WorldWideScience

Sample records for sky model presentation

  1. Sky Glow Modeling and Measurements

    Science.gov (United States)

    Davis, D.

    2004-05-01

    It is very helpful to be able to model the impact of artificial night lighting on sky glow and also to measure such sky glow in a quantitative way. Such information is needed to understand the sources of the major impacts on the sky glow and to be able to offer effective solutions. This paper will review the current work underway on both these fronts, at professional observatories, a program in the Tucson and Pima County area in Tucson, by the National Park Service, and by the International Dark-Sky Association.

  2. A Satellite-Based Sky Luminance Model for the Tropics

    Directory of Open Access Journals (Sweden)

    Serm Janjai

    2013-01-01

    Full Text Available This paper presents a sky luminance model for the tropics. The model is mathematically expressed as a multiplication of two functions. These are φ, which is a function of the zenith angle of a sky element and solar zenith angle, and f, which is a function of the angle between the sky element and the sun. To obtain the analytical forms of these functions, the sky luminance data collected at Nakhon Pathom (13.82°N, 100.04°E, Thailand, during a four-year period were analyzed. Additionally, satellite-derived cloud index at the position of the sky luminance measurements during the same period was estimated. Based on values of the cloud index, the skies were classified into 10 types, from clear to overcast skies. By using appropriate grouping and mathematical operation of the sky luminance data, the values of the two functions were obtained and then fitted with empirical equations. The multiplication of these equations gives the final form of the sky luminance model. To validate the model, it was used to calculate the relative sky luminance at other three sites in the tropics. It was found that values of relative sky luminance calculated from the model and those obtained from the measurements were in reasonable agreement.

  3. Spatial Model of Sky Brightness Magnitude in Langkawi Island, Malaysia

    Science.gov (United States)

    Redzuan Tahar, Mohammad; Kamarudin, Farahana; Umar, Roslan; Khairul Amri Kamarudin, Mohd; Sabri, Nor Hazmin; Ahmad, Karzaman; Rahim, Sobri Abdul; Sharul Aikal Baharim, Mohd

    2017-03-01

    Sky brightness is an essential topic in the field of astronomy, especially for optical astronomical observations that need very clear and dark sky conditions. This study presents the spatial model of sky brightness magnitude in Langkawi Island, Malaysia. Two types of Sky Quality Meter (SQM) manufactured by Unihedron are used to measure the sky brightness on a moonless night (or when the Moon is below the horizon), when the sky is cloudless and the locations are at least 100 m from the nearest light source. The selected locations are marked by their GPS coordinates. The sky brightness data obtained in this study were interpolated and analyzed using a Geographic Information System (GIS), thus producing a spatial model of sky brightness that clearly shows the dark and bright sky areas in Langkawi Island. Surprisingly, our results show the existence of a few dark sites nearby areas of high human activity. The sky brightness of 21.45 mag arcsec{}-2 in the Johnson-Cousins V-band, as the average of sky brightness equivalent to 2.8 × {10}-4{cd} {{{m}}}-2 over the entire island, is an indication that the island is, overall, still relatively dark. However, the amount of development taking place might reduce the number in the near future as the island is famous as a holiday destination.

  4. Global horizontal irradiance clear sky models : implementation and analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Stein, Joshua S.; Hansen, Clifford W.; Reno, Matthew J.

    2012-03-01

    Clear sky models estimate the terrestrial solar radiation under a cloudless sky as a function of the solar elevation angle, site altitude, aerosol concentration, water vapor, and various atmospheric conditions. This report provides an overview of a number of global horizontal irradiance (GHI) clear sky models from very simple to complex. Validation of clear-sky models requires comparison of model results to measured irradiance during clear-sky periods. To facilitate validation, we present a new algorithm for automatically identifying clear-sky periods in a time series of GHI measurements. We evaluate the performance of selected clear-sky models using measured data from 30 different sites, totaling about 300 site-years of data. We analyze the variation of these errors across time and location. In terms of error averaged over all locations and times, we found that complex models that correctly account for all the atmospheric parameters are slightly more accurate than other models, but, primarily at low elevations, comparable accuracy can be obtained from some simpler models. However, simpler models often exhibit errors that vary with time of day and season, whereas the errors for complex models vary less over time.

  5. A Machine-Learning-Driven Sky Model.

    Science.gov (United States)

    Satylmys, Pynar; Bashford-Rogers, Thomas; Chalmers, Alan; Debattista, Kurt

    2017-01-01

    Sky illumination is responsible for much of the lighting in a virtual environment. A machine-learning-based approach can compactly represent sky illumination from both existing analytic sky models and from captured environment maps. The proposed approach can approximate the captured lighting at a significantly reduced memory cost and enable smooth transitions of sky lighting to be created from a small set of environment maps captured at discrete times of day. The author's results demonstrate accuracy close to the ground truth for both analytical and capture-based methods. The approach has a low runtime overhead, so it can be used as a generic approach for both offline and real-time applications.

  6. The Accuracy of RADIANCE Software in Modelling Overcast Sky Condition

    OpenAIRE

    Baharuddin

    2013-01-01

    A validation study of the sky models of RADIANCE simulation software against the overcast sky condition has been carried out in order to test the accuracy of sky model of RADIANCE for modeling the overcast sky condition in Hong Kong. Two sets of data have been analysed. Firstly, data collected from a set of experiments using a physical scale model. In this experiment, the illuminance of four points inside the model was measured under real sky conditions. Secondly, the RADIANCE simulation has ...

  7. The pre-launch Planck Sky Model: a model of sky emission at submillimetre to centimetre wavelengths

    CERN Document Server

    Delabrouille, J.; Melin, J.-B.; Miville-Deschenes, M.-A.; Gonzalez-Nuevo, J.; Jeune, M.Le; Castex, G.; de Zotti, G.; Basak, S.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A.; Bernard, J.-P.; Bouchet, F.R.; Clements, D.L.; da Silva, A.; Dickinson, C.; Dodu, F.; Dolag, K.; Elsner, F.; Fauvet, L.; Fay, G.; Giardino, G.; Leach, S.; Lesgourgues, J.; Liguori, M.; Macias-Perez, J.F.; Massardi, M.; Matarrese, S.; Mazzotta, P.; Montier, L.; Mottet, S.; Paladini, R.; Partridge, B.; Piffaretti, R.; Prezeau, G.; Prunet, S.; Ricciardi, S.; Roman, M.; Schaefer, B.; Toffolatti, L.

    2012-01-01

    We present the Planck Sky Model (PSM), a parametric model for the generation of all-sky, few arcminute resolution maps of sky emission at submillimetre to centimetre wavelengths, in both intensity and polarisation. Several options are implemented to model the cosmic microwave background, Galactic diffuse emission (synchrotron, free-free, thermal and spinning dust, CO lines), Galactic H-II regions, extragalactic radio sources, dusty galaxies, and thermal and kinetic Sunyaev-Zeldovich signals from clusters of galaxies. Each component is simulated by means of educated interpolations/extrapolations of data sets available at the time of the launch of the Planck mission, complemented by state-of-the-art models of the emission. Distinctive features of the simulations are: spatially varying spectral properties of synchrotron and dust; different spectral parameters for each point source; modeling of the clustering properties of extragalactic sources and of the power spectrum of fluctuations in the cosmic infrared back...

  8. A photometric model for predicting the sky glow of greenhouses

    NARCIS (Netherlands)

    Alferdinck, J.W.A.M.; Janssen, E.G.O.N.; Zonneveldt, L.; Ruigrok, J.

    2006-01-01

    many greenhouses use artificial light to grow plants. Part of this light escapes, scatters in the sky and causes sky glow. Residents in the vicinity complain about the absence of natural darkness. A light scatter model is developed in order to quantify the dose of the sky glow. The luminance of the

  9. Sky coverage modeling for the whole sky for laser guide star multiconjugate adaptive optics.

    Science.gov (United States)

    Wang, Lianqi; Andersen, David; Ellerbroek, Brent

    2012-06-01

    The scientific productivity of laser guide star adaptive optics systems strongly depends on the sky coverage, which describes the probability of finding natural guide stars for the tip/tilt wavefront sensor(s) to achieve a certain performance. Knowledge of the sky coverage is also important for astronomers planning their observations. In this paper, we present an efficient method to compute the sky coverage for the laser guide star multiconjugate adaptive optics system, the Narrow Field Infrared Adaptive Optics System (NFIRAOS), being designed for the Thirty Meter Telescope project. We show that NFIRAOS can achieve more than 70% sky coverage over most of the accessible sky with the requirement of 191 nm total rms wavefront.

