Sample records for achieved experimental results

  1. A computer-based measure of resultant achievement motivation.

    PubMed

    Blankenship, V

    1987-08-01

    Three experiments were conducted to develop a computer-based measure of individual differences in resultant achievement motivation (RAM) on the basis of level-of-aspiration, achievement motivation, and dynamics-of-action theories. In Experiment 1, the number of atypical shifts and greater responsiveness to incentives on 21 trials with choices among easy, intermediate, and difficult levels of an achievement-oriented game were positively correlated and were found to differentiate the 62 subjects (31 men, 31 women) on the amount of time they spent at a nonachievement task (watching a color design) 1 week later. In Experiment 2, test-retest reliability was established with the use of 67 subjects (15 men, 52 women). Point and no-point trials were offered in blocks, with point trials first for half the subjects and no-point trials first for the other half. Reliability was higher for the atypical-shift measure than for the incentive-responsiveness measure and was higher when points were offered first. In Experiment 3, computer anxiety was manipulated by creating a simulated computer breakdown in the experimental condition. Fifty-nine subjects (13 men, 46 women) were randomly assigned to the experimental condition or to one of two control conditions (an interruption condition and a no-interruption condition). Subjects with low RAM, as demonstrated by a low number of typical shifts, took longer to choose the achievement-oriented task, as predicted by the dynamics-of-action theory. The difference was evident in all conditions and most striking in the computer-breakdown condition. A change of focus from atypical to typical shifts is discussed.

  2. Experimental and Theoretical Study on Minimum Achievable Foil Thickness during Asymmetric Rolling

    PubMed Central

    Tang, Delin; Liu, Xianghua; Song, Meng; Yu, Hailiang

    2014-01-01

    Parts produced by microforming are becoming ever smaller. Similarly, the foils required in micro-machines are becoming ever thinner. The asymmetric rolling technique is capable of producing foils that are thinner than those produced by the conventional rolling technique. The difference between asymmetric rolling and conventional rolling is the ‘cross-shear’ zone. However, the influence of the cross-shear zone on the minimum achievable foil thickness during asymmetric rolling is still uncertain. In this paper, we report experiments designed to understand this critical influencing factor on the minimum achievable thickness in asymmetric rolling. Results showed that the minimum achievable thickness of rolled foils produced by asymmetric rolling with a rolling speed ratio of 1.3 can be reduced to about 30% of that possible by conventional rolling technique. Furthermore, the minimum achievable thickness during asymmetric rolling could be correlated to the cross-shear ratio, which, in turn, could be related to the rolling speed ratio. From the experimental results, a formula to calculate the minimum achievable thickness was established, considering the parameters cross-shear ratio, friction coefficient, work roll radius, etc. in asymmetric rolling. PMID:25203265

  3. Developing students’ learning achievement and experimental skills on buoyancy and the involvement of Newton’s third law through experimental sets

    NASA Astrophysics Data System (ADS)

    Chokchai, Jaewijarn; Khanti, Toedtanya; Sura, Wuttiprom

    2017-09-01

    The purposes of this research were: to construct packages of operations on buoyancy and the involvement of Newton’s third law, to enhance achievement score of students on buoyancy and the involvement of Newton’s third law, to enhance experimental skills on buoyancy and the involvement of Newton’s third law and to evaluate students’ attitude towards the packages of operations on buoyancy and the involvement of Newton’s third law using inquiry method. The samples were 42 grade 11 students in academic year 2016 at Hatyaiwittayalai School, Hatyai, Songkhla. The research method was one group pretest-posttest design. The research tools consisted of experimental set on buoyancy and the involvement of Newton’s third law, the learning achievement test on buoyancy and the involvement of Newton’s third law and the students’ attitude questionnaires. The experimental skills of most students was in a good level . The satisfaction of most students was in a good level. The research showed the learning achievement after instruction higher than that before instruction using experimental set at the significant level of 0.05 and the class average normalized gain is in the medium gain

  4. Design and Experimental Results for a Natural-Laminar-Flow Airfoil for General Aviation Applications

    NASA Technical Reports Server (NTRS)

    Somers, D. M.

    1981-01-01

    A natural-laminar-flow airfoil for general aviation applications, the NLF(1)-0416, was designed and analyzed theoretically and verified experimentally in the Langley Low-Turbulence Pressure Tunnel. The basic objective of combining the high maximum lift of the NASA low-speed airfoils with the low cruise drag of the NACA 6-series airfoils was achieved. The safety requirement that the maximum lift coefficient not be significantly affected with transition fixed near the leading edge was also met. Comparisons of the theoretical and experimental results show excellent agreement. Comparisons with other airfoils, both laminar flow and turbulent flow, confirm the achievement of the basic objective.

  5. "No Excuses" Charter Schools: A Meta-Analysis of the Experimental Evidence on Student Achievement

    ERIC Educational Resources Information Center

    Cheng, Albert; Hitt, Collin; Kisida, Brian; Mills, Jonathan N.

    2017-01-01

    Many most well-known charter schools in the United States use a "No Excuses" approach. We conduct the first meta-analysis of the achievement impacts of No Excuses charter schools, focusing on experimental, lottery-based studies. We estimate that No Excuses charter schools increase student math and literacy achievement by 0.25 and 0.17,…

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

    PubMed

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

    2009-11-01

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

  7. Experimental and Theoretical Results in Output Trajectory Redesign for Flexible Structures

    NASA Technical Reports Server (NTRS)

    Dewey, J. S.; Leang, K.; Devasia, S.

    1998-01-01

    In this paper we study the optimal redesign of output trajectories for linear invertible systems. This is particularly important for tracking control of flexible structures because the input-state trajectores, that achieve tracking of the required output may cause excessive vibrations in the structure. We pose and solve this problem, in the context of linear systems, as the minimization of a quadratic cost function. The theory is developed and applied to the output tracking of a flexible structure and experimental results are presented.

  8. Achieving optimal SERS through enhanced experimental design

    PubMed Central

    Fisk, Heidi; Westley, Chloe; Turner, Nicholas J.

    2016-01-01

    One of the current limitations surrounding surface‐enhanced Raman scattering (SERS) is the perceived lack of reproducibility. SERS is indeed challenging, and for analyte detection, it is vital that the analyte interacts with the metal surface. However, as this is analyte dependent, there is not a single set of SERS conditions that are universal. This means that experimental optimisation for optimum SERS response is vital. Most researchers optimise one factor at a time, where a single parameter is altered first before going onto optimise the next. This is a very inefficient way of searching the experimental landscape. In this review, we explore the use of more powerful multivariate approaches to SERS experimental optimisation based on design of experiments and evolutionary computational methods. We particularly focus on colloidal‐based SERS rather than thin film preparations as a result of their popularity. © 2015 The Authors. Journal of Raman Spectroscopy published by John Wiley & Sons, Ltd. PMID:27587905

  9. Achieving optimal SERS through enhanced experimental design.

    PubMed

    Fisk, Heidi; Westley, Chloe; Turner, Nicholas J; Goodacre, Royston

    2016-01-01

    One of the current limitations surrounding surface-enhanced Raman scattering (SERS) is the perceived lack of reproducibility. SERS is indeed challenging, and for analyte detection, it is vital that the analyte interacts with the metal surface. However, as this is analyte dependent, there is not a single set of SERS conditions that are universal. This means that experimental optimisation for optimum SERS response is vital. Most researchers optimise one factor at a time, where a single parameter is altered first before going onto optimise the next. This is a very inefficient way of searching the experimental landscape. In this review, we explore the use of more powerful multivariate approaches to SERS experimental optimisation based on design of experiments and evolutionary computational methods. We particularly focus on colloidal-based SERS rather than thin film preparations as a result of their popularity. © 2015 The Authors. Journal of Raman Spectroscopy published by John Wiley & Sons, Ltd.

  10. Experimental and Theoretical Results in Output-Trajectory Redesign for Flexible Structures

    NASA Technical Reports Server (NTRS)

    Dewey, J. S.; Devasia, Santosh

    1996-01-01

    In this paper we study the optimal redesign of output trajectory for linear invertible systems. This is particularly important for tracking control of flexible structures because the input-state trajectories that achieve the required output may cause excessive vibrations in the structure. A trade-off is then required between tracking and vibrations reduction. We pose and solve this problem as the minimization of a quadratic cost function. The theory is developed and applied to the output tracking of a flexible structure and experimental results are presented.

  11. Poor Results for High Achievers

    ERIC Educational Resources Information Center

    Bui, Sa; Imberman, Scott; Craig, Steven

    2012-01-01

    Three million students in the United States are classified as gifted, yet little is known about the effectiveness of traditional gifted and talented (G&T) programs. In theory, G&T programs might help high-achieving students because they group them with other high achievers and typically offer specially trained teachers and a more advanced…

  12. Magnetic Guarding: Experimental and Numerical Results

    NASA Astrophysics Data System (ADS)

    Heinrich, Jonathon; Font, Gabriel; Garrett, Michael; Rose, D.; Genoni, T.; Welch, D.; McGuire, Thomas

    2017-10-01

    The magnetic field topology of Lockheed Martin's Compact Fusion Reactor (CFR) concept requires internal magnetic field coils. Internal coils for similar devices have leveraged levitating coils or coils with magnetically guarded supports. Magnetic guarding of supports has been investigated for multipole devices (theoretically and experimentally) without conclusive results. One outstanding question regarding magnetic guarding of supports is the magnitude and behavior of secondary plasma drifts resulting from magnetic guard fields (grad-B drifts, etc). We present magnetic-implicit PIC modeling results and preliminary proof of concept experimental results on magnetic guarding of internal-supports and the subsequent reduction in total plasma losses.

  13. The 2.5 bit/detected photon demonstration program: Phase 2 and 3 experimental results

    NASA Technical Reports Server (NTRS)

    Katz, J.

    1982-01-01

    The experimental program for laboratory demonstration of and energy efficient optical communication channel operating at a rate of 2.5 bits/detected photon is described. Results of the uncoded PPM channel performance are presented. It is indicated that the throughput efficiency can be achieved not only with a Reed-Solomon code as originally predicted, but with a less complex code as well.

  14. Design and experimental results for a flapped natural-laminar-flow airfoil for general aviation applications

    NASA Technical Reports Server (NTRS)

    Somers, D. M.

    1981-01-01

    A flapped natural laminar flow airfoil for general aviation applications, the NLF(1)-0215F, has been designed and analyzed theoretically and verified experimentally in the Langley Low Turbulence Pressure Tunnel. The basic objective of combining the high maximum lift of the NASA low speed airfoils with the low cruise drag of the NACA 6 series airfoils has been achieved. The safety requirement that the maximum lift coefficient not be significantly affected with transition fixed near the leading edge has also been met. Comparisons of the theoretical and experimental results show generally good agreement.

  15. Boston Community Information System 1986 Experimental Test Results.

    DTIC Science & Technology

    1987-08-01

    self -selected participants have a strong technical orientation and high educational achievement. In addition, five visually impaired people use the...group. The experimental test of the system was performed on a self -selected population of computer literate volunteers. In order to simplify the test...for fat respose .’ - 1041 OI haven’t used it yet.’ - 1046 ’No modem yet. New version installed 11/2/86.0 - 1047 ’Not yet tried. Wil do so moon.’ - 1061

  16. Electromagnetic Vortex-Based Radar Imaging Using a Single Receiving Antenna: Theory and Experimental Results

    PubMed Central

    Yuan, Tiezhu; Wang, Hongqiang; Cheng, Yongqiang; Qin, Yuliang

    2017-01-01

    Radar imaging based on electromagnetic vortex can achieve azimuth resolution without relative motion. The present paper investigates this imaging technique with the use of a single receiving antenna through theoretical analysis and experimental results. Compared with the use of multiple receiving antennas, the echoes from a single receiver cannot be used directly for image reconstruction using Fourier method. The reason is revealed by using the point spread function. An additional phase is compensated for each mode before imaging process based on the array parameters and the elevation of the targets. A proof-of-concept imaging system based on a circular phased array is created, and imaging experiments of corner-reflector targets are performed in an anechoic chamber. The azimuthal image is reconstructed by the use of Fourier transform and spectral estimation methods. The azimuth resolution of the two methods is analyzed and compared through experimental data. The experimental results verify the principle of azimuth resolution and the proposed phase compensation method. PMID:28335487

  17. Design and Experimental Results for the S825 Airfoil; Period of Performance: 1998-1999

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Somers, D. M.

    2005-01-01

    A 17%-thick, natural-laminar-flow airfoil, the S825, for the 75% blade radial station of 20- to 40-meter, variable-speed and variable-pitch (toward feather), horizontal-axis wind turbines has been designed and analyzed theoretically and verified experimentally in the NASA Langley Low-Turbulence Pressure Tunnel. The two primary objectives of high maximum lift, relatively insensitive to roughness and low-profile drag have been achieved. The airfoil exhibits a rapid, trailing-edge stall, which does not meet the design goal of a docile stall. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results generally show good agreement.

  18. Sharing Leadership Responsibilities Results in Achievement Gains

    ERIC Educational Resources Information Center

    Armistead, Lew

    2010-01-01

    Collective, not individual, leadership in schools has a greater impact on student achievement; when principals and teachers share leadership responsibilities, student achievement is higher; and schools having high student achievement also display a vision for student achievement and teacher growth. Those are just a few of the insights into school…

  19. Experimental Results of the EU ITER Prototype Gyrotrons

    NASA Astrophysics Data System (ADS)

    Gantenbein, G.; Albajar, F.; Alberti, S.; Avramidis, K.; Bin, W.; Bonicelli, T.; Bruschi, A.; Chelis, J.; Fanale, F.; Legrand, F.; Hermann, V.; Hogge, J.-P.; Illy, S.; Ioannidis, Z. C.; Jin, J.; Jelonnek, J.; Kasparek, W.; Latsas, G. P.; Lechte, C.; Lontano, M.; Pagonakis, I. G.; Rzesnicki, T.; Schlatter, C.; Schmid, M.; Tigelis, I. G.; Thumm, M.; Tran, M. Q.; Vomvoridis, J. L.; Zein, A.; Zisis, A.

    2017-10-01

    The European 1 MW, 170 GHz CW industrial prototype gyrotron for ECRH&CD on ITER was under test at the KIT test facility during 2016. In order to optimize the gyrotron operation, the tube was thoroughly tested in the short-pulse regime, with pulse lengths below 10 ms, for a wide range of operational parameters. The operation was extended to longer pulses with a duration of up to 180 s. In this work we present in detail the achievements and the challenges that were faced during the long-pulse experimental campaign.

  20. The Bigfoot Drive; Experimental Results

    NASA Astrophysics Data System (ADS)

    Baker, Kevin; Thomas, Cliff; Khan, Shahab; Casey, Daniel; Spears, Brian; Nora, Ryan; Munro, Davis; Eder, David; Milovich, Jose; Berger, Dick; Strozzi, David; Goyon, Clement; Turnbull, David; Ma, Tammy; Izumi, Nobuhiko; Benedetti, Robin; Millot, Marius; Celliers, Peter; Yeamans, Charles; Hatarik, Robert; Landen, Nino; Hurricane, Omar; Callahan, Debbie

    2016-10-01

    The Bigfoot platform was developed on the National Ignition Facility to investigate low convergence, high adiabat, high rhoR hotspot implosions. This platform was designed to be less susceptible to wall motion, LPI and CBET and to be more robust against capsule hydrodynamic instabilities. To date experimental studies have been carried out at two hohlraum scales, a 5.75 and 5.4 mm diameter hohlraum. We will present experimental results from these tuning campaigns including the shape vs. cone fraction, surrogacy comparisons of self-emission from the capsules vs. radiography of the imploding capsule and doped vs. undoped capsules. Prepared by LLNL under Contract DE-AC52-07NA27344.

  1. Controls-structures interaction guest investigator program: Overview and phase 1 experimental results and future plans

    NASA Technical Reports Server (NTRS)

    Smith-Taylor, Rudeen; Tanner, Sharon E.

    1993-01-01

    The NASA Controls-Structures Interaction (CSI) Guest Investigator program is described in terms of its support of the development of CSI technologies. The program is based on the introduction of CSI researchers from industry and academia to available test facilities for experimental validation of technologies and methods. Phase 1 experimental results are reviewed with attention given to their use of the Mini-MAST test facility and the facility for the Advance Control Evaluation of Structures. Experiments were conducted regarding the following topics: collocated/noncollocated controllers, nonlinear math modeling, controller design, passive/active suspension systems design, and system identification and fault isolation. The results demonstrate that significantly enhanced performance from the control techniques can be achieved by integrating knowledge of the structural dynamics under consideration into the approaches.

  2. The Variation in Student Achievement and Behavior within a Portfolio Management Model: Early Results from New Orleans

    ERIC Educational Resources Information Center

    McEachin, Andrew J.; Welsh, Richard Osbourne; Brewer, Dominic James

    2016-01-01

    A growing number of states experimented with alternative governance structures in response to pressure to raise student achievement. Post-Katrina experimentation in New Orleans was widely regarded as a model example of new governance reforms and provided a unique opportunity to learn about the variation in student achievement and behavior within…

  3. Characterisation and optimisation of flexible transfer lines for liquid helium. Part I: Experimental results

    NASA Astrophysics Data System (ADS)

    Dittmar, N.; Haberstroh, Ch.; Hesse, U.; Krzyzowski, M.

    2016-04-01

    The transfer of liquid helium (LHe) into mobile dewars or transport vessels is a common and unavoidable process at LHe decant stations. During this transfer reasonable amounts of LHe evaporate due to heat leak and pressure drop. Thus generated helium gas needs to be collected and reliquefied which requires a huge amount of electrical energy. Therefore, the design of transfer lines used at LHe decant stations has been optimised to establish a LHe transfer with minor evaporation losses which increases the overall efficiency and capacity of LHe decant stations. This paper presents the experimental results achieved during the thermohydraulic optimisation of a flexible LHe transfer line. An extensive measurement campaign with a set of dedicated transfer lines equipped with pressure and temperature sensors led to unique experimental data of this specific transfer process. The experimental results cover the heat leak, the pressure drop, the transfer rate, the outlet quality, and the cool-down and warm-up behaviour of the examined transfer lines. Based on the obtained results the design of the considered flexible transfer line has been optimised, featuring reduced heat leak and pressure drop.

  4. An Overview of NSTX Research Facility and Recent Experimental Results

    NASA Astrophysics Data System (ADS)

    Ono, Masayuki

    2006-10-01

    The 2006 NSTX experimental campaign yielded significant new experimental results in many areas. Improved plasma control achieved the highest elongation of 2.9 and plasma shape factor q95Ip/aBT = 42 MA/m.T. Active feedback correction of error fields sustained the plasma rotation and increased the pulse length of high beta discharges. Active feedback stabilization of the resistive wall mode in high-beta, low-rotation plasmas was demonstrated for ˜100 resistive wall times. Operation at higher toroidal field showed favorable plasma confinement and HHFW heating efficiency trends with the field. A broader current profile, measured by the 12-channel MSE diagnostic in high beta discharges revealed an outward anomalous diffusivity of energetic ions due to the n=1 MHD modes. A tangential microwave scattering diagnostic measured localized electron gyro-scale fluctuations in L-mode, H-mode and reversed-shear plasmas. Evaporation of lithium onto plasma facing surfaces yielded lower density, higher temperature and improved confinement. A strong dependence of the divertor heat load and ELM behavior on the plasma triangularity was observed. Coaxial helicity injection produced a start-up current of 160 kA on closed flux surfaces.

  5. Recent experimental results of KSTAR RF heating and current drive

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wang, S. J., E-mail: sjwang@nfri.re.kr; Kim, J.; Jeong, J. H.

    2015-12-10

    The overview of KSTAR activities on ICRH, LHCD and ECH/CD including the last experimental results and future plan aiming for long-pulse high-beta plasma will be presented. Recently we achieved reasonable coupling of ICRF power to H-mode plasma through several efforts to increase system reliability. Power balance will be discussed on this experiment. LHCD is still struggling in the low power regime. Review of antenna spectrum for the higher coupling in H-mode plasma will be tried. ECH/CD provides 41 sec, 0.8 MW of heating power to support high-performance long-pulse discharge. Also, 170 GHz ECH system is integrated with the Plasma Control Systemmore » (PCS) for the feedback controlling of NTM. Status and plan of ECH/CD will be discussed. Finally, helicon current drive is being prepared for the next stage of KSTAR operation. The hardware preparation and the calculation results of helicon current drive in KSTAR plasma will be discussed.« less

  6. Recent experimental results of KSTAR RF heating and current drive

    NASA Astrophysics Data System (ADS)

    Wang, S. J.; Kim, J.; Jeong, J. H.; Kim, H. J.; Joung, M.; Bae, Y. S.; Kwak, J. G.

    2015-12-01

    The overview of KSTAR activities on ICRH, LHCD and ECH/CD including the last experimental results and future plan aiming for long-pulse high-beta plasma will be presented. Recently we achieved reasonable coupling of ICRF power to H-mode plasma through several efforts to increase system reliability. Power balance will be discussed on this experiment. LHCD is still struggling in the low power regime. Review of antenna spectrum for the higher coupling in H-mode plasma will be tried. ECH/CD provides 41 sec, 0.8 MW of heating power to support high-performance long-pulse discharge. Also, 170 GHz ECH system is integrated with the Plasma Control System (PCS) for the feedback controlling of NTM. Status and plan of ECH/CD will be discussed. Finally, helicon current drive is being prepared for the next stage of KSTAR operation. The hardware preparation and the calculation results of helicon current drive in KSTAR plasma will be discussed.

  7. The Effects of Learning Strategy Instruction on Achievement, Attitude, and Achievement Motivation in a Physics Course

    NASA Astrophysics Data System (ADS)

    Sezgin Selçuk, Gamze; Sahin, Mehmet; Açıkgöz, Kamile Ün

    2011-01-01

    This article reports on the influence of learning strategy instruction on student teachers' physics achievement, attitude towards physics, and achievement motivation. A pre-test/post-test quasi-experimental design with matching control group was used in the study. Two groups of student teachers ( n = 75) who were enrolled in an introductory physics course participated in the study. In the experimental group, questioning, summarizing, and graphic organizers were taught. The control group did not receive any presentation on strategy learning. Data were collected via the pre- and post-administration of the Physics Course Achievement Test, the Scale of Attitudes towards Physics, and the Achievement Motivation Scale. Univariate and multivariate analyses of variance on the data revealed no significant differences in the attitude and achievement motivation between the strategy and control groups. However, the strategy group students were observed to have a tendency of more positive attitude and motivation than the control group students. Results also showed that explicit learning strategy instruction was more effective than traditional instruction in improving physics achievement of the participating students. The implications of these results for physics education are discussed.

  8. School Counselors: Closing Achievement Gaps and Writing Results Reports

    ERIC Educational Resources Information Center

    Hartline, Julie; Cobia, Debra

    2012-01-01

    Charged with closing the achievement gap for marginalized students, school counselors need to be able to identify gaps, develop interventions, evaluate effectiveness, and share results. This study examined 100 summary results reports submitted by school counselors after having received four days of training on the ASCA National Model. Findings…

  9. Beam dynamics studies at DAΦNE: from ideas to experimental results

    NASA Astrophysics Data System (ADS)

    Zobov, M.; DAΦNE Team

    2017-12-01

    DAΦNE is the electron-positron collider operating at the energy of Φ-resonance, 1 GeV in the center of mass. The presently achieved luminosity is by about two orders of magnitude higher than that obtained at other colliders ever operated at this energy. Careful beam dynamic studies such as the vacuum chamber design with low beam coupling impedance, suppression of different kinds of beam instabilities, investigation of beam-beam interaction, optimization of the beam nonlinear motion have been the key ingredients that have helped to reach this impressive result. Many novel ideas in accelerator physics have been proposed and/or tested experimentally at DAΦNE for the first time. In this paper we discuss the advanced accelerator physics studies performed at DAΦNE.

  10. A critical review of RHIC experimental results

    NASA Astrophysics Data System (ADS)

    Trainor, Thomas A.

    2014-07-01

    The relativistic heavy-ion collider (RHIC) was constructed to achieve an asymptotic state of nuclear matter in heavy-ion collisions, a near-ideal gas of deconfined quarks and gluons denoted quark-gluon plasma or QGP. RHIC collisions are indeed very different from the hadronic processes observed at the Bevalac and AGS, but high-energy elementary-collision mechanisms are also non-hadronic. The two-component model (TCM) combines measured properties of elementary collisions with the Glauber eikonal model to provide an alternative asymptotic limit for A-A collisions. RHIC data have been interpreted to indicate formation of a strongly-coupled QGP (sQGP) or "perfect liquid". In this review, I consider the experimental evidence that seems to support such conclusions and alternative evidence that may conflict with those conclusions and suggest different interpretations.

  11. Nucleate pool boiling in subcooled liquid under microgravity: Results of TEXUS experimental investigations

    NASA Astrophysics Data System (ADS)

    Zell, M.; Straub, J.; Weinzierl, A.

    1984-12-01

    Experiments on subcooled nucleate pool boiling in microgravity were carried out to separate gravity driven effects on heat transfer within the boiling process. A ballistic trajectory by sounding rocket flight (TEXUS 5 and 10) achieved a gravity level of a/g = 0.0001 for 360 sec. For determination of geometrical effects on heat transport two different experimental configurations (platinum wire and flat plate) were employed. Boiling curves and bubble dynamics recorded by cinematography lead to gravity independent modelling of the boiling phenomena. The results ensure the applicability and high efficiency of nucleate pool boiling for heat exchangers in space laboratories.

  12. Goal Setting to Achieve Results

    ERIC Educational Resources Information Center

    Newman, Rich

    2012-01-01

    Both districts and individual schools have a very clear set of goals and skills for their students to achieve and master. In fact, except in rare cases, districts and schools develop very detailed goals they wish to pursue. In most cases, unfortunately, only the teachers and staff at a particular school or district-level office are aware of the…

  13. Assessment of practical and experimental work in physics through OCEA (Oxford Certificate of Educational Achievement)

    NASA Astrophysics Data System (ADS)

    Josephy, Richard

    1986-07-01

    For some years there has been a growing recognition of the need for changes in assessment patterns in school science. These changes include a move towards criterion-based assessment linking to objectives and an increased emphasis on the assessment of practical and experimental skills. These changes are, to a significant extent, embodied in the new GCSE assessment schemes and will thus affect all students and teachers of physics from September (1986). At least 20% of the total assessment in GCSE physics examinations must be of practical and experimental skills, and at least half of this must be carried out in the laboratory environment. One development which addresses the needs and problems outlined above is the science component of OCEA, the Oxford Certificate of Educational Achievement. Because this covers a much wider field than assessment of practical and experimental skills in physics, a brief description of the whole project is given.

  14. Quasi-experimental nonequivalent (pretest and posttest) control-group study of the effects of microcomputer-based laboratory systems on academic achievement in high school chemistry students at two South Carolina high schools

    NASA Astrophysics Data System (ADS)

    Venables, Jeffrey M.

    The literature on microcomputer-based laboratories (MBL) lacks quantitative studies that measure the effect of MBL on student achievement. The purpose of this study was to investigate the effect of MBL systems on the achievement of high school chemistry students. The first research question examined the effect of MBL systems on student achievement in high school chemistry laboratories. The second question analyzed the effect of MBL systems on the academic achievement of students of different genders, ethnicities, and socioeconomic backgrounds. This quasi-experimental quantitative research study evaluated the effects of MBL on student achievement in high school chemistry. The sample consisted of 124 college preparatory chemistry students at two high schools in a South Carolina school district. There were 42 participants in the experimental group and 82 participants in the control group. Both experimental and groups completed a pre- and post-test with MBL being the independent variable. The mean difference score for the experimental group was compared to that of the control group using an independent-measures t test and an analysis of variance. For the second research question, results were analyzed using a two-factor analysis of variance. Participant scores were broken down by gender, ethnicity, and socioeconomic status in order to identify potential differences. The results revealed no significant differences between the experimental and control groups, and no significant differences in effects of MBL on different segments of the population. Future studies should examine students using MBL for longer durations than one unit of study. As society continues to make technological advances, the effective assessment and implementation of technology resources for the classroom are becoming increasingly important.

  15. Middle Term Achievements of Project 5322: Retrieval Of Key Eco-Hydrological Parameters From Remote Sensing In The Watershed Allied Telemetry Experimental Research (Water)

    NASA Astrophysics Data System (ADS)

    Li, Xin; Menenti, Massimo

    2010-10-01

    The general objective of project 5322 in the Dragon 2 programme is to quantitatively retrieve some key eco- hydrological parameters by using remote sensed data, especially from ESA, Chinese, and the Third Party Mission (TPM). To achieve this goal, a comprehensive observation experiment, Watershed Allied Telemetry Experimental Research (WATER) was carried out. WARER is a simultaneously airborne, satellite-borne, and ground-based remote sensing experiment took place in the Heihe River Basin, a typical inland river basin in the northwest of China. This paper introduces the background and implementation of WATER. Data have been obtained so far are described in details. After a period of data analysis for two years, numerous results have also been achieved. This paper presents some early results of WATER as well.

  16. Achievement Motivation: A Rational Approach to Psychological Education

    ERIC Educational Resources Information Center

    Smith, Robert L.; Troth, William A.

    1975-01-01

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

  17. Notification: Review of Science to Achieve Results (STAR) Grant Program

    EPA Pesticide Factsheets

    Project #OA-FY12-0606, July 16, 2012. EPA’s Office of Inspector General (OIG) plans to begin preliminary research for an audit of grants awarded under EPA’s Science to Achieve Results (STAR) program.

  18. Fuel-rich, catalytic reaction experimental results

    NASA Technical Reports Server (NTRS)

    Rollbuhler, R. James

    1991-01-01

    Future aeropropulsion gas turbine combustion requirements call for operating at very high inlet temperatures, pressures, and large temperature rises. At the same time, the combustion process is to have minimum pollution effects on the environment. Aircraft gas turbine engines utilize liquid hydrocarbon fuels which are difficult to uniformly atomize and mix with combustion air. An approach for minimizing fuel related problems is to transform the liquid fuel into gaseous form prior to the completion of the combustion process. Experimentally obtained results are presented for vaporizing and partially oxidizing a liquid hydrocarbon fuel into burnable gaseous components. The presented experimental data show that 1200 to 1300 K reaction product gas, rich in hydrogen, carbon monoxide, and light-end hydrocarbons, is formed when flowing 0.3 to 0.6 fuel to air mixes through a catalyst reactor. The reaction temperatures are kept low enough that nitrogen oxides and carbon particles (soot) do not form. Results are reported for tests using different catalyst types and configurations, mass flowrates, input temperatures, and fuel to air ratios.

  19. Digital Storytelling for Enhancing Student Academic Achievement, Critical Thinking, and Learning Motivation: A Year-Long Experimental Study

    ERIC Educational Resources Information Center

    Yang, Ya-Ting C.; Wu, Wan-Chi I.

    2012-01-01

    The purpose of this study was to explore the impact of Digital storytelling (DST) on the academic achievement, critical thinking, and learning motivation of senior high school students learning English as a foreign language. The one-year study adopted a pretest and posttest quasi-experimental design involving 110 10th grade students in two English…

  20. Comparison the Results of Numerical Simulation And Experimental Results for Amirkabir Plasma Focus Facility

    NASA Astrophysics Data System (ADS)

    Goudarzi, Shervin; Amrollahi, R.; Niknam Sharak, M.

    2014-06-01

    In this paper the results of the numerical simulation for Amirkabir Mather-type Plasma Focus Facility (16 kV, 36μF and 115 nH) in several experiments with Argon as working gas at different working conditions (different discharge voltages and gas pressures) have been presented and compared with the experimental results. Two different models have been used for simulation: five-phase model of Lee and lumped parameter model of Gonzalez. It is seen that the results (optimum pressures and current signals) of the Lee model at different working conditions show better agreement than lumped parameter model with experimental values.

  1. The Direct Effects of Principal-Student Discussions upon Eighth Grade Students' Gains in Reading Achievement: An Experimental Study

    ERIC Educational Resources Information Center

    Silva, Jack P.

    2010-01-01

    School effectiveness and instructional leadership research over the past thirty years have largely concluded that principal effects on student achievement are small and indirect; it has been assumed that principal effect is important, but mediated through other school factors. To the contrary, this experimental study found that one-on-one…

  2. The Direct Effects of Principal-Student Discussions on Eighth Grade Students' Gains in Reading Achievement: An Experimental Study

    ERIC Educational Resources Information Center

    Silva, Jack P.; White, George P.; Yoshida, Roland K.

    2011-01-01

    Purpose: School effectiveness and instructional leadership research over the past 30 years has largely concluded that principal effects on student achievement are small and indirect. It has been assumed that the principal effect is important but mediated through other school factors. Findings: This experimental study found that one-on-one…

  3. Experimental results on chiral magnetic and vortical effects

    DOE PAGES

    Wang, Gang; Wen, Liwen

    2017-01-12

    Various novel transport phenomena in chiral systems result from the interplay of quantum anomalies with magnetic field and vorticity in high-energy heavy-ion collisions and could survive the expansion of the fireball and be detected in experiments. Among them are the chiral magnetic effect, the chiral vortical effect, and the chiral magnetic wave, the experimental searches for which have aroused extensive interest. As a result, the goal of this review is to describe the current status of experimental studies at Relativistic Heavy-Ion Collider at BNL and the Large Hadron Collider at CERN and to outline the future work in experiment neededmore » to eliminate the existing uncertainties in the interpretation of the data.« less

  4. Modeling and experimental result analysis for high-power VECSELs

    NASA Astrophysics Data System (ADS)

    Zakharian, Aramais R.; Hader, Joerg; Moloney, Jerome V.; Koch, Stephan W.; Lutgen, Stephan; Brick, Peter; Albrecht, Tony; Grotsch, Stefan; Luft, Johann; Spath, Werner

    2003-06-01

    We present a comparison of experimental and microscopically based model results for optically pumped vertical external cavity surface emitting semiconductor lasers. The quantum well gain model is based on a quantitative ab-initio approach that allows calculation of a complex material susceptibility dependence on the wavelength, carrier density and lattice temperature. The gain model is coupled to the macroscopic thermal transport, spatially resolved in both the radial and longitudinal directions, with temperature and carrier density dependent pump absorption. The radial distribution of the refractive index and gain due to temperature variation are computed. Thermal managment issues, highlighted by the experimental data, are discussed. Experimental results indicate a critical dependence of the input power, at which thermal roll-over occurs, on the thermal resistance of the device. This requires minimization of the substrate thickness and optimization of the design and placement of the heatsink. Dependence of the model results on the radiative and non-radiative carrier recombination lifetimes and cavity losses are evaluated.

  5. Simulation and experimental results of optical and thermal modeling of gold nanoshells.

    PubMed

    Ghazanfari, Lida; Khosroshahi, Mohammad E

    2014-09-01

    This paper proposes a generalized method for optical and thermal modeling of synthesized magneto-optical nanoshells (MNSs) for biomedical applications. Superparamagnetic magnetite nanoparticles with diameter of 9.5 ± 1.4 nm are fabricated using co-precipitation method and subsequently covered by a thin layer of gold to obtain 15.8 ± 3.5 nm MNSs. In this paper, simulations and detailed analysis are carried out for different nanoshell geometry to achieve a maximum heat power. Structural, magnetic and optical properties of MNSs are assessed using vibrating sample magnetometer (VSM), X-ray diffraction (XRD), UV-VIS spectrophotometer, dynamic light scattering (DLS), and transmission electron microscope (TEM). Magnetic saturation of synthesized magnetite nanoparticles are reduced from 46.94 to 11.98 emu/g after coating with gold. The performance of the proposed optical-thermal modeling technique is verified by simulation and experimental results. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. [Navigated drilling for femoral head necrosis. Experimental and clinical results].

    PubMed

    Beckmann, J; Tingart, M; Perlick, L; Lüring, C; Grifka, J; Anders, S

    2007-05-01

    In the early stages of osteonecrosis of the femoral head, core decompression by exact drilling into the ischemic areas can reduce pain and achieve reperfusion. Using computer aided surgery, the precision of the drilling can be improved while simultaneously lowering radiation exposure time for both staff and patients. We describe the experimental and clinical results of drilling under the guidance of the fluoroscopically-based VectorVision navigation system (BrainLAB, Munich, Germany). A total of 70 sawbones were prepared mimicking an osteonecrosis of the femoral head. In two experimental models, bone only and obesity, as well as in a clinical setting involving ten patients with osteonecrosis of the femoral head, the precision and the duration of radiation exposure were compared between the VectorVision system and conventional drilling. No target was missed. For both models, there was a statistically significant difference in terms of the precision, the number of drilling corrections as well as the radiation exposure time. The average distance to the desired midpoint of the lesion of both models was 0.48 mm for navigated drilling and 1.06 mm for conventional drilling, the average drilling corrections were 0.175 and 2.1, and the radiation exposure time less than 1 s and 3.6 s, respectively. In the clinical setting, the reduction of radiation exposure (below 1 s for navigation compared to 56 s for the conventional technique) as well as of drilling corrections (0.2 compared to 3.4) was also significant. Computer guided drilling using the fluoroscopically based VectorVision navigation system shows a clearly improved precision with a enormous simultaneous reduction in radiation exposure. It is therefore recommended for clinical routine.

  7. Experimental results for correlation-based wavefront sensing

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Poyneer, L A; Palmer, D W; LaFortune, K N

    2005-07-01

    Correlation wave-front sensing can improve Adaptive Optics (AO) system performance in two keys areas. For point-source-based AO systems, Correlation is more accurate, more robust to changing conditions and provides lower noise than a centroiding algorithm. Experimental results from the Lick AO system and the SSHCL laser AO system confirm this. For remote imaging, Correlation enables the use of extended objects for wave-front sensing. Results from short horizontal-path experiments will show algorithm properties and requirements.

  8. Accelerating Mathematics Achievement Using Heterogeneous Grouping

    ERIC Educational Resources Information Center

    Burris, Carol Corbett; Heubert, Jay P.; Levin, Henry M.

    2006-01-01

    This longitudinal study examined the effects of providing an accelerated mathematics curriculum in heterogeneously grouped middle school classes in a diverse suburban school district. A quasi-experimental cohort design was used to evaluate subsequent completion of advanced high school math courses as well as academic achievement. Results showed…

  9. A quasi-experimental study of maternal smoking during pregnancy and offspring academic achievement

    PubMed Central

    D'Onofrio, Brian M.; Singh, Amber L.; Iliadou, Anastasia; Lambe, Mats; Hultman, Christina M.; Neiderhiser, Jenae M.; Långström, Niklas; Lichtenstein, Paul

    2013-01-01

    Maternal smoking during pregnancy (SDP) is associated with lower academic achievement in offspring. The current study, which was based on all births in Sweden from 1983 through 1991, explored the possible causal processes underlying the association between SDP and offspring school grades and a standardized assessment of mathematic proficiency at age 15. The analyses compared relatives who varied in their exposure to SDP and who varied in their genetic relatedness. Although SDP was statistically associated with academic achievement when comparing unrelated individuals, the results suggest that SDP does not cause poorer academic performance, as full siblings differentially exposed to SDP did not differ in their academic scores. The pattern of results suggests that genetic factors shared by parents and their offspring explain significant variance in why offspring opposed to SDP have lower levels of academic achievement. Nevertheless, SDP impacts pregnancy-related outcomes. Reducing SDP, therefore, remains a major public health issue. PMID:20331655

  10. Methods of experimentation with models and utilization of results

    NASA Technical Reports Server (NTRS)

    Robert,

    1924-01-01

    The present report treats the subject of testing small models in a wind tunnel and of the methods employed for rendering the results constant, accurate and comparable with one another. Detailed experimental results are given.

  11. Hydrocarbon-Fueled Rocket Engine Plume Diagnostics: Analytical Developments and Experimental Results

    NASA Technical Reports Server (NTRS)

    Tejwani, Gopal D.; McVay, Gregory P.; Langford, Lester A.; St. Cyr, William W.

    2006-01-01

    A viewgraph presentation describing experimental results and analytical developments about plume diagnostics for hydrocarbon-fueled rocket engines is shown. The topics include: 1) SSC Plume Diagnostics Background; 2) Engine Health Monitoring Approach; 3) Rocket Plume Spectroscopy Simulation Code; 4) Spectral Simulation for 10 Atomic Species and for 11 Diatomic Molecular Electronic Bands; 5) "Best" Lines for Plume Diagnostics for Hydrocarbon-Fueled Rocket Engines; 6) Experimental Set Up for the Methane Thruster Test Program and Experimental Results; and 7) Summary and Recommendations.

  12. On collisional disruption - Experimental results and scaling laws

    NASA Technical Reports Server (NTRS)

    Davis, Donald R.; Ryan, Eileen V.

    1990-01-01

    Both homogeneous and inhomogeneous targets have been addressed by the present experimental consideration of the impact strengths, fragment sizes, and fragment velocities generated by cement mortar targets whose crushing strengths vary by an order of magnitude, upon impact of projectiles in the velocity range of 50-5700 m/sec. When combined with additional published data, dynamic impact strength is found to correlate with quasi-static material strengths for materials ranging in character from basalt to ice; two materials not following this trend, however, are weak mortar and clay targets. Values consistent with experimental results are obtainable with a simple scaling algorithm based on impact energy, material properties, and collisional strain rate.

  13. How to Achieve Better Results Using Pass-Based Virtual Screening: Case Study for Kinase Inhibitors

    NASA Astrophysics Data System (ADS)

    Pogodin, Pavel V.; Lagunin, Alexey A.; Rudik, Anastasia V.; Filimonov, Dmitry A.; Druzhilovskiy, Dmitry S.; Nicklaus, Mark C.; Poroikov, Vladimir V.

    2018-04-01

    Discovery of new pharmaceutical substances is currently boosted by the possibility of utilization of the Synthetically Accessible Virtual Inventory (SAVI) library, which includes about 283 million molecules, each annotated with a proposed synthetic one-step route from commercially available starting materials. The SAVI database is well-suited for ligand-based methods of virtual screening to select molecules for experimental testing. In this study, we compare the performance of three approaches for the analysis of structure-activity relationships that differ in their criteria for selecting of “active” and “inactive” compounds included in the training sets. PASS (Prediction of Activity Spectra for Substances), which is based on a modified Naïve Bayes algorithm, was applied since it had been shown to be robust and to provide good predictions of many biological activities based on just the structural formula of a compound even if the information in the training set is incomplete. We used different subsets of kinase inhibitors for this case study because many data are currently available on this important class of drug-like molecules. Based on the subsets of kinase inhibitors extracted from the ChEMBL 20 database we performed the PASS training, and then applied the model to ChEMBL 23 compounds not yet present in ChEMBL 20 to identify novel kinase inhibitors. As one may expect, the best prediction accuracy was obtained if only the experimentally confirmed active and inactive compounds for distinct kinases in the training procedure were used. However, for some kinases, reasonable results were obtained even if we used merged training sets, in which we designated as inactives the compounds not tested against the particular kinase. Thus, depending on the availability of data for a particular biological activity, one may choose the first or the second approach for creating ligand-based computational tools to achieve the best possible results in virtual screening.

  14. Note: Comparison experimental results of the laser heterodyne interferometer for angle measurement based on the Faraday effect.

    PubMed

    Zhang, Enzheng; Chen, Benyong; Zheng, Hao; Teng, Xueying; Yan, Liping

    2018-04-01

    A laser heterodyne interferometer for angle measurement based on the Faraday effect is proposed. A novel optical configuration, designed by using the orthogonal return method for a linearly polarized beam based on the Faraday effect, guarantees that the measurement beam can return effectively even though an angular reflector has a large lateral displacement movement. The optical configuration and measurement principle are presented in detail. Two verification experiments were performed; the experimental results show that the proposed interferometer can achieve a large lateral displacement tolerance of 7.4 mm and also can realize high precision angle measurement with a large measurement range.

  15. Note: Comparison experimental results of the laser heterodyne interferometer for angle measurement based on the Faraday effect

    NASA Astrophysics Data System (ADS)

    Zhang, Enzheng; Chen, Benyong; Zheng, Hao; Teng, Xueying; Yan, Liping

    2018-04-01

    A laser heterodyne interferometer for angle measurement based on the Faraday effect is proposed. A novel optical configuration, designed by using the orthogonal return method for a linearly polarized beam based on the Faraday effect, guarantees that the measurement beam can return effectively even though an angular reflector has a large lateral displacement movement. The optical configuration and measurement principle are presented in detail. Two verification experiments were performed; the experimental results show that the proposed interferometer can achieve a large lateral displacement tolerance of 7.4 mm and also can realize high precision angle measurement with a large measurement range.

  16. High Contrast Imaging in the Visible: First Experimental Results at the Large Binocular Telescope

    NASA Astrophysics Data System (ADS)

    Pedichini, F.; Stangalini, M.; Ambrosino, F.; Puglisi, A.; Pinna, E.; Bailey, V.; Carbonaro, L.; Centrone, M.; Christou, J.; Esposito, S.; Farinato, J.; Fiore, F.; Giallongo, E.; Hill, J. M.; Hinz, P. M.; Sabatini, L.

    2017-08-01

    In 2014 February, the System for High contrast And coronography from R to K at VISual bands (SHARK-VIS) Forerunner, a high contrast experimental imager operating at visible wavelengths, was installed at the Large Binocular Telescope (LBT). Here we report on the first results obtained by recent on-sky tests. These results show the extremely good performance of the LBT Extreme Adaptive Optics (ExAO) system at visible wavelengths, both in terms of spatial resolution and contrast achieved. Similarly to what was done by Amara & Quanz (2012), we used the SHARK-VIS Forerunner data to quantitatively assess the contrast enhancement. This is done by injecting several different synthetic faint objects in the acquired data and applying the angular differential imaging (ADI) technique. A contrast of the order of 5 × 10-5 is obtained at 630 nm for angular separations from the star larger than 100 mas. These results are discussed in light of the future development of SHARK-VIS and compared to those obtained by other high contrast imagers operating at similar wavelengths.

  17. Slit-scanning differential phase-contrast mammography: first experimental results

    NASA Astrophysics Data System (ADS)

    Roessl, Ewald; Daerr, Heiner; Koehler, Thomas; Martens, Gerhard; van Stevendaal, Udo

    2014-03-01

    The demands for a large field-of-view (FOV) and the stringent requirements for a stable acquisition geometry rank among the major obstacles for the translation of grating-based, differential phase-contrast techniques from the laboratory to clinical applications. While for state-of-the-art Full-Field-Digital Mammography (FFDM) FOVs of 24 cm x 30 cm are common practice, the specifications for mechanical stability are naturally derived from the detector pixel size which ranges between 50 and 100 μm. However, in grating-based, phasecontrast imaging, the relative placement of the gratings in the interferometer must be guaranteed to within micro-meter precision. In this work we report on first experimental results on a phase-contrast x-ray imaging system based on the Philips MicroDose L30 mammography unit. With the proposed approach we achieve a FOV of about 65 mm x 175 mm by the use of the slit-scanning technique. The demand for mechanical stability on a micrometer scale was relaxed by the specific interferometer design, i.e., a rigid, actuator-free mount of the phase-grating G1 with respect to the analyzer-grating G2 onto a common steel frame. The image acquisition and formation processes are described and first phase-contrast images of a test object are presented. A brief discussion of the shortcomings of the current approach is given, including the level of remaining image artifacts and the relatively inefficient usage of the total available x-ray source output.

  18. Experimental results from a laboratory-scale molten salt thermocline storage

    NASA Astrophysics Data System (ADS)

    Seubert, Bernhard; Müller, Ralf; Willert, Daniel; Fluri, Thomas

    2017-06-01

    Single-tank storage presents a valid option for cost reduction in thermal energy storage systems. For low-temperature systems with water as storage medium this concept is widely implemented and tested. For high-temperature systems very limited experimental data are publicly available. To improve this situation a molten salt loop for experimental testing of a single-tank storage prototype was designed and built at Fraunhofer ISE. The storage tank has a volume of 0.4 m3 or a maximum capacity of 72 kWhth. The maximum charging and discharging power is 60 kW, however, a bypass flow control system enables to operate the system also at a very low power. The prototype was designed to withstand temperatures up to 550 °C. A cascaded insulation with embedded heating cables can be used to reduce the effect of heat loss on the storage which is susceptible to edge effects due to its small size. During the first tests the operating temperatures were adapted to the conditions in systems with thermal oil as heat transfer fluid and a smaller temperature difference. A good separation between cold and hot fluid was achieved with temperature gradients of 95 K within 16 cm.

  19. Increasing Achievement by Focusing Grade-Level Teams on Improving Classroom Learning: A Prospective, Quasi-Experimental Study of Title I Schools

    ERIC Educational Resources Information Center

    Saunders, William M.; Goldenberg, Claude N.; Gallimore, Ronald

    2009-01-01

    The authors conducted a quasi-experimental investigation of effects on achievement by grade-level teams focused on improving learning. For 2 years (Phase 1), principals-only training was provided. During the final 3 years (Phase 2), school-based training was provided for principals and teacher leaders on stabilizing team settings and using…

  20. The impact of including children with intellectual disability in general education classrooms on the academic achievement of their low-, average-, and high-achieving peers.

    PubMed

    Sermier Dessemontet, Rachel; Bless, Gérard

    2013-03-01

    This study aimed at assessing the impact of including children with intellectual disability (ID) in general education classrooms with support on the academic achievement of their low-, average-, and high-achieving peers without disability. A quasi-experimental study was conducted with an experimental group of 202 pupils from classrooms with an included child with mild or moderate ID, and a control group of 202 pupils from classrooms with no included children with special educational needs (matched pairs sample). The progress of these 2 groups in their academic achievement was compared over a period of 1 school year. No significant difference was found in the progress of the low-, average-, or high-achieving pupils from classrooms with or without inclusion. The results suggest that including children with ID in primary general education classrooms with support does not have a negative impact on the progress of pupils without disability.

  1. DoSSiER: Database of scientific simulation and experimental results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wenzel, Hans; Yarba, Julia; Genser, Krzystof

    The Geant4, GeantV and GENIE collaborations regularly perform validation and regression tests for simulation results. DoSSiER (Database of Scientific Simulation and Experimental Results) is being developed as a central repository to store the simulation results as well as the experimental data used for validation. DoSSiER can be easily accessed via a web application. In addition, a web service allows for programmatic access to the repository to extract records in json or xml exchange formats. In this paper, we describe the functionality and the current status of various components of DoSSiER as well as the technology choices we made.

  2. DoSSiER: Database of scientific simulation and experimental results

    DOE PAGES

    Wenzel, Hans; Yarba, Julia; Genser, Krzystof; ...

    2016-08-01

    The Geant4, GeantV and GENIE collaborations regularly perform validation and regression tests for simulation results. DoSSiER (Database of Scientific Simulation and Experimental Results) is being developed as a central repository to store the simulation results as well as the experimental data used for validation. DoSSiER can be easily accessed via a web application. In addition, a web service allows for programmatic access to the repository to extract records in json or xml exchange formats. In this paper, we describe the functionality and the current status of various components of DoSSiER as well as the technology choices we made.

  3. Experimental investigations of recent anomalous results in superconductivity

    NASA Astrophysics Data System (ADS)

    Souw, Victor K.

    2000-12-01

    This thesis examines three recent anomalous results associated with irreversibility in type-II superconductivity: (1) The magnetic properties of the predicted superconductors LiBeH3 and Li2BeH 4, (2) the paramagnetic transition near T = Tc in Nb, and (3) a noise transition in a YBa2Cu3O7-delta thin film near the vortex-solid transition. The investigation of Li 2BeH4 and LiBeH3 was prompted by theoretical predictions of room-temperature superconductivity for Li2BeH4 and LiBeH3 and a recent report that Li2BeH4 showed magnetic irreversibilities similar to those of type-II superconductors. A modified experimental method is introduced in order to avoid artifacts due to background signals. The resulting data is suggestive of a superparamagnetic impurity from one of the reagents used in the synthesis and after subtracting this contribution, the temperature-dependent susceptibilities of Li2 BeH4 and LiBeH3 are estimated. However, no magnetic irreversibility suggestive of superconductivity is observed. The anomalous paramagnetic transition in Nb is intriguing because Nb does not share the d-wave order parameter symmetry often invoked to explain the phenomenon in other superconductors. A modified experimental method was developed in order to avoid instrumental artifacts known to produce a similar apparently paramagnetic response, but the results of this method indicate that the paramagnetic response is a physical property of the sample. Finally, a very sharp noise transition in a YBa2Cu3O7-delta thin film was found to be distinct from previously reported features in the voltage noise commonly associated with vortex fluctuations near the irreversibility line. In each of these three cases the examination of experimental techniques is an integral part of the investigation of novel vortex behavior near the onset of irreversibility.

  4. Clinical and experimental study of TMJ distraction: preliminary results.

    PubMed

    Festa, F; Galluccio, G

    1998-01-01

    A physiotherapeutic approach, with manual maneuvers and/or distraction appliances, is indicated in the treatment of temporomandibular joint disorders (TMDs) to prevent the progressive fibrosis of the muscle fibers. In this article, the authors report preliminary results of experimental and clinical studies conducted to assess the real effect of distraction in temporomandibular joint disorders. The experimental invivo studies confirmed the structural alteration due to compression and distraction on the capsular and condylar tissues. Clinical cases are reported to show the increase of the intraarticular vertical dimension, with a forward and downward movement of the condyles in a more physiologic condition.

  5. THE EFFECTS ON ACHIEVEMENT TEST RESULTS OF VARYING CONDITIONS OF EXPERIMENTAL ATMOSPHERE, NOTICE OF TEST, TEST ADMINISTRATION, AND TEST SCORING.

    ERIC Educational Resources Information Center

    GOODWIN, WILLIAM L.; AND OTHERS

    NULL HYPOTHESES WERE TESTED TO DETERMINE THE DIFFERENTIAL EFFECTS OF (1) EXPERIMENTAL ATMOSPHERE AND ABSENCE OF SAME, (2) NOTICE OF TEST (10 SCHOOL DAYS) AND NO NOTICE (1 SCHOOL DAY), (3) TEACHER ADMINISTRATION AND OUTSIDE ADMINISTRATION OF TESTS, AND (4) TEACHER SCORING AND OUTSIDE SCORING OF TESTS. SIXTH-GRADE CLASSES (N=64), EACH FROM A…

  6. Experimental results for a hypersonic nozzle/afterbody flow field

    NASA Technical Reports Server (NTRS)

    Spaid, Frank W.; Keener, Earl R.; Hui, Frank C. L.

    1995-01-01

    This study was conducted to experimentally characterize the flow field created by the interaction of a single-expansion ramp-nozzle (SERN) flow with a hypersonic external stream. Data were obtained from a generic nozzle/afterbody model in the 3.5 Foot Hypersonic Wind Tunnel at the NASA Ames Research Center, in a cooperative experimental program involving Ames and McDonnell Douglas Aerospace. The model design and test planning were performed in close cooperation with members of the Ames computational fluid dynamics (CFD) team for the National Aerospace Plane (NASP) program. This paper presents experimental results consisting of oil-flow and shadow graph flow-visualization photographs, afterbody surface-pressure distributions, rake boundary-layer measurements, Preston-tube skin-friction measurements, and flow field surveys with five-hole and thermocouple probes. The probe data consist of impact pressure, flow direction, and total temperature profiles in the interaction flow field.

  7. Mechanical properties of triaxially braided composites: Experimental and analytical results

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Foye, Raymond L.; Pastore, Christopher M.; Gowayed, Yasser A.

    1992-01-01

    This paper investigates the unnotched tensile properties of two-dimensional triaxial braid reinforced composites from both an experimental and analytical viewpoint. The materials are graphite fibers in an epoxy matrix. Three different reinforcing fiber architectures were considered. Specimens were cut from resin transfer molded (RTM) composite panels made from each braid. There were considerable differences in the observed elastic constants from different size strain gage and extensometer readings. Larger strain gages gave more consistent results and correlated better with the extensometer readings. Experimental strains correlated reasonably well with analytical predictions in the longitudinal, zero degree, fiber direction but not in the transverse direction. Tensile strength results were not always predictable even in reinforcing directions. Minor changes in braid geometry led to disproportionate strength variations. The unit cell structure of the triaxial braid was discussed with the assistence of computer analysis of the microgeometry. Photomicrographs of the braid geometry were used to improve upon the computer graphics representations of unit cells. These unit cells were used to predict the elastic moduli with various degrees of sophistication. The simple and the complex analyses were generally in agreement but none adequately matched the experimental results for all the braids.

  8. Mechanical properties of triaxially braided composites: Experimental and analytical results

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Foye, Raymond L.; Pastore, Christopher M.; Gowayed, Yasser A.

