WorldWideScience

Sample records for solar spectroheliograph consisting

  1. Imaging sunlight using a digital spectroheliograph

    CERN Document Server

    Harrison, Ken M

    2016-01-01

    Ken M. Harrison's latest book is a complete guide for amateur astronomers who want to obtain detailed narrowband images of the Sun using a digital spectroheliograph (SHG). The SHG allows the safe imaging of the Sun without the expense of commercial ‘etalon’ solar filters. As the supporting software continues to be refined, the use of the digital spectroheliograph will become more and more mainstream and has the potential to replace the expensive solar filters currently in use. The early chapters briefly explain the concept of the SHG and how it can produce an image from the solar spectrum. A comparison of the currently available narrow band solar filters is followed by a detailed analysis of the critical design, construction and assembly features of the SHG. The design and optimum layout of the instrument is discussed to allow evaluation of performance. This information explains how to assemble a fully functional SHG using readily available components. The software required to process the images is exp...

  2. Using X-ray spectroheliograph technique for investigations of laser-produced plasma under interaction with strong magnetic field

    International Nuclear Information System (INIS)

    Faenov, A.; Dyakin, V.; Magunov, A.; Pikuz, T.; Skobelev, I.; Pikuz, S.; Pisarczyk, T.; Wolowski, J.; Zielinska, E.

    1996-01-01

    A dense jet of a plasma consisting of multiply charged ions was generated in the interaction of a laser plasma with a strong external axial magnetic field. It is shown that using the high-luminosity X-ray spectroheliograph technique allows to measure plasma emission spectra with 2-dimensional spatial resolution even in the cases when these spectra have small intensities. The X-ray spectroscopy and interferometry methods are used to measure plasma parameter distributions. The dependencies of N e (z) and T e (z) measured in this paper can be used to calculate the evolution of plasma ionization state during plasma expansion. The quasihomogeneous laser jet, which appears when a laser plasma interacts with an external magnetic field can be used not only to form an active medium of a short wavelength laser, but probably also to tackle the urgent problem of transport in a laser ion injector. (orig.)

  3. Using X-ray spectroheliograph technique for investigations of laser-produced plasma under interaction with strong magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Faenov, A. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Dyakin, V. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Magunov, A. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Pikuz, T. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Skobelev, I. [MISDC of VNIIFTRI, Mendeleevo (Russian Federation); Pikuz, S. [Rossijskaya Akademiya Nauk, Moscow (Russian Federation). Fizicheskij Inst.; Kasperczyk, A. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Pisarczyk, T. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Wolowski, J. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland); Zielinska, E. [Institute of Plasma Physics and Laser Microfusion, Warsaw (Poland)

    1996-08-01

    A dense jet of a plasma consisting of multiply charged ions was generated in the interaction of a laser plasma with a strong external axial magnetic field. It is shown that using the high-luminosity X-ray spectroheliograph technique allows to measure plasma emission spectra with 2-dimensional spatial resolution even in the cases when these spectra have small intensities. The X-ray spectroscopy and interferometry methods are used to measure plasma parameter distributions. The dependencies of N{sub e}(z) and T{sub e}(z) measured in this paper can be used to calculate the evolution of plasma ionization state during plasma expansion. The quasihomogeneous laser jet, which appears when a laser plasma interacts with an external magnetic field can be used not only to form an active medium of a short wavelength laser, but probably also to tackle the urgent problem of transport in a laser ion injector. (orig.).

  4. Simultaneous Observation of High Temperature Plasma of Solar Corona By TESIS CORONAS-PHOTON and XRT Hinode.

    Science.gov (United States)

    Reva, A.; Kuzin, S.; Bogachev, S.; Shestov, S.

    2012-05-01

    The Mg XII spectroheliograph is a part of instrumentation complex TESIS (satellite CORONAS-PHOTON). This instrument builds monochromatic images of hot plasma of the solar corona (λ = 8.42 Å, T>5 MK). The Mg XII spectroheliograph observed hot plasma in the non-flaring active-region NOAA 11019 during nine days. We reconstructed DEM of this active region with the help of genetic algorithm (we used data of the Mg XII spectroheliograph, XRT and EIT). Emission measure of the hot component amounts 1 % of the emission measure of the cool component.

  5. Self consistent MHD modeling of the solar wind from coronal holes with distinct geometries

    Science.gov (United States)

    Stewart, G. A.; Bravo, S.

    1995-01-01

    Utilizing an iterative scheme, a self-consistent axisymmetric MHD model for the solar wind has been developed. We use this model to evaluate the properties of the solar wind issuing from the open polar coronal hole regions of the Sun, during solar minimum. We explore the variation of solar wind parameters across the extent of the hole and we investigate how these variations are affected by the geometry of the hole and the strength of the field at the coronal base.

  6. Solar neutrino problem accounting for self-consistent magnetohydrodynamics solution for solar magnetic fields

    International Nuclear Information System (INIS)

    Miranda, O.G.; Pena-Garay, C.; Valle, J.W.F.; Rashba, T.I.; Semikoz, V.B.

    2001-01-01

    The analysis of the resonant spin-flavour (RSF) solutions to the solar neutrino problem in the framework of the simplest analytical solutions to the solar magnetohydrodynamics (MHD) equations is presented. We performed the global fit of the recent solar neutrino data, including event rates as well as zenith angle distributions and recoil electron spectra induced by solar neutrino interactions in Superkamiokande. We compare quantitatively our simplest MHD-RSF fit with vacuum oscillation (VAC) and MSW-type (SMA, LMA and LOW) solutions to the solar neutrino problem using a common well-calibrated theoretical calculation and fit procedure and find MHD-RSF fit to be somewhat better than those obtained for the favored neutrino oscillation solutions. We made the predictions for future experiments (e.g., SNO) to disentangle the MHD-RSF scenario from other scenarios

  7. A consistent thermodynamics of the MHD wave-heated two-fluid solar wind

    Directory of Open Access Journals (Sweden)

    I. V. Chashei

    Full Text Available We start our considerations from two more recent findings in heliospheric physics: One is the fact that the primary solar wind protons do not cool off adiabatically with distance, but appear to be heated. The other one is that secondary protons, embedded in the solar wind as pick-up ions, behave quasi-isothermal at their motion to the outer heliosphere. These two phenomena must be physically closely connected with each other. To demonstrate this we solve a coupled set of enthalpy flow conservation equations for the two-fluid solar wind system consisting of primary and secondary protons. The coupling of these equations comes by the heat sources that are relevant, namely the dissipation of MHD turbulence power to the respective protons at the relevant dissipation scales. Hereby we consider both the dissipation of convected turbulences and the dissipation of turbulences locally driven by the injection of new pick-up ions into an unstable mode of the ion distribution function. Conversion of free kinetic energy of freshly injected secondary ions into turbulence power is finally followed by partial reabsorption of this energy both by primary and secondary ions. We show solutions of simultaneous integrations of the coupled set of differential thermodynamic two-fluid equations and can draw interesting conclusions from the solutions obtained. We can show that the secondary proton temperature with increasing radial distance asymptotically attains a constant value with a magnitude essentially determined by the actual solar wind velocity. Furthermore, we study the primary proton temperature within this two-fluid context and find a polytropic behaviour with radially and latitudinally variable polytropic indices determined by the local heat sources due to dissipated turbulent wave energy. Considering latitudinally variable solar wind conditions, as published by McComas et al. (2000, we also predict latitudinal variations of primary proton temperatures at

  8. A consistent thermodynamics of the MHD wave-heated two-fluid solar wind

    Directory of Open Access Journals (Sweden)

    I. V. Chashei

    2003-07-01

    Full Text Available We start our considerations from two more recent findings in heliospheric physics: One is the fact that the primary solar wind protons do not cool off adiabatically with distance, but appear to be heated. The other one is that secondary protons, embedded in the solar wind as pick-up ions, behave quasi-isothermal at their motion to the outer heliosphere. These two phenomena must be physically closely connected with each other. To demonstrate this we solve a coupled set of enthalpy flow conservation equations for the two-fluid solar wind system consisting of primary and secondary protons. The coupling of these equations comes by the heat sources that are relevant, namely the dissipation of MHD turbulence power to the respective protons at the relevant dissipation scales. Hereby we consider both the dissipation of convected turbulences and the dissipation of turbulences locally driven by the injection of new pick-up ions into an unstable mode of the ion distribution function. Conversion of free kinetic energy of freshly injected secondary ions into turbulence power is finally followed by partial reabsorption of this energy both by primary and secondary ions. We show solutions of simultaneous integrations of the coupled set of differential thermodynamic two-fluid equations and can draw interesting conclusions from the solutions obtained. We can show that the secondary proton temperature with increasing radial distance asymptotically attains a constant value with a magnitude essentially determined by the actual solar wind velocity. Furthermore, we study the primary proton temperature within this two-fluid context and find a polytropic behaviour with radially and latitudinally variable polytropic indices determined by the local heat sources due to dissipated turbulent wave energy. Considering latitudinally variable solar wind conditions, as published by McComas et al. (2000, we also predict latitudinal variations of primary proton temperatures at

  9. Self consistent MHD modeling of the solar wind from polar coronal holes

    International Nuclear Information System (INIS)

    Stewart, G. A.; Bravo, S.

    1996-01-01

    We have developed a 2D self consistent MHD model for solar wind flow from antisymmetric magnetic geometries. We present results in the case of a photospheric magnetic field which has a dipolar configuration, in order to investigate some of the general characteristics of the wind at solar minimum. As in previous studies, we find that the magnetic configuration is that of a closed field region (a coronal helmet belt) around the solar equator, extending up to about 1.6 R · , and two large open field regions centred over the poles (polar coronal holes), whose magnetic and plasma fluxes expand to fill both hemispheres in interplanetary space. In addition, we find that the different geometries of the magnetic field lines across each hole (from the almost radial central polar lines to the highly curved border equatorial lines) cause the solar wind to have greatly different properties depending on which region it flows from. We find that, even though our simplified model cannot produce realistic wind values, we can obtain a polar wind that is faster, less dense and hotter than equatorial wind, and found that, close to the Sun, there exists a sharp transition between the two wind types. As these characteristics coincide with observations we conclude that both fast and slow solar wind can originate from coronal holes, fast wind from the centre, slow wind from the border

  10. A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood

    OpenAIRE

    Bell, Cameron P. M.; Mamajek, Eric E.; Naylor, Tim

    2015-01-01

    We present a self-consistent, absolute isochronal age scale for young (< 200 Myr), nearby (< 100 pc) moving groups in the solar neighbourhood based on homogeneous fitting of semi-empirical pre-main-sequence model isochrones using the tau^2 maximum-likelihood fitting statistic of Naylor & Jeffries in the M_V, V-J colour-magnitude diagram. The final adopted ages for the groups are: 149+51-19 Myr for the AB Dor moving group, 24+/-3 Myr for the {\\beta} Pic moving group (BPMG), 45+11-7 Myr for the...

  11. Providing Consistent (A)ATSR Solar Channel Radiometry for Climate Studies

    Science.gov (United States)

    Smith, D.; Latter, B. G.; Poulsen, C.

    2012-04-01

    Data from the solar reflectance channels of the Along Track Scanning Radiometer (ATSR) series of instruments are being used in applications for monitoring trends in clouds and aerosols. In order to provide quantitative information, the radiometric calibrations of the sensors must be consistent, stable and ideally traced to international standards. This paper describes the methods used to monitor the calibrations of the ATSR instruments to provide consistent Level 1b radiometric data sets. Comparisons of the in-orbit calibrations are made by reference to data from quasi stable sites such as DOME-C in Antarctica or Saharan Desert sites. Comparisons are performed either by time coincident match-ups of the radiometric data for sensors having similar spectral bands and view/solar geometry and overpass times as for AATSR and MERIS; or via a reference BRDF model derived from averages of measurements over the site from a reference sensor where there is limited or no temporal overlap (e.g. MODIS-Aqua, ATSR-1 and ATSR-2). The results of the intercomparisons provide values of the long term calibration drift and systematic biases between the sensors. Look-up tables based on smoothed averages of the drift measurements are used to provide the corrections to Level 1b data. The uncertainty budgets for the comparisons are provided. It is also possible to perform comparisons of measurements against high spectral resolution instruments that are co-located on the same platform, i.e. AATSR/SCIA on ENVISAT and ATSR-2/GOME on ERS-2. The comparisons are performed by averaging the spectrometer data to the spectral response of the filter radiometer, and averaging the radiometer data to the spatial resolution of the spectrometer. In this paper, the authors present the results of the inter-comparisons to achieve a consistent calibration for the solar channels of the complete ATSR dataset. An assessment of the uncertainties associated with the techniques will be discussed. The impacts of the

  12. Consistency of seven different GNSS global ionospheric mapping techniques during one solar cycle

    Science.gov (United States)

    Roma-Dollase, David; Hernández-Pajares, Manuel; Krankowski, Andrzej; Kotulak, Kacper; Ghoddousi-Fard, Reza; Yuan, Yunbin; Li, Zishen; Zhang, Hongping; Shi, Chuang; Wang, Cheng; Feltens, Joachim; Vergados, Panagiotis; Komjathy, Attila; Schaer, Stefan; García-Rigo, Alberto; Gómez-Cama, José M.

    2018-06-01

    In the context of the International GNSS Service (IGS), several IGS Ionosphere Associated Analysis Centers have developed different techniques to provide global ionospheric maps (GIMs) of vertical total electron content (VTEC) since 1998. In this paper we present a comparison of the performances of all the GIMs created in the frame of IGS. Indeed we compare the classical ones (for the ionospheric analysis centers CODE, ESA/ESOC, JPL and UPC) with the new ones (NRCAN, CAS, WHU). To assess the quality of them in fair and completely independent ways, two assessment methods are used: a direct comparison to altimeter data (VTEC-altimeter) and to the difference of slant total electron content (STEC) observed in independent ground reference stations (dSTEC-GPS). The main conclusion of this study, performed during one solar cycle, is the consistency of the results between so many different GIM techniques and implementations.

  13. A self-consistent, absolute isochronal age scale for young moving groups in the solar neighbourhood

    Science.gov (United States)

    Bell, Cameron P. M.; Mamajek, Eric E.; Naylor, Tim

    2015-11-01

    We present a self-consistent, absolute isochronal age scale for young ( ≲ 200 Myr), nearby ( ≲ 100 pc) moving groups in the solar neighbourhood based on homogeneous fitting of semi-empirical pre-main-sequence model isochrones using the τ2 maximum-likelihood fitting statistic of Naylor & Jeffries in the MV, V - J colour-magnitude diagram. The final adopted ages for the groups are as follows: 149^{+51}_{-19} {Myr} for the AB Dor moving group, 24 ± 3 Myr for the β Pic moving group (BPMG), 45^{+11}_{-7} {Myr} for the Carina association, 42^{+6}_{-4} {Myr} for the Columba association, 11 ± 3 Myr for the η Cha cluster, 45 ± 4 Myr for the Tucana-Horologium moving group (Tuc-Hor), 10 ± 3 Myr for the TW Hya association and 22^{+4}_{-3} {Myr} for the 32 Ori group. At this stage we are uncomfortable assigning a final, unambiguous age to the Argus association as our membership list for the association appears to suffer from a high level of contamination, and therefore it remains unclear whether these stars represent a single population of coeval stars. Our isochronal ages for both the BPMG and Tuc-Hor are consistent with recent lithium depletion boundary (LDB) ages, which unlike isochronal ages, are relatively insensitive to the choice of low-mass evolutionary models. This consistency between the isochronal and LDB ages instils confidence that our self-consistent, absolute age scale for young, nearby moving groups is robust, and hence we suggest that these ages be adopted for future studies of these groups. Software implementing the methods described in this study is available from http://www.astro.ex.ac.uk/people/timn/tau-squared/.

  14. Simulation of a solar collector array consisting of two types of solar collectors, with and without convection barrier

    DEFF Research Database (Denmark)

    Bava, Federico; Furbo, Simon; Perers, Bengt

    2015-01-01

    The installed area of solar collectors in solar heating fields is rapidly increasing in Denmark. In this scenario even relatively small performance improvements may lead to a large increase in the overall energy production. Both collectors with and without polymer foil, functioning as convection...... barrier, can be found on the Danish market. Depending on the temperature level at which the two types of collectors operate, one can perform better than the other. This project aimed to study the behavior of a 14 solar collector row made of these two different kinds of collectors, in order to optimize...... the composition of the row. Actual solar collectors available on the Danish market (models HT-SA and HT-A 35-10 manufactured by ARCON Solar A/S) were used for this analysis. To perform the study, a simulation model in TRNSYS was developed based on the Danish solar collector field in Braedstrup. A parametric...

  15. A miniature solar device for overall water splitting consisting of series-connected spherical silicon solar cells

    KAUST Repository

    Kageshima, Yosuke

    2016-04-18

    A novel “photovoltaics (PV) + electrolyzer” concept is presented using a simple, small, and completely stand-alone non-biased device for solar-driven overall water splitting. Three or four spherical-shaped p-n junction silicon balls were successfully connected in series, named “SPHELAR.” SPHELAR possessed small projected areas of 0.20 (3PVs) and 0.26 cm2 (4PVs) and exhibited working voltages sufficient for water electrolysis. Impacts of the configuration on the PV module performance were carefully analyzed, revealing that a drastic increase in the photocurrent (≈20%) was attained by the effective utilization of a reflective sheet. Separate investigations on the electrocatalyst performance showed that non-noble metal based materials with reasonably small sizes (<0.80 cm2) exhibited substantial currents at the PV working voltage. By combining the observations of the PV characteristics, light management and electrocatalyst performance, solar-driven overall water splitting was readily achieved, reaching solar-to-hydrogen efficiencies of 7.4% (3PVs) and 6.4% (4PVs).

  16. A miniature solar device for overall water splitting consisting of series-connected spherical silicon solar cells

    KAUST Repository

    Kageshima, Yosuke; Shinagawa, Tatsuya; Kuwata, Takaaki; Nakata, Josuke; Minegishi, Tsutomu; Takanabe, Kazuhiro; Domen, Kazunari

    2016-01-01

    A novel “photovoltaics (PV) + electrolyzer” concept is presented using a simple, small, and completely stand-alone non-biased device for solar-driven overall water splitting. Three or four spherical-shaped p-n junction silicon balls were successfully connected in series, named “SPHELAR.” SPHELAR possessed small projected areas of 0.20 (3PVs) and 0.26 cm2 (4PVs) and exhibited working voltages sufficient for water electrolysis. Impacts of the configuration on the PV module performance were carefully analyzed, revealing that a drastic increase in the photocurrent (≈20%) was attained by the effective utilization of a reflective sheet. Separate investigations on the electrocatalyst performance showed that non-noble metal based materials with reasonably small sizes (<0.80 cm2) exhibited substantial currents at the PV working voltage. By combining the observations of the PV characteristics, light management and electrocatalyst performance, solar-driven overall water splitting was readily achieved, reaching solar-to-hydrogen efficiencies of 7.4% (3PVs) and 6.4% (4PVs).

  17. Cosmological evolution and Solar System consistency of massive scalar-tensor gravity

    Science.gov (United States)

    de Pirey Saint Alby, Thibaut Arnoulx; Yunes, Nicolás

    2017-09-01

    The scalar-tensor theory of Damour and Esposito-Farèse recently gained some renewed interest because of its ability to suppress modifications to general relativity in the weak field, while introducing large corrections in the strong field of compact objects through a process called scalarization. A large sector of this theory that allows for scalarization, however, has been shown to be in conflict with Solar System observations when accounting for the cosmological evolution of the scalar field. We here study an extension of this theory by endowing the scalar field with a mass to determine whether this allows the theory to pass Solar System constraints upon cosmological evolution for a larger sector of coupling parameter space. We show that the cosmological scalar field goes first through a quiescent phase, similar to the behavior of a massless field, but then it enters an oscillatory phase, with an amplitude (and frequency) that decays (and grows) exponentially. We further show that after the field enters the oscillatory phase, its effective energy density and pressure are approximately those of dust, as expected from previous cosmological studies. Due to these oscillations, we show that the scalar field cannot be treated as static today on astrophysical scales, and so we use time-dependent perturbation theory to compute the scalar-field-induced modifications to Solar System observables. We find that these modifications are suppressed when the mass of the scalar field and the coupling parameter of the theory are in a wide range, allowing the theory to pass Solar System constraints, while in principle possibly still allowing for scalarization.

  18. Thermal analysis of a solar collector consisting of V cavities for water heating; Analise termica de um coletor solar composto de cavidades V para aquecimento de agua

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Michel Fabio de Souza

    2009-03-15

    The solar water heating is carried through, in Brazil, by means of solar heaters compound for collectors flat plate of the type plate-and-pipes, devices that operate in stationary position and they do not require tracking of the sun. A compound collector for some formed V-trough concentrators can be an alternative to the conventional solar collectors flat plate. This compound collector for V-trough is considered, each one, for side-walls which are specularly reflecting surfaces associates in V (equivalent to a triangular gutter). Next to the vertex to each V-trough concentrators an absorber tube is fixed, for flow of the fluid to be heated. Interconnection of the absorbers tubes forms a similar tubular network existing in solar collectors of the type the plate and pipe. V-trough concentrators with the absorbers tubes are made use in series in the interior a prismatic box, which have one of its faces consisting by a glass covering and directed toward incidence of the solar radiation. An analysis of thermal performance of these devices operating stationary and without tracking of the sun is researched. A mathematical model for the computational simulation of the optical and thermal performance of these concentrative devices is elaborated, whose implementation was carried through software EES (Engineering Equation Solver). The efficiency optics of V-trough concentrators with cylindrical absorbers is calculated from the adaptation of the methodology used for Fraidenraich (1994), proposal for Hollands (1971) for V-trough cavities with plain absorbers. The thermal analysis of the considered collector was based on the applied methodology the CPC for Hsieh (1981) and Leao (1989). Relative results to the thermal performance of V-trough concentrators suggest that these configurations are not competitive, technique and economically, with the conventional plain collectors. Although some geometric configurations presented next thermal efficiencies to the conventional plain

  19. Hybrid Dye-Sensitized Solar Cells Consisting of Double Titania Layers for Harvesting Light with Wide Range of Wavelengths

    Science.gov (United States)

    Sadamasu, Kengo; Inoue, Takafumi; Ogomi, Yuhei; Pandey, Shyam S.; Hayase, Shuzi

    2011-02-01

    We report a hybrid dye-sensitized solar cell consisting of double titania layers (top and bottom layers) stained with two dyes. A top layer fabricated on a glass was mechanically pressed with a bottom layer fabricated on a glass cloth. The glass cloth acts as a supporter of a porous titania layer as well as a holder of electrolyte. The incident photon to current efficiency (IPCE) curve had two peaks corresponding to those of the two dyes, which demonstrates that electrons are collected from both the top and bottom layers.

  20. Solar X-ray bursts

    International Nuclear Information System (INIS)

    Urnov, A.M.

    1980-01-01

    In the popular form the consideration is given to the modern state tasks and results of X-ray spectrometry of solar bursts. The operation of X-ray spectroheliograph is described. Results of spectral and polarization measurings of X-ray radiation of one powerful solar burst are presented. The conclusion has been drawn that in the process of burst development three characteristic stages may be distingwished: 1) the initial phase; just in this period processes which lead to observed consequences-electromagnetic and corpuscular radiation are born; 2) the impulse phase, or the phase of maximum, is characterised by sharp increase of radiation flux. During this phase the main energy content emanates and some volumes of plasma warm up to high temperatures; 3) the phase of burst damping, during which plasma cools and reverts to the initial condition

  1. Photometric measurements of solar irradiance variations due to sunspots

    International Nuclear Information System (INIS)

    Chapman, G.A.; Herzog, A.D.; Laico, D.E.; Lawrence, J.K.; Templer, M.S.

    1989-01-01

    A photometric telescope constructed to obtain photometric sunspot areas and deficits on a daily basis is described. Data from this Cartesian full disk telescope (CFDT) are analyzed with attention given to the period between June 4 and June 17, 1985 because of the availability of overlapping sunspot area and irradiance deficit data from high-resolution digital spectroheliograms made with the San Fernando Observatory 28 cm vacuum solar telescope and spectroheliograph. The CFDT sunspot deficits suggest a substantial irradiance contribution from faculae and active region plage. 23 refs

  2. Gravitation Theory: Empirical Status from Solar System Experiments: All observations to date are consistent with Einstein's general relativity theory of gravity.

    Science.gov (United States)

    Nordtvedt, K L

    1972-12-15

    I have reviewed the historical and contemporary experiments that guide us in choosing a post-Newtonian, relativistic gravitational theory. The foundation experiments essentially constrain gravitation theory to be a metric theory in which matter couples solely to one gravitational field, the metric field, although other cosmological gravitational fields may exist. The metric field for any metric theory can be specified (for the solar system, for our present purposes) by a series of potential terms with several parameters. A variety of experiments specify (or put limits on) the numerical values of the seven parameters in the post-Newtonian metric field, and other such experiments have been planned. The empirical results, to date, yield values of the parameters that are consistent with the predictions of Einstein's general relativity.

  3. Spatial-temporal consistency between gross primary productivity and solar-induced chlorophyll fluorescence of vegetation in China during 2007-2014.

    Science.gov (United States)

    Ma, Jun; Xiao, Xiangming; Zhang, Yao; Doughty, Russell; Chen, Bangqian; Zhao, Bin

    2018-10-15

    Accurately estimating spatial-temporal patterns of gross primary production (GPP) is important for the global carbon cycle. Satellite-based light use efficiency (LUE) models are regarded as an efficient tool in simulating spatial-temporal dynamics of GPP. However, the accuracy assessment of GPP simulations from LUE models at both spatial and temporal scales remains a challenge. In this study, we simulated GPP of vegetation in China during 2007-2014 using a LUE model (Vegetation Photosynthesis Model, VPM) based on MODIS (moderate-resolution imaging spectroradiometer) images with 8-day temporal and 500-m spatial resolutions and NCEP (National Center for Environmental Prediction) climate data. Global Ozone Monitoring Instrument 2 (GOME-2) solar-induced chlorophyll fluorescence (SIF) data were used to compare with VPM simulated GPP (GPP VPM ) temporally and spatially using linear correlation analysis. Significant positive linear correlations exist between monthly GPP VPM and SIF data over a single year (2010) and multiple years (2007-2014) in most areas of China. GPP VPM is also significantly positive correlated with GOME-2 SIF (R 2  > 0.43) spatially for seasonal scales. However, poor consistency was detected between GPP VPM and SIF data at yearly scale. GPP dynamic trends have high spatial-temporal variation in China during 2007-2014. Temperature, leaf area index (LAI), and precipitation are the most important factors influence GPP VPM in the regions of East Qinghai-Tibet Plateau, Loss Plateau, and Southwestern China, respectively. The results of this study indicate that GPP VPM is temporally and spatially in line with GOME-2 SIF data, and space-borne SIF data have great potential for evaluating LUE-based GPP models. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Interface Consistency

    DEFF Research Database (Denmark)

    Staunstrup, Jørgen

    1998-01-01

    This paper proposes that Interface Consistency is an important issue for the development of modular designs. Byproviding a precise specification of component interfaces it becomes possible to check that separately developedcomponents use a common interface in a coherent matter thus avoiding a very...... significant source of design errors. Awide range of interface specifications are possible, the simplest form is a syntactical check of parameter types.However, today it is possible to do more sophisticated forms involving semantic checks....

  5. Spatial-temporal consistency between gross primary productivity and solar-induced chlorophyll fluorescence of vegetation in China during 2007-2014

    Science.gov (United States)

    Ma, J.; Xiao, X.; Zhang, Y.; Chen, B.; Zhao, B.

    2017-12-01

    Great significance exists in accurately estimating spatial-temporal patterns of gross primary production (GPP) because of its important role in global carbon cycle. Satellite-based light use efficiency (LUE) models are regarded as an efficient tool in simulating spatially time-sires GPP. However, the estimation of the accuracy of GPP simulations from LUE at both spatial and temporal scales is still a challenging work. In this study, we simulated GPP of vegetation in China during 2007-2014 using a LUE model (Vegetation Photosynthesis Model, VPM) based on MODIS (moderate-resolution imaging spectroradiometer) images of 8-day temporal and 500-m spatial resolutions and NCEP (National Center for Environmental Prediction) climate data. Global Ozone Monitoring Instrument 2 (GOME-2) solar-induced chlorophyll fluorescence (SIF) data were used to compare with VPM simulated GPP (GPPVPM) temporally and spatially using linear correlation analysis. Significant positive linear correlations exist between monthly GPPVPM and SIF data over both single year (2010) and multiple years (2007-2014) in China. Annual GPPVPM is significantly positive correlated with SIF (R2>0.43) spatially for all years during 2007-2014 and all seasons in 2010 (R2>0.37). GPP dynamic trends is high spatial-temporal heterogeneous in China during 2007-2014. The results of this study indicate that GPPVPM is temporally and spatially in line with SIF data, and space-borne SIF data have great potential in validating and parameterizing GPP estimation of LUE-based models.

  6. Enhanced Efficiency of Dye-Sensitized Solar Counter Electrodes Consisting of Two-Dimensional Nanostructural Molybdenum Disulfide Nanosheets Supported Pt Nanoparticles

    Directory of Open Access Journals (Sweden)

    Chao-Kuang Cheng

    2017-10-01

    Full Text Available This paper reports architecturally designed nanocomposites synthesized by hybridizing the two-dimensional (2D nanostructure of molybdenum disulfide (MoS2 nanosheet (NS-supported Pt nanoparticles (PtNPs as counter electrodes (CEs for dye-sensitized solar cells (DSSCs. MoS2 NSs were prepared using the hydrothermal method; PtNPs were subsequently reduced on the MoS2 NSs via the water–ethylene method to form PtNPs/MoS2 NSs hybrids. The nanostructures and chemical states of the PtNPs/MoS2 NSs hybrids were characterized by high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. Detailed electrochemical characterizations by electrochemical impedance spectroscopy, cyclic voltammetry, and Tafel-polarization measurement demonstrated that the PtNPs/MoS2 NSs exhibited excellent electrocatalytic activities, afforded a higher charge transfer rate, a decreased charge transfer resistance, and an improved exchange current density. The PtNPs/MoS2 NSs hybrids not only provided the exposed layers of 2D MoS2 NSs with a great deal of catalytically active sites, but also offered PtNPs anchored on the MoS2 NSs enhanced I3− reduction. Accordingly, the DSSCs that incorporated PtNPs/MoS2 NSs CE exhibited an outstanding photovoltaic conversion efficiency (PCE of 7.52%, which was 8.7% higher than that of a device with conventional thermally-deposited platinum CE (PCE = 6.92%.

  7. An alternative to the plasma emission model: Particle-in-cell, self-consistent electromagnetic wave emission simulations of solar type III radio bursts

    International Nuclear Information System (INIS)

    Tsiklauri, David

    2011-01-01

    High-resolution (sub-Debye length grid size and 10 000 particle species per cell), 1.5D particle-in-cell, relativistic, fully electromagnetic simulations are used to model electromagnetic wave emission generation in the context of solar type III radio bursts. The model studies generation of electromagnetic waves by a super-thermal, hot beam of electrons injected into a plasma thread that contains uniform longitudinal magnetic field and a parabolic density gradient. In effect, a single magnetic line connecting Sun to Earth is considered, for which five cases are studied. (i) We find that the physical system without a beam is stable and only low amplitude level electromagnetic drift waves (noise) are excited. (ii) The beam injection direction is controlled by setting either longitudinal or oblique electron initial drift speed, i.e., by setting the beam pitch angle (the angle between the beam velocity vector and the direction of background magnetic field). In the case of zero pitch angle, i.e., when v-vector b ·E-vector perpendicular =0, the beam excites only electrostatic, standing waves, oscillating at local plasma frequency, in the beam injection spatial location, and only low level electromagnetic drift wave noise is also generated. (iii) In the case of oblique beam pitch angles, i.e., when v-vector b ·E-vector perpendicular =0, again electrostatic waves with same properties are excited. However, now the beam also generates the electromagnetic waves with the properties commensurate to type III radio bursts. The latter is evidenced by the wavelet analysis of transverse electric field component, which shows that as the beam moves to the regions of lower density and hence lower plasma frequency, frequency of the electromagnetic waves drops accordingly. (iv) When the density gradient is removed, an electron beam with an oblique pitch angle still generates the electromagnetic radiation. However, in the latter case no frequency decrease is seen. (v) Since in most of

  8. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    OpenAIRE

    M. Norhafana; Ahmad Faris Ismail; Z. A. A. Majid

    2015-01-01

    Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of...

  9. Structural Consistency, Consistency, and Sequential Rationality.

    OpenAIRE

    Kreps, David M; Ramey, Garey

    1987-01-01

    Sequential equilibria comprise consistent beliefs and a sequentially ra tional strategy profile. Consistent beliefs are limits of Bayes ratio nal beliefs for sequences of strategies that approach the equilibrium strategy. Beliefs are structurally consistent if they are rationaliz ed by some single conjecture concerning opponents' strategies. Consis tent beliefs are not necessarily structurally consistent, notwithstan ding a claim by Kreps and Robert Wilson (1982). Moreover, the spirit of stru...

  10. Consistent model driven architecture

    Science.gov (United States)

    Niepostyn, Stanisław J.

    2015-09-01

    The goal of the MDA is to produce software systems from abstract models in a way where human interaction is restricted to a minimum. These abstract models are based on the UML language. However, the semantics of UML models is defined in a natural language. Subsequently the verification of consistency of these diagrams is needed in order to identify errors in requirements at the early stage of the development process. The verification of consistency is difficult due to a semi-formal nature of UML diagrams. We propose automatic verification of consistency of the series of UML diagrams originating from abstract models implemented with our consistency rules. This Consistent Model Driven Architecture approach enables us to generate automatically complete workflow applications from consistent and complete models developed from abstract models (e.g. Business Context Diagram). Therefore, our method can be used to check practicability (feasibility) of software architecture models.

  11. Bitcoin Meets Strong Consistency

    OpenAIRE

    Decker, Christian; Seidel, Jochen; Wattenhofer, Roger

    2014-01-01

    The Bitcoin system only provides eventual consistency. For everyday life, the time to confirm a Bitcoin transaction is prohibitively slow. In this paper we propose a new system, built on the Bitcoin blockchain, which enables strong consistency. Our system, PeerCensus, acts as a certification authority, manages peer identities in a peer-to-peer network, and ultimately enhances Bitcoin and similar systems with strong consistency. Our extensive analysis shows that PeerCensus is in a secure state...

  12. Consistent classical supergravity theories

    International Nuclear Information System (INIS)

    Muller, M.

    1989-01-01

    This book offers a presentation of both conformal and Poincare supergravity. The consistent four-dimensional supergravity theories are classified. The formulae needed for further modelling are included

  13. Hierarchical structures consisting of SiO2 nanorods and p-GaN microdomes for efficiently harvesting solar energy for InGaN quantum well photovoltaic cells.

    Science.gov (United States)

    Ho, Cheng-Han; Lien, Der-Hsien; Chang, Hung-Chih; Lin, Chin-An; Kang, Chen-Fang; Hsing, Meng-Kai; Lai, Kun-Yu; He, Jr-Hau

    2012-12-07

    We experimentally and theoretically demonstrated the hierarchical structure of SiO(2) nanorod arrays/p-GaN microdomes as a light harvesting scheme for InGaN-based multiple quantum well solar cells. The combination of nano- and micro-structures leads to increased internal multiple reflection and provides an intermediate refractive index between air and GaN. Cells with the hierarchical structure exhibit improved short-circuit current densities and fill factors, rendering a 1.47 fold efficiency enhancement as compared to planar cells.

  14. Consistency of orthodox gravity

    Energy Technology Data Exchange (ETDEWEB)

    Bellucci, S. [INFN, Frascati (Italy). Laboratori Nazionali di Frascati; Shiekh, A. [International Centre for Theoretical Physics, Trieste (Italy)

    1997-01-01

    A recent proposal for quantizing gravity is investigated for self consistency. The existence of a fixed-point all-order solution is found, corresponding to a consistent quantum gravity. A criterion to unify couplings is suggested, by invoking an application of their argument to more complex systems.

  15. Quasiparticles and thermodynamical consistency

    International Nuclear Information System (INIS)

    Shanenko, A.A.; Biro, T.S.; Toneev, V.D.

    2003-01-01

    A brief and simple introduction into the problem of the thermodynamical consistency is given. The thermodynamical consistency relations, which should be taken into account under constructing a quasiparticle model, are found in a general manner from the finite-temperature extension of the Hellmann-Feynman theorem. Restrictions following from these relations are illustrated by simple physical examples. (author)

  16. Relationship of magnetic field strength and brightness of fine-structure elements in the solar temperature minimum region

    Science.gov (United States)

    Cook, J. W.; Ewing, J. A.

    1990-01-01

    A quantitative relationship was determined between magnetic field strength (or magnetic flux) from photospheric magnetograph observations and the brightness temperature of solar fine-structure elements observed at 1600 A, where the predominant flux source is continuum emission from the solar temperature minimum region. A Kitt Peak magnetogram and spectroheliograph observations at 1600 A taken during a sounding rocket flight of the High Resolution Telescope and Spectrograph from December 11, 1987 were used. The statistical distributions of brightness temperature in the quiet sun at 1600 A, and absolute value of magnetic field strength in the same area were determined from these observations. Using a technique which obtains the best-fit relationship of a given functional form between these two histogram distributions, a quantitative relationship was determined between absolute value of magnetic field strength B and brightness temperature which is essentially linear from 10 to 150 G. An interpretation is suggested, in which a basal heating occurs generally, while brighter elements are produced in magnetic regions with temperature enhancements proportional to B.

  17. Consistency in PERT problems

    OpenAIRE

    Bergantiños, Gustavo; Valencia-Toledo, Alfredo; Vidal-Puga, Juan

    2016-01-01

    The program evaluation review technique (PERT) is a tool used to schedule and coordinate activities in a complex project. In assigning the cost of a potential delay, we characterize the Shapley rule as the only rule that satisfies consistency and other desirable properties.

  18. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    Directory of Open Access Journals (Sweden)

    M. Norhafana

    2015-11-01

    Full Text Available Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of a solar water heating system as well as to evaluate the performance of the solar collector in terms of useful heat of the multilayered absorber using the multidirectional ability of a solar simulator at several values of solar radiation. It is operated at three variables of solar radiation of 400 W/m2, 550 W/m2 and 700 W/m2 and using three different positions of angles at 0º, 45º and 90º. The results show that the multilayer absorber in the solar collector is only able to best adapt at 45° of solar simulator with different values of radiation intensity. At this angle the maximum values of useful heat and temperature difference are achieved. KEYWORDS: solar water heating system; solar collector; multilayered absorber; solar simulator; solar radiation 

  19. Reporting consistently on CSR

    DEFF Research Database (Denmark)

    Thomsen, Christa; Nielsen, Anne Ellerup

    2006-01-01

    This chapter first outlines theory and literature on CSR and Stakeholder Relations focusing on the different perspectives and the contextual and dynamic character of the CSR concept. CSR reporting challenges are discussed and a model of analysis is proposed. Next, our paper presents the results...... of a case study showing that companies use different and not necessarily consistent strategies for reporting on CSR. Finally, the implications for managerial practice are discussed. The chapter concludes by highlighting the value and awareness of the discourse and the discourse types adopted...... in the reporting material. By implementing consistent discourse strategies that interact according to a well-defined pattern or order, it is possible to communicate a strong social commitment on the one hand, and to take into consideration the expectations of the shareholders and the other stakeholders...

  20. Four-cell solar tracker

    Science.gov (United States)

    Berdahl, C. M.

    1981-01-01

    Forty cm Sun tracker, consisting of optical telescope and four solar cells, stays pointed at Sun throughout day for maximum energy collection. Each solar cell generates voltage proportional to part of solar image it receives; voltages drive servomotors that keep image centered. Mirrored portion of cylinder extends acquisition angle of device by reflecting Sun image back onto solar cells.

  1. Pyramid solar micro-grid

    Science.gov (United States)

    Huang, Bin-Juine; Hsu, Po-Chien; Wang, Yi-Hung; Tang, Tzu-Chiao; Wang, Jia-Wei; Dong, Xin-Hong; Hsu, Hsin-Yi; Li, Kang; Lee, Kung-Yen

    2018-03-01

    A novel pyramid solar micro-grid is proposed in the present study. All the members within the micro-grid can mutually share excess solar PV power each other through a binary-connection hierarchy. The test results of a 2+2 pyramid solar micro-grid consisting of 4 individual solar PV systems for self-consumption are reported.

  2. Geometrically Consistent Mesh Modification

    KAUST Repository

    Bonito, A.

    2010-01-01

    A new paradigm of adaptivity is to execute refinement, coarsening, and smoothing of meshes on manifolds with incomplete information about their geometry and yet preserve position and curvature accuracy. We refer to this collectively as geometrically consistent (GC) mesh modification. We discuss the concept of discrete GC, show the failure of naive approaches, and propose and analyze a simple algorithm that is GC and accuracy preserving. © 2010 Society for Industrial and Applied Mathematics.

  3. Solar cells

    International Nuclear Information System (INIS)

    1980-01-01

    A method of producing solar cells is described which consists of producing a substantially monocrystalline tubular body of silicon or other suitable semiconductor material, treating this body to form an annular rectifying junction and then cutting it longitudinally to form a number of nearly flat ribbons from which the solar cells are fabricated. The P=N rectifying junction produced by the formation of silicon dioxide on the layers at the inner and outer surfaces of the body can be formed by ion-implantation or diffusion. (U.K.)

  4. The Rucio Consistency Service

    CERN Document Server

    Serfon, Cedric; The ATLAS collaboration

    2016-01-01

    One of the biggest challenge with Large scale data management system is to ensure the consistency between the global file catalog and what is physically on all storage elements. To tackle this issue, the Rucio software which is used by the ATLAS Distributed Data Management system has been extended to automatically handle lost or unregistered files (aka Dark Data). This system automatically detects these inconsistencies and take actions like recovery or deletion of unneeded files in a central manner. In this talk, we will present this system, explain the internals and give some results.

  5. Is cosmology consistent?

    International Nuclear Information System (INIS)

    Wang Xiaomin; Tegmark, Max; Zaldarriaga, Matias

    2002-01-01

    We perform a detailed analysis of the latest cosmic microwave background (CMB) measurements (including BOOMERaNG, DASI, Maxima and CBI), both alone and jointly with other cosmological data sets involving, e.g., galaxy clustering and the Lyman Alpha Forest. We first address the question of whether the CMB data are internally consistent once calibration and beam uncertainties are taken into account, performing a series of statistical tests. With a few minor caveats, our answer is yes, and we compress all data into a single set of 24 bandpowers with associated covariance matrix and window functions. We then compute joint constraints on the 11 parameters of the 'standard' adiabatic inflationary cosmological model. Our best fit model passes a series of physical consistency checks and agrees with essentially all currently available cosmological data. In addition to sharp constraints on the cosmic matter budget in good agreement with those of the BOOMERaNG, DASI and Maxima teams, we obtain a heaviest neutrino mass range 0.04-4.2 eV and the sharpest constraints to date on gravity waves which (together with preference for a slight red-tilt) favor 'small-field' inflation models

  6. Consistent Quantum Theory

    Science.gov (United States)

    Griffiths, Robert B.

    2001-11-01

    Quantum mechanics is one of the most fundamental yet difficult subjects in physics. Nonrelativistic quantum theory is presented here in a clear and systematic fashion, integrating Born's probabilistic interpretation with Schrödinger dynamics. Basic quantum principles are illustrated with simple examples requiring no mathematics beyond linear algebra and elementary probability theory. The quantum measurement process is consistently analyzed using fundamental quantum principles without referring to measurement. These same principles are used to resolve several of the paradoxes that have long perplexed physicists, including the double slit and Schrödinger's cat. The consistent histories formalism used here was first introduced by the author, and extended by M. Gell-Mann, J. Hartle and R. Omnès. Essential for researchers yet accessible to advanced undergraduate students in physics, chemistry, mathematics, and computer science, this book is supplementary to standard textbooks. It will also be of interest to physicists and philosophers working on the foundations of quantum mechanics. Comprehensive account Written by one of the main figures in the field Paperback edition of successful work on philosophy of quantum mechanics

  7. Solarization soil

    International Nuclear Information System (INIS)

    Abou Ghraibe, W.

    1995-01-01

    Solar energy could be used in pest control, in soil sterilization technology. The technique consists of covering humid soils by plastic films steadily fixed to the soil. Timing must be in summer during 4-8 weeks, where soil temperature increases to degrees high enough to control pests or to produce biological and chemical changes. The technique could be applied on many pests soil, mainly fungi, bacteria, nematods, weeds and pest insects. The technique could be used in greenhouses as well as in plastic film covers or in orchards where plastic films present double benefits: soil sterilization and production of black mulch. Mechanism of soil solarization is explained. Results show that soil solarization can be used in pest control after fruit crops cultivation and could be a method for an integrated pest control. 9 refs

  8. Solar Indices - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  9. Solar Indices - Solar Ultraviolet

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  10. Solar Indices - Solar Corona

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  11. Solar Indices - Solar Irradiance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  12. Solar building

    OpenAIRE

    Zhang, Luxin

    2014-01-01

    In my thesis I describe the utilization of solar energy and solar energy with building integration. In introduction it is also mentioned how the solar building works, trying to make more people understand and accept the solar building. The thesis introduces different types of solar heat collectors. I compared the difference two operation modes of solar water heating system and created examples of solar water system selection. I also introduced other solar building applications. It is conv...

  13. Solar energy

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This chapter discusses the role solar energy may have in the energy future of the US. The topics discussed in the chapter include the solar resource, solar architecture including passive solar design and solar collectors, solar-thermal concentrating systems including parabolic troughs and dishes and central receivers, photovoltaic cells including photovoltaic systems for home use, and environmental, health and safety issues

  14. Solar Technology Curriculum, 1980.

    Science.gov (United States)

    Seward County Community Coll., Liberal, KS.

    This curriculum guide contains lecture outlines and handouts for training solar technicians in the installation, maintenance, and repair of solar energy hot water and space heating systems. The curriculum consists of four modular units developed to provide a model through which community colleges and area vocational/technical schools can respond…

  15. Solar Water Heater Installation Package

    Science.gov (United States)

    1982-01-01

    A 48-page report describes water-heating system, installation (covering collector orientation, mounting, plumbing and wiring), operating instructions and maintenance procedures. Commercial solar-powered water heater system consists of a solar collector, solar-heated-water tank, electrically heated water tank and controls. Analysis of possible hazards from pressure, electricity, toxicity, flammability, gas, hot water and steam are also included.

  16. A CONCEPT OF SOLAR TRACKER SYSTEM DESIGN

    OpenAIRE

    Meita Rumbayan *, Muhamad Dwisnanto Putro

    2017-01-01

    Improvement of solar panel efficiency is an ongoing research work recently. Maximizing the output power by integrating with the solar tracker system becomes a interest point of the research. This paper presents the concept in designing a solar tracker system applied to solar panel. The development of solar panel tracker system design that consist of system display prototype design, hardware design, and algorithm design. This concept is useful as the control system for solar tracker to improve...

