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Sample records for quasi-homogeneous lmfbr concept

  1. Propagation of the light generated by quasi-homogeneous sources through quasi-homogeneous media

    NASA Astrophysics Data System (ADS)

    Li, Jia; Chen, Yan-Ru; Zhao, Qi; Zhou, Mu-Chun; Xu, Shi-Xue

    2010-01-01

    The spectral density of the quasi-homogeneous (QH) light has been known when it scatters on QH media or propagates in free space. The case that QH sources are surrounded by QH media is proposed in this paper. Under the paraxial approximation, the spectral density of the QH light propagating through QH media is derived. A modified scaling law for the propagation of the QH light through QH media is also obtained. This law also holds true in the far field beyond the paraxial approximation.

  2. On the Limit Cycles Bifurcating from Piecewise Quasi-Homogeneous Differential Center

    NASA Astrophysics Data System (ADS)

    Li, Shimin; Wu, Kuilin

    2016-06-01

    In this paper, a class of piecewise smooth quasi-homogeneous differential systems are considered. Using the first order Melnikov function derived in [Liu & Han, 2010], we obtain a lower bound of the maximum number of limit cycles which bifurcate from the periodic annulus of the center under polynomial perturbation. The results reveal that piecewise smooth quasi-homogeneous differential systems can bifurcate more limit cycles than the smooth systems.

  3. Accelerating multi-scale sheet forming simulations by exploiting local macroscopic quasi-homogeneities

    NASA Astrophysics Data System (ADS)

    Gawad, J.; Khairullah, Md; Roose, D.; Van Bael, A.

    2016-08-01

    Multi-scale simulations are computationally expensive if a two-way coupling is employed. In the context of sheet metal forming simulations, a fine-scale representative volume element (RVE) crystal plasticity (CP) model would supply the Finite Element analysis with plastic properties, taking into account the evolution of crystallographic texture and other microstructural features. The main bottleneck is that the fine-scale model must be evaluated at virtually every integration point in the macroscopic FE mesh. We propose to address this issue by exploiting a verifiable assumption that fine-scale state variables of similar RVEs, as well as the derived properties, subjected to similar macroscopic boundary conditions evolve along nearly identical trajectories. Furthermore, the macroscopic field variables primarily responsible for the evolution of fine-scale state variables often feature local quasi-homogeneities. Adjacent integration points in the FE mesh can be then clustered together in the regions where the field responsible for the evolution shows low variance. This way the fine-scale evolution is tracked only at a limited number of material points and the derived plastic properties are propagated to the surrounding integration points subjected to similar deformation. Optimal configurations of the clusters vary in time as the local deformation conditions may change during the forming process, so the clusters must be periodically adapted. We consider two operations on the clusters of integration points: splitting (refinement) and merging (unrefinement). The concept is tested in the Hierarchical Multi-Scale (HMS) framework [1] that computes macroscopic deformations by means of the FEM, whereas the micro-structural evolution at the individual FE integration points is predicted by a CP model. The HMS locally and adaptively approximates homogenized stress responses of the CP model by means of analytical plastic potential or yield criterion function. Our earlier work

  4. Correlation between intensity fluctuations of electromagnetic waves scattered from a spatially quasi-homogeneous, anisotropic medium.

    PubMed

    Li, Jia; Chen, Feinan; Chang, Liping

    2016-10-17

    Within the validity of the first-order Born approximation, expressions are derived for the correlation between intensity fluctuations (CIF) of an electromagnetic plane wave scattered from a spatially quasi-homogeneous (QH), anisotropic medium. Upon establishing the correlation matrix of the scattering potential of the medium, we show that the CIF is the summation of Fourier transforms of the strengths and normalized correlation coefficients (NCCs) of the scattering potential matrix. Numerical results reveal that the CIF is susceptible to the effective width and correlation length of the medium, and degree of polarization of the incident electromagnetic wave. Our study not only extends the current knowledge of the CIF of a scattered field but also provides an important reference to the study of high-order intensity correlations of light scattered from a spatially anisotropic medium.

  5. Acidic ionic liquid as "quasi-homogeneous" catalyst for controllable synthesis of cellulose acetate.

    PubMed

    Tian, Dong; Han, Yangyang; Lu, Canhui; Zhang, Xinxing; Yuan, Guiping

    2014-11-26

    In this paper, we demonstrated that acidic ionic liquids (ILs) can be used as "quasi-homogeneous" catalysts for the efficient acetylation of cellulose. Unlike existing techniques that use large amount of ILs as solvent to dissolve and acetylate cellulose, a small amount of acidic ILs was used as catalyst in this study to overcome the low efficiency associated with relatively high viscosity and costs of ILs during homogeneous acetylation. Fully substituted cellulose acetate with a conversion of 88.8% was obtained by using only 9 mol% IL 1-vinyl-3-(3-sulfopropyl) imidazolium hydrogen sulfate as catalyst, which is much higher than that of common commercialized solid acid catalysts. The degree of substitution and solubility of the obtained cellulose acetate can be facilely controlled by varying the concentration of ILs and reaction time. The dual function of swelling and catalyzing of acidic ILs for the acetylation of cellulose is responsible for the excellent catalytic performance.

  6. Correlation between intensity fluctuations induced by scattering of a partially coherent, electromagnetic wave from a quasi-homogeneous medium

    NASA Astrophysics Data System (ADS)

    Li, Jia; Chang, Liping; Chen, Feinan

    2016-12-01

    Based on the first-order Born approximation, the correlation between intensity fluctuations is derived for a partially coherent, electromagnetic plane wave scattering from a spatially quasi-homogeneous medium. Young's pinholes are utilized to control the degree of coherence of the incident field. For the electromagnetic scattering case, it is shown that the CIF of the scattered field strongly depends on the degree of polarization of the incident wave, Young's pinhole parameter, effective radius and correlation length of the medium. The influences of these parameters on the CIF distributions are revealed by numerical calculations.

  7. Conditions for invariant spectrum of light generated by scattering of partially coherent wave from quasi-homogeneous medium

    NASA Astrophysics Data System (ADS)

    Li, Jia; Wu, Pinghui; Chang, Liping

    2016-02-01

    Within the first-order Born approximation, the spectrum of light generated by the scattering of a partially coherent wave from a quasi-homogeneous (QH) medium is derived. In particular, the partially coherent incident wave is produced by Young's pinholes. It is shown that the spectrum of the scattered field is identical to the spectrum of incident plane waves if the Fourier transform of the normalized correlation coefficient (NCC) of the scattering potential satisfies a certain scaling law. The scaling law is valid when the medium size is sufficiently small compared with the space between Young' pinholes. Furthermore, comparisons are made between our conditions with the previous results.

  8. Simulation of LMFBR

    SciTech Connect

    Agrawal, A.K.

    1982-01-01

    The title of this session is taken to imply the system-wide thermohydraulic simulation of liquid metal fast breeder reactors (LMFBR). One is interested in predicting the temperatures, pressures, and the coolant flow rates throughout the entire plant including the reactor core, the primary and secondary sodium heat transport circuits, the steam generating system as well as other auxiliary circuits. Such a simulation is needed for (1) scoping studies (i.e., in the pre-design phase of a plant), (2) detailed design development, (3) the safety analysis (post-design development phase), and (4) the operator training and plant operation. This session emphasizes the simulation of LMFBRs for only two key categories of transients: operational disturbances or events and the post-shutdown heat removal.

  9. Hockey-stick steam generator for LMFBR

    SciTech Connect

    Hallinan, G.J.; Svedlund, P.E.

    1981-01-01

    This paper presents the criteria and evaluation leading to the selection of the Hockey Stick Steam Generator Concept and subsequent development of that concept for LMFBR application. The selection process and development of the Modular Steam Generator (MSG) is discussed, including the extensive test programs that culminated in the manufacture and test of a 35 MW(t) Steam Generator. The design of the CRBRP Steam Generator is described, emphasizing the current status and a review of the critical structural areas. CRBRP steam generator development tests are evaluated, with a discussion of test objectives and rating of the usefulness of test results to the CRBRP prototype design. Manufacturing experience and status of the CRBRP prototype and plant units is covered. The scaleup of the Hockey Stick concept to large commercial plant application is presented, with an evaluation of scaleup limitations, transient effects, and system design implications.

  10. Effectiveness of the Monte Carlo method in stereotactic radiation therapy applied to quasi-homogenous brain tumors

    PubMed Central

    Kang, Ki Mun; Jeong, Bae Kwon; Choi, Hoon Sik; Song, Jin Ho; Park, Byung-Do; Lim, Young Kyung; Jeong, Hojin

    2016-01-01

    This study was aimed to evaluate the effectiveness of Monte Carlo (MC) method in stereotactic radiotherapy for brain tumor. The difference in doses predicted by the conventional Ray-tracing (Ray) and the advanced MC algorithms was comprehensively investigated through the simulations for phantom and patient data, actual measurement of dose distribution, and the retrospective analysis of 77 brain tumors patients. These investigations consistently showed that the MC algorithm overestimated the dose than the Ray algorithm and the MC overestimation was generally increased as decreasing the beams size and increasing the number of beams delivered. These results demonstrated that the advanced MC algorithm would be inaccurate than the conventional Raytracing algorithm when applied to a (quasi-) homogeneous brain tumors. Thus, caution may be needed to apply the MC method to brain radiosurgery or radiotherapy. PMID:26871473

  11. The ocean quasi-homogeneous layer model and global cycle of carbon dioxide in system of atmosphere-ocean

    NASA Astrophysics Data System (ADS)

    Glushkov, Alexander; Glushkov, Alexander; Loboda, Nataliya; Khokhlov, Valery; Serbov, Nikoly; Svinarenko, Andrey

    The purpose of this paper is carrying out the detailed model of the CO2 global turnover in system of "atmosphere-ocean" with using the ocean quasi-homogeneous layer model. Practically all carried out models are functioning in the average annual regime and accounting for the carbon distribution in bio-sphere in most general form (Glushkov et al, 2003). We construct a modified model for cycle of the carbon dioxide, which allows to reproduce a season dynamics of carbon turnover in ocean with account of zone ocean structure (up quasi-homogeneous layer, thermocline and deepest layer). It is taken into account dependence of the CO2 transfer through the bounder between atmosphere and ocean upon temperature of water and air, wind velocity, buffer mechanism of the CO2 dissolution. The same program is realized for atmosphere part of whole system. It is obtained a tempo-ral and space distribution for concentration of non-organic carbon in ocean, partial press of dissolute CO2 and value of exchange on the border between atmosphere and ocean. It is estimated a role of the wind intermixing of the up ocean layer. The increasing of this effect leads to increasing the plankton mass and further particles, which are transferred by wind, contribute to more quick immersion of microscopic shells and organic material. It is fulfilled investigation of sen-sibility of the master differential equations system solutions from the model parameters. The master differential equa-tions system, describing a dynamics of the CO2 cycle, is numerically integrated by the four order Runge-Cutt method under given initial values of valuables till output of solution on periodic regime. At first it is indicated on possible real-zation of the chaos scenario in system. On our data, the difference of the average annual values for the non-organic car-bon concentration in the up quasi-homogeneous layer between equator and extreme southern zone is 0.15 mol/m3, be-tween the equator and extreme northern zone is 0

  12. Analysis of Pu-Only Partitioning Strategies in LMFBR Fuel Cycles

    SciTech Connect

    Samuel Bays; Gilles Youinou

    2013-02-01

    Sodium cooled Fast Reactors (SFR) have been under consideration for production of electricity, fissile material production, and for destruction of transuranics for decades. The neutron economy of a SFR can be operated in one of two ways. One possibility is to operate the reactor in a transuranic burner mode which has been the focus of active R&D in the last 15 years. However, prior to that the focus was on breeding transuranics. This later mode of managing the neutron economy relies on ensuring the maximum fuel utilization possible in such a way as to maximize the amount of plutonium produced per unit of fission energy in the reactor core. The goal of maximizing plutonium production in this study is as fissile feed stock for the production of MOX fuel to be used in Light Water Reactors (LWR). Throughout the l970’s, this fuel cycle scenario was the focus of much research by the Atomic Energy Commission in the event that uranium supplies would be scarce. To date, there has been sufficient uranium to supply the once through nuclear fuel cycle. However, interest in a synergistic relationship Liquid Metal Fast Breeder Reactors (LMFBR) and a consumer LWR fleet persists, prompting this study. This study considered LMFBR concepts with varying additions of axial and radial reflectors. Three scenarios were considered in collaboration with a companion study on the LWR-MOX designs based on plutonium nuclide vectors produced by this study. The first scenario is a LMFBR providing fissile material to make MOX fuel where the MOX part of the fuel cycle is operated in a once-through-then-out mode. The second scenario is the same as the first but with the MOX part of the fuel cycle multi-recycling its own plutonium with LMFBR being used for the make-up feed. In these first two scenarios, plutonium partitioning from the minor actinides (MA) was assumed. Also, the plutonium management strategy of the LMFBR ensured that only the high fissile purity plutonium bred from blankets was

  13. Correlation between intensity fluctuations of light generated by scattering of Young’s diffractive electromagnetic waves by a quasi-homogeneous, anisotropic medium

    NASA Astrophysics Data System (ADS)

    Li, Jia; Chen, Feinan

    2016-11-01

    Based on the first-order Born approximation, formulas are derived for the correlation between intensity fluctuations (CIF) of light generated by a Young’s diffractive electromagnetic wave scattered by a spatially quasi-homogeneous (QH), anisotropic medium. It is shown that the CIF of the scattered field can be written as the summation of the Fourier transforms of the strengths and normalized correlation coefficients (NCCs) of the scattering potentials. The differences between our results and those obtained in the previous literature are discussed. Our results might be important in investigating the high-order intensity correlation of an electromagnetic wave scattered from a 3D anisotropic object.

  14. On validating Quasi-Steady Quasi-Homogeneous nature of the relationgship between large-scale and small-scale structures in a turbulent boundary layer

    NASA Astrophysics Data System (ADS)

    Zhang, Chi; Chernyshenko, Sergei

    2016-11-01

    A formal definition to the two hypotheses of the quasi-steady and quasi-homogeneous (QSQH) theory was proposed. The theory is supposed to explain the phenomenon of the large-scale structures influencing the small-scale structures in a turbulent boundary layer. Multi-objective optimisations were performed to find the optimal cut-off parameters for the new large-scale filters. The new filters were proved to obtain much more clear large-scale structures than the filter suggested by the previous studies. Calculations and comparisons for a set of statistical flow properties extracted from the databases of the direct numerical simulations of a plane channel flow were conducted. The accuracy of the predictions based on the QSQH theory was observed improving when the Reynolds number increases. Extrapolations of urms and two-points correlation from medium to high Reynolds number based on the QSQH approach were preformed and about 10 % accuracy was reported. The more interesting thing is that the QSQH theory implies a dependence of the mean profile log-law constants on the Reynolds number. The main overall result of the present work is the validations of the two hypotheses of the quasi-steady quasi-homogeneous theory in near-wall turbulent flows.

  15. LMFBR with booster pump in pumping loop

    DOEpatents

    Rubinstein, H.J.

    1975-10-14

    A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation.

  16. Coolant mixing in LMFBR rod bundles and outlet plenum mixing transients. Progress report

    SciTech Connect

    Todreas, N.E.; Golay, M.W.; Wold, L.

    1981-02-01

    Four tasks are reported on: bundle geometry (wrapped and bare rods), subchannel geometry (bare rods), LMFBR outlet plenum flow mixing, and theoretical determination of local temperature fields in LMFBR fuel rod bundles. (DLC)

  17. LOA-1: prevent accidents. Quarterly technical progress report, FRSP program - July through September 1981. [LMFBR

    SciTech Connect

    Not Available

    1981-01-01

    Information related to LMFBR reactor safety is presented concerning common cause failures; shutdown by self-activated system; shutdown heat removal system operation; sodium burning; core catcher material interactions; accident release of sodium oxide aerosol; and LMFBR risk assessment.

  18. Fuels and materials for LMFBR core components

    SciTech Connect

    Cox, C M; Jackson, R J; Straalsund, J L

    1984-04-01

    This paper reviews development of fuels and materials for Liquid Metal Fast Breeder Reactor. Included are the status of fuels and materials technology for LMFBR core components. The fuel assembly for the Fast Flux Test Facility, or FFTF, in operation near Richland, Washington, is described. The outer part of the 12-ft long assembly is called a flow channel or duct. Inside are 217 fuel pins, each containing mixed uranium-plutonium oxide fuel pellets. The comparable schematic for control rod or absorber assembly is also shown. The FFTF absorber assembly contains 61 control rods containing boron carbide pellets. Because FFTF is a test reactor, it does not contain blanket assemblies; however, the Clinch River Breeder Reactor blanket assemblies look very similar to the FFTF fuel assembly, except that they each contain 61 UO/sub 2/ rods. Sizes of various LMFBR fuel assemblies are compared. The Clinch River Breeder Reactor fuel assembly is nearly identical to that of FFTF, except for an increased length to accommodate UO/sub 2/ axial blankets within the fuel pins. The DP-1 design is for a large breeder reactor and uses larger ducts and more fuel pins per assembly. By comparison, the fuel assemblies for EBR-II are much smaller, as is the EBR-II core.

  19. Gravitational agglomeration of post-HCDA LMFBR nonspherical aerosols

    NASA Astrophysics Data System (ADS)

    Tuttle, R. F.

    1980-12-01

    A theoretical investigation of collisional dynamics of two particle interactions in a gravitational field is reported. This research is unique in that it is the first attempt at modeling the hydrodynamic interactions between a nonspherical particle and a spherical particle undergoing gravitational collisions in an LMFBR environment. Basic definitions and expressions are developed for nonspherical particles and related to spherical particles by means of shape factors. Using volume equivalent diameter as the defining length in the gravitational collision kernel, the aerodynamic shape factor, k, the density correction factor, alpha, and the gravitational collision shape factor, beta, are used to correct the collision kernel for the case of collisions between aerosol agglomerates. The Navier-Stokes equation in oblate spheroidal coordinates is solved to model a nonspherical particle and then the dynamic equations for two particle motions are developed. A computer program NGCEFF is constructed, the Navier-Stokes equation is solved by the finite difference method, and the dynamical equations are solved by Gear's method. It is concluded that the aerosol gravitational collision shape factor can be determined by further theoretical work based on the concepts and methods developed in this dissertation.

  20. Reactor control rod timing system. [LMFBR

    DOEpatents

    Wu, P.T.K.

    1980-03-18

    A fluid driven jet-edge whistle timing system is described for control rods of a nuclear reactor for producing real-time detection of the timing of each control rod in its scram operation. An important parameter in reactor safety, particularly for liquid metal fast breeder reactors (LMFBR), is the time deviation between the time the control rod is released and the time the rod actually reaches the down position. The whistle has a nearly pure tone signal with center frequency (above 100 kHz) far above the frequency band in which the energy of the background noise is concentrated. Each control rod can be fitted with a whistle with a different frequency so that there is no ambiguity in differentiating the signal from each control rod.

  1. MO-F-CAMPUS-I-02: Accuracy in Converting the Average Breast Dose Into the Mean Glandular Dose (MGD) Using the F-Factor in Cone Beam Breast CT- a Monte Carlo Study Using Homogeneous and Quasi-Homogeneous Phantoms

    SciTech Connect

    Lai, C; Zhong, Y; Wang, T; Shaw, C

    2015-06-15

    Purpose: To investigate the accuracy in estimating the mean glandular dose (MGD) for homogeneous breast phantoms by converting from the average breast dose using the F-factor in cone beam breast CT. Methods: EGSnrc-based Monte Carlo codes were used to estimate the MGDs. 13-cm in diameter, 10-cm high hemi-ellipsoids were used to simulate pendant-geometry breasts. Two different types of hemi-ellipsoidal models were employed: voxels in quasi-homogeneous phantoms were designed as either adipose or glandular tissue while voxels in homogeneous phantoms were designed as the mixture of adipose and glandular tissues. Breast compositions of 25% and 50% volume glandular fractions (VGFs), defined as the ratio of glandular tissue voxels to entire breast voxels in the quasi-homogeneous phantoms, were studied. These VGFs were converted into glandular fractions by weight and used to construct the corresponding homogeneous phantoms. 80 kVp x-rays with a mean energy of 47 keV was used in the simulation. A total of 109 photons were used to image the phantoms and the energies deposited in the phantom voxels were tallied. Breast doses in homogeneous phantoms were averaged over all voxels and then used to calculate the MGDs using the F-factors evaluated at the mean energy of the x-rays. The MGDs for quasi-homogeneous phantoms were computed directly by averaging the doses over all glandular tissue voxels. The MGDs estimated for the two types of phantoms were normalized to the free-in-air dose at the iso-center and compared. Results: The normalized MGDs were 0.756 and 0.732 mGy/mGy for the 25% and 50% VGF homogeneous breasts and 0.761 and 0.733 mGy/mGy for the corresponding quasi-homogeneous breasts, respectively. The MGDs estimated for the two types of phantoms were similar within 1% in this study. Conclusion: MGDs for homogeneous breast models may be adequately estimated by converting from the average breast dose using the F-factor.

  2. Comments on US LMFBR steam generator base technology

    SciTech Connect

    Simmons, W.R.

    1984-01-01

    The development of steam generators for the LMFBR was recognized from the onset by the AEC, now DOE, as a difficult, challenging, and high-priority task. The highly reactive nature of sodium with water/steam requires that the sodium-water/steam boundaries of LMFBR steam generators possess a degree of leak-tightness reliability not normally attempted on a commercial scale. In addition, the LMFBR steam generator is subjected to high fluid temperatures and severe thermal transients. These requirements place great demand on materials, fabrication processes, and inspection methods; and even greater demands on the designer to provide steam generators that can meet these demanding requirements, be fabricated without unreasonable shop requirements, and tolerate off-normal effects.

  3. Gravitational Agglomeration of Post-HCDA LMFBR Nonspherical Aerosols.

    DTIC Science & Technology

    1980-12-01

    AD-AIO6 766 AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH F/B 13/7 GRAVITATIONAL AGGLOMERATION OF POST- HCDA LMF8R NONSPHFRICAL AER--ETC(U) DEC 80 R...OF REPORT & PERIOD COVERED i Gravitational Agglomeration of Post- HCDA TfIfM/DISSERTATION LMFBR Nonspherical Aerosols . ________O____O______________ S...it to: AFIT/NR Wright-Patterson AFB OH 45433 RESEARCH TITLE: Gravitational Agglomeration of Post- HCDA LMFBR Nonspherical Aerosols AUTHOR: Ronald

  4. Coolant mixing in LMFBR rod bundles and outlet plenum mixing transients. Progress report, March 1, 1980-May 31, 1980

    SciTech Connect

    Todreas, N.E.; Golay, M.W.; Wolf, L.

    1980-01-01

    Experimental and theoretical work is reported on four tasks: bundle geometry (wrapped and bare rods), subchannel geometry (bare rods), LMFBR outlet plenum flow mixing, and theoretical local temperature files in LMFBR fuel rod bundles. (DLC)

  5. Coolant mixing in LMFBR rod bundles and outlet plenum mixing transients. Progress report, September 1, 1980-November 30, 1980

    SciTech Connect

    Todreas, N.E.; Golay, M.W.; Wolf, L.

    1981-02-01

    Four tasks are reported: bundle geometry (wrapped and bare rods), subchannel geometry (bare rods), subchannel geometry (bare rods), LMFBR outlet plenum flow mixing, and theoretical determination of local temperature fields in LMFBR fuel rod bundles. (DLC)

  6. Model for LMFBR core transient analysis in real-time

    SciTech Connect

    Tzanos, C.P.

    1986-01-01

    This paper discusses the modeling of LMFBR core transients. It is shown that with a proper choice of shape functions a nodal approximation of the coolant, cladding, and fuel temperature distributions leads to adequately accurate power and temperature predictions, as well as adequately short computation times.

  7. An analytical tool for PIN contact incident of LMFBR fuel-subassembly

    SciTech Connect

    Miyakoshi, Hiroyuki; Haga, Kazuo

    1997-12-01

    A subchannel computer code COBRA-41 was modified for LMFBR local faults analysis. Calculational results to a pin contact condition were compared with experimental ones and trial calculations were made to an LMFBR fuel-subassembly geometry. 8 refs., 8 figs., 2 tabs.

  8. Bundle duct interaction studies for fuel assemblies. [LMFBR

    SciTech Connect

    Hsia, H.T.S.; Kaplan, S.

    1981-06-01

    It is known that the wire-wrapped rods and duct in an LMFBR are undergoing a gradual structural distortion from the initially uniform geometry under the combined effects of thermal expansion and irradiation induced swelling and creep. These deformations have a significant effect on flow characteristics, thus causing changes in thermal behavior such as cladding temperature and temperature distribution within a bundle. The temperature distribution may further enhance or retard irradiation induced deformation of the bundle. This report summarizes the results of the continuing effort in investigating the bundle-duct interaction, focusing on the need for the large development plant.

  9. Performance of breached LMFBR fuel pins during continued operation

    SciTech Connect

    Lambert, J.D.B.; Strain, R.V.; Gross, K.C.; Hofman, G.L.; Colburn, R.P.; Adamson, M.G.; Ukai, S.

    1985-01-01

    Four EBR-II tests were used to scope the behavior of breached mixed-oxide pins. After release of stored fission gas, delayed-neutron signals were large and easily detected, although not readily correlated with exposed fuel area. No problems were met during reactor operation or fuel handling. Fuel-sodium reaction caused only narrow breaches which released minute amounts of fuel and fission products; the reaction product appeared dense and non-friable. These initial results indicated LMFBR oxide pins could have considerable potential for operating in the breached mode.

  10. LMFBR models for the ORIGEN2 computer code

    SciTech Connect

    Croff, A.G.; McAdoo, J.W.; Bjerke, M.A.

    1981-10-01

    Reactor physics calculations have led to the development of nine liquid-metal fast breeder reactor (LMFBR) models for the ORIGEN2 computer code. Four of the models are based on the U-Pu fuel cycle, two are based on the Th-U-Pu fuel cycle, and three are based on the Th-/sup 238/U fuel cycle. The reactor models are based on cross sections taken directly from the reactor physics codes. Descriptions of the reactor models as well as values for the ORIGEN2 flux parameters THERM, RES, and FAST are given.

  11. LMFBR models for the ORIGEN2 computer code

    SciTech Connect

    Croff, A.G.; McAdoo, J.W.; Bjerke, M.A.

    1983-06-01

    Reactor physics calculations have led to the development of nine liquid-metal fast breeder reactor (LMFBR) models for the ORIGEN2 computer code. Four of the models are based on the U-Pu fuel cycle, two are based on the Th-U-Pu fuel cycle, and three are based on the Th-/sup 233/U fuel cycle. The reactor models are based on cross sections taken directly from the reactor physics codes. Descriptions of the reactor models as well as values for the ORIGEN2 flux parameters THERM, RES, and FAST are given.

  12. Blow-down tests in a sodium-heated steam generator tube. [LMFBR

    SciTech Connect

    France, D.M.; Carlson, R.D.; Chiang, T.

    1983-01-01

    The design of steam generators for liquid metal fast breeder reactor (LMFBR) electric power plants is based on both normal load operation and plant transient conditions. Perhaps the most severe transient to which an LMFBR steam generator may be subjected is known as the water-side isolation and dump transient, often called the blow-down transient. LMFBR steam generators must be designed to accommodate a small but finite number of the blow-down transients. The purpose of this investigation was to perform a blow-down experiment in a well instrumented, full scale, single tube model of an LMFBR steam generator. The data may be used directly in steam generator design and as a validation point for steam generator mathematical models in plant transient computer codes.

  13. Reactor safety. Annual technical progress report, Government fiscal year 1979. [LMFBR

    SciTech Connect

    Not Available

    1980-04-15

    Information is presented on LMFBR reactor safety concerning the energetics effects of sodium spray fires; sodium drop and spray burning; core debris accommodation; attenuation in containment; and attenuation in the environment.

  14. Investigation of the physical and numerical foundations of two-fluid representation of sodium boiling with applications to LMFBR experiments

    SciTech Connect

    No, H.C.; Kazimi, M.S.

    1983-03-01

    This work involves the development of physical models for the constitutive relations of a two-fluid, three-dimensional sodium boiling code, THERMIT-6S. The code is equipped with a fluid conduction model, a fuel pin model, and a subassembly wall model suitable for stimulating LMFBR transient events. Mathematically rigorous derivations of time-volume averaged conservation equations are used to establish the differential equations of THERMIT-6S. These equations are then discretized in a manner identical to the original THERMIT code. A virtual mass term is incorporated in THERMIT-6S to solve the ill-posed problem. Based on a simplified flow regime, namely cocurrent annular flow, constitutive relations for two-phase flow of sodium are derived. The wall heat transfer coefficient is based on momentum-heat transfer analogy and a logarithmic law for liquid film velocity distribution. A broad literature review is given for two-phase friction factors. It is concluded that entrainment can account for some of the discrepancies in the literature. Mass and energy exchanges are modelled by generalization of the turbulent flux concept. Interfacial drag coefficients are derived for annular flows with entrainment. Code assessment is performed by simulating three experiments for low flow-high power accidents and one experiment for low flow/low power accidents in the LMFBR. While the numerical results for pre-dryout are in good agreement with the data, those for post-dryout reveal the need for improvement of the physical models. The benefits of two-dimensional non-equilibrium representation of sodium boiling are studied.

  15. MIT LMFBR blanket research project. Final summary report

    SciTech Connect

    Driscoll, M.J.

    1983-08-01

    This is a final summary report on an experimental and analytical program for the investigation of LMFBR blanket characteristics carried out at MIT in the period 1969 to 1983. During this span of time, work was carried out on a wide range of subtasks, ranging from neutronic and photonic measurements in mockups of blankets using the Blanket Test Facility at the MIT Research Reactor, to analytic/numerical investigations of blanket design and economics. The main function of this report is to serve as a resource document which will permit ready reference to the more detailed topical reports and theses issued over the years on the various aspects of project activities. In addition, one aspect of work completed during the final year of the project, on doubly-heterogeneous blanket configurations, is documented for the record.

  16. Overview of the fast reactors fuels program. [LMFBR

    SciTech Connect

    Evans, E.A.; Cox, C.M.; Hayward, B.R.; Rice, L.H.; Yoshikawa, H.H.

    1980-04-01

    Each nation involved in LMFBR development has its unique energy strategies which consider energy growth projections, uranium resources, capital costs, and plant operational requirements. Common to all of these strategies is a history of fast reactor experience which dates back to the days of the Manhatten Project and includes the CLEMENTINE Reactor, which generated a few watts, LAMPRE, EBR-I, EBR-II, FERMI, SEFOR, FFTF, BR-1, -2, -5, -10, BOR-60, BN-350, BN-600, JOYO, RAPSODIE, Phenix, KNK-II, DFR, and PFR. Fast reactors under design or construction include PEC, CRBR, SuperPhenix, SNR-300, MONJU, and Madras (India). The parallel fuels and materials evolution has fully supported this reactor development. It has involved cermets, molten plutonium alloy, plutonium oxide, uranium metal or alloy, uranium oxide, and mixed uranium-plutonium oxides and carbides.

  17. CAT reconstruction and potting comparison of a LMFBR fuel bundle

    SciTech Connect

    Betten, P.R.; Tow, D.M.

    1984-04-01

    A standard Liquid Metal Fast Breeder Reactor (LMFBR) subassembly used in the Experimental Breeder Reactor II (EBR-II) was investigated, by remote techniques, for fuel bundle distortion by both nondestructive and destructive methods, and the results from both methods were compared. The non-destructive method employed neutron tomography to reconstruct the locations of fuel elements through the use of a maximum entropy reconstruction algorithm known as MENT. The destructive method consisted of ''potting'' (a technique that embeds and permanently fixes the fuel elements in a solid matrix) the subassembly, and then cutting and polishing the individual sections. The comparison indicated that the tomography reconstruction provided good results in describing the bundle geometry and spacer-wire locations, with the overall resolution being on the order of a spacer-wire diameter. A dimensional consistency check indicated that the element and spacer-wire dimensions were accurately reproduced in the reconstruction.

  18. Operational-safety advantages of LMFBR's: the EBR-II experience and testing program

    SciTech Connect

    Sackett, J.I.; Lindsay, R.W.; Golden, G.H.

    1982-01-01

    LMFBR's contain many inherent characteristics that simplify control and improve operating safety and reliability. The EBR-II design is such that good advantage was taken of these characteristics, resulting in a vary favorable operating history and allowing for a program of off-normal testing to further demonstrate the safe response of LMFBR's to upsets. The experience already gained, and that expected from the future testing program, will contribute to further development of design and safety criteria for LMFBR's. Inherently safe characteristics are emphasized and include natural convective flow for decay heat removal, minimal need for emergency power and a large negative reactivity feedback coefficient. These characteristics at EBR-II allow for ready application of computer diagnosis and control to demonstrate their effectiveness in response to simulated plant accidents. This latter testing objective is an important part in improvements in the man-machine interface. (MMI)

  19. Analysis of potential attack on insulating materials exposed to sodium. Final report. [LMFBR

    SciTech Connect

    Allam, I.M.; Lamoreaux, R.H.; Loehman, R.E.

    1981-08-01

    The use of ceramics for thermally insulating the header of the LMFBR (liquid metal fast breeder reactor) is primarily determined by the chemical compatibility of the ceramics and liquid sodium. A series of thermodynamic calculations of ceramic stabilities as a function of oxygen concentration in the liquid sodium was used to select materials for experimental testing. Several commercial ceramics were exposed to liquid sodium for 10 weeks at 741/sup 0/K, in a test program aimed at evaluating their suitability as LMFBR insulators.

  20. Multirecycling of Plutonium from LMFBR Blanket in Standard PWRs Loaded with MOX Fuel

    SciTech Connect

    Sonat Sen; Gilles Youinou

    2013-02-01

    It is now well-known that, from a physics standpoint, Pu, or even TRU (i.e. Pu+M.A.), originating from LEU fuel irradiated in PWRs can be multirecycled also in PWRs using MOX fuel. However, the degradation of the isotopic composition during irradiation necessitates using enriched U in conjunction with the MOX fuel either homogeneously or heterogeneously to maintain the Pu (or TRU) content at a level allowing safe operation of the reactor, i.e. below about 10%. The study is related to another possible utilization of the excess Pu produced in the blanket of a LMFBR, namely in a PWR(MOX). In this case the more Pu is bred in the LMFBR, the more PWR(MOX) it can sustain. The important difference between the Pu coming from the blanket of a LMFBR and that coming from a PWR(LEU) is its isotopic composition. The first one contains about 95% of fissile isotopes whereas the second one contains only about 65% of fissile isotopes. As it will be shown later, this difference allows the PWR fed by Pu from the LMFBR blanket to operate with natural U instead of enriched U when it is fed by Pu from PWR(LEU)

  1. Final report of the APRICOT Program and results of Phase 3. [LMFBR

    SciTech Connect

    Not Available

    1982-09-01

    APRICOT (Analysis of PRImary COntainment Transients) was a cooperative activity for comparison and benchmarking of computational methods used to analyze LMFBR (Liquid Metal Fast Breeder Reactor) structural response to pressure loads from HCDA's (Hypothetical Core Disruptive Accidents). The participants were LMFBR project groups from Europe, Japan and the United States. Independent experts reviewed the calculations for the purpose of comparing computational results and methods of solution. Phase 3 involved a series of simple calculations of structural response and fluid-structure interactions under elastic and elastic-plastic conditions. The results were generally in reasonable agreement although there were a few anomalies. The APRICOT program has provided significant code validation data to enhance confidence in numerical simulations of HCDA's. It has also demonstrated the value of this type of benchmark activity.

  2. Contribution of Clinch River Breeder Reactor plant design and development to the LMFBR fuel cycle

    SciTech Connect

    Riley, D.R.; Dickson, P.W.

    1981-01-01

    This paper describes how the CRBRP development and CRBRP focus of the LMFBR base technology program have led to advances in the state of the art in physics, thermal-hydraulics, structural analysis, core restraint, seismic analysis, and analysis of hypothetical core-disruptive accident energetics, all of which have been incorporated through disciplined engineering into the final CRBRP design. The total development in the US of fuels and materials, the analytical advances made on CRBRP design, and the incorporation of the latest experimental results into that design have put the US technology in general and the CRBRP design in particular at the forefront of technology. This has placed the US in a position to develop the most favorable LMFBR fuel cycle.

  3. LMFBR conceptual design study: an overview of environmental and safety concerns

    SciTech Connect

    Brenchley, D.L.

    1981-06-01

    The US Department of Energy (DOE) initiated the Liquid Metal Fast Breeder (LMFBR) Conceptual Design Study (CDS) with the objective of maintaining a viable breeder option. The project is scheduled to be completed in FY-1981 but decisions regarding plant construction will be delayed until at least 1985. This report provides a review of the potential environmental and safety engineering concerns for the CDS and recommends specific action for the Environmental and Safety Engineering Division of DOE.

  4. LMFBR system-wide transient analysis: the state of the art and US validation needs

    SciTech Connect

    Khatib-Rahbar, M.; Guppy, J.G.; Cerbone, R.J.

    1982-01-01

    This paper summarizes the computational capabilities in the area of liquid metal fast breeder reactor (LMFBR) system-wide transient analysis in the United States, identifies various numerical and physical approximations, the degree of empiricism, range of applicability, model verification and experimental needs for a wide class of protected transients, in particular, natural circulation shutdown heat removal for both loop- and pool-type plants.

  5. SUPERENERGY-2: a multiassembly, steady-state computer code for LMFBR core thermal-hydraulic analysis

    SciTech Connect

    Basehore, K.L.; Todreas, N.E.

    1980-08-01

    Core thermal-hydraulic design and performance analyses for Liquid Metal Fast Breeder Reactors (LMFBRs) require repeated detailed multiassembly calculations to determine radial temperature profiles and subchannel outlet temperatures for various core configurations and subassembly structural analyses. At steady-state, detailed core-wide temperature profiles are required for core restraint calculations and subassembly structural analysis. In addition, sodium outlet temperatures are routinely needed for each reactor operating cycle. The SUPERENERGY-2 thermal-hydraulic code was designed specifically to meet these designer needs. It is applicable only to steady-state, forced-convection flow in LMFBR core geometries.

  6. 85,000-GPM, single-stage, single-suction LMFBR intermediate centrifugal pump

    SciTech Connect

    Fair, C.E.; Cook, M.E. Huber, K.A.; Rohde, R.

    1983-01-01

    The mechanical and hydraulic design features of the 85,000-gpm, single-stage, single-suction pump test article, which is designed to circulate liquid-sodium coolant in the intermediate heat-transport system of a Large-Scale Liquid Metal Fast Breeder Reactor (LS-LMFBR), are described. The design and analytical considerations used to satisfy the pump performance and operability requirements are presented. The validation of pump hydraulic performance using a hydraulic scale-model pump is discussed, as is the featute test for the mechanical-shaft seal system.

  7. Modeling considerations for the analysis of LMFBR steam generator tube clamps

    SciTech Connect

    Lay, D.M.; Piper, R.M.

    1982-01-01

    In the design of the Babcock and Wilcox Helical Coil Liquid Metal Fast Breeder Reactor (LMFBR) Steam Generator, the tube bundle is connected to the feedwater and steam plenums via ''inlet/outlet tubes''. Of prime importance in the design of these tubes is the tube-to-tube and tube-to-shell clamps which are provided to prevent detrimental vibration. This paper presents a method of modeling the tube-to-tube clamps to accurately predict tube-to-clamp interaction in the finite element analysis. It also demonstrates the validity of specific modeling assumptions in determining stresses in the clamp assembly.

  8. Evaluation of molten lead mixing in sodium coolant by diffusion for application to PAHR. [LMFBR

    SciTech Connect

    Chawla, T.C.; Pedersen, D.R.; Leaf, G.; Minkowycz, W.J.

    1983-01-01

    In post-accident heat removal (PAHR) applications the use of a lead slab is being considered for protecting a porous bed of steel shots in ex-vessel cavity from direct impingement of molten steel or fuel upon vessel failure following a hypothetical core dissembly accident in an LMFBR. The porous bed is provided to increase coolability of the fuel debris by the sodium coolant. The objectives of the present study are (1) to determine melting rates of lead slabs of various thicknesses in contact with sodium coolant and (2) to evaluate the extent of penetration and mixing rates of molten lead into sodium coolant by molecular diffusion alone.

  9. Compressible analysis of inlet plenum pressure rise due to sodium boiling in fuel subassemblies during pump coastdown of an LMFBR

    SciTech Connect

    Kalimullah; Hummel, H.H.

    1980-05-01

    The effect of sodium compressibility and steel elasticity on the rise in inlet plenum pressure occurring during boiling in a loss-of-flow accident in an LMFBR has been investigated using the require consideration in accident analysis. The pressure rise is less for pool than for loop designs. 3 refs., 1 fig., 9 tabs.

  10. A study on reactor core failure thresholds to safety operation of LMFBR

    SciTech Connect

    Kazuo, Haga; Hiroshi, Endo; Tomoko, Ishizu; Yoshihisa, Shindo

    2006-07-01

    Japan Nuclear Safety Organization (JNES) has been developing the methodology and computer codes for applying level-1 PSA to LMFBR. Many of our efforts have been directed to the judging conditions of reactor core damage and the time allowed to initiate the accident management. Several candidates of the reactor core failure threshold were examined to a typical proto-type LMFBR with MOX fuel based on the plant thermal-hydraulic analyses to the actual progressions leading to the core damage. The results of the present study showed that the judging condition of coolant-boundary integrity failure, 750 degree-C of the boundary temperature, is enough as the threshold of core damage to PLOHS (protected loss-of-heat sink). High-temperature fuel cladding creep failure will not take place before the coolant-boundary reaches the judging temperature and sodium boiling will not occur due to the system pressure rise. In cases of ATWS (anticipated transient without scrum) the accident progression is so fast and the reactor core damage will be inevitable even a realistic negative reactivity insertion due to the temperature rise is considered. Only in the case of ULOHS (unprotected loss-of-heat sink) a relatively long time of 11 min will be allowed till the shut-down of the reactor before the core damage. (authors)

  11. Hardware concepts for a large low-energetics LMFBR core. Final report

    SciTech Connect

    Hutter, E.; Batch, R.V.

    1980-12-01

    A design study was made to identify a practical set of hardware configurations that would embody the requirements developed in the numerical study of a low-energetics core and blanket for a prototype large breeder reactor. Dimensioned drawings are presented for fuel, blanket, reflector/shield, and control rod subassemblies. A horizontal cross section drawing shows how these subassemblies are arranged in the total core/blanket assembly. A core support is illustrated showing a dual plenums arrangement.

  12. LMFBR in-core thermal-hydraulics: the state of the art and US research and development needs

    SciTech Connect

    Khan, E.U.

    1980-04-01

    A detailed critical review is presented of the literature relevant to predicting coolant flow and temperature fields in LMFBR core assemblies for nominal and non-nominal rod bundle geometries and reactor operating conditions. The review covers existing thermal-hydraulic models, computational methods, and experimental data useful for the design of an LMFBR core. The literature search made for this review included publications listed by Nuclear Science Abstracts and Energy Data Base as well as papers presented at key nuclear conferences. Based on this extensive review, the report discusses the accuracy with which the models predict flow and temperature fields in rod assemblies, identifying areas where analytical, experimental, and model development needs exist.

  13. Analysis of loss-of-flow transients in a pool-type LMFBR using SSC-P

    SciTech Connect

    Madni, I.K.; Cazzoli, E.G.

    1982-01-01

    In order to have a general analytical capability for the safety evaluation of any proposed LMFBR system, the USNRC is sponsoring the development and validation of computer codes for both pool- and loop-type plants. The computer code for pool-type LMFBRs is designated SSC-P. This paper is concerned with the application of SSC-P to simulate loss-of-flow accident transients in a pool-type LMFBR. The models required for dynamic plant simulation are briefly highlighted. The system response is calculated for (1) a complete loss of electric power event, with scram, leading the plant into buoyancy-induced natural circulation, (2) a protected pipe rupture accident in the primary pump discharge line, and (3) an unprotected loss of off-site power event. For the last case, the predicted results from SSC-P are compared with the published results of Phenix behavior by NOVATOME.

  14. Development of a methodology for analysis of delayed-neutron signals. [LMFBR

    SciTech Connect

    Gross, K. C.; Strain, R. V.; Fryer, R. M.

    1980-02-01

    Experimental and analytical techniques have been developed for analysis and characterization of delayed-neutron (DN) signals that can provide diagnostic information to augment data from cover-gas analyses in the detection and identification of breached elements in an LMFBR. Eleven flow-reduction tests have been run in EBR-II to provide base data support for predicting DN signal characteristics during exposed-fuel operation. Results from the tests demonstrate the feasibility and practicability of response-analysis techniques for determining (a) the transit time, T/sub tr/, for DN emitters traveling from the core to the detector and (b) the isotropic holdup time, T/sub h/, of DN precursors in the fuel element.

  15. Results of phase 2 of the APRICOT program. Final report. [LMFBR

    SciTech Connect

    Not Available

    1981-05-01

    APRICOT (Analysis of Primary Containment Transients) is a cooperative activity for comparison and benchmarking of computational methods used to analyze LMFBR (Liquid Metal Fast Breeder Reactor) structural response to pressure loads from HCDA's (Hypothetical Core Disruptive Accidents). Independent experts review the calculations for the purpose of comparing computational results and methods of solution. Phase 2 involved a series of more complex calculations based on the simulation of scaled-down containment experiments. These calculations, as those of Phase 1, were performed by participants from Europe, Japan and the United States. The calculations were all in reasonable agreement with experimental determinations of hydrodynamic loads; however, the calculated plastic strains differed significantly from the experimental results. The unresolved issues from the Phase 2 calculations are currently being studied with the calculations for Phase 3.