  10. Planck 2013 results. XI. All-sky model of thermal dust emission

    DEFF Research Database (Denmark)

    Abergel, A.; Ade, P. A. R.; Aghanim, N.

    2014-01-01

    This paper presents an all-sky model of dust emission from the Planck 353, 545, and 857 GHz, and IRAS 100 mu m data. Using a modified blackbody fit to the data we present all-sky maps of the dust optical depth, temperature, and spectral index over the 353-3000 GHz range. This model is a good repr...

  11. Evaluation of Clear Sky Models for Satellite-Based Irradiance Estimates

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Manajit [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gotseff, Peter [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2013-12-01

    This report describes an intercomparison of three popular broadband clear sky solar irradiance model results with measured data, as well as satellite-based model clear sky results compared to measured clear sky data. The authors conclude that one of the popular clear sky models (the Bird clear sky model developed by Richard Bird and Roland Hulstrom) could serve as a more accurate replacement for current satellite-model clear sky estimations. Additionally, the analysis of the model results with respect to model input parameters indicates that rather than climatological, annual, or monthly mean input data, higher-time-resolution input parameters improve the general clear sky model performance.

  12. Planck intermediate results XXIX. All-sky dust modelling with Planck, IRAS, and WISE observations

    DEFF Research Database (Denmark)

    Ade, P. A. R.; Aghanim, N.; Alves, M. I. R.

    2016-01-01

    We present all-sky modelling of the high resolution Planck, IRAS, andWISE infrared (IR) observations using the physical dust model presented by Draine & Li in 2007 (DL, ApJ, 657, 810). We study the performance and results of this model, and discuss implications for future dust modelling. The pres...

  13. The Python Sky Model: software for simulating the Galactic microwave sky

    Science.gov (United States)

    Thorne, B.; Dunkley, J.; Alonso, D.; Næss, S.

    2017-08-01

    We present a numerical code to simulate maps of Galactic emission in intensity and polarization at microwave frequencies, aiding in the design of cosmic microwave background experiments. This python code builds on existing efforts to simulate the sky by providing an easy-to-use interface and is based on publicly available data from the WMAP (Wilkinson Microwave Anisotropy Probe) and Planck satellite missions. We simulate synchrotron, thermal dust, free-free and anomalous microwave emission over the whole sky, in addition to the cosmic microwave background, and include a set of alternative prescriptions for the frequency dependence of each component, for example, polarized dust with multiple temperatures and a decorrelation of the signals with frequency, which introduce complexity that is consistent with current data. We also present a new prescription for adding small-scale realizations of these components at resolutions greater than current all-sky measurements. The usefulness of the code is demonstrated by forecasting the impact of varying foreground complexity on the recovered tensor-to-scalar ratio for the LiteBIRD satellite. The code is available at: https://github.com/bthorne93/PySM_public.

  14. Predicting the sky from 30 MHz to 800 GHz: the extended Global Sky Model

    Science.gov (United States)

    Liu, Adrian

    We propose to construct the extended Global Sky Model (eGSM), a software package and associated data products that are capable of generating maps of the sky at any frequency within a broad range (30 MHz to 800 GHz). The eGSM is constructed from archival data, and its outputs will include not only "best estimate" sky maps, but also accurate error bars and the ability to generate random realizations of missing modes in the input data. Such views of the sky are crucial in the practice of precision cosmology, where our ability to constrain cosmological parameters and detect new phenomena (such as B-mode signatures from primordial gravitational waves, or spectral distortions of the Cosmic Microwave Background; CMB) rests crucially on our ability to remove systematic foreground contamination. Doing so requires empirical measurements of the foreground sky brightness (such as that arising from Galactic synchrotron radiation, among other sources), which are typically performed only at select narrow wavelength ranges. We aim to transcend traditional wavelength limits by optimally combining existing data to provide a comprehensive view of the foreground sky at any frequency within the broad range of 30 MHz to 800 GHz. Previous efforts to interpolate between multi-frequency maps resulted in the Global Sky Model (GSM) of de Oliveira-Costa et al. (2008), a software package that outputs foreground maps at any frequency of the user's choosing between 10 MHz and 100 GHz. However, the GSM has a number of shortcomings. First and foremost, the GSM does not include the latest archival data from the Planck satellite. Multi-frequency models depend crucially on data from Planck, WMAP, and COBE to provide high-frequency "anchor" maps. Another crucial shortcoming is the lack of error bars in the output maps. Finally, the GSM is only able to predict temperature (i.e., total intensity) maps, and not polarization information. With the recent release of Planck's polarized data products, the

  15. An extended cumulative logit model for detecting a shift in frequencies of sky-cloudiness conditions

    Science.gov (United States)

    Lu, Qiqi; Wang, Xiaolan L.

    2012-08-01

    In Canada, sky-cloudiness (or cloud cover) condition is reported in terms of tenths of the sky dome covered by clouds and hence has 11 categories (0/10 for clear sky, 1/10 for one tenth of the sky dome covered by clouds, …, and 10/10 for overcast). The cloud cover data often contain temporal discontinuities (changepoints) and present a large amount of observational uncertainty. Detecting changepoints in a sequence of continuous random variables has been extensively explored in both statistics and climatology literature. However, changepoint analyses of a multinomial sequence data with extra variabilities are relatively sparse. This study develops a likelihood ratio test for detecting a sudden change in parameters of the cumulative logit model for a multinomial sequence. The extra-multinomial variation is accounted for by allowing an overdispersion parameter in the model fitting. Moreover, the empirical distribution of the estimated changepoint is approximated by a bootstrap method. An application of this new technique to real sky cloudiness data in Canada is presented.

  16. Planck 2013 results. XI. All-sky model of thermal dust emission

    CERN Document Server

    Abergel, A; Aghanim, N; Alina, D; Alves, M I R; Armitage-Caplan, C; Arnaud, M; Ashdown, M; Atrio-Barandela, F; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartlett, J G; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bobin, J; Bock, J J; Bonaldi, A; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Bridges, M; Bucher, M; Burigana, C; Butler, R C; Cardoso, J -F; Catalano, A; Chamballu, A; Chary, R -R; Chiang, H C; Chiang, L -Y; Christensen, P R; Church, S; Clemens, M; Clements, D L; Colombi, S; Colombo, L P L; Combet, C; Couchot, F; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Delouis, J -M; Désert, F -X; Dickinson, C; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Dupac, X; Efstathiou, G; Enßlin, T A; Eriksen, H K; Falgarone, E; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Galeotta, S; Ganga, K; Ghosh, T; Giard, M; Giardino, G; Giraud-Héraud, Y; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Grenier, I A; Gruppuso, A; Guillet, V; Hansen, F K; Hanson, D; Harrison, D; Helou, G; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Hobson, M; Holmes, W A; Hornstrup, A; Hovest, W; Huffenberger, K M; Jaffe, A H; Jaffe, T R; Jewell, J; Joncas, G; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Knoche, J; Knox, L; Kunz, M; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J -M; Lasenby, A; Laureijs, R J; Lawrence, C R; Leonardi, R; León-Tavares, J; Lesgourgues, J; Levrier, F; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maffei, B; Maino, D; Mandolesi, N; Maris, M; Marshall, D J; Martin, P G; Martínez-González, E; Masi, S; Massardi, M; Matarrese, S; Matthai, F; Mazzotta, P; McGehee, P; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Osborne, S; Oxborrow, C A; Paci, F; Pagano, L; Pajot, F; Paladini, R; Paoletti, D; Pasian, F; Patanchon, G; Perdereau, O; Perotto, L; Perrotta, F; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Ponthieu, N; Popa, L; Poutanen, T; Pratt, G W; Prézeau, G; Prunet, S; Puget, J -L; Rachen, J P; Reach, W T; Rebolo, R; Reinecke, M; Remazeilles, M; Renault, C; Ricciardi, S; Riller, T; Ristorcelli, I; Rocha, G; Rosset, C; Roudier, G; Rowan-Robinson, M; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savini, G; Scott, D; Seiffert, M D; Shellard, E P S; Spencer, L D; Starck, J -L; Stolyarov, V; Stompor, R; Sudiwala, R; Sunyaev, R; Sureau, F; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Tavagnacco, D; Terenzi, L; Toffolatti, L; Tomasi, M; Tristram, M; Tucci, M; Tuovinen, J; Türler, M; Umana, G; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Vittorio, N; Wade, L A; Wandelt, B D; Welikala, N; Yvon, D; Zacchei, A; Zonca, A