    1992-01-01

    The unnotched tensile properties of 2-D triaxial braid reinforced composites from both an experimental and an analytical viewpoint are studied. The materials are graphite fibers in an epoxy matrix. Three different reinforcing fiber architectures were considered. Specimens were cut from resin transfer molded (RTM) composite panels made from each braid. There were considerable differences in the observed elastic constants from different size strain gage and extensometer reading. Larger strain gages gave more consistent results and correlated better with the extensometer reading. Experimental strains correlated reasonably well with analytical predictions in the longitudinal, 0 degrees, fiber direction but not in the transverse direction. Tensile strength results were not always predictable even in reinforcing directions. Minor changes in braid geometry led to disproportionate strength variations. The unit cell structure of the triaxial braid was discussed with the assistance of computer analysis of the microgeometry. Photomicrographs of braid geometry were used to improve upon the computer graphics representations of unit cells. These unit cells were used to predict the elastic moduli with various degrees of sophistication. The simple and the complex analyses were generally in agreement but none adequately matched the experimental results for all the braids.

  9. Composite Failures: A Comparison of Experimental Test Results and Computational Analysis Using XFEM

    DTIC Science & Technology

    2016-09-30

    NUWC-NPT Technical Report 12,218 30 September 2016 Composite Failures: A Comparison of Experimental Test Results and Computational Analysis...A Comparison of Experimental Test Results and Computational Analysis Using XFEM 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...availability of measurement techniques, experimental testing of composite materials has largely outpaced the computational modeling ability, forcing

  10. Assessment Results and Student Achievement; a Correlation Study Regarding Ability Grouping

    ERIC Educational Resources Information Center

    Slonaker, Richard V.

    2013-01-01

    School leaders face increased pressure to identify instructional and administrative practices that increase student achievement. However, achievement gaps persist between disadvantaged and non-disadvantaged student groups. This study highlighted relationships between ability grouping and academic achievement in a suburban school district.…

  11. Examining Cultural Capital and Student Achievement: Results of a Meta-Analytic Review

    ERIC Educational Resources Information Center

    Tan, Cheng Yong

    2017-01-01

    This meta-analysis summarized the relationships between cultural capital and student achievement (155 effect sizes involving 685,393 K-12 students) published in education journals between 1981 and 2015. Results showed a small-to-medium overall mean effect size, and larger individual effect sizes for parental education and parental expectations…

  12. Computer Class Role Playing Games, an innovative teaching methodology based on STEM and ICT: first experimental results

    NASA Astrophysics Data System (ADS)

    Maraffi, S.

    2016-12-01

    Context/PurposeWe experienced a new teaching and learning technology: a Computer Class Role Playing Game (RPG) to perform educational activity in classrooms through an interactive game. This approach is new, there are some experiences on educational games, but mainly individual and not class-based. Gaming all together in a class, with a single scope for the whole class, it enhances peer collaboration, cooperative problem solving and friendship. MethodsTo perform the research we experimented the games in several classes of different degrees, acquiring specific questionnaire by teachers and pupils. Results Experimental results were outstanding: RPG, our interactive activity, exceed by 50% the overall satisfaction compared to traditional lessons or Power Point supported teaching. InterpretationThe appreciation of RPG was in agreement with the class level outcome identified by the teacher after the experimentation. Our work experience get excellent feedbacks by teachers, in terms of efficacy of this new teaching methodology and of achieved results. Using new methodology more close to the student point of view improves the innovation and creative capacities of learners, and it support the new role of teacher as learners' "coach". ConclusionThis paper presents the first experimental results on the application of this new technology based on a Computer game which project on a wall in the class an adventure lived by the students. The plots of the actual adventures are designed for deeper learning of Science, Technology, Engineering, Mathematics (STEM) and Social Sciences & Humanities (SSH). The participation of the pupils it's based on the interaction with the game by the use of their own tablets or smartphones. The game is based on a mixed reality learning environment, giving the students the feel "to be IN the adventure".

  13. Utilization of variation theory in the classroom: Effect on students' algebraic achievement and motivation

    NASA Astrophysics Data System (ADS)

    Jing, Ting Jing; Tarmizi, Rohani Ahmad; Bakar, Kamariah Abu; Aralas, Dalia

    2017-01-01

    This study investigates the effect of utilizing Variation Theory Based Strategy on students' algebraic achievement and motivation in learning algebra. The study used quasi-experimental non-equivalent control group research design and involved 56 Form Two (Secondary Two) students in two classes (28 in experimental group, 28 in control group) in Malaysia The first class of students went through algebra class taught with Variation Theory Based Strategy (VTBS) while the second class of students experienced conventional teaching strategy. The instruments used for the study were a 24-item Algebra Test and 36-item Instructional Materials Motivation Survey. Result from analysis of Covariance indicated that experimental group students achieved significantly better test scores than control group. Result of Multivariate Analysis of Variance also shows evidences of significant effect of VTBS on experimental students' overall motivation in all the five subscales; attention, relevance, confidence, and satisfaction. These results suggested the utilization of VTBS would improve students' learning in algebra.

  14. Higher Education Counts: Achieving Results. 2007 Executive Summary

    ERIC Educational Resources Information Center

    Connecticut Department of Higher Education (NJ1), 2007

    2007-01-01

    "Higher Education Counts" is the annual accountability report on Connecticut's system of higher education. Since 2000, the report has been the primary vehicle for reporting higher education's progress toward achieving six, statutorily-defined state goals: (1) To enhance student learning and promote academic excellence; (2) To join with…

  15. Higher Education Counts: Achieving Results, 2008. Executive Summary

    ERIC Educational Resources Information Center

    Connecticut Department of Higher Education (NJ1), 2008

    2008-01-01

    "Higher Education Counts" is the annual accountability report on Connecticut's system of higher education. Since 2000, the report has been the primary vehicle for reporting higher education's progress toward achieving six, statutorily-defined state goals: (1) To enhance student learning and promote academic excellence; (2) To join with…

  16. Higher Education Counts: Achieving Results. 2009 Executive Summary

    ERIC Educational Resources Information Center

    Connecticut Department of Higher Education (NJ1), 2009

    2009-01-01

    "Higher Education Counts" is the annual accountability report on Connecticut's system of higher education. Since 2000, the report has been the primary vehicle for reporting higher education's progress toward achieving six, statutorily-defined state goals: (1) To enhance student learning and promote academic excellence; (2) To join with…

  17. Full-Day Kindergarten Results in Significant Achievement Gains

    ERIC Educational Resources Information Center

    Raskin, Candace F.; Haar, Jean M.

    2009-01-01

    In 2004, after an in-depth review of student achievement data for over 4,000 students, the administration of a school district in southern Minnesota identified the following challenges: (1) above-state-average number of special education students; (2) increasing number of English as Second Language (ESL) students; (3) increasing number of students…

  18. Graders' Mathematics Achievement

    ERIC Educational Resources Information Center

    Bond, John B.; Ellis, Arthur K.

    2013-01-01

    The purpose of this experimental study was to investigate the effects of metacognitive reflective assessment instruction on student achievement in mathematics. The study compared the performance of 141 students who practiced reflective assessment strategies with students who did not. A posttest-only control group design was employed, and results…

  19. Results achieved by emergency physicians in teaching basic cardiopulmonary resuscitation to secondary school students.

    PubMed

    Jiménez-Fábrega, Xavier; Escalada-Roig, Xavier; Sánchez, Miquel; Culla, Alexandre; Díaz, Núria; Gómez, Xavier; Villena, Olga; Rodríguez, Esther; Gaspar, Alberto; Molina, José Emilio; Salvador, Jordi; Miró, Oscar

    2009-06-01

    We investigated the results obtained with a basic cardiopulmonary resuscitation (b-CPR) program (PROCES) specifically designed for secondary school students (14-16 years old) and taught by emergency physicians. We used a multiple-choice test with 20 questions (10 on theory and 10 on skills) answered before and immediately after and 1 year after receiving the b-CPR course. Satisfactory learning was considered when at least 8 out of 10 skill questions were correctly answered. We investigated student variables associated with better immediate and deferred (1 year after) PROCES performance. We compared the results with those obtained using a more standardized program to teach b-CPR to police cadets. We enrolled 600 high school students. PROCES achieved significant improvement in overall, theory and skill marks immediately after the course (P<0.001), with a significant decay in all of them 1 year after the course (P<0.001). Satisfactory learning was achieved by 57% of school students immediately after PROCES and by 37% when assessed 1 year later. Students without pending study subjects (P=0.001) and those from private schools (P<0.01) achieved significantly better performance immediately after PROCES and only female students achieved greater performance 1 year after the course (P<0.05). With respect to police cadets instructed through a standardized course, immediate satisfactory learning of school students was lower (79 vs. 57%, respectively; P<0.001), whereas deferred satisfactory learning was higher (23 vs. 37%, respectively; P<0.05). Emergency physicians can satisfactorily instruct secondary school students in b-CPR using PROCES, and this specific program achieves a reasonable amount of satisfactory learning.

  20. Exemplar pediatric collaborative improvement networks: achieving results.

    PubMed

    Billett, Amy L; Colletti, Richard B; Mandel, Keith E; Miller, Marlene; Muething, Stephen E; Sharek, Paul J; Lannon, Carole M

    2013-06-01

    A number of pediatric collaborative improvement networks have demonstrated improved care and outcomes for children. Regionally, Cincinnati Children's Hospital Medical Center Physician Hospital Organization has sustained key asthma processes, substantially increased the percentage of their asthma population receiving "perfect care," and implemented an innovative pay-for-performance program with a large commercial payor based on asthma performance measures. The California Perinatal Quality Care Collaborative uses its outcomes database to improve care for infants in California NICUs. It has achieved reductions in central line-associated blood stream infections (CLABSI), increased breast-milk feeding rates at hospital discharge, and is now working to improve delivery room management. Solutions for Patient Safety (SPS) has achieved significant improvements in adverse drug events and surgical site infections across all 8 Ohio children's hospitals, with 7700 fewer children harmed and >$11.8 million in avoided costs. SPS is now expanding nationally, aiming to eliminate all events of serious harm at children's hospitals. National collaborative networks include ImproveCareNow, which aims to improve care and outcomes for children with inflammatory bowel disease. Reliable adherence to Model Care Guidelines has produced improved remission rates without using new medications and a significant increase in the proportion of Crohn disease patients not taking prednisone. Data-driven collaboratives of the Children's Hospital Association Quality Transformation Network initially focused on CLABSI in PICUs. By September 2011, they had prevented an estimated 2964 CLABSI, saving 355 lives and $103,722,423. Subsequent improvement efforts include CLABSI reductions in additional settings and populations.

  1. Correlation of analytical and experimental hot structure vibration results

    NASA Technical Reports Server (NTRS)

    Kehoe, Michael W.; Deaton, Vivian C.

    1993-01-01

    High surface temperatures and temperature gradients can affect the vibratory characteristics and stability of aircraft structures. Aircraft designers are relying more on finite-element model analysis methods to ensure sufficient vehicle structural dynamic stability throughout the desired flight envelope. Analysis codes that predict these thermal effects must be correlated and verified with experimental data. Experimental modal data for aluminum, titanium, and fiberglass plates heated at uniform, nonuniform, and transient heating conditions are presented. The data show the effect of heat on each plate's modal characteristics, a comparison of predicted and measured plate vibration frequencies, the measured modal damping, and the effect of modeling material property changes and thermal stresses on the accuracy of the analytical results at nonuniform and transient heating conditions.

  2. Experimental Results for Titan Aerobot Thermo-Mechanical Subsystem Development

    NASA Technical Reports Server (NTRS)

    Pauken, Michael T.; Hall, Jeffery L.

    2006-01-01

    This paper presents experimental results on a set of 4 thermo-mechanical research tasks aimed at Titan and Venus aerobots: 1. A cryogenic balloon materials development program culminating in the fabrication and testing of a 4.6 m long blimp prototype at 93K. 2. A combined computational and experimental thermal analysis of the effect of radioisotope power system (RPS) waste heat on the behavior of a helium filled blimp hull. 3. Aerial deployment and inflation testing using a blimp 4. A proof of concept experiment with an aerobot-mounted steerable high gain antenna These tasks were supported with JPL internal R&D funds and executed by JPL engineers with substantial industry collaboration for Task #1, the cryogenic balloon materials

  3. [Multi-channel motion signal acquisition system and experimental results].

    PubMed

    Zhong, Sheng; Yi, Wanguan; Deng, Ke; Zhan, Kai; Wen, Huiying; Chen, Xin

    2014-09-01

    For the study of muscle function and features during exercise, a multi-channel data acquisition system was developed, the overall design of the system, hardware composition, the function of system and so on have made a detail implements. The synchronous acquisition and storage of the surface EMG signal, joint angle signal, plantar pressure signal, ultrasonic image and initial results have been achieved.

  4. Experimental and computational results from a large low-speed centrifugal impeller

    NASA Technical Reports Server (NTRS)

    Hathaway, M. D.; Chriss, R. M.; Wood, J. R.; Strazisar, A. J.

    1993-01-01

    An experimental and computational investigation of the NASA Low-Speed Centrifugal Compressor (LSCC) flow field has been conducted using laser anemometry and Dawes' 3D viscous code. The experimental configuration consists of a backswept impeller followed by a vaneless diffuser. Measurements of the three-dimensional velocity field were acquired at several measurement planes through the compressor. The measurements describe both the throughflow and secondary velocity field along each measurement plane and in several cases provide details of the flow within the blade boundary layers. The experimental and computational results provide a clear understanding of the development of the throughflow momentum wake which is characteristic of centrifugal compressors.

  5. Next Generation Scientists, Next Opportunities: EPA's Science To Achieve Results (STAR) Program

    NASA Astrophysics Data System (ADS)

    Jones, M.

    2004-12-01

    Scientific research is one of the most powerful tools we have for understanding and protecting our environment. It provides the foundation for what we know about our planet, how it has changed, and how it could be altered in the future. The National Center for Environmental Research (NCER) in the U.S. Environmental Protection Agency's (EPA) Office of Research and Development (ORD) supports high-quality, extramural research by the nation's leading scientists and engineers to strengthen the basis for decisions about local and national environmental issues. NCER works with academia, state and local governments, other federal agencies, and scientists in EPA to increase human knowledge of how to protect our health and natural resources through its three major programs: · Science to Achieve Results (STAR) Grants · Small Business Innovative Research (SBIR) · Science to Achieve Results (STAR) Fellowships STAR, NCER's primary program, funds research grants and graduate fellowships in environmental science and engineering. Developing the next generation of environmental scientists and engineers is one of NCER's most important objectives. Each year, NCER helps between 80 and 160 students achieve Master's or Ph.D. degrees in environmental science and engineering through its STAR and Greater Research Opportunities (GRO) fellowships. Some of these students have moved on to careers in government while others are now full-time professors and researchers. Still others are working for state environmental agencies or furthering their studies through postdoctoral positions at universities. Since the inception of the NCER program, STAR fellowships (along with grants and SBIR projects) have been awarded in every state in the country. With the help of STAR, current and future scientists and engineers have been able to explore ways to preserve and protect human health and our precious resources.

  6. Control of Warm Compression Stations Using Model Predictive Control: Simulation and Experimental Results

    NASA Astrophysics Data System (ADS)

    Bonne, F.; Alamir, M.; Bonnay, P.

    2017-02-01

    This paper deals with multivariable constrained model predictive control for Warm Compression Stations (WCS). WCSs are subject to numerous constraints (limits on pressures, actuators) that need to be satisfied using appropriate algorithms. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to achieve precise control of pressures in normal operation or to avoid reaching stopping criteria (such as excessive pressures) under high disturbances (such as a pulsed heat load expected to take place in future fusion reactors, expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details the simulator used to validate this new control scheme and the associated simulation results on the SBTs WCS. This work is partially supported through the French National Research Agency (ANR), task agreement ANR-13-SEED-0005.

  7. Preliminary experimental results of tungsten wire-array Z-pinches on primary test stand

    NASA Astrophysics Data System (ADS)

    Huang, Xian-Bin; Zhou, Shao-Tong; Dan, Jia-Kun; Ren, Xiao-Dong; Wang, Kun-Lun; Zhang, Si-Qun; Li, Jing; Xu, Qiang; Cai, Hong-Chun; Duan, Shu-Chao; Ouyang, Kai; Chen, Guang-Hua; Ji, Ce; Wei, Bing; Feng, Shu-Ping; Wang, Meng; Xie, Wei-Ping; Deng, Jian-Jun; Zhou, Xiu-Wen; Yang, Yi

    2015-07-01

    The Primary Test Stand (PTS) developed at the China Academy of Engineering Physics is a 20 TW pulsed power driver, which can deliver a ˜10 MA, 70 ns rise-time (10%-90%) current to a short-circuit load and has important applications in Z-pinch driven inertial confinement fusion and high energy density physics. Preliminary results of tungsten wire-array Z-pinch experiments on PTS are presented. The load geometries investigated include 15-mm-tall cylindrical single and nested arrays with diameter ranging from 13 mm to 30 mm, consisting of 132-300 tungsten wires with 5-10 μm in diameter. Multiple diagnostics were fielded to characterize the x-ray radiation from wire-array Z pinches. The x-ray peak power (˜50 TW) and total radiated energy (˜500 kJ) were obtained from a single 20-mm-diam array with 80-ns stagnation time. The highest x-ray peak power up to 80 TW with 2.4 ns FWHM was achieved by using a nested array with 20-mm outer diameter, and the total x-ray energy from the nested array is comparable to that of single array. Implosion velocity estimated from the time-resolved image measurement exceeds 30 cm/μs. The detailed experimental results and other findings are presented and discussed.

  8. A Quasi-Experimental Study on Using Short Stories: Statistical and Inferential Analyses on the Non-English Major University Students' Speaking and Writing Achievements

    ERIC Educational Resources Information Center

    Iman, Jaya Nur

    2017-01-01

    This research was conducted to find out whether or not using short stories significantly improve the speaking and writing achievements. A quasi-experimental study of non-equivalent pretest-posttest control group design or comparison group design was used in this research. The population of this research was the all first semester undergraduate…

  9. Experimental results on current-driven turbulence in plasmas - a survey

    NASA Astrophysics Data System (ADS)

    de Kluiver, H.; Perepelkin, N. F.; Hirose, A.

    1991-01-01

    The experimental consequences of plasma turbulence driven by a current parallel to a magnetic field and concurrent anomalous plasma heating are reviewed, with an attempt to deduce universalities in key parameters such as the anomalous electrical conductivities observed in diverse devices. It has been found that the nature of plasma turbulence and turbulent heating depends on several parameters including the electric field, current and magnetic fields. A classification of turbulence regimes based on these parameters has been made. Experimental observations of the anomalous electrical conductivity, plasma heating, skin effect, runaway electron braking and turbulent fluctuations are surveyed, and current theoretical understanding is briefly reviewed. Experimental results recently obtained in stellarators (SIRIUS, URAGAN at Kharkov), and in tokamaks (TORTUR at Nieuwegein, STOR-1M at Saskatoon) are presented in some detail in the light of investigating the feasibility of using turbulent heating as a means of injecting a large power into toroidal devices.

  10. Testing for Results: Helping Families, Schools and Communities Understand and Improve Student Achievement.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Office of the Under Secretary.

    Redefining the federal government's role in kindergarten through grade 12 education, the No Child Left Behind Act of 2001 is designed to close the achievement gap between disadvantaged and minority students and their peers. The act is based on four principles, the first of which is stronger accountability for results, entailing creation of…

  11. Experimental and computational surface and flow-field results for an all-body hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Lockman, William K.; Lawrence, Scott L.; Cleary, Joseph W.

    1990-01-01

    The objective of the present investigation is to establish a benchmark experimental data base for a generic hypersonic vehicle shape for validation and/or calibration of advanced computational fluid dynamics computer codes. This paper includes results from the comprehensive test program conducted in the NASA/Ames 3.5-foot Hypersonic Wind Tunnel for a generic all-body hypersonic aircraft model. Experimental and computational results on flow visualization, surface pressures, surface convective heat transfer, and pitot-pressure flow-field surveys are presented. Comparisons of the experimental results with computational results from an upwind parabolized Navier-Stokes code developed at Ames demonstrate the capabilities of this code.

  12. Effect of Peer-Led Team Learning (PLTL) on Student Achievement, Attitude, and Self-Concept in College General Chemistry in Randomized and Quasi Experimental Designs

    ERIC Educational Resources Information Center

    Chan, Julia Y. K.; Bauer, Christopher F.

    2015-01-01

    This study investigated exam achievement and affective characteristics of students in general chemistry in a fully-randomized experimental design, contrasting Peer-Led Team Learning (PLTL) participation with a control group balanced for time-on-task and study activity. This study population included two independent first-semester courses with…

  13. A Review of Out-of-School Time Program Quasi-Experimental and Experimental Evaluation Results. Out-of-School Time Evaluation Snapshot.

    ERIC Educational Resources Information Center

    Little, Priscilla M. D.; Harris, Erin

    As the amount of resources allocated to out-of-school (OST) programming and policymakers' demands for research-based results increase, there is increasing interest in rigorous research designs to examine OST program outcomes. This issue of "Out-of-School Time Evaluation Snapshots" reviews 27 quasi-experimental and experimental OST…

  14. Promoting Creative Thinking Ability Using Contextual Learning Model in Technical Drawing Achievement

    NASA Astrophysics Data System (ADS)

    Mursid, R.

    2018-02-01

    The purpose of this study is to determine whether there is influence; the differences in the results between students that learn drawing techniques taught by the Contextual Innovative Model (CIM) and taught by Direct Instructional Model (DIM), the differences in achievement among students of technical drawing that have High Creative Thinking Ability (HCTA) with Low Creative Thinking Ability (LCTA), and the interaction between the learning model with the ability to think creatively to the achievement technical drawing. Quasi-experimental research method. Results of research appoint that: the achievement of students that learned technical drawing by using CIM is higher than the students that learned technical drawing by using DIM, the achievement of students of technical drawings HCTA is higher than the achievement of students who have technical drawing LCTA, and there are interactions between the use of learning models and creative thinking abilities in influencing student achievement technical drawing.

  15. Sensitivity Analysis of Different Shapes of a Plastic Optical Fiber-Based Immunosensor for Escherichia coli: Simulation and Experimental Results.

    PubMed

    Rodrigues, Domingos M C; Lopes, Rafaela N; Franco, Marcos A R; Werneck, Marcelo M; Allil, Regina C S B

    2017-12-19

    Conventional pathogen detection methods require trained personnel, specialized laboratories and can take days to provide a result. Thus, portable biosensors with rapid detection response are vital for the current needs for in-loco quality assays. In this work the authors analyze the characteristics of an immunosensor based on the evanescent field in plastic optical fibers with macro curvature by comparing experimental with simulated results. The work studies different shapes of evanescent-wave based fiber optic sensors, adopting a computational modeling to evaluate the probes with the best sensitivity. The simulation showed that for a U-Shaped sensor, the best results can be achieved with a sensor of 980 µm diameter by 5.0 mm in curvature for refractive index sensing, whereas the meander-shaped sensor with 250 μm in diameter with radius of curvature of 1.5 mm, showed better sensitivity for either bacteria and refractive index (RI) sensing. Then, an immunosensor was developed, firstly to measure refractive index and after that, functionalized to detect Escherichia coli . Based on the results with the simulation, we conducted studies with a real sensor for RI measurements and for Escherichia coli detection aiming to establish the best diameter and curvature radius in order to obtain an optimized sensor. On comparing the experimental results with predictions made from the modelling, good agreements were obtained. The simulations performed allowed the evaluation of new geometric configurations of biosensors that can be easily constructed and that promise improved sensitivity.

  16. Electrical and thermal behavior of unsaturated soils: experimental results

    NASA Astrophysics Data System (ADS)

    Nouveau, Marie; Grandjean, Gilles; Leroy, Philippe; Philippe, Mickael; Hedri, Estelle; Boukcim, Hassan

    2016-05-01

    When soil is affected by a heat source, some of its properties are modified, and in particular, the electrical resistivity due to changes in water content. As a result, these changes affect the thermal properties of soil, i.e., its thermal conductivity and diffusivity. We experimentally examine the changes in electrical resistivity and thermal conductivity for four soils with different grain size distributions and clay content over a wide range of temperatures, from 20 to 100 °C. This temperature range corresponds to the thermal conditions in the vicinity of a buried high voltage cable or a geothermal system. Experiments were conducted at the field scale, at a geothermal test facility, and in the laboratory using geophysical devices and probing systems. The results show that the electrical resistivity decreases and the thermal conductivity increases with temperature up to a critical temperature depending on soil types. At this critical temperature, the air volume in the pore space increases with temperature, and the resulting electrical resistivity also increases. For higher temperatures , the thermal conductivity increases sharply with temperature up to a second temperature limit. Beyond it, the thermal conductivity drops drastically. This limit corresponds to the temperature at which most of the water evaporates from the soil pore space. Once the evaporation is completed, the thermal conductivity stabilizes. To explain these experimental results, we modeled the electrical resistivity variations with temperature and water content in the temperature range 20 - 100°C, showing that two critical temperatures influence the main processes occurring during heating at temperatures below 100 °C.

  17. Advanced Supersonic Nozzle Concepts: Experimental Flow Visualization Results Paired With LES

    NASA Astrophysics Data System (ADS)

    Berry, Matthew; Magstadt, Andrew; Stack, Cory; Gaitonde, Datta; Glauser, Mark; Syracuse University Team; The Ohio State University Team

    2015-11-01

    Advanced supersonic nozzle concepts are currently under investigation, utilizing multiple bypass streams and airframe integration to bolster performance and efficiency. This work focuses on the parametric study of a supersonic, multi-stream jet with aft deck. The single plane of symmetry, rectangular nozzle, displays very complex and unique flow characteristics. Flow visualization techniques in the form of PIV and schlieren capture flow features at various deck lengths and Mach numbers. LES is compared to the experimental results to both validate the computational model and identify limitations of the simulation. By comparing experimental results to LES, this study will help create a foundation of knowledge for advanced nozzle designs in future aircraft. SBIR Phase II with Spectral Energies, LLC under direction of Barry Kiel.

  18. The Effects of CSCOPE on Student Achievement as Measured by Both TAKS and STAAR Test Results

    ERIC Educational Resources Information Center

    Helm, Maricela Robledo

    2013-01-01

    The purpose of this study was to examine the effects of CSCOPE curriculum on student achievement. CSCOPE is a curriculum management system used in 750 of the 1,039 school districts in the state of Texas. Student achievement is based on the results acquired from the Texas Assessment of Knowledge and Skills (TAKS) and the new version of the state…

  19. Refractive Errors and Academic Achievements of Primary School Children.

    PubMed

    Joseph, Lucyamma

    2014-01-01

    The current study was conducted among school children of selected schools of Thiruvananthapuram district of Kerala. It was designed to investigate the effect of refractive errors on academic achievement of primary school children. Experimental method was used in the study and the study used a sample of 185 children. An equated sample without myopia were selected as control group. Academic achievement tests based on the study syllabus were prepared and administered to both groups. The children with myopia were given corrective devices such as glasses prescribed by the ophthalmologist. After five months academic achievement tests were again given to both groups and the results of the scores between two groups as well as the scores before and after correction of errors were compared, which showed a significant influence of myopia on academic achievement and examination anxiety of children.

  20. Experimental results in evolutionary fault-recovery for field programmable analog devices

    NASA Technical Reports Server (NTRS)

    Zebulum, Ricardo S.; Keymeulen, Didier; Duong, Vu; Guo, Xin; Ferguson, M. I.; Stoica, Adrian

    2003-01-01

    This paper presents experimental results of fast intrinsic evolutionary design and evolutionary fault recovery of a 4-bit Digital to Analog Converter (DAC) using the JPL stand-alone board-level evolvable system (SABLES).

  1. Experimental results on the enhanced backscatter phenomenon and its dynamics

    NASA Astrophysics Data System (ADS)

    Wu, Chensheng; Nelson, William; Ko, Jonathan; Davis, Christopher C.

    2014-10-01

    Enhanced backscatter effects have long been predicted theoretically and experimentally demonstrated. The reciprocity of a turbulent channel generates a group of paired rays with identical trajectory and phase information that leads to a region in phase space with double intensity and scintillation index. Though simulation work based on phase screen models has demonstrated the existence of the phenomenon, few experimental results have been published describing its characteristics, and possible applications of the enhanced backscatter phenomenon are still unclear. With the development of commercially available high powered lasers and advanced cameras with high frame rates, we have successfully captured the enhanced backscatter effects from different reflection surfaces. In addition to static observations, we have also tilted and pre-distorted the transmitted beam at various frequencies to track the dynamic properties of the enhanced backscatter phenomenon to verify its possible application in guidance and beam and image correction through atmospheric turbulence. In this paper, experimental results will be described, and discussions on the principle and applications of the phenomenon will be included. Enhanced backscatter effects are best observed in certain levels of turbulence (Cn 2≍10-13 m-2/3), and show significant potential for providing self-guidance in beam correction that doesn't introduce additional costs (unlike providing a beacon laser). Possible applications of this phenomenon include tracking fast moving object with lasers, long distance (>1km) alignment, and focusing a high-power corrected laser beam over long distances.

  2. The effect of inquiry-flipped classroom model toward students' achievement on chemical reaction rate

    NASA Astrophysics Data System (ADS)

    Paristiowati, Maria; Fitriani, Ella; Aldi, Nurul Hanifah

    2017-08-01

    The aim of this research is to find out the effect of Inquiry-Flipped Classroom Models toward Students' Achievement on Chemical Reaction Rate topic. This study was conducted at SMA Negeri 3 Tangerang in Eleventh Graders. The Quasi Experimental Method with Non-equivalent Control Group design was implemented in this study. 72 students as the sample was selected by purposive sampling. Students in experimental group were learned through inquiry-flipped classroom model. Meanwhile, in control group, students were learned through guided inquiry learning model. Based on the data analysis, it can be seen that there is significant difference in the result of the average achievement of the students. The average achievement of the students in inquiry-flipped classroom model was 83,44 and the average achievement of the students in guided inquiry learning model was 74,06. It can be concluded that the students' achievement with inquiry-flipped classroom better than guided inquiry. The difference of students' achievement were significant through t-test which is tobs 3.056 > ttable 1.994 (α = 0.005).

  3. Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

    NASA Technical Reports Server (NTRS)

    Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

    2013-01-01

    results from integrating the VCHP with an operating Stirling convertor and describes the methodology used to achieve their successful combined operation.

  4. Alkali Metal Backup Cooling for Stirling Systems - Experimental Results

    NASA Technical Reports Server (NTRS)

    Schwendeman, Carl; Tarau, Calin; Anderson, William G.; Cornell, Peggy A.

    2013-01-01

    results from integrating the VCHP with an operating Stirling convertor and describes the methodology used to achieve their successful combined operation.

  5. Analytical, Numerical, and Experimental Results on Turbulent Boundary Layers

    DTIC Science & Technology

    1976-07-01

    a pitot pressure rake where the spacing between probe centers was 0.5 in. near the wall and 1.0 in. away from the wall. Recently, measurements have...Pressure Gradient, Part II. Analysis- of the Experimental Data." BRL R 1543, June 1971. 51. Allen, J. M. " Pitot -Probe Displacement in a Supersonic Turbulent...numbers; (4) a description of the data reduction of pitot pressure measurements utilizing these analytical results in order to obtain velocity

  6. Student Involvement in Learning and School Achievement.

    ERIC Educational Resources Information Center

    Anderson, Lorin W.

    The purpose of the study was to investigate the relationship between selected student characteristics, student involvement in learning, and achievement. Both naturalistic (n = 28, 27) and experimental studies were conducted. In the experimental study, two classes (n = 29, 26) learned a sequence of matrix arithmetic by mastery learning strategies.…

  7. Closed Loop Two-Phase Thermosyphon of Small Dimensions: a Review of the Experimental Results

    NASA Astrophysics Data System (ADS)

    Franco, Alessandro; Filippeschi, Sauro

    2012-06-01

    A bibliographical review on the heat and mass transfer in gravity assisted Closed Loop Two Phase Thermosyphons (CLTPT) with channels having a hydraulic diameter of the order of some millimetres and input power below 1 kW is proposed. The available experimental works in the literature are critically analysed in order to highlight the main results and the correlation between mass flow rate and heat input in natural circulation loops. A comparison of different experimental apparatuses and results is made. It is observed that the results are very different among them and in many cases the experimental data disagree with the conventional theory developed for an imposed flow rate. The paper analyses the main differences among the experimental devices and try to understand these disagreements. From the present analysis it is evident that further systematic studies are required to generate a meaningful body of knowledge of the heat and mass transport mechanism in these devices for practical applications in cooling devices or energy systems.

  8. An experimental/computational study of sharp fin induced shock wave/turbulent boundary layer interactions at Mach 5 - Experimental results

    NASA Technical Reports Server (NTRS)

    Rodi, Patrick E.; Dolling, David S.

    1992-01-01

    A combined experimental/computational study has been performed of sharp fin induced shock wave/turbulent boundary layer interactions at Mach 5. The current paper focuses on the experiments and analysis of the results. The experimental data include mean surface heat transfer, mean surface pressure distributions and surface flow visualization for fin angles of attack of 6, 8, 10, 12, 14 and 16-degrees at Mach 5 under a moderately cooled wall condition. Comparisons between the results and correlations developed earlier show that Scuderi's correlation for the upstream influence angle (recast in a conical form) is superior to other such correlations in predicting the current results, that normal Mach number based correlations for peak pressure heat transfer are adequate and that the initial heat transfer peak can be predicted using pressure-interaction theory.

  9. The Value of Full Correction: Achieving Excellent and Affordable Results.

    PubMed

    Kaplan, Julie Bass

    2016-01-01

    Patients often come to medical aesthetic offices with hopes to fully correct lost facial volume and achieve a natural appearance. Unfortunately, the cost per syringe of dermal filler can be a barrier to desired outcomes. Many aesthetic practitioners do the best they can with the amount of product the patient can afford, often falling short of the "wow" effect for the patient. This article describes what one office implemented to solve the conundrum of affordability while still allowing offices to cover its own financial realities. This tool can help patients achieve beautiful, natural, and affordable outcomes while helping offices advance in manufacturer's tiers, improve word-of-mouth advertising, and increase job satisfaction.

  10. Agency and Achievement: Self-management and Self-regard.

    ERIC Educational Resources Information Center

    Thomas, John W.

    1980-01-01

    Studies in self-management, attribution, and achievement motivation challenge the view that basic skills instruction requires strong teacher control, structure, convergence on learning activities, less pupil freedom, and less experimental teaching activities. Student-managed instruction yielded the greatest achievement gains and heightened…

  11. Effects of digital game-based learning on student engagement and academic achievement

    NASA Astrophysics Data System (ADS)

    Little, Timothy W.

    This experimental study was designed to determine the effect of digital game-based learning on student engagement and academic achievement. The sample was comprised of 34 students enrolled in a secondary Biology class in a rural public school. The study utilized an experimental pretest-posttest design with switching replications. After random assignment, students participated in one of two supplemental learning activities: playing a digital game designed to review science concepts or participating in a lab to review the same concepts. Students subsequently switched activities. Student achievement data were collected on mastery of science concepts, and student engagement data were collected utilizing self- and teacher-reported measures. Data were analyzed using analysis of variance (ANOVA) with repeated measures. Results demonstrated that the digital game was as effective as the lab activity at increasing teacher-reported student engagement and academic achievement. These findings may be of interest to school administrators or directors of teacher preparation programs on the potential effectiveness of digital games as a learning tool.

  12. Can paying for results help to achieve the Millennium Development Goals? Overview of the effectiveness of results-based financing.

    PubMed

    Oxman, Andrew D; Fretheim, Atle

    2009-05-01

    Results-based financing and pay-for-performance refer to the transfer of money or material goods conditional on taking a measurable action or achieving a predetermined performance target. Results-based financing is widely advocated for achieving health goals, including the Millennium Development Goals. We undertook an overview of systematic reviews of the effectiveness of RBF. We searched the Cochrane Library, EMBASE, and MEDLINE (up to August 2007). We also searched for related articles in PubMed, checked the reference lists of retrieved articles, and contacted key informants. We included reviews with a methods section that addressed the effects of any results-based financing in the health sector targeted at patients, providers, organizations, or governments. We summarized the characteristics and findings of each review using a structured format. We found 12 systematic reviews that met our inclusion criteria. Based on the findings of these reviews, financial incentives targeting recipients of health care and individual healthcare professionals are effective in the short run for simple and distinct, well-defined behavioral goals. There is less evidence that financial incentives can sustain long-term changes. Conditional cash transfers to poor and disadvantaged groups in Latin America are effective at increasing the uptake of some preventive services. There is otherwise very limited evidence of the effects of results-based financing in low- or middle-income countries. Results-based financing can have undesirable effects, including motivating unintended behaviors, distortions (ignoring important tasks that are not rewarded with incentives), gaming (improving or cheating on reporting rather than improving performance), widening the resource gap between rich and poor, and dependency on financial incentives. There is limited evidence of the effectiveness of results-based financing and almost no evidence of the cost-effectiveness of results-based financing. Based on the

  13. Experimental Design: Utilizing Microsoft Mathematics in Teaching and Learning Calculus

    ERIC Educational Resources Information Center

    Oktaviyanthi, Rina; Supriani, Yani

    2015-01-01

    The experimental design was conducted to investigate the use of Microsoft Mathematics, free software made by Microsoft Corporation, in teaching and learning Calculus. This paper reports results from experimental study details on implementation of Microsoft Mathematics in Calculus, students' achievement and the effects of the use of Microsoft…

  14. Adsorption of methanol molecule on graphene: Experimental results and first-principles calculations

    NASA Astrophysics Data System (ADS)

    Zhao, X. W.; Tian, Y. L.; Yue, W. W.; Chen, M. N.; Hu, G. C.; Ren, J. F.; Yuan, X. B.

    2018-04-01

    Adsorption properties of methanol molecule on graphene surface are studied both theoretically and experimentally. The adsorption geometrical structures, adsorption energies, band structures, density of states and the effective masses are obtained by means of first-principles calculations. It is found that the electronic characteristics and conductivity of graphene are sensitive to the methanol molecule adsorption. After adsorption of methanol molecule, bandgap appears. With the increasing of the adsorption distance, the bandgap, adsorption energy and effective mass of the adsorption system decreased, hence the resistivity of the system decreases gradually, these results are consistent with the experimental results. All these calculations and experiments indicate that the graphene-based sensors have a wide range of applications in detecting particular molecules.

  15. Theoretical versus experimental results for the rotordynamic coefficients of eccentric, smooth, gas annular seal annular gas seals

    NASA Technical Reports Server (NTRS)

    Childs, Dara W.; Alexander, Chis

    1994-01-01

    This viewgraph presentation presents the following results: (1) The analytical results overpredict the experimental results for the direct stiffness values and incorrectly predict increasing stiffness with decreasing pressure ratios. (2) Theory correctly predicts increasing cross-coupled stiffness, K(sub YX), with increasing eccentricity and inlet preswirl. (3) Direct damping, C(sub XX), underpredicts the experimental results, but the analytical results do correctly show that damping increases with increasing eccentricity. (4) The whirl frequency values predicted by theory are insensitive to changes in the static eccentricity ratio. Although these values match perfectly with the experimental results at 16,000 rpm, the results at the lower speed do not correspond. (5) Theoretical and experimental mass flow rates match at 5000 rpm, but at 16,000 rpm the theoretical results overpredict the experimental mass flow rates. (6) Theory correctly shows the linear pressure profiles and the associated entrance losses with the specified rotor positions.

  16. Achieving ultrahigh vacuum in an unbaked chamber with glow discharge conditioning

    NASA Astrophysics Data System (ADS)

    Khan, Ziauddin; Semwal, Pratibha; Dhanani, Kalpesh R.; Raval, Dilip C.; Pradhan, Subrata

    2017-01-01

    Glow discharge conditioning (GDC) has long been accepted as one of the basic wall conditioning techniques for achieving ultrahigh vacuum in an unbaked chamber. As a part of this fundamental experimental study, a test chamber has been fabricated from stainless steel 304 L with its inner surface electropolished on which a detailed investigation has been carried out. Both helium and hydrogen gases have been employed as discharge cleaning medium. The discharge cleaning was carried out at 0.1 A / m 2 current density with working pressure maintained at 1.0 × 10 -2 mbar. It was experimentally observed that the pump-down time to attain the base pressure 10 -8 mbar was reduced by 62% compared to the unbaked chamber being pumped to this ultimate vacuum. The results were similar irrespective of whether the discharge cleaning medium is either hydrogen or helium. It was also experimentally established that a better ultimate vacuum could be achieved as compared to theoretically calculated ultimate vacuum with the help of discharge cleaning.

  17. Closing the achievement gap through modification of neurocognitive and neuroendocrine function: results from a cluster randomized controlled trial of an innovative approach to the education of children in kindergarten.

    PubMed

    Blair, Clancy; Raver, C Cybele

    2014-01-01

    Effective early education is essential for academic achievement and positive life outcomes, particularly for children in poverty. Advances in neuroscience suggest that a focus on self-regulation in education can enhance children's engagement in learning and establish beneficial academic trajectories in the early elementary grades. Here, we experimentally evaluate an innovative approach to the education of children in kindergarten that embeds support for self-regulation, particularly executive functions, into literacy, mathematics, and science learning activities. Results from a cluster randomized controlled trial involving 29 schools, 79 classrooms, and 759 children indicated positive effects on executive functions, reasoning ability, the control of attention, and levels of salivary cortisol and alpha amylase. Results also demonstrated improvements in reading, vocabulary, and mathematics at the end of kindergarten that increased into the first grade. A number of effects were specific to high-poverty schools, suggesting that a focus on executive functions and associated aspects of self-regulation in early elementary education holds promise for closing the achievement gap.

  18. Closing the Achievement Gap through Modification of Neurocognitive and Neuroendocrine Function: Results from a Cluster Randomized Controlled Trial of an Innovative Approach to the Education of Children in Kindergarten

    PubMed Central

    Blair, Clancy; Raver, C. Cybele

    2014-01-01

    Effective early education is essential for academic achievement and positive life outcomes, particularly for children in poverty. Advances in neuroscience suggest that a focus on self-regulation in education can enhance children’s engagement in learning and establish beneficial academic trajectories in the early elementary grades. Here, we experimentally evaluate an innovative approach to the education of children in kindergarten that embeds support for self-regulation, particularly executive functions, into literacy, mathematics, and science learning activities. Results from a cluster randomized controlled trial involving 29 schools, 79 classrooms, and 759 children indicated positive effects on executive functions, reasoning ability, the control of attention, and levels of salivary cortisol and alpha amylase. Results also demonstrated improvements in reading, vocabulary, and mathematics at the end of kindergarten that increased into the first grade. A number of effects were specific to high-poverty schools, suggesting that a focus on executive functions and associated aspects of self-regulation in early elementary education holds promise for closing the achievement gap. PMID:25389751

  19. Construction of a WMR for trajectory tracking control: experimental results.

    PubMed

    Silva-Ortigoza, R; Márquez-Sánchez, C; Marcelino-Aranda, M; Marciano-Melchor, M; Silva-Ortigoza, G; Bautista-Quintero, R; Ramos-Silvestre, E R; Rivera-Díaz, J C; Muñoz-Carrillo, D

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x₁∗, y₁∗),..., (x(n)∗, y(n)∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software.

  20. Construction of a WMR for Trajectory Tracking Control: Experimental Results

    PubMed Central

    Silva-Ortigoza, R.; Márquez-Sánchez, C.; Marcelino-Aranda, M.; Marciano-Melchor, M.; Silva-Ortigoza, G.; Bautista-Quintero, R.; Ramos-Silvestre, E. R.; Rivera-Díaz, J. C.; Muñoz-Carrillo, D.

    2013-01-01

    This paper reports a solution for trajectory tracking control of a differential drive wheeled mobile robot (WMR) based on a hierarchical approach. The general design and construction of the WMR are described. The hierarchical controller proposed has two components: a high-level control and a low-level control. The high-level control law is based on an input-output linearization scheme for the robot kinematic model, which provides the desired angular velocity profiles that the WMR has to track in order to achieve the desired position (x∗, y∗) and orientation (φ∗). Then, a low-level control law, based on a proportional integral (PI) approach, is designed to control the velocity of the WMR wheels to ensure those tracking features. Regarding the trajectories, this paper provides the solution or the following cases: (1) time-varying parametric trajectories such as straight lines and parabolas and (2) smooth curves fitted by cubic splines which are generated by the desired data points {(x1∗, y1∗),..., (xn∗, yn∗)}. A straightforward algorithm is developed for constructing the cubic splines. Finally, this paper includes an experimental validation of the proposed technique by employing a DS1104 dSPACE electronic board along with MATLAB/Simulink software. PMID:23997679

  1. Pulmonary function in pubertal synchronized swimmers: 1-year follow-up results and its relation to competitive achievement.

    PubMed

    Gabrilo, Goran; Peric, Mia; Stipic, Marija

    2011-03-01

    Pulmonary function (PF) is particularly important in synchronized swimming, considering the characteristics of this sport. However, the sanitizing agents (chlorine) used in pools can have a possible negative influence on the PF parameters. In this study, we observed 24 swimmers (all women, 14 to 16 years of age) and measured their PF and competitive achievement. PF was measured before and after a 1-year period and included standard spirometric variables. Competitive achievement was evidenced during the National Championship. The t-test showed significant increases in body height and weight of the participants and a resulting increase in most of the absolute respiratory flows and pulmonary capacities. Forced vital capacity (FVC) and forced expiratory volume (both in proportion to norm for body height, gender, and age) increased significantly within the study period. FVC significantly predicted the competitive achievement of young swimmers, most probably because artists have to achieve exceptional breath control when upside down underwater. In conclusion, we found no evidence for the eventual negative influence of chlorine and its compounds on the PF of swimmers, and results showed that regular synchronized swim training could improve the PF of young artists.

  2. Sample similarity analysis of angles of repose based on experimental results for DEM calibration

    NASA Astrophysics Data System (ADS)

    Tan, Yuan; Günthner, Willibald A.; Kessler, Stephan; Zhang, Lu

    2017-06-01

    As a fundamental material property, particle-particle friction coefficient is usually calculated based on angle of repose which can be obtained experimentally. In the present study, the bottomless cylinder test was carried out to investigate this friction coefficient of a kind of biomass material, i.e. willow chips. Because of its irregular shape and varying particle size distribution, calculation of the angle becomes less applicable and decisive. In the previous studies only one section of those uneven slopes is chosen in most cases, although standard methods in definition of a representable section are barely found. Hence, we presented an efficient and reliable method from the new technology, 3D scan, which was used to digitize the surface of heaps and generate its point cloud. Then, two tangential lines of any selected section were calculated through the linear least-squares regression (LLSR), such that the left and right angle of repose of a pile could be derived. As the next step, a certain sum of sections were stochastic selected, and calculations were repeated correspondingly in order to achieve sample of angles, which was plotted in Cartesian coordinates as spots diagram. Subsequently, different samples were acquired through various selections of sections. By applying similarities and difference analysis of these samples, the reliability of this proposed method was verified. Phased results provides a realistic criterion to reduce the deviation between experiment and simulation as a result of random selection of a single angle, which will be compared with the simulation results in the future.

  3. Experimental optimization of directed field ionization

    NASA Astrophysics Data System (ADS)

    Liu, Zhimin Cheryl; Gregoric, Vincent C.; Carroll, Thomas J.; Noel, Michael W.

    2017-04-01

    The state distribution of an ensemble of Rydberg atoms is commonly measured using selective field ionization. The resulting time resolved ionization signal from a single energy eigenstate tends to spread out due to the multiple avoided Stark level crossings atoms must traverse on the way to ionization. The shape of the ionization signal can be modified by adding a perturbation field to the main field ramp. Here, we present experimental results of the manipulation of the ionization signal using a genetic algorithm. We address how both the genetic algorithm and the experimental parameters were adjusted to achieve an optimized result. This work was supported by the National Science Foundation under Grants No. 1607335 and No. 1607377.

  4. Does achievement motivation mediate the semantic achievement priming effect?

    PubMed

    Engeser, Stefan; Baumann, Nicola

    2014-10-01

    The aim of our research was to understand the processes of the prime-to-behavior effects with semantic achievement primes. We extended existing models with a perspective from achievement motivation theory and additionally used achievement primes embedded in the running text of excerpts of school textbooks to simulate a more natural priming condition. Specifically, we proposed that achievement primes affect implicit achievement motivation and conducted pilot experiments and 3 main experiments to explore this proposition. We found no reliable positive effect of achievement primes on implicit achievement motivation. In light of these findings, we tested whether explicit (instead of implicit) achievement motivation is affected by achievement primes and found this to be the case. In the final experiment, we found support for the assumption that higher explicit achievement motivation implies that achievement priming affects the outcome expectations. The implications of the results are discussed, and we conclude that primes affect achievement behavior by heightening explicit achievement motivation and outcome expectancies.

  5. At Odds: Reconciling Experimental and Theoretical Results in High School Physics

    ERIC Educational Resources Information Center

    Gates, Joshua

    2009-01-01

    For this experiment, students are divided into 2 groups and presented with a static equilibrium force-balance problem to solve. One group works entirely experimentally and the other group theoretically, using Newton's laws. The groups present their seemingly dissimilar results and must reconcile them through discussion. (Contains 3 figures.)

  6. Goal Setting and Student Achievement: A Longitudinal Study

    ERIC Educational Resources Information Center

    Moeller, Aleidine J.; Theiler, Janine M.; Wu, Chaorong

    2012-01-01

    The connection between goals and student motivation has been widely investigated in the research literature, but the relationship of goal setting and student achievement at the classroom level has remained largely unexplored. This article reports the findings of a 5-year quasi-experimental study examining goal setting and student achievement in…

  7. Problem-Based Learning Environment in Basic Computer Course: Pre-Service Teachers' Achievement and Key Factors for Learning

    ERIC Educational Resources Information Center

    Efendioglu, Akin

    2015-01-01

    This experimental study aims to determine pre-service teachers' achievements and key factors that affect the learning process with regard to problem-based learning (PBL) and lecture-based computer course (LBCC) conditions. The research results showed that the pre-service teachers in the PBL group had significantly higher achievement scores than…

  8. Effects of Adult Learner Participation in Course Planning on Achievement and Satisfaction.

    ERIC Educational Resources Information Center

    Rosenblum, Sandra; Darkenwald, Gordon G.

    1983-01-01

    Hypothesizing that participation in course planning would result in higher achievement and satisfaction, researchers used a posttest-only control group design with continuing education students in two separate experiments. The control group completed the course as planned by the experimental group. No differences were found between the groups in…

  9. Phase transition kinetics in DIET of vanadium pentoxide. I. Experimental results

    NASA Astrophysics Data System (ADS)

    Ai, R.; Fan, H.-J.; Marks, L. D.

    1993-01-01

    Experimental results of the kinetics of phase transformation in vanadium pentoxide during surface loss of oxygen from electron irradiation are described. Phase transformations under three different regimes were examined: (a) low flux; (b) intermediate flux and (c) high flux. Different phase transformation routes were observed under different fluxes. In a companion paper, numerical calculations are presented demonstrating that these results are due to a mixed interface/diffusion controlled phase transition pumped by surface oxygen loss.

  10. Experimental studies of electroweak physics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Etzion, E.

    1997-09-01

    Some experimental new Electroweak physics results measured at the LEP/SLD and the TEVATRON are discussed. The excellent accuracy achieved by the experiments still yield no significant evidence for deviation from the Standard Model predictions, or signal to physics beyond the Standard Model. The Higgs particle still has not been discovered and a low bound is given to its mass.

  11. Behavior of Shape Memory Epoxy Foams in Microgravity: Experimental Results of STS-134 Mission

    NASA Astrophysics Data System (ADS)

    Santo, Loredana; Quadrini, Fabrizio; Squeo, Erica Anna; Dolce, Ferdinando; Mascetti, Gabriele; Bertolotto, Delfina; Villadei, Walter; Ganga, Pier Luigi; Zolesi, Valfredo

    2012-09-01

    Shape memory epoxy foams were used for an experiment on the International Space Station to evaluate the feasibility of their use for building multi-functional composite structures. A small equipment was designed and built to simulate the actuation of simple devices in micro-gravity conditions: three different configurations (compression, bending and torsion) were chosen during the memory step of the foams so as to produce their recovery on ISS. Two systems were used for the experimentation to avoid damages of the flight model during laboratory tests; however a single ground experiment was performed also on the flight model before the mission. Micro-gravity does not affect the ability of the foams to recover their shape but it poses strong limits for the heating system design because of the difference in heat transfer on earth and in orbit. A full recovery of the foam samples was not achieved due to some limitations in the maximum allowable temperature on ISS for safety reasons: anyway a 70% recovery was also measured at a temperature of 110°C. Ground laboratory experiments showed that 100% recovery could be reached by increasing the maximum temperature to 120°C. Experiment results have provided many useful information for the designing of a new structural composite actuator by using shape memory foams.

  12. The Effects of Cooperative and Individualistic Learning Structures on Achievement in a College-Level Computer-Aided Drafting Course

    ERIC Educational Resources Information Center

    Swab, A. Geoffrey

    2012-01-01

    This study of cooperative learning in post-secondary engineering education investigated achievement of engineering students enrolled in two intact sections of a computer-aided drafting (CAD) course. Quasi-experimental and qualitative methods were employed in comparing student achievement resulting from out-of-class cooperative and individualistic…

  13. Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA)

    NASA Astrophysics Data System (ADS)

    Bates, E. M.; Birmingham, W. J.; Romero-Talamás, C. A.

    2018-05-01

    The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.

  14. Design and experimental results of the 1-T Bitter Electromagnet Testing Apparatus (BETA).

    PubMed

    Bates, E M; Birmingham, W J; Romero-Talamás, C A

    2018-05-01

    The Bitter Electromagnet Testing Apparatus (BETA) is a 1-Tesla (T) technical prototype of the 10 T Adjustable Long Pulsed High-Field Apparatus. BETA's final design specifications are highlighted in this paper which include electromagnetic, thermal, and stress analyses. We discuss here the design and fabrication of BETA's core, vessel, cooling, and electrical subsystems. The electrical system of BETA is composed of a scalable solid-state DC breaker circuit. Experimental results display the stable operation of BETA at 1 T. These results are compared to both analytical design and finite element calculations. Experimental results validate analytical magnet designing methods developed at the Dusty Plasma Laboratory. The theoretical steady state maxima and the limits of BETA's design are explored in this paper.

  15. Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results.

    PubMed

    Humada, Ali M; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M; Ahmed, Mushtaq N

    2016-01-01

    A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions.

  16. Experimental Results from a Resonant Dielectric Laser Accelerator

    NASA Astrophysics Data System (ADS)

    Yoder, Rodney; McNeur, Joshua; Sozer, Esin; Travish, Gil; Hazra, Kiran Shankar; Matthews, Brian; England, Joel; Peralta, Edgar; Wu, Ziran

    2015-04-01

    Laser-powered accelerators have the potential to operate with very large accelerating gradients (~ GV/m) and represent a path toward extremely compact colliders and accelerator technology. Optical-scale laser-powered devices based on field-shaping structures (known as dielectric laser accelerators, or DLAs) have been described and demonstrated recently. Here we report on the first experimental results from the Micro-Accelerator Platform (MAP), a DLA based on a slab-symmetric resonant optical-scale structure. As a resonant (rather than near-field) device, the MAP is distinct from other DLAs. Its cavity resonance enhances its accelerating field relative to the incoming laser fields, which are coupled efficiently through a diffractive optic on the upper face of the device. The MAP demonstrated modest accelerating gradients in recent experiments, in which it was powered by a Ti:Sapphire laser well below its breakdown limit. More detailed results and some implications for future developments will be discussed. Supported in part by the U.S. Defense Threat Reduction Agency (UCLA); U.S. Dept of Energy (SLAC); and DARPA (SLAC).

  17. From Deuterium to Free Neutrons - Recent Experimental Results

    NASA Astrophysics Data System (ADS)

    Kuhn, Sebastian

    2009-05-01

    Lepton scattering has long been used to gather data on the internal structure of both protons and neutrons. Assuming isospin symmetry, these data can be used to pin down the contributions of both u and d quarks to the spatial and momentum-spin structure of the nucleon and its excitations. In this context, information on the neutron is crucial and is typically obtained from experiments on few-body nuclear targets (predominantly ^3He and deuterium). However, the need to account for binding effects complicates the interpretation of these experiments. On the other hand, detailed studies of the reaction mechanism can yield important new information on the structure of few-body nuclei and the interplay of nuclear and quark degrees of freedom. Recent theoretical and experimental advances have allowed us to make significant progress on both fronts -- a cleaner extraction of neutron properties from nuclear data and a better understanding of nuclear modifications of the bound neutron structure. I will concentrate on recent results on the deuteron. I will present a new extraction of neutron spin structure functions in the resonance and large-x region (from the EG1 experiment with CLAS at Jefferson Lab). The same data can also be used for a detailed comparison with modern calculations of quasi-elastic spin-dependent scattering on the deuteron. A second experimental program with CLAS uses the technique of ``spectator tagging'' to extract the unpolarized structure functions of the neutron with minimal uncertainties from nuclear effects. By mapping out the dependence of the cross section on the ``spectator'' momentum, we can learn about final state interactions between the struck nucleon and the spectator, as well as modifications of the neutron structure due to nuclear binding. I will present preliminary results from the ``BoNuS'' experiment which pushed the detection limit of the spectator proton down to momenta of 70 MeV/c, where nuclear corrections should become small.