  17. Solar Features - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A solar flare is a short-lived sudden increase in the intensity of radiation emitted in the neighborhood of sunspots. For many years it was best monitored in the...

  18. Solar storms; Tormentas solares

    Energy Technology Data Exchange (ETDEWEB)

    Collaboration: Pereira Cuesta, S.; Pereira Pagan, B.

    2016-08-01

    Solar storms begin with an explosion, or solar flare, on the surface of the sun. The X-rays and extreme ultraviolet radiation from the flare reach the Earths orbit minutes later-travelling at light speed. The ionization of upper layers of our atmosphere could cause radio blackouts and satellite navigation errors (GPS). Soon after, a wave of energetic particles, electrons and protons accelerated by the explosion crosses the orbit of the Earth, and can cause real and significant damage. (Author)

  19. Solar irridiance variations and solar activity

    International Nuclear Information System (INIS)

    Willson, R.C.

    1982-01-01

    A mean value for the 1 AU total solar irradiance of 1368.2 W/m 2 and a downward trend of 0.05% per year were derived from measurements by the Active Cavity Radiometer Irradiance Monitor (ACRIM) experiment on the Solar Maximum Mission during 1980. Distinct temporary solar irradiance decreases associated with solar activity maxima were observed with a series of nine dips from April to October recurring at fairly regular intervals averaging 24 days. The decreases correlate inversely with sunspot area, 2800-MHz flux, and Zurich sunspot number. Dominant periods common to the irradiance and sunspot area power spectra link the irradiance decreases to sunspot flux deficit in solar active regions. Evidence of significant total irradiance modulation by facular flux excess is cited. A persistent radiative cycle of active regions consistent with the ACRIM irradiance results and the morphology of solar active regions was found. The pattern of regularly recurrent active region maxima between April and October suggests an asymmetry in solar activity generation during this period

  20. Measuring process and knowledge consistency

    DEFF Research Database (Denmark)

    Edwards, Kasper; Jensen, Klaes Ladeby; Haug, Anders

    2007-01-01

    When implementing configuration systems, knowledge about products and processes are documented and replicated in the configuration system. This practice assumes that products are specified consistently i.e. on the same rule base and likewise for processes. However, consistency cannot be taken...... for granted; rather the contrary, and attempting to implement a configuration system may easily ignite a political battle. This is because stakes are high in the sense that the rules and processes chosen may only reflect one part of the practice, ignoring a majority of the employees. To avoid this situation......, this paper presents a methodology for measuring product and process consistency prior to implementing a configuration system. The methodology consists of two parts: 1) measuring knowledge consistency and 2) measuring process consistency. Knowledge consistency is measured by developing a questionnaire...

  1. Variations in Solar Parameters and Cosmic Rays with Solar Magnetic Polarity

    Energy Technology Data Exchange (ETDEWEB)

    Oh, S. [Department of Earth Science Education, Chonnam National University, Gwangju, 61186 (Korea, Republic of); Yi, Y., E-mail: suyeonoh@jnu.ac.kr [Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, 34134 (Korea, Republic of)

    2017-05-01

    The sunspot number varies with the 11-year Schwabe cycle, and the solar magnetic polarity reverses every 11 years approximately at the solar maximum. Because of polarity reversal, the difference between odd and even solar cycles is seen in solar activity. In this study, we create the mean solar cycle expressed by phase using the monthly sunspot number for all solar cycles 1–23. We also generate the mean solar cycle for sunspot area, solar radio flux, and cosmic ray flux within the allowance of observational range. The mean solar cycle has one large peak at solar maximum for odd solar cycles and two small peaks for most even solar cycles. The odd and even solar cycles have the statistical difference in value and shape at a confidence level of at least 98%. For solar cycles 19–23, the second peak in the even solar cycle is larger than the first peak. This result is consistent with the frequent solar events during the declining phase after the solar maximum. The difference between odd and even solar cycles can be explained by a combined model of polarity reversal and solar rotation. In the positive/negative polarity, the polar magnetic field introduces angular momentum in the same/opposite direction as/to the solar rotation. Thus the addition/subtraction of angular momentum can increase/decrease the motion of plasma to support the formation of sunspots. Since the polarity reverses at the solar maximum, the opposite phenomenon occurs in the declining phase.

  2. Solar Energy.

    Science.gov (United States)

    Eaton, William W.

    Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

  3. Solar energy

    Science.gov (United States)

    Rapp, D.

    1981-01-01

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  4. Solar Combisystems

    DEFF Research Database (Denmark)

    Thür, Alexander

    2006-01-01

    This note first introduces what is a solar combisystem, the structure how a solar combisystem is build up and what are criteria’s to evaluate a solar combisystem concept. Further on the main components of a solar combisystem, the main characteristics and possible advantages and disadvantages...... compared to each other are described. It is not the goal of this note to explain the technical details how to design all components of a solar combisystem. This is done during other lectures of the solar course and in other basic courses as well. This note tries to explain how a solar combisystem...

  5. Solar Systems

    Science.gov (United States)

    1979-01-01

    The solar collectors shown are elements of domestic solar hot water systems produced by Solar One Ltd., Virginia Beach, Virginia. Design of these systems benefited from technical expertise provided Solar One by NASA's Langley Research Center. The company obtained a NASA technical support package describing the d e sign and operation of solar heating equipment in NASA's Tech House, a demonstration project in which aerospace and commercial building technology are combined in an energy- efficient home. Solar One received further assistance through personal contact with Langley solar experts. The company reports that the technical information provided by NASA influenced Solar One's panel design, its selection of a long-life panel coating which increases solar collection efficiency, and the method adopted for protecting solar collectors from freezing conditions.

  6. Solar radiophysics

    International Nuclear Information System (INIS)

    McLean, D.J.; Labrum, N.R.

    1985-01-01

    This book treats all aspects of solar radioastronomy at metre wavelengths, particularly work carried out on the Australian radioheliograph at Culgoora, with which most of the authors have been associated in one way or another. After an introductory section on historical aspects, the solar atmosphere, solar flares, and coronal radio emission, the book deals with instrumentation, theory, and details of observations and interpretations of the various aspects of metrewave solar radioastronomy, including burst types, solar storms, and the quiet sun. (U.K.)

  7. Consistency argued students of fluid

    Science.gov (United States)

    Viyanti; Cari; Suparmi; Winarti; Slamet Budiarti, Indah; Handika, Jeffry; Widyastuti, Fatma

    2017-01-01

    Problem solving for physics concepts through consistency arguments can improve thinking skills of students and it is an important thing in science. The study aims to assess the consistency of the material Fluid student argmentation. The population of this study are College students PGRI Madiun, UIN Sunan Kalijaga Yogyakarta and Lampung University. Samples using cluster random sampling, 145 samples obtained by the number of students. The study used a descriptive survey method. Data obtained through multiple-choice test and interview reasoned. Problem fluid modified from [9] and [1]. The results of the study gained an average consistency argmentation for the right consistency, consistency is wrong, and inconsistent respectively 4.85%; 29.93%; and 65.23%. Data from the study have an impact on the lack of understanding of the fluid material which is ideally in full consistency argued affect the expansion of understanding of the concept. The results of the study as a reference in making improvements in future studies is to obtain a positive change in the consistency of argumentations.

  8. Coordinating user interfaces for consistency

    CERN Document Server

    Nielsen, Jakob

    2001-01-01

    In the years since Jakob Nielsen's classic collection on interface consistency first appeared, much has changed, and much has stayed the same. On the one hand, there's been exponential growth in the opportunities for following or disregarding the principles of interface consistency-more computers, more applications, more users, and of course the vast expanse of the Web. On the other, there are the principles themselves, as persistent and as valuable as ever. In these contributed chapters, you'll find details on many methods for seeking and enforcing consistency, along with bottom-line analys

  9. Numerical consistency check between two approaches to radiative ...

    Indian Academy of Sciences (India)

    approaches for a consistency check on numerical accuracy, and find out the stabil- ... ln(MR/1 GeV) to top-quark mass scale t0(= ln(mt/1 GeV)) where t0 ≤ t ≤ tR, we ..... It is in general to tone down the solar mixing angle through further fine.

  10. Choice, internal consistency, and rationality

    OpenAIRE

    Aditi Bhattacharyya; Prasanta K. Pattanaik; Yongsheng Xu

    2010-01-01

    The classical theory of rational choice is built on several important internal consistency conditions. In recent years, the reasonableness of those internal consistency conditions has been questioned and criticized, and several responses to accommodate such criticisms have been proposed in the literature. This paper develops a general framework to accommodate the issues raised by the criticisms of classical rational choice theory, and examines the broad impact of these criticisms from both no...

  11. Self-consistent quark bags

    International Nuclear Information System (INIS)

    Rafelski, J.

    1979-01-01

    After an introductory overview of the bag model the author uses the self-consistent solution of the coupled Dirac-meson fields to represent a bound state of strongly ineteracting fermions. In this framework he discusses the vivial approach to classical field equations. After a short description of the used numerical methods the properties of bound states of scalar self-consistent Fields and the solutions of a self-coupled Dirac field are considered. (HSI) [de

  12. Time-consistent and market-consistent evaluations

    NARCIS (Netherlands)

    Pelsser, A.; Stadje, M.A.

    2014-01-01

    We consider evaluation methods for payoffs with an inherent financial risk as encountered for instance for portfolios held by pension funds and insurance companies. Pricing such payoffs in a way consistent to market prices typically involves combining actuarial techniques with methods from

  13. Large-scale solar heating

    Energy Technology Data Exchange (ETDEWEB)

    Tolonen, J.; Konttinen, P.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    Solar heating market is growing in many European countries and annually installed collector area has exceeded one million square meters. There are dozens of collector manufacturers and hundreds of firms making solar heating installations in Europe. One tendency in solar heating is towards larger systems. These can be roof integrated, consisting of some tens or hundreds of square meters of collectors, or they can be larger centralized solar district heating plants consisting of a few thousand square meters of collectors. The increase of size can reduce the specific investments of solar heating systems, because e.g. the costs of some components (controllers, pumps, and pipes), planning and installation can be smaller in larger systems. The solar heat output can also be higher in large systems, because more advanced technique is economically viable

  14. Solar saddle bags. Solar-Fahrradpacktaschen

    Energy Technology Data Exchange (ETDEWEB)

    Willems, M

    1991-09-12

    The invention consists of the arrangement of solar cells on the upper side of saddle bags of every design (handle bar pocket, bicycle saddle bag etc.) which charge the accumulators in the pack pocket. One can drive the alternator of the bicycle, a transistor radio, a cassette tape recorder, or similar, with the power from the accumulators. The lamp and the taillight of the bicycle can still be used. The solar cells can be attached firmly to the pack pocket. However, they can also be assembled detachably, e.g. by push-buttons or zip-fasteners.

  15. Market-consistent actuarial valuation

    CERN Document Server

    Wüthrich, Mario V

    2016-01-01

    This is the third edition of this well-received textbook, presenting powerful methods for measuring insurance liabilities and assets in a consistent way, with detailed mathematical frameworks that lead to market-consistent values for liabilities. Topics covered are stochastic discounting with deflators, valuation portfolio in life and non-life insurance, probability distortions, asset and liability management, financial risks, insurance technical risks, and solvency. Including updates on recent developments and regulatory changes under Solvency II, this new edition of Market-Consistent Actuarial Valuation also elaborates on different risk measures, providing a revised definition of solvency based on industry practice, and presents an adapted valuation framework which takes a dynamic view of non-life insurance reserving risk.

  16. The Principle of Energetic Consistency

    Science.gov (United States)

    Cohn, Stephen E.

    2009-01-01

    A basic result in estimation theory is that the minimum variance estimate of the dynamical state, given the observations, is the conditional mean estimate. This result holds independently of the specifics of any dynamical or observation nonlinearity or stochasticity, requiring only that the probability density function of the state, conditioned on the observations, has two moments. For nonlinear dynamics that conserve a total energy, this general result implies the principle of energetic consistency: if the dynamical variables are taken to be the natural energy variables, then the sum of the total energy of the conditional mean and the trace of the conditional covariance matrix (the total variance) is constant between observations. Ensemble Kalman filtering methods are designed to approximate the evolution of the conditional mean and covariance matrix. For them the principle of energetic consistency holds independently of ensemble size, even with covariance localization. However, full Kalman filter experiments with advection dynamics have shown that a small amount of numerical dissipation can cause a large, state-dependent loss of total variance, to the detriment of filter performance. The principle of energetic consistency offers a simple way to test whether this spurious loss of variance limits ensemble filter performance in full-blown applications. The classical second-moment closure (third-moment discard) equations also satisfy the principle of energetic consistency, independently of the rank of the conditional covariance matrix. Low-rank approximation of these equations offers an energetically consistent, computationally viable alternative to ensemble filtering. Current formulations of long-window, weak-constraint, four-dimensional variational methods are designed to approximate the conditional mode rather than the conditional mean. Thus they neglect the nonlinear bias term in the second-moment closure equation for the conditional mean. The principle of

  17. Consistent guiding center drift theories

    International Nuclear Information System (INIS)

    Wimmel, H.K.

    1982-04-01

    Various guiding-center drift theories are presented that are optimized in respect of consistency. They satisfy exact energy conservation theorems (in time-independent fields), Liouville's theorems, and appropriate power balance equations. A theoretical framework is given that allows direct and exact derivation of associated drift-kinetic equations from the respective guiding-center drift-orbit theories. These drift-kinetic equations are listed. Northrop's non-optimized theory is discussed for reference, and internal consistency relations of G.C. drift theories are presented. (orig.)

  18. Weak consistency and strong paraconsistency

    Directory of Open Access Journals (Sweden)

    Gemma Robles

    2009-11-01

    Full Text Available In a standard sense, consistency and paraconsistency are understood as, respectively, the absence of any contradiction and as the absence of the ECQ (“E contradictione quodlibet” rule that allows us to conclude any well formed formula from any contradiction. The aim of this paper is to explain the concepts of weak consistency alternative to the standard one, the concepts of paraconsistency related to them and the concept of strong paraconsistency, all of which have been defined by the author together with José M. Méndez.

  19. Consistent force fields for saccharides

    DEFF Research Database (Denmark)

    Rasmussen, Kjeld

    1999-01-01

    Consistent force fields for carbohydrates were hitherto developed by extensive optimization ofpotential energy function parameters on experimental data and on ab initio results. A wide range of experimental data is used: internal structures obtained from gas phase electron diffraction and from x......-anomeric effects are accounted for without addition of specific terms. The work is done in the framework of the Consistent Force Field which originatedin Israel and was further developed in Denmark. The actual methods and strategies employed havebeen described previously. Extensive testing of the force field...

  20. Glass consistency and glass performance

    International Nuclear Information System (INIS)

    Plodinec, M.J.; Ramsey, W.G.

    1994-01-01

    Glass produced by the Defense Waste Processing Facility (DWPF) will have to consistently be more durable than a benchmark glass (evaluated using a short-term leach test), with high confidence. The DWPF has developed a Glass Product Control Program to comply with this specification. However, it is not clear what relevance product consistency has on long-term glass performance. In this report, the authors show that DWPF glass, produced in compliance with this specification, can be expected to effectively limit the release of soluble radionuclides to natural environments. However, the release of insoluble radionuclides to the environment will be limited by their solubility, and not glass durability

  1. Solar energy

    International Nuclear Information System (INIS)

    Kruisheer, N.

    1992-01-01

    In five brief articles product information is given on solar energy applications with special attention to the Netherlands. After an introduction on solar energy availability in the Netherlands the developments in solar boiler techniques are dealt with. Solar water heaters have advantages for the environment, and government subsidies stimulate different uses of such water heaters. Also the developments of solar cells show good prospects, not only for developing countries, but also for the industrialized countries. In brief the developments in solar energy storage and the connection of solar equipment to the grid are discussed. Finally attention is paid to the applications of passive solar energy in the housing construction, the use of transparent thermal insulation and the developments of translucent materials. 18 figs., 18 ills

  2. Solar Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar photographic and illustrated datasets contributed by a number of national and private solar observatories located worldwide....

  3. Solar Features

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar feature datasets contributed by a number of national and private solar observatories located worldwide.

  4. Solar Indices

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  5. Time-consistent actuarial valuations

    NARCIS (Netherlands)

    Pelsser, A.A.J.; Salahnejhad Ghalehjooghi, A.

    2016-01-01

    Time-consistent valuations (i.e. pricing operators) can be created by backward iteration of one-period valuations. In this paper we investigate the continuous-time limits of well-known actuarial premium principles when such backward iteration procedures are applied. This method is applied to an

  6. Dynamically consistent oil import tariffs

    International Nuclear Information System (INIS)

    Karp, L.; Newbery, D.M.

    1992-01-01

    The standard theory of optimal tariffs considers tariffs on perishable goods produced abroad under static conditions, in which tariffs affect prices only in that period. Oil and other exhaustable resources do not fit this model, for current tariffs affect the amount of oil imported, which will affect the remaining stock and hence its future price. The problem of choosing a dynamically consistent oil import tariff when suppliers are competitive but importers have market power is considered. The open-loop Nash tariff is solved for the standard competitive case in which the oil price is arbitraged, and it was found that the resulting tariff rises at the rate of interest. This tariff was found to have an equilibrium that in general is dynamically inconsistent. Nevertheless, it is shown that necessary and sufficient conditions exist under which the tariff satisfies the weaker condition of time consistency. A dynamically consistent tariff is obtained by assuming that all agents condition their current decisions on the remaining stock of the resource, in contrast to open-loop strategies. For the natural case in which all agents choose their actions simultaneously in each period, the dynamically consistent tariff was characterized, and found to differ markedly from the time-inconsistent open-loop tariff. It was shown that if importers do not have overwhelming market power, then the time path of the world price is insensitive to the ability to commit, as is the level of wealth achieved by the importer. 26 refs., 4 figs

  7. Solar Special

    International Nuclear Information System (INIS)

    Van Roekel, A.; Osborne, J.; Schroeter, S.; De Jong, R.; De Saint Jacob, Y.

    2009-01-01

    Solar power is growing much faster than most policymakers and analysts realise. As costs come down and feed-in tariffs go up across Europe, a number of countries have started in pursuit of market leader Germany. But in Germany criticism is growing of the multi-billion-euro support schemes that keep the solar industry booming. In this section of the magazine several articles are dedicated to developments in solar energy in Europe. The first article is an overview story on the strong growing global market for solar cells, mainly thanks to subsidy schemes. The second article is on the position of foreign companies in the solar market in Italy. Article number three is dedicated to the conditions for solar technology companies to establish themselves in the German state of Saxony. Also the fifth article deals with the development of solar cells in Saxony: scientists, plant manufacturers and module producers in Saxony are working on new technologies that can be used to produce solar electricity cost-effectively. The goal is to bring the price down to match that of conventionally generated electricity within the next few years. The sixth article deals with the the solar power market in Belgium, which may be overheated or 'oversubsidized'. Article seven is on France, which used to be a pioneer in solar technology, but now produces only a fraction of the solar output of market leader Germany. However, new attractive feed-in-tariffs are changing the solar landscape drastically

  8. Consistently violating the non-Gaussian consistency relation

    International Nuclear Information System (INIS)

    Mooij, Sander; Palma, Gonzalo A.

    2015-01-01

    Non-attractor models of inflation are characterized by the super-horizon evolution of curvature perturbations, introducing a violation of the non-Gaussian consistency relation between the bispectrum's squeezed limit and the power spectrum's spectral index. In this work we show that the bispectrum's squeezed limit of non-attractor models continues to respect a relation dictated by the evolution of the background. We show how to derive this relation using only symmetry arguments, without ever needing to solve the equations of motion for the perturbations

  9. Solar Indices - Solar Radio Flux

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  10. Consistence of Network Filtering Rules

    Institute of Scientific and Technical Information of China (English)

    SHE Kun; WU Yuancheng; HUANG Juncai; ZHOU Mingtian

    2004-01-01

    The inconsistence of firewall/VPN(Virtual Private Network) rule makes a huge maintainable cost.With development of Multinational Company,SOHO office,E-government the number of firewalls/VPN will increase rapidly.Rule table in stand-alone or network will be increased in geometric series accordingly.Checking the consistence of rule table manually is inadequate.A formal approach can define semantic consistence,make a theoretic foundation of intelligent management about rule tables.In this paper,a kind of formalization of host rules and network ones for auto rule-validation based on SET theory were proporsed and a rule validation scheme was defined.The analysis results show the superior performance of the methods and demonstrate its potential for the intelligent management based on rule tables.

  11. Self-consistent radial sheath

    International Nuclear Information System (INIS)

    Hazeltine, R.D.

    1988-12-01

    The boundary layer arising in the radial vicinity of a tokamak limiter is examined, with special reference to the TEXT tokamak. It is shown that sheath structure depends upon the self-consistent effects of ion guiding-center orbit modification, as well as the radial variation of E /times/ B-induced toroidal rotation. Reasonable agreement with experiment is obtained from an idealized model which, however simplified, preserves such self-consistent effects. It is argued that the radial sheath, which occurs whenever confining magnetic field-lines lie in the plasma boundary surface, is an object of some intrinsic interest. It differs from the more familiar axial sheath because magnetized charges respond very differently to parallel and perpendicular electric fields. 11 refs., 1 fig

  12. Lagrangian multiforms and multidimensional consistency

    Energy Technology Data Exchange (ETDEWEB)

    Lobb, Sarah; Nijhoff, Frank [Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT (United Kingdom)

    2009-10-30

    We show that well-chosen Lagrangians for a class of two-dimensional integrable lattice equations obey a closure relation when embedded in a higher dimensional lattice. On the basis of this property we formulate a Lagrangian description for such systems in terms of Lagrangian multiforms. We discuss the connection of this formalism with the notion of multidimensional consistency, and the role of the lattice from the point of view of the relevant variational principle.

  13. Consistency and Communication in Committees

    OpenAIRE

    Inga Deimen; Felix Ketelaar; Mark T. Le Quement

    2013-01-01

    This paper analyzes truthtelling incentives in pre-vote communication in heterogeneous committees. We generalize the classical Condorcet jury model by introducing a new informational structure that captures consistency of information. In contrast to the impossibility result shown by Coughlan (2000) for the classical model, full pooling of information followed by sincere voting is an equilibrium outcome of our model for a large set of parameter values implying the possibility of ex post confli...

  14. Deep Feature Consistent Variational Autoencoder

    OpenAIRE

    Hou, Xianxu; Shen, Linlin; Sun, Ke; Qiu, Guoping

    2016-01-01

    We present a novel method for constructing Variational Autoencoder (VAE). Instead of using pixel-by-pixel loss, we enforce deep feature consistency between the input and the output of a VAE, which ensures the VAE's output to preserve the spatial correlation characteristics of the input, thus leading the output to have a more natural visual appearance and better perceptual quality. Based on recent deep learning works such as style transfer, we employ a pre-trained deep convolutional neural net...

  15. Coupled solar still, solar heater

    Energy Technology Data Exchange (ETDEWEB)

    Davison, R R; Harris, W B; Moor, D H; Delyannis, A; Delyannis, E [eds.

    1976-01-01

    Computer simulation of combinations of solar stills and solar heaters indicates the probable economic advantage of such an arrangement in many locations if the size of the heater is optimized relative to that of the still. Experience with various low cost solar heaters is discussed.

  16. Solar Sailing

    Science.gov (United States)

    Johnson, Les

    2009-01-01

    Solar sailing is a topic of growing technical and popular interest. Solar sail propulsion will make space exploration more affordable and offer access to destinations within (and beyond) the solar system that are currently beyond our technical reach. The lecture will describe solar sails, how they work, and what they will be used for in the exploration of space. It will include a discussion of current plans for solar sails and how advanced technology, such as nanotechnology, might enhance their performance. Much has been accomplished recently to make solar sail technology very close to becoming an engineering reality and it will soon be used by the world s space agencies in the exploration of the solar system and beyond. The first part of the lecture will summarize state-of-the-art space propulsion systems and technologies. Though these other technologies are the key to any deep space exploration by humans, robots, or both, solar-sail propulsion will make space exploration more affordable and offer access to distant and difficult destinations. The second part of the lecture will describe the fundamentals of space solar sail propulsion and will describe the near-, mid- and far-term missions that might use solar sails as a propulsion system. The third part of the lecture will describe solar sail technology and the construction of current and future sailcraft, including the work of both government and private space organizations.

  17. Liquid flat plate collector and pump for solar heating and cooling systems: A collection of quarterly reports

    Science.gov (United States)

    1978-01-01

    Progress in the development, fabrication, and delivery of solar subsystems consisting of a solar operated pump, and solar collectors which can be used in solar heating and cooling, or hot water, for single family, multifamily, or commercial applications is reported.

  18. Solar Water-Heater Design Package

    Science.gov (United States)

    1982-01-01

    Information on a solar domestic-hot water heater is contained in 146 page design package. System consists of solar collector, storage tanks, automatic control circuitry and auxiliary heater. Data-acquisition equipment at sites monitors day-by-day performance. Includes performance specifications, schematics, solar-collector drawings and drawings of control parts.

  19. Solar System Update

    CERN Document Server

    Blondel, Philippe

    2006-01-01

    This book, the first in a series of forthcoming volumes, consists of topical and timely reviews of a number of carefully selected topics in solar systemn science. Contributions, in form of up-to-date reviews, are mainly aimed at professional astronomers and planetary scientists wishing to inform themselves about progress in fields closely related to their own field of expertise.

  20. Solar proton fluxes since 1956

    International Nuclear Information System (INIS)

    Reedy, R.C.

    1977-01-01

    The fluxes of protons emitted during solar flares since 1956 were evaluated. The depth-versus-activity profiles of 56 Co in several lunar rocks are consistent with the solar-proton fluxes detected by experiments on several satellites. Only about 20% of the solar-proton-induced activities of 22 Na and 55 Fe in lunar rocks from early Apollo missions were produced by protons emitted from the sun during solar cycle 20 (1965--1975). The depth-versus-activity data for these radionuclides in several lunar rocks were used to determine the fluxes of protons during solar cycle 19 (1954--1964). The average proton fluxes for cycle 19 are about five times those for both the last million years and for cycle 20. These solar-proton flux variations correlate with changes in sunspot activity

  1. Maintaining consistency in distributed systems

    Science.gov (United States)

    Birman, Kenneth P.

    1991-01-01

    In systems designed as assemblies of independently developed components, concurrent access to data or data structures normally arises within individual programs, and is controlled using mutual exclusion constructs, such as semaphores and monitors. Where data is persistent and/or sets of operation are related to one another, transactions or linearizability may be more appropriate. Systems that incorporate cooperative styles of distributed execution often replicate or distribute data within groups of components. In these cases, group oriented consistency properties must be maintained, and tools based on the virtual synchrony execution model greatly simplify the task confronting an application developer. All three styles of distributed computing are likely to be seen in future systems - often, within the same application. This leads us to propose an integrated approach that permits applications that use virtual synchrony with concurrent objects that respect a linearizability constraint, and vice versa. Transactional subsystems are treated as a special case of linearizability.

  2. Solar Photovoltaic

    OpenAIRE

    Wang, Chen; Lu, Yuefeng

    2016-01-01

    In the 21st century, human demand for new energy sources is urgent, because the traditional fossil energy is unable to meet human needs, and the fossil resource will make pollution, in this situation, solar energy gradually into the vision of scientists. As science advances, humans can already extensive use of solar energy to generate electricity. Solar energy is an inexhaustible and clean energy. In the global energy crisis, environmental pollution is the growing problem of today. The us...

  3. Solar magnetohydrodynamics

    International Nuclear Information System (INIS)

    Priest, E.R.

    1982-01-01

    The book serves several purposes. First set of chapters gives a concise general introduction to solar physics. In a second set the basic methods of magnetohydrodynamics are developed. A third set of chapters is an account of current theories for observed phenomena. The book is suitable for a course in solar physics and it also provides a comprehensive review of present magnetohydrodynamical models in solar physics. (SC)

  4. Solar constraints

    International Nuclear Information System (INIS)

    Provost, J.

    1984-01-01

    Accurate tests of the theory of stellar structure and evolution are available from the Sun's observations. The solar constraints are reviewed, with a special attention to the recent progress in observing global solar oscillations. Each constraint is sensitive to a given region of the Sun. The present solar models (standard, low Z, mixed) are discussed with respect to neutrino flux, low and high degree five-minute oscillations and low degree internal gravity modes. It appears that actually there do not exist solar models able to fully account for all the observed quantities. (Auth.)

  5. Solar Simulator

    Science.gov (United States)

    1981-01-01

    Oriel Corporation's simulators have a high pressure xenon lamp whose reflected light is processed by an optical system to produce a uniform solar beam. Because of many different types of applications, the simulators must be adjustable to replicate many different areas of the solar radiation spectrum. Simulators are laboratory tools for such purposes as testing and calibrating solar cells, or other solar energy systems, testing dyes, paints and pigments, pharmaceuticals and cosmetic preparations, plant and animal studies, food and agriculture studies and oceanographic research.

  6. Decentralized Consistent Updates in SDN

    KAUST Repository

    Nguyen, Thanh Dang

    2017-04-10

    We present ez-Segway, a decentralized mechanism to consistently and quickly update the network state while preventing forwarding anomalies (loops and blackholes) and avoiding link congestion. In our design, the centralized SDN controller only pre-computes information needed by the switches during the update execution. This information is distributed to the switches, which use partial knowledge and direct message passing to efficiently realize the update. This separation of concerns has the key benefit of improving update performance as the communication and computation bottlenecks at the controller are removed. Our evaluations via network emulations and large-scale simulations demonstrate the efficiency of ez-Segway, which compared to a centralized approach, improves network update times by up to 45% and 57% at the median and the 99th percentile, respectively. A deployment of a system prototype in a real OpenFlow switch and an implementation in P4 demonstrate the feasibility and low overhead of implementing simple network update functionality within switches.

  7. Installation package for a domestic solar heating and hot water system

    Science.gov (United States)

    1978-01-01

    The installation of two prototype solar heating and hot water systems is described. The systems consists of the following subsystems: solar collector, storage, control, transport, and auxiliary energy.

  8. Radiochemical solar neutrino experiments

    International Nuclear Information System (INIS)

    Rich, R.; Spiro, M.

    1993-01-01

    This review covers the three presently running radiochemical solar neutrino experiments, namely the Chlorine, SAGE, and GALLEX experiments. The focus of the review is on a discussion of statistical consistency checks of the available data. The chlorine radiochemical experiment is conceptually simple and shows no strong indication of any statistical anomalies. It still forms the basis of the solar neutrino problem. Each of the two gallium experiments show internal statistical consistency. SAGE's recent preliminary results are consistent with the published GALLEX results. If this convergence is confirmed by a more definitive analysis, this would suggest that the combined result of the two gallium experiments, SAGE and GALLEX, be used for comparisons with theoretical expectations. 5 refs., 15 figs

  9. Solar cooking

    Science.gov (United States)

    Over two billion people face fuel wood shortages, causing tremendous personal and environmental stress. Over 4 million people die prematurely from indoor air pollution. Solar cooking can reduce fuel wood consumption and indoor air pollution. Solar cooking has been practiced and published since th...

  10. Solar Sprint

    Science.gov (United States)

    Tabor, Richard; Anderson, Stephen

    2007-01-01

    In the "Solar Sprint" activity, students design, test, and race a solar-powered car built with Legos. The use of ratios is incorporated to simulate the actual work of scientists and engineers. This method encourages fourth-grade students to think about multiple variables and stimulates their curiosity when an activity doesn't come out as…

  11. SOLAR-ISS: A new reference spectrum based on SOLAR/SOLSPEC observations

    Science.gov (United States)

    Meftah, M.; Damé, L.; Bolsée, D.; Hauchecorne, A.; Pereira, N.; Sluse, D.; Cessateur, G.; Irbah, A.; Bureau, J.; Weber, M.; Bramstedt, K.; Hilbig, T.; Thiéblemont, R.; Marchand, M.; Lefèvre, F.; Sarkissian, A.; Bekki, S.

    2018-03-01

    Context. Since April 5, 2008 and up to February 15, 2017, the SOLar SPECtrometer (SOLSPEC) instrument of the SOLAR payload on board the International Space Station (ISS) has performed accurate measurements of solar spectral irradiance (SSI) from the middle ultraviolet to the infrared (165 to 3088 nm). These measurements are of primary importance for a better understanding of solar physics and the impact of solar variability on climate. In particular, a new reference solar spectrum (SOLAR-ISS) is established in April 2008 during the solar minima of cycles 23-24 thanks to revised engineering corrections, improved calibrations, and advanced procedures to account for thermal and aging corrections of the SOLAR/SOLSPEC instrument. Aims: The main objective of this article is to present a new high-resolution solar spectrum with a mean absolute uncertainty of 1.26% at 1σ from 165 to 3000 nm. This solar spectrum is based on solar observations of the SOLAR/SOLSPEC space-based instrument. Methods: The SOLAR/SOLSPEC instrument consists of three separate double monochromators that use concave holographic gratings to cover the middle ultraviolet (UV), visible (VIS), and infrared (IR) domains. Our best ultraviolet, visible, and infrared spectra are merged into a single absolute solar spectrum covering the 165-3000 nm domain. The resulting solar spectrum has a spectral resolution varying between 0.6 and 9.5 nm in the 165-3000 nm wavelength range. We build a new solar reference spectrum (SOLAR-ISS) by constraining existing high-resolution spectra to SOLAR/SOLSPEC observed spectrum. For that purpose, we account for the difference of resolution between the two spectra using the SOLAR/SOLSPEC instrumental slit functions. Results: Using SOLAR/SOLSPEC data, a new solar spectrum covering the 165-3000 nm wavelength range is built and is representative of the 2008 solar minimum. It has a resolution better than 0.1 nm below 1000 nm and 1 nm in the 1000-3000 nm wavelength range. The new

  12. A novel design for a cheap high temperature solar collector: The rotating solar boiler

    NARCIS (Netherlands)

    Luijtelaer, van J.P.H.; Kroon, M.C.

    2009-01-01

    In this work a novel type of high temperature solar collector is designed: the rotating solar boiler. This rotating solar boiler consists of two concentric tubes. The inner tube, called absorber, absorbs sunlight and boils water. The outer transparent tube, called cover, is filled with air. The

  13. Solar thermal

    International Nuclear Information System (INIS)

    Jones, J.

    2006-01-01

    While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m 3 - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become increasingly important as

  14. Solar thermal

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J.

    2006-07-15

    While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m{sup 3} - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become

  15. Solar energy: photovoltaics

    International Nuclear Information System (INIS)

    Goetzberger, A.; Voss, B.; Knobloch, J.

    1994-01-01

    This textbooks covers the following topics: foundations of photovoltaics, solar energy, P-N junctions, physics of solar cells, high-efficiency solar cells, technology of Si solar cells, other solar cells, photovoltaic applications. (orig.)

  16. Passive solar heating

    Energy Technology Data Exchange (ETDEWEB)

    Wiberg, K

    1981-11-10

    The present work treats the possibilities for heating according to the passive solar heating method. Problems of 'spatial organization in an energy-saving society' are distinguished from among other social problems. The final delimination of the actual problems under investigation consists of the use of passive solar heating and especially the 'consequences of such solar heating exploitation upon the form and structures' of planning and construction. In the concluding chapter an applied example shows how this method can be used in designing an urban area and what are its limitations. The results indicate the possibilities and difficulties in attempting to transfer this ideal and general method into models and directives for form and structure from which examples of the actual possibilities in practical planning can be given.

  17. Proton solar flares

    International Nuclear Information System (INIS)

    Shaposhnikova, E.F.

    1979-01-01

    The observations of proton solar flares have been carried out in 1950-1958 using the extrablackout coronograph of the Crimea astrophysical observatory. The experiments permit to determine two characteristic features of flares: the directed motion of plasma injection flux from the solar depths and the appearance of a shock wave moving from the place of the injection along the solar surface. The appearance of the shock wave is accompanied by some phenomena occuring both in the sunspot zone and out of it. The consistent flash of proton flares in the other groups of spots, the disappearance of fibres and the appearance of eruptive prominences is accomplished in the sunspot zone. Beyond the sunspot zone the flares occur above spots, the fibres disintegrate partially or completely and the eruptive prominences appear in the regions close to the pole

  18. Solar Newsletter | Solar Research | NREL

    Science.gov (United States)

    more about work by this consortium, which crosses national laboratories, on new materials and designs information on NREL's research and development of solar technologies. To receive new issues by email prize, focused on solar energy technologies, and will release the prize rules and open registration

  19. Solar electricity and solar fuels

    Science.gov (United States)

    Spiers, David J.

    1989-04-01

    The nature of solar radiation and its variation with location is described. The distribution of energy in the solar spectrum places immediate limits on the theoretical efficiency of conversion processes, since practical absorbers cannot convert all wavelengths received to useful energy. The principles of solar energy conversion methods are described. Absorption of solar energy can give rise to direct electrical generation, heating, or chemical change. Electrical generation from sunlight can be achieved by photovoltaic systems directly or by thermal systems which use solar heat to drive a heat engine and generator. The technology used and under research for promising ways of producing electricity or fuel from solar energy is described. Photovoltaic technology is established today for remote area, small power applications, and photovoltaic module sales alone are over 100 million dollars per year at present. The photovoltaic market has grown steadily since the mid-1970's, as prices have fallen continuously. Future energy options are briefly described. The merits of a sustainable energy economy, based on renewable energy resources, including solar energy, are emphasized, as this seems to provide the only hope of eliminating the problems caused by the build-up of atmospheric carbon dioxide, acid rain pollution and nuclear waste disposal. There is no doubt that clean fuels which were derived from solar energy and either did not involve carbon dioxide and used atmospheric carbon dioxide as the source dioxide as the source of carbon would be a worthy ideal. Methods described could one day achieve this.

  20. Development and basic photovoltaic characteristics of a solar generator with double-sided silicon cells

    International Nuclear Information System (INIS)

    Aliev, R.; Mansurov, Kh.

    2015-01-01

    A new solar generator consisting of double-sided silicon sensing elements is described. The basic photovoltaic parameters of solar generators are made of mono- and polycrystalline silicon solar cells. (author)

  1. Solar magnetohydrodynamics

    International Nuclear Information System (INIS)

    Priest, E.R.

    1982-01-01

    Solar MHD is an important tool for understanding many solar phenomena. It also plays a crucial role in explaining the behaviour of more general cosmical magnetic fields and plasmas, since the Sun provides a natural laboratory in which such behaviour may be studied. While terrestrial experiments are invaluable in demonstrating general plasma properties, conclusions from them cannot be applied uncritically to solar plasmas and have in the past given rise to misconceptions about solar magnetic field behaviour. Important differences between a laboratory plasma on Earth and the Sun include the nature of boundary conditions, the energy balance, the effect of gravity and the size of the magnetic Reynolds number (generally of order unity on the Earth and very much larger on the Sun). The overall structure of the book is as follows. It begins with two introductory chapters on solar observations and the MHD equations. Then the fundamentals of MHD are developed in chapters on magnetostatics, waves, shocks, and instabilities. Finally, the theory is applied to the solar phenomena of atmospheric heating, sunspots, dynamos, flares, prominences, and the solar wind. (Auth.)

  2. Evolution of the solar system in the presence of a solar companion star

    International Nuclear Information System (INIS)

    Hut, P.

    1986-01-01

    A review is presented of the dynamical implications of a companion star in a wide orbit around the sun, with a semimajor axis of about half a parsec. The motivation behind the hypothesis of a solar companion star is reviewed briefly along with alternative hypotheses, and the general problem of solar system dynamics with a solar companion star is discussed. Four principal questions are posed and answered concerning the consistency of the solar companion theory in providing the required modulation in comet arrival times: (1) What is the expected lifetime of a solar companion? (2) How stable is the orbital period? (3) Does a single perihelion passage of a solar companion perturb enough comets? (4) Do repeated perihelion passages of a solar companion perturb too many comets? Some applications outside the solar system involving wide binaries, interstellar clouds, and dark matter in the Galactic disk are discussed, and the viability of the solar companion theory is critically assessed

  3. Solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Hullmann, H; Schmidt, B [Technische Univ. Hannover (Germany, F.R.). Inst. fuer Industrialisierung des Bauens

    1976-01-01

    The utilisation possibilities of solar energy for the energy supplying of buildings are becoming increasingly more significant. Solar research at the moment aims predominantly with a high level of efficiency and therefore making accessible a significant range of applications for solar technology. Parallel to this are attempts to effect the saving of energy, be it in the demand for energy-saving constructions or in the increasing development and application of rational energy utilisation by technologists. The most important point of these activities at the moment, is still technological methods.

  4. Solar neutrinos

    International Nuclear Information System (INIS)

    Schatzman, E.

    1983-01-01

    The solar energy is produced by a series of nuclear reactions taking place in the deep interior of the sun. Some of these reactions produce neutrinos which may be detected, the proper detection system being available. The results of the Davis experiment (with 37 Cl) are given, showing a deficiency in the solar neutrino flux. The relevant explanation is either a property of the neutrino or an important change in the physics of the solar models. The prospect of a new experiment (with 71 Ga) is important as it will decide which of the two explanations is correct [fr

  5. Concentrating Solar Power Projects - Planta Solar 20 | Concentrating Solar

    Science.gov (United States)

    Power | NREL 20 This page provides information on Planta Solar 20, a concentrating solar power Solar's Planta Solar 20 (PS20) is a 20-megawatt power tower plant being constructed next to the PS10 tower and increasing incident solar radiation capture will increase net electrical power output by 10

  6. Solar prominences

    CERN Document Server

    Engvold, Oddbjørn

    2015-01-01

    This volume presents the latest research results on solar prominences, including new developments on e.g. chirality, fine structure, magnetism, diagnostic tools and relevant solar plasma physics. In 1875 solar prominences, as seen out of the solar limb, were described by P.A. Secchi in his book Le Soleil as "gigantic pink or peach-flower coloured flames". The development of spectroscopy, coronagraphy and polarimetry brought tremendous observational advances in the twentieth century. The authors present and discuss exciting new challenges (resulting from observations made by space and ground-based telescopes in the 1990s and the first decade of the 21st century) concerning the diagnostics of prominences, their formation, their life time and their eruption along with their impact in the heliosphere (including the Earth). The book starts with a general introduction of the prominence “object” with some historical background on observations and instrumentation. In the next chapter, the various forms of promine...

  7. Solar chulha

    Energy Technology Data Exchange (ETDEWEB)

    Jadhao, P. H. [Department of Physics J.D. Institute of Engg. & Tech. Yavatmal (India); Patrikar, S. R. [Department of Physics VNIT, Nagpur (India)

    2016-05-06

    The main goal of the proposed system is to transfer energy from sun to the cooking load that is located in the kitchen. The energy is first collected by the solar collector lens system and two curve bars of same radius of curvature are mounted parallel and adjacent to each other at different height the solar collector is clamed on this two bars such that solar collector is exactly perpendicular to sunlight. The topology includes an additional feature which is window in the wall through which the beam is collimated is directed in the of kitchen. The solar energy that is collected is directed by the mirror system into the kitchen, where it is redirected to cooking platform located in the kitchen. The special feature in this system full Indian meal can be made since cooking platform is indoors.

  8. Solar Radio

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientists monitor the structure of the solar corona, the outer most regions of the Sun's atmosphere, using radio waves (100?s of MHz to 10?s of GHz). Variations in...

  9. Solar Energy

    Science.gov (United States)

    Building Design and Construction, 1977

    1977-01-01

    Describes 21 completed projects now using solar energy for heating, cooling, or electricity. Included are elementary schools in Atlanta and San Diego, a technical school in Detroit, and Trinity University in San Antonio, Texas. (MLF)

  10. Solar Pump

    Science.gov (United States)

    Pique, Charles

    1987-01-01

    Proposed pump moves liquid by action of bubbles formed by heat of sun. Tube of liquid having boiling point of 100 to 200 degrees F placed at focal axis of cylindrical reflector. Concentrated sunlight boils liquid at focus, and bubbles of vapor rise in tube, carrying liquid along with them. Pressure difference in hot tube sufficient to produce flow in large loop. Used with conventional flat solar heating panel in completely solar-powered heat-storage system.

  11. Solar Schematic

    Science.gov (United States)

    1979-01-01

    The home shown at right is specially designed to accommodate solar heating units; it has roof planes in four directions, allowing placement of solar collectors for best exposure to the sun. Plans (bottom) and complete working blueprints for the solar-heated house are being marketed by Home Building Plan Service, Portland, Oregon. The company also offers an inexpensive schematic (center) showing how a homeowner only moderately skilled in the use of tools can build his own solar energy system, applicable to new or existing structures. The schematic is based upon the design of a low-cost solar home heating system built and tested by NASA's Langley Research Center; used to supplement a warm-air heating system, it can save the homeowner about 40 percent of his annual heating bill for a modest investment in materials and components. Home Building Plan Service saved considerable research time by obtaining a NASA technical report which details the Langley work. The resulting schematic includes construction plans and simplified explanations of solar heat collection, collectors and other components, passive heat factors, domestic hot water supply and how to work with local heating engineers.

  12. Solar Powered Remediation and pH Control

    Science.gov (United States)

    2017-04-13

    zone. The PRT system was completely powered via an off-the-grid solar power system . The system consisted of four 85 watt photovoltaic solar panels...polarity of the proton reduction system can be periodically alternated (i.e., the anode becomes a cathode) to increase the size of the treatment area, to...PRT System The PRT system was completely powered via an off-the-grid solar power system . The system consisted of four 85 watt photovoltaic solar

  13. Multi-kW solar arrays for Earth orbit applications

    Science.gov (United States)

    1985-01-01

    The multi-kW solar array program is concerned with developing the technology required to enable the design of solar arrays required to power the missions of the 1990's. The present effort required the design of a modular solar array panel consisting of superstrate modules interconnected to provide the structural support for the solar cells. The effort was divided into two tasks: (1) superstrate solar array panel design, and (2) superstrate solar array panel-to-panel design. The primary objective was to systematically investigate critical areas of the transparent superstrate solar array and evaluate the flight capabilities of this low cost approach.

  14. Solar India - 82: national solar energy convention

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    This document is the proceedings of the Solar India - 82 conference, which was held 17-19 December 1982. The papers are organized into functional groupings which include: (1) solar radiation, (2) flat plate solar collectors and solar water heaters, (3) solar concentrators, (4) solar air heaters and dryers, (5) solar ponds and energy storage, (6) solar cookers, (7) solar stills, (8) selective coatings, (9) photovoltaics, (10) space heating and cooling, (11) bio-energy, and (12) miscellaneous papers. The vast majority of the papers describe work carried out in India, the vast majority of the papers also contain relatively readable abstracts.

  15. Solar Features - Solar Flares - Patrol

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The H-alpha Flare Patrol identifies time periods each day when the sun is being continuously monitored by select ground-based solar observatories.