  16. Modeling considerations for the analysis of LMFBR steam generator tube clamps

    SciTech Connect

    Lay, D.M.; Piper, R.M.

    1983-10-01

    In the design of the Babcock and Wilcox Helical Coil Liquid Metal Fast Breeder Reactor (LMFBR) Steam Generator, the tube bundle is connected to the feedwater and steam plenums via ''inlet/outlet tubes.'' Of prime importance in the design of these tubes is the tube-to-tube and tube-to-shell clamps which are provided to prevent detrimental vibration. This paper presents a method of modeling the tubeto-tube clamps to accurately predict tube-to-clamp interaction in the finite element analysis. It is also the objective of this paper to demonstrate the validity of specific modeling assumptions in determining stresses in the clamp assembly. As this paper deals only with the analytical approach taken, no detailed results are presented.

  17. Coolant mixing in LMFBR rod bundles and outlet plenum mixing transients. Final report

    SciTech Connect

    Todreas, N.E.; Cheng, S.K.; Basehore, K.

    1984-08-01

    This project principally undertook the investigation of the thermal hydraulic performance of wire wrapped fuel bundles of LMFBR configuration. Results obtained included phenomenological models for friction factors, flow split and mixing characteristics; correlations for predicting these characteristics suitable for insertion in design codes; numerical codes for analyzing bundle behavior both of the lumped subchannel and distributed parameter categories and experimental techniques for pressure velocity, flow split, salt conductivity and temperature measurement in water cooled mockups of bundles and subchannels. Flow regimes investigated included laminar, transition and turbulent flow under forced convection and mixed convection conditions. Forced convections conditions were emphasized. Continuing efforts are underway at MIT to complete the investigation of the mixed convection regime initiated here. A number of investigations on outlet plenum behavior were also made. The reports of these investigations are identified.

  18. Analysis of three idealized reactor configurations: plate, pin, and homogeneous. [LMFBR

    SciTech Connect

    McKnight, R.D.

    1983-01-01

    Detailed Monte Carlo calculations have been performed for three distinct configurations of an idealized fast critical assembly. This idealized assembly was based on the LMFBR benchmark critical assembly ZPR-6/7. In the first configuration, the entire core was loaded with the plate unit cell of ZPR-6/7. In the second configuration, the entire core was loaded with the ZPR sodium-filled pin calandria. The actual ZPR pin calandria are loaded with mixed (U,Pu) oxide pins which closely match the composition of the ZPR-6/7 plate unit cell. For the present study, slight adjustments were made in the atom concentrations and the length of the pin calandria in order to make the core boundaries and average composition for the pin-cell configuration identical to those of the plate-cell configuration. In the third configuration, the core was homogeneous, again with identical core boundaries and average composition as the plate and pin configurations.

  19. DYNAPCON: a computer code for dynamic analysis of prestressed concrete structures. [LMFBR

    SciTech Connect

    Marchertas, A.H.

    1982-09-01

    A finite element computer code for the transient analysis of prestressed concrete reactor vessels (PCRVs) for LMFBR containment is described. The method assumes rotational symmetry of the structure. Time integration is by an explicit method. The quasistatic prestressing operation of the PCRV model is performed by a dynamic relaxation technique. The material model accounts for the crushing and tensile cracking in arbitrary direction in concrete and the elastic-plastic behavior of reinforcing steel. The variation of the concrete tensile cracking and compressive crushing limits with strain rate is taken into account. Relative slip is permitted between the concrete and tendons. Several example solutions are presented and compared with experimental results. These sample problems range from simply supported beams to small scale models of PCRV's. It is shown that the analytical methods correlate quite well with experimental results, although in the vicinity of the failure load the response of the models tend to be quite sensitive to input parameters.

  20. Key technological issues in LMFBR high-temperature structural design - the US perspective

    SciTech Connect

    Corum, J.M.

    1984-01-01

    The purpose of this paper is: (1) to review the key technological issues in LMFBR high-temperature structural design, particularly as they relate to cost reduction; and (2) to provide an overview of activities sponsored by the US Department of Energy to resolve the issues and to establish stable, standardized, and defensible structural design methods and criteria. Specific areas of discussion include: weldments, structural validation tests, simplified design analysis procedures, design procedures for piping, validation of the methodology for notch-like geometries, improved life assessment procedures, thermal striping, extension of the methodology to new materials, and ASME high-temperature Code reform needs. The perceived problems and needs in each area are discussed, and the current status of related US activities is given.

  1. Some Implications of the Three Mile Island Accident for LMFBR Safety and Licensing: The Design Basis Issue

    DTIC Science & Technology

    1980-08-01

    usually leads to a construction license. The PSAR, along with support- ing documentation, a set of technical specifications, a preoperational test...IV. LICENSING AND SAFETY OF LMFBRs The recent experience with licensing an LMFBR has been limited to the Fast Flux Test Facility ( FFTF ) in...Washington state and the Clinch River Breeder Reactor (CRBR) in Tennessee. FFTF is unique because it is a test facility constructed on federal land and as

  2. Calculation of Doses Due to Accidentally Released Plutonium From An LMFBR

    SciTech Connect

    Fish, B.R.

    2001-08-07

    Experimental data and analytical models that should be considered in assessing the transport properties of plutonium aerosols following a hypothetical reactor accident have been examined. Behaviors of released airborne materials within the reactor containment systems, as well as in the atmosphere near the reactor site boundaries, have been semiquantitatively predicted from experimental data and analytical models. The fundamental chemistry of plutonium as it may be applied in biological systems has been used to prepare models related to the intake and metabolism of plutonium dioxide, the fuel material of interest. Attempts have been made to calculate the possible doses from plutonium aerosols for a typical analyzed release in order to evaluate the magnitude of the internal exposure hazards that might exist in the vicinity of the reactor after a hypothetical LMFBR (Liquid-Metal Fast Breeder Reactor) accident. Intake of plutonium (using data for {sup 239}Pu as an example) and its distribution in the body were treated parametrically without regard to the details of transport pathways in the environment. To the extent possible, dose-response data and models have been reviewed, and an assessment of their adequacy has been made so that recommended or preferred practices could be developed.

  3. Estimate of the local cladding overheating caused by pin bundle distortion in an LMFBR assembly

    SciTech Connect

    Khan, E.U.; Rector, D.R.; Fort, J.M.; Patton, E.M.

    1983-02-01

    This paper presents a conservative estimate of the cladding temperature increase (over nominal temperature) caused by a bundle-duct interference of 100 mils (0 to 1 in.) in a typical LMFBR pin bundle. Parameters affecting global and local heating that is caused by bundle-duct interaction (BDI) are described. The highlights and shortcomings of previous work on the subject are discussed. The geometry of the distorted bundle is conservatively obtained by linearly superimposing calculated local distortions onto global distortions obtained from a bundle compression test. Significant local reduction in the area of hot the channel is predicted. The edge pins are expected to contact the duct wall, but no pin-to-pin contact is predicted. The thermal-hydraulic analysis is done in two steps. First, the COBRA-WC Code is used to determine the subchannel temperature distribution. Second, based on coolant flow velocity measurements in a scaled (6X) model of a distorted pin bundle, the cladding temperature at the contact is predicted as a function of the contact width.

  4. Progress report on LLTR Series II Test A-2 (Part 1). [LMFBR

    SciTech Connect

    Freede, W.J.; Neely, H.H.

    1980-01-01

    This document contains a complete set of valid and final digital and analog data plots for LLTR Series II, Test A-2. Included is an Accuracy Statement regarding this data as required by Revision 0 of the GE Test Request, Specification No. 23A2062. The Series II, Sodium-Water Reaction Test A-2 was performed in the Large Leak Test Rig (LLTR) at the Energy Technology Engineering Center (ETEC). This was the third of three planned double-edged guillotine (DEG) rupture tests of a single tube which will be followed by a number of small leak tests. The test article is the LLTI which is a full-size diameter internals, shortened in length and prototypic of the CRBR steam generator. It is installed in the Large Leak Test Vessel (LLTV). The overall test program was formulated by General Electric (GE) as Test Requester to establish steam generator design and to verify analytical models/codes to estimate the effect of large leak accidents in an LMFBR demonstration plant steam generator and system.

  5. Theory and use of GIRAFFE for analysis of decay characteristics of delayed-neutron precursors in an LMFBR

    SciTech Connect

    Gross, K. C.

    1980-07-01

    The application of the computer code GIRAFFE (General Isotope Release Analysis For Failed Elements) written in FORTRAN IV is described. GIRAFFE was designed to provide parameter estimates of the nonlinear discrete-measurement models that govern the transport and decay of delayed-neutron precursors in a liquid-metal fast breeder reactor (LMFBR). The code has been organized into a set of small, relatively independent and well-defined modules to facilitate modification and maintenance. The program logic, the numerical techniques, and the methods of solution used by the code are presented, and the functions of the MAIN program and of each subroutine are discussed.

  6. Constitutive correlations for wire-wrapped subchannel analysis under forced and mixed convection conditions. Part 1. [LMFBR

    SciTech Connect

    Cheng, S.K.; Todreas, N.E.

    1984-08-01

    A simple subchannel analysis method based on the ENERGY series of codes, ENERGY-IV, has been established for predicting the temperature field in a single isolated wire-wrapped Liquid Metal Fast Breeder Reactor (LMFBR) subassembly under steady state forced and mixed convection conditions. The ENERGY-IV is a totally empirical code employed for fast running purposes and requires well calibrated lead length averaged input parameters to achieve satisfactory predictions. These input parameters were identified to be the inlet flow split parameters, the subchannel friction factors, the interchannel mixing parameters, the conduction shape factor, and the transverse velocity at the edge gap. Experiments were performed in a 37-pin wire-wrapped rod bundle with a geometry between that of a typical LMFBR fuel subassembly and blanket subassembly for filling the gap in the available data base for the input parameters. The isokinetic extraction method for measuring subchannel velocity, the pitot-static probe for measuring pressure drop, and the salt tracer injection method for estimating the interchannel mixing, were used in these experiments.

  7. COBRA-WC: a version of COBRA for single-phase multiassembly thermal hydraulic transient analysis. [LMFBR

    SciTech Connect

    George, T.L.; Basehore, K.L.; Wheeler, C.L.; Prather, W.A.; Masterson, R.E.

    1980-07-01

    The objective of this report is to provide the user of the COBRA-WC (Whole Core) code a basic understanding of the code operation and capabilities. Included in this manual are the equations solved and the assumptions made in their derivations, a general description of the code capabilities, an explanation of the numerical algorithms used to solve the equations, and input instructions for using the code. Also, the auxiliary programs GEOM and SPECSET are described and input instructions for each are given. Input for COBRA-WC sample problems and the corresponding output are given in the appendices. The COBRA-WC code has been developed from the COBRA-IV-I code to analyze liquid Metal Fast Breeder Reactor (LMFBR) assembly transients. It was specifically developed to analyze a core flow coastdown to natural circulation cooling.

  8. D10 experiment: coolability of UO/sub 2/ debris in sodium with downward heat removal. [LMFBR

    SciTech Connect

    Mitchell, G.W.; Ottinger, C.A.; Meister, H.

    1984-12-01

    The LMFBR Debris Coolability Program at Sandia National Laboratories investigates the coolability of particle beds which may form following a severe accident involving core disassembly in a nuclear reactor. The D series experiments utilize fission heating of fully enriched UO/sub 2/ particles submerged in sodium to realistically simulate decay heating. The D10 experiment is the first in the series to study the effects of bottom cooling of the debris that could be provided in an actual accident condition by structural materials onto which the debris might settle. Additionally, the D10 experiment was designed to achieve maximum temperatures in the debris approaching the melting point of UO/sub 2/. The experiment was successfully operated for over 50 hours and investigated downward heat removal in a packed bed at specific powers of 0.16 to 0.58 W/g. Dryout in the debris was achieved at powers from 0.42 to 0.58 W/g. Channels were induced in the bed and channeled bed dryout was achieved at powers of 1.06 to 1.77 W/g. Maximum temperatures in excess of 2500/sup 0/C were attained.

  9. Development of ultrasonic thermometry for high-temperature high-resolution temperature profiling applications in LMFBR safety research

    NASA Astrophysics Data System (ADS)

    Field, M. E.

    1986-05-01

    Ultrasonic thermometry was developed as a high temperature profiling diagnostic for use in the Liquid Metal Fast Breeder Reactor (LMFBR) Debris Coolability Program at Sandia National Laboratories. These instruments were used successfully in the DC series experiments and the D10 experiment. Temperatures approaching 3000 C with spatial resolution of 10 mm and indicated temperature gradients of 700 C/cm were measured. Instruments were operated in molten sodium, molten steel, and molten UO2 environments. Up to 14 measurement zones on a single instrument in molten sodium were used with 12 mm and 15 mm spatial resolution. Hermetically sealed units operating at elevated temperatures were used. Post-test examination revealed very little systematic calibration drifts (less than 10 C) with random drifts occuring with less than 40 C standard deviation in a 10 to 12 mm measured zone. The stability of the system varies from +/- 1 C to +/- 15 C depending on the sensor design constraints for a particular application. Doped tungsten sensors were developed to permit operation of total measurement zone length of 30 cm at temperatures above 2500 C.

  10. Graphical and tabular summaries of decay characteristics for once-through PWR, LMFBR, and FFTF fuel cycle materials. [Spent fuel, high-level waste fuel can scrap

    SciTech Connect

    Croff, A.G.; Liberman, M.S.; Morrison, G.W.

    1982-01-01

    Based on the results of ORIGEN2 and a newly developed code called ORMANG, graphical and summary tabular characteristics of spent fuel, high-level waste, and fuel assembly structural material (cladding) waste are presented for a generic pressurized-water reactor (PWR), a liquid-metal fast breeder reactor (LMFBR), and the Fast Flux Test Facility (FFTF). The characteristics include radioactivity, thermal power, and toxicity (water dilution volume). Given are graphs and summary tables containing characteristic totals and the principal nuclide contributors as well as graphs comparing the three reactors for a single material and the three materials for a single reactor.

  11. Coherence and Polarization Properties of Far Fields Generated by Quasi-Homogeneous Planar Electromagnetic Sources (Postprint)

    DTIC Science & Technology

    2005-02-03

    the explicit dependence of all he parameters on the frequency. In order that the elec- romagnetic Gaussian Schell - model source generated by eans of the...the far field gener- ted by a planar electromagnetic Gaussian Schell - model ource are given by the expressions s1 rs, = xx 2 exp− xx 2 k2 2/2...uniformly polarized, quasi- omogeneous Gaussian Schell - model source, which is haracterized by a cross-spectral density matrix J rs ,rs , whose

  12. Quasi-homogeneous hydrogenation with platinum and palladium nanoparticles stabilized by dendritic core-multishell architectures.

    PubMed

    Schwarze, Michael; Keilitz, Juliane; Nowag, Sabrina; Parapat, Riny Y; Haag, Rainer; Schomäcker, Reinhard

    2011-05-17

    Platinum and palladium nanoparticles, supported and stabilized by polymeric core-shell architectures, proved to be active catalysts for hydrogenation reactions. Here, two different reactions were used as probes to investigate the influence of the polymeric support: the hydrogenation of α-methyl styrene (AMS) to cumene and the partial hydrogenation of 1,5-cyclooctadiene (COD). We found that the stability of the nanoparticles and the rate of reaction are higher in the presence of a hydrophobic octadecyl shell within a three-shell polymer system. The kinetic study of AMS hydrogenation showed much higher activities for palladium nanoparticles than for platinum nanoparticles, and the obtained results (e.g., 35 kJ/mol for the activation energy) are of the same order of magnitude as reported earlier for palladium supported on alumina. A methanol/n-heptane biphasic mixture was tested for catalyst recycling and allowed for highly efficient catalyst separation with very low metal leaching.

  13. Crossflow force transducer. [LMFBR

    SciTech Connect

    Mulcahy, T M

    1982-05-01

    A force transducer for measuring lift and drag coefficients for a circular cylinder in turbulent water flow is presented. In addition to describing the actual design and construction of the strain-gauged force- ring based transducer, requirements for obtained valid fluid force test data are discussed, and pertinent flow test experience is related.

  14. Combustion Engineering, Inc. [LMFBR

    SciTech Connect

    Not Available

    1980-01-01

    Four (4) 3 '' O.D. x 0.470'' nominal wall thickness (NWT) hot rotary pierced/roll reduced modified AOD/ESR tube hollows were cold pilger reduced through one pass to 2'' O.D. x 0.250'' NWT tubing. Two (2) additional hollows of same size and process history were cold pilger reduced through one pass to 2 1/8'' O.D. x 0.200'' NWT. Six (6) 3 3/4'' O.D. x 0.600'' NWT hot extruded tube hollows were cold pilger reduced through two passes to 2'' O.D. x 0.250'' NWT tubing. Four of the extrusions represented duplex AOD/ESR melting practice and two extrusions represented AOD melting practice. Twelve (12) pieces of 2 1/8'' O.D. x 0.200'' NWT x approx. 9' long tubing were final heat treated, straightened, and ultrasonically tested. Twelve (12) more pieces of 2 1/8'' O.D. tubing have been solution austenitized (1177/sup 0/C) and are to be reaustenitized (1066/sup 0/C), tempered (760/sup 0/C), straightened, and ultrasonically inspected. All 2'' O.D. x 0.250'' NWT tubing is in the solution austenitized condition. Creep and stress rupture testing has continued on aged material from CarTech heat 91887 and on unaged material from CarTech heat 30182A.

  15. Vibrating fuel grapple. [LMFBR

    DOEpatents

    Chertock, A.J.; Fox, J.N.; Weissinger, R.B.

    A reactor refueling method is described which utilizes a vibrating fuel grapple for removing spent fuel assemblies from a reactor core. It incorporates a pneumatic vibrator in the grapple head which allows additional withdrawal capability without exceeding the allowable axial force limit. The only moving part in the vibrator is a steel ball, pneumatically driven by a gas, such as argon, around a track, with centrifugal force created by the ball being transmitted through the grapple to the assembly handling socket.

  16. Sealing coupling. [LMFBR

    DOEpatents

    Pardini, J.A.; Brubaker, R.C.; Rusnak, J.J.

    1982-09-20

    Disclosed is a remotely operable releasable sealing coupling which provides fluid-tight joinder of upper and a lower conduit sections. Each conduit section has a concave conical sealing surface adjacent its end portion. A tubular sleeve having convex spherical ends is inserted between the conduit ends to form line contact with the concave conical end portions. An inwardly projecting lip located at one end of the sleeve cooperates with a retaining collar formed on the upper pipe end to provide swivel capture for the sleeve. The upper conduit section also includes a tapered lower end portion which engages the inside surface of the sleeve to limit misalignment of the connected conduit sections.

  17. Concept Mapping

    ERIC Educational Resources Information Center

    Technology & Learning, 2005

    2005-01-01

    Concept maps are graphical ways of working with ideas and presenting information. They reveal patterns and relationships and help students to clarify their thinking, and to process, organize and prioritize. Displaying information visually--in concept maps, word webs, or diagrams--stimulates creativity. Being able to think logically teaches…

  18. Concept Overview.

    ERIC Educational Resources Information Center

    Sandmann, B. J.

    1988-01-01

    Four teaching techniques were used to enhance conceptual learning and to increase student performance in a course in physical-chemical principles at the School of Pharmacy of the University of Missouri-Kansas City. One of the techniques, "concept overview," is described. (MLW)

  19. Nonuniform Liouville transformers for quasi-homogeneous optical fields. Final technical report, September 25, 1989--January 22, 1993

    SciTech Connect

    Jannson, T.

    1993-03-01

    During the last two decades, there have been dramatic improvements in the development of optical sources. Examples of this development range from semiconductor laser diodes to free electron beam lasers and synchrotron radiation. Before these developments, standards for the measurement of basic optical parameters (quantities) were less demanding. Now, however, there is a fundamental need for new, reliable methods for providing fast quantitative results for a very broad variety of optical systems and sources. This is particularly true for partially coherent optical beams, since all optical sources are either fully or partially spatially coherent (including Lambertian sources). Until now, there has been no satisfactory solution to this problem. During the last two decades, however, the foundations of physical radiometry have been developed by Walther, Wolf and co-workers. By integrating physical optics, statistical optics and conventional radiometry, this body of work provides necessary tools for the evaluation of radiometric quantities for partially coherent optical beams propagating through optical systems. In this program, Physical Optics Corporation (POC) demonstrated the viability of such a radiometric approach for the specific case of generalized energy concentrators called Liouville transformers. We believe that this radiometric approach is necessary to fully characterize any type of optical system since it takes into account the partial coherence of radiation. 90 refs., 57 figs., 4 tabs.

  20. Application of a unified deformation-rate law to stress relaxation of AISI Type 316 stainless steel. [LMFBR

    SciTech Connect

    DiMelfi, R.J.

    1983-01-01

    A unified deformation rate law is presented and its use at describing stress-relaxation in cladding material is examined. An equation is derived based on the classical theory of rate processes for type 316 stainless steel (the reference fuel-cladding material). In this framework, a strain-rate law is evolved from the concept that plastic deformation is controlled by the rate at which dislocations move past obstacles by thermal activation.

  1. Current Concepts in Conception Control

    PubMed Central

    Ringrose, C. A. Douglas

    1963-01-01

    The progressive increase in world population has become a most urgent global problem in recent years. Man has, however, been interested in controlling his reproductivity at the family level for many centuries. Historical aspects of this saga are reviewed. The modern era of conception control was ushered in by Makepeace et al. in 1937 when ovulation inhibition by progesterone was demonstrated. Confirmation of this by Pincus and associates, and development of the potent oral progestational agents, the 19-norsteroids, have made efficient reliable contraception a reality. Experience with one of these agents (Ortho-Novum, 2 mg.) in 115 patients through 805 cycles is presented. Conception control was 100% effective at this dosage. Side effects were minimal. Only three of the women discontinued the tablets because of these effects. All but five in this group of 115 preferred the oral contraceptives to methods previously employed. PMID:13973987

  2. Concept Mapping

    PubMed Central

    Brennan, Laura K.; Brownson, Ross C.; Kelly, Cheryl; Ivey, Melissa K.; Leviton, Laura C.

    2016-01-01

    Background From 2003 to 2008, 25 cross-sector, multidisciplinary community partnerships funded through the Active Living by Design (ALbD) national program designed, planned, and implemented policy and environmental changes, with complementary programs and promotions. This paper describes the use of concept-mapping methods to gain insights into promising active living intervention strategies based on the collective experience of community representatives implementing ALbD initiatives. Methods Using Concept Systems software, community representatives (n=43) anonymously generated actions and changes in their communities to support active living (183 original statements, 79 condensed statements). Next, respondents (n=26, from 23 partnerships) sorted the 79 statements into self-created categories, or active living intervention approaches. Respondents then rated statements based on their perceptions of the most important strategies for creating community changes (n=25, from 22 partnerships) and increasing community rates of physical activity (n=23, from 20 partnerships). Cluster analysis and multidimensional scaling were used to describe data patterns. Results ALbD community partnerships identified three active living intervention approaches with the greatest perceived importance to create community change and increase population levels of physical activity: changes to the built and natural environment, partnership and collaboration efforts, and land-use and transportation policies. The relative importance of intervention approaches varied according to subgroups of partnerships working with different populations. Conclusions Decision makers, practitioners, and community residents can incorporate what has been learned from the 25 community partnerships to prioritize active living policy, physical project, promotional, and programmatic strategies for work in different populations and settings. PMID:23079266

  3. Technium concept

    NASA Astrophysics Data System (ADS)

    Clement, Marc; Davies, Stephen

    2002-05-01

    Traditionally the economy of Wales has been based on the coal and steel industries. Recently, Wales has elected its own National Assembly and together with the Welsh Development Agency (WDA) and through a Regional Technology Plan, has prioritized the creation and development of a knowledge based economy. The culture of Wales has always placed emphasis on education and for a small nation, has a University sector with an excellent reputation for advanced research. The WDA and the University of Wales Swansea came together to establish Technium, which is an unique concept designed to bridge the gap between advanced University research and commercial exploitation. Technium was co-funded by the WDA and the European Regional Development Fund. The project is seen as the first phase of creating a network of sector specific Techniums across the country, all linked via state of the art telecomm-infrastructure to University centers of research excellence. This paper will describe two case studies, both in the Optics/Photonics field, of research centers being established in Technium by blue chip international companies. Those companies having located in Technium specifically because of the links to high quality university research. One company is Agilent Technologies Inc., USA) a global leader in Optoelectronic components. The second company, ICN Pharmaceuticals Inc, design and develop optical devices to be used in conjunction with pharmaceuticals for the treatment of a range of diseases. Working closely with the WDA and the University of Wales Swansea, these and other companies will pursue product development, sponsor postgraduate research and generate intellectual capital that will benefit the company, students and the region alike.

  4. SCIENCE BRIEF: ADVANCED CONCEPTS

    EPA Science Inventory

    Research on advanced concepts will evaluate and demonstrate the application of innovative infrastructure designs, management procedures and operational approaches. Advanced concepts go beyond simple asset management. The infusion of these advanced concepts into established wastew...

  5. Reactor vessel support system. [LMFBR

    DOEpatents

    Golden, M.P.; Holley, J.C.

    1980-05-09

    A reactor vessel support system includes a support ring at the reactor top supported through a box ring on a ledge of the reactor containment. The box ring includes an annular space in the center of its cross-section to reduce heat flow and is keyed to the support ledge to transmit seismic forces from the reactor vessel to the containment structure. A coolant channel is provided at the outside circumference of the support ring to supply coolant gas through the keyways to channels between the reactor vessel and support ledge into the containment space.

  6. Concepts in Change

    ERIC Educational Resources Information Center

    Rusanen, Anna-Mari; Poyhonen, Samuli

    2013-01-01

    In this article we focus on the concept of concept in conceptual change. We argue that (1) theories of higher learning must often employ two different notions of concept that should not be conflated: psychological and scientific concepts. The usages for these two notions are partly distinct and thus straightforward identification between them is…

  7. Concepts in Communication.

    ERIC Educational Resources Information Center

    Trent, Jimmie D.; And Others

    This book is a collection of ideas and information, gathered from various sources, which should aid college students in formulating their own methods of improving communication. The four main sections of the book are "Concepts of Communication,""Concepts of Source and Message,""Concepts of Communication Criticism," and "Concepts of Interpersonal…

  8. New concepts for Reynolds stress transport equation modeling of inhomogeneous flows

    NASA Technical Reports Server (NTRS)

    Perot, J. Blair; Moin, Parviz

    1993-01-01

    The ability to model turbulence near solid walls and other types of boundaries is important in predicting complex engineering flows. Most turbulence modeling has concentrated either on flows which are nearly homogeneous or isotropic, or on turbulent boundary layers. Boundary layer models usually rely very heavily on the presence of mean shear and the production of turbulence due to that mean shear. Most other turbulence models are based on the assumption of quasi-homogeneity. However, there are many situations of engineering interest which do not involve large shear rates and which are not quasi-homogeneous or isotropic. Shear-free turbulent boundary layers are the prototypical example of such flows, with practical situations being separation and reattachment, bluff body flow, high free-stream turbulence, and free surface flows. Although these situations are not as common as the variants of the flat plate turbulent boundary layer, they tend to be critical factors in complex engineering situations. The models developed are intended to extend classical quasi-homogeneous models into regions of large inhomogeneity. These models do not rely on the presence of mean shear or production, but are still applicable when those additional effects are included. Although the focus is on shear-free boundary layers as tests for these models, results for standard shearing boundary layers are also shown.

  9. Creative Concept Mapping.

    ERIC Educational Resources Information Center

    Brown, David S.

    2002-01-01

    Recommends the use of concept mapping in science teaching and proposes that it be presented as a creative activity. Includes a sample lesson plan of a potato stamp concept mapping activity for astronomy. (DDR)

  10. Subnational variations in conceptions.

    PubMed

    Wood, R

    1996-01-01

    Conception statistics are derived from information collected at the registration of live births, still births, and legal abortions. This article looks at how conception rates vary across England and Wales using the 1991 ONS area classification of DHAs (Population Trends 79). A comparison is made between age-specific conception rates for different area classification groups in 1993, and changes between 1983 and 1993 are examined. Correlations between certain social and economic factors and conception rates are also analysed.

  11. Conceptions of Ability.

    ERIC Educational Resources Information Center

    Jagacinski, Carolyn M.; Nicholls, John G.

    Two different conceptions of ability are proposed. The first conception of ability is more differentiated and generally employed by adults and older children. Here ability level is defined with reference to the performance of others assuming that optimum effort was employed. High ability means higher than others. The second conception of ability…

  12. Threshold Concepts in Biochemistry

    ERIC Educational Resources Information Center

    Loertscher, Jennifer

    2011-01-01

    Threshold concepts can be identified for any discipline and provide a framework for linking student learning to curricular design. Threshold concepts represent a transformed understanding of a discipline, without which the learner cannot progress and are therefore pivotal in learning in a discipline. Although threshold concepts have been…

  13. Concept Image Revisited

    ERIC Educational Resources Information Center

    Bingolbali, Erhan; Monaghan, John

    2008-01-01

    Concept image and concept definition is an important construct in mathematics education. Its use, however, has been limited to cognitive studies. This article revisits concept image in the context of research on undergraduate students' understanding of the derivative which regards the context of learning as paramount. The literature, mainly on…

  14. Resilience - A Concept

    DTIC Science & Technology

    2016-04-05

    Image designed by Diane Fleischer Resilience—A CONCEPT Col Dennis J. Rensel, USAF (Ret.) Resilience takes on many definitions and ideas depending...2015, Vol. 22 No. 3 : 294–324 A Publication of the Defense Acquisition University http://www.dau.mil Resilience as a term has as many definitions as...people who talk about it. What if resiliency is treated as a concept? How do you measure a concept? In reviewing many definitions , “each [ definition

  15. Evolving Ethical Concepts

    ERIC Educational Resources Information Center

    Potter, Van Rensselaer

    1977-01-01

    Discusses the role of the scientist in changing ethical concepts from simple interpersonal and theological imperatives towards "survival imperatives that must form the core of environmental bioethics." (CS)

  16. Core Concepts of Kinesiology.

    ERIC Educational Resources Information Center

    Hudson, Jackie L.

    1995-01-01

    Core concepts of kinesiology are the basis of communication about movement that facilitate progression of skill levels. The article defines and exemplifies each of 10 core concepts: range of motion, speed of motion, number of segments, nature of segments, balance, coordination, compactness, extension at release/contact, path of projection, and…

  17. The Self Concept.

    ERIC Educational Resources Information Center

    Fitzgibbon, Ann

    The purpose of this paper is to increase awareness of the self concept as a variable, to indicate what is known about the self concept from existing research, to discuss its importance to the school and its effect on learning, and to offer a method of assessment which is tied to a definition arbitrarily made as a starting point for researchers. A…

  18. Avionics technology - system concepts

    NASA Technical Reports Server (NTRS)

    Bull, J. S.; Huntoon, R. B.

    1984-01-01

    Avionics System Concepts to meet technology needs of advanced helicopter integrated cockpit design are identified. Specific avionics system concepts which should be conducted and/or support by NASA to most effectively aid industry in advanced helicopter integrated cockpit design are also identified. Candidate Missions and Mission Requirements to meet technology needs are considered.

  19. Values Concepts and Techniques.

    ERIC Educational Resources Information Center

    National Education Association, Washington, DC.

    This book contains 29 articles for elementary and secondary teachers dealing with fundamental concepts and teaching techniques in values education. Part one of the book deals with concepts. Louis E. Raths examines valuing and its relationship to freedom and intelligence. The cognitive developmental approach to moral education is discussed by…

  20. New Concepts of Work.

    ERIC Educational Resources Information Center

    Canadian Council on Social Development, Ottawa (Ontario).

    The two-day Canadian conference focused on the topics: "Why are new concepts of work emerging?" and "How can we encourage desirable new work concepts in our society?" Following an introductory summary by David P. Ross, Stephen Peitchinis (Dean, School of Business Administration, University of Calgary) presented the economic…

  1. Learning Our Concepts

    ERIC Educational Resources Information Center

    Laverty, Megan J.

    2009-01-01

    Richard Stanley Peters appreciates the centrality of concepts for everyday life, however, he fails to recognize their pedagogical dimension. He distinguishes concepts employed at the first-order (our ordinary language-use) from second-order conceptual clarification (conducted exclusively by academically trained philosophers). This distinction…

  2. Integral Fast Reactor concept

    SciTech Connect

    Till, C.E.; Chang, Y.I.

    1986-01-01

    The Integral Fast Reactor (IFR) is an innovative LMR concept, being developed at Argonne National Laboratory, that fully exploits the inherent properties of liquid metal cooling and metallic fuel to achieve breakthroughs in economics and inherent safety. This paper describes key features and potential advantages of the IFR concept, technology development status, fuel cycle economics potential, and future development path.

  3. Data Transmission Concepts.

    ERIC Educational Resources Information Center

    Christenson, Chris

    1995-01-01

    Introduces some basic concepts related to the transmission of data from a computer to its peripherals to help distance educators make decisions regarding computer equipment purchases for their institutions. The following data transmission concepts are described: cables, serial and parallel, synchronous and asynchronous, bandwidth, and analog and…

  4. Thinking to Learn Concepts.

    ERIC Educational Resources Information Center

    Parker, Walter C.

    1988-01-01

    States that programs which link the teaching of thinking with content have the greatest instructional value. Presents a concept formation lesson, based on the works of Taba (1967) and Ehrenberg (1978), which requires students to learn a concept by studying several examples and noting their similarities and differences. Includes a sample…

  5. Teach Concepts, Not Words.

    ERIC Educational Resources Information Center

    Williamson, Leon E.

    Since concepts are the mental divisions man makes among the concrete and abstract phenomena of his environment so he may generate, maneuver, and control their relationships in a manner ot satisfy his physical, emotional, social, and aesthetic needs, concepts should be the vortex of intelligence. Too often students are taught as if they lack a…

  6. Emerging SPS Concepts

    NASA Technical Reports Server (NTRS)

    Hanley, G.; Woodcock, G. R.

    1980-01-01

    Four technologies were evaluated to determine their effect on Satellite Power System concepts. Two of these technologies, solid-state power amplifiers and magnetrons, are replacements for the Klystrons used for dc to RF conversion on the satellite. A third technology, laser power transmission, transmits the energy at laser frequencies rather than microwave frequencies. The fourth technology, multibandgap solar cells, has the promise of significantly increased solar to dc conversion efficienty as compared to the reference-concept silicon and gallium arsenide solar cells. The design characteristics of concepts resulting from application of these technologies are summarized.

  7. Advanced concepts for acceleration

    SciTech Connect

    Keefe, D.

    1986-07-01

    Selected examples of advanced accelerator concepts are reviewed. Such plasma accelerators as plasma beat wave accelerator, plasma wake field accelerator, and plasma grating accelerator are discussed particularly as examples of concepts for accelerating relativistic electrons or positrons. Also covered are the pulsed electron-beam, pulsed laser accelerator, inverse Cherenkov accelerator, inverse free-electron laser, switched radial-line accelerators, and two-beam accelerator. Advanced concepts for ion acceleration discussed include the electron ring accelerator, excitation of waves on intense electron beams, and two-wave combinations. (LEW)

  8. Blazars: Artist Conception

    NASA Video Gallery

    What astronomers once thought were two blazar families may in fact be one, as shown in this artist's concept. Energy stored in the black hole during its salad days of intense accretion may later be...

  9. Common tester platform concept.

    SciTech Connect

    Hurst, Michael James

    2008-05-01

    This report summarizes the results of a case study on the doctrine of a common tester platform, a concept of a standardized platform that can be applicable across the broad spectrum of testing requirements throughout the various stages of a weapons program, as well as across the various weapons programs. The common tester concept strives to define an affordable, next-generation design that will meet testing requirements with the flexibility to grow and expand; supporting the initial development stages of a weapons program through to the final production and surveillance stages. This report discusses a concept investing key leveraging technologies and operational concepts combined with prototype tester-development experiences and practical lessons learned gleaned from past weapons programs.

  10. Decoding Astronomical Concepts

    ERIC Educational Resources Information Center

    Durisen, Richard H.; Pilachowski, Catherine A.

    2004-01-01

    Two astronomy professors, using the Decoding the Disciplines process, help their students use abstract theories to analyze light and to visualize the enormous scale of astronomical concepts. (Contains 5 figures.)

  11. The AERA Concept.

    DTIC Science & Technology

    1981-03-24

    electrgnic tabular displays ( ETABS ). - , This concept document was prepared by a team of ATC experts to review prior work, the on-going AERA program, and to...Address Beacon System (DABS), trajectory modeling and planning algorithms, and electronic tabular displays ( ETABS ). This concept document was...capability, and a Flight Management System. The development of AERA requires major efforts in system design and software and man-machine interface

  12. Concept analysis: resilience.

    PubMed

    Garcia-Dia, Mary Joy; DiNapoli, Jean Marie; Garcia-Ona, Leila; Jakubowski, Rita; O'Flaherty, Deirdre

    2013-12-01

    This paper will systematically analyze the concept of resilience using an integrated review of literature. The historical perspective, attributes, antecedents, and consequences of resilience will be reviewed. A theoretical and operational definition will be provided. The Walker and Avant method will be used to describe the cases. Finally, the use of concept map will capture the relationships among the attributes, antecedents, consequences, and empirical indicators through clustering and chaining.

  13. [Comfort: a concept analysis].

    PubMed

    Tsai, Jia-Ling; Lee, Ya-Ling; Hu, Wen-Yu

    2012-02-01

    Comfort is an important concept and core value of nursing. The defining attributes, antecedents and consequences of comfort need further analysis and exploration, even though the concept of comfort has been addressed previously in nursing literature. We employed the strategies of concept analysis as described by Walker&Avant (2005) to analyze the concept of comfort. The defining attributes of comfort include: 1) effective communication; 2) family and meaningful relationships; 3) maintaining functionality; 4) self-characteristics; 5) physical symptom relief, states, and interventions; 6) psychological, spiritual activities and states; and 7) a sense of safety and security. Antecedents consist of discomfort, distress and suffering. Consequences consist of (1) met/satisfied needs; (2) increased sense of control; (3) sense of inner peace; (4) a pleasant experience; (5) feeling cared for; (6) relief of symptoms; (7) reduced suffering; (8) decreased disequilibrium; and (9) absence of discomfort. We also outline the construction of cases, empirical references and comfort measurement tools. Analysis found comfort to have multiple dimensions and confirmed it as a clinical issue that should receive greater emphasis and valuation. Findings are hoped to increase nurse understanding of the concept of comfort and enable nurses to evaluate level of comfort and follow up on variations in such using empirical tools. Concept analysis can guide further comfort related interventions and research to benefit patients.

  14. [Mindfulness: A Concept Analysis].

    PubMed

    Chen, Tsai-Ling; Chou, Fan-Hao; Wang, Hsiu-Hung

    2016-04-01

    "Mindfulness" is an emerging concept in the field of healthcare. Ranging from stress relief to psychotherapy, mindfulness has been confirmed to be an effective tool to help individuals manage depression, anxiety, obsessive-compulsive disorder, and other health problems in clinical settings. Scholars currently use various definitions for mindfulness. While some of these definitions overlap, significant differences remain and a general scholarly consensus has yet to be reached. Several domestic and international studies have explored mindfulness-related interventions and their effectiveness. However, the majority of these studies have focused on the fields of clinical medicine, consultation, and education. Mindfulness has rarely been applied in clinical nursing practice and no related systematic concept analysis has been conducted. This paper conducts a concept analysis of mindfulness using the concept analysis method proposed by Walker and Avant (2011). We describe the defining characteristics of mindfulness, clarify the concept, and confirm the predisposing factors and effects of mindfulness using examples of typical cases, borderline cases, related cases, and contrary case. Findings may provide nursing staff with an understanding of the concept of mindfulness for use in clinical practice in order to help patients achieve a comfortable state of body and mind healing.

  15. A Key Concept: Spatial Organization

    ERIC Educational Resources Information Center

    Kostrowicki, Jerzy

    1975-01-01

    The application of geography to spatial planning is discussed. Concepts presented include the regional concept, the typological concept, and spatial structure, spatial processes, and spatial organization. For address of journal see SO 504 028. (Author/RM)

  16. Concept Analysis: Music Therapy.

    PubMed

    Murrock, Carolyn J; Bekhet, Abir K

    2016-01-01

    Down through the ages, music has been universally valued for its therapeutic properties based on the psychological and physiological responses in humans. However, the underlying mechanisms of the psychological and physiological responses to music have been poorly identified and defined. Without clarification, a concept can be misused, thereby diminishing its importance for application to nursing research and practice. The purpose of this article was for the clarification of the concept of music therapy based on Walker and Avant's concept analysis strategy. A review of recent nursing and health-related literature covering the years 2007-2014 was performed on the concepts of music, music therapy, preferred music, and individualized music. As a result of the search, the attributes, antecedents, and consequences of music therapy were identified, defined, and used to develop a conceptual model of music therapy. The conceptual model of music therapy provides direction for developing music interventions for nursing research and practice to be tested in various settings to improve various patient outcomes. Based on Walker and Avant's concept analysis strategy, model and contrary cases are included. Implications for future nursing research and practice to use the psychological and physiological responses to music therapy are discussed.

  17. Space vehicle concepts

    NASA Technical Reports Server (NTRS)

    Tucker, Michael; Meredith, Oliver; Brothers, Bobby

    1986-01-01

    Several concepts of chemical-propulsion Space Vehicles (SVs) for manned Mars landing missions are presented. For vehicle sizing purposes, several specific missions were chosen from opportunities in the late 1990's and early 2000's, and a vehicle system concept is then described which is applicable to the full range of missions and opportunities available. In general, missions utilizing planetary opposition alignments can be done with smaller vehicles than those utilizing planetary opposition alignments. The conjunction missions have a total mission time of about 3 years, including a required stay-time of about 60 days. Both types of missions might be desirable during a Mars program, the opposition type for early low-risk missions and/or for later unmanned cargo missions, and the conjunction type for more extensive science/exploration missions and/or for Mars base activities. Since the opposition missions appeared to drive the SV size more severely, there were probably more cases examined for them. Some of the concepts presented utilize all-propulsive braking, some utilize and all aerobraking approach, and some are hybrids. Weight statements are provided for various cases. Most of the work was done on 0-g vehicle concepts, but partial-g and 1-g concepts are also provided and discussed. Several options for habitable elements are shown, such as large-diameter modules and space station (SS) types of modules.

  18. Creating Heliophysics Concept Maps

    NASA Astrophysics Data System (ADS)

    Ali, N. A.; Peticolas, L. M.; Paglierani, R.; Mendez, B. J.

    2011-12-01

    The Center for Science Education at University of California Berkeley's Space Sciences Laboratory is creating concept maps for Heliophysics and would like to get input from scientists. The purpose of this effort is to identify key concepts related to Heliophysics and map their progression to show how students' understanding of Heliophysics might develop from Kindergarten through higher education. These maps are meant to tie into the AAAS Project 2061 Benchmarks for Scientific Literacy and National Science Education Standards. It is hoped that the results of this effort will be useful for curriculum designers developing Heliophysics-related curriculum materials and classroom teachers using Heliophysics materials. The need for concept maps was identified as a result of product analysis undertaken by the NASA Heliophysics Forum Team. The NASA Science Education and Public Outreach Forums have as two of their goals to improve the characterization of the contents of the Science Mission Directorate and Public Outreach (SMD E/PO) portfolio (Objective 2.1) and assist SMD in addressing gaps in the portfolio of SMD E/PO products and project activities (Objective 2.2). An important part of this effort is receiving feedback from solar scientists regarding the inclusion of key concepts and their progression in the maps. This session will introduce the draft concept maps and elicit feedback from scientists.

  19. The concept of compartmentalisation.

    PubMed

    Scott, A; Zepeda, C; Garber, L; Smith, J; Swayne, D; Rhorer, A; Kellar, J; Shimshony, A; Batho, H; Caporale, V; Giovannini, A

    2006-12-01

    The rationale for establishing trade 'regions' and 'zones' is based on principles of epidemiological science and risk analysis that assess and manage animal disease risks so that the safety of trade can be ensured. However, the boundaries of geographical regions and zones may readily be breached through numerous epidemiological pathways. The concept of a 'compartment' extends the application of a 'risk boundary' beyond that of a geographical interface and considers all epidemiological factors that can contribute to the creation of an effective boundary. The fundamental requirement for application of either concept (regions/zones or compartments) is that the population considered for trade is maintained within management or geographical boundaries which allow clear epidemiological differentiation to be made between those animals and surrounding populations of higher risk. Seven factors are presented that an exporting country might use to guide the identification and documentation of a compartment. Additionally, the steps that would be undertaken to implement trade based on the compartmentalisation concept are discussed.

  20. New Mars vehicle concepts

    NASA Astrophysics Data System (ADS)

    Sherwood, Brent

    1993-02-01

    The paper briefly reviews the evolution of the Mars vehicle design concepts from 1952 to 1990, and the currently understood requirements, constraints, and options for manned Mars missions in the early decades of the 21st century. The most up-to-date integrated Mars vehicle concepts for crew-carrying transfer and excursion vehicles are presented together with the Mars descent-ascent mission phases. Particular attention is given to a reusable transfer ship, which is a modular vehicle launched to earth orbit on six 185 t-class boosters and assembled there robotically; it uses dual nuclear-thermal rocket engines and liquid hydrogen propellant. The lander concept is capable of supporting many kinds of surface missions anywhere on Mars.

  1. [Appraisal: a concept analysis].