    2014-01-01

    This paper presents an all-sky model of dust emission from the Planck 857, 545 and 353 GHz, and IRAS 100 micron data. Using a modified black-body fit to the data we present all-sky maps of the dust optical depth, temperature, and spectral index over the 353-3000 GHz range. This model is a tight representation of the data at 5 arcmin. It shows variations of the order of 30 % compared with the widely-used model of Finkbeiner, Davis, and Schlegel. The Planck data allow us to estimate the dust temperature uniformly over the whole sky, providing an improved estimate of the dust optical depth compared to previous all-sky dust model, especially in high-contrast molecular regions. An increase of the dust opacity at 353 GHz, tau_353/N_H, from the diffuse to the denser interstellar medium (ISM) is reported. It is associated with a decrease in the observed dust temperature, T_obs, that could be due at least in part to the increased dust opacity. We also report an excess of dust emission at HI column densities lower than...

  17. Sky view factor as a parameter in applied climatology rapid estimation by the SkyHelios model

    Directory of Open Access Journals (Sweden)

    Andreas Matzarakis

    2011-02-01

    Full Text Available Graphic processors can be integrated in simulation models computing e.g. three-dimensional flow visualization or radiation estimation. Going a step further it is even possible to use modern graphics hardware as general-purpose array processors. These ideas and approaches use a cheap mass production technology to solve specific problems. This technology can be applied for modelling climate conditions or climate-relevant parameters on the micro-scale or with respect to urban areas. To illustrate this we present the simulation of the continuous sky view factor (SVF, thus the calculation of the SVF for each point of a complex area. Digital elevation models (DEM, data concerning urban obstacles (OBS or other digital files can serve as a data base in order to quantify relevant climatic conditions in urban and complex areas. The following benefits are provided by the new model: (a short computing time (b short development time and (c low costs due to the use of open source frameworks. The application of the developed model will be helpful to estimate radiation fluxes and the mean radiant temperature in urban and complex situations accurately, especially in combination with an urban microclimate model, e.g. the RayMan model.

  18. A method for selecting the CIE standard general sky model with regard to calculating luminance distributions

    Science.gov (United States)

    Ferraro, Vittorio; Marinelli, Valerio; Mele, Marilena

    2013-04-01

    It is known that the best predictions of sky luminances are obtainable by the CIE 15 standard skies model, but the predictions by this model need knowledge of the measured luminance distributions themselves, since a criterion for selecting the type of sky starting from the irradiance values has not found until now. The authors propose a new simple method of applying the CIE model, based on the use of the sky index Si. A comparison between calculated luminance data and data measured in Arcavacata of Rende (Italy), Lyon (France) and Pamplona (Spain) show a good performance of this method in comparison with other methods of calculation of luminance existing in the literature.

  19. The Innsbruck/ESO sky models and telluric correction tools*

    Directory of Open Access Journals (Sweden)

    Kimeswenger S.

    2015-01-01

    While the ground based astronomical observatories just have to correct for the line-of-sight integral of these effects, the Čerenkov telescopes use the atmosphere as the primary detector. The measured radiation originates at lower altitudes and does not pass through the entire atmosphere. Thus, a decent knowledge of the profile of the atmosphere at any time is required. The latter cannot be achieved by photometric measurements of stellar sources. We show here the capabilities of our sky background model and data reduction tools for ground-based optical/infrared telescopes. Furthermore, we discuss the feasibility of monitoring the atmosphere above any observing site, and thus, the possible application of the method for Čerenkov telescopes.

  20. Modelling artificial night-sky brightness with a polarized multiple scattering radiative transfer computer code

    Science.gov (United States)

    Kerola, Dana Xavier

    2006-02-01

    As part of an ongoing investigation of radiative effects produced by hazy atmospheres, computational procedures have been developed for use in determining the brightening of the night sky as a result of urban illumination. The downwardly and upwardly directed radiances of multiply scattered light from an offending metropolitan source are computed by a straightforward Gauss-Seidel (G-S) iterative technique applied directly to the integrated form of Chandrasekhar's vectorized radiative transfer equation. Initial benchmark night-sky brightness tests of the present G-S model using fully consistent optical emission and extinction input parameters yield very encouraging results when compared with the double scattering treatment of Garstang, the only full-fledged previously available model.

  1. NOAA AVHRR Clear-Sky Products over Oceans (ACSPO): Sea Surface Temperature, Clear Sky Radiances, and Aerosol Optical Depth for the Global Ocean, 2011 - present (NCEI Accession 0072979)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The AVHRR Clear-Sky Processor over Oceans, jointly developed between NESDIS STAR and OSDPD, produces AVHRR clear-sky products over oceans. ACSPO generates output...

  2. Planck intermediate results. XXIX. All-sky dust modelling with Planck, IRAS, and WISE observations

    Science.gov (United States)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Alves, M. I. R.; Aniano, G.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartolo, N.; Battaner, E.; Benabed, K.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Couchot, F.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Dickinson, C.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Draine, B. T.; Ducout, A.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Falgarone, E.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Ghosh, T.; Giard, M.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gregorio, A.; Gruppuso, A.; Guillet, V.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Holmes, W. A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Levrier, F.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maffei, B.; Maino, D.; Mandolesi, N.; Maris, M.; Marshall, D. J.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; Mazzotta, P.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Natoli, P.; Nørgaard-Nielsen, H. U.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Pagano, L.; Pajot, F.; Paladini, R.; Paoletti, D.; Pasian, F.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Ponthieu, N.; Popa, L.; Pratt, G. W.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Ristorcelli, I.; Rocha, G.; Roudier, G.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Scott, D.; Spencer, L. D.; Stolyarov, V.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Umana, G.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; Ysard, N.; Yvon, D.; Zacchei, A.; Zonca, A.

    2016-02-01

    We present all-sky modelling of the high resolution Planck, IRAS, and WISE infrared (IR) observations using the physical dust model presented by Draine & Li in 2007 (DL, ApJ, 657, 810). We study the performance and results of this model, and discuss implications for future dust modelling. The present work extends the DL dust modelling carried out on nearby galaxies using Herschel and Spitzer data to Galactic dust emission. We employ the DL dust model to generate maps of the dust mass surface density ΣMd, the dust optical extinction AV, and the starlight intensity heating the bulk of the dust, parametrized by Umin. The DL model reproduces the observed spectral energy distribution (SED) satisfactorily over most of the sky, with small deviations in the inner Galactic disk and in low ecliptic latitude areas, presumably due to zodiacal light contamination. In the Andromeda galaxy (M31), the present dust mass estimates agree remarkably well (within 10%) with DL estimates based on independent Spitzer and Herschel data. We compare the DL optical extinction AV for the diffuse interstellar medium (ISM) with optical estimates for approximately 2 × 105 quasi-stellar objects (QSOs) observed inthe Sloan Digital Sky Survey (SDSS). The DL AV estimates are larger than those determined towards QSOs by a factor of about 2, which depends on Umin. The DL fitting parameter Umin, effectively determined by the wavelength where the SED peaks, appears to trace variations in the far-IR opacity of the dust grains per unit AV, and not only in the starlight intensity. These results show that some of the physical assumptions of the DL model will need to be revised. To circumvent the model deficiency, we propose an empirical renormalization of the DL AV estimate, dependent of Umin, which compensates for the systematic differences found with QSO observations. This renormalization, made to match the AV estimates towards QSOs, also brings into agreement the DL AV estimates with those derived for

  3. Satellite-Based All-Sky and Clear-Sky Direct Normal Irradiance: Application of a Global-to-Beam Model to the NASA GEWEX SRB Global Horizontal Irradiance and Validation against the BSRN Data

    Science.gov (United States)

    Zhang, T.; Stackhouse, P. W., Jr.; Westberg, D. J.