  16. Solar Features - Solar Flares - SIDS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A Sudden Ionospheric Disturbance (SID) is any of several radio propagation anomalies due to ionospheric changes resulting from solar or geophysical events.

  17. Solar Energy Innovation Network | Solar Research | NREL

    Science.gov (United States)

    Energy Innovation Network Solar Energy Innovation Network The Solar Energy Innovation Network grid. Text version The Solar Energy Innovation Network is a collaborative research effort administered (DOE) Solar Energy Technologies Office to develop and demonstrate new ways for solar energy to improve

  18. Solar atmosphere wave dynamics generated by solar global oscillating eigenmodes

    Science.gov (United States)

    Griffiths, M. K.; Fedun, V.; Erdélyi, R.; Zheng, R.

    2018-01-01

    The solar atmosphere exhibits a diverse range of wave phenomena, where one of the earliest discovered was the five-minute global acoustic oscillation, also referred to as the p-mode. The analysis of wave propagation in the solar atmosphere may be used as a diagnostic tool to estimate accurately the physical characteristics of the Sun's atmospheric layers. In this paper, we investigate the dynamics and upward propagation of waves which are generated by the solar global eigenmodes. We report on a series of hydrodynamic simulations of a realistically stratified model of the solar atmosphere representing its lower region from the photosphere to low corona. With the objective of modelling atmospheric perturbations, propagating from the photosphere into the chromosphere, transition region and low corona, generated by the photospheric global oscillations the simulations use photospheric drivers mimicking the solar p-modes. The drivers are spatially structured harmonics across the computational box parallel to the solar surface. The drivers perturb the atmosphere at 0.5 Mm above the bottom boundary of the model and are placed coincident with the location of the temperature minimum. A combination of the VALIIIC and McWhirter solar atmospheres are used as the background equilibrium model. We report how synthetic photospheric oscillations may manifest in a magnetic field free model of the quiet Sun. To carry out the simulations, we employed the magnetohydrodynamics code, SMAUG (Sheffield MHD Accelerated Using GPUs). Our results show that the amount of energy propagating into the solar atmosphere is consistent with a model of solar global oscillations described by Taroyan and Erdélyi (2008) using the Klein-Gordon equation. The computed results indicate a power law which is compared to observations reported by Ireland et al. (2015) using data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly.

  19. Competitive solar heating systems for residential buildings

    DEFF Research Database (Denmark)

    Furbo, Simon; Thür, Alexander; Fiedler, Frank

    2005-01-01

    The paper describes the ongoing research project “Competitive solar heating systems for residential buildings”. The aim of the project is to develop competitive solar combisystems which are attractive to buyers. The solar combisystems must be attractive compared to traditional energy systems, both....... In Denmark and Norway the focus is on solar heating/natural gas systems, and in Sweden and Latvia the focus is on solar heating/pellet systems. Additionally, Lund Institute of Technology and University of Oslo are studying solar collectors of various types being integrated into the roof and facade......, are the universities: Technical University of Denmark, Dalarna University, University of Oslo, Riga Technical University and Lund Institute of Technology, as well as the companies: Metro Therm A/S (Denmark), Velux A/S (Denmark), Solentek AB (Sweden) and SolarNor (Norway). The project consists of a number of Ph...

  20. Solar array technology evaluation program for SEPS (Solar Electrical Propulsion Stage)

    Science.gov (United States)

    1974-01-01

    An evaluation of the technology and the development of a preliminary design for a 25 kilowatt solar array system for solar electric propulsion are discussed. The solar array has a power to weight ratio of 65 watts per kilogram. The solar array system is composed of two wings. Each wing consists of a solar array blanket, a blanket launch storage container, an extension/retraction mast assembly, a blanket tensioning system, an array electrical harness, and hardware for supporting the system for launch and in the operating position. The technology evaluation was performed to assess the applicable solar array state-of-the-art and to define supporting research necessary to achieve technology readiness for meeting the solar electric propulsion system solar array design requirements.

  1. Solar energy. [New Zealand

    Energy Technology Data Exchange (ETDEWEB)

    Benseman, R.

    1977-10-15

    The potential for solar space heating and solar water heating in New Zealand is discussed. Available solar energy in New Zealand is indicated, and the economics of solar space and water heating is considered. (WHK)

  2. ISS Solar Array Management

    Science.gov (United States)

    Williams, James P.; Martin, Keith D.; Thomas, Justin R.; Caro, Samuel

    2010-01-01

    The International Space Station (ISS) Solar Array Management (SAM) software toolset provides the capabilities necessary to operate a spacecraft with complex solar array constraints. It monitors spacecraft telemetry and provides interpretations of solar array constraint data in an intuitive manner. The toolset provides extensive situational awareness to ensure mission success by analyzing power generation needs, array motion constraints, and structural loading situations. The software suite consists of several components including samCS (constraint set selector), samShadyTimers (array shadowing timers), samWin (visualization GUI), samLock (array motion constraint computation), and samJet (attitude control system configuration selector). It provides high availability and uptime for extended and continuous mission support. It is able to support two-degrees-of-freedom (DOF) array positioning and supports up to ten simultaneous constraints with intuitive 1D and 2D decision support visualizations of constraint data. Display synchronization is enabled across a networked control center and multiple methods for constraint data interpolation are supported. Use of this software toolset increases flight safety, reduces mission support effort, optimizes solar array operation for achieving mission goals, and has run for weeks at a time without issues. The SAM toolset is currently used in ISS real-time mission operations.

  3. Solar unit

    Energy Technology Data Exchange (ETDEWEB)

    Sukhanov, A M; Trushevskiy, S N; Tveryanovich, E V

    1982-01-01

    A solar unit is proposed which contains an inclined solar collector with supply and outlet pipelines, the first of which is connected to the source of a heat carrier, while the second is connected through the valve to the tank for collecting heated heat carrier equipped with a device for recovery. In order to improve the effectiveness of heating the heat carrier, it additionally contains a concentrator of solar radiation and a device for maintaining a level of the heat carrier in the collector in the zone of the focal spot of the concentrator, while the heat pipeline is connected to the source of the heat carrier with the help of a device for maintaining the level of the heat carrier.

  4. Solar neutrinos

    International Nuclear Information System (INIS)

    Phillips, R.J.N.

    1987-09-01

    The problem with solar neutrinos is that there seem to be too few of them, at least near the top end of the spectrum, since the 37 Cl detector finds only about 35% of the standard predicted flux. Various kinds of explanation have been offered: (a) the standard solar model is wrong, (b) neutrinos decay, (c) neutrinos have magnetic moments, (d) neutrinos oscillate. The paper surveys developments in each of these areas, especially the possible enhancement of neutrino oscillations by matter effects and adiabatic level crossing. The prospects for further independent experiments are also discussed. (author)

  5. Concentrating Solar Power Projects - Nevada Solar One | Concentrating Solar

    Science.gov (United States)

    Power | NREL Nevada Solar One This page provides information on Nevada Solar One, a concentrating solar power (CSP) project, with data organized by background, participants, and power plant configuration. Acciona Energy's Nevada Solar One is the third largest CSP plant in the world and the first plant

  6. Concentrating Solar Power Projects - Khi Solar One | Concentrating Solar

    Science.gov (United States)

    Power | NREL Khi Solar One This page provides information on Khi Solar One, a concentrating solar power (CSP) project, with data organized by background, parcipants and power plant configuration . Status Date: February 8, 2016 Project Overview Project Name: Khi Solar One Country: South Africa Location

  7. Solar Energy and You.

    Science.gov (United States)

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    This booklet provides an introduction to solar energy by discussing: (1) how a home is heated; (2) how solar energy can help in the heating process; (3) the characteristics of passive solar houses; (4) the characteristics of active solar houses; (5) how solar heat is stored; and (6) other uses of solar energy. Also provided are 10 questions to…

  8. Sistema Solar

    OpenAIRE

    Federación de Asociaciones de Astronomía Cielo de Comellas

    2011-01-01

    Lección sobre el Sistema Solar. Curso de Astronomía Básica, segunda edición, impartido por los miembros de la Federación de Asociaciones de Astronomía Cielo de Comellas. Casa de la Ciencia, sábados, del 24 de septiembre al 22 de octubre de 2011

  9. Solar Neutrinos

    Directory of Open Access Journals (Sweden)

    V. Antonelli

    2013-01-01

    relevant indications on the fundamental interactions among particles. After reviewing the striking results of the last two decades, which were determinant to solve the long standing solar neutrino puzzle and refine the Standard Solar Model, we focus our attention on the more recent results in this field and on the experiments presently running or planned for the near future. The main focus at the moment is to improve the knowledge of the mass and mixing pattern and especially to study in detail the lowest energy part of the spectrum, which represents most of the solar neutrino spectrum but is still a partially unexplored realm. We discuss this research project and the way in which present and future experiments could contribute to make the theoretical framework more complete and stable, understanding the origin of some “anomalies” that seem to emerge from the data and contributing to answer some present questions, like the exact mechanism of the vacuum to matter transition and the solution of the so-called solar metallicity problem.

  10. Solar satellites

    Energy Technology Data Exchange (ETDEWEB)

    Poher, C.

    1982-01-01

    A reference system design, projected costs, and the functional concepts of a satellite solar power system (SSPS) for converting sunlight falling on solar panels of a satellite in GEO to a multi-GW beam which could be received by a rectenna on earth are outlined. Electricity transmission by microwaves has been demonstrated, and a reference design system for supplying 5 GW dc to earth was devised. The system will use either monocrystalline Si or concentrator GaAs solar cells for energy collection in GEO. Development is still needed to improve the lifespan of the cells. Currently, the cell performance degrades 50 percent in efficiency after 7-8 yr in space. Each SSPS satellite would weigh either 34,000 tons (Si) or 51,000 tons (GaAs), thereby requiring the fabrication of a heavy lift launch vehicle or a single-stage-to-orbit transport in order to minimize launch costs. Costs for the solar panels have been estimated at $500/kW using the GaAs technology, with transport costs for materials to GEO being $40/kg.

  11. Solar Neutrinos

    Indian Academy of Sciences (India)

    7,81. The Chlorine experiment, located in the Homestake Gold Mine in Lead, South Dakota, was the first solar neutrino experiment to be set up. A tank of. 105 gallons of perchloroethylene in which the electron neu- trino reacts with chlorine to ...

  12. Solar satellites

    Science.gov (United States)

    Poher, C.

    A reference system design, projected costs, and the functional concepts of a satellite solar power system (SSPS) for converting sunlight falling on solar panels of a satellite in GEO to a multi-GW beam which could be received by a rectenna on earth are outlined. Electricity transmission by microwaves has been demonstrated, and a reference design system for supplying 5 GW dc to earth was devised. The system will use either monocrystalline Si or concentrator GaAs solar cells for energy collection in GEO. Development is still needed to improve the lifespan of the cells. Currently, the cell performance degrades 50 percent in efficiency after 7-8 yr in space. Each SSPS satellite would weigh either 34,000 tons (Si) or 51,000 tons (GaAs), thereby requiring the fabrication of a heavy lift launch vehicle or a single-stage-to-orbit transport in order to minimize launch costs. Costs for the solar panels have been estimated at $500/kW using the GaAs technology, with transport costs for materials to GEO being $40/kg.

  13. Prototype solar heating and hot water system

    Science.gov (United States)

    1977-01-01

    Progress is reported in the development of a solar heating and hot water system which uses a pyramidal optics solar concentrator for heating, and consists of the following subsystems: collector, control, transport, and site data acquisition. Improvements made in the components and subsystems are discussed.

  14. Circuits in the Sun: Solar Panel Physics

    Science.gov (United States)

    Gfroerer, Tim

    2013-01-01

    Typical commercial solar panels consist of approximately 60 individual photovoltaic cells connected in series. Since the usual Kirchhoff rules apply, the current is uniform throughout the circuit, while the electric potential of the individual devices is cumulative. Hence, a solar panel is a good analog of a simple resistive series circuit, except…

  15. ACHIEVING CONSISTENT DOPPLER MEASUREMENTS FROM SDO /HMI VECTOR FIELD INVERSIONS

    International Nuclear Information System (INIS)

    Schuck, Peter W.; Antiochos, S. K.; Leka, K. D.; Barnes, Graham

    2016-01-01

    NASA’s Solar Dynamics Observatory is delivering vector magnetic field observations of the full solar disk with unprecedented temporal and spatial resolution; however, the satellite is in a highly inclined geosynchronous orbit. The relative spacecraft–Sun velocity varies by ±3 km s −1 over a day, which introduces major orbital artifacts in the Helioseismic Magnetic Imager (HMI) data. We demonstrate that the orbital artifacts contaminate all spatial and temporal scales in the data. We describe a newly developed three-stage procedure for mitigating these artifacts in the Doppler data obtained from the Milne–Eddington inversions in the HMI pipeline. The procedure ultimately uses 32 velocity-dependent coefficients to adjust 10 million pixels—a remarkably sparse correction model given the complexity of the orbital artifacts. This procedure was applied to full-disk images of AR 11084 to produce consistent Dopplergrams. The data adjustments reduce the power in the orbital artifacts by 31 dB. Furthermore, we analyze in detail the corrected images and show that our procedure greatly improves the temporal and spectral properties of the data without adding any new artifacts. We conclude that this new procedure makes a dramatic improvement in the consistency of the HMI data and in its usefulness for precision scientific studies.

  16. Ayres' bifurcated solar model

    International Nuclear Information System (INIS)

    Kalkofen, W.

    1985-01-01

    The assumptions of Ayres' model of the upper solar atmosphere are examined. It is found that the bistable character of his model is postulated - through the assumptions concerning the opacity sources and the effect of mechanical waves, which are allowed to destroy the CO molecules but not to heat the gas. The neglect of cooling by metal lines is based on their reduced local cooling rate, but it ignores the increased depth over which this cooling occurs. Thus, the bifurcated model of the upper solar atmosphere consists of two models, one cold at the temperature minimum, with a kinetic temperature of 2900 K, and the other hot, with a temperature of 4900 K. 8 references

  17. Single-axle, double-axis solar tracker

    Science.gov (United States)

    Brantley, L. W.; Lawson, B. D.

    1979-01-01

    Solar concentrator tracking mechanism consisting of angular axle and two synchronized drive motors, follows seasonal as well as diurnal changes in earth's orientation with respect to incoming sunlight.

  18. Consistency Anchor Formalization and Correctness Proofs

    OpenAIRE

    Miguel, Correia; Bessani, Alysson

    2014-01-01

    This is report contains the formal proofs for the techniques for increasing the consistency of cloud storage as presented in "Bessani et al. SCFS: A Cloud-backed File System. Proc. of the 2014 USENIX Annual Technical Conference. June 2014." The consistency anchor technique allows one to increase the consistency provided by eventually consistent cloud storage services like Amazon S3. This technique has been used in the SCFS (Shared Cloud File System) cloud-backed file system for solving rea...

  19. Collecting Solar Energy. Solar Energy Education Project.

    Science.gov (United States)

    O'Brien, Alexander

    This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

  20. Influence of solvents on properties of solar selective coatings

    Indian Academy of Sciences (India)

    Solar selective coatings for solar thermal flat-plate collectors consisting of crystalline copper oxides and amorphous nickel oxide composites were obtained by robotic spray pyrolyzed deposition. The parameters were optimized for increased spectral selectivity (): high solar absorptance and low thermal emittance.

  1. Flexible thermal cycle test equipment for concentrator solar cells

    Science.gov (United States)

    Hebert, Peter H [Glendale, CA; Brandt, Randolph J [Palmdale, CA

    2012-06-19

    A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

  2. Installation package for a sunspot cascade solar water heating system

    Science.gov (United States)

    1980-01-01

    Solar water heating systems installed at Tempe, Arizona and San Diego, California are described. The systems consist of the following: collector, collector-tank water loop, solar tank, conventional tank, and controls. General guidelines which may be utilized in development of detailed installation plans and specifications are provided along with instruction on operation, maintenance, and installation of solar hot water systems.

  3. Performance Evaluation of a Pebble Bed Solar Crop Dryer ...

    African Journals Online (AJOL)

    Nigerian Journal of Technology ... The solar crop dryer consists of an imbedded pebble bed solar heat storage unit/solar collector ... The crop-drying chamber is made of drying trays of wire gauze while the roof is made of transparent glazing.

  4. PbSe Nanocrystal Excitonic Solar Cells

    KAUST Repository

    Choi, Joshua J.; Lim, Yee-Fun; Santiago-Berrios, Mitk’ El B.; Oh, Matthew; Hyun, Byung-Ryool; Sun, Liangfeng; Bartnik, Adam C.; Goedhart, Augusta; Malliaras, George G.; Abruña, Héctor D.; Wise, Frank W.; Hanrath, Tobias

    2009-01-01

    that Is distinct from previously reported Schottky devices and consistent with signatures of excitonic solar cells. Remarkably, despite the limitation of planar junction structure, and without film thickness optimization, the best performing device shows a 1-sun

  5. Installation package for concentrating solar collector panels

    Science.gov (United States)

    1978-01-01

    The concentrating solar collector panels comprise a complete package array consisting of collector panels using modified Fresnel prismatic lenses for a 10 to 1 concentrating ratio, supporting framework, fluid manifolding and tracking drive system, and unassembled components for field erection.

  6. Solar Advisor Model User Guide for Version 2.0

    Energy Technology Data Exchange (ETDEWEB)

    Gilman, P.; Blair, N.; Mehos, M.; Christensen, C.; Janzou, S.; Cameron, C.

    2008-08-01

    The Solar Advisor Model (SAM) provides a consistent framework for analyzing and comparing power system costs and performance across the range of solar technologies and markets, from photovoltaic systems for residential and commercial markets to concentrating solar power and large photovoltaic systems for utility markets. This manual describes Version 2.0 of the software, which can model photovoltaic and concentrating solar power technologies for electric applications for several markets. The current version of the Solar Advisor Model does not model solar heating and lighting technologies.

  7. Solar energy in buildings: Implications for California energy policy

    Science.gov (United States)

    Hirshberg, A. S.; Davis, E. S.

    1977-01-01

    An assessment of the potential of active solar energy systems for buildings in California is summarized. The technology used for solar heating, cooling, and water heating in buildings is discussed. The major California weather zones and the solar energy designs are described, as well as the sizing of solar energy systems and their performance. The cost of solar energy systems is given both at current prices and at prices consistent with optimistic estimates for the cost of collectors. The main institutional barriers to the wide spread use of solar energy are summarized.

  8. Performance evaluation of the Solar Building Test Facility

    Science.gov (United States)

    Jensen, R. N.

    1981-01-01

    The general performance of the NASA Solar Building Test Facility (SBTF) and its subsystems and components over a four year operational period is discussed, and data are provided for a typical one year period. The facility consists of a 4645 sq office building modified to accept solar heated water for operation of an absorption air conditioner and a baseboard heating system. An adjoining 1176 sq solar flat plate collector field with a 114 cu tank provides the solar heated water. The solar system provided 57 percent of the energy required for heating and cooling on an annual basis. The average efficiency of the solar collectors was 26 percent over a one year period.

  9. Concentrated solar power generation using solar receivers

    Science.gov (United States)

    Anderson, Bruce N.; Treece, William Dean; Brown, Dan; Bennhold, Florian; Hilgert, Christoph

    2017-08-08

    Inventive concentrated solar power systems using solar receivers, and related devices and methods, are generally described. Low pressure solar receivers are provided that function to convert solar radiation energy to thermal energy of a working fluid, e.g., a working fluid of a power generation or thermal storage system. In some embodiments, low pressure solar receivers are provided herein that are useful in conjunction with gas turbine based power generation systems.

  10. Solar charge controller in solar street light

    OpenAIRE

    Dong, Haibo

    2014-01-01

    Recently, with the rapid development of scientific technology, the conventional energy cannot meet the requirement of human beings. People are looking for the utilization of renew energy. Solar en-ergy as a new clean energy has attract the eyes of people. The applications of solar energy are popular to human society. Solar street light is a good example. This thesis will focus on a deeper research of the popular and ubiquitous solar street light in China. However, solar charge controll...

  11. Solar Training Network and Solar Ready Vets

    Energy Technology Data Exchange (ETDEWEB)

    Dalstrom, Tenley Ann

    2016-09-14

    In 2016, the White House announced the Solar Ready Vets program, funded under DOE's SunShot initiative would be administered by The Solar Foundation to connect transitioning military personnel to solar training and employment as they separate from service. This presentation is geared to informing and recruiting employer partners for the Solar Ready Vets program, and the Solar Training Network. It describes the programs, and the benefits to employers that choose to connect to the programs.

  12. Solar club

    CERN Multimedia

    Solar club

    2013-01-01

    SOLAR CLUB Le  CERN-Solar-Club souhaite une  très bonne année 2013 à tous les Cernois et Cernoises, et remercie encore une fois  tous ceux et celles qui, fin octobre, par leur vote, nous ont permis de finir dans les 5 premiers du concours "Conforama Solidaire" et ainsi financer nôtre projet "énergie solaire et eau potable pour Kilela Balanda" en République Démocratique du Congo (voir : http://www.confo.ch/solidarite/?lang=fr). Nous vous annoncons également notre Assemblée Générale Annuelle jeudi 21 février à 18 h 00 Salle C, 1er étage, Bât. 61 Vous êtes les bienvenus si vous souhaitez en savoir un peu plus sur les énergies renouvelables.

  13. Fisica solare

    CERN Document Server

    Degl’Innocenti, Egidio Landi

    2008-01-01

    Il volume è un'introduzione alla Fisica Solare che si propone lo scopo di illustrare alla persona che intende avvicinarsi a questa disciplina (studenti, dottori di ricerca, ricercatori) i meccanismi fisici che stanno alla base della complessa fenomenologia osservata sulla stella a noi più vicina. Il volume non ha la pretesa di essere esauriente (basta pensare che la fisica solare spazia su un gran numero di discipline, quali la Fisica Nucleare, la Termodinamica, L'Elettrodinamica, la Fisica Atomica e Molecolare, la Spettoscopia in tutte le bande dello spettro elettromagnetico, la Magnetoidrodinamica, la Fisica del Plasma, lo sviluppo di nuova strumentazione, l'Ottica, ecc.). Piuttosto, sono stati scelti un numero di argomenti di rilevanza fondamentale nello studio presente del Sole (soprattutto nei riguardi delle osservazioni da terra con grandi telescopi) e su tali argomenti si è cercato di dare una panoramica generale, inclusiva dell'evoluzione storica, senza scendere in soverchi dettagli. Siccome la Fis...

  14. Solar reflector

    Energy Technology Data Exchange (ETDEWEB)

    Dvorak, J

    1983-01-15

    The reflector in the form of part of a cylindrical surface delimited by two envelopes is installed on a platform which can move on an inclined curvilinear path. The angle of inclination of the path depends on the latitude of the locality. The reflected rays are focused on the tubular absorber. One of the axes of the platform is linked to a brake controlled by a sensor for intensity of solar radiation. The sensor is a pipe filled with liquid with high value of the temperature expansion coefficient, for example alcohol. The pipe is insulated from one side and is accessible to the solar rays from the opposite. One end of the pipe is equipped with a bending end or piston. In order to expand the fluid in the sensor, the pipe acts on the brake, and the reflector is installed in a position corresponding to the maximum radiation intensity.

  15. Solar neutrinos and solar accretion of interstellar matter

    International Nuclear Information System (INIS)

    Newman, M.J.; Talbot, R.J. Jr.

    1976-01-01

    It is argued that if the Hoyle-Lyttleton mass accretion rate applies (Proc. Camb. Phil. Soc., Math. Phys. Sci. 35: 405 (1939)) the accretion of interstellar matter by the Sun is sufficient to enhance the surface heavy element abundances. This will also apply to other solar-type stars. The enhancement may be sufficient to allow the construction of consistent solar models with an interior heavy element abundance significantly lower than the observed surface abundance. This state of affairs lowers the predicted solar neutrino flux. It has been suggested that a similar enhancement of surface abundances might occur due to accretion of 'planetesimals' left over after formation of the solar system, and both processes may occur, thereby increasing the effect. The simple accretion model of Hoyle and Lyttleton is discussed mathematically. A crucial question to be answered by future research, however, is whether or not accretion on to the solar surface actually occurs. One of the most obvious obstacles is the outward flowing solar wind, and this is discussed. It appears that the outward flow can be reversed to an inward flow for certain interstellar cloud densities. (U.K.)

  16. Solar pulsations

    International Nuclear Information System (INIS)

    Zirker, J.B.

    1980-01-01

    Oscillations of the surface of the sun, with periods between 5 and 160 min, have been observed by several spectroscopic techniques, and preliminary interpretations have been offered. The 5-min oscillations are global, nonradial, acoustic standing waves in the subsurface zone. Internal differential rotation speeds have been deduced from the Doppler splitting of these waves. Oscillations with longer periods have been reported, but need confirmation. The longest periods offer a tool for investigating the solar interior

  17. Solar Chameleons

    CERN Document Server

    Brax, Philippe

    2010-01-01

    We analyse the creation of chameleons deep inside the sun and their subsequent conversion to photons near the magnetised surface of the sun. We find that the spectrum of the regenerated photons lies in the soft X-ray region, hence addressing the solar corona problem. Moreover, these back-converted photons originating from chameleons have an intrinsic difference with regenerated photons from axions: their relative polarisations are mutually orthogonal before Compton interacting with the surrounding plasma. Depending on the photon-chameleon coupling and working in the strong coupling regime of the chameleons to matter, we find that the induced photon flux, when regenerated resonantly with the surrounding plasma, coincides with the solar flux within the soft X-ray energy range. Moreover, using the soft X-ray solar flux as a prior, we find that with a strong enough photon-chameleon coupling the chameleons emitted by the sun could lead to a regenerated photon flux in the CAST pipes, which could be within the reach...

  18. Solar chameleons

    International Nuclear Information System (INIS)

    Brax, Philippe; Zioutas, Konstantin

    2010-01-01

    We analyze the creation of chameleons deep inside the Sun (R∼0.7R sun ) and their subsequent conversion to photons near the magnetized surface of the Sun. We find that the spectrum of the regenerated photons lies in the soft x-ray region, hence addressing the solar corona problem. Moreover, these back-converted photons originating from chameleons have an intrinsic difference with regenerated photons from axions: their relative polarizations are mutually orthogonal before Compton interacting with the surrounding plasma. Depending on the photon-chameleon coupling and working in the strong coupling regime of the chameleons to matter, we find that the induced photon flux, when regenerated resonantly with the surrounding plasma, coincides with the solar flux within the soft x-ray energy range. Moreover, using the soft x-ray solar flux as a prior, we find that with a strong enough photon-chameleon coupling, the chameleons emitted by the Sun could lead to a regenerated photon flux in the CAST magnetic pipes, which could be within the reach of CAST with upgraded detector performance. Then, axion helioscopes have thus the potential to detect and identify particle candidates for the ubiquitous dark energy in the Universe.

  19. Solar flares

    International Nuclear Information System (INIS)

    Kaastra, J.S.

    1985-01-01

    In this thesis an electrodynamic model for solar flares is developed. The main theoretical achievements underlying the present study are treated briefly and the observable flare parameters are described within the framework of the flare model of this thesis. The flare model predicts large induced electric fields. Therefore, acceleration processes of charged particles by direct electric fields are treated. The spectrum of the accelerated particles in strong electric fields is calculated, 3 with the electric field and the magnetic field perpendicular and in the vicinity of an X-type magnetic neutral line. An electromagnetic field configuration arises in the case of a solar flare. A rising current filament in a quiescent background bipolar magnetic field causes naturally an X-type magnetic field configuration below the filament with a strong induced electric field perpendicular to the ambient magnetic field. This field configuration drives particles and magnetic energy towards the neutral line, where a current sheet is generated. The global evolution of the fields in the flare is determined by force balance of the Lorentz forces on the filament and the force balance on the current sheet. The X-ray, optical and radio observations of a large solar flare on May 16, 1981 are analyzed. It is found that these data fit the model very well. (Auth.)

  20. Solar cities

    International Nuclear Information System (INIS)

    Roaf, S.; Fuentes, M.; Gupta, R.

    2005-01-01

    Over the last decade, climate change has moved from being the concern of few to a widely recognized threat to humanity itself and the natural environment. The 1990s were the warmest decade on record, and ever-increasing atmospheric levels of greenhouse gases such as carbon dioxide (CO/sub 2/), could, if left unchecked lead to serious consequences globally, including increased risks of droughts, floods and storms, disruption to agriculture, rising sea levels and the spread of disease. The contribution of anthropogenic emissions of carbon dioxide has been recognized as the principal cause of the atmospheric changes that drive these climate trends. Globally, buildings are the largest source of indirect carbon emissions. In 2000, the UK Royal Commission on Environmental Pollution estimated that in order to stabilise carbon emissions at levels, which avoid catastrophic alterations in the climate, we would have to reduce emissions from the built environment by at least 60% by 2050 and 80% by 2100 relative to 1997 levels. Studies of the Oxford Ecohouse have demonstrated that it is not difficult to reduce carbon emissions from houses by 60% or more through energy efficiency measures, but it is only possible to reach the 90% level of reductions required by using renewable energy technologies. Solar energy technologies have been the most successfully applied of all renewable to date largely because they are the only systems that can be incorporated easily into the urban fabric. In addition, the short fossil fuel horizons that are predicted (c. 40 years left for oil and 65 years for gas) will drive the markets for solar technologies. For these reasons, the cities of the future will be powered by solar energy, to a greater or lesser extent, depending on the city form and location. In recognition of the need to move rapidly towards a renewable energy future, a group of international cities, including Oxford, have started the Solar City Network. In this paper we outline the

  1. Early solar physics

    CERN Document Server

    Meadows, A J

    1970-01-01

    Early Solar Physics reviews developments in solar physics, particularly the advent of solar spectroscopy and the discovery of relationships between the various layers of the solar atmosphere and between the different forms of solar activity. Topics covered include solar observations during 1843; chemical analysis of the solar atmosphere; the spectrum of a solar prominence; and the solar eclipse of December 12, 1871. Spectroscopic observations of the sun are also presented. This book is comprised of 30 chapters and begins with an overview of ideas about the sun in the mid-nineteenth century, fo

  2. The solar dynamo

    International Nuclear Information System (INIS)

    Brandenburg, A.; Helsinki Univ.; Tuominen, I.

    1991-01-01

    The traditional αΩ-dynamo as a model for the solar cycle has been successful in explaining the butterfly diagram, phase relations between poloidal and toroidal field, and polar branch migration features. Observational and theoretical achievements in recent years have however shaken this picture. The current trend is towards dynamos operating in the overshoot region of the convection zone. Nevertheless, there are many open questions and a consistent picture has not been established. In this paper we compare recent approaches and discuss remaining problems. (orig.)

  3. Low cost thermal solar collector

    International Nuclear Information System (INIS)

    Abugderah, M. M.; Schneider, E. L.; Tontini, M. V.

    2006-01-01

    Solar energy is a good alternative in the economy of the electric energy mainly for the water heating. However, the solar heaters used demand a high initial investment, becoming the warm water from solar energy inaccessible to a large part of the society. Thus, a low cost solar heater was developed, constructed and tested in the chemical engineering department of West Parana State University-Unioeste. This equipment consists of 300 cans, divided in 30 columns of 10 cans each, all painted in black to enhance the obsorption of the solar radiation. The columns are connected to a pipe of pvc of 8 liters with 0.085m of external diameter. The equipment is capable to heat 120 liters of water in temperatures around 60 degree centigrade. The heater is insolated in its inferior part with cardboard and aluminum, covered with a transparent plastic in its superior. The system still counts with a insulated thermal reservoir, which can conserve the water in temperatures adjusted for the night non-solar days domestic use. The advantage of the constructed is it low cost material. The results are given an graphical tabular from showing acceptable efficiencies.(Autho

  4. Solar solution

    International Nuclear Information System (INIS)

    Shi Zhengrong

    2009-01-01

    China is facing enormous energy challenges. Everyone seems to know that we need to increase our energy supply by the equivalent of one power plant per week to support China's economic growth, which is allowing millions of people to enjoy better standards of living. Much less is known of the extent to which China has taken steps to mitigate the impact of that growing energy demand through incentives for greater efficiency and renewable energy. Policies include: Cutting energy intensity - 20 per cent between 2005 and 2010, saving five times as much CO 2 as the EU's goals. Cutting major pollutants by 10 per cent by 2010. Setting one of the world's most aggressive renewable energy standards: 15 per cent of national energy from renewables by 2020. Setting targets of 300 megawatts of installed solar by 2010, and 1.8 gigawatts by 2020, in the 2007 National Development and Reform Commission Renewable Energy Development Plan. Dedicating $180 billion for renewable energy by 2020. Imposing energy efficiency targets for the top 1,000 companies, a measure with greater carbon savings potential than most Western initiatives. Establishing building energy codes in all regions and extensive efficiency standards for appliances, which will be particularly important as China continues to grow. Targeting new buildings in major cities like Beijing, Shanghai and Chongqing, to achieve 65 per cent greater energy efficiency than local codes require. Closing thousands of older, smaller, dirtier power plants by 2010. China understands the economic development potential in clean energy technologies. Even the noted journalist Thomas Friedman has remarked that 'China is going green in a big way,' using domestic demand for cleaner energy to build low-cost, scalable green technologies. Suntech Power Holdings - now the world's largest solar photovoltaic (PV) module manufacturer, with operations around the globe - was just one of dozens of solar companies that realised the opportunity provided by

  5. Solar energy collector

    Science.gov (United States)

    Brin, Raymond L.; Pace, Thomas L.

    1978-01-01

    The invention relates to a solar energy collector comprising solar energy absorbing material within chamber having a transparent wall, solar energy being transmitted through the transparent wall, and efficiently absorbed by the absorbing material, for transfer to a heat transfer fluid. The solar energy absorbing material, of generally foraminous nature, absorbs and transmits the solar energy with improved efficiency.

  6. Solar Pumping : The Basics

    OpenAIRE

    World Bank Group

    2018-01-01

    Solar photovoltaic water pumping (SWP) uses energy from solar photovoltaic (PV) panels to power an electric water pump. The entire process, from sunlight to stored energy, is elegant and simple. Over last seven years, the technology and price of solar pumping have evolved dramatically and hence the opportunities it presents. Solar pumping is most competitive in regions with high solar inso...

  7. A new approach to hull consistency

    Directory of Open Access Journals (Sweden)

    Kolev Lubomir

    2016-06-01

    Full Text Available Hull consistency is a known technique to improve the efficiency of iterative interval methods for solving nonlinear systems describing steady-states in various circuits. Presently, hull consistency is checked in a scalar manner, i.e. successively for each equation of the nonlinear system with respect to a single variable. In the present poster, a new more general approach to implementing hull consistency is suggested which consists in treating simultaneously several equations with respect to the same number of variables.

  8. Replica consistency in a Data Grid

    International Nuclear Information System (INIS)

    Domenici, Andrea; Donno, Flavia; Pucciani, Gianni; Stockinger, Heinz; Stockinger, Kurt

    2004-01-01

    A Data Grid is a wide area computing infrastructure that employs Grid technologies to provide storage capacity and processing power to applications that handle very large quantities of data. Data Grids rely on data replication to achieve better performance and reliability by storing copies of data sets on different Grid nodes. When a data set can be modified by applications, the problem of maintaining consistency among existing copies arises. The consistency problem also concerns metadata, i.e., additional information about application data sets such as indices, directories, or catalogues. This kind of metadata is used both by the applications and by the Grid middleware to manage the data. For instance, the Replica Management Service (the Grid middleware component that controls data replication) uses catalogues to find the replicas of each data set. Such catalogues can also be replicated and their consistency is crucial to the correct operation of the Grid. Therefore, metadata consistency generally poses stricter requirements than data consistency. In this paper we report on the development of a Replica Consistency Service based on the middleware mainly developed by the European Data Grid Project. The paper summarises the main issues in the replica consistency problem, and lays out a high-level architectural design for a Replica Consistency Service. Finally, results from simulations of different consistency models are presented

  9. Solar constant values for estimating solar radiation

    International Nuclear Information System (INIS)

    Li, Huashan; Lian, Yongwang; Wang, Xianlong; Ma, Weibin; Zhao, Liang

    2011-01-01

    There are many solar constant values given and adopted by researchers, leading to confusion in estimating solar radiation. In this study, some solar constant values collected from literature for estimating solar radiation with the Angstroem-Prescott correlation are tested in China using the measured data between 1971 and 2000. According to the ranking method based on the t-statistic, a strategy to select the best solar constant value for estimating the monthly average daily global solar radiation with the Angstroem-Prescott correlation is proposed. -- Research highlights: → The effect of the solar constant on estimating solar radiation is investigated. → The investigation covers a diverse range of climate and geography in China. → A strategy to select the best solar constant for estimating radiation is proposed.

  10. Detecting photovoltaic solar panels using hyperspectral imagery and estimating solar power production

    Science.gov (United States)

    Czirjak, Daniel

    2017-04-01

    Remote sensing platforms have consistently demonstrated the ability to detect, and in some cases identify, specific targets of interest, and photovoltaic solar panels are shown to have a unique spectral signature that is consistent across multiple manufacturers and construction methods. Solar panels are proven to be detectable in hyperspectral imagery using common statistical target detection methods such as the adaptive cosine estimator, and false alarms can be mitigated through the use of a spectral verification process that eliminates pixels that do not have the key spectral features of photovoltaic solar panel reflectance spectrum. The normalized solar panel index is described and is a key component in the false-alarm mitigation process. After spectral verification, these solar panel arrays are confirmed on openly available literal imagery and can be measured using numerous open-source algorithms and tools. The measurements allow for the assessment of overall solar power generation capacity using an equation that accounts for solar insolation, the area of solar panels, and the efficiency of the solar panels conversion of solar energy to power. Using a known location with readily available information, the methods outlined in this paper estimate the power generation capabilities within 6% of the rated power.

  11. Solar Technology Center

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Bob

    2011-04-27

    The Department of Energy, Golden Field Office, awarded a grant to the UNLV Research Foundation (UNLVRF) on August 1, 2005 to develop a solar and renewable energy information center. The Solar Technology Center (STC) is to be developed in two phases, with Phase I consisting of all activities necessary to determine feasibility of the project, including design and engineering, identification of land access issues and permitting necessary to determine project viability without permanently disturbing the project site, and completion of a National Environmental Policy Act (NEPA) Environmental Assessment. Phase II is the installation of infrastructure and related structures, which leads to commencement of operations of the STC. The STC is located in the Boulder City designated 3,000-acre Eldorado Valley Energy Zone, approximately 15 miles southwest of downtown Boulder City and fronting on Eldorado Valley Drive. The 33-acre vacant parcel has been leased to the Nevada Test Site Development Corporation (NTSDC) by Boulder City to accommodate a planned facility that will be synergistic with present and planned energy projects in the Zone. The parcel will be developed by the UNLVRF. The NTSDC is the economic development arm of the UNLVRF. UNLVRF will be the entity responsible for overseeing the lease and the development project to assure compliance with the lease stipulations established by Boulder City. The STC will be operated and maintained by University of Nevada, Las Vegas (UNLV) and its Center for Energy Research (UNLV-CER). Land parcels in the Eldorado Valley Energy Zone near the 33-acre lease are committed to the construction and operation of an electrical grid connected solar energy production facility. Other projects supporting renewable and solar technologies have been developed within the energy zone, with several more developments in the horizon.

  12. Student Effort, Consistency, and Online Performance

    Science.gov (United States)

    Patron, Hilde; Lopez, Salvador

    2011-01-01

    This paper examines how student effort, consistency, motivation, and marginal learning, influence student grades in an online course. We use data from eleven Microeconomics courses taught online for a total of 212 students. Our findings show that consistency, or less time variation, is a statistically significant explanatory variable, whereas…

  13. Translationally invariant self-consistent field theories

    International Nuclear Information System (INIS)

    Shakin, C.M.; Weiss, M.S.

    1977-01-01

    We present a self-consistent field theory which is translationally invariant. The equations obtained go over to the usual Hartree-Fock equations in the limit of large particle number. In addition to deriving the dynamic equations for the self-consistent amplitudes we discuss the calculation of form factors and various other observables

  14. Sticky continuous processes have consistent price systems

    DEFF Research Database (Denmark)

    Bender, Christian; Pakkanen, Mikko; Sayit, Hasanjan

    Under proportional transaction costs, a price process is said to have a consistent price system, if there is a semimartingale with an equivalent martingale measure that evolves within the bid-ask spread. We show that a continuous, multi-asset price process has a consistent price system, under...

  15. Consistent-handed individuals are more authoritarian.

    Science.gov (United States)

    Lyle, Keith B; Grillo, Michael C

    2014-01-01

    Individuals differ in the consistency with which they use one hand over the other to perform everyday activities. Some individuals are very consistent, habitually using a single hand to perform most tasks. Others are relatively inconsistent, and hence make greater use of both hands. More- versus less-consistent individuals have been shown to differ in numerous aspects of personality and cognition. In several respects consistent-handed individuals resemble authoritarian individuals. For example, both consistent-handedness and authoritarianism have been linked to cognitive inflexibility. Therefore we hypothesised that consistent-handedness is an external marker for authoritarianism. Confirming our hypothesis, we found that consistent-handers scored higher than inconsistent-handers on a measure of submission to authority, were more likely to identify with a conservative political party (Republican), and expressed less-positive attitudes towards out-groups. We propose that authoritarianism may be influenced by the degree of interaction between the left and right brain hemispheres, which has been found to differ between consistent- and inconsistent-handed individuals.

  16. Testing the visual consistency of web sites

    NARCIS (Netherlands)

    van der Geest, Thea; Loorbach, N.R.

    2005-01-01

    Consistency in the visual appearance of Web pages is often checked by experts, such as designers or reviewers. This article reports a card sort study conducted to determine whether users rather than experts could distinguish visual (in-)consistency in Web elements and pages. The users proved to

  17. Consistent spectroscopy for a extended gauge model

    International Nuclear Information System (INIS)

    Oliveira Neto, G. de.

    1990-11-01

    The consistent spectroscopy was obtained with a Lagrangian constructed with vector fields with a U(1) group extended symmetry. As consistent spectroscopy is understood the determination of quantum physical properties described by the model in an manner independent from the possible parametrizations adopted in their description. (L.C.J.A.)

  18. Modeling and Testing Legacy Data Consistency Requirements

    DEFF Research Database (Denmark)

    Nytun, J. P.; Jensen, Christian Søndergaard

    2003-01-01

    An increasing number of data sources are available on the Internet, many of which offer semantically overlapping data, but based on different schemas, or models. While it is often of interest to integrate such data sources, the lack of consistency among them makes this integration difficult....... This paper addresses the need for new techniques that enable the modeling and consistency checking for legacy data sources. Specifically, the paper contributes to the development of a framework that enables consistency testing of data coming from different types of data sources. The vehicle is UML and its...... accompanying XMI. The paper presents techniques for modeling consistency requirements using OCL and other UML modeling elements: it studies how models that describe the required consistencies among instances of legacy models can be designed in standard UML tools that support XMI. The paper also considers...

  19. Solar neutrino

    Energy Technology Data Exchange (ETDEWEB)

    Sugimoto, D [Tokyo Univ. (Japan). Coll. of General Education

    1975-01-01

    The measurement of solar neutrino was performed by using the reaction /sup 37/cl+..nu..sub(e)..-->../sup 37/Ar+e/sup -/ by Davis et al. The argon gas produced through the above mentioned reaction in a tank containing 610 ton of C/sub 2/Cl/sub 4/ was collected and measured. The rate of production of /sup 37/Ar was 0.13+-0.20/day, and the net production rate by the solar neutrino was 0.06+-0.20/day, being corrected for background. This value corresponds to 0.5+-1.0 SNU. Theoretical calculation with the model of spherically symmetric solar development gave an expected value of 5.6 SNU, which is in contradiction with the experimental value. Reason of this discrepancy was considered. The possibility of decay of neutrino to the other particles with weak interaction is very slight. Various models of the sun were investigated, but the results were still inconsistent with the experiment. The mixing of matters in the sun may cause the reduction of neutrino. If He gas comes to the center of the sun by mixing, the reaction, /sup 3/He+/sup 3/He, progresses excessively at the center, and it produces the expansion of the core of the sun. Then, the temperature drops and the neutrino is reduced. Various models which can explain the neutrino of less than ISNU have been presented. However, other theory says that the reduction of neutrino is not expected even if the mixing is considered. A problem concerning the mixing is whether the thermal instability which causes the mixing exists. (Kato, T.).

  20. Long-Period Solar Variability

    Energy Technology Data Exchange (ETDEWEB)

    GAUTHIER,JOHN H.

    2000-07-20

    Terrestrial climate records and historical observations of the Sun suggest that the Sun undergoes aperiodic oscillations in radiative output and size over time periods of centuries and millenia. Such behavior can be explained by the solar convective zone acting as a nonlinear oscillator, forced at the sunspot-cycle frequency by variations in heliomagnetic field strength. A forced variant of the Lorenz equations can generate a time series with the same characteristics as the solar and climate records. The timescales and magnitudes of oscillations that could be caused by this mechanism are consistent with what is known about the Sun and terrestrial climate.

  1. Self-consistent modeling of amorphous silicon devices

    International Nuclear Information System (INIS)

    Hack, M.

    1987-01-01

    The authors developed a computer model to describe the steady-state behaviour of a range of amorphous silicon devices. It is based on the complete set of transport equations and takes into account the important role played by the continuous distribution of localized states in the mobility gap of amorphous silicon. Using one set of parameters they have been able to self-consistently simulate the current-voltage characteristics of p-i-n (or n-i-p) solar cells under illumination, the dark behaviour of field-effect transistors, p-i-n diodes and n-i-n diodes in both the ohmic and space charge limited regimes. This model also describes the steady-state photoconductivity of amorphous silicon, in particular, its dependence on temperature, doping and illumination intensity

  2. Solar Energy Systems

    Science.gov (United States)

    1984-01-01

    Calibrated in kilowatt hours per square meter, the solar counter produced by Dodge Products, Inc. provides a numerical count of the solar energy that has accumulated on a surface. Solar energy sensing, measuring and recording devices in corporate solar cell technology developed by Lewis Research Center. Customers for their various devices include architects, engineers and others engaged in construction and operation of solar energy facilities; manufacturers of solar systems or solar related products, such as glare reducing windows; and solar energy planners in federal and state government agencies.

  3. Mobile Solar Tracker Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NIST's mobile solar tracking facility is used to characterize the electrical performance of photovoltaic panels. It incorporates meteorological instruments, a solar...

  4. Solar Club

    CERN Multimedia

    Solar Club

    2010-01-01

    Le CERN Solar-Club vous invite à la présentation de sa participation dans : The Cyprus Institute Solar Car Challenge du 18 au 20 juin à Chypre . en réponse à l’invitation dudit institut, dans le cadre de la demande de Chypre pour joindre le CERN . Le Club y participera avec son vénérable Photon rénové , et la Dyane E-Solaire d’un de ses membres, rénové aussi . Après la présentation, le forum est ouvert pour toutes vos questions et propositions diverses, également dans d’autres domaines des énergies renouvelables . C’est aussi l’occasion pour joindre le Club ! Où, et Quand ? Le Mercredi 7 Avril à 19 h 00, au 6ème étage du Bât. Principal, (60-6-015) à la suite de l’AG des membres du Club , à 18h00 dans...