    PubMed

    Kuo, Chia-Chi; Lin, Chiu-Chu; Ma, Shu-Ching

    2007-04-01

    Appraisal is a cognitive response by an individual facing an event within a given environment. When the individual has passed through a thought process that gives the event meaning, the coping process is finally completed. Coping heightens an individual's well-being. Negative appraisal will induce an emotional coping response and affect one's quality of life, mental state and health. Several researchers applied the concept of appraisal to their disciplines. The concept of appraisal, however, is poorly defined. This article applies the methodology outlined by Walker and Avant (1995) to analyze the concept of appraisal. The definition of appraisal, examples, and empirical references provided in this paper will be useful in nursing practice in relation to the role of appraisal in coping.

  2. Telepresence work system concepts

    NASA Technical Reports Server (NTRS)

    Jenkins, L. M.

    1985-01-01

    Telepresence has been used in the context of the ultimate in remote manipulation where the operator is provided with the sensory feedback and control to perform highly dexterous tasks. The concept of a Telepresence Work Station (TWS) for operation in space is described. System requirements, concepts, and a development approach are discussed. The TWS has the potential for application on the Space Shuttle, on the Orbit Maneuver Vehicle, on an Orbit Transfer Vehicle, and on the Space Station. The TWS function is to perform satellite servicing tasks and construction and assembly operations in the buildup of large spacecraft. The basic concept is a pair of dexterous arms controlled from a remote station by an operation with feedback. It may be evolved through levels of supervisory control to a smart adaptive robotic system.

  3. Robust Rocket Engine Concept

    NASA Technical Reports Server (NTRS)

    Lorenzo, Carl F.

    1995-01-01

    The potential for a revolutionary step in the durability of reusable rocket engines is made possible by the combination of several emerging technologies. The recent creation and analytical demonstration of life extending (or damage mitigating) control technology enables rapid rocket engine transients with minimum fatigue and creep damage. This technology has been further enhanced by the formulation of very simple but conservative continuum damage models. These new ideas when combined with recent advances in multidisciplinary optimization provide the potential for a large (revolutionary) step in reusable rocket engine durability. This concept has been named the robust rocket engine concept (RREC) and is the basic contribution of this paper. The concept also includes consideration of design innovations to minimize critical point damage.

  4. Field resonance propulsion concept

    NASA Technical Reports Server (NTRS)

    Holt, A. C.

    1979-01-01

    A propulsion concept was developed based on a proposed resonance between coherent, pulsed electromagnetic wave forms, and gravitational wave forms (or space-time metrics). Using this concept a spacecraft propulsion system potentially capable of galactic and intergalactic travel without prohibitive travel times was designed. The propulsion system utilizes recent research associated with magnetic field line merging, hydromagnetic wave effects, free-electron lasers, laser generation of megagauss fields, and special structural and containment metals. The research required to determine potential, field resonance characteristics and to evaluate various aspects of the spacecraft propulsion design is described.

  5. Revisiting the matricellular concept.

    PubMed

    Murphy-Ullrich, Joanne E; Sage, E Helene

    2014-07-01

    The concept of a matricellular protein was first proposed by Paul Bornstein in the mid-1990s to account for the non-lethal phenotypes of mice with inactivated genes encoding thrombospondin-1, tenascin-C, or SPARC. It was also recognized that these extracellular matrix proteins were primarily counter or de-adhesive. This review reappraises the matricellular concept after nearly two decades of continuous investigation. The expanded matricellular family as well as the diverse and often unexpected functions, cellular location, and interacting partners/receptors of matricellular proteins are considered. Development of therapeutic strategies that target matricellular proteins are discussed in the context of pathology and regenerative medicine.

  6. [Concepts of rational taxonomy].

    PubMed

    Pavlinov, I Ia

    2011-01-01

    The problems are discussed related to development of concepts of rational taxonomy and rational classifications (taxonomic systems) in biology. Rational taxonomy is based on the assumption that the key characteristic of rationality is deductive inference of certain partial judgments about reality under study from other judgments taken as more general and a priory true. Respectively, two forms of rationality are discriminated--ontological and epistemological ones. The former implies inference of classifications properties from general (essential) properties of the reality being investigated. The latter implies inference of the partial rules of judgments about classifications from more general (formal) rules. The following principal concepts of ontologically rational biological taxonomy are considered: "crystallographic" approach, inference of the orderliness of organismal diversity from general laws of Nature, inference of the above orderliness from the orderliness of ontogenetic development programs, based on the concept of natural kind and Cassirer's series theory, based on the systemic concept, based on the idea of periodic systems. Various concepts of ontologically rational taxonomy can be generalized by an idea of the causal taxonomy, according to which any biologically sound classification is founded on a contentwise model of biological diversity that includes explicit indication of general causes responsible for that diversity. It is asserted that each category of general causation and respective background model may serve as a basis for a particular ontologically rational taxonomy as a distinctive research program. Concepts of epistemologically rational taxonomy and classifications (taxonomic systems) can be interpreted in terms of application of certain epistemological criteria of substantiation of scientific status of taxonomy in general and of taxonomic systems in particular. These concepts include: consideration of taxonomy consistency from the

  7. Revisiting the matricellular concept

    PubMed Central

    Murphy-Ullrich, Joanne E.; Sage, E. Helene

    2015-01-01

    The concept of a matricellular protein was first proposed by Paul Bornstein in the mid-1990s to account for the non-lethal phenotypes of mice with inactivated genes encoding thrombospondin-1, tenascin-C, or SPARC. It was also recognized that these extracellular matrix proteins were primarily counter or de-adhesive. This review reappraises the matricellular concept after nearly two decades of continuous investigation. The expanded matricellular family as well as the diverse and often unexpected functions, cellular location, and interacting partners/receptors of matricellular proteins are considered. Development of therapeutic strategies that target matricellular proteins are discussed in the context of pathology and regenerative medicine. PMID:25064829

  8. Innatism, Concept Formation, Concept Mastery and Formal Education

    ERIC Educational Resources Information Center

    Winch, Christopher

    2015-01-01

    This article will consider the claim that the possession of concepts is innate rather than learned. Innatism about concept learning is explained through consideration of the work of Fodor and Chomsky. First, an account of concept formation is developed. Second the argument against the claim that concepts are learned through the construction of a…

  9. [Pleasure: Neurobiological conception and Freudian conception].

    PubMed

    Chenu, A; Tassin, J-P

    2014-04-01

    Despite many controversies the debate between psychoanalysis and neuroscience remains intense, all the more since the Freudian theory stands as a reference for a number of medical practitioners and faculty psychiatrists, at least in France. Instead of going on arguing we think that it may be more constructive to favour dialogue through the analysis of a precise concept developed in each discipline. The Freudian theory of pleasure, because it is based on biological principles, appears an appropriate topic to perform this task. In this paper, we aim at comparing Freud's propositions to those issued from recent findings in Neuroscience. Like all emotions, pleasure is acknowledged as a motivating factor in contemporary models. Pleasure can indeed be either rewarding when it follows satisfaction, or incentive when it reinforces behaviours. The Freudian concept of pleasure is more univocal. In Freud's theory, pleasure is assumed to be the result of the discharge of the accumulated excitation which will thus reduce the tension. This quantitative approach corresponds to the classical scheme that associates satisfaction and pleasure. Satisfaction of a need would induce both a decrease in tension and the development of pleasure. However, clinical contradictions to this model, such as the occasional co-existence between pleasure and excitation, drove Freud to suggest different theoretical reversals. Freud's 1905 publication, which describes how preliminary sexual pleasures contribute to an increased excitation and a sexual satisfaction, is the only analysis which provides an adapted answer to the apparent paradox of pleasure and excitation co-existence. Studies on the neurobiological mechanisms responsible for the development of pleasure may help to fill this gap in the Freudian theory. Activity of the mesolimbic dopaminergic pathway is strongly associated with the reward system. Experimental studies performed in animals have shown that increased dopaminergic activity in the

  10. Networks of Emotion Concepts

    PubMed Central

    Toivonen, Riitta; Kivelä, Mikko; Saramäki, Jari; Viinikainen, Mikko; Vanhatalo, Maija; Sams, Mikko

    2012-01-01

    The aim of this work was to study the similarity network and hierarchical clustering of Finnish emotion concepts. Native speakers of Finnish evaluated similarity between the 50 most frequently used Finnish words describing emotional experiences. We hypothesized that methods developed within network theory, such as identifying clusters and specific local network structures, can reveal structures that would be difficult to discover using traditional methods such as multidimensional scaling (MDS) and ordinary cluster analysis. The concepts divided into three main clusters, which can be described as negative, positive, and surprise. Negative and positive clusters divided further into meaningful sub-clusters, corresponding to those found in previous studies. Importantly, this method allowed the same concept to be a member in more than one cluster. Our results suggest that studying particular network structures that do not fit into a low-dimensional description can shed additional light on why subjects evaluate certain concepts as similar. To encourage the use of network methods in analyzing similarity data, we provide the analysis software for free use (http://www.becs.tkk.fi/similaritynets/). PMID:22276099

  11. Ares I concept illustration

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Shown is an illustration of the Ares I concept. The first stage will be a single, five-segment solid rocket booster derived from the space shuttle programs reusable solid rocket motor. The first stage is managed by NASA's Marshall Space Flight Center in Huntsville, Alabama for NASA's Constellation program.

  12. Ares I concept illustration

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Shown is a concept illustration of Ares I which is an in-line, two-stage rocket that will transport the Orion Crew Exploration Vehicle to low earth orbit. Orion will accommodate as many as six astronauts. The first stage will consist of the five-segment solid rocket booster.

  13. Ares I concept illustration

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Shown is a concept illustration of the Ares I crew launch vehicle, left, and Ares V cargo launch vehicle. Ares I will carry the Orion Crew Exploration Vehicle to space. Ares V will serve as NASA's primary vehicle for delivery of large-scale hardware to space.

  14. Learning Statistical Concepts

    ERIC Educational Resources Information Center

    Akram, Muhammad; Siddiqui, Asim Jamal; Yasmeen, Farah

    2004-01-01

    In order to learn the concept of statistical techniques one needs to run real experiments that generate reliable data. In practice, the data from some well-defined process or system is very costly and time consuming. It is difficult to run real experiments during the teaching period in the university. To overcome these difficulties, statisticians…

  15. Photoelectrochemistry: Introductory Concepts.

    ERIC Educational Resources Information Center

    Finklea, Harry O.

    1983-01-01

    Photoelectrochemistry is based on the semiconductor electrode. It is the semiconductor's ability to absorb light and convert it to electrical and/or chemical energy that forms the basis for the semiconductor liquid-junction solar cell. To understand how this occurs, solid-state physics concepts are discussed. (Author/JN)

  16. The Concept of Culture.

    ERIC Educational Resources Information Center

    Wilson, James Q.

    1993-01-01

    Explores the concept of culture as a factor in the well-being of children. Holding students accountable for their behavior, holding schools accountable for activities and achievements of students, and inducing parents to support their children in school require a cultural change in how we look at schooling. (SLD)

  17. Concept of Operations: Essence

    SciTech Connect

    Hutton, William J.

    2014-04-01

    This concept of operations is designed to give the reader a brief overview of the National Rural Electric Cooperative Association’s Essence project and a description of the Essence device design. The data collected by the device, how the data are used, and how the data are protected are also discussed in this document.

  18. Using Concept Cartoons

    ERIC Educational Resources Information Center

    Dabell, John

    2008-01-01

    Concept cartoons are cognitive drawings or "visual disagreements" that use a cartoon-style design to present mathematical conversations inside speech bubbles. The viewpoints portrayed are all different and it is this difference that acts as a catalyst for further conversations, as learners talk together to discuss their thinking. They make…

  19. Climatic Concepts and Regions.

    ERIC Educational Resources Information Center

    Thomas, Paul F.

    Designed for students in grades 7 through 12, this teaching unit presents illustrative resource materials depicting concepts related to climate and geographic regions. Emphasis is on giving students an understanding of climatic elements and factors, not as isolated, disjointed entities, but as a dynamic interplay of forces having a very definite…

  20. Embodying Policy Concepts

    ERIC Educational Resources Information Center

    Evans, John; Davies, Brian

    2012-01-01

    This article introduces some of the key concepts that we have used in our research to help illuminate the multiple and different ways in which apparently ubiquitous health policies relating to obesity, exercise, diet and health are mediated and shaped both globally and nationally, as well as within regional, school and other contexts. The analyses…

  1. Children's Conceptions of Trust.

    ERIC Educational Resources Information Center

    Kahn, Peter H., Jr.; Turiel, Elliot

    Aware that children conceive of different types of trust, a study examined 60 children's conception of trust. The subjects comprised three age groups: 6-7 years old, 8-9 years old, and 10-11 years old. Each subject was interviewed on the basis of three stories. The stories depicted a hypothesized violation of trust in a moral context (lying),…

  2. The Concept of "Teachability."

    ERIC Educational Resources Information Center

    Tubbs, Nigel

    2003-01-01

    Asserts that "teachability" is a speculative concept that has for its form and content the absolute, suggesting that its dialectical movement and speculative significance are mis-recognized when the illusionary nature of its constitutive moments is suppressed. The essay outlines the speculative nature of the master/slave relationship in Hegel's…

  3. Naive Conceptions of Motion.

    ERIC Educational Resources Information Center

    McCloskey, Michael

    Two experiments were conducted to characterize the system of beliefs that make up the naive impetus theory of motion and to determine what effects physics instruction has on students' conceptions of motion. Thirteen college students were asked to solve several quantitative problems and were interviewed about their answers in the first experiment.…

  4. Teaching Weather Concepts.

    ERIC Educational Resources Information Center

    Sebastian, Glenn R.

    Ten exercises based on the weather map provided in the national newspaper "U.S.A. Today" are used to teach intermediate grade students about weather. An overview describes the history of "U.S.A. Today," the format of the newspaper's weather map, and the map's suitability for teaching weather concepts. Specific exercises, which are briefly…

  5. I Teach Concepts.

    ERIC Educational Resources Information Center

    Januszewski, Alan

    This paper describes the author's views on and approach to teaching about educational technology. The author teaches concepts, with an emphasis on "teaching about" rather than "teaching how". The author's educational background and experiences, and their influence on his current views are described. While the definitions of educational technology…

  6. Creativity: Concepts and Explorations.

    ERIC Educational Resources Information Center

    Rookey, T. Jerome

    The lack of a universal definition of creativity has led to the assessment of creativity according to the definition favored by the evaluator. These assessments fall into four groups. The first centers around the concept of the creative product; it assesses a tangible event or relationship that results from the creative process, which is implied…

  7. Teaching Aerobic Fitness Concepts.

    ERIC Educational Resources Information Center

    Sander, Allan N.; Ratliffe, Tom

    2002-01-01

    Discusses how to teach aerobic fitness concepts to elementary students. Some of the K-2 activities include location, size, and purpose of the heart and lungs; the exercise pulse; respiration rate; and activities to measure aerobic endurance. Some of the 3-6 activities include: definition of aerobic endurance; heart disease risk factors;…

  8. Changing Conceptions of Nonprofessionals.

    ERIC Educational Resources Information Center

    Vanek, Linda; Powell, Thomas J.

    The authors distinguish between the therapeutically-oriented and the socializationally-oriented nonprofessionals, and maintain that both are valuable in a comprehensive program and neither one is uniquely effective. Hence, task assignments should represent the differing orientations as should training programs. A realistic conception of the types…

  9. Advanced Concept Modeling

    NASA Technical Reports Server (NTRS)

    Chaput, Armand; Johns, Zachary; Hodges, Todd; Selfridge, Justin; Bevirt, Joeben; Ahuja, Vivek

    2015-01-01

    Advanced Concepts Modeling software validation, analysis, and design. This was a National Institute of Aerospace contract with a lot of pieces. Efforts ranged from software development and validation for structures and aerodynamics, through flight control development, and aeropropulsive analysis, to UAV piloting services.

  10. Some Core Contested Concepts

    ERIC Educational Resources Information Center

    Chomsky, Noam

    2015-01-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and…

  11. Entropy, a Protean Concept

    NASA Astrophysics Data System (ADS)

    Balian, Roger

    We review at a tutorial level the many aspects of the concept of entropy and their interrelations, in thermodynamics, information theory, probability theory and statistical physics. The consideration of relevant entropies and the identification of entropy with missing information enlighten the paradoxes of irreversibility and of Maxwell's demon.

  12. Mass Producing Concept Inventories

    NASA Astrophysics Data System (ADS)

    Garvin-Doxas, K.; Klymkowsky, M.; Doxas, I.

    2005-12-01

    Concept Inventories are research based assessment instruments which derive their validity and reliability from well researched distracters that represent students' dominant misconceptions in the field. They have formed the backbone of research based reform efforts in Physics by providing valid, reliable common assessment instruments with which to evaluate different teaching approaches and materials, and many disciplines are in the process of developing large numbers of Concept Inventories for their own subject areas. Unfortunately, Concept Inventories are labour and time intensive, with instruments taking anywhere from 2-8 years to develop, and correspondingly high price tags. The time and cost is directly related to the fact that valid, reliable instruments require mapping the dominant misconceptions in a field, which is usually a time consuming and labour intensive task. This paper will describe how we use Latent Semantic Analysis (LSA) with unsupervised clustering of the LSA vectors to identify and classify misconceptions in various science disciplines, considerably speeding up the process of misconception discovery and classification. The paper will present results from Astronomy and Biology, and will describe current efforts to develop a Concept Inventory for Space Physics.

  13. Concepts in Environmental Education.

    ERIC Educational Resources Information Center

    Hopkins, Sally

    Presented is a discussion of the components and concepts of an ecology typical of the coastal southeastern United States. Principles presented are applicable to other areas. The discussion includes several major sections: the environment, wildlife management, freshwater ecosystems, and the estuarine environment. Numerous figures and illustrations…

  14. Understanding the Agribusiness Concept.

    ERIC Educational Resources Information Center

    Lee, Jasper S.

    Designed to aid in learning the main ideas of the agribusiness concept, this document answers the following questions, treating each answer in a separate explanatory section: (1) What is the meaning of the terms "agriculture" and "agribusiness"? (2) What is the relationship of agriculture and agribusiness? (3) What is involved in tracing an…

  15. Concept-Based Learning

    ERIC Educational Resources Information Center

    Schill, Bethany; Howell, Linda

    2011-01-01

    A major part of developing concept-based instruction is the use of an overarching idea to provide a conceptual lens through which students view the content of a particular subject. By using a conceptual lens to focus learning, students think at a much deeper level about the content and its facts (Erickson 2007). Therefore, the authors collaborated…

  16. Two Conceptions of Virtue

    ERIC Educational Resources Information Center

    Hill, Thomas E., Jr.

    2013-01-01

    The general questions are: what is virtue and how can it be cultivated? The specific focus is on the conceptions of virtue in the works of Immanuel Kant and John Rawls. Kant regarded virtue as a good will that is also strong enough to resist contrary passions, impulses, and inclinations. Childhood training can prepare children for virtue, but…

  17. Advanced Civilian Aeronautical Concepts

    NASA Technical Reports Server (NTRS)

    Bushnell, Dennis M.

    1996-01-01

    Paper discusses alternatives to currently deployed systems which could provide revolutionary improvements in metrics applicable to civilian aeronautics. Specific missions addressed include subsonic transports, supersonic transports and personal aircraft. These alternative systems and concepts are enabled by recent and envisaged advancements in electronics, communications, computing and Designer Fluid Mechanics in conjunction with a design approach employing extensive synergistic interactions between propulsion, aerodynamics and structures.

  18. Mapping Sociological Concepts.

    ERIC Educational Resources Information Center

    Trepagnier, Barbara

    2002-01-01

    Focuses on the use of cognitive mapping within sociology. Describes an assignment where students created a cognitive map that focused on names of theorists and concepts related to them. Discusses sociological imagination in relation to cognitive mapping and the assessment of the assignment. (CMK)

  19. DSMS science operations concept

    NASA Technical Reports Server (NTRS)

    Connally, M. J.; Kuiper, T. B.

    2001-01-01

    The Deep Space Mission System (DSMS) Science Operations Concept describes the vision for enabling the use of the DSMS, particularly the Deep Space Network (DSN) for direct science observations in the areas of radio astronomy, planetary radar, radio science and VLBI.

  20. Separations innovative concepts: Project summary

    SciTech Connect

    Lee, V.E.

    1988-05-01

    This project summary includes the results of 10 innovations that were funded under the US Department's Innovative Concept Programs. The concepts address innovations that can substantially reduce the energy used in industrial separations. Each paper describes the proposed concept, and discusses the concept's potential energy savings, market applications, technical feasibility, prior work and state of the art, and future development needs.

  1. Concepts in Activities and Discourses

    ERIC Educational Resources Information Center

    Greeno, James G.

    2012-01-01

    The articles in this special issue make valuable contributions toward a scientific understanding of concepts that is broader than the traditional view that has focused on categorizing by individuals. I propose considering concepts for categorization as a special case of concepts. At their clearest, they can be referred to as "formal concepts," or…

  2. Key Concepts in Informatics: Algorithm

    ERIC Educational Resources Information Center

    Szlávi, Péter; Zsakó, László

    2014-01-01

    "The system of key concepts contains the most important key concepts related to the development tasks of knowledge areas and their vertical hierarchy as well as the links of basic key concepts of different knowledge areas." (Vass 2011) One of the most important of these concepts is the algorithm. In everyday life, when learning or…

  3. Trimble Vrs Concept

    NASA Astrophysics Data System (ADS)

    Luttenberger, C.

    Presenting the Trimble Virtual Reference Station (VRS) concept. High accuracy Real-Time Kinematic Positioning with GPS is one of todaySs most widely used surveying techniques. But, its use is restricted by the effects of the iono- sphere and troposphere which create systematic errors in the raw data. In practice, these mean that the distance between a rover (mobile) receiver and its reference sta- tion has to be quite short in order to work efficiently. The concept of Virtual Reference Stations offers a new opportunity. When used, the systematic errors in the reference station data are either reduced, or eliminated. This not only allows a user to increase the distance at which the rover receiver is located from the reference, it also increases the reliability of the system and reduces the OTF initialization time. The presentation describes the setup of a VRS system, as well the used model to reduce the error influence in such a permanente reference station network.

  4. Advanced sulfur control concepts

    SciTech Connect

    Harrison, D.P.; Lopez-Ortiz, A.; White, J.D.; Groves, F.R. Jr.

    1995-11-01

    The primary objective of this study is the direct production of elemental sulfur during the regeneration of high temperature desulfurization sorbents. Three possible regeneration concepts were identified as a result of a literature search. The potential for elemental sulfur production from a number of candidate metal oxide sorbents using each regeneration concept was evaluated on the basis of a thermodynamic analysis. Two candidate sorbents, Fe{sub 2}O{sub 3} and CeO{sub 2} were chosen for experimental testing. The experimental test program using both electrobalance and fixed-bed reactor sis now getting underway. The objective is to determine reaction conditions--temperature, pressure, space velocity, and regeneration feed gas composition--which will maximize the yield of elemental sulfur in the regeneration product gas. Experimental results are to be used to define a conceptual desulfurization-regeneration process and to provide a preliminary economic evaluation.

  5. Free radical propulsion concept

    NASA Technical Reports Server (NTRS)

    Hawkins, C. E.; Nakanishi, S.

    1981-01-01

    A free radical propulsion concept utilizing the recombination energy of dissociated low molecular weight gases to produce thrust was examined. The concept offered promise of a propulsion system operating at a theoretical impulse, with hydrogen, as high as 2200 seconds at high thrust to power ratio, thus filling the gas existing between chemical and electrostatic propulsion capabilities. Microwave energy used to dissociate a continuously flowing gas was transferred to the propellant via three body recombination for conversion to propellant kinetic energy. Power absorption by the microwave plasma discharge was in excess of 90 percent over a broad range of pressures. Gas temperatures inferred from gas dynamic equations showed much higher temperatures from microwave heating than from electrothermal heating. Spectroscopic analysis appeared to corroborate the inferred temperatures of one of the gases tested.

  6. TQM: the essential concepts.

    PubMed

    Chambers, D W

    1998-01-01

    This is an introduction to the major concepts in total quality management, a loose collection of management approaches that focus on continuous improvement of processes, guided by routine data collection and adjustment of the processes. Customer focus and involvement of all members of an organization are also characteristics commonly found in TQM. The seventy-five-year history of the movement is sketched from its beginning in statistical work on quality assurance through the many improvements and redefinitions added by American and Japanese thinkers. Essential concepts covered include: control cycles, focus on the process rather than the defects, the GEAR model, importance of the customer, upstream quality, just-in-time, kaizen, and service quality.

  7. Modular Reflector Concept Study.

    DTIC Science & Technology

    1981-03-01

    capability provides discretionary backup for direct monitoring and troubleshooting. DCMi MODULE, DEPLOYED DCM MODULE CREW COMPARTMENT MAN IPULATOR MANIPULATOR...are equivalent in size, shape, and function to DCM modules. META modules differ from DCMI modules by having three intermediate struts per module...excluding static loading, which will vary according to mission). As with the DCMI concept, META modules are limited in size by the available diameter

  8. Firefly system concept

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.

    1991-01-01

    The 'Firefly' project has developed and implemented an infrared (IR) remote sensing prototype system based on the concept presented. The Firefly system produces images through smoke that will provide near real-time wildland fire information for fire management and suppression. The prototype will be tested through the 1991 fire season. Results of the testing will be incorporated into the final system design for operational use at the end of 1992.

  9. Some core contested concepts.

    PubMed

    Chomsky, Noam

    2015-02-01

    Core concepts of language are highly contested. In some cases this is legitimate: real empirical and conceptual issues arise. In other cases, it seems that controversies are based on misunderstanding. A number of crucial cases are reviewed, and an approach to language is outlined that appears to have strong conceptual and empirical motivation, and to lead to conclusions about a number of significant issues that differ from some conventional beliefs.

  10. Elaborating on threshold concepts

    NASA Astrophysics Data System (ADS)

    Rountree, Janet; Robins, Anthony; Rountree, Nathan

    2013-09-01

    We propose an expanded definition of Threshold Concepts (TCs) that requires the successful acquisition and internalisation not only of knowledge, but also its practical elaboration in the domains of applied strategies and mental models. This richer definition allows us to clarify the relationship between TCs and Fundamental Ideas, and to account for both the important and the problematic characteristics of TCs in terms of the Knowledge/Strategies/Mental Models Framework defined in previous work.

  11. Water laws and concepts

    USGS Publications Warehouse

    Thomas, H.E.

    1970-01-01

    Throughout human history various laws and customs have developed concerning the individual rights and rights in common to the waters of the earth. Many existing laws and concepts are clearly influenced by the environment in which they originated and reflect the relative abundance or scarcity of water. Many concepts reflect the people's original interests in the water and once established have been passed from generation to generation with little modification. Some laws and concepts have been carried by people in their migrations and colonial expansions to vastly different environments, with rather curious consequences. In many places water laws that had been well adapted to the natural environment have become less tenable because of man's activities in modifying that environment, or because of increasing use of water: Increasing consumptive use shifts the water economy toward lesser abundance or increasing deficiency; increasing nonconsumptive use results in pollution of the water resources, so that they become less suitable for other users. The water-rights systems in the United States vary from State to State: some are reasonably fitted to their environment, some have outlived their place in history, some are wasteful of water, some show favoritism to certain special interests or segments of the population. Water-use rights are universally recognized as real property, with constitutional protection against deprivation without due process of law.

  12. Generalizing about Genre: New Conceptions of an Old Concept.

    ERIC Educational Resources Information Center

    Devitt, Amy J.

    1993-01-01

    Explains the new conception of literary genre as it is being devised in the fields of literary studies, linguistics, and rhetoric. Suggests how this new conception has affected the thinking of teachers on writing and writing instruction. (HB)

  13. Space Mission Concept Development Using Concept Maturity Levels

    NASA Technical Reports Server (NTRS)

    Wessen, Randii R.; Borden, Chester; Ziemer, John; Kwok, Johnny

    2013-01-01

    Over the past five years, pre-project formulation experts at the Jet Propulsion Laboratory (JPL) has developed and implemented a method for measuring and communicating the maturity of space mission concepts. Mission concept development teams use this method, and associated tools, prior to concepts entering their Formulation Phases (Phase A/B). The organizing structure is Concept Maturity Level (CML), which is a classification system for characterizing the various levels of a concept's maturity. The key strength of CMLs is the ability to evolve mission concepts guided by an incremental set of assessment needs. The CML definitions have been expanded into a matrix form to identify the breadth and depth of analysis needed for a concept to reach a specific level of maturity. This matrix enables improved assessment and communication by addressing the fundamental dimensions (e.g., science objectives, mission design, technical risk, project organization, cost, export compliance, etc.) associated with mission concept evolution. JPL's collaborative engineering, dedicated concept development, and proposal teams all use these and other CML-appropriate design tools to advance their mission concept designs. This paper focuses on mission concept's early Pre-Phase A represented by CMLs 1- 4. The scope was limited due to the fact that CMLs 5 and 6 are already well defined based on the requirements documented in specific Announcement of Opportunities (AO) and Concept Study Report (CSR) guidelines, respectively, for competitive missions; and by NASA's Procedural Requirements NPR 7120.5E document for Projects in their Formulation Phase.

  14. Self-Concept Is a Concept Worth Considering

    ERIC Educational Resources Information Center

    Shields, Nora

    2009-01-01

    There is a growing recognition of the importance of self-concept in the pediatric rehabilitation research literature. There also is confusion and inconsistency in the definitions of and the terminology used to describe self-concept. What is agreed is that self-concept is multidimensional, comprising a child's perception of their personal…

  15. Children's understanding of additive concepts.

    PubMed

    Robinson, Katherine M; Dubé, Adam K; Beatch, Jacqueline-Ann

    2017-04-01

    Most research on children's arithmetic concepts is based on one concept at a time, limiting the conclusions that can be made about how children's conceptual knowledge of arithmetic develops. This study examined six arithmetic concepts (identity, negation, commutativity, equivalence, inversion, and addition and subtraction associativity) in Grades 3, 4, and 5. Identity (a-0=a) and negation (a-a=0) were well understood, followed by moderate understanding of commutativity (a+b=b+a) and inversion (a+b-b=a), with weak understanding of equivalence (a+b+c=a+[b+c]) and associativity (a+b-c=[b-c]+a). Understanding increased across grade only for commutativity and equivalence. Four clusters were found: The Weak Concept cluster understood only identity and negation; the Two-Term Concept cluster also understood commutativity; the Inversion Concept cluster understood identity, negation, and inversion; and the Strong Concept cluster had the strongest understanding of all of the concepts. Grade 3 students tended to be in the Weak and Inversion Concept clusters, Grade 4 students were equally likely to be in any of the clusters, and Grade 5 students were most likely to be in the Two-Term and Strong Concept clusters. The findings of this study highlight that conclusions about the development of arithmetic concepts are highly dependent on which concepts are being assessed and underscore the need for multiple concepts to be investigated at the same time.

  16. RADAR "SAIL" satellite concept

    NASA Astrophysics Data System (ADS)

    Aguttes, Jean Paul; Sombrin, Jacques; Conde, Eric

    1996-11-01

    The Radar SAIL concept is based on the use of a rectangular antenna lying in the dawn-dusk orbital plane with the length (along speed vector) smaller than the height. Such geometry makes it possible to place the solar cells on the back of the antenna, to use gravity gradient stabilisation, and to implement multipath-free GPS interferometric measurement of the antenna deformation thus allowing structural relaxation. Less obviously, the geometry favours the RADAR design too, by allowing grating lobes and therefore a lower density of built-in electronic in the active antenna. The antenna can be thin and packed for launch inside a cylinder-shaped bus having pyrotechnic doors for the antenna deployement and bearing the rest of the payload and the service equipment. With respect to a standard design of performant missions, cost savings come from the bus, whose functions (AOCS, power supply) are simplified, from the launch since the mass budget and the stowing configuration become compatible with medium size rockets (LLV2/3, DELTA-LITE, LM-4.), and from the active antenna built-in electronics. The RADAR SAIL concept is all the more cost effective when the mission requires a large, high and short antenna, i.e. high resolution (<5m), low frequency band (L or S or even P), high revisiting, multiple frequencies. Mission implementation and funding can be favored by the new capability to share the satellite between autonomous regional operators. Combined with ground DBF (digital beam forming) technique, the concept allows extremely simple and low cost missions providing a fixed wide swath (10 to 15 m resolution within 500km to 1000 km swath) for systematic surveillance or monitoring.

  17. GLAST Mission Concept Study

    NASA Technical Reports Server (NTRS)

    Cominsky, Lynn R.

    2001-01-01

    Cominsky served as the chair of the GLAST Public Affairs Working Group during the mission concept study. The major accomplishments of this group, which were carried out under her direction include: (1) GLAST Outreach website; (2) Brochure for scientists; (3) Brochure for public; (4) Developed the five key science goal 'bullets' to explain GLAST to the public, as well as the motto used on the GLAST brochures 'Quest for the Ultimate Sources of Energy in the Universe'; (5) Defined the EPO program for GLAST for the proposal phase. Developed initial program outline and budget; and (6) Assisted in the development of the GLAST exhibit, which was used at several scientific conferences.

  18. On the gestalt concept.

    PubMed

    Breidbach, Olaf; Jost, Jürgen

    2006-08-01

    We define a gestalt as the invariants of a collection of patterns that can mutually be transformed into each other through a class of transformations encoded by, or conversely, determining that gestalt. The class of these transformations needs to satisfy structural regularities like the ones of the mathematical structure of a group. This makes an analysis of a gestalt possible in terms of relations between its representing patterns. While the gestalt concept has its origins in cognitive psychology, it has also important implications for morphology.

  19. The concept behind sugammadex.

    PubMed

    Epemolu, O; Bom, A

    2014-05-01

    Sugammadex is the first selective relaxant binding agent. It allows rapid reversal of any degree of neuromuscular blockade induced by steroidal neuromuscular blocking agents. Sugammadex acts by encapsulation of the neuromuscular blocking agent. This prevents the drug from acting on prejunctional and postjunctional nicotinic receptors, allowing acetylcholine to activate these receptors, and resulting in reversal of the neuromuscular blockade. Objective monitoring of the degree of neuromuscular blockade is strongly recommended to determine the optimal dose of sugammadex. A good understanding of the concept behind sugammadex is essential in order to use this reversal agent in clinical practice.

  20. Indian concepts on sexuality

    PubMed Central

    Chakraborty, Kaustav; Thakurata, Rajarshi Guha

    2013-01-01

    India is a vast country depicting wide social, cultural and sexual variations. Indian concept of sexuality has evolved over time and has been immensely influenced by various rulers and religions. Indian sexuality is manifested in our attire, behavior, recreation, literature, sculptures, scriptures, religion and sports. It has influenced the way we perceive our health, disease and device remedies for the same. In modern era, with rapid globalization the unique Indian sexuality is getting diffused. The time has come to rediscover ourselves in terms of sexuality to attain individual freedom and to reinvest our energy to social issues related to sexuality. PMID:23858263

  1. Mars rover 1988 concepts

    NASA Technical Reports Server (NTRS)

    Pivirotto, Donna Shirley; Penn, Thomas J.; Dias, William C.

    1989-01-01

    Results of FY88 studies of a sample-collecting Mars rover are presented. A variety of rover concepts are discussed which include different technical approaches to rover functions. The performance of rovers with different levels of automation is described and compared to the science requirement for 20 to 40 km to be traversed on the Martian surface and for 100 rock and soil samples to be collected. The analysis shows that a considerable amount of automation in roving and sampling is required to meet this requirement. Additional performance evaluation shows that advanced RTG's producing 500 W and 350 WHr of battery storage are needed to supply the rover.

  2. Open airscrew VTOL concepts

    NASA Technical Reports Server (NTRS)

    Stepniewski, W. Z.; Tarczynski, T.

    1992-01-01

    The following concepts, based on using open airscrew(s) for VTOL maneuvers, are re-examined in light of current technology: (1) tip-driven helicopters, (2) compound helicopters; and (3) high-speed VTOL aircraft, represented by tiltrotors, tiltwings, retractoplanes and stoppable rotors. Criteria, permitting one to compare performance of aircraft using diverse lifting and propelling methods are established. Determination of currently possible performance, indication of near-future potentials, and comparison of those items with the baseline levels (as represented by contemporary shaft-driven helicopters, first generation tiltrotors, and commercial turboprop fixed-wind aircraft) constitutes bulk of this report.

  3. Preparing the DSN operations concepts

    NASA Technical Reports Server (NTRS)

    Salazar, A. J.; Bailey, M. D.; Kuo, N. R.; Wilkinson, B. M.

    1993-01-01

    Operations concepts are prepared to support a specific application and can, therefore, be classified accordingly. Studies of NASA and military operations concepts suggest three major types: data services, customer services, and systems oriented. Data services concepts concentrate on data types (e.g., telemetry and command) and how these data are processed and delivered to the user. Such concepts are normally used by data-processing centers to describe data-coding schemes and data formats. Customer services concepts concentrate on the customers' requirements and describe how these requirements are met using the systems available to the operation. Project centers use such concepts to describe the various types of data as they flow from the source (e.g., a spacecraft) to the end user (i.e., the customer). Systems oriented concepts concentrate on the use of systems for processing and delivering customer data. This paper examines the latter type and the 'concepts' that are inherent within them.

  4. Let's Teach Life Insurance Concepts

    ERIC Educational Resources Information Center

    Coleman, Larry D.

    1973-01-01

    The author presents arguments for teaching life insurance concepts as part of the business education curriculum. He also presents specific facts, "knowledges," understandings, and concepts as part of the learning process. (AG)

  5. Advanced microwave processing concepts

    SciTech Connect

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.

    1995-05-01

    The purpose of this work is to explore the feasibility of several advanced microwave processing concepts to develop new energy-efficient materials and processes. The project includes two tasks: (1) commercialization of the variable-frequency microwave furnace; and (2) microwave curing of polymer composites. The variable frequency microwave furnace, whose initial conception and design was funded by the AIC Materials Program, will allow us, for the first time, to conduct microwave processing studies over a wide frequency range. This novel design uses a high-power traveling wave tube (TWT) originally developed for electronic warfare. By using this microwave source, one can not only select individual microwave frequencies for particular experiments, but also achieve uniform power densities over a large area by the superposition of many different frequencies. Microwave curing of thermoset resins will be studied because it hold the potential of in-situ curing of continuous-fiber composites for strong, lightweight components. Microwave heating can shorten curing times, provided issues of scaleup, uniformity, and thermal management can be adequately addressed.

  6. Rocketdyne RBCC Concept Development

    NASA Technical Reports Server (NTRS)

    Ortwerth, P.; Ratekin, G.; Goldman, A.; Emanuel, M.; Brown, C.; Ketchum, A.; Horn, M.

    1997-01-01

    Rocketdyne is pursuing the conceptual design and development of a Rocket Based Combined Cycle (BBCC) engine for booster and SSTO, advanced reusable space transportation systems under the Advanced Reusable Transportation Technologies contract with NASA Marshall Space Flight Center. The Rocketdyne concept is a fixed geometry integrated rocket, ramjet, scramjet which is hydrogen fueled and uses hydrogen regenerative cooling. Vision vehicle integration studies have determined that scramjet operation to the range of Mach 10 to 12 has high payoff for low cost reusable space transportation. Rocketdyne is internally developing versions of the concept for other applications in high speed aircraft and missiles with hydrocarbon fuel systems. A subscale engine ground test program is underway for all modes of operation from takeoff to Mach 8. High altitude rocket tests will only be completed as part of the ground test program to validate high expansion ratio performance. A unique feature of the ground test series is the inclusion of dynamic trajectory simulation with real time Mach number, altitude, engine throttling, and RBCC mode changes in a specially modified freejet test facility at GASL. Preliminary cold flow air augmented rocket and all rocket test results have met program goals and have been used to integrate all modes of operation in a single combustor design with a fixed geometry inlet for design confirmation tests. A water cooled subscale engine is currently being fabricated for test during the early part of 1998.

  7. Advanced microwave processing concepts

    SciTech Connect

    Lauf, R.J.; McMillan, A.D.; Paulauskas, F.L.

    1997-04-01

    The purpose of this work is to explore the feasibility of several advanced microwave processing concepts to develop new energy-efficient materials and processes. The project includes two tasks: (1) commercialization of the variable-frequency microwave furnace; and (2) microwave curing of polymeric materials. The variable frequency microwave furnace, whose initial conception and design was funded by the AIM Materials Program, allows the authors, for the first time, to conduct microwave processing studies over a wide frequency range. This novel design uses a high-power traveling wave tube (TWT) originally developed for electronic warfare. By using this microwave source, one can not only select individual microwave frequencies for particular experiments, but also achieve uniform power densities over a large area by the superposition of many different frequencies. Microwave curing of various thermoset resins will be studied because it holds the potential of in-situ curing of continuous-fiber composites for strong, lightweight components or in-situ curing of adhesives, including metal-to-metal. Microwave heating can shorten curing times, provided issues of scaleup, uniformity, and thermal management can be adequately addressed.

  8. ATR performance modeling concepts

    NASA Astrophysics Data System (ADS)

    Ross, Timothy D.; Baker, Hyatt B.; Nolan, Adam R.; McGinnis, Ryan E.; Paulson, Christopher R.

    2016-05-01

    Performance models are needed for automatic target recognition (ATR) development and use. ATRs consume sensor data and produce decisions about the scene observed. ATR performance models (APMs) on the other hand consume operating conditions (OCs) and produce probabilities about what the ATR will produce. APMs are needed for many modeling roles of many kinds of ATRs (each with different sensing modality and exploitation functionality combinations); moreover, there are different approaches to constructing the APMs. Therefore, although many APMs have been developed, there is rarely one that fits a particular need. Clarified APM concepts may allow us to recognize new uses of existing APMs and identify new APM technologies and components that better support coverage of the needed APMs. The concepts begin with thinking of ATRs as mapping OCs of the real scene (including the sensor data) to reports. An APM is then a mapping from explicit quantized OCs (represented with less resolution than the real OCs) and latent OC distributions to report distributions. The roles of APMs can be distinguished by the explicit OCs they consume. APMs used in simulations consume the true state that the ATR is attempting to report. APMs used online with the exploitation consume the sensor signal and derivatives, such as match scores. APMs used in sensor management consume neither of those, but estimate performance from other OCs. This paper will summarize the major building blocks for APMs, including knowledge sources, OC models, look-up tables, analytical and learned mappings, and tools for signal synthesis and exploitation.

  9. AXTAR: Mission Design Concept

    NASA Technical Reports Server (NTRS)

    Ray, Paul S.; Chakrabarty, Deepto; Wilson-Hodge, Colleen A.; Philips, Bernard F.; Remillard, Ronald A.; Levine, Alan M.; Wood, Kent S.; Wolff, Michael T.; Gwon, Chul S.; Strohmayer, Tod E.; Briggs, Michael S.; Capizzo, Peter; Fabisinski, Leo; Hopkins, Randall C.; Hornsby, Linda S.; Johnson, Les; Maples, C. Dauphne; Miernik, Janie H.; Thomas, Dan; DeGeronimo, Gianluigi

    2010-01-01

    The Advanced X-ray Timing Array (AXTAR) is a mission concept for X-ray timing of compact objects that combines very large collecting area, broadband spectral coverage, high time resolution, highly flexible scheduling, and an ability to respond promptly to time-critical targets of opportunity. It is optimized for sub-millisecond timing of bright Galactic X-ray sources in order to study phenomena at the natural time scales of neutron star surfaces and black hole event horizons, thus probing the physics of ultra-dense matter, strongly curved spacetimes, and intense magnetic fields. AXTAR s main instrument, the Large Area Timing Array (LATA) is a collimated instrument with 2 50 keV coverage and over 3 square meters effective area. The LATA is made up of an array of super-modules that house 2-mm thick silicon pixel detectors. AXTAR will provide a significant improvement in effective area (a factor of 7 at 4 keV and a factor of 36 at 30 keV) over the RXTE PCA. AXTAR will also carry a sensitive Sky Monitor (SM) that acts as a trigger for pointed observations of X-ray transients in addition to providing high duty cycle monitoring of the X-ray sky. We review the science goals and technical concept for AXTAR and present results from a preliminary mission design study

  10. Modular reflector concept study

    NASA Technical Reports Server (NTRS)

    Vaughan, D. H.

    1981-01-01

    A study was conducted to evaluate the feasibility of space erecting a 100 meter paraboloidal radio frequency reflector by joining a number of individually deployed structural modules. Three module design concepts were considered: (1) the deployable cell module (DCM); (2) the modular paraboloidal erectable truss antenna (Mod-PETA); and (3) the modular erectable truss antenna (META). With the space shuttle (STS) as the launch system, the methodology of packaging and stowing in the orbiter, and of dispensing, deploying and joining, in orbit, were studied and the necessary support equipment identified. The structural performance of the completed reflectors was evaluated and their overall operational capability and feasibility were evaluated and compared. The potential of the three concepts to maintain stable shape in the space environment was determined. Their ability to operate at radio frequencies of 1 GHz and higher was assessed assuming the reflector surface to consist of a number of flat, hexagonal facets. A parametric study was performed to determine figure degradation as a function of reflector size, flat facet size, and f/D ratio.