    2016-12-01

    The NASA GEWEX SRB Release 3.0 provides, among other things, surface downwelling solar irradiance, or global horizontal irradiance (GHI), on a global grid system of 1 degree latitude by 1 degree longitude. The dataset spans a 24.5-year period at 3-hourly temporal resolution from July 1983 to December 2007. The 3-hourly GHIs and daily and monthly means derived therefrom have been extensively validated against surface-based observations from the Baseline Surface Radiation Network (BSRN), the Pacific Marine Environmental Laboratory (PMEL), the World Radiation Data Centre (WRDC), and the Global Energy Balance Archive (GEBA). The DIRINDEX model is an empirical global-to-beam model which derives hourly direct normal irradiances (DNIs) from GHIs. We have applied this model to the GEWEX SRB Release 3.0 3-hourly GHIs and derived a set of DNIs at the same spatiotemporal resolution and time span. The model input includes both all-sky and clear-sky GHIs. Additional inputs include the Modern-Era Retrospective Analysis for Research and Applications (MERRA) atmospheric data and the Max-Planck Aerosol Climatology Version 1 (MAC-v1). The output DNIs are for both all-sky and clear-sky conditions as well. The all-sky 3-hourly, daily and monthly DNIs have been validated against their BSRN counterparts and good agreement has been achieved. The clear-sky DNIs were initially not in as good agreement with their BSRN counterparts. Based on the comparison statistics, we corrected the parameters of the DIRINDEX model relevant to the clear-sky DNIs and improved the output clear-sky DNIs. In this presentation, we show how the DNIs were derived and how they compare with the BSRN data. Intercomparison of the derived direct horizontal irradiance with that of the Clouds and the Earth's Radiant Energy System (CERES) will also be presented.

  4. GMOSS: All-sky Model of Spectral Radio Brightness Based on Physical Components and Associated Radiative Processes

    Science.gov (United States)

    Sathyanarayana Rao, Mayuri; Subrahmanyan, Ravi; Udaya Shankar, N.; Chluba, Jens

    2017-01-01

    We present the Global Model for the Radio Sky Spectrum (GMOSS), a novel, physically motivated model of the low-frequency radio sky from 22 MHz to 23 GHz. GMOSS invokes different physical components and associated radiative processes to describe the sky spectrum over 3072 pixels of 5° resolution. The spectra are allowed to be convex, concave, or of more complex form with contributions from synchrotron emission, thermal emission, and free-free absorption included. Physical parameters that describe the model are optimized to best fit four all-sky maps at 150 MHz, 408 MHz, 1420 MHz, and 23 GHz and two maps at 22 and 45 MHz generated using the Global Sky Model of de Oliveira-Costa et al. The fractional deviation of the model from data has a median value of 6% and is less than 17% for 99% of the pixels. Though aimed at the modeling of foregrounds for the global signal arising from the redshifted 21 cm line of hydrogen during the Cosmic Dawn and the Epoch of Reionization (EoR), over redshifts 150≲ z≲ 6, GMOSS is well suited for any application that requires simulating spectra of the low-frequency radio sky as would be observed by the beam of any instrument. The complexity in spectral structure that naturally arises from the underlying physics of the model provides a useful expectation for departures from smoothness in EoR foreground spectra and hence may guide the development of algorithms for EoR signal detection. This aspect is further explored in a subsequent paper.

  5. Measuring and modelling light pollution at the Zselic Starry Sky Park

    Energy Technology Data Exchange (ETDEWEB)

    Kollath, Zoltan, E-mail: kollath@konkoly.h [Konkoly Observatory, Konkoly Thege u. 15-17, H-1121 Budapest (Hungary)

    2010-03-01

    One of the first 'International Dark-sky Parks' in Europe was established at the Zselic Landscape Protection Area in Hungary. A special monitoring program has been carrying on to survey the quality of the night sky using 'Sky Quality Meters' and DSLR cameras. The main conclusion of our measurements is that the local villages have only a minimal effect on the quality of the sky. There are light-domes due to the neighbouring cities only close to the horizon, the main source of obtrusive light is the city of Kaposvar. The anthropogenic component of zenith luminance of the night sky is obtained as the function of the distance from the city centre of Kaposvar. Our data were modelled by radiation transfer calculations. These results can help to draw attention to the energy emitted useless to the space and to protect our nocturnal landscape of nature parks for the next generations.

  6. Measuring and modelling light pollution at the Zselic Starry Sky Park

    Science.gov (United States)

    Kolláth, Zoltán

    2010-03-01

    One of the first 'International Dark-sky Parks' in Europe was established at the Zselic Landscape Protection Area in Hungary. A special monitoring program has been carrying on to survey the quality of the night sky using 'Sky Quality Meters' and DSLR cameras. The main conclusion of our measurements is that the local villages have only a minimal effect on the quality of the sky. There are light-domes due to the neighbouring cities only close to the horizon, the main source of obtrusive light is the city of Kaposvár. The anthropogenic component of zenith luminance of the night sky is obtained as the function of the distance from the city centre of Kaposvár. Our data were modelled by radiation transfer calculations. These results can help to draw attention to the energy emitted useless to the space and to protect our nocturnal landscape of nature parks for the next generations.

  7. Design and Modelling of Water Chilling Production System by the Combined Effects of Evaporation and Night Sky Radiation

    Directory of Open Access Journals (Sweden)

    Ahmed Y. Taha Al-Zubaydi

    2014-01-01

    Full Text Available The design and mathematical modelling of thermal radiator panel to be used primarily to measure night sky radiation wet coated surface is presented in this paper. The panel consists of an upper dry surface coated aluminium sheet laminated to an ethylene vinyl acetate foam backing block as an insulation. Water is sprayed onto the surface of the panel so that an evaporative cooling effect is gained in addition to the radiation effect; the surface of a panel then is wetted in order to study and measure the night sky radiation from the panel wet surface. In this case, the measuring water is circulated over the upper face of this panel during night time. Initial TRNSYS simulations for the performance of the system are presented and it is planned to use the panel as calibrated instruments for discriminating between the cooling effects of night sky radiation and evaporation.

  8. A galaxy model from two micron all sky survey star counts in the whole sky, including the plane

    Energy Technology Data Exchange (ETDEWEB)

    Polido, P.; Jablonski, F. [Divisão de Astrofísica, Instituto Nacional de Pesquisas Espaciais, Avenida dos Astronautas 1758, 12227-010 São José dos Campos SP (Brazil); Lépine, J. R. D., E-mail: pripolido@gmail.com [Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, Rua do Matão 1226, 05508-900 São Paulo SP (Brazil)

    2013-11-20

    We use the star count model of Ortiz and Lépine to perform an unprecedented exploration of the most important Galactic parameters comparing the predicted counts with the Two Micron All Sky Survey observed star counts in the J, H, and K{sub S} bands for a grid of positions covering the whole sky. The comparison is made using a grid of lines of sight given by the HEALPix pixelization scheme. The resulting best-fit values for the parameters are: 2120 ± 200 pc for the radial scale length and 205 ± 40 pc for the scale height of the thin disk, with a central hole of 2070{sub −800}{sup +2000} pc for the same disk, 3050 ± 500 pc for the radial scale length and 640 ± 70 pc for the scale height of the thick disk, 400 ± 100 pc for the central dimension of the spheroid, 0.0082 ± 0.0030 for the spheroid to disk density ratio, and 0.57 ± 0.05 for the oblate spheroid parameter.

  9. RESRAD model presentation

    Energy Technology Data Exchange (ETDEWEB)

    Yu, C.; Faillace, E.; Chen, S.Y. [Argonne National Lab., IL (United States); Wallo, A. III; Williams, W.A.; Peterson, H.; Domotor, S. [Dept. of Energy, Washington, DC (United States)

    1998-05-01

    RESRAD was one of the multimedia models selected by the US Nuclear Regulatory Commission (NRC) to include in its workshop on radiation dose modeling and demonstration of compliance with the radiological criteria for license termination. This paper is a summary of the presentation made at the workshop and focuses on the 10 questions the NRC distributed to all participants prior to the workshop. The code selection criteria, which were solicited by the NRC, for demonstrating compliance with the license termination rule are also included. Among the RESRAD family of codes, RESRAD and RESRAD-BUILD are designed for evaluating radiological contamination in soils and in buildings. Many documents have been published to support the use of these codes. This paper focuses on these two codes. The pathways considered, the databases and parameters used, quality control and quality assurance, benchmarking, verification and validation of these codes, and capabilities as well as limitations of these codes are discussed in detail.