  5. Solar UV Variations During the Decline of Cycle 23

    Science.gov (United States)

    DeLand, Matthew, T.; Cebula, Richard P.

    2011-01-01

    Characterization of temporal and spectral variations in solar ultraviolet irradiance over a solar cycle is essential for understanding the forcing of Earth's atmosphere and climate. Satellite measurements of solar UV variability for solar cycles 21, 22, and 23 show consistent solar cycle irradiance changes at key wavelengths (e.g. 205 nm, 250 nm) within instrumental uncertainties. All historical data sets also show the same relative spectral dependence for both short-term (rotational) and long-term (solar cycle) variations. Empirical solar irradiance models also produce long-term solar UV variations that agree well with observational data. Recent UV irradiance data from the Solar Radiation and Climate Experiment (SORCE) Spectral Irradiance Monitor (SIM) and Solar Stellar Irradiance Comparison Experiment (SOLSTICE) instruments covering the declining phase of Cycle 23 present a different picture oflong-term solar variations from previous results. Time series of SIM and SOLSTICE spectral irradiance data between 2003 and 2007 show solar variations that greatly exceed both previous measurements and predicted irradiance changes over this period, and the spectral dependence of the SIM and SOLSTICE variations during these years do not show features expected from solar physics theory. The use of SORCE irradiance variations in atmospheric models yields substantially different middle atmosphere ozone responses in both magnitude and vertical structure. However, short-term solar variability derived from SIM and SOLSTICE UV irradiance data is consistent with concurrent solar UV measurements from other instruments, as well as previous results, suggesting no change in solar physics. Our analysis of short-term solar variability is much less sensitive to residual instrument response changes than the observations of long-term variations. The SORCE long-term UV results can be explained by under-correction of instrument response changes during the first few years of measurements

  6. Consistency in the World Wide Web

    DEFF Research Database (Denmark)

    Thomsen, Jakob Grauenkjær

    Tim Berners-Lee envisioned that computers will behave as agents of humans on the World Wide Web, where they will retrieve, extract, and interact with information from the World Wide Web. A step towards this vision is to make computers capable of extracting this information in a reliable...... and consistent way. In this dissertation we study steps towards this vision by showing techniques for the specication, the verication and the evaluation of the consistency of information in the World Wide Web. We show how to detect certain classes of errors in a specication of information, and we show how...... the World Wide Web, in order to help perform consistent evaluations of web extraction techniques. These contributions are steps towards having computers reliable and consistently extract information from the World Wide Web, which in turn are steps towards achieving Tim Berners-Lee's vision. ii...

  7. Consistent histories and operational quantum theory

    International Nuclear Information System (INIS)

    Rudolph, O.

    1996-01-01

    In this work a generalization of the consistent histories approach to quantum mechanics is presented. We first critically review the consistent histories approach to nonrelativistic quantum mechanics in a mathematically rigorous way and give some general comments about it. We investigate to what extent the consistent histories scheme is compatible with the results of the operational formulation of quantum mechanics. According to the operational approach, nonrelativistic quantum mechanics is most generally formulated in terms of effects, states, and operations. We formulate a generalized consistent histories theory using the concepts and the terminology which have proven useful in the operational formulation of quantum mechanics. The logical rule of the logical interpretation of quantum mechanics is generalized to the present context. The algebraic structure of the generalized theory is studied in detail

  8. Self-consistent areas law in QCD

    International Nuclear Information System (INIS)

    Makeenko, Yu.M.; Migdal, A.A.

    1980-01-01

    The problem of obtaining the self-consistent areas law in quantum chromodynamics (QCD) is considered from the point of view of the quark confinement. The exact equation for the loop average in multicolor QCD is reduced to a bootstrap form. Its iterations yield new manifestly gauge invariant perturbation theory in the loop space, reproducing asymptotic freedom. For large loops, the areas law apprears to be a self-consistent solution

  9. Consistency of the MLE under mixture models

    OpenAIRE

    Chen, Jiahua

    2016-01-01

    The large-sample properties of likelihood-based statistical inference under mixture models have received much attention from statisticians. Although the consistency of the nonparametric MLE is regarded as a standard conclusion, many researchers ignore the precise conditions required on the mixture model. An incorrect claim of consistency can lead to false conclusions even if the mixture model under investigation seems well behaved. Under a finite normal mixture model, for instance, the consis...

  10. Solar thermophotovoltaic system using nanostructures.

    Science.gov (United States)

    Ungaro, Craig; Gray, Stephen K; Gupta, Mool C

    2015-09-21

    This paper presents results on a highly efficient experimental solar thermophotovoltaic (STPV) system using simulated solar energy. An overall power conversion efficiency of 6.2% was recorded under solar simulation. This was matched with a thermodynamic model, and the losses within the system, as well as a path forward to mitigate these losses, have been investigated. The system consists of a planar, tungsten absorbing/emitting structure with an anti-reflection layer coated laser-microtextured absorbing surface and single-layer dielectric coated emitting surface. A GaSb PV cell was used to capture the emitted radiation and convert it into electrical energy. This simple structure is both easy to fabricate and temperature stable, and contains no moving parts or heat exchange fluids.

  11. Solar cell power source system

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yoichi; Toma, Kunio; Fukuwa, Shinji

    1988-05-14

    This invention aims to supply a power source system with stable power output by reducing the power loss due to switching in the voltage stabilization even when the power source is a solar cell with frequent voltage variation. For this purpose, in a solar cell power source system consisting of a solar cell, a storage battery, a switching regulator placed between the storage cell and the load, and a load, arrangement was made that, by judging the input voltage from the storage battery, switch-acting the transistor of the switching regulator, if the input voltage is higher than the specified voltage; is the input voltage is lower than the specified voltage, the transistor is put in a full-on state. By this, the supply voltage can be stabilized even when the voltage fluctuates, and system gets more efficient as the switching loss decreases in the voltage stabilizing means. (1 fig)

  12. Solar Innovation Infographic | Solar Research | NREL

    Science.gov (United States)

    Innovation Infographic Solar Innovation Infographic Scientists have been working to harness power from the sun for about 200 years. Over the past 40 years, solar energy technologies have made research developments and industry milestones that helped shape our U.S. solar industry. Infographic Embed

  13. Midscale Commercial Solar Market | Solar Research | NREL

    Science.gov (United States)

    States To help prospective solar customers understand and use the policies of their state for midsized Customers, which equips prospective solar customers with the tools necessary to understand and use the solar corporate customers (Alabama Power's Renewable Procurement Program), and a company with approval to sell

  14. Solar neutrinos and nonradial solar oscillations

    International Nuclear Information System (INIS)

    Zatsepin, G.T.; Gavryuseva, E.A.; Kopysov, Yu.S.

    1980-01-01

    The problem of origin of surface solar oscillations is considered. It is assumed that generation of oscillations is performed by the solar nucleus. The necessary excitation condition for gravitational oscillations of the solar nucleus is a sharp decrease of the oscillation amplitude outside the nucleus, where the nuclear reaction rates are small and only radiation losses are considerable. It is shown that the specific singularities of gravitational wave propagation in solar entrails permit to attain a significant reduction of the oscillation amplitude. The solar entrails can serve as an effective trap for gravitational waves, if the substance of the solar nucleus is close to the state of convectional equilibrium. In order that the g 1 quadrupole mode of the solar nucleus has a period of 2h 40 min and sharply decreases in the solar mantle, it is enough that only the external part of the solar nucleus is close to the state of convectional equilibrium. Closeness of the solar nucleus to the state of convectional equilibrium is an argument in favour of its periodic mixing. Periodic mixing of the solar nucleus can serve as a cause of a low counting rate of solar neutrinos in R.Davis chlorous detector

  15. Solar energy an introduction

    CERN Document Server

    Mackay, Michael E

    2015-01-01

    Solar Energy presents an introduction to all aspects of solar energy, from photovoltaic devices to active and passive solar thermal energy conversion, giving both a detailed and broad perspective of the field. It is aimed at the beginner involved in solar energy or a related field, or for someone wanting to gain a broader perspective of solar energy technologies. A chapter considering solar radiation, basic principles applied to solar energy, semiconductor physics, and light absorption brings the reader on equal footing with the technology of either solar generated electrical current or useful heat. Details of how a solar cell works and then production of current from a photovoltaic device is discussed. Characterization of a solar cell is examined, allowing one the ability to interpret the current-voltage relation, followed by discussion of parameter extraction from this relation. This information can be used to understand what limits the performance of a given solar cell with the potential to optimize its pe...

  16. Measurements of chromospheric velocity fields by means of the Coimbra University spectroheliograph

    Czech Academy of Sciences Publication Activity Database

    Garcia, A.; Klvaňa, Miroslav; Sobotka, Michal

    2010-01-01

    Roč. 34, č. 1 (2010), s. 47-56 ISSN 1845-8319 R&D Projects: GA AV ČR IAA300030808 Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun * chromosphere * instrumentation Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  17. Self-consistent asset pricing models

    Science.gov (United States)

    Malevergne, Y.; Sornette, D.

    2007-08-01

    We discuss the foundations of factor or regression models in the light of the self-consistency condition that the market portfolio (and more generally the risk factors) is (are) constituted of the assets whose returns it is (they are) supposed to explain. As already reported in several articles, self-consistency implies correlations between the return disturbances. As a consequence, the alphas and betas of the factor model are unobservable. Self-consistency leads to renormalized betas with zero effective alphas, which are observable with standard OLS regressions. When the conditions derived from internal consistency are not met, the model is necessarily incomplete, which means that some sources of risk cannot be replicated (or hedged) by a portfolio of stocks traded on the market, even for infinite economies. Analytical derivations and numerical simulations show that, for arbitrary choices of the proxy which are different from the true market portfolio, a modified linear regression holds with a non-zero value αi at the origin between an asset i's return and the proxy's return. Self-consistency also introduces “orthogonality” and “normality” conditions linking the betas, alphas (as well as the residuals) and the weights of the proxy portfolio. Two diagnostics based on these orthogonality and normality conditions are implemented on a basket of 323 assets which have been components of the S&P500 in the period from January 1990 to February 2005. These two diagnostics show interesting departures from dynamical self-consistency starting about 2 years before the end of the Internet bubble. Assuming that the CAPM holds with the self-consistency condition, the OLS method automatically obeys the resulting orthogonality and normality conditions and therefore provides a simple way to self-consistently assess the parameters of the model by using proxy portfolios made only of the assets which are used in the CAPM regressions. Finally, the factor decomposition with the

  18. EDITORIAL Solar harvest Solar harvest

    Science.gov (United States)

    Demming, Anna

    2010-12-01

    The first observations of the photoelectric effect date back to the early 19th century from work by Alexandre Edmond Becquerel, Heinrich Hertz, Wilhelm Hallwachs and J J Thomson. The theory behind the phenomena was clarified in a seminal paper by Einstein in 1905 and became an archetypical feature of the wave-particle description of light. A different manifestation of quantised electron excitation, whereby electrons are not emitted but excited into the valence band of the material, is what we call the photoconductive effect. As well as providing an extension to theories in fundamental physics, the phenomenon has spawned a field with enormous ramifications in the energy industry through the development of solar cells. Among advances in photovoltaic technology has been the development of organic photovoltaic technology. These devices have many benefits over their inorganic counterparts, such as light-weight, flexible material properties, as well as versatile materials' synthesis and low-cost large-scale production—all highly advantageous for manufacturing. The first organic photovoltaic systems were reported over 50 years ago [1], but the potential of the field has escalated in recent years in terms of efficiency, largely through band offsetting. Since then, great progress has been made in studies for optimising the efficiency of organic solar cells, such as the work by researchers in Germany and the Netherlands, where investigations were made into the percentage composition and annealing effects on composites of poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) [2]. Hybrid devices that aim to exploit the advantages of both inorganic and organic constituents have also proven promising. One example of this is the work reported by researchers in Tunisia and France on a systematic study for optimising the composition morphology of TiO2 nanoparticles in poly(N-vinylcarbazole) (PVK), which also led to insights

  19. Introduction to solar radio astronomy and radio physics

    International Nuclear Information System (INIS)

    Krueger, A.

    1979-01-01

    A systematic summary is presented of the work done during the last thirty years in the field of solar radio astronomy from the standpoint of general solar physics. Instrumental aspects, observations and theory are covered. A brief introduction is given to the matter consisting of the history of solar radio astronomy and some fundamentals of astronomy and solar physics are outlined. Some topics of the instrumental background of solar radio astronomy and the main results of observations are presented. The elements of a theoretical interpretation of solar radio observations are reported and a synthesis of both observation and theory contributing to a general picture of solar and solar-terrestrial physics is outlined. (C.F./Auth)

  20. Solar flares

    International Nuclear Information System (INIS)

    Zirin, H.

    1974-01-01

    A review of the knowledge about solar flares which has been obtained through observations from the earth and from space by various methods is presented. High-resolution cinematography is best carried out at H-alpha wavelengths to reveal the structure, time history, and location of flares. The classification flares in H alpha according to either physical or morphological criteria is discussed. The study of flare morphology, which shows where, when, and how flares occur, is important for evaluating theories of flares. Consideration is given to studies of flares by optical spectroscopy, radio emissions, and at X-ray and XUV wavelengths. Research has shown where and possibly why flares occur, but the physics of the instability involved, of the particle acceleration, and of the heating are still not understood. (IAA)

  1. Automatic detection of solar features in HSOS full-disk solar images using guided filter

    Science.gov (United States)

    Yuan, Fei; Lin, Jiaben; Guo, Jingjing; Wang, Gang; Tong, Liyue; Zhang, Xinwei; Wang, Bingxiang

    2018-02-01

    A procedure is introduced for the automatic detection of solar features using full-disk solar images from Huairou Solar Observing Station (HSOS), National Astronomical Observatories of China. In image preprocessing, median filter is applied to remove the noises. Guided filter is adopted to enhance the edges of solar features and restrain the solar limb darkening, which is first introduced into the astronomical target detection. Then specific features are detected by Otsu algorithm and further threshold processing technique. Compared with other automatic detection procedures, our procedure has some advantages such as real time and reliability as well as no need of local threshold. Also, it reduces the amount of computation largely, which is benefited from the efficient guided filter algorithm. The procedure has been tested on one month sequences (December 2013) of HSOS full-disk solar images and the result shows that the number of features detected by our procedure is well consistent with the manual one.

  2. Solar Decathlon 2015 - Indigo Pine

    Energy Technology Data Exchange (ETDEWEB)

    Blouin, Vincent [Clemson Univ., SC (United States)

    2016-05-30

    The Solar Decathlon competition challenges students across the country to design and build a net-zero, market ready solar powered home. The bi-annual competition consists of ten contests that seek to balance the home on a scale of innovation. The ten contests were selected by to organizers to address all aspects of housing, including architecture, market appeal, engineering, communication, affordability, comfort, appliances, home life, commuting, and energy balance. Along with the criteria associated with the contests, the competition includes several design constraints that mirror those found in practical housing applications: including (but certainly not limited to) lot lines, building height, and ADA accessibility. The Solar Decathlon 2015 was held at the Orange Country Great Park in Irvine, CA. The 2015 competition was Clemson University’s first entry into the Solar Decathlon and was a notable milestone in the continued development of a home, called Indigo Pine. From the beginning, the team reconsidered the notion of sustainability as related to both the design of a home and the competition itself. The designing and building process for the home reflects a process which seamlessly moves between thinking and making to develop a comprehensive design with a method and innovations that challenge the conventions of residential construction. This report is a summary of the activities of the Clemson University team during the two-year duration of the project leading to the participation in the 2015 Solar Decathlon competition in Irvine California.

  3. Solar home systems in Nepal

    Energy Technology Data Exchange (ETDEWEB)

    Henryson, Jessica; Haakansson, Teresa

    1999-04-01

    Photovoltaic (PV) technology is a clean and environmentally friendly technology that does not require any fuels. The high reliability of operation and little need for maintenance makes it ideally suited for rural areas. Today PV systems are used in Nepal to power telecommunications centres, navigational aids, in pumping systems for irrigation and drinking water, and for household electrification. A solar home system consists of a PV module, a battery, a charge controller and 3-4 fluorescent light bulbs with fixture. The system provides power for lighting and operation of household appliances for several hours. The success of donor supported programs have shown that solar home systems can be a practical solution for many rural households. In 1996 the Government of Nepal launched a subsidy program for solar home systems, which dramatically has increased the demand for solar home systems among rural customers. This report includes a survey of 52 households with solar home systems in two villages. The field-study shows that the villagers are very happy with their systems and the technical performance of the systems in both villages is satisfactory. The study also shows the positive impact electricity has on education, health, income generation and quality of life. The beneficiaries of introducing electricity in remote areas are the children and the women 39 refs, 18 tabs. Examination paper

  4. Towards thermodynamical consistency of quasiparticle picture

    International Nuclear Information System (INIS)

    Biro, T.S.; Shanenko, A.A.; Toneev, V.D.; Research Inst. for Particle and Nuclear Physics, Hungarian Academy of Sciences, Budapest

    2003-01-01

    The purpose of the present article is to call attention to some realistic quasi-particle-based description of the quark/gluon matter and its consistent implementation in thermodynamics. A simple and transparent representation of the thermodynamical consistency conditions is given. This representation allows one to review critically and systemize available phenomenological approaches to the deconfinement problem with respect to their thermodynamical consistency. A particular attention is paid to the development of a method for treating the string screening in the dense matter of unbound color charges. The proposed method yields an integrable effective pair potential, which can be incorporated into the mean-field picture. The results of its application are in reasonable agreement with lattice data on the QCD thermodynamics [ru

  5. Toward thermodynamic consistency of quasiparticle picture

    International Nuclear Information System (INIS)

    Biro, T.S.; Toneev, V.D.; Shanenko, A.A.

    2003-01-01

    The purpose of the present article is to call attention to some realistic quasiparticle-based description of quark/gluon matter and its consistent implementation in thermodynamics. A simple and transparent representation of the thermodynamic consistency conditions is given. This representation allows one to review critically and systemize available phenomenological approaches to the deconfinement problem with respect to their thermodynamic consistency. Particular attention is paid to the development of a method for treating the string screening in the dense matter of unbound color charges. The proposed method yields an integrable effective pair potential that can be incorporated into the mean-field picture. The results of its application are in reasonable agreement with lattice data on the QCD thermodynamics

  6. Toward a consistent RHA-RPA

    International Nuclear Information System (INIS)

    Shepard, J.R.

    1991-01-01

    The authors examine the RPA based on a relativistic Hartree approximation description for nuclear ground states. This model includes contributions from the negative energy sea at the 1-loop level. They emphasize consistency between the treatment of the ground state and the RPA. This consistency is important in the description of low-lying collective levels but less important for the longitudinal (e, e') quasi-elastic response. They also study the effect of imposing a 3-momentum cutoff on negative energy sea contributions. A cutoff of twice the nucleon mass improves agreement with observed spin orbit splittings in nuclei compared to the standard infinite cutoff results, an effect traceable to the fact that imposing the cutoff reduces m*/m. The cutoff is much less important than consistency in the description of low-lying collective levels. The cutoff model provides excellent agreement with quasi-elastic (e, e') data

  7. Personalized recommendation based on unbiased consistence

    Science.gov (United States)

    Zhu, Xuzhen; Tian, Hui; Zhang, Ping; Hu, Zheng; Zhou, Tao

    2015-08-01

    Recently, in physical dynamics, mass-diffusion-based recommendation algorithms on bipartite network provide an efficient solution by automatically pushing possible relevant items to users according to their past preferences. However, traditional mass-diffusion-based algorithms just focus on unidirectional mass diffusion from objects having been collected to those which should be recommended, resulting in a biased causal similarity estimation and not-so-good performance. In this letter, we argue that in many cases, a user's interests are stable, and thus bidirectional mass diffusion abilities, no matter originated from objects having been collected or from those which should be recommended, should be consistently powerful, showing unbiased consistence. We further propose a consistence-based mass diffusion algorithm via bidirectional diffusion against biased causality, outperforming the state-of-the-art recommendation algorithms in disparate real data sets, including Netflix, MovieLens, Amazon and Rate Your Music.

  8. THE RISE AND FALL OF OPEN SOLAR FLUX DURING THE CURRENT GRAND SOLAR MAXIMUM

    International Nuclear Information System (INIS)

    Lockwood, M.; Rouillard, A. P.; Finch, I. D.

    2009-01-01

    We use geomagnetic activity data to study the rise and fall over the past century of the solar wind flow speed V SW , the interplanetary magnetic field strength B, and the open solar flux F S . Our estimates include allowance for the kinematic effect of longitudinal structure in the solar wind flow speed. As well as solar cycle variations, all three parameters show a long-term rise during the first half of the 20th century followed by peaks around 1955 and 1986 and then a recent decline. Cosmogenic isotope data reveal that this constitutes a grand maximum of solar activity which began in 1920, using the definition that such grand maxima are when 25-year averages of the heliospheric modulation potential exceeds 600 MV. Extrapolating the linear declines seen in all three parameters since 1985, yields predictions that the grand maximum will end in the years 2013, 2014, or 2027 using V SW , F S , or B, respectively. These estimates are consistent with predictions based on the probability distribution of the durations of past grand solar maxima seen in cosmogenic isotope data. The data contradict any suggestions of a floor to the open solar flux: we show that the solar minimum open solar flux, kinematically corrected to allow for the excess flux effect, has halved over the past two solar cycles.

  9. High Radiation Resistance IMM Solar Cell

    Science.gov (United States)

    Pan, Noren

    2015-01-01

    Due to high launch costs, weight reduction is a key driver for the development of new solar cell technologies suitable for space applications. This project is developing a unique triple-junction inverted metamorphic multijunction (IMM) technology that enables the manufacture of very lightweight, low-cost InGaAsP-based multijunction solar cells. This IMM technology consists of indium (In) and phosphorous (P) solar cell active materials, which are designed to improve the radiation-resistant properties of the triple-junction solar cell while maintaining high efficiency. The intrinsic radiation hardness of InP materials makes them of great interest for building solar cells suitable for deployment in harsh radiation environments, such as medium Earth orbit and missions to the outer planets. NASA Glenn's recently developed epitaxial lift-off (ELO) process also will be applied to this new structure, which will enable the fabrication of the IMM structure without the substrate.

  10. Organic Based Solar Cells with Morphology Control

    DEFF Research Database (Denmark)

    Andersen, Thomas Rieks

    The field of organic solar cells has in the last years gone through an impressive development with efficiencies reported up to 12 %. For organic solar cells to take the leap from primarily being a laboratory scale technology to being utilized as renewable energy source, several issues need...... Microscopy and as solar cells in a blend with PCBM. It was concluded that these particles did not show a potential large enough for continuous work due to a high material loss and low efficiency when applied in solar cells. The second method to achieve was preparation of pre-arranged morphology organic...... nanoparticles consisting of a blend of donor and acceptor in an aqueous dispersion, thereby addressing two of the issues remaining in the field of organic solar cells. This approach was used on six different polymers, which all had the ability to prepare aqueous nanoparticle inks. The morphology...

  11. The CRRES high efficiency solar panel

    International Nuclear Information System (INIS)

    Trumble, T.M.

    1991-01-01

    This paper reports on the High Efficiency Solar Panel (HESP) experiments which is to provide both engineering and scientific information concerning the effects of space radiation on advanced gallium arsenide (GaAs) solar cells. The HESP experiment consists of an ambient panel, and annealing panel and a programmable load. This experiment, in conjunction with the radiation measurement experiments abroad the CREES, provides the first opportunity to simultaneously measure the trapped radiation belts and the results of radiation damage to solar cells. The engineering information will result in a design guide for selecting the optimum solar array characteristics for different orbits and different lifetimes. The scientific information will provide both correlation of laboratory damage effects to space damage effects and a better model for predicting effective solar cell panel lifetimes

  12. Financial model calibration using consistency hints.

    Science.gov (United States)

    Abu-Mostafa, Y S

    2001-01-01

    We introduce a technique for forcing the calibration of a financial model to produce valid parameters. The technique is based on learning from hints. It converts simple curve fitting into genuine calibration, where broad conclusions can be inferred from parameter values. The technique augments the error function of curve fitting with consistency hint error functions based on the Kullback-Leibler distance. We introduce an efficient EM-type optimization algorithm tailored to this technique. We also introduce other consistency hints, and balance their weights using canonical errors. We calibrate the correlated multifactor Vasicek model of interest rates, and apply it successfully to Japanese Yen swaps market and US dollar yield market.

  13. Solar Energy Basics | NREL

    Science.gov (United States)

    Solar Energy Basics Solar Energy Basics Solar is the Latin word for sun-a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That's because more energy from the technologies convert sunlight to usable energy for buildings. The most commonly used solar technologies for

  14. A solar neutrino loophole: standard solar models

    Energy Technology Data Exchange (ETDEWEB)

    Rouse, C A [General Atomic Co., San Diego, Calif. (USA)

    1975-11-01

    The salient aspects of the existence theorem for a unique solution to a system of linear of nonlinear first-order, ordinary differential equations are given and applied to the equilibrium stellar structure equations. It is shown that values of pressure, temperature, mass and luminosity are needed at one point - and for the sun, the logical point is the solar radius. It is concluded that since standard solar model calculations use split boundary conditions, a solar neutrino loophole still remains: solar model calculations that seek to satisfy the necessary condition for a unique solution to the solar structure equations suggest a solar interior quite different from that deduced in standard models. This, in turn, suggests a theory of formation and solar evolution significantly different from the standard theory.

  15. Solar engine system

    International Nuclear Information System (INIS)

    Tan, K.K.; Bahrom Sanugi; Chen, L.C.; Chong, K.K.; Jasmy Yunus; Kannan, K.S.; Lim, B.H.; Noriah Bidin; Omar Aliman; Sahar Salehan; Sheikh Ab Rezan Sheikh A H; Tam, C.M.; Chen, Y.T.

    2001-01-01

    This paper reports the revolutionary solar engine system in Universiti Teknologi Malaysia (UTM). The solar engine is a single cylinder stirling engine driven by solar thermal energy. A first prototype solar engine has been built and demonstrated. A new-concept non-imaging focusing heliostat and a recently invented optical receiver are used in the demonstration. Second generation of prototype solar engine is described briefly. In this paper, the solar engine system development is reported. Measurement for the first prototype engine speed, temperature and specifications are presented. The benefits and potential applications for the future solar engine system, especially for the electricity generating aspect are discussed. (Author)

  16. Photovoltaic solar concentrator

    Science.gov (United States)

    Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J.; Sanchez, Carlos Anthony; Clews, Peggy J.; Gupta, Vipin P.

    2015-09-08

    A process including forming a photovoltaic solar cell on a substrate, the photovoltaic solar cell comprising an anchor positioned between the photovoltaic solar cell and the substrate to suspend the photovoltaic solar cell from the substrate. A surface of the photovoltaic solar cell opposite the substrate is attached to a receiving substrate. The receiving substrate may be bonded to the photovoltaic solar cell using an adhesive force or a metal connecting member. The photovoltaic solar cell is then detached from the substrate by lifting the receiving substrate having the photovoltaic solar cell attached thereto and severing the anchor connecting the photovoltaic solar cell to the substrate. Depending upon the type of receiving substrate used, the photovoltaic solar cell may be removed from the receiving substrate or remain on the receiving substrate for use in the final product.

  17. Solar workshops financial incentives

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-01-01

    Ten one-day workshops were held across the United States. Information in this workbook is compiled in conjunction with those workshops. The following discussions are included: solar as a fuel (history); why alternative fuels are being sought today; the need for conservation; advantages of solar energy; the potential of solar energy; why solar energy is not more widely used; a definition of solar; how solar can help meet energy demands; Federal policies and programs; what solar technologies exist today that can be effectively utilized (thermal applications, fuels from biomass, solar electric). Additional information is presented in three attachments: Energy-Conserving Methods; Domestic Policy Review of Solar Energy; and DOE Secretary's Annual Report to Congress-Solar Section. (MCW)

  18. Proteolysis and consistency of Meshanger cheese

    NARCIS (Netherlands)

    Jong, de L.

    1978-01-01

    Proteolysis in Meshanger cheese, estimated by quantitative polyacrylamide gel electrophoresis is discussed. The conversion of α s1 -casein was proportional to rennet concentration in the cheese. Changes in consistency, after a maximum, were correlated to breakdown of

  19. Developing consistent pronunciation models for phonemic variants

    CSIR Research Space (South Africa)

    Davel, M

    2006-09-01

    Full Text Available Pronunciation lexicons often contain pronunciation variants. This can create two problems: It can be difficult to define these variants in an internally consistent way and it can also be difficult to extract generalised grapheme-to-phoneme rule sets...

  20. Image recognition and consistency of response

    Science.gov (United States)

    Haygood, Tamara M.; Ryan, John; Liu, Qing Mary A.; Bassett, Roland; Brennan, Patrick C.

    2012-02-01

    Purpose: To investigate the connection between conscious recognition of an image previously encountered in an experimental setting and consistency of response to the experimental question. Materials and Methods: Twenty-four radiologists viewed 40 frontal chest radiographs and gave their opinion as to the position of a central venous catheter. One-to-three days later they again viewed 40 frontal chest radiographs and again gave their opinion as to the position of the central venous catheter. Half of the radiographs in the second set were repeated images from the first set and half were new. The radiologists were asked of each image whether it had been included in the first set. For this study, we are evaluating only the 20 repeated images. We used the Kruskal-Wallis test and Fisher's exact test to determine the relationship between conscious recognition of a previously interpreted image and consistency in interpretation of the image. Results. There was no significant correlation between recognition of the image and consistency in response regarding the position of the central venous catheter. In fact, there was a trend in the opposite direction, with radiologists being slightly more likely to give a consistent response with respect to images they did not recognize than with respect to those they did recognize. Conclusion: Radiologists' recognition of previously-encountered images in an observer-performance study does not noticeably color their interpretation on the second encounter.

  1. Consistent Valuation across Curves Using Pricing Kernels

    Directory of Open Access Journals (Sweden)

    Andrea Macrina

    2018-03-01

    Full Text Available The general problem of asset pricing when the discount rate differs from the rate at which an asset’s cash flows accrue is considered. A pricing kernel framework is used to model an economy that is segmented into distinct markets, each identified by a yield curve having its own market, credit and liquidity risk characteristics. The proposed framework precludes arbitrage within each market, while the definition of a curve-conversion factor process links all markets in a consistent arbitrage-free manner. A pricing formula is then derived, referred to as the across-curve pricing formula, which enables consistent valuation and hedging of financial instruments across curves (and markets. As a natural application, a consistent multi-curve framework is formulated for emerging and developed inter-bank swap markets, which highlights an important dual feature of the curve-conversion factor process. Given this multi-curve framework, existing multi-curve approaches based on HJM and rational pricing kernel models are recovered, reviewed and generalised and single-curve models extended. In another application, inflation-linked, currency-based and fixed-income hybrid securities are shown to be consistently valued using the across-curve valuation method.

  2. Guided color consistency optimization for image mosaicking

    Science.gov (United States)

    Xie, Renping; Xia, Menghan; Yao, Jian; Li, Li

    2018-01-01

    This paper studies the problem of color consistency correction for sequential images with diverse color characteristics. Existing algorithms try to adjust all images to minimize color differences among images under a unified energy framework, however, the results are prone to presenting a consistent but unnatural appearance when the color difference between images is large and diverse. In our approach, this problem is addressed effectively by providing a guided initial solution for the global consistency optimization, which avoids converging to a meaningless integrated solution. First of all, to obtain the reliable intensity correspondences in overlapping regions between image pairs, we creatively propose the histogram extreme point matching algorithm which is robust to image geometrical misalignment to some extents. In the absence of the extra reference information, the guided initial solution is learned from the major tone of the original images by searching some image subset as the reference, whose color characteristics will be transferred to the others via the paths of graph analysis. Thus, the final results via global adjustment will take on a consistent color similar to the appearance of the reference image subset. Several groups of convincing experiments on both the synthetic dataset and the challenging real ones sufficiently demonstrate that the proposed approach can achieve as good or even better results compared with the state-of-the-art approaches.

  3. Consistent application of codes and standards

    International Nuclear Information System (INIS)

    Scott, M.A.

    1989-01-01

    The guidelines presented in the US Department of Energy, General Design Criteria (DOE 6430.1A), and the Design and Evaluation Guidelines for Department of Energy Facilities Subject to Natural Phenomena Hazards (UCRL-15910) provide a consistent and well defined approach to determine the natural phenomena hazards loads for US Department of Energy site facilities. The guidelines for the application of loads combinations and allowables criteria are not as well defined and are more flexible in interpretation. This flexibility in the interpretation of load combinations can lead to conflict between the designer and overseer. The establishment of an efficient set of acceptable design criteria, based on US Department of Energy guidelines, provides a consistent baseline for analysis, design, and review. Additionally, the proposed method should not limit the design and analytical innovation necessary to analyze or qualify the unique structure. This paper investigates the consistent application of load combinations, analytical methods, and load allowables and suggests a reference path consistent with the US Department of Energy guidelines

  4. Consistency in multi-viewpoint architectural design

    NARCIS (Netherlands)

    Dijkman, R.M.; Dijkman, Remco Matthijs

    2006-01-01

    This thesis presents a framework that aids in preserving consistency in multi-viewpoint designs. In a multi-viewpoint design each stakeholder constructs his own design part. We call each stakeholder’s design part the view of that stakeholder. To construct his view, a stakeholder has a viewpoint.

  5. Consistent Visual Analyses of Intrasubject Data

    Science.gov (United States)

    Kahng, SungWoo; Chung, Kyong-Mee; Gutshall, Katharine; Pitts, Steven C.; Kao, Joyce; Girolami, Kelli

    2010-01-01

    Visual inspection of single-case data is the primary method of interpretation of the effects of an independent variable on a dependent variable in applied behavior analysis. The purpose of the current study was to replicate and extend the results of DeProspero and Cohen (1979) by reexamining the consistency of visual analysis across raters. We…

  6. Consistent Stochastic Modelling of Meteocean Design Parameters

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Sterndorff, M. J.

    2000-01-01

    Consistent stochastic models of metocean design parameters and their directional dependencies are essential for reliability assessment of offshore structures. In this paper a stochastic model for the annual maximum values of the significant wave height, and the associated wind velocity, current...

  7. On the existence of consistent price systems

    DEFF Research Database (Denmark)

    Bayraktar, Erhan; Pakkanen, Mikko S.; Sayit, Hasanjan

    2014-01-01

    We formulate a sufficient condition for the existence of a consistent price system (CPS), which is weaker than the conditional full support condition (CFS). We use the new condition to show the existence of CPSs for certain processes that fail to have the CFS property. In particular this condition...

  8. Dynamic phonon exchange requires consistent dressing

    International Nuclear Information System (INIS)

    Hahne, F.J.W.; Engelbrecht, C.A.; Heiss, W.D.

    1976-01-01

    It is shown that states with undersirable properties (such as ghosts, states with complex eigenenergies and states with unrestricted normalization) emerge from two-body calculations using dynamic effective interactions if one is not careful in introducing single-particle self-energy insertions in a consistent manner

  9. Consistent feeding positions of great tit parents

    NARCIS (Netherlands)

    Lessells, C.M.; Poelman, E.H.; Mateman, A.C.; Cassey, Ph.

    2006-01-01

    When parent birds arrive at the nest to provision their young, their position on the nest rim may influence which chick or chicks are fed. As a result, the consistency of feeding positions of the individual parents, and the difference in position between the parents, may affect how equitably food is

  10. Consistency of the postulates of special relativity

    International Nuclear Information System (INIS)

    Gron, O.; Nicola, M.

    1976-01-01

    In a recent article in this journal, Kingsley has tried to show that the postulates of special relativity contradict each other. It is shown that the arguments of Kingsley are invalid because of an erroneous appeal to symmetry in a nonsymmetric situation. The consistency of the postulates of special relativity and the relativistic kinematics deduced from them is restated

  11. Consistency of Network Traffic Repositories: An Overview

    NARCIS (Netherlands)

    Lastdrager, E.; Lastdrager, E.E.H.; Pras, Aiko

    2009-01-01

    Traffc repositories with TCP/IP header information are very important for network analysis. Researchers often assume that such repositories reliably represent all traffc that has been flowing over the network; little thoughts are made regarding the consistency of these repositories. Still, for

  12. Consistency analysis of network traffic repositories

    NARCIS (Netherlands)

    Lastdrager, Elmer; Lastdrager, E.E.H.; Pras, Aiko

    Traffic repositories with TCP/IP header information are very important for network analysis. Researchers often assume that such repositories reliably represent all traffic that has been flowing over the network; little thoughts are made regarding the consistency of these repositories. Still, for

  13. Solar collector performance evaluated outdoors at NASA-Lewis Research Center

    Science.gov (United States)

    Vernon, R. W.

    1974-01-01

    The study of solar reflector performance reported is related to a project in which solar collectors are to be provided for the solar heating and cooling system of an office building at NASA's Langley Research Center. The solar collector makes use of a liquid consisting of 50% ethylene glycol and 50% water. A conventional air-liquid heat exchanger is employed. Collector performance and solar insolation data are recorded along with air temperature, wind speed and direction, and relative humidity.

  14. Solar collector array

    Science.gov (United States)

    Hall, John Champlin; Martins, Guy Lawrence

    2015-09-06

    A method and apparatus for efficient manufacture, assembly and production of solar energy. In one aspect, the apparatus may include a number of modular solar receiver assemblies that may be separately manufactured, assembled and individually inserted into a solar collector array housing shaped to receive a plurality of solar receivers. The housing may include optical elements for focusing light onto the individual receivers, and a circuit for electrically connecting the solar receivers.

  15. Solar heating and cooling.

    Science.gov (United States)

    Duffie, J A

    1976-01-01

    Solar energy is discussed as an energy resource that can be converted into useful energy forms to meet a variety of energy needs. The review briefly explains the nature of this energy resource, the kinds of applications that can be made useful, and the status of several systems to which it has been applied. More specifically, information on solar collectors, solar water heating, solar heating of buildings, solar cooling plus other applications, are included.

  16. UARS Solar-Stellar Irradiance Comparison Experiment (SOLSTICE) Level 3BS V001

    Data.gov (United States)

    National Aeronautics and Space Administration — The Solar-Stellar Irradiance Comparison Experiment (SOLSTICE) Level 3BS data product consists of daily, 1 nm resolution, solar spectral irradiances and selected...

  17. Discrete symmetries and solar neutrino mixing

    Energy Technology Data Exchange (ETDEWEB)

    Kapetanakis, D.; Mayr, P.; Nilles, H.P. (Physik Dept., Technische Univ. Muenchen, Garching (Germany) Max-Planck-Inst. fuer Physik, Werner-Heisenberg-Inst., Muenchen (Germany))

    1992-05-21

    We study the question of resonant solar neutrino mixing in the framework of the supersymmetric extension of the standard model. Discrete symmetries that are consistent with solar neutrino mixing and proton stability are classified. In the minimal model they are shown to lead to two distinct patterns of allowed dimension-four operators. Imposing anomaly freedom, only three different discrete Z{sub N}-symmetries (with N=2, 3, 6) are found to be phenomenologically acceptable. (orig.).

  18. Discrete symmetries and solar neutrino mixing

    International Nuclear Information System (INIS)

    Kapetanakis, D.; Mayr, P.; Nilles, H.P.

    1992-01-01

    We study the question of resonant solar neutrino mixing in the framework of the supersymmetric extension of the standard model. Discrete symmetries that are consistent with solar neutrino mixing and proton stability are classified. In the minimal model they are shown to lead to two distinct patterns of allowed dimension-four operators. Imposing anomaly freedom, only three different discrete Z N -symmetries (with N=2, 3, 6) are found to be phenomenologically acceptable. (orig.)

  19. First Colombian Solar Radio Interferometer: current stage

    Science.gov (United States)

    Guevara Gómez, J. C.; Martínez Oliveros, J. C.; Calvo-Mozo, B.

    2017-10-01

    Solar radio astronomy is a fast developing research field in Colombia. Here, we present the scientific goals, specifications and current state of the First Colombian Solar Radio Interferometer consisting of two log-periodic antennas covering a frequency bandwidth op to 800 MHz. We describe the importance and benefits of its development to the radioastronomy in Latin America and its impact on the scientific community and general public.

  20. Solar energy thermalization and storage device

    Science.gov (United States)

    McClelland, J.F.

    A passive solar thermalization and thermal energy storage assembly which is visually transparent is described. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  1. Self-consistent stationary MHD shear flows in the solar atmosphere as electric field generators

    Czech Academy of Sciences Publication Activity Database

    Nickeler, Dieter Horst; Karlický, Marian; Wiegelmann, T.; Kraus, Michaela

    2014-01-01

    Roč. 569, September (2014), A44/1-A44/10 ISSN 0004-6361 R&D Projects: GA ČR GA13-24782S; GA ČR GAP209/12/0103 Institutional support: RVO:67985815 Keywords : magnetohydrodynamics * Sum : flares * Sun : corona Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.378, year: 2014

  2. A consistent interpretation of quantum mechanics

    International Nuclear Information System (INIS)

    Omnes, Roland

    1990-01-01

    Some mostly recent theoretical and mathematical advances can be linked together to yield a new consistent interpretation of quantum mechanics. It relies upon a unique and universal interpretative rule of a logical character which is based upon Griffiths consistent history. Some new results in semi-classical physics allow classical physics to be derived from this rule, including its logical aspects, and to prove accordingly the existence of determinism within the quantum framework. Together with decoherence, this can be used to retrieve the existence of facts, despite the probabilistic character of the theory. Measurement theory can then be made entirely deductive. It is accordingly found that wave packet reduction is a logical property, whereas one can always choose to avoid using it. The practical consequences of this interpretation are most often in agreement with the Copenhagen formulation but they can be proved never to give rise to any logical inconsistency or paradox. (author)

  3. Self-consistency in Capital Markets

    Science.gov (United States)

    Benbrahim, Hamid

    2013-03-01

    Capital Markets are considered, at least in theory, information engines whereby traders contribute to price formation with their diverse perspectives. Regardless whether one believes in efficient market theory on not, actions by individual traders influence prices of securities, which in turn influence actions by other traders. This influence is exerted through a number of mechanisms including portfolio balancing, margin maintenance, trend following, and sentiment. As a result market behaviors emerge from a number of mechanisms ranging from self-consistency due to wisdom of the crowds and self-fulfilling prophecies, to more chaotic behavior resulting from dynamics similar to the three body system, namely the interplay between equities, options, and futures. This talk will address questions and findings regarding the search for self-consistency in capital markets.

  4. Student Effort, Consistency and Online Performance

    Directory of Open Access Journals (Sweden)

    Hilde Patron

    2011-07-01

    Full Text Available This paper examines how student effort, consistency, motivation, and marginal learning, influence student grades in an online course. We use data from eleven Microeconomics courses taught online for a total of 212 students. Our findings show that consistency, or less time variation, is a statistically significant explanatory variable, whereas effort, or total minutes spent online, is not. Other independent variables include GPA and the difference between a pre-test and a post-test. The GPA is used as a measure of motivation, and the difference between a post-test and pre-test as marginal learning. As expected, the level of motivation is found statistically significant at a 99% confidence level, and marginal learning is also significant at a 95% level.

  5. Consistent thermodynamic properties of lipids systems

    DEFF Research Database (Denmark)

    Cunico, Larissa; Ceriani, Roberta; Sarup, Bent

    different pressures, with azeotrope behavior observed. Available thermodynamic consistency tests for TPx data were applied before performing parameter regressions for Wilson, NRTL, UNIQUAC and original UNIFAC models. The relevance of enlarging experimental databank of lipids systems data in order to improve......Physical and thermodynamic properties of pure components and their mixtures are the basic requirement for process design, simulation, and optimization. In the case of lipids, our previous works[1-3] have indicated a lack of experimental data for pure components and also for their mixtures...... the performance of predictive thermodynamic models was confirmed in this work by analyzing the calculated values of original UNIFAC model. For solid-liquid equilibrium (SLE) data, new consistency tests have been developed [2]. Some of the developed tests were based in the quality tests proposed for VLE data...

  6. Consistency relation for cosmic magnetic fields

    DEFF Research Database (Denmark)

    Jain, R. K.; Sloth, M. S.

    2012-01-01

    If cosmic magnetic fields are indeed produced during inflation, they are likely to be correlated with the scalar metric perturbations that are responsible for the cosmic microwave background anisotropies and large scale structure. Within an archetypical model of inflationary magnetogenesis, we show...... that there exists a new simple consistency relation for the non-Gaussian cross correlation function of the scalar metric perturbation with two powers of the magnetic field in the squeezed limit where the momentum of the metric perturbation vanishes. We emphasize that such a consistency relation turns out...... to be extremely useful to test some recent calculations in the literature. Apart from primordial non-Gaussianity induced by the curvature perturbations, such a cross correlation might provide a new observational probe of inflation and can in principle reveal the primordial nature of cosmic magnetic fields. DOI...

  7. Consistent Estimation of Partition Markov Models

    Directory of Open Access Journals (Sweden)

    Jesús E. García

    2017-04-01

    Full Text Available The Partition Markov Model characterizes the process by a partition L of the state space, where the elements in each part of L share the same transition probability to an arbitrary element in the alphabet. This model aims to answer the following questions: what is the minimal number of parameters needed to specify a Markov chain and how to estimate these parameters. In order to answer these questions, we build a consistent strategy for model selection which consist of: giving a size n realization of the process, finding a model within the Partition Markov class, with a minimal number of parts to represent the process law. From the strategy, we derive a measure that establishes a metric in the state space. In addition, we show that if the law of the process is Markovian, then, eventually, when n goes to infinity, L will be retrieved. We show an application to model internet navigation patterns.

  8. Internal Branding and Employee Brand Consistent Behaviours

    DEFF Research Database (Denmark)

    Mazzei, Alessandra; Ravazzani, Silvia

    2017-01-01

    constitutive processes. In particular, the paper places emphasis on the role and kinds of communication practices as a central part of the nonnormative and constitutive internal branding process. The paper also discusses an empirical study based on interviews with 32 Italian and American communication managers...... and 2 focus groups with Italian communication managers. Findings show that, in order to enhance employee brand consistent behaviours, the most effective communication practices are those characterised as enablement-oriented. Such a communication creates the organizational conditions adequate to sustain......Employee behaviours conveying brand values, named brand consistent behaviours, affect the overall brand evaluation. Internal branding literature highlights a knowledge gap in terms of communication practices intended to sustain such behaviours. This study contributes to the development of a non...

  9. Self-consistent velocity dependent effective interactions

    International Nuclear Information System (INIS)

    Kubo, Takayuki; Sakamoto, Hideo; Kammuri, Tetsuo; Kishimoto, Teruo.