  18. Promoting walking to school: results of a quasi‐experimental trial

    PubMed Central

    McKee, Rosie; Mutrie, Nanette; Crawford, Fiona; Green, Brian

    2007-01-01

    Study objective To assess the impact of a combined intervention on children's travel behaviour, stage of behavioural change and motivations for and barriers to actively commuting to school. Design A quasi‐experimental trial involving pre‐ and post‐intervention mapping of routes to school by active and inactive mode of travel and surveys of “stage of behaviour change” and motivations for and barriers to actively commuting to school. Intervention The intervention school participated in a school‐based active travel project for one school term. Active travel was integrated into the curriculum and participants used interactive travel‐planning resources at home. The control school participated in before and after measurements but did not receive the intervention. Setting Two primary schools in Scotland with similar socioeconomic and demographic profiles. Participants Two classes of primary 5 children and their families and teachers. Main results Post intervention, the mean distance travelled to school by walking by intervention children increased significantly from baseline, from 198 to 772 m (389% increase). In the control group mean distance walked increased from 242 to 285 m (17% increase). The difference between the schools was significant (t (38)  = −4.679, p<0.001 (95% confidence interval −315 to −795 m)). Post intervention, the mean distance travelled to school by car by intervention children reduced significantly from baseline, from 2018 to 933 m (57.5% reduction). The mean distance travelled to school by car by control children increased from baseline, from 933 to 947 m (1.5% increase). The difference in the change between schools was significant (t (32)  = 4.282, p<0.001 (95% confidence interval 445 to 1255 m)). Conclusions Intervention was effective in achieving an increase in the mean distance travelled by active mode and a reduction in the mean distance travelled by inactive mode on school journey. PMID:17699538

  19. Physical mechanism of comet outbursts - An experimental result

    NASA Technical Reports Server (NTRS)

    Hartmann, William K.

    1993-01-01

    Attention is given to an experimental investigation of the physical mechanism of comet outbursts which is consistent with the general picture of mantle presence on comets and clarifies the relation of mantles to eruptive activity. The experiment and closeup observation of Comet P/Halley suggest a result different from most mathematical models in that the release of gas pressure does not occur only from uniform gas flow out of the entire surface. In some active comets near perihelion within a few AU of the sun, gas production rates and disturbance of the surface may be so high that the outflow is nearly continuous, with the regolith being entirely stripped away, as in many of the models. The present model provides a cyclic eruption and recharge mechanism which is lacking in most other models.

  20. Improving preschoolers' mathematics achievement with tablets: a randomized controlled trial

    NASA Astrophysics Data System (ADS)

    Schacter, John; Jo, Booil

    2017-09-01

    With a randomized field experiment of 433 preschoolers, we tested a tablet mathematics program designed to increase young children's mathematics learning. Intervention students played Math Shelf, a comprehensive iPad preschool and year 1 mathematics app, while comparison children received research-based hands-on mathematics instruction delivered by their classroom teachers. After 22 weeks, there was a large and statistically significant effect on mathematics achievement for Math Shelf students (Cohen's d = .94). Moderator analyses demonstrated an even larger effect for low achieving children (Cohen's d = 1.27). These results suggest that early education teachers can improve their students' mathematics outcomes by integrating experimentally proven tablet software into their daily routines.

  1. Wind Code Application to External Forebody Flowfields with Comparisons to Experimental Results

    NASA Technical Reports Server (NTRS)

    Frate, F. C.; Kim, H. D.

    2001-01-01

    The WIND Code, a general purpose Navier-Stokes solver, has been utilized to obtain supersonic external flowfield Computational Fluid Dynamics (CFD) solutions over an axisymmetric, parabolic forebody with comparisons made to wind tunnel experimental results. Various cases have been investigated at supersonic freestream conditions ranging from Mach 2.0 to 3.5, at 0 deg and 3 deg angles-of-attack, and with either a sharp-nose or blunt-nose forebody configuration. Both a turbulent (Baldwin-Lomax algebraic turbulence model) and a laminar model have been implemented in the CFD. Obtaining the solutions involved utilizing either the parabolized- or full-Navier-Stokes analyses supplied in WIND. Comparisons have been made with static pressure measurements, with boundary-layer rake and flowfield rake pitot pressure measurements, and with temperature sensitive paint experimental results. Using WIND's parabolized Navier-Stokes capability, grid sequencing, and the Baldwin-Lomax algebraic turbulence model allowed for significant reductions in computational time while still providing good agreement with experiment. Given that CFD and experiment compare well, WIND is found to be a good computational platform for solving this type of forebody problem, and the grids developed in conjunction with it will be used in the future to investigate varying freestream conditions not tested experimentally.

  2. Effective Teaching Results in Increased Science Achievement for All Students

    ERIC Educational Resources Information Center

    Johnson, Carla C.; Kahle, Jane Butler; Fargo, Jamison D.

    2007-01-01

    This study of teacher effectiveness and student achievement in science demonstrated that effective teachers positively impact student learning. A general linear mixed model was used to assess change in student scores on the Discovery Inquiry Test as a function of time, race, teacher effectiveness, gender, and impact of teacher effectiveness in…

  3. The District-Wide Effectiveness of the Achieve3000 Program: A Quasi-Experimental Study

    ERIC Educational Resources Information Center

    Borman, Geoffrey D.; Park, So Jung; Min, Sookweon

    2015-01-01

    The purpose of this study was to evaluate the impact of Achieve3000, a differentiated online literacy curriculum, on students' scores on the California State Test (CST). In the 2011-12 school year, 1,957 students in Chula Vista began using Achieve3000's solutions in 3rd through 8th grade. Using a form of propensity score matching called Inverse…

  4. Photovoltaic Grid-Connected Modeling and Characterization Based on Experimental Results

    PubMed Central

    Humada, Ali M.; Hojabri, Mojgan; Sulaiman, Mohd Herwan Bin; Hamada, Hussein M.; Ahmed, Mushtaq N.

    2016-01-01

    A grid-connected photovoltaic (PV) system operates under fluctuated weather condition has been modeled and characterized based on specific test bed. A mathematical model of a small-scale PV system has been developed mainly for residential usage, and the potential results have been simulated. The proposed PV model based on three PV parameters, which are the photocurrent, IL, the reverse diode saturation current, Io, the ideality factor of diode, n. Accuracy of the proposed model and its parameters evaluated based on different benchmarks. The results showed that the proposed model fitting the experimental results with high accuracy compare to the other models, as well as the I-V characteristic curve. The results of this study can be considered valuable in terms of the installation of a grid-connected PV system in fluctuated climatic conditions. PMID:27035575

  5. The Effects of Concealing Academic Achievement Information on Adolescents' Self-Concept

    ERIC Educational Resources Information Center

    Zhang, Baoshan; Wang, Mo; Li, Juan; Yu, Guoliang; Bi, Yan-Ling

    2011-01-01

    Using an experimental design, the effect of concealing academic achievement information on adolescents' self-concept was examined in the current study. Specifically, adolescents with low academic achievement and adolescents with average to high academic achievement (N = 129) were randomly assigned to different interview contexts wherein…

  6. Self-reflection, gender and science achievement

    NASA Astrophysics Data System (ADS)

    Shoop, Kathleen A.

    Drawing on socio-cognitive learning theory, this study compared achievement scores of 134 male and female high school biology students randomly assigned to groups which either used self-reflection, used self-reflection and received feedback, or did not self-reflect. Following a pretest, the teacher provided self-reflection strategy instruction to students in the two intervention groups and then subsequently provided in-class self-reflection time for these groups. The posttest concluded the unit; the retention measure was five weeks later. A quasi-experimental 3 x 3 x 2 (time x intervention x gender) factorial repeated-measures control group design was used for this study; a repeated measures ANOVA and several one-way ANOVA's were used to answer the research questions. Results from the repeated-measures ANOVA revealed significant results for Time and Time x Intervention, with the reflection group demonstrating significantly lower gains from pretest to posttest than the other two groups. The ANOVA examining differences between those who reflected and those who reflected and received feedback provided significant results with similar results for the difference between the control group and the reflection group. For teachers and students this study provides several areas of practical significance. Primarily, teachers may find lower student achievement if students regularly self-reflect but do not receive feedback for their reflection.

  7. Experimental results for characterization of a tapered plastic optical fiber sensor based on SPR

    NASA Astrophysics Data System (ADS)

    Cennamo, N.; Galatus, R.; Zeni, L.

    2015-05-01

    The experimental results obtained with two different Plastic Optical Fiber (POF) geometries, tapered and not-tapered, for a sensor based on Surface Plasmon Resonance (SPR) are presented. SPR is used for determining the refractive index variations at the interface between a gold layer and a dielectric medium (aqueous medium). In this work SPR sensors in POF configurations, useful for bio-sensing applications, have been realized for the optimization of the sensitivity and experimentally tested. The results show as the sensitivity increases with the tapered POF configuration, when the refractive index of aqueous medium increases.

  8. Experimental features of natural thermally assisted OSL (NTA-OSL) signal in various quartz samples; preliminary results

    NASA Astrophysics Data System (ADS)

    Polymeris, George S.; Şahiner, Eren; Meriç, Niyazi; Kitis, George

    2015-04-01

    The access to the OSL signals from very deep traps is achieved by an alternative experimental method which comprises combined action of thermal and optical stimulation, termed as thermally assisted OSL (TA-OSL). This experimental technique was suggested in order to not only measure the signal of the deep traps without heating the sample to temperatures greater than 500 °C, but also use the former for dosimetry purposes as well, due to exhibiting a number of interesting properties which could be effectively used towards dosimetry purposes, especially for large accumulated artificial doses. The present study provides for the first time in the literature with preliminary results towards the feasibility study of the naturally occurring TA-OSL signal in coarse grains of natural quartz towards its effective application to geological dating. The samples subjected to the present study were collected from fault lines in Kütahya-Simav, Western Anatolia Region, Turkey; independent luminescence approaches yielded an equivalent dose larger than 100 Gy. Several experimental luminescence features were studied, such as sensitivity, reproducibility, TA-OSL curve shape as well as the correlation between NTA-OSL and NTL/NOSL. Nevertheless, special emphasis was addressed towards optimizing the measuring conditions of the TA-OSL signal. The high intensity of the OSL signal confirms the existence of a transfer phenomenon from deep electron traps. The increase of the integrated TA-OSL signal as a function of temperature is monitored for temperatures up to 180 °C, indicating the later as the most effective stimulation temperature. At all temperatures of the studied temperature range between 75 and 260 °C, the shape of the signal resembles much the shape of a typical CW-OSL curve. However, a long-lived, residual NTA-OSL component was monitored after the primary, initial NTA-OSL measured at 180 °C; the intensity of this component increases with increasing stimulation temperature. The

  9. School Personnel-Student Racial Congruence and the Achievement Gap

    ERIC Educational Resources Information Center

    Moore, Allison B.; MacGregor, Cynthia; Cornelius-White, Jeffrey

    2017-01-01

    Purpose: This paper aims to examine the relationship between student achievement and racial congruence of school personnel and students to help educators and policy makers narrow the achievement gap. Design/methodology/approach: This quasi-experimental, correlational study used publicly available data from 158 elementary schools in the Houston…

  10. Propagation effects for land mobile satellite systems: Overview of experimental and modeling results

    NASA Technical Reports Server (NTRS)

    Goldhirsh, Julius; Vogel, Wolfhard J.

    1992-01-01

    Models developed and experiments performed to characterize the propagation environment associated with land mobile communication using satellites are discussed. Experiments were carried out with transmitters on stratospheric balloons, remotely piloted aircraft, helicopters, and geostationary satellites. This text is comprised of compiled experimental results for the expressed use of communications engineers, designers of planned Land Mobile Satellite Systems (LMSS), and modelers of propagation effects. The results presented here are mostly derived from systematic studies of propagation effects for LMSS geometries in the United States associated with rural and suburban regions. Where applicable, the authors also draw liberally from the results of other related investigations in Canada, Europe, and Australia. Frequencies near 1500 MHz are emphasized to coincide with frequency bands allocated for LMSS by the International Telecommunication Union, although earlier experimental work at 870 MHz is also included.

  11. Experimental Results for Titan Aerobot Thermo-Mechanical Subsystem Development

    NASA Technical Reports Server (NTRS)

    Hall, Jeffrey L.; Jones, J. A.; Kerzhanovich, V. V.; Lachenmeier, T.; Mahr, P.; Pauken, M.; Plett, G. A.; Smith, L.; VanLuvender, M. L.; Yavrouian, A. H.

    2006-01-01

    This paper describes experimental results from a development program focused in maturing Titan aerobot technology in the areas of mechanical and thermal subsystems. Results from four key activities are described: first, a cryogenic balloon materials development program involving coupon and cylinder tests and culminating in the fabrication and testing of an inflated 4.6 m long prototype blimp at 93 K; second, a combined lab experiment and numerical simulation effort to assess potential problems resulting from radioisotope thermal generator waste heat generation near an inflated blimp; third, an aerial deployment and inflation development program consisting of laboratory and helicopter drop tests on a near full scale (11 m long) prototype blimp; and fourth, a proof of concept experiment demonstrating the viability of using a mechanically steerable high gain antenna on a floating blimp to perform direct to Earth telecommunications from Titan. The paper provides details on all of these successful activities and discusses their impact on the overall effort to produce mature systems technology for future Titan aerobot missions.

  12. Computer Assisted Project-Based Instruction: The Effects on Science Achievement, Computer Achievement and Portfolio Assessment

    ERIC Educational Resources Information Center

    Erdogan, Yavuz; Dede, Dinçer

    2015-01-01

    The purpose of this study is to compare the effects of computer assisted project-based instruction on learners' achievement in a science and technology course, in a computer course and in portfolio development. With this aim in mind, a quasi-experimental design was used and a sample of 70 seventh grade secondary school students from Org. Esref…

  13. Results of an Experimental Exploration of Advanced Automated Geospatial Tools: Agility in Complex Planning

    DTIC Science & Technology

    2009-06-01

    AUTOMATED GEOSPATIAL TOOLS : AGILITY IN COMPLEX PLANNING Primary Topic: Track 5 – Experimentation and Analysis Walter A. Powell [STUDENT] - GMU...TITLE AND SUBTITLE Results of an Experimental Exploration of Advanced Automated Geospatial Tools : Agility in Complex Planning 5a. CONTRACT NUMBER...Std Z39-18 Abstract Typically, the development of tools and systems for the military is requirement driven; systems are developed to meet

  14. Hydrolysis of aluminum dross material to achieve zero hazardous waste.

    PubMed

    David, E; Kopac, J

    2012-03-30

    A simple method with high efficiency for generating high pure hydrogen by hydrolysis in tap water of highly activated aluminum dross is established. Aluminum dross is activated by mechanically milling to particles of about 45 μm. This leads to removal of surface layer of the aluminum particles and creation of a fresh chemically active metal surface. In contact with water the hydrolysis reaction takes place and hydrogen is released. In this process a Zero Waste concept is achieved because the other product of reaction is aluminum oxide hydroxide (AlOOH), which is nature-friendly and can be used to make high quality refractory or calcium aluminate cement. For comparison we also used pure aluminum powder and alkaline tap water solution (NaOH, KOH) at a ratio similar to that of aluminum dross content. The rates of hydrogen generated in hydrolysis reaction of pure aluminum and aluminum dross have been found to be similar. As a result of the experimental setup, a hydrogen generator was designed and assembled. Hydrogen volume generated by hydrolysis reaction was measured. The experimental results obtained reveal that aluminum dross could be economically recycled by hydrolysis process with achieving zero hazardous aluminum dross waste and hydrogen generation. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Preliminary experimental results from a MARS Micro-CT system.

    PubMed

    He, Peng; Yu, Hengyong; Thayer, Patrick; Jin, Xin; Xu, Qiong; Bennett, James; Tappenden, Rachael; Wei, Biao; Goldstein, Aaron; Renaud, Peter; Butler, Anthony; Butler, Phillip; Wang, Ge

    2012-01-01

    The Medipix All Resolution System (MARS) system is a commercial spectral/multi-energy micro-CT scanner designed and assembled by the MARS Bioimaging, Ltd. in New Zealand. This system utilizes the state-of-the-art Medipix photon-counting, energy-discriminating detector technology developed by a collaboration at European Organization for Nuclear Research (CERN). In this paper, we report our preliminary experimental results using this system, including geometrical alignment, photon energy characterization, protocol optimization, and spectral image reconstruction. We produced our scan datasets with a multi-material phantom, and then applied ordered subset-simultaneous algebraic reconstruction technique (OS-SART) to reconstruct images in different energy ranges and principal component analysis (PCA) to evaluate spectral deviation among the energy ranges.

  16. Shuttle Return To Flight Experimental Results: Cavity Effects on Boundary Layer Transition

    NASA Technical Reports Server (NTRS)

    Liechty, Derek S.; Horvath, Thomas J.; Berry, Scott A.

    2006-01-01

    The effect of an isolated rectangular cavity on hypersonic boundary layer transition of the windward surface of the Shuttle Orbiter has been experimentally examined in the Langley Aerothermodynamics Laboratory in support of an agency-wide effort to prepare the Shuttle Orbiter for return to flight. This experimental study was initiated to provide a cavity effects database for developing hypersonic transition criteria to support on-orbit decisions to repair a damaged thermal protection system. Boundary layer transition results were obtained using 0.0075-scale Orbiter models with simulated tile damage (rectangular cavities) of varying length, width, and depth. The database contained within this report will be used to formulate cavity-induced transition correlations using predicted boundary layer edge parameters.

  17. Internal wave emission from baroclinic jets: experimental results

    NASA Astrophysics Data System (ADS)

    Borcia, Ion D.; Rodda, Costanza; Harlander, Uwe

    2016-04-01

    Large-scale balanced flows can spontaneously radiate meso-scale inertia-gravity waves (IGWs) and are thus in fact unbalanced. While flow-dependent parameterizations for the radiation of IGWs from orographic and convective sources do exist, the situation is less developed for spontaneously emitted IGWs. Observations identify increased IGW activity in the vicinity of jet exit regions. A direct interpretation of those based on geostrophic adjustment might be tempting. However, directly applying this concept to the parameterization of spontaneous imbalance is difficult since the dynamics itself is continuously re-establishing an unbalanced flow which then sheds imbalances by GW radiation. Examining spontaneous IGW emission in the atmosphere and validating parameterization schemes confronts the scientist with particular challenges. Due to its extreme complexity, GW emission will always be embedded in the interaction of a multitude of interdependent processes, many of which are hardly detectable from analysis or campaign data. The benefits of repeated and more detailed measurements, while representing the only source of information about the real atmosphere, are limited by the non-repeatability of an atmospheric situation. The same event never occurs twice. This argues for complementary laboratory experiments, which can provide a more focused dialogue between experiment and theory. Indeed, life cycles are also examined in rotating-annulus laboratory experiments. Thus, these experiments might form a useful empirical benchmark for theoretical and modeling work that is also independent of any sort of subgrid model. In addition, the more direct correspondence between experimental and model data and the data reproducibility makes lab experiments a powerful testbed for parameterizations. Here we show first results from a small rotating annulus experiments and we will further present our new experimental facility to study wave emission from jets and fronts.

  18. Application of an Unstructured Grid Navier-Stokes Solver to a Generic Helicopter Boby: Comparison of Unstructured Grid Results with Structured Grid Results and Experimental Results

    NASA Technical Reports Server (NTRS)

    Mineck, Raymond E.

    1999-01-01

    An unstructured-grid Navier-Stokes solver was used to predict the surface pressure distribution, the off-body flow field, the surface flow pattern, and integrated lift and drag coefficients on the ROBIN configuration (a generic helicopter) without a rotor at four angles of attack. The results are compared to those predicted by two structured- grid Navier-Stokes solvers and to experimental surface pressure distributions. The surface pressure distributions from the unstructured-grid Navier-Stokes solver are in good agreement with the results from the structured-grid Navier-Stokes solvers. Agreement with the experimental pressure coefficients is good over the forward portion of the body. However, agreement is poor on the lower portion of the mid-section of the body. Comparison of the predicted surface flow patterns showed similar regions of separated flow. Predicted lift and drag coefficients were in fair agreement with each other.

  19. Computer simulations in the high school: students' cognitive stages, science process skills and academic achievement in microbiology

    NASA Astrophysics Data System (ADS)

    Huppert, J.; Michal Lomask, S.; Lazarowitz, R.

    2002-08-01

    Computer-assisted learning, including simulated experiments, has great potential to address the problem solving process which is a complex activity. It requires a highly structured approach in order to understand the use of simulations as an instructional device. This study is based on a computer simulation program, 'The Growth Curve of Microorganisms', which required tenth grade biology students to use problem solving skills whilst simultaneously manipulating three independent variables in one simulated experiment. The aims were to investigate the computer simulation's impact on students' academic achievement and on their mastery of science process skills in relation to their cognitive stages. The results indicate that the concrete and transition operational students in the experimental group achieved significantly higher academic achievement than their counterparts in the control group. The higher the cognitive operational stage, the higher students' achievement was, except in the control group where students in the concrete and transition operational stages did not differ. Girls achieved equally with the boys in the experimental group. Students' academic achievement may indicate the potential impact a computer simulation program can have, enabling students with low reasoning abilities to cope successfully with learning concepts and principles in science which require high cognitive skills.

  20. Robotic follower experimentation results: ready for FCS increment I

    NASA Astrophysics Data System (ADS)

    Jaczkowski, Jeffrey J.

    2003-09-01

    Robotics is a fundamental enabling technology required to meet the U.S. Army's vision to be a strategically responsive force capable of domination across the entire spectrum of conflict. The U. S. Army Research, Development and Engineering Command (RDECOM) Tank Automotive Research, Development & Engineering Center (TARDEC), in partnership with the U.S. Army Research Laboratory, is developing a leader-follower capability for Future Combat Systems. The Robotic Follower Advanced Technology Demonstration (ATD) utilizes a manned leader to provide a highlevel proofing of the follower's path, which operates with minimal user intervention. This paper will give a programmatic overview and discuss both the technical approach and operational experimentation results obtained during testing conducted at Ft. Bliss, New Mexico in February-March 2003.

  1. Epistemology and expectations survey about experimental physics: Development and initial results

    NASA Astrophysics Data System (ADS)

    Zwickl, Benjamin M.; Hirokawa, Takako; Finkelstein, Noah; Lewandowski, H. J.

    2014-06-01

    In response to national calls to better align physics laboratory courses with the way physicists engage in research, we have developed an epistemology and expectations survey to assess how students perceive the nature of physics experiments in the contexts of laboratory courses and the professional research laboratory. The Colorado Learning Attitudes about Science Survey for Experimental Physics (E-CLASS) evaluates students' epistemology at the beginning and end of a semester. Students respond to paired questions about how they personally perceive doing experiments in laboratory courses and how they perceive an experimental physicist might respond regarding their research. Also, at the end of the semester, the E-CLASS assesses a third dimension of laboratory instruction, students' reflections on their course's expectations for earning a good grade. By basing survey statements on widely embraced learning goals and common critiques of teaching labs, the E-CLASS serves as an assessment tool for lab courses across the undergraduate curriculum and as a tool for physics education research. We present the development, evidence of validation, and initial formative assessment results from a sample that includes 45 classes at 20 institutions. We also discuss feedback from instructors and reflect on the challenges of large-scale online administration and distribution of results.

  2. Tilted wheel satellite attitude control with air-bearing table experimental results

    NASA Astrophysics Data System (ADS)

    Inumoh, Lawrence O.; Forshaw, Jason L.; Horri, Nadjim M.

    2015-12-01

    Gyroscopic actuators for satellite control have attracted significant research interest over the years, but their viability for the control of small satellites has only recently started to become clear. Research on variable speed gyroscopic actuators has long been focused on single gimbal actuators; double gimbal actuators typically operate at constant wheel spin rate and allow tilt angle ranges far larger than the ranges needed to operate most satellite missions. This research examines a tilted wheel, a newly proposed type of inertial actuator that can generate torques in all three principal axes of a rigid satellite using a spinning wheel and a double tilt mechanism. The tilt mechanism tilts the angular momentum vector about two axes providing two degree of freedom control, while variation of the wheel speed provides the third. The equations of motion of the system lead to a singularity-free system during nominal operation avoiding the need for complex steering logic. This paper describes the hardware design of the tilted wheel and the experimental setup behind both standalone and spherical air-bearing tables used to test it. Experimental results from the air bearing table are provided with the results depicting the high performance capabilities of the proposed actuator in torque generation.

  3. Circular Samples as Objects for Magnetic Resonance Imaging - Mathematical Simulation, Experimental Results

    NASA Astrophysics Data System (ADS)

    Frollo, Ivan; Krafčík, Andrej; Andris, Peter; Přibil, Jiří; Dermek, Tomáš

    2015-12-01

    Circular samples are the frequent objects of "in-vitro" investigation using imaging method based on magnetic resonance principles. The goal of our investigation is imaging of thin planar layers without using the slide selection procedure, thus only 2D imaging or imaging of selected layers of samples in circular vessels, eppendorf tubes,.. compulsorily using procedure "slide selection". In spite of that the standard imaging methods was used, some specificity arise when mathematical modeling of these procedure is introduced. In the paper several mathematical models were presented that were compared with real experimental results. Circular magnetic samples were placed into the homogenous magnetic field of a low field imager based on nuclear magnetic resonance. For experimental verification an MRI 0.178 Tesla ESAOTE Opera imager was used.

  4. Summary of experimental heat-transfer results from the turbine hot section facility

    NASA Technical Reports Server (NTRS)

    Gladden, Herbert J.; Yeh, Fredrick C.

    1993-01-01

    Experimental data from the turbine Hot Section Facility are presented and discussed. These data include full-coverage film-cooled airfoil results as well as special instrumentation results obtained at simulated real engine conditions. Local measurements of airfoil wall temperature, airfoil gas-path static-pressure distribution, and local heat-transfer coefficient distributions are presented and discussed. In addition, measured gas and coolant temperatures and pressures are presented. These data are also compared with analyses from Euler and boundary-layer codes.

  5. Stimulating Contributions to Public Goods through Information Feedback: Some Experimental Results

    PubMed Central

    Janssen, Marco A.; Lee, Allen; Sundaram, Hari

    2016-01-01

    In traditional public good experiments participants receive an endowment from the experimenter that can be invested in a public good or kept in a private account. In this paper we present an experimental environment where participants can invest time during five days to contribute to a public good. Participants can make contributions to a linear public good by logging into a web application and performing virtual actions. We compared four treatments, with different group sizes and information of (relative) performance of other groups. We find that information feedback about performance of other groups has a small positive effect if we control for various attributes of the groups. Moreover, we find a significant effect of the contributions of others in the group in the previous day on the number of points earned in the current day. Our results confirm that people participate more when participants in their group participate more, and are influenced by information about the relative performance of other groups. PMID:27459070

  6. National Ignition Facility: Experimental plan

    NASA Astrophysics Data System (ADS)

    1994-05-01

    As part of the Conceptual Design Report (CDR) for the National Ignition Facility (NIF), scientists from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Sandia National Laboratory (SNL), the University of Rochester's Laboratory for Laser Energetics (UR/LLE), and EG&G formed an NIF Target Diagnostics Working Group. The purpose of the Target Diagnostics Working Group is to prepare conceptual designs of target diagnostics for inclusion in the facility CDR and to determine how these specifications impact the CDR. To accomplish this, a subgroup has directed its efforts at constructing an approximate experimental plan for the ignition campaign of the NIF CDR. The results of this effort are contained in this document, the Experimental Plan for achieving fusion ignition in the NIF. This group initially concentrated on the flow-down requirements of the experimental campaign leading to ignition, which will dominate the initial efforts of the NIF. It is envisaged, however, that before ignition, there will be parallel campaigns supporting weapons physics, weapons effects, and other research. This plan was developed by analyzing the sequence of activities required to finally fire the laser at the level of power and precision necessary to achieve the conditions of an ignition hohlraum target, and to then use our experience in activating and running Nova experiments to estimate the rate of completing these activities.

  7. The effect of A teacher questioning strategy training program on teaching behavior, student achievement, and retention

    NASA Astrophysics Data System (ADS)

    Otto, Paul B.; Schuck, Robert F.

    The use of questions in the classroom has been employed throughout the recorded history of teaching. One still hears the term Socratic method during discussions of questioning procedures. The use of teacher questions is presently viewed as a viable procedure for effective instruction. This study was conducted to investigate the feasibility of training teachers in the use of a questioning technique and the resultant effect upon student learning. The Post-Test Only Control Group Design was used in randomly assigning teachers and students to experimental and control groups. A group of teachers was trained in the use of a specific questioning technique. Follow-up periodic observations were made of questioning technique behavior while teaching science units to groups of students. Post-unit achievement tests were administered to the student groups to obtain evidence of a relationship between the implementation of specific types of teacher questions and student achievement and retention. Analysis of observation data indicated a higher use of managerial and rhetorical questions by the control group than the experimental group. The experimental group employed a greater number of recall and data gathering questions as well as higher order data processing and data verification type questions. The student posttest achievement scores for both units of instruction were greater for the experimental groups than for the control groups. The retention scores for both units were Beater for the experimental groups than for the control groups.

  8. Experimental Validation of a Thermoelastic Model for SMA Hybrid Composites

    NASA Technical Reports Server (NTRS)

    Turner, Travis L.

    2001-01-01

    This study presents results from experimental validation of a recently developed model for predicting the thermomechanical behavior of shape memory alloy hybrid composite (SMAHC) structures, composite structures with an embedded SMA constituent. The model captures the material nonlinearity of the material system with temperature and is capable of modeling constrained, restrained, or free recovery behavior from experimental measurement of fundamental engineering properties. A brief description of the model and analysis procedures is given, followed by an overview of a parallel effort to fabricate and characterize the material system of SMAHC specimens. Static and dynamic experimental configurations for the SMAHC specimens are described and experimental results for thermal post-buckling and random response are presented. Excellent agreement is achieved between the measured and predicted results, fully validating the theoretical model for constrained recovery behavior of SMAHC structures.

  9. City Connects: Building an Argument for Effects on Student Achievement with a Quasi-Experimental Design

    ERIC Educational Resources Information Center

    Walsh, Mary; Raczek, Anastasia; Sibley, Erin; Lee-St. John, Terrence; An, Chen; Akbayin, Bercem; Dearing, Eric; Foley, Claire

    2015-01-01

    While randomized experimental designs are the gold standard in education research concerned with causal inference, non-experimental designs are ubiquitous. For researchers who work with non-experimental data and are no less concerned for causal inference, the major problem is potential omitted variable bias. In this presentation, the authors…

  10. Design and Experimental Results for the S406 Airfoil

    DTIC Science & Technology

    2010-08-01

    Concluded.45 46 (a) R = 0.50 × 106. Figure 14.- Comparison of theoretical and experimental section ch with transition free.aracteristics 47 (b) R...106. Figure 15.- Comparison of theoretical and experimental section ch with transition fixed.aracteristics 51 (b) R = 0.70 × 106. Figure 15...04986 4.088 .7022 .013251 −.04644 5.104 . 7845 .014147 −.04381 6.119 .8571 .015149 −.04019 7.135 .9294 .016691 −.03508 8.149 .9947 .017447 −.03106 9.162

  11. High-risk population health management--achieving improved patient outcomes and near-term financial results.

    PubMed

    Lynch, J P; Forman, S A; Graff, S; Gunby, M C

    2000-07-01

    A managed care organization sought to achieve efficiencies in care delivery and cost savings by anticipating and better caring for its frail and least stable members. Time sequence case study of program intervention across an entire managed care population in its first year compared with the prior baseline year. Key attributes of the intervention included predictive registries of at-risk members based on existing data, relentless focus on the high-risk group, an integrated clinical and psychosocial approach to assessments and are planning, a reengineered care management process, secured Internet applications enabling rapid implementation and broad connectivity, and population-based outcomes metrics derived from widely used measures of resource utilization and functional status. Concentrating on the highest-risk group, which averaged just 1.1% prevalence in the total membership, yielded bottom line results. When the year before program implementation (July 1997 through June 1998) was compared with the subsequent year, the total population's annualized commercial admission rate was reduced 5.3%, and seniors' was reduced 3.0%. A claims-paid analysis exclusively of the highest-risk group revealed that their efficiencies and savings overwhelmingly contributed to the membershipwide effect. This subgroup's costs dropped 35.7% from preprogram levels of $2590 per member per month (excluding pharmaceuticals). During the same time, patient-derived cross-sectional functional status rose 12.5%. A sharply focused, Internet-deployed case management strategy achieved economic and functional status results on a population basis and produced systemwide savings in its first year of implementation.

  12. A Meta-Analysis of Constructivist Learning Approach on Learners' Academic Achievements, Retention and Attitudes

    ERIC Educational Resources Information Center

    Semerci, Çetin; Batdi, Veli

    2015-01-01

    This study attempts to answer the question "Does a Constructivist Learning Approach have any effect on learners' academic achievement, retention and attitude scores?" As a result of a systematic investigation of experimental studies carried out between 2002 and 2015 in national and international area, 324 (218 articles, 106 theses)…

  13. Detection of interaction articles and experimental methods in biomedical literature.

    PubMed

    Schneider, Gerold; Clematide, Simon; Rinaldi, Fabio

    2011-10-03

    This article describes the approaches taken by the OntoGene group at the University of Zurich in dealing with two tasks of the BioCreative III competition: classification of articles which contain curatable protein-protein interactions (PPI-ACT) and extraction of experimental methods (PPI-IMT). Two main achievements are described in this paper: (a) a system for document classification which crucially relies on the results of an advanced pipeline of natural language processing tools; (b) a system which is capable of detecting all experimental methods mentioned in scientific literature, and listing them with a competitive ranking (AUC iP/R > 0.5). The results of the BioCreative III shared evaluation clearly demonstrate that significant progress has been achieved in the domain of biomedical text mining in the past few years. Our own contribution, together with the results of other participants, provides evidence that natural language processing techniques have become by now an integral part of advanced text mining approaches.

  14. Experimental results of a new system using microwaves for vision correction

    NASA Astrophysics Data System (ADS)

    Ryan, Thomas P.; Pertaub, Radha; Meyers, Steven R.; Dresher, Russell P.; Scharf, Ronald

    2009-02-01

    Technology is in development to correct vision without the use of lasers or cutting of the eye. Many current technologies used to reshape the cornea are invasive, in that either RF needles are placed into the cornea or a flap is cut and then a laser used to ablate the cornea in the optical zone. Keraflex, a therapeutic microwave treatment, is a noninvasive, non-incisional refractive surgery procedure capable of treating myopia (nearsightedness). The goal is to create a predictable refractive change in the optical zone, while preserving the epithelium and deeper structures of the eye. A further goal is to avoid incisions and damage to the epithelium which both require a post-treatment healing period. Experimental work with fresh porcine eyes examined the following variables: duration of the RF pulse, RF power level, coolant amount and timing, electrode spacing, applanation force against the eye, initial eye temperature, and age of eye. We measured curvature changes of the eye with topography, Scheimpflug, Wavefront aberrometry or other means to characterize diopter change as an important endpoint. Other assessment includes evaluation of a fine white ring seen in the cornea following treatment. Dose studies have been done to correlate the treated region with energy delivered. The timing and dosing of energy and cooling were investigated to achieve the target diopter change in vision.

  15. The effects of collaborative concept mapping on the achievement, science self-efficacy and attitude toward science of female eighth-grade students

    NASA Astrophysics Data System (ADS)

    Ledger, Antoinette Frances

    This study sought to examine whether collaborative concept mapping would affect the achievement, science self-efficacy and attitude toward science of female eighth grade science students. The research questions are: (1) Will the use of collaborative concept mapping affect the achievement of female students in science? (2) Will the use of collaborative concept mapping affect the science self-efficacy of female students? (3) Will the use of collaborative concept mapping affect the attitudes of females toward science? The study was quasi-experimental and utilized a pretest-posttest design for both experimental and control groups. Eighth grade female and male students from three schools in a large northeastern school district participated in this study. The achievement test consisted of 10 multiple choice and two open-response questions and used questions from state-wide and national assessments as well as teacher-constructed items. A 29 item Likert type instrument (McMillan, 1992) was administered to measure science self-efficacy and attitude toward science. The study was of 12 weeks duration. During the study, experimental group students were asked to perform collaborative concept map construction in single sex dyads using specific terms designated by the classroom teacher and the researcher. During classroom visitations, student perceptions of collaborative concept mapping were collected and were used to provide insight into the results of the quantitative data analysis. Data from the pre and posttest instruments were analyzed for both experimental and control groups using t-tests. Additionally, the three teachers were interviewed and their perceptions of the study were also used to gain insight into the results of the study. The analysis of data showed that experimental group females showed significantly higher gains in achievement than control group females. An additional analysis of data showed experimental group males showed significantly greater gains in

  16. Supersonic Retropropulsion Experimental Results from the NASA Langley Unitary Plan Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Berry, Scott A.; Rhode, Matthew N.; Edquist, Karl T.; Player, Charles J.

    2011-01-01

    A new supersonic retropropulsion experimental effort, intended to provide code validation data, was recently completed in the Langley Research Center Unitary Plan Wind Tunnel Test Section 2 over the Mach number range from 2.4 to 4.6. The experimental model was designed using insights gained from pre-test computations, which were instrumental for sizing and refining the model to minimize tunnel wall interference and internal flow separation concerns. A 5-in diameter 70-deg sphere-cone forebody with a roughly 10-in long cylindrical aftbody was the baseline configuration selected for this study. The forebody was designed to accommodate up to four 4:1 area ratio supersonic nozzles. Primary measurements for this model were a large number of surface pressures on the forebody and aftbody. Supplemental data included high-speed Schlieren video and internal pressures and temperatures. The run matrix was developed to allow for the quantification of various sources of experimental uncertainty, such as random errors due to run-to-run variations and bias errors due to flow field or model misalignments. Preliminary results and observations from the test are presented, while detailed data and uncertainty analyses are ongoing.

  17. Cross-Domain Effects of Achievement Goals: Social Costs and Benefits

    ERIC Educational Resources Information Center

    Barrera, Andrea Eugenia; Schuster, Beate

    2018-01-01

    In this research, we examined cross-domain effects of achievement goals. In two experimental studies, we manipulated achievement goals and assessed social reactions towards a hypothetical (study 1) and a real (study 2) target. Measurement of social reactions included prosocial behaviours such as helping, sharing and cooperating with others.…

  18. Improving Achievement in Low-Performing Schools: Key Results for School Leaders

    ERIC Educational Resources Information Center

    Ward, Randolph E.; Burke, Mary Ann

    2004-01-01

    As accountability in schools becomes more crucial, educators are looking for comprehensive and innovative management practices that respond to challenges and realities of student academic achievement. In order to improve academic performance and the quality of instruction, the entire school community needs to be involved. This book provides six…

  19. Presenting the Students’ Academic Achievement Causal Model based on Goal Orientation

    PubMed Central

    NASIRI, EBRAHIM; POUR-SAFAR, ALI; TAHERI, MAHDOKHT; SEDIGHI PASHAKY, ABDULLAH; ASADI LOUYEH, ATAOLLAH

    2017-01-01

    Introduction: Several factors play a role in academic achievement, individual's excellence and capability to do actions and tasks that the learner is in charge of in learning areas. The main goal of this study was to present academic achievement causal model based on the dimensions of goal orientation and learning approaches among the students of Medical Science and Dentistry courses in Guilan University of Medical Sciences in 2013. Methods: This study is based on a cross-sectional model. The participants included 175 first and second students of the Medical and Dentistry schools in Guilan University of Medical Sciences selected by random cluster sampling [121 persons (69%) Medical Basic Science students and 54 (30.9%) Dentistry students]. The measurement tool included the Goal Orientation Scale of Bouffard and Study Process Questionnaire of Biggs) and the students’ Grade Point Average. The study data were analyzed using Pearson correlation coefficient and structural equations modeling. SPSS 14 and Amos were used to analyze the data. Results: The results indicated a significant relationship between goal orientation and learning strategies (P<0.05). In addition, the results revealed that a significant relationship exists between learning strategies[Deep Learning (r=0.37, P<0.05), Surface Learning (r=-0.21,P<0.05)], and academic achievement.The suggested model of research is fitted to the data of the research. Conclusion: Results showed that the students' academic achievement model fits with experimental data, so it can be used in learning principles which lead to students’ achievement in learning. PMID:28979914

  20. Impact of Jigsaw on the Achievement and Attitudes of Saudi Arabian Male High School Science Students

    NASA Astrophysics Data System (ADS)

    Alghamdi, Abdulmonem

    The aim of the study is to investigate the impact of cooperative learning instruction, specifically by using the Jigsaw instructional strategy on science achievement and attitudes towards science among 11th grade students. Based upon previous research literature, it was hypothesized that significant differences existed on gains between general science achievement of experimental group and control group. The quasi-experimental design was chosen for this study. The study sample consisted of 50 students of 11th grade class who were equally distributed among experimental group and control group, matched on the basic of their annual examination at general science scores. The students' achievement was measured through the implementation of 30-item achievement test used as a pretest, as well as a posttest and deferred (follow-up) test. The experiment group was taught through cooperative learning while control group was taught through the instructions of "traditional teaching". The material was used such as lesson plans, worksheets and quizzes, designed to implement Jigsaw as a cooperative learning methodology. For the attitude scale towards science, a published 30-item Likert scale called Test of Science Related Attitudes (TOSRA) has been translated to Arabic in order to determine the students' attitudes ranging between strongly agree to strongly disagree. The data were analyzed through repeated measure analysis and multivariate analysis of variance with a .05 selected level of significance. The results of this study showed that using Jigsaw as a cooperative learning strategy has improved the students' achievement for the benefit of the experimental group. However, there was no significant change on the students' attitudes towards science for both groups, where the scores of all the attitude subscales were at or near the neutral level.

  1. Effect of Using Mathematics Laboratory in Teaching Mathematics on the Achievement of Mathematics Students

    ERIC Educational Resources Information Center

    Okigbo, Ebele C.; Osuafor, Abigail M.

    2008-01-01

    The study investigated the effect of using mathematics laboratory in teaching on students' achievement in Junior Secondary School Mathematics. A total of 100 JS 3 Mathematics students were involved in the study. The study is a quasi-experimental research. Results were analyzed using mean, standard deviation and analysis of covariance (ANCOVA).…

  2. Why Evaluations Fail: To Achieve Meaningful Results, Address These Common Challenges

    ERIC Educational Resources Information Center

    Killion, Joellen

    2017-01-01

    Evaluation of professional learning illuminates the interactions that occur in the implementation of planned learning experiences and the necessary supports designed to improve professional practice and its effects on students. It investigates how a set of actions designed to achieve defined short- and long-term outcomes occur over time and how…

  3. Experimental result analysis for scaled model of UiTM tailless blended wing-body (BWB) Baseline 7 unmanned aerial vehicle (UAV)

    NASA Astrophysics Data System (ADS)

    Nasir, R. E. M.; Ahmad, A. M.; Latif, Z. A. A.; Saad, R. M.; Kuntjoro, W.

    2017-12-01

    Blended wing-body (BWB) aircraft having planform configuration similar to those previously researched and published by other researchers does not guarantee that an efficient aerodynamics in term of lift-to-drag ratio can be achieved. In this wind tunnel experimental study, BWB half model is used. The model is also being scaled down to 71.5% from the actual size. Based on the results, the maximum lift coefficient is found to be 0.763 when the angle is at 27.5° after which the model starts to stall. The minimum drag coefficient is 0.014, measured at zero angle of attack. The corrected lift-to-drag ratio (L/D) is 15.9 at angle 7.8°. The scaled model has a big flat surface that surely gives an inaccurate data but the data obtained shall give some insights for future perspective towards the BWB model being tested.

  4. Gaseous Sulfate Solubility in Glass: Experimental Method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bliss, Mary

    2013-11-30

    Sulfate solubility in glass is a key parameter in many commercial glasses and nuclear waste glasses. This report summarizes key publications specific to sulfate solubility experimental methods and the underlying physical chemistry calculations. The published methods and experimental data are used to verify the calculations in this report and are expanded to a range of current technical interest. The calculations and experimental methods described in this report will guide several experiments on sulfate solubility and saturation for the Hanford Waste Treatment Plant Enhanced Waste Glass Models effort. There are several tables of sulfate gas equilibrium values at high temperature tomore » guide experimental gas mixing and to achieve desired SO3 levels. This report also describes the necessary equipment and best practices to perform sulfate saturation experiments for molten glasses. Results and findings will be published when experimental work is finished and this report is validated from the data obtained.« less

  5. The experimental results of a self tuning adaptive controller using online frequency identification. [for Galileo spacecraft

    NASA Technical Reports Server (NTRS)

    Chiang, W.-W.; Cannon, R. H., Jr.

    1985-01-01

    A fourth-order laboratory dynamic system featuring very low structural damping and a noncolocated actuator-sensor pair has been used to test a novel real-time adaptive controller, implemented in a minicomputer, which consists of a state estimator, a set of state feedback gains, and a frequency-locked loop for real-time parameter identification. The adaptation algorithm employed can correct controller error and stabilize the system for more than 50 percent variation in the plant's natural frequency, compared with a 10 percent stability margin in frequency variation for a fixed gain controller having the same performance as the nominal plant condition. The very rapid convergence achievable by this adaptive system is demonstrated experimentally, and proven with simple, root-locus methods.

  6. Vibration Based Crack Detection in a Rotating Disk. Part 2; Experimental Results

    NASA Technical Reports Server (NTRS)

    Gyekenyesi, Andrew L.; Sawicki, Jerzy T.; Martin, Richard E.; Haase, Wayne C.; Baaklini, George

    2005-01-01

    This paper describes the experimental results concerning the detection of a crack in a rotating disk. The goal was to utilize blade tip clearance and shaft vibration measurements to monitor changes in the system's center of mass and/or blade deformation behaviors. The concept of the approach is based on the fact that the development of a disk crack results in a distorted strain field within the component. As a result, a minute deformation in the disk's geometry as well as a change in the system's center of mass occurs. Here, a notch was used to simulate an actual crack. The vibration based experimental results failed to identify the existence of a notch when utilizing the approach described above, even with a rather large, circumferential notch (l.2 in.) located approximately mid-span on the disk (disk radius = 4.63 in. with notch at r = 2.12 in.). This was somewhat expected, since the finite element based results in Part 1 of this study predicted changes in blade tip clearance as well as center of mass shifts due to a notch to be less than 0.001 in. Therefore, the small changes incurred by the notch could not be differentiated from the mechanical and electrical noise of the rotor system. Although the crack detection technique of interest failed to identify the existence ofthe notch, the vibration data produced and captured here will be utilized in upcoming studies that will focus on different data mining techniques concerning damage detection in a disk.

  7. Conceptual achievement of 1GBq activity in a Plasma Focus driven system.

    PubMed

    Tabbakh, Farshid; Sadat Kiai, Seyed Mahmood; Pashaei, Mohammad

    2017-11-01

    This is an approach to evaluate the radioisotope production by means of typical dense plasma focus devices. The production rate of the appropriate positron emitters, F-18, N-13 and O-15 has been studied. The beam-target mechanism was simulated by GEANT4 Monte Carlo tool using QGSP_BIC and QGSP_INCLXX physic models as comparison. The results for positron emitters have been evaluated by reported experimental data and found conformity between simulations and experimental reports that leads to using this code as a reliable tool in optimizing the DPF driven systems for achieving to 1GBq activity of produced radioisotope. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Uncertainties and understanding of experimental and theoretical results regarding reactions forming heavy and superheavy nuclei

    NASA Astrophysics Data System (ADS)

    Giardina, G.; Mandaglio, G.; Nasirov, A. K.; Anastasi, A.; Curciarello, F.; Fazio, G.

    2018-02-01

    Experimental and theoretical results of the PCN fusion probability of reactants in the entrance channel and the Wsur survival probability against fission at deexcitation of the compound nucleus formed in heavy-ion collisions are discussed. The theoretical results for a set of nuclear reactions leading to formation of compound nuclei (CNs) with the charge number Z = 102- 122 reveal a strong sensitivity of PCN to the characteristics of colliding nuclei in the entrance channel, dynamics of the reaction mechanism, and excitation energy of the system. We discuss the validity of assumptions and procedures for analysis of experimental data, and also the limits of validity of theoretical results obtained by the use of phenomenological models. The comparison of results obtained in many investigated reactions reveals serious limits of validity of the data analysis and calculation procedures.

  9. What is the Effect of Case-Based Learning on the Academic Achievement of Students on the Topic of "Biochemical Oxygen Demand?"

    NASA Astrophysics Data System (ADS)

    Günter, Tuğçe; Alpat, Sibel Kılınç

    2017-11-01

    The purpose of this study was to investigate the effect of the case-based learning (CBL) method used in "biochemical oxygen demand (BOD)," which is a topic taught in the environmental chemistry course, at Dokuz Eylul University, on the academic achievement and opinions of students. The research had a quasi-experimental design and the study group consisted of 4th and 5th grade students (N = 18) attending the Chemistry Teaching Program in a university in Izmir. The "Biochemical Oxygen Demand Achievement Test (BODAT)" and the structured interview form were used as data collection tools. The results of BODAT post-test showed the higher increase in the achievement scores of the experimental group may be an indication of the effectiveness of the CBL method in improving academic achievement in the relevant topic. In addition, the experimental and control group students had positive opinions regarding the method, the scenario, and the material. The students found the method, the scenario, and the material to be interesting, understandable/instructional, relatable with everyday life, suitable for the topic, and enhancing active participation.

  10. The influence of formative assessments on student motivation, achievement, and conceptual change

    NASA Astrophysics Data System (ADS)

    Yin, Yue

    2005-07-01

    This study connected research on formative assessment, motivation, and conceptual change. In particular, it examined three research questions: (1) Can formative assessment improve students' motivational beliefs? (2) Can formative assessment improve students' achievement in science and bring about conceptual change? and (3) Are students' science achievement and conceptual change correlated with their motivational beliefs? Formative assessment in this study refers to assessments embedded in an inquiry-based curriculum. To answer those questions, a randomized experiment was conducted. One thousand and two 6th or 7th graders of 12 teachers in 12 different schools in six states participated in the study. The 12 teachers were matched in pairs and randomly assigned to the experimental and control group. The experimental group employed embedded formative assessments while teaching a science curriculum unit and the control group taught the same unit without formative assessments. All the students were given a motivation survey and one or more achievement tests at pre- and posttest. By comparing the experimental and control students' motivation and achievement scores at pretest and posttest, I examined whether the formative assessment treatment affected students' motivation, learning, and conceptual change. By correlating students' posttest motivation, achievement as well as conceptual change scores, I examined whether students' motivation was related to their achievement and conceptual change. Analyses indicated that, the embedded assessments used by the experimental group did not significantly influence students' motivation, achievement, or conceptual change compared to students in the control group. Most motivation beliefs were correlated with students' achievement in a way similar to what has been reported in the literature. They were not correlated with students' conceptual change scores as hypothesized. Teachers, as well as some contextual factors associated with

  11. Experimental and raytrace results for throat-to-throat compound parabolic concentrators

    NASA Technical Reports Server (NTRS)

    Leviton, D. B.; Leitch, J. W.

    1986-01-01

    Compound parabolic concentrators are nonimaging cone-shaped optics with useful angular transmission characteristics. Two cones used throat-to-throat accept radiant flux within one well-defined acceptance angle and redistribute it into another. If the entrance cone is fed with Lambertian flux, the exit cone produces a beam whose half-angle is the exit cone's acceptance angle and whose cross section shows uniform irradiance from near the exit mouth to infinity. (The pair is a beam angle transformer). The design of one pair of cones is discussed, also an experiment to map the irradiance of the emergent beam, and a raytracing program which models the cones fed by Lambertian flux. Experimental results compare favorably with raytrace results.

  12. LBE water interaction in sub-critical reactors: First experimental and modelling results

    NASA Astrophysics Data System (ADS)

    Ciampichetti, A.; Agostini, P.; Benamati, G.; Bandini, G.; Pellini, D.; Forgione, N.; Oriolo, F.; Ambrosini, W.

    2008-06-01

    This paper concerns the study of the phenomena involved in the interaction between LBE and pressurised water which could occur in some hypothetical accidents in accelerator driven system type reactors. The LIFUS 5 facility was designed and built at ENEA-Brasimone to reproduce this kind of interaction in a wide range of conditions. The first test of the experimental program was carried out injecting water at 70 bar and 235 °C in a reaction vessel containing LBE at 1 bar and 350 °C. A pressurisation up to 80 bar was observed in the test section during the considered transient. The SIMMER III code was used to simulate the performed test. The calculated data agree in a satisfactory way with the experimental results giving confidence in the possibility to use this code for safety analyses of heavy liquid metal cooled reactors.

  13. Drying in porous media with gravity-stabilized fronts: experimental results.

    PubMed

    Yiotis, A G; Salin, D; Tajer, E S; Yortsos, Y C

    2012-08-01

    In a recent paper [Yiotis et al., Phys. Rev. E 85, 046308 (2012)] we developed a model for the drying of porous media in the presence of gravity. It incorporated effects of corner film flow, internal and external mass transfer, and the effect of gravity. Analytical results were derived when gravity opposes drying and hence leads to a stable percolation drying front. In this paper, we test the theory using laboratory experiments. A series of isothermal drying experiments in glass bead packings saturated with volatile hydrocarbons is conducted. The transparent glass cells containing the packing allow for the visual monitoring of the phase distribution patterns below the surface, including the formation of liquid films, as the gaseous phase invades the pore space, and for the control of the thickness of the diffusive mass boundary layer over the packing. The experimental results agree very well with theory, provided that the latter is generalized to account for the effects of corner roundness in the film region (which was neglected in the theoretical part). We demonstrate the existence of an early constant rate period (CRP), which lasts as long as the films saturate the surface of the packing, and of a subsequent falling rate period (FRP), which begins practically after the detachment of the film tips from the external surface. During the CRP, the process is controlled by diffusion within the stagnant gaseous phase in the upper part of the cells, yielding a Stefan tube problem solution. During the FRP, the process is controlled by diffusion within the packing, with a drying rate inversely proportional to the observed position of the film tips in the cell. Theoretical and experimental results compare favorably for a specific value of the roundness of the films, which is found to be constant and equal to 0.2 for various conditions, and verify the theoretical dependence on the capillary Ca(f), Bond Bo, and Sherwood Sh numbers.

  14. Experimental and numerical researches of duplex burnishing process in aspect of achieved productive quality of the product

    NASA Astrophysics Data System (ADS)

    Patyk, Radoslaw; Kukielka, Leon; Kaldunski, Pawel; Bohdal, Lukasz; Chodor, Jaroslaw; Kulakowska, Agnieszka; Kukielka, Krzysztof; Nagnajewicz, Slawomir

    2018-05-01

    The paper presents the results of experimental researches and numerical simulations of the duplex burnishing process. During duplex burnishing process the treatment is carry out in two stages. In the first stage - on the semi-fabrication surface, the regular asperities are embossed with triangular, symmetrical, periodic outline. In the second stage the asperities are burnished (smooth burnishing) till the needed asperities equalized, resulting in a smooth and strengthened surface layer. The implementation of such technology results in receiving of a new surface layer characterized by favorable functional properties, particularly increased resistance to fatigue wear.

  15. Experimental Results From the Thermal Energy Storage-1 (TES-1) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Jacqmin, David

    1995-01-01

    The Thermal Energy Storage (TES) experiments are designed to provide data to help researchers understand the long-duration microgravity behavior of thermal energy storage fluoride salts that undergo repeated melting and freezing. Such data, which have never been obtained before, have direct application to space-based solar dynamic power systems. These power systems will store solar energy in a thermal energy salt, such as lithium fluoride (LiF) or a eutectic of lithium fluoride/calcium difluoride (LiF-CaF2) (which melts at a lower temperature). The energy will be stored as the latent heat of fusion when the salt is melted by absorbing solar thermal energy. The stored energy will then be extracted during the shade portion of the orbit, enabling the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes have been developed to predict the performance of a spacebased solar dynamic power system. However, the analytical predictions must be verified experimentally before the analytical results can be used for future space power design applications. Four TES flight experiments will be used to obtain the needed experimental data. This article focuses on the flight results from the first experiment, TES-1, in comparison to the predicted results from the Thermal Energy Storage Simulation (TESSIM) analytical computer code.