  11. PRSEUS Structural Concept Development

    NASA Technical Reports Server (NTRS)

    Velicki, Alex; Jegley, Dawn

    2014-01-01

    A lighter, more robust airframe is one of the key technological advancements necessary for the successful launch of any large next-generation transport aircraft. Such a premise dictates that considerable improvements beyond current state-of-the-art aluminum structures is needed, and that improvements of this magnitude will require an extensive use of composite materials that are not only lightweight, but also economical to produce. To address this challenge, researchers at NASA and The Boeing Company are developing a novel structural concept called the Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) under the Environmentally Responsible Aviation (ERA) Project. It is an integrally stiffened panel concept that is stitched together and designed to maintain residual load-carrying capabilities under a variety of damage scenarios. In addition to improved structural performance, an important facet of this unique arrangement of stitched carbon fibers is its innovative manufacturing method that has the potential to lower fabrication costs by eliminating fasteners and autoclave cures. The rationale and development status for this new approach forms the basis of the work described in this paper. The test specimens described herein were fabricated, or are currently being fabricated, by The Boeing Company, while the structural analyses and testing tasks are being performed by NASA and Boeing personnel.

  12. Online Exhibits & Concept Maps

    NASA Astrophysics Data System (ADS)

    Douma, M.

    2009-12-01

    Presenting the complexity of geosciences to the public via the Internet poses a number of challenges. For example, utilizing various - and sometimes redundant - Web 2.0 tools can quickly devour limited time. Do you tweet? Do you write press releases? Do you create an exhibit or concept map? The presentation will provide participants with a context for utilizing Web 2.0 tools by briefly highlighting methods of online scientific communication across several dimensions. It will address issues of: * breadth and depth (e.g. from narrow topics to well-rounded views), * presentation methods (e.g. from text to multimedia, from momentary to enduring), * sources and audiences (e.g. for experts or for the public, content developed by producers to that developed by users), * content display (e.g. from linear to non-linear, from instructive to entertaining), * barriers to entry (e.g. from an incumbent advantage to neophyte accessible, from amateur to professional), * cost and reach (e.g. from cheap to expensive), and * impact (e.g. the amount learned, from anonymity to brand awareness). Against this backdrop, the presentation will provide an overview of two methods of online information dissemination, exhibits and concept maps, using the WebExhibits online museum (www.webexhibits.org) and SpicyNodes information visualization tool (www.spicynodes.org) as examples, with tips on how geoscientists can use either to communicate their science. Richly interactive online exhibits can serve to engage a large audience, appeal to visitors with multiple learning styles, prompt exploration and discovery, and present a topic’s breadth and depth. WebExhibits, which was among the first online museums, delivers interactive information, virtual experiments, and hands-on activities to the public. While large, multidisciplinary exhibits on topics like “Color Vision and Art” or “Calendars Through the Ages” require teams of scholars, user interface experts, professional writers and editors

  13. Can We Feel Physics Concepts?

    ERIC Educational Resources Information Center

    Su, Yucheng

    2010-01-01

    There are many ways to improve students' understanding of physics concepts. This article focused on drawing students' attention with picture-embedded questions. Pictures give students a direct impression or feeling about the corresponding concepts, which really makes a difference. However, the effects are limited. Some physics concepts are…

  14. The Concept of Philosophical Education

    ERIC Educational Resources Information Center

    Boyum, Steinar

    2010-01-01

    Strangely, the concept of philosophical education is not much in use, at least not as a "philosophical" concept. In this essay, Steinar Boyum attempts to outline such a philosophical concept of philosophical education. Boyum uses Plato's Allegory of the Cave, Rene Descartes's life of doubt, and Immanuel Kant's criticism of metaphysics as paradigms…

  15. Teachers' Conceptions of Tangent Line

    ERIC Educational Resources Information Center

    Paez Murillo, Rosa Elvira; Vivier, Laurent

    2013-01-01

    In order to study the conceptions, and their evolutions, of the tangent line to a curve an updating workshop which took place in Mexico was designed for upper secondary school teachers. This workshop was planned using the methodology of cooperative learning, scientific debate and auto reflection (ACODESA) and the conception-knowing-concept model…

  16. Concepts of Chinese Folk Happiness

    ERIC Educational Resources Information Center

    Ip, Po Keung

    2011-01-01

    Discourses on Chinese folk happiness are often based on anecdotal narratives or qualitative analysis. Two traditional concepts of happiness popular in Chinese culture are introduced. The paper constructs a concept of Chinese folk happiness on basis of the findings of a scientific survey on the Taiwanese people regarding their concepts of…

  17. Concept Learning through Image Processing.

    ERIC Educational Resources Information Center

    Cifuentes, Lauren; Yi-Chuan, Jane Hsieh

    This study explored computer-based image processing as a study strategy for middle school students' science concept learning. Specifically, the research examined the effects of computer graphics generation on science concept learning and the impact of using computer graphics to show interrelationships among concepts during study time. The 87…

  18. Nonstandard Student Conceptions about Infinitesimals

    ERIC Educational Resources Information Center

    Ely, Robert

    2010-01-01

    This is a case study of an undergraduate calculus student's nonstandard conceptions of the real number line. Interviews with the student reveal robust conceptions of the real number line that include infinitesimal and infinite quantities and distances. Similarities between these conceptions and those of G. W. Leibniz are discussed and illuminated…

  19. On the Nature of Concepts.

    ERIC Educational Resources Information Center

    Ninnes, L. E.

    It is difficult to give a precise meaning to the term "concept" because to specify any sense to the term is already to be using concepts. It is impossible to talk about concepts without at the same time having made epistemological and metaphysical commitments. If the epistemological and metaphysical commitments are inadequate, then the…

  20. The Lexicography of Scholarly Concepts.

    ERIC Educational Resources Information Center

    McInnis, Raymond G.

    1995-01-01

    Discusses the function of concepts in scholarly discourse. Topics include the genesis of Greenwood Press's concept dictionaries; the origins of modern rhetoric; the prescriptive nature of meaning in scholarly discourse; conceptual change, including logical positivism, introspection, and historicism; and interdisciplinary application of concepts.…

  1. Practical review of pharmacology concepts.

    PubMed

    Janda, Sue M; Fagan, Nancy L

    2010-01-01

    Pharmacology concepts are used routinely in nursing practice. These concepts may be as simple as drug names and side effects, or as complex as pharmacokinetics or pharmacodynamics. All play major roles in drug efficacy and safety. A practical review of pharmacology, including pharmacokinetic and pharmacodynamic concepts, will be presented.

  2. Football injuries: current concepts.

    PubMed

    Olson, David E; Sikka, Robby Singh; Hamilton, Abigail; Krohn, Austin

    2011-01-01

    Football is one of the most popular sports in the United States and is the leading cause of sports-related injury. A large focus in recent years has been on concussions, sudden cardiac death, and heat illness, all thought to be largely preventable health issues in the young athlete. Injury prevention through better understanding of injury mechanisms, education, proper equipment, and practice techniques and preseason screening may aid in reducing the number of injuries. Proper management of on-field injuries and health emergencies can reduce the morbidity associated with these injuries and may lead to faster return to play and reduced risk of future injury. This article reviews current concepts surrounding frequently seen football-related injuries.

  3. The Saturn management concept

    NASA Technical Reports Server (NTRS)

    Bilstein, R. E.

    1974-01-01

    Management of the Saturn launch vehicles was an evolutionary process, requiring constant interaction between NASA Headquarters, the Marshall Space Flight Center (particularly the Saturn 5 Program Office), and the various prime contractors. Successful Saturn management was a blend of the decades of experience of the von Braun team, management concepts from the Army, Navy, Air Force, and Government, and private industry. The Saturn 5 Program Office shared a unique relationship with the Apollo Program Office at NASA Headquarters. Much of the success of the Saturn 5 Program Office was based on its painstaking attention to detail, emphasis on individual responsibilities (backed up by comprehensive program element plans and management matrices), and a high degree of visibility as embodied in the Program Control Center.

  4. Avicenna's concept of pain.

    PubMed

    Tashani, Osama A; Johnson, Mark I

    2010-09-08

    Ibn Sina (Latin name - Avicenna, 980-1037) is a famous Muslim physician who wrote The Canon of Medicine. Pain-related writings within The Canon were identified and analysed and compared to Galen and Modern Pain Theory. We found evidence in The Canon that Avicenna challenged Galen's concept of pain. Galen insisted that injuries (breach of continuity) were the only cause of pain. In contrast, Avicenna suggested that the true cause of pain was a change of the physical condition (temperament change) of the organ whether there was an injury present or not. Avicenna extended Galen's descriptions of 4 to 15 types of pain and used a terminology that is remarkably similar to that used in the McGill Pain Questionnaire.

  5. Introducing the CTA concept

    NASA Astrophysics Data System (ADS)

    Acharya, B. S.; Actis, M.; Aghajani, T.; Agnetta, G.; Aguilar, J.; Aharonian, F.; Ajello, M.; Akhperjanian, A.; Alcubierre, M.; Aleksić, J.; Alfaro, R.; Aliu, E.; Allafort, A. J.; Allan, D.; Allekotte, I.; Amato, E.; Anderson, J.; Angüner, E. O.; Antonelli, L. A.; Antoranz, P.; Aravantinos, A.; Arlen, T.; Armstrong, T.; Arnaldi, H.; Arrabito, L.; Asano, K.; Ashton, T.; Asorey, H. G.; Awane, Y.; Baba, H.; Babic, A.; Baby, N.; Bähr, J.; Bais, A.; Baixeras, C.; Bajtlik, S.; Balbo, M.; Balis, D.; Balkowski, C.; Bamba, A.; Bandiera, R.; Barber, A.; Barbier, C.; Barceló, M.; Barnacka, A.; Barnstedt, J.; Barres de Almeida, U.; Barrio, J. A.; Basili, A.; Basso, S.; Bastieri, D.; Bauer, C.; Baushev, A.; Becerra, J.; Becherini, Y.; Bechtol, K. C.; Becker Tjus, J.; Beckmann, V.; Bednarek, W.; Behera, B.; Belluso, M.; Benbow, W.; Berdugo, J.; Berger, K.; Bernard, F.; Bernardino, T.; Bernlöhr, K.; Bhat, N.; Bhattacharyya, S.; Bigongiari, C.; Biland, A.; Billotta, S.; Bird, T.; Birsin, E.; Bissaldi, E.; Biteau, J.; Bitossi, M.; Blake, S.; Blanch Bigas, O.; Blasi, P.; Bobkov, A.; Boccone, V.; Boettcher, M.; Bogacz, L.; Bogart, J.; Bogdan, M.; Boisson, C.; Boix Gargallo, J.; Bolmont, J.; Bonanno, G.; Bonardi, A.; Bonev, T.; Bonifacio, P.; Bonnoli, G.; Bordas, P.; Borgland, A.; Borkowski, J.; Bose, R.; Botner, O.; Bottani, A.; Bouchet, L.; Bourgeat, M.; Boutonnet, C.; Bouvier, A.; Brau-Nogué, S.; Braun, I.; Bretz, T.; Briggs, M.; Bringmann, T.; Brook, P.; Brun, P.; Brunetti, L.; Buanes, T.; Buckley, J.; Buehler, R.; Bugaev, V.; Bulgarelli, A.; Bulik, T.; Busetto, G.; Buson, S.; Byrum, K.; Cailles, M.; Cameron, R.; Camprecios, J.; Canestrari, R.; Cantu, S.; Capalbi, M.; Caraveo, P.; Carmona, E.; Carosi, A.; Carr, J.; Carton, P.-H.; Casanova, S.; Casiraghi, M.; Catalano, O.; Cavazzani, S.; Cazaux, S.; Cerruti, M.; Chabanne, E.; Chadwick, P.; Champion, C.; Chen, A.; Chiang, J.; Chiappetti, L.; Chikawa, M.; Chitnis, V. R.; Chollet, F.; Chudoba, J.; Cieślar, M.; Cillis, A.; Cohen-Tanugi, J.; Colafrancesco, S.; Colin, P.; Colome, J.; Colonges, S.; Compin, M.; Conconi, P.; Conforti, V.; Connaughton, V.; Conrad, J.; Contreras, J. L.; Coppi, P.; Corona, P.; Corti, D.; Cortina, J.; Cossio, L.; Costantini, H.; Cotter, G.; Courty, B.; Couturier, S.; Covino, S.; Crimi, G.; Criswell, S. J.; Croston, J.; Cusumano, G.; Dafonseca, M.; Dale, O.; Daniel, M.; Darling, J.; Davids, I.; Dazzi, F.; De Angelis, A.; De Caprio, V.; De Frondat, F.; de Gouveia Dal Pino, E. M.; de la Calle, I.; De La Vega, G. A.; de los Reyes Lopez, R.; De Lotto, B.; De Luca, A.; de Mello Neto, J. R. T.; de Naurois, M.; de Oliveira, Y.; de Oña Wilhelmi, E.; de Souza, V.; Decerprit, G.; Decock, G.; Deil, C.; Delagnes, E.; Deleglise, G.; Delgado, C.; Della Volpe, D.; Demange, P.; Depaola, G.; Dettlaff, A.; Di Paola, A.; Di Pierro, F.; Díaz, C.; Dick, J.; Dickherber, R.; Dickinson, H.; Diez-Blanco, V.; Digel, S.; Dimitrov, D.; Disset, G.; Djannati-Ataï, A.; Doert, M.; Dohmke, M.; Domainko, W.; Dominis Prester, D.; Donat, A.; Dorner, D.; Doro, M.; Dournaux, J.-L.; Drake, G.; Dravins, D.; Drury, L.; Dubois, F.; Dubois, R.; Dubus, G.; Dufour, C.; Dumas, D.; Dumm, J.; Durand, D.; Dyks, J.; Dyrda, M.; Ebr, J.; Edy, E.; Egberts, K.; Eger, P.; Einecke, S.; Eleftheriadis, C.; Elles, S.; Emmanoulopoulos, D.; Engelhaupt, D.; Enomoto, R.; Ernenwein, J.-P.; Errando, M.; Etchegoyen, A.; Evans, P.; Falcone, A.; Fantinel, D.; Farakos, K.; Farnier, C.; Fasola, G.; Favill, B.; Fede, E.; Federici, S.; Fegan, S.; Feinstein, F.; Ferenc, D.; Ferrando, P.; Fesquet, M.; Fiasson, A.; Fillin-Martino, E.; Fink, D.; Finley, C.; Finley, J. P.; Fiorini, M.; Firpo Curcoll, R.; Flores, H.; Florin, D.; Focke, W.; Föhr, C.; Fokitis, E.; Font, L.; Fontaine, G.; Fornasa, M.; Förster, A.; Fortson, L.; Fouque, N.; Franckowiak, A.; Fransson, C.; Fraser, G.; Frei, R.; Albuquerque, I. F. M.; Fresnillo, L.; Fruck, C.; Fujita, Y.; Fukazawa, Y.; Fukui, Y.; Funk, S.; Gäbele, W.; Gabici, S.; Gabriele, R.; Gadola, A.; Galante, N.; Gall, D.; Gallant, Y.; Gámez-García, J.; García, B.; Garcia López, R.; Gardiol, D.; Garrido, D.; Garrido, L.; Gascon, D.; Gaug, M.; Gaweda, J.; Gebremedhin, L.; Geffroy, N.; Gerard, L.; Ghedina, A.; Ghigo, M.; Giannakaki, E.; Gianotti, F.; Giarrusso, S.; Giavitto, G.; Giebels, B.; Gika, V.; Giommi, P.; Girard, N.; Giro, E.; Giuliani, A.; Glanzman, T.; Glicenstein, J.-F.; Godinovic, N.; Golev, V.; Gomez Berisso, M.; Gómez-Ortega, J.; Gonzalez, M. M.; González, A.; González, F.; González Muñoz, A.; Gothe, K. S.; Gougerot, M.; Graciani, R.; Grandi, P.; Grañena, F.; Granot, J.; Grasseau, G.; Gredig, R.; Green, A.; Greenshaw, T.; Grégoire, T.; Grimm, O.; Grube, J.; Grudzinska, M.; Gruev, V.; Grünewald, S.; Grygorczuk, J.; Guarino, V.; Gunji, S.; Gyuk, G.; Hadasch, D.

    2013-03-01

    The Cherenkov Telescope Array (CTA) is a new observatory for very high-energy (VHE) gamma rays. CTA has ambitions science goals, for which it is necessary to achieve full-sky coverage, to improve the sensitivity by about an order of magnitude, to span about four decades of energy, from a few tens of GeV to above 100 TeV with enhanced angular and energy resolutions over existing VHE gamma-ray observatories. An international collaboration has formed with more than 1000 members from 27 countries in Europe, Asia, Africa and North and South America. In 2010 the CTA Consortium completed a Design Study and started a three-year Preparatory Phase which leads to production readiness of CTA in 2014. In this paper we introduce the science goals and the concept of CTA, and provide an overview of the project.

  6. Bioreactor design concepts

    NASA Technical Reports Server (NTRS)

    Bowie, William

    1987-01-01

    Two parallel lines of work are underway in the bioreactor laboratory. One of the efforts is devoted to the continued development and utilization of a laboratory research system. That system's design is intended to be fluid and dynamic. The sole purpose of such a device is to allow testing and development of equipment concepts and procedures. Some of the results of those processes are discussed. A second effort is designed to produce a flight-like bioreactor contained in a double middeck locker. The result of that effort has been to freeze a particular bioreactor design in order to allow fabrication of the custom parts. The system is expected to be ready for flight in early 1988. However, continued use of the laboratory system will lead to improvements in the space bioreactor. Those improvements can only be integrated after the initial flight series.

  7. The evolving microlesion concept

    NASA Astrophysics Data System (ADS)

    Todd, Paul

    The ``microlesion concept'', introduced by D. Grahn in the 1970's, was further explored using published quantitative carcinogenesis data. Laboratory experiments performed by T.C.H. Yang and co-workers and by R.J.M. Fry and co-workers using the Fe ion beam of the Lawrence Berkeley Laboratory Bevalac have resulted in quantitative data on in vitro and in vivo (respectively) carcinogenesis in mouse systems. These data sets were interpreted on the basis of track calculations, and it was found that the action cross section for tumor induction in cultured cells is approximately 0.032 μm2 and that it is about 1/1000th as great in mouse Harderian gland cells. This great difference in carcinogenic sensitivity is a reflection of the biological differences between these two highly promoted systems, neither of which may be quantitatively applicable to humans in space.

  8. The Moon Village Concept

    NASA Astrophysics Data System (ADS)

    Messina, Piero; Foing, Bernard H.; Hufenbach, Bernhard; Haignere, Claudie; Schrogl, Kai-Uwe

    2016-07-01

    The "Moon Village" concept Space exploration is anchored in the International Space Station and in the current and future automatic and planetary automatic and robotic missions that pave the way for future long-term exploration objectives. The Moon represents a prime choice for scientific, operational and programmatic reasons and could be the enterprise that federates all interested Nations. On these considerations ESA is currently elaborating the concept of a Moon Village as an ensemble where multiple users can carry out multiple activities. The Moon Village has the ambition to serve a number of objectives that have proven to be of interest (including astronomy, fundamental research, resources management, moon science, etc. ) to the space community and should be the catalyst of new alliances between public and private entities including non-space industries. Additionally the Moon Village should provide a strong inspirational and education tool for the younger generations . The Moon Village will rely both on automatic, robotic and human-tendered structures to achieve sustainable moon surface operations serving multiple purposes on an open-architecture basis. This Europe-inspired initiative should rally all communities (across scientific disciplines, nations, industries) and make it to the top of the political agendas as a the scientific and technological undertaking but also political and inspirational endeavour of the XXI century. The current reflections are of course based on the current activities and plans on board the ISS and the discussion held in international fora such as the ISECG. The paper will present the status of these reflections, also in view of the ESA Council at Ministerial Level 2016, and will give an overview of the on-going activities being carried out to enable the vision of a Moon Village.

  9. Reactivity control assembly for nuclear reactor. [LMFBR

    DOEpatents

    Bollinger, L.R.

    1982-03-17

    This invention, which resulted from a contact with the United States Department of Energy, relates to a control mechanism for a nuclear reactor and, more particularly, to an assembly for selectively shifting different numbers of reactivity modifying rods into and out of the core of a nuclear reactor. It has been proposed heretofore to control the reactivity of a breeder reactor by varying the depth of insertion of control rods (e.g., rods containing a fertile material such as ThO/sub 2/) in the core of the reactor, thereby varying the amount of neutron-thermalizing coolant and the amount of neutron-capturing material in the core. This invention relates to a mechanism which can advantageously be used in this type of reactor control system.

  10. Some remaining problems in HCDA analysis. [LMFBR

    SciTech Connect

    Chang, Y.W.

    1981-01-01

    The safety assessment and licensing of liquid-metal fast breeder reactors (LMFBRs) requires an analysis on the capability of the reactor primary system to sustain the consequences of a hypothetical core-disruptive accident (HCDA). Although computational methods and computer programs developed for HCDA analyses can predict reasonably well the response of the primary containment system, and follow up the phenomena of HCDA from the start of excursion to the time of dynamic equilibrium in the system, there remain areas in the HCDA analysis that merit further analytical and experimental studies. These are the analysis of fluid impact on reactor cover, three-dimensional analysis, the treatment of the perforated plates, material properties under high strain rates and under high temperatures, the treatment of multifield flows, and the treatment of prestressed concrete reactor vessels. The purpose of this paper is to discuss the structural mechanics of HCDA analysis in these areas where improvements are needed.

  11. Apparatus for controlling molten core debris. [LMFBR

    DOEpatents

    Golden, M.P.; Tilbrook, R.W.; Heylmun, N.F.

    1977-07-19

    Disclosed is an apparatus for containing, cooling, diluting, dispersing and maintaining subcritical the molten core debris assumed to melt through the bottom of a nuclear reactor pressure vessel in the unlikely event of a core meltdown. The apparatus is basically a sacrificial bed system which includes an inverted conical funnel, a core debris receptacle including a spherical dome, a spherically layered bed of primarily magnesia bricks, a cooling system of zig-zag piping in graphite blocks about and below the bed and a cylindrical liner surrounding the graphite blocks including a steel shell surrounded by firebrick. Tantalum absorber rods are used in the receptacle and bed. 9 claims, 22 figures.

  12. Magnetic switch for reactor control rod. [LMFBR

    DOEpatents

    Germer, J.H.

    1982-09-30

    A magnetic reed switch assembly is described for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electro-magnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  13. D7 debris-bed experiment. [LMFBR

    SciTech Connect

    Mitchell, G W; Ottinger, C A; Lipinski, R J

    1983-08-01

    The D7 experiment investigated heat removal from a shallow, stratified bed of UO/sub 2/ particulate in sodium. The particle diameters ranged from 0.1 to 1.0 mm, with the largest particles at the bottom. The bed thickness was 74 mm and the average porosity was 41%. The incipient dryout power varied from 0.43 W/g to 0.25 W/g as the sodium subcooling (saturation temperature minus overlying pool temperature) was reduced from 390/sup 0/C to 170/sup 0/C. These powers were only slighlty above the incipient boiling powers. Such low dryout powers are believed due to the interaction of capillary force with bed stratification. With a subccoling of 130/sup 0/C several sudden decreases in the saturation temperature occurred. These are believed due to channel formation, which causes a reduction in the capillary pressure in the bed.

  14. Automatic safety rod for reactors. [LMFBR

    DOEpatents

    Germer, J.H.

    1982-03-23

    An automatic safety rod for a nuclear reactor containing neutron absorbing material and designed to be inserted into a reactor core after a loss-of-flow. Actuation is based upon either a sudden decrease in core pressure drop or the pressure drop decreases below a predetermined minimum value. The automatic control rod includes a pressure regulating device whereby a controlled decrease in operating pressure due to reduced coolant flow does not cause the rod to drop into the core.

  15. DOS: the discrete-ordinates system. [LMFBR

    SciTech Connect

    Rhoades, W. A.; Emmett, M. B.

    1982-09-01

    The Discrete Ordinates System determines the flux of neutrons or photons due either to fixed sources specified by the user or to sources generated by particle interaction with the problem materials. It also determines numerous secondary results which depend upon flux. Criticality searches can be performed. Numerous input, output, and file manipulation facilities are provided. The DOS driver program reads the problem specification from an input file and calls various program modules into execution as specified by the input file.

  16. Alien Sunset (Artist Concept)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Our solitary sunsets here on Earth might not be all that common in the grand scheme of things. New observations from NASA's Spitzer Space Telescope have revealed that mature planetary systems -- dusty disks of asteroids, comets and possibly planets -- are more frequent around close-knit twin, or binary, stars than single stars like our sun. That means sunsets like the one portrayed in this artist's photo concept, and more famously in the movie 'Star Wars,' might be quite commonplace in the universe.

    Binary and multiple-star systems are about twice as abundant as single-star systems in our galaxy, and, in theory, other galaxies. In a typical binary system, two stars of roughly similar masses twirl around each other like pair-figure skaters. In some systems, the two stars are very far apart and barely interact with each other. In other cases, the stellar twins are intricately linked, whipping around each other quickly due to the force of gravity.

    Astronomers have discovered dozens of planets that orbit around a single member of a very wide stellar duo. Sunsets from these worlds would look like our own, and the second sun would just look like a bright star in the night sky.

    But do planets exist in the tighter systems, where two suns would dip below a planet's horizon one by one? Unveiling planets in these systems is tricky, so astronomers used Spitzer to look for disks of swirling planetary debris instead. These disks are made of asteroids, comets and possibly planets. The rocky material in them bangs together and kicks up dust that Spitzer's infrared eyes can see. Our own solar system is swaddled in a similar type of disk.

    Surprisingly, Spitzer found more debris disks around the tightest binaries it studied (about 20 stars) than in a comparable sample of single stars. About 60 percent of the tight binaries had disks, while the single stars only had about 20 percent. These snug binary systems are as close or closer than just three times the

  17. Basic concepts of epigenetics

    PubMed Central

    Mazzio, Elizabeth A

    2012-01-01

    Through epigenetic modifications, specific long-term phenotypic consequences can arise from environmental influence on slowly evolving genomic DNA. Heritable epigenetic information regulates nucleosomal arrangement around DNA and determines patterns of gene silencing or active transcription. One of the greatest challenges in the study of epigenetics as it relates to disease is the enormous diversity of proteins, histone modifications and DNA methylation patterns associated with each unique maladaptive phenotype. This is further complicated by a limitless combination of environmental cues that could alter the epigenome of specific cell types, tissues, organs and systems. In addition, complexities arise from the interpretation of studies describing analogous but not identical processes in flies, plants, worms, yeast, ciliated protozoans, tumor cells and mammals. This review integrates fundamental basic concepts of epigenetics with specific focus on how the epigenetic machinery interacts and operates in continuity to silence or activate gene expression. Topics covered include the connection between DNA methylation, methyl-CpG-binding proteins, transcriptional repression complexes, histone residues, histone modifications that mediate gene repression or relaxation, histone core variant stability, H1 histone linker flexibility, FACT complex, nucleosomal remodeling complexes, HP1 and nuclear lamins. PMID:22395460

  18. Free radical propulsion concept

    NASA Technical Reports Server (NTRS)

    Hawkins, C. E.; Nakanishi, S.

    1981-01-01

    The concept of a free radical propulsion system, utilizing the recombination energy of dissociated low molecular weight gases to produce thrust, is analyzed. The system, operating at a theoretical impulse with hydrogen, as high as 2200 seconds at high thrust to power ratio, is hypothesized to bridge the gap between chemical and electrostatic propulsion capabilities. A comparative methodology is outlined by which characteristics of chemical and electric propulsion for orbit raising mission can be investigated. It is noted that free radicals proposed in rockets previously met with difficulty and complexity in terms of storage requirements; the present study proposes to eliminate the storage requirements by using electric energy to achieve a continuous-flow product of free radicals which are recombined to produce a high velocity propellant. Microwave energy used to dissociate a continuously flowing gas is transferred to the propellant via three-body-recombination for conversion to propellant kinetic energy. Microwave plasma discharge was found in excess of 90 percent over a broad range of pressure in preliminary experiments, and microwave heating compared to electrothermal heating showed much higher temperatures in gasdynamic equations.

  19. Medicinal plants: conception / contraception.

    PubMed

    Chaing, H S; Merino-chavez, G; Yang, L L; Wang, F N; Hafez, E S

    1994-01-01

    Researchers have conducted considerable experiments on the effectiveness and therapeutic values of Chinese herbs and parts of plants. We should not ignore the significance of natural medicine. The Chinese have been perfecting medicinal therapy based on the raw ingredients of plants/herbs and their derivatives for thousands of years. Chinese practitioners of traditional medicine prescribe medicines based on yin and yang. Traditional medicine is communicated in a verb or written form. Natural resources used in traditional medicine to treat diseases are not limited to just medicinal plants but also include animals, shell fish, and minerals. Parts of plants used in traditional medicine are leaves, stems, flowers, bark, and root. Chinese medicine is the world's oldest continuous surviving tradition. The Chinese experimented with local plants, often resulting in mild to violent reactions. This process allowed them to become familiar with poisonous plants and those that could relieve pain or successfully treat illness. Current allopathic medicines are composed of synthetic compounds copied from natural chemical derivatives, which tend to be more potent than the original compound. Some medicinal plants used to effect conception/contraception include Striga astiatica (contraceptive); Eurycoma longifolia (male virility); and a mixture of lengkuas, mengkudu masak, black pepper seeds, ginger, salt, and 2 eggs (increase libido). Women in Malaysia take jamu to preserve their body shape and to provide nutrition during pregnancy. Praneem causes local cell-mediated immunity in the uterus. Clinical trials of Praneem with or without the hCG vaccine are planned.

  20. Rapid adhesive bonding concepts

    NASA Technical Reports Server (NTRS)

    Stein, B. A.; Tyeryar, J. R.; Hodges, W. T.

    1984-01-01

    Adhesive bonding in the aerospace industry typically utilizes autoclaves or presses which have considerable thermal mass. As a consequence, the rates of heatup and cooldown of the bonded parts are limited and the total time and cost of the bonding process is often relatively high. Many of the adhesives themselves do not inherently require long processing times. Bonding could be performed rapidly if the heat was concentrated in the bond lines or at least in the adherends. Rapid adhesive bonding concepts were developed to utilize induction heating techniques to provide heat directly to the bond line and/or adherends without heating the entire structure, supports, and fixtures of a bonding assembly. Bonding times for specimens are cut by a factor of 10 to 100 compared to standard press bonding. The development of rapid adhesive bonding for lap shear specimens (per ASTM D1003 and D3163), for aerospace panel bonding, and for field repair needs of metallic and advanced fiber reinforced polymeric matrix composite structures are reviewed.

  1. The Master Protocol Concept.

    PubMed

    Redman, Mary W; Allegra, Carmen J

    2015-10-01

    During the past decade, biomedical technologies have undergone an explosive evolution-from the publication of the first complete human genome in 2003, after more than a decade of effort and at a cost of hundreds of millions of dollars-to the present time, where a complete genomic sequence can be available in less than a day and at a small fraction of the cost of the original sequence. The widespread availability of next-generation genomic sequencing has opened the door to the development of precision oncology. The need to test multiple new targeted agents both alone and in combination with other targeted therapies, as well as classic cytotoxic agents, demands the development of novel therapeutic platforms (particularly Master Protocols) capable of efficiently and effectively testing multiple targeted agents or targeted therapeutic strategies in relatively small patient subpopulations. Here, we describe the Master Protocol concept, with a focus on the expected gains and complexities of the use of this design. An overview of Master Protocols currently active or in development is provided along with a more extensive discussion of the Lung Master Protocol (Lung-MAP study).

  2. Lighting innovations in concept cars

    NASA Astrophysics Data System (ADS)

    Berlitz, Stephan; Huhn, Wolfgang

    2005-02-01

    Concept cars have their own styling process. Because of the big media interest they give a big opportunity to bring newest technology with styling ideas to different fairgrounds. The LED technology in the concept cars Audi Pikes Peak, Nuvolari and Le Mans will be explained. Further outlook for the Audi LED strategy starting with LED Daytime Running Lamp will be given. The close work between styling and technical engineers results in those concept cars and further technical innovations based on LED technologies.

  3. Mathematical Concepts and Maple Animations

    NASA Astrophysics Data System (ADS)

    Siddique, Mohammad; Mitchell, Kristy

    2010-09-01

    Maple is a mathematics software package, which contains graphic, computation, and programming tools. Maple animation is a powerful tool that can help in comprehending many fundamental concepts in mathematics and other sciences. This paper deals with the use of maple animation to demonstrate many fundamental concepts in mathematics that are difficult to explain verbally or through static figures. We show Maple animations effectively convey different concepts. We present problems taken from the literature to exemplify and explain Maple animation procedures. Using Maple in teaching mathematics facilitates the students with a tool to experiment and visualize complicated mathematical concepts and thus, strengthen their grasp of the subject.

  4. Students' Alternative Conceptions and Scientifically Acceptable Conceptions about Gravity.

    ERIC Educational Resources Information Center

    Palmer, David

    2001-01-01

    Identifies students' conceptions that could be categorized as scientifically acceptable and investigates the nature of any possible relationship between these concepts. Investigates 6th and 10th grade students' ideas on whether gravity acted upon a series of moving or non-moving objects in everyday situations. (Contains 41 references.) (Author/YDS)

  5. ADVANCED SULFUR CONTROL CONCEPTS

    SciTech Connect

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  6. Generic concepts in Nectriaceae

    PubMed Central

    Lombard, L.; van der Merwe, N.A.; Groenewald, J.Z.; Crous, P.W.

    2015-01-01

    The ascomycete family Nectriaceae (Hypocreales) includes numerous important plant and human pathogens, as well as several species used extensively in industrial and commercial applications as biodegraders and biocontrol agents. Members of the family are unified by phenotypic characters such as uniloculate ascomata that are yellow, orange-red to purple, and with phialidic asexual morphs. The generic concepts in Nectriaceae are poorly defined, since DNA sequence data have not been available for many of these genera. To address this issue we performed a multi-gene phylogenetic analysis using partial sequences for the 28S large subunit (LSU) nrDNA, the internal transcribed spacer region and intervening 5.8S nrRNA gene (ITS), the large subunit of the ATP citrate lyase (acl1), the RNA polymerase II largest subunit (rpb1), RNA polymerase II second largest subunit (rpb2), α-actin (act), β-tubulin (tub2), calmodulin (cmdA), histone H3 (his3), and translation elongation factor 1-alpha (tef1) gene regions for available type and authentic strains representing known genera in Nectriaceae, including several genera for which no sequence data were previously available. Supported by morphological observations, the data resolved 47 genera in the Nectriaceae. We re-evaluated the status of several genera, which resulted in the introduction of six new genera to accommodate species that were initially classified based solely on morphological characters. Several generic names are proposed for synonymy based on the abolishment of dual nomenclature. Additionally, a new family is introduced for two genera that were previously accommodated in the Nectriaceae. PMID:26955195

  7. Teaching Population Concepts. Revised Edition.

    ERIC Educational Resources Information Center

    King, Pat; Landahl, John

    This edition is designed to help teachers provide their students with some basic population concepts with stress placed on the elements of decision making. In the first section of the pamphlet, some of the basic concepts of population study are presented. These include populations, growth rates, birth and death rates, doubling time, migration, age…

  8. Conceptions of Workplace University Education.

    ERIC Educational Resources Information Center

    Martin, Elaine

    1998-01-01

    A study examined how academic staff involved in workplace supervision of students conceive of the workplace experience in four professional areas: engineering, business administration, health sciences, and social science. Five concepts are identified, and a relationship is seen between the conceptions and the quality of student learning. Staff…

  9. Caregiving: A Qualitative Concept Analysis

    ERIC Educational Resources Information Center

    Hermanns, Melinda; Mastel-Smith, Beth

    2012-01-01

    A common definition of caregiving does not exist. In an attempt to define the concept of caregiving, the authors used a hybrid qualitative model of concept development to analyze caregiving. The model consists of three phases: (a) theoretical, (b) fieldwork, and (c) analytical. The theoretical phase involves conducting an interdisciplinary…

  10. Mental Models of Boolean Concepts

    ERIC Educational Resources Information Center

    Goodwin, Geoffrey P.; Johnson-Laird, P. N.

    2011-01-01

    Negation, conjunction, and disjunction are major building blocks in the formation of concepts. This article presents a new model-based theory of these Boolean components. It predicts that individuals simplify the models of instances of concepts. Evidence corroborates the theory and challenges alternative accounts, such as those based on minimal…

  11. Concept Maps in Introductory Statistics

    ERIC Educational Resources Information Center

    Witmer, Jeffrey A.

    2016-01-01

    Concept maps are tools for organizing thoughts on the main ideas in a course. I present an example of a concept map that was created through the work of students in an introductory class and discuss major topics in statistics and relationships among them.

  12. Vocational Maturity and Self Concepts.

    ERIC Educational Resources Information Center

    Helbing, Hans

    The relationship between separate dimensions of vocational maturity and different self-concept and identity variables were examined. Subjects were Dutch students, age 14-18 years. The vocational maturity dimensions were measured by Dutch adaptations of American vocational maturity scales. Instruments for self-concept and identity measurement were…

  13. Finnish Teachers' Conceptions of Giftedness

    ERIC Educational Resources Information Center

    Laine, Sonja; Kuusisto, Elina; Tirri, Kirsi

    2016-01-01

    This article presents two independent studies of Finnish teachers' conceptions of giftedness and considers whether it is a malleable or fixed quality. The first qualitative study examined elementary school teachers' (N = 212) conceptions via inductive-oriented content analysis, whereas the second study measured teachers' (elementary n = 184,…

  14. Changing Conceptions of Activation Energy.

    ERIC Educational Resources Information Center

    Pacey, Philip D.

    1981-01-01

    Provides background material which relates to the concept of activation energy, fundamental in the study of chemical kinetics. Compares the related concepts of the Arrhenius activation energy, the activation energy at absolute zero, the enthalpy of activation, and the threshold energy. (CS)

  15. A concept analysis of otherness.

    PubMed

    Ryan, Jane Greene

    2012-01-01

    Otherness is an important concept in understanding the health provider-patient relationship and in creating insights into how to be more present with patients and families. This is an analysis of the concept of Otherness that leads to a definition of the construct.

  16. Learning to Use Scientific Concepts

    ERIC Educational Resources Information Center

    Wells, Gordon

    2008-01-01

    In responding to the research on conceptual change, this article attempts to make two points. First, scientific concepts are not possessed by individuals; rather, they are part of a culture's resources, which individuals learn to use for their own or for group purposes. Second, particular concepts are most effectively mastered when the learner is…

  17. Developing the Concept of Metalearning

    ERIC Educational Resources Information Center

    Jackson, Norman

    2004-01-01

    The idea of metalearning was originally used by John Biggs (1985) to describe the state of 'being aware of and taking control of one's own learning'. This paper explores the concept through collaborative enquiry involving researchers and higher education teachers. An evolved conception is proposed in which metalearning is a subconcept within…

  18. Mnemonic Instruction of Science Concepts.

    ERIC Educational Resources Information Center

    Mastropieri, Margo A.; And Others

    1988-01-01

    Eight behavior disordered students (ages 7-11) in a self-contained class were given two units of instruction in science concepts in a crossover design, with each student receiving both mnemonic and traditional instruction. Student learning was significantly improved under mnemonic instruction, and high levels of concept retention were…

  19. Developing an Action Concept Inventory

    ERIC Educational Resources Information Center

    McGinness, Lachlan P.; Savage, C. M.

    2016-01-01

    We report on progress towards the development of an Action Concept Inventory (ACI), a test that measures student understanding of action principles in introductory mechanics and optics. The ACI also covers key concepts of many-paths quantum mechanics, from which classical action physics arises. We used a multistage iterative development cycle for…

  20. Prison Rehabilitation: Concept Associates, Inc.

    ERIC Educational Resources Information Center

    McCoy, Robert D.

    1973-01-01

    A self-help project called Concept Associates, Inc., was started at Parish Prison in New Orleans. While most penal rehabilitation programs educate inmates and teach them a trade, the work of Concept is more thorough. The inmates aid each other with their problems by concentrating on inner changes and the power of positive thinking through four…

  1. Concept Empiricism: A Methodological Critique

    ERIC Educational Resources Information Center

    Machery, Edouard

    2007-01-01

    Thanks to Barsalou's, Damasio's, Glenberg's, Prinz' and others' work, neo-empiricism is gaining a deserved recognition in the psychology and philosophy of concepts. I argue, however, that neo-empiricists have underestimated the difficulty of providing evidence against the amodal approach to concepts and higher cognition. I highlight three key…

  2. Science Club--A Concept

    ERIC Educational Resources Information Center

    Wegner, Claas; Issak, Nicole; Tesch, Katharina; Zehne, Carolin

    2016-01-01

    The following article presents a concept of a science club which was developed by two master's students as a part of their thesis and which has been developed and improved ever since. The extra-curricular concept emphasises pupils' individuality through focusing on problem based leaning, station learning, and mixed age groups. Having joined the…

  3. Fijian Teachers' Conceptions of Assessment

    ERIC Educational Resources Information Center

    Dayal, Hem Chand; Lingam, Govinda Ishwar

    2015-01-01

    Teacher's conceptions are important as they could have a strong influence on their professional practices. This study set out to explore Fijian teacher's conceptions of assessment. Seventy teachers enrolled in an assessment course at a university in Fiji were involved in this study. Data was collected by asking teachers to write a reflection on…

  4. The Greek Concept of "Techne."

    ERIC Educational Resources Information Center

    Byrum, C. Stephen

    The Greek concept of techne can aid in understanding technological society and the way it can generate a separation of business and personal lives. As used by the early Greeks, techne mean the knowledge required to get the job done. The "manager" of today epitomizes this early concept. He is trained to get the job done efficiently,…

  5. Children's Death Concepts and Ethnicity.

    ERIC Educational Resources Information Center

    Wass, Hannelore; Towry, Betty J.

    1980-01-01

    Relationships between death concepts of Black and White children and their racial status were examined. Lower-middle-class elementary children completed a four-item questionnaire on death. Most children defined death as the end of living and listed physical causes as the explanation of death. In general, children's death concepts were similar.…

  6. New Concepts in Industrial Arts.

    ERIC Educational Resources Information Center

    American Industrial Arts Association, Washington, DC.

    The 30th annual American Industrial Arts Association (AIAA) Convention was held in Minneapolis in 1968. Topics for the AIAA general session addresses were: (1) "A Fresh Look at Industrial Arts," (2) "New Curricular Concepts," (3) "Making Education Relevant," (4) "Industrial Arts in an Educational System for the Seventies," (5) "New Concepts in…

  7. Advanced Turbulence Modeling Concepts

    NASA Technical Reports Server (NTRS)

    Shih, Tsan-Hsing

    2005-01-01

    The ZCET program developed at NASA Glenn Research Center is to study hydrogen/air injection concepts for aircraft gas turbine engines that meet conventional gas turbine performance levels and provide low levels of harmful NOx emissions. A CFD study for ZCET program has been successfully carried out. It uses the most recently enhanced National combustion code (NCC) to perform CFD simulations for two configurations of hydrogen fuel injectors (GRC- and Sandia-injector). The results can be used to assist experimental studies to provide quick mixing, low emission and high performance fuel injector designs. The work started with the configuration of the single-hole injector. The computational models were taken from the experimental designs. For example, the GRC single-hole injector consists of one air tube (0.78 inches long and 0.265 inches in diameter) and two hydrogen tubes (0.3 inches long and 0.0226 inches in diameter opposed at 180 degree). The hydrogen tubes are located 0.3 inches upstream from the exit of the air element (the inlet location for the combustor). To do the simulation, the single-hole injector is connected to a combustor model (8.16 inches long and 0.5 inches in diameter). The inlet conditions for air and hydrogen elements are defined according to actual experimental designs. Two crossing jets of hydrogen/air are simulated in detail in the injector. The cold flow, reacting flow, flame temperature, combustor pressure and possible flashback phenomena are studied. Two grid resolutions of the numerical model have been adopted. The first computational grid contains 0.52 million elements, the second one contains over 1.3 million elements. The CFD results have shown only about 5% difference between the two grid resolutions. Therefore, the CFD result obtained from the model of 1.3-million grid resolution can be considered as a grid independent numerical solution. Turbulence models built in NCC are consolidated and well tested. They can handle both coarse and

  8. Learning to use scientific concepts

    NASA Astrophysics Data System (ADS)

    Wells, Gordon

    2008-07-01

    In responding to the research on conceptual change, this article attempts to make two points. First, scientific concepts are not possessed by individuals; rather, they are part of a culture's resources, which individuals learn to use for their own or for group purposes. Second, particular concepts are most effectively mastered when the learner is deeply engaged in solving a problem for which they function as effective semiotic tools in achieving a solution. On these grounds, it is argued that the mastering of scientific concepts is best achieved through learning to use them in motivated inquiry.

  9. SSF growth concepts and configurations

    NASA Technical Reports Server (NTRS)

    Cirillo, William M.

    1991-01-01

    There are three primary objectives for the Space Station Freedom (SSF) Growth concepts and configuration study task. The first objective is the development of evolutionary SSF concept consistent with user requirements and program constraints. The second primary objective is to ensure the feasibility of the proposed SSF evolution concepts as the systems level. This includes an assessment of SSF evolution flight control analysis, logistics assessment, maintainability, and operational considerations. The final objective is to ensure compatibility of the baseline SSF design with the derived evolution requirements at both the system and element (habitat modules, power generation equipment, etc.) levels.

  10. Concept Model on Topological Learning

    NASA Astrophysics Data System (ADS)

    Ae, Tadashi; Kioi, Kazumasa

    2010-11-01

    We discuss a new model for concept based on topological learning, where the learning process on the neural network is represented by mathematical topology. The topological learning of neural networks is summarized by a quotient of input space and the hierarchical step induces a tree where each node corresponds to a quotient. In general, the concept acquisition is a difficult problem, but the emotion for a subject is represented by providing the questions to a person. Therefore, a kind of concept is captured by such data and the answer sheet can be mapped into a topology consisting of trees. In this paper, we will discuss a way of mapping the emotional concept to a topological learning model.