  10. Towards closure between measured and modelled UV under clear skies at four diverse sites

    Directory of Open Access Journals (Sweden)

    J. Badosa

    2007-06-01

    Full Text Available The purpose of this work is determine the extent of closure between measurements and models of UV irradiances at diverse sites using state of the art instruments, models, and the best available data as inputs to the models. These include information about aerosol optical depth (unfortunately not extending down as far into the UVB region as desirable because such information is not generally available, ozone column amounts, as well as vertical profiles of temperature. We concentrate on clear-sky irradiances, and report the results in terms of UV Index (UVI.

    Clear-sky data from one year of measurements at each of four diverse sites (Lauder – New Zealand, Mauna Loa Observatory – Hawaii, Boulder – Colorado, and Melbourne – Australia have been analysed in detail, also taking account of different measurements of ozone, including satellite-derived values, as well as ground measured values, both from Dobson instruments and as retrieved from the UV spectra under study. Previous studies have generally focussed on data from a single site, and for shorter periods. As such, it is the most comprehensive study of its kind to date.

    At Lauder, which is the cleanest low altitude site, we obtained agreement between measurement and model at 5% level, which is consistent with the best agreement found previously. At Mauna Loa Observatory, similar agreement was achieved, but model calculations need to allow for reflections from cloud that are present below the observatory. At this site, there are occasional problems with using satellite-derived ozone. At Boulder, mean agreements were similar but the dispersion around the mean was slightly larger, corresponding to larger uncertainties in the aerosol inputs to the model. However, at Melbourne, which is the only non-NDACC (Network for the Detection of Atmospheric Composition Change site, there remain unexplained discrepancies. The measured values are significantly lower than the calculated

  11. What does it mean to manage sky survey data? A model to facilitate stakeholder conversations

    Science.gov (United States)

    Sands, Ashley E.; Darch, Peter T.

    2016-06-01

    Astronomy sky surveys, while of great scientific value independently, can be deployed even more effectively when multiple sources of data are combined. Integrating discrete datasets is a non-trivial exercise despite investments in standard data formats and tools. Creating and maintaining data and associated infrastructures requires investments in technology and expertise. Combining data from multiple sources necessitates a common understanding of data, structures, and goals amongst relevant stakeholders.We present a model of Astronomy Stakeholder Perspectives on Data. The model is based on 80 semi-structured interviews with astronomers, computational astronomers, computer scientists, and others involved in the building or use of the Sloan Digital Sky Survey (SDSS) and Large Synoptic Survey Telescope (LSST). Interviewees were selected to ensure a range of roles, institutional affiliations, career stages, and level of astronomy education. Interviewee explanations of data were analyzed to understand how perspectives on astronomy data varied by stakeholder.Interviewees described sky survey data either intrinsically or extrinsically. “Intrinsic” descriptions of data refer to data as an object in and of itself. Respondents with intrinsic perspectives view data management in one of three ways: (1) “Medium” - securing the zeros and ones from bit rot; (2) “Scale” - assuring that changes in state are documented; or (3) “Content” - ensuring the scientific validity of the images, spectra, and catalogs.“Extrinsic” definitions, in contrast, define data in relation to other forms of information. Respondents with extrinsic perspectives view data management in one of three ways: (1) “Source” - supporting the integrity of the instruments and documentation; (2) “Relationship” - retaining relationships between data and their analytical byproducts; or (3) “Use” - ensuring that data remain scientifically usable.This model shows how data management can

  12. Modelling UV irradiances on arbitrarily oriented surfaces: effects of sky obstructions

    Directory of Open Access Journals (Sweden)

    M. Hess

    2008-07-01

    Full Text Available A method is presented to calculate UV irradiances on inclined surfaces that additionally takes into account the influence of sky obstructions caused by obstacles such as mountains, houses, trees, or umbrellas. With this method it is thus possible to calculate the impact of UV radiation on biological systems, such as, for instance, the human skin or eye, in any natural or artificial environment. The method, which consists of a combination of radiation models, is explained here and the accuracy of its results is demonstrated. The effect of a natural skyline is shown for an Alpine ski area, where the UV irradiance even on a horizontal surface may increase due to reflection from snow by more than 10 percent. In contrast, in a street canyon the irradiance on a horizontal surface is reduced to 30% in shadow and to about 75% for a position in the sun.

  13. Modelling UV irradiances on arbitrarily oriented surfaces: effects of sky obstructions

    Science.gov (United States)

    Hess, M.; Koepke, P.

    2008-07-01

    A method is presented to calculate UV irradiances on inclined surfaces that additionally takes into account the influence of sky obstructions caused by obstacles such as mountains, houses, trees, or umbrellas. With this method it is thus possible to calculate the impact of UV radiation on biological systems, such as, for instance, the human skin or eye, in any natural or artificial environment. The method, which consists of a combination of radiation models, is explained here and the accuracy of its results is demonstrated. The effect of a natural skyline is shown for an Alpine ski area, where the UV irradiance even on a horizontal surface may increase due to reflection from snow by more than 10 percent. In contrast, in a street canyon the irradiance on a horizontal surface is reduced to 30% in shadow and to about 75% for a position in the sun.

  14. Foreground removal from Planck Sky Model temperature maps using a MLP neural network

    DEFF Research Database (Denmark)

    Nørgaard-Nielsen, Hans Ulrik; Hebert, K.

    2009-01-01

    with no systematic errors. To demonstrate the feasibility of a simple multilayer perceptron (MLP) neural network for extracting the CMB temperature signal, we have analyzed a specific data set, namely the Planck Sky Model maps, developed for evaluation of different component separation methods before including them...... in the Planck data analysis pipeline. It is found that a MLP neural network can provide a CMB map of about 80% of the sky to a very high degree uncorrelated with the foreground components. Also the derived power spectrum shows little evidence for systematic errors....

  15. Photon path length distributions for cloudy skies – oxygen A-Band measurements and model calculations

    Directory of Open Access Journals (Sweden)

    O. Funk

    2003-03-01

    Full Text Available This paper addresses the statistics underlying cloudy sky radiative transfer (RT by inspection of the distribution of the path lengths of solar photons. Recent studies indicate that this approach is promising, since it might reveal characteristics about the diffusion process underlying atmospheric radiative transfer (Pfeilsticker, 1999. Moreover, it uses an observable that is directly related to the atmospheric absorption and, therefore, of climatic relevance. However, these studies are based largely on the accuracy of the measurement of the photon path length distribution (PPD. This paper presents a refined analysis method based on high resolution spectroscopy of the oxygen A-band. The method is validated by Monte Carlo simulation atmospheric spectra. Additionally, a new method to measure the effective optical thickness of cloud layers, based on fitting the measured differential transmissions with a 1-dimensional (discrete ordinate RT model, is presented. These methods are applied to measurements conducted during the cloud radar inter-comparison campaign CLARE’98, which supplied detailed cloud structure information, required for the further analysis. For some exemplary cases, measured path length distributions and optical thicknesses are presented and backed by detailed RT model calculations. For all cases, reasonable PPDs can be retrieved and the effects of the vertical cloud structure are found. The inferred cloud optical thicknesses are in agreement with liquid water path measurements. Key words. Meteorology and atmospheric dynamics (radiative processes; instruments and techniques

  16. Photon path length distributions for cloudy skies – oxygen A-Band measurements and model calculations

    Directory of Open Access Journals (Sweden)

    O. Funk

    Full Text Available This paper addresses the statistics underlying cloudy sky radiative transfer (RT by inspection of the distribution of the path lengths of solar photons. Recent studies indicate that this approach is promising, since it might reveal characteristics about the diffusion process underlying atmospheric radiative transfer (Pfeilsticker, 1999. Moreover, it uses an observable that is directly related to the atmospheric absorption and, therefore, of climatic relevance. However, these studies are based largely on the accuracy of the measurement of the photon path length distribution (PPD. This paper presents a refined analysis method based on high resolution spectroscopy of the oxygen A-band. The method is validated by Monte Carlo simulation atmospheric spectra. Additionally, a new method to measure the effective optical thickness of cloud layers, based on fitting the measured differential transmissions with a 1-dimensional (discrete ordinate RT model, is presented. These methods are applied to measurements conducted during the cloud radar inter-comparison campaign CLARE’98, which supplied detailed cloud structure information, required for the further analysis. For some exemplary cases, measured path length distributions and optical thicknesses are presented and backed by detailed RT model calculations. For all cases, reasonable PPDs can be retrieved and the effects of the vertical cloud structure are found. The inferred cloud optical thicknesses are in agreement with liquid water path measurements.