    1993-09-01

    The field coupling method is extended to a system with a velocity dependent mean potential. By means of this method, we can derive the effective interactions which are consistent with the mean potential. The self-consistent velocity dependent effective interactions are applied to the microscopic analysis of the structures of giant dipole resonances (GDR) of 148,154 Sm, of the first excited 2 + states of Sn isotopes and of the first excited 3 - states of Mo isotopes. It is clarified that the interactions play crucial roles in describing the splitting of the resonant structure of GDR peaks, in restoring the energy weighted sum rule values, and in reducing B (Eλ) values. (author)

  10. Nanostructured refractory thin films for solar applications

    Science.gov (United States)

    Ollier, E.; Dunoyer, N.; Dellea, O.; Szambolics, H.

    2014-08-01

    Selective solar absorbers are key elements of all solar thermal systems. Solar thermal panels and Concentrated Solar Power (CSP) systems aim respectively at producing heat and electricity. In both cases, a surface receives the solar radiation and is designed to have the highest optical absorption (lowest optical reflectivity) of the solar radiation in the visible wavelength range where the solar intensity is the highest. It also has a low emissivity in the infrared (IR) range in order to avoid radiative thermal losses. Current solutions in the state of the art usually consist in deposited interferential thin films or in cermets [1]. Structured surfaces have been proposed and have been simulated because they are supposed to be more efficient when the solar radiation is not normal to the receiving surface and because they could potentially be fabricated with refractory materials able to sustain high operating temperatures. This work presents a new method to fabricate micro/nanostructured surfaces on molybdenum (refractory metal with a melting temperature of 2623°C). This method now allows obtaining a refractory selective surface with an excellent optical selectivity and a very high absorption in the visible range. This high absorption performance was obtained by achieving a double structuration at micro and nano scales thanks to an innovative process flow.

  11. Solar Club

    CERN Multimedia

    Solar Club

    2012-01-01

      Le  CERN Solar Club tiendra son Assemblée Générale le Mercredi  4 avril, à 18h00 dans la salle C, bat.61, 1e étage de 18h00  à  19h30. Grande table ronde avec  présentations de projets concernant toute forme d’Energie  Renouvelable par des membres du club,  et… par  VOUS, nos invités. Au programme : - L’E-push : petite remorque électrique, qui pousse vôtre vélo par Robert Becker. - Le Stockage Saisonnier Sous-Lacustre d’Energie Solaire (S3LES) par  William van Sprolant. - Compte-Rendu de plusieurs conférences récentes concernant les E.R. par Jacques Dupin. - VOS  Projets ou Sujets (contactez : paul.gelissen@orange.fr). - Partie «administrative» avec rapport d’activités, rapport fina...

  12. Solar possibilities

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, D

    1979-01-01

    A major energy transition of some kind is inevitable. For rich lands and poor alike, the energy patterns of the past are not prologue to the future. The oil-based societies of the industrial world cannot be sustained and cannot be replicated. The huge increases in oil prices since 1973 virtually guarantee that the Third World will never derive most of its energy from petroleum. Gross world oil production is likely to peak within the next decade; per capita world oil production may have already peaked. The world thus faces an awesome discontinuity in the production and use of energy. In the past, such energy transformations invariably produced far-reaching social change. The 18th-century substitution of coal for wood and wind in Europe, for example, accelerated and refashioned the industrial revolution. Later, the shift to petroleum altered the nature of travel, shrinking the planet and reshaping its cities. The coming energy transition can be counted upon to fundamentally alter tomorrow's world. This will be as true of a solar era as of a nuclear age. Sunlight is abundant, dependable, and free. With some minor fluctuations, the sun has been bestowing its bounty on the earth for more than four billion years, and it is expected to continue to do so for several billion more. The use of photovoltaic, wind power, biomass conversion, and hydro power for energy production are also discussed.

  13. Solar flares

    International Nuclear Information System (INIS)

    Brown, J.C.; Smith, D.F.

    1980-01-01

    The current observational and theoretical status of solar flares as a typical astrophysical problem is reviewed with especial reference to the intense and complex energy release in large flares. Observations and their diagnostic applications are discussed in three broad areas: thermal radiation at temperatures T 5 K; thermal radiation at T > approximately 10 5 K; and non-thermal radiation and particles. Particular emphasis is given to the most recent observational discoveries such as flare γ-rays, interplanetary Langmuir waves, and the ubiquitous association of soft x-ray loops with flares, and also the progress in particle diagnostics of hard x-ray and radio bursts. The theoretical problems of primary energy release are considered in terms of both possible magnetic configuration and in plasma instabilities and the question of achieving the necessary flash power discussed. The credibility of models for the secondary redistribution through the atmosphere of the primary magnetic energy released in terms of conduction, convection, radiation and particle transport is examined. Progress made in the flare problem in the past decade is assessed and some possible reasons why no convincing solution has yet been found are considered. 296 references. (U.K.)

  14. Cascade Organic Solar Cells

    KAUST Repository

    Schlenker, Cody W.

    2011-09-27

    We demonstrate planar organic solar cells consisting of a series of complementary donor materials with cascading exciton energies, incorporated in the following structure: glass/indium-tin-oxide/donor cascade/C 60/bathocuproine/Al. Using a tetracene layer grown in a descending energy cascade on 5,6-diphenyl-tetracene and capped with 5,6,11,12-tetraphenyl- tetracene, where the accessibility of the π-system in each material is expected to influence the rate of parasitic carrier leakage and charge recombination at the donor/acceptor interface, we observe an increase in open circuit voltage (Voc) of approximately 40% (corresponding to a change of +200 mV) compared to that of a single tetracene donor. Little change is observed in other parameters such as fill factor and short circuit current density (FF = 0.50 ± 0.02 and Jsc = 2.55 ± 0.23 mA/cm2) compared to those of the control tetracene-C60 solar cells (FF = 0.54 ± 0.02 and Jsc = 2.86 ± 0.23 mA/cm2). We demonstrate that this cascade architecture is effective in reducing losses due to polaron pair recombination at donor-acceptor interfaces, while enhancing spectral coverage, resulting in a substantial increase in the power conversion efficiency for cascade organic photovoltaic cells compared to tetracene and pentacene based devices with a single donor layer. © 2011 American Chemical Society.

  15. Cascade Organic Solar Cells

    KAUST Repository

    Schlenker, Cody W.; Barlier, Vincent S.; Chin, Stephanie W.; Whited, Matthew T.; McAnally, R. Eric; Forrest, Stephen R.; Thompson, Mark E.

    2011-01-01

    We demonstrate planar organic solar cells consisting of a series of complementary donor materials with cascading exciton energies, incorporated in the following structure: glass/indium-tin-oxide/donor cascade/C 60/bathocuproine/Al. Using a tetracene layer grown in a descending energy cascade on 5,6-diphenyl-tetracene and capped with 5,6,11,12-tetraphenyl- tetracene, where the accessibility of the π-system in each material is expected to influence the rate of parasitic carrier leakage and charge recombination at the donor/acceptor interface, we observe an increase in open circuit voltage (Voc) of approximately 40% (corresponding to a change of +200 mV) compared to that of a single tetracene donor. Little change is observed in other parameters such as fill factor and short circuit current density (FF = 0.50 ± 0.02 and Jsc = 2.55 ± 0.23 mA/cm2) compared to those of the control tetracene-C60 solar cells (FF = 0.54 ± 0.02 and Jsc = 2.86 ± 0.23 mA/cm2). We demonstrate that this cascade architecture is effective in reducing losses due to polaron pair recombination at donor-acceptor interfaces, while enhancing spectral coverage, resulting in a substantial increase in the power conversion efficiency for cascade organic photovoltaic cells compared to tetracene and pentacene based devices with a single donor layer. © 2011 American Chemical Society.

  16. Evaluating Temporal Consistency in Marine Biodiversity Hotspots

    OpenAIRE

    Piacenza, Susan E.; Thurman, Lindsey L.; Barner, Allison K.; Benkwitt, Cassandra E.; Boersma, Kate S.; Cerny-Chipman, Elizabeth B.; Ingeman, Kurt E.; Kindinger, Tye L.; Lindsley, Amy J.; Nelson, Jake; Reimer, Jessica N.; Rowe, Jennifer C.; Shen, Chenchen; Thompson, Kevin A.; Heppell, Selina S.

    2015-01-01

    With the ongoing crisis of biodiversity loss and limited resources for conservation, the concept of biodiversity hotspots has been useful in determining conservation priority areas. However, there has been limited research into how temporal variability in biodiversity may influence conservation area prioritization. To address this information gap, we present an approach to evaluate the temporal consistency of biodiversity hotspots in large marine ecosystems. Using a large scale, public monito...

  17. Cloud Standardization: Consistent Business Processes and Information

    Directory of Open Access Journals (Sweden)

    Razvan Daniel ZOTA

    2013-01-01

    Full Text Available Cloud computing represents one of the latest emerging trends in distributed computing that enables the existence of hardware infrastructure and software applications as services. The present paper offers a general approach to the cloud computing standardization as a mean of improving the speed of adoption for the cloud technologies. Moreover, this study tries to show out how organizations may achieve more consistent business processes while operating with cloud computing technologies.

  18. Consistency Analysis of Nearest Subspace Classifier

    OpenAIRE

    Wang, Yi

    2015-01-01

    The Nearest subspace classifier (NSS) finds an estimation of the underlying subspace within each class and assigns data points to the class that corresponds to its nearest subspace. This paper mainly studies how well NSS can be generalized to new samples. It is proved that NSS is strongly consistent under certain assumptions. For completeness, NSS is evaluated through experiments on various simulated and real data sets, in comparison with some other linear model based classifiers. It is also ...

  19. Consistency relations in effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Munshi, Dipak; Regan, Donough, E-mail: D.Munshi@sussex.ac.uk, E-mail: D.Regan@sussex.ac.uk [Astronomy Centre, School of Mathematical and Physical Sciences, University of Sussex, Brighton BN1 9QH (United Kingdom)

    2017-06-01

    The consistency relations in large scale structure relate the lower-order correlation functions with their higher-order counterparts. They are direct outcome of the underlying symmetries of a dynamical system and can be tested using data from future surveys such as Euclid. Using techniques from standard perturbation theory (SPT), previous studies of consistency relation have concentrated on continuity-momentum (Euler)-Poisson system of an ideal fluid. We investigate the consistency relations in effective field theory (EFT) which adjusts the SPT predictions to account for the departure from the ideal fluid description on small scales. We provide detailed results for the 3D density contrast δ as well as the scaled divergence of velocity θ-bar . Assuming a ΛCDM background cosmology, we find the correction to SPT results becomes important at k ∼> 0.05 h/Mpc and that the suppression from EFT to SPT results that scales as square of the wave number k , can reach 40% of the total at k ≈ 0.25 h/Mpc at z = 0. We have also investigated whether effective field theory corrections to models of primordial non-Gaussianity can alter the squeezed limit behaviour, finding the results to be rather insensitive to these counterterms. In addition, we present the EFT corrections to the squeezed limit of the bispectrum in redshift space which may be of interest for tests of theories of modified gravity.

  20. Consistent probabilities in loop quantum cosmology

    International Nuclear Information System (INIS)

    Craig, David A; Singh, Parampreet

    2013-01-01

    A fundamental issue for any quantum cosmological theory is to specify how probabilities can be assigned to various quantum events or sequences of events such as the occurrence of singularities or bounces. In previous work, we have demonstrated how this issue can be successfully addressed within the consistent histories approach to quantum theory for Wheeler–DeWitt-quantized cosmological models. In this work, we generalize that analysis to the exactly solvable loop quantization of a spatially flat, homogeneous and isotropic cosmology sourced with a massless, minimally coupled scalar field known as sLQC. We provide an explicit, rigorous and complete decoherent-histories formulation for this model and compute the probabilities for the occurrence of a quantum bounce versus a singularity. Using the scalar field as an emergent internal time, we show for generic states that the probability for a singularity to occur in this model is zero, and that of a bounce is unity, complementing earlier studies of the expectation values of the volume and matter density in this theory. We also show from the consistent histories point of view that all states in this model, whether quantum or classical, achieve arbitrarily large volume in the limit of infinite ‘past’ or ‘future’ scalar ‘time’, in the sense that the wave function evaluated at any arbitrary fixed value of the volume vanishes in that limit. Finally, we briefly discuss certain misconceptions concerning the utility of the consistent histories approach in these models. (paper)

  1. Orthology and paralogy constraints: satisfiability and consistency.

    Science.gov (United States)

    Lafond, Manuel; El-Mabrouk, Nadia

    2014-01-01

    A variety of methods based on sequence similarity, reconciliation, synteny or functional characteristics, can be used to infer orthology and paralogy relations between genes of a given gene family  G. But is a given set  C of orthology/paralogy constraints possible, i.e., can they simultaneously co-exist in an evolutionary history for  G? While previous studies have focused on full sets of constraints, here we consider the general case where  C does not necessarily involve a constraint for each pair of genes. The problem is subdivided in two parts: (1) Is  C satisfiable, i.e. can we find an event-labeled gene tree G inducing  C? (2) Is there such a G which is consistent, i.e., such that all displayed triplet phylogenies are included in a species tree? Previous results on the Graph sandwich problem can be used to answer to (1), and we provide polynomial-time algorithms for satisfiability and consistency with a given species tree. We also describe a new polynomial-time algorithm for the case of consistency with an unknown species tree and full knowledge of pairwise orthology/paralogy relationships, as well as a branch-and-bound algorithm in the case when unknown relations are present. We show that our algorithms can be used in combination with ProteinOrtho, a sequence similarity-based orthology detection tool, to extract a set of robust orthology/paralogy relationships.

  2. Consistency of color representation in smart phones.

    Science.gov (United States)

    Dain, Stephen J; Kwan, Benjamin; Wong, Leslie

    2016-03-01

    One of the barriers to the construction of consistent computer-based color vision tests has been the variety of monitors and computers. Consistency of color on a variety of screens has necessitated calibration of each setup individually. Color vision examination with a carefully controlled display has, as a consequence, been a laboratory rather than a clinical activity. Inevitably, smart phones have become a vehicle for color vision tests. They have the advantage that the processor and screen are associated and there are fewer models of smart phones than permutations of computers and monitors. Colorimetric consistency of display within a model may be a given. It may extend across models from the same manufacturer but is unlikely to extend between manufacturers especially where technologies vary. In this study, we measured the same set of colors in a JPEG file displayed on 11 samples of each of four models of smart phone (iPhone 4s, iPhone5, Samsung Galaxy S3, and Samsung Galaxy S4) using a Photo Research PR-730. The iPhones are white LED backlit LCD and the Samsung are OLEDs. The color gamut varies between models and comparison with sRGB space shows 61%, 85%, 117%, and 110%, respectively. The iPhones differ markedly from the Samsungs and from one another. This indicates that model-specific color lookup tables will be needed. Within each model, the primaries were quite consistent (despite the age of phone varying within each sample). The worst case in each model was the blue primary; the 95th percentile limits in the v' coordinate were ±0.008 for the iPhone 4 and ±0.004 for the other three models. The u'v' variation in white points was ±0.004 for the iPhone4 and ±0.002 for the others, although the spread of white points between models was u'v'±0.007. The differences are essentially the same for primaries at low luminance. The variation of colors intermediate between the primaries (e.g., red-purple, orange) mirror the variation in the primaries. The variation in

  3. Do Health Systems Have Consistent Performance Across Locations and Is Consistency Associated With Higher Performance?

    Science.gov (United States)

    Crespin, Daniel J; Christianson, Jon B; McCullough, Jeffrey S; Finch, Michael D

    This study addresses whether health systems have consistent diabetes care performance across their ambulatory clinics and whether increasing consistency is associated with improvements in clinic performance. Study data included 2007 to 2013 diabetes care intermediate outcome measures for 661 ambulatory clinics in Minnesota and bordering states. Health systems provided more consistent performance, as measured by the standard deviation of performance for clinics in a system, relative to propensity score-matched proxy systems created for comparison purposes. No evidence was found that improvements in consistency were associated with higher clinic performance. The combination of high performance and consistent care is likely to enhance a health system's brand reputation, allowing it to better mitigate the financial risks of consumers seeking care outside the organization. These results suggest that larger health systems are most likely to deliver the combination of consistent and high-performance care. Future research should explore the mechanisms that drive consistent care within health systems.

  4. Solar Design Workbook

    Energy Technology Data Exchange (ETDEWEB)

    Franta, G.; Baylin, F.; Crowther, R.; Dubin, F.; Grace, A., Griffith, J.W.; Holtz, M.; Kutscher, C.; Nordham, D.; Selkowitz, S.; Villecco, M.

    1981-06-01

    This Solar Design Workbook presents solar building design applications for commercial buildir^s. The book is divided into four sections. The first section describes the variety of solar applications in buildings including conservation aspects, solar fundamentals, passive systems, active systems, daylighting, and other solar options. Solar system design evaluation techniques including considerations for building energy requirements, passive systems, active systems, and economics are presented in Section II. The third section attempts to assist the designer in the building design process for energy conservation and solar applications including options and considerations for pre-design, design, and post-design phases. The information required for the solar design proee^ has not been fully developed at this time. Therefore, Section III is incomplete, but an overview of the considerations with some of the design proces elements is presented. Section IV illustrates ease studies that utilize solar applications in the building design.

  5. Seguidor Solar, optimizando el aprovechamiento de la energía solar ; Solar tracker, optimizing ofimprovementof the solar energy

    Directory of Open Access Journals (Sweden)

    Noel Machado Toranzo

    2015-06-01

    Full Text Available En este trabajo se realizó el diseño e implementación de un dispositivo encargado de obtener las coordenadas del Sol en cualquier momento del día, es decir, un seguidor solar a dos ejes por punto luminoso. Este seguidor consta de dos bloques principales: la tarjeta controladora y la parte mecánica. Su diseño se basó en el uso de fotorresistencias, microcontroladores y motores de pasos, el mismo posee altas prestaciones y bajo costo. El prototipo construido es utilizado en las investigaciones de aprovechamiento de la energía solar que se realizan en el Grupo de Energía Renovable Aplicadas (GERA de la Universidad de Oriente, particularmente en los paneles fotovoltaicos y los calentadores de agua. Se realizó una prueba experimental en los laboratorios y en el polígono de dicho grupo y se comprobó que el seguidor solar funciona adecuadamente, cumpliendo con las expectativas deseadas.The design and implementation of a device for obtaining the coordinates of the sun at any time during the day, it means, a solar tracker of type two axis by luminous point is developed in this paper. This tracker consists of two main blocks: the controller board and the mechanical part. The design is based on the use of photoresistences, microcontrollers and stepper motors. The prototype is used on investigations about solar energy developed at the GERA (Grupo de Energía Renovable Aplicada of Universidad de Oriente, particularly in photovoltaic panels and water heaters. An experimental test was conducted in the laboratories and at the site of the group and it was found that the solar tracker is functioning properly, meeting the desired expectations.

  6. Solar Adaptive Optics

    Directory of Open Access Journals (Sweden)

    Thomas R. Rimmele

    2011-06-01

    Full Text Available Adaptive optics (AO has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO and Ground-Layer AO (GLAO will be given.

  7. Solar Adaptive Optics.

    Science.gov (United States)

    Rimmele, Thomas R; Marino, Jose

    Adaptive optics (AO) has become an indispensable tool at ground-based solar telescopes. AO enables the ground-based observer to overcome the adverse effects of atmospheric seeing and obtain diffraction limited observations. Over the last decade adaptive optics systems have been deployed at major ground-based solar telescopes and revitalized ground-based solar astronomy. The relatively small aperture of solar telescopes and the bright source make solar AO possible for visible wavelengths where the majority of solar observations are still performed. Solar AO systems enable diffraction limited observations of the Sun for a significant fraction of the available observing time at ground-based solar telescopes, which often have a larger aperture than equivalent space based observatories, such as HINODE. New ground breaking scientific results have been achieved with solar adaptive optics and this trend continues. New large aperture telescopes are currently being deployed or are under construction. With the aid of solar AO these telescopes will obtain observations of the highly structured and dynamic solar atmosphere with unprecedented resolution. This paper reviews solar adaptive optics techniques and summarizes the recent progress in the field of solar adaptive optics. An outlook to future solar AO developments, including a discussion of Multi-Conjugate AO (MCAO) and Ground-Layer AO (GLAO) will be given. Supplementary material is available for this article at 10.12942/lrsp-2011-2.

  8. Principles of solar engineering

    CERN Document Server

    Goswami, D Yogi

    2015-01-01

    Introduction to Solar Energy ConversionGlobal Energy Needs and ResourcesSolar EnergyEnergy StorageEconomics of Solar SystemsSummary of RE ResourcesForecast of Future Energy MixReferencesFundamentals of Solar RadiationThe Physics of the Sun and Its Energy TransportThermal Radiation FundamentalsSun-Earth Geometric RelationshipSolar RadiationEstimation of Terrestrial Solar RadiationModels Based on Long-Term Measured Horizontal Solar RadiationMeasurement of Solar RadiationSolar Radiation Mapping Using Satellite DataReferencesSuggested ReadingsSolar Thermal CollectorsRadiative Properties and Characteristics of MaterialsFlat-Plate CollectorsTubular Solar Energy CollectorsExperimental Testing of CollectorsConcentrating Solar CollectorsParabolic Trough ConcentratorCompound-Curvature Solar ConcentratorsCentral Receiver CollectorFresnel Reflectors and LensesSolar Concentrator SummaryReferencesSuggested ReadingThermal Energy Storage and TransportThermal Energy StorageTypes of TESDesign of Storage SystemEnergy Transport ...

  9. Introduction to solar cell production

    International Nuclear Information System (INIS)

    Kim, Gyeong Hae; Lee, Jun Sin

    2009-08-01

    This book introduces solar cell production. It is made up eight chapters, which are summary of solar cell with structure and prospect of the business, special variable of solar cell on light of the sun and factor causing variable of solar cell, production of solar cell with surface texturing, diffusion, metal printing dry and firing and edge isolation, process of solar cell on silicone wafer for solar cell, forming of electrodes, introduction of thin film solar cell on operating of solar cell, process of production and high efficiency of thin film solar cell, sorting of solar cell and production with background of silicone solar cell and thin film solar cell, structure and production of thin film solar cell and compound solar cell, introduction of solar cell module and the Industrial condition and prospect of solar cell.

  10. Evaluating Temporal Consistency in Marine Biodiversity Hotspots.

    Science.gov (United States)

    Piacenza, Susan E; Thurman, Lindsey L; Barner, Allison K; Benkwitt, Cassandra E; Boersma, Kate S; Cerny-Chipman, Elizabeth B; Ingeman, Kurt E; Kindinger, Tye L; Lindsley, Amy J; Nelson, Jake; Reimer, Jessica N; Rowe, Jennifer C; Shen, Chenchen; Thompson, Kevin A; Heppell, Selina S

    2015-01-01

    With the ongoing crisis of biodiversity loss and limited resources for conservation, the concept of biodiversity hotspots has been useful in determining conservation priority areas. However, there has been limited research into how temporal variability in biodiversity may influence conservation area prioritization. To address this information gap, we present an approach to evaluate the temporal consistency of biodiversity hotspots in large marine ecosystems. Using a large scale, public monitoring dataset collected over an eight year period off the US Pacific Coast, we developed a methodological approach for avoiding biases associated with hotspot delineation. We aggregated benthic fish species data from research trawls and calculated mean hotspot thresholds for fish species richness and Shannon's diversity indices over the eight year dataset. We used a spatial frequency distribution method to assign hotspot designations to the grid cells annually. We found no areas containing consistently high biodiversity through the entire study period based on the mean thresholds, and no grid cell was designated as a hotspot for greater than 50% of the time-series. To test if our approach was sensitive to sampling effort and the geographic extent of the survey, we followed a similar routine for the northern region of the survey area. Our finding of low consistency in benthic fish biodiversity hotspots over time was upheld, regardless of biodiversity metric used, whether thresholds were calculated per year or across all years, or the spatial extent for which we calculated thresholds and identified hotspots. Our results suggest that static measures of benthic fish biodiversity off the US West Coast are insufficient for identification of hotspots and that long-term data are required to appropriately identify patterns of high temporal variability in biodiversity for these highly mobile taxa. Given that ecological communities are responding to a changing climate and other

  11. Self-consistent gravitational self-force

    International Nuclear Information System (INIS)

    Pound, Adam

    2010-01-01

    I review the problem of motion for small bodies in general relativity, with an emphasis on developing a self-consistent treatment of the gravitational self-force. An analysis of the various derivations extant in the literature leads me to formulate an asymptotic expansion in which the metric is expanded while a representative worldline is held fixed. I discuss the utility of this expansion for both exact point particles and asymptotically small bodies, contrasting it with a regular expansion in which both the metric and the worldline are expanded. Based on these preliminary analyses, I present a general method of deriving self-consistent equations of motion for arbitrarily structured (sufficiently compact) small bodies. My method utilizes two expansions: an inner expansion that keeps the size of the body fixed, and an outer expansion that lets the body shrink while holding its worldline fixed. By imposing the Lorenz gauge, I express the global solution to the Einstein equation in the outer expansion in terms of an integral over a worldtube of small radius surrounding the body. Appropriate boundary data on the tube are determined from a local-in-space expansion in a buffer region where both the inner and outer expansions are valid. This buffer-region expansion also results in an expression for the self-force in terms of irreducible pieces of the metric perturbation on the worldline. Based on the global solution, these pieces of the perturbation can be written in terms of a tail integral over the body's past history. This approach can be applied at any order to obtain a self-consistent approximation that is valid on long time scales, both near and far from the small body. I conclude by discussing possible extensions of my method and comparing it to alternative approaches.

  12. Consistency Checking of Web Service Contracts

    DEFF Research Database (Denmark)

    Cambronero, M. Emilia; Okika, Joseph C.; Ravn, Anders Peter

    2008-01-01

    Behavioural properties are analyzed for web service contracts formulated in Business Process Execution Language (BPEL) and Choreography Description Language (CDL). The key result reported is an automated technique to check consistency between protocol aspects of the contracts. The contracts...... are abstracted to (timed) automata and from there a simulation is set up, which is checked using automated tools for analyzing networks of finite state processes. Here we use the Concurrency Work Bench. The proposed techniques are illustrated with a case study that include otherwise difficult to analyze fault...

  13. A method for consistent precision radiation therapy

    International Nuclear Information System (INIS)

    Leong, J.

    1985-01-01

    Using a meticulous setup procedure in which repeated portal films were taken before each treatment until satisfactory portal verifications were obtained, a high degree of precision in patient positioning was achieved. A fluctuation from treatment to treatment, over 11 treatments, of less than +-0.10 cm (S.D.) for anatomical points inside the treatment field was obtained. This, however, only applies to specific anatomical points selected for this positioning procedure and does not apply to all points within the portal. We have generalized this procedure and have suggested a means by which any target volume can be consistently positioned which may approach this degree of precision. (orig.)

  14. Gentzen's centenary the quest for consistency

    CERN Document Server

    Rathjen, Michael

    2015-01-01

    Gerhard Gentzen has been described as logic’s lost genius, whom Gödel called a better logician than himself. This work comprises articles by leading proof theorists, attesting to Gentzen’s enduring legacy to mathematical logic and beyond. The contributions range from philosophical reflections and re-evaluations of Gentzen’s original consistency proofs to the most recent developments in proof theory. Gentzen founded modern proof theory. His sequent calculus and natural deduction system beautifully explain the deep symmetries of logic. They underlie modern developments in computer science such as automated theorem proving and type theory.

  15. Two consistent calculations of the Weinberg angle

    International Nuclear Information System (INIS)

    Fairlie, D.B.

    1979-01-01

    The Weinberg-Salam theory is reformulated as a pure Yang-Mills theory in a six-dimensional space, the Higgs field being interpreted as gauge potentials in the additional dimensions. Viewed in this way, the condition that the Higgs field transforms as a U(1) representation of charge one is equivalent to requiring a value of 30 0 C for the Weinberg angle. A second consistent determination comes from the idea borrowed from monopole theory that the electromagnetic field is in the direction of the Higgs field. (Author)

  16. Golden Rays - July 2017 | Solar Research | Solar Research | NREL

    Science.gov (United States)

    , subscribe to the Solar Newsletter. SUBSCRIBE Hot Topics Two solar installers secure solar panels on the roof that has the potential to improve the efficiency of solar panels while leveraging existing

  17. SOLAR AIRCRAFT DESIGN

    OpenAIRE

    RAHMATI, Sadegh; GHASED, Amir

    2015-01-01

    Abstract. Generally domain Aircraft uses conventional fuel. These fuel having limited life, high cost and pollutant. Also nowadays price of petrol and other fuels are going to be higher, because of scarcity of those fuels. So there is great demand of use of non-exhaustible unlimited source of energy like solar energy. Solar aircraft is one of the ways to utilize solar energy. Solar aircraft uses solar panel to collect the solar radiation for immediate use but it also store the remaining part ...

  18. Consistent resolution of some relativistic quantum paradoxes

    International Nuclear Information System (INIS)

    Griffiths, Robert B.

    2002-01-01

    A relativistic version of the (consistent or decoherent) histories approach to quantum theory is developed on the basis of earlier work by Hartle, and used to discuss relativistic forms of the paradoxes of spherical wave packet collapse, Bohm's formulation of the Einstein-Podolsky-Rosen paradox, and Hardy's paradox. It is argued that wave function collapse is not needed for introducing probabilities into relativistic quantum mechanics, and in any case should never be thought of as a physical process. Alternative approaches to stochastic time dependence can be used to construct a physical picture of the measurement process that is less misleading than collapse models. In particular, one can employ a coarse-grained but fully quantum-mechanical description in which particles move along trajectories, with behavior under Lorentz transformations the same as in classical relativistic physics, and detectors are triggered by particles reaching them along such trajectories. States entangled between spacelike separate regions are also legitimate quantum descriptions, and can be consistently handled by the formalism presented here. The paradoxes in question arise because of using modes of reasoning which, while correct for classical physics, are inconsistent with the mathematical structure of quantum theory, and are resolved (or tamed) by using a proper quantum analysis. In particular, there is no need to invoke, nor any evidence for, mysterious long-range superluminal influences, and thus no incompatibility, at least from this source, between relativity theory and quantum mechanics

  19. Self-consistent model of confinement

    International Nuclear Information System (INIS)

    Swift, A.R.

    1988-01-01

    A model of the large-spatial-distance, zero--three-momentum, limit of QCD is developed from the hypothesis that there is an infrared singularity. Single quarks and gluons do not propagate because they have infinite energy after renormalization. The Hamiltonian formulation of the path integral is used to quantize QCD with physical, nonpropagating fields. Perturbation theory in the infrared limit is simplified by the absence of self-energy insertions and by the suppression of large classes of diagrams due to vanishing propagators. Remaining terms in the perturbation series are resummed to produce a set of nonlinear, renormalizable integral equations which fix both the confining interaction and the physical propagators. Solutions demonstrate the self-consistency of the concepts of an infrared singularity and nonpropagating fields. The Wilson loop is calculated to provide a general proof of confinement. Bethe-Salpeter equations for quark-antiquark pairs and for two gluons have finite-energy solutions in the color-singlet channel. The choice of gauge is addressed in detail. Large classes of corrections to the model are discussed and shown to support self-consistency

  20. Subgame consistent cooperation a comprehensive treatise

    CERN Document Server

    Yeung, David W K

    2016-01-01

    Strategic behavior in the human and social world has been increasingly recognized in theory and practice. It is well known that non-cooperative behavior could lead to suboptimal or even highly undesirable outcomes. Cooperation suggests the possibility of obtaining socially optimal solutions and the calls for cooperation are prevalent in real-life problems. Dynamic cooperation cannot be sustainable if there is no guarantee that the agreed upon optimality principle at the beginning is maintained throughout the cooperation duration. It is due to the lack of this kind of guarantees that cooperative schemes fail to last till its end or even fail to get started. The property of subgame consistency in cooperative dynamic games and the corresponding solution mechanism resolve this “classic” problem in game theory. This book is a comprehensive treatise on subgame consistent dynamic cooperation covering the up-to-date state of the art analyses in this important topic. It sets out to provide the theory, solution tec...

  1. Sludge characterization: the role of physical consistency

    Energy Technology Data Exchange (ETDEWEB)

    Spinosa, Ludovico; Wichmann, Knut

    2003-07-01

    The physical consistency is an important parameter in sewage sludge characterization as it strongly affects almost all treatment, utilization and disposal operations. In addition, in many european Directives a reference to the physical consistency is reported as a characteristic to be evaluated for fulfilling the regulations requirements. Further, in many analytical methods for sludge different procedures are indicated depending on whether a sample is liquid or not, is solid or not. Three physical behaviours (liquid, paste-like and solid) can be observed with sludges, so the development of analytical procedures to define the boundary limit between liquid and paste-like behaviours (flowability) and that between solid and paste-like ones (solidity) is of growing interest. Several devices can be used for evaluating the flowability and solidity properties, but often they are costly and difficult to be operated in the field. Tests have been carried out to evaluate the possibility to adopt a simple extrusion procedure for flowability measurements, and a Vicat needle for solidity ones. (author)

  2. Consistent mutational paths predict eukaryotic thermostability

    Directory of Open Access Journals (Sweden)

    van Noort Vera

    2013-01-01

    Full Text Available Abstract Background Proteomes of thermophilic prokaryotes have been instrumental in structural biology and successfully exploited in biotechnology, however many proteins required for eukaryotic cell function are absent from bacteria or archaea. With Chaetomium thermophilum, Thielavia terrestris and Thielavia heterothallica three genome sequences of thermophilic eukaryotes have been published. Results Studying the genomes and proteomes of these thermophilic fungi, we found common strategies of thermal adaptation across the different kingdoms of Life, including amino acid biases and a reduced genome size. A phylogenetics-guided comparison of thermophilic proteomes with those of other, mesophilic Sordariomycetes revealed consistent amino acid substitutions associated to thermophily that were also present in an independent lineage of thermophilic fungi. The most consistent pattern is the substitution of lysine by arginine, which we could find in almost all lineages but has not been extensively used in protein stability engineering. By exploiting mutational paths towards the thermophiles, we could predict particular amino acid residues in individual proteins that contribute to thermostability and validated some of them experimentally. By determining the three-dimensional structure of an exemplar protein from C. thermophilum (Arx1, we could also characterise the molecular consequences of some of these mutations. Conclusions The comparative analysis of these three genomes not only enhances our understanding of the evolution of thermophily, but also provides new ways to engineer protein stability.

  3. Consistency of extreme flood estimation approaches

    Science.gov (United States)

    Felder, Guido; Paquet, Emmanuel; Penot, David; Zischg, Andreas; Weingartner, Rolf

    2017-04-01

    Estimations of low-probability flood events are frequently used for the planning of infrastructure as well as for determining the dimensions of flood protection measures. There are several well-established methodical procedures to estimate low-probability floods. However, a global assessment of the consistency of these methods is difficult to achieve, the "true value" of an extreme flood being not observable. Anyway, a detailed comparison performed on a given case study brings useful information about the statistical and hydrological processes involved in different methods. In this study, the following three different approaches for estimating low-probability floods are compared: a purely statistical approach (ordinary extreme value statistics), a statistical approach based on stochastic rainfall-runoff simulation (SCHADEX method), and a deterministic approach (physically based PMF estimation). These methods are tested for two different Swiss catchments. The results and some intermediate variables are used for assessing potential strengths and weaknesses of each method, as well as for evaluating the consistency of these methods.

  4. Consistent biokinetic models for the actinide elements

    International Nuclear Information System (INIS)

    Leggett, R.W.

    2001-01-01

    The biokinetic models for Th, Np, Pu, Am and Cm currently recommended by the International Commission on Radiological Protection (ICRP) were developed within a generic framework that depicts gradual burial of skeletal activity in bone volume, depicts recycling of activity released to blood and links excretion to retention and translocation of activity. For other actinide elements such as Ac, Pa, Bk, Cf and Es, the ICRP still uses simplistic retention models that assign all skeletal activity to bone surface and depicts one-directional flow of activity from blood to long-term depositories to excreta. This mixture of updated and older models in ICRP documents has led to inconsistencies in dose estimates and interpretation of bioassay for radionuclides with reasonably similar biokinetics. This paper proposes new biokinetic models for Ac, Pa, Bk, Cf and Es that are consistent with the updated models for Th, Np, Pu, Am and Cm. The proposed models are developed within the ICRP's generic model framework for bone-surface-seeking radionuclides, and an effort has been made to develop parameter values that are consistent with results of comparative biokinetic data on the different actinide elements. (author)

  5. Solar-wind predictions for the Parker Solar Probe orbit. Near-Sun extrapolations derived from an empirical solar-wind model based on Helios and OMNI observations

    Science.gov (United States)

    Venzmer, M. S.; Bothmer, V.

    2018-03-01

    Context. The Parker Solar Probe (PSP; formerly Solar Probe Plus) mission will be humanitys first in situ exploration of the solar corona with closest perihelia at 9.86 solar radii (R⊙) distance to the Sun. It will help answer hitherto unresolved questions on the heating of the solar corona and the source and acceleration of the solar wind and solar energetic particles. The scope of this study is to model the solar-wind environment for PSPs unprecedented distances in its prime mission phase during the years 2018 to 2025. The study is performed within the Coronagraphic German And US SolarProbePlus Survey (CGAUSS) which is the German contribution to the PSP mission as part of the Wide-field Imager for Solar PRobe. Aim. We present an empirical solar-wind model for the inner heliosphere which is derived from OMNI and Helios data. The German-US space probes Helios 1 and Helios 2 flew in the 1970s and observed solar wind in the ecliptic within heliocentric distances of 0.29 au to 0.98 au. The OMNI database consists of multi-spacecraft intercalibrated in situ data obtained near 1 au over more than five solar cycles. The international sunspot number (SSN) and its predictions are used to derive dependencies of the major solar-wind parameters on solar activity and to forecast their properties for the PSP mission. Methods: The frequency distributions for the solar-wind key parameters, magnetic field strength, proton velocity, density, and temperature, are represented by lognormal functions. In addition, we consider the velocity distributions bi-componental shape, consisting of a slower and a faster part. Functional relations to solar activity are compiled with use of the OMNI data by correlating and fitting the frequency distributions with the SSN. Further, based on the combined data set from both Helios probes, the parameters frequency distributions are fitted with respect to solar distance to obtain power law dependencies. Thus an empirical solar-wind model for the inner

  6. 78 FR 17718 - Notice of Availability of the Record of Decision for the McCoy Solar Energy Project, Riverside...

    Science.gov (United States)

    2013-03-22

    ....LVRWB09B2510.FX0000] Notice of Availability of the Record of Decision for the McCoy Solar Energy Project... McCoy Solar Energy Project (MSEP), a photovoltaic solar electricity generation project. The Secretary of... proposed would have consisted of an up to 750-megawatt photovoltaic solar energy generation facility and...

  7. Solar array flight dynamic experiment

    Science.gov (United States)

    Schock, Richard W.

    1987-01-01

    The purpose of the Solar Array Flight Dynamic Experiment (SAFDE) is to demonstrate the feasibility of on-orbit measurement and ground processing of large space structures' dynamic characteristics. Test definition or verification provides the dynamic characteristic accuracy required for control systems use. An illumination/measurement system was developed to fly on space shuttle flight STS-41D. The system was designed to dynamically evaluate a large solar array called the Solar Array Flight Experiment (SAFE) that had been scheduled for this flight. The SAFDE system consisted of a set of laser diode illuminators, retroreflective targets, an intelligent star tracker receiver and the associated equipment to power, condition, and record the results. In six tests on STS-41D, data was successfully acquired from 18 retroreflector targets and ground processed, post flight, to define the solar array's dynamic characteristic. The flight experiment proved the viability of on-orbit test definition of large space structures dynamic characteristics. Future large space structures controllability should be greatly enhanced by this capability.

  8. Solar cycle variations in mesospheric carbon monoxide

    Science.gov (United States)

    Lee, Jae N.; Wu, Dong L.; Ruzmaikin, Alexander; Fontenla, Juan

    2018-05-01

    As an extension of Lee et al. (2013), solar cycle variation of carbon monoxide (CO) is analyzed with MLS observation, which covers more than thirteen years (2004-2017) including maximum of solar cycle 24. Being produced primarily by the carbon dioxide (CO2) photolysis in the lower thermosphere, the variations of the mesospheric CO concentration are largely driven by the solar cycle modulated ultraviolet (UV) variation. This solar signal extends down to the lower altitudes by the dynamical descent in the winter polar vortex, showing a time lag that is consistent with the average descent velocity. To characterize a global distribution of the solar impact, MLS CO is correlated with the SORCE measured total solar irradiance (TSI) and UV. As high as 0.8 in most of the polar mesosphere, the linear correlation coefficients between CO and UV/TSI are more robust than those found in the previous work. The photochemical contribution explains most (68%) of the total variance of CO while the dynamical contribution accounts for 21% of the total variance at upper mesosphere. The photochemistry driven CO anomaly signal is extended in the tropics by vertical mixing. The solar cycle signal in CO is further examined with the Whole Atmosphere Community Climate Model (WACCM) 3.5 simulation by implementing two different modeled Spectral Solar Irradiances (SSIs): SRPM 2012 and NRLSSI. The model simulations underestimate the mean CO amount and solar cycle variations of CO, by a factor of 3, compared to those obtained from MLS observation. Different inputs of the solar spectrum have small impacts on CO variation.

  9. Consistency of canonical formulation of Horava gravity

    International Nuclear Information System (INIS)

    Soo, Chopin

    2011-01-01

    Both the non-projectable and projectable version of Horava gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra graviton mode which can be problematic. A new formulation (based on arXiv:1007.1563) of Horava gravity which is naturally realized as a representation of the master constraint algebra (instead of the Dirac algebra) studied by loop quantum gravity researchers is presented. This formulation yields a consistent canonical theory with first class constraints; and captures the essence of Horava gravity in retaining only spatial diffeomorphisms as the physically relevant non-trivial gauge symmetry. At the same time the local Hamiltonian constraint is equivalently enforced by the master constraint.

  10. Consistency of canonical formulation of Horava gravity

    Energy Technology Data Exchange (ETDEWEB)

    Soo, Chopin, E-mail: cpsoo@mail.ncku.edu.tw [Department of Physics, National Cheng Kung University, Tainan, Taiwan (China)

    2011-09-22

    Both the non-projectable and projectable version of Horava gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra graviton mode which can be problematic. A new formulation (based on arXiv:1007.1563) of Horava gravity which is naturally realized as a representation of the master constraint algebra (instead of the Dirac algebra) studied by loop quantum gravity researchers is presented. This formulation yields a consistent canonical theory with first class constraints; and captures the essence of Horava gravity in retaining only spatial diffeomorphisms as the physically relevant non-trivial gauge symmetry. At the same time the local Hamiltonian constraint is equivalently enforced by the master constraint.

  11. A consistent thermodynamic database for cement minerals

    International Nuclear Information System (INIS)

    Blanc, P.; Claret, F.; Burnol, A.; Marty, N.; Gaboreau, S.; Tournassat, C.; Gaucher, E.C.; Giffault, E.; Bourbon, X.

    2010-01-01

    work - the formation enthalpy and the Cp(T) function are taken from the literature or estimated - finally, the Log K(T) function is calculated, based on the selected dataset and it is compared to experimental data gathered at different temperatures. Each experimental point is extracted from solution compositions by using PHREEQC with a selection of aqueous complexes, consistent with the Thermochimie database. The selection was tested namely by drawing activity diagrams, allowing to assess phases relations. An example of such a diagram, drawn in the CaO-Al 2 O 3 -SiO 2 -H 2 O system is displayed. It can be seen that low pH concrete alteration proceeds essentially in decreasing the C/S ratio in C-S-H phases to the point where C-S-H are no longer stable and replaced by zeolite, then clay minerals. This evolution corresponds to a decrease in silica activity, which is consistent with the pH decrease, as silica concentration depends essentially on pH. Some rather consistent phase relations have been obtained for the SO 3 -Al 2 O 3 -CaO-CO 2 -H 2 O system. Addition of iron III enlarges the AFm-SO 4 stability field to the low temperature domain, whereas it decreases the pH domain where ettringite is stable. On the other hand, the stability field of katoite remains largely ambiguous, namely with respect to a hydro-garnet/grossular solid solution. With respect to other databases this work was made in consistency with a larger mineral selection, so that it can be used for modelling works in the cement clay interaction context

  12. Evaluating the hydrological consistency of evaporation products

    KAUST Repository

    Lopez Valencia, Oliver Miguel; Houborg, Rasmus; McCabe, Matthew

    2017-01-01

    Advances in space-based observations have provided the capacity to develop regional- to global-scale estimates of evaporation, offering insights into this key component of the hydrological cycle. However, the evaluation of large-scale evaporation retrievals is not a straightforward task. While a number of studies have intercompared a range of these evaporation products by examining the variance amongst them, or by comparison of pixel-scale retrievals against ground-based observations, there is a need to explore more appropriate techniques to comprehensively evaluate remote-sensing-based estimates. One possible approach is to establish the level of product agreement between related hydrological components: for instance, how well do evaporation patterns and response match with precipitation or water storage changes? To assess the suitability of this "consistency"-based approach for evaluating evaporation products, we focused our investigation on four globally distributed basins in arid and semi-arid environments, comprising the Colorado River basin, Niger River basin, Aral Sea basin, and Lake Eyre basin. In an effort to assess retrieval quality, three satellite-based global evaporation products based on different methodologies and input data, including CSIRO-PML, the MODIS Global Evapotranspiration product (MOD16), and Global Land Evaporation: the Amsterdam Methodology (GLEAM), were evaluated against rainfall data from the Global Precipitation Climatology Project (GPCP) along with Gravity Recovery and Climate Experiment (GRACE) water storage anomalies. To ensure a fair comparison, we evaluated consistency using a degree correlation approach after transforming both evaporation and precipitation data into spherical harmonics. Overall we found no persistent hydrological consistency in these dryland environments. Indeed, the degree correlation showed oscillating values between periods of low and high water storage changes, with a phase difference of about 2–3 months

  13. Self-consistent modelling of ICRH

    International Nuclear Information System (INIS)

    Hellsten, T.; Hedin, J.; Johnson, T.; Laxaaback, M.; Tennfors, E.

    2001-01-01

    The performance of ICRH is often sensitive to the shape of the high energy part of the distribution functions of the resonating species. This requires self-consistent calculations of the distribution functions and the wave-field. In addition to the wave-particle interactions and Coulomb collisions the effects of the finite orbit width and the RF-induced spatial transport are found to be important. The inward drift dominates in general even for a symmetric toroidal wave spectrum in the centre of the plasma. An inward drift does not necessarily produce a more peaked heating profile. On the contrary, for low concentrations of hydrogen minority in deuterium plasmas it can even give rise to broader profiles. (author)

  14. Non linear self consistency of microtearing modes

    International Nuclear Information System (INIS)

    Garbet, X.; Mourgues, F.; Samain, A.