  11. The Concept of Action Research.

    ERIC Educational Resources Information Center

    Altrichter, Herbert; Kemmis, Stephen; McTaggart, Robin; Zuber-Skerritt, Ortrun

    2002-01-01

    Explains why definition of action research is problematic and presents working definitions developed internationally that indicate its nature, philosophy, and methodology. Suggests that pragmatic approaches to definition serve communication purposes without narrowly confining the concept. (SK)

  12. Solar Sail Control Actuator Concepts

    NASA Technical Reports Server (NTRS)

    Mangus, David; Heaton, Andy

    2004-01-01

    The thrust produced by a solar sail is a direct function of its attitude. Thus, solar sail thrust vector control is a key technology that must be developed for sailcraft to become a viable form of deep-space transportation. The solar sail community has been studying various sail Attitude Control System (ACS) actuator designs for near Earth orbit as well as deep space missions. These actuators include vanes, spreader bars, two-axis gimbals, floating/locking gimbals with wheels, and translating masses. This paper documents the various concepts and performs an assessment at the highest level. This paper will only compare the various ACS actuator concepts as they stand at the publication time. This is not an endorsement of any particular concept. As concepts mature, the assessments will change.

  13. Prometheus Hot Leg Piping Concept

    NASA Astrophysics Data System (ADS)

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-01

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  14. Promethus Hot Leg Piping Concept

    SciTech Connect

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  15. [Concept analysis of workplace bullying].

    PubMed

    Ma, Shu-Ching; Wang, Hsiu-Hung; Chen, Jih-Yuan

    2011-08-01

    Workplace bullying is a complicated and imprecise concept. Research findings have highlighted it as an important issue in the nursing environment worldwide. Workplace bullying arises due to malfunctions in workplace organizational and cultural related antecedents and manifests in various forms. Many studies have reported that nurses experiencing workplace bullying face increased levels of physical, psychological and social distress, may adopt suicidal thoughts and negativity towards the nursing profession, and may even abandon the nursing profession completely. Although a large number of papers have discussed the antecedents, forms and interventions related to workplace bullying, there has yet been no systematic concept analysis of workplace bullying. This paper applied Walker and Avant's concept analysis process to verify concept definitions, identify defining attributes, antecedents, and consequences, and provide examples of model, borderline, and contrary cases. Findings can help nursing administrators understand and clarify the meaning of workplace bullying in order to take appropriate measures to improve the working environment for nursing professionals.

  16. Prometheus Hot Leg Piping Concept

    SciTech Connect

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-30

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  17. Professionalism: evolution of the concept.

    PubMed

    van Mook, Walther N K A; de Grave, Willem S; Wass, Valerie; O'Sullivan, Helen; Zwaveling, Jan Harm; Schuwirth, Lambert W; van der Vleuten, Cees P M

    2009-07-01

    The concept of professionalism has undergone major changes over the millennia in general and the last century specifically. This article, the first in a series of articles in this Journal on professionalism, attempts to provide the reader with a historical overview of the evolution of the concept of professionalism over time. As a result of these changes, medical school curricula, and contemporary specialist training programs are increasingly becoming competence based, with professionalism becoming an integral part of a resident's training and assessment program.

  18. Rover concepts for lunar exploration

    NASA Technical Reports Server (NTRS)

    Connolly, John F.

    1993-01-01

    The paper describes the requirements and design concepts developed for the First Lunar Outpost (FLO) and the follow-on lunar missions by the Human Planet Surface Project Office at the Johnson Space Center, which include inputs from scientists, technologists, operators, personnel, astronauts, mission designers, and program managers. Particular attention is given to the requirements common to all rover concepts, the precursor robotic missions, the FLO scenario and capabilities, and the FLO evolution.

  19. Developing an action concept inventory

    NASA Astrophysics Data System (ADS)

    McGinness, Lachlan P.; Savage, C. M.

    2016-06-01

    We report on progress towards the development of an Action Concept Inventory (ACI), a test that measures student understanding of action principles in introductory mechanics and optics. The ACI also covers key concepts of many-paths quantum mechanics, from which classical action physics arises. We used a multistage iterative development cycle for incorporating expert and student feedback into successive revisions of the ACI. The student feedback, including think-aloud interviews, enabled us to identify their misconceptions about action physics.

  20. Concepts in viral pathogenesis II

    SciTech Connect

    Notkins, A.L.; Oldstone, M.B.A.

    1986-01-01

    This paper contains papers divided among 10 sections. The section titles are: Viral Structure and Function; Viral Constructs; Oncogenes, Transfection, and Differentiation; Viral Tropism and Entry into Cells; Immune Recognition of Viruses; Evolving Concepts in Viral Pathogenesis Illustrated by Selected Plant and Animal Models; Evolving Concepts in Viral Pathogenesis Illustrated by Selected Diseases in Humans; New Trends in Diagnosis and Epidemiology; and Vaccines and Antiviral Therapy.

  1. Supersonic Retropropulsion Flight Test Concepts

    NASA Technical Reports Server (NTRS)

    Post, Ethan A.; Dupzyk, Ian C.; Korzun, Ashley M.; Dyakonov, Artem A.; Tanimoto, Rebekah L.; Edquist, Karl T.

    2011-01-01

    NASA's Exploration Technology Development and Demonstration Program has proposed plans for a series of three sub-scale flight tests at Earth for supersonic retropropulsion, a candidate decelerator technology for future, high-mass Mars missions. The first flight test in this series is intended to be a proof-of-concept test, demonstrating successful initiation and operation of supersonic retropropulsion at conditions that replicate the relevant physics of the aerodynamic-propulsive interactions expected in flight. Five sub-scale flight test article concepts, each designed for launch on sounding rockets, have been developed in consideration of this proof-of-concept flight test. Commercial, off-the-shelf components are utilized as much as possible in each concept. The design merits of the concepts are compared along with their predicted performance for a baseline trajectory. The results of a packaging study and performance-based trade studies indicate that a sounding rocket is a viable launch platform for this proof-of-concept test of supersonic retropropulsion.

  2. Spiritual Health: A Concept Analysis.

    PubMed

    Jaberi, Azita; Momennasab, Marzieh; Yektatalab, Shahrzad; Ebadi, Abbas; Cheraghi, Mohammad Ali

    2017-03-10

    Spiritual health has attracted a lot of attention in health-related and nursing sciences and numerous researches. Yet, this concept has remained complex and ambiguous, and there is no consensus in this regard. This ambiguity can be challenging for holistic nursing; therefore, clarification of the concept is required for development of nursing knowledge. The present study aimed to explore the concept of spiritual health in health-related and nursing literature. Walker and Avant (Strategies for theory construction in nursing, Appleton & Lange, Norwalk, 1995) concept analysis method was used in this study. The results were categorized as antecedents, attributes, and outcomes of spiritual health. The critical attributes extracted for spiritual health included transcendence, purposefulness and meaningfulness, faithfulness, harmonious interconnectedness, integrative power, multidimensionality, and holistic being. Besides, the antecedents of spiritual health included capability and potentiality for transcendence, and spiritual awareness. Finally, well-being and moral development were the outcomes of spiritual health. Spiritual health is one of the basic aspects of health and providing a clear theoretical definition can result in a common understanding of this concept for nurses. Clarifying this concept would also be useful for provision of spiritual care interventions and development of nursing theories.

  3. Unity amidst heterogeneity in theories of concepts.

    PubMed

    Edwards, Kevan

    2010-06-01

    This commentary raises two concerns with Machery's approach in Doing without Concepts. The first concern is that it may be possible to preserve a unified theory of concepts by distinguishing facts about concept individuation from facts about cognitive structures and processes. The second concern questions the sharpness of the distinction Machery draws between psychological and philosophical conceptions of concepts.

  4. Key Concepts in Adult Education and Training.

    ERIC Educational Resources Information Center

    Tight, Malcolm

    This book defines and explains some 40 key concepts in adult education and training, and it presents an analysis of the more than 150 concepts that can be made by combining core and qualifying concepts. The concepts have been grouped into seven chapters, with the following core concepts discussed in chapter 1: adult, education, and training, plus…

  5. High Altitude Venus Operational Concept (HAVOC): Proofs of Concept

    NASA Technical Reports Server (NTRS)

    Jones, Christopher A.; Arney, Dale C.; Bassett, George Z.; Clark, James R.; Hennig, Anthony I.; Snyder, Jessica C.

    2015-01-01

    The atmosphere of Venus is an exciting destination for both further scientific study and future human exploration. A recent internal NASA study of a High Altitude Venus Operational Concept (HAVOC) led to the development of an evolutionary program for the exploration of Venus, with focus on the mission architecture and vehicle concept for a 30-day crewed mission into Venus's atmosphere at 50 kilometers. Key technical challenges for the mission include performing the aerocapture maneuvers at Venus and Earth, inserting and inflating the airship at Venus during the entry sequence, and protecting the solar panels and structure from the sulfuric acid in the atmosphere. Two proofs of concept were identified that would aid in addressing some of the key technical challenges. To mitigate the threat posed by the sulfuric acid ambient in the atmosphere of Venus, a material was needed that could protect the systems while being lightweight and not inhibiting the performance of the solar panels. The first proof of concept identified candidate materials and evaluated them, finding FEP-Teflon (Fluorinated Ethylene Propylene-Teflon) to maintain 90 percent transmittance to relevant spectra even after 30 days of immersion in concentrated sulfuric acid. The second proof of concept developed and verified a packaging algorithm for the airship envelope to inform the entry, descent, and inflation analysis.

  6. Time Concepts for Elementary School Children.

    ERIC Educational Resources Information Center

    Muir, Sharon Pray

    1990-01-01

    Points out that children have difficulty learning time concepts. Presents instructional activities for concepts associated with clocks, calendars, and chronology. Outlines Jerome Bruner's three different stages of representation for each concept: enactive, iconic, and symbolic. (DB)

  7. Metagenomics and the niche concept.

    PubMed

    Marco, Diana

    2008-08-01

    The metagenomics approach has revolutionised the fields of bacterial diversity, ecology and evolution, as well as derived applications like bioremediation and obtaining bioproducts. A further associated conceptual change has also occurred since in the metagenomics methodology the species is no longer the unit of study, but rather partial genome arrangements or even isolated genes. In spite of this, concepts coming from ecological and evolutionary fields traditionally centred on the species, like the concept of niche, are still being applied without further revision. A reformulation of the niche concept is necessary to deal with the new operative and epistemological challenges posed by the metagenomics approach. To contribute to this end, I review past and present uses of the niche concept in ecology and in microbiological studies, showing that a new, updated definition need to be used in the context of the metagenomics. Finally, I give some insights into a more adequate conceptual background for the utilisation of the niche concept in metagenomic studies. In particular, I raise the necessity of including the microbial genetic background as another variable into the niche space.

  8. Evaluation of advanced airship concepts

    NASA Technical Reports Server (NTRS)

    Joner, B. A.; Schneider, J. J.

    1975-01-01

    A historical overview of the airship, technical and operational characteristics of conventional and hybrid concepts, and the results of a parametric design analysis and evaluation are presented. The lift capabilities of certain buoyant fluids for a hypothetical 16 million cu.ft. volume airship are compared. The potential advanced airship concepts are surveyed, followed by a discussion of the six configurations: conventional nonrigid, conventional rigid, Deltoid (Dynairship), Guppoid (Megalifter), Helipsoid, and Heli-Stat. It is suggested that a partially buoyant Helipsoid concept of the optimum buoyancy ratio has the potential to solve the problems facing future airship development, such as Ballast and Ballast Recovery System, Full Low-Speed Controllability, Susceptibility to Wind/Gusting, Weather/Icing Constraints, Ground Handling/Hangaring, and Direct/Indirect Operating Costs.

  9. Changing Conceptions of Globalization: Changing Conceptions of Education.

    ERIC Educational Resources Information Center

    Fitzsimons, Patrick

    2000-01-01

    Examines changing conceptions of globalization in education, highlighting new electronic information technologies that, rather than promoting homogeneity, are producing a stimulus for a politics of difference. Cyborgs and cyberspace are emerging as discourses of disunity and difference. The essay recommends a form of critical localism to challenge…

  10. A Network Analysis of Concept Maps of Triangle Concepts

    ERIC Educational Resources Information Center

    Haiyue, Jin; Khoon Yoong, Wong

    2010-01-01

    Mathematics educators and mathematics standards of curriculum have emphasised the importance of constructing the interconnectedness among mathematic concepts ("conceptual understanding") instead of only the ability to carry out standard procedures in an isolated fashion. Researchers have attempted to assess the knowledge networks in…

  11. Effect of Concept Attainment Model on Acquisition of Physics Concepts

    ERIC Educational Resources Information Center

    Kumar, Amit; Mathur, Madhu

    2013-01-01

    Teaching a subject like physics needs special teaching methods. It has been felt that in spite of strenuous efforts of physics teacher, students fail to grasp the certain concepts of subject, which lead disinterest among students towards physics. More ever students are often unable to apply their knowledge to advance studies. Therefore there is a…

  12. Social Justice: A Concept Analysis.

    PubMed

    Matwick, Angela L; Woodgate, Roberta L

    2016-08-23

    Social justice is presented frequently as a core or shared value at the very foundation of nursing practice. Despite its acceptance as a core value, its use is varied and there has been inherent difficulty in establishing a definitive explanation for what is meant by social justice. As such, a clearly defined meaning for the concept of social justice does not exist in contemporary nursing literature. Following the method outlined by Walker and Avant, an analysis of the concept of social justice provides clarity to the meaning of social justice as it is used within the nursing profession, in academia, education, and practice.

  13. Some concepts in reaction dynamics.

    PubMed

    Polanyi, J C

    1987-05-08

    The objective in this work has been one which I have shared with the two other 1986 Nobel lecturers in chemistry, D. R. Herschbach and Y. T. Lee, as well as with a wide group of colleagues and co-workers who have been responsible for bringing this field to its current state. That state is summarized in the title; we now have some concepts relevant to the motions of atoms and molecules in simple reactions, and some examples of the application of these concepts. We are, however, richer in vocabulary than in literature. The great epics of reaction dynamics remain to be written. I shall confine myself to some simple stories.

  14. Multiwall TPS: An emerging concept

    NASA Technical Reports Server (NTRS)

    Shideler, J. L.; Kelly, H. N.; Avery, D. E.; Blosser, M. L.; Adelman, H. M.

    1981-01-01

    The transformation of a titanium multiwall thermal protection system from a conceptual design to a working reality is described. The thermal and structural performance of the basic multiwall concept is analyzed. Radiant heat, wind tunnel, vibration, acoustic, and lightning strike tests are used to verify the performance of multiwall tiles under representative operating conditions. Flat, all titanium multiwall configurations limited to temperature below 810 K are discussed. Curved surface, higher temperature versions of the multiwall are considered. Preliminary mass estimates for advanced multiwall concepts are presented.

  15. Concept empiricism: a methodological critique.

    PubMed

    Machery, Edouard

    2007-07-01

    Thanks to Barsalou's, Damasio's, Glenberg's, Prinz' and others' work, neo-empiricism is gaining a deserved recognition in the psychology and philosophy of concepts. I argue, however, that neo-empiricists have underestimated the difficulty of providing evidence against the amodal approach to concepts and higher cognition. I highlight three key problems: the difficulty of sorting out amodal predictions from neo-empiricist predictions, the difficulty of finding experimental tasks that are not best solved by imagery and the difficulty of generalizing findings concerning a given cognitive process in a given context to other cognitive processes or other contexts. Finally, solutions to these three problems are considered.

  16. CONCEPT IDENTIFICATION AS A FUNCTION OF INSTRUCTIONS, LABELS, SEQUENCE, CONCEPT TYPE, AND TEST ITEM TYPE.

    ERIC Educational Resources Information Center

    LYNCH, DANIEL O.

    THE EFFECTS OF INSTRUCTIONS, TYPE OF LABEL, TYPE OF CONCEPT, AND SEQUENCE OF CONCEPTS BY TYPE UPON CONCEPT IDENTIFICATION WERE INVESTIGATED IN THIS STUDY. PERFORMANCE WAS ANALYZED IN TERMS OF FOUR TYPES OF TEST ITEMS. INSTRUCTION, FOCUSING ON THE CONCEPT TO BE ATTAINED AND THE CONCEPT NATURE, WAS FOUND TO FACILITATE CONCEPT IDENTIFICATION…

  17. "Clicking through" or Learning Concepts

    ERIC Educational Resources Information Center

    Stidwell, Peter

    2005-01-01

    The author has developed an innovative science website resource that also shows how engineers use science. As well as addressing scientific facts and concepts, the resource also engages children in the process of scientific enquiry, using graph tools and data interpretation. Part of the resource helps children to understand that much of what they…

  18. Neural Representations of Physics Concepts.

    PubMed

    Mason, Robert A; Just, Marcel Adam

    2016-06-01

    We used functional MRI (fMRI) to assess neural representations of physics concepts (momentum, energy, etc.) in juniors, seniors, and graduate students majoring in physics or engineering. Our goal was to identify the underlying neural dimensions of these representations. Using factor analysis to reduce the number of dimensions of activation, we obtained four physics-related factors that were mapped to sets of voxels. The four factors were interpretable as causal motion visualization, periodicity, algebraic form, and energy flow. The individual concepts were identifiable from their fMRI signatures with a mean rank accuracy of .75 using a machine-learning (multivoxel) classifier. Furthermore, there was commonality in participants' neural representation of physics; a classifier trained on data from all but one participant identified the concepts in the left-out participant (mean accuracy = .71 across all nine participant samples). The findings indicate that abstract scientific concepts acquired in an educational setting evoke activation patterns that are identifiable and common, indicating that science education builds abstract knowledge using inherent, repurposed brain systems.

  19. Health as an analogical concept.

    PubMed

    Mordacci, R

    1995-10-01

    This article examines the normative structure of the concept of health and tries to suggest an account of it in a phenomenological-hermeneutic framework. It is argued that the concept of health has a logical priority to illness, though the latter has an experiential priority. The fundamental feature of the concept of health as discussed in the literature is initially recognized in the notion of 'norm', in both the bio-statistical and normative-ideal sense. An analysis of this body of literature reveals some weaknesses in bio-statistical definitions of health as well as in those normative ones which endorse a value-relativity thesis. An approach based on the analogical structure of language is then advanced. In this framework, the notion of biological normativeness proposed by G. Canguilhem is connected with an analysis of the language of health through etymologies. It is argued that health can be characterized as an analogy of 'plenitude', which is the common ideal reference of the various health-concepts. The analogical structuring of language allows the recognition of different levels of meaning, and therefore of different kinds of normativeness (biological, mental, social, moral). Some hints of a theory of health deriving from this framework are then given.

  20. Essentialism, word use, and concepts.

    PubMed

    Braisby, N; Franks, B; Hampton, J

    1996-06-01

    The essentialist approach to word meaning has been used to undermine the fundamental assumptions of the cognitive psychology of concepts. Essentialism assumes that a word refers to a natural kind category in virtue of category members possessing essential properties. In support of this thesis, Kripke and Putnam deploy various intuitions concerning word use under circumstances in which discoveries about natural kinds are made. Although some studies employing counterfactual discoveries and related transformations appear to vindicate essentialism, we argue that the intuitions have not been investigated exhaustively. In particular, we argue that discoveries concerning the essential properties of whole categories (rather than simply of particular category members) are critical to the essentialist intuitions. The studies reported here examine such discovery contexts, and demonstrate that words and concepts are not used in accordance with essentialism. The results are, however, consistent with "representational change" views of concepts, which are broadly Fregean in their motivation. We conclude that since essentialism is not vindicated by ordinary word use, it fails to undermine the cognitive psychology of concepts.

  1. Exotic power and propulsion concepts

    NASA Technical Reports Server (NTRS)

    Forward, Robert L.

    1990-01-01

    The status of some exotic physical phenomena and unconventional spacecraft concepts that might produce breakthroughs in power and propulsion in the 21st Century are reviewed. The subjects covered include: electric, nuclear fission, nuclear fusion, antimatter, high energy density materials, metallic hydrogen, laser thermal, solar thermal, solar sail, magnetic sail, and tether propulsion.

  2. Associative concept learning in animals.

    PubMed

    Zentall, Thomas R; Wasserman, Edward A; Urcuioli, Peter J

    2014-01-01

    Nonhuman animals show evidence for three types of concept learning: perceptual or similarity-based in which objects/stimuli are categorized based on physical similarity; relational in which one object/stimulus is categorized relative to another (e.g., same/different); and associative in which arbitrary stimuli become interchangeable with one another by virtue of a common association with another stimulus, outcome, or response. In this article, we focus on various methods for establishing associative concepts in nonhuman animals and evaluate data documenting the development of associative classes of stimuli. We also examine the nature of the common within-class representation of samples that have been associated with the same reinforced comparison response (i.e., many-to-one matching) by describing manipulations for distinguishing possible representations. Associative concepts provide one foundation for human language such that spoken and written words and the objects they represent become members of a class of interchangeable stimuli. The mechanisms of associative concept learning and the behavioral flexibility it allows, however, are also evident in the adaptive behaviors of animals lacking language.

  3. University Students' Conceptions of Function

    ERIC Educational Resources Information Center

    Evangelidou, Anastasia; Spyrou, Panayiotis; Elia, Iliada; Gagatsis, Athanasios

    2004-01-01

    "Function", as it is understood today, formulates one of the most important concepts of mathematics. Nevertheless, many students do not sufficiently understand the abstract but comprehensive meaning of function and problems concerning its didactical metaphor are often confronted. The present study examines the interpretation of the…

  4. A Semiprofessional Conception of Teaching.

    ERIC Educational Resources Information Center

    Tom, Alan R.

    1987-01-01

    Examines the Carnegie report in terms of three themes: (1) distrust of teachers; (2) commitment to teacher autonomy that is conditional on achieved results; and (3) a conception of teacher accountability focusing on student performance rather than professional practice. Concludes that the implicit view of the teacher is one of an assembly-line…

  5. On the Concept of Temperature.

    ERIC Educational Resources Information Center

    Tee, Tan Boon

    1979-01-01

    Discusses some of the misconceptions school children may have in their study of heat and temperature and attempts to clarify the concepts of temperature and to contrast it with the use of the term heat. The choice of gas thermometers as the standard temperature scale is also discussed. (HM)

  6. Workplace incivility: a concept analysis.

    PubMed

    Abolfazl Vagharseyyedin, Seyyed

    2015-01-01

    This study aimed to describe the meaning of the concept 'workplace incivility' and promote consistency in its application in nursing research and practice. The methodology introduced by Walker and Avant was used to analyze this concept. A total number of 50 studies that had essentially addressed the concept of incivility in employees' work environment was selected. Ambiguous intent, violation of mutual respect, low intensity and lack of physical assault were identified as the defining attributes of workplace incivility. The necessary antecedent of workplace incivility consisted of the presence of two or more people, with one or more as the source of the incivility, and another or others as its target in the workplace. Moreover, certain individual and organisational factors were the potential antecedents of workplace incivility. Possible negative outcomes for victims, witnesses, organisations, society and perpetrators of such behaviours, such as increased cost for the organisation, reduced citizenship performance, psychological distress and anxiety were identified as outcomes of workplace incivility. Results of the current concept analysis can guide nurse managers to design interventions so that the occurrence of workplace incivility can be reduced. Further studies can focus on testing the psychometric properties of the existing workplace incivility scales, especially uncivil behaviours experienced by nurses across different societies or cultures.

  7. Guide to the Concept: Interdependence.

    ERIC Educational Resources Information Center

    King, David C.

    This draft outline presents and organizes for teachers one of the fundamental concepts in war/peace studies: interdependence. As the definitional statement makes clear, interdependence involves learning to look at the world as a single system, and to identify and analyze its various subsystems. Part of the rationale for considering interdependence…

  8. The Concept of Transition System

    ERIC Educational Resources Information Center

    Raffe, David

    2008-01-01

    The term "transition system" describes features of a country's institutional arrangements which shape young people's education-work transitions. It explains why national differences in transition processes and outcomes persist despite apparent pressures for convergence. This paper asks how the concept of transition system has been…

  9. Implications of the HRD Concept.

    ERIC Educational Resources Information Center

    Nadler, Leonard

    1981-01-01

    Reviews the conceptual differences among the various kinds of learning experiences which are provided for adults, particularly by employing organizations. Also examines labels and semantics, implications of the various concepts, who should bear the responsibility for human resource development, mutual expectations, fade-out of unused skills, and…

  10. Threshold Concepts and Pedagogic Representation

    ERIC Educational Resources Information Center

    Meyer, Jan H. F.

    2016-01-01

    Purpose: The purpose of this paper is to present a brief exposure to the development of the threshold concepts framework (TCF), the intention being to illuminate for interested readers a broader landscape of research activity than that perhaps conveyed by the individual contributions to this special edition. Design/Methodology/Approach: There is…

  11. The Enrollment Analysis Matrix Concept.

    ERIC Educational Resources Information Center

    Chisholm, Mark

    The underlying assumptions and the structure of the enrollment analysis matrix (EAM) concept are discussed. EAM is a component of the Strategic Planning Project of the National Center for Higher Education Management Systems. EAM relates changes in the population of potential students external to the institution to the impacts that might result…

  12. Advanced nuclear thermal propulsion concepts

    NASA Technical Reports Server (NTRS)

    Howe, Steven D.

    1993-01-01

    In 1989, a Presidential directive created the Space Exploration Initiative (SEI) which had a goal of placing mankind on Mars in the early 21st century. The SEI was effectively terminated in 1992 with the election of a new administration. Although the initiative did not exist long enough to allow substantial technology development, it did provide a venue, for the first time in 20 years, to comprehensively evaluate advanced propulsion concepts which could enable fast, manned transits to Mars. As part of the SEI based investigations, scientists from NASA, DoE National Laboratories, universities, and industry met regularly and proceeded to examine a variety of innovative ideas. Most of the effort was directed toward developing a solid-core, nuclear thermal rocket and examining a high-power nuclear electric propulsion system. In addition, however, an Innovative Concepts committee was formed and charged with evaluating concepts that offered a much higher performance but were less technologically mature. The committee considered several concepts and eventually recommended that further work be performed in the areas of gas core fission rockets, inertial confinement fusion systems, antimatter based rockets, and gas core fission electric systems. Following the committee's recommendations, some computational modeling work has been performed at Los Alamos in certain of these areas and critical issues have been identified.

  13. ASSOCIATIVE CONCEPT LEARNING IN ANIMALS

    PubMed Central

    Zentall, Thomas R.; Wasserman, Edward A.; Urcuioli, Peter J.

    2014-01-01

    Nonhuman animals show evidence for three types of concept learning: perceptual or similarity-based in which objects/stimuli are categorized based on physical similarity; relational in which one object/stimulus is categorized relative to another (e.g., same/different); and associative in which arbitrary stimuli become interchangeable with one another by virtue of a common association with another stimulus, outcome, or response. In this article, we focus on various methods for establishing associative concepts in nonhuman animals and evaluate data documenting the development of associative classes of stimuli. We also examine the nature of the common within-class representation of samples that have been associated with the same reinforced comparison response (i.e., many-to-one matching) by describing manipulations for distinguishing possible representations. Associative concepts provide one foundation for human language such that spoken and written words and the objects they represent become members of a class of interchangeable stimuli. The mechanisms of associative concept learning and the behavioral flexibility it allows, however, are also evident in the adaptive behaviors of animals lacking language. PMID:24170540

  14. Solar Concepts: A Background Text.

    ERIC Educational Resources Information Center

    Gorham, Jonathan W.

    This text is designed to provide teachers, students, and the general public with an overview of key solar energy concepts. Various energy terms are defined and explained. Basic thermodynamic laws are discussed. Alternative energy production is described in the context of the present energy situation. Described are the principal contemporary solar…

  15. Handedness Shapes Children's Abstract Concepts

    ERIC Educational Resources Information Center

    Casasanto, Daniel; Henetz, Tania

    2012-01-01

    Can children's handedness influence how they represent abstract concepts like "kindness" and "intelligence"? Here we show that from an early age, right-handers associate rightward space more strongly with positive ideas and leftward space with negative ideas, but the opposite is true for left-handers. In one experiment, children indicated where on…

  16. The Concept of Developmental Learning.

    ERIC Educational Resources Information Center

    Fowler, William

    Cognitive developmental learning is a concept expressing the hypothesis that learning has a continuing, cumulative, and transformational function in the development of intelligence. Two important questions are, "How much do we know about methods?" and "What classes of knowledge and abilities should we develop?" An analysis of past investigations,…

  17. Culturing Conceptions: From First Principles

    ERIC Educational Resources Information Center

    Roth, Wolff-Michael; Lee, Yew Jin; Hwang, SungWon

    2008-01-01

    Over the past three decades, science educators have accumulated a vast amount of information on conceptions--variously defined as beliefs, ontologies, cognitive structures, mental models, or frameworks--that generally (at least initially) have been derived from interviews about certain topics. During the same time period, cultural studies has…

  18. Reproductive cell separation: A concept

    NASA Technical Reports Server (NTRS)

    Cutaia, A. J.

    1973-01-01

    Attempt has been made to separate mammalian male (Y) bearing sperm from female (X) bearing sperm. Both types of sperm are very dependent on gravity for their direction of movement. Proposed concept suggests electrophoretic force of suitable magnitude and direction may be effective means of separating X and Y sperm under zero gravity.

  19. Space Station medical sciences concepts

    NASA Technical Reports Server (NTRS)

    Mason, J. A. (Editor); Johnson, P. C., Jr. (Editor)

    1984-01-01

    Current life sciences concepts relating to Space Station are presented including the following: research, extravehicular activity, biobehavioral considerations, medical care, maintenance of dental health, maintaining health through physical conditioning and countermeasures, protection from radiation, atmospheric contamination control, atmospheric composition, noise pollution, food supply and service, clothing and furnishings, and educational program possibilities. Information on the current status of Soviet Space Stations is contained.

  20. Property Attribution in Combined Concepts

    ERIC Educational Resources Information Center

    Spalding, Thomas L.; Gagné, Christina L.

    2015-01-01

    Recent research shows that the judged likelihood of properties of modified nouns ("baby ducks have webbed feet") is reduced relative to judgments for unmodified nouns ("ducks have webbed feet"). This modification effect has been taken as evidence both for and against the idea that combined concepts automatically inherit…

  1. Conservation Concepts in Elementary Chemistry

    ERIC Educational Resources Information Center

    Hall, John Ruthven

    1973-01-01

    Studied effectiveness of teaching conservation of chemical identity, composition, and mass to 12 boys and 11 girls of ages ranging from 11.11 to 12.10, using techniques analogous to Piaget's. Indicated the necessity of course re-examination to facilitate attainment of conservation concepts. (CC)

  2. Altitude Compensating Nozzle Concepts Evaluation

    NASA Technical Reports Server (NTRS)

    Soni, Bharat

    2000-01-01

    This report contains the summary of work accomplished during summer of 2000 by Mr. Chad Hammons, undergraduate senior student, Mississippi State University/ERC in support of NASA/MSFC mission pertinent to Altitude compensating nozzle concepts evaluations. In particular, the development of automatic grid generator applicable in conducting sensitivity analysis involving Aerospike engine is described.

  3. Development of Conceptions of Education.

    ERIC Educational Resources Information Center

    Davidson, Philip M.

    This study is a preliminary attempt to characterize the development of students' conceptions of education in a comprehensive fashion. The participants were recruited from a middle class suburban school district in Michigan. Seventy students in grades 3, 6, 9, and 12 were interviewed about several issues related to each of the following: (1) the…

  4. [On the concept of lucidity].

    PubMed

    Martínez, Daniel R

    2014-01-01

    Kraepelin's concept of clarity of awareness (lucidity) had a stable signification during more than hundred years. It is the basis of most of current theories of disturbed consciousness. However, two alternative definitions that arise in Buenos Aires produce confusion due to their conceptual overlap. We discuss these definitions and propose a classification of disorders of consciousness that rely on traditional point of view.

  5. Logistic Regression: Concept and Application

    ERIC Educational Resources Information Center

    Cokluk, Omay

    2010-01-01

    The main focus of logistic regression analysis is classification of individuals in different groups. The aim of the present study is to explain basic concepts and processes of binary logistic regression analysis intended to determine the combination of independent variables which best explain the membership in certain groups called dichotomous…

  6. Understanding Electrochemistry: Some Distinctive Concepts.

    ERIC Educational Resources Information Center

    Faulkner, Larry R.

    1983-01-01

    Addresses concepts about electrochemical systems that cause confusion among those new to the subject. The goal is to synthesize an understanding of the heterogeneity of an electrochemical system and a chemical sense for the important electrochemical variables of potential, current, and charge. (JN)

  7. Basic Concepts of CNS Development.

    ERIC Educational Resources Information Center

    Nowakowski, R. S.

    1987-01-01

    The goals of this review are to: (1) provide a set of concepts to aid in the understanding of complex processes which occur during central nervous system (CNS) development; (2) illustrate how they contribute to our knowlege of adult brain anatomy; and (3) delineate how modifications of normal developmental processes may affect the structure and…

  8. Concepts & Procedures. [SITE 2002 Section].

    ERIC Educational Resources Information Center

    Sarner, Ronald, Ed.; Mullick, Rosemary J., Ed.; Bauder, Deborah Y., Ed.

    This document contains the following full and short papers on concepts and procedures from the SITE (Society for Information Technology & Teacher Education) 2002 conference: "Exploring Minds Network" (Marino C. Alvarez and others); "Learning Communities: A Kaleidoscope of Ecological Designs" (Alain Breuleux and others);…

  9. Concepts & Procedures. [SITE 2001 Section].

    ERIC Educational Resources Information Center

    Bauder, Deborah Y., Ed.; Mullick, Rosemary, Ed.; Sarner, Ronald, Ed.

    This document contains the following papers on concepts and procedures from the SITE (Society for Information Technology & Teacher Education) 2001 conference: "Using School District Standards To Develop Thematic Lessons for Electronic Portfolios" (Cindy L. Anderson and others); "Using Adobe Acrobat for Electronic Portfolio…

  10. TODAY'S CONCEPTS IN SCHOOL LIGHTING.

    ERIC Educational Resources Information Center

    GIBSON, CHARLES D.

    SEVERAL SCHOOL LIGHTING CONCEPTS ARE PRESENTED IN THIS ARTICLE. THEY ARE AS FOLLOWS--(1) NONCAPTIVE RESEARCH SHOULD BE CARRIED ON THROUGH COORDINATION BETWEEN RESEARCH AND APPLICATION SEGMENTS OF THE LIGHTING INDUSTRY, (2) COMMUNICATION AND JOINT EFFORT SHOULD PROVIDE THAT MAJOR AGENCIES INVOLVED IN THE APPLICATION OF LIGHTING DESIGN CRITERIA HAVE…

  11. The Theory of Figural Concepts.

    ERIC Educational Resources Information Center

    Fischbein, Efraim

    1993-01-01

    The main thesis of the paper is that geometry deals with mental entities (the so-called geometrical figures) which possess simultaneously conceptual and figural characters. The paper analyzes the internal tensions which may arise in figural concepts because of their double nature, developmental aspects, and didactical implications. (Author/MDH)

  12. California School Energy Concepts, 1978.

    ERIC Educational Resources Information Center

    Askin, Ralph J.; And Others

    This publication is one of the major efforts of a project designed to promote energy conservation in California schools. Suggestions are provided that can be adapted at individual school facilities to reduce energy consumption. The guide also focuses on the major concepts of the new state standards for energy conservation for new nonresidential…

  13. Two Concepts for Deployable Trusses

    NASA Technical Reports Server (NTRS)

    Renfro, John W.

    2010-01-01

    Two concepts that could be applied separately or together have been suggested to enhance the utility of deployable truss structures. The concepts were intended originally for application to a truss structure to be folded for compact stowage during transport and subsequently deployed in outer space. The concepts may also be applicable, with some limitations, to deployable truss structures designed to be used on Earth. The first concept involves a combination of features that would help to maximize reliability of a structure while minimizing its overall mass, the complexity of its deployment system, and the expenditure of energy for deployment. The deployment system would be integrated into the truss: some of the truss members would contain folding/unfolding-detent mechanisms similar to those in umbrellas; other truss members would contain shape-memory-alloy (SMA) coil actuators (see Figure 1). Upon exposure to sunlight, the SMA actuators would be heated above their transition temperature, causing them to extend to their deployment lengths. The extension of the actuators would cause the structure to unfold and, upon completion of unfolding, the umbrellalike mechanisms would lock the unfolded truss in the fully deployed configuration. The use of solar heating to drive deployment would eliminate the need to carry a deployment power source. The actuation scheme would offer high reliability in that the truss geometry would be such that deployment could be completed even if all actuators were not functioning. Of course, in designing for operation in normal Earth gravitation, it would be necessary to ensure that the SMA actuators could apply forces large enough to overcome the deploymentresisting forces attributable to the weights of the members. The second concept is that of an improved design for the joints in folding members. Before describing this design,

  14. Advanced Turbofan Duct Liner Concepts

    NASA Technical Reports Server (NTRS)

    Bielak, Gerald W.; Premo, John W.; Hersh, Alan S.

    1999-01-01

    The Advanced Subsonic Technology Noise Reduction Program goal is to reduce aircraft noise by 10 EPNdB by the year 2000 relative, to 1992 technology. The improvement goal for nacelle attenuation is 25% relative to 1992 technology by 1997 and 50% by 2000. The Advanced Turbofan Duct Liner Concepts Task work by Boeing presented in this document was in support of these goals. The basis for the technical approach was a Boeing study conducted in 1993-94 under NASA/FAA contract NAS1-19349, Task 6, investigating broadband acoustic liner concepts. As a result of this work, it was recommended that linear double layer, linear and perforate triple layer, parallel element, and bulk absorber liners be further investigated to improve nacelle attenuations. NASA LaRC also suggested that "adaptive" liner concepts that would allow "in-situ" acoustic impedance control also be considered. As a result, bias flow and high-temperature liner concepts were also added to the investigation. The major conclusion from the above studies is that improvements in nacelle liner average acoustic impedance characteristics alone will not result in 25% increased nacelle noise reduction relative to 1992 technology. Nacelle design advancements currently being developed by Boeing are expected to add 20-40% more acoustic lining to hardwall regions in current inlets, which is predicted to result in and additional 40-80% attenuation improvement. Similar advancements are expected to allow 10-30% more acoustic lining in current fan ducts with 10-30% more attenuation expected. In addition, Boeing is currently developing a scarf inlet concept which is expected to give an additional 40-80% attenuation improvement for equivalent lining areas.

  15. Concept Mapping and the Cartography of Cognition.

    ERIC Educational Resources Information Center

    Wandersee, James H.

    1990-01-01

    Because concept maps are designed to find out what the learner knows about a subject and are, in effect, maps of cognition, this article synthesizes relevant facts, concepts, and principles from cartography and applies them to concept mapping. The metaphor of the map and its applicability for representing scientific concepts are discussed. (PR)

  16. On the Concept Image of Complex Numbers

    ERIC Educational Resources Information Center

    Nordlander, Maria Cortas; Nordlander, Edvard

    2012-01-01

    A study of how Swedish students understand the concept of complex numbers was performed. A questionnaire was issued reflecting the student view of own perception. Obtained answers show a variety of concept images describing how students adopt the concept of complex numbers. These concept images are classified into four categories in order to…

  17. Using Concept Mapping in the Biology Classroom.

    ERIC Educational Resources Information Center

    Donovan, Edward P.

    Concept mapping, a technique based on David Ausubel's theory of meaningful learning, involves the organization of concepts into an hierarchical arrangement. Suggestions for incorporating this learning strategy into the biology classroom are presented and discussed. Steps in concept mapping include: (1) identifying important concepts in the study…

  18. Conceptual Learning and the Self-Concept.

    ERIC Educational Resources Information Center

    Meinke, Dean L.

    Using subjects classified on the basis of positive and less positive self-concepts, this study investigates the effects of instructions, a principle, and practice with four concept-attainment problems on the efficiency of the attainment of concepts among subjects. The findings indicate the subjects with more positive self-concepts attain abstract…

  19. THE THEME-CONCEPT UNIT IN LITERATURE.

    ERIC Educational Resources Information Center

    HILLOCKS, GEORGE, JR.

    A SUGGESTED UNIT FRAMEWORK WAS DEVELOPED AS A METHOD OF TEACHING SEVENTH-GRADE LITERATURE AT EUCLID CENTRAL JUNIOR HIGH SCHOOL IN EUCLID, OHIO. THE UNIT WAS DIVIDED INTO SIX MAJOR SECTIONS--(1) DEVELOPMENT OF THE CONCEPT, (2) APPLICATION OF THE CONCEPT UNDER THE GUIDANCE OF A TEACHER, (3) REVISION OF THE CONCEPT, (4) APPLICATION OF THE CONCEPT BY…

  20. Bottleneck Concepts in Psychology: Exploratory First Steps

    ERIC Educational Resources Information Center

    Gurung, Regan A. R.; Landrum, R. Eric

    2013-01-01

    The authors take an initial step in identifying potential bottleneck concepts in psychology, that is, concepts that are deceptively difficult, perhaps due to student overconfidence. In order to first identify bottleneck concepts, faculty (n = 65) rated the difficulty of 91 psychological concepts from across the discipline. Students (n = 35) rated…

  1. Cognitive Architecture of Common and Scientific Concepts

    NASA Astrophysics Data System (ADS)

    Tarábek, Paul

    2010-07-01

    The cognitive architecture of concept is a specific structure consisting of the concept core, concept periphery, the semantic frame as the meaning and the sense of the concept, and the relations among all components of this structure. The model of the cognitive architecture of scientific and common concepts is a conceptual meta-model built upon Vygotsky's concept theory, Fillmore's semantic frame, semantic triangle, on widespread ideas of the structuring of conceptual systems, and the Hestenes' Modeling Theory. The method of semantic mapping of concepts flowing from the model is designed.

  2. Identifying and Overcoming Threshold Concepts and Conceptions: Introducing a Conception-Focused Curriculum to Course Design

    ERIC Educational Resources Information Center

    Burch, Gerald F.; Burch, Jana J.; Bradley, Thomas P.; Heller, Nathan A.

    2015-01-01

    Educators have been challenged to identify threshold concepts and develop transformed students. This stands in stark contrast to many curriculum design and delivery models that currently view students as repositories of knowledge. In this article, we argue that educators can reach both goals, identify stumbling blocks and transforming students,…

  3. Pioneering Concepts of Planetary Habitability

    NASA Astrophysics Data System (ADS)

    Raulin Cerceau, Florence

    Famous astronomers such as Richard A. Proctor (1837-1888), Jules Janssen (1824-1907), and Camille Flammarion (1842-1925) studied the concept of planetary habitability a century before this concept was updated in the context of the recent discoveries of exoplanets and the development of planetary exploration in the solar system. They independently studied the conditions required for other planets to be inhabited, and these considerations led them to specify the term "habitability." Naturally, the planet Mars was at the heart of the discussion. Our neighboring planet, regarded as a sister planet of Earth, looked like a remarkable abode for life. During the second part of the nineteenth century, the possibility of Martian intelligent life was intensively debated, and hopes were still ardent to identify a kind of vegetation specific to the red planet. In such a context, the question of Mars' habitability seemed to be very valuable, especially when studying hypothetical Martian vegetation. At the dawn of the Space Age, German-born physician and pioneer of space medicine Hubertus Strughold (1898-1987) proposed in the book The Green and Red Planet: A Physiological Study of the Possibility of Life on Mars (1954) to examine the planets of the solar system through a "planetary ecology." This innovative notion, which led to a fresh view of the concept of habitability, was supposed to designate a new field involving biology: "the science of planets as an environment for life" (Strughold 1954). This notion was very close to the concept of habitability earlier designated by our nineteenth-century pioneers. Strughold also coined the term "ecosphere" to name the region surrounding a star where conditions allowed life-bearing planets to exist. We highlight in this chapter the historical aspects of the emergence of the (modern) concept of habitability. We will consider the different formulations proposed by the pioneers, and we will see in what way it can be similar to our

  4. Transportation System Concept of Operations

    SciTech Connect

    N. Slater-Thompson

    2006-08-16

    The Nuclear Waste Policy Act of 1982 (NWPA), as amended, authorized the DOE to develop and manage a Federal system for the disposal of SNF and HLW. OCRWM was created to manage acceptance and disposal of SNF and HLW in a manner that protects public health, safety, and the environment; enhances national and energy security; and merits public confidence. This responsibility includes managing the transportation of SNF and HLW from origin sites to the Repository for disposal. The Transportation System Concept of Operations is the core high-level OCRWM document written to describe the Transportation System integrated design and present the vision, mission, and goals for Transportation System operations. By defining the functions, processes, and critical interfaces of this system early in the system development phase, programmatic risks are minimized, system costs are contained, and system operations are better managed, safer, and more secure. This document also facilitates discussions and understanding among parties responsible for the design, development, and operation of the Transportation System. Such understanding is important for the timely development of system requirements and identification of system interfaces. Information provided in the Transportation System Concept of Operations includes: the functions and key components of the Transportation System; system component interactions; flows of information within the system; the general operating sequences; and the internal and external factors affecting transportation operations. The Transportation System Concept of Operations reflects OCRWM's overall waste management system policies and mission objectives, and as such provides a description of the preferred state of system operation. The description of general Transportation System operating functions in the Transportation System Concept of Operations is the first step in the OCRWM systems engineering process, establishing the starting point for the lower level

  5. Emerging concepts of brain function.

    PubMed

    Bach-Y-Rita, Paul

    2005-06-01

    For over 40 years, since I first obtained evidence for nonsynaptic diffusion neurotransmission (most scientists call it Volume Transmission), I have been convinced that we scientists were ignoring organizational dynamics other than the mechanistic synaptic organization of the brain. For many years it was an uneasy feeling, since I was aware there are so many avenues to explore in brain function. I have wondered how much we scientists have ignored, in our quest to understand how the brain really works, due to our efforts to "be scientific". In addition to the difficulty of understanding how the brain functions, how could we even begin to explore the human experience? In this paper I will first discuss some emerging concepts of brain function. I will then comment on the development of concepts that have been a part of my own research experience.