  16. Can paying for results help to achieve the Millennium Development Goals? A critical review of selected evaluations of results-based financing.

    PubMed

    Oxman, Andrew D; Fretheim, Atle

    2009-08-01

    Results-based financing (RBF) refers to the transfer of money or material goods conditional on taking a measurable action or achieving a predetermined performance target. RBF is being promoted for helping to achieve the Millennium Development Goals (MDGs). We undertook a critical appraisal of selected evaluations of RBF schemes in the health sector in low and middle-income countries (LMIC). In addition, key informants were interviewed to identify literature relevant to the use of RBF in the health sector in LMIC, key examples, evaluations, and other key informants. The use of RBF in LMIC has commonly been a part of a package that may include increased funding, technical support, training, changes in management, and new information systems. It is not possible to disentangle the effects of financial incentives as one element of RBF schemes, and there is very limited evidence of RBF per se having an effect. RBF schemes can have unintended effects. When RBF schemes are used, they should be designed carefully, including the level at which they are targeted, the choice of targets and indicators, the type and magnitude of incentives, the proportion of financing that is paid based on results, and the ancillary components of the scheme. For RBF to be effective, it must be part of an appropriate package of interventions, and technical capacity or support must be available. RBF schemes should be monitored for possible unintended effects and evaluated using rigorous study designs. © 2009 Blackwell Publishing Asia Pty Ltd and Chinese Cochrane Center, West China Hospital of Sichuan University.

  17. Out-of-plane buckling of pantographic fabrics in displacement-controlled shear tests: experimental results and model validation

    NASA Astrophysics Data System (ADS)

    Barchiesi, Emilio; Ganzosch, Gregor; Liebold, Christian; Placidi, Luca; Grygoruk, Roman; Müller, Wolfgang H.

    2018-01-01

    Due to the latest advancements in 3D printing technology and rapid prototyping techniques, the production of materials with complex geometries has become more affordable than ever. Pantographic structures, because of their attractive features, both in dynamics and statics and both in elastic and inelastic deformation regimes, deserve to be thoroughly investigated with experimental and theoretical tools. Herein, experimental results relative to displacement-controlled large deformation shear loading tests of pantographic structures are reported. In particular, five differently sized samples are analyzed up to first rupture. Results show that the deformation behavior is strongly nonlinear, and the structures are capable of undergoing large elastic deformations without reaching complete failure. Finally, a cutting edge model is validated by means of these experimental results.

  18. Effects of Literature-Based Reading Instruction of the Reading Achievement of Hispanic First-Grade Students.

    ERIC Educational Resources Information Center

    Carrasco, Miguel A.

    A study investigated the effects of the literature-based reading instruction on the reading achievement of Mexican-American first graders in Spanish. Using a posttest-only control group design and "t" test for independent samples, results indicated that after three months the experimental group of 30 students (attending a 100% Hispanic…

  19. Swinging Atwood Machine: Experimental and numerical results, and a theoretical study

    NASA Astrophysics Data System (ADS)

    Pujol, O.; Pérez, J. P.; Ramis, J. P.; Simó, C.; Simon, S.; Weil, J. A.

    2010-06-01

    A Swinging Atwood Machine ( SAM) is built and some experimental results concerning its dynamic behaviour are presented. Experiments clearly show that pulleys play a role in the motion of the pendulum, since they can rotate and have non-negligible radii and masses. Equations of motion must therefore take into account the moment of inertia of the pulleys, as well as the winding of the rope around them. Their influence is compared to previous studies. A preliminary discussion of the role of dissipation is included. The theoretical behaviour of the system with pulleys is illustrated numerically, and the relevance of different parameters is highlighted. Finally, the integrability of the dynamic system is studied, the main result being that the machine with pulleys is non-integrable. The status of the results on integrability of the pulley-less machine is also recalled.

  20. Achievements and challenges in structural bioinformatics and computational biophysics

    PubMed Central

    Samish, Ilan; Bourne, Philip E.; Najmanovich, Rafael J.

    2015-01-01

    Motivation: The field of structural bioinformatics and computational biophysics has undergone a revolution in the last 10 years. Developments that are captured annually through the 3DSIG meeting, upon which this article reflects. Results: An increase in the accessible data, computational resources and methodology has resulted in an increase in the size and resolution of studied systems and the complexity of the questions amenable to research. Concomitantly, the parameterization and efficiency of the methods have markedly improved along with their cross-validation with other computational and experimental results. Conclusion: The field exhibits an ever-increasing integration with biochemistry, biophysics and other disciplines. In this article, we discuss recent achievements along with current challenges within the field. Contact: Rafael.Najmanovich@USherbrooke.ca PMID:25488929

  1. The Effects of Training in Timing and Rhythm on Reading Achievement

    ERIC Educational Resources Information Center

    Taub, Gordon E.; Lazarus, Philip J.

    2012-01-01

    This study investigated the relationship between improvement in students' timing/rhythmicity and reading achievement. Two hundred eighty high school-age participants completed pre- and post-test measures from the Woodcock-Johnson Tests of Achievement-III (Woodcock, McGrew, & Mather, 2001). Students in the experimental group participated in a…

  2. Reading Achievement State by State, 1999. Goal 3: Student Achievement and Citizenship.

    ERIC Educational Resources Information Center

    National Education Goals Panel (ED), Washington, DC.

    Noting that performance at the highest levels of achievement on the National Assessment of Educational Progress (NAEP) is evidence that students have demonstrated competency over challenging subject matter and achieved the third National Educational Goal, this report presents the most up-to-date results in reading achievement for the states and…

  3. NON-INTELLECTIVE PREDICTORS OF ACHIEVEMENT IN COLLEGE.

    ERIC Educational Resources Information Center

    NICHOLS, ROBERT C.

    SCALES FOR PREDICTING 1ST-YEAR COLLEGE GRADES AND EXTRACURRICULAR ACHIEVEMENT WERE DEVELOPED BY ITEM ANALYSIS FROM EACH OF FOUR ITEM POOLS--THE CALIFORNIA PSYCHOLOGICAL INVENTORY (CPI), THE VOCATIONAL PREFERENCE INVENTORY (VPI), AN ADJECTIVE CHECK LIST (ACL), AND AN EXPERIMENTAL OBJECTIVE BEHAVIOR INVENTORY (OBI)--USING A SAMPLE OF 1,013 NATIONAL…

  4. Shuttle Return To Flight Experimental Results: Protuberance Effects on Boundary Layer Transition

    NASA Technical Reports Server (NTRS)

    Liechty, Derek S.; Berry, Scott A.; Horvath, Thomas J.

    2006-01-01

    The effect of isolated roughness elements on the windward boundary layer of the Shuttle Orbiter has been experimentally examined in the Langley Aerothermodynamic Laboratory in support of an agency-wide effort to prepare the Shuttle Orbiter for return to flight. This experimental effort was initiated to provide a roughness effects database for developing transition criteria to support on-orbit decisions to repair damage to the thermal protection system. Boundary layer transition results were obtained using trips of varying heights and locations along the centerline and attachment lines of 0.0075-scale models. Global heat transfer images using phosphor thermography of the Orbiter windward surface and the corresponding heating distributions were used to infer the state of the boundary layer (laminar, transitional, or turbulent). The database contained within this report will be used to formulate protuberance-induced transition correlations using predicted boundary layer edge parameters.

  5. Experimental BCAS Performance Results

    DOT National Transportation Integrated Search

    1978-07-01

    The results of the (Litchford) Beacon-based Collision Avoidance System concept feasibility evaluation are reported. Included are a description of the concept, analysis and flight test results. The system concept is based on the range and bearing meas...

  6. Experimental and simulational result multipactors in 112 MHz QWR injector

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xin, T.; Ben-Zvi, I.; Belomestnykh, S.

    2015-05-03

    The first RF commissioning of 112 MHz QWR superconducting electron gun was done in late 2014. The coaxial Fundamental Power Coupler (FPC) and Cathode Stalk (stalk) were installed and tested for the first time. During this experiment, we observed several multipacting barriers at different gun voltage levels. The simulation work was done within the same range. The comparison between the experimental observation and the simulation results are presented in this paper. The observations during the test are consisted with the simulation predictions. We were able to overcome most of the multipacting barriers and reach 1.8 MV gun voltage under pulsedmore » mode after several round of conditioning processes.« less

  7. Blanking and piercing theory, applications and recent experimental results

    NASA Astrophysics Data System (ADS)

    Zaid, Adnan l. O.

    2014-06-01

    Blanking and piercing are manufacturing processes by which certain geometrical shapes are sheared off a sheet metal. If the sheared off part is the one required, the processes referred to as blanking and if the remaining part in the sheet is the one required, the process is referred to as piercing. In this paper, the theory and practice of these processes are reviewed and discussed The main parameters affecting these processes are presented and discussed. These include: the radial clearance percentage, punch and die geometrical parameters, for example punch and die profile radii. The abovementioned parameters on the force and energy required to effect blanking together with their effect on the quality of the products are also presented and discussed. Recent experimental results together with photomacrographs and photomicrographs are also included and discussed. Finally, the effect of punch and die wear on the quality of the blanks is alsogiven and discussed.

  8. Experimental and analytical studies of high heat flux components for fusion experimental reactor

    NASA Astrophysics Data System (ADS)

    Araki, Masanori

    1993-03-01

    In this report, the experimental and analytical results concerning the development of plasma facing components of ITER are described. With respect to developing high heat removal structures for the divertor plates, an externally-finned swirl tube was developed based on the results of critical heat flux (CHF) experiments on various tube structures. As the result, the burnout heat flux, which also indicates incident CHF, of 41 (+/-) 1 MW/sq m was achieved in the externally-finned swirl tube. The applicability of existing CHF correlations based on uniform heating conditions was evaluated by comparing the CHF experimental data with the smooth and the externally-finned tubes under one-sided heating condition. As the results, experimentally determined CHF data for straight tube show good agreement, for the externally-finned tube, no existing correlations are available for prediction of the CHF. With respect to the evaluation of the bonds between carbon-based material and heat sink metal, results of brazing tests were compared with the analytical results by three dimensional model with temperature-dependent thermal and mechanical properties. Analytical results showed that residual stresses from brazing can be estimated by the analytical three directional stress values instead of the equivalent stress value applied. In the analytical study on the separatrix sweeping for effectively reducing surface heat fluxes on the divertor plate, thermal response of the divertor plate was analyzed under ITER relevant heat flux conditions and has been tested. As the result, it has been demonstrated that application of the sweeping technique is very effective for improvement in the power handling capability of the divertor plate and that the divertor mock-up has withstood a large number of additional cyclic heat loads.

  9. Effects of individualized assignments on biology achievement

    NASA Astrophysics Data System (ADS)

    Kremer, Philip L.

    A pretest-posttest, randomized, two groups, experimental, factorial design compared effects of detailed and nondetailed assignments on biology achievement over seven and a half months. Detailed assignments (favoring field independence and induction) employed block diagrams and stepwise directions. Nondetailed assignments (favoring field dependence and deduction) virtually lacked these. The accessible population was 101 tenth grade preparatory school male students. The 95 students enrolled in first year biology constituted the sample. Two by three ANOVA was done on residualized posttest score means of the students. Totally, the detailed students achieved significantly higher than the nondetailed students. This significantly higher achievement was only true of detailed students in the middle thirds of the deviation intelligence quotient (DIQ) range and of the grade point average (G.P.A.) range after the breakdown into upper, middle, and lower thirds of intellectual capability (ability and achievement). The upper third detailed DIQ grouping indirectly achieved higher than its peers, whereas the lower detailed DIQ third achieved lower than its peers. Thus, high capability students apparently benefit from flow and block diagrams, inductions, field independence, and high structure, whereas low capability students may be hindered by these.

  10. Experimental results on atomic oxygen corrosion of silver

    NASA Technical Reports Server (NTRS)

    Fromhold, Albert T.

    1988-01-01

    The results of an experimental study of the reaction kinetics of silver with atomic oxygen in 10 degree increments over the temperature range of 0 to 70 C is reported. The silver specimens, of the order of 10,000 A in thickness, were prepared by thermal evaporation onto 3 inch diameter polished silicon wafers. There were later sliced into pieces having surface areas of the order of 1/4 to 1/2 square inch. Atomic oxygen was generated by a gas discharge in a commercial plasmod asher operating in the megahertz frequency range. The sample temperature within the chamber was controlled by means of a thermoelectric unit. Exposure of the silver specimens to atomic oxygen was incremental, with oxide film thickness measurements being carried out between exposures by means of an automated ellipsometer. For the early growth phase, the data can be described satisfactorily by a logarithmic growth law: the oxide film thickness increases as the logarithm of the exposure time. Furthermore, the oxidation process is thermally activated, the rate increasing with increasing temperature. However, the empirical activation energy parameter deduced from Arrhenius plots is quite low, being of the order of 0.1 eV.

  11. Shuttle Upper Atmosphere Mass Spectrometer Experimental Flight Results

    NASA Technical Reports Server (NTRS)

    Blanchard, R. C.; Ozoroski, Thomas A.; Nicholson, John Y.

    1994-01-01

    Calibrated pressure measurements for species with mass-to-charge ratios up to 50 amu/e(-) were obtained trom the shuttle upper atmosphere mass spectrometer experiment during re-entry on the STS-35 mission. The principal experimental objective is to obtain measurements of freestream density in the hypersonic rarefied flow flight regime. Data were collected from 180 to about 87 km. However, data above 115 km were contaminated from a source of gas emanating from pressure transdueers connected in parallel to the mass spectrometer. At lower altitudes, the pressure transducer data are compared to the mass spectrometer total pressure with excellent agreement. Near the orifice entrance, a significant amount of CO2 was generated from chemical reactions. The freestream density in the rarefied flow flight regime is calculated using an orifice pressure coefficient model based upon direct simulation Monte Carlo results. This density, when compared with the 1976 U.S. Standard Atmosphere model, exhibits the wavelike nature seen on previous flights using accelerometry. Selected spectra are presented at higher altitudes (320 km) showing the effects of the ingestion of gases from a forward fuselage fuel dump.

  12. Effects of Traditional, Blended and E-Learning on Students' Achievement in Higher Education

    ERIC Educational Resources Information Center

    Al-Qahtani, Awadh A. Y.; Higgins, S. E.

    2013-01-01

    The study investigates the effect of e-learning, blended learning and classroom learning on students' achievement. Two experimental groups together with a control group from Umm Al-Qura University in Saudi Arabia were identified randomly. To assess students' achievement in the different groups, pre- and post-achievement tests were used. The…

  13. Effects of Writing Instruction on Kindergarten Students' Writing Achievement: An Experimental Study

    ERIC Educational Resources Information Center

    Jones, Cindy D'On

    2015-01-01

    This full-year experimental study examined how methods of writing instruction contribute to kindergarten students' acquisition of foundational and compositional early writing skills. Multiple regression with cluster analysis was used to compare 3 writing instructional groups: an interactive writing group, a writing workshop group, and a…

  14. Artificial cochlea and acoustic black hole travelling waves observation: Model and experimental results

    NASA Astrophysics Data System (ADS)

    Foucaud, Simon; Michon, Guilhem; Gourinat, Yves; Pelat, Adrien; Gautier, François

    2014-07-01

    An inhomogeneous fluid structure waveguide reproducing passive behaviour of the inner ear is modelled with the help of the Wentzel-Kramers-Brillouin method. A physical setup is designed and built. Experimental results are compared with a good correlation to theoretical ones. The experimental setup is a varying width plate immersed in fluid and terminated with an acoustic black hole. The varying width plate provides a spatial repartition of the vibration depending on the excitation frequency. The acoustic black hole is made by decreasing the plate's thickness with a quadratic profile and by covering this region with a thin film of viscoelastic material. Such a termination attenuates the flexural wave reflection at the end of the waveguide, turning standing waves into travelling waves.

  15. EASE (Experimental Assembly of Structures in EVA) overview of selected results

    NASA Technical Reports Server (NTRS)

    Akin, David L.

    1987-01-01

    Experimental Assembly of Structures in EVA (EASE) objectives, experimental protocol, neutral buoyancy simulation, task time distribution, assembly task performance, metabolic rate/biomedical readouts are summarized. This presentation is shown in charts, figures, and graphs.

  16. Experimental Results of OH Regime Investigation in Globus-M Spherical Torus

    NASA Astrophysics Data System (ADS)

    Golant, Victor; Gusev, Vasily; Levin, Roman; Petrov, Yuriy; Sakharov, Nikolay

    2001-10-01

    Plasma parameters were measured in novel spherical torus Globus-M in highly shaped plasmas with aspect ratio, A > 1.5, elongation, k < 1.9, triangularity < 0.5. Plasma column was created by direct induction method with the currents up to Ip 0.3 MA in the magnetic field, Bt - 0.08 - 0.5 T. In Globus-M spherical torus plasma column is closely fitted into the vacuum vessel and wall conditioning technology described in [1] was used to achieve good plasma performance. Plasma experiments were focused around achievement of ultimate OH regimes allowed by power supplies. The operational limits of the device were investigated. In the regime with extreme low q(cy1) < 1 and high normalized current > 4, the plasma current of almost 100kA was sustained transiently in low magnetic field 800 Gs. The first results on stability analysis with numerical code are presented. The runaway electrons behavior was studied in spherical tokamak conditions. Influence of plasma current and density ramp-up speeds, MHD events on plasma performance and stability was demonstrated. Magnetic reconstruction was performed with EFIT version adopted for PC simulations. Plans for auxiliary heating and current drive are discussed. 1. V.K. Gusev, …, V.E. Golant, et al., Nucl. Fusion 41, No 7, (2001), to be published

  17. Learning nanotechnology with texts and comics: the impacts on students of different achievement levels

    NASA Astrophysics Data System (ADS)

    Lin, Shu-Fen; Lin, Huann-shyang

    2016-05-01

    Comics are popular with adolescents because of their features of humor, narrative, and visual imagery. The purposes of this study were to examine the learning outcomes and emotional perceptions of reading a science comic book and a science text booklet for students of different levels of achievement, and to explore the main factors of the two media which attract high-school students to learn science. A mixed-method quasi-experimental design was adopted. The participants were 697 grade ten students from eight schools with different levels of academic achievement. Two similar classes in each of the eight schools were assigned as the comic group or the text group. The results indicated that the science comic book benefited medium achievers more than the science text booklet did, but the contrary result was found for the high achievers. In comparison, the two media benefited the low achievers equally, but both had only a limited effect due to the students' lack of prior knowledge. We conclude four kinds of evidence, including perceived difficulty of comprehension, reasons for interest/disinterest, emotional perceptions of learning science, and learning time, to support the phenomenon of the learning benefit of media specific to certain achievers' science learning.

  18. Promoting walking to school: results of a quasi-experimental trial.

    PubMed

    McKee, Rosie; Mutrie, Nanette; Crawford, Fiona; Green, Brian

    2007-09-01

    To assess the impact of a combined intervention on children's travel behaviour, stage of behavioural change and motivations for and barriers to actively commuting to school. A quasi-experimental trial involving pre- and post-intervention mapping of routes to school by active and inactive mode of travel and surveys of "stage of behaviour change" and motivations for and barriers to actively commuting to school. The intervention school participated in a school-based active travel project for one school term. Active travel was integrated into the curriculum and participants used interactive travel-planning resources at home. The control school participated in before and after measurements but did not receive the intervention. Two primary schools in Scotland with similar socioeconomic and demographic profiles. Two classes of primary 5 children and their families and teachers. Post intervention, the mean distance travelled to school by walking by intervention children increased significantly from baseline, from 198 to 772 m (389% increase). In the control group mean distance walked increased from 242 to 285 m (17% increase). The difference between the schools was significant (t (38) = -4.679, p<0.001 (95% confidence interval -315 to -795 m)). Post intervention, the mean distance travelled to school by car by intervention children reduced significantly from baseline, from 2018 to 933 m (57.5% reduction). The mean distance travelled to school by car by control children increased from baseline, from 933 to 947 m (1.5% increase). The difference in the change between schools was significant (t (32) = 4.282, p<0.001 (95% confidence interval 445 to 1255 m)). Intervention was effective in achieving an increase in the mean distance travelled by active mode and a reduction in the mean distance travelled by inactive mode on school journey.

  19. Effects of collaboration and inquiry on reasoning and achievement in biology

    NASA Astrophysics Data System (ADS)

    Jensen, Jamie Lee

    The primary purpose of the present study was to compare the effectiveness of two collaborative grouping strategies and two instructional methods in terms of gains in reasoning ability and achievement in college biology. In order to do so, a quasi-experimental study was performed in which students were placed in one of four treatment conditions: heterogeneous grouping within inquiry instruction, homogeneous grouping within inquiry instruction, heterogeneous grouping within non-inquiry instruction, and homogeneous grouping within non-inquiry instruction. Students were placed in groups based on initial reasoning level. Reasoning levels and achievement gains were assessed at the end of the study. Results showed that within non-inquiry instruction, heterogeneous mean group scores were higher in both reasoning and achievement than homogeneous groups. In contrast, within inquiry instruction, homogeneous mean group scores were higher in both reasoning and achievement. Inquiry instruction, as a whole, significantly outperformed non-inquiry instruction in the development of reasoning ability. Within inquiry instruction, low-ability students had significantly greater reasoning gains when grouped homogeneously. These results support Piaget's developmental theory and contradict Vygotsky's developmental theory. These results also suggest that the success of one grouping strategy over another is highly dependent upon the nature of instruction, which may be a cause for such conflicting views on grouping strategies within the educational literature. In addition, inquiry instruction led to students having greater confidence in their reasoning ability as well as a more positive attitude toward collaboration. Instructional implications are discussed.

  20. The Effect of Guided-Inquiry Instruction on 6th Grade Turkish Students' Achievement, Science Process Skills, and Attitudes Toward Science

    NASA Astrophysics Data System (ADS)

    Koksal, Ela Ayse; Berberoglu, Giray

    2014-01-01

    The purpose of this study is to investigate the effectiveness of guided-inquiry approach in science classes over existing science and technology curriculum in developing content-based science achievement, science process skills, and attitude toward science of grade level 6 students in Turkey. Non-equivalent control group quasi-experimental design was used to investigate the treatment effect. There were 162 students in the experimental group and 142 students in the control group. Both the experimental and control group students took the Achievement Test in Reproduction, Development, and Growth in Living Things (RDGLT), Science Process Skills Test, and Attitudes Toward Science Questionnaire, as pre-test and post-test. Repeated analysis of variance design was used in analyzing the data. Both the experimental and control group students were taught in RDGLT units for 22 class hours. The results indicated the positive effect of guided-inquiry approach on the Turkish students' cognitive as well as affective characteristics. The guided inquiry enhanced the experimental group students' understandings of the science concepts as well as the inquiry skills more than the control group students. Similarly, the experimental group students improved their attitudes toward science more than the control group students as a result of treatment. The guided inquiry seems a transition between traditional teaching method and student-centred activities in the Turkish schools.

  1. Longitudinal analysis of time, engagement, and achievement in at-risk versus non-risk students.

    PubMed

    Greenwood, C R

    1991-05-01

    This longitudinal study investigated the effects of time spent in academic instruction and time engaged on elementary students' academic achievement gains. Three groups were compared over grades as follows: (a) an at-risk experimental group of low-socioeconomic status (SES) students for whom teachers implemented classwide peer tutoring (CWPT) beginning with the second semester of first grade continuing through Grade 3; (b) an equivalent at-risk control group; and (c) a non-risk comparison group of students of average- to high-SES. In both the control and comparison groups, teachers employed conventional instructional practices over Grades 1 through 3. Results indicated significant group differences in the time spent in academic instruction, engagement, and gains on the subtests of the Metropolitan Achievement Test that favored the experimental and comparison groups over the control group. Implications include the effectiveness of CWPT for at-risk students and the continuing vulnerability of at-risk students whose daily instructional programs provide less instructional time and foster lower levels of active academic engagement.

  2. The CABRI fast neutron Hodoscope: Renovation, qualification program and first results following the experimental reactor restart

    NASA Astrophysics Data System (ADS)

    Chevalier, V.; Mirotta, S.; Guillot, J.; Biard, B.

    2018-01-01

    The CABRI experimental pulse reactor, located at the Cadarache nuclear research center, southern France, is devoted to the study of Reactivity Initiated Accidents (RIA). For the purpose of the CABRI International Program (CIP), managed and funded by IRSN, in the framework of an OECD/NEA agreement, a huge renovation of the facility has been conducted since 2003. The Cabri Water Loop was then installed to ensure prototypical Pressurized Water Reactor (PWR) conditions for testing irradiated fuel rods. The hodoscope installed in the CABRI reactor is a unique online fuel motion monitoring system, operated by IRSN and dedicated to the measurement of the fast neutrons emitted by the tested rod during the power pulse. It is one of the distinctive features of the CABRI reactor facility, which is operated by CEA. The system is able to determine the fuel motion, if any, with a time resolution of 1 ms and a spatial resolution of 3 mm. The hodoscope equipment has been upgraded as well during the CABRI facility renovation. This paper presents the main outcomes achieved with the hodoscope since October 2015, date of the first criticality of the CABRI reactor in its new Cabri Water Loop configuration. Results obtained during reactor commissioning phase functioning, either in steady-state mode (at low and high power, up to 23 MW) or in transient mode (start-up, possibly beyond 20 GW), are discussed.

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

    NASA Technical Reports Server (NTRS)

    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.

  4. A Professional Learning Community's Impact on Academic Achievement

    ERIC Educational Resources Information Center

    Ransom, Minnie

    2016-01-01

    English language learners (ELL students) were not attaining and maintaining sufficient proficiency at public schools in Northern California, as measured by students' achievement scores on state and district assessments. The purpose of this quasi-experimental research was to determine whether there were differences in academic language arts…

  5. Effectiveness of creative and productive instructional method towards students' learning achievement in steel structure course

    NASA Astrophysics Data System (ADS)

    Sugiyanto, Pribadi, Supriyanto, Bambang

    2017-09-01

    The purpose of this study was to investigate the effectiveness of Creative & Productive instructional method compared with conventional method. This research was a quasi-experimental study involving all Civil Engineering students at Universitas Negeri Malang who were taking a course of Steel Structure. The students were randomly assigned to two different treatment groups, 30 students in experimental group and 37 students in the control group. It was assumed that these groups were equal in all relevant aspects; they differed only in the treatment administered. We used the t-test to test the hypothesis. The results of this research suggest that: (l) the use of Creative & Productive instructional method can significantly improve students' learning achievement, (2) the use of Creative & Productive instructional method can significantly improve students' retention, (3) students' motivation has a significant effect on their learning achievement, and (4) students' motivation has a significant effect on their retention.

  6. Experimental study and simulation of 63Zn production via proton induce reaction.

    PubMed

    Rostampour, Malihe; Sadeghi, Mahdi; Aboudzadeh, Mohammadreza; Hamidi, Saeid; Soltani, Naser; Novin, Fatemeh Bolouri; Rahiminejad, Ali; Rajabifar, Saeid

    2018-06-01

    The 63 Zn was produced by16.8 MeV proton irradiation of natural copper. Thick target yield for 63 Zn in the energy range of 16.8 →12.2 MeV was 2.47 ± 0.12 GBq/μA.h. Reasonable agreement between achieved experimental data and theoretical value of thick target yield for 63 Zn was observed. A simple separation procedure of 63 Zn from copper target was developed using cation exchange chromatography. About 88 ± 5% of the loaded activity was recovered. The performance of FLUKA to reproduce experimental data of thick target yield of 63 Zn is validated. The achieved results from this code were compared with the corresponding experimental data. This comparison demonstrated that FLUKA provides a suitable tool for the simulation of radionuclide production using proton irradiation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. Acoustic analysis in Mudejar-Gothic churches: Experimental results

    NASA Astrophysics Data System (ADS)

    Galindo, Miguel; Zamarreño, Teófilo; Girón, Sara

    2005-05-01

    This paper describes the preliminary results of research work in acoustics, conducted in a set of 12 Mudejar-Gothic churches in the city of Seville in the south of Spain. Despite common architectural style, the churches feature individual characteristics and have volumes ranging from 3947 to 10 708 m3. Acoustic parameters were measured in unoccupied churches according to the ISO-3382 standard. An extensive experimental study was carried out using impulse response analysis through a maximum length sequence measurement system in each church. It covered aspects such as reverberation (reverberation times, early decay times), distribution of sound levels (sound strength); early to late sound energy parameters derived from the impulse responses (center time, clarity for speech, clarity, definition, lateral energy fraction), and speech intelligibility (rapid speech transmission index), which all take both spectral and spatial distribution into account. Background noise was also measured to obtain the NR indices. The study describes the acoustic field inside each temple and establishes a discussion for each one of the acoustic descriptors mentioned by using the theoretical models available and the principles of architectural acoustics. Analysis of the quality of the spaces for music and speech is carried out according to the most widespread criteria for auditoria. .

  8. Acoustic analysis in Mudejar-Gothic churches: experimental results.

    PubMed

    Galindo, Miguel; Zamarreño, Teófilo; Girón, Sara

    2005-05-01

    This paper describes the preliminary results of research work in acoustics, conducted in a set of 12 Mudejar-Gothic churches in the city of Seville in the south of Spain. Despite common architectural style, the churches feature individual characteristics and have volumes ranging from 3947 to 10 708 m3. Acoustic parameters were measured in unoccupied churches according to the ISO-3382 standard. An extensive experimental study was carried out using impulse response analysis through a maximum length sequence measurement system in each church. It covered aspects such as reverberation (reverberation times, early decay times), distribution of sound levels (sound strength); early to late sound energy parameters derived from the impulse responses (center time, clarity for speech, clarity, definition, lateral energy fraction), and speech intelligibility (rapid speech transmission index), which all take both spectral and spatial distribution into account. Background noise was also measured to obtain the NR indices. The study describes the acoustic field inside each temple and establishes a discussion for each one of the acoustic descriptors mentioned by using the theoretical models available and the principles of architectural acoustics. Analysis of the quality of the spaces for music and speech is carried out according to the most widespread criteria for auditoria.

  9. Usage of Computers and Calculators and Students' Achievement: Results from TIMSS 2003

    ERIC Educational Resources Information Center

    Antonijevic, Radovan

    2007-01-01

    The paper deals with the facts obtained from TIMSS 2003 (Trends in International Mathematics and Science Study). This international comparative study, which includes 47 participant countries worldwide, explores dependence between eighth grade students' achievement in the areas of mathematics, physics, chemistry, biology and geography, and basic…

  10. Predictors of cultural capital on science academic achievement at the 8th grade level

    NASA Astrophysics Data System (ADS)

    Misner, Johnathan Scott

    The purpose of the study was to determine if students' cultural capital is a significant predictor of 8th grade science achievement test scores in urban locales. Cultural capital refers to the knowledge used and gained by the dominant class, which allows social and economic mobility. Cultural capital variables include magazines at home and parental education level. Other variables analyzed include socioeconomic status (SES), gender, and English language learners (ELL). This non-experimental study analyzed the results of the 2011 Eighth Grade Science National Assessment of Educational Progress (NAEP). The researcher analyzed the data using a multivariate stepwise regression analysis. The researcher concluded that the addition of cultural capital factors significantly increased the predictive power of the model where magazines in home, gender, student classified as ELL, parental education level, and SES were the independent variables and science achievement was the dependent variable. For alpha=0.05, the overall test for the model produced a R2 value of 0.232; therefore the model predicted 23.2% of variance in science achievement results. Other major findings include: higher measures of home resources predicted higher 2011 NAEP eighth grade science achievement; males were predicted to have higher 2011 NAEP 8 th grade science achievement; classified ELL students were predicted to score lower on the NAEP eight grade science achievement; higher parent education predicted higher NAEP eighth grade science achievement; lower measures of SES predicted lower 2011 NAEP eighth grade science achievement. This study contributed to the research in this field by identifying cultural capital factors that have been found to have statistical significance on predicting eighth grade science achievement results, which can lead to strategies to help improve science academic achievement among underserved populations.

  11. Effect of Digital Game Based Learning on Ninth Grade Students' Mathematics Achievement

    ERIC Educational Resources Information Center

    Swearingen, Dixie K.

    2011-01-01

    This experimental study examined the effect of an educational massive multiplayer online game (MMOG) on achievement on a standards-based mathematics exam. It also examined the interaction of student characteristics (gender and socioeconomic status) with digital game play on mathematics achievement. Two hundred eighty ninth grade students from a…

  12. Minnesota Developmental Achievement Centers: 1987 Survey Results. Policy Analysis Series, No. 28.

    ERIC Educational Resources Information Center

    Minnesota Governor's Planning Council on Developmental Disabilities, St. Paul.

    This paper presents data collected from rehabilitation centers serving individuals with developmental disabilities in Minnesota, called Developmental Achievement Centers (DACs). The data focus on finances, programs, and clients, and are compared with data from previous years. All 97 providers of adult services in Minnesota completed the survey,…

  13. Achieving across-laboratory replicability in psychophysical scaling

    PubMed Central

    Ward, Lawrence M.; Baumann, Michael; Moffat, Graeme; Roberts, Larry E.; Mori, Shuji; Rutledge-Taylor, Matthew; West, Robert L.

    2015-01-01

    It is well known that, although psychophysical scaling produces good qualitative agreement between experiments, precise quantitative agreement between experimental results, such as that routinely achieved in physics or biology, is rarely or never attained. A particularly galling example of this is the fact that power function exponents for the same psychological continuum, measured in different laboratories but ostensibly using the same scaling method, magnitude estimation, can vary by a factor of three. Constrained scaling (CS), in which observers first learn a standardized meaning for a set of numerical responses relative to a standard sensory continuum and then make magnitude judgments of other sensations using the learned response scale, has produced excellent quantitative agreement between individual observers’ psychophysical functions. Theoretically it could do the same for across-laboratory comparisons, although this needs to be tested directly. We compared nine different experiments from four different laboratories as an example of the level of across experiment and across-laboratory agreement achievable using CS. In general, we found across experiment and across-laboratory agreement using CS to be significantly superior to that typically obtained with conventional magnitude estimation techniques, although some of its potential remains to be realized. PMID:26191019

  14. Achievements and challenges in structural bioinformatics and computational biophysics.

    PubMed

    Samish, Ilan; Bourne, Philip E; Najmanovich, Rafael J

    2015-01-01

    The field of structural bioinformatics and computational biophysics has undergone a revolution in the last 10 years. Developments that are captured annually through the 3DSIG meeting, upon which this article reflects. An increase in the accessible data, computational resources and methodology has resulted in an increase in the size and resolution of studied systems and the complexity of the questions amenable to research. Concomitantly, the parameterization and efficiency of the methods have markedly improved along with their cross-validation with other computational and experimental results. The field exhibits an ever-increasing integration with biochemistry, biophysics and other disciplines. In this article, we discuss recent achievements along with current challenges within the field. © The Author 2014. Published by Oxford University Press.

  15. Developing Seventh Grade Students' Understanding of Complex Environmental Problems with Systems Tools and Representations: a Quasi-experimental Study

    NASA Astrophysics Data System (ADS)

    Doganca Kucuk, Zerrin; Saysel, Ali Kerem

    2017-03-01

    A systems-based classroom intervention on environmental education was designed for seventh grade students; the results were evaluated to see its impact on the development of systems thinking skills and standard science achievement and whether the systems approach is a more effective way to teach environmental issues that are dynamic and complex. A quasi-experimental methodology was used to compare performances of the participants in various dimensions, including systems thinking skills, competence in dynamic environmental problem solving and success in science achievement tests. The same pre-, post- and delayed tests were used with both the comparison and experimental groups in the same public middle school in Istanbul. Classroom activities designed for the comparison group (N = 20) followed the directives of the Science and Technology Curriculum, while the experimental group (N = 22) covered the same subject matter through activities benefiting from systems tools and representations such as behaviour over time graphs, causal loop diagrams, stock-flow structures and hands-on dynamic modelling. After a one-month systems-based instruction, the experimental group demonstrated significantly better systems thinking and dynamic environmental problem solving skills. Achievement in dynamic problem solving was found to be relatively stable over time. However, standard science achievement did not improve at all. This paper focuses on the quantitative analysis of the results, the weaknesses of the curriculum and educational implications.

  16. Automated detection of discourse segment and experimental types from the text of cancer pathway results sections.

    PubMed

    Burns, Gully A P C; Dasigi, Pradeep; de Waard, Anita; Hovy, Eduard H

    2016-01-01

    Automated machine-reading biocuration systems typically use sentence-by-sentence information extraction to construct meaning representations for use by curators. This does not directly reflect the typical discourse structure used by scientists to construct an argument from the experimental data available within a article, and is therefore less likely to correspond to representations typically used in biomedical informatics systems (let alone to the mental models that scientists have). In this study, we develop Natural Language Processing methods to locate, extract, and classify the individual passages of text from articles' Results sections that refer to experimental data. In our domain of interest (molecular biology studies of cancer signal transduction pathways), individual articles may contain as many as 30 small-scale individual experiments describing a variety of findings, upon which authors base their overall research conclusions. Our system automatically classifies discourse segments in these texts into seven categories (fact, hypothesis, problem, goal, method, result, implication) with an F-score of 0.68. These segments describe the essential building blocks of scientific discourse to (i) provide context for each experiment, (ii) report experimental details and (iii) explain the data's meaning in context. We evaluate our system on text passages from articles that were curated in molecular biology databases (the Pathway Logic Datum repository, the Molecular Interaction MINT and INTACT databases) linking individual experiments in articles to the type of assay used (coprecipitation, phosphorylation, translocation etc.). We use supervised machine learning techniques on text passages containing unambiguous references to experiments to obtain baseline F1 scores of 0.59 for MINT, 0.71 for INTACT and 0.63 for Pathway Logic. Although preliminary, these results support the notion that targeting information extraction methods to experimental results could provide

  17. Beta decay and the origins of biological chirality - Experimental results

    NASA Technical Reports Server (NTRS)

    Gidley, D. W.; Rich, A.; Van House, J.; Zitzewitz, P. W.

    1982-01-01

    Preliminary experimental results are presented of an investigation of the possible role of preferential radiolysis by electrons emitted in the beta decay of radionuclides, a parity-nonconserving process, in the universal causation of the optical activity of biological compounds. Experiments were designed to measure the asymmetry in the production of triplet positronium upon the bombardment of an amino acid powder target by a collimated beam of positrons as positron helicity or target chirality is reversed. No asymmetry down to a level of 0.0007 is found in experiments on the D and L forms of cystine and tryptophan, indicating an asymmetry in positronium formation cross section of less than 0.01, while an asymmetry of 0.0031 is found for leucine, corresponding to a formation cross section asymmetry of about 0.04

  18. Solving and Learning Soft Temporal Constraints: Experimental Setting and Results

    NASA Technical Reports Server (NTRS)

    Rossi, F.; Sperduti, A.; Venable, K. B.; Khatib, L.; Morris, P.; Morris, R.; Clancy, Daniel (Technical Monitor)

    2002-01-01

    Soft temporal constraints problems allow to describe in a natural way scenarios where events happen over time and preferences are associated to event distances and durations. However, sometimes such local preferences are difficult to set, and it may be easier instead to associate preferences to some complete solutions of the problem. Machine learning techniques can be useful in this respect. In this paper we describe two solvers (one more general and the other one more efficient) for tractable subclasses of soft temporal problems, and we show some experimental results. The random generator used to build the problems on which tests are performed is also described. We also compare the two solvers highlighting the tradeoff between performance and representational power. Finally, we present a learning module and we show its behavior on randomly-generated examples.

  19. Transient Lift-Off Test Results for an Experimental Hybrid Bearing in Air

    DTIC Science & Technology

    2009-12-01

    High-Speed Hydrostatic Bearings,” ASME Journal of Tribology, Vol. 116, n2, 1994, pp. 337-344. [2] Scharrer, J.K., Tellier , J. and Hibbs, R., “A...J.K., Tellier , J. and Hibbs, R., “A Study of the Transient Performance of Hydrostatic Journal Bearings: Part II-Experimental Results,” STLE Paper 91...TC- 3B-2, 1991. [4] Sharrer, J., Tellier , J. and Hibbs, R., “Start Transient Testing of an Annular Hydrostatic Bearing in Liquid Oxygen,” AIAA

  20. The impact of crowd noise on officiating in muay thai: achieving external validity in an experimental setting.

    PubMed

    Myers, Tony; Balmer, Nigel

    2012-01-01

    Numerous factors have been proposed to explain the home advantage in sport. Several authors have suggested that a partisan home crowd enhances home advantage and that this is at least in part a consequence of their influence on officiating. However, while experimental studies examining this phenomenon have high levels of internal validity (since only the "crowd noise" intervention is allowed to vary), they suffer from a lack of external validity, with decision-making in a laboratory setting typically bearing little resemblance to decision-making in live sports settings. Conversely, observational and quasi-experimental studies with high levels of external validity suffer from low levels of internal validity as countless factors besides crowd noise vary. The present study provides a unique opportunity to address these criticisms, by conducting a controlled experiment on the impact of crowd noise on officiating in a live tournament setting. Seventeen qualified judges officiated on thirty Thai boxing bouts in a live international tournament setting featuring "home" and "away" boxers. In each bout, judges were randomized into a "noise" (live sound) or "no crowd noise" (noise-canceling headphones and white noise) condition, resulting in 59 judgments in the "no crowd noise" and 61 in the "crowd noise" condition. The results provide the first experimental evidence of the impact of live crowd noise on officials in sport. A cross-classified statistical model indicated that crowd noise had a statistically significant impact, equating to just over half a point per bout (in the context of five round bouts with the "10-point must" scoring system shared with professional boxing). The practical significance of the findings, their implications for officiating and for the future conduct of crowd noise studies are discussed.

  1. The Impact of Crowd Noise on Officiating in Muay Thai: Achieving External Validity in an Experimental Setting

    PubMed Central

    Myers, Tony; Balmer, Nigel

    2012-01-01

    Numerous factors have been proposed to explain the home advantage in sport. Several authors have suggested that a partisan home crowd enhances home advantage and that this is at least in part a consequence of their influence on officiating. However, while experimental studies examining this phenomenon have high levels of internal validity (since only the “crowd noise” intervention is allowed to vary), they suffer from a lack of external validity, with decision-making in a laboratory setting typically bearing little resemblance to decision-making in live sports settings. Conversely, observational and quasi-experimental studies with high levels of external validity suffer from low levels of internal validity as countless factors besides crowd noise vary. The present study provides a unique opportunity to address these criticisms, by conducting a controlled experiment on the impact of crowd noise on officiating in a live tournament setting. Seventeen qualified judges officiated on thirty Thai boxing bouts in a live international tournament setting featuring “home” and “away” boxers. In each bout, judges were randomized into a “noise” (live sound) or “no crowd noise” (noise-canceling headphones and white noise) condition, resulting in 59 judgments in the “no crowd noise” and 61 in the “crowd noise” condition. The results provide the first experimental evidence of the impact of live crowd noise on officials in sport. A cross-classified statistical model indicated that crowd noise had a statistically significant impact, equating to just over half a point per bout (in the context of five round bouts with the “10-point must” scoring system shared with professional boxing). The practical significance of the findings, their implications for officiating and for the future conduct of crowd noise studies are discussed. PMID:23049520

  2. Learning Model and Form of Assesment toward the Inferensial Statistical Achievement by Controlling Numeric Thinking Skills

    ERIC Educational Resources Information Center

    Widiana, I. Wayan; Jampel, I. Nyoman

    2016-01-01

    This study aimed to find out the effect of learning model and form of assessment toward inferential statistical achievement after controlling numeric thinking skills. This study was quasi experimental study with 130 students as the sample. The data analysis used ANCOVA. After controlling numeric thinking skills, the result of this study show that:…

  3. Effects of Improvements in Interval Timing on the Mathematics Achievement of Elementary School Students

    ERIC Educational Resources Information Center

    Taub, Gordon E.; McGrew, Kevin S.; Keith, Timothy Z.

    2015-01-01

    This article examines the effect of improvements in timing/rhythmicity on mathematics achievement. A total of 86 participants attending 1st through 4th grades completed pre- and posttest measures of mathematics achievement from the Woodcock-Johnson III Tests of Achievement. Students in the experimental group participated in a 4-week intervention…

  4. Incremental Validity of Thinking Styles in Predicting Academic Achievements: An Experimental Study in Hypermedia Learning Environments

    ERIC Educational Resources Information Center

    Fan, Weiqiao; Zhang, Li-Fang; Watkins, David

    2010-01-01

    The study examined the incremental validity of thinking styles in predicting academic achievement after controlling for personality and achievement motivation in the hypermedia-based learning environment. Seventy-two Chinese college students from Shanghai, the People's Republic of China, took part in this instructional experiment. The…

  5. Direct Numerical Simulation of Liquid Nozzle Spray with Comparison to Shadowgraphy and X-Ray Computed Tomography Experimental Results

    NASA Astrophysics Data System (ADS)

    van Poppel, Bret; Owkes, Mark; Nelson, Thomas; Lee, Zachary; Sowell, Tyler; Benson, Michael; Vasquez Guzman, Pablo; Fahrig, Rebecca; Eaton, John; Kurman, Matthew; Kweon, Chol-Bum; Bravo, Luis

    2014-11-01

    In this work, we present high-fidelity Computational Fluid Dynamics (CFD) results of liquid fuel injection from a pressure-swirl atomizer and compare the simulations to experimental results obtained using both shadowgraphy and phase-averaged X-ray computed tomography (CT) scans. The CFD and experimental results focus on the dense near-nozzle region to identify the dominant mechanisms of breakup during primary atomization. Simulations are performed using the NGA code of Desjardins et al (JCP 227 (2008)) and employ the volume of fluid (VOF) method proposed by Owkes and Desjardins (JCP 270 (2013)), a second order accurate, un-split, conservative, three-dimensional VOF scheme providing second order density fluxes and capable of robust and accurate high density ratio simulations. Qualitative features and quantitative statistics are assessed and compared for the simulation and experimental results, including the onset of atomization, spray cone angle, and drop size and distribution.

  6. The Effect of Preschool Education on Math Achievement.

    ERIC Educational Resources Information Center

    Vondrak, Maripatricia

    A study examined the effects of preschool attendance on third graders' mathematics achievement. The subjects for the study were randomly selected from 111 third graders from a predominantly low socioeconomic neighborhood in Chicago. All students were from minority groups. The experimental group was comprised of 21 students who had attended…

  7. Effectiveness of Constructivist Approach on Academic Achievement in Science at Secondary Level

    ERIC Educational Resources Information Center

    Adak, Samaresh

    2017-01-01

    The present study investigated the effectiveness of constructivist approach on academic achievement in science at secondary level using pre-test, post-test, experimental and control group design, with 58 samples grouped as experimental group (29) and control group (29) on the basis of matching by intelligence test. The investigators conducted this…

  8. Growing minds: The effect of school gardening programs on the science achievement of elementary students

    NASA Astrophysics Data System (ADS)

    Klemmer, Cynthia Davis

    Science literacy refers to a basic knowledge and understanding of science concepts and processes needed to consider issues and make choices on a daily basis in an increasingly technology-driven society. A critical precursor to producing science literate adults is actively involving children in science while they are young. National and state (TX) science standards advocate the use of constructivist methods including hands-on, experiential activities that foster the development of science process skills through real-world investigations. School gardens show promise as a tool for implementing these guidelines by providing living laboratories for active science. Gardens offer opportunities for a variety of hands-on investigations, enabling students to apply and practice science skills. School gardens are increasing in popularity; however, little research data exists attesting to their actual effectiveness in enhancing students' science achievement. The study used a quasi-experimental posttest-only research design to assess the effects of a school gardening program on the science achievement of 3rd, 4th, and 5th grade elementary students. The sample consisted of 647 students from seven elementary schools in Temple, Texas. The experimental group participated in school gardening activities as part of their science curriculum. The control group did not garden and were taught using traditional classroom-based methods. Results showed higher scores for students in the experimental group which were statistically significant. Post-hoc tests using Scheffe's method revealed that these differences were attributed to the 5th grade. No statistical significance was found between girls and boys in the experimental group, indicating that gardening was equally effective for both genders. Within each gender, statistical significance was found between males in the experimental and control groups at all three grade levels, and for females in the 5 th grade. This research indicated that

  9. Confidence in Science and Achievement Outcomes of Fourth-Grade Students in Korea: Results from the TIMSS 2011 Assessment

    ERIC Educational Resources Information Center

    House, J. Daniel; Telese, James A.

    2017-01-01

    Findings from assessments of fourth-grade science have indicated that students in Korea scored higher than international averages. Research results have also shown that attitudes toward science were related to achievement outcomes for Korean students. The purpose of this study was to examine the relationship between confidence in science and…

  10. Numerical simulation of granular flows : comparison with experimental results

    NASA Astrophysics Data System (ADS)

    Pirulli, M.; Mangeney-Castelnau, A.; Lajeunesse, E.; Vilotte, J.-P.; Bouchut, F.; Bristeau, M. O.; Perthame, B.

    2003-04-01

    Granular avalanches such as rock or debris flows regularly cause large amounts of human and material damages. Numerical simulation of granular avalanches should provide a useful tool for investigating, within realistic geological contexts, the dynamics of these flows and of their arrest phase and for improving the risk assessment of such natural hazards. Validation of debris avalanche numerical model on granular experiments over inclined plane is performed here. The comparison is performed by simulating granular flow of glass beads from a reservoir through a gate down an inclined plane. This unsteady situation evolves toward the steady state observed in the laboratory. Furthermore simulation exactly reproduces the arrest phase obtained by suddenly closing the gate of the reservoir once a thick flow has developped. The spreading of a granular mass released from rest at the top of a rough inclined plane is also investigated. The evolution of the avalanche shape, the velocity and the characteristics of the arrest phase are compared with experimental results and analysis of the involved forces are studied for various flow laws.

  11. Cyclic Inelastic Deformation and Fatigue Resistance of a Rail Steel : Experimental Results and Mathematical Models

    DOT National Transportation Integrated Search

    1981-10-01

    Experimental results developed from tests of uniaxial, smooth specimens obtained from the head of an unused section of rail have been reported. Testing encompassed a broad range of conditions - monotonic tension, monotonic compression, and fully reve...

  12. Initial development of the two-dimensional ejector shear layer - Experimental results

    NASA Technical Reports Server (NTRS)

    Benjamin, M. A.; Dufflocq, M.; Roan, V. P.

    1993-01-01

    An experimental investigation designed to study the development of shear layers in a two-dimensional single-nozzle ejector has been completed. In this study, combinations of air/air, argon/air, helium/air, and air/helium were used as the supersonic primary and subsonic secondary, respectively. Mixing of the gases occurred in a constant-area tube 39.1 mm high by 25.4 mm wide, where the inlet static pressure was maintained at 35 kPa. The cases studied resulted in convective Mach numbers between 0.058 and 1.64, density ratios between 0.102 and 3.49, and velocity ratios between 0.065 and 0.811. The resulting data shows the differences in the shear-layer development for the various combinations of independent variables utilized in the investigation. The normalized growth-rates in the near-field were found to be similar to two-dimensional mixing layers. These results have enhanced the ability to analyze and design ejector systems as well as providing a better understanding of the physics.

  13. Object impedance control for cooperative manipulation - Theory and experimental results

    NASA Technical Reports Server (NTRS)

    Schneider, Stanley A.; Cannon, Robert H., Jr.

    1992-01-01

    This paper presents the dynamic control module of the Dynamic and Strategic Control of Cooperating Manipulators (DASCCOM) project at Stanford University's Aerospace Robotics Laboratory. First, the cooperative manipulation problem is analyzed from a systems perspective, and the desirable features of a control system for cooperative manipulation are discussed. Next, a control policy is developed that enforces a controlled impedance not of the individual arm endpoints, but of the manipulated object itself. A parallel implementation for a multiprocessor system is presented. The controller fully compensates for the system dynamics and directly controls the object internal forces. Most importantly, it presents a simple, powerful, intuitive interface to higher level strategic control modules. Experimental results from a dual two-link-arm robotic system are used to compare the object impedance controller with other strategies, both for free-motion slews and environmental contact.

  14. Laser long-range remote-sensing program experimental results

    NASA Astrophysics Data System (ADS)

    Highland, Ronald G.; Shilko, Michael L.; Fox, Marsha J.; Gonglewski, John D.; Czyzak, Stanley R.; Dowling, James A.; Kelly, Brian; Pierrottet, Diego F.; Ruffatto, Donald; Loando, Sharon; Matsuura, Chris; Senft, Daniel C.; Finkner, Lyle; Rae, Joe; Gallegos, Joe

    1995-12-01

    A laser long range remote sensing (LRS) program is being conducted by the United States Air Force Phillips Laboratory (AF/PL). As part of this program, AF/PL is testing the feasibility of developing a long path CO(subscript 2) laser-based DIAL system for remote sensing. In support of this program, the AF/PL has recently completed an experimental series using a 21 km slant- range path (3.05 km ASL transceiver height to 0.067 km ASL target height) at its Phillips Laboratory Air Force Maui Optical Station (AMOS) facility located on Maui, Hawaii. The dial system uses a 3-joule, (superscript 13)C isotope laser coupled into a 0.6 m diameter telescope. The atmospheric optical characterization incorporates information from an infrared scintillometer co-aligned to the laser path, atmospheric profiles from weather balloons launched from the target site, and meteorological data from ground stations at AMOS and the target site. In this paper, we report a description of the experiment configuration, a summary of the results, a summary of the atmospheric conditions and their implications to the LRS program. The capability of such a system for long-range, low-angle, slant-path remote sensing is discussed. System performance issues relating to both coherent and incoherent detection methods, atmospheric limitations, as well as, the development of advanced models to predict performance of long range scenarios are presented.

  15. [Relationship between the prone position and achieving head control at 3 months].

    PubMed

    Pérez-Machado, J L; Rodríguez-Fuentes, G

    2013-10-01

    Owing to the significant increase of mild motor delays and the strong intolerance of infants to be placed on prone position observed in the Physiotherapy Unit of the Maternal and Children's University Hospital of the Canaries (HUMIC), a study was conducted to determine whether positioning infants in the prone position while awake affected the achievement and quality of head control at three months. A prospective comparative practice-based study of a representative sample of 67 healthy infants born in the HUMIC, and divided into an experimental group (n = 35) and control group (n = 32). The Alberta Infant Motor Scale (AIMS) and a parent questionnaire were used as measurement tools. The intervention consisted of regular home visits to the experimental group (from the first to the third month). The two groups were evaluated in their homes at the end of 3 months. The differences in mean raw score of the AIMS at 3 months were, 16.26 in the experimental group and 10.38 in control group (P<.001). The percentile mean was 94 in the experimental group, and less than 50 (42) in the control group. All of the experimental group babies achieved the head control, with only 8 in the control group (25%). The significant findings suggest a direct relationship between the time spent in the prone position when the baby is awake and the achievement of head control at three months. Copyright © 2012 Asociación Española de Pediatría. Published by Elsevier Espana. All rights reserved.

  16. Results of Experimental Study on Flexitime and Family Life.

    ERIC Educational Resources Information Center

    Winett, Richard A.; Neale, Michael S.

    1980-01-01

    According to two small experimental studies of flexible working hours, federal workers with young children choose to arrive at and depart from work earlier, allowing them to increase the time spent with their families and to engage in recreational, educational, and household activities. (Author/SK)

  17. Overview of recent experimental results from the Aditya tokamak

    NASA Astrophysics Data System (ADS)

    Tanna, R. L.; Ghosh, J.; Chattopadhyay, P. K.; Raj, Harshita; Patel, Sharvil; Dhyani, P.; Gupta, C. N.; Jadeja, K. A.; Patel, K. M.; Bhatt, S. B.; Panchal, V. K.; Patel, N. C.; Chavda, Chhaya; Praveenlal, E. V.; Shah, K. S.; Makawana, M. N.; Jha, S. K.; Gopalkrishana, M. V.; Tahiliani, K.; Sangwan, Deepak; Raju, D.; Nagora, Umesh; Pathak, S. K.; Atrey, P. K.; Purohit, S.; Raval, J.; Joisa, Y. S.; Rao, C. V. S.; Chowdhuri, M. B.; Banerjee, S.; Ramaiya, N.; Manchanda, R.; Thomas, J.; Kumar, Ajai; Ajay, Kumar; Sharma, P. K.; Kulkarni, S. V.; Sathyanarayana, K.; Shukla, B. K.; Das, Amita; Jha, R.; Saxena, Y. C.; Sen, A.; Kaw, P. K.; Bora, D.; the ADITYA Team

    2017-10-01

    Several experiments, related to controlled thermonuclear fusion research and highly relevant for large size tokamaks, including ITER, have been carried out in ADITYA, an ohmically heated circular limiter tokamak. Repeatable plasma discharges of a maximum plasma current of ~160 kA and discharge duration beyond ~250 ms with a plasma current flattop duration of ~140 ms have been obtained for the first time in ADITYA. The reproducibility of the discharge reproducibility has been improved considerably with lithium wall conditioning, and improved plasma discharges are obtained by precisely controlling the position of the plasma. In these discharges, chord-averaged electron density ~3.0-4.0  ×  1019 m-3 using multiple hydrogen gas puffs, with a temperature of the order of ~500-700 eV, have been achieved. Novel experiments related to disruption control are carried out and disruptions, induced by hydrogen gas puffing, are successfully mitigated using the biased electrode and ion cyclotron resonance pulse techniques. Runaway electrons are successfully mitigated by applying a short local vertical field (LVF) pulse. A thorough disruption database has been generated by identifying the different categories of disruption. Detailed analysis of several hundred disrupted discharges showed that the current quench time is inversely proportional to the q edge. Apart from this, for volt-sec recovery during the plasma formation phase, low loop voltage start-up and current ramp-up experiments have been carried out using electron cyclotron resonance heating (ECRH). Successful recovery of volt-sec leads to the achievement of longer plasma discharge durations. In addition, the neon gas puff assisted radiative improved confinement mode has also been achieved in ADITYA. All of the above mentioned experiments will be discussed in this paper.