    1987-01-01

    The self consistency of a microtearing turbulence is studied in non linear regimes where the ergodicity of the flux lines determines the electron response. The current which sustains the magnetic perturbation via the Ampere law results from the combines action of the radial electric field in the frame where the island chains are static and of the thermal electron diamagnetism. Numerical calculations show that at usual values of β pol in Tokamaks the turbulence can create a diffusion coefficient of order ν th p 2 i where p i is the ion larmor radius and ν th the electron ion collision frequency. On the other hand, collisionless regimes involving special profiles of each mode near the resonant surface seem possible

  15. Consistent evolution in a pedestrian flow

    Science.gov (United States)

    Guan, Junbiao; Wang, Kaihua

    2016-03-01

    In this paper, pedestrian evacuation considering different human behaviors is studied by using a cellular automaton (CA) model combined with the snowdrift game theory. The evacuees are divided into two types, i.e. cooperators and defectors, and two different human behaviors, herding behavior and independent behavior, are investigated. It is found from a large amount of numerical simulations that the ratios of the corresponding evacuee clusters are evolved to consistent states despite 11 typically different initial conditions, which may largely owe to self-organization effect. Moreover, an appropriate proportion of initial defectors who are of herding behavior, coupled with an appropriate proportion of initial defectors who are of rationally independent thinking, are two necessary factors for short evacuation time.

  16. Evaluating the hydrological consistency of evaporation products

    KAUST Repository

    Lopez Valencia, Oliver Miguel

    2017-01-18

    Advances in space-based observations have provided the capacity to develop regional- to global-scale estimates of evaporation, offering insights into this key component of the hydrological cycle. However, the evaluation of large-scale evaporation retrievals is not a straightforward task. While a number of studies have intercompared a range of these evaporation products by examining the variance amongst them, or by comparison of pixel-scale retrievals against ground-based observations, there is a need to explore more appropriate techniques to comprehensively evaluate remote-sensing-based estimates. One possible approach is to establish the level of product agreement between related hydrological components: for instance, how well do evaporation patterns and response match with precipitation or water storage changes? To assess the suitability of this "consistency"-based approach for evaluating evaporation products, we focused our investigation on four globally distributed basins in arid and semi-arid environments, comprising the Colorado River basin, Niger River basin, Aral Sea basin, and Lake Eyre basin. In an effort to assess retrieval quality, three satellite-based global evaporation products based on different methodologies and input data, including CSIRO-PML, the MODIS Global Evapotranspiration product (MOD16), and Global Land Evaporation: the Amsterdam Methodology (GLEAM), were evaluated against rainfall data from the Global Precipitation Climatology Project (GPCP) along with Gravity Recovery and Climate Experiment (GRACE) water storage anomalies. To ensure a fair comparison, we evaluated consistency using a degree correlation approach after transforming both evaporation and precipitation data into spherical harmonics. Overall we found no persistent hydrological consistency in these dryland environments. Indeed, the degree correlation showed oscillating values between periods of low and high water storage changes, with a phase difference of about 2–3 months

  17. Internally consistent gamma ray burst time history phenomenology

    International Nuclear Information System (INIS)

    Cline, T.L.

    1985-01-01

    A phenomenology for gamma ray burst time histories is outlined. Order of their generally chaotic appearance is attempted, based on the speculation that any one burst event can be represented above 150 keV as a superposition of similarly shaped increases of varying intensity. The increases can generally overlap, however, confusing the picture, but a given event must at least exhibit its own limiting characteristic rise and decay times if the measurements are made with instruments having adequate temporal resolution. Most catalogued observations may be of doubtful or marginal utility to test this hypothesis, but some time histories from Helios-2, Pioneer Venus Orbiter and other instruments having one-to several-millisecond capabilities appear to provide consistency. Also, recent studies of temporally resolved Solar Maximum Mission burst energy spectra are entirely compatible with this picture. The phenomenology suggested here, if correct, may assist as an analytic tool for modelling of burst processes and possibly in the definition of burst source populations

  18. Distribution of mass in the planetary system and solar nebulae

    Energy Technology Data Exchange (ETDEWEB)

    Weidenschilling, S J [Carnegie Institution of Washington, D.C. (USA). Dept. of Terrestrial Magnetism

    1977-09-01

    A model 'solar nebula' is constructed by adding the solar complement of light elements to each planet, using recent models of planetary compositions. Uncertainties in this approach are estimated. The computed surface density varies approximately as rsup(-3/2). Mercury, Mars and the asteroid belt are anomalously low in mass, but processes exist which would preferentially remove matter from these regions. Planetary masses and compositions are generally consistent with a monotonic density distribution in the primordial solar nebula.

  19. Solar + Storage Synergies for Managing Commercial-Customer Demand Charges

    Energy Technology Data Exchange (ETDEWEB)

    Gagnon, Pieter J. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Govindarajan, Anand [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Bird, Lori A. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-10-24

    We study the synergies between behind-the-meter solar and storage in reducing commercial-customer demand charges. This follows two previous studies that examined demand charge savings for stand-alone solar in both the residential and commercial sectors. In this study we show that solar and storage show consistent synergies for demand charge management, that the magnitude of reductions are highly customer-specific, and that the magnitude of savings is influenced by the design of the electricity tariff.

  20. Thermodynamically consistent model calibration in chemical kinetics

    Directory of Open Access Journals (Sweden)

    Goutsias John

    2011-05-01

    Full Text Available Abstract Background The dynamics of biochemical reaction systems are constrained by the fundamental laws of thermodynamics, which impose well-defined relationships among the reaction rate constants characterizing these systems. Constructing biochemical reaction systems from experimental observations often leads to parameter values that do not satisfy the necessary thermodynamic constraints. This can result in models that are not physically realizable and may lead to inaccurate, or even erroneous, descriptions of cellular function. Results We introduce a thermodynamically consistent model calibration (TCMC method that can be effectively used to provide thermodynamically feasible values for the parameters of an open biochemical reaction system. The proposed method formulates the model calibration problem as a constrained optimization problem that takes thermodynamic constraints (and, if desired, additional non-thermodynamic constraints into account. By calculating thermodynamically feasible values for the kinetic parameters of a well-known model of the EGF/ERK signaling cascade, we demonstrate the qualitative and quantitative significance of imposing thermodynamic constraints on these parameters and the effectiveness of our method for accomplishing this important task. MATLAB software, using the Systems Biology Toolbox 2.1, can be accessed from http://www.cis.jhu.edu/~goutsias/CSS lab/software.html. An SBML file containing the thermodynamically feasible EGF/ERK signaling cascade model can be found in the BioModels database. Conclusions TCMC is a simple and flexible method for obtaining physically plausible values for the kinetic parameters of open biochemical reaction systems. It can be effectively used to recalculate a thermodynamically consistent set of parameter values for existing thermodynamically infeasible biochemical reaction models of cellular function as well as to estimate thermodynamically feasible values for the parameters of new

  1. Coupling of Luminescent Solar Concentrators to Plasmonic Solar Cells

    Science.gov (United States)

    Wang, Shu-Yi

    To make inexpensive solar cells is a continuous goal for solar photovoltaic (PV) energy industry. Thin film solar cells of various materials have been developed and continue to emerge in order to replace bulk silicon solar cells. A thin film solar cell not only uses less material but also requires a less expensive refinery process. In addition, other advantages coming along with small thickness are higher open circuit voltage and higher conversion efficiency. However, thin film solar cells, especially those made of silicon, have significant optical losses. In order to address this problem, this thesis investigates the spectral coupling of thin films PV to luminescent solar concentrators (LSC). LSC are passive devices, consisting of plastic sheets embedded with fluorescent dyes which absorb part of the incoming radiation spectrum and emit at specific wavelength. The emitted light is concentrated by total internal reflection to the edge of the sheet, where the PVs are placed. Since the light emitted from the LSC edge is usually in a narrow spectral range, it is possible to employ diverse strategies to enhance PV absorption at the peak of the emission wavelength. Employing plasmonic nanostructures has been shown to enhance absorption of thin films via forward scattering, diffraction and localized surface plasmon. These two strategies are theoretically investigated here for improving the absorption and elevating the output power of a thin film solar cell. First, the idea of spectral coupling of luminescent solar concentrators to plasmonic solar cells is introduced to assess its potential for increasing the power output. This study is carried out employing P3HT/PC60BM organic solar cells and LSC with Lumogen Red dyes. A simplified spectral coupling analysis is employed to predict the power density, considering the output spectrum of the LSC equivalent to the emission spectrum of the dye and neglecting any angular dependence. Plasmonic tuning is conducted to enhance

  2. Solar Resource Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Renne, D.; George, R.; Wilcox, S.; Stoffel, T.; Myers, D.; Heimiller, D.

    2008-02-01

    This report covers the solar resource assessment aspects of the Renewable Systems Interconnection study. The status of solar resource assessment in the United States is described, and summaries of the availability of modeled data sets are provided.

  3. Solar engineering 1994

    International Nuclear Information System (INIS)

    Klett, D.E.; Hogan, R.E.; Tanaka, Tadayoshi

    1994-01-01

    This volume of 83 papers constitutes the Proceedings of the 1994 International Solar Energy Conference held March 27--30, 1994 in San Francisco, California. The Conference was jointly sponsored by the Solar Energy Division of the American Society of Mechanical Engineers, The Japan Society of Mechanical Engineers and the Japan Solar Energy Society. This is the fourth cooperation between ASME, JSME and JSES in cosponsoring the International Solar Energy Conference. The papers cover a wide range of solar technologies from low temperature solar ponds and desalinization to high temperature concentrators for space applications and central receivers for terrestrial power generation. Other topics covered include solar detoxification of hazardous waste, dish Stirling systems, solar cooling, photovoltaics, building energy analysis and conservation, simulation, and testing and measurement techniques. All papers were indexed separately for the data base

  4. Solar renovation demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Bruun Joergensen, O [ed.

    1998-10-01

    In the framework of the IEA SHC Programme, a Task on building renovation was initiated, `Task 20, Solar Energy in Building Renovation`. In a part of the task, Subtask C `Design of Solar Renovation Projects`, different solar renovation demonstration projects were developed. The objective of Subtask C was to demonstrate the application of advanced solar renovation concepts on real buildings. This report documents 16 different solar renovation demonstration projects including the design processes of the projects. The projects include the renovation of houses, schools, laboratories, and factories. Several solar techniques were used: building integrated solar collectors, glazed balconies, ventilated solar walls, transparent insulation, second skin facades, daylight elements and photovoltaic systems. These techniques are used in several simple as well as more complex system designs. (au)

  5. Solar Indices - Sunspot Numbers

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  6. Solar ultraviolet hazards

    International Nuclear Information System (INIS)

    Azmah Ali

    1995-01-01

    The paper discussed the following subjects: the sources of ultraviolet radiation, solar ultraviolet radiation definition, effects of over exposure to solar ultraviolet radiation, exposure limits and radiation protection of this radiation

  7. Solar Indices - Plage Regions

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  8. solar thermal power systems advanced solar thermal technology project, advanced subsystems development

    Science.gov (United States)

    1979-01-01

    The preliminary design for a prototype small (20 kWe) solar thermal electric generating unit was completed, consisting of several subsystems. The concentrator and the receiver collect solar energy and a thermal buffer storage with a transport system is used to provide a partially smoothed heat input to the Stirling engine. A fossil-fuel combustor is included in the receiver designs to permit operation with partial or no solar insolation (hybrid). The engine converts the heat input into mechanical action that powers a generator. To obtain electric power on a large scale, multiple solar modules will be required to operate in parallel. The small solar electric power plant used as a baseline design will provide electricity at remote sites and small communities.

  9. Solar energy promises realized?

    International Nuclear Information System (INIS)

    Oudshoff, B.

    2010-01-01

    The US market for solar cells grew 36% in 2009. Thousands of new jobs were created, many millions are invested and new businesses see new opportunities. Optimism among investors, incentivising government policy and new technological developments all contribute to these positive developments. This article provides an update of the incentive measures and their effects and a brief overview of the three solar energy technologies: photovoltaic (PV), solar thermal and concentrated solar power (CSP) [nl

  10. Solar Energy Technician/Installer

    Science.gov (United States)

    Moore, Pam

    2007-01-01

    Solar power (also known as solar energy) is solar radiation emitted from the sun. Large panels that absorb the sun's energy as the sun beats down on them gather solar power. The energy in the rays can be used for heat (solar thermal energy) or converted to electricity (photovoltaic energy). Each solar energy project, from conception to…

  11. Solar Probe ANalyzer for Ions - Laboratory Performance

    Science.gov (United States)

    Livi, R.; Larson, D. E.; Kasper, J. C.; Korreck, K. E.; Whittlesey, P. L.

    2017-12-01

    The Parker Solar Probe (PSP) mission is a heliospheric satellite that will orbit the Sun closer than any prior mission to date with a perihelion of 35 solar radii (RS) and an aphelion of 10 RS. PSP includes the Solar Wind Electrons Alphas and Protons (SWEAP) instrument suite, which in turn consists of four instruments: the Solar Probe Cup (SPC) and three Solar Probe ANalyzers (SPAN) for ions and electrons. Together, this suite will take local measurements of particles and electromagnetic fields within the Sun's corona. SPAN-Ai has completed flight calibration and spacecraft integration and is set to be launched in July of 2018. The main mode of operation consists of an electrostatic analyzer (ESA) at its aperture followed by a Time-of-Flight section to measure the energy and mass per charge (m/q) of the ambient ions. SPAN-Ai's main objective is to measure solar wind ions within an energy range of 5 eV - 20 keV, a mass/q between 1-60 [amu/q] and a field of view of 2400x1200. Here we will show flight calibration results and performance.

  12. Thermal solar energy

    International Nuclear Information System (INIS)

    Gonzalez, J.C.; Leal C, H.

    1998-01-01

    Some relative aspects to the development and current state of thermal solar energy are summarized, so much at domestic level as international. To facilitate the criteria understanding as the size of the facilities in thermal solar systems, topics as availability of the solar resource and its interactions with the matter are included. Finally, some perspectives for the development of this energetic alternative are presented

  13. Solar tracking system

    Science.gov (United States)

    Okandan, Murat; Nielson, Gregory N.

    2016-07-12

    Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

  14. Solar Research | NREL

    Science.gov (United States)

    Research Photo of a city landscape with a sun in the background. Solar energy research at NREL includes photovoltaics, concentrating solar power, solar grid and systems integration, and market research and analysis. Photovoltaic Research Photo of a roof-mounted PV array on the NREL campus. NREL's

  15. Alternatives in solar energy

    Science.gov (United States)

    Schueler, D. G.

    1978-01-01

    Although solar energy has the potential of providing a significant source of clean and renewable energy for a variety of applications, it is expected to penetrate the nation's energy economy very slowly. The alternative solar energy technologies which employ direct collection and conversion of solar radiation as briefly described.

  16. Solar cell concentrating system

    International Nuclear Information System (INIS)

    Garg, H.P.; Sharma, V.K.; Agarwal, R.K.

    1986-11-01

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  17. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  18. Solar sail deployment experiment

    OpenAIRE

    Shimose, Shigeru; 下瀬 滋

    2006-01-01

    Solar Sail move by receiving momentum of photons in sunlight. This paper presents results of some Spin-Stabilized Solar Sail deployment experiment. ISAS has successfully deployed, for the first time in the world, the polyimide Solar Sail taking advantage of centrifugal force in space. Based on this result, the new deployment mechanism is being developed which retracts the 50 m diameter sail.

  19. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  20. Exploring the Consistent behavior of Information Services

    Directory of Open Access Journals (Sweden)

    Kapidakis Sarantos

    2016-01-01

    Full Text Available Computer services are normally assumed to work well all the time. This usually happens for crucial services like bank electronic services, but not necessarily so for others, that there is no commercial interest in their operation. In this work we examined the operation and the errors of information services and tried to find clues that will help predicting the consistency of the behavior and the quality of the harvesting, which is harder because of the transient conditions and the many services and the huge amount of harvested information. We found many unexpected situations. The services that always successfully satisfy a request may in fact return part of it. A significant part of the OAI services have ceased working while many other serves occasionally fail to respond. Some services fail in the same way each time, and we pronounce them dead, as we do not see a way to overcome that. Others also always, or sometimes fail, but not in the same way, and we hope that their behavior is affected by temporary factors, that may improve later on. We categorized the services into classes, to study their behavior in more detail.

  1. A Consistent Phylogenetic Backbone for the Fungi

    Science.gov (United States)

    Ebersberger, Ingo; de Matos Simoes, Ricardo; Kupczok, Anne; Gube, Matthias; Kothe, Erika; Voigt, Kerstin; von Haeseler, Arndt

    2012-01-01

    The kingdom of fungi provides model organisms for biotechnology, cell biology, genetics, and life sciences in general. Only when their phylogenetic relationships are stably resolved, can individual results from fungal research be integrated into a holistic picture of biology. However, and despite recent progress, many deep relationships within the fungi remain unclear. Here, we present the first phylogenomic study of an entire eukaryotic kingdom that uses a consistency criterion to strengthen phylogenetic conclusions. We reason that branches (splits) recovered with independent data and different tree reconstruction methods are likely to reflect true evolutionary relationships. Two complementary phylogenomic data sets based on 99 fungal genomes and 109 fungal expressed sequence tag (EST) sets analyzed with four different tree reconstruction methods shed light from different angles on the fungal tree of life. Eleven additional data sets address specifically the phylogenetic position of Blastocladiomycota, Ustilaginomycotina, and Dothideomycetes, respectively. The combined evidence from the resulting trees supports the deep-level stability of the fungal groups toward a comprehensive natural system of the fungi. In addition, our analysis reveals methodologically interesting aspects. Enrichment for EST encoded data—a common practice in phylogenomic analyses—introduces a strong bias toward slowly evolving and functionally correlated genes. Consequently, the generalization of phylogenomic data sets as collections of randomly selected genes cannot be taken for granted. A thorough characterization of the data to assess possible influences on the tree reconstruction should therefore become a standard in phylogenomic analyses. PMID:22114356

  2. [Consistent Declarative Memory with Depressive Symptomatology].

    Science.gov (United States)

    Botelho de Oliveira, Silvia; Flórez, Ruth Natalia Suárez; Caballero, Diego Andrés Vásquez

    2012-12-01

    Some studies have suggested that potentiated remembrance of negative events on people with depressive disorders seems to be an important factor in the etiology, course and maintenance of depression. Evaluate the emotional memory in people with and without depressive symptomatology by means of an audio-visual test. 73 university students were evaluated, male and female, between 18 and 40 years old, distributed in two groups: with depressive symptomatology (32) and without depressive symptomatology (40), using the Scale from the Center of Epidemiologic Studies for Depression (CES-D, English Abbreviation) and a cutting point of 20. There were not meaningful differences between free and voluntary recalls, with and without depressive symptomatology, in spite of the fact that both groups had granted a higher emotional value to the audio-visual test and that they had associated it with emotional sadness. People with depressive symptomatology did not exhibit the effect of mnemonic potentiation generally associated to the content of the emotional version of the test; therefore, the hypothesis of emotional consistency was not validated. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  3. Self consistent field theory of virus assembly

    Science.gov (United States)

    Li, Siyu; Orland, Henri; Zandi, Roya

    2018-04-01

    The ground state dominance approximation (GSDA) has been extensively used to study the assembly of viral shells. In this work we employ the self-consistent field theory (SCFT) to investigate the adsorption of RNA onto positively charged spherical viral shells and examine the conditions when GSDA does not apply and SCFT has to be used to obtain a reliable solution. We find that there are two regimes in which GSDA does work. First, when the genomic RNA length is long enough compared to the capsid radius, and second, when the interaction between the genome and capsid is so strong that the genome is basically localized next to the wall. We find that for the case in which RNA is more or less distributed uniformly in the shell, regardless of the length of RNA, GSDA is not a good approximation. We observe that as the polymer-shell interaction becomes stronger, the energy gap between the ground state and first excited state increases and thus GSDA becomes a better approximation. We also present our results corresponding to the genome persistence length obtained through the tangent-tangent correlation length and show that it is zero in case of GSDA but is equal to the inverse of the energy gap when using SCFT.

  4. Consistency based correlations for tailings consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Azam, S.; Paul, A.C. [Regina Univ., Regina, SK (Canada). Environmental Systems Engineering

    2010-07-01

    The extraction of oil, uranium, metals and mineral resources from the earth generates significant amounts of tailings slurry. The tailings are contained in a disposal area with perimeter dykes constructed from the coarser fraction of the slurry. There are many unique challenges pertaining to the management of the containment facilities for several decades beyond mine closure that are a result of the slow settling rates of the fines and the high standing toxic waters. Many tailings dam failures in different parts of the world have been reported to result in significant contaminant releases causing public concern over the conventional practice of tailings disposal. Therefore, in order to reduce and minimize the environmental footprint, the fluid tailings need to undergo efficient consolidation. This paper presented an investigation into the consolidation behaviour of tailings in conjunction with soil consistency that captured physicochemical interactions. The paper discussed the large strain consolidation behaviour (volume compressibility and hydraulic conductivity) of six fine-grained soil slurries based on published data. The paper provided background information on the study and presented the research methodology. The geotechnical index properties of the selected materials were also presented. The large strain consolidation, volume compressibility correlations, and hydraulic conductivity correlations were provided. It was concluded that the normalized void ratio best described volume compressibility whereas liquidity index best explained the hydraulic conductivity. 17 refs., 3 tabs., 4 figs.

  5. Consistency between GRUAN sondes, LBLRTM and IASI

    Directory of Open Access Journals (Sweden)

    X. Calbet

    2017-06-01

    Full Text Available Radiosonde soundings from the GCOS Reference Upper-Air Network (GRUAN data record are shown to be consistent with Infrared Atmospheric Sounding Instrument (IASI-measured radiances via LBLRTM (Line-By-Line Radiative Transfer Model in the part of the spectrum that is mostly affected by water vapour absorption in the upper troposphere (from 700 hPa up. This result is key for climate data records, since GRUAN, IASI and LBLRTM constitute reference measurements or a reference radiative transfer model in each of their fields. This is specially the case for night-time radiosonde measurements. Although the sample size is small (16 cases, daytime GRUAN radiosonde measurements seem to have a small dry bias of 2.5 % in absolute terms of relative humidity, located mainly in the upper troposphere, with respect to LBLRTM and IASI. Full metrological closure is not yet possible and will not be until collocation uncertainties are better characterized and a full uncertainty covariance matrix is clarified for GRUAN.

  6. Self-consistent nuclear energy systems

    International Nuclear Information System (INIS)

    Shimizu, A.; Fujiie, Y.

    1995-01-01

    A concept of self-consistent energy systems (SCNES) has been proposed as an ultimate goal of the nuclear energy system in the coming centuries. SCNES should realize a stable and unlimited energy supply without endangering the human race and the global environment. It is defined as a system that realizes at least the following four objectives simultaneously: (a) energy generation -attain high efficiency in the utilization of fission energy; (b) fuel production - secure inexhaustible energy source: breeding of fissile material with the breeding ratio greater than one and complete burning of transuranium through recycling; (c) burning of radionuclides - zero release of radionuclides from the system: complete burning of transuranium and elimination of radioactive fission products by neutron capture reactions through recycling; (d) system safety - achieve system safety both for the public and experts: eliminate criticality-related safety issues by using natural laws and simple logic. This paper describes the concept of SCNES and discusses the feasibility of the system. Both ''neutron balance'' and ''energbalance'' of the system are introduced as the necessary conditions to be satisfied at least by SCNES. Evaluations made so far indicate that both the neutron balance and the energy balance can be realized by fast reactors but not by thermal reactors. Concerning the system safety, two safety concepts: ''self controllability'' and ''self-terminability'' are introduced to eliminate the criticality-related safety issues in fast reactors. (author)

  7. Toward a consistent model for glass dissolution

    International Nuclear Information System (INIS)

    Strachan, D.M.; McGrail, B.P.; Bourcier, W.L.

    1994-01-01

    Understanding the process of glass dissolution in aqueous media has advanced significantly over the last 10 years through the efforts of many scientists around the world. Mathematical models describing the glass dissolution process have also advanced from simple empirical functions to structured models based on fundamental principles of physics, chemistry, and thermodynamics. Although borosilicate glass has been selected as the waste form for disposal of high-level wastes in at least 5 countries, there is no international consensus on the fundamental methodology for modeling glass dissolution that could be used in assessing the long term performance of waste glasses in a geologic repository setting. Each repository program is developing their own model and supporting experimental data. In this paper, we critically evaluate a selected set of these structured models and show that a consistent methodology for modeling glass dissolution processes is available. We also propose a strategy for a future coordinated effort to obtain the model input parameters that are needed for long-term performance assessments of glass in a geologic repository. (author) 4 figs., tabs., 75 refs

  8. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-02-01

    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  9. Radiocarbon evidence for low frequency solar oscillations

    International Nuclear Information System (INIS)

    Damon, P.E.; Jirikowic, I.

    1992-01-01

    From the spectrum of Δ 14 C variations attributed to solar activity modulation of cosmogenic isotope production, a long-period variation (the Hallstattzeit) of 2120±20 years was deduced with 93% statistical confidence. Although most Hallstattzeit harmonic overtones may be shape-related, two also behave as fundamentals: that of 212 years (Suess) and of 88 years (Gleissberg). These exceptional harmonic overtones modulate the 11-year Schwabe solar cycle determined from indices of sunspots. The Hallstattzeit period may be associated with dramatic secular changes in solar behavior. Sun-like stars exhibit quiet and active states consistent with such long-period secular variations. The climate impact of solar output changes may partially explain periods of rapid climate change such as the Little Ice Age associated with 14 C anomalies. (author) 9 tabs., 8 figs., 23 refs

  10. Triple junction polymer solar cells for photoelectrochemical water splitting

    NARCIS (Netherlands)

    Esiner, S.; Eersel, van H.; Wienk, M.M.; Janssen, R.A.J.

    2013-01-01

    A triple junction polymer solar cell in a novel 1 + 2 type configuration provides photoelectrochemical water splitting in its maximum power point at V ˜ 1.70 V with an estimated solar to hydrogen energy conversion efficiency of 3.1%. The triple junction cell consists of a wide bandgap front cell and

  11. Installation package for a solar heating and hot water system

    Science.gov (United States)

    1978-01-01

    Development and installation of two commercial solar heating and hot water systems are reported. The systems consist of the following subsystems: collector, storage, transport, hot water, auxiliary energy and controls. General guidelines are provided which may be utilized in development of detailed installation plans and specifications. In addition, operation, maintenance and repair of a solar heating and hot water system instructions are included.

  12. Diffuse Solar System Design and Utilization in Agriculture and ...

    African Journals Online (AJOL)

    Diffuse solar radiation is a component of total solar radiation that is good for low temperature grade heating. Since the portion of the scattered radiation from the sun, which consists of short and long waves, that reaches the earth is diffused, its utilization in Agriculture as this paper suggested, has multiple phase change ...

  13. 3D-Printed external light traps for solar cells

    NARCIS (Netherlands)

    van Dijk, L.; Paetzold, U.W.; Blab, Gerhard; Marcus, E.A.P.; Oostra, A.J.; van de Groep, J.; Polman, A.; Schropp, R.E.I.; Di Vece, M.

    2015-01-01

    We demonstrate a universally applicable 3D-printed external light trap for solar cells. We placed a macroscopic external light trap made of smoothened, silver coated plastic at the sun-facing surface of different types of solar cells. The trap consists of a reflective parabolic concentrator on top

  14. Front Cover: Solar RRL 3-4∕2017

    NARCIS (Netherlands)

    van Sark, W.G.J.H.M.; Moraitis, P.; Aalberts, Carlo; Drent, M.; Grasso, Thom; L'Ortye, Yves; Visscher, Marc; Westra, Mattijs; Plas, Rob; Planje, Wilco

    Luminescent solar concentrators consist of coloured plastic plates that concentrate sunlight to their sides where solar cells are mounted. Since their conception in the 1970s, novel dyes and nanocrystals have being developed for these concentrators, and it is time to show their full spectrum of

  15. Standard physics solution to the solar neutrino problem?

    Energy Technology Data Exchange (ETDEWEB)

    Dar, A [Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics

    1996-11-01

    The {sup 8}B solar neutrino flux predicted by the standard solar model (SSM) is consistent within the theoretical and experimental uncertainties with that at Kamiokande. The Gallium and Chlorine solar neutrino experiments, however, seem to imply that the {sup 7}Be solar neutrino flux is strongly suppressed compared with that predicted by the SSM. If the {sup 7}Be solar neutrino flux is suppressed, still it can be due to astrophysical effects not included in the simplistic SSM. Such effects include short term fluctuations or periodic variation of the temperature in the solar core, rotational mixing of {sup 3}He in the solar core, and dense plasma effects which may strongly enhance p-capture by {sup 7}Be relative to e-capture. The new generation of solar observations which already look non stop deep into the sun, like Superkamiokande through neutrinos, and SOHO and GONG through acoustic waves, may point at the correct solution. Only Superkamiokande and/or future solar neutrino experiments, such as SNO, BOREXINO and HELLAZ, will be able to find out whether the solar neutrino problem is caused by neutrino properties beyond the minimal standard electroweak model or whether it is just a problem of the too simplistic standard solar model. (author) 1 fig., 3 tabs., refs.

  16. Thermal performance of a transpired solar collector updraft tower

    International Nuclear Information System (INIS)

    Eryener, Dogan; Hollick, John; Kuscu, Hilmi

    2017-01-01

    Highlights: • Transpired solar collector updraft tower has been studied experimentally. • Transpired solar collector updraft tower efficiency ranges from 60 to 80%. • A comparison has been made with other SUT prototypes. • Three times higher efficiency compared to the glazed collectors of conventional solar towers. - Abstract: A novel solar updraft tower prototype, which consists of transpired solar collector, is studied, its function principle is described and its experimental thermal performance is presented for the first time. A test unit of transpired solar collector updraft tower was installed at the campus of Trakya University Engineering Faculty in Edirne-Turkey in 2014. Solar radiation, ambient temperature, collector cavity temperatures, and chimney velocities were monitored during summer and winter period. The results showed that transpired solar collector efficiency ranges from 60% to 80%. The maximum temperature rise in the collector area is found to be 16–18 °C on the typical sunny day. Compared to conventional solar tower glazed collectors, three times higher efficiency is obtained. With increased thermal efficiency, large solar collector areas for solar towers can be reduced in half or less.

  17. Solar Proton Events in Six Solar Cycles

    Science.gov (United States)

    Vitaly, Ishkov

    Based on materials the catalogs of solar proton events (SPE) in 1955 ‒ 2010 and list SPE for the current 24 solar cycle (SC) are examined confirmed SPE with E> 10 MeV proton flux in excess of 1 proton cm-2 s ster-1 (pfu) from Švestka and Simon’s (1955 - 1969) and 5 volumes Logachev’s (1970 - 2006) Catalogs of SPE. Historically thus it was formed, that the measurements of the proton fluxes began in the epoch “increased” solar activity (SC 18 ‒ 22), and includes transition period of the solar magnetic fields reconstruction from epoch “increased” to the epoch “lowered” solar activity (22 ‒ 23 SC). In current 24 SC ‒ first SC of the incipient epoch of “lowered” SA ‒ SPE realize under the new conditions, to that of previously not observed. As showed a study of five solar cycles with the reliable measurements of E> 10 MeV proton flux in excess of 1 pfu (1964 - 2013): ‒ a quantity of SPEs remained approximately identical in SC 20, 21, somewhat decreased in the initial solar cycle of the solar magnetic fields reconstruction period (22), but it returned to the same quantity in, the base for the period of reconstruction, SC 23. ‒ Into the first 5 years of the each solar cycle development the rate of the proton generation events noticeably increased in 22 cycles of solar activity and returned to the average in cycles 23 and 24. ‒ Extreme solar flare events are achieved, as a rule, in the solar magnetic fields reconstruction period (August - September 1859; June 1991; October ‒ November 2003.), it is confirmed also for SPE: the extreme fluxes of solar protons (S4) except one (August 1972) were occurred in period of perestroika (SC 22 and 23). This can speak, that inside the epochs SA, when the generation of magnetic field in the convective zone works in the steady-state regime, extreme SPE are improbable. ‒ The largest in the fluxes of protons (S3, S4) occur in the complexes of the active regions flare events, where magnetic field more

  18. View from Europe: stability, consistency or pragmatism

    International Nuclear Information System (INIS)

    Dunster, H.J.

    1988-01-01

    The last few years of this decade look like a period of reappraisal of radiation protection standards. The revised risk estimates from Japan will be available, and the United Nations Scientific Committee on the Effects of Atomic Radiation will be publishing new reports on biological topics. The International Commission on Radiological Protection (ICRP) has started a review of its basic recommendations, and the new specification for dose equivalent in radiation fields of the International Commission on Radiation Units and Measurements (ICRU) will be coming into use. All this is occurring at a time when some countries are still trying to catch up with committed dose equivalent and the recently recommended change in the value of the quality factor for neutrons. In Europe, the problems of adapting to new ICRP recommendations are considerable. The European Community, including 12 states and nine languages, takes ICRP recommendations as a basis and develops council directives that are binding on member states, which have then to arrange for their own regulatory changes. Any substantial adjustments could take 5 y or more to work through the system. Clearly, the regulatory preference is for stability. Equally clearly, trade unions and public interest groups favor a rapid response to scientific developments (provided that the change is downward). Organizations such as the ICRP have to balance their desire for internal consistency and intellectual purity against the practical problems of their clients in adjusting to change. This paper indicates some of the changes that might be necessary over the next few years and how, given a pragmatic approach, they might be accommodated in Europe without too much regulatory confusion

  19. The Consistency Between Clinical and Electrophysiological Diagnoses

    Directory of Open Access Journals (Sweden)

    Esra E. Okuyucu

    2009-09-01

    Full Text Available OBJECTIVE: The aim of this study was to provide information concerning the impact of electrophysiological tests in the clinical management and diagnosis of patients, and to evaluate the consistency between referring clinical diagnoses and electrophysiological diagnoses. METHODS: The study included 957 patients referred to the electroneuromyography (ENMG laboratory from different clinics with different clinical diagnoses in 2008. Demographic data, referring clinical diagnoses, the clinics where the requests wanted, and diagnoses after ENMG testing were recorded and statistically evaluated. RESULTS: In all, 957 patients [644 (67.3% female and 313 (32.7% male] were included in the study. Mean age of the patients was 45.40 ± 14.54 years. ENMG requests were made by different specialists; 578 (60.4% patients were referred by neurologists, 122 (12.8% by orthopedics, 140 (14.6% by neurosurgeons, and 117 (12.2% by physical treatment and rehabilitation departments. According to the results of ENMG testing, 513 (53.6% patients’ referrals were related to their referral diagnosis, whereas 397 (41.5% patients had normal ENMG test results, and 47 (4.9% patients had a diagnosis that differed from the referring diagnosis. Among the relation between the referral diagnosis and electrophysiological diagnosis according to the clinics where the requests were made, there was no statistical difference (p= 0.794, but there were statistically significant differences between the support of different clinical diagnoses, such as carpal tunnel syndrome, polyneuropathy, radiculopathy-plexopathy, entrapment neuropathy, and myopathy based on ENMG test results (p< 0.001. CONCLUSION: ENMG is a frequently used neurological examination. As such, referrals for ENMG can be made to either support the referring diagnosis or to exclude other diagnoses. This may explain the inconsistency between clinical referring diagnoses and diagnoses following ENMG

  20. Self-consistent meson mass spectrum

    International Nuclear Information System (INIS)

    Balazs, L.A.P.

    1982-01-01

    A dual-topological-unitarization (or dual-fragmentation) approach to the calculation of hadron masses is presented, in which the effect of planar ''sea''-quark loops is taken into account from the beginning. Using techniques based on analyticity and generalized ladder-graph dynamics, we first derive the approximate ''generic'' Regge-trajectory formula α(t) = max (S 1 +S 2 , S 3 +S 4 )-(1/2) +2alpha-circumflex'[s/sub a/ +(1/2)(t-summationm/sub i/ 2 )] for any given hadronic process 1+2→3+4, where S/sub i/ and m/sub i/ are the spins and masses of i = 1,2,3,4, and √s/sub a/ is the effective mass of the lowest nonvanishing contribution (a) exchanged in the crossed channel. By requiring a minimization of secondary (background, etc.) contributions to a, and demanding simultaneous consistency for entire sets of such processes, we are then able to calculate the masses of all the lowest pseudoscalar and vector qq-bar states with q = u,d,s and the Regge trajectories on which they lie. By making certain additional assumptions we are also able to do this with q = u,d,c and q = u,d,b. Our only arbitrary parameters are m/sub rho/, m/sub K/*, m/sub psi/, and m/sub Upsilon/, one of which merely serves to fix the energy scale. In contrast to many other approaches, a small m/sub π/ 2 /m/sub rho/ 2 ratio arises quite naturally in the present scheme

  1. Speed Consistency in the Smart Tachograph.

    Science.gov (United States)

    Borio, Daniele; Cano, Eduardo; Baldini, Gianmarco

    2018-05-16

    In the transportation sector, safety risks can be significantly reduced by monitoring the behaviour of drivers and by discouraging possible misconducts that entail fatigue and can increase the possibility of accidents. The Smart Tachograph (ST), the new revision of the Digital Tachograph (DT), has been designed with this purpose: to verify that speed limits and compulsory rest periods are respected by drivers. In order to operate properly, the ST periodically checks the consistency of data from different sensors, which can be potentially manipulated to avoid the monitoring of the driver behaviour. In this respect, the ST regulation specifies a test procedure to detect motion conflicts originating from inconsistencies between Global Navigation Satellite System (GNSS) and odometry data. This paper provides an experimental evaluation of the speed verification procedure specified by the ST regulation. Several hours of data were collected using three vehicles and considering light urban and highway environments. The vehicles were equipped with an On-Board Diagnostics (OBD) data reader and a GPS/Galileo receiver. The tests prescribed by the regulation were implemented with specific focus on synchronization aspects. The experimental analysis also considered aspects such as the impact of tunnels and the presence of data gaps. The analysis shows that the metrics selected for the tests are resilient to data gaps, latencies between GNSS and odometry data and simplistic manipulations such as data scaling. The new ST forces an attacker to falsify data from both sensors at the same time and in a coherent way. This makes more difficult the implementation of frauds in comparison to the current version of the DT.

  2. Design and measured performance of a solar chimney for natural-circulation solar-energy dryers

    International Nuclear Information System (INIS)

    Ekechukwu, O.V.; Norton, B.

    1995-10-01

    The design and construction of a solar chimney which was undertaken as part of a study on natural-circulation solar-energy dryers is reported. The experimental solar chimney consists of a 5.3m high and 1.64m diameter cylindrical polyethylene-clad vertical chamber, supported structurally by steel framework and draped internally with a selectively-absorbing surface. The performance of the chimney which was monitored extensively with and without the selective surface in place (to study the effectiveness of this design option) is also reported. (author). 14 refs, 7 figs

  3. Solar energy activities in the Arab countries

    International Nuclear Information System (INIS)

    Sayigh, A.A.M.

    1991-01-01

    The Arab countries, 22 in total, are divided into three groups. Group one consists of all countries of the Middle East. The second group is the Arabian Peninsula, and the third group consists of all Arab countries in Africa. The paper outlines the solar density and sunshine hours, as well as wind data in the region and compares them with some industrialized countries. Brief surveys of various solar energy projects are tabulated: that is solar, wind and biomass. Several specific major projects in various parts of the Arab World will be discussed. More specifically, the cooling of the solar energy research building in Baghdad (120 tons of solar absorption chillers, 80 tons of heat pumps), the heating of King Abdu-Asis Airborne and Physical Training School near Tabuk, Saudi Arabia, the 350 kW PV. field of the solar energy village near Riyadh and the 100 kW solar thermal plant in Kuwait are discussed. It is worth noting that the present photovoltaic capacity in the Arab world is more than 3.0 MW and the yearly installation potential per year is 2.0 MW. There are at least five photovoltaic production facilities in the Arab countries. Two of them in Saudi Arabia with capacity of 400 kW, one in Iraq with a capacity of 200 kW, one in Tunisia with a capacity of 100 kW and on in Algeria with capacity of 100 kW. The Arab countries can absorb 5MW per year and more countries like Egypt, Sudan, Morocco, Jordan and Libya are thinking of having their own production capabilities. Five desalination plants are also mentioned, plus the Yanbu plant of 240m/day, which is one of the largest in the world. The potential of wind energy utilisation is considered. Obstacles hindering the process of solar energy in the region are also outlined. (author). 11 refs, 1 fig., 4 tabs

  4. Hydrogen from solar energy

    Energy Technology Data Exchange (ETDEWEB)

    1977-04-01

    The long-range options of energy sources are the breeding reactor, nuclear fusion, and solar energy. Concerning solar energy three systems are being developed: First the photovoltaic cells which are almost ready for industrial production, but which are still too expensive - at least today. Secondly the thermal utilization of solar radiation. Compared to these, thirdly, the photobiological and photochemical possibilities of solar energy utilization have been somewhat neglected so far. However, the photolysis of water by solar energy is a very promising option for future energy demands. This can be done by making use of the photo-synthetic splitting of water in technical facilities or with semiconductors.

  5. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  6. Solar radiation absorbing material

    Science.gov (United States)

    Googin, John M.; Schmitt, Charles R.; Schreyer, James M.; Whitehead, Harlan D.

    1977-01-01

    Solar energy absorbing means in solar collectors are provided by a solar selective carbon surface. A solar selective carbon surface is a microporous carbon surface having pores within the range of 0.2 to 2 micrometers. Such a surface is provided in a microporous carbon article by controlling the pore size. A thermally conductive substrate is provided with a solar selective surface by adhering an array of carbon particles in a suitable binder to the substrate, a majority of said particles having diameters within the range of about 0.2-10 microns.

  7. Solar energy in Israel

    International Nuclear Information System (INIS)

    Zvirin, Y.; Zamkow, S.

    1993-01-01

    The state of Israel has been a pioneer in the solar energy development and utilization since it was founded. In the 50's solar domestic home heaters became commercially available. At the same time research work has been started in different areas of solar energy, which led to more advanced solar systems for additional applications. The presentation includes some details of commercial utilization of solar energy and a brief description of the main Research and Development projects in industry, universities and research institutes. (authors)

  8. The solar probe mission

    International Nuclear Information System (INIS)

    Feldman, W.C.; Anderson, J.; Bohlin, J.D.; Burlaga, L.F.; Farquhar, R.; Gloeckler, G.; Goldstein, B.E.; Harvey, J.W.; Holzer, T.E.; Jones, W.V.; Kellogg, P.J.; Krimigis, S.M.; Kundu, M.R.; Lazarus, A.J.; Mellott, M.M.; Parker, E.N.; Rosner, R.; Rottman, G.J.; Slavin, J.A.; Suess, S.T.; Tsurutani, B.T.; Woo, R.T.; Zwickl, R.D.

    1990-01-01

    The Solar Probe will deliver a 133.5 kg science payload into a 4 R s perihelion solar polar orbit (with the first perihelion passage in 2004) to explore in situ one of the last frontiers in the solar system---the solar corona. This mission is both affordable and technologically feasible. Using a payload of 12 (predominantly particles and fields) scientific experiments, it will be possible to answer many long-standing, fundamental problems concerning the structure and dynamics of the outer solar atmosphere, including the acceleration, storage, and transport of energetic particles near the Sun and in the inner ( s ) heliosphere

  9. Sun and solar flares

    Energy Technology Data Exchange (ETDEWEB)

    McKenna-Lawlor, S. (Saint Patrick' s Coll., Maynooth (Ireland))

    1982-07-01

    The subject is discussed under the headings: the sun's core (thermonuclear reactions, energy transfer from core through radiation zone, convection zone, photosphere, chromosphere and corona); the photosphere (convection, granulation, sunspots, magnetic fields, solar cycle, rotation of the sun); solar variability and paleoclimatic records (correlation of low solar activity with increased /sup 14/C production in atmosphere); the chromosphere and corona (turbulence, temperature, coronal streamers, energy transfer); solar flares (cosmic rays, aurorae, spectra, velocity of flares, prominences, mechanisms of flares); the solar wind.

  10. Solar thermal electricity generation

    Science.gov (United States)

    Gasemagha, Khairy Ramadan

    1993-01-01

    This report presents the results of modeling the thermal performance and economic feasibility of large (utility scale) and small solar thermal power plants for electricity generation. A number of solar concepts for power systems applications have been investigated. Each concept has been analyzed over a range of plant power ratings from 1 MW(sub e) to 300 MW(sub e) and over a range of capacity factors from a no-storage case (capacity factor of about 0.25 to 0.30) up to intermediate load capacity factors in the range of 0.46 to 0.60. The solar plant's economic viability is investigated by examining the effect of various parameters on the plant costs (both capital and O & M) and the levelized energy costs (LEC). The cost components are reported in six categories: collectors, energy transport, energy storage, energy conversion, balance of plant, and indirect/contingency costs. Concentrator and receiver costs are included in the collector category. Thermal and electric energy transport costs are included in the energy transport category. Costs for the thermal or electric storage are included in the energy storage category; energy conversion costs are included in the energy conversion category. The balance of plant cost category comprises the structures, land, service facilities, power conditioning, instrumentation and controls, and spare part costs. The indirect/contingency category consists of the indirect construction and the contingency costs. The concepts included in the study are (1) molten salt cavity central receiver with salt storage (PFCR/R-C-Salt); (2) molten salt external central receiver with salt storage (PFCR/R-E-Salt); (3) sodium external central receiver with sodium storage (PFCR/RE-Na); (4) sodium external central receiver with salt storage (PFCR/R-E-Na/Salt); (5) water/steam external central receiver with oil/rock storage (PFCR/R-E-W/S); (6) parabolic dish with stirling engine conversion and lead acid battery storage (PFDR/SLAB); (7) parabolic dish

  11. Performance comparison between silicon solar panel and dye-sensitized solar panel in Malaysia

    Science.gov (United States)

    Hamed, N. K. A.; Ahmad, M. K.; Urus, N. S. T.; Mohamad, F.; Nafarizal, N.; Ahmad, N.; Soon, C. F.; Ameruddin, A. S.; Faridah, A. B.; Shimomura, M.; Murakami, K.

    2017-09-01

    In carrying out experimental research in performance between silicon solar panel and dye-sensitive solar panel, we have been developing a device and a system. This system has been developed consisting of controllers, hardware and software. This system is capable to get most of the input sources. If only need to change the main circuit and coding for a different source input value. This device is able to get the ambient temperature, surface temperature, surrounding humidity, voltage with load, current with load, voltage without load and current without load and save the data into external memory. This device is able to withstand the heat and rain as it was fabricated in a waterproof box. This experiment was conducted to examine the performance of both the solar panels which are capable to maintain their stability and performance. A conclusion based on data populated, the distribution of data for dye-sensitized solar panel is much better than silicon solar panel as dye-sensitized solar panel is very sensitive to heat and not depend only on midday where is that is the maximum ambient temperature for both solar panel as silicon solar panel only can give maximum and high output only when midday.