    Key words. Meteorology and atmospheric dynamics (radiative processes; instruments and techniques

  17. The red sky enigma over Svalbard in December 2002: a model using polar stratospheric clouds

    Directory of Open Access Journals (Sweden)

    N. D. Lloyd

    2005-07-01

    Full Text Available An anomalous red glow due to scattered sunlight was observed at Longyearbyen (78° N, 15° E on 6 December 2002 from 07:30 UT to 13:30 UT when the solar zenith angle varied between 100.7° and 104°. A model for this red sky event using sunlight scattered in a two stage process by Polar Stratospheric Clouds (PSC at 25km is presented and demonstrated to be feasible. The model requires a significant fraction of the polar vortex, which is cold enough for the formation of ice PSC, to be occupied with PSC with an integrated vertical extinction of approximately 0.037 at 845nm. Given these conditions, the model is able to predict, within an order of magnitude, the spatial distribution of intensities measured by meridional scanning photometers located at Longyearbyen across the visible and near infra-red spectrum. Keywords. Aerosols and particles; Transmission and scattering of radiation; Polar Meteorology

  18. X-band COSMO-SkyMed wind field retrieval, with application to coastal circulation modeling

    Directory of Open Access Journals (Sweden)

    A. Montuori

    2013-02-01

    Full Text Available In this paper, X-band COSMO-SkyMed© synthetic aperture radar (SAR wind field retrieval is investigated, and the obtained data are used to force a coastal ocean circulation model. The SAR data set consists of 60 X-band Level 1B Multi-Look Ground Detected ScanSAR Huge Region COSMO-SkyMed© SAR data, gathered in the southern Tyrrhenian Sea during the summer and winter seasons of 2010. The SAR-based wind vector field estimation is accomplished by resolving both the SAR-based wind speed and wind direction retrieval problems independently. The sea surface wind speed is retrieved by means of a SAR wind speed algorithm based on the azimuth cut-off procedure, while the sea surface wind direction is provided by means of a SAR wind direction algorithm based on the discrete wavelet transform multi-resolution analysis. The obtained wind fields are compared with ground truth data provided by both ASCAT scatterometer and ECMWF model wind fields. SAR-derived wind vector fields and ECMWF model wind data are used to construct a blended wind product regularly sampled in both space and time, which is then used to force a coastal circulation model of a southern Tyrrhenian coastal area to simulate wind-driven circulation processes. The modeling results show that X-band COSMO-SkyMed© SAR data can be valuable in providing effective wind fields for coastal circulation modeling.

  19. Integrating hydrodynamic models and COSMO-SkyMed derived products for flood damage assessment

    Science.gov (United States)

    Giuffra, Flavio; Boni, Giorgio; Pulvirenti, Luca; Pierdicca, Nazzareno; Rudari, Roberto; Fiorini, Mattia

    2015-04-01

    Floods are the most frequent weather disasters in the world and probably the most costly in terms of social and economic losses. They may have a strong impact on infrastructures and health because the range of possible damages includes casualties, loss of housing and destruction of crops. Presently, the most common approach for remotely sensing floods is the use of synthetic aperture radar (SAR) images. Key features of SAR data for inundation mapping are the synoptic view, the capability to operate even in cloudy conditions and during both day and night time and the sensitivity of the microwave radiation to water. The launch of a new generation of instruments, such as TerraSAR-X and COSMO-SkyMed (CSK) allows producing near real time flood maps having a spatial resolution in the order of 1-5 m. Moreover, the present (CSK) and upcoming (Sentinel-1) constellations permit the acquisition of radar data characterized by a short revisit time (in the order of some hours for CSK), so that the production of frequent inundation maps can be envisaged. Nonetheless, gaps might be present in the SAR-derived flood maps because of the limited area imaged by SAR; moreover, the detection of floodwater may be complicated by the presence of very dense vegetation or urban settlements. Hence the need to complement SAR-derived flood maps with the outputs of physical models. Physical models allow delivering to end users very useful information for a complete flood damage assessment, such as data on water depths and flow directions, which cannot be directly derived from satellite remote sensing images. In addition, the flood extent predictions of hydraulic models can be compared to SAR-derived inundation maps to calibrate the models, or to fill the aforementioned gaps that can be present in the SAR-derived maps. Finally, physical models enable the construction of risk scenarios useful for emergency managers to take their decisions and for programming additional SAR acquisitions in order to

  20. Sky-Hook Control and Kalman Filtering in Nonlinear Model of Tracked Vehicle Suspension System

    Directory of Open Access Journals (Sweden)

    Jurkiewicz Andrzej

    2017-09-01

    Full Text Available The essence of the undertaken topic is application of the continuous sky-hook control strategy and the Extended Kalman Filter as the state observer in the 2S1 tracked vehicle suspension system. The half-car model of this suspension system consists of seven logarithmic spiral springs and two magnetorheological dampers which has been described by the Bingham model. The applied continuous sky-hook control strategy considers nonlinear stiffness characteristic of the logarithmic spiral springs. The control is determined on estimates generated by the Extended Kalman Filter. Improve of ride comfort is verified by comparing simulation results, under the same driving conditions, of controlled and passive vehicle suspension systems.

  1. Sky Fest: A Model of Successful Scientist Participation in E/PO

    Science.gov (United States)

    Dalton, H.; Shipp, S. S.; Shaner, A. J.; LaConte, K.; Shupla, C. B.

    2014-12-01

    Participation in outreach events is an easy way for scientists to get involved with E/PO and reach many people with minimal time commitment. At the Lunar and Planetary Institute (LPI) in Houston, Texas, the E/PO team holds Sky Fest outreach events several times a year. These events each have a science content theme and include several activities for children and their parents, night sky viewing through telescopes, and scientist presentations. LPI scientists have the opportunity to participate in Sky Fest events either by helping lead an activity or by giving the scientist presentation (a short lecture and/or demonstration). Scientists are involved in at least one preparation meeting before the event. This allows them to ask questions, understand what activity they will be leading, and learn the key points that they should be sharing with the public, as well as techniques for effectively teaching members of the public about the event topic. During the event, each activity is run by one E/PO specialist and one scientist, enabling the scientist to learn about effective E/PO practices from the E/PO specialist and the E/PO specialist to get more science information about the event topic. E/PO specialists working together with scientists at stations provides a more complete, richer experience for event participants. Surveys of event participants have shown that interacting one-on-one with scientists is often one of their favorite parts of the events. Interviews with scientists indicated that they enjoyed Sky Fest because there was very little time involved on their parts outside of the actual event; the activities were created and/or chosen by the E/PO professionals, and setup for the events was completed before they arrived. They also enjoyed presenting their topic to people without a background in science, and who would not have otherwise sought out the information that was presented.

  2. SkyFACT: high-dimensional modeling of gamma-ray emission with adaptive templates and penalized likelihoods

    Science.gov (United States)

    Storm, Emma; Weniger, Christoph; Calore, Francesca

    2017-08-01

    We present SkyFACT (Sky Factorization with Adaptive Constrained Templates), a new approach for studying, modeling and decomposing diffuse gamma-ray emission. Like most previous analyses, the approach relies on predictions from cosmic-ray propagation codes like GALPROP and DRAGON. However, in contrast to previous approaches, we account for the fact that models are not perfect and allow for a very large number (gtrsim 105) of nuisance parameters to parameterize these imperfections. We combine methods of image reconstruction and adaptive spatio-spectral template regression in one coherent hybrid approach. To this end, we use penalized Poisson likelihood regression, with regularization functions that are motivated by the maximum entropy method. We introduce methods to efficiently handle the high dimensionality of the convex optimization problem as well as the associated semi-sparse covariance matrix, using the L-BFGS-B algorithm and Cholesky factorization. We test the method both on synthetic data as well as on gamma-ray emission from the inner Galaxy, |l|<90o and |b|<20o, as observed by the Fermi Large Area Telescope. We finally define a simple reference model that removes most of the residual emission from the inner Galaxy, based on conventional diffuse emission components as well as components for the Fermi bubbles, the Fermi Galactic center excess, and extended sources along the Galactic disk. Variants of this reference model can serve as basis for future studies of diffuse emission in and outside the Galactic disk.