  18. VX Hydrolysis by Human Serum Paraoxonase 1: A Comparison of Experimental and Computational Results

    PubMed Central

    Peterson, Matthew W.; Fairchild, Steven Z.; Otto, Tamara C.; Mohtashemi, Mojdeh; Cerasoli, Douglas M.; Chang, Wenling E.

    2011-01-01

    Human Serum paraoxonase 1 (HuPON1) is an enzyme that has been shown to hydrolyze a variety of chemicals including the nerve agent VX. While wildtype HuPON1 does not exhibit sufficient activity against VX to be used as an in vivo countermeasure, it has been suggested that increasing HuPON1's organophosphorous hydrolase activity by one or two orders of magnitude would make the enzyme suitable for this purpose. The binding interaction between HuPON1 and VX has recently been modeled, but the mechanism for VX hydrolysis is still unknown. In this study, we created a transition state model for VX hydrolysis (VXts) in water using quantum mechanical/molecular mechanical simulations, and docked the transition state model to 22 experimentally characterized HuPON1 variants using AutoDock Vina. The HuPON1-VXts complexes were grouped by reaction mechanism using a novel clustering procedure. The average Vina interaction energies for different clusters were compared to the experimentally determined activities of HuPON1 variants to determine which computational procedures best predict how well HuPON1 variants will hydrolyze VX. The analysis showed that only conformations which have the attacking hydroxyl group of VXts coordinated by the sidechain oxygen of D269 have a significant correlation with experimental results. The results from this study can be used for further characterization of how HuPON1 hydrolyzes VX and design of HuPON1 variants with increased activity against VX. PMID:21655255

  19. The Effect of Peer Support on University Level Students' English Language Achievements

    ERIC Educational Resources Information Center

    Sari, Irfan; Çeliköz, Nadir; Ünal, Süleyman

    2017-01-01

    The purpose of the study is to investigate the effect of peer support on university level students' English language achievements. An experimental model with pretest-posttest experimental and control group was used with 800 students who were studying at a university in Istanbul vicinity. As experiment group, 400 students (200 of whom…

  20. The K-12 Service-Learning Standards and Fourth Grade Students' Math Achievement: A Quasi-Experimental Study in Georgia

    ERIC Educational Resources Information Center

    Clark, Tanner

    2017-01-01

    The underachievement of students in the US is a growing and significant problem. When guided by the K-12 Service-Learning Standards for Quality Practice, research has shown service-learning results in increased academic achievement among middle and high school students. This study focused on identifying the impact of service learning interventions…

  1. Mathematics beliefs and achievement of adolescent students in Japan: results from the TIMSS 1999 assessment.

    PubMed

    House, J Daniel

    2005-12-01

    A recent study (1) of undergraduate students in a precalculus course indicated that they expressed slightly positive attitudes toward mathematics. It is important, however, to examine relationships between students' initial attitudes and achievement outcomes. The present purpose was to assess the relationship between self-beliefs and mathematics achievement for a large national sample of students from the TIMSS 1999 international sample (eighth graders) from Japan. Several significant relationships between mathematics beliefs and test scores were noted. In addition, the overall multiple regression equation that assessed the joint significance of the complete set of self-belief variables was significant (F7.65 = 159.48, p < .001) and explained 20.6% of the variance in mathematics achievement test scores.

  2. Aberration correction results in the IBM STEM instrument.

    PubMed

    Batson, P E

    2003-09-01

    Results from the installation of aberration correction in the IBM 120 kV STEM argue that a sub-angstrom probe size has been achieved. Results and the experimental methods used to obtain them are described here. Some post-experiment processing is necessary to demonstrate the probe size of about 0.078 nm. While the promise of aberration correction is demonstrated, we remain at the very threshold of practicality, given the very stringent stability requirements.

  3. Manufacturing of glassy thin shell for adaptive optics: results achieved

    NASA Astrophysics Data System (ADS)

    Poutriquet, F.; Rinchet, A.; Carel, J.-L.; Leplan, H.; Ruch, E.; Geyl, R.; Marque, G.

    2012-07-01

    Glassy thin shells are key components for the development of adaptive optics and are part of future & innovative projects such as ELT. However, manufacturing thin shells is a real challenge. Even though optical requirements for the front face - or optical face - are relaxed compared to conventional passive mirrors, requirements concerning thickness uniformity are difficult to achieve. In addition, process has to be completely re-defined as thin mirror generates new manufacturing issues. In particular, scratches and digs requirement is more difficult as this could weaken the shell, handling is also an important issue due to the fragility of the mirror. Sagem, through REOSC program, has recently manufactured different types of thin shells in the frame of European projects: E-ELT M4 prototypes and VLT Deformable Secondary Mirror (VLT DSM).

  4. The Impact of Internet Virtual Physics Laboratory Instruction on the Achievement in Physics, Science Process Skills and Computer Attitudes of 10th-Grade Students

    NASA Astrophysics Data System (ADS)

    Yang, Kun-Yuan; Heh, Jia-Sheng

    2007-10-01

    The purpose of this study was to investigate and compare the impact of Internet Virtual Physics Laboratory (IVPL) instruction with traditional laboratory instruction in physics academic achievement, performance of science process skills, and computer attitudes of tenth grade students. One-hundred and fifty students from four classes at one private senior high school in Taoyuan Country, Taiwan, R.O.C. were sampled. All four classes contained 75 students who were equally divided into an experimental group and a control group. The pre-test results indicated that the students' entry-level physics academic achievement, science process skills, and computer attitudes were equal for both groups. On the post-test, the experimental group achieved significantly higher mean scores in physics academic achievement and science process skills. There was no significant difference in computer attitudes between the groups. We concluded that the IVPL had potential to help tenth graders improve their physics academic achievement and science process skills.

  5. Reflectivity of 1D photonic crystals: A comparison of computational schemes with experimental results

    NASA Astrophysics Data System (ADS)

    Pérez-Huerta, J. S.; Ariza-Flores, D.; Castro-García, R.; Mochán, W. L.; Ortiz, G. P.; Agarwal, V.

    2018-04-01

    We report the reflectivity of one-dimensional finite and semi-infinite photonic crystals, computed through the coupling to Bloch modes (BM) and through a transfer matrix method (TMM), and their comparison to the experimental spectral line shapes of porous silicon (PS) multilayer structures. Both methods reproduce a forbidden photonic bandgap (PBG), but slowly-converging oscillations are observed in the TMM as the number of layers increases to infinity, while a smooth converged behavior is presented with BM. The experimental reflectivity spectra is in good agreement with the TMM results for multilayer structures with a small number of periods. However, for structures with large amount of periods, the measured spectral line shapes exhibit better agreement with the smooth behavior predicted by BM.

  6. Experimental and computational flow-field results for an all-body hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Cleary, Joseph W.

    1989-01-01

    A comprehensive test program is defined which is being implemented in the NASA/Ames 3.5 foot Hypersonic Wind Tunnel for obtaining data on a generic all-body hypersonic vehicle for computational fluid dynamics (CFD) code validation. Computational methods (approximate inviscid methods and an upwind parabolized Navier-Stokes code) currently being applied to the all-body model are outlined. Experimental and computational results on surface pressure distributions and Pitot-pressure surveys for the basic sharp-nose model (without control surfaces) at a free-stream Mach number of 7 are presented.

  7. Experimental light scattering by small particles: first results with a novel Mueller matrix scatterometer

    NASA Astrophysics Data System (ADS)

    Penttilä, Antti; Maconi, Göran; Kassamakov, Ivan; Gritsevich, Maria; Helander, Petteri; Puranen, Tuomas; Hæggström, Edward; Muinonen, Karri

    2017-06-01

    We describe a setup for measuring the full angular Mueller matrix profile of a single mm- to μm-sized sample, and verify the experimental results against a theoretical model. The scatterometer has a fixed or levitating sample, illuminated with a laser beam whose full polarization state is controlled. The scattered light is detected with a combination of wave retarder, linear polarizer, and photomultiplier tube that is attached to a rotational stage. The first results are reported.

  8. Experimental and Numerical Modeling of Fluid Flow Processes in Continuous Casting: Results from the LIMMCAST-Project

    NASA Astrophysics Data System (ADS)

    Timmel, K.; Kratzsch, C.; Asad, A.; Schurmann, D.; Schwarze, R.; Eckert, S.

    2017-07-01

    The present paper reports about numerical simulations and model experiments concerned with the fluid flow in the continuous casting process of steel. This work was carried out in the LIMMCAST project in the framework of the Helmholtz alliance LIMTECH. A brief description of the LIMMCAST facilities used for the experimental modeling at HZDR is given here. Ultrasonic and inductive techniques and the X-ray radioscopy were employed for flow measurements or visualizations of two-phase flow regimes occurring in the submerged entry nozzle and the mold. Corresponding numerical simulations were performed at TUBAF taking into account the dimensions and properties of the model experiments. Numerical models were successfully validated using the experimental data base. The reasonable and in many cases excellent agreement of numerical with experimental data allows to extrapolate the models to real casting configurations. Exemplary results will be presented here showing the effect of electromagnetic brakes or electromagnetic stirrers on the flow in the mold or illustrating the properties of two-phase flows resulting from an Ar injection through the stopper rod.

  9. RFI in hybrid loops - Simulation and experimental results.

    NASA Technical Reports Server (NTRS)

    Ziemer, R. E.; Nelson, D. R.; Raghavan, H. R.

    1972-01-01

    A digital simulation of an imperfect second-order hybrid phase-locked loop (HPLL) operating in radio frequency interference (RFI) is described. Its performance is characterized in terms of phase error variance and phase error probability density function (PDF). Monte-Carlo simulation is used to show that the HPLL can be superior to the conventional phase-locked loops in RFI backgrounds when minimum phase error variance is the goodness criterion. Similar experimentally obtained data are given in support of the simulation data.

  10. The Effect of Social and Token Economy Reinforcements on Academic Achievement of Students with Intellectual Disabilities

    PubMed Central

    Ashoori, Mohammad; Sereshki, Narges Adib

    2011-01-01

    Objective This study investigates the effect of social and token economy reinforcements on academic achievement of 9th grade boy students with intellectual disabilities in an experimental science class in Tehran Province. Method The method used for this study was experimental by pre-test, post- test with a control group. The boy students with intellectual disabilities from three junior high schools participated in this study. The sample consisted of thirty, 9th grade boy students with intellectual disabilities in the selected schools; the schools were chosen by the multi-stage cluster method. To measure the progress of students in the science class, a teacher made test and the Wechsler intelligence test for matching the groups for IQ were used. To ensure validity, the content validity criteria depended tests calculated by the Lashe method and teachers' perspective were used. The reliability coefficient was obtained by the reliability coefficient of related tests; the percent agreement method and the obtained data were analyzed using one-way variance analysis and Shefe prosecution test. Results The results showed that there was a significant increase in academic achievement of students with intellectual disabilities when using token economy than using social reinforcements compared with the control group. Also, when using social reinforcements, the academic achievement of students was more than the control group. Conclusion Token economy and social reinforcements increased the academic achievement of students with intellectual disabilities in the science class; and also the effect of token economy reinforcements was more than social reinforcements on the subjects. PMID:22952517

  11. Insulator-based dielectrophoresis of microorganisms: theoretical and experimental results.

    PubMed

    Moncada-Hernandez, Hector; Baylon-Cardiel, Javier L; Pérez-González, Victor H; Lapizco-Encinas, Blanca H

    2011-09-01

    Dielectrophoresis (DEP) is the motion of particles due to polarization effects in nonuniform electric fields. DEP has great potential for handling cells and is a non-destructive phenomenon. It has been utilized for different cell analysis, from viability assessments to concentration enrichment and separation. Insulator-based DEP (iDEP) provides an attractive alternative to conventional electrode-based systems; in iDEP, insulating structures are used to generate nonuniform electric fields, resulting in simpler and more robust devices. Despite the rapid development of iDEP microdevices for applications with cells, the fundamentals behind the dielectrophoretic behavior of cells has not been fully elucidated. Understanding the theory behind iDEP is necessary to continue the progress in this field. This work presents the manipulation and separation of bacterial and yeast cells with iDEP. A computational model in COMSOL Multiphysics was employed to predict the effect of direct current-iDEP on cells suspended in a microchannel containing an array of insulating structures. The model allowed predicting particle behavior, pathlines and the regions where dielectrophoretic immobilization should occur. Experimental work was performed at the same operating conditions employed with the model and results were compared, obtaining good agreement. This is the first report on the mathematical modeling of the dielectrophoretic response of yeast and bacterial cells in a DC-iDEP microdevice. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Static properties of ferromagnetic quantum chains: Numerical results and experimental data on two S=1/2 systems (invited)

    NASA Astrophysics Data System (ADS)

    Kopinga, K.; Delica, T.; Leschke, H.

    1990-05-01

    New results of a variant of the numerically exact quantum transfer matrix method have been compared with experimental data on the static properties of [C6H11NH3]CuBr3(CHAB), a ferromagnetic system with about 5% easy-plane anisotropy. Above T=3.5 K, the available data on the zero-field heat capacity, the excess heat capacity ΔC=C(B)-C(B=0), and the magnetization are described with an accuracy comparable to the experimental error. Calculations of the spin-spin correlation functions reveal that the good description of the experimental correlation length in CHAB by a classical spin model is largely accidental. The zero-field susceptibility, which can be deduced from these correlation functions, is in fair agreement with the reported experimental data between 4 and 100 K. The method also seems to yield accurate results for the chlorine isomorph, CHAC, a system with about 2% uniaxial anisotropy.

  13. TGT for chemistry learning to enhance students' achievement and critical thinking skills

    NASA Astrophysics Data System (ADS)

    Bolhassan, Norlailatulakma; Taha, Hafsah

    2017-05-01

    The form of cooperative learning known as Teams-Games-Tournament (TGT) in this study favors the use of teams work and learning tools combined with student play and practice to foster students' achievement and critical thinking skills. Using this paradigm, this study incorporates Teams-Games-Tournament and Flash Cards Games Kit during an 8-weeks experimental instruction period that includes 67 Form Four students; 34 students in the experimental group and 33 in the control group. The learning design in experimental group emphasizes scaffolding, guided practices, cooperative learning, and active participation in learning. While the experimental group experienced the TGT approach, the control group encountered the conventional teaching approach of chemistry drills. An achievement chemistry test and Watson Glaser Critical Thinking Appraisal (WGCTA) were used for the pretest and posttest. The finding indicates that TGT learning was more effective than drills in promoting chemistry performance, and the playful competiveness among students promotes students' critical thinking. In addition, TGT cooperative learning also creates an active learning environment in solving problems and discussions among students and teachers.

  14. Association between Schoolwide Positive Behavioural Interventions and Supports and Academic Achievement: A 9-Year Evaluation

    ERIC Educational Resources Information Center

    Madigan, Kathleen; Cross, Richard W.; Smolkowski, Keith; Strycker, Lisa A.

    2016-01-01

    This study evaluated the long-term impact of schoolwide positive behavioural interventions and supports (PBIS) on student academic achievement. In this quasi-experimental study, academic achievement data were collected over 9 years. The 21 elementary, middle, and high schools that achieved moderate to high fidelity to the Save & Civil Schools'…

  15. The effects of guided inquiry instruction on student achievement in high school biology

    NASA Astrophysics Data System (ADS)

    Vass, Laszlo

    The purpose of this quantitative, quasi-experimental study was to measure the effect of a student-centered instructional method called guided inquiry on the achievement of students in a unit of study in high school biology. The study used a non-random sample of 109 students, the control group of 55 students enrolled in high school one, received teacher centered instruction while the experimental group of 54 students enrolled at high school two received student-centered, guided inquiry instruction. The pretest-posttest design of the study analyzed scores using an independent t-test, a dependent t-test (p = <.001), an ANCOVA (p = .007), mixed method ANOVA (p = .024) and hierarchical linear regression (p = <.001). The experimental group that received guided inquiry instruction had statistically significantly higher achievement than the control group.

  16. Physical activity and academic achievement across the curriculum: Results from a 3-year cluster-randomized trial.

    PubMed

    Donnelly, Joseph E; Hillman, Charles H; Greene, Jerry L; Hansen, David M; Gibson, Cheryl A; Sullivan, Debra K; Poggio, John; Mayo, Matthew S; Lambourne, Kate; Szabo-Reed, Amanda N; Herrmann, Stephen D; Honas, Jeffery J; Scudder, Mark R; Betts, Jessica L; Henley, Katherine; Hunt, Suzanne L; Washburn, Richard A

    2017-06-01

    We compared changes in academic achievement across 3years between children in elementary schools receiving the Academic Achievement and Physical Activity Across the Curriculum intervention (A+PAAC), in which classroom teachers were trained to deliver academic lessons using moderate-to-vigorous physical activity (MVPA) compared to a non-intervention control. Elementary schools in eastern Kansas (n=17) were cluster randomized to A+PAAC (N=9, target ≥100min/week) or control (N=8). Academic achievement (math, reading, spelling) was assessed using the Wechsler Individual Achievement Test-Third Edition (WIAT-III) in a sample of children (A+PAAC=316, Control=268) in grades 2 and 3 at baseline (Fall 2011) and repeated each spring across 3years. On average 55min/week of A+PACC lessons were delivered each week across the intervention. Baseline WIAT-III scores (math, reading, spelling) were significantly higher in students in A+PAAC compared with control schools and improved in both groups across 3years. However, linear mixed modeling, accounting for baseline between group differences in WIAT-III scores, ethnicity, family income, and cardiovascular fitness, found no significant impact of A+PAAC on any of the academic achievement outcomes as determined by non-significant group by time interactions. A+PAAC neither diminished or improved academic achievement across 3-years in elementary school children compared with controls. Our target of 100min/week of active lessons was not achieved; however, students attending A+PAAC schools received an additional 55min/week of MVPA which may be associated with both physical and mental health benefits, without a reduction in time devoted to academic instruction. Copyright © 2017. Published by Elsevier Inc.

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

    NASA Astrophysics Data System (ADS)

    Brown, Norman Merrill

    1998-09-01

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

  18. The Effect of Distributed Practice Homework on Precalculus Achievement at a Military Academy.

    DTIC Science & Technology

    1996-04-08

    This study investigated the main effect of distributive practice homework on achievement in Precalculus . This study also investigated the aptitude...achievement in Precalculus . The sample consisted of 351 United States Air Force Academy cadets (experimental n = 161, control n = 190), all in their first...achievement. A subset of the Math Anxiety Rating Scale developed by Alexander and Martray (1989) was used as the measure of mathematics anxiety. Precalculus

  19. Experimental Results from the Thermal Energy Storage-1 (TES-1) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Wald, Lawrence W.; Tolbert, Carol; Jacqmin, David

    1995-01-01

    The Thermal Energy Storage-1 (TES-1) is a flight experiment that flew on the Space Shuttle Columbia (STS-62), in March 1994, as part of the OAST-2 mission. TES-1 is the first experiment in a four experiment suite designed to provide data for understanding the long duration microgravity behavior of thermal energy storage fluoride salts that undergo repeated melting and freezing. Such data have never been obtained before and have direct application for the development of space-based solar dynamic (SD) power systems. These power systems will store solar energy in a thermal energy salt such as lithium fluoride or calcium fluoride. The stored energy is extracted during the shade portion of the orbit. This enables the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes have been developed for predicting performance of a spaced-based solar dynamic power system. Experimental verification of the analytical predictions is needed prior to using the analytical results for future space power design applications. The four TES flight experiments will be used to obtain the needed experimental data. This paper will focus on the flight results from the first experiment, TES-1, in comparison to the predicted results from the Thermal Energy Storage Simulation (TESSIM) analytical computer code. The TES-1 conceptual development, hardware design, final development, and system verification testing were accomplished at the NASA lewis Research Center (LeRC). TES-1 was developed under the In-Space Technology Experiment Program (IN-STEP), which sponsors NASA, industry, and university flight experiments designed to enable and enhance space flight technology. The IN-STEP Program is sponsored by the Office of Space Access and Technology (OSAT).

  20. Decentralized adaptive control of manipulators - Theory, simulation, and experimentation

    NASA Technical Reports Server (NTRS)

    Seraji, Homayoun

    1989-01-01

    The author presents a simple decentralized adaptive-control scheme for multijoint robot manipulators based on the independent joint control concept. The control objective is to achieve accurate tracking of desired joint trajectories. The proposed control scheme does not use the complex manipulator dynamic model, and each joint is controlled simply by a PID (proportional-integral-derivative) feedback controller and a position-velocity-acceleration feedforward controller, both with adjustable gains. Simulation results are given for a two-link direct-drive manipulator under adaptive independent joint control. The results illustrate trajectory tracking under coupled dynamics and varying payload. The proposed scheme is implemented on a MicroVAX II computer for motion control of the three major joints of a PUMA 560 arm. Experimental results are presented to demonstrate that trajectory tracking is achieved despite coupled nonlinear joint dynamics.

  1. The Effect of Brain Based Instruction on Student Achievement in Algebra I

    ERIC Educational Resources Information Center

    Vass, Melissa G.

    2010-01-01

    This quantitative quasi-experimental study examined the effect of brain-based instruction compared to teacher-centered instruction on student achievement in algebra I. A pre-test and post-test were given to a control group of 30 and experimental group of 42 before and after a unit if study in algebra I, which was taught using the two instructional…

  2. The effect of differentiated curriculum enhancements on the achievement of at-risk and normally achieving students in 5th grade science

    NASA Astrophysics Data System (ADS)

    Simpkins, Pamela Mccrea

    2007-12-01

    At-risk students show consistent patterns of under achievement and social maladjustment in school which leads to their demise in high school (McMillian & Reed, 1994). Similarly, special education students are at increased risk of not completing high school and do not perform as well on national achievement tests than their nondisabled peers (Land & Legters, 2002). It is possible that students at-risk for academic failure will not meet graduation requirements unless interventions are put in place to alleviate this problem. It has been documented that science textbooks contain difficult vocabulary and high reading levels that are challenging for struggling students. Using approaches such as activities oriented instruction, which supports the cooperative learning/peer tutoring model is one approach that has been successful with normally achieving and special education students. This research examined the effect of differentiated curriculum enhancements with peer tutoring on the achievement of at-risk and normally achieving students in science. A crossover design was implemented in three fifth grade inclusive classes, consisting of typically achieving students, students at-risk, and students with learning disabilities. The participants included 16 at-risk students, three special education students and 44 normally achieving students. The science review activities were implemented during two consecutive science units. One unit covered Earth and Space science. The other unit covered Light and Sound. Each curriculum enhancement had identification and production level activities. The identification level provided prompts; the production level did not provide prompts. Pretest and posttest were administered. Overall findings of the study revealed a significant interaction between experimental condition and treatment order, suggesting an advantage for students using differentiated curriculum enhancements. Main effects analysis suggested that students performed better on one

  3. Experimental Demonstration of Frequency Regulation by Commercial Buildings – Part II: Results and Performance Evaluation

    DOE PAGES

    Vrettos, Evangelos; Kara, Emre Can; MacDonald, Jason; ...

    2016-11-15

    This paper is the second part of a two-part series presenting the results from an experimental demonstration of frequency regulation in a commercial building test facility. We developed relevant building models and designed a hierarchical controller for reserve scheduling, building climate control and frequency regulation in Part I. In Part II, we introduce the communication architecture and experiment settings, and present extensive experimental results under frequency regulation. More specifically, we compute the day-ahead reserve capacity of the test facility under different assumptions and conditions. Furthermore, we demonstrate the ability of model predictive control to satisfy comfort constraints under frequency regulation,more » and show that fan speed control can track the fast-moving RegD signal of the Pennsylvania, Jersey, and Maryland Power Market (PJM) very accurately. In addition, we discuss potential effects of frequency regulation on building operation (e.g., increase in energy consumption, oscillations in supply air temperature, and effect on chiller cycling), and provide suggestions for real-world implementation projects. Our results show that hierarchical control is appropriate for frequency regulation from commercial buildings.« less

  4. VX hydrolysis by human serum paraoxonase 1: a comparison of experimental and computational results.

    PubMed

    Peterson, Matthew W; Fairchild, Steven Z; Otto, Tamara C; Mohtashemi, Mojdeh; Cerasoli, Douglas M; Chang, Wenling E

    2011-01-01

    Human Serum paraoxonase 1 (HuPON1) is an enzyme that has been shown to hydrolyze a variety of chemicals including the nerve agent VX. While wildtype HuPON1 does not exhibit sufficient activity against VX to be used as an in vivo countermeasure, it has been suggested that increasing HuPON1's organophosphorous hydrolase activity by one or two orders of magnitude would make the enzyme suitable for this purpose. The binding interaction between HuPON1 and VX has recently been modeled, but the mechanism for VX hydrolysis is still unknown. In this study, we created a transition state model for VX hydrolysis (VX(ts)) in water using quantum mechanical/molecular mechanical simulations, and docked the transition state model to 22 experimentally characterized HuPON1 variants using AutoDock Vina. The HuPON1-VX(ts) complexes were grouped by reaction mechanism using a novel clustering procedure. The average Vina interaction energies for different clusters were compared to the experimentally determined activities of HuPON1 variants to determine which computational procedures best predict how well HuPON1 variants will hydrolyze VX. The analysis showed that only conformations which have the attacking hydroxyl group of VX(ts) coordinated by the sidechain oxygen of D269 have a significant correlation with experimental results. The results from this study can be used for further characterization of how HuPON1 hydrolyzes VX and design of HuPON1 variants with increased activity against VX.

  5. Assessing Students' Experimentation Processes in Guided Inquiry

    ERIC Educational Resources Information Center

    Emden, Markus; Sumfleth, Elke

    2016-01-01

    In recent science education, experimentation features ever more strongly as a method of inquiry in science classes rather than as a means to illustrate phenomena. Ideas and materials to teach inquiry abound. Yet, tools for assessing students' achievement in their processes of experimentation are lacking. The present study assumes a basal,…

  6. Comparison of Experimental Surface and Flow Field Measurements to Computational Results of the Juncture Flow Model

    NASA Technical Reports Server (NTRS)

    Roozeboom, Nettie H.; Lee, Henry C.; Simurda, Laura J.; Zilliac, Gregory G.; Pulliam, Thomas H.

    2016-01-01

    Wing-body juncture flow fields on commercial aircraft configurations are challenging to compute accurately. The NASA Advanced Air Vehicle Program's juncture flow committee is designing an experiment to provide data to improve Computational Fluid Dynamics (CFD) modeling in the juncture flow region. Preliminary design of the model was done using CFD, yet CFD tends to over-predict the separation in the juncture flow region. Risk reduction wind tunnel tests were requisitioned by the committee to obtain a better understanding of the flow characteristics of the designed models. NASA Ames Research Center's Fluid Mechanics Lab performed one of the risk reduction tests. The results of one case, accompanied by CFD simulations, are presented in this paper. Experimental results suggest the wall mounted wind tunnel model produces a thicker boundary layer on the fuselage than the CFD predictions, resulting in a larger wing horseshoe vortex suppressing the side of body separation in the juncture flow region. Compared to experimental results, CFD predicts a thinner boundary layer on the fuselage generates a weaker wing horseshoe vortex resulting in a larger side of body separation.

  7. Numerical and experimental modelling of the radial compressor stage

    NASA Astrophysics Data System (ADS)

    Syka, Tomáš; Matas, Richard; LuÅáček, Ondřej

    2016-06-01

    This article deals with the description of the numerical and experimental model of the new compressor stage designed for process centrifugal compressors. It's the first member of the new stages family developed to achieve the state of the art thermodynamic parameters. This stage (named RTK01) is designed for high flow coefficient with 3D shaped impeller blades. Some interesting findings were gained during its development. The article is focused mainly on some interesting aspects of the development methodology and numerical simulations improvement, not on the specific stage properties. Conditions and experimental equipment, measured results and their comparison with ANSYS CFX and NUMECA FINE/Turbo CFD simulations are described.

  8. Scoliosis correction with shape-memory metal: results of an experimental study.

    PubMed

    Wever, D J; Elstrodt, J A; Veldhuizen, A G; v Horn, J R

    2002-04-01

    The biocompatibility and functionality of a new scoliosis correction device, based on the properties of the shape-memory metal nickel-titanium alloy, were studied. With this device, the shape recovery forces of a shape-memory metal rod are used to achieve a gradual three-dimensional scoliosis correction. In the experimental study the action of the new device was inverted: the device was used to induce a scoliotic curve instead of correcting one. Surgical procedures were performed in six pigs. An originally curved squared rod, in the cold condition, was straightened and fixed to the spine with pedicle screws. Peroperatively, the memory effect of the rod was activated by heating the rod to 50 degrees C by a low-voltage, high-frequency current. After 3 and after 6 months the animals were sacrificed. The first radiographs, obtained immediately after surgery, showed in all animals an induced curve of about 40 degrees Cobb angle - the original curve of the rod. This curve remained constant during the follow-up. The postoperative serum nickel measurements were around the detection limit, and were not significantly higher compared to the preoperative nickel concentration. Macroscopic inspection after 3 and 6 months showed that the device was almost overgrown with newly formed bone. Corrosion and fretting processes were not observed. Histologic examination of the sections of the surrounding tissues and sections of the lung, liver, spleen and kidney showed no evidence of a foreign body response. In view of the initiation of the scoliotic deformation, it is expected that the shape-memory metal based scoliosis correction device also has the capacity to correct a scoliotic curve. Moreover, it is expected that the new device will show good biocompatibility in clinical application. Extensive fatigue testing of the whole system should be performed before clinical trials are initiated.

  9. Experimental demonstration of free-space based 120 Gb/s reconfigurable card-to-card optical interconnects.

    PubMed

    Wang, Ke; Nirmalathas, Ampalavanapillai; Lim, Christina; Skafidas, Efstratios; Alameh, Kamal

    2014-10-01

    In this Letter, we propose and experimentally demonstrate a free-space based reconfigurable card-to-card optical interconnect architecture with 16-carrierless-amplitude-phase modulation. Experimental results show that up to 120 Gb/s (3×40  Gb/s) flexible interconnection can be achieved for up to 30 cm distance with a worst-case receiver sensitivity of -9.70  dBm.

  10. The Effect of Manipulatives on Mathematics Achievement and Attitudes of Secondary School Students

    ERIC Educational Resources Information Center

    Kontas, Hakki

    2016-01-01

    The purpose of this study is to investigate the effect of manipulatives (concrete learning materials) both on the academic achievement of secondary school students in mathematics and on their attitudes towards mathematics. Pretest-posttest control group experimental model, which is one of the quasi-experimental research designs, was used in the…

  11. Accelerating the development of formal thinking in middle and high school students II: Postproject effects on science achievement

    NASA Astrophysics Data System (ADS)

    Shayer, Michael; Adey, Philip S.

    A one-year lag was found between the effect of an intervention intended to promote formal operational thinking in students initially 11 or 12 years of age and the appearance of substantial science achievement in the experimental groups. A one-year lag was also reported on cognitive development: Whereas at the end of the two-year intervention the experimental groups were up to 0.9 ahead of the control groups, one year later the differential on Piagetian measures had disappeared, but the experimentals now showed better science achievement of even greater magnitude. Although the control groups showed normal distribution both on science achievement and cognitive development, the experimental groups showed bi- or trimodal distribution. Between one-half and one-quarter of the students involved in the experiment in different groups showed effects of the order of 2 both on cognitive development and science achievement; some students appeared unaffected (compared with the controls), and others demonstrated modest effects on science achievement. An age/gender interaction is reported: the most substantial effects were found in boys initially aged 12+ and girls initially 11+. The only group to show no effects was boys initially aged 11+. It is suggested that the intervention methods may have favored the abstract analytical learning style as described by Cohen 1986.

  12. Effects of Cooperative Learning on Learning Achievement and Group Working Behavior of Junior Students in Modern French Literature Course

    ERIC Educational Resources Information Center

    Orprayoon, Soudaya

    2014-01-01

    This study reported on the results of a quasi-experimental research to explore the effectiveness of using a cooperative learning method on students' academic achievement, their group working behavior and their perception and opinions towards cooperative learning in a Modern French Literature course. The sample included twelve junior students…

  13. Taking advantage of ground data systems attributes to achieve quality results in testing software

    NASA Technical Reports Server (NTRS)

    Sigman, Clayton B.; Koslosky, John T.; Hageman, Barbara H.

    1994-01-01

    During the software development life cycle process, basic testing starts with the development team. At the end of the development process, an acceptance test is performed for the user to ensure that the deliverable is acceptable. Ideally, the delivery is an operational product with zero defects. However, the goal of zero defects is normally not achieved but is successful to various degrees. With the emphasis on building low cost ground support systems while maintaining a quality product, a key element in the test process is simulator capability. This paper reviews the Transportable Payload Operations Control Center (TPOCC) Advanced Spacecraft Simulator (TASS) test tool that is used in the acceptance test process for unmanned satellite operations control centers. The TASS is designed to support the development, test and operational environments of the Goddard Space Flight Center (GSFC) operations control centers. The TASS uses the same basic architecture as the operations control center. This architecture is characterized by its use of distributed processing, industry standards, commercial off-the-shelf (COTS) hardware and software components, and reusable software. The TASS uses much of the same TPOCC architecture and reusable software that the operations control center developer uses. The TASS also makes use of reusable simulator software in the mission specific versions of the TASS. Very little new software needs to be developed, mainly mission specific telemetry communication and command processing software. By taking advantage of the ground data system attributes, successful software reuse for operational systems provides the opportunity to extend the reuse concept into the test area. Consistency in test approach is a major step in achieving quality results.

  14. Enhancing Mathematics Achievement of Elementary School Students through Homework Assignments Enriched with Metacognitive Questions

    ERIC Educational Resources Information Center

    Özcan, Zeynep Çigdem; Erktin, Emine

    2015-01-01

    Metacognitive enrichment has become an important component of modern mathematics instruction. This study investigates the effect of homework assignments enriched with metacognitive questions on students' mathematics achievement and homework behaviors. A quasi-experimental design with pre- and post-test measures and two groups (experimental and…

  15. Comparison of experimental data with results of some drying models for regularly shaped products

    NASA Astrophysics Data System (ADS)

    Kaya, Ahmet; Aydın, Orhan; Dincer, Ibrahim

    2010-05-01

    This paper presents an experimental and theoretical investigation of drying of moist slab, cylinder and spherical products to study dimensionless moisture content distributions and their comparisons. Experimental study includes the measurement of the moisture content distributions of slab and cylindrical carrot, slab and cylindrical pumpkin and spherical blueberry during drying at various temperatures (e.g., 30, 40, 50 and 60°C) at specific constant velocity ( U = 1 m/s) and the relative humidity φ = 30%. In theoretical analysis, two moisture transfer models are used to determine drying process parameters (e.g., drying coefficient and lag factor) and moisture transfer parameters (e.g., moisture diffusivity and moisture transfer coefficient), and to calculate the dimensionless moisture content distributions. The calculated results are then compared with the experimental moisture data. A considerably high agreement is obtained between the calculations and experimental measurements for the cases considered. The effective diffusivity values were evaluated between 0.741 × 10-5 and 5.981 × 10-5 m2/h for slab products, 0.818 × 10-5 and 6.287 × 10-5 m2/h for cylindrical products and 1.213 × 10-7 and 7.589 × 10-7 m2/h spherical products using the Model-I and 0.316 × 10-5-5.072 × 10-5 m2/h for slab products, 0.580 × 10-5-9.587 × 10-5 m2/h for cylindrical products and 1.408 × 10-7-13.913 × 10-7 m2/h spherical products using the Model-II.

  16. Experimental results on the ω- and η'-nucleus potential - on the way to mesic states

    NASA Astrophysics Data System (ADS)

    Nanova, Mariana

    2015-06-01

    Different experimental approaches to determine the meson-nucleus optical potential are discussed. The experiments have been performed with the Crystal Barrel/TAPS detector system at the ELSA accelerator in Bonn and the Crystal Ball/TAPS at the MAMI accelerator in Mainz. Experimental results about the real and imaginary part of the η'- and ω-nucleus optical potential are presented. The imaginary part of the meson-nucleus optical potential is determined from the in-medium width of the meson by the measurement of the transparency ratio. Information on the real part of the optical potential is deduced from measurements of the excitation function and momentum distribution which are sensitive to the sign and depth of the potential. The results are discussed and compared to theoretical predictions. The data for both mesons are consistent with a weakly attractive potential. The formation and population of ω-nucleus and η'-nucleus bound states is additionally discussed.

  17. Comparing the Impacts of Tutorial and Edutainment Software Programs on Students' Achievements, Misconceptions, and Attitudes towards Biology

    NASA Astrophysics Data System (ADS)

    Kara, Yılmaz; Yeşilyurt, Selami

    2008-02-01

    The purpose of this study was to investigate the effects of tutorial and edutainment design of instructional software programs related to the "cell division" topic on student achievements, misconceptions and attitudes. An experimental research design including the cell division achievement test (CAT), the cell division concept test (CCT) and biology attitude scale (BAS) was applied at the beginning and at the end of the research. After the treatment, general achievement in CAT increased in favor of experimental groups. Instructional software programs also had the positive effect to the awareness of students' understandings to the general functions of mitosis and meiosis. However, the current study revealed that there were still some misconceptions in the experimental groups even after the treatment. It was also noticed that only using edutainment software program significantly changed students' attitudes towards biology.

  18. The Impacts of Remedial Interventions on Learning Chinese for Low-Achieving First Graders

    ERIC Educational Resources Information Center

    Chen, Shu-Li; Tzeng, Shih-Jay; Chu, Szu-Yin; Chen, Hsin-Ying

    2016-01-01

    The purpose of this study was to investigate whether a Chinese phonetic script, Zhu-Yin-Fu-Hao (ZYFH), influences low achievers in learning Chinese. In this quasi experimental design, 21 students were assigned to the experimental group, while the other 31 students were distributed to the control group. Two interventions were implemented throughout…

  19. Feingold Diet Effect on Reading Achievement and Classroom Behavior.

    ERIC Educational Resources Information Center

    Chernick, Eleanor

    The effect of the Feingold diet (elimination of artificial colors, flavors, or foods with natural salicylates to reduce hyperactivity) on the reading achievement scores, behavior, and impulsivity/reflectivity of 13 children (ages 6 to 12 years) was evaluated. Six months after the experimental group adopted the Feingold diet there were no…

  20. Social Identity and Achievement Gaps: Evidence from an Affirmation Intervention

    ERIC Educational Resources Information Center

    Dee, Thomas S.

    2015-01-01

    One provocative explanation for the continued persistence of minority achievement gaps involves the performance-dampening anxiety thought to be experienced by minority students in highly evaluative settings (i.e., "stereotype threat"). Recent field-experimental studies suggest that modest, low-cost "buffering" interventions…

  1. Comparison between maximum radial expansion of ultrasound contrast agents and experimental postexcitation signal results.

    PubMed

    King, Daniel A; O'Brien, William D

    2011-01-01

    Experimental postexcitation signal data of collapsing Definity microbubbles are compared with the Marmottant theoretical model for large amplitude oscillations of ultrasound contrast agents (UCAs). After taking into account the insonifying pulse characteristics and size distribution of the population of UCAs, a good comparison between simulated results and previously measured experimental data is obtained by determining a threshold maximum radial expansion (Rmax) to indicate the onset of postexcitation. This threshold Rmax is found to range from 3.4 to 8.0 times the initial bubble radius, R0, depending on insonification frequency. These values are well above the typical free bubble inertial cavitation threshold commonly chosen at 2R0. The close agreement between the experiment and models suggests that lipid-shelled UCAs behave as unshelled bubbles during most of a large amplitude cavitation cycle, as proposed in the Marmottant equation.

  2. Hemostasis of the liver, spleen, and bone achieved by electrocautery greased with lidocaine gel.

    PubMed

    Petroianu, Andy

    2011-02-01

    Despite advances in surgical techniques, achieving hemostasis of the liver, spleen, and bone during major surgery, especially after trauma, is still difficult. I describe a new procedure my colleagues and I devised to achieve parenchymatous hemostasis using electrocautery greased with lidocaine gel. After achieving good results in experimental studies and obtaining approval from our ethics committee, we used electrocautery greased with lidocaine gel for hemostasis in the following 36 procedures: multisegmental hepatectomy to remove hepatic tumors (n = 6); partial hepatectomy to allow hepatojejunostomy for intrahepatic biliary obstruction (n = 10); laparoscopic liver biopsy (n = 4); subtotal splenectomy (n = 8; for portal hypertension in 5 patients, splenic ischemia in 2, and Gaucher's disease in 1); laparoscopic splenic biopsy (n = 1); and bone resection (n = 7; as pelvic-femoral resection in 6 patients and to remove a rectal tumor invading the coccyx in 1). This procedure was easy to perform and achieved complete hemostasis of the minor blood vessels in all patients. No postoperative bleeding occurred and the follow-up course was satisfactory. Electrocautery greased with lidocaine gel is an inexpensive, readily available, and efficient method to achieve hemostasis of minor vessels in hepatic, splenic, and bone operations.

  3. Experimental study on secondary electron emission characteristics of Cu

    NASA Astrophysics Data System (ADS)

    Liu, Shenghua; Liu, Yudong; Wang, Pengcheng; Liu, Weibin; Pei, Guoxi; Zeng, Lei; Sun, Xiaoyang

    2018-02-01

    Secondary electron emission (SEE) of a surface is the origin of the multipacting effect which could seriously deteriorate beam quality and even perturb the normal operation of particle accelerators. Experimental measurements on secondary electron yield (SEY) for different materials and coatings have been developed in many accelerator laboratories. In fact, the SEY is just one parameter of secondary electron emission characteristics which include spatial and energy distribution of emitted electrons. A novel experimental apparatus was set up in China Spallation Neutron Source, and an innovative method was applied to obtain the whole characteristics of SEE. Taking Cu as the sample, secondary electron yield, its dependence on beam injection angle, and the spatial and energy distribution of secondary electrons were achieved with this measurement device. The method for spatial distribution measurement was first proposed and verified experimentally. This contribution also tries to give all the experimental results a reasonable theoretical analysis and explanation.

  4. Examining the Relationship of Textbooks and Labs on Student Achievement in Eighth-Grade Science

    NASA Astrophysics Data System (ADS)

    Sugalan, Anacita Noromor

    One of the most important objectives of teachers, parents, school administrators, and students is to improve student scores on standardized tests such as the State of Texas Assessment for Academic Readiness (STAAR) in eighth-grade science. This quasi experimental study examined the science achievement scores between schools that use textbooks and labs when delivering instruction. This study utilized a quantitative approach using archival data and survey design. Analysis of covariance (ANCOVA) and multiple regression were used to analyze the data while controlling STAAR eighth-grade reading scores to reveal significant differences between classes. The sample and population for this study were predominantly eighth-grade Hispanic students in South Texas. Analysis of covariance showed that classes that used high labs got higher science scores and that the reading scores were significantly related to science scores. Multiple regression findings indicated that textbooks and labs were significant predictors of student achievement on the STAAR eighth- grade science class result in South Texas for Spring 2015. The findings of this study may serve as a catalyst for improving student achievement in science through changes in textbook adoption and doing labs in science. The result suggests the need to research further to investigate other contributing factors of student achievement.

  5. Individuals Achieve More Accurate Results with Meters That Are Codeless and Employ Dynamic Electrochemistry

    PubMed Central

    Rao, Anoop; Wiley, Meg; Iyengar, Sridhar; Nadeau, Dan; Carnevale, Julie

    2010-01-01

    Background Studies have shown that controlling blood glucose can reduce the onset and progression of the long-term microvascular and neuropathic complications associated with the chronic course of diabetes mellitus. Improved glycemic control can be achieved by frequent testing combined with changes in medication, exercise, and diet. Technological advancements have enabled improvements in analytical accuracy of meters, and this paper explores two such parameters to which that accuracy can be attributed. Methods Four blood glucose monitoring systems (with or without dynamic electrochemistry algorithms, codeless or requiring coding prior to testing) were evaluated and compared with respect to their accuracy. Results Altogether, 108 blood glucose values were obtained for each system from 54 study participants and compared with the reference values. The analysis depicted in the International Organization for Standardization table format indicates that the devices with dynamic electrochemistry and the codeless feature had the highest proportion of acceptable results overall (System A, 101/103). Results were significant when compared at the 10% bias level with meters that were codeless and utilized static electrochemistry (p = .017) or systems that had static electrochemistry but needed coding (p = .008). Conclusions Analytical performance of these blood glucose meters differed significantly depending on their technologic features. Meters that utilized dynamic electrochemistry and did not require coding were more accurate than meters that used static electrochemistry or required coding. PMID:20167178

  6. Investigation of sonar transponders for offshore wind farms: modeling approach, experimental setup, and results.

    PubMed

    Fricke, Moritz B; Rolfes, Raimund

    2013-11-01

    The installation of offshore wind farms in the German Exclusive Economic Zone requires the deployment of sonar transponders to prevent collisions with submarines. The general requirements for these systems have been previously worked out by the Research Department for Underwater Acoustics and Marine Geophysics of the Bundeswehr. In this article, the major results of the research project "Investigation of Sonar Transponders for Offshore Wind Farms" are presented. For theoretical investigations a hybrid approach was implemented using the boundary element method to calculate the source directivity and a three-dimensional ray-tracing algorithm to estimate the transmission loss. The angle-dependence of the sound field as well as the weather-dependence of the transmission loss are compared to experimental results gathered at the offshore wind farm alpha ventus, located 45 km north of the island Borkum. While theoretical and experimental results are in general agreement, the implemented model slightly underestimates scattering at the rough sea surface. It is found that the source level of 200 dB re 1 μPa at 1 m is adequate to satisfy the detectability of the warning sequence at distances up to 2 NM (≈3.7 km) within a horizontal sector of ±60° if realistic assumptions about signal-processing and noise are made. An arrangement to enlarge the angular coverage is discussed.

  7. A comparison of experimental and theoretical results for labyrinth gas seals with honeycomb stators. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Hawkins, Lawrence Allen

    1988-01-01

    Experimental results for the rotordynamic stiffness and damping coefficients of a labyrinth -rotor honeycomb-stator seal are presented. The coefficients are compared to the coefficients of a labyrinth-rotor smooth-stator seal having the same geometry. The coefficients are compared to analytical results from a two-control-volume compressible flow model. The experimental results show that the honeycomb stator configuration is more stable than the smooth stator configuration at low rotor speeds. At high rotor speeds and low clearance, the smooth stator seal is more stable. The theoretical model predicts the cross-coupled stiffness of the honeycomb stator seal correctly within 25 percent of measured values. The model provides accurate predictions of direct damping for large clearance seals. Overall, the model does not perform as well for low clearance seals as for high clearance seals.

  8. Effects of a Collaborative Science Intervention on High Achieving Students' Learning Anxiety and Attitudes toward Science

    NASA Astrophysics Data System (ADS)

    Hong, Zuway-R.

    2010-10-01

    This study investigated the effects of a collaborative science intervention on high achieving students' learning anxiety and attitudes toward science. Thirty-seven eighth-grade high achieving students (16 boys and 21 girls) were selected as an experimental group who joined a 20-week collaborative science intervention, which integrated and utilized an innovative teaching strategy. Fifty-eight eighth-grade high achieving students were selected as the comparison group. The Secondary School Student Questionnaire was conducted to measure all participants' learning anxiety and attitudes toward science. In addition, 12 target students from the experimental group (i.e., six active and six passive students) were recruited for weekly classroom observations and follow-up interviews during the intervention. Both quantitative and qualitative findings revealed that experimental group students experienced significant impact as seen through increased attitudes and decreased anxiety of learning science. Implications for practice and research are provided.

  9. Using Advance Organizers to Enhance Pupils' Achievement in Learning Poetry in English Language

    ERIC Educational Resources Information Center

    Muiruri, Mary; Wambugu, Patriciah; Wamukuru, Kuria

    2016-01-01

    The study was a quasi-experimental that investigated the effects of Advance Organizers (AO) on achievement in poetry. Target population was class seven pupils of Nakuru North Sub-county primary schools in Kenya. 160 pupils were involved in the study. Four sampled schools were randomly assigned to control and experimental groups in Solomon Four…

  10. Noise characteristics of upper surface blown configurations. Experimental program and results

    NASA Technical Reports Server (NTRS)

    Brown, W. H.; Searle, N.; Blakney, D. F.; Pennock, A. P.; Gibson, J. S.

    1977-01-01

    An experimental data base was developed from the model upper surface blowing (USB) propulsive lift system hardware. While the emphasis was on far field noise data, a considerable amount of relevant flow field data were also obtained. The data were derived from experiments in four different facilities resulting in: (1) small scale static flow field data; (2) small scale static noise data; (3) small scale simulated forward speed noise and load data; and (4) limited larger-scale static noise flow field and load data. All of the small scale tests used the same USB flap parts. Operational and geometrical variables covered in the test program included jet velocity, nozzle shape, nozzle area, nozzle impingement angle, nozzle vertical and horizontal location, flap length, flap deflection angle, and flap radius of curvature.

  11. School Climate, Peer Victimization, and Academic Achievement: Results from a Multi-Informant Study

    ERIC Educational Resources Information Center

    Wang, Weijun; Vaillancourt, Tracy; Brittain, Heather L.; McDougall, Patricia; Krygsman, Amanda; Smith, David; Cunningham, Charles E.; Haltigan, J. D.; Hymel, Shelley

    2014-01-01

    School-level school climate was examined in relation to self-reported peer victimization and teacher-rated academic achievement (grade point average; GPA). Participants included a sample of 1,023 fifth-grade children nested within 50 schools. Associations between peer victimization, school climate, and GPA were examined using multilevel modeling,…

  12. Water-waves on linear shear currents. A comparison of experimental and numerical results.

    NASA Astrophysics Data System (ADS)

    Simon, Bruno; Seez, William; Touboul, Julien; Rey, Vincent; Abid, Malek; Kharif, Christian

    2016-04-01

    Propagation of water waves can be described for uniformly sheared current conditions. Indeed, some mathematical simplifications remain applicable in the study of waves whether there is no current or a linearly sheared current. However, the widespread use of mathematical wave theories including shear has rarely been backed by experimental studies of such flows. New experimental and numerical methods were both recently developed to study wave current interactions for constant vorticity. On one hand, the numerical code can simulate, in two dimensions, arbitrary non-linear waves. On the other hand, the experimental methods can be used to generate waves with various shear conditions. Taking advantage of the simplicity of the experimental protocol and versatility of the numerical code, comparisons between experimental and numerical data are discussed and compared with linear theory for validation of the methods. ACKNOWLEDGEMENTS The DGA (Direction Générale de l'Armement, France) is acknowledged for its financial support through the ANR grant N° ANR-13-ASTR-0007.

  13. Analysis of Dynamic Fracture Compliance Based on Poroelastic Theory - Part II: Results of Numerical and Experimental Tests

    NASA Astrophysics Data System (ADS)

    Wang, Ding; Ding, Pin-bo; Ba, Jing

    2018-03-01

    In Part I, a dynamic fracture compliance model (DFCM) was derived based on the poroelastic theory. The normal compliance of fractures is frequency-dependent and closely associated with the connectivity of porous media. In this paper, we first compare the DFCM with previous fractured media theories in the literature in a full frequency range. Furthermore, experimental tests are performed on synthetic rock specimens, and the DFCM is compared with the experimental data in the ultrasonic frequency band. Synthetic rock specimens saturated with water have more realistic mineral compositions and pore structures relative to previous works in comparison with natural reservoir rocks. The fracture/pore geometrical and physical parameters can be controlled to replicate approximately those of natural rocks. P- and S-wave anisotropy characteristics with different fracture and pore properties are calculated and numerical results are compared with experimental data. Although the measurement frequency is relatively high, the results of DFCM are appropriate for explaining the experimental data. The characteristic frequency of fluid pressure equilibration calculated based on the specimen parameters is not substantially less than the measurement frequency. In the dynamic fracture model, the wave-induced fluid flow behavior is an important factor for the fracture-wave interaction process, which differs from the models at the high-frequency limits, for instance, Hudson's un-relaxed model.

  14. Fines migration during CO 2 injection: Experimental results interpreted using surface forces

    DOE PAGES

    Xie, Quan; Saeedi, Ali; Delle Piane, Claudio; ...

    2017-09-04

    The South West Hub project is one of the Australian Flagship Carbon Capture and Storage projects located in the south-west of Western Australia. To evaluate the injectivity potential during the forthcoming full-scale CO 2 injection, we conducted three core-flooding experiments using reservoir core plugs from the well Harvey-1. We aimed to investigate in this paper whether the injection of CO 2 leads to fines migration and permeability reduction due to the relatively high kaolinite content (up to 13%) in the injection interval of the target formation (i.e. the Wonnerup Member of the Lesueur Formation). We imaged the core samples beforemore » flooding to verify the presence of kaolinite at the pore-scale using scanning electron microscopy (SEM). We also examined the pore network of the core plugs before and after the core-flooding experiments using Nuclear Magnetic Resonance (NMR). Moreover, to gain a better understanding of any kaolinite fines migration, we delineated surface force using two models based on Derjaguin-Landau-Verwey-Overbeek (denoted by DLVO) theory coupled hydrodynamic force: (1) sphere/flat model representing interaction between kaolinite/quartz, and (2) flat/flat model representing interaction between kaolinite/kaolinite. Our core-flooding experimental results showed that CO 2/brine injection triggered moderate to significant reduction in the permeability of the core samples with a negligible porosity change. NMR measurements supported the core-flooding results, suggesting that the relatively large pores disappeared in favour of a higher proportion of the medium to small pores after flooding. The DLVO calculations showed that some kaolinite particles probably lifted off and detached from neighbouring kaolinite particles rather than quartz grains. Moreover, the modelling results showed that the kaolinite fines migration would not occur under normal reservoir multiphase flow conditions. This is not because of the low hydrodynamic force. It is

  15. Fines migration during CO 2 injection: Experimental results interpreted using surface forces

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xie, Quan; Saeedi, Ali; Delle Piane, Claudio

    The South West Hub project is one of the Australian Flagship Carbon Capture and Storage projects located in the south-west of Western Australia. To evaluate the injectivity potential during the forthcoming full-scale CO 2 injection, we conducted three core-flooding experiments using reservoir core plugs from the well Harvey-1. We aimed to investigate in this paper whether the injection of CO 2 leads to fines migration and permeability reduction due to the relatively high kaolinite content (up to 13%) in the injection interval of the target formation (i.e. the Wonnerup Member of the Lesueur Formation). We imaged the core samples beforemore » flooding to verify the presence of kaolinite at the pore-scale using scanning electron microscopy (SEM). We also examined the pore network of the core plugs before and after the core-flooding experiments using Nuclear Magnetic Resonance (NMR). Moreover, to gain a better understanding of any kaolinite fines migration, we delineated surface force using two models based on Derjaguin-Landau-Verwey-Overbeek (denoted by DLVO) theory coupled hydrodynamic force: (1) sphere/flat model representing interaction between kaolinite/quartz, and (2) flat/flat model representing interaction between kaolinite/kaolinite. Our core-flooding experimental results showed that CO 2/brine injection triggered moderate to significant reduction in the permeability of the core samples with a negligible porosity change. NMR measurements supported the core-flooding results, suggesting that the relatively large pores disappeared in favour of a higher proportion of the medium to small pores after flooding. The DLVO calculations showed that some kaolinite particles probably lifted off and detached from neighbouring kaolinite particles rather than quartz grains. Moreover, the modelling results showed that the kaolinite fines migration would not occur under normal reservoir multiphase flow conditions. This is not because of the low hydrodynamic force. It is

  16. Optimal active vibration absorber: Design and experimental results

    NASA Technical Reports Server (NTRS)

    Lee-Glauser, Gina; Juang, Jer-Nan; Sulla, Jeffrey L.