  6. Bistatic SAR: Proof of Concept.

    SciTech Connect

    Yocky, David A.; Doren, Neall E.; Bacon, Terry A.; Wahl, Daniel E.; Eichel, Paul H.; Jakowatz, Charles V,; Delaplain, Gilbert G.; Dubbert, Dale F.; Tise, Bertice L.; White, Kyle R.

    2014-10-01

    Typical synthetic aperture RADAR (SAR) imaging employs a co-located RADAR transmitter and receiver. Bistatic SAR imaging separates the transmitter and receiver locations. A bistatic SAR configuration allows for the transmitter and receiver(s) to be in a variety of geometric alignments. Sandia National Laboratories (SNL) / New Mexico proposed the deployment of a ground-based RADAR receiver. This RADAR receiver was coupled with the capability of digitizing and recording the signal collected. SNL proposed the possibility of creating an image of targets the illuminating SAR observes. This document describes the developed hardware, software, bistatic SAR configuration, and its deployment to test the concept of a ground-based bistatic SAR. In the proof-of-concept experiments herein, the RADAR transmitter will be a commercial SAR satellite and the RADAR receiver will be deployed at ground level, observing and capturing RADAR ground/targets illuminated by the satellite system.

  7. Modular hydrodam: concept definition study

    SciTech Connect

    Not Available

    1981-07-01

    The purpose of this investigation was to explore the potential for developing economical new ultra low-head (6 to 10 ft) sites using an innovative concept known as the Modular Hydrodam (MH). This concept combines the benefits of shop fabrication, installation of equipment in truck transportable, waterproof power modules, and prefabricated gate sections that can be located between the power modules. The size and weight of the power module permits it to be fully assembled and checked out in the manufacturer's shop. The module can then be broken down into four pieces and shipped by truck to the site. Once in place, concrete ballast will be added, as necessary, to prevent flotation. The following aspects were investigated: tubular and cross flow turbines; modularized components; the use of a cable support system for horizontal stability of the dam and powerhouse; and construction in the wet as well as in the dry.

  8. Psychosocial Concepts in Rheumatoid Arthritis

    PubMed Central

    McGillivray, Donald C.

    1973-01-01

    This article reviews and tabulates some of the current concepts of the role of psychosocial factors in rheumatoid arthritis (RA). Concepts prevalent during the 1950's are listed followed by discussion of some of the variable factors that complicate studies in this field. Studies are then cited which lead to the following conclusions: 1. Patients with RA tend to have certain personality characteristics, such as depression, rigidity, dependency, neurotic response patterns, emotional instability, feelings of guilt and low ego strength. 2. These are not specific to RA. 3. They may well be sequelae of the disease rather than pre-morbid features. 4. There is no clear evidence as to the role of psychological stress in causing or activating RA. 5. Personality factors have an influence on the course of the disease. PMID:20468900

  9. MCCB warm adjustment testing concept

    NASA Astrophysics Data System (ADS)

    Erdei, Z.; Horgos, M.; Grib, A.; Preradović, D. M.; Rodic, V.

    2016-08-01

    This paper presents an experimental investigation in to operating of thermal protection device behavior from an MCCB (Molded Case Circuit Breaker). One of the main functions of the circuit breaker is to assure protection for the circuits where mounted in for possible overloads of the circuit. The tripping mechanism for the overload protection is based on a bimetal movement during a specific time frame. This movement needs to be controlled and as a solution to control this movement we choose the warm adjustment concept. This concept is meant to improve process capability control and final output. The warm adjustment device design will create a unique adjustment of the bimetal position for each individual breaker, determined when the testing current will flow thru a phase which needs to trip in a certain amount of time. This time is predetermined due to scientific calculation for all standard types of amperages and complies with the IEC 60497 standard requirements.

  10. Perspectives on culture and concepts.

    PubMed

    ojalehto, Bethany l; Medin, Douglas L

    2015-01-03

    The well-respected tradition of research on concepts uses cross-cultural comparisons to explore which aspects of conceptual behavior are universal versus culturally variable. This work continues, but it is being supplemented by intensified efforts to study how conceptual systems and cultural systems interact to modify and support each other. For example, cultural studies within the framework of domain specificity (e.g., folkphysics, folkpsychology, folkbiology) are beginning to query the domains themselves and offer alternative organizing principles (e.g., folksociology, folkecology). Findings highlight the multifaceted nature of both concepts and culture: Individuals adopt distinct conceptual construals in accordance with culturally infused systems such as language and discourse, knowledge and beliefs, and epistemological orientations. This picture complicates questions about cognitive universality or variability, suggesting that researchers may productively adopt a systems-level approach to conceptual organization and cultural epistemologies. Related implications for diversity in cognitive science are discussed.

  11. Is codependency a meaningful concept?

    PubMed

    Stafford, L L

    2001-01-01

    The concept of condependency has achieved a prominent place in the psychiatric, psychological, and addiction literature in a remarkably short period of time. Although the term was first developed in the substance abuse treatment arena, specifically referring to the wives of men who abuse alcohol, codependency has more recently been used almost generically to describe a dysfunctional style of relating to others (Irwin, 1995). The manner in which definitions of codependency have become increasingly inclusive are probably related to continuing input from the both the fashionable self-help movement and from some psychiatric perspectives. The purpose of this article is to review proposed definitions of codependency, discuss issues related to the validity of the codependency construct, and summarize efforts aimed at producing instruments to measure codependency. Additionally, I will address implications of this concept as related to psychiatric nursing education, practice, and research.

  12. Basic concepts in mechanical ventilation.

    PubMed

    Carbery, Catherine

    2008-03-01

    Mechanical ventilatory support is a major component of the clinical management of critically ill patients admitted into intensive care. Closely linked with the developments within critical care medicine, the use of ventilatory support has been increasing since the polio epidemics in the 1950s (Lassen 1953). Initially used to provide controlled mandatory ventilation, today with advances in technology, most mechanical ventilators are triggered by the patient, increasing the awareness of the complexity of patient/ventilator interaction (Tobin 1994). Though ventilator appearance and design may have changed quite significantly and the variety of options for support extensive, the basic concepts of mechanical ventilatory support of the critically ill patient remains unchanged. This paper aims to outline these concepts so as to gain a better understanding of mechanical ventilatory support.

  13. Ingredients for Life (Artist's Concept)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1: Artist's Conception Symbolically Represents Complex Organic Molecules

    This artist's conception symbolically represents complex organic molecules, known as polycyclic aromatic hydrocarbons, seen in the early universe. These large molecules, comprised of carbon and hydrogen, are considered among the building blocks of life.

    NASA's Spitzer Space Telescope is the first telescope to see polycyclic aromatic hydrocarbons so early -- 10 billion years further back in time than seen previously. Spitzer detected these molecules in galaxies when our universe was one-fourth of its current age of about 14 billion years.

    These complex molecules are very common on Earth. They form any time carbon-based materials are not burned completely. They can be found in sooty exhaust from cars and airplanes, and in charcoal broiled hamburgers and burnt toast.

    Polycyclic aromatic hydrocarbons are pervasive in galaxies like our own Milky Way, and play a significant role in star and planet formation.

  14. Concepts of renormalization in physics.

    PubMed

    Alexandre, Jean

    2005-01-01

    A non technical introduction to the concept of renormalization is given, with an emphasis on the energy scale dependence in the description of a physical system. We first describe the idea of scale dependence in the study of a ferromagnetic phase transition, and then show how similar ideas appear in particle physics. This short review is written for non-particle physicists and/or students aiming at studying particle physics.

  15. Concepts in human biological rhythms

    PubMed Central

    Reinberg, Alain; Ashkenazi, Israel

    2003-01-01

    Biological rhythms and their temporal organization are adaptive phenomena to periodic changes in environmental factors linked to the earth's rotation on its axis and around the sun. Experimental data from the plant and animal kingdoms have led to many models and concepts related to biological clocks that help describe and understand the mechanisms of these changes. Many of the prevailing concepts apply to all organisms, but most of the experimental data are insufficient to explain the dynamics of human biological clocks. This review presents phenomena thai are mainly characteristic ofand unique to - human chronobiology, and which cannot be fully explained by concepts and models drawn from laboratory experiments. We deal with the functional advantages of the human temporal organization and the problem of desynchronization, with special reference to the period (τ) of the circadian rhythm and its interindividual and intraindividual variability. We describe the differences between right- and left-hand rhythms suggesting the existence of different biological clocks in the right and left cortices, Desynchronization of rhythms is rather frequent (one example is night shift workers). In some individuals, desynchronization causes no clinical symptoms and we propose the concept of “allochronism” to designate a variant of the human temporal organization with no pathological implications. We restrict the term “dyschronism” to changes or alterations in temporal organization associated with a set of symptoms similar to those observed in subjects intolerant to shift work, eg, persisting fatigue and mood and sleep alterations. Many diseases involve chronic deprivation of sleep at night and constitute conditions mimicking thai of night shift workers who are intolerant to desynchronization. We also present a genetic model (the dian-circadian model) to explain interindividual differences in the period of biological rhythms in certain conditions. PMID:22033796

  16. Advanced Concepts for Sea Control,

    DTIC Science & Technology

    1977-11-01

    technology sea control missions, 1,000 tonnes to advances occur, and the threat needs 25,000 tonnes would be representative change, a proper balance can be...sea loiter aircraft, conventional subcavitating fully-sub- utilizing the stopped rotor concept; merged foils, thus providing a very a small sea...augmentation engines have been platform characteristics at conventional moved from their overhung location to a displacement ship speeds but at a re- . place

  17. New solid armature design concept

    SciTech Connect

    Del Vecchio, R.M. )

    1991-01-01

    Solid armatures in railgun applications experience extreme mechanical, thermal, and electromagnetic conditions. They must be able to survive a launch without undue bore damage and yet have as small a mass as possible. In this paper, a new solid armature concept is presented, some of the factors influencing its design are examined and some relationships are established among the physical parameters which characterize its operation.

  18. A Concept of Corporate Memory

    DTIC Science & Technology

    1979-05-17

    CONTRACT OR GRANT NUMBER^*; N00014-75.-C-0462. ». PERFORMING ORGANIZATION NAME AND ADDRESS Department of Decision Sciences ’ The Wharton School...Decision Sciences The Wharton School University of Pennsylvania Philadelphia, PA 19104 "Tftis foi P^ut- -^ urUlnil This paper will be presented at the...Philadelphia PA 19104 A CONCEPT OF CORPORATE MEMORY Howard L. Morgan and David J. Root Dept. of Decision Sciences , The Whart’on School Abstract An

  19. GRC RBCC Concept Multidisciplinary Analysis

    NASA Technical Reports Server (NTRS)

    Suresh, Ambady

    2001-01-01

    This report outlines the GRC RBCC Concept for Multidisciplinary Analysis. The multidisciplinary coupling procedure is presented, along with technique validations and axisymmetric multidisciplinary inlet and structural results. The NPSS (Numerical Propulsion System Simulation) test bed developments and code parallelization are also presented. These include milestones and accomplishments, a discussion of running R4 fan application on the PII cluster as compared to other platforms, and the National Combustor Code speedup.

  20. The concept of bond order

    NASA Astrophysics Data System (ADS)

    Elliott, Robert J.; Richards, W. Graham

    A method for obtaining precise charge densities in defined regions of space from ab initio molecular wavefunctions is employed to place the concept of bond order on a firm theoretical footing. The bond orders obtained for carbon—carbon bonds in a range of organic compounds are assessed: those for buta-1,3-diene confirm that it consists of essentially localised double and single bonds.

  1. Anticipatory Grief: A Mere Concept?

    PubMed

    Moon, Paul J

    2016-06-01

    Anticipatory grief (AG) has been studied, debated, and written about for several decades. This type of grief is also recognized in hospice and palliative care (HPC). The question, however, is whether the reality of AG is sufficiently upheld by professionals at the point of concrete service delivery. In other words, is AG a mere concept or is everyday practice of HPC duly informed of AG as evidenced by the resulting care delivery?

  2. [Basic concepts in biomedical ethics].

    PubMed

    Arn, Christof

    2009-08-01

    Starting with a complex clinical situation we introduce basic concepts of clinical ethics. We explain why well-defined terms are needed and demonstrate how these terms can be used as practical tools for approaching and resolving ethical dilemmas in a professional decision-making process. It will be outlined how the use of these terms may contribute to the understanding of the ways in which moral values are perceived and communication skills can be improved.

  3. Therapeutic cloning: concepts and practicalities.

    PubMed

    Colman, A; Kind, A

    2000-05-01

    The concept of using embryonic stem (ES) cells as a source of multiple cell types for use in tissue repair has existed for approximately 20 years. Recent breakthroughs in somatic nuclear transfer and human ES cell derivation have produced a flurry of new activity in this area, with the recognition that ES cell lines that are customized and genetically identical to those of the patient are a distinct possibility. This article examines the background of and prospects for these exciting new developments.

  4. Alternative Terrain Following System Concepts,

    DTIC Science & Technology

    1977-11-01

    inertial altitude rate command in response to errors in terrain clearance altitude. This command is limited and summed with the actual rate of change of...altitude rate command in response to errors in the clearance altitude. This command is limited and summed with the rate of change of clearance...altitude. The normal acceleration command is generated in response to errors in the rate of change of terrain clearance. System Concept B describes a

  5. Species concepts and species delimitation.

    PubMed

    De Queiroz, Kevin

    2007-12-01

    The issue of species delimitation has long been confused with that of species conceptualization, leading to a half century of controversy concerning both the definition of the species category and methods for inferring the boundaries and numbers of species. Alternative species concepts agree in treating existence as a separately evolving metapopulation lineage as the primary defining property of the species category, but they disagree in adopting different properties acquired by lineages during the course of divergence (e.g., intrinsic reproductive isolation, diagnosability, monophyly) as secondary defining properties (secondary species criteria). A unified species concept can be achieved by treating existence as a separately evolving metapopulation lineage as the only necessary property of species and the former secondary species criteria as different lines of evidence (operational criteria) relevant to assessing lineage separation. This unified concept of species has several consequences for species delimitation, including the following: First, the issues of species conceptualization and species delimitation are clearly separated; the former secondary species criteria are no longer considered relevant to species conceptualization but only to species delimitation. Second, all of the properties formerly treated as secondary species criteria are relevant to species delimitation to the extent that they provide evidence of lineage separation. Third, the presence of any one of the properties (if appropriately interpreted) is evidence for the existence of a species, though more properties and thus more lines of evidence are associated with a higher degree of corroboration. Fourth, and perhaps most significantly, a unified species concept shifts emphasis away from the traditional species criteria, encouraging biologists to develop new methods of species delimitation that are not tied to those properties.

  6. Modelling Accident Tolerant Fuel Concepts

    SciTech Connect

    Hales, Jason Dean; Gamble, Kyle Allan Lawrence

    2016-05-01

    The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. The United States Department of Energy (DOE) through its Nuclear Energy Advanced Modeling and Simulation (NEAMS) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is a three-year project to perform research on two accident tolerant concepts. The final outcome of the ATF HIP will be an in-depth report to the DOE Advanced Fuels Campaign (AFC) giving a recommendation on whether either of the two concepts should be included in their lead test assembly scheduled for placement into a commercial reactor in 2022. The two ATF concepts under investigation in the HIP are uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (Idaho National Laboratory, Los Alamos National Laboratory, and Argonne National Laboratory), a comprehensive multiscale approach to modeling is being used that includes atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. Model development and fuel performance analysis are critical since a full suite of experimental studies will not be complete before AFC must prioritize concepts for focused development. In this paper, we present simulations of the two proposed accident tolerance fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. Sensitivity analyses are completed using Sandia National Laboratories’ Dakota software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). We also outline the multiscale modelling approach being employed. Considerable additional work is required prior to preparing the recommendation report for the Advanced

  7. Food insecurity: A concept analysis

    PubMed Central

    Schroeder, Krista; Smaldone, Arlene

    2015-01-01

    Aim To report an analysis of the concept of food insecurity, in order to 1) propose a theoretical model of food insecurity useful to nursing and 2) discuss its implications for nursing practice, nursing research, and health promotion. Background Forty eight million Americans are food insecure. As food insecurity is associated with multiple negative health effects, nursing intervention is warranted. Design Concept Analysis Data sources A literature search was conducted in May 2014 in Scopus and MEDLINE using the exploded term “food insecur*.” No year limit was placed. Government websites and popular media were searched to ensure a full understanding of the concept. Review Methods Iterative analysis, using the Walker and Avant method Results Food insecurity is defined by uncertain ability or inability to procure food, inability to procure enough food, being unable to live a healthy life, and feeling unsatisfied. A proposed theoretical model of food insecurity, adapted from the Socio-Ecological Model, identifies three layers of food insecurity (individual, community, society), with potential for nursing impact at each level. Conclusion Nurses must work to fight food insecurity. There exists a potential for nursing impact that is currently unrealized. Nursing impact can be guided by a new conceptual model, Food Insecurity within the Nursing Paradigm. PMID:25612146

  8. [Pre-conception sex selection].

    PubMed

    Julesz, Máté

    2014-11-16

    According to Article 14 of the Oviedo Convention on Human Rights and Biomedicine of the Council of Europe, the use of techniques of medically assisted procreation shall not be allowed for the purpose of choosing the sex of a future child, unless serious hereditary sex-related disease is to be avoided. In Israel and the United States of America, pre-conception sex selection for the purpose of family balancing is legal. The European health culture does not regard reproductive justice as part of social justice. From this aspect, the situation is very similar in China and India. Reproductive liberty is opposed by the Catholic Church, too. According to the Catholic Church, medical grounds may not justify pre-conception sex selection, though being bioethically less harmful than family balancing for social reasons. In Hungary, according to Section 170 of the Criminal Code, pre-conception sex selection for the purpose of family balancing constitutes a crime. At present, the Hungarian legislation is in full harmony with the Oviedo Convention, enacted in Hungary in 2002.

  9. Human Error: A Concept Analysis

    NASA Technical Reports Server (NTRS)

    Hansen, Frederick D.

    2007-01-01

    Human error is the subject of research in almost every industry and profession of our times. This term is part of our daily language and intuitively understood by most people however, it would be premature to assume that everyone's understanding of human error s the same. For example, human error is used to describe the outcome or consequence of human action, the causal factor of an accident, deliberate violations,a nd the actual action taken by a human being. As a result, researchers rarely agree on the either a specific definition or how to prevent human error. The purpose of this article is to explore the specific concept of human error using Concept Analysis as described by Walker and Avant (1995). The concept of human error is examined as currently used in the literature of a variety of industries and professions. Defining attributes and examples of model, borderline, and contrary cases are described. The antecedents and consequences of human error are also discussed and a definition of human error is offered.

  10. Key Concepts in Microbial Oceanography

    NASA Astrophysics Data System (ADS)

    Bruno, B. C.; Achilles, K.; Walker, G.; Weersing, K.; Team, A

    2008-12-01

    The Center for Microbial Oceanography: Research and Education (C-MORE) is a multi-institution Science and Technology Center, established by the National Science Foundation in 2006. C-MORE's research mission is to facilitate a more comprehensive understanding of the diverse assemblages of microorganisms in the sea, ranging from the genetic basis of marine microbial biogeochemistry including the metabolic regulation and environmental controls of gene expression, to the processes that underpin the fluxes of carbon, related bioelements, and energy in the marine environment. The C-MORE education and outreach program is focused on increasing scientific literacy in microbial oceanography among students, educators, and the general public. A first step toward this goal is defining the key concepts that constitute microbial oceanography. After lengthy discussions with scientists and educators, both within and outside C-MORE, we have arrived at six key concepts: 1) Marine microbes are very small and have been around for a long time; 2) Life on Earth could not exist without microbes; 3) Most marine microbes are beneficial; 4) Microbes are everywhere: they are extremely abundant and diverse; 5) Microbes significantly impact our global climate; and 6) There are new discoveries every day in the field of microbial oceanography. A C-MORE-produced brochure on these six key concepts will be distributed at the meeting. Advanced copies may be requested by email or downloaded from the C-MORE web site(http://cmore.soest.hawaii.edu/downloads/MO_key_concepts_hi-res.pdf). This brochure also includes information on career pathways in microbial oceanography, with the aim of broadening participation in the field. C-MORE is eager to work in partnership to incorporate these key concepts into other science literacy publications, particularly those involving ocean and climate literacy. We thank the following contributors and reviewers: P Chisholm, A Dolberry, and A Thompson (MIT); N Lawrence

  11. Nomadic concepts in the history of biology.

    PubMed

    Surman, Jan; Stráner, Katalin; Haslinger, Peter

    2014-12-01

    The history of scientific concepts has firmly settled among the instruments of historical inquiry. In our section we approach concepts from the perspective of nomadic concepts (Isabelle Stengers). Instead of following the evolution of concepts within one disciplinary network, we see them as subject to constant reification and change while crossing and turning across disciplines and non-scientific domains. This introduction argues that understanding modern biology is not possible without taking into account the constant transfers and translations that affected concepts. We argue that this approach does not only engage with nomadism between disciplines and non-scientific domains, but reflects on and involves the metaphoric value of concepts as well.

  12. Teachers' Concepts of Reading, Reading Concepts Communicated during Instruction, and Students' Concepts of Reading. Research Series No. 190.

    ERIC Educational Resources Information Center

    Book, Cassandra; And Others

    As part of the Teacher Explanation Project (TEP), a study examined the relationships among third-grade teachers' concepts of reading, the concepts of reading they communicated during instruction to low-level readers, and the students' concepts of reading. Subjects, 20 third-grade teachers, participated in the yearlong TEP study conducted in an…

  13. [Concept analysis of reflective thinking].

    PubMed

    Van Vuuren, M; Botes, A

    1999-09-01

    The nursing practice is described as a scientific practice, but also as a practice where caring is important. The purpose of nursing education is to provide competent nursing practitioners. This implies that future practitioners must have both critical analytical thinking abilities, as well as empathy and moral values. Reflective thinking could probably accommodate these thinking skills. It seems that the facilitation of reflective thinking skills is essential in nursing education. The research question that is relevant in this context is: "What is reflective thinking?" The purpose of this article is to report on the concept analysis of reflective thinking and in particular on the connotative meaning (critical attributes) thereof. The method used to perform the concept analysis is based on the original method of Wilson (1987) as described by Walker & Avant (1995). As part of the concept analysis the connotations (critical attributes) are identified, reduced and organized into three categories, namely pre-requisites, processes and outcomes. A model case is described which confirms the essential critical attributes of reflective thinking. Finally a theoretical definition of reflective thinking is derived and reads as follows: Reflective thinking is a cyclic, hierarchical and interactive construction process. It is initiated, extended and continued because of personal cognitive-affective interaction (individual dimension) as well as interaction with the social environment (social dimension). to realize reflective thinking, a level of internalization on the cognitive and affective domain is required. The result of reflective thinking is a integrated framework of knowledge (meaningful learning) and a internalized value system providing a new perspective on and better understanding of a problem. Reflective thinking further leads to more effective decision making- and problem solving skills.

  14. Advanced fusion concepts: project summaries

    SciTech Connect

    1980-12-01

    This report contains descriptions of the activities of all the projects supported by the Advanced Fusion Concepts Branch of the Office of Fusion Energy, US Department of Energy. These descriptions are project summaries of each of the individual projects, and contain the following: title, principle investigators, funding levels, purpose, approach, progress, plans, milestones, graduate students, graduates, other professional staff, and recent publications. Information is given for each of the following programs: (1) reverse-field pinch, (2) compact toroid, (3) alternate fuel/multipoles, (4) stellarator/torsatron, (5) linear magnetic fusion, (6) liners, and (7) Tormac. (MOW)

  15. Basic Concepts of Positional Astronomy

    NASA Astrophysics Data System (ADS)

    Ruggles, Clive L. N.

    This article describes and defines a number of basic concepts that are commonly used in archaeoastronomy and ethnoastronomy, sometimes in particular ways, and attempts to clarify some of the issues of confusion that frequently arise. It is aimed primarily at archaeologists and ethnographers entering or exploring the field and emphasizes the broad principles that are generally of importance to them, while trying to avoid unnecessary complications as well as technical details. It is not aimed at those studying historical sources from antiquity onward, who need a more sophisticated knowledge of positional astronomy, mathematically formulated. Further detail can be found in a variety of sources, including a number aimed specifically at archaeoastronomers.

  16. Long life valve design concepts

    NASA Technical Reports Server (NTRS)

    Jones, J. R.; Hall, A. H., Jr.

    1975-01-01

    Valve concept evaluation, final candidate selection, design, manufacture, and demonstration testing of a pneumatically actuated 10-inch hybrid poppet butterfly shutoff valve are presented. Conclusions and recommendations regarding those valve characteristics and features which would serve to guide in the formulation of future valve procurements are discussed. The pertinent design goals were temperature range of plus 200 to minus 423 F, valve inlet pressure 35 psia, actuation pressure 750 psia, main seal leakage 3 x 0.00001 sccs at 35 psia valve inlet pressure, and a storage and operating life of 10 years. The valve was designed to be compatible with RP-1, propane, LH2, LO2, He, and N2.

  17. NASA Institute for Advanced Concepts

    NASA Technical Reports Server (NTRS)

    Cassanova, Robert A.

    1999-01-01

    The purpose of NASA Institute for Advanced Concepts (NIAC) is to provide an independent, open forum for the external analysis and definition of space and aeronautics advanced concepts to complement the advanced concepts activities conducted within the NASA Enterprises. The NIAC will issue Calls for Proposals during each year of operation and will select revolutionary advanced concepts for grant or contract awards through a peer review process. Final selection of awards will be with the concurrence of NASA's Chief Technologist. The operation of the NIAC is reviewed biannually by the NIAC Science, Exploration and Technology Council (NSETC) whose members are drawn from the senior levels of industry and universities. The process of defining the technical scope of the initial Call for Proposals was begun with the NIAC "Grand Challenges" workshop conducted on May 21-22, 1998 in Columbia, Maryland. These "Grand Challenges" resulting from this workshop became the essence of the technical scope for the first Phase I Call for Proposals which was released on June 19, 1998 with a due date of July 31, 1998. The first Phase I Call for Proposals attracted 119 proposals. After a thorough peer review, prioritization by NIAC and technical concurrence by NASA, sixteen subgrants were awarded. The second Phase I Call for Proposals was released on November 23, 1998 with a due date of January 31, 1999. Sixty-three (63) proposals were received in response to this Call. On December 2-3, 1998, the NSETC met to review the progress and future plans of the NIAC. The next NSETC meeting is scheduled for August 5-6, 1999. The first Phase II Call for Proposals was released to the current Phase I grantees on February 3,1999 with a due date of May 31, 1999. Plans for the second year of the contract include a continuation of the sequence of Phase I and Phase II Calls for Proposals and hosting the first NIAC Annual Meeting and USRA/NIAC Technical Symposium in NASA HQ.

  18. High efficiency solar photovoltaic power module concept

    NASA Technical Reports Server (NTRS)

    Bekey, I.

    1978-01-01

    The investigation of a preliminary concept for high efficiency solar power generation in space is presented. The concept was a synergistic combination of spectral splitting, tailored bandgap cells, high concentration ratios, and cool cell areas.

  19. Taiwanese Students' Alternative Conceptions of Animal Biodiversity

    ERIC Educational Resources Information Center

    Yen, Chiung-Fen; Yao, Tsung-Wei; Mintzes, Joel J.

    2007-01-01

    This study explored and documented Taiwanese students' alternative conceptions of animal classification. We examined the understanding of the "animal", "vertebrate" and "invertebrate", "fish", "amphibian", "reptile", "bird", and "mammal" concepts among elementary,…

  20. Asteroid Redirect Mission: Boulder Collection Concept

    NASA Video Gallery

    This animation illustrates one of two robotic mission concepts under consideration for NASA's Asteroid Redirect Mission. In this concept, the Asteroid Redirect Vehicle descends to the surface of a ...

  1. Self-Concept and Academic Progress.

    ERIC Educational Resources Information Center

    Hummel, Jeffrey W.; Cecil, Nancy Lee

    1984-01-01

    Focuses on the need for multimeasures of self-concept and self perceptions. Recommends the use of specific measures for academic self-concept, attitudes toward school, and attitudes toward specific subjects. (JAC)

  2. Supersonic wing design concepts employing nonlinear flows

    NASA Technical Reports Server (NTRS)

    Miller, D. S.

    1984-01-01

    Three nonlinear flow concepts for the design of supersonic wings are reviewed. The specific concepts are: leading-edge thrust, supercritical crossflow, and leading-edge vortex flow. The major results of the experimental-theoretical studies supporting the development of these concepts are presented and discussed. Also, supporting aerodynamic prediction methods are described and example applications are given. Recommendations for further development of each concept are made.

  3. A Survey of NATO Defense Concepts.

    DTIC Science & Technology

    1982-06-01

    receive broad endorsement-- current Theater Nuclear Weapons (TNW)[1] vul- nerabilities and the need to rectify them, NATO/WP imbalances caused by... current defense concepts or capabilities; what the main tenets of the author’s proposed concepts are; and how the concept is supposed to work. This...concepts for the defense of NA:’O. Each article was read for the author’s views on three topics: o Why a change is needed in NATO’s current defense

  4. Concepts for manned lunar habitats

    NASA Technical Reports Server (NTRS)

    Hypes, W. D.; Butterfield, A. J.; King, C. B.; Qualls, G. D.; Davis, W. T.; Gould, M. J.; Nealy, J. E.; Simonsen, L. C.

    1991-01-01

    The design philosophy that will guide the design of early lunar habitats will be based on a compromise between the desired capabilities of the base and the economics of its development and implantation. Preferred design will be simple, make use of existing technologies, require the least amount of lunar surface preparation, and minimize crew activity. Three concepts for an initial habitat supporting a crew of four for 28 to 30 days are proposed. Two of these are based on using Space Station Freedom structural elements modified for use in a lunar-gravity environment. A third concept is proposed that is based on an earlier technology based on expandable modules. The expandable modules offer significant advantages in launch mass and packaged volume reductions. It appears feasible to design a transport spacecraft lander that, once landed, can serve as a habitat and a stand-off for supporting a regolith environmental shield. A permanent lunar base habitat supporting a crew of twelve for an indefinite period can be evolved by using multiple initial habitats. There appears to be no compelling need for an entirely different structure of larger volume and increased complexity of implantation.

  5. Semantic search via concept annealing

    NASA Astrophysics Data System (ADS)

    Dunkelberger, Kirk A.

    2007-04-01

    Annealing, in metallurgy and materials science, is a heat treatment wherein the microstructure of a material is altered, causing changes in its properties such as strength and hardness. We define concept annealing as a lexical, syntactic, and semantic expansion capability (the removal of defects and the internal stresses that cause term- and phrase-based search failure) coupled with a directed contraction capability (semantically-related terms, queries, and concepts nucleate and grow to replace those originally deformed by internal stresses). These two capabilities are tied together in a control loop mediated by the information retrieval precision and recall metrics coupled with intuition provided by the operator. The specific representations developed have been targeted at facilitating highly efficient and effective semantic indexing and searching. This new generation of Find capability enables additional processing (i.e. all-source tracking, relationship extraction, and total system resource management) at rates, precisions, and accuracies previously considered infeasible. In a recent experiment, an order magnitude reduction in time to actionable intelligence and nearly three orderss magnitude reduction in false alarm rate was achieved.

  6. Grima: A Distinct Emotion Concept?

    PubMed

    Schweiger Gallo, Inge; Fernández-Dols, José-Miguel; Gollwitzer, Peter M; Keil, Andreas

    2017-01-01

    People experience an unpleasant sensation when hearing a scratch on a board or plate. The present research focuses on this aversive experience known in Spanish as 'grima' with no equivalent term in English and German. We hypothesized that this aversive experience constitutes a distinctive, separate emotional concept. In Study 1, we found that the affective meaning of 'grima' was closer to disgust than to other emotion concepts. Thus, in Study 2 we explored the features of grima and compared them with disgust. As grima was reported to be predominantly elicited by certain auditory stimuli and associated with a distinctive physiological pattern, Study 3 used direct measures of physiological arousal to test the assumption of a distinctive pattern of physiological responses elicited by auditory stimuli of grima and disgust, and found different effects on heart rate but not on skin conductance. In Study 4, we hypothesized that only participants with an implementation intention geared toward down-regulating grima would be able to successfully weaken the grima- but not disgust- experience. Importantly, this effect was specific as it held true for the grima-eliciting sounds only, but did not affect disgust-related sounds. Finally, Study 5 found that English and German speakers lack a single accessible linguistic label for the pattern of aversive reactions termed by Spanish speaking individuals as 'grima', whereas the elicitors of other emotions were accessible and accurately identified by German, English, as well as Spanish speakers.

  7. SATS HVO Concept Validation Experiment

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria; Williams, Daniel; Murdoch, Jennifer; Adams, Catherine

    2005-01-01

    A human-in-the-loop simulation experiment was conducted at the NASA Langley Research Center s (LaRC) Air Traffic Operations Lab (ATOL) in an effort to comprehensively validate tools and procedures intended to enable the Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) concept of operations. The SATS HVO procedures were developed to increase the rate of operations at non-towered, non-radar airports in near all-weather conditions. A key element of the design is the establishment of a volume of airspace around designated airports where pilots accept responsibility for self-separation. Flights operating at these airports, are given approach sequencing information computed by a ground based automated system. The SATS HVO validation experiment was conducted in the ATOL during the spring of 2004 in order to determine if a pilot can safely and proficiently fly an airplane while performing SATS HVO procedures. Comparative measures of flight path error, perceived workload and situation awareness were obtained for two types of scenarios. Baseline scenarios were representative of today s system utilizing procedure separation, where air traffic control grants one approach or departure clearance at a time. SATS HVO scenarios represented approaches and departure procedures as described in the SATS HVO concept of operations. Results from the experiment indicate that low time pilots were able to fly SATS HVO procedures and maintain self-separation as safely and proficiently as flying today's procedures.

  8. Grima: A Distinct Emotion Concept?

    PubMed Central

    Schweiger Gallo, Inge; Fernández-Dols, José-Miguel; Gollwitzer, Peter M.; Keil, Andreas

    2017-01-01

    People experience an unpleasant sensation when hearing a scratch on a board or plate. The present research focuses on this aversive experience known in Spanish as ‘grima’ with no equivalent term in English and German. We hypothesized that this aversive experience constitutes a distinctive, separate emotional concept. In Study 1, we found that the affective meaning of ‘grima’ was closer to disgust than to other emotion concepts. Thus, in Study 2 we explored the features of grima and compared them with disgust. As grima was reported to be predominantly elicited by certain auditory stimuli and associated with a distinctive physiological pattern, Study 3 used direct measures of physiological arousal to test the assumption of a distinctive pattern of physiological responses elicited by auditory stimuli of grima and disgust, and found different effects on heart rate but not on skin conductance. In Study 4, we hypothesized that only participants with an implementation intention geared toward down-regulating grima would be able to successfully weaken the grima- but not disgust- experience. Importantly, this effect was specific as it held true for the grima-eliciting sounds only, but did not affect disgust-related sounds. Finally, Study 5 found that English and German speakers lack a single accessible linguistic label for the pattern of aversive reactions termed by Spanish speaking individuals as ‘grima’, whereas the elicitors of other emotions were accessible and accurately identified by German, English, as well as Spanish speakers. PMID:28217102

  9. [The concepts of health access].

    PubMed

    Sanchez, Raquel Maia; Ciconelli, Rozana Mesquita

    2012-03-01

    This article describes four dimensions of health access-availability, acceptability, ability to pay and information-correlating these dimensions to indicators and discussing the complexity of the concept of access. For a study of these four dimensions, searches were conducted using the PubMed/MEDLINE, LILACS, SciELO, and World Health Organization Library & Information Networks for Knowledge (WHOLIS) databases. Large-circulation media vehicles, such as The Economist, The Washington Post, and the BBC network were also searched. The concept of health access has become more complex with time. The first analyses, carried out in the 1970s, suggested a strong emphasis on geographical (availability) and financial (ability to pay) aspects. More recently, the literature has focused on less tangible aspects, such as cultural, educational, and socioeconomic issues, incorporating the element of acceptability into the notion of health access. The literature also shows that information provides the starting point for access to health, in association with health empowerment and literacy for health care decision-making. The study concludes that improvements in access to health and the guarantee of equity will not be achieved by initiatives focusing on health care systems alone, but rather will depend on intersectoral actions and social and economic policies aimed at eliminating income and education differences.

  10. [Group cohesion: a concept analysis].

    PubMed

    Lin, Yen-Ru; Chen, Yu-Jung; Tzeng, Wen-Chii; Chou, Kuei-Ru

    2007-10-01

    Group cohesion is considered an essential condition for achieving a successful treatment team. High cohesion groups more readily reach their goals, with group members also feeling more secure about their functions and contributions. In clinical practice, nurses use group teaching and group therapy to help patient and family members gain knowledge and skills related to illness treatment and recuperation. Effective group leadership helps minimize non-productive time and manpower and enhance interpersonal interaction. A further advantage of group cohesion is that the more effective administration of nursing programs that results can raise the profession level of staffs and reduce turnover. Walker and Avant (1995) employ concept analysis to use defining attributes in order to apply the same definition and communication to the same profession. The purpose of this paper was to apply this methodology to an analysis of group cohesion. Steps used include a review of the literature on conceptual definitions of group cohesion, a determination of defining attributes, model construction, identification of borderline, contrary, and related cases, and identification of antecedents and consequences and empirical tools. It is hoped that this analysis can help nursing staff to gain a better understanding of the concept of group cohesion and to apply such to clinical practice and nursing administration.

  11. Grasp admittance center. A concept

    NASA Astrophysics Data System (ADS)

    Shimoga, K. B.; Goldenberg, A. A.

    1991-05-01

    The ultimate goal of the research on articulated hands in general is to use them to do tasks in a way similar to that of humans. A systematic analysis reveals that the day-to-day tasks of humans include some common task primitives such as twist, turn, insert, pullout, push, pull, lift, and place. During each of these operations, the grasp dynamic behavior plays an important role and more so in tasks involving manipulation of delicate objects. Introduced in this paper is the concept of the grasp admittance center, a notion that aims to make an articulated grasp exhibit a directionally decoupled dynamic behavior. An admittance center is conceptualized as the superposition of compliance, accommodation, and mobility centers in a desired coordinate frame. A grasp with an admittance center will have three useful features: stability, decoupled force motion relation, and decoupled time-response. These features are also useful to other closed kinematic chain robotic devices such as the cooperating multiarms and multilegged mobile robots engaged in non-quasistatic (dynamic) manipulation tasks. As a preparation to demonstrate the concept experimentally, a method of synthesizing articulated grasps so as to achieve an admittance center has been developed as well as a method of choosing appropriate location and related parameters for the center. The sensitivity of the center to its parameter imprecision has also been analyzed.

  12. Advanced concepts flight simulation facility.

    PubMed

    Chappell, S L; Sexton, G A

    1986-12-01

    The cockpit environment is changing rapidly. New technology allows airborne computerised information, flight automation and data transfer with the ground. By 1995, not only will the pilot's task have changed, but also the tools for doing that task. To provide knowledge and direction for these changes, the National Aeronautics and Space Administration (NASA) and the Lockheed-Georgia Company have completed three identical Advanced Concepts Flight Simulation Facilities. Many advanced features have been incorporated into the simulators - e g, cathode ray tube (CRT) displays of flight and systems information operated via touch-screen or voice, print-outs of clearances, cockpit traffic displays, current databases containing navigational charts, weather and flight plan information, and fuel-efficient autopilot control from take-off to touchdown. More importantly, this cockpit is a versatile test bed for studying displays, controls, procedures and crew management in a full-mission context. The facility also has an air traffic control simulation, with radio and data communications, and an outside visual scene with variable weather conditions. These provide a veridical flight environment to evaluate accurately advanced concepts in flight stations.

  13. Modern control concepts in hydrology

    NASA Technical Reports Server (NTRS)

    Duong, N.; Johnson, G. R.; Winn, C. B.

    1974-01-01

    Two approaches to an identification problem in hydrology are presented based upon concepts from modern control and estimation theory. The first approach treats the identification of unknown parameters in a hydrologic system subject to noisy inputs as an adaptive linear stochastic control problem; the second approach alters the model equation to account for the random part in the inputs, and then uses a nonlinear estimation scheme to estimate the unknown parameters. Both approaches use state-space concepts. The identification schemes are sequential and adaptive and can handle either time invariant or time dependent parameters. They are used to identify parameters in the Prasad model of rainfall-runoff. The results obtained are encouraging and conform with results from two previous studies; the first using numerical integration of the model equation along with a trial-and-error procedure, and the second, by using a quasi-linearization technique. The proposed approaches offer a systematic way of analyzing the rainfall-runoff process when the input data are imbedded in noise.

  14. Concepts for a short wavelength rf gun

    NASA Astrophysics Data System (ADS)

    Kuzikov, S. V.; Shchelkunov, S.; Vikharev, A. A.

    2017-03-01

    Three concepts of an rf gun to be operated at 0.1-10 mm wavelengths are considered. In all the concepts, the rf system exploits an accelerating traveling wave. In comparison with a classical decimeter standing-wave rf gun, we analyze the advantages of new concepts, available rf sources, and achievable beam parameters.

  15. Reflection: Its Concepts and Applications in Geometry

    ERIC Educational Resources Information Center

    Man, Yiu Kwong

    2004-01-01

    This paper discusses the basic concepts of reflection and its related concepts in optics. It aims at providing examples on how to apply the principle of reflection in geometry. Explorations of the concepts involved via dynamic geometry software are also included.

  16. Fundamental Concepts Bridging Education and the Brain

    ERIC Educational Resources Information Center

    Masson, Steve; Foisy, Lorie-Marlène Brault

    2014-01-01

    Although a number of papers have already discussed the relevance of brain research for education, the fundamental concepts and discoveries connecting education and the brain have not been systematically reviewed yet. In this paper, four of these concepts are presented and evidence concerning each one is reviewed. First, the concept of…

  17. Twelve Major Concept Categories and Their Rationale.

    ERIC Educational Resources Information Center

    Howlett, George

    Twelve concepts utilized by Project I-C-E (Instruction-Curriculum-Environment) for integrating science, social studies, and language arts with environmental studies are elaborated in this booklet. The rationale for each concept is put forth together with a more detailed explanation of the concept. Topics considered include: energy, ecosystems,…

  18. Concept Mapping: Developing Guides to Literature.

    ERIC Educational Resources Information Center

    Leahy, Robert

    1989-01-01

    Concept maps, diagrams that show the relationships among concepts in a piece of writing, can help students travel through literature to destinations that they can identify and defend. The use of concept maps for Ernest Hemingway's "The Old Man and The Sea" and Albert Camus'"The Stranger" is described. (MLW)

  19. Reconceptualization of African American Self-Concept.

    ERIC Educational Resources Information Center

    Braithwaite, Harold, Jr.; And Others

    1994-01-01

    Focuses on how African American students define self-concept, and whether there is a specific black self-concept. Questionnaires completed by 60 undergraduates at a historically black college provide insight into student self-esteem and support the existence of a specific black self-concept. (SLD)

  20. Unified Technical Concepts. Module 1: Force.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on force is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system. This…

  1. Unified Technical Concepts. Module 2: Work.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on work is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system. In this…

  2. Essential Map Concepts for Young Children.

    ERIC Educational Resources Information Center

    Hatcher, Barbara

    This paper discusses four key concepts to help preschool and primary grade children develop the ability to read and understand maps. Examples of student activities to develop each of the concepts are provided. The essential concepts are representation, symbolization, perspective, and scale. Representation is vital. Children must perceive that a…

  3. Concept Mapping: An "Instagram" of Students' Thinking

    ERIC Educational Resources Information Center

    Campbell, Laurie O.

    2016-01-01

    Minimal research has been accumulated in the field of social studies education for Novakian concept mapping, yet there are many benefits from adding this learning tool to a teacher's instructional toolbox. The article defines Novakian concept mapping and invites readers to adopt digital Novakian concept mapping into the social studies classroom as…

  4. Learning with Retrieval-Based Concept Mapping

    ERIC Educational Resources Information Center

    Blunt, Janell R.; Karpicke, Jeffrey D.

    2014-01-01

    Students typically create concept maps while they view the material they are trying to learn. In these circumstances, concept mapping serves as an elaborative study activity--students are not required to retrieve the material they are learning. In 2 experiments, we examined the effectiveness of concept mapping when it is used as a retrieval…

  5. Unified Technical Concepts. Module 10: Transducers.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on transducers is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system.…

  6. Self-Concept Change in Camp Staff.

    ERIC Educational Resources Information Center

    Henderson, Karla A.; Bialeschki, M. Deborah

    The 1981 study ascertained whether the self-concept of 66 camp staff from 2 Wisconsin camps changed more than a control group of 18 college students attending summer school; if differences in self-concept were based on a particular characteristic (age, gender, staff position, years at camp); and in what ways, if any, self-concept of camp staff…

  7. Unified Technical Concepts. Module 9: Energy Convertors.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on energy convertors is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy…

  8. Investigating Elementary Teachers' Conceptions of Animal Classification

    ERIC Educational Resources Information Center

    Burgoon, Jacob N.; Duran, Emilio

    2012-01-01

    Numerous studies have been conducted regarding alternative conceptions about animal diversity and classification, many of which have used a cross-age approach to investigate how students' conceptions change over time. None of these studies, however, have investigated teachers' conceptions of animal classification. This study was intended to…

  9. Unified Technical Concepts. Module 12: Time Constants.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on time constants is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy…

  10. Nascent Function Concepts in Nova Scientia

    ERIC Educational Resources Information Center

    Groetsch, C. W.

    2004-01-01

    The origin of the function concept is usually traced to Galileo's work on motion. We argue that specific proto-function concepts appeared in the work of Tartaglia a century before the publication of Galileo's Two New Sciences. The study of Tartaglia's ideas can be used in the classroom as a historical introduction to various function concepts,…

  11. Unified Technical Concepts. Module 6: Power.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on power is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system. In this…

  12. Unified Technical Concepts. Module 13: Radiation.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on radiation is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system.…

  13. Relativity Concept Inventory: Development, Analysis, and Results

    ERIC Educational Resources Information Center

    Aslanides, J. S.; Savage, C. M.

    2013-01-01

    We report on a concept inventory for special relativity: the development process, data analysis methods, and results from an introductory relativity class. The Relativity Concept Inventory tests understanding of relativistic concepts. An unusual feature is confidence testing for each question. This can provide additional information; for example,…

  14. Unified Technical Concepts. Module 4: Momentum.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on momentum is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system. This…

  15. Self-Concept Enhancement of Preschool Children.

    ERIC Educational Resources Information Center

    Landry, Richard G.; Pardew, E. Michelle

    This study investigated whether a self-concept enhancement program would effect significant change in the self-concepts of 4-year-old middle class preschoolers as compared with classmates not in the program. All participating children (N=52) were pre- and posttested using the Thomas Self-Concept Values Test and the Developmental Profile. The…

  16. Unified Technical Concepts. Module 8: Force Transformers.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on force transformers is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy…

  17. Students' Formalising Process of the Limit Concept

    ERIC Educational Resources Information Center

    Kabael, Tangul

    2014-01-01

    The concept of limit is the foundation for many concepts such as the derivative and the integral in advanced mathematics. The limit concept has been a research topic in mathematics education for years and in the literature it is a broadly accepted fact that the limit is a difficult notion for most students. The study presented in this article is a…

  18. Unified Technical Concepts. Module 5: Resistance.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on resistance is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system.…

  19. Unified Technical Concepts. Module 3: Rate.

    ERIC Educational Resources Information Center

    Technical Education Research Center, Waco, TX.

    This concept module on rate is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each energy system. This…

  20. Threshold Concepts in Finance: Student Perspectives

    ERIC Educational Resources Information Center

    Hoadley, Susan; Kyng, Tim; Tickle, Leonie; Wood, Leigh N.

    2015-01-01

    Finance threshold concepts are the essential conceptual knowledge that underpin well-developed financial capabilities and are central to the mastery of finance. In this paper we investigate threshold concepts in finance from the point of view of students, by establishing the extent to which students are aware of threshold concepts identified by…

  1. The Europa Clipper Mission Concept

    NASA Astrophysics Data System (ADS)

    Pappalardo, Robert; Goldstein, Barry; Magner, Thomas; Prockter, Louise; Senske, David; Paczkowski, Brian; Cooke, Brian; Vance, Steve; Wes Patterson, G.; Craft, Kate

    2014-05-01

    A NASA-appointed Science Definition Team (SDT), working closely with a technical team from the Jet Propulsion Laboratory (JPL) and the Applied Physics Laboratory (APL), recently considered options for a future strategic mission to Europa, with the stated science goal: Explore Europa to investigate its habitability. The group considered several mission options, which were fully technically developed, then costed and reviewed by technical review boards and planetary science community groups. There was strong convergence on a favored architecture consisting of a spacecraft in Jupiter orbit making many close flybys of Europa, concentrating on remote sensing to explore the moon. Innovative mission design would use gravitational perturbations of the spacecraft trajectory to permit flybys at a wide variety of latitudes and longitudes, enabling globally distributed regional coverage of the moon's surface, with nominally 45 close flybys at altitudes from 25 to 100 km. We will present the science and reconnaissance goals and objectives, a mission design overview, and the notional spacecraft for this concept, which has become known as the Europa Clipper. The Europa Clipper concept provides a cost-efficient means to explore Europa and investigate its habitability, through understanding the satellite's ice and ocean, composition, and geology. The set of investigations derived from the Europa Clipper science objectives traces to a notional payload for science, consisting of: Ice Penetrating Radar (for sounding of ice-water interfaces within and beneath the ice shell), Topographical Imager (for stereo imaging of the surface), ShortWave Infrared Spectrometer (for surface composition), Neutral Mass Spectrometer (for atmospheric composition), Magnetometer and Langmuir Probes (for inferring the satellite's induction field to characterize an ocean), and Gravity Science (to confirm an ocean).The mission would also include the capability to perform reconnaissance for a future lander

  2. [Concept dimension for nursing and Deleuze].

    PubMed

    de Freitas, Maria Célia; Mendes, Maria Manuela Rino

    2004-01-01

    The study aimed at identifying and analyzing the meaning of concept according to Deleuze, in Philosophy, and Rodgers, in Nursing. Based on an extract of reality, Deleuze creates the concept and calls it "plan of immanence". For Rodgers, in nursing, the concept emerges at the actual moment one wishes to construct the conceptual bases for Nursing. The authors demonstrate that, although Deleuze and Rodgers come from different areas, the meaning they attribute to concept shares the happening of things and beings, which reflect the experienced reality. For Rodgers, the concept is characterized by its essential elements while, for Deleuze, by what he called components, that is, by essence.

  3. Ancient "Observatories" - A Relevant Concept?

    NASA Astrophysics Data System (ADS)

    Belmonte, Juan Antonio

    It is quite common, when reading popular books on astronomy, to see a place referred to as "the oldest observatory in the world". In addition, numerous books on archaeoastronomy, of various levels of quality, frequently refer to the existence of "prehistoric" or "ancient" observatories when describing or citing monuments that were certainly not built with the primary purpose of observing the skies. Internet sources are also guilty of this practice. In this chapter, the different meanings of the word observatory will be analyzed, looking at how their significances can be easily confused or even interchanged. The proclaimed "ancient observatories" are a typical result of this situation. Finally, the relevance of the concept of the ancient observatory will be evaluated.

  4. Cultural Humility: A Concept Analysis.

    PubMed

    Foronda, Cynthia; Baptiste, Diana-Lyn; Reinholdt, Maren M; Ousman, Kevin

    2016-05-01

    Diversity is being increasingly recognized as an area of emphasis in health care. The term cultural humility is used frequently but society's understanding of the term is unclear. The aim of this article was to provide a concept analysis and a current definition for the term cultural humility. Cultural humility was used in a variety of contexts from individuals having ethnic and racial differences, to differences in sexual preference, social status, interprofessional roles, to health care provider/patient relationships. The attributes were openness, self-awareness, egoless, supportive interactions, and self-reflection and critique. The antecedents were diversity and power imbalance. The consequences were mutual empowerment, partnerships, respect, optimal care, and lifelong learning. Cultural humility was described as a lifelong process. With a firm understanding of the term, individuals and communities will be better equipped to understand and accomplish an inclusive environment with mutual benefit and optimal care.

  5. Miniaturized Cassegrainian concentrator concept demonstration

    NASA Astrophysics Data System (ADS)

    Patterson, R. E.; Rauschenbach, H. S.

    High concentration ratio photovoltaic systems for space applications have generally been considered impractical because of perceived difficulties in controlling solar cell temperatures to reasonably low values. A miniaturized concentrator system is now under development which surmounts this objection by providing acceptable solar cell temperatures using purely passive cell cooling methods. An array of identical miniaturized, rigid Cassegrainian optical systems having a low f-number with resulting short dimensions along their optical axes are rigidly mounted into a frame to form a relatively thin concentrator solar array panel. A number of such panels, approximately 1.5 centimeters thick, are wired as an array and are folded against one another for launch in a stowed configuration. Deployment on orbit is similar to the deployment of conventional planar honeycomb panel arrays or flexible blanket arrays. The miniaturized concept was conceived and studied in the 1978-80 time frame. Progress in the feasibility demonstration to date is reported.

  6. Anomalous intense driver (AID) concept

    SciTech Connect

    Thode, L.E.

    1980-03-01

    An optimized electron bunching mechanism is utilized to efficiently couple the energy of a 5 to 100 MeV, 1 to 30 TW electron beam into a 3 to 50 cm/sup 3/ plasma of electron density 10/sup 17/ to 10/sup 20/ cm-/sup 3/. An efficient coupling of beam energy and momentum to the plasma is possible due to the relativistic nature of the beam dynamics combined with the short wavelength of the bunching mechanism in a high-density plasma. The rapidly produced multi-kilovolt plasma can be used directly to develop a pulsed neutron and x-ray source. Alternatively, the plasma can be used to drive a hierarchy of inertial confinement or x-ray devices. Utilizing this novel concept, controlled thermonuclear fusion may be achievable within present or near term relativistic electron beam technology.

  7. Overdiagnosis: epidemiologic concepts and estimation.

    PubMed

    Bae, Jong-Myon

    2015-01-01

    Overdiagnosis of thyroid cancer was propounded regarding the rapidly increasing incidence in South Korea. Overdiagnosis is defined as 'the detection of cancers that would never have been found were it not for the screening test', and may be an extreme form of lead bias due to indolent cancers, as is inevitable when conducting a cancer screening programme. Because it is solely an epidemiological concept, it can be estimated indirectly by phenomena such as a lack of compensatory drop in post-screening periods, or discrepancies between incidence and mortality. The erstwhile trials for quantifying the overdiagnosis in screening mammography were reviewed in order to secure the data needed to establish its prevalence in South Korea.

  8. Mars Telecommunications Orbiter, Artist's Concept

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This illustration depicts a concept for NASA's Mars Telecommunications Orbiter in flight around Mars. The orbiter is in development to be the first spacecraft with a primary function of providing communication links while orbiting a foreign planet. The project's plans call for launch in September 2009, arrival at Mars in August 2010 and a mission of six to 10 years while in orbit. Mars Telecommunication Orbiter would serve as the Mars hub for an interplanetery Internet, greatly increasing the information payoff from other future Mars missions. The mission is designed to orbit Mars more than 10 times farther from the planet than orbiters dedicated primarily to science. The high-orbit design minimizes the time that Mars itself blocks the orbiter from communicating with Earth and maximizes the time that the orbiter is above the horizon -- thus capable of communications relay -- for rovers and stationary landers on Mars' surface.

  9. NSLS-II INJECTION CONCEPT.

    SciTech Connect

    SHAFTAN, T.; PINAYEV, I.; ROSE, J.; WANG, X.J.; ET AL.

    2005-05-16

    Currently the facility upgrade project is in progress at the NSLS (at Brookhaven National Laboratory). The goal of the NSLS-II is a 3 GeV ultra-low-emittance storage ring that will increase radiation brightness by three orders of magnitude over that of the present NSLS X-ray ring. The low emittance of the high brightness ring's lattice results in a short lifetime, so that a top-off injection mode becomes an operational necessity. Therefore, the NSLS-II injection system must provide, and efficiently inject, an electron beam at a high repetition rate. In this paper, we present our concept of the NSLS-II injection system and discuss the conditions for, and constraints on, its design.

  10. Fundamental concepts of quantum chaos

    NASA Astrophysics Data System (ADS)

    Robnik, M.

    2016-09-01

    We review the fundamental concepts of quantum chaos in Hamiltonian systems. The quantum evolution of bound systems does not possess the sensitive dependence on initial conditions, and thus no chaotic behaviour occurs, whereas the study of the stationary solutions of the Schrödinger equation in the quantum phase space (Wigner functions) reveals precise analogy of the structure of the classical phase portrait. We analyze the regular eigenstates associated with invariant tori in the classical phase space, and the chaotic eigenstates associated with the classically chaotic regions, and the corresponding energy spectra. The effects of quantum localization of the chaotic eigenstates are treated phenomenologically, resulting in Brody-like level statistics, which can be found also at very high-lying levels, while the coupling between the regular and the irregular eigenstates due to tunneling, and of the corresponding levels, manifests itself only in low-lying levels.

  11. Simulator Fidelity: A Concept Paper

    DTIC Science & Technology

    1980-11-01

    cnLUMB8iS 1.AUORATORIES TACTICAL TECHNICAL OJýC I USA ARHCTIC TESI CEN ATTN: AMStL-PL-TS 1 UISA cOLD RFGIONS TEST CEN ATTr4: STECR-up I USA t.UNCkP7S ANALYSiS...AbLY ATTNI LSCA-wop 1 USA CONCEPTS ANALYSIS AGCY ATTN$ CSCA-JF I Hu wewAIH nIV Q * 𔃾LUNUPSY4.MIAIRV I UJSAC’ACtA ATTN: ATIL-..AC-1C I USACiaCUA ATINI...ATTN: AILK-li) I USA aRMOM CENT~ q ijINk.IUhkA1l ;)1 (UMSAT J~VELUI0MtNTS, 1 NAVA$ POSTGRAOUAT-- SCH A7TN: oLULEy ’kNUX LIdRARY (COOF 14;0.) 1 USA

  12. Unifying physical concepts of reality

    SciTech Connect

    Gilbert, T.L.

    1983-08-01

    Physics may be characterized as the science of matter and energy. It anchors the two ends of the frontiers of science: the frontier of the very small and the frontier of the very large. All of the phenomena that we observe and study at the frontiers of science - all external experiences - are manifestations of matter and energy. One may, therefore, use physics to exemplify both the diversity and unity of science. This theme will be developed in two separate examples: first by sketching, very briefly, the historical origins of frontiers of the very small and very large and the converging unity of these two frontiers; and then by describing certain unifying concepts that play a central role in physics and provide a framework for relating developments in different sciences.

  13. Modular Stellarator Fusion Reactor concept

    SciTech Connect

    Miller, R.L.; Krakowski, R.A.

    1981-08-01

    A preliminary conceptual study is made of the Modular Stellarator Reactor (MSR). A steady-state ignited, DT-fueled, magnetic fusion reactor is proposed for use as a central electric-power station. The MSR concept combines the physics of the classic stellarator confinement topology with an innovative, modular-coil design. Parametric tradeoff calculations are described, leading to the selection of an interim design point for a 4-GWt plant based on Alcator transport scaling and an average beta value of 0.04 in an l = 2 system with a plasma aspect ratio of 11. The physics basis of the design point is described together with supporting magnetics, coil-force, and stress computations. The approach and results presented herein will be modified in the course of ongoing work to form a firmer basis for a detailed conceptual design of the MSR.

  14. Manned Mars Mission program concepts

    NASA Technical Reports Server (NTRS)

    Hamilton, E. C.; Johnson, P.; Pearson, J.; Tucker, W.

    1988-01-01

    This paper describes the SRS Manned Mars Mission and Program Analysis study designed to support a manned expedition to Mars contemplated by NASA for the purposes of initiating human exploration and eventual habitation of this planet. The capabilities of the interactive software package being presently developed by the SRS for the mission/program analysis are described, and it is shown that the interactive package can be used to investigate the impact of various mission concepts on the sensitivity of mass required in LEO, schedules, relative costs, and risk. The results, to date, indicate the need for an earth-to-orbit transportation system much larger than the present STS, reliable long-life support systems, and either advanced propulsion or aerobraking technology.

  15. Plutonium Immobilization Can Loading Concepts

    SciTech Connect

    Kriikku, E.; Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.; Rogers, L.; Fiscus, J.; Dyches, G.

    1998-05-01

    The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses five can loading conceptual designs and the lists the advantages and disadvantages for each concept. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas. The can loading welder and cutter are very similar to the existing Savannah River Site (SRS) FB-Line bagless transfer welder and cutter and thus they are a low priority development item.

  16. Culture and concepts of power.

    PubMed

    Torelli, Carlos J; Shavitt, Sharon

    2010-10-01

    Five studies indicate that conceptualizations of power are important elements of culture and serve culturally relevant goals. These studies provide converging evidence that cultures nurture different views of what is desirable and meaningful to do with power. Vertical individualism is associated with a conceptualization of power in personalized terms (i.e., power is for advancing one's personal status and prestige), whereas horizontal collectivism is associated with a conceptualization of power in socialized terms (i.e., power is for benefiting and helping others). Cultural variables are shown to predict beliefs about appropriate uses of power, episodic memories about power, attitudes in the service of power goals, and the contexts and ways in which power is used and defended. Evidence for the cultural patterning of power concepts is observed at both the individual level and the cultural-group level of analysis.

  17. Radioisotope Power System Pool Concept

    NASA Technical Reports Server (NTRS)

    Rusick, Jeffrey J.; Bolotin, Gary S.

    2015-01-01

    Advanced Radioisotope Power Systems (RPS) for NASA deep space science missions have historically used static thermoelectric-based designs because they are highly reliable, and their radioisotope heat sources can be passively cooled throughout the mission life cycle. Recently, a significant effort to develop a dynamic RPS, the Advanced Stirling Radioisotope Generator (ASRG), was conducted by NASA and the Department of Energy, because Stirling based designs offer energy conversion efficiencies four times higher than heritage thermoelectric designs; and the efficiency would proportionately reduce the amount of radioisotope fuel needed for the same power output. However, the long term reliability of a Stirling based design is a concern compared to thermoelectric designs, because for certain Stirling system architectures the radioisotope heat sources must be actively cooled via the dynamic operation of Stirling converters throughout the mission life cycle. To address this reliability concern, a new dynamic Stirling cycle RPS architecture is proposed called the RPS Pool Concept.

  18. X-33 artist concept - 1999

    NASA Technical Reports Server (NTRS)

    1999-01-01

    An artist's conception of the half scale X-33 demonstrator flying over the southwestern desert. The vehicle was a wedge-shaped lifting body, with two vertical fins and a pair of stub wings. On the fins are the Lockheed-Martin Skunk Works logo, which was the prime contractor. At the rear is the aerospike engine, an experimental design that lacked the nozzles of conventional rockets. The X-33 tested several other new technologies, including composite structures and a metallic thermal protection system. It was hoped that these advances would lead eventually to an operational single-stage-to-orbit reusable launch vehicle called the VentureStar. However, due to technical problems with the composite liquid hydrogen tank, the X-33 program was cancelled in February 2001.

  19. Reinventing the state spaceport concept

    NASA Astrophysics Data System (ADS)

    Gormel, Edmond

    2002-01-01

    Spaceport Florida Authority, or ``the Authority,'' is meeting the challenge of reinventing the state spaceport concept. The Authority, an economic and academic development agency and a transportation authority that maximizes the strong NASA and military space presence in the state of Florida, serves as a facilitator among industry, education and government sectors that reside on or use Florida's spaceport. This paper discusses the state of Florida's progression in the business of space. From Florida's vision to be a leader in the commercialization of space to it's current role of partnering to grow over six hundred and fifty ($650) million dollars in new space programs. Executive Director Ed Gormel's strategy for reinventing a state spaceport is outlined in the paper. These guidelines, which he believes reflect the needs of the twenty-first century customer, include customer support, financing, property access and a means to provide dependable infrastructure. .

  20. Concept analysis: some limitations and possible solutions.

    PubMed

    Botes, A

    2002-08-01

    Concepts are the basic building blocks of scientific knowledge or theoretical frameworks for any discipline. The strength of the theories that guide a discipline is dependent on the quality of the concept analysis. Thus, the utilisation of poorly understood concepts in research and theory development will result in questionable reliability and validity. Concept analysis is associated with the research design of philosophical inquiry. The purpose of philosophical inquiry is to perform research using intellectual analysis to clarify meaning. Traditionally, no empirical (qualitative or quantitative) investigations were used to clarify the meaning of concepts. The lack of empirical investigation to clarify concepts, results in certain limitations in the methodology of concept analysis. It seems that methodological innovations for enhancing concept analysis is urgently required. The purpose of this article is to describe the utilisation of qualitative and quantitative strategies with literature review in concept analysis as a possible solution to limitations. This article will firstly, describe the limitations in the traditional Wilsonian methods of concept analysis and will secondly demonstrate how the introduction of qualitative and quantitative methods with literature review can overcome some of the limitations. An example a research study on quality of life (Ferrans, 1997:110) will be used to demonstrate how qualitative and quantitative empirical methods with literature review can enhance the quality of concept analysis.

  1. Concepts for Biologically Active Peptides

    PubMed Central

    Kastin, Abba J.; Pan, Weihong

    2012-01-01

    Here we review a unique aspect of CNS research on biologically active peptides that started against a background of prevalent dogmas but ended by exerting considerable influence on the field. During the course of refuting some doctrines, we introduced several concepts that were unconventional and paradigm-shifting at the time. We showed that (1) hypothalamic peptides can act ‘up’ on the brain as well as ‘down’ on the pituitary, (2) peripheral peptides can affect the brain, (3) peptides can cross the blood-brain barrier, (4) the actions of peptides can persist longer than their half-lives in blood, (5) perinatal administration of peptides can exert actions persisting into adulthood, (6) a single peptide can have more than one action, (7) dose-response relationships of peptides need not be linear, (8) the brain produces antiopiate as well as opiate peptides, (9) there is a selective high affinity endogenous peptide ligand for the mu-opiate receptor, (10) a peptide’s name does not restrict its effects, and (11) astrocytes assume an active role in response to metabolic disturbance and hyperleptinemia. The evolving questions in our laboratories reflect the diligent effort of the neuropeptide community to identify the roles of peptides in the CNS. The next decade is expected to see greater progress in the following areas: (a) interactions of peptides with other molecules in the CNS; (b) peptide involvement in cell-cell interactions; and (c) peptides in neuropsychiatric, autoimmune, and neurodegenerative diseases. The development of peptidomics and gene silencing approaches will expedite the formation of many new concepts in a new era. PMID:20726835

  2. [Biological mutualism, concepts and models].

    PubMed

    Perru, Olivier

    2011-01-01

    Mutualism is a biological association for a mutual benefit between two different species. In this paper, firstly, we examine the history and signification of mutualism in relation to symbiosis. Then, we consider the link between concepts and models of mutualism. Models of mutualism depend on different concepts we use: If mutualism is situated at populations' level, it will be expressed by Lotka-Volterra models, concerning exclusively populations' size. If mutualism is considered as a resources' exchange or a biological market increasing the fitness of these organisms, it will be described at an individual level by a cost-benefit model. Our analysis will be limited to the history and epistemology of Lotka-Volterra models and we hypothesize that these models are adapted at first to translate dynamic evolutions of mutualism. They render stability or variations of size and assume that there are clear distinctions and a state of equilibrium between populations of different species. Italian mathematician Vito Volterra demonstrated that biological associations consist in a constant relation between some species. In 1931 and 1935, Volterra described the general form of antagonistic or mutualistic biological associations by the same differential equations. We recognize that these equations have been more used to model competition or prey-predator interactions, but a simple sign change allows describing mutualism. The epistemological problem is the following: Volterra's equations help us to conceptualize a global phenomenon. However, mutualistic interactions may have stronger effects away from equilibrium and these effects may be better understood at individual level. We conclude that, between 1985 and 2000, some researchers carried on working and converting Lotka-Volterra models but this description appeared as insufficient. So, other researchers adopted an economical viewpoint, considering mutualism as a biological market.

  3. Mars Surface Tunnel Element Concept

    NASA Technical Reports Server (NTRS)

    Rucker, Michelle A.

    2016-01-01

    How crews get into or out of their ascent vehicle has profound implications for Mars surface architecture. Extravehicular Activity (EVA) hatches and Airlocks have the benefit of relatively low mass and high Technology Readiness Level (TRL), but waste consumables with a volume depressurization for every ingress/egress. Perhaps the biggest drawback to EVA hatches or Airlocks is that they make it difficult to keep Martian dust from being tracked back into the ascent vehicle, in violation of planetary protection protocols. Suit ports offer the promise of dust mitigation by keeping dusty suits outside the cabin, but require significant cabin real estate, are relatively high mass, and current operational concepts still require an EVA hatch to get the suits outside for the first EVA, and back inside after the final EVA. This is primarily because current designs don't provide enough structural support to protect the suits from ascent/descent loads or potential thruster plume impingement. For architectures involving more than one surface element-such as an ascent vehicle and a rover or surface habitat-a retractable tunnel is an attractive option. By pushing spacesuit don/doff and EVA operations to an element that remains on the surface, ascended vehicle mass and dust can be minimized. What's more, retractable tunnels provide operational flexibility by allowing surface assets to be re-configured or built up over time. Retractable tunnel functional requirements and design concepts being developed as part of the National Aeronautics and Space Administration's (NASA) Evolvable Mars Campaign (EMC) work will add a new ingress/egress option to the surface architecture trade space.

  4. Space Debris Environent Remediation Concepts

    NASA Astrophysics Data System (ADS)

    Klinkrad, H.; Johnson, N. L.

    2009-03-01

    Long-term projections of the space debris environment indicate that even drastic measures, such as an immediate, complete halt of launch and release activities, will not result in a stable environment of man-made space objects. Collision events between already existing space hardware will within a few decades start to dominate the debris population, and result in a net increase of the space debris population, also at sizes which may cause further catastrophic collisions. A collisional cascading may ultimately lead to a run-away situation ("Kessler syndrome"), with no further possibility of human intervention.The International Academy of Astronautics (IAA) has been investigating the status and the stability of the space debris environment in several studies by first looking into space traffic management possibilities, and then investigating means of mitigating the creation of space debris. In an on-going activity, an IAA study group looks into methods of active space debris environment remediation. In contrast to the former mitigation study, the current activity concentrates on the active removal of large objects, such as defunct spacecraft, orbital stages, and mission-related objects, which serve as a latent mass reservoir that fuels initial castastrophic collisions and later collisional cascading. The paper will outline different mass removal concepts, e.g. based on directed energy, tethers (momentum exchange or electro-dynamic), aerodynamic drag augmentation, solar sails, auxiliary propulsion units, retarding surfaces, or on-orbit capture. Apart from physical principles of the proposed concepts, their applicability to different orbital regimes, and their effectiveness concerning mass removal efficiency will be discussed.

  5. On the failure of modern species concepts.

    PubMed

    Hey, Jody

    2006-08-01

    The modern age of species concepts began in 1942, when Ernst Mayr gave concept names to several different approaches to species identification. A long list of species concepts then followed, as well as a complex literature on their merits, motivations and uses. Some of these complexities arose as a consequence of the semantic shift that Mayr introduced, in which procedures for identifying species were elevated to concepts. Much of the debate in recent decades over concepts, and over pluralism versus monism, can be seen as an unnecessary consequence of treating species identification criteria as if they were more fundamental concepts. Recently, biologists have begun to recognize both the shortcomings of a lexicon of multiple species concepts and a common evolutionary idea that underlies them.

  6. The semantic richness of abstract concepts

    PubMed Central

    Recchia, Gabriel; Jones, Michael N.

    2012-01-01

    We contrasted the predictive power of three measures of semantic richness—number of features (NFs), contextual dispersion (CD), and a novel measure of number of semantic neighbors (NSN)—for a large set of concrete and abstract concepts on lexical decision and naming tasks. NSN (but not NF) facilitated processing for abstract concepts, while NF (but not NSN) facilitated processing for the most concrete concepts, consistent with claims that linguistic information is more relevant for abstract concepts in early processing. Additionally, converging evidence from two datasets suggests that when NSN and CD are controlled for, the features that most facilitate processing are those associated with a concept's physical characteristics and real-world contexts. These results suggest that rich linguistic contexts (many semantic neighbors) facilitate early activation of abstract concepts, whereas concrete concepts benefit more from rich physical contexts (many associated objects and locations). PMID:23205008

  7. Concept Analysis of Illness Engulfment in Schizophrenia.

    PubMed

    Vining, Danny; Robinson, Jennifer C

    2016-06-01

    Schizophrenia has a significant risk of damaging an individual's self-concept. Through the process of illness engulfment an individual's self-concept becomes reorganized entirely around the experience of having schizophrenia. The purpose of this manuscript is to clarify the structure and function of the concept of illness engulfment in schizophrenia using Walker and Avant's (2011) method of concept analysis. Data came from a review of scholarly literature, as well as contemporary and historical art, literature, music, and other media forms. The analysis discussed two defining attributes of experience of illness and impact on self-concept with a total of seven indicators. The article listed antecedents, consequences, and discussed the Modified Engulfment Scale as empirical referents. Fictional cases were developed to illustrate the concept. Finally, the concept of illness engulfment was discussed within the framework of the Roy Adaptation Model.

  8. University Students' Conceptions about the Concept of Gene: Interest of Historical Approach

    ERIC Educational Resources Information Center

    Boujemaa, Agorram; Pierre, Clement; Sabah, Selmaoui; Salaheddine, Khzami; Jamal, Chafik; Abdellatif, Chiadli

    2010-01-01

    Concepts of genetics are often difficult to teach, specifically the central concept of gene. Even the scientists disagree when defining this concept. This paper investigates university students' understanding about the gene and its functions. The results show the dominance of two conceptions of the gene: the Neoclassical model and the Mendelian…

  9. Conceptions of Learning versus Conceptions of Web-Based Learning: The Differences Revealed by College Students

    ERIC Educational Resources Information Center

    Tsai, Chin-Chung

    2009-01-01

    Past research has shown the variations of students' conceptions of learning, but little has been especially undertaken to address students' conceptions of web-based learning and to make comparisons between students' conceptions of learning in general and their conceptions of web-based learning in particular. By interviewing 83 Taiwanese college…

  10. Evolutionary space platform concept study. Volume 2, part B: Manned space platform concepts

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Logical, cost-effective steps in the evolution of manned space platforms are investigated and assessed. Tasks included the analysis of requirements for a manned space platform, identifying alternative concepts, performing system analysis and definition of the concepts, comparing the concepts and performing programmatic analysis for a reference concept.

  11. Formal concept analysis and linguistic hedges

    NASA Astrophysics Data System (ADS)

    Belohlavek, Radim; Vychodil, Vilem

    2012-07-01

    This paper presents an application of linguistic hedges to formal concept analysis of data with fuzzy attributes. Formal concept analysis aims at extraction of particular (bi-)clusters, called formal concepts, from data. The clusters link collections of objects (extents) and attributes (intents), and have a clear interpretation due to a simple verbal description of the concept-forming operators. We insert linguistic hedges such as 'very' or 'extremely' in the description of the operators. In this way, linguistic hedges become parameters for formal concept analysis that control the number of clusters extracted from data. Namely, as we show theoretically as well as experimentally, stronger hedges result in a smaller number of clusters. The new concept-forming operators form Galois-like connections. We study their properties and axiomatize them. Then, we show that a concept lattice with hedges, i.e. the set of all formal concepts of the new operators is indeed a complete lattice which is isomorphic to a particular ordinary concept lattice. We describe the isomorphism and its inverse. These mappings serve as translation procedures. As a consequence, we obtain a theorem characterizing the structure of concept lattices with hedges which generalizes the well-known main theorem of ordinary concept lattices. The isomorphism and its inverse enable us to compute a concept lattice with hedges using algorithms for ordinary concept lattices. We demonstrate by experiments that when selecting various hedges from the strongest to weaker hedges, the reduction in size of the corresponding concept lattices is smooth. From a broader perspective, we argue that linguistic hedges represent mathematically and computationally a feasible way to parameterize methods for knowledge extraction from data that enable one to emphasize or to suppress extracted patterns while keeping their interpretation.

  12. La percolation: un concept unificateur (Percolation a unifying concept)

    NASA Astrophysics Data System (ADS)

    de Gennes, Pierre-Gilles

    It may look surprising (even provoking) at first sight to include an article in French written in "La Recherche" (a French equivalent of "Scientific American"). It is, however, easy to justify this choice in the case of a book dealing with de Gennes' scientific heritage. First, Pierre-Gilles liked to communicate with a large audience (ranging from groups of school children to lectures at the Collège de France) and to share his most recent findings; questions, even areas of ignorance with them. He always did so in simple terms and images for all ages and levels of education. And the use of French allowed more flexibility in this exercise. Secondly, this article is focused on percolation, a concept he invented, independently of Hammersley, in a pioneer article (also in French!) in 1957. Percolation theory led to many applications to disordered matter that de Gennes initiated or stimulated (in numerous articles rather than in a single one). They are described in this seminal paper which can be taken as the fundamental reference article for this chapter dealing with disordered matter…

  13. Systems evaluation of thermal bus concepts

    NASA Technical Reports Server (NTRS)

    Stalmach, D. D.

    1982-01-01

    Thermal bus concepts, to provide a centralized thermal utility for large, multihundred kilowatt space platforms, were studied and the results are summarized. Concepts were generated, defined, and screened for inclusion in system level thermal bus trades. Parametric trade studies were conducted in order to define the operational envelope, performance, and physical characteristics of each. Two concepts were selected as offering the most promise for thermal bus development. All of four concepts involved two phase flow in order to meet the required isothermal nature of the thermal bus. Two of the concepts employ a mechanical means to circulate the working fluid, a liquid pump in one case and a vapor compressor in another. Another concept utilizes direct osmosis as the driving force of the thermal bus. The fourth concept was a high capacity monogroove heat pipe. After preliminary sizing and screening, three of these concepts were selected to carry into the trade studies. The monogroove heat pipe concept was deemed unsuitable for further consideration because of its heat transport limitations. One additional concept utilizing capillary forces to drive the working fluid was added. Parametric system level trade studies were performed. Sizing and weight calculations were performed for thermal bus sizes ranging from 5 to 350 kW and operating temperatures in the range of 4 to 120 C. System level considerations such as heat rejection and electrical power penalties and interface temperature losses were included in the weight calculations.

  14. What's in a Word? Concept mapping: a graphical tool to reinforce learning of epidemiological concepts.

    PubMed

    Berglund, Anita

    2015-12-01

    Epidemiology is founded on central concepts and principles, essential for conducting, reporting and critically assessing epidemiological studies. Definitions of the many concepts used in the field can be found in textbooks and via the Dictionary of Epidemiology. However, central epidemiological concepts are labelled and used in multiple ways, leading to potential misunderstanding when communicating in different fora. The aim here is to describe collaborative concept mapping, and illustrate how it can be used in teaching and learning epidemiology. Concept mapping is a cognitive technique that is widely used in the education of medical and allied health professions as a tool for critical thinking, and to assimilate new knowledge, but it is still under-utilised in epidemiology. A specific concept map is defined by the aim and question in focus; it is thus framed by a context. The concept map is constructed using a set of concepts (nodes) that are linked with arrows or lines (links). Words and phrases (connective terms) are used to explain relationships between the concepts linked. Different domains can be interconnected by linking concepts in different areas (cross-links). The underlying structure of knowledge is often complex, and consequently concept maps can be constructed using different topological features. Here we provide an illustrative example of concept mapping, based on a set of 'basic' concepts introduced in a doctoral course in epidemiology. In summary, concept mapping is a compelling, active learning tool, which can promote shared deeper knowledge of concepts and their complex interconnections, thereby facilitating a better understanding of epidemiological research.

  15. The Europa Clipper mission concept

    NASA Astrophysics Data System (ADS)

    Pappalardo, Robert; Lopes, Rosaly

    Jupiter's moon Europa may be a habitable world. Galileo spacecraft data suggest that an ocean most likely exists beneath Europa’s icy surface and that the “ingredients” necessary for life (liquid water, chemistry, and energy) could be present within this ocean today. Because of the potential for revolutionizing our understanding of life in the solar system, future exploration of Europa has been deemed an extremely high priority for planetary science. A NASA-appointed Science Definition Team (SDT), working closely with a technical team from the Jet Propulsion Laboratory (JPL) and the Applied Physics Laboratory (APL), recently considered options for a future strategic mission to Europa, with the stated science goal: Explore Europa to investigate its habitability. The group considered several mission options, which were fully technically developed, then costed and reviewed by technical review boards and planetary science community groups. There was strong convergence on a favored architecture consisting of a spacecraft in Jupiter orbit making many close flybys of Europa, concentrating on remote sensing to explore the moon. Innovative mission design would use gravitational perturbations of the spacecraft trajectory to permit flybys at a wide variety of latitudes and longitudes, enabling globally distributed regional coverage of the moon’s surface, with nominally 45 close flybys at altitudes from 25 to 100 km. We will present the science and reconnaissance goals and objectives, a mission design overview, and the notional spacecraft for this concept, which has become known as the Europa Clipper. The Europa Clipper concept provides a cost-efficient means to explore Europa and investigate its habitability, through understanding the satellite’s ice and ocean, composition, and geology. The set of investigations derived from these science objectives traces to a notional payload for science, consisting of: Ice Penetrating Radar (for sounding of ice-water interfaces

  16. Concept for Space Technology Advancement

    NASA Astrophysics Data System (ADS)

    Hansen, Jeremiah J.

    2005-02-01

    The space industry is based on an antiquated concept of disposable rockets, earth construction, and non-repairable satellites. Current space vehicle concepts hearken from a time of Cold War animosity and expeditiousness. Space systems are put together in small, single-purpose chunks that are launched with mighty, single-use rockets. Spacecraft need to change to a more versatile, capable, reusable, and mission efficient design. The Crew Exploration Vehicle (CEV) that President Bush put forward in his space initiative on Jan. 14, 2004 is a small first step. But like all first steps, the risk of eventual failure is great without a complementary set of steps, a reliable handhold, and a goal, which are outlined in this paper. The system for space access and development needs to be overhauled to allow for the access to space to complement the building in space, which promotes the production of goods in space, which enhances the exploitation of space resources… and the list goes on. Without supplemental and complementary infrastructure, all political, scientific, and idealistic endeavors to explore and exploit the near solar system will result in quagmires of failures and indecision. Renewed focus on fundamentals, integration, total-system consideration, and solid engineering can avoid catastrophe. Mission success, simple solutions, mission efficiency, and proper testing all seem to have been lost in the chase for the nickels and dimes. These items will increase capabilities available from a system or combination of systems. New propulsion options and materials will enable vehicles previously unachievable. Future spacecraft should exploit modular designs for repeatability and reduced cost. Space construction should use these modular systems on major components built in orbit. All vehicles should apply smart designs and monitoring systems for increased reliability and system awareness. Crew safety systems must use this awareness in alerting the crew, aiding collision

  17. Current Concepts of Maternal Nutrition

    PubMed Central

    Lowensohn, Richard I.; Stadler, Diane D.; Naze, Christie

    2016-01-01

    Background A nutrient-rich maternal diet before and during pregnancy is associated with improved fetal health, more appropriate birth weight, and increased rates of maternal and infant survival. Physicians need a better understanding of the role of diet in shaping fetal outcomes. Given this background, we reviewed and summarized articles on maternal nutrition found in MEDLINE since 1981, written in English, and limited to human subjects. For the Offspring Maternal diets high in sugar and fat lead to an increased incidence of metabolic syndrome, diabetes, and cardiovascular disease later in life. Folic acid should be supplemented prior to conception and continued through at least the first 28 days of fetal life to prevent neural tube defects, and vitamin C should be given to women who smoke to lower the incidence of asthma and wheezing in the children. Iodine deficiency is increasing, and iodine should be included in prenatal supplements. If the maternal hemoglobin is 7 g/dL or more, there is no evidence that iron supplementation is needed. Fish intake during pregnancy is protective against atopic outcomes, whereas high-meat diets contribute to elevated adult blood pressure and hypersecretion of cortisol. For the Mother Calcium supplementation lowers the risk of preeclampsia and hypertensive disease in pregnancy. Conclusions Given the limits of our current knowledge, a diet rich in whole grains, fruits, vegetables, and selected fish is desirable for the best outcomes. Diets high in sugar and fat lead to higher rates of diabetes, metabolic syndrome, and cardiovascular disease. Folic acid, iodine, and calcium in all pregnant women and vitamin C in smokers are the only supplements so far shown to be of value for routine use. The physician treating a pregnant woman should be ready to advise a healthy diet for the benefit of the fetus. Target Audience Obstetricians and gynecologists, family physicians Learning Objectives After participating in this activity, the

  18. Drip Shield Emplacement Gantry Concept

    SciTech Connect

    Silva, R.A.; Cron, J.

    2000-03-29

    This design analysis has shown that, on a conceptual level, the emplacement of drip shields is feasible with current technology and equipment. A plan for drip shield emplacement was presented using a Drip Shield Transporter, a Drip Shield Emplacement Gantry, a locomotive, and a Drip Shield Gantry Carrier. The use of a Drip Shield Emplacement Gantry as an emplacement concept results in a system that is simple, reliable, and interfaces with the numerous other exising repository systems. Using the Waste Emplacement/Retrieval System design as a basis for the drip shield emplacement concept proved to simplify the system by using existing equipment, such as the gantry carrier, locomotive, Electrical and Control systems, and many other systems, structures, and components. Restricted working envelopes for the Drip Shield Emplacement System require further consideration and must be addressed to show that the emplacement operations can be performed as the repository design evolves. Section 6.1 describes how the Drip Shield Emplacement System may use existing equipment. Depending on the length of time between the conclusion of waste emplacement and the commencement of drip shield emplacement, this equipment could include the locomotives, the gantry carrier, and the electrical, control, and rail systems. If the exisiting equipment is selected for use in the Drip Shield Emplacement System, then the length of time after the final stages of waste emplacement and start of drip shield emplacement may pose a concern for the life cycle of the system (e.g., reliability, maintainability, availability, etc.). Further investigation should be performed to consider the use of existing equipment for drip shield emplacement operations. Further investigation will also be needed regarding the interfaces and heat transfer and thermal effects aspects. The conceptual design also requires further design development. Although the findings of this analysis are accurate for the assumptions made

  19. Collaborative interactive visualization: exploratory concept

    NASA Astrophysics Data System (ADS)

    Mokhtari, Marielle; Lavigne, Valérie; Drolet, Frédéric

    2015-05-01

    Dealing with an ever increasing amount of data is a challenge that military intelligence analysts or team of analysts face day to day. Increased individual and collective comprehension goes through collaboration between people. Better is the collaboration, better will be the comprehension. Nowadays, various technologies support and enhance collaboration by allowing people to connect and collaborate in settings as varied as across mobile devices, over networked computers, display walls, tabletop surfaces, to name just a few. A powerful collaboration system includes traditional and multimodal visualization features to achieve effective human communication. Interactive visualization strengthens collaboration because this approach is conducive to incrementally building a mental assessment of the data meaning. The purpose of this paper is to present an overview of the envisioned collaboration architecture and the interactive visualization concepts underlying the Sensemaking Support System prototype developed to support analysts in the context of the Joint Intelligence Collection and Analysis Capability project at DRDC Valcartier. It presents the current version of the architecture, discusses future capabilities to help analyst(s) in the accomplishment of their tasks and finally recommends collaboration and visualization technologies allowing to go a step further both as individual and as a team.

  20. Mars Surface Tunnel Element Concept

    NASA Technical Reports Server (NTRS)

    Rucker, Michelle A.; Jefferies, Sharon; Howe, A. Scott; Howard, Robert; Mary, Natalie; Watson, Judith; Lewis, Ruthan

    2016-01-01

    When the first human visitors on Mars prepare to return to Earth, they will have to comply with stringent planetary protection requirements. Apollo Program experience warns that opening an EVA hatch directly to the surface will bring dust into the ascent vehicle. To prevent inadvertent return of potential Martian contaminants to Earth, careful consideration must be given to the way in which crew ingress their Mars Ascent Vehicle (MAV). For architectures involving more than one surface element-such as an ascent vehicle and a pressurized rover or surface habitat-a retractable tunnel that eliminates extravehicular activity (EVA) ingress is an attractive solution. Beyond addressing the immediate MAV access issue, a reusable tunnel may be useful for other surface applications, such as rover to habitat transfer, once its primary mission is complete. A National Aeronautics and Space Administration (NASA) team is studying the optimal balance between surface tunnel functionality, mass, and stowed volume as part of the Evolvable Mars Campaign (EMC). The study team began by identifying the minimum set of functional requirements needed for the tunnel to perform its primary mission, as this would presumably be the simplest design, with the lowest mass and volume. This Minimum Functional Tunnel then becomes a baseline against which various tunnel design concepts and potential alternatives can be traded, and aids in assessing the mass penalty of increased functionality. Preliminary analysis indicates that the mass of a single-mission tunnel is about 237 kg, not including mass growth allowance.

  1. Concept of Gunshot Wound Spine

    PubMed Central

    Mittal, Radhey Shyam

    2013-01-01

    Gunshot wound (GSW) to the spine which was earlier common in the military population is now being increasingly noted in civilians due to easy availability of firearms of low velocity either licensed or illegal combined with an increased rate of violence in the society. Contributing to 13% to 17% of all spinal injuries, the management of complex injury to the spine produced by a GSW remains controversial. Surgery for spinal cord injuries resulting from low velocity GSWs is reserved for patients with progressive neurologic deterioration, persistent cerebrospinal fluid fistulae, and sometimes for incomplete spinal cord injuries. Surgery may also be indicated to relieve active neural compression from a bullet, bone, intervertebral disk, or a hematoma within the spinal canal. Spinal instability rarely results from a civilian GSW. Cauda equina injuries from low velocity GSWs have a better overall outcome after surgery. In general, the decision to perform surgery should be made on consideration of multiple patient factors that can vary over a period of time. Although there have been plenty of individual case reports regarding GSW to the spine, a thorough review of unique mechanical and biological factors that affect the final outcome has been lacking. We review the key concepts of pathogenesis and management of GSW to the spine and propose an algorithm to guide decision making in such cases. PMID:24353856

  2. Polyherbal formulation: Concept of ayurveda

    PubMed Central

    Parasuraman, Subramani; Thing, Gan Siaw; Dhanaraj, Sokkalingam Arumugam

    2014-01-01

    Ayurveda is one of the traditional medicinal systems of Indian. The philosophy behind Ayurveda is preventing unnecessary suffering and living a long healthy life. Ayurveda involves the use of natural elements to eliminate the root cause of the disease by restoring balance, at the same time create a healthy life-style to prevent the recurrence of imbalance. Herbal medicines have existed world-wide with long recorded history and they were used in ancient Chinese, Greek, Egyptian and Indian medicine for various therapies purposes. World Health Organization estimated that 80% of the word's inhabitants still rely mainly on traditional medicines for their health care. The subcontinent of India is well-known to be one of the major biodiversity centers with about 45,000 plant species. In India, about 15,000 medicinal plants have been recorded, in which the communities used 7,000-7,500 plants for curing different diseases. In Ayurveda, single or multiple herbs (polyherbal) are used for the treatment. The Ayurvedic literature Sarangdhar Samhita’ highlighted the concept of polyherbalism to achieve greater therapeutic efficacy. The active phytochemical constituents of individual plants are insufficient to achieve the desirable therapeutic effects. When combining the multiple herbs in a particular ratio, it will give a better therapeutic effect and reduce the toxicity. This review mainly focuses on important of the polyherbalism and its clinical significance. PMID:25125878

  3. Current NASA lunar base concepts

    NASA Technical Reports Server (NTRS)

    Roberts, Barney B.; Connolly, John F.