  12. Fort Huachuca to Benefit from New Solar Technology: Dish-Stirling System Couples Solar Power with Engine to Generate Electricity

    National Research Council Canada - National Science Library

    1995-01-01

    ... in partnership with industry. A prototype dish-Stirling solar system, which consists of a large dish of solar concentrators and a Stirling heat engine, will be installed at Fort Huachuca in July and should be in operation about two weeks later...

  13. Solar Power Sources

    DEFF Research Database (Denmark)

    Kim, Katherine A.; Mentesidi, Konstantina; Yang, Yongheng

    2017-01-01

    a significant change. Beyond this energy transition, the still declining cost of the solar technology has become an important driving force for more solar-powered systems. However, high penetration of solar-powered systems also brings technical challenges to the entire energy systems. In order to fully address......Solar power is highly abundant, relatively reliable, and not limited to a geographic region, making it one of the most important renewable energy sources. Catering for a clean and green energy system, solar energy will be an active player in the future mixed power grid that is also undergoing...... those issues, the technological properties of solar power should be investigated. Thus, the basics of solar power technology will be introduced and discussed in this chapter....

  14. Solar energy modulator

    Science.gov (United States)

    Hale, R. R. (Inventor); Mcdougal, A. R.

    1984-01-01

    A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

  15. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2015-09-08

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  16. Frequency agile solar radiotelescope

    Science.gov (United States)

    Bastian, Tim S.

    2003-02-01

    The Frequency Agile Solar Radiotelescope (FASR) is a solar-dedicated, ground based, interferometric array optimized to perform broadband imaging spectroscopy from ~ 0.1-30+ GHz. It will do so with the angular, spectral, and temporal resolution required to exploit radio emission from the Sun as a diagnostic of the wide variety of astrophysical processes that occur there. FASR represents a major advance over existing radioheliographs, and is expected to remain the world's premier solar radio instrument for two decades or more after completion. FASR will be a versatile and powerful instrument, providing unique data to a broad users community. Solar, solar-terrestrial, and space physicists will exploit FASR to attack a broad science program, including problems of fundamental interest: coronal magnetography, solar flares and particle acceleration, drivers of space weather, and the thermal structure and dynamics of the solar atmosphere. A design study and implementation planning are underway. Recent progress is reviewed here.

  17. Photovoltaic solar concentrator

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2016-03-15

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  18. An innovative deployable solar panel system for Cubesats

    Science.gov (United States)

    Santoni, Fabio; Piergentili, Fabrizio; Donati, Serena; Perelli, Massimo; Negri, Andrea; Marino, Michele

    2014-02-01

    One of the main Cubesat bus limitations is the available on-board power. The maximum power obtained using body mounted solar panels and advanced triple junction solar cells on a triple unit Cubesat is typically less than 10 W. The Cubesat performance and the mission scenario opened to these small satellite systems could be greatly enhanced by an increase of the available power. This paper describes the design and realization of a modular deployable solar panel system for Cubesats, consisting of a modular hinge and spring system that can be potentially used on-board single (1U), double(2U), triple (3U) and six units (6U) Cubesats. The size of each solar panels is the size of a lateral Cubesat surface. The system developed is the basis for a SADA (Solar Array Drive Assembly), in which a maneuvering capability is added to the deployed solar array in order to follow the apparent motion of the sun. The system design trade-off is discussed, comparing different deployment concepts and architectures, leading to the final selection for the modular design. A prototype of the system has been realized for a 3U Cubesat, consisting of two deployable solar panel systems, made of three solar panels each, for a total of six deployed solar panels. The deployment system is based on a plastic fiber wire and thermal cutters, guaranteeing a suitable level of reliability. A test-bed for the solar panel deployment testing has been developed, supporting the solar array during deployment reproducing the dynamical situation in orbit. The results of the deployment system testing are discussed, including the design and realization of the test-bed, the mechanical stress given to the solar cells by the deployment accelerations and the overall system performance. The maximum power delivered by the system is about 50.4 W BOL, greatly enhancing the present Cubesat solar array performance.

  19. Status of Solar Sail Technology Within NASA

    Science.gov (United States)

    Johnson, Les; Young, Roy; Montgomery, Edward; Alhorn, Dean

    2010-01-01

    In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced and they successfully completed functional vacuum testing in NASA Glenn Research Center's (GRC's) Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by ATK Space Systems and L Garde, respectively. The sail systems consist of a central structure with four deployable booms that support the sails. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and were scalable to much larger solar sails perhaps as large as 150 m on a side. Computation modeling and analytical simulations were also performed to assess the scalability of the technology to the large sizes required to implement the first generation of missions using solar sails. Life and space environmental effects testing of sail and component materials were also conducted. NASA terminated funding for solar sails and other advanced space propulsion technologies shortly after these ground demonstrations were completed. In order to capitalize on the $30M investment made in solar sail technology to that point, NASA Marshall Space Flight Center (MSFC) funded the NanoSail-D, a subscale solar sail system designed for possible small spacecraft applications. The NanoSail-D mission flew on board the ill-fated Falcon-1 Rocket launched August 2, 2008, and due to the failure of that rocket, never achieved orbit. The NanoSail-D flight spare will be flown in the Fall of 2010. This paper will summarize NASA's investment in solar sail technology to-date and discuss future opportunities

  20. Status of solar sail technology within NASA

    Science.gov (United States)

    Johnson, Les; Young, Roy; Montgomery, Edward; Alhorn, Dean

    2011-12-01

    In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced. NASA has successfully completed functional vacuum testing in their Glenn Research Center's Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by Alliant Techsystems Space Systems and L'Garde, respectively. The sail systems consist of a central structure with four deployable booms that support each sail. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and are scalable to much larger solar sails - perhaps as large as 150 m on a side. Computation modeling and analytical simulations were performed in order to assess the scalability of the technology to the larger sizes that are required to implement the first generation of missions using solar sails. Furthermore, life and space environmental effects testing of sail and component materials was also conducted.NASA terminated funding for solar sails and other advanced space propulsion technologies shortly after these ground demonstrations were completed. In order to capitalize on the $30 M investment made in solar sail technology to that point, NASA Marshall Space Flight Center funded the NanoSail-D, a subscale solar sail system designed for possible small spacecraft applications. The NanoSail-D mission flew on board a Falcon-1 rocket, launched August 2, 2008. As a result of the failure of that rocket, the NanoSail-D was never successfully given the opportunity to achieve orbit. The NanoSail-D flight spare was flown in the Fall of 2010. This review paper summarizes NASA's investment in solar sail technology to date and discusses future opportunities.

  1. Photovoltaic. Solar thermal. Solar thermal electricity

    International Nuclear Information System (INIS)

    2009-01-01

    The year 2008 was excellent for solar energy in the European Union. The growth of the installed capacity for photovoltaic was +159% (it means +4747.018 MW) to reach 9689.952 MW and that for solar thermal was +51.5% (it means +3172.5 MW) to reach 19982.7 MW. Worldwide concentrated solar thermal capacity stood at 679 MW in 2009, while this figure may seem low, the sector has a promising future ahead of it. (A.C.)

  2. 3D-printed concentrator arrays for external light trapping on thin film solar cells

    NARCIS (Netherlands)

    van Dijk, Lourens; Marcus, E.A.P.; Oostra, A.J.; Schropp, R.E.I.; Vece, Di M.

    2015-01-01

    After our recent demonstration of a 3D-printed external light trap on a small solar cell, we now consider its potential for large solar panels. An external light trap consists of a parabolic concentrator and a spacer that redirects the photons that are reflected by the solar cell back towards the

  3. 3D-printed concentrator arrays for external light trapping on thin film solar cells

    NARCIS (Netherlands)

    van Dijk, Lourens; Marcus, E. A. Pepijn; Oostra, A. Jolt; Schropp, Ruud E. I.; Di Vece, Marcel

    After our recent demonstration of a 3D-printed external light trap on a small solar cell, we now consider its potential for large solar panels. An external light trap consists of a parabolic concentrator and a spacer that redirects the photons that are reflected by the solar cell back towards the

  4. A Model for Infusing Energy Concepts into Vocational Education Programs. Advanced Solar Systems.

    Science.gov (United States)

    Delta Vocational Technical School, Marked Tree, AR.

    This instructional unit consists of materials designed to help students understand terms associated with solar energy; identify components of advanced solar systems; and identify applications of solar energy in business, industry, agriculture, and photovoltaics. Included in the unit are the following materials: suggested activities, instructional…

  5. 77 FR 4989 - Turning Point Solar LLC: Notice of Availability of an Environmental Assessment

    Science.gov (United States)

    2012-02-01

    ... monocrystalline photovoltaic panels mounted on fixed solar racking equipment and the construction of access roads... DEPARTMENT OF AGRICULTURE Rural Utilities Service Turning Point Solar LLC: Notice of Availability... possible financial assistance for a proposal by Turning Point Solar LCC (TPS). The proposal consists of...

  6. Solar-heated municipal swimming pools, a case study: Dade County, Florida

    Science.gov (United States)

    Levin, M.

    1981-09-01

    The installation of a solar energy system to heat the water in the swimming pool in one of Dade County, Florida's major parks is described. The mechanics of solar heated swimming pools are explained. The solar heating system consists of 216 unglazed polypropylene tube collectors, a differential thermostat, and the distribution system. The systems performance and economics as well as future plants are discussed.

  7. Solar wind structure suggested by bimodal correlations of solar wind speed and density between the spacecraft SOHO and Wind

    Science.gov (United States)

    Ogilvie, K. W.; Coplan, M. A.; Roberts, D. A.; Ipavich, F.

    2007-08-01

    We calculate the cross-spacecraft maximum lagged-cross-correlation coefficients for 2-hour intervals of solar wind speed and density measurements made by the plasma instruments on the Solar and Heliospheric Observatory (SOHO) and Wind spacecraft over the period from 1996, the minimum of solar cycle 23, through the end of 2005. During this period, SOHO was located at L1, about 200 R E upstream from the Earth, while Wind spent most of the time in the interplanetary medium at distances of more than 100 R E from the Earth. Yearly histograms of the maximum, time-lagged correlation coefficients for both the speed and density are bimodal in shape, suggesting the existence of two distinct solar wind regimes. The larger correlation coefficients we suggest are due to structured solar wind, including discontinuities and shocks, while the smaller are likely due to Alfvénic turbulence. While further work will be required to firmly establish the physical nature of the two populations, the results of the analysis are consistent with a solar wind that consists of turbulence from quiet regions of the Sun interspersed with highly filamentary structures largely convected from regions in the inner solar corona. The bimodal appearance of the distributions is less evident in the solar wind speed than in the density correlations, consistent with the observation that the filamentary structures are convected with nearly constant speed by the time they reach 1 AU. We also find that at solar minimum the fits for the density correlations have smaller high-correlation components than at solar maximum. We interpret this as due to the presence of more relatively uniform Alfvénic regions at solar minimum than at solar maximum.

  8. Solar engineering of thermal processes

    CERN Document Server

    Duffie, John A

    2013-01-01

    The updated fourth edition of the ""bible"" of solar energy theory and applications Over several editions, Solar Engineering of Thermal Processes has become a classic solar engineering text and reference. This revised Fourth Edition offers current coverage of solar energy theory, systems design, and applications in different market sectors along with an emphasis on solar system design and analysis using simulations to help readers translate theory into practice. An important resource for students of solar engineering, solar energy, and alternative energy as well

  9. Assessing distances and consistency of kinematics in Gaia/TGAS

    Science.gov (United States)

    Schönrich, Ralph; Aumer, Michael

    2017-12-01

    We apply the statistical methods by Schönrich, Binney & Asplund to assess the quality of distances and kinematics in the Radial Velocity Experiment (RAVE)-Tycho-Gaia Astrometric Solution (TGAS) and Large Sky Area Multiobject Fiber Spectroscopic Telescope (LAMOST)-TGAS samples of Solar neighbourhood stars. These methods yield a nominal distance accuracy of 1-2 per cent. Other than common tests on parallax accuracy, they directly test distance estimations including the effects of distance priors. We show how to construct these priors including the survey selection functions (SSFs) directly from the data. We demonstrate that neglecting the SSFs causes severe distance biases. Due to the decline of the SSFs in distance, the simple 1/parallax estimate only mildly underestimates distances. We test the accuracy of measured line-of-sight velocities (vlos) by binning the samples in the nominal vlos uncertainties. We find: (i) the LAMOST vlos have a ∼-5 km s-1 offset; (ii) the average LAMOST measurement error for vlos is ∼7 km s-1, significantly smaller than, and nearly uncorrelated with the nominal LAMOST estimates. The RAVE sample shows either a moderate distance underestimate, or an unaccounted source of vlos dispersion (e∥) from measurement errors and binary stars. For a subsample of suspected binary stars in RAVE, our methods indicate significant distance underestimates. Separating a sample in metallicity or kinematics to select thick-disc/halo stars, discriminates between distance bias and e∥. For LAMOST, this separation yields consistency with pure vlos measurement errors. We find an anomaly near longitude l ∼ (300 ± 60)° and distance s ∼ (0.32 ± 0.03) kpc on both sides of the galactic plane, which could be explained by either a localized distance error or a breathing mode.

  10. Solar Preheated Ventilation - Innovative Solar Technology

    National Research Council Canada - National Science Library

    Gaberson, Howard

    1999-01-01

    .... This innovative technology applies to both new construction or rehabilitation projects. This TDS introduces this low maintenance solar technology for consideration in all future industrial ventilation or HVAC projects...

  11. Installation package for the Solaron solar subsystem

    Science.gov (United States)

    1979-01-01

    Information that is intended to be a guide for installation, operation, and maintenance of the various solar subsystems is presented. The subsystems consist of the following: collectors, storage, transport (air handler) and controller for heat pump and peak storage. Two prototype residential systems were installed at Akron, Ohio, and Duffield, Virginia.

  12. Distributed series resistance effects in solar cells

    DEFF Research Database (Denmark)

    Nielsen, Lars Drud

    1982-01-01

    A mathematical treatment is presented of the effects of one-dimensional distributed series resistance in solar cells. A general perturbation theory is developed, including consistently the induced spatial variation of diode current density and leading to a first-order equivalent lumped resistance...

  13. National Community Solar Platform

    Energy Technology Data Exchange (ETDEWEB)

    Rupert, Bart [Clean Energy Collective, Louisville, CO (United States)

    2016-06-30

    This project was created to provide a National Community Solar Platform (NCSP) portal known as Community Solar Hub, that is available to any entity or individual who wants to develop community solar. This has been done by providing a comprehensive portal to make CEC’s solutions, and other proven community solar solutions, externally available for everyone to access – making the process easy through proven platforms to protect subscribers, developers and utilities. The successful completion of this project provides these tools via a web platform and integration APIs, a wide spectrum of community solar projects included in the platform, multiple groups of customers (utilities, EPCs, and advocates) using the platform to develop community solar, and open access to anyone interested in community solar. CEC’s Incubator project includes web-based informational resources, integrated systems for project information and billing systems, and engagement with customers and users by community solar experts. The combined effort externalizes much of Clean Energy Collective’s industry-leading expertise, allowing third parties to develop community solar without duplicating expensive start-up efforts. The availability of this platform creates community solar projects that are cheaper to build and cheaper to participate in, furthering the goals of DOE’s SunShot Initiative. Final SF 425 Final SF 428 Final DOE F 2050.11 Final Report Narrative

  14. Solar energy guide

    International Nuclear Information System (INIS)

    Lentz, A.; Winter, R.

    1993-07-01

    Many aspects with regard to the practical use of solar energy are discussed. This guide is aimed at informing local and regional administrators, committee members of housing corporations and public utilities and public relations officers on the possibilities to use solar energy. In chapter one an overview is given of the use of solar energy in the housing sector, the recreational sector, agricultural sector, industry, trade and other sectors. In the chapters two, three and four attention is paid to passive solar energy, active thermal solar energy and photovoltaic energy respectively. In the chapters five and six aspects concerning the implementation of solar energy systems in practice are discussed. First an outline of the parties involved in implementing solar energy is given: the municipality, the energy utility, the province, local authorities, advisors, housing constructors and the occupants of the buildings. Then attention is paid to the consequences of implementing solar energy for the building inspection and regulations, the finances, energy savings and the environment. In chapter seven an overview is given of the subsidy regulations of the European Community, the Dutch national and local governments. Chapter contains addresses of solar thermal systems, photovoltaic systems and other institutes operating in the field of solar energy, as well as the titles of a number of brochures and courses. 51 figs., 7 tabs., 86 refs

  15. Solar Market Research and Analysis | Solar Research | NREL

    Science.gov (United States)

    Analysis Solar Market Research and Analysis Through rigorous data collection, analysis, and stakeholder engagement, NREL's Solar Market Research and Analysis efforts further solar technologies' role in solar panels. Key areas for NREL's solar market research and analysis portfolio include the following

  16. Solar Market Research and Analysis Projects | Solar Research | NREL

    Science.gov (United States)

    Market Research and Analysis Projects Solar Market Research and Analysis Projects Solar market research and analysis efforts at NREL seek to further solar technologies' role in supporting a more . Midscale Commercial Market Solar Analysis NREL experts are providing analysis to expand the midscale solar

  17. The Solar Energy Trifecta: Solar + Storage + Net Metering | State, Local,

    Science.gov (United States)

    and Tribal Governments | NREL The Solar Energy Trifecta: Solar + Storage + Net Metering The Solar Energy Trifecta: Solar + Storage + Net Metering February 12, 2018 by Benjamin Mow Massachusetts (DPU) seeking an advisory ruling on the eligibility of pairing solar-plus-storage systems with current

  18. DIY Solar Market Analysis Webinar Series: Solar Resource and Technical

    Science.gov (United States)

    Series: Solar Resource and Technical Potential DIY Solar Market Analysis Webinar Series: Solar Resource and Technical Potential Wednesday, June 11, 2014 As part of a Do-It-Yourself Solar Market Analysis Potential | State, Local, and Tribal Governments | NREL DIY Solar Market Analysis Webinar

  19. Solar production of lime; Solare Herstellung von Kalk

    Energy Technology Data Exchange (ETDEWEB)

    Meier, A.; Bonaldi, E.

    2002-07-01

    A novel indirect-heated solar reactor for the solar production of lime (CaO) was designed, built and tested in a solar furnace at the Paul Scherrer Institute PSI, at Villigen, Switzerland. This 10-kW reactor is operated in continuous mode and consists of a tilted rotary kiln with a specially designed high-temperature resistant blackbody absorber made from SiC and a preheating chamber where the small-grained limestone particles are preheated almost to the reaction temperature. The transition to an indirect-heated reactor including additional design changes was successful: (1) With the improved particle feeding system, the maximum CaO production rate was increased from 1.5 kg/hr to about 4 kg/hr. (2) The heat losses were significantly reduced, and consequently the reactor efficiency was increased to more than 30% with a maximum near 35%, while still maintaining a high degree of calcination exceeding 98%. (3) The SiC absorber withstood thermal shocks at temperatures up to 1,600 K. (author)

  20. Solar Thermal Energy; Energia Solar Termica

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Martinez, M; Cuesta-Santianes, M J; Cabrera Jimenez, J A

    2008-07-01

    Approximately, 50 % of worldwide primary energy consumption is done in the form of heat in applications with a temperature lower than 250 degree centigree (low-medium temperature heat). These data clearly demonstrate the great potential of solar thermal energy to substitute conventional fossil fuels, which are becoming more expensive and are responsible for global warming. Low-medium temperature solar thermal energy is mainly used to obtain domestic hot water and provide space heating. Active solar thermal systems are those related to the use of solar thermal collectors. This study is dealing with low temperature solar thermal applications, mainly focusing on active solar thermal systems. This kind of systems has been extensively growing worldwide during the last years. At the end of 2006, the collector capacity in operation worldwide equalled 127.8 GWth. The technology is considered to be already developed and actions should be aimed at favouring a greater market penetration: diffusion, financial support, regulations establishment, etc. China and USA are the leading countries with a technology based on evacuated tube collectors and unglazed collectors, respectively. The rest of the world markets are dominated by the flat glazed collectors technology. (Author) 15 refs.

  1. Time-Consistent and Market-Consistent Evaluations (Revised version of 2012-086)

    NARCIS (Netherlands)

    Stadje, M.A.; Pelsser, A.

    2014-01-01

    Abstract: We consider evaluation methods for payoffs with an inherent financial risk as encountered for instance for portfolios held by pension funds and insurance companies. Pricing such payoffs in a way consistent to market prices typically involves combining actuarial techniques with methods from

  2. High-energy particles associated with solar flares

    International Nuclear Information System (INIS)

    Sakurai, K.; Klimas, A.J.

    1974-05-01

    High energy particles, the so-called solar cosmic rays, are often generated in association with solar flares, and then emitted into interplanetary space. These particles, consisting of electrons, protons, and other heavier nuclei, including the iron-group, are accelerated in the vicinity of the flare. By studying the temporal and spatial variation of these particles near the earth's orbit, their storage and release mechanisms in the solar corona and their propagation mechanism can be understood. The details of the nuclear composition and the rigidity spectrum for each nuclear component of the solar cosmic rays are important for investigating the acceleration mechanism in solar flares. The timing and efficiency of the acceleration process can also be investigated by using this information. These problems are described in some detail by using observational results on solar cosmic rays and associated phenomena. (U.S.)

  3. Design And Construction Of Microcontroller Based Solar Battery Charger

    Directory of Open Access Journals (Sweden)

    Zar Ni Tun

    2015-08-01

    Full Text Available This research paper describes a microcontroller based battery charger by using solar energy. Solar-powered charging systems are already available in rural as well as urban areas. Solar energy is widely used around the worldwide. This system converts solar energy to electrical energy and stores it in a battery. Photovoltaic panel is used to convert solar energy to electrical energy and stored in a 12V battery. Battery is the main component in solar charging system to store the energy generated from sunlight for various application. This system requires sensor to sense whether the battery is fully charged or not. Microcontroller is the heart of the circuit. Lead-acid batteries are the most commonly used power source for many applications. This system consists of voltage sensing charging controlling and display unit.

  4. Solar heating and hot water system installed at Arlington Raquetball Club, Arlington, Virginia

    Science.gov (United States)

    1981-01-01

    A solar space and water heating system is described. The solar energy system consists of 2,520 sq. ft. of flat plate solar collectors and a 4,000 gallon solar storage tank. The transfer medium in the forced closed loop is a nontoxic antifreeze solution (50 percent water, 50 percent propylene glycol). The service hot water system consists of a preheat coil (60 ft. of 1 1/4 in copper tubing) located in the upper third of the solar storage tank and a recirculation loop between the preheat coil and the existing electric water heaters. The space heating system consists of two separate water to air heat exchangers located in the ducts of the existing space heating/cooling systems. The heating water is supplied from the solar storage tank. Extracts from site files, specification references for solar modifications to existing building heating and hot water systems, and installation, operation and maintenance instructions are included.

  5. Automatic Detect and Trace of Solar Filaments

    Science.gov (United States)

    Fang, Cheng; Chen, P. F.; Tang, Yu-hua; Hao, Qi; Guo, Yang

    We developed a series of methods to automatically detect and trace solar filaments in solar Hα images. The programs are able to not only recognize filaments and determine their properties, such as the position, the area and other relevant parameters, but also to trace the daily evolution of the filaments. For solar full disk Hα images, the method consists of three parts: first, preprocessing is applied to correct the original images; second, the Canny edge-detection method is used to detect the filaments; third, filament properties are recognized through the morphological operators. For each Hα filament and its barb features, we introduced the unweighted undirected graph concept and adopted Dijkstra shortest-path algorithm to recognize the filament spine; then, using polarity inversion line shift method for measuring the polarities in both sides of the filament to determine the filament axis chirality; finally, employing connected components labeling method to identify the barbs and calculating the angle between each barb and spine to indicate the barb chirality. Our algorithms are applied to the observations from varied observatories, including the Optical & Near Infrared Solar Eruption Tracer (ONSET) in Nanjing University, Mauna Loa Solar Observatory (MLSO) and Big Bear Solar Observatory (BBSO). The programs are demonstrated to be effective and efficient. We used our method to automatically process and analyze 3470 images obtained by MLSO from January 1998 to December 2009, and a butterfly diagram of filaments is obtained. It shows that the latitudinal migration of solar filaments has three trends in the Solar Cycle 23: The drift velocity was fast from 1998 to the solar maximum; after the solar maximum, it became relatively slow and after 2006, the migration became divergent, signifying the solar minimum. About 60% filaments with the latitudes larger than 50 degree migrate towards the Polar Regions with relatively high velocities, and the latitudinal migrating

  6. Characteristics of shocks in the solar corona, as inferred from radio, optical, and theoretical investigations

    Science.gov (United States)

    Maxwell, A.; Dryer, M.

    1982-01-01

    Solar radio bursts of spectral type II provide one of the chief diagnostics for the propagation of shocks through the solar corona. Radio data on the shocks are compared with computer models for propagation of fast-mode MHD shocks through the solar corona. Data on coronal shocks and high-velocity ejecta from solar flares are then discussed in terms of a general model consisting of three main velocity regimes.

  7. Hybrids of Solar Sail, Solar Electric, and Solar Thermal Propulsion for Solar-System Exploration

    Science.gov (United States)

    Wilcox, Brian H.

    2012-01-01

    Solar sails have long been known to be an attractive method of propulsion in the inner solar system if the areal density of the overall spacecraft (S/C) could be reduced to approx.10 g/sq m. It has also long been recognized that the figure (precise shape) of useful solar sails needs to be reasonably good, so that the reflected light goes mostly in the desired direction. If one could make large reflective surfaces with reasonable figure at an areal density of approx.10 g/sq m, then several other attractive options emerge. One is to use such sails as solar concentrators for solar-electric propulsion. Current flight solar arrays have a specific output of approx. 100W/kg at 1 Astronomical Unit (AU) from the sun, and near-term advances promise to significantly increase this figure. A S/C with an areal density of 10 g/sq m could accelerate up to 29 km/s per year as a solar sail at 1 AU. Using the same sail as a concentrator at 30 AU, the same spacecraft could have up to approx. 45 W of electric power per kg of total S/C mass available for electric propulsion (EP). With an EP system that is 50% power-efficient, exhausting 10% of the initial S/C mass per year as propellant, the exhaust velocity is approx. 119 km/s and the acceleration is approx. 12 km/s per year. This hybrid thus opens attractive options for missions to the outer solar system, including sample-return missions. If solar-thermal propulsion were perfected, it would offer an attractive intermediate between solar sailing in the inner solar system and solar electric propulsion for the outer solar system. In the example above, both the solar sail and solar electric systems don't have a specific impulse that is near-optimal for the mission. Solar thermal propulsion, with an exhaust velocity of the order of 10 km/s, is better matched to many solar system exploration missions. This paper derives the basic relationships between these three propulsion options and gives examples of missions that might be enabled by

  8. Solar opacities constrained by solar neutrinos and solar oscillations

    International Nuclear Information System (INIS)

    Cox, A.N.

    1989-01-01

    This review discusses the current situation for opacities at the solar center, the solar surface, and for the few million kelvin temperatures that occur below the convection zone. The solar center conditions are important because they are crucial for the neutrino production, which continues to be predicted about 4 times that observed. The main extinction effects there are free-free photon absorption in the electric fields of the hydrogen, helium and the CNO atoms, free electron scattering of photons, and the bound-free and bound-bound absorption of photons by iron atoms with two electrons in the 1s bound level. An assumption that the iron is condensed-out below the convection zone, and the opacity in the central regions is thereby reduced, results in about a 25 percent reduction in the central opacity but only a 5 percent reduction at the base of the convection zone. Furthermore, the p-mode solar oscillations are changed with this assumption, and do not fit the observed ones as well as for standard models. A discussion of the large effective opacity reduction by weakly interacting massive particles also results in poor agreement with observed p-mode oscillation frequencies. The much larger opacities for the solar surface layers from the Los Alamos Astrophysical Opacity Library instead of the widely used Cox and Tabor values show small improvements in oscillation frequency predictions, but the largest effect is in the discussion of p-mode stability. Solar oscillation frequencies can serve as an opacity experiment for the temperatures and densities, respectively, of a few million kelvin and between 0.1 and 10 g/cm 3 . Current oscillation frequency calculations indicate that possibly the Opacity Library values need an increase of typically 15 percent just at the bottom of the convection zone at 3 x 10 6 K. 41 refs., 15 figs., 1 tab

  9. Development of Solar Powered Irrigation System

    International Nuclear Information System (INIS)

    Abdelkerim, A I; Eusuf, M M R Sami; Salami, M J E; Aibinu, A; Eusuf, M A

    2013-01-01

    Development of a solar powered irrigation system has been discussed in this paper. This system would be SCADA-based and quite useful in areas where there is plenty of sunshine but insufficient water to carry out farming activities, such as rubber plantation, strawberry plantation, or any plantation, that requires frequent watering. The system is powered by solar system as a renewable energy which uses solar panel module to convert Sunlight into electricity. The development and implementation of an automated SCADA controlled system that uses PLC as a controller is significant to agricultural, oil and gas monitoring and control purpose purposes. In addition, the system is powered by an intelligent solar system in which solar panel targets the radiation from the Sun. Other than that, the solar system has reduced energy cost as well as pollution. The system is equipped with four input sensors; two soil moisture sensors, two level detection sensors. Soil moisture sensor measures the humidity of the soil, whereas the level detection sensors detect the level of water in the tank. The output sides consist of two solenoid valves, which are controlled respectively by two moistures sensors

  10. Solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L.

    2007-09-18

    A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  11. Solar energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Kistler, J.

    1981-08-05

    The photovoltaic generator is the central part of all solar systems. Flat solar cells embedded in glass are preferred which can also convert diffuse solar radiation. Hybrid modules generate electrical and thermal energy simultaneously. With decreasing generator cost, the cost of energy storage becomes critical. Development activities are mostly directed on the development of stationary lead accumulator batteries and the electronic charging and protective systems. The block diagram of the current converter is presented, and applications of solar systems in domestic heating engineering, transportation technology, communications, and hydrological engineering. Solar villages are recommended which, established in bilateral cooperation with Third World authorities, may demonstrate the advantages of solar energy in heat and electric power generation.

  12. Solar panel cleaning robot

    Science.gov (United States)

    Nalladhimmu, Pavan Kumar Reddy; Priyadarshini, S.

    2018-04-01

    As the demand of electricity is increasing, there is need to using the renewable sources to produce the energy at present of power shortage, the use of solar energy could be beneficial to great extent and easy to get the maximum efficiency. There is an urgent in improving the efficiency of solar power generation. Current solar panels setups take a major power loss when unwanted obstructions cover the surface of the panels. To make solar energy more efficiency of solar array systems must be maximized efficiency evaluation of PV panels, that has been discussed with particular attention to the presence of dust on the efficiency of the PV panels have been highlighted. This paper gives the how the solar panel cleaning system works and designing of the cleaning system.

  13. Initial operation of a solar heating and cooling system in a full-scale solar building test facility

    Science.gov (United States)

    Knoll, R. H.; Miao, D.; Hamlet, I. L.; Jensen, R. N.

    1976-01-01

    The Solar Building Test Facility (SBTF) located at Hampton, Virginia became operational in early summer of 1976. This facility is a joint effort by NASA-Lewis and NASA-Langley to advance the technology for heating and cooling of office buildings with solar energy. Its purposes are to (1) test system components which include high-performing collectors, (2) test performance of complete solar heating and cooling system, (3) investigate component interactions and (4) investigate durability, maintenance and reliability of components. The SBTF consists of a 50,000 square foot office building modified to accept solar heated water for operation of an absorption air conditioner and for the baseboard heating system. A 12,666 square foot solar collector field with a 30,000 gallon storage tank provides the solar heated water. A description of the system and the collectors selected is given here, along with the objectives, test approach, expected system performance and some preliminary results.

  14. Solar Renewable Energy. Teaching Unit.

    Science.gov (United States)

    Buchanan, Marion; And Others

    This unit develops the concept of solar energy as a renewable resource. It includes: (1) an introductory section (developing understandings of photosynthesis and impact of solar energy); (2) information on solar energy use (including applications and geographic limitations of solar energy use); and (3) future considerations of solar energy…

  15. Bright Idea: Solar Energy Primer.

    Science.gov (United States)

    Missouri State Dept. of Natural Resources, Jefferson City.

    This booklet is intended to address questions most frequently asked about solar energy. It provides basic information and a starting point for prospective solar energy users. Information includes discussion of solar space heating, solar water heating, and solar greenhouses. (Author/RE)

  16. Virginia Solar Pathways Project Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Bond, Katharine; Cosby, Sarah

    2018-03-28

    . The second integration study considered the broader frameworks involving interconnection of large electric generating units to the regional transmission network that moves power over long distances before being stepped down into the electric distribution system. A third study, conducted by the National Renewable Energy Laboratory, assessed solar economics in key states in the mid-Atlantic and Southeast regions, which share demographic and policy characteristics with Virginia. It also catalogued the experiences of utilities in several other states beyond the mid-Atlantic and Southeast regions with respect to examination of utility program elements, business practices, and tax rules and their impacts on soft costs of solar development, which consist of expenditures related to non-hardware aspects, such as permitting, interconnection, inspections, insurance, customer acquisition, project design, installation labor, etc. A fourth study, completed by the Smart Electric Power Alliance examined nine community solar programs at utilities in other states around the country for the purpose of developing a community solar program in Virginia. The comprehensive Solar Strategy resulting from this Project was developed based on a list of foundational objectives. Based on these objectives, the Solar Strategy was intended to: • Be achieved within Virginia’s fully regulated utility framework; • Be informed by input from a broad range of stakeholders and encourage continuation of the collaborative process; • Involve data-driven decision-making, including studies conducted as part of the Project along with data analysis and input from subject matter experts; • Support sustainable expansion of solar generation that promotes affordable electric rates and Virginia’s economy and economic development; • Focus on the customer through: o Fair allocation of quantifiable costs and benefits via properly designed rate structures, while providing enhanced access to information, choice

  17. Solar Observations at Submillimeter Wavelengths

    Science.gov (United States)

    Kaufmann, P.

    We review earlier to recent observational evidences and theoretical motivations leading to a renewed interest to observe flares in the submillimeter (submm) - infrared (IR) range of wavelengths. We describe the new solar dedicated submillimeter wave telescope which began operations at El Leoncito in the Argentina Andes: the SST project. It consists of focal plane arrays of two 405 GHz and four 212 GHz radiometers placed in a 1.5-m radome-enclosed Cassegrain antenna, operating simultaneously with one millisecond time resolution. The first solar events analyzed exhibited the onset of rapid submm-wave spikes (100-300 ms), well associated to other flare manifestations, especially at X-rays. The spikes positions were found scattered over the flaring source by tens of arcseconds. For one event an excellent association was found between the gamma-ray emission time profile and the rate of occurrence of submm-wave rapid spikes. The preliminary results favour the idea that bulk burst emissions are a response to numerous fast energetic injections, discrete in time, produced at different spatial positions over the flaring region. Coronal mass ejections were associated to the events studied. Their trajectories extrapolated to the solar surface appear to correspond to the onset time of the submm-wave spikes, which might represent an early signature of the CME's initial acceleration process.

  18. Solar Retinopathy: A Multimodal Analysis

    Directory of Open Access Journals (Sweden)

    Claudia Bruè

    2013-01-01

    Full Text Available Purpose. Solar retinopathy is a rare clinical disturbance, for which spectral-domain optical coherence tomography (SD-OCT findings are not always consistent. We report on two cases of solar retinopathy and discuss its differential diagnosis. Methods. This is an observational case study. Results. A 12-year-old female was referred to ophthalmology for bilateral scotoma. Visual acuity was 20/50 in both eyes. Fundus examination was unremarkable, except for slight yellowish material in the central macula, bilaterally. SD-OCT revealed juxtafoveal microcystic cavities in the outer retina, interruption of the external limiting membrane and the inner and outer segment junctions, with disorganized material in the vitelliform space. Fundus autofluorescence showed hypoautofluorescence surrounded by a relatively hyperautofluorescent ring, bilaterally. Similar clinical and morphological findings were detected in a 27-year-old male. Conclusions. Solar retinopathy has a subtle presentation and patients often deny sun-gazing. SD-OCT and fundus autofluorescence are noninvasive and useful tools for its diagnosis.

  19. GISOT: a giant solar telescope

    Science.gov (United States)

    Hammerschlag, Robert H.; von der Lühe, Oskar F.; Bettonvil, Felix C.; Jägers, Aswin P.; Snik, Frans

    2004-10-01

    A concept is presented for an extremely large high-resolution solar telescope with an aperture of 11 m and diffraction limited for visual wavelengths. The structure of GISOT will be transparent to wind and placed on a transparent stiff tower. For efficient wind flushing, all optics, including the primary mirror, will be located above the elevation axis. The aperture will be of the order of 11 m, not rotatively symmetrical, but of an elongated shape with dimensions 11 x 4 m. It consists of a central on-axis 4 m mirror with on both sides 3 pieces of 2 m mirrors. The optical layout will be kept simple to guarantee quality and minimize stray light. A Coudé room for instruments is planned below the telescope. The telescope will not be housed in a dome-like construction, which interferes with the open principle. Instead the telescope will be protected by a foldable tent construction with a diameter of the order of 30 m, which doesn"t form any obstruction during observations, but can withstand the severe weather circumstances on mountain sites. Because of the nature of the solar scene, extremely high resolution in only one dimension is sufficient to solve many exciting problems in solar physics and in this respect the concept of GISOT is very promising.

  20. Solar photocatalyzed process economics

    International Nuclear Information System (INIS)

    Link, H.

    1990-01-01

    This paper describes the Solar Energy Research Institute (SERI) cost estimates for solar water detoxification systems based on the best available information as of October 1990. Comparative costs are also provided for competitive conventional technologies which are presently applied in the water detoxification market. Although costs for solar photocatalytic systems are presently higher than those of competitive technologies, cost and performance improvements should lead to cost competitiveness by 1995

  1. Solar energy emplacement developer

    Science.gov (United States)

    Mortensen, Michael; Sauls, Bob

    1991-01-01

    A preliminary design was developed for a Lunar Power System (LPS) composed of photovoltaic arrays and microwave reflectors fabricated from lunar materials. The LPS will collect solar energy on the surface of the Moon, transform it into microwave energy, and beam it back to Earth where it will be converted into usable energy. The Solar Energy Emplacement Developer (SEED) proposed will use a similar sort of solar energy collection and dispersement to power the systems that will construct the LPS.

  2. Solar power in Finland

    International Nuclear Information System (INIS)

    Vesa, A.M.

    2004-01-01

    Solar cells, or photovoltaic units, have provided a useful supply of energy for low-power, non-gridconnected applications in Finland for some years. Applications have included navigational buoys, base stations for mobile phone networks, and appliances in holiday homes. Solar-powered systems have also been used in connection with grid power for over a decade, in Finland and elsewhere, and have proved generally successful - and solar energy is emerging as an increasingly interesting alternative for distributed electricity generation

  3. The solar neutrino problem

    International Nuclear Information System (INIS)

    Bahcall, J.N.

    1986-01-01

    The observed capture rate for solar neutrinos in the /sup 37/Cl detector is lower than the predicted capture rate. This discrepancy between theory and observation is known as the 'solar neutrino problem.' The author reviews the basic elements in this problem: the detector efficiency, the theory of stellar (solar) evolution, the nuclear physics of energy generation, and the uncertainties in the predictions. He also answers the questions of: So What? and What Next?

  4. Solar Asset Management Software

    Energy Technology Data Exchange (ETDEWEB)

    Iverson, Aaron [Ra Power Management, Inc., Oakland, CA (United States); Zviagin, George [Ra Power Management, Inc., Oakland, CA (United States)

    2016-09-30

    Ra Power Management (RPM) has developed a cloud based software platform that manages the financial and operational functions of third party financed solar projects throughout their lifecycle. RPM’s software streamlines and automates the sales, financing, and management of a portfolio of solar assets. The software helps solar developers automate the most difficult aspects of asset management, leading to increased transparency, efficiency, and reduction in human error. More importantly, our platform will help developers save money by improving their operating margins.

  5. Profile in solar

    International Nuclear Information System (INIS)

    Cohen, S.; Woods, A.

    1991-01-01

    This article reviews an innovative solar hot water heater and its inventor/entrepreneur. It includes the inventor's strategy for developing and marketing the product and his ideas on the state of the solar industry in general. There is a brief description of the solar water heater which has as prominent features its skylight-like appearance, resistance to freeze damage, simplicity and low cost

  6. Performance tests and efficiency analysis of Solar Invictus 53S - A parabolic dish solar collector for direct steam generation

    Science.gov (United States)

    Jamil, Umer; Ali, Wajahat

    2016-05-01

    This paper presents the results of performance tests conducted on Solar Invictus 53S `system'; an economically effective solar steam generation solution designed and developed by ZED Solar Ltd. The system consists of a dual axis tracking parabolic solar dish and bespoke cavity type receiver, which works as a Once Through Solar Steam Generator `OTSSG' mounted at the focal point of the dish. The overall performance and efficiency of the system depends primarily on the optical efficiency of the solar dish and thermal efficiency of the OTSSG. Optical testing performed include `on sun' tests using CCD camera images and `burn plate' testing to evaluate the sunspot for size and quality. The intercept factor was calculated using a colour look-back method to determine the percentage of solar rays focused into the receiver. Solar dish tracking stability tests were carried out at different times of day to account for varying dish elevation angles and positions, movement of the sunspot centroid was recorded and logged using a CCD camera. Finally the overall performance and net solar to steam efficiency of the system was calculated by experimentally measuring the output steam parameters at varying Direct Normal Insolation (DNI) levels at ZED Solar's test facility in Lahore, Pakistan. Thermal losses from OTSSG were calculated using the known optical efficiency and measured changes in output steam enthalpy.

  7. Consistently Showing Your Best Side? Intra-individual Consistency in #Selfie Pose Orientation

    Science.gov (United States)

    Lindell, Annukka K.

    2017-01-01

    Painted and photographic portraits of others show an asymmetric bias: people favor their left cheek. Both experimental and database studies confirm that the left cheek bias extends to selfies. To date all such selfie studies have been cross-sectional; whether individual selfie-takers tend to consistently favor the same pose orientation, or switch between multiple poses, remains to be determined. The present study thus examined intra-individual consistency in selfie pose orientations. Two hundred selfie-taking participants (100 male and 100 female) were identified by searching #selfie on Instagram. The most recent 10 single-subject selfies for the each of the participants were selected and coded for type of selfie (normal; mirror) and pose orientation (left, midline, right), resulting in a sample of 2000 selfies. Results indicated that selfie-takers do tend to consistently adopt a preferred pose orientation (α = 0.72), with more participants showing an overall left cheek bias (41%) than would be expected by chance (overall right cheek bias = 31.5%; overall midline bias = 19.5%; no overall bias = 8%). Logistic regression modellng, controlling for the repeated measure of participant identity, indicated that sex did not affect pose orientation. However, selfie type proved a significant predictor when comparing left and right cheek poses, with a stronger left cheek bias for mirror than normal selfies. Overall, these novel findings indicate that selfie-takers show intra-individual consistency in pose orientation, and in addition, replicate the previously reported left cheek bias for selfies and other types of portrait, confirming that the left cheek bias also presents within individuals’ selfie corpora. PMID:28270790

  8. A Shocking Solar Nebula?

    OpenAIRE

    Liffman, Kurt

    2009-01-01

    It has been suggested that shock waves in the solar nebula formed the high temperature materials observed in meteorites and comets. It is shown that the temperatures at the inner rim of the solar nebula could have been high enough over a sufficient length of time to produce chondrules, CAIs, refractory dust grains and other high-temperature materials observed in comets and meteorites. The solar bipolar jet flow may have produced an enrichment of 16O in the solar nebula over time and the chond...

  9. Solar thermal barometer

    International Nuclear Information System (INIS)

    Anon.

    2004-01-01

    After the bad year of 2002, the european solar thermal market returned to double-digit growth rate in 2003: 22%. Nevertheless, the sector still has not recovered the growth rate it had in the early 2000 and European Commission targets are still far from being reached. This paper presents the thermal solar industry barometer. Data on the evolution of annually installed surfaces in the european union since 1993, the cumulated capacity of thermal collectors installed in the European Union, the estimation of the annual energy production associated to european solar thermal capacities and the main companies of the European Union thermal solar sector are presented and discussed. (A.L.B.)

  10. Rectenna solar cells

    CERN Document Server

    Moddel, Garret

    2013-01-01

    Rectenna Solar Cells discusses antenna-coupled diode solar cells, an emerging technology that has the potential to provide ultra-high efficiency, low-cost solar energy conversion. This book will provide an overview of solar rectennas, and provide thorough descriptions of the two main components: the diode, and the optical antenna. The editors discuss the science, design, modeling, and manufacturing of the antennas coupled with the diodes. The book will provide concepts to understanding the challenges, fabrication technologies, and materials required to develop rectenna structures. Written by e

  11. Solar neutrino experiments

    International Nuclear Information System (INIS)

    Hampel, W.

    1996-01-01

    The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial 51 Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs

  12. Solar Hydrogen Reaching Maturity

    Directory of Open Access Journals (Sweden)

    Rongé Jan

    2015-09-01

    Full Text Available Increasingly vast research efforts are devoted to the development of materials and processes for solar hydrogen production by light-driven dissociation of water into oxygen and hydrogen. Storage of solar energy in chemical bonds resolves the issues associated with the intermittent nature of sunlight, by decoupling energy generation and consumption. This paper investigates recent advances and prospects in solar hydrogen processes that are reaching market readiness. Future energy scenarios involving solar hydrogen are proposed and a case is made for systems producing hydrogen from water vapor present in air, supported by advanced modeling.

  13. The inconstant solar constant

    International Nuclear Information System (INIS)

    Willson, R.C.; Hudson, H.

    1984-01-01

    The Active Cavity Radiometer Irradiance Monitor (ACRIM) of the Solar Maximum Mission satellite measures the radiant power emitted by the sun in the direction of the earth and has worked flawlessly since 1980. The main motivation for ACRIM's use to measure the solar constant is the determination of the extent to which this quantity's variations affect earth weather and climate. Data from the solar minimum of 1986-1987 is eagerly anticipated, with a view to the possible presence of a solar cycle variation in addition to that caused directly by sunspots

  14. CERN... Solar Style

    CERN Multimedia

    2001-01-01

    Inventor William van Sprolant presenting the Solar Club's latest invention, the solar fountain. The CERN Solar Club is giving new meaning to the phrase 'fun in the sun' with their most recently developed contraption, the Solar Fountain. The Fountain was presented to the public just outside of Restaurant 1 on Wednesday October, 17th and uses solar energy to run a water pump at its base to propel a golden plastic ball up into the air. As lovely as the fountain is, the funny thing about it is that the height of the water jet and the ball are an artistic method of measuring the amount of solar power being captured by the photovoltaique panel (no batteries included). The day it was presented started out cloudy, but as the afternoon wore on, the weather brightened and the fountain jumped to life. William van Sprolant, the Solar Fountain's inventor, had great fun with the fountain in front of a group of visiting children swiveling the solar panel in multiple directions. 'Everyone who installs solar panels worrie...