    1992-01-01

    An optimal active vibration absorber can provide guaranteed closed-loop stability and control for large flexible space structures with collocated sensors/actuators. The active vibration absorber is a second-order dynamic system which is designed to suppress any unwanted structural vibration. This can be designed with minimum knowledge of the controlled system. Two methods for optimizing the active vibration absorber parameters are illustrated: minimum resonant amplitude and frequency matched active controllers. The Controls-Structures Interaction Phase-1 Evolutionary Model at NASA LaRC is used to demonstrate the effectiveness of the active vibration absorber for vibration suppression. Performance is compared numerically and experimentally using acceleration feedback.

  17. [Energy saving achieved by limited filamentous bulking under low dissolved oxygen: experimental validation in A/O process].

    PubMed

    Guo, Jian-hua; Wang, Shu-ying; Peng, Yong-zhen; Zheng, Ya-nan; Huang, Hui-jun; Ge, Shi-jian; Sun, Zhi-rong

    2008-12-01

    Preliminary studies had been conducted to determine the correctness of the theory and technique of energy saving achieved by limited filamentous bulking under low DO using a lab-scale A/O reactor with real domestic wastewater as the influent. The results showed that SVI could be maintained 150-230 mL/g and sludge settleability would not become very poor under the condition of low DO. During the period of limited filamentous bulking, COD and total nitrogen removal efficiencies were improved, and distinct simultaneous nitrification and denitrification (SND) was achieved, while ammonia removal efficiency would slightly decline with decreasing of DO, compared with the period of good settleability sludge under high DO. COD, ammonia and total nitrogen removal efficiencies were 86%, 70% and 63%, respectively. It was found that about 10%-25% nitrogen would be removed by SND based on the mass balance of nitrogen. Besides, SS in the effluent was almost negligible and the effluent turbidity was lower than 3 NTU. Significantly, aeration consumptions would be decreased by 17% under the condition with DO of 0.5 mg/L compared with 2.0 mg/L according to theoretical calculation of air requirements to keep different DO levels, which was about 57% in lab-scale reactor correspondingly.

  18. Effect of Cooperative Learning on Achievement of Students in General Science at Secondary Level

    ERIC Educational Resources Information Center

    Parveen, Qaisara; Batool, Sadia

    2012-01-01

    The aim of the study was to explore the effects of cooperative learning on General Science achievement among 9th class students. Based upon previous research literature it was hypothesized that significant difference existed between the mean posttest scores of General Science achievement of experimental group and control group. The pretest…

  19. EPA Science to Achieve Results (STAR) Centers for Water Research on National Priorities Related to a Systems View of Nutrient Management

    EPA Science Inventory

    This poster describes the missions and objectives of four newly-awarded Science to Achieve Results (STAR) Centers. There is also a description of how the projects fit together to meet solicitation research questions.

  20. Rotating Fluidized Bed Reactor for Space Nuclear Propulsion. Annual Report; Design Studies and Experimental Results

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The rotating fluidized bed reactor concept is being investigated for possible application in nuclear propulsion systems. Physics calculations show U-233 to be superior to U-235 as a fuel for a cavity reactor of this type. Preliminary estimates of the effect of hydrogen in the reactor, reflector material, and power peaking are given. A preliminary engineering analysis was made for U-235 and U-233 fueled systems. An evaluation of the parameters affecting the design of the system is given, along with the thrust-to-weight ratios. The experimental equipment is described, as are the special photographic techniques and procedures. Characteristics of the fluidized bed and experimental results are given, including photographic evidence of bed fluidization at high rotational velocities.

  1. Survey of Experimental Results in High-Contrast Imaging for Future Exoplanet Missions

    NASA Technical Reports Server (NTRS)

    Lawson, P. R.; Belikov, R.; Cash, W.; Clampin, M.; Glassman, T.; Guyon, O.; Kasdin, N. J.; Kern, B. D.; Lyon, R.; Mawet, D.; hide

    2013-01-01

    We present and compare experimental results in high contrast imaging representing the state of the art in coronagraph and starshade technology. These experiments have been undertaken with the goal of demonstrating the capability of detecting Earth-like planets around nearby Sun-like stars. The contrast of an Earth seen in reflected light around a Sun-like star would be about 1.2 x 10(exp -10). Several of the current candidate technologies now yield raw contrasts of 1.0 x 10(exp -9) or better, and so should enable the detection of Earths, assuming a gain in sensitivity in post-processing of a factor of 10. We present results of coronagraph and starshade experiments conducted at visible and infrared wavelengths. Cross-sections of dark fields are directly compared as a function of field angle and bandwidth. The strength and differences of the techniques are compared.

  2. Gaussian broad-beam excimer laser: clinical and experimental results.

    PubMed

    Schraepen, P; Eskina, E; Gobin, L; Trau, R; Timmermans, J; Tassignon, M J

    2005-01-01

    To evaluate the mid-term (1-3 years) results of the Gaussian broad-beam excimer laser Delivery System (DS) after single treatment for the correction of myopia. To study the corneal surface with scanning electron microscopy (SEM) after excimer laser ablation using a flying spot delivery system (Bausch & Lomb) and a Gaussian Delivery System (GDS) (InPro). The 1035 consecutive eyes studied were split in four groups with respect to the treated myopia, expressed in spherical equivalent: low myopia up to -3.00 D (183 eyes), moderate myopia from -3.25 D to -6.00 D (540 eyes), high myopia from -6.25 D to -10.00 D (210 eyes) and very high myopia from -10.25 D to -20.00 D (102 eyes). Four post-mortem eyes of two donors were treated using the flying spot DS on one eye and the GDS on the other eye. We achieved postoperative spheriqual equivalent within +/- 1 D of emmetropia in respectively 99.1%, 98.9%, 83% and 21% of the eyes of group 1, 2, 3 and 4. UCVA was 10/10 or better in respectively 65%, 51% and 19% of group 1, 2 and 3. UCVA was 5/10 or better in respectively 86% and 75% of group 3 and 4. The defocus equivalent refraction was 1.0 or less in respectively 98%, 93%, 62%, and 7% of the four groups. On SEM, the corneal surface presented a smooth and polished profile for the GDS. The Gaussian Delivery System gives comparable results to the flying spot laser system for surface laser ablation in myopic eyes up to -10 D. Advantages of this system are: smooth ablation surface, short treatment time, low haze rate, high reliability and easy maintenance of the device due to the optical DS. It is an interesting alternative for the more complex mechanical DS.

  3. Science Achievement of Elementary and Secondary School Students in Japan: The Results of the IEA Study. NIER Occasional Paper 01/89.

    ERIC Educational Resources Information Center

    Miyake, Misao

    This document reports the state of science achievement of Japanese students based on the Second International Science study conducted in 1983-84. Results are compared to the first study conducted in 1970. The target populations, samples, and structure of the second study are described. Test results including score distribution and high and low…

  4. Monetary incentives in support of academic achievement: results of a randomized field trial involving high-achieving, low-resource, ethnically diverse urban adolescents.

    PubMed

    Spencer, Margaret Beale; Noll, Elizabeth; Cassidy, Elaine

    2005-06-01

    Significant resources have been directed at understanding and alleviating the achievement gap in education. Most programs focused on this aim rely on a top-down approach, including funding for infrastructure improvement, curriculum development, class size, and teacher salaries. This article presents findings from a randomized field trial that evaluates a bottom-up approach in which high-achieving students of diverse racial and ethnic backgrounds from poor families are given monetary incentives to maintain their academic standing. The evaluation was designed to explore the role of monetary incentives as a mechanism for promoting resiliency in the face of poverty-related challenge. Discussion of what motivates students to learn is framed as a function of normal cognitive and socioemotional development in challenging environments. Evaluation findings indicate that monetary incentives are effective in promoting academic success to different degrees and for different reasons depending on students' perception of the meaning of the incentive in relation to their emergent identity.

  5. Transport of fluorobenzoate tracers in a vegetated hydrologic control volume: 1. Experimental results

    NASA Astrophysics Data System (ADS)

    Queloz, Pierre; Bertuzzo, Enrico; Carraro, Luca; Botter, Gianluca; Miglietta, Franco; Rao, P. S. C.; Rinaldo, Andrea

    2015-04-01

    This paper reports about the experimental evidence collected on the transport of five fluorobenzoate tracers injected under controlled conditions in a vegetated hydrologic volume, a large lysimeter (fitted with load cells, sampling ports, and an underground chamber) where two willows prompting large evapotranspiration fluxes had been grown. The relevance of the study lies in the direct and indirect measures of the ways in which hydrologic fluxes, in this case, evapotranspiration from the upper surface and discharge from the bottom drainage, sample water and solutes in storage at different times under variable hydrologic forcings. Methods involve the accurate control of hydrologic inputs and outputs and a large number of suitable chemical analyses of water samples in discharge waters. Mass extraction from biomass has also been performed ex post. The results of the 2 year long experiment established that our initial premises on the tracers' behavior, known to be sorption-free under saturated conditions which we verified in column leaching tests, were unsuitable as large differences in mass recovery appeared. Issues on reactivity thus arose and were addressed in the paper, in this case attributed to microbial degradation and solute plant uptake. Our results suggest previously unknown features of fluorobenzoate compounds as hydrologic tracers, potentially interesting for catchment studies owing to their suitability for distinguishable multiple injections, and an outlook on direct experimental closures of mass balance in hydrologic transport volumes involving fluxes that are likely to sample differently stored water and solutes.

  6. College Students' Achievement and Understanding of Experimental and Theoretical Probability: The Role of Tasks

    ERIC Educational Resources Information Center

    Papaieronymou, Irini

    2012-01-01

    This study examined the role of particular tasks implemented through two instructional methods on college students' "achievement" and understanding of probability. A mixed methods design that utilized a pre-test and post-test was used. This included treatment and control groups, each comprised of students in three sections of an…

  7. The effect of social and token economy reinforcements on academic achievement of students with intellectual disabilities.

    PubMed

    Mirzamani, S Mahmood; Ashoori, Mohammad; Sereshki, Narges Adib

    2011-01-01

    This study investigates the effect of social and token economy reinforcements on academic achievement of 9th grade boy students with intellectual disabilities in an experimental science class in Tehran Province. The method used for this study was experimental by pre-test, post- test with a control group. The boy students with intellectual disabilities from three junior high schools participated in this study. The sample consisted of thirty, 9th grade boy students with intellectual disabilities in the selected schools; the schools were chosen by the multi-stage cluster method. To measure the progress of students in the science class, a teacher made test and the Wechsler intelligence test for matching the groups for IQ were used. To ensure validity, the content validity criteria depended tests calculated by the Lashe method and teachers' perspective were used. The reliability coefficient was obtained by the reliability coefficient of related tests; the percent agreement method and the obtained data were analyzed using one-way variance analysis and Shefe prosecution test. The results showed that there was a significant increase in academic achievement of students with intellectual disabilities when using token economy than using social reinforcements compared with the control group. Also, when using social reinforcements, the academic achievement of students was more than the control group. Token economy and social reinforcements increased the academic achievement of students with intellectual disabilities in the science class; and also the effect of token economy reinforcements was more than social reinforcements on the subjects.

  8. Flight Measurements of Helicopter Blade Motion with a Comparison between Theoretical and Experimental Results

    DTIC Science & Technology

    1947-04-01

    EXPERS5EHTAL RESULTS By G-arry C. Myers, Jr. STHMÄRY Hi order to provide " basic data on helicopter rotor-"blade motion, photographic .records of...ABOUT 2HE AXIS OF NO FEATHERING Reason for conversion.- At the time that the " basic theoretical treatments, such as that of reference 1, were made...of the machanical means used for achieving it. This fact may be confirmed by inspection but has also been demonstrated mathematically in reference

  9. Microfabricated Air-Microfluidic Sensor for Personal Monitoring of Airborne Particulate Matter: Design, Fabrication, and Experimental Results

    EPA Science Inventory

    We present the design and fabrication of a micro electro mechanical systems (MEMS) air-microfluidic particulate matter (PM) sensor, and show experimental results obtained from exposing the sensor to concentrations of tobacco smoke and diesel exhaust, two commonly occurring P...

  10. "Earth, Sun and Moon": Computer Assisted Instruction in Secondary School Science--Achievement and Attitudes

    ERIC Educational Resources Information Center

    Ercan, Orhan; Bilen, Kadir; Ural, Evrim

    2016-01-01

    This study investigated the impact of a web-based teaching method on students' academic achievement and attitudes in the elementary education fifth grade Science and Technology unit, "System of Earth, Sun and Moon". The study was a quasi-experimental study with experimental and control groups comprising 54 fifth grade students attending…

  11. Low cost solar array project: Experimental process system development unit for producing semiconductor-grade silicon using the silane-to-silicon process

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The results of the free space reactor experimental work are summarized. Overall, the objectives were achieved and the unit can be confidently scaled to the EPSDU size based on the experimental work and supporting theoretical analyses. The piping and instrumentation of the fluidized bed reactor was completed.

  12. Axial pico turbine - construction and experimental research

    NASA Astrophysics Data System (ADS)

    Peczkis, G.; Goryca, Z.; Korczak, A.

    2017-08-01

    The paper concerns axial water turbine of power equal to 1 kW. The example of axial water turbine constructional calculations was provided, as well as turbine rotor construction with NACA profile blades. The laboratory test rig designed and built to perform measurements on pico turbine was described. The turbine drove three-phase electrical generator. On the basis of highest efficiency parameters, pico turbine basic characteristics were elaborated. The experimental research results indicated that pico turbine can achieve maximum efficiency close to the values of larger water turbines.

  13. Experimental Results for an Acoustic Driver for MTF

    NASA Astrophysics Data System (ADS)

    Laberge, Michel

    2009-06-01

    General Fusion is planning to form an FRC or spheromak of 1017 cm-3, 100 eV, 40 cm diameter by merging two spheromaks with reverse or co-helicity. This target will be further compressed in a 3 m diameter tank filled with liquid PbLi with the plasma in the center. The tank is surrounded with pneumatically powered impact pistons that will send a convergent shock wave in the liquid to compress the plasma to 1020 cm-3, 10 keV, 4 cm diameter for 7 μs. General Fusion has built a 500 kJ, 80 μs, 6 GW pneumatic impact piston capable of developing 2 GPa (300 kpsi). In this paper we will present the performances achieved to date.

  14. Simple and fast polydimethylsiloxane (PDMS) patterning using a cutting plotter and vinyl adhesives to achieve etching results.

    PubMed

    Hyun Kim; Sun-Young Yoo; Ji Sung Kim; Zihuan Wang; Woon Hee Lee; Kyo-In Koo; Jong-Mo Seo; Dong-Il Cho

    2017-07-01

    Inhibition of polydimethylsiloxane (PDMS) polymerization could be observed when spin-coated over vinyl substrates. The degree of polymerization, partially curing or fully curing, depended on the PDMS thickness coated over the vinyl substrate. This characteristic was exploited to achieve simple and fast PDMS patterning method using a vinyl adhesive layer patterned through a cutting plotter. The proposed patterning method showed results resembling PDMS etching. Therefore, patterning PDMS over PDMS, glass, silicon, and gold substrates were tested to compare the results with conventional etching methods. Vinyl stencils with widths ranging from 200μm to 1500μm were used for the procedure. To evaluate the accuracy of the cutting plotter, stencil designed on the AutoCAD software and the actual stencil widths were compared. Furthermore, this method's accuracy was also evaluated by comparing the widths of the actual stencils and etched PDMS results.

  15. The Influence of Building Block Play on Mathematics Achievement and Logical and Divergent Thinking in Italian Primary School Mathematics Classes

    ERIC Educational Resources Information Center

    Pirrone, Concetta; Tienken, Christopher H.; Pagano, Tatiana; Di Nuovo, Santo

    2018-01-01

    In an experimental study to explain the effect of structured Building Block Play with LEGO™ bricks on 6-year-old student mathematics achievement and in the areas of logical thinking, divergent thinking, nonverbal reasoning, and mental imagery, students in the experimental group scored significantly higher (p = 0.05) in mathematics achievement and…

  16. Student Achievement in Edison Schools: Mixed Results in an Ongoing Enterprise. Research Report.

    ERIC Educational Resources Information Center

    American Federation of Teachers, Washington, DC.

    A study examined student achievement in selected Edison schools through an analysis of test-score data. To qualify for the study, each school had to be in operation for more than 1 year and had to have solid student testing data from a solid evaluation design. Eight schools were selected, and their reading data were compared with those of…

  17. First-Generation College Student Achievement and the First-Year Seminar: A Quasi-Experimental Design

    ERIC Educational Resources Information Center

    Vaughan, Angela; Parra, Janessa; Lalonde, Trent

    2014-01-01

    Research has shown consistently that first-generation college students are less prepared academically for college, have a higher risk for dropping out, and are less likely to obtain a degree. This study investigated the effect of first-generation students' participation in a first-year seminar (FYS) on academic achievement and persistence to the…

  18. On Money and Motivation: A Quasi-Experimental Analysis of Financial Incentives for College Achievement

    ERIC Educational Resources Information Center

    Scott-Clayton, Judith

    2011-01-01

    Programs linking college aid to academic achievement could work either by lowering the cost of college or by inducing additional student effort. I examine the PROMISE program in West Virginia, which offers free tuition to students who maintain a minimum GPA and course load. Using administrative data, I exploit discontinuities in the eligibility…

  19. Comparison of Computational and Experimental Microphone Array Results for an 18%-Scale Aircraft Model

    NASA Technical Reports Server (NTRS)

    Lockard, David P.; Humphreys, William M.; Khorrami, Mehdi R.; Fares, Ehab; Casalino, Damiano; Ravetta, Patricio A.

    2015-01-01

    An 18%-scale, semi-span model is used as a platform for examining the efficacy of microphone array processing using synthetic data from numerical simulations. Two hybrid RANS/LES codes coupled with Ffowcs Williams-Hawkings solvers are used to calculate 97 microphone signals at the locations of an array employed in the NASA LaRC 14x22 tunnel. Conventional, DAMAS, and CLEAN-SC array processing is applied in an identical fashion to the experimental and computational results for three different configurations involving deploying and retracting the main landing gear and a part span flap. Despite the short time records of the numerical signals, the beamform maps are able to isolate the noise sources, and the appearance of the DAMAS synthetic array maps is generally better than those from the experimental data. The experimental CLEAN-SC maps are similar in quality to those from the simulations indicating that CLEAN-SC may have less sensitivity to background noise. The spectrum obtained from DAMAS processing of synthetic array data is nearly identical to the spectrum of the center microphone of the array, indicating that for this problem array processing of synthetic data does not improve spectral comparisons with experiment. However, the beamform maps do provide an additional means of comparison that can reveal differences that cannot be ascertained from spectra alone.

  20. Experimental quantum forgery of quantum optical money

    NASA Astrophysics Data System (ADS)

    Bartkiewicz, Karol; Černoch, Antonín; Chimczak, Grzegorz; Lemr, Karel; Miranowicz, Adam; Nori, Franco

    2017-03-01

    Unknown quantum information cannot be perfectly copied (cloned). This statement is the bedrock of quantum technologies and quantum cryptography, including the seminal scheme of Wiesner's quantum money, which was the first quantum-cryptographic proposal. Surprisingly, to our knowledge, quantum money has not been tested experimentally yet. Here, we experimentally revisit the Wiesner idea, assuming a banknote to be an image encoded in the polarization states of single photons. We demonstrate that it is possible to use quantum states to prepare a banknote that cannot be ideally copied without making the owner aware of only unauthorized actions. We provide the security conditions for quantum money by investigating the physically-achievable limits on the fidelity of 1-to-2 copying of arbitrary sequences of qubits. These results can be applied as a security measure in quantum digital right management.

  1. Achieving high energy absorption capacity in cellular bulk metallic glasses

    PubMed Central

    Chen, S. H.; Chan, K. C.; Wu, F. F.; Xia, L.

    2015-01-01

    Cellular bulk metallic glasses (BMGs) have exhibited excellent energy-absorption performance by inheriting superior strength from the parent BMGs. However, how to achieve high energy absorption capacity in cellular BMGs is vital but mysterious. In this work, using step-by-step observations of the deformation evolution of a series of cellular BMGs, the underlying mechanisms for the remarkable energy absorption capacity have been investigated by studying two influencing key factors: the peak stress and the decay of the peak stress during the plastic-flow plateau stages. An analytical model of the peak stress has been proposed, and the predicted results agree well with the experimental data. The decay of the peak stress has been attributed to the geometry change of the macroscopic cells, the formation of shear bands in the middle of the struts, and the “work-softening” nature of BMGs. The influencing factors such as the effect of the strut thickness and the number of unit cells have also been investigated and discussed. Strategies for achieving higher energy absorption capacity in cellular BMGs have been proposed. PMID:25973781

  2. The experimental results of AMTEC and a study of its terrestrial applications in IEE of China

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ni, Q.; Tong, J.; Kan, Y.

    1997-12-31

    The R and D activities in the field of AMTEC research at The Institute of Electrical Engineering, Chinese Academy of Sciences are introduced. The outline of experimental facility with a single tube cell is described. The experimental results so far are reported followed by an analysis of electrical characteristic, in particular, an evaluation of characteristic of BASE/porous electrode interface with the effective sheet resistivity and the electrode efficiency. The approaches for improving device performance are discussed. The terrestrial applications of AMTEC in China are considered as an alternative of conventional diesel-generators. The possibility of AMTEC power supply for some separatemore » sites is predicted.« less

  3. An Investigation of the Effectiveness of Increasing Academic Learning Time for College Undergraduate Students' Achievement in Kuwait

    ERIC Educational Resources Information Center

    Al-Shammari, Zaid; Mohammad, Anwar; Al-Shammari, Bandar

    2010-01-01

    The study investigated the effectiveness of increasing ALT for college students' achievement in Kuwait. In Phase 1, 37 students participated (22, experimental; 15, control); in Phase 2, 19 students participated (8, sub-experimental; 11, sub-control). Several experimental research methods used in conducting this study, including development of a…

  4. Secondary emission from dust grains: Comparison of experimental and model results

    NASA Astrophysics Data System (ADS)

    Richterova, I.; Pavlu, J.; Nemecek, Z.; Safrankova, J.; Zilavy, P.

    The motion, coalescence, and other processes in dust clouds are determined by the dust charge. Since dust grains in the space are bombarded by energetic electrons, the secondary emission is an important process contributing to their charge. It is generally expected that the secondary emission yield is related to surface properties of the bombarded body. However, it is well known that secondary emission from small bodies is determined not only by their composition but an effect of dimension can be very important when the penetration depth of primary electrons is comparable with the grain size. It implies that the secondary emission yield can be influenced by the substrate material if the surface layer is thin enough. We have developed a simple Monte Carlo model of secondary emission that was successfully applied on the dust simulants from glass and melanine formaldehyd (MF) resin and matched very well experimental results. In order to check the influence of surface layers, we have modified the model for spheres covered by a layer with different material properties. The results of model simulations are compared with measurements on MF spheres covered by different metals.

  5. Experimental investigation of extended Kalman Filter combined with carrier phase recovery for 16-QAM system

    NASA Astrophysics Data System (ADS)

    Shu, Tong; Li, Yan; Yu, Miao; Zhang, Yifan; Zhou, Honghang; Qiu, Jifang; Guo, Hongxiang; Hong, Xiaobin; Wu, Jian

    2018-02-01

    Performance of Extended Kalman Filter combined with the Viterbi-Viterbi phase estimation (VVPE-EKF) for joint phase noise mitigation and amplitude noise equalization is experimental demonstrated. Experimental results show that, for 11.2 Gbaud SP-16-QAM, the proposed VVPE-EKF achieves 0.9 dB required OSNR reduction at bit error ratio (BER) of 3.8e-3 compared to the VVPE. The result of maximum likelihood combined with VVPE (VVPE-ML) is only 0.3 dB. For 28 GBaud SP-16-QAM signal, VVPE-EKF achieves 3 dB required OSNR reduction at BER=3.8e-3 (7% HD-FEC threshold) compared to VVPE. And VVPE-ML can reduce the required OSNR for 1.7 dB compared to the VVPE. VVPE-EKF outperforms DD-EKF 3.7 dB and 0.7 dB for 11.2 GBaud and 28 GBaud system, respectively.

  6. Experimental Aerodynamic Characteristics of the Pegasus Air-Launched Booster and Comparisons with Predicted and Flight Results

    NASA Technical Reports Server (NTRS)

    Rhode, M. N.; Engelund, Walter C.; Mendenhall, Michael R.

    1995-01-01

    Experimental longitudinal and lateral-directional aerodynamic characteristics were obtained for the Pegasus and Pegasus XL configurations over a Mach number range from 1.6 to 6 and angles of attack from -4 to +24 degrees. Angle of sideslip was varied from -6 to +6 degrees, and control surfaces were deflected to obtain elevon, aileron, and rudder effectiveness. Experimental data for the Pegasus configuration are compared with engineering code predictions performed by Nielsen Engineering & Research, Inc. (NEAR) in the aerodynamic design of the Pegasus vehicle, and with results from the Aerodynamic Preliminary Analysis System (APAS) code. Comparisons of experimental results are also made with longitudinal flight data from Flight #2 of the Pegasus vehicle. Results show that the longitudinal aerodynamic characteristics of the Pegasus and Pegasus XL configurations are similar, having the same lift-curve slope and drag levels across the Mach number range. Both configurations are longitudinally stable, with stability decreasing towards neutral levels as Mach number increases. Directional stability is negative at moderate to high angles of attack due to separated flow over the vertical tail. Dihedral effect is positive for both configurations, but is reduced 30-50 percent for the Pegasus XL configuration because of the horizontal tail anhedral. Predicted longitudinal characteristics and both longitudinal and lateral-directional control effectiveness are generally in good agreement with experiment. Due to the complex leeside flowfield, lateral-directional characteristics are not as well predicted by the engineering codes. Experiment and flight data are in good agreement across the Mach number range.

  7. Effectiveness of Blended Teaching Strategy on the Achievement of Third Grade Students in Mathematics

    ERIC Educational Resources Information Center

    Yaghmour, Kholoud Subhi

    2016-01-01

    The study aimed to investigate the Blended Education strategy in the achievement of the third grade students in mathematics. The study sample consisted of (97) male and female students distributed on four classes: (47) male and female students in the experimental group and (50) male and female students in the control group. To achieve the…

  8. Achievement Goals and Achievement Emotions: A Meta-Analysis

    ERIC Educational Resources Information Center

    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…

  9. Primary experimental results of wire-array Z-pinches on PTS

    NASA Astrophysics Data System (ADS)

    Huang, X. B.; Zhou, S. T.; Ren, X. D.; Dan, J. K.; Wang, K. L.; Zhang, S. Q.; Li, J.; Xu, Q.; Cai, H. C.; Duan, S. C.; Ouyang, K.; Chen, G. H.; Ji, C.; Wang, M.; Feng, S. P.; Yang, L. B.; Xie, W. P.; Deng, J. J.

    2014-12-01

    The Primary Test Stand (PTS) developed at the China Academy of Engineering Physics is a multiterawatt pulsed power driver, which can deliver a ˜10 MA, 70 ns rise-time (10%-90%) current to a short circuit load and has important applications in Z-pinch driven inertial confinement fusion and high energy density physics. In this paper, primary results of tungsten wire-array Z-pinch experiments on PTS are presented. The load geometries investigated include 15-mm-tall cylindrical single and nested arrays with diameter ranging from 14.4-26.4 mm, and consisting of 132˜276 tungsten wires with 5˜10 μm in diameter. Multiple diagnostics were fielded to determine the characteristics of x-ray radiations and to obtain self-emitting images of imploding plasmas. X-ray power up to 80 TW with ˜3 ns FWMH is achieved by using nested wire arrays. The total x-ray energy exceeds 500 kJ and the peak radiation temperature is about 150 eV. Typical velocity of imploding plasmas goes around 3˜5×107 cm/s and the radial convergence ratio is between 10 and 20.

  10. Overview of Recent DIII-D Experimental Results

    NASA Astrophysics Data System (ADS)

    Fenstermacher, Max; DIII-D Team

    2017-10-01

    Recent DIII-D experiments contributed to the ITER physics basis and to physics understanding for extrapolation to future devices. A predict-first analysis showed how shape can enhance access to RMP ELM suppression. 3D equilibrium changes from ELM control RMPs, were linked to density pumpout. Ion velocity imaging in the SOL showed 3D C2+flow perturbations near RMP induced n =1 islands. Correlation ECE reveals a 40% increase in Te turbulence during QH-mode and 70% during RMP ELM suppression vs. ELMing H-mode. A long-lived predator-prey oscillation replaces edge MHD in recent low-torque QH-mode plasmas. Spatio-temporally resolved runaway electron measurements validate the importance of synchrotron and collisional damping on RE dissipation. A new small angle slot divertor achieves strong plasma cooling and facilitates detachment access. Fast ion confinement was improved in high q_min scenarios using variable beam energy optimization. First reproducible, stable ITER baseline scenarios were established. Studies have validated a model for edge momentum transport that predicts the pedestal main-ion intrinsic velocity value and direction. Work supported by the US DOE under DE-FC02-04ER54698 and DE-AC52-07NA27344.

  11. The Effect of Problem-Solving Instruction on the Programming Self-efficacy and Achievement of Introductory Computer Science Students

    NASA Astrophysics Data System (ADS)

    Maddrey, Elizabeth

    Research in academia and industry continues to identify a decline in enrollment in computer science. One major component of this decline in enrollment is a shortage of female students. The primary reasons for the gender gap presented in the research include lack of computer experience prior to their first year in college, misconceptions about the field, negative cultural stereotypes, lack of female mentors and role models, subtle discriminations in the classroom, and lack of self-confidence (Pollock, McCoy, Carberry, Hundigopal, & You, 2004). Male students are also leaving the field due to misconceptions about the field, negative cultural stereotypes, and a lack of self-confidence. Analysis of first year attrition revealed that one of the major challenges faced by students of both genders is a lack of problem-solving skills (Beaubouef, Lucas & Howatt, 2001; Olsen, 2005; Paxton & Mumey, 2001). The purpose of this study was to investigate whether specific, non-mathematical problem-solving instruction as part of introductory programming courses significantly increased computer programming self-efficacy and achievement of students. The results of this study showed that students in the experimental group had significantly higher achievement than students in the control group. While this shows statistical significance, due to the effect size and disordinal nature of the data between groups, care has to be taken in its interpretation. The study did not show significantly higher programming self-efficacy among the experimental students. There was not enough data collected to statistically analyze the effect of the treatment on self-efficacy and achievement by gender. However, differences in means were observed between the gender groups, with females in the experimental group demonstrating a higher than average degree of self-efficacy when compared with males in the experimental group and both genders in the control group. These results suggest that the treatment from this

  12. Achieving Benchmark Results for Neonatal Palliation of Hypoplastic Left Heart Syndrome and Related Anomalies in an Emerging Program.

    PubMed

    Dodge-Khatami, Ali; Chancellor, William Z; Gupta, Bhawna; Seals, Samantha R; Ebeid, Makram R; Batlivala, Sarosh P; Taylor, Mary B; Salazar, Jorge D

    2015-07-01

    Results of surgical management of hypoplastic left heart syndrome (HLHS) and related anomalies are often compared to published benchmark data which reflect the use of a variety of surgical and hybrid protocols. We report encouraging results achieved in an emerging program, despite a learning curve at all care levels. Rather than relying on a single preferred protocol, surgical management was based on matching surgical strategy to individual patient factors. From 2010 to 2014, a total of 47 consecutive patients with HLHS or related anomalies with ductal-dependent systemic circulation underwent initial surgical palliation, including 30 Norwood stage I, 8 hybrid stage I, and 9 salvage-to-Norwood procedures. True hybrid procedures entailed bilateral pulmonary artery banding and ductal stenting. In the salvage-to-Norwood strategy, ductal stenting was withheld in favor of continued prostaglandin infusion in anticipation of a deferred Norwood procedure. Cardiac comorbidities (obstructed pulmonary venous return, poor ventricular function, and atrioventricular valve regurgitation) and noncardiac comorbidities influenced the choice of treatment strategies and were analyzed as potential risk factors for extracorporeal membrane oxygenation (ECMO) support or in-hospital mortality. Overall hospital survival was 81% (Norwood 83.3%, hybrid 88%, "salvage" 67%; P = .4942). Extracorporeal membrane oxygenation support was used for eight (17%) patients with two survivors. For cases with obstructed pulmonary venous return (n = 10, 21%), management choices favored a hybrid or salvage strategy (P = .0026). Aortic atresia (n = 22, 47%) was treated by a Norwood or salvage-to-Norwood. No cardiac, noncardiac, or genetic comorbidities were identified as independent risk factors for ECMO or discharge mortality in a multivariable analysis. Our emerging program achieved outcomes that compare favorably to published benchmark data with respect to hospital survival. These results reflect rigorous

  13. Shuttle Damage/Repair from the Perspective of Hypersonic Boundary Layer Transition - Experimental Results

    NASA Technical Reports Server (NTRS)

    Horvath, Thomas J.; Berry, Scott A.; Merski, N. Ronald; Berger, Karen T.; Buck, Gregory M.; Liechty, Derek S.; Schneider, Steven P.

    2006-01-01

    An overview is provided of the experimental wind tunnel program conducted at the NASA Langley Research Center Aerothermodynamics Laboratory in support of an agency-wide effort to prepare the Shuttle Orbiter for Return-to-Flight. The effect of an isolated protuberance and an isolated rectangular cavity on hypersonic boundary layer transition onset on the windward surface of the Shuttle Orbiter has been experimentally characterized. These experimental studies were initiated to provide a protuberance and cavity effects database for developing hypersonic transition criteria to support on-orbit disposition of thermal protection system damage or repair. In addition, a synergistic experimental investigation was undertaken to assess the impact of an isolated mass-flow entrainment source (simulating pyrolysis/outgassing from a proposed tile repair material) on boundary layer transition. A brief review of the relevant literature regarding hypersonic boundary layer transition induced from cavities and localized mass addition from ablation is presented. Boundary layer transition results were obtained using 0.0075-scale Orbiter models with simulated tile damage (rectangular cavities) of varying length, width, and depth and simulated tile damage or repair (protuberances) of varying height. Cavity and mass addition effects were assessed at a fixed location (x/L = 0.3) along the model centerline in a region of near zero pressure gradient. Cavity length-to-depth ratio was systematically varied from 2.5 to 17.7 and length-to-width ratio of 1 to 8.5. Cavity depth-to-local boundary layer thickness ranged from 0.5 to 4.8. Protuberances were located at several sites along the centerline and port/starboard attachment lines along the chine and wing leading edge. Protuberance height-to-boundary layer thickness was varied from approximately 0.2 to 1.1. Global heat transfer images and heating distributions of the Orbiter windward surface using phosphor thermography were used to infer the

  14. Physico-chemical properties of aqueous drug solutions: From the basic thermodynamics to the advanced experimental and simulation results.

    PubMed

    Bellich, Barbara; Gamini, Amelia; Brady, John W; Cesàro, Attilio

    2018-04-05

    The physical chemical properties of aqueous solutions of model compounds are illustrated in relation to hydration and solubility issues by using three perspectives: thermodynamic, spectroscopic and molecular dynamics simulations. The thermodynamic survey of the fundamental backgrounds of concentration dependence and experimental solubility results show some peculiar behavior of aqueous solutions with several types of similar solutes. Secondly, the use of a variety of experimental spectroscopic devices, operating under different experimental conditions of dimension and frequency, has produced a large amount of structural and dynamic data on aqueous solutions showing the richness of the information produced, depending on where and how the experiment is carried out. Finally, the use of molecular dynamics computational work is presented to highlight how the different types of solute functional groups and surface topologies organize adjacent water molecules differently. The highly valuable contribution of computer simulation studies in providing molecular explanations for experimental deductions, either of a thermodynamic or spectroscopic nature, is shown to have changed the current knowledge of many aqueous solution processes. While this paper is intended to provide a collective view on the latest literature results, still the presentation aims at a tutorial explanation of the potentials of the three methodologies in the field of aqueous solutions of pharmaceutical molecules. Copyright © 2018. Published by Elsevier B.V.

  15. Experimental Infections of Wild Birds with West Nile Virus

    PubMed Central

    Pérez-Ramírez, Elisa; Llorente, Francisco; Jiménez-Clavero, Miguel Ángel

    2014-01-01

    Avian models of West Nile virus (WNV) disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental research that needs to be conducted in biosecurity level 3 (BSL3) facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas. PMID:24531334

  16. Effects of Activity Based Blended Learning Strategy on Prospective of Teachers' Achievement and Motivation

    ERIC Educational Resources Information Center

    Abdelraheem, Ahmed Yousif; Ahmed, Abdelrahman Mohammed

    2015-01-01

    The study investigates the effect of Activity based Blended Learning strategy and Conventional Blended Learning strategy on students' achievement and motivation. Two groups namely, experimental and control group from Sultan Qaboos University were selected randomly for the study. To assess students' achievement in the different groups, pre- and…

  17. The Effect of Interactive e-Book on Students' Achievement at Najran University in Computer in Education Course

    ERIC Educational Resources Information Center

    Ebied, Mohammed Mohammed Ahmed; Rahman, Shimaa Ahmed Abdul

    2015-01-01

    The current study aims to examine the effect of interactive e-books on students' achievement at Najran University in computer in education course. Quasi-experimental study design is used in the study and to collect data the researchers built achievement test to measure the dependent variable represented in the achievement affected by experimental…

  18. Instructional Coaching at Selected Middle Schools in South Texas and Effects on Student Achievement

    ERIC Educational Resources Information Center

    Garcia, SantaPaula Gama; Jones, Don; Holland, Glenda; Mundy, Marie-Anne

    2013-01-01

    The purpose of this study was to compare two middle schools in one school district in south Texas to determine if presence or absence of instructional coaches has an effect on student achievement. The research design was a quantitative pre experimental study: a nonequivalent (posttest only) control group design in which the experimental group and…

  19. Participation of Bell Telephone Laboratories in Project Echo and Experimental Results

    NASA Technical Reports Server (NTRS)

    Jakes, William C., Jr.

    1961-01-01

    On August 12, 1960, Echo I, a 100-foot-diameter spherical balloon, was placed in orbit around the earth by the National Aeronautics and Space Administration. The objective was to demonstrate the feasibility of long-distance communication by microwave reflection from a satellite. A two-way coast-to-coast voice circuit was to be established between the Jet Propulsion Laboratory (JPL) facility in California and a station provided by Bell Telephone Laboratories (STL) in New Jersey. Similar tests were also planned with the Naval Research Laboratory and other stations. This paper describes the general organization and operation of the Holmdel, New Jersey, station, and discusses the results of the experiments performed between the balloon launching and March 1, 1961. Successful voice communication was achieved through a variety of modulation methods including frequency modulation with feedback, amplitude modulation, single-sideband modulation, and narrow-band phase modulation. Careful measurements were also made of the loss in the transmission path.

  20. Analysis of attitude and achievement using the 5E instructional model in an interactive television environment

    NASA Astrophysics Data System (ADS)

    Cherry, Gamaliel R.

    The purpose of this quasi-experimental study was to examine attitude and achievement among fifth grade students participating in inquiry and lecture-based forms of instruction through interactive television. Participants (N = 260) were drawn from registered users of NASA's Digital Learning Network(TM). The first three levels of Bloom's Revised Taxonomy were used to measure levels of achievement while the Science Attitude Inventory II was used to measure science attitudes. Results indicated a significant interaction between inquiry and topic area, as well as achievement for remember, understand, and apply levels of Bloom's Revised Taxonomy. Differences between mean scores were in favor of the treatment group on both topic and achievement levels. Findings echo research that encourages the use of inquiry-based instruction to improve achievement. This study also serves as a reference for supplemental content providers searching for an effective instructional strategy when delivering instruction through interactive television. Recommendations for future research include the examination of: development time between inquiry-based and lecture-based strategies, a longitudinal study of attitude and achievement from elementary through middle school, differences between interactive television sessions and asynchronous sessions, and types of inquiry-based instruction related to student achievement and retention through interactive television.

  1. The Effects of Grouping Practices and Curricular Adjustments on Achievement

    ERIC Educational Resources Information Center

    Tieso, Carol

    2005-01-01

    The purpose of this study was to examine the effects of curricular (textbook, revised, and differentiated) and grouping (whole, between, and within-class) practices on intermediate students' achievement in mathematics. A pretest-posttest, quasi-experimental design using a stratified random sample of 31 teachers and their students (N = 645) was…

  2. Experimental Machine Learning of Quantum States

    NASA Astrophysics Data System (ADS)

    Gao, Jun; Qiao, Lu-Feng; Jiao, Zhi-Qiang; Ma, Yue-Chi; Hu, Cheng-Qiu; Ren, Ruo-Jing; Yang, Ai-Lin; Tang, Hao; Yung, Man-Hong; Jin, Xian-Min

    2018-06-01

    Quantum information technologies provide promising applications in communication and computation, while machine learning has become a powerful technique for extracting meaningful structures in "big data." A crossover between quantum information and machine learning represents a new interdisciplinary area stimulating progress in both fields. Traditionally, a quantum state is characterized by quantum-state tomography, which is a resource-consuming process when scaled up. Here we experimentally demonstrate a machine-learning approach to construct a quantum-state classifier for identifying the separability of quantum states. We show that it is possible to experimentally train an artificial neural network to efficiently learn and classify quantum states, without the need of obtaining the full information of the states. We also show how adding a hidden layer of neurons to the neural network can significantly boost the performance of the state classifier. These results shed new light on how classification of quantum states can be achieved with limited resources, and represent a step towards machine-learning-based applications in quantum information processing.

  3. Nebraska STARS: Achieving Results

    ERIC Educational Resources Information Center

    Roschewski, Pat; Isernhagen, Jody; Dappen, Leon

    2006-01-01

    In 2000, the state of Nebraska passed legislation requiring the assessment of student performance on content standards, but its requirements were very different from those of any other state. Nebraska created what has come to be known as STARS (School-based Teacher-led Assessment and Reporting System). Under STARS, each of Nebraska's nearly 500…

  4. School Context and Educational Outcomes: Results from a Quasi-Experimental Study

    PubMed Central

    Casciano, Rebecca; Massey, Douglas S.

    2013-01-01

    In this study we draw on data from a quasi-experimental study to test whether moving into a subsidized housing development in an affluent suburb yields educational benefits to the children of residents, compared to the educations they would have received had they not moved into the development. Results suggest that resident children experienced a significant improvement in school quality compared with a comparison group of students whose parents also had applied for residence. Parents who were residents of the development also displayed higher levels of school involvement compared with the comparison group of non-resident parents, and their children were exposed to significantly lower levels of school disorder and violence within school and spent more time reading outside of school. Living in the development did not influence GPA directly, but did indirectly increase GPA by increasing the time residents spent reading outside of school. PMID:25342878

  5. An experimental study of stratospheric gravity waves - Design and preliminary results

    NASA Astrophysics Data System (ADS)

    Talagrand, O.; Ovarlez, H.

    1984-02-01

    The design of balloon-borne experimental apparatus for long-term gravitational-wave measurements in the stratosphere is reported, and preliminary results of a first test flight are presented. Two gondolas (each containing a pressure sensor; a temperature sensor; horizontal and vertical sonic anemometers; a fin equipped with crossed magnetometers; and data-processing, data-transmission, and control electronics) are suspended 100 and 300 m below a solar/terrestrial-IR-absorption-heated hot-air balloon drifting between altitudes 22 km (night) and 28 km (day); power is supplied by NiCd batteries recharged by solar cells. The path of the first flight, a circumnavigation beginning in Pretoria, South Africa and crossing South America and northern Australia, from December 11, 1982, to February 2, 1983 (when transmission ceased over southern Africa) is shown on a map, and sample data for a 36-h period are summarized in a graph.

  6. Parental Involvement and Academic Achievement

    ERIC Educational Resources Information Center

    Goodwin, Sarah Christine

    2015-01-01

    This research study examined the correlation between student achievement and parent's perceptions of their involvement in their child's schooling. Parent participants completed the Parent Involvement Project Parent Questionnaire. Results slightly indicated parents of students with higher level of achievement perceived less demand or invitations…

  7. Early Results in Capella's Prior Learning Assessment Experimental Site Initiative

    ERIC Educational Resources Information Center

    Klein, Jillian

    2017-01-01

    In July 2014, the U.S. Department of Education announced a new round of experimental sites focusing on competency-based education. Capella University was selected to participate in three of the Department of Education's competency-based education (CBE) experiments and began by implementing the prior learning assessment experiment, which allows…

  8. A Robust Adaptive Autonomous Approach to Optimal Experimental Design

    NASA Astrophysics Data System (ADS)

    Gu, Hairong

    Experimentation is the fundamental tool of scientific inquiries to understand the laws governing the nature and human behaviors. Many complex real-world experimental scenarios, particularly in quest of prediction accuracy, often encounter difficulties to conduct experiments using an existing experimental procedure for the following two reasons. First, the existing experimental procedures require a parametric model to serve as the proxy of the latent data structure or data-generating mechanism at the beginning of an experiment. However, for those experimental scenarios of concern, a sound model is often unavailable before an experiment. Second, those experimental scenarios usually contain a large number of design variables, which potentially leads to a lengthy and costly data collection cycle. Incompetently, the existing experimental procedures are unable to optimize large-scale experiments so as to minimize the experimental length and cost. Facing the two challenges in those experimental scenarios, the aim of the present study is to develop a new experimental procedure that allows an experiment to be conducted without the assumption of a parametric model while still achieving satisfactory prediction, and performs optimization of experimental designs to improve the efficiency of an experiment. The new experimental procedure developed in the present study is named robust adaptive autonomous system (RAAS). RAAS is a procedure for sequential experiments composed of multiple experimental trials, which performs function estimation, variable selection, reverse prediction and design optimization on each trial. Directly addressing the challenges in those experimental scenarios of concern, function estimation and variable selection are performed by data-driven modeling methods to generate a predictive model from data collected during the course of an experiment, thus exempting the requirement of a parametric model at the beginning of an experiment; design optimization is

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

    PubMed

    Hart, William; Albarracín, Dolores

    2009-12-01

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

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

    PubMed Central

    Hart, William; Albarracín, Dolores

    2013-01-01

    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 fun. Findings indicated that achievement priming (vs. control priming) activated a goal to achieve and inhibited a goal to have fun in individuals with chronically high-achievement motivation but activated a goal to have fun and inhibited a goal to achieve in individuals with chronically low-achievement motivation. PMID:19968423

  11. Dynamics of the brain: Mathematical models and non-invasive experimental studies

    NASA Astrophysics Data System (ADS)

    Toronov, V.; Myllylä, T.; Kiviniemi, V.; Tuchin, V. V.

    2013-10-01

    Dynamics is an essential aspect of the brain function. In this article we review theoretical models of neural and haemodynamic processes in the human brain and experimental non-invasive techniques developed to study brain functions and to measure dynamic characteristics, such as neurodynamics, neurovascular coupling, haemodynamic changes due to brain activity and autoregulation, and cerebral metabolic rate of oxygen. We focus on emerging theoretical biophysical models and experimental functional neuroimaging results, obtained mostly by functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS). We also included our current results on the effects of blood pressure variations on cerebral haemodynamics and simultaneous measurements of fast processes in the brain by near-infrared spectroscopy and a very novel functional MRI technique called magnetic resonance encephalography. Based on a rapid progress in theoretical and experimental techniques and due to the growing computational capacities and combined use of rapidly improving and emerging neuroimaging techniques we anticipate during next decade great achievements in the overall knowledge of the human brain.

  12. Mathematics beliefs and achievement of elementary school students in Japan and the United States: results from the Third International Mathematics and Science Study.

    PubMed

    House, J Daniel

    2006-03-01

    Student self-beliefs are significantly related to several types of academic achievement. In addition, results from international assessments have indicated that students in Japan have typically scored above international averages (D. L. Kelly, I. V. S. Mullis, & M. O. Martin, 2000). In this study, the author examined relationships between mathematics beliefs and achievement of elementary school-aged students in the United States and Japan. The students had participated in the Third International Mathematics and Science Study (TIMSS; A. E. Beaton et al., 1996). The author examined several self-beliefs and used variance estimation techniques for complex sampling designs. The author identified a number of significant relationships between self-beliefs and mathematics achievement. Students who attributed success in mathematics to controllable factors (e.g., hard work, studying at home) showed higher test scores whereas students who attributed success in mathematics at school to external factors (e.g., good luck) tended to earn lower mathematics test scores. These results extend the findings of previous research results because the author examined large national samples of students in cross-cultural settings as part of a comprehensive international assessment.

  13. Students’ Achievement Goals, Learning-Related Emotions and Academic Achievement

    PubMed Central

    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. Dissemination Strategies to Improve Implementation of the PHS Smoking Cessation Guideline in MCH Public Health Clinics: Experimental Evaluation Results and Contextual Factors

    ERIC Educational Resources Information Center

    Manfredi, Clara; Cho, Young Ik; Warnecke, Richard; Saunders, Stephen; Sullivan, Myrtis

    2011-01-01

    We report results from an experimental study that tested the effectiveness of dissemination interventions to improve implementation of smoking cessation guidelines in maternal and child public health clinics. We additionally examine individual clinic results for contextual explanations not apparent from the experimental findings alone. Twelve…

  15. Experimental results of active control on a large structure to suppress vibration

    NASA Technical Reports Server (NTRS)

    Dunn, H. J.

    1991-01-01

    Three design methods, Linear Quadratic Gaussian with Loop Transfer Recovery (LQG/LTR), H-infinity, and mu-synthesis, are used to obtain compensators for suppressing the vibrations of a 10-bay vertical truss structure, a component typical of what may be used to build a large space structure. For the design process the plant dynamic characteristics of the structure were determined experimentally using an identification method. The resulting compensators were implemented on a digital computer and tested for their ability to suppress the first bending mode response of the 10-bay vertical truss. Time histories of the measured motion are presented, and modal damping obtained during the experiments are compared with analytical predictions. The advantages and disadvantages of using the various design methods are discussed.

  16. Individuals achieve more accurate results with meters that are codeless and employ dynamic electrochemistry.

    PubMed

    Rao, Anoop; Wiley, Meg; Iyengar, Sridhar; Nadeau, Dan; Carnevale, Julie

    2010-01-01

    Studies have shown that controlling blood glucose can reduce the onset and progression of the long-term microvascular and neuropathic complications associated with the chronic course of diabetes mellitus. Improved glycemic control can be achieved by frequent testing combined with changes in medication, exercise, and diet. Technological advancements have enabled improvements in analytical accuracy of meters, and this paper explores two such parameters to which that accuracy can be attributed. Four blood glucose monitoring systems (with or without dynamic electrochemistry algorithms, codeless or requiring coding prior to testing) were evaluated and compared with respect to their accuracy. Altogether, 108 blood glucose values were obtained for each system from 54 study participants and compared with the reference values. The analysis depicted in the International Organization for Standardization table format indicates that the devices with dynamic electrochemistry and the codeless feature had the highest proportion of acceptable results overall (System A, 101/103). Results were significant when compared at the 10% bias level with meters that were codeless and utilized static electrochemistry (p = .017) or systems that had static electrochemistry but needed coding (p = .008). Analytical performance of these blood glucose meters differed significantly depending on their technologic features. Meters that utilized dynamic electrochemistry and did not require coding were more accurate than meters that used static electrochemistry or required coding. 2010 Diabetes Technology Society.

  17. 5 a day Achievement Badge for African-American Boy Scouts: pilot outcome results.

    PubMed

    Baranowski, Tom; Baranowski, Janice; Cullen, Karen W; deMoor, Carl; Rittenberry, LaTroy; Hebert, David; Jones, Lovell

    2002-03-01

    Boy Scouts are an important channel to complement school-based programs to enable boys to eat more fruit, 100% juice, and vegetables (FJV) for chronic disease prevention. The "5 a Day Achievement Badge" program was presented on a pilot study basis to African-American Boy Scout troops in Houston. Troops were the unit of recruitment and random assignment to treatment and control groups. The badge program was presented in Fall 1997 by trained dietitians and included activities to increase availability and accessibility of fruit and vegetables at scouts' homes, increase preferences for vegetables, and train in the preparation of FaSST (fast, simple, safe, and tasty) recipes. Weekly comic books demonstrated and reinforced what scouts were expected to do at home. A weekly newsletter with recipes was sent to parents. The program was revised and presented to the control group in Winter 1998. Two 24-h recalls were the primary assessment tools. Telephone interviews were conducted with parents. The intervention resulted in a 0.8 FJV serving difference (post values of treatment versus control groups with pre value covaried). The changes obtained suggest that the intervention was effective in promoting dietary change. (C)2002 American Health Foundation and Elsevier Science (USA).

  18. The Effects of Homework Activities and Teaching Strategies for New Mathematics Topics on Achievement of Adolescent Students in Japan: Results from the TIMSS 1999 Assessment

    ERIC Educational Resources Information Center

    House, J. Daniel

    2004-01-01

    The importance of homework activities for student achievement has been extensively discussed. Research has indicated that, in general, students who spend more time on homework tend to show higher levels of academic achievement. For instance, results from the Third International Mathematics Study (TIMSS) indicated that adolescent students in Japan…

  19. Experimental realization of a terahertz all-dielectric metasurface absorber.

    PubMed

    Liu, Xinyu; Fan, Kebin; Shadrivov, Ilya V; Padilla, Willie J

    2017-01-09

    Metamaterial absorbers consisting of metal, metal-dielectric, or dielectric materials have been realized across much of the electromagnetic spectrum and have demonstrated novel properties and applications. However, most absorbers utilize metals and thus are limited in applicability due to their low melting point, high Ohmic loss and high thermal conductivity. Other approaches rely on large dielectric structures and / or a supporting dielectric substrate as a loss mechanism, thereby realizing large absorption volumes. Here we present a terahertz (THz) all dielectric metasurface absorber based on hybrid dielectric waveguide resonances. We tune the metasurface geometry in order to overlap electric and magnetic dipole resonances at the same frequency, thus achieving an experimental absorption of 97.5%. A simulated dielectric metasurface achieves a total absorption coefficient enhancement factor of FT=140, with a small absorption volume. Our experimental results are well described by theory and simulations and not limited to the THz range, but may be extended to microwave, infrared and optical frequencies. The concept of an all-dielectric metasurface absorber offers a new route for control of the emission and absorption of electromagnetic radiation from surfaces with potential applications in energy harvesting, imaging, and sensing.

  20. Online system for knowledge assessment enhances students' results on school knowledge test.

    PubMed

    Kralj, Benjamin; Glazar, Sasa Aleksej

    2013-01-01

    Variety of online tools were built to help assessing students' performance in school. Many teachers changed their methods of assessment from paper-and-pencil (P&P) to online systems. In this study we analyse the influence that using an online system for knowledge assessment has on students' knowledge. Based on both a literature study and our own research we designed and built an online system for knowledge assessment. The system is evaluated using two groups of primary school teachers and students (N = 686) in Slovenia: an experimental and a control group. Students solved P&P exams on several occasions. The experimental group was allowed to access the system either at school or at home for a limited period during the presentation of a selected school topic. Students in the experimental group were able to solve tasks and compare their own achievements with those of their coevals. A comparison of the P&P school exams results achieved by both groups revealed a positive effect on subject topic comprehension for those with access to the online self-assessment system.

  1. Experimental results for a two-dimensional supersonic inlet used as a thrust deflecting nozzle

    NASA Technical Reports Server (NTRS)

    Johns, Albert L.; Burstadt, Paul L.

    1984-01-01

    Nearly all supersonic V/STOL aircraft concepts are dependent on the thrust deflecting capability of a nozzle. In one unique concept, referred to as the reverse flow dual fan, not only is there a thrust deflecting nozzle for the fan and core engine exit flow, but because of the way the propulsion system operates during vertical takeoff and landing, the supersonic inlet is also used as a thrust deflecting nozzle. This paper presents results of an experimental study to evaluate the performance of a supersonic inlet used as a thrust deflecting nozzle for this reverse flow dual fan concept. Results are presented in terms of nozzle thrust coefficient and thrust vector angle for a number of inlet/nozzle configurations. Flow visualization and nozzle exit flow survey results are also shown.

  2. Identifying controlling variables for math computation fluency through experimental analysis: the interaction of stimulus control and reinforcing consequences.

    PubMed

    Hofstadter-Duke, Kristi L; Daly, Edward J

    2015-03-01

    This study investigated a method for conducting experimental analyses of academic responding. In the experimental analyses, academic responding (math computation), rather than problem behavior, was reinforced across conditions. Two separate experimental analyses (one with fluent math computation problems and one with non-fluent math computation problems) were conducted with three elementary school children using identical contingencies while math computation rate was measured. Results indicate that the experimental analysis with non-fluent problems produced undifferentiated responding across participants; however, differentiated responding was achieved for all participants in the experimental analysis with fluent problems. A subsequent comparison of the single-most effective condition from the experimental analyses replicated the findings with novel computation problems. Results are discussed in terms of the critical role of stimulus control in identifying controlling consequences for academic deficits, and recommendations for future research refining and extending experimental analysis to academic responding are made. © The Author(s) 2014.

  3. An experimental search strategy retrieves more precise results than PubMed and Google for questions about medical interventions

    PubMed Central

    Dylla, Daniel P.; Megison, Susan D.

    2015-01-01

    Objective. We compared the precision of a search strategy designed specifically to retrieve randomized controlled trials (RCTs) and systematic reviews of RCTs with search strategies designed for broader purposes. Methods. We designed an experimental search strategy that automatically revised searches up to five times by using increasingly restrictive queries as long at least 50 citations were retrieved. We compared the ability of the experimental and alternative strategies to retrieve studies relevant to 312 test questions. The primary outcome, search precision, was defined for each strategy as the proportion of relevant, high quality citations among the first 50 citations retrieved. Results. The experimental strategy had the highest median precision (5.5%; interquartile range [IQR]: 0%–12%) followed by the narrow strategy of the PubMed Clinical Queries (4.0%; IQR: 0%–10%). The experimental strategy found the most high quality citations (median 2; IQR: 0–6) and was the strategy most likely to find at least one high quality citation (73% of searches; 95% confidence interval 68%–78%). All comparisons were statistically significant. Conclusions. The experimental strategy performed the best in all outcomes although all strategies had low precision. PMID:25922798

  4. Impact of Integrated Science and English Language Arts Literacy Supplemental Instructional Intervention on Science Academic Achievement of Elementary Students

    NASA Astrophysics Data System (ADS)

    Marks, Jamar Terry

    The purpose of this quasi-experimental, nonequivalent pretest-posttest control group design study was to determine if any differences existed in upper elementary school students' science academic achievement when instructed using an 8-week integrated science and English language arts literacy supplemental instructional intervention in conjunction with traditional science classroom instruction as compared to when instructed using solely traditional science classroom instruction. The targeted sample population consisted of fourth-grade students enrolled in a public elementary school located in the southeastern region of the United States. The convenience sample size consisted of 115 fourth-grade students enrolled in science classes. The pretest and posttest academic achievement data collected consisted of the science segment from the Spring 2015, and Spring 2016 state standardized assessments. Pretest and posttest academic achievement data were analyzed using an ANCOVA statistical procedure to test for differences, and the researcher reported the results of the statistical analysis. The results of the study show no significant difference in science academic achievement between treatment and control groups. An interpretation of the results and recommendations for future research were provided by the researcher upon completion of the statistical analysis.

  5. Experimental investigation of practical unforgeable quantum money

    NASA Astrophysics Data System (ADS)

    Bozzio, Mathieu; Orieux, Adeline; Trigo Vidarte, Luis; Zaquine, Isabelle; Kerenidis, Iordanis; Diamanti, Eleni

    2018-01-01

    Wiesner's unforgeable quantum money scheme is widely celebrated as the first quantum information application. Based on the no-cloning property of quantum mechanics, this scheme allows for the creation of credit cards used in authenticated transactions offering security guarantees impossible to achieve by classical means. However, despite its central role in quantum cryptography, its experimental implementation has remained elusive because of the lack of quantum memories and of practical verification techniques. Here, we experimentally implement a quantum money protocol relying on classical verification that rigorously satisfies the security condition for unforgeability. Our system exploits polarization encoding of weak coherent states of light and operates under conditions that ensure compatibility with state-of-the-art quantum memories. We derive working regimes for our system using a security analysis taking into account all practical imperfections. Our results constitute a major step towards a real-world realization of this milestone protocol.

  6. NACA0012 benchmark model experimental flutter results with unsteady pressure distributions

    NASA Technical Reports Server (NTRS)

    Rivera, Jose A., Jr.; Dansberry, Bryan E.; Bennett, Robert M.; Durham, Michael H.; Silva, Walter A.

    1992-01-01

    The Structural Dynamics Division at NASA Langley Research Center has started a wind tunnel activity referred to as the Benchmark Models Program. The primary objective of this program is to acquire measured dynamic instability and corresponding pressure data that will be useful for developing and evaluating aeroelastic type computational fluid dynamics codes currently in use or under development. The program is a multi-year activity that will involve testing of several different models to investigate various aeroelastic phenomena. This paper describes results obtained from a second wind tunnel test of the first model in the Benchmark Models Program. This first model consisted of a rigid semispan wing having a rectangular planform and a NACA 0012 airfoil shape which was mounted on a flexible two degree of freedom mount system. Experimental flutter boundaries and corresponding unsteady pressure distribution data acquired over two model chords located at the 60 and 95 percent span stations are presented.

  7. Active vibration absorber for CSI evolutionary model: Design and experimental results

    NASA Technical Reports Server (NTRS)

    Bruner, Anne M.; Belvin, W. Keith; Horta, Lucas G.; Juang, Jer-Nan

    1991-01-01

    The development of control of large flexible structures technology must include practical demonstration to aid in the understanding and characterization of controlled structures in space. To support this effort, a testbed facility was developed to study practical implementation of new control technologies under realistic conditions. The design is discussed of a second order, acceleration feedback controller which acts as an active vibration absorber. This controller provides guaranteed stability margins for collocated sensor/actuator pairs in the absence of sensor/actuator dynamics and computational time delay. The primary performance objective considered is damping augmentation of the first nine structural modes. Comparison of experimental and predicted closed loop damping is presented, including test and simulation time histories for open and closed loop cases. Although the simulation and test results are not in full agreement, robustness of this design under model uncertainty is demonstrated. The basic advantage of this second order controller design is that the stability of the controller is model independent.

  8. Experimental Estimation Of Energy Damping During Free Rocking Of Unreinforced Masonry Walls. First Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sorrentino, Luigi; Masiani, Renato; Benedetti, Stefano

    2008-07-08

    This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free rocking. Aim of the laboratory campaign is the estimation of kinetic energy damping exhibited by walls released with non-zero initial conditions of motion. Such energy damping is necessary for dynamic modelling of unreinforced masonry local mechanisms. After a brief review of the literature on this topic, the main features of the laboratory tests are presented. The program involves the experimental investigation of several parameters: 1) unit material (brick or tuff), 2) wall aspect ratio (ranging between 14.5 and 7.1), 3) restraint condition (two-sided or one-sided rocking), andmore » 4) depth of the contact surface between facade and transverse walls (one-sided rocking only). All walls are single wythe and the mortar is pozzuolanic. The campaign is still in progress. However, it is possible to present the results on most of the mechanical properties of mortar and bricks. Moreover, a few time histories are reported, already indicating the need to correct some of the assumptions frequent in the literature.« less

  9. A comparison of experimental and theoretical results for leakage, pressure distribution, and rotordynamic coefficients for annular gas seals

    NASA Technical Reports Server (NTRS)

    Nicks, C. O.; Childs, D. W.

    1984-01-01

    The importance of seal behavior in rotordynamics is discussed and current annular seal theory is reviewed. A Nelson's analytical-computational method for determining rotordynamic coefficients for this type of compressible-flow seal is outlined. Various means for the experimental identification of the dynamic coefficients are given, and the method employed at the Texas A and M University (TAMU) test facility is explained. The TAMU test apparatus is described, and the test procedures are discussed. Experimental results, including leakage, entrance-loss coefficients, pressure distributions, and rotordynamic coefficients for a smooth and a honeycomb constant-clearance seal are presented and compared to theoretical results from Nelson's analysis. The results for both seals show little sensitivity to the running speed over the test range. Agreement between test results and theory for leakage through the seal is satisfactory. Test results for direct stiffness show a greater sensitivity to fluid pre-rotation than predicted. Results also indicate that the deliberately roughened surface of the honeycomb seal provides improved stability versus the smooth seal.

  10. An Analysis of Mathematics Course Sequences for Low Achieving Students at a Comprehensive Technical High School

    ERIC Educational Resources Information Center

    Edge, D. Michael

    2011-01-01

    This non-experimental study attempted to determine how the different prescribed mathematic tracks offered at a comprehensive technical high school influenced the mathematics performance of low-achieving students on standardized assessments of mathematics achievement. The goal was to provide an analysis of any statistically significant differences…

  11. Raman Computational and Experimental Studies of Dopamine Detection

    PubMed Central

    Ciubuc, John D.; Bennet, Kevin E.; Qiu, Chao; Alonzo, Matthew; Durrer, William G.; Manciu, Felicia S.

    2017-01-01

    A combined theoretical and experimental analysis of dopamine (DA) is presented in this work with the objective of achieving more accurate detection and monitoring of this neurotransmitter at very low concentrations, specific to physiological levels. Surface-enhanced Raman spectroscopy on silver nanoparticles was employed for recording DA concentrations as low as 10−11 molar. Quantum chemical density functional calculations were carried out using Gaussian-09 analytical suite software. Relatively good agreement between the simulated and experimentally determined results indicates the presence of different DA molecular forms, such as uncharged DA±, anionic DA−, and dopaminequinone. Disappearance of the strongest bands of dopamine around 750 cm−1 and 790 cm−1, which suggests its adsorption onto the metallic surface, is not only consistent with all of these DA configurations, but also provides additional information about the analyte’s redox process and voltammetric detection. On the other hand, occurrence of the abovementioned Raman lines could indicate the formation of multilayers of DA or its presence in a cationic DA+ form. Thus, through coordinated experiment and theory, valuable insights into changes observed in the vibrational signatures of this important neurotransmitter can be achieved for a better understanding of its detection at physiological levels, which is crucial if further optovoltammetric medical device development is envisioned. PMID:28956820

  12. Dynamic Geometry Software Improves Mathematical Achievement: Systematic Review and Meta-Analysis

    ERIC Educational Resources Information Center

    Chan, Kan Kan; Leung, Siu Wai

    2014-01-01

    Dynamic geometry software (DGS) aims to enhance mathematics education. This systematic review and meta-analysis evaluated the quasi-experimental studies on the effectiveness of DGS-based instruction in improving students' mathematical achievement. Research articles published between 1990 and 2013 were identified from major databases according to a…

  13. The Effects of Playing Educational Video Games on Kindergarten Achievement.

    ERIC Educational Resources Information Center

    Din, Feng S.; Calao, Josephine

    2001-01-01

    Investigated whether kindergarten students who played Sony PlayStation educational video games for 40 minutes daily for 11 weeks learned better than peers who did not play such games. Found that the experimental group gained significantly more than the control group in spelling and decoding on the Wide Range Achievement Test-R3. Found no…

  14. Data-Mining Techniques in Detecting Factors Linked to Academic Achievement

    ERIC Educational Resources Information Center

    Martínez Abad, Fernando; Chaparro Caso López, Alicia A.

    2017-01-01

    In light of the emergence of statistical analysis techniques based on data mining in education sciences, and the potential they offer to detect non-trivial information in large databases, this paper presents a procedure used to detect factors linked to academic achievement in large-scale assessments. The study is based on a non-experimental,…

  15. Baseline Experimental Results on the Effect of Oil Temperature on Shrouded Meshed Spur Gear Windage Power Loss

    NASA Technical Reports Server (NTRS)

    Delgado, Irebert R.; Hurrell, Michael

    2017-01-01

    Rotorcraft gearbox efficiencies are reduced at increased surface speeds due to viscous and impingement drag on the gear teeth. This windage power loss can affect overall mission range, payload, and frequency of transmission maintenance. Experimental and analytical studies on shrouding for single gears have shown it to be potentially effective in mitigating windage power loss. Efficiency studies on unshrouded meshed gears have shown the effect of speed, oil viscosity, temperature, load, lubrication scheme, etc. on gear windage power loss. The open literature does not contain experimental test data on shrouded meshed spur gears. Gear windage power loss test results are presented on shrouded meshed spur gears at elevated oil inlet temperatures and constant oil pressure both with and without shrouding. Shroud effectiveness is compared at four oil inlet temperatures. The results are compared to the available literature and follow-up work is outlined.

  16. Experimental selective posterior semicircular canal laser deafferentation.

    PubMed

    Naguib, Maged B

    2005-05-01

    In this experimental study, we attempted to perform selective deafferentation of the posterior semicircular canal ampulla of guinea pigs using carbon dioxide laser beam. The results of this study document the efficacy of this procedure in achieving deafferentation of the posterior semicircular canal safely with regards to the other semicircular canals, the otolithic organ and the organ of hearing. Moreover, the procedure is performed with relative ease compared with other procedures previously described for selective deafferentation of the posterior semicircular canal. The clinical application of such a procedure for the treatment of intractable benign paroxysmal positional vertigo in humans is suggested.

  17. Engaging College Science Students and Changing Academic Achievement with Technology: A Quasi-Experimental Preliminary Investigation

    ERIC Educational Resources Information Center

    Carle, Adam C.; Jaffee, David; Miller, Deborah

    2009-01-01

    Can modern, computer-based technology engage college students and improve their academic achievement in college? Although numerous examples detail technology's classroom uses, few studies empirically examine whether technologically oriented pedagogical changes factually lead to positive outcomes among college students. In this pilot study, we used…

  18. The Achievement Ideology and Whiteness: "Achieving Whiteness" or "Achieving Middle Class?"

    ERIC Educational Resources Information Center

    Allen, Ricky Lee

    Over the past few decades, social reproduction theorists have criticized achievement ideology as a dominant and dominating myth that hides the true nature of class immobility. Social reproductionists' primary criticism of achievement ideology is that it blinds the working class, regardless of race or gender, to the possibilities of collective…

  19. Experimental problem solving: An instructional improvement field experiment

    NASA Astrophysics Data System (ADS)

    Ross, John A.; Maynes, Florence J.

    An instructional program based on expert-novice differences in experimental problem-solving performance was taught to grade 6 students (N = 265). Classes of students were randomly assigned to conditions in a delayed treatment design. Performance was assessed with multiple-choice and open-ended measures of specific transfer. Between group comparisons using pretest scores as a covariate showed that treatment condition students consistently outperformed controls; similar results were revealed in the within group comparisons. The achievement of the early treatment group did not decline in tests administered one month after the posttest.

  20. SIDDHARTA results and implications of the results on antikaon-nucleon interaction

    NASA Astrophysics Data System (ADS)

    Marton, J.; Bazzi, M.; Beer, G.; Berucci, C.; Bellotti, G.; Bosnar, D.; Bragadireanu, A. M.; Cargnelli, M.; Clozza, A.; Curceanu, C.; Butt, A. Dawood; Fiorini, C.; Ghio, F.; Guaraldo, C.; Hayano, R.; Iliescu, M.; Iwasaki, M.; Sandri, P. Levi; Okada, S.; Pietreanu, D.; Piscicchia, K.; Vidal, A. Romero; Scordo, A.; Shi, H.; Sirghi, D. L.; Sirghi, F.; Tatsuno, H.; Doce, O. Vazquez; Widmann, E.; Zmeskal, J.

    2016-05-01

    The interaction of antikaons (K-) with nucleons and nuclei in the low-energy regime represents an active research field in hadron physics. There are important open questions like the existence of antikaon nuclear bound states like the prototype system being K- pp. Unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states in light kaonic atoms like kaonic hydrogen and helium isotopes. In the SIDDHARTA experiment at the electron-positron collider DAΦNE of LNF-INFN we measured the most precise values of the strong interaction observables, i.e. the strong interaction on the 1s ground state of the electromagnetically bound K-p atom leading to energy shift and broadening of the 1s state. The SIDDHARTA result triggered new theoretical work, which achieved major progress in the understanding of the low-energy strong interaction with strangeness reflected by the antikaon-nucleon scattering lengths calculated with the K--proton amplitudes constrained by the SIDDHARTA data. The most important open question is the experimental determination of the hadronic energy shift and width of kaonic deuterium which is planned by the SIDDHARTA-2 Collaboration.

  1. Technical Note: Experimental results from a prototype high-field inline MRI-linac

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liney, G. P., E-mail: gary.liney@sswahs.nsw.gov.au

    Purpose: The pursuit of real-time image guided radiotherapy using optimal tissue contrast has seen the development of several hybrid magnetic resonance imaging (MRI)-treatment systems, high field and low field, and inline and perpendicular configurations. As part of a new MRI-linac program, an MRI scanner was integrated with a linear accelerator to enable investigations of a coupled inline MRI-linac system. This work describes results from a prototype experimental system to demonstrate the feasibility of a high field inline MR-linac. Methods: The magnet is a 1.5 T MRI system (Sonata, Siemens Healthcare) was located in a purpose built radiofrequency (RF) cage enablingmore » shielding from and close proximity to a linear accelerator with inline (and future perpendicular) orientation. A portable linear accelerator (Linatron, Varian) was installed together with a multileaf collimator (Millennium, Varian) to provide dynamic field collimation and the whole assembly built onto a stainless-steel rail system. A series of MRI-linac experiments was performed to investigate (1) image quality with beam on measured using a macropodine (kangaroo) ex vivo phantom; (2) the noise as a function of beam state measured using a 6-channel surface coil array; and (3) electron contamination effects measured using Gafchromic film and an electronic portal imaging device (EPID). Results: (1) Image quality was unaffected by the radiation beam with the macropodine phantom image with the beam on being almost identical to the image with the beam off. (2) Noise measured with a surface RF coil produced a 25% elevation of background intensity when the radiation beam was on. (3) Film and EPID measurements demonstrated electron focusing occurring along the centerline of the magnet axis. Conclusions: A proof-of-concept high-field MRI-linac has been built and experimentally characterized. This system has allowed us to establish the efficacy of a high field inline MRI-linac and study a number of the

  2. Concept for Geostationary Experimental Temperature and Moisture Sounder (GETMS)

    NASA Technical Reports Server (NTRS)

    Kumer, J. B.; Sterrit, L. W.; Steakley, B. C.; Springer, L. A.; Roche, A. E.; Rosenberg, W. J.; James, T. C.; Shenk, W. E.; Susskind, J.; Chesters, D.

    1988-01-01

    The concept of the Geostationary Experimental Temperature and Moisture Sounder (GETMS) is described, with special attention given to the system constraints and its performance characteristics. The GETMS concept supports operation in a high-resolution 'nominal experimental mode' that could achieve spectral resolution of the order 0.2/cm in the 4.2-micron region with signal/noise sufficient to achieve temperature profile retrievals with vertical resolution of the order 1 to 2 km and accuracy to 1 K or less. The concept includes a cryogenic module to provide cryogenic cooling of the focal plane. The GETMS functional diagram and diagrams of the GETMS spectrometer and of the cryogenics module are included.

  3. Experimental and Computational Aerothermodynamics of a Mars Entry Vehicle

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.

    1996-01-01

    An aerothermodynamic database has been generated through both experimental testing and computational fluid dynamics simulations for a 70 deg sphere-cone configuration based on the NASA Mars Pathfinder entry vehicle. The aerothermodynamics of several related parametric configurations were also investigated. Experimental heat-transfer data were obtained at hypersonic test conditions in both a perfect gas air wind tunnel and in a hypervelocity, high-enthalpy expansion tube in which both air and carbon dioxide were employed as test gases. In these facilities, measurements were made with thin-film temperature-resistance gages on both the entry vehicle models and on the support stings of the models. Computational results for freestream conditions equivalent to those of the test facilities were generated using an axisymmetric/2D laminar Navier-Stokes solver with both perfect-gas and nonequilibrium thermochemical models. Forebody computational and experimental heating distributions agreed to within the experimental uncertainty for both the perfect-gas and high-enthalpy test conditions. In the wake, quantitative differences between experimental and computational heating distributions for the perfect-gas conditions indicated transition of the free shear layer near the reattachment point on the sting. For the high enthalpy cases, agreement to within, or slightly greater than, the experimental uncertainty was achieved in the wake except within the recirculation region, where further grid resolution appeared to be required. Comparisons between the perfect-gas and high-enthalpy results indicated that the wake remained laminar at the high-enthalpy test conditions, for which the Reynolds number was significantly lower than that of the perfect-gas conditions.

  4. Mathematics anxiety and mathematics achievement

    NASA Astrophysics Data System (ADS)

    Sherman, Brian F.; Wither (Post.), David P.

    2003-09-01

    This paper is a distillation of the major result from the 1998 Ph.D. thesis of the late David Wither. It details a longitudinal study over five years of the relationship between mathematics anxiety and mathematics achievement. It starts from the already well documented negative correlation between the two, and seeks to establish one of the three hypotheses—that mathematics anxiety causes an impairment of mathematics achievement; that lack of mathematics achievement causes mathematics anxiety; or that there is a third underlying cause of the two.

  5. CSI Flight Computer System and experimental test results

    NASA Technical Reports Server (NTRS)

    Sparks, Dean W., Jr.; Peri, F., Jr.; Schuler, P.

    1993-01-01

    This paper describes the CSI Computer System (CCS) and the experimental tests performed to validate its functionality. This system is comprised of two major components: the space flight qualified Excitation and Damping Subsystem (EDS) which performs controls calculations; and the Remote Interface Unit (RIU) which is used for data acquisition, transmission, and filtering. The flight-like RIU is the interface between the EDS and the sensors and actuators positioned on the particular structure under control. The EDS and RIU communicate over the MIL-STD-1553B, a space flight qualified bus. To test the CCS under realistic conditions, it was connected to the Phase-0 CSI Evolutionary Model (CEM) at NASA Langley Research Center. The following schematic shows how the CCS is connected to the CEM. Various tests were performed which validated the ability of the system to perform control/structures experiments.

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

    PubMed

    Hornstra, Lisette; Majoor, Marieke; Peetsma, Thea

    2017-12-01

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

  7. The effect of homogeneous and heterogeneous review pairs on student achievement and attitude when utilizing computer-assisted instruction in middle-level Earth science classes

    NASA Astrophysics Data System (ADS)

    Lyon, Ellen Beth

    1998-09-01

    This research project investigated the influence of homogeneous (like-ability) review pairs coupled with heterogeneous (mixed-ability) cooperative learning groups using computer-assisted instruction (CAI) on academic achievement and attitude toward science in eighth grade Earth science students. Subjects were placed into academic quartiles (Hi, Med-Hi, Med-Lo, and Lo) based on achievement. Cooperative learning groups of four (one student from each academic quartile) were formed in all classes, within which students completed CAI through a software package entitled Geoscience Education Through Interactive Technology, or GETITspTM. Each day, when computer activities were completed, students in the experimental classes were divided into homogeneous review pairs to review their work. The students in the control classes were divided into heterogeneous review pairs to review their work. The effects of the experimental treatment were measured by pretest, posttest, and delayed posttest measures, by pre- and post-student attitude scales, and by evaluation of amendments students made to their work during the time spent in review pairs. Results showed that student achievement was not significantly influenced by placement in homogeneous or heterogeneous review pairs, regardless of academic quartile assignment. Student attitude toward science as a school subject did not change significantly due to experimental treatment. Achievement retention of students in experimental and control groups within each quartile showed no significant difference. Notebook amendment patterns showed some significant differences in a few categories. For the Hi quartile, there were significant differences in numbers of deletion amendments and substitution amendments between the experimental and the control group. In both cases, subjects in the experimental group (homogeneous review pairs) made greater number of amendments then those in the control group (heterogeneous review pairs). For the Lo quartile

  8. Photoionization microscopy: Hydrogenic theory in semiparabolic coordinates and comparison with experimental results

    NASA Astrophysics Data System (ADS)

    Kalaitzis, P.; Danakas, S.; Lépine, F.; Bordas, C.; Cohen, S.

    2018-05-01

    Photoionization microscopy (PM) is an experimental method allowing for high-resolution measurements of the electron current probability density in the case of photoionization of an atom in an external uniform static electric field. PM is based on high-resolution velocity-map imaging and offers the unique opportunity to observe the quantum oscillatory spatial structure of the outgoing electron flux. We present the basic elements of the quantum-mechanical theoretical framework of PM for hydrogenic systems near threshold. Our development is based on the computationally more convenient semiparabolic coordinate system. Theoretical results are first subjected to a quantitative comparison with hydrogenic images corresponding to quasibound states and a qualitative comparison with nonresonant images of multielectron atoms. Subsequently, particular attention is paid on the structure of the electron's momentum distribution transversely to the static field (i.e., of the angularly integrated differential cross-section as a function of electron energy and radius of impact on the detector). Such 2D maps provide at a glance a complete picture of the peculiarities of the differential cross-section over the entire near-threshold energy range. Hydrogenic transverse momentum distributions are computed for the cases of the ground and excited initial states and single- and two-photon ionization schemes. Their characteristics of general nature are identified by comparing the hydrogenic distributions among themselves, as well as with a presently recorded experimental distribution concerning the magnesium atom. Finally, specificities attributed to different target atoms, initial states, and excitation scenarios are also discussed, along with directions of further work.

  9. Achievement as Resistance: The Development of a Critical Race Achievement Ideology among Black Achievers

    ERIC Educational Resources Information Center

    Carter, Dorinda J.

    2008-01-01

    In this article, Dorinda Carter examines the embodiment of a critical race achievement ideology in high-achieving black students. She conducted a yearlong qualitative investigation of the adaptive behaviors that nine high-achieving black students developed and employed to navigate the process of schooling at an upper-class, predominantly white,…

  10. Preliminary results of the large experimental wind turbine phase of the national wind energy program

    NASA Technical Reports Server (NTRS)

    Thomas, R. L.; Sholes, T.; Sholes, J. E.

    1975-01-01

    The preliminary results of two projects in the development phase of reliable wind turbines designed to supply cost-competitive electrical energy were discussed. An experimental 100 kW wind turbine design and its status are first reviewed. The results of two parallel design studies for determining the configurations and power levels for wind turbines with minimum energy costs are also discussed. These studies predict wind energy costs of 1.5 to 7 cents per kW-h for wind turbines produced in quantities of 100 to 1000 per year and located at sites having average winds of 12 to 18 mph.

  11. Experimental results on antiproton-nuclei annihilation cross section at very low energies

    NASA Astrophysics Data System (ADS)

    Aghai-Khozani, H.; Barna, D.; Corradini, M.; Hayano, R.; Hori, M.; Kobayashi, T.; Leali, M.; Lodi-Rizzini, E.; Mascagna, V.; Prest, M.; Soter, A.; Todoroki, K.; Vallazza, E.; Venturelli, L.; Zurlo, N.

    2014-03-01

    Investigating the antiproton cross section on nuclei at low energies (1 eV - 1 MeV) is of great interest for fundamental cosmology and nuclear physics as well. The process is of great relevance for the models which try to explain the matter/antimatter asymmetry in the universe assuming the existence of the so-called "island" where antinucleon-nucleon annihilations occur in the border region [1]. For the nuclear physics point of view, the annihilation process is considered a useful tool to evaluate the neutron/proton ratio probing the external region of the nucleus. Moreover, the cross section measured at LEAR in the 80s-90s showed an unexpected behaviour for energies below 1 MeV. The results showed a saturation with the atomic mass number against the A2/3 trend which is known for higher energies. The ASACUSA collaboration at CERN measured 5.3 MeV antiproton annihilation cross section on different nuclei whose results demonstrated to be consistent with the black-disk model with the Coulomb correction [2]. So far, experimental limits prevented the data acquisition for energies below 1 MeV. In 2012 the 100 keV region has been investigated for the first time [3]. We present here the results of the experiment.

  12. A hierarchy of models for simulating experimental results from a 3D heterogeneous porous medium

    NASA Astrophysics Data System (ADS)

    Vogler, Daniel; Ostvar, Sassan; Paustian, Rebecca; Wood, Brian D.

    2018-04-01

    In this work we examine the dispersion of conservative tracers (bromide and fluorescein) in an experimentally-constructed three-dimensional dual-porosity porous medium. The medium is highly heterogeneous (σY2 = 5.7), and consists of spherical, low-hydraulic-conductivity inclusions embedded in a high-hydraulic-conductivity matrix. The bimodal medium was saturated with tracers, and then flushed with tracer-free fluid while the effluent breakthrough curves were measured. The focus for this work is to examine a hierarchy of four models (in the absence of adjustable parameters) with decreasing complexity to assess their ability to accurately represent the measured breakthrough curves. The most information-rich model was (1) a direct numerical simulation of the system in which the geometry, boundary and initial conditions, and medium properties were fully independently characterized experimentally with high fidelity. The reduced-information models included; (2) a simplified numerical model identical to the fully-resolved direct numerical simulation (DNS) model, but using a domain that was one-tenth the size; (3) an upscaled mobile-immobile model that allowed for a time-dependent mass-transfer coefficient; and, (4) an upscaled mobile-immobile model that assumed a space-time constant mass-transfer coefficient. The results illustrated that all four models provided accurate representations of the experimental breakthrough curves as measured by global RMS error. The primary component of error induced in the upscaled models appeared to arise from the neglect of convection within the inclusions. We discuss the necessity to assign value (via a utility function or other similar method) to outcomes if one is to further select from among model options. Interestingly, these results suggested that the conventional convection-dispersion equation, when applied in a way that resolves the heterogeneities, yields models with high fidelity without requiring the imposition of a more

  13. Comparison of thermal analytic model with experimental test results for 30-sentimeter-diameter engineering model mercury ion thruster

    NASA Technical Reports Server (NTRS)

    Oglebay, J. C.

    1977-01-01

    A thermal analytic model for a 30-cm engineering model mercury-ion thruster was developed and calibrated using the experimental test results of tests of a pre-engineering model 30-cm thruster. A series of tests, performed later, simulated a wide range of thermal environments on an operating 30-cm engineering model thruster, which was instrumented to measure the temperature distribution within it. The modified analytic model is described and analytic and experimental results compared for various operating conditions. Based on the comparisons, it is concluded that the analytic model can be used as a preliminary design tool to predict thruster steady-state temperature distributions for stage and mission studies and to define the thermal interface bewteen the thruster and other elements of a spacecraft.

  14. The mzTab Data Exchange Format: Communicating Mass-spectrometry-based Proteomics and Metabolomics Experimental Results to a Wider Audience*

    PubMed Central

    Griss, Johannes; Jones, Andrew R.; Sachsenberg, Timo; Walzer, Mathias; Gatto, Laurent; Hartler, Jürgen; Thallinger, Gerhard G.; Salek, Reza M.; Steinbeck, Christoph; Neuhauser, Nadin; Cox, Jürgen; Neumann, Steffen; Fan, Jun; Reisinger, Florian; Xu, Qing-Wei; del Toro, Noemi; Pérez-Riverol, Yasset; Ghali, Fawaz; Bandeira, Nuno; Xenarios, Ioannis; Kohlbacher, Oliver; Vizcaíno, Juan Antonio; Hermjakob, Henning

    2014-01-01

    The HUPO Proteomics Standards Initiative has developed several standardized data formats to facilitate data sharing in mass spectrometry (MS)-based proteomics. These allow researchers to report their complete results in a unified way. However, at present, there is no format to describe the final qualitative and quantitative results for proteomics and metabolomics experiments in a simple tabular format. Many downstream analysis use cases are only concerned with the final results of an experiment and require an easily accessible format, compatible with tools such as Microsoft Excel or R. We developed the mzTab file format for MS-based proteomics and metabolomics results to meet this need. mzTab is intended as a lightweight supplement to the existing standard XML-based file formats (mzML, mzIdentML, mzQuantML), providing a comprehensive summary, similar in concept to the supplemental material of a scientific publication. mzTab files can contain protein, peptide, and small molecule identifications together with experimental metadata and basic quantitative information. The format is not intended to store the complete experimental evidence but provides mechanisms to report results at different levels of detail. These range from a simple summary of the final results to a representation of the results including the experimental design. This format is ideally suited to make MS-based proteomics and metabolomics results available to a wider biological community outside the field of MS. Several software tools for proteomics and metabolomics have already adapted the format as an output format. The comprehensive mzTab specification document and extensive additional documentation can be found online. PMID:24980485

  15. Experimental study of thermal rectification in suspended monolayer graphene

    PubMed Central

    Wang, Haidong; Hu, Shiqian; Takahashi, Koji; Zhang, Xing; Takamatsu, Hiroshi; Chen, Jie

    2017-01-01

    Thermal rectification is a fundamental phenomenon for active heat flow control. Significant thermal rectification is expected to exist in the asymmetric nanostructures, such as nanowires and thin films. As a one-atom-thick membrane, graphene has attracted much attention for realizing thermal rectification as shown by many molecular dynamics simulations. Here, we experimentally demonstrate thermal rectification in various asymmetric monolayer graphene nanostructures. A large thermal rectification factor of 26% is achieved in a defect-engineered monolayer graphene with nanopores on one side. A thermal rectification factor of 10% is achieved in a pristine monolayer graphene with nanoparticles deposited on one side or with a tapered width. The results indicate that the monolayer graphene has great potential to be used for designing high-performance thermal rectifiers for heat flow control and energy harvesting. PMID:28607493

  16. Experimental study of thermal rectification in suspended monolayer graphene.

    PubMed

    Wang, Haidong; Hu, Shiqian; Takahashi, Koji; Zhang, Xing; Takamatsu, Hiroshi; Chen, Jie

    2017-06-13

    Thermal rectification is a fundamental phenomenon for active heat flow control. Significant thermal rectification is expected to exist in the asymmetric nanostructures, such as nanowires and thin films. As a one-atom-thick membrane, graphene has attracted much attention for realizing thermal rectification as shown by many molecular dynamics simulations. Here, we experimentally demonstrate thermal rectification in various asymmetric monolayer graphene nanostructures. A large thermal rectification factor of 26% is achieved in a defect-engineered monolayer graphene with nanopores on one side. A thermal rectification factor of 10% is achieved in a pristine monolayer graphene with nanoparticles deposited on one side or with a tapered width. The results indicate that the monolayer graphene has great potential to be used for designing high-performance thermal rectifiers for heat flow control and energy harvesting.

  17. Analysis on Experimental Investigation and Mathematical Modeling of Incompressible Flow Through Ceramic Foam Filters

    NASA Astrophysics Data System (ADS)

    Akbarnejad, Shahin; Jonsson, Lage Tord Ingemar; Kennedy, Mark William; Aune, Ragnhild Elizabeth; Jönsson, Pӓr Göran

    2016-08-01

    This paper presents experimental results of pressure drop measurements on 30, 50, and 80 pores per inch (PPI) commercial alumina ceramic foam filters (CFF) and compares the obtained pressure drop profiles to numerically modeled values. In addition, it is aimed at investigating the adequacy of the mathematical correlations used in the analytical and the computational fluid dynamics (CFD) simulations. It is shown that the widely used correlations for predicting pressure drop in porous media continuously under-predict the experimentally obtained pressure drop profiles. For analytical predictions, the negative deviations from the experimentally obtained pressure drop using the unmodified Ergun and Dietrich equations could be as high as 95 and 74 pct, respectively. For the CFD predictions, the deviation to experimental results is in the range of 84.3 to 88.5 pct depending on filter PPI. Better results can be achieved by applying the Forchheimer second-order drag term instead of the Brinkman-Forchheimer drag term. Thus, the final deviation of the CFD model estimates lie in the range of 0.3 to 5.5 pct compared to the measured values.

  18. [Achieving an educative strategy in undergraduate medical interns with respect to patients with diabetes].

    PubMed

    Medina-Figueroa, Alda María; Espinosa-Alarcón, Patricia Atzimba

    2007-01-01

    To estimate the achievement of an educative strategy that promoted participation of the development of the clinical aptitude of undergraduate medical students with regard to patients with diabetes. We conducted a quasi-experimental study with two groups of undergraduate medical students. We validated an instrument to explore clinical attitude concerning diabetes mellitus (ACDIME) with 30 items for each of six indicators. The instrument was applied at two general hospitals, before and after carrying out the educative strategies. In the experimental group, we conducted an educative strategy that promotes participation in developing clinical aptitude, while the customary strategy was developed in the control group. ACDIME consistency was 0.80. Both study groups were similar before the educative strategies (p = 0.165). Statistically significant differences existed after the strategies in all indicators were evaluated, in favor of the experimental group. The tendency to change, with a criterion of 50% or more, was only statistically significant in the experimental group (p < 0.0001). The ACDIME instrument is valid and reliable. The educative strategy that promoted participation is clearly superior to the customary strategy with regard to achievement.

  19. Effect of Silicon on the Desulfurization of Al-Killed Steels: Part II. Experimental Results and Plant Trials

    NASA Astrophysics Data System (ADS)

    Roy, Debdutta; Pistorius, Petrus Christiaan; Fruehan, Richard J.

    2013-10-01

    Recent observations suggest that increased silicon levels improve ladle desulfurization of aluminum-killed steel. A kinetic model was developed and presented in part I of this paper, demonstrating that increased silicon levels in steel suppress the consumption of aluminum by parasitic reactions like silica reduction and FeO/MnO reduction, thus making more aluminum available at the interface for desulfurization. The results are increases in the rate and the extent of desulfurization. Predictions were compared with laboratory induction furnace melts using 1 kg of steel and 0.1 kg slag. The experimental results demonstrate the beneficial effect of silicon on the desulfurization reaction and that alumina can be reduced out of the slag and aluminum picked up by the steel, if the silicon content in the steel is high enough. The experimental results are in close agreement with the model predictions. Plant trials also show that with increased silicon content, both the rate and extent of desulfurization increase; incorporating silicon early into the ladle desulfurization process leads to considerable savings in aluminum consumption.

  20. Survey of Experimental Results From One Year of PASP PLUS Orbital Operation

    NASA Technical Reports Server (NTRS)

    Guidice, D. A.; Curtis, H. B.; Piszczor, M. F.; Palys, J. R.

    1996-01-01

    With PASP Plus as its primary payload, the APEX satellite was launched by a standard Pegasus rocket released from a NASA B-52 aircraft on 3 August 1994. A 70 deg inclination, 363 km X 2550 km orbit was achieved, allowing both investigation of space plasma effects on high-voltage operation in the perigee region and investigation of space radiation effects on array power output from passage through the inner radiation belt in the apogee region. Data gathering by PASP Plus was begun on 7 Aug 94 and ended on 11 Aug 95. In one year, PASP Plus collected an order of magnitude more data on environmental interactions on solar arrays than all previous space-borne photovoltaic experiments combined. The test arrays flown and the interactions-measuring and space-environment sensors of PASP Plus are described. The results of measurements of leakage current under test-array positive biasing and arc rates under negative biasing as a function of bias voltage, plasma density, array orientation, and other conditions are presented. The results of measurements of test-array power-output degradation caused by space radiation are also examined.

  1. EXPERIMENTAL MODELLING OF AORTIC ANEURYSMS

    PubMed Central

    Doyle, Barry J; Corbett, Timothy J; Cloonan, Aidan J; O’Donnell, Michael R; Walsh, Michael T; Vorp, David A; McGloughlin, Timothy M

    2009-01-01

    A range of silicone rubbers were created based on existing commercially available materials. These silicones were designed to be visually different from one another and have distinct material properties, in particular, ultimate tensile strengths and tear strengths. In total, eleven silicone rubbers were manufactured, with the materials designed to have a range of increasing tensile strengths from approximately 2-4MPa, and increasing tear strengths from approximately 0.45-0.7N/mm. The variations in silicones were detected using a standard colour analysis technique. Calibration curves were then created relating colour intensity to individual material properties. All eleven materials were characterised and a 1st order Ogden strain energy function applied. Material coefficients were determined and examined for effectiveness. Six idealised abdominal aortic aneurysm models were also created using the two base materials of the study, with a further model created using a new mixing technique to create a rubber model with randomly assigned material properties. These models were then examined using videoextensometry and compared to numerical results. Colour analysis revealed a statistically significant linear relationship (p<0.0009) with both tensile strength and tear strength, allowing material strength to be determined using a non-destructive experimental technique. The effectiveness of this technique was assessed by comparing predicted material properties to experimentally measured methods, with good agreement in the results. Videoextensometry and numerical modelling revealed minor percentage differences, with all results achieving significance (p<0.0009). This study has successfully designed and developed a range of silicone rubbers that have unique colour intensities and material strengths. Strengths can be readily determined using a non-destructive analysis technique with proven effectiveness. These silicones may further aid towards an improved understanding of the

  2. The Impact of a State Takeover on Academic Achievement, School Performance, and School Leadership in a Rural South Carolina School District

    ERIC Educational Resources Information Center

    Bishop, Janice Zissette

    2009-01-01

    This case study on the impact of a state takeover in one of South Carolina's most rural school districts ("referred to as the County School District") was completed using a quasi-experimental mixed methods design to examine the impact on academic achievement, school performance, and school leadership as a result of the South Carolina…

  3. Experimental Results from the Thermal Energy Storage-2 (TES-2) Flight Experiment

    NASA Technical Reports Server (NTRS)

    Tolbert, Carol

    2000-01-01

    Thermal Energy Storage-2 (TES-2) is a flight experiment that flew on the Space Shuttle Endeavour (STS-72), in January 1996. TES-2 originally flew with TES-1 as part of the OAST-2 Hitchhiker payload on the Space Shuttle Columbia (STS-62) in early 1994. The two experiments, TES-1 and TES-2 were identical except for the fluoride salts to be characterized. TES-1 provided data on lithium fluoride (LiF), TES-2 provided data on a fluoride eutectic (LiF/CaF2). Each experiment was a complex autonomous payload in a Get-Away-Special payload canister. TES-1 operated flawlessly for 22 hr. Results were reported in a paper entitled, Effect of Microgravity on Materials Undergoing Melting and Freezing-The TES Experiment, by David Namkoong et al. A software failure in TES-2 caused its shutdown after 4 sec of operation. TES-1 and 2 were the first experiments in a four experiment suite designed to provide data for understanding the long duration microgravity behavior of thermal energy storage salts that undergo repeated melting and freezing. Such data have never been obtained before and have direct application for the development of space-based solar dynamic (SD) power systems. These power systems will store energy in a thermal energy salt such as lithium fluoride or a eutectic of lithium fluoride/calcium difluoride. The stored energy is extracted during the shade portion of the orbit. This enables the solar dynamic power system to provide constant electrical power over the entire orbit. Analytical computer codes were developed for predicting performance of a space-based solar dynamic power system. Experimental verification of the analytical predictions were needed prior to using the analytical results for future space power design applications. The four TES flight experiments were to be used to obtain the needed experimental data. This paper will address the flight results from the first and second experiments, TES-1 and 2, in comparison to the predicted results from the Thermal

  4. Heterogeneous boiling-up of superheated liquid at achievable superheat threshold.

    PubMed

    Ermakov, G V; Lipnyagov, E V; Perminov, S A; Gurashkin, A L

    2009-07-21

    The classical theory of homogeneous nucleation describes well the superheat threshold observed in experiments. It may be assumed therefore that homogeneous boiling-up of a liquid takes place in experiments, and the theory has been verified experimentally well. The streak photography used in this study showed that boiling-up of a superheated liquid at the threshold of the achievable superheat occurs at a limited number of surface fluctuation centers in a vessel, rather than in the bulk as one would expect with homogeneous nucleation. Thus, the homogeneous theory, which rather accurately describes the heterogeneous threshold of the achievable superheat, obviously is not confirmed in experiments.

  5. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures.

    PubMed

    Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D; Kuss, Daria J; Billieux, Joël

    2016-06-01

    Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games.

  6. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures

    PubMed Central

    Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D.; Kuss, Daria J.; Billieux, Joël

    2016-01-01

    Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games. PMID:27156376

  7. The Impact of Professional Learning Communities on Urban Teachers and Their Students' Reading and Math Achievement

    ERIC Educational Resources Information Center

    Williams, Deborah Johnson

    2011-01-01

    This study followed a causal comparative research design that utilized mixed methods. This non-experimental investigation sought to identify potential cause and effect relationships between variations in achievement data among schools. The purpose of the study was to determine if urban students' reading and math achievement increased as a result…

  8. Experimental purification of single qubits.

    PubMed

    Ricci, M; De Martini, F; Cerf, N J; Filip, R; Fiurásek, J; Macchiavello, C

    2004-10-22

    We report the experimental realization of the purification protocol for single qubits sent through a depolarizing channel. The qubits are associated with polarization states of single photons and the protocol is achieved by means of passive linear optical elements. The present approach may represent a convenient alternative to the distillation and error correction protocols of quantum information.

  9. Experimental Results for a Flapped Natural-laminar-flow Airfoil with High Lift/drag Ratio

    NASA Technical Reports Server (NTRS)

    Mcghee, R. J.; Viken, J. K.; Pfenninger, W.; Beasley, W. D.; Harvey, W. D.

    1984-01-01

    Experimental results have been obtained for a flapped natural-laminar-flow airfoil, NLF(1)-0414F, in the Langley Low-Turbulence Pressure Tunnel. The tests were conducted over a Mach number range from 0.05 to 0.40 and a chord Reynolds number range from about 3.0 x 10(6) to 22.0 x 10(6). The airfoil was designed for 0.70 chord laminar flow on both surfaces at a lift coefficient of 0.40, a Reynolds number of 10.0 x 10(6), and a Mach number of 0.40. A 0.125 chord simple flap was incorporated in the design to increase the low-drag, lift-coefficient range. Results were also obtained for a 0.20 chord split-flap deflected 60 deg.

  10. Early Intervention and Student Achievement

    ERIC Educational Resources Information Center

    Hormes, Mridula T.

    2009-01-01

    The United States Department of Education has been rigorous in holding all states accountable with regard to student achievement. The No Child Left Behind Act of 2001 clearly laid out federal mandates for all schools to follow. K-12 leaders of public schools are very aware of the fact that results in terms of student achievement need to improve…

  11. Experimental investigation and model verification for a GAX absorber

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Palmer, S.C.; Christensen, R.N.

    1996-12-31

    In the ammonia-water generator-absorber heat exchange (GAX) absorption heat pump, the heat and mass transfer processes which occur between the generator and absorber are the most crucial in assuring that the heat pump will achieve COPs competitive with those of current technologies. In this study, a model is developed for the heat and mass transfer processes that occur in a counter-current vertical fluted tube absorber (VFTA) with inserts. Correlations for heat and mass transfer in annuli are used to model the processes in the VTA. Experimental data is used to validate the model for three different insert geometries. Comparison ofmore » model results with experimental data provides insight into model corrections necessary to bring the model into agreement with the physical phenomena observed in the laboratory.« less

  12. The effect of numbered heads together (NHT) cooperative learning model on the cognitive achievement of students with different academic ability

    NASA Astrophysics Data System (ADS)

    Leasa, Marleny; Duran Corebima, Aloysius

    2017-01-01

    Learning models and academic ability may affect students’ achievement in science. This study, thus aimed to investigate the effect of numbered heads together (NHT) cooperative learning model on elementary students’ cognitive achievement in natural science. This study employed a quasi-experimental design with pretest-posttest non-equivalent control group with 2 x 2 factorial. There were two learning models compared NHT and the conventional, and two academic ability high and low. The results of ana Cova test confirmed the difference in the students’ cognitive achievement based on learning models and general academic ability. However, the interaction between learning models and academic ability did not affect the students’ cognitive achievement. In conclusion, teachers are strongly recommended to be more creative in designing learning using other types of cooperative learning models. Also, schools are required to create a better learning environment which is more cooperative to avoid unfair competition among students in the classroom and as a result improve the students’ academic ability. Further research needs to be conducted to explore the contribution of other aspects in cooperative learning toward cognitive achievement of students with different academic ability.

  13. Effects of Developed Electronic Instructional Medium on Students' Achievement in Biology

    ERIC Educational Resources Information Center

    Chinna, Nsofor Caroline; Dada, Momoh Gabriel

    2013-01-01

    The study investigated the effects of developed electronic instructional medium (video DVD instructional package) on students' achievement in Biology. It was guided by two research questions and two hypotheses, using a quasi-experimental, pretest-postest control group design. The sample comprised of 180 senior secondary, year two students from six…

  14. Supersonic Retropropulsion Experimental Results from the NASA Ames 9- x 7-Foot Supersonic Wind Tunnel

    NASA Technical Reports Server (NTRS)

    Berry, Scott A.; Rhode, Matthew N.; Edquist, Karl T.

    2012-01-01

    Supersonic retropropulsion was experimentally examined in the Ames Research Center 9x7-Foot Supersonic Wind Tunnel at Mach 1.8 and 2.4. The experimental model, previously designed for and tested in the Langley Research Center Unitary Plan Wind Tunnel at Mach 2.4, 3.5 and 4.6, was a 5-in diameter 70-deg sphere-cone forebody with a 9.55-in long cylindrical aftbody. The forebody was designed to accommodate up to four 4:1 area ratio nozzles, one on the model centerline and the other three on the half radius spaced 120-deg apart. Surface pressure and flow visualization were the primary measurements, including high-speed data to investigate the dynamics of the interactions between the bow and nozzle shocks. Three blowing configurations were tested with thrust coefficients up to 10 and angles of attack up to 20-deg. Preliminary results and observations from the test are provided

  15. Comparison of numerical and experimental results of the flow in the U9 Kaplan turbine model

    NASA Astrophysics Data System (ADS)

    Petit, O.; Mulu, B.; Nilsson, H.; Cervantes, M.

    2010-08-01

    The present work compares simulations made using the OpenFOAM CFD code with experimental measurements of the flow in the U9 Kaplan turbine model. Comparisons of the velocity profiles in the spiral casing and in the draft tube are presented. The U9 Kaplan turbine prototype located in Porjus and its model, located in Älvkarleby, Sweden, have curved inlet pipes that lead the flow to the spiral casing. Nowadays, this curved pipe and its effect on the flow in the turbine is not taken into account when numerical simulations are performed at design stage. To study the impact of the inlet pipe curvature on the flow in the turbine, and to get a better overview of the flow of the whole system, measurements were made on the 1:3.1 model of the U9 turbine. Previously published measurements were taken at the inlet of the spiral casing and just before the guide vanes, using the laser Doppler anemometry (LDA) technique. In the draft tube, a number of velocity profiles were measured using the LDA techniques. The present work extends the experimental investigation with a horizontal section at the inlet of the draft tube. The experimental results are used to specify the inlet boundary condition for the numerical simulations in the draft tube, and to validate the computational results in both the spiral casing and the draft tube. The numerical simulations were realized using the standard k-e model and a block-structured hexahedral wall function mesh.

  16. An approach to achieve progress in spacecraft shielding

    NASA Astrophysics Data System (ADS)

    Thoma, K.; Schäfer, F.; Hiermaier, S.; Schneider, E.

    2004-01-01

    Progress in shield design against space debris can be achieved only when a combined approach based on several tools is used. This approach depends on the combined application of advanced numerical methods, specific material models and experimental determination of input parameters for these models. Examples of experimental methods for material characterization are given, covering the range from quasi static to very high strain rates for materials like Nextel and carbon fiber-reinforced materials. Mesh free numerical methods have extraordinary capabilities in the simulation of extreme material behaviour including complete failure with phase changes, combined with shock wave phenomena and the interaction with structural components. In this paper the benefits from combining numerical methods, material modelling and detailed experimental studies for shield design are demonstrated. The following examples are given: (1) Development of a material model for Nextel and Kevlar-Epoxy to enable numerical simulation of hypervelocity impacts on complex heavy protection shields for the International Space Station. (2) The influence of projectile shape on protection performance of Whipple Shields and how experimental problems in accelerating such shapes can be overcome by systematic numerical simulation. (3) The benefits of using metallic foams in "sandwich bumper shields" for spacecraft and how to approach systematic characterization of such materials.

  17. Quantitative Assessment of the CCMC's Experimental Real-time SWMF-Geospace Results

    NASA Astrophysics Data System (ADS)

    Liemohn, Michael; Ganushkina, Natalia; De Zeeuw, Darren; Welling, Daniel; Toth, Gabor; Ilie, Raluca; Gombosi, Tamas; van der Holst, Bart; Kuznetsova, Maria; Maddox, Marlo; Rastaetter, Lutz

    2016-04-01

    Experimental real-time simulations of the Space Weather Modeling Framework (SWMF) are conducted at the Community Coordinated Modeling Center (CCMC), with results available there (http://ccmc.gsfc.nasa.gov/realtime.php), through the CCMC Integrated Space Weather Analysis (iSWA) site (http://iswa.ccmc.gsfc.nasa.gov/IswaSystemWebApp/), and the Michigan SWMF site (http://csem.engin.umich.edu/realtime). Presently, two configurations of the SWMF are running in real time at CCMC, both focusing on the geospace modules, using the BATS-R-US magnetohydrodynamic model, the Ridley Ionosphere Model, and with and without the Rice Convection Model for inner magnetospheric drift physics. While both have been running for several years, nearly continuous results are available since July 2015. Dst from the model output is compared against the Kyoto real-time Dst, in particular the daily minimum value of Dst to quantify the ability of the model to capture storms. Contingency tables are presented, showing that the run with the inner magnetosphere model is much better at reproducing storm-time values. For disturbances with a minimum Dst lower than -50 nT, this version yields a probability of event detection of 0.86 and a Heidke Skill Score of 0.60. In the other version of the SWMF, without the inner magnetospheric module included, the modeled Dst never dropped below -50 nT during the examined epoch.

  18. Challenges and Achievements in Prevention and Treatment of Smallpox

    PubMed Central

    Melamed, Sharon; Israely, Tomer; Paran, Nir

    2018-01-01

    Declaration of smallpox eradication by the WHO in 1980 led to discontinuation of the worldwide vaccination campaign. The increasing percentage of unvaccinated individuals, the existence of its causative infectious agent variola virus (VARV), and the recent synthetic achievements increase the threat of intentional or accidental release and reemergence of smallpox. Control of smallpox would require an emergency vaccination campaign, as no other protective measure has been approved to achieve eradication and ensure worldwide protection. Experimental data in surrogate animal models support the assumption, based on anecdotal, uncontrolled historical data, that vaccination up to 4 days postexposure confers effective protection. The long incubation period, and the uncertainty of the exposure status in the surrounding population, call for the development and evaluation of safe and effective methods enabling extension of the therapeutic window, and to reduce the disease manifestations and vaccine adverse reactions. To achieve these goals, we need to evaluate the efficacy of novel and already licensed vaccines as a sole treatment, or in conjunction with immune modulators and antiviral drugs. In this review, we address the available data, recent achievements, and open questions. PMID:29382130

  19. Experimental scattershot boson sampling

    PubMed Central

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J.; Galvão, Ernesto F.; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-01-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy. PMID:26601164

  20. Experimental scattershot boson sampling.

    PubMed

    Bentivegna, Marco; Spagnolo, Nicolò; Vitelli, Chiara; Flamini, Fulvio; Viggianiello, Niko; Latmiral, Ludovico; Mataloni, Paolo; Brod, Daniel J; Galvão, Ernesto F; Crespi, Andrea; Ramponi, Roberta; Osellame, Roberto; Sciarrino, Fabio

    2015-04-01

    Boson sampling is a computational task strongly believed to be hard for classical computers, but efficiently solvable by orchestrated bosonic interference in a specialized quantum computer. Current experimental schemes, however, are still insufficient for a convincing demonstration of the advantage of quantum over classical computation. A new variation of this task, scattershot boson sampling, leads to an exponential increase in speed of the quantum device, using a larger number of photon sources based on parametric down-conversion. This is achieved by having multiple heralded single photons being sent, shot by shot, into different random input ports of the interferometer. We report the first scattershot boson sampling experiments, where six different photon-pair sources are coupled to integrated photonic circuits. We use recently proposed statistical tools to analyze our experimental data, providing strong evidence that our photonic quantum simulator works as expected. This approach represents an important leap toward a convincing experimental demonstration of the quantum computational supremacy.

  1. Experimental results for a 1.5 MW, 110 GHz gyrotron oscillator with reduced mode competition

    NASA Astrophysics Data System (ADS)

    Choi, E. M.; Marchewka, C. D.; Mastovsky, I.; Sirigiri, J. R.; Shapiro, M. A.; Temkin, R. J.

    2006-02-01

    A new result from a 110GHz gyrotron at MIT is reported with an output power of 1.67MW and an efficiency of 42% when operated at 97kV and 41A for 3μs pulses in the TE22,6 mode. These results are a major improvement over results obtained with an earlier cavity design, which produced 1.43MW of power at 37% efficiency. These new results were obtained using a cavity with a reduced output taper angle and a lower ohmic loss when compared with the earlier cavity. The improved operation is shown experimentally to be the result of reduced mode competition from the nearby TE19,7 mode. The reduced mode competition agrees well with an analysis of the startup scenario based on starting current simulations. The present results should prove useful in planning long pulse and CW versions of the 110GHz gyrotron.

  2. Museum-based learning: Informal learning settings and their role in student motivation and achievement in science

    NASA Astrophysics Data System (ADS)

    Holmes, Julie Ann

    This study examined changes in student motivation and achievement in science in relationship with a visit to the IDEA Place Experiment Gallery. The study was based on the pretest-posttest control comparison group design with four treatment groups: control, exhibit, lesson, and exhibit/lesson. The sample was 228 sixth grade students from a public north central Louisiana school who were randomly assigned to one of the four experimental groups. Pretest, posttest, and delayed posttest measures of intrinsic motivation and achievement in science were determined using the Children's Academic Intrinsic Motivation Inventory and an achievement test written to measure areas of science incorporated in the Experiment Gallery exhibits. The data were analyzed using a one way Analysis of Variance (ANOVA), dependent t tests, and Pearson r. Statistical analysis revealed: (a) no significant differences in motivation or achievement on pretest and posttest scores between groups and, (b) no significant relationships between motivation level and achievement between groups on the posttest. Significant differences were found within groups for (a) the lesson group in motivation, and (b) the exhibit group in achievement from pretest to posttest and from posttest to delayed posttest. A significant relationship between level of motivation and science achievement was revealed for the exhibit group on the delayed posttests. There were no other significant findings to support that the effects of the treatment led to any long term effects on motivation or achievement within any of the four experimental groups.

  3. Theory-led confirmation bias and experimental persona

    NASA Astrophysics Data System (ADS)

    Allen, Michael

    2011-04-01

    Questionnaire and interview findings from a survey of three Year 8 (ages 12-13 years) science practical lessons (n = 52) demonstrate how pupils' data collection and inference making were sometimes biased by desires to confirm a personal theory. A variety of behaviours are described where learners knowingly rejected anomalies, manipulated apparatus, invented results or carried out other improper operations to either collect data which they believed were scientifically correct, or achieve social conformity. It is proposed that confirmation bias was a consequence of the degree to which individuals were laden by theory, and driven by this, experimenters assumed one of three different personas: becoming right answer confirmers; good scientists; or indifferent spectators. These personas have parallels with historical instances of scientific behaviour. Implications of a continued teacher-tolerance of pupil confirmation bias include the promotion of unscientific experimenting, and the persistence of unchallenged science misconceptions. Solutions are offered in the way of practical strategies that might reduce experimenters' theory-ladeness.

  4. Study of a vibrating plate: comparison between experimental (ESPI) and analytical results

    NASA Astrophysics Data System (ADS)

    Romero, G.; Alvarez, L.; Alanís, E.; Nallim, L.; Grossi, R.

    2003-07-01

    Real-time electronic speckle pattern interferometry (ESPI) was used for tuning and visualization of natural frequencies of a trapezoidal plate. The plate was excited to resonant vibration by a sinusoidal acoustical source, which provided a continuous range of audio frequencies. Fringe patterns produced during the time-average recording of the vibrating plate—corresponding to several resonant frequencies—were registered. From these interferograms, calculations of vibrational amplitudes by means of zero-order Bessel functions were performed in some particular cases. The system was also studied analytically. The analytical approach developed is based on the Rayleigh-Ritz method and on the use of non-orthogonal right triangular co-ordinates. The deflection of the plate is approximated by a set of beam characteristic orthogonal polynomials generated by using the Gram-Schmidt procedure. A high degree of correlation between computational analysis and experimental results was observed.

  5. Comparing the Achievement of Urban Ninth Graders in Schools Using External Vendors for Whole School Reform

    ERIC Educational Resources Information Center

    Lynch, Virginia N.

    2013-01-01

    Use of external vendors to implement school reform and address student achievement in urban secondary schools has not been studied. This quasi-experimental longitudinal study focused on changes in student achievement among urban 9th grade students during the 2010-2011 school year. The theoretical framework was the transformational model of using…

  6. Preliminary experimental investigation of in vivo magnetic manipulation: results and potential application in hyperthermia.

    PubMed

    Grady, M S; Howard, M A; Molloy, J A; Ritter, R C; Quate, E G; Gillies, G T

    1989-01-01

    The first in vivo experiments in support of a new technique for delivering stereotaxic hyperthermia have been conducted at the Experimental Surgery Facility of the University of Virginia's Medical Center. We call this technique the "Video Tumor Fighter." In each of twelve trials a single, small permanent magnet or train of small permanent magnets was implanted on the brain surface of adult canine models. In three of the trials, this "seed" (typically 6-mm diameter X 6-mm long) was moved by magnetic manipulation to different locations within the brain. In two other trials, the seed moved along the interface between the brain and the inner vault of the skull. The noncontact magnetic manipulation was accomplished by coupling the permanently magnetized seed to the large dc magnetic field gradient created by a water-cooled coil surrounding the animal's head. The seed's motions were monitored with x-ray fluoroscopy; its rate of movement was found to be approximately 0.8 mm s-1. The forces required to produce these motions were on the order of 0.07 N. We document here the instrumentation used in these trials, describe the experimental procedures employed, and discuss the technical aspects of the results.

  7. Counterstereotypic Identity among High-Achieving Black Students

    ERIC Educational Resources Information Center

    Harpalani, Vinay

    2017-01-01

    This article examines how racial stereotypes affect achievement and identity formation among low income, urban Black adolescents. Specifically, the major question addressed is: how do high-achieving Black students succeed academically despite negative stereotypes of their intellectual abilities? Results indicate that high-achieving Black youth,…

  8. A Comparison of Experimental and Theoretical Results for Labyrinth Gas Seals. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Scharrer, Joseph Kirk

    1987-01-01

    The basic equations are derived for a two control volume model for compressible flow in a labyrinth seal. The flow is assumed to be completely turbulent and isoenergetic. The wall friction factors are determined using the Blasius formula. Jet flow theory is used for the calculation of the recirculation velocity in the cavity. Linearized zeroth and first order perturbation equations are developed for small motion about a centered position by an expansion in the eccentricity ratio. The zeroth order pressure distribution is found by satisfying the leakage equation. The circumferential velocity distribution is determined by satisfying the momentum equations. The first order equations are solved by a separation of variable solution. Integration of the resultant pressure distribution along and around the seal defines the reaction force developed by the seal and the corresponding dynamic coefficients. The results of this analysis are compared to experimental test results.

  9. Comparison of simulation and experimental results for a gas puff nozzle on Ambiorix

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Barnier, J-N.; Chevalier, J-M.; Dubroca, B.

    One of source term of Z-Pinch experiments is the gas puff density profile. In order to characterize the gas jet, an experiment based on interferometry has been performed. The first study was a point measurement (a section density profile) which led us to develop a global and instantaneous interferometry imaging method. In order to optimise the nozzle, we simulated the experiment with a flow calculation code (ARES). In this paper, the experimental results are compared with simulations. The different gas properties (He, Ne, Ar) and the flow duration lead us to take care, on the one hand, of the gasmore » viscosity, and on the other, of modifying the code for an instationary flow.« less

  10. PREVAIL: latest electron optics results

    NASA Astrophysics Data System (ADS)

    Pfeiffer, Hans C.; Golladay, Steven D.; Gordon, Michael S.; Kendall, Rodney A.; Lieberman, Jon E.; Rockrohr, James D.; Stickel, Werner; Yamaguchi, Takeshi; Okamoto, Kazuya; Umemoto, Takaaki; Shimizu, Hiroyasu; Kojima, Shinichi; Hamashima, Muneki

    2002-07-01

    The PREVAIL electron optics subsystem developed by IBM has been installed at Nikon's facility in Kumagaya, Japan, for integration into the Nikon commercial EPL stepper. The cornerstone of the electron optics design is the Curvilinear Variable Axis Lens (CVAL) technique originally demonstrated with a proof of concept system. This paper presents the latest experimental results obtained with the electron optical subsystem at Nikon's facility. The results include micrographs illustrating proper CVAL operation through the spatial resolution achieved over the entire optical field of view. They also include data on the most critical issue of the EPL exposure approach: subfield stitching. The methodology of distortion correction will be described and both micrographs and metrology data of stitched subfields will be presented. This paper represents a progress report of the IBM/Nikon alliance activity on EPL.

  11. Identifier mapping performance for integrating transcriptomics and proteomics experimental results

    PubMed Central

    2011-01-01

    Background Studies integrating transcriptomic data with proteomic data can illuminate the proteome more clearly than either separately. Integromic studies can deepen understanding of the dynamic complex regulatory relationship between the transcriptome and the proteome. Integrating these data dictates a reliable mapping between the identifier nomenclature resultant from the two high-throughput platforms. However, this kind of analysis is well known to be hampered by lack of standardization of identifier nomenclature among proteins, genes, and microarray probe sets. Therefore data integration may also play a role in critiquing the fallible gene identifications that both platforms emit. Results We compared three freely available internet-based identifier mapping resources for mapping UniProt accessions (ACCs) to Affymetrix probesets identifications (IDs): DAVID, EnVision, and NetAffx. Liquid chromatography-tandem mass spectrometry analyses of 91 endometrial cancer and 7 noncancer samples generated 11,879 distinct ACCs. For each ACC, we compared the retrieval sets of probeset IDs from each mapping resource. We confirmed a high level of discrepancy among the mapping resources. On the same samples, mRNA expression was available. Therefore, to evaluate the quality of each ACC-to-probeset match, we calculated proteome-transcriptome correlations, and compared the resources presuming that better mapping of identifiers should generate a higher proportion of mapped pairs with strong inter-platform correlations. A mixture model for the correlations fitted well and supported regression analysis, providing a window into the performance of the mapping resources. The resources have added and dropped matches over two years, but their overall performance has not changed. Conclusions The methods presented here serve to achieve concrete context-specific insight, to support well-informed decisions in choosing an ID mapping strategy for "omic" data merging. PMID:21619611

  12. Assessing the Effects of Tutorial and Edutainment Software Programs on Students' Achievements, Misconceptions and Attitudes towards Biology

    ERIC Educational Resources Information Center

    Kara, Yilmaz; Yesilyurt, Selami

    2007-01-01

    The purpose of this study was to investigate the effects of tutorial and edutainment software programs related to "genetic concepts" topic on student achievements, misconceptions and attitudes. An experimental research design including the genetic concepts achievement test (GAT), the genetic concept test (GCT) and biology attitude scale…

  13. A comparison of experimental and theoretical results for leakage, pressure gradients, and rotordynamic coefficients for tapered annular gas seal

    NASA Technical Reports Server (NTRS)

    Elrod, D. A.; Childs, D. W.

    1986-01-01

    A brief review of current annular seal theory and a discussion of the predicted effect on stiffness of tapering the seal stator are presented. An outline of Nelson's analytical-computational method for determining rotordynamic coefficients for annular compressible-flow seals is included. Modifications to increase the maximum rotor speed of an existing air-seal test apparatus at Texas A&M University are described. Experimental results, including leakage, entrance-loss coefficients, pressure distributions, and normalized rotordynamic coefficients, are presented for four convergent-tapered, smooth-rotor, smooth-stator seals. A comparison of the test results shows that an inlet-to-exit clearance ratio of 1.5 to 2.0 provides the maximum direct stiffness, a clearance ratio of 2.5 provides the greatest stability, and a clearance ratio of 1.0 provides the least stability. The experimental results are compared to theoretical results from Nelson's analysis with good agreement. Test results for cross-coupled stiffness show less sensitivity of fluid prerotation than predicted.

  14. Experimental Results From a 2kW Brayton Power Conversion Unit

    NASA Technical Reports Server (NTRS)

    Hervol, David; Mason, Lee; Birchenough, Arthur

    2003-01-01

    This paper presents experimental test results from operation of a 2 kWe Brayton power conversion unit. The Brayton converter was developed for a solar dynamic power system flight experiment planned for the Mir Space Station in 1997. The flight experiment was cancelled, but the converter was tested at Glenn Research Center as part of the Solar Dynamic Ground Test Demonstration system which included a solar concentrator, heat receiver, and space radiator. In preparation for the current testing, the heat receiver was removed and replaced with an electrical resistance heater, simulating the thermal input of a steady-state nuclear source. The converter was operated over a full range of thermal input power levels and rotor speeds to generate an overall performance map. The converter unit will serve as the centerpiece of a Nuclear Electric Propulsion Testbed at Glenn. Future potential uses for the Testbed include high voltage electrical controller development, integrated electric thruster testing and advanced radiator demonstration testing to help guide high power Brayton technology development for Nuclear Electric Propulsion (NEP).

  15. Convergence in parameters and predictions using computational experimental design.

    PubMed

    Hagen, David R; White, Jacob K; Tidor, Bruce

    2013-08-06

    Typically, biological models fitted to experimental data suffer from significant parameter uncertainty, which can lead to inaccurate or uncertain predictions. One school of thought holds that accurate estimation of the true parameters of a biological system is inherently problematic. Recent work, however, suggests that optimal experimental design techniques can select sets of experiments whose members probe complementary aspects of a biochemical network that together can account for its full behaviour. Here, we implemented an experimental design approach for selecting sets of experiments that constrain parameter uncertainty. We demonstrated with a model of the epidermal growth factor-nerve growth factor pathway that, after synthetically performing a handful of optimal experiments, the uncertainty in all 48 parameters converged below 10 per cent. Furthermore, the fitted parameters converged to their true values with a small error consistent with the residual uncertainty. When untested experimental conditions were simulated with the fitted models, the predicted species concentrations converged to their true values with errors that were consistent with the residual uncertainty. This paper suggests that accurate parameter estimation is achievable with complementary experiments specifically designed for the task, and that the resulting parametrized models are capable of accurate predictions.

  16. Analysis of experimental results of the inlet for the NASA hypersonic research engine aerothermodynamic integration model. [wind tunnel tests of ramjet engine hypersonic inlets

    NASA Technical Reports Server (NTRS)

    Andrews, E. H., Jr.; Mackley, E. A.

    1976-01-01

    An aerodynamic engine inlet analysis was performed on the experimental results obtained at nominal Mach numbers of 5, 6, and 7 from the NASA Hypersonic Research Engine (HRE) Aerothermodynamic Integration Model (AIM). Incorporation on the AIM of the mixed-compression inlet design represented the final phase of an inlet development program of the HRE Project. The purpose of this analysis was to compare the AIM inlet experimental results with theoretical results. Experimental performance was based on measured surface pressures used in a one-dimensional force-momentum theorem. Results of the analysis indicate that surface static-pressure measurements agree reasonably well with theoretical predictions except in the regions where the theory predicts large pressure discontinuities. Experimental and theoretical results both based on the one-dimensional force-momentum theorem yielded inlet performance parameters as functions of Mach number that exhibited reasonable agreement. Previous predictions of inlet unstart that resulted from pressure disturbances created by fuel injection and combustion appeared to be pessimistic.

  17. Aqueous ionic liquids and their effects on protein structures: an overview on recent theoretical and experimental results

    NASA Astrophysics Data System (ADS)

    Smiatek, Jens

    2017-06-01

    Ionic liquids (ILs) are used in a variety of technological and biological applications. Recent experimental and simulation results reveal the influence of aqueous ionic liquids on the stability of protein and enzyme structures. Depending on different parameters like the concentration and the ion composition, one can observe distinct stabilization or denaturation mechanisms for various ILs. In this review, we summarize the main findings and discuss the implications with regard to molecular theories of solutions and specific ion effects. A preferential binding model is introduced in order to discuss protein-IL effects from a statistical mechanics perspective. The value of the preferential binding coefficient determines the strength of the ion influence and indicates a shift of the chemical equilibrium either to the native or the denatured state of the protein. We highlight the role of water in order to explain the self-association behavior of the IL species and discuss recent experimental and simulation results in the light of the observed binding effects.

  18. The mzTab data exchange format: communicating mass-spectrometry-based proteomics and metabolomics experimental results to a wider audience.

    PubMed

    Griss, Johannes; Jones, Andrew R; Sachsenberg, Timo; Walzer, Mathias; Gatto, Laurent; Hartler, Jürgen; Thallinger, Gerhard G; Salek, Reza M; Steinbeck, Christoph; Neuhauser, Nadin; Cox, Jürgen; Neumann, Steffen; Fan, Jun; Reisinger, Florian; Xu, Qing-Wei; Del Toro, Noemi; Pérez-Riverol, Yasset; Ghali, Fawaz; Bandeira, Nuno; Xenarios, Ioannis; Kohlbacher, Oliver; Vizcaíno, Juan Antonio; Hermjakob, Henning

    2014-10-01

    The HUPO Proteomics Standards Initiative has developed several standardized data formats to facilitate data sharing in mass spectrometry (MS)-based proteomics. These allow researchers to report their complete results in a unified way. However, at present, there is no format to describe the final qualitative and quantitative results for proteomics and metabolomics experiments in a simple tabular format. Many downstream analysis use cases are only concerned with the final results of an experiment and require an easily accessible format, compatible with tools such as Microsoft Excel or R. We developed the mzTab file format for MS-based proteomics and metabolomics results to meet this need. mzTab is intended as a lightweight supplement to the existing standard XML-based file formats (mzML, mzIdentML, mzQuantML), providing a comprehensive summary, similar in concept to the supplemental material of a scientific publication. mzTab files can contain protein, peptide, and small molecule identifications together with experimental metadata and basic quantitative information. The format is not intended to store the complete experimental evidence but provides mechanisms to report results at different levels of detail. These range from a simple summary of the final results to a representation of the results including the experimental design. This format is ideally suited to make MS-based proteomics and metabolomics results available to a wider biological community outside the field of MS. Several software tools for proteomics and metabolomics have already adapted the format as an output format. The comprehensive mzTab specification document and extensive additional documentation can be found online. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  19. Effects of Mastery Learning Approach on Secondary School Students' Physics Achievement

    ERIC Educational Resources Information Center

    Wambugu, Patriciah W.; Changeiywo, Johnson M.

    2008-01-01

    This study aimed at finding out the effects of Mastery Learning Approach (MLA) on students' achievement in Physics. The study was Quasi-experimental and Solomon Four Non-equivalent Control Group Design was used. The target population comprised of secondary school students in Kieni East Division of Nyeri District. The accessible population was Form…

  20. Effects of Graphic Organiser on Students' Achievement in Algebraic Word Problems

    ERIC Educational Resources Information Center

    Owolabi, Josiah; Adaramati, Tobiloba Faith

    2015-01-01

    This study investigated the effects of graphic organiser and gender on students' academic achievement in algebraic word problem. Three research questions and three null hypotheses were used in guiding this study. Quasi experimental research was employed and Non-equivalent pre and post test design was used. The study involved the Senior Secondary…

  1. The Effect of Mobile Learning on Students' Achievement and Conversational Skills

    ERIC Educational Resources Information Center

    Elfeky, Abdellah Ibrahim Mohammed; Masadeh, Thouqan Saleem Yakoub

    2016-01-01

    The present study aimed to examine the effect of Mobile Learning, which is a kind of E-learning that uses mobile devices, on the development of the academic achievement and conversational skills of English language specialty students at Najran University. The study used the quasi-experimental approach. Participants consisted of (50) students who…

  2. Experimental Evaluations of Elementary Science Programs: A Best-Evidence Synthesis

    ERIC Educational Resources Information Center

    Slavin, Robert E.; Lake, Cynthia; Hanley, Pam; Thurston, Allen

    2014-01-01

    This article presents a systematic review of research on the achievement outcomes of all types of approaches to teaching science in elementary schools. Study inclusion criteria included use of randomized or matched control groups, a study duration of at least 4 weeks, and use of achievement measures independent of the experimental treatment. A…

  3. Surface electromagnetic waves in Fibonacci superlattices: Theoretical and experimental results

    NASA Astrophysics Data System (ADS)

    El Hassouani, Y.; Aynaou, H.; El Boudouti, E. H.; Djafari-Rouhani, B.; Akjouj, A.; Velasco, V. R.

    2006-07-01

    We study theoretically and experimentally the existence and behavior of the localized surface modes in one-dimensional (1D) quasiperiodic photonic band gap structures. These structures are made of segments and loops arranged according to a Fibonacci sequence. The experiments are carried out by using coaxial cables in the frequency region of a few tens of MHz. We consider 1D periodic structures (superlattice) where each cell is a well-defined Fibonacci generation. In these structures, we generalize a theoretical rule on the surface modes, namely when one considers two semi-infinite superlattices obtained by the cleavage of an infinite superlattice, it exists exactly one surface mode in each gap. This mode is localized on the surface either of one or the other semi-infinite superlattice. We discuss the existence of various types of surface modes and their spatial localization. The experimental observation of these modes is carried out by measuring the transmission through a guide along which a finite superlattice (i.e., constituted of a finite number of quasiperiodic cells) is grafted vertically. The surface modes appear as maxima of the transmission spectrum. These experiments are in good agreement with the theoretical model based on the formalism of the Green function.

  4. Low Dimensional Non-Crystallographic Metallic Nanostructures:. HRTEM Simulation, Models and Experimental Results

    NASA Astrophysics Data System (ADS)

    Rodríguez-López, J. L.; Montejano-Carrizales, J. M.; José-Yacamán, M.

    Modern nanoparticle research in the field of small metallic systems has confirmed that many nanoparticles take on some Platonic and Archimedean solids related shapes. A Platonic solid looks the same from any vertex, and intuitively they appear as good candidates for atomic equilibrium shapes. A very clear example is the icosahedral (Ih) particle that only shows {111} faces that contribute to produce a more rounded structure. Indeed, many studies report the Ih as the most stable particle at the size range r≤20 Å for noble gases and for some metals. In this review, we report on the structure and shape of mono- and bimetallic nanoparticles in the wide size range from 1-300 nm. First, we present AuPd nanoparticles in the 1-2 nm size range that show dodecahedral atomic growth packing, one of the Platonic solid shapes that have not been identified before in this small size range for metallic particles. Next, with particles in the size range of 2-5 nm, we present an energetic surface reconstruction phenomenon observed also on bimetallic nanoparticle systems of AuPd and AuCu, similar to a re-solidification effect observed during cooling process in lead clusters. These binary alloy nanoparticles show the fivefold edges truncated, resulting in {100} faces on decahedral structures, an effect largely envisioned and reported theoretically, with no experimental evidence in the literature before. Next nanostructure we review is a monometallic system in the size range of ≈5 nm that we termed the decmon. We present here some detailed geometrical analysis and experimental evidence that supports our models. Finally, in the size range of 100-300 nm, we present icosahedrally derived star gold nanocrystals which resembles the great stellated dodechaedron, which is a Kepler-Poisont solid. We conclude then that the shape or morphology of some mono- and bimetallic particles evolves with size following the sequence from atoms to the Platonic solids, and with a slightly greater particle

  5. The effects of three concept mapping strategies on seventh-grade students' science achievement at an urban middle school

    NASA Astrophysics Data System (ADS)

    Dosanjh, Navdeep Kaur

    2011-12-01

    There is great concern over students' poor science achievement in the United States. Due to the lack of science achievement, students are not pursing science related careers resulting in an increase in outsourcing to other countries. Learning strategies such as concept mapping may ameliorate this situation by providing students with tools that encourage meaningful learning. The purpose of this quasi-experimental study was to measure the effects of three concept mapping learning strategies (concept identifying, proposition identifying, student generated) on urban middle school students' understanding of the circulatory system. Three intact classes of seventh-grade students were assigned to one of the three concept mapping strategies. The students were given a pretest on the circulatory system then learned and used their respective concept mapping strategies while learning about the circulatory system. At the conclusion of the study, students' science achievement was measured by performance on an achievement test and rubric scores of their respective concept identifying, proposition identifying, and student generated concept maps. The results of the study suggest that all three of the concept mapping strategies are effective in increasing students' science achievement. Additionally, the moderate significant correlations between the posttest and concept map scores of the current study established that concept maps are a useful measure of student knowledge. Lastly, the results of the current study also suggest that the concept identifying mapping strategy may be a useful scaffold in instructing students how to develop student generated concept maps.

  6. Experimental Study of an Advanced Concept of Moderate-resolution Holographic Spectrographs

    NASA Astrophysics Data System (ADS)

    Muslimov, Eduard; Valyavin, Gennady; Fabrika, Sergei; Musaev, Faig; Galazutdinov, Gazinur; Pavlycheva, Nadezhda; Emelianov, Eduard

    2018-07-01

    We present the results of an experimental study of an advanced moderate-resolution spectrograph based on a cascade of narrow-band holographic gratings. The main goal of the project is to achieve a moderately high spectral resolution with R up to 5000 simultaneously in the 4300–6800 Å visible spectral range on a single standard CCD, together with an increased throughput. The experimental study consisted of (1) resolution and image quality tests performed using the solar spectrum, and (2) a total throughput test performed for a number of wavelengths using a calibrated lab monochromator. The measured spectral resolving power reaches values over R > 4000 while the experimental throughput is as high as 55%, which agrees well with the modeling results. Comparing the obtained characteristics of the spectrograph under consideration with the best existing spectrographs, we conclude that the used concept can be considered as a very competitive and cheap alternative to the existing spectrographs of the given class. We propose several astrophysical applications for the instrument and discuss the prospect of creating its full-scale version.

  7. The influence of achievement goals on the constructive activity of low achievers during collaborative problem solving.

    PubMed

    Gabriele, Anthony J

    2007-03-01

    Previous research on small-group learning has found that level of constructive activity (solving or explaining how to solve problems using ideas stated or implied in the explanation provided by a partner) was a better predictor of post-test achievement than either a student's prior achievement or the quality of help received (Webb, Troper, & Fall, 1995). The purpose of this study was to extend this research by examining the influence of additional factors, in particular, achievement goals and comprehension monitoring, on low achieving students' constructive activity after receiving help from a high achieving peer. Thirty-two low achieving upper elementary students from an urban school district in the mid-west of the United States were paired with high achieving partners. Videotape data from a previously reported study on peer collaboration were transcribed and reanalyzed. In that study, dyads were randomly assigned instructions designed to induce either a learning or performance goal and were videotaped as they worked together to solve a set of mathematical word problems. The following day, students were individually post-tested on problems similar to the ones worked on in pairs. Consistent with previous research, low achieving students' level of constructive activity predicted post-test performance. In addition, constructive activity was found to mediate the relationship between achievement goals and learning. However, achievement goals were not related to low achievers constructive use of help. Instead, achievement goals were related to low achievers' relative accuracy in comprehension monitoring, which in turn was related to level of constructive activity. The meaning of these results for understanding the processes by which low achievers learn from peer help and implications for classroom practice are discussed.

  8. Experimental characterization of active plasma lensing for electron beams

    NASA Astrophysics Data System (ADS)

    Pompili, R.; Anania, M. P.; Bellaveglia, M.; Biagioni, A.; Bini, S.; Bisesto, F.; Brentegani, E.; Castorina, G.; Chiadroni, E.; Cianchi, A.; Croia, M.; Di Giovenale, D.; Ferrario, M.; Filippi, F.; Giribono, A.; Lollo, V.; Marocchino, A.; Marongiu, M.; Mostacci, A.; Di Pirro, G.; Romeo, S.; Rossi, A. R.; Scifo, J.; Shpakov, V.; Vaccarezza, C.; Villa, F.; Zigler, A.

    2017-03-01

    The active plasma lens represents a compact and affordable tool with radially symmetric focusing and field gradients up to several kT/m. In order to be used as a focusing device, its effects on the particle beam distribution must be well characterized. Here, we present the experimental results obtained by focusing an high-brightness electron beam by means of a 3 cm-long discharge-capillary pre-filled with Hydrogen gas. We achieved minimum spot sizes of 24 μ m (rms) showing that, during plasma lensing, the beam emittance increases due to nonlinearities in the focusing field. The results have been cross-checked with numerical simulations, showing an excellent agreement.

  9. Experimental comparison of symmetry in rugby and cylindrical holhraums

    NASA Astrophysics Data System (ADS)

    Philippe, Franck; Tassin, Veronique; Laffite, Stephane; Monteil, Marie-Christine; Bastian, Josiane; Lours, Laurence; Villette, Bruno; Stemmler, Philippe; Bednarczyk, Sophie; Reneaume, Benoit; di Nicola, Pascale; Raffin, Vincent

    2007-11-01

    Recently, holhraum shape optimization has been investigated as a practical way to achieve ignition at lower energy [1][2]. Rugby shaped holhraums theoretically allow better energetic coupling and symmetry control than classical cylinders. As a first step toward an experimental validation of this design, this talk presents the results of experiments on the OMEGA laser facility dedicated to the comparison of symmetry in cylindrical and rugby holhraums. Foamball radiographs and Symcaps emission contours for both type of holhraums are compared to numerical simulation results. [1] M. Vandenboomgaerde et al., accepted by Phys. Rev. Lett. [2] P. Amendt et al., Phys. Plasmas 14, 056312 (2007)

  10. Comparing the Impacts of Tutorial and Edutainment Software Programs on Students' Achievements, Misconceptions, and Attitudes towards Biology

    ERIC Educational Resources Information Center

    Kara, Yilmaz; Yesilyurt, Selami

    2008-01-01

    The purpose of this study was to investigate the effects of tutorial and edutainment design of instructional software programs related to the "cell division" topic on student achievements, misconceptions and attitudes. An experimental research design including the cell division achievement test (CAT), the cell division concept test (CCT) and…

  11. The effects of computer-simulated experiments on high school biology students' problem-solving skills and achievement

    NASA Astrophysics Data System (ADS)

    Carmack, Gay Lynn Dickinson

    2000-10-01

    This two-part quasi-experimental repeated measures study examined whether computer simulated experiments have an effect on the problem solving skills of high school biology students in a school-within-a-school magnet program. Specifically, the study identified episodes in a simulation sequence where problem solving skills improved. In the Fall academic semester, experimental group students (n = 30) were exposed to two simulations: CaseIt! and EVOLVE!. Control group students participated in an internet research project and a paper Hardy-Weinberg activity. In the Spring academic semester, experimental group students were exposed to three simulations: Genetics Construction Kit, CaseIt! and EVOLVE! . Spring control group students participated in a Drosophila lab, an internet research project, and Advanced Placement lab 8. Results indicate that the Fall and Spring experimental groups experienced significant gains in scientific problem solving after the second simulation in the sequence. These gains were independent of the simulation sequence or the amount of time spent on the simulations. These gains were significantly greater than control group scores in the Fall. The Spring control group significantly outscored all other study groups on both pretest measures. Even so, the Spring experimental group problem solving performance caught up to the Spring control group performance after the third simulation. There were no significant differences between control and experimental groups on content achievement. Results indicate that CSE is as effective as traditional laboratories in promoting scientific problem solving and that CSE is a useful tool for improving students' scientific problem solving skills. Moreover, retention of problem solving skills is enhanced by utilizing more than one simulation.

  12. Experimental evaluation and thermodynamic system modeling of thermoelectric heat pump clothes dryer

    DOE PAGES

    Patel, Viral K.; Gluesenkamp, Kyle R.; Goodman, Dakota; ...

    2018-02-28

    Electric clothes dryers consume about 6% of US residential electricity consumption. Using a solid-state technology without refrigerant, thermoelectric (TE) heat pump dryers have the potential to be more efficient than units based on electric resistance and less expensive than units based on vapor compression. This study presents a steady state TE dryer model, and validates the model against results from an experimental prototype. The system model is composed of a TE heat pump element model coupled with a psychrometric dryer sub-model. Experimental results had energy factors (EFs) of up to 2.95 kg of dry cloth per kWh (6.51 lb c/kWh),more » with a dry time of 159 min. A faster dry time of 96 min was also achieved at an EF of 2.54 kg c/kWh (5.60 lb c/kWh). The model was able to replicate the experimental results within 5% of EF and 5% of dry time values. Finally, the results are used to identify important parameters that affect dryer performance, such as relative humidity of air leaving the drum.« less

  13. Experimental evaluation and thermodynamic system modeling of thermoelectric heat pump clothes dryer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Patel, Viral K.; Gluesenkamp, Kyle R.; Goodman, Dakota

    Electric clothes dryers consume about 6% of US residential electricity consumption. Using a solid-state technology without refrigerant, thermoelectric (TE) heat pump dryers have the potential to be more efficient than units based on electric resistance and less expensive than units based on vapor compression. This study presents a steady state TE dryer model, and validates the model against results from an experimental prototype. The system model is composed of a TE heat pump element model coupled with a psychrometric dryer sub-model. Experimental results had energy factors (EFs) of up to 2.95 kg of dry cloth per kWh (6.51 lb c/kWh),more » with a dry time of 159 min. A faster dry time of 96 min was also achieved at an EF of 2.54 kg c/kWh (5.60 lb c/kWh). The model was able to replicate the experimental results within 5% of EF and 5% of dry time values. Finally, the results are used to identify important parameters that affect dryer performance, such as relative humidity of air leaving the drum.« less

  14. Experimental Investigation of a High Pressure Ratio Aspirated Fan Stage

    NASA Technical Reports Server (NTRS)

    Merchant, Ali; Kerrebrock, Jack L.; Adamczyk, John J.; Braunscheidel, Edward

    2004-01-01

    The experimental investigation of an aspirated fan stage designed to achieve a pressure ratio of 3.4:1 at 1500 ft/sec is presented in this paper. The low-energy viscous flow is aspirated from diffusion-limiting locations on the blades and flowpath surfaces of the stage, enabling a very high pressure ratio to be achieved in a single stage. The fan stage performance was mapped at various operating speeds from choke to stall in a compressor facility at fully simulated engine conditions. The experimentally determined stage performance, in terms of pressure ratio and corresponding inlet mass flow rate, was found to be in good agreement with the three-dimensional viscous computational prediction, and in turn close to the design intent. Stage pressure ratios exceeding 3:1 were achieved at design speed, with an aspiration flow fraction of 3.5 percent of the stage inlet mass flow. The experimental performance of the stage at various operating conditions, including detailed flowfield measurements, are presented and discussed in the context of the computational analyses. The sensitivity of the stage performance and operability to reduced aspiration flow rates at design and off design conditions are also discussed.

  15. Classroom Instruction and Science Achievement in Japan, Hong Kong, and Chinese Taipei: Results from the TIMSS 1999 Assessment

    ERIC Educational Resources Information Center

    House, J. Daniel

    2005-01-01

    The Third International Mathematics and Science Study represents the most comprehensive international assessment of educational contexts and student achievement yet conducted. As part of the examination of the effects of contextual factors on student achievement, a model was constructed that considered the effects of variables such as…

  16. Experimental Identification and Characterization of Multirotor UAV Propulsion

    NASA Astrophysics Data System (ADS)

    Kotarski, Denis; Krznar, Matija; Piljek, Petar; Simunic, Nikola

    2017-07-01

    In this paper, an experimental procedure for the identification and characterization of multirotor Unmanned Aerial Vehicle (UAV) propulsion is presented. Propulsion configuration needs to be defined precisely in order to achieve required flight performance. Based on the accurate dynamic model and empirical measurements of multirotor propulsion physical parameters, it is possible to design diverse configurations with different characteristics for various purposes. As a case study, we investigated design considerations for a micro indoor multirotor which is suitable for control algorithm implementation in structured environment. It consists of open source autopilot, sensors for indoor flight, “take off the shelf” propulsion components and frame. The series of experiments were conducted to show the process of parameters identification and the procedure for analysis and propulsion characterization. Additionally, we explore battery performance in terms of mass and specific energy. Experimental results show identified and estimated propulsion parameters through which blade element theory is verified.

  17. Design and experimental evaluation of robust controllers for a two-wheeled robot

    NASA Astrophysics Data System (ADS)

    Kralev, J.; Slavov, Ts.; Petkov, P.

    2016-11-01

    The paper presents the design and experimental evaluation of two alternative μ-controllers for robust vertical stabilisation of a two-wheeled self-balancing robot. The controllers design is based on models derived by identification from closed-loop experimental data. In the first design, a signal-based uncertainty representation obtained directly from the identification procedure is used, which leads to a controller of order 29. In the second design the signal uncertainty is approximated by an input multiplicative uncertainty, which leads to a controller of order 50, subsequently reduced to 30. The performance of the two μ-controllers is compared with the performance of a conventional linear quadratic controller with 17th-order Kalman filter. A proportional-integral controller of the rotational motion around the vertical axis is implemented as well. The control code is generated using Simulink® controller models and is embedded in a digital signal processor. Results from the simulation of the closed-loop system as well as experimental results obtained during the real-time implementation of the designed controllers are given. The theoretical investigation and experimental results confirm that the closed-loop system achieves robust performance in respect to the uncertainties related to the identified robot model.

  18. COMPUTATIONAL MODELING AND EXPERIMENTAL STUDIES ON NOx REDUCTION UNDER PULVERIZED COAL COMBUSTION CONDITIONS

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Subha K. Kumpaty; Kannikeswaran Subramanian; Victor P. Nokku

    1998-06-01

    In this work, both computer simulation and experimental studies were conducted to investigate several strategies for NO{sub x} reduction under pulverized coal combustion conditions with an aim to meet the stringent environmental standards for NO{sub x} control. Both computer predictions and reburning experiments yielded favorable results in terms of NO{sub x} control by reburning with a combination of methane and acetylene as well as non-selective catalytic reduction of NO{sub x} with ammonia following reburning with methane. The greatest reduction was achieved at the reburning stoichiometric ratio of 0.9; the reduction was very significant, as clearly shown in Chapters III andmore » V. Both the experimental and computational results favored mixing gases: methane and acetylene (90% and 10% respectively) and methane and ammonia (98% and 2%) in order to get optimum reduction levels which can not be achieved by individual gases at any amounts. Also, the above gaseous compositions as reburning fuels seemed to have a larger window of stoichiometric ratio (SR2 < 0.9) as opposed to just methane (SR2=0.9) so as to reduce and keep NO{sub x} at low ppm levels. From the various computational runs, it has been observed that although there are several pathways that contribute to NO{sub x} reduction, the key pathway is NO {r_arrow} HCN {r_arrow} NH{sub 3} {r_arrow} N{sub 2} + H{sub 2}. With the trends established in this work, it is possible to scale the experimental results to real time industrial applications using computational calculations.« less

  19. PBL in Teacher Education: Its Effects on Achievement and Self-Regulation

    ERIC Educational Resources Information Center

    Erdogan, Tolga; Senemoglu, Nuray

    2017-01-01

    Problem-based learning (PBL) as an educational practice continues to have great impact on all levels of education and across different disciplines. The aim of this experimental study is to examine the effects of PBL on prospective teachers' academic achievements and self-regulation. The treatment group (n = 36) and the control group (n = 21)…

  20. Humorous Videos and Idiom Achievement: Some Pedagogical Considerations for EFL Learners

    ERIC Educational Resources Information Center

    Neissari, Malihe; Ashraf, Hamid; Ghorbani, Mohammad Reza

    2017-01-01

    Employing a quasi-experimental design, this study examined the efficacy of humorous idiom video clips on the achievement of Iranian undergraduate students studying English as a Foreign Language (EFL). Forty humorous video clips from the English Idiom Series called "The Teacher" from the BBC website were used to teach 120 idioms to 61…

  1. The Effect of Concept Mapping on Students' Learning Achievements and Interests

    ERIC Educational Resources Information Center

    Chiou, Chei-Chang

    2008-01-01

    The study described in this paper has examined whether concept mapping can be used to help students to improve their learning achievement and interests. The participants were 124 students from two classes enrolled in an advanced accounting course at the School of Management of a university in Taiwan. The experimental data revealed two important…

  2. The implementation of discovery learning model based on lesson study to increase student's achievement in colloid

    NASA Astrophysics Data System (ADS)

    Suyanti, Retno Dwi; Purba, Deby Monika

    2017-03-01

    The objectives of this research are to get the increase student's achievement on the discovery learning model based on lesson study. Beside of that, this research also conducted to know the cognitive aspect. This research was done in three school that are SMA N 3 Medan. Population is all the students in SMA N 11 Medan which taken by purposive random sampling. The research instruments are achievement test instruments that have been validated. The research data analyzed by statistic using Ms Excell. The result data shows that the student's achievement taught by discovery learning model based on Lesson study higher than the student's achievement taught by direct instructional method. It can be seen from the average of gain and also proved with t-test, the normalized gain in experimental class of SMA N 11 is (0.74±0.12) and control class (0.45±0.12), at significant level α = 0.05, Ha is received and Ho is refused where tcount>ttable in SMA N 11 (9.81>1,66). Then get the improvement cognitive aspect from three of school is C2 where SMA N 11 is 0.84(high). Then the observation sheet result of lesson study from SMA N 11 92 % of student working together while 67% less in active using media.

  3. Relationship between the Wide Range Achievement Test 3 and the Wechsler Individual Achievement Test.

    PubMed

    Smith, T D; Smith, B L

    1998-12-01

    The present study examined the relationship between the Wide Range Achievement Test 3 and the Wechsler Individual Achievement Test for a sample of children with learning disabilities in two rural school districts. Data were collected for 87 school children who had been classified as learning disabled and placed in special education resource services. Pearson product-moment correlations between scores on the two measures were significant and moderate to high; however, mean scores were not significantly different on Reading, Spelling, and Arithmetic subtests of the Wide Range Achievement Test 3 compared to those for the basic Reading, Spelling, and Mathematics Reasoning subtests of the Wechsler Individual Achievement Test. Although there were significant mean differences between scores on Reading and Reading Comprehension and on Arithmetic and Numerical Operations, magnitudes were small. It appears that the two tests provide similar results when screening for reading, spelling, and arithmetic.

  4. Achieving diffraction-limited nanometer-scale X-ray point focus with two crossed multilayer Laue lenses: alignment challenges

    DOE PAGES

    Yan, Hanfei; Huang, Xiaojing; Bouet, Nathalie; ...

    2017-10-16

    In this article, we discuss misalignment-induced aberrations in a pair of crossed multilayer Laue lenses used for achieving a nanometer-scale x-ray point focus. We thoroughly investigate the impacts of two most important contributions, the orthogonality and the separation distance between two lenses. We find that misalignment in the orthogonality results in astigmatism at 45º and other inclination angles when coupled with a separation distance error. Theoretical explanation and experimental verification are provided. We show that to achieve a diffraction-limited point focus, accurate alignment of the azimuthal angle is required to ensure orthogonality between two lenses, and the required accuracy ismore » scaled with the ratio of the focus size to the aperture size.« less

  5. Numerical and experimental evaluation of microfluidic sorting devices.

    PubMed

    Taylor, Jay K; Ren, Carolyn L; Stubley, G D

    2008-01-01

    The development of lab-on-a-chip devices calls for the isolation or separation of specific bioparticles or cells. The design of a miniaturized cell-sorting device for handheld operation must follow the strict parameters associated with lab-on-a-chip technology. The limitations include applied voltage, high efficiency of cell-separation, reliability, size, flow control, and cost, among others. Currently used designs have achieved successful levels of cell isolation; however, further improvements in the microfluidic chip design are important to incorporate into larger systems. This study evaluates specific design modifications that contribute to the reduction of required applied potential aiming for developing portable devices, improved operation reliability by minimizing induced pressure disturbance when electrokinetic pumping is employed, and improved flow control by incorporating directing streams achieving dynamic sorting and counting. The chip designs fabricated in glass and polymeric materials include asymmetric channel widths for sample focusing, nonuniform channel depth for minimizing induced pressure disturbance, directing streams to assist particle flow control, and online filters for reducing channel blockage. Fluorescence-based visualization experimental results of electrokinetic focusing, flow field phenomena, and dynamic sorting demonstrate the advantages of the chip design. Numerical simulations in COMSOL are validated by the experimental data and used to investigate the effects of channel geometry and fluid properties on the flow field.

  6. An experimental investigation of gapwise periodicity and unsteady aerodynamic response in an oscillating cascade. 1: Experimental and theoretical results. [turbine blades

    NASA Technical Reports Server (NTRS)

    Carta, F. O.

    1982-01-01

    Tests were conducted on a linear cascade of airfoils oscillating in pitch to measure the unsteady pressure response on selected blades along the leading edge plane of the cascade, over the chord of the center blade, and on the sidewall in the plane of the leading edge. The pressure data were reduced to Fourier coefficient form for direct comparison, and were also processed to yield integrated loads and, particularly, the aerodynamic damping coefficient. Results from the unsteady Verdon/Caspar theory for cascaded blades with nonzero thickness and camber were compared with the experimental measurements. The three primary results are: (1) from the leading edge plane blade data, the cascade was judged to be periodic in unsteady flow over the range of parameters tested; (2) the interblade phase angle was found to be the single most important parameter affecting the stability of the oscillating cascade blades; and (3) the real blade theory and the experiment were in excellent agreement for the several cases chosen for comparison.

  7. A Multigrade, Multiyear Statewide Examination of Reading Achievement: Examination of Reading Achievement Examining Variability between Districts, Schools, and Students

    ERIC Educational Resources Information Center

    Adelson, Jill L.; Dickinson, Emily R.; Cunningham, Brittany C.

    2016-01-01

    This brief examined the patterns of reading achievement using statewide data from all students (Grades 3-10) in multiple years to examine gaps based on student, school, and district characteristics. Results indicate reading achievement varied most between students within schools and that students' prior achievement was the strongest predictor of…

  8. The School Climate-Student Achievement Connection: If We Want Achievement Gains, We Need to Begin by Improving the Climate

    ERIC Educational Resources Information Center

    Shindler, John; Jones, Albert; Williams, A. Dee; Taylor, Clint; Cardenas, Hermenia

    2016-01-01

    This study examined the relationship between school climate and student achievement ratings in urban school districts in five states (N = 230). Many educators view school climate and student achievement as separate considerations. However the results of this study suggest that climate and student achievement were highly related. In fact, the…

  9. Computer-Based Training in Math and Working Memory Improves Cognitive Skills and Academic Achievement in Primary School Children: Behavioral Results

    PubMed Central

    Sánchez-Pérez, Noelia; Castillo, Alejandro; López-López, José A.; Pina, Violeta; Puga, Jorge L.; Campoy, Guillermo; González-Salinas, Carmen; Fuentes, Luis J.

    2018-01-01

    Student academic achievement has been positively related to further development outcomes, such as the attainment of higher educational, employment, and socioeconomic aspirations. Among all the academic competences, mathematics has been identified as an essential skill in the field of international leadership as well as for those seeking positions in disciplines related to science, technology, and engineering. Given its positive consequences, studies have designed trainings to enhance children's mathematical skills. Additionally, the ability to regulate and control actions and cognitions, i.e., executive functions (EF), has been associated with school success, which has resulted in a strong effort to develop EF training programs to improve students' EF and academic achievement. The present study examined the efficacy of a school computer-based training composed of two components, namely, working memory and mathematics tasks. Among the advantages of using a computer-based training program is the ease with which it can be implemented in school settings and the ease by which the difficulty of the tasks can be adapted to fit the child's ability level. To test the effects of the training, children's cognitive skills (EF and IQ) and their school achievement (math and language grades and abilities) were evaluated. The results revealed a significant improvement in cognitive skills, such as non-verbal IQ and inhibition, and better school performance in math and reading among the children who participated in the training compared to those children who did not. Most of the improvements were related to training on WM tasks. These findings confirmed the efficacy of a computer-based training that combined WM and mathematics activities as part of the school routines based on the training's impact on children's academic competences and cognitive skills. PMID:29375442

  10. Computer-Based Training in Math and Working Memory Improves Cognitive Skills and Academic Achievement in Primary School Children: Behavioral Results.

    PubMed

    Sánchez-Pérez, Noelia; Castillo, Alejandro; López-López, José A; Pina, Violeta; Puga, Jorge L; Campoy, Guillermo; González-Salinas, Carmen; Fuentes, Luis J

    2017-01-01

    Student academic achievement has been positively related to further development outcomes, such as the attainment of higher educational, employment, and socioeconomic aspirations. Among all the academic competences, mathematics has been identified as an essential skill in the field of international leadership as well as for those seeking positions in disciplines related to science, technology, and engineering. Given its positive consequences, studies have designed trainings to enhance children's mathematical skills. Additionally, the ability to regulate and control actions and cognitions, i.e., executive functions (EF), has been associated with school success, which has resulted in a strong effort to develop EF training programs to improve students' EF and academic achievement. The present study examined the efficacy of a school computer-based training composed of two components, namely, working memory and mathematics tasks. Among the advantages of using a computer-based training program is the ease with which it can be implemented in school settings and the ease by which the difficulty of the tasks can be adapted to fit the child's ability level. To test the effects of the training, children's cognitive skills (EF and IQ) and their school achievement (math and language grades and abilities) were evaluated. The results revealed a significant improvement in cognitive skills, such as non-verbal IQ and inhibition, and better school performance in math and reading among the children who participated in the training compared to those children who did not. Most of the improvements were related to training on WM tasks. These findings confirmed the efficacy of a computer-based training that combined WM and mathematics activities as part of the school routines based on the training's impact on children's academic competences and cognitive skills.

  11. Experimental and computational investigation of Morse taper conometric system reliability for the definition of fixed connections between dental implants and prostheses.

    PubMed

    Bressan, Eriberto; Lops, Diego; Tomasi, Cristiano; Ricci, Sara; Stocchero, Michele; Carniel, Emanuele Luigi

    2014-07-01

    Nowadays, dental implantology is a reliable technique for treatment of partially and completely edentulous patients. The achievement of stable dentition is ensured by implant-supported fixed dental prostheses. Morse taper conometric system may provide fixed retention between implants and dental prostheses. The aim of this study was to investigate retentive performance and mechanical strength of a Morse taper conometric system used as implant-supported fixed dental prostheses retention. Experimental and finite element investigations were performed. Experimental tests were achieved on a specific abutment-coping system, accounting for both cemented and non-cemented situations. The results from the experimental activities were processed to identify the mechanical behavior of the coping-abutment interface. Finally, the achieved information was applied to develop reliable finite element models of different abutment-coping systems. The analyses were developed accounting for different geometrical conformations of the abutment-coping system, such as different taper angle. The results showed that activation process, occurred through a suitable insertion force, could provide retentive performances equal to a cemented system without compromising the mechanical functionality of the system. These findings suggest that Morse taper conometrical system can provide a fixed connection between implants and dental prostheses if proper insertion force is applied. Activation process does not compromise the mechanical functionality of the system. © IMechE 2014.

  12. Experimental study of cone-struts and cavity flameholders in a kerosene-fueled round scramjet combustor

    NASA Astrophysics Data System (ADS)

    Zhang, Dongqing; Song, Wenyan

    2017-10-01

    Experimental investigations of liquid kerosene ignition and flameholding in a round supersonic combustor are presented. Three kinds of flameholders, a cone-struts structure, a cavity and the combination of the both, are studied for the kerosene ignition and flameholding. Results show that ignition and flameholding cannot be achieved by using the sole cone-struts flameholder, although flames are observed at the combustor outlet. The ignition and flameholding are achieved in a narrow range of equivalence ratios by using the cavity flameholder. This range is widened by employing the combination of the cone-struts and the cavity flameholders. It is observed that the back pressure disrupts the isolator entrance flow slightly by using the larger cone-struts (CR = 0.261). However, it does not happen when the smaller cone-struts (CR = 0.221) is employed. Then a characteristic air mass flow rate in the round combustor is redefined to calculate a modified Damkohler number that correlates the nonpremixed flame stability limits. The correlations are in good agreements with the experimental results.

  13. Experimental study of a variable-capacitance micromotor with electrostatic suspension

    NASA Astrophysics Data System (ADS)

    Han, F. T.; Wu, Q. P.; Wang, L.

    2010-11-01

    A variable-capacitance micromotor where the rotor is supported electrostatically in five degrees of freedom was designed, fabricated and tested in order to study the behavior of this electrostatic motor. The micromachined device is based on a glass/silicon/glass stack bonding structure, fabricated by bulk micromachining and initially operated in atmospheric environment. The analytical torque model is obtained by calculating the capacitances between different stator electrodes and the rotor. Capacitance values in the order of 10-13 pF and torque values in the order of 10-10 N m have been calculated from the motor geometry and attainable drive voltage. A dynamic model of the motor is proposed by further estimating the air-film damping effect in an effort to explain the experimental rotation measurements. Experimental results of starting voltage, continuous operation, switching response and electric bearing of the micromotor are presented and discussed. Preliminary measurements indicate that a rotor rotating speed of 73.3 r min-1 can be achieved at a drive voltage of 28.3 V, equivalent to a theoretical motive torque of 517 pN m. Starting voltage results obtained from experimental measurement are in agreement with the developed dynamic model.

  14. Variable Entry Biased Paracentric Hemispherical Deflector: Experimental results on energy resolution for different entry positions

    NASA Astrophysics Data System (ADS)

    Dogan, Mevlut; Ulu, Melike; Gennerakis, Giannis; Zouros, Theo J. M.

    2014-04-01

    A new hemispherical deflector analyzer (HDA) which is designed for electron energy analysis in atomic collisions has been constructed and tested. Using the crossed beam technique at the electron spectrometer, test measurements were performed for electron beam (200 eV) - Helium atoms interactions. These first experimental results show that the paracentric entries give almost twice as good resolution as that for the conventional entry. Supporting simulations of the entire lens+HDA spectrometer are found in relatively good agreement with experiment.

  15. Relative Effectiveness of Two Approaches to the Teaching of Music Theory on the Achievement and Attitudes of Undergraduate Students Training as Church Musicians

    ERIC Educational Resources Information Center

    Kinchen, John Dawson, III

    2012-01-01

    As a result of a perceived need to improve the music theory curricula for the preparation of church music leaders, this study compared two diverse approaches to the teaching of music theory for church music university students on achievement, attitudes, and self-preparedness. This current study was a quantitative, quasi-experimental research…

  16. Heat Transfer Enhancement for Finned-Tube Heat Exchangers with Vortex Generators: Experimental and Numerical Results

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    O'Brien, James Edward; Sohal, Manohar Singh; Huff, George Albert

    2002-08-01

    A combined experimental and numerical investigation is under way to investigate heat transfer enhancement techniques that may be applicable to large-scale air-cooled condensers such as those used in geothermal power applications. The research is focused on whether air-side heat transfer can be improved through the use of finsurface vortex generators (winglets,) while maintaining low heat exchanger pressure drop. A transient heat transfer visualization and measurement technique has been employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements have also been acquired in a separate multiple-tube row apparatus. In addition, numericalmore » modeling techniques have been developed to allow prediction of local and average heat transfer for these low-Reynolds-number flows with and without winglets. Representative experimental and numerical results presented in this paper reveal quantitative details of local fin-surface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. The winglets were triangular (delta) with a 1:2 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface Nusselt-number results indicate a significant level of heat transfer enhancement (average enhancement ratio 35%) associated with the deployment of the winglets with oval tubes. Pressure drop measurements have also been obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that includes four tube rows in a staggered array. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. Heat transfer and pressure-drop results have been obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500.« less

  17. The Effect of Single Gender Instruction on Eighth Grade Students' Mathematics Achievement

    ERIC Educational Resources Information Center

    Hammel, David Michael

    2013-01-01

    In the research study, this investigator utilized a non-experimental, causal-comparative design (ex post facto) with archival data to determine the real impact single gender instruction had on eighth grade students' mathematics achievement. The purpose of this study was to quantitatively analyze the benefits of single gender mathematics…

  18. Cooperative Learning and Learning Achievement in Social Science Subjects for Sociable Students

    ERIC Educational Resources Information Center

    Herpratiwi; Darsono; Sasmiati; Pujiyatli

    2018-01-01

    Purpose: The research objective was to compare students' learning achievement for sociable learning motivation students in social science (IPS) using cooperative learning. Research Methods: This research used a quasi-experimental method with a pre-test/post-test design involving 35 fifth-grade students. The learning process was conducted four…

  19. The Effects of Interactive Video on Cognitive Achievement and Attitude toward Learning.

    ERIC Educational Resources Information Center

    Soled, Suzanne Wegener; And Others

    The purpose of this experimental study was to determine the effects of interactive video versus traditional lecture on cognitive learning and affective behaviors of undergraduate nursing students. It was hypothesized that there would be no significant differences in the cognitive achievement scores of students taught by an interactive videodisk…

  20. Experimental and simulated study of a composite structure metamaterial absorber

    NASA Astrophysics Data System (ADS)

    Li, Shengyong; Ai, Xiaochuan; Wu, Ronghua; Chen, Jiajun

    2017-11-01

    In this paper, a high performance metamaterial absorber is designed and experimental studied. Measured results indicate that a perfect absorption band and a short-wavelength absorption peak are achieved in the near-infrared spectrum. Current strength distributions reveal that the absorption band is excited by the cavity resonance. And electric field distributions show that the short-wavelength absorption peak is excited by the horizontal coupled of localized surface plasmon (LSP) modes near hole edges. On the one hand, the absorption property of the measured metamaterial absorber can be enhanced through optimizing the structural parameters (a, w, and H). On the other hand, the absorption property is sensitive to the change of refractive index of environmental medias. A sensing scheme is proposed for refractive index detecting based on the figure of merit (FOM) value. Measured results indicate that the proposed sensing scheme can achieve high FOM value with different environmental medias (water, glucose solution).