    1990-01-01

    The NASA Office of Aeronautics, Exploration, and Technology has completed a Systems Engineering and Integration effort to define a point design for an evolving lunar base that supports substantial science, exploration, and resource production objectives. This study addressed the following: systems level design; element requirements and conceptual design; assessments of precursor and technology needs; and operations concepts. The central base is assumed to be located equatorially on the lunar nearside north of the crater Moltke in Mare Tranquilliatis. The study considers an aggressive case with three main phases. The initial Man-Tended Phase established basic enabling facilities that include a modular habitat that periodically houses a crew of four. During the Experimental Phase, the base becomes permanently manned with the construction of a larger habitat that provides augmented workshop and laboratory volumes and housing for crew. The Operational Phase expands base capabilities to a substantially mature level while reducing reliance on Earth. The analysis classifies base characteristics into several major functional areas: Human Systems; Assembly and Construction; Energy Management; Launch and Landing; Surface Transportation; In-Situ Resources Utilization; User Accommodations; and Telecommunications, Navigation, and Information Management. Results of various NASA-sponsored studies were synthesized to meet requirements. The system level architecture was determined, the physical layout was developed from a set of proximity criteria and related functions, and the evlotuionary path of the base was analyzed. Conclusions include a summary of technology needs, design drivers, high leverage items, and important issues.

  4. Ardhanareeshwara concept: Brain and psychiatry

    PubMed Central

    Raveesh, B. N.

    2013-01-01

    Ardhanareeshvara is a combination of three words “Ardha,” “Nari,” and “Ishwara” means “half,” “woman,” and “lord,” respectively, which when combined means the lord whose half is a woman. It is believed that the God is Lord Shiva and the woman part is his consort Goddess Parvati or Shakti. The Ardhanareeshvara represents a constructive and generative power. Ardhanareeshvara symbolizes male and female principles cannot be separated. It conveys the unity of opposites in the universe. The male half stands for Purusha and female half is Prakriti. Ardhanareeshvara harmonizes the two conflicting ways of life: The spiritual way of the ascetic as represented by Shiva, and the materialistic way of the householder symbolized by Parvati. It conveys that Shiva and Shakti are one and the same. A human being is not a pure unisexual organism. Each human organism bears the potentiality of both male and female sex. Neurohormonal mechanisms have been found to be greatly influencing the sexual behavior. The modern world has come to understand the concept of “Ardhanareeshwara” as it aspires to resolve the paradox of opposites into a unity, not by negation, but through positive experiences of life. The matching of opposites produces the true rhythm of life. PMID:23858265

  5. Mars Climate Sounder (Artist's Concept)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    This artist's concept of NASA's Mars Reconnaissance Orbiter at Mars features one of its instruments -- the Mars Climate Sounder -- in action. Using nine channels across the visible and thermal infrared ranges of the spectrum, the Mars Climate Sounder looks first at space through the atmosphere above the horizon of Mars to get a vertical profile with temperature, pressure, dust and water vapor concentration measurements every 5 kilometers (3 miles) vertically from the ground to about 80 kilometers (about 50 miles) high. It also looks down onto the planet to get surface temperature and column abundances of dust and water vapor between the spacecraft and the surface.

    These 'profiles' and surface measurements are combined into daily, three-dimensional global weather maps for both daytime and nighttime. Observations will be made through the martian year to characterize the large seasonal variations in atmospheric dust loading, humidity and thermal structure, providing scientists with the same type of information meteorologists use to understand and predict weather and climate here on Earth.

  6. Space Solar Power: Satellite Concepts

    NASA Technical Reports Server (NTRS)

    Little, Frank E.

    1999-01-01

    Space Solar Power (SSP) applies broadly to the use of solar power for space related applications. The thrust of the NASA SSP initiative is to develop concepts and demonstrate technology for applying space solar power to NASA missions. Providing power from satellites in space via wireless transmission to a receiving station either on earth, another celestial body or a second satellite is one goal of the SSP initiative. The sandwich design is a satellite design in which the microwave transmitting array is the front face of a thin disk and the back of the disk is populated with solar cells, with the microwave electronics in between. The transmitter remains aimed at the earth in geostationary orbit while a system of mirrors directs sunlight to the photovoltaic cells, regardless of the satellite's orientation to the sun. The primary advantage of the sandwich design is it eliminates the need for a massive and complex electric power management and distribution system for the satellite. However, it requires a complex system for focusing sunlight onto the photovoltaic cells. In addition, positioning the photovoltaic array directly behind the transmitting array power conversion electronics will create a thermal management challenge. This project focused on developing designs and finding emerging technology to meet the challenges of solar tracking, a concentrating mirror system including materials and coatings, improved photovoltaic materials and thermal management.

  7. Rocketdyne RBCC Engine Concept Development

    NASA Technical Reports Server (NTRS)

    Ratckin, G.; Goldman, A.; Ortwerth, P.; Weisberg, S.

    1999-01-01

    Boeing Rocketdyne is pursuing the development of Rocket Based Combined Cycle (RBCC), propulsion systems as demonstrated by significant contract work in the hypersonic arena (ART, NASP, SCT, system studies) and over 12 years of steady company discretionary investment. The Rocketdyne concept is a fixed geometry integrated rocket, ramjet, scramjet which is hydrogen fueled and uses hydrogen regenerative cooling. The baseline engine structural configuration uses an integral structure that eliminates panel seals. seal purge gas, and closeout side attachments. Rocketdyne's experimental RBCC engine (Engine A5) was constructed under contract with the NASA Marshall Space Flight Center. Engine A5 models the complete flight engine flowpath consisting of an inlet, isolator, airbreathing combustor and nozzle. High performance rocket thrusters are integrated into the engine to enable both air-augmented rocket (AAR) and pure rocket operation. Engine A5 was tested in CASL's new FAST facility as an air-augmented rocket, a ramjet and a pure rocket. Measured performance demonstrated vision vehicle performance levels for Mach 3 AAR operation and ramjet operation from Mach 3 to 4. Rocket mode performance was above predictions. For the first time. testing also demonstrated transition from AAR operation to ramjet operation. This baseline configuration has also been shown, in previous testing, to perform well in the scramjet mode.

  8. Generic Airspace Concepts and Research

    NASA Technical Reports Server (NTRS)

    Mogford, Richard H.

    2010-01-01

    The purpose of this study was to evaluate methods for reducing the training and memorization required to manage air traffic in mid-term, Next Generation Air Transportation System (NextGen) airspace. We contrasted the performance of controllers using a sector information display and NextGen automation tools while working with familiar and unfamiliar sectors. The airspace included five sectors from Oakland and Salt Lake City Centers configured as a "generic center" called "West High Center." The Controller Information Tool was used to present essential information for managing these sectors. The Multi Aircraft Control System air traffic control simulator provided data link and conflict detection and resolution. There were five experienced air traffic controller participants. Each was familiar with one or two of the five sectors, but not the others. The participants rotated through all five sectors during the ten data collection runs. The results addressing workload, traffic management, and safety, as well as controller and observer comments, supported the generic sector concept. The unfamiliar sectors were comparable to the familiar sectors on all relevant measures.

  9. Handedness shapes children's abstract concepts.

    PubMed

    Casasanto, Daniel; Henetz, Tania

    2012-03-01

    Can children's handedness influence how they represent abstract concepts like kindness and intelligence? Here we show that from an early age, right-handers associate rightward space more strongly with positive ideas and leftward space with negative ideas, but the opposite is true for left-handers. In one experiment, children indicated where on a diagram a preferred toy and a dispreferred toy should go. Right-handers tended to assign the preferred toy to a box on the right and the dispreferred toy to a box on the left. Left-handers showed the opposite pattern. In a second experiment, children judged which of two cartoon animals looked smarter (or dumber) or nicer (or meaner). Right-handers attributed more positive qualities to animals on the right, but left-handers to animals on the left. These contrasting associations between space and valence cannot be explained by exposure to language or cultural conventions, which consistently link right with good. Rather, right- and left-handers implicitly associated positive valence more strongly with the side of space on which they can act more fluently with their dominant hands. Results support the body-specificity hypothesis (Casasanto, 2009), showing that children with different kinds of bodies think differently in corresponding ways.

  10. The concept of hydrologic landscapes

    USGS Publications Warehouse

    Winter, T.C.

    2001-01-01

    Hydrologic landscapes are multiples or variations of fundamental hydrologic landscape units. A fundamental hydrologic landscape unit is defined on the basis of land-surface form, geology, and climate. The basic land-surface form of a fundamental hydrologic landscape unit is an upland separated from a lowland by an intervening steeper slope. Fundamental hydrologic landscape units have a complete hydrologic system consisting of surface runoff, ground-water flow, and interaction with atmospheric water. By describing actual landscapes in terms of land-surface slope, hydraulic properties of soils and geologic framework, and the difference between precipitation and evapotranspiration, the hydrologic system of actual landscapes can be conceptualized in a uniform way. This conceptual framework can then be the foundation for design of studies and data networks, syntheses of information on local to national scales, and comparison of process research across small study units in a variety of settings. The Crow Wing River watershed in central Minnesota is used as an example of evaluating stream discharge in the context of hydrologic landscapes. Lake-research watersheds in Wisconsin, Minnesota, North Dakota, and Nebraska are used as an example of using the hydrologic-landscapes concept to evaluate the effect of ground water on the degree of mineralization and major-ion chemistry of lakes that lie within ground-water flow systems.

  11. Polyherbal formulation: Concept of ayurveda.

    PubMed

    Parasuraman, Subramani; Thing, Gan Siaw; Dhanaraj, Sokkalingam Arumugam

    2014-07-01

    Ayurveda is one of the traditional medicinal systems of Indian. The philosophy behind Ayurveda is preventing unnecessary suffering and living a long healthy life. Ayurveda involves the use of natural elements to eliminate the root cause of the disease by restoring balance, at the same time create a healthy life-style to prevent the recurrence of imbalance. Herbal medicines have existed world-wide with long recorded history and they were used in ancient Chinese, Greek, Egyptian and Indian medicine for various therapies purposes. World Health Organization estimated that 80% of the word's inhabitants still rely mainly on traditional medicines for their health care. The subcontinent of India is well-known to be one of the major biodiversity centers with about 45,000 plant species. In India, about 15,000 medicinal plants have been recorded, in which the communities used 7,000-7,500 plants for curing different diseases. In Ayurveda, single or multiple herbs (polyherbal) are used for the treatment. The Ayurvedic literature Sarangdhar Samhita' highlighted the concept of polyherbalism to achieve greater therapeutic efficacy. The active phytochemical constituents of individual plants are insufficient to achieve the desirable therapeutic effects. When combining the multiple herbs in a particular ratio, it will give a better therapeutic effect and reduce the toxicity. This review mainly focuses on important of the polyherbalism and its clinical significance.

  12. Polymer concepts in tissue engineering.

    PubMed

    Peter, S J; Miller, M J; Yasko, A W; Yaszemski, M J; Mikos, A G

    1998-01-01

    Traumatic injuries, cancer treatment, and congenital abnormalities are often associated with abnormal bone shape or segmental bone loss. Restoration of normal structure and function in these cases requires replacement of the missing bone that may be accomplished by surgical transfer of natural tissue from an uninjured location elsewhere in the body. However, this procedure is limited by availability, adequate blood supply, and secondary deformities at the donor site. One strategy to overcome these problems is to develop living tissue substitutes based on synthetic biodegradable polymers. Three methods of bone regeneration using biodegradable polymers are being studied in our laboratory: tissue induction, cell transplantation, and fabrication of vascularized bone flaps. Injectable polymers are used for filling skeletal defects and guiding bone tissue growth. Their main advantage is minimizing the surgical intervention or the severity of the surgery. Polymer-cell constructs also hold great promise in the field of tissue engineering. They provide a scaffold on which cells grow and organize themselves. As the cells begin to secrete their own extracellular matrix, the polymer degrades and is eventually eliminated from the body, resulting in completely natural tissue replacement. Bone flaps can be fabricated ectopically into precise shapes and sizes. With an attached vascular supply, these flaps can be transferred into areas deficient in vascularity. This article discusses polymer concepts regarding bone tissue engineering and reviews recent advances of our laboratory on guided bone regeneration using biodegradable polymer scaffolds.

  13. The folk conception of knowledge.

    PubMed

    Starmans, Christina; Friedman, Ori

    2012-09-01

    How do people decide which claims should be considered mere beliefs and which count as knowledge? Although little is known about how people attribute knowledge to others, philosophical debate about the nature of knowledge may provide a starting point. Traditionally, a belief that is both true and justified was thought to constitute knowledge. However, philosophers now agree that this account is inadequate, due largely to a class of counterexamples (termed "Gettier cases") in which a person's justified belief is true, but only due to luck. We report four experiments examining the effect of truth, justification, and "Gettiering" on people's knowledge attributions. These experiments show that: (1) people attribute knowledge to others only when their beliefs are both true and justified; (2) in contrast to contemporary philosophers, people also attribute knowledge to others in Gettier situations; and (3) knowledge is not attributed in one class of Gettier cases, but only because the agent's belief is based on "apparent" evidence. These findings suggest that the lay concept of knowledge is roughly consistent with the traditional account of knowledge as justified true belief, and also point to a major difference between the epistemic intuitions of laypeople and those of philosophers.

  14. A Methodology for Developing Diagnostic Concept Inventories

    NASA Astrophysics Data System (ADS)

    Lindell, Rebecca

    2006-12-01

    Since the development of the Force Concept Inventory, there as been a heightened interest in developing other concept inventories that not only assess if students understand a phenomena, but also diagnose specific alternative understandings. Unfortunately, there is no clear-cut methodology on how to construct such inventories. One of the difficulties is that only some parts of test development theory are appropriate for such concept inventories. This is due to the concept inventories being distracter driven, where test-takers do not randomly choose an incorrect answer. In this poster, I will present a methodology for developing diagnostic concept inventories, which combines traditional psychometric theory with modern theories of concentration and model analysis. An example of how this methodology was utilized to develop the successful Lunar Phases Concept Inventory (LPCI) will also be given.

  15. Regionally Aligned Forces: Concept Viability and Implementation

    DTIC Science & Technology

    2015-03-01

    Carlisle Compendia of Collaborative Research United States Army War College Student Publications Regionally Aligned Forces: Concept Viability and...Concept Viability and Implementation 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER...Carlisle Compendia of Collaborative Research United States Army War College Student Publications Regionally Aligned Forces: Concept Viability and

  16. Deep understanding of electromagnetism using crosscutting concepts

    NASA Astrophysics Data System (ADS)

    De Poorter, John; De Lange, Jan; Devoldere, Lies; Van Landeghem, Jouri; Strubbe, Katrien

    2017-01-01

    Crosscutting concepts like patterns and models are fundamental parts in both the American framework of science education (from the AAAS) and our proposals for a new science education framework in Flanders. These concepts deepen the insight of both students and teachers. They help students to ask relevant questions during an inquiry and they give an understanding in how scientists built up their scientific theories. We illustrate the didactical possibilities of crosscutting concepts within the field of electromagnetism.

  17. Making sense of competing nursing shortage concepts.

    PubMed

    Goldfarb, Marsha G; Goldfarb, Robert S; Long, Mark C

    2008-08-01

    Widespread and continuing discussions of nursing shortages frequently involve divergent concepts of shortage that can have differing policy implications. This article explains the shortage concepts used by economists, hospital administrators, and government policy makers. It discusses measurement problems and suggests possible improvements. It then sets forth the divergent policy implications of competing shortage concepts. The article's aim is to promote greater clarity in analyses of nursing shortages and more fruitful conversations among participants who use different notions of shortages.

  18. Concept mapping: a road to critical thinking.

    PubMed

    St Cyr, Sheila K; All, Anita C

    2009-01-01

    Graduate nurses entering the workforce today are, at times, lacking in the area of critical thinking. Giving graduate nurses a concept map would provide a tool to guide their critical thinking until it becomes inherent or second nature. The concept map, a graphic illustration of key points, guides the focus of patient problems using a body system approach. This article details the use of a concept map in the application of knowledge to practice.

  19. Advanced LMMHD space power generation concept

    NASA Astrophysics Data System (ADS)

    Ho, Vincent; Wong, Albert; Kim, Kilyoo; Dhir, Vijay

    Magnetohydrodynamic (MHD) power generation concept has been proposed and studied worldwide as one of the future power generation sources. An advanced one fluid two phase liquid metal (LM) MHD power generation concept was developed for space nuclear power generation design. The concept employs a nozzle to accelerate the liquid metal coolant to an acceptable velocity with Mach number greater than unity. Such nozzle and the MHD power generator replace the turbogenerator of a high temperature Rankine turboelectric cycle concept. As a result, the power generation system contains no movable parts. This provides high reliability, which is a very important factor in space application.

  20. Titan In Situ Exploration Concepts at JPL

    NASA Technical Reports Server (NTRS)

    Elliott, John O.; Hall, Jeffery L.; Jones, Jack; Reh, Kim

    2008-01-01

    This slide presentation reviews concepts for exploring Titan via balloon vehicles. The presentation includes information about the baseline options, the deployment scenario, and the balloon technology development.

  1. Reintroducing the Concept of Complementarity into Psychology.

    PubMed

    Wang, Zheng; Busemeyer, Jerome

    2015-01-01

    Central to quantum theory is the concept of complementarity. In this essay, we argue that complementarity is also central to the emerging field of quantum cognition. We review the concept, its historical roots in psychology, and its development in quantum physics and offer examples of how it can be used to understand human cognition. The concept of complementarity provides a valuable and fresh perspective for organizing human cognitive phenomena and for understanding the nature of measurements in psychology. In turn, psychology can provide valuable new evidence and theoretical ideas to enrich this important scientific concept.

  2. Reintroducing the Concept of Complementarity into Psychology

    PubMed Central

    Wang, Zheng; Busemeyer, Jerome

    2015-01-01

    Central to quantum theory is the concept of complementarity. In this essay, we argue that complementarity is also central to the emerging field of quantum cognition. We review the concept, its historical roots in psychology, and its development in quantum physics and offer examples of how it can be used to understand human cognition. The concept of complementarity provides a valuable and fresh perspective for organizing human cognitive phenomena and for understanding the nature of measurements in psychology. In turn, psychology can provide valuable new evidence and theoretical ideas to enrich this important scientific concept. PMID:26640454

  3. Relativity concept inventory: Development, analysis, and results

    NASA Astrophysics Data System (ADS)

    Aslanides, J. S.; Savage, C. M.

    2013-06-01

    We report on a concept inventory for special relativity: the development process, data analysis methods, and results from an introductory relativity class. The Relativity Concept Inventory tests understanding of relativistic concepts. An unusual feature is confidence testing for each question. This can provide additional information; for example, high confidence correlated with incorrect answers suggests a misconception. A novel aspect of our data analysis is the use of Monte Carlo simulations to determine the significance of correlations. This approach is particularly useful for small sample sizes, such as ours. Our results show a gender bias that was not present in course assessment, similar to that reported for the Force Concept Inventory.

  4. A Tangible Approach to Concept Mapping

    NASA Astrophysics Data System (ADS)

    Tanenbaum, Karen; Antle, Alissa N.

    2009-05-01

    The Tangible Concept Mapping project investigates using a tangible user interface to engage learners in concept map creation. This paper describes a prototype implementation of the system, presents some preliminary analysis of its ease of use and effectiveness, and discusses how elements of tangible interaction support concept mapping by helping users organize and structure their knowledge about a domain. The role of physical engagement and embodiment in supporting the mental activity of creating the concept map is explored as one of the benefits of a tangible approach to learning.

  5. Study of alternate space shuttle concepts

    NASA Technical Reports Server (NTRS)

    1971-01-01

    A study of alternate space shuttle concepts was conducted to examine the stage-and-one-half concept and its potential for later conversion and use in the two stage reusable shuttle system. A study of external hydrogen tank concepts was conducted to determine the issues involved in the design and production of a low-cost expendable tank system. The major objectives of the study were to determine: (1) realistic drop tank program cost estimates, (2) estimated drop tank program cost for selected specific designs, and (3) change in program cost due to variations in design and manufacturing concepts and changes in program assumptions.

  6. Children's understanding of addition and subtraction concepts.

    PubMed

    Robinson, Katherine M; Dubé, Adam K

    2009-08-01

    After the onset of formal schooling, little is known about the development of children's understanding of the arithmetic concepts of inversion and associativity. On problems of the form a+b-b (e.g., 3+26-26), if children understand the inversion concept (i.e., that addition and subtraction are inverse operations), then no calculations are needed to solve the problem. On problems of the form a+b-c (e.g., 3+27-23), if children understand the associativity concept (i.e., that the addition and subtraction can be solved in any order), then the second part of the problem can be solved first. Children in Grades 2, 3, and 4 solved both types of problems and then were given a demonstration of how to apply both concepts. Approval of each concept and preference of a conceptual approach versus an algorithmic approach were measured. Few grade differences were found on either task. Conceptual understanding was greater for inversion than for associativity on both tasks. Clusters of participants in all grades showed that some had strong understanding of both concepts, some had strong understanding of the inversion concept only, and others had weak understanding of both concepts. The findings highlight the lack of developmental increases and the large individual differences in conceptual understanding on two arithmetic concepts during the early school years.

  7. Collision Avoidance for Airport Traffic Concept Evaluation

    NASA Technical Reports Server (NTRS)

    Jones, Denise R.; Prinzel, Lawrence J., III; Otero, Sharon D.; Barker, Glover D.

    2009-01-01

    An initial Collision Avoidance for Airport Traffic (CAAT) concept for the Terminal Maneuvering Area (TMA) was evaluated in a simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center. CAAT is being designed to enhance surface situation awareness and provide cockpit alerts of potential conflicts during runway, taxi, and low altitude air-to-air operations. The purpose of the study was to evaluate the initial concept for an aircraft-based method of conflict detection and resolution (CD&R) in the TMA focusing on conflict detection algorithms and alerting display concepts. This paper gives an overview of the CD&R concept, simulation study, and test results.

  8. Proving the Ocean Nourishment Concept

    NASA Astrophysics Data System (ADS)

    Jones, I. S.

    2007-12-01

    Vast regions of the sea are barren because of a lack of essential nutrients. Ocean Nourishment is the concept of injecting nutrients into the photic zone of the ocean to store carbon and increase the base of the marine food web. It is elaborated in Jones & Young (1997). The first step in demonstrating this concept is to see if the limiting nutrients can be recognised and provided to the oligotrophic ocean. To this end water samples from three sites were collected in ultraclean polycarbonate culture bottles and enriched with various mixtures of nutrients. They were then placed in a water bath and subjected to natural sunlight for a number of days. Fluorescence levels were measured daily. Previously Thomas (1969) carried out enrichment experiments in and out of high nutrient water in the North Pacific and again Thomas (1970) cultured on the deck of his ship nutrient poor waters in the Pacific. He found nitrogen was the most important limiting nutrient in the poor waters but that micronutrients produced growth in the nutrient rich waters. Ryther and Dunstan (1971) in the Atlantic cultured coastal water with only nitrogen and phosphorus separately. The addition of nitrogen without phosphate produced growth in all cases. To increase the geographic coverage of enrichment experiments, samples were collected off Morocco twice, in the Tasman Sea and in the Sulu Sea. The samples enriched with different concentrations of urea (typically 10 microM) and phosphorous. An increase concentration of chlorophyll is the result of growth of phytoplankton exceeding death and grazing by zooplankton. At five sites an increase of chlorophyll was observed in the macronutrient enriched bottles over that in the control. At the sixth site the control grew at much the same rate as the enriched sample possibly due to contamination by the fluorometer. The maximum chlorophyll level was observed after 4 or 5 days. Replicate samples showed different levels of chlorophyll growths. It was concluded

  9. Learning Styles: Concepts and Evidence.

    PubMed

    Pashler, Harold; McDaniel, Mark; Rohrer, Doug; Bjork, Robert

    2008-12-01

    The term "learning styles" refers to the concept that individuals differ in regard to what mode of instruction or study is most effective for them. Proponents of learning-style assessment contend that optimal instruction requires diagnosing individuals' learning style and tailoring instruction accordingly. Assessments of learning style typically ask people to evaluate what sort of information presentation they prefer (e.g., words versus pictures versus speech) and/or what kind of mental activity they find most engaging or congenial (e.g., analysis versus listening), although assessment instruments are extremely diverse. The most common-but not the only-hypothesis about the instructional relevance of learning styles is the meshing hypothesis, according to which instruction is best provided in a format that matches the preferences of the learner (e.g., for a "visual learner," emphasizing visual presentation of information). The learning-styles view has acquired great influence within the education field, and is frequently encountered at levels ranging from kindergarten to graduate school. There is a thriving industry devoted to publishing learning-styles tests and guidebooks for teachers, and many organizations offer professional development workshops for teachers and educators built around the concept of learning styles. The authors of the present review were charged with determining whether these practices are supported by scientific evidence. We concluded that any credible validation of learning-styles-based instruction requires robust documentation of a very particular type of experimental finding with several necessary criteria. First, students must be divided into groups on the basis of their learning styles, and then students from each group must be randomly assigned to receive one of multiple instructional methods. Next, students must then sit for a final test that is the same for all students. Finally, in order to demonstrate that optimal learning requires

  10. Ayurvedic concepts related to psychotherapy.

    PubMed

    Behere, Prakash B; Das, Anweshak; Yadav, Richa; Behere, Aniruddh P

    2013-01-01

    The perfect balance of mind, body and soul is considered as complete health in Ayurveda. Ayurveda has its own identity as most ancient and traditional System of Medicine in India. Even Ayurveda emphasizes its treatment modalities into three parts viz. Satwawajay Chikitsa, Yuktivyapashray and Daivyapashray Chikitsa. Sattvavajaya therapy mentioned in Charakasamhita and it used as new concept of psychotherapy in Ayurveda. The effectiveness of "traditional mental health promoting practices" was identified as health regimens (swasthvrtt), correct behavior (sadvrtt), and yoga. Sattvavajaya as psychotherapy, is the mental restraint, or a "mind control" as referred by Caraka, is achieved through "spiritual knowledge, philosophy, fortitude, remembrance and concentration. Ayurvedic psychotherapy would play a dual role: First, as a revival of authentic medical culture, the exercise of a practice with an assumed primordial dimension, and second as a discovery of authentic subjectivity, the revelation of a self with an assumed interior depth. When we integrate the contemporary art of psychotherapy with the ancient science of Ayurveda, it becomes a powerful combination that is called Psycho Veda. The integration of Psycho and Veda is motivated by the complete integration of the immense but fairly contemporary view of the mind, emotions and psyche and how this performs in our lives. Integrating Psychotherapy and Vedic principles teaches us how to rediscover critical knowledge and awareness of the natural forces and rhythms that compliment and strengthen our human experience, through the understanding of the psyche and what our inner experiences are and also involving practical daily activities with thorough attention to our total environment to bring about radical changes in our mental outlook and in physical health.

  11. Ayurvedic concepts related to psychotherapy

    PubMed Central

    Behere, Prakash B.; Das, Anweshak; Yadav, Richa; Behere, Aniruddh P.

    2013-01-01

    The perfect balance of mind, body and soul is considered as complete health in Ayurveda. Ayurveda has its own identity as most ancient and traditional System of Medicine in India. Even Ayurveda emphasizes its treatment modalities into three parts viz. Satwawajay Chikitsa, Yuktivyapashray and Daivyapashray Chikitsa. Sattvavajaya therapy mentioned in Charakasamhita and it used as new concept of psychotherapy in Ayurveda. The effectiveness of “traditional mental health promoting practices” was identified as health regimens (swasthvrtt), correct behavior (sadvrtt), and yoga. Sattvavajaya as psychotherapy, is the mental restraint, or a “mind control” as referred by Caraka, is achieved through “spiritual knowledge, philosophy, fortitude, remembrance and concentration. Ayurvedic psychotherapy would play a dual role: First, as a revival of authentic medical culture, the exercise of a practice with an assumed primordial dimension, and second as a discovery of authentic subjectivity, the revelation of a self with an assumed interior depth. When we integrate the contemporary art of psychotherapy with the ancient science of Ayurveda, it becomes a powerful combination that is called Psycho Veda. The integration of Psycho and Veda is motivated by the complete integration of the immense but fairly contemporary view of the mind, emotions and psyche and how this performs in our lives. Integrating Psychotherapy and Vedic principles teaches us how to rediscover critical knowledge and awareness of the natural forces and rhythms that compliment and strengthen our human experience, through the understanding of the psyche and what our inner experiences are and also involving practical daily activities with thorough attention to our total environment to bring about radical changes in our mental outlook and in physical health. PMID:23858273

  12. Hubble Space Telescope-Concept

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This is an artist's concept of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  13. Basic concepts in plasma accelerators.

    PubMed

    Bingham, Robert

    2006-03-15

    In this article, we present the underlying physics and the present status of high gradient and high-energy plasma accelerators. With the development of compact short pulse high-brightness lasers and electron and positron beams, new areas of studies for laser/particle beam-matter interactions is opening up. A number of methods are being pursued vigorously to achieve ultra-high-acceleration gradients. These include the plasma beat wave accelerator (PBWA) mechanism which uses conventional long pulse ( approximately 100 ps) modest intensity lasers (I approximately 10(14)-10(16) W cm(-2)), the laser wakefield accelerator (LWFA) which uses the new breed of compact high-brightness lasers (<1 ps) and intensities >10(18) W cm(-2), self-modulated laser wakefield accelerator (SMLWFA) concept which combines elements of stimulated Raman forward scattering (SRFS) and electron acceleration by nonlinear plasma waves excited by relativistic electron and positron bunches the plasma wakefield accelerator. In the ultra-high intensity regime, laser/particle beam-plasma interactions are highly nonlinear and relativistic, leading to new phenomenon such as the plasma wakefield excitation for particle acceleration, relativistic self-focusing and guiding of laser beams, high-harmonic generation, acceleration of electrons, positrons, protons and photons. Fields greater than 1 GV cm(-1) have been generated with monoenergetic particle beams accelerated to about 100 MeV in millimetre distances recorded. Plasma wakefields driven by both electron and positron beams at the Stanford linear accelerator centre (SLAC) facility have accelerated the tail of the beams.

  14. Concepts and Relations in Neurally Inspired In Situ Concept-Based Computing

    PubMed Central

    van der Velde, Frank

    2016-01-01

    In situ concept-based computing is based on the notion that conceptual representations in the human brain are “in situ.” In this way, they are grounded in perception and action. Examples are neuronal assemblies, whose connection structures develop over time and are distributed over different brain areas. In situ concepts representations cannot be copied or duplicated because that will disrupt their connection structure, and thus the meaning of these concepts. Higher-level cognitive processes, as found in language and reasoning, can be performed with in situ concepts by embedding them in specialized neurally inspired “blackboards.” The interactions between the in situ concepts and the blackboards form the basis for in situ concept computing architectures. In these architectures, memory (concepts) and processing are interwoven, in contrast with the separation between memory and processing found in Von Neumann architectures. Because the further development of Von Neumann computing (more, faster, yet power limited) is questionable, in situ concept computing might be an alternative for concept-based computing. In situ concept computing will be illustrated with a recently developed BABI reasoning task. Neurorobotics can play an important role in the development of in situ concept computing because of the development of in situ concept representations derived in scenarios as needed for reasoning tasks. Neurorobotics would also benefit from power limited and in situ concept computing. PMID:27242504

  15. Concepts and Relations in Neurally Inspired In Situ Concept-Based Computing.

    PubMed

    van der Velde, Frank

    2016-01-01

    In situ concept-based computing is based on the notion that conceptual representations in the human brain are "in situ." In this way, they are grounded in perception and action. Examples are neuronal assemblies, whose connection structures develop over time and are distributed over different brain areas. In situ concepts representations cannot be copied or duplicated because that will disrupt their connection structure, and thus the meaning of these concepts. Higher-level cognitive processes, as found in language and reasoning, can be performed with in situ concepts by embedding them in specialized neurally inspired "blackboards." The interactions between the in situ concepts and the blackboards form the basis for in situ concept computing architectures. In these architectures, memory (concepts) and processing are interwoven, in contrast with the separation between memory and processing found in Von Neumann architectures. Because the further development of Von Neumann computing (more, faster, yet power limited) is questionable, in situ concept computing might be an alternative for concept-based computing. In situ concept computing will be illustrated with a recently developed BABI reasoning task. Neurorobotics can play an important role in the development of in situ concept computing because of the development of in situ concept representations derived in scenarios as needed for reasoning tasks. Neurorobotics would also benefit from power limited and in situ concept computing.

  16. Concept for Underground Disposal of Nuclear Waste

    NASA Technical Reports Server (NTRS)

    Bowyer, J. M.

    1987-01-01

    Packaged waste placed in empty oil-shale mines. Concept for disposal of nuclear waste economically synergistic with earlier proposal concerning backfilling of oil-shale mines. New disposal concept superior to earlier schemes for disposal in hard-rock and salt mines because less uncertainty about ability of oil-shale mine to contain waste safely for millenium.

  17. Total Energy Concepts as Applied to Universities.

    ERIC Educational Resources Information Center

    Gudgeon, R.L.

    A comprehensive discussion of single fuel source generation of power and heating requirements is presented. Definition and explanation of system concepts includes--(1) heat pumps, (2) steam turbines, (3) gas turbines, and (4) gas and diesel engines. Concept cost evaluation factors described are--(1) load pattern, (2) campus configuration, (3) fuel…

  18. Do We Need a Concept of Culture?

    ERIC Educational Resources Information Center

    Jahoda, Gustav

    1984-01-01

    Rohner's analysis of the concept of culture is examined, considering in particular, his distinction between culture and social systems. His view is contrasted with that of Segall, who regards the concept of "culture" as redundant for cross-cultural psychology. It is argued that neither position is adequate, and possible resolutions are offered.…

  19. Unified Technical Concepts. Application Modules Volume II.

    ERIC Educational Resources Information Center

    Center for Occupational Research and Development, Inc., Waco, TX.

    Unified Technical Concepts (UTC) is a modular system for teaching applied physics in two-year postsecondary technician programs. This UTC laboratory textbook, the second of two volumes, consists of 45 learning modules dealing with basic concepts of physics. Addressed in the individual chapters of the guide are the following topics: force…

  20. Some Student Conceptions of Electromagnetic Induction

    ERIC Educational Resources Information Center

    Thong, Wai Meng; Gunstone, Richard

    2008-01-01

    Introductory electromagnetism is a central part of undergraduate physics. Although there has been some research into student conceptions of electromagnetism, studies have been sparse and separated. This study sought to explore second year physics students' conceptions of electromagnetism, to investigate to what extent the results from the present…

  1. A Cognitive Approach to Threshold Concepts

    ERIC Educational Resources Information Center

    Walker, Guy

    2013-01-01

    This paper asks a fundamental question: what is happening inside the mind of the undergraduate during teaching and learning experiences, and how should curricula be designed to support it? A number of concepts lend themselves to providing an answer, principle among which is the relatively recent idea of Threshold Concepts. In this paper we attempt…

  2. Concept Maps as Tools for Teaching.

    ERIC Educational Resources Information Center

    Moreira, Marco A.

    1979-01-01

    Discusses how concept maps with two dimensional diagrams which show hierarchical relationships among concepts of a discipline can be used in teaching physics. An example for teaching a course in electromagnetism at the Federal University of Rio Grande do Sul, Brazil is presented. (HM)

  3. Advanced sunflower antenna concept development. [stowable reflectors

    NASA Technical Reports Server (NTRS)

    Archer, J. S.

    1980-01-01

    The feasibility of stowing large solid antenna reflectors in the shuttle was demonstrated for applications with 40 foot apertures at frequencies of 100 GHz. Concepts allowing extension of the basic concept to 80-foot apertures operable at 60 GHz were identified.

  4. Threshold Concepts, Systems and Learning for Sustainability

    ERIC Educational Resources Information Center

    Sandri, Orana Jade

    2013-01-01

    This paper presents a framework for understanding the role that systems theory might play in education for sustainability (EfS). It offers a sketch and critique of Land and Meyer's notion of a "threshold concept", to argue that seeing systems as a threshold concept for sustainability is useful for understanding the processes of…

  5. Advanced instrumentation concepts for environmental control subsystems

    NASA Technical Reports Server (NTRS)

    Yang, P. Y.; Schubert, F. H.; Gyorki, J. R.; Wynveen, R. A.

    1978-01-01

    Design, evaluation and demonstration of advanced instrumentation concepts for improving performance of manned spacecraft environmental control and life support systems were successfully completed. Concepts to aid maintenance following fault detection and isolation were defined. A computer-guided fault correction instruction program was developed and demonstrated in a packaged unit which also contains the operator/system interface.

  6. Teaching Striking/Fielding Concepts in Cricket

    ERIC Educational Resources Information Center

    Turner, Adrian P.

    2004-01-01

    This article presents activities for developing striking/fielding concepts in modified cricket games. Though not as familiar to American children, cricket is emerging as the second (to soccer) most popular game in the world. The novelty of the skills provides an appropriate learning challenge for all students while reinforcing concepts and…

  7. Concept Mapping with Multimedia on the Web.

    ERIC Educational Resources Information Center

    Alpert, Sherman R.; Gruenberg, Keith

    2000-01-01

    Discusses concept maps and describes an extension to computer-based concept mapping tools that provides representational capabilities that allows students to express their knowledge more fully by incorporating dynamic media-sound, video, and animated images. Explains multimedia knowledge maps, accessibility via Web browsers, and possible future…

  8. Adolescents' Conceptions of Ability and Intelligence.

    ERIC Educational Resources Information Center

    Nicholls, John G.

    Adolescents' developing sense of competence is based on two domains, ability and intelligence. Intelligence testing generally presumes a conception of ability as current capacity that limits the extent to which effort can improve performance. Conceptions of intelligence, and other skills, involve implications about the nature of different forms of…

  9. Externalising Students' Mental Models through Concept Maps

    ERIC Educational Resources Information Center

    Chang, Shu-Nu

    2007-01-01

    The purpose of this study is to use concept maps as an "expressed model" to investigate students' mental models regarding the homeostasis of blood sugar. The difficulties in learning the concept of homeostasis and in probing mental models have been revealed in many studies. Homeostasis of blood sugar is one of the themes in junior high…

  10. Statistics Poker: Reinforcing Basic Statistical Concepts

    ERIC Educational Resources Information Center

    Leech, Nancy L.

    2008-01-01

    Learning basic statistical concepts does not need to be tedious or dry; it can be fun and interesting through cooperative learning in the small-group activity of Statistics Poker. This article describes a teaching approach for reinforcing basic statistical concepts that can help students who have high anxiety and makes learning and reinforcing…

  11. Improved Self-Concepts Through Visual Communication.

    ERIC Educational Resources Information Center

    Gill, Walter Arthur

    Investigations linking communication media experiences and self-concepts suggest that changes in the self-concept of Afro-American students may be acutely affected in instructional environments through group activities employing mediated approaches, participation in the media as producers rather than consumers, and instruction through visual…

  12. THE DEVELOPMENT OF A CONCEPT OF EMPATHY.

    ERIC Educational Resources Information Center

    STOHRER, JOHN F.

    THIS PAPER DISCUSSES EMPATHY AS THE CONCEPT HAS DEVELOPED PHILOSOPHICALLY, AS IT IS USED IN THE ARTS, AND AS IT DIFFERS FROM SYMPATHY. EMPATHY IS DEFINED AS A TWO-DIRECTIONAL PROCESS INVOLVING THE OBSERVER AND THE OBSERVED. THE ETHICAL CONCEPT IS DEFINED AS AN EMOTIONAL "FEELING INTO," EXTENSION, OR INVESTMENT OF THE SELF ON THE PART OF…

  13. Children's Understanding of Addition and Subtraction Concepts

    ERIC Educational Resources Information Center

    Robinson, Katherine M.; Dube, Adam K.

    2009-01-01

    After the onset of formal schooling, little is known about the development of children's understanding of the arithmetic concepts of inversion and associativity. On problems of the form a+b-b (e.g., 3+26-26), if children understand the inversion concept (i.e., that addition and subtraction are inverse operations), then no calculations are needed…

  14. Applying Threshold Concepts to Finance Education

    ERIC Educational Resources Information Center

    Hoadley, Susan; Wood, Leigh N.; Tickle, Leonie; Kyng, Tim

    2016-01-01

    Purpose: The purpose of this paper is to investigate and identify threshold concepts that are the essential conceptual content of finance programmes. Design/Methodology/Approach: Conducted in three stages with finance academics and students, the study uses threshold concepts as both a theoretical framework and a research methodology. Findings: The…

  15. Student Teachers' Conceptions of Teaching Biology

    ERIC Educational Resources Information Center

    Subramaniam, Karthigeyan

    2014-01-01

    The purpose of this qualitative study was to investigate prospective biology teachers' conceptions of teaching biology and identify how these conceptions revealed their strategies for helping their future students' learning of biology. The study utilized drawings, narratives and interviews to investigate the nature of the prospective biology…

  16. The concept exploration model and an application

    NASA Astrophysics Data System (ADS)

    Zhang, Yin; Gao, Kening; Zhang, Bin

    2015-03-01

    For a user who is unfamiliar with a target domain, the first step to conduct an exploratory search task is to go over a learning phrase, which means to learn from the search results to acquire basic domain knowledge. Since lots of search results could be returned by a search engine, and usually only a small portion of all the results contain valuable knowledge to the current search task, the user usually needs to read lots of documents and could only learn limited knowledge. This makes the learning phrase a low efficiency, time consuming and easy to fail process. In order to support the learning phrase of the exploratory search process, this paper proposes the concept exploration model which describes how a user reads search results and figures out interesting concepts. The model focuses on how does a user explore related concepts during the learning phrase, and factorizes the concept exploration process as a production of the probability that concepts form a specific relation structure, and the probability that a user is attracted by a concept. In an application example, the concept exploration model is used in a query recommendation task to support exploratory search. We demonstrate how to determine the two probabilistic factors and evaluate the model with a set of metrics. The experiment results show that the application example could help users explore domain concepts more effectively.

  17. Nursing image: an evolutionary concept analysis.

    PubMed

    Rezaei-Adaryani, Morteza; Salsali, Mahvash; Mohammadi, Eesa

    2012-12-01

    A long-term challenge to the nursing profession is the concept of image. In this study, we used the Rodgers' evolutionary concept analysis approach to analyze the concept of nursing image (NI). The aim of this concept analysis was to clarify the attributes, antecedents, consequences, and implications associated with the concept. We performed an integrative internet-based literature review to retrieve English literature published from 1980-2011. Findings showed that NI is a multidimensional, all-inclusive, paradoxical, dynamic, and complex concept. The media, invisibility, clothing style, nurses' behaviors, gender issues, and professional organizations are the most important antecedents of the concept. We found that NI is pivotal in staff recruitment and nursing shortage, resource allocation to nursing, nurses' job performance, workload, burnout and job dissatisfaction, violence against nurses, public trust, and salaries available to nurses. An in-depth understanding of the NI concept would assist nurses to eliminate negative stereotypes and build a more professional image for the nurse and the profession.

  18. Ecological site concepts for the Caldenal ecoregion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecological site (ES) concepts describe potential vegetation and ecological mechanisms of plant community change within specific soil, geomorphic and climate conditions. In this study, a preliminary definition of ES concepts for the caldenal ecoregion was developed by exploring the relationship betw...

  19. THE CONCEPTS OF OVER- AND UNDERACHIEVEMENT.

    ERIC Educational Resources Information Center

    THORNDIKE, ROBERT L.

    THIS MONOGRAPH WAS WRITTEN FOR EDUCATORS INTERESTED IN INITIATING RESEARCH STUDIES ON UNDERACHIEVEMENT AND OVERACHIEVEMENT. DEFECTIVE EXPERIMENTAL PLANNING, INHERENT DEFICIENCIES IN CONCEPT DEFINITION, AND OTHER FACTORS RESULTING IN FACULTY RESEARCH DESIGN RENDER MANY RESEARCH FINDINGS IN THIS AREA INCONCLUSIVE OR MISLEADING. THE CONCEPTS OF…

  20. An Annotated Bibliography of Concept Mapping

    ERIC Educational Resources Information Center

    Garcia, GNA

    2008-01-01

    A rich narrative-style bibliography of concept mapping (reviewing six articles published between 1992-2005). Articles reviewed include: (1) Cognitive mapping: A qualitative research method for social work (C. Bitoni); (2) Collaborative concept mapping: Provoking and supporting meaningful discourse (C. Boxtel, J. Linden, E. Roelofs, and G. Erkens);…