  15. Solar Stereoscopy and Tomography

    Directory of Open Access Journals (Sweden)

    Markus J. Aschwanden

    2011-10-01

    Full Text Available We review stereoscopic and tomographic methods used in the solar corona, including ground-based and space-based measurements, using solar rotation or multiple spacecraft vantage points, in particular from the STEREO mission during 2007--2010. Stereoscopic and tomographic observations in the solar corona include large-scale structures, streamers, active regions, coronal loops, loop oscillations, acoustic waves in loops, erupting filaments and prominences, bright points, jets, plumes, flares, CME source regions, and CME-triggered global coronal waves. Applications in the solar interior (helioseismic tomography and reconstruction and tracking of CMEs from the outer corona and into the heliosphere (interplanetary CMEs are not included.

  16. Solar Cooker Technological Change

    DEFF Research Database (Denmark)

    Ahmad, Bashir

    1997-01-01

    The challenges which solar cooking technology is facing right now is discussed. Based on a field study in Madras and Gujarat, it is asserted that there is an important incompatibility between the technology and the every day real-life conditions of the "users" of solar cooker. An evaluation report...... on a solar cooker technology in Burkina Faso supports the findings of the study. It is concluded that the users and other important actors have to be incorporated in the technological development process of solar cookers in the future....

  17. Harnessing solar heat

    CERN Document Server

    Norton, Brian

    2013-01-01

    Systems engineered by man to harness solar heat in a controlled manner now include a diverse range of technologies each serving distinctive needs in particular climate contexts. This text covers the breadth of solar energy technologies for the conversion of solar energy to provide heat, either as the directly-used output or as an intermediary to other uses such as power generation or cooling. It is a wholly updated, extended and revised version of “Solar Energy Thermal Technology” first published in 1992. The text draws on the own author’s research and that of numerous colleagues and

  18. Solar thermal in France

    International Nuclear Information System (INIS)

    Letz, T.

    2006-01-01

    This article gives details of Plan Soleil established in 2000 by the French Agency for Environment and Energy Management and its identification of solar hot water systems and combined domestic solar hot water and space heating as promising sectors for development. The setting up of a support scheme for investment by Plan Soleil is discussed along with subsidies and grants, manufacturers and importers, the guarantee of solar results, and the quality of plants, components, and installers. The costs of thermal solar equipment, and results of the French assessment programme are considered. The need for quality standards is stressed

  19. Solar energy storage

    CERN Document Server

    Sorensen, Bent

    2015-01-01

    While solar is the fastest-growing energy source in the world, key concerns around solar power's inherent variability threaten to de-rail that scale-up . Currently, integration of intermittent solar resources into the grid creates added complication to load management, leading some utilities to reject it altogether, while other operators may penalize the producers via rate increases or force solar developers to include storage devices on-site to smooth out power delivery at the point of production. However these efforts at mitigation unfold, it is increasingly clear to parties on all sides th

  20. Solar neutrino experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hampel, W [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany)

    1996-11-01

    The present status of experimental solar neutrino research is reviewed. Updated results from the Homestake, Kamiokande, GALLEX and SAGE detectors all show a deficit when compared to recent standard solar model calculations. Two of these detectors, GALLEX and SAGE, have recently been checked with artificial {sup 51}Cr neutrino sources. It is shown that astrophysical scenarios to solve the solar neutrino problems are not favoured by the data. There is hope that the results of forthcoming solar neutrino experiments can provide the answers to the open questions. (author) 6 figs., 3 tabs., 36 refs.

  1. Long Island Solar Farm

    Energy Technology Data Exchange (ETDEWEB)

    Anders, R.

    2013-05-01

    The Long Island Solar Farm (LISF) is a remarkable success story, whereby very different interest groups found a way to capitalize on unusual circumstances to develop a mutually beneficial source of renewable energy. The uniqueness of the circumstances that were necessary to develop the Long Island Solar Farm make it very difficult to replicate. The project is, however, an unparalleled resource for solar energy research, which will greatly inform large-scale PV solar development in the East. Lastly, the LISF is a superb model for the process by which the project developed and the innovation and leadership shown by the different players.

  2. Solar and interplanetary disturbances

    CERN Document Server

    Alurkar, S K

    1997-01-01

    Over the last three decades, a spate of solar wind observations have been made with sophisticated ground-based and space-borne instruments. Two highly successful space missions of the Skylab and the twin spacecraft Helios 1 and 2 have amassed an invaluable wealth of information on the large scale structure of the inner heliosphere, the solar and interplanetary magnetic field, coronal holes, interplanetary dust, solar windflows, etc.Solar and interplanetary propagating phenomena have been extensively studied during the last two decades. Very recently, a new simple model based on results from a

  3. Passive solar technology

    Energy Technology Data Exchange (ETDEWEB)

    Watson, D

    1981-04-01

    The present status of passive solar technology is summarized, including passive solar heating, cooling and daylighting. The key roles of the passive solar system designer and of innovation in the building industry are described. After definitions of passive design and a summary of passive design principles are given, performance and costs of passive solar technology are discussed. Passive energy design concepts or methods are then considered in the context of the overall process by which building decisions are made to achieve the integration of new techniques into conventional design. (LEW).

  4. Construction of the Advanced Technology Solar Telescope

    Science.gov (United States)

    Rimmele, T. R.; Keil, S.; McMullin, J.; Knölker, M.; Kuhn, J. R.; Goode, P. R.; Rosner, R.; Casini, R.; Lin, H.; Tritschler, A.; Wöger, F.; ATST Team

    2012-12-01

    The 4m Advance Technology Solar Telescope (ATST) will be the most powerful solar telescope and the world's leading ground-based resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun's output. The project has entered its construction phase. Major subsystems have been contracted. As its highest priority science driver ATST shall provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona at infrared wavelengths. With its 4m aperture, ATST will resolve features at 0.″03 at visible wavelengths and obtain 0.″1 resolution at the magnetically highly sensitive near infrared wavelengths. A high order adaptive optics system delivers a corrected beam to the initial set of state-of-the-art, facility class instrumentation located in the Coudé laboratory facility. The initial set of first generation instruments consists of five facility class instruments, including imagers and spectro-polarimeters. The high polarimetric sensitivity and accuracy required for measurements of the illusive solar magnetic fields place strong constraints on the polarization analysis and calibration. Development and construction of a four-meter solar telescope presents many technical challenges, including thermal control of the enclosure, telescope structure and optics and wavefront control. A brief overview of the science goals and observational requirements of the ATST will be given, followed by a summary of the design status of the telescope and its instrumentation, including design status of major subsystems, such as the telescope mount assembly, enclosure, mirror assemblies, and wavefront correction

  5. Status of solar desalination in India

    Energy Technology Data Exchange (ETDEWEB)

    Arjunan, T.V. [Mechanical Engineering Department, Adhiyamaan College of Engineering, Hosur, Krishnagiri 635109, Tamilnadu (India); Aybar, H.S. [Mechanical Engineering Department, Eastern Mediterranean University, G. Magosa, KKTC, Mersin 10 (Turkey); Nedunchezhian, N. [Automobile Engineering, Institute of Road and Transport Technology, Erode, Tamilnadu (India)

    2009-12-15

    The work was motivated by the increasing awareness of the need for enhancing water supplies schemes in arid lands featuring an appropriate technology for solar energy use in the desalination field in India. The fresh water crisis is already evident in many parts of India, varying in scale and intensity at different times of the year. India's rapidly rising population and changing lifestyles also increases the need for fresh water. Fresh water is increasingly taking centre stage on the economic and political agenda, as more and more disputes between and within states, districts, regions, and even at the community level arises. The conventional desalination technologies like multi stage flash, multiple effect, vapor compression, iron exchange, reverse osmosis, electro dialysis are expensive for the production of small amount of fresh water, also use of conventional energy sources has a negative impact on the environment. Solar distillation represents a most attractive and simple technique among other distillation processes, and it is especially suited to small-scale units at locations where solar energy is considerable. India, being a tropical country is blessed with plenty of sunshine. The average daily solar radiation varies between 4 and 7 kWh per square meter for different parts of the country. There are on an average 250-300 clear sunny days in a year, thus it receives about 5000 trillion kWh of solar energy in a year. In spite of the limitations of being a dilute source and intermittent in nature, solar energy has the potential for meeting and supplementing various energy requirements. Solar energy systems being modular in nature could be installed in any capacity as per the requirement. This paper consists of an overall review and technical assessments of various passive and active solar distillation developments in India. This review also recommended some research areas in this field leading to high efficiency are highlighted. (author)

  6. Solar shading how to integrate solar shading in sustainable buildings

    CERN Document Server

    Dolmans, Dick; Dutoo, Gonzague; Hall, Anders; Seppänen, Olli

    2010-01-01

    Solar Shading Guidebook gives a solid background on the physics of solar radiation and its behaviour in window with solar shading systems. Major focus of the Guidebook is on the effect of solar shading in the use of energy for cooling, heating and lighting. The book gives also practical guidance for selection, installation and operation of solar shading as well as future trends in integration of HVAC-systems with solar control.

  7. Design progress of the solar UV-Vis-IR telescope (SUVIT) aboard SOLAR-C

    Science.gov (United States)

    Katsukawa, Y.; Ichimoto, K.; Suematsu, Y.; Hara, H.; Kano, R.; Shimizu, T.; Matsuzaki, K.

    2013-09-01

    We present a design progress of the Solar UV-Vis-IR Telescope (SUVIT) aboard the next Japanese solar mission SOLAR-C. SUVIT has an aperture diameter of ~1.4 m for achieving spectro-polarimetric observations with spatial and temporal resolution exceeding the Hinode Solar Optical Telescope (SOT). We have studied structural and thermal designs of the optical telescope as well as the optical interface between the telescope and the focal plane instruments. The focal plane instruments are installed into two packages, filtergraph and spectrograph packages. The spectropolarimeter is the instrument dedicated to accurate polarimetry in the three spectrum windows at 525 nm, 854 nm, and 1083 nm for observing magnetic fields at both the photospheric and chromospheric layers. We made optical design of the spectrograph accommodating the conventional slit spectrograph and the integral field unit (IFU) for two-dimensional coverage. We are running feasibility study of the IFU using fiber arrays consisting of rectangular cores.

  8. How the relative permittivity of solar cell materials influences solar cell performance

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Huss-Hansen, Mathias K.; Hansen, Ole

    2017-01-01

    of the materials permittivity on the physics and performance of the solar cell by means of numerical simulation supported by analytical relations. We demonstrate that, depending on the specific solar cell configuration and materials properties, there are scenarios where the relative permittivity has a major......The relative permittivity of the materials constituting heterojunction solar cells is usually not considered as a design parameter when searching for novel combinations of heterojunction materials. In this work, we investigate the validity of such an approach. Specifically, we show the effect...... the heterojunction partner has a high permittivity, solar cells are consistently more robust against several non-idealities that are especially likely to occur in early-stage development, when the device is not yet optimized....

  9. Parameterization models for solar radiation and solar technology applications

    International Nuclear Information System (INIS)

    Khalil, Samy A.

    2008-01-01

    Solar radiation is very important for the evaluation and wide use of solar renewable energy systems. The development of calibration procedures for broadband solar radiation photometric instrumentation and the improvement of broadband solar radiation measurement accuracy have been done. An improved diffuse sky reference and photometric calibration and characterization software for outdoor pyranometer calibrations are outlined. Parameterizations for direct beam, total hemispherical and diffuse sky radiation and solar radiation technology are briefly reviewed. The uncertainties for various broadband solar radiations of solar energy and atmospheric effects are discussed. The varying responsivities of solar radiation with meteorological, statistical and climatological parameters and possibility atmospheric conditions was examined

  10. Parameterization models for solar radiation and solar technology applications

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, Samy A. [National Research Institute of Astronomy and Geophysics, Solar and Space Department, Marsed Street, Helwan, 11421 Cairo (Egypt)

    2008-08-15

    Solar radiation is very important for the evaluation and wide use of solar renewable energy systems. The development of calibration procedures for broadband solar radiation photometric instrumentation and the improvement of broadband solar radiation measurement accuracy have been done. An improved diffuse sky reference and photometric calibration and characterization software for outdoor pyranometer calibrations are outlined. Parameterizations for direct beam, total hemispherical and diffuse sky radiation and solar radiation technology are briefly reviewed. The uncertainties for various broadband solar radiations of solar energy and atmospheric effects are discussed. The varying responsivities of solar radiation with meteorological, statistical and climatological parameters and possibility atmospheric conditions was examined. (author)

  11. Surface Meteorology and Solar Energy

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface Meteorology and Solar Energy data - over 200 satellite-derived meteorology and solar energy parameters, monthly averaged from 22 years of data, global solar...

  12. Make Your Own Solar Panel.

    Science.gov (United States)

    Suzuki, David

    1992-01-01

    Presents an activity in which students make a simulated solar panel to learn about the principles behind energy production using solar panels. Provides information about how solar panels function to produce energy. (MCO)

  13. An equatorial coronal hole at solar minimum

    Science.gov (United States)

    Bromage, B. J. I.; DelZanna, G.; DeForest, C.; Thompson, B.; Clegg, J. R.

    1997-01-01

    The large transequatorial coronal hole that was observed in the solar corona at the end of August 1996 is presented. It consists of a north polar coronal hole called the 'elephant's trunk or tusk'. The observations of this coronal hole were carried out with the coronal diagnostic spectrometer onboard the Solar and Heliospheric Observatory (SOHO). The magnetic field associated with the equatorial coronal hole is strongly connected to that of the active region at its base, resulting in the two features rotating at almost the same rate.

  14. Testing relativity with solar system dynamics

    Science.gov (United States)

    Hellings, R. W.

    1984-01-01

    A major breakthrough is described in the accuracy of Solar System dynamical tests of relativistic gravity. The breakthrough was achieved by factoring in ranging data from Viking Landers 1 and 2 from the surface of Mars. Other key data sources included optical transit circle observations, lunar laser ranging, planetary radar, and spacecraft (Mariner 9 to Mars and Mariner 10 to Mercury). The Solar System model which is used to fit the data and the process by which such fits are performed are explained and results are discussed. The results are fully consistent with the predictions of General Relativity.

  15. Solar: California, not dreaming

    Energy Technology Data Exchange (ETDEWEB)

    Jones, J.

    2006-03-15

    The California Solar Initiative (CSI) was approved by the California Public Utilities Commission (PUC) in January 2006. The CSI is the largest solar programme of this kind ever in the USA and provides for $3.2 billion in incentives for solar projects between 2007 and 2017. The PUC will oversee a $2.5 billion programme to provide funding for solar installations on commercial and existing residential buildings, while the California Energy Commission (CEC) will manage a separate $350 million fund targeted at new residential building. Existing solar programmes operated by the PUC and CEC will be consolidated into the CSI. The CEC programme will use already allocated funding, but the PUC programme will be funded through revenues collected from customers of the main gas and electric utilities in California. Funds will be distributed via rebates to householders or companies that install solar. As well as solar photovoltaics (PV), rebates will also go to solar thermal power (concentrating solar power) and solar heating and cooling. CSI funding can be used in combination with existing federal tax credits. The aim is a gradual increase from installation of 40 MW of PV in 2005 to 100 MW by 2009. The CSI is also expected to create favourable market conditions for PV manufacturers in California and to encourage investment in production of solar-grade silicon in or near California. Objections from the International Brotherhood of Electrical Workers (IBEW) appear to have been overcome but a number of other potential snags remain. CSI is expected to be replicated in other US states.

  16. Spectrally selective solar energy materials

    International Nuclear Information System (INIS)

    Sikkens, M.

    1981-01-01

    The performance and properties of spectrally selective materials are considered and, in particular, the selective absorption of solar radiation by free electrons is discussed, both in a homogeneous material in which these electrons are strongly scattered, and in a composite material consisting of small metal particles in a dielectric host. Such materials can be used as selective absorbers if they are deposited as a thin film onto a metal substrate, the latter providing the required low emittance. This type of selective surfaces is produced by reactive sputtering of Ni in an Ar/CH 4 gas mixture. This method can yield Ni films with a considerable carbon concentration. The carbon concentration can be varied over a wide range by adjusting the partial methane pressure. The associated experimental techniques are discussed. As the carbon concentration increases, the structure of the films changes from a Ni phase in which carbon is dissolved, via an intermediate Ni 3 C phase into an amorphous carbon phase with a high electrical resistivity in which small nickel particles are embedded. Both mechanisms of selective absorption by free electrons are observed and are found to be well described by rather simple models. The best selectivity is obtained at high carbon concentrations where the films consist of nickel particles in carbon. Depending on the film thickness and the substrate material, the solar absorptance varies between 0.78 and 0.90, while the thermal emittance varies between 0.025 and 0.04. Since the films are found to be stable at 400 0 C in vacuum, it appears that these films are good candidates for application in photothermal solar energy conversion at temperature levels around 200 0 C and higher. (Auth.)

  17. The solarPACES strategy for the solar thermal breakthrough

    International Nuclear Information System (INIS)

    Burch, G.D.; Grasse, W.

    1997-01-01

    IEA(International Energy Agency)/SolarPACES(Solar Power and Chemical Energy systems)represents a world wide coalition for information sharing and collaboration on applications of concentrated solar energy. The current SolarPACES community has built up solar thermal system know-how over 15 years, is operating the three main solar test centres in the world. Its main activities are in the following four fields: solar thermal electric power systems, solar chemistry, solar technology and advanced applications and non-technical activities. The article presents the talk on the strategy of solarPACES given at the International Workshop on applied solar energy held in Tashkent(Uzbekistan) in June 1997. (A.A.D.)

  18. Solar air conditioning. Dresden colloquium; Solare Klimatisierung. Dresdner Kolloquium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    Subjects: R + D activities in solar air conditioning; dessicative and evaporative cooling (DEC) - systems and components; Chances of solar air conditioning in Europe; Practical experience with solar-assisted air conditioning; Performance of a solar system at Lissabon; DEC system in the Alsenblock building, Berlin; Does solar air conditioning require specially designed buildings; Performance of solar heated adsorption refrigerators; Low-capacity absacity absorption systems for solar air conditioning. [German] Die Kolloquiumsschrift beinhaltet Unterlagen ueber die abgehandelten Themen. Sie lauten: F and E-Aktivitaeten im Bereich Solare Klimatisierung; SGK(DEC-Technik) - ausgefuehrte Anlagen und deren Komponenten; Chancen der solaren Klimatisierung in Europa; Erfahrungen mit der solarunterstuetzten Klimatisierung; Energieverbrauch und Regelung von SGK-Anlagen; Betriebserfahrungen einer Solaranlage in Lissabon; Realisierung der SGK im Alsenblock Berlin; Erfordert die solare Klimatisierung besondere Gebaeude?; Betriebserfahrungen mit solar beheizten Adsorptionskaeltemaschinen; Absorptionsanlagen kleiner Leistung fuer solare Klimatisierung. (orig.)

  19. Solar absorption cooling

    NARCIS (Netherlands)

    Kim, D.S.

    2007-01-01

    As the world concerns more and more on global climate changes and depleting energy resources, solar cooling technology receives increasing interests from the public as an environment-friendly and sustainable alternative. However, making a competitive solar cooling machine for the market still

  20. The lower solar atmosphere

    NARCIS (Netherlands)

    Rutten, R.J.

    1998-01-01

    This "rapporteur" report discusses the solar photosphere and low chromosphere in the context of chemical composition studies. The highly dynamical nature of the photosphere does not seem to jeopardize precise determination of solar abundances in classical fashion. It is still an open question how

  1. Solar Energy: Heat Storage.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  2. Priority to solar energy

    International Nuclear Information System (INIS)

    Berner, Joachim

    2011-01-01

    There are many different combinations of solar heating systems and heat pumps in the market; some of them differ considerably in terms of the design concept, control management and storage technology. One thing they all have in common is that solar heating comes first.

  3. Solar thermal power plants

    International Nuclear Information System (INIS)

    Schnatbaum, L.

    2009-01-01

    The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale. In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of the collector. The thermal energy thus generated is used for electricity generation in a steam turbine. Parabolic trough plants can be combined with thermal storage and fossil or biomass fired heat exchangers to generate electricity even when the sun is not shining. Solar Millennium AG in Erlangen has developed the first power plant of this kind in Europe. After two years of construction the plant started operation in Southern Spain in 2008. This one and its sister projects are important steps leading the way for the whole market. The paper also covers the technological challenges, the key components used and the research and development activities concerning this technology. Solar thermal power plants are ideal for covering peak and medium loads in power grids. In hybrid operation they can also cover base-load. The Solar Chimney power plant, another striking technology for the conversion of solar into electric energy, is described briefly. The paper concludes with a look at the future - the import of solar energy from the deserts of North Africa to central Europe. (author)

  4. Sunmotor Solar Shack 120

    International Nuclear Information System (INIS)

    Jensen, E.

    2009-01-01

    This article described a solar pump that was developed by Alberta-based Sunmotor International Ltd. The prototype Solar Shack 120 was recently deployed in central Alberta for a remediation project for Devon Canada. The portable solar pump unit is well suited for environmental remediation in the oilpatch where conventional electricity is not available. The solar panels automatically run the pump whenever there is enough sunlight and there is liquid in the sump. Devon Canada wanted a system that continues to pump during cloudy weather to avoid the accumulation of effluent in the sump. The Solar Shack 120 delivers 120 volts of alternating current (vac) power. Solar panels are used to charge a bank of large sealed batteries that supply direct power (DC) to an inverter, which converts it into AC. A thermostat control was added to shut off the pumps in cold weather to avoid battery discharging. The Solar Shack unit has possibilities in countries with unreliable electricity supplies. It could provide a backup power supply that automatically kicks in whenever the power grid goes down. Sunmotor International Ltd. can supply complete remote power systems for both AC and DC electrical requirements. The systems are designed for each application to ensure customer satisfaction. The company is currently building a unit that integrates solar power with a generator backup, thereby eliminating the annoying noise of a continually running generator. 1 fig

  5. Solar Environmental Disturbances

    Science.gov (United States)

    2007-11-02

    Astronomische Nachrichten 324, 303-304: Design and Development of the Advanced Technology Solar Telescope Keller, C.U., Rimmele, T.R., Hill, F...Keil, S.L., Oschmann, J.M., and the ATST Team 2002, Astronomische Nachrichten 323, 294-298: The Advanced Technology Solar Telescope Mozer, J.B

  6. Solar energy in Peru

    Energy Technology Data Exchange (ETDEWEB)

    Pierson, H.

    1981-12-01

    The past, present, and future of Peru is discussed in terms of solar energy development and the social, economic, climatic, and technical factors involved. It is pointed out that there are 3 geographical divisions in Peru including: (1) the foggy coastal strip where rain is infrequent, insolation is low and population is high; (2) the mountainous Andes region with high insolation and many populated high mountain valleys; and (3) the rainy, Amazon basin covered with jungle, and sparcely populated with high but inconsistent insolation. Since there is little competition with other forms of energy, solar energy shows promise. Passive solar heating of buildings, particularly in the Andes region, is described, as well as the use of solar water heaters. Prototypes are described and illustrated. Industrial use of solar heated water in the wool industry as well as solar food drying and solar desalination are discussed. High temperature applications (electrical generators and refrigeration) as well as photovoltaic systems are discussed briefly. It is concluded that social and political factors are holding back the development of solar energy but a start (in the form of prototypes and demonstration programs) is being made. (MJJ)

  7. Solar Electricity for Homes

    Science.gov (United States)

    Roman, Harry T.

    2012-01-01

    Every day, the sun showers the Earth with millions of times more energy than its people use. The only problem is that energy is spread out over the entire Earth's surface and must be harvested. Engineers are learning to capture and use some of this energy to make electricity for homes. Solar panels make up the heart of a solar system. They can be…

  8. Probing the Solar Interior

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 3. Probing the Solar Interior Hearing the Heartbeats of the Sun. Ashok Ambastha. General ... Author Affiliations. Ashok Ambastha1. Joint In-Charge Udaipur Solar Observatory Physical Research laboratory P.O. Box No. 198 Udaipur 313 001, India ...

  9. Energetic solar particles

    International Nuclear Information System (INIS)

    Biswas, M.

    1975-01-01

    In this review, some of the important aspects of energetic solar particles and their relation to solar physics are discussed. The major aspects of solar cosmic ray studies currently under investigation are identified and attention is focussed on the problems of the physical processes in the sun which may be responsible for these phenomena. The studies of the composition and energy spectra of solar cosmic ray nuclei are related to the basic problem of particle acceleration process in sun and to the composition of elements in solar atmosphere. The composition of higher energy (>20 MeV/amu) multiply charged nuclei of He, C, N, O, Ne, Mg, Si and Fe give information on the abundance of elements in the solar atmosphere. At lower energies (approximately 1-10 MeV/amu), the abundances of these elements show enhancements relative to solar abundances and these enhancements are believed to be due to particle acceleration mechanisms operative in the sun which are not fully understood at present. Studies of the relative abundances of H 2 , H 3 and He 3 isotopes and Li, Be, B nuclei in the solar cosmic rays can also be studied. The question of the relationship of the accelerated particles in the sun to the optical flare phenomena is discussed. Further studies of different aspects of these phenomena may give important clues to a wide ranging phenomena in the active sun. The observational methods employed for these studies are mentioned. (A.K.)

  10. The Solar Energy Notebook.

    Science.gov (United States)

    Rankins, William H., III; Wilson, David A.

    This publication is a handbook for the do-it-yourselfer or anyone else interested in solar space and water heating. Described are methods for calculating sun angles, available energy, heating requirements, and solar heat storage. Also described are collector and system designs with mention of some design problems to avoid. Climatological data for…

  11. Homemade Solar Systems

    Science.gov (United States)

    1981-01-01

    Through the use of NASA Tech Briefs, Peter Kask, was able to build a solarized domestic hot water system. Also by applying NASA's solar energy design information, he was able to build a swimming pool heating system with minimal outlay for materials.

  12. Solar collector overheating protection

    NARCIS (Netherlands)

    Slaman, M.J.; Griessen, R.P.

    Prismatic structures in a thermal solar collector are used as overheating protection. Such structures reflect incoming light efficiently back whenever less thermal power is extracted from the solar collector. Maximum thermal power is generated when the prismatic structure is surrounded by a

  13. On the Solar oblateness

    International Nuclear Information System (INIS)

    Kislik, M.D.

    1983-01-01

    Limits for the magnitude of Solar oblateness under the assumption that the Sun is rotating as a rigid body with the velocity of sideric rotation of the equator points have been determined. It is demonstrated that for the present there is no necessity to take into accoUnt Solar oblateness when making the interior planets movement theories

  14. MEMS Solar Generators

    OpenAIRE

    Grbovic, Dragoslav; Osswald, Sebastian

    2011-01-01

    Approved for public release; distribution is unlimited Using MEMS bimaterial structures to build highly efficient solar energy generators. This is a novel approach that utilizes developments in the area of bimaterial sensors and applies them in the field of solar energy harvesting.

  15. The thermodynamic solar energy

    International Nuclear Information System (INIS)

    Rivoire, B.

    2002-04-01

    The thermodynamic solar energy is the technic in the whole aiming to transform the solar radiation energy in high temperature heat and then in mechanical energy by a thermodynamic cycle. These technic are most often at an experimental scale. This paper describes and analyzes the research programs developed in the advanced countries, since 1980. (A.L.B.)

  16. Solar panel foundation device

    Energy Technology Data Exchange (ETDEWEB)

    Hawley, W.W.

    1983-03-29

    A transportable solar panel foundation device which has a bottom member, at least one upstanding side member, and an essentially open top. The side members are angled to permit nesting of a plurality of the foundation devices, and reinforcement pads are carried by the foundation device to support legs for one or more solar panels.

  17. Polymer tandem solar cells

    NARCIS (Netherlands)

    Gilot, J.

    2010-01-01

    Solar cells convert solar energy directly into electricity and are attractive contribute to the increasing energy demand of modern society. Commercial mono-crystalline silicon based devices are infiltrating the energy market but their expensive, time and energy consuming production process

  18. Solar-powered Gossamer Penguin in flight

    Science.gov (United States)

    1979-01-01

    Gossamer Penguin in flight above Rogers Dry Lakebed at Edwards, California, showing the solar panel perpendicular to the wing and facing the sun. Background The first flight of a solar-powered aircraft took place on November 4, 1974, when the remotely controlled Sunrise II, designed by Robert J. Boucher of AstroFlight, Inc., flew following a launch from a catapult. Following this event, AeroVironment, Inc. (founded in 1971 by the ultra-light airplane innovator--Dr. Paul MacCready) took on a more ambitious project to design a human-piloted, solar-powered aircraft. The firm initially took the human-powered Gossamer Albatross II and scaled it down to three-quarters of its previous size for solar-powered flight with a human pilot controlling it. This was more easily done because in early 1980 the Gossamer Albatross had participated in a flight research program at NASA Dryden in a program conducted jointly by the Langley and Dryden research centers. Some of the flights were conducted using a small electric motor for power. Gossamer Penguin The scaled-down aircraft was designated the Gossamer Penguin. It had a 71-foot wingspan compared with the 96-foot span of the Gossamer Albatross. Weighing only 68 pounds without a pilot, it had a low power requirement and thus was an excellent test bed for solar power. AstroFlight, Inc., of Venice, Calif., provided the power plant for the Gossamer Penguin, an Astro-40 electric motor. Robert Boucher, designer of the Sunrise II, served as a key consultant for both this aircraft and the Solar Challenger. The power source for the initial flights of the Gossamer Penguin consisted of 28 nickel-cadmium batteries, replaced for the solar-powered flights by a panel of 3,920 solar cells capable of producing 541 Watts of power. The battery-powered flights took place at Shafter Airport near Bakersfield, Calif. Dr. Paul MacCready's son Marshall, who was 13 years old and weighed roughly 80 pounds, served as the initial pilot for these flights to

  19. The Solar Bank concept

    International Nuclear Information System (INIS)

    Eckhart, M.T.

    1999-01-01

    The Solar Bank is proposed to be established as a multinational wholesale lending institution supporting the adoption of solar photovoltaic (PV) systems by as much as 40% of the world's population. It would supply capital resources to local lending institutions such as banks, credit unions, cooperatives, and rural lending organizations in the developing countries, and to financial institutions in the developed countries. The Solar Bank is intended to be global in scope, with operations in the major countries. The Solar Bank will bring a degree of standardization to the process of making small loans to many people for the purchase of PV systems, and it will provide technical support and training to its participating financial institutions. 'Solar Bank International' is likely to be headquartered in Europe. (orig.)

  20. Meteorology ans solar physics

    Science.gov (United States)

    Schwarz, Oliver

    When in the second half of the 19th century both solar physics and astrophysics came into existence, various solar phenomena were described by analogies encountered in the terrestrial atmosphere. For a certain time, meteorology played a central role in research on solar processes. At first glance, this may appear as a curious and old-fashioned specialty. However, solar physics owes its first insights into solar structure to various analogies in terrestrial atmospheric studies. The present investigation intends to elucidate this fact, to present details of the historical development, and to demonstrate how our present knowledge in certain fields is based on considerations which were originally taken from the description of the terrestrial atmosphere.

  1. A Little Solar Story

    DEFF Research Database (Denmark)

    Ahmad, Bashir

    1997-01-01

    Experiences from use of solar cookers in India and many other places are different. But the story which is based on a field study in Gujarat state of India shows that during last twenty years there has been a tendency that many families do not continue to use their solar cookers. The study shows...... that the tendency is related with the lack of compatibility of this new technology (solar cooker) with the everyday real-life conditions of the families. In principle the findings are supported by an evaluation report on a solar cooker project in Burkina Faso. The conclusion is that the user should be involved...... in the solar cooker technological development process....

  2. Solar combi systems

    DEFF Research Database (Denmark)

    Andersen, Elsa

    2007-01-01

    The focus in the present Ph.D. thesis is on the active use of solar energy for domestic hot water and space heating in so-called solar combi systems. Most efforts have been put into detailed investigations on the design of solar combi systems and on devices used for building up thermal...... the thermal behaviour of different components, and the theoretical investigations are used to study the influence of the thermal behaviour on the yearly thermal performance of solar combi systems. The experimental investigations imply detailed temperature measurements and flow visualization with the Particle...... Image Velocimetry measurement method. The theoretical investigations are based on the transient simulation program TrnSys and Computational Fluid Dynamics. The Ph.D. thesis demonstrates the influence on the thermal performance of solar combi systems of a number of different parameters...

  3. Development of an Embedded Solar Tracker using Compact RIO

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Seung Jin; Lee, Yoon Joon; Chun, Won Gee [Jeju National University, Jeju (Korea, Republic of)

    2011-08-15

    An embedded two-axis solar tracking system using LabVIEW to write the operation and control algorithms was developed for enhancing solar energy utilization. The system consists of a real-time processor, two motion- control modules, two step drives, two step motors, feedback devices, and other accessories needed for functional stability. The real-time processor allows the solar tracker to be used as a stand-alone, real-time system that can operate automatically without any external control. The system combines two different solar tracking methods: the optical method and the astronomical method. CdS sensors are employed to continuously generate feedback signals to the controller, ensuring high-precision solar tracking even under adverse conditions. CdS sensor is a resistor whose resistance decreases with increasing incident light intensity. A database of solar altitude, azimuth, and sunrise and sunset times is provided by this solar tracking system. Other solar trackers operating in an astronomical method may access and use this database over the Internet. Solar position and sunrise and sunset times in the database were compared with those of the Astronomical Applications Department of the U.S. Naval Observatory. The differences were found to be negligible.

  4. Development of an Embedded Solar Tracker using Compact RIO

    International Nuclear Information System (INIS)

    Oh, Seung Jin; Lee, Yoon Joon; Chun, Won Gee

    2011-01-01

    An embedded two-axis solar tracking system using LabVIEW to write the operation and control algorithms was developed for enhancing solar energy utilization. The system consists of a real-time processor, two motion- control modules, two step drives, two step motors, feedback devices, and other accessories needed for functional stability. The real-time processor allows the solar tracker to be used as a stand-alone, real-time system that can operate automatically without any external control. The system combines two different solar tracking methods: the optical method and the astronomical method. CdS sensors are employed to continuously generate feedback signals to the controller, ensuring high-precision solar tracking even under adverse conditions. CdS sensor is a resistor whose resistance decreases with increasing incident light intensity. A database of solar altitude, azimuth, and sunrise and sunset times is provided by this solar tracking system. Other solar trackers operating in an astronomical method may access and use this database over the Internet. Solar position and sunrise and sunset times in the database were compared with those of the Astronomical Applications Department of the U.S. Naval Observatory. The differences were found to be negligible

  5. Optical study of solar tower power plants

    International Nuclear Information System (INIS)

    Eddhibi, F; Amara, M Ben; Balghouthi, M; Guizani, A

    2015-01-01

    The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature

  6. Recent developments in luminescent solar concentrators

    Science.gov (United States)

    van Sark, W. G. J. H. M.

    2014-10-01

    High efficiency photovoltaic devices combine full solar spectrum absorption and effective generation and collection of charge carriers, while commercial success depends on cost effectiveness in manufacturing. Spectrum modification using down shifting has been demonstrated in luminescent solar concentrators (LSCs) since the 1970s, as a cheap alternative for standard c-Si technology. LSCs consist of a highly transparent plastic plate, in which luminescent species are dispersed, which absorb incident light and emit light at a red-shifted wavelength, with high quantum efficiency. Material issues have hampered efficiency improvements, in particular re-absorption of light emitted by luminescent species and stability of these species. In this contribution, approaches are reviewed on minimizing re-absorption, which should allow surpassing the 10% luminescent solar concentrator efficiency barrier.

  7. Embracing Open Software Development in Solar Physics

    Science.gov (United States)

    Hughitt, V. K.; Ireland, J.; Christe, S.; Mueller, D.

    2012-12-01

    We discuss two ongoing software projects in solar physics that have adopted best practices of the open source software community. The first, the Helioviewer Project, is a powerful data visualization tool which includes online and Java interfaces inspired by Google Maps (tm). This effort allows users to find solar features and events of interest, and download the corresponding data. Having found data of interest, the user now has to analyze it. The dominant solar data analysis platform is an open-source library called SolarSoft (SSW). Although SSW itself is open-source, the programming language used is IDL, a proprietary language with licensing costs that are prohibative for many institutions and individuals. SSW is composed of a collection of related scripts written by missions and individuals for solar data processing and analysis, without any consistent data structures or common interfaces. Further, at the time when SSW was initially developed, many of the best software development processes of today (mirrored and distributed version control, unit testing, continuous integration, etc.) were not standard, and have not since been adopted. The challenges inherent in developing SolarSoft led to a second software project known as SunPy. SunPy is an open-source Python-based library which seeks to create a unified solar data analysis environment including a number of core datatypes such as Maps, Lightcurves, and Spectra which have consistent interfaces and behaviors. By taking advantage of the large and sophisticated body of scientific software already available in Python (e.g. SciPy, NumPy, Matplotlib), and by adopting many of the best practices refined in open-source software development, SunPy has been able to develop at a very rapid pace while still ensuring a high level of reliability. The Helioviewer Project and SunPy represent two pioneering technologies in solar physics - simple yet flexible data visualization and a powerful, new data analysis environment. We

  8. Solar and Hydrogen

    International Nuclear Information System (INIS)

    Kadirgan, F.; Beyhan, S.; Oezenler, S.

    2006-01-01

    It has been widely accepted that the only sustainable and environmentally friendly energy is the solar energy and hydrogen energy, which can meet the increasing energy demand in the future. Solar Energy may be used either for solar thermal or for solar electricity conversion. Solar thermal collectors represent a wide-spread type of system for the conversion of solar energy. Radiation, convection and conduction are strongly coupled energy transport mechanisms in solar collector systems. The economic viability of lower temperature applications of solar energy may be improved by increasing the quantity of usable energy delivered per unit area of collector. This can be achieved by the use of selective black coatings which have a high degree of solar absorption, maintaining high energy input to the solar system while simultaneously suppressing the emission of thermal infrared radiation. Photovoltaic solar cells and modules are produced for: (1) large scale power generation, most commonly when modules are incorporated as part of a building (building integrated photovoltaic s) but also in centralised power stations, (2) supplying power to villages and towns in developing countries that are not connected to the supply grid, e.g. for lighting and water pumping systems, (3) supplying power in remote locations, e.g. for communications or weather monitoring equipment, (4) supplying power for satellites and space vehicles, (5) supplying power for consumer products, e.g. calculators, clocks, toys and night lights. In hydrogen energy systems, Proton exchange membrane (PEMFC) fuel cells are promising candidates for applications ranging from portable power sources (battery replacement applications) to power sources for future electric vehicles because of their safety, elimination of fuel processor system, thus, simple device fabrication and low cost. Although major steps forward have been achieved in terms of PEMFC design since the onset of research in this area, further

  9. Performances of solar water pumping station with solar tracker

    International Nuclear Information System (INIS)

    Buniatyan, V.V.; Vardanyan, A.A.

    2011-01-01

    For the solar water pumping stations ? solar tracking system with phototransistor is developed. On the basis of the experimental investigations the utility and efficiency of the PV water pumping station with solar tracker under different conditions of varying solar radiation in Armenia is shown

  10. Preliminary design package for solar collector and solar pump

    Science.gov (United States)

    1978-01-01

    A solar-operated pump using an existing solar collector, for use on solar heating and cooling and hot water systems is described. Preliminary design criteria of the collector and solar-powered pump is given including: design drawings, verification plans, and hazard analysis.

  11. Solar '80s: A Teacher's Handbook for Solar Energy Education.

    Science.gov (United States)

    LaHart, David E.

    This guide is intended to assist the teacher in exploring energy issues and the technology of solar energy conversion and associated technologies. Sections of the guide include: (1) Rationale; (2) Technology Overview; (3) Sun Day Suggestions for School; (4) Backyard Solar Water Heater; (5) Solar Tea; (6) Biogas; (7) Solar Cells; (8) Economics; (9)…

  12. The Effects of Solar Irradience and Ambient Temperature on Solar ...

    African Journals Online (AJOL)

    Solar energy is abundant. It is however low grade energy and cannot be easily used in the form it occurs for work. Converting solar energy directly to electricity, using solar photovoltaic (PV) modules is however a low efficiency process. Optimizing this conversion, especially in the face of the high cost of solar panels, is thus ...

  13. Solar thermal and concentrated solar power barometer

    International Nuclear Information System (INIS)

    2013-01-01

    The European concentrated solar power plant market is steeling itself for tough time ahead. The number of projects under construction is a pittance compared with 2012 that was an excellent year for installations (an additional 802.5 MW of capacity recorded). This drop is the result of the moratorium on renewable energy power plants introduced by the Spanish government. The European solar thermal market is hardly any more encouraging . EurObserv'ER holds that it slipped for the fourth year in a row (it dropped 5.5% between 2011 and 2012). The newly-installed solar thermal collector surface area in the EU now stands at 3.4 million m 2 , far short of its 2008 installation record of 4.6 million m 2 . The EU's solar thermal base to date at the end of 2012 is 29.6 GWth with 2.4 GWth installed during the year 2012. This article gives tables gathering the figures of the production for every European country for 2012 and describes the market and the general trend for every EU member

  14. Emerging Solar Technologies: Perovskite Solar Cell

    Indian Academy of Sciences (India)

    energy technologies and ... cost-effective and feasible non-silicon solar cell technologies. ..... storing in the air for long periods, and the stability reached up to .... [12] Y Liu, L A Renna, M Bag, Z A Page, P Kim, J Choi, T Emrick, D Venkatara-.

  15. Oil fired boiler/solar tank- and natural gas burner/solar tank-units

    DEFF Research Database (Denmark)

    Furbo, Simon; Vejen, Niels Kristian; Frederiksen, Karsten Vinkler

    1999-01-01

    During the last few years new units consisting of a solar tank and either an oil fired boiler or a natural gas burner have been introduced on the Danish market. Three different marketed units - two based on a natural gas burner and one based on an oil fired boiler - have been tested in a heat...

  16. Solar Magnetism eXplorer (Solme X)

    Science.gov (United States)

    Peter, Hardi; Abbo, L.; Andretta, V.; Auchere, F.; Bemporad, A.; Berrilli, F.; Bommier, V.; Cassini, R.; Curdt, W.; Davila, J.; hide

    2011-01-01

    The magnetic field plays a pivotal role in many fields of Astrophysics. This is especially true for the physics of the solar atmosphere. Measuring the magnetic field in the upper solar atmosphere is crucial to understand the nature of the underlying physical processes that drive the violent dynamics of the solar corona-that can also affect life on Earth. SolmeX, a fully equipped solar space observatory for remote-sensing observations, will provide the first comprehensive measurements of the strength and direction of the magnetic field in the upper solar atmosphere. The mission consists of two spacecraft, one carrying the instruments, and another one in formation flight at a distance of about 200 m carrying the occulter to provide an artificial total solar eclipse. This will ensure high-quality coronagraphic observations above the solar limb. SolmeX integrates two spectro-polarimetric coronagraphs for off-limb observations, one in the EUV and one in the IR, and three instruments for observations on the disk. The latter comprises one imaging polarimeter in the EUV for coronal studies, a spectro-polarimeter in the EUV to investigate the low corona, and an imaging spectro-polarimeter in the UV for chromospheric studies. SOHO and other existing missions have investigated the emission of the upper atmosphere in detail (not considering polarization), and as this will be the case also for missions planned for the near future. Therefore it is timely that SolmeX provides the final piece of the observational quest by measuring the magnetic field in the upper atmosphere through polarimetric observations

  17. The Solar Connections Observatory for Planetary Environments

    Science.gov (United States)

    Oliversen, Ronald J.; Harris, Walter M.; Oegerle, William R. (Technical Monitor)

    2002-01-01

    The NASA Sun-Earth Connection theme roadmap calls for comparative study of how the planets, comets, and local interstellar medium (LISM) interact with the Sun and respond to solar variability. Through such a study we advance our understanding of basic physical plasma and gas dynamic processes, thus increasing our predictive capabilities for the terrestrial, planetary, and interplanetary environments where future remote and human exploration will occur. Because the other planets have lacked study initiatives comparable to the terrestrial ITM, LWS, and EOS programs, our understanding of the upper atmospheres and near space environments on these worlds is far less detailed than our knowledge of the Earth. To close this gap we propose a mission to study {\\it all) of the solar interacting bodies in our planetary system out to the heliopause with a single remote sensing space observatory, the Solar Connections Observatory for Planetary Environments (SCOPE). SCOPE consists of a binocular EUV/FUV telescope operating from a remote, driftaway orbit that provides sub-arcsecond imaging and broadband medium resolution spectro-imaging over the 55-290 nm bandpass, and high (R>10$^{5}$ resolution H Ly-$\\alpha$ emission line profile measurements of small scale planetary and wide field diffuse solar system structures. A key to the SCOPE approach is to include Earth as a primary science target. From its remote vantage point SCOPE will be able to observe auroral emission to and beyond the rotational pole. The other planets and comets will be monitored in long duration campaigns centered when possible on solar opposition when interleaved terrestrial-planet observations can be used to directly compare the response of both worlds to the same solar wind stream and UV radiation field. Using a combination of observations and MHD models, SCOPE will isolate the different controlling parameters in each planet system and gain insight into the underlying physical processes that define the

  18. Variation of the solar wind velocity following solar flares

    International Nuclear Information System (INIS)

    Huang, Y.; Lee, Y.

    1975-01-01

    By use of the superposed epoch method, changes in the solar wind velocity following solar flares have been investigated by using the solar wind velocity data obtained by Pioneer 6 and 7 and Vela 3, 4, and 5 satellites. A significant increase of the solar wind velocity has been found on the second day following importance 3 solar flares and on the third day following importance 2 solar flares. No significant increase of the solar wind velocity has been found for limb flares. (auth)

  19. Solar maximum mission

    International Nuclear Information System (INIS)

    Ryan, J.

    1981-01-01

    By understanding the sun, astrophysicists hope to expand this knowledge to understanding other stars. To study the sun, NASA launched a satellite on February 14, 1980. The project is named the Solar Maximum Mission (SMM). The satellite conducted detailed observations of the sun in collaboration with other satellites and ground-based optical and radio observations until its failure 10 months into the mission. The main objective of the SMM was to investigate one aspect of solar activity: solar flares. A brief description of the flare mechanism is given. The SMM satellite was valuable in providing information on where and how a solar flare occurs. A sequence of photographs of a solar flare taken from SMM satellite shows how a solar flare develops in a particular layer of the solar atmosphere. Two flares especially suitable for detailed observations by a joint effort occurred on April 30 and May 21 of 1980. These flares and observations of the flares are discussed. Also discussed are significant discoveries made by individual experiments

  20. Solar Hot Water Heater

    Science.gov (United States)

    1978-01-01

    The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.