  3. Using two light-pollution models to investigate artificial sky radiances at Canary Islands observatories

    Science.gov (United States)

    Aubé, M.; Kocifaj, M.

    2012-05-01

    Astronomical observations are increasingly limited by light pollution, which is a product of the over-illumination of the night sky. To predict both the angular distribution of scattered light and the ground-reaching radiative fluxes, a set of models has been introduced in recent decades. Two distinct numerical tools, MSNsRAu and ILLUMINA, are compared in this paper, with the aim of identifying their strengths and weaknesses. The numerical experiment comprises the simulation of spectral radiances in the region of the Canary Islands. In particular, the light fields near the Roque de los Muchachos and Teide observatories are computed under various turbidity conditions. It is shown that ILLUMINA has enhanced accuracy at low elevation angles. However, ILLUMINA is time-consuming because of the two scattering orders incorporated into the calculation scheme. Under low-turbidity conditions and for zenith angles smaller than 70° the two models agree well, and thus can be successfully applied to typical cloudless situations at the majority of observatories. MSNsRAu is well optimized for large-scale simulations. In particular, the grid size is adapted dynamically depending on the distance between a light source and a hypothetical observer. This enables rapid numerical modelling for large territories. MSNsRAu is also well suited for the mass modelling of night-sky radiances after ground-based light sources are hypothetically changed. This enables an optimum design of public lighting systems and a time-efficient evaluation of the optical effects related to different lamp spectra or different lamp distributions. ILLUMINA provides two diagnostic geographical maps to help local authorities concerned about light-pollution control. The first map allows the identification of the relative contribution of each ground element to the observed sky radiance at a given viewing angle, while the second map gives the sensitivity, basically saying how each ground element contributes per lumen

  4. Paradoxes of nautical charts (model) of the sky for further space travel

    OpenAIRE

    Mykola, Lytvynchuk

    2015-01-01

    The man penetrates deeper into the mysteries of matter, space and time in the evolutionary development. He has only started the practical development of near space, but he already begins to travel into its depth in his dreams. One of the attributes of long-duration space travel is navigation charts (models) of the Universe considering an exact arrangement of cosmic bodies and their gravitational fields in space. For drawing up of such charts of the starry sky from the Earth it is necessary to...

  5. Testing the Two-Layer Model for Correcting Clear Sky Reflectance near Clouds

    Science.gov (United States)

    Wen, Guoyong; Marshak, Alexander; Evans, Frank; Varnai, Tamas; Levy, Rob

    2015-01-01

    A two-layer model (2LM) was developed in our earlier studies to estimate the clear sky reflectance enhancement due to cloud-molecular radiative interaction at MODIS at 0.47 micrometers. Recently, we extended the model to include cloud-surface and cloud-aerosol radiative interactions. We use the LES/SHDOM simulated 3D true radiation fields to test the 2LM for reflectance enhancement at 0.47 micrometers. We find: The simple model captures the viewing angle dependence of the reflectance enhancement near cloud, suggesting the physics of this model is correct; the cloud-molecular interaction alone accounts for 70 percent of the enhancement; the cloud-surface interaction accounts for 16 percent of the enhancement; the cloud-aerosol interaction accounts for an additional 13 percent of the enhancement. We conclude that the 2LM is simple to apply and unbiased.

  6. ESA Sky

    Science.gov (United States)

    Merin, Bruno

    2015-12-01

    The ESAC Science Data Centre, ESDC, is working on a science-driven discovery portal for all its astronomy missions with the provisional name Multi-Mission Interface. The first public release of this service will be demonstrated, featuring an interface for sky exploration and for single and multiple target searches. It requires no prior knowledge of any of the missions involved. From a technical point of view, the system offers all-sky projections of full mission datasets using a new-generation HEALPix projection called HiPS; detailed geometrical footprints to access individual observations at the mission archives using VO-TAP queries; and direct access to the underlying mission-specific science archives. A first public release is scheduled before the end of 2015 and will give users worldwide simplified access to high-level science-ready data products from all ESA Astronomy missions plus a number of ESA-produced source catalogues. A demo will accompany the presentation.

  7. From the Scale Model of the Sky to the Armillary Sphere

    CERN Document Server

    Gangui, Alejandro; Paez, Carlos

    2015-01-01

    It is customary to employ a semi-spherical scale model to describe the apparent path of the Sun across the sky, whether it be its diurnal motion or its variation throughout the year. A flat surface and three bent semi-rigid wires (representing the three solar arcs during solstices and equinoxes) will do the job. On the other hand, since very early times, there have been famous armillary spheres built and employed by the most outstanding astronomers for the description of the celestial movements. In those instruments, many of them now considered true works of art, Earth lies in the center of the cosmos and the observer looks at the whole "from the outside." Of course, both devices, the scale model of the sky and the armillary sphere, serve to represent the movement of the Sun, and in this paper we propose to show their equivalence by a simple construction. Knowing the basics underlying the operation of the armillary sphere will give us confidence to use it as a teaching resource in school.

  8. Modeling Ships and Space Craft The Science and Art of Mastering the Oceans and Sky

    CERN Document Server

    Hagler, Gina

    2013-01-01

    Modeling Ships and Space Craft: The Science and Art of Mastering the Oceans and Sky begins with the theories of Aristotle and Archimedes, moving on to examine the work of Froude and Taylor, the early aviators and the Wright Brothers, Goddard and the other rocket men, and the computational fluid dynamic models of our time. It examines the ways each used fluid dynamic principles in the design of their vessels. In the process, this book covers the history of hydrodynamic (aero and fluid) theory and its progression – with some very accessible science examples – including seminal theories. Hydrodynamic principles in action are also explored with examples from nature and the works of man. This is a book for anyone interested in the history of technology – specifically the methods and science behind the use of scale models and hydrodynamic principles in the marine and aeronautical designs of today.

  9. First-Year Sloan Digital Sky Survey-II (SDSS-II) Supernova Results: Constraints on Nonstandard Cosmological Models

    Science.gov (United States)

    Sollerman, J.; Mörtsell, E.; Davis, T. M.; Blomqvist, M.; Bassett, B.; Becker, A. C.; Cinabro, D.; Filippenko, A. V.; Foley, R. J.; Frieman, J.; Garnavich, P.; Lampeitl, H.; Marriner, J.; Miquel, R.; Nichol, R. C.; Richmond, M. W.; Sako, M.; Schneider, D. P.; Smith, M.; Vanderplas, J. T.; Wheeler, J. C.

    2009-10-01

    We use the new Type Ia supernovae discovered by the Sloan Digital Sky Survey-II supernova survey, together with additional supernova data sets as well as observations of the cosmic microwave background and baryon acoustic oscillations to constrain cosmological models. This complements the standard cosmology analysis presented by Kessler et al. in that we discuss and rank a number of the most popular nonstandard cosmology scenarios. When this combined data set is analyzed using the MLCS2k2 light-curve fitter, we find that more exotic models for cosmic acceleration provide a better fit to the data than the ΛCDM model. For example, the flat Dvali-Gabadadze-Porrati model is ranked higher by our information-criteria (IC) tests than the standard model with a flat universe and a cosmological constant. When the supernova data set is instead analyzed using the SALT-II light-curve fitter, the standard cosmological-constant model fares best. This investigation of how sensitive cosmological model selection is to assumptions about, and within, the light-curve fitters thereby highlights the need for an improved understanding of these unresolved systematic effects. Our investigation also includes inhomogeneous Lemaître-Tolman-Bondi (LTB) models. While our LTB models can be made to fit the supernova data as well as any other model, the extra parameters they require are not supported by our IC analysis. Finally, we explore more model-independent ways to investigate the cosmic expansion based on this new data set.

