ADHD) that need to be conducted in future research. PMID:24064502

  4. 年级之间学业情绪与学业成绩的研究成果及展望%Research Achievements and Outlooks on the Correlation between Academic Emotions and Academic Performance

    陈维维; 黄丽婷; 梁源; 蒋莎莎

    2013-01-01

      学业情绪是影响学生学业成绩的非智力的重要因素之一,研究两者之间的关系对教学有重大的意义。通过对不同年级学业情绪与学业成绩的研究成果进行分析和对比,探究不同阶段间两者相互关系存在的普遍性以及特殊性,为更好地改善教学方式,真正做到因材施教提供依据,并由此展望学业情绪未来的发展趋向。%  Academic emotion is one of the important non-intelligent factors influencing students’ academic performance. The correlation between academic emotion and students’ academic performance is analyzed between different grades, so as to investigate their universality and particularity, and to provide reference for teaching in accordance with students’ aptitude, as well as for the prediction on the outlook of students’ academic emotional tendency.

  5. To Achieve or Not to Achieve: The Question of Women.

    Gilmore, Beatrice

    Questionnaire and projective data from 323 women aged 18 to 50 were analyzed in order to study the relationships of need achievement and motive to avoid success to age, sex role ideology, and stage in the family cycle. Family background and educational variables were also considered. Level of need achievement was found to be significantly related…

  6. Attribution theory in science achievement

    Craig, Martin

    Recent research reveals consistent lags in American students' science achievement scores. Not only are the scores lower in the United States compared to other developed nations, but even within the United States, too many students are well below science proficiency scores for their grade levels. The current research addresses this problem by examining potential malleable factors that may predict science achievement in twelfth graders using 2009 data from the National Assessment of Educational Progress (NAEP). Principle component factor analysis was conducted to determine the specific items that contribute to each overall factor. A series of multiple regressions were then analyzed and formed the predictive value of each of these factors for science achievement. All significant factors were ultimately examined together (also using multiple regression) to determine the most powerful predictors of science achievement, identifying factors that predict science achievement, the results of which suggested interventions to strengthen students' science achievement scores and encourage persistence in the sciences at the college level and beyond. Although there is a variety of research highlighting how students in the US are falling behind other developing nations in science and math achievement, as yet, little research has addressed ways of intervening to address this gap. The current research is a starting point, seeking to identify malleable factors that contribute to science achievement. More specifically, this research examined the types of attributions that predict science achievement in twelfth grade students.

  7. Predicting genetics achievement in nonmajors college biology

    Mitchell, Angela; Lawson, Anton E.

    Students enrolled in a non-majors college biology course were pretested to determine their level of intellectual development, degree of field independence, mental capacity, amount of prior genetics knowledge, and amount of fluid intelligence. They were then taught a unit on Mendelian genetics. The only student variables found to not account for a significant amount of variance on a test of reading comprehension and/or a test of genetics achievement was amount of prior genetics knowledge. Developmental level was found to be the most consistent predictor of performance, suggesting that a lack of general hypothetico-deductive reasoning ability is a major factor limiting achievement among these students.

  8. Is Preschool Executive Function Causally Related to Academic Achievement?

    Willoughby, Michael T.; Kupersmidt, Janis; Voegler-Lee, Mary

    2011-01-01

    The primary objective of this study was to re-evaluate the well-established result that preschoolers’ performance on executive function tasks are positively associated with their performance on academic achievement tests. The current study replicated the previously established concurrent associations between children’s performance on EF tasks and academic achievement tests. Specifically, children’s performance on measures of inhibitory and motor control were positively associated with their p...

  9. The Process of Science Achievement.

    Papanastasiou, Constantinos; Papanastasiou, Elena C.

    2002-01-01

    Investigates the science achievement of 8th grade students in Cyprus by using a structural equation model with three exogenous constructs--family's educational background, reinforcements, and school climate, and three endogenous constructs--teaching, student attitudes, and achievement. Proposes a model for the effects of family, school, student…

  10. Predicting Achievement in Foreign Language.

    Hart, Mary Elizabeth

    A review of research is inconclusive concerning the relationship between intelligence and language proficiency. A study of 10th grade students (n=35) examined scores on a high school entrance exam and achievement in foreign language after 1 year of study. Both math and reading showed a significant correlation with foreign language achievement; the…

  11. Healthy Eating and Academic Achievement

    2014-12-09

    This podcast highlights the evidence that supports the link between healthy eating and improved academic achievement. It also identifies a few actions to support a healthy school nutrition environment to improve academic achievement.  Created: 12/9/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 12/9/2014.

  12. Perils of Standardized Achievement Testing

    Haladyna, Thomas M.

    2006-01-01

    This article argues that the validity of standardized achievement test-score interpretation and use is problematic; consequently, confidence and trust in such test scores may often be unwarranted. The problem is particularly severe in high-stakes situations. This essay provides a context for understanding standardized achievement testing, then…

  13. Peer relationships and academic achievement

    Krnjajić Stevan B.

    2002-01-01

    Full Text Available After their childhood, when children begin to establish more intensive social contacts outside family, first of all, in school setting, their behavior i.e. their social, intellectual, moral and emotional development is more strongly affected by their peers. Consequently, the quality of peer relationships considerably affects the process of adaptation and academic achievement and their motivational and emotional attitude towards school respectively. Empirical findings showed that there is bi-directional influence between peer relationships and academic achievement. In other words, the quality of peer relationships affects academic achievement, and conversely, academic achievement affects the quality of peer relationships. For example, socially accepted children exhibiting prosocial, cooperative and responsible forms of behavior in school most frequently have high academic achievement. On the other hand, children rejected by their peers often have lower academic achievement and are a risk group tending to delinquency, absenteeism and drop out of school. Those behavioral and interpersonal forms of competence are frequently more reliable predictors of academic achievement than intellectual abilities are. Considering the fact that various patterns of peer interaction differently exert influence on students' academic behavior, the paper analyzed effects of (a social competence, (b social acceptance/rejection, (c child's friendships and (d prosocial behavior on academic achievement.

  14. Physical Activity and Academic Achievement

    2014-12-09

    This podcast highlights the evidence that supports the link between physical activity and improved academic achievement. It also identifies a few actions to support a comprehensive school physical activity program to improve academic achievement.  Created: 12/9/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 12/9/2014.

  15. Achieving single channel, full duplex wireless communication

    Choi, Jung Il

    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.

  16. Academic achievement in high functioning autistic individuals.

    Minshew, N J; Goldstein, G; Taylor, H G; Siegel, D J

    1994-04-01

    Academic achievement levels in 54 high functioning (IQ > 70) autistic subjects were compared with those of 41 normal controls, who did not differ significantly in age, IQ, gender, race, or SES from the autistic subjects. The measures of academic achievement used included portions of the Detroit Tests of Learning Aptitude-2, the Woodcock Reading Mastery Test, and the Kaufman Test of Educational Achievement. Based on prior neuropsychological findings, it was hypothesized that autistic subjects would not differ from controls on subtests assessing mechanical and procedural skills, but would differ on subtests measuring comprehension and interpretive skills. As predicted, the autistic subjects performed significantly less well than controls on comprehension tasks, but not on mechanical reading, spelling, and computational tasks. This pattern is at variance with the typical academic profile of individuals with disabilities in reading or spelling, but shares some features with the nonverbal learning disabilities. PMID:8021313

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

    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…

  18. Reviewing nuclear power station achievement

    For measurement of nuclear power station achievement against original purchase the usual gross output figures are of little value since the term loosely covers many different definitions. An authentically designed output figure has been established which relates to net design output plus house load at full load. Based on these figures both cumulative and moving annual load factors are measured, the latter measuring the achievement over the last year, thus showing trends with time. Calculations have been carried out for all nuclear stations in the Western World with 150 MW(e) gross design output and above. From these are shown: moving annual load factor indicating relative station achievements for all the plants; cumulative load factors from which return of investment can be calculated; average moving annual load factors for the four types of system Magnox, PWR, HWR, and BWR; and a relative comparison of achievement by country in a few cases. (U.K.)

  19. Performance of a shell-and-tube heat exchanger with spiral baffle plates

    In a conventional shell-and-tube heat exchanger, fluid contacts with tubes flowing up and down in a shell, therefore there is a defect in the heat transfer with tubes due to the stagnation portions. Fins are attached to the tubes in order to increase heat transfer efficiency, but there exists a limit. Therefore, it is necessary to improve heat exchanger performance by changing the fluid flow in the shell. In this study, a highly efficient shell-and-tube heat exchanger with spiral baffle plates is simulated three-dimensionally using a commercial thermal-fluid analysis code, CFX4.2. In this type of heat exchanger, fluid contacts with tubes flowing rotationally in the shell. It could improve heat exchanger performance considerably because stagnation portions in the shell could be removed. It is proved that the shell-and-tube heat exchanger with spiral baffle plates is superior to the conventional heat exchanger in terms of heat transfer

  20. Hungary's banking sector: achievements and challenges

    Várhegyi, Éva

    2002-01-01

    Hungary is generally considered one of the best performing transition countries, having been successful in achieving macroeconomic stabilisation and in creating a market-driven economic system (see, for instance, Fischer and Sahay, 2000; and Weder, 2001). In terms of financial sector reforms, the country is also considered in the advanced league (Bokros, 2001). While we agree to this assessment, it is also true that the degree of monetisation and bank intermediation in the Hungarian economy i...