  10. Validation of the Two-Layer Model for Correcting Clear Sky Reflectance Near Clouds

    Science.gov (United States)

    Wen, Guoyong; Marshak, Alexander; Evans, K. Frank; Vamal, Tamas

    2014-01-01

    A two-layer model was developed in our earlier studies to estimate the clear sky reflectance enhancement near clouds. This simple model accounts for the radiative interaction between boundary layer clouds and molecular layer above, the major contribution to the reflectance enhancement near clouds for short wavelengths. We use LES/SHDOM simulated 3D radiation fields to valid the two-layer model for reflectance enhancement at 0.47 micrometer. We find: (a) The simple model captures the viewing angle dependence of the reflectance enhancement near cloud, suggesting the physics of this model is correct; and (b) The magnitude of the 2-layer modeled enhancement agree reasonably well with the "truth" with some expected underestimation. We further extend our model to include cloud-surface interaction using the Poisson model for broken clouds. We found that including cloud-surface interaction improves the correction, though it can introduced some over corrections for large cloud albedo, large cloud optical depth, large cloud fraction, large cloud aspect ratio. This over correction can be reduced by excluding scenes (10 km x 10km) with large cloud fraction for which the Poisson model is not designed for. Further research is underway to account for the contribution of cloud-aerosol radiative interaction to the enhancement.

  11. A-Train Aerosol Observations Preliminary Comparisons with AeroCom Models and Pathways to Observationally Based All-Sky Estimates

    Science.gov (United States)

    Redemann, J.; Livingston, J.; Shinozuka, Y.; Kacenelenbogen, M.; Russell, P.; LeBlanc, S.; Vaughan, M.; Ferrare, R.; Hostetler, C.; Rogers, R.; hide

    2014-01-01

    We have developed a technique for combining CALIOP aerosol backscatter, MODIS spectral AOD (aerosol optical depth), and OMI AAOD (absorption aerosol optical depth) retrievals for the purpose of estimating full spectral sets of aerosol radiative properties, and ultimately for calculating the 3-D distribution of direct aerosol radiative forcing. We present results using one year of data collected in 2007 and show comparisons of the aerosol radiative property estimates to collocated AERONET retrievals. Use of the recently released MODIS Collection 6 data for aerosol optical depths derived with the dark target and deep blue algorithms has extended the coverage of the multi-sensor estimates towards higher latitudes. We compare the spatio-temporal distribution of our multi-sensor aerosol retrievals and calculations of seasonal clear-sky aerosol radiative forcing based on the aerosol retrievals to values derived from four models that participated in the latest AeroCom model intercomparison initiative. We find significant inter-model differences, in particular for the aerosol single scattering albedo, which can be evaluated using the multi-sensor A-Train retrievals. We discuss the major challenges that exist in extending our clear-sky results to all-sky conditions. On the basis of comparisons to suborbital measurements, we present some of the limitations of the MODIS and CALIOP retrievals in the presence of adjacent or underlying clouds. Strategies for meeting these challenges are discussed.

  12. Genus Topology of Structure in the Sloan Digital Sky Survey: Model Testing

    Science.gov (United States)

    Gott, J. Richard, III; Hambrick, D. Clay; Vogeley, Michael S.; Kim, Juhan; Park, Changbom; Choi, Yun-Young; Cen, Renyue; Ostriker, Jeremiah P.; Nagamine, Kentaro

    2008-03-01

    We measure the three-dimensional topology of large-scale structure in the Sloan Digital Sky Survey (SDSS). This allows the genus statistic to be measured with unprecedented statistical accuracy. The sample size is now sufficiently large to allow the topology to be an important tool for testing galaxy formation models. For comparison, we make mock SDSS samples using several state-of-the-art N-body simulations: the Millennium run of Springel et al. (10 billion particles), the Kim & Park CDM models (1.1 billion particles), and the Cen & Ostriker hydrodynamic code models (8.6 billion cell hydro mesh). Each of these simulations uses a different method for modeling galaxy formation. The SDSS data show a genus curve that is broadly characteristic of that produced by Gaussian random-phase initial conditions. Thus, the data strongly support the standard model of inflation where Gaussian random-phase initial conditions are produced by random quantum fluctuations in the early universe. But on top of this general shape there are measurable differences produced by nonlinear gravitational effects and biasing connected with galaxy formation. The N-body simulations have been tuned to reproduce the power spectrum and multiplicity function but not topology, so topology is an acid test for these models. The data show a "meatball" shift (only partly due to the Sloan Great Wall of galaxies) that differs at the 2.5 σ level from the results of the Millenium run and the Kim & Park dark halo models, even including the effects of cosmic variance.

  13. Comparison of Microclimate Simulated weather data to ASHRAE Clear Sky Model and Measured Data

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Mahabir S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-06-01

    In anticipation of emerging global urbanization and its impact on microclimate, a need exists to better understand and quantify microclimate effects on building energy use. Satisfaction of this need will require coordinated research of microclimate impacts on and from “human systems.” The Urban Microclimate and Energy Tool (Urban-MET) project seeks to address this need by quantifying and analyzing the relationships among climatic conditions, urban morphology, land cover, and energy use; and using these relationships to inform energy-efficient urban development and planning. Initial research will focus on analysis of measured and modeled energy efficiency of various building types in selected urban areas and temporal variations in energy use for different urban morphologies under different microclimatic conditions. In this report, we analyze the differences between microclimate weather data sets for the Oak Ridge National Laboratory campus produced by ENVI-met and Weather Research Forecast (WRF) models, the ASHRAE clear sky which defines the maximum amounts of solar radiation that can be expected, and measured data from a weather station on campus. Errors with climate variables and their impact on building energy consumption will be shown for the microclimate simulations to help prioritize future improvement for use in microclimate simulation impacts to energy use of buildings.

  14. From Near-Neutral to Strongly Stratified: Adequately Modelling the Clear-Sky Nocturnal Boundary Layer at Cabauw

    Science.gov (United States)

    Baas, P.; van de Wiel, B. J. H.; van der Linden, S. J. A.; Bosveld, F. C.

    2017-10-01

    The performance of an atmospheric single-column model (SCM) is studied systematically for stably-stratified conditions. To this end, 11 years (2005-2015) of daily SCM simulations were compared to observations from the Cabauw observatory, The Netherlands. Each individual clear-sky night was classified in terms of the ambient geostrophic wind speed with a 1 m s^{-1} bin-width. Nights with overcast conditions were filtered out by selecting only those nights with an average net radiation of less than - 30 W m^{-2} . A similar procedure was applied to the observational dataset. A comparison of observed and modelled ensemble-averaged profiles of wind speed and potential temperature and time series of turbulent fluxes showed that the model represents the dynamics of the nocturnal boundary layer (NBL) at Cabauw very well for a broad range of mechanical forcing conditions. No obvious difference in model performance was found between near-neutral and strongly-stratified conditions. Furthermore, observed NBL regime transitions are represented in a natural way. The reference model version performs much better than a model version that applies excessive vertical mixing as is done in several (global) operational models. Model sensitivity runs showed that for weak-wind conditions the inversion strength depends much more on details of the land-atmosphere coupling than on the turbulent mixing. The presented results indicate that in principle the physical parametrizations of large-scale atmospheric models are sufficiently equipped for modelling stably-stratified conditions for a wide range of forcing conditions.

  15. From Near-Neutral to Strongly Stratified: Adequately Modelling the Clear-Sky Nocturnal Boundary Layer at Cabauw

    Science.gov (United States)

    Baas, P.; van de Wiel, B. J. H.; van der Linden, S. J. A.; Bosveld, F. C.

    2018-02-01

    The performance of an atmospheric single-column model (SCM) is studied systematically for stably-stratified conditions. To this end, 11 years (2005-2015) of daily SCM simulations were compared to observations from the Cabauw observatory, The Netherlands. Each individual clear-sky night was classified in terms of the ambient geostrophic wind speed with a 1 m s^{-1} bin-width. Nights with overcast conditions were filtered out by selecting only those nights with an average net radiation of less than - 30 W m^{-2}. A similar procedure was applied to the observational dataset. A comparison of observed and modelled ensemble-averaged profiles of wind speed and potential temperature and time series of turbulent fluxes showed that the model represents the dynamics of the nocturnal boundary layer (NBL) at Cabauw very well for a broad range of mechanical forcing conditions. No obvious difference in model performance was found between near-neutral and strongly-stratified conditions. Furthermore, observed NBL regime transitions are represented in a natural way. The reference model version performs much better than a model version that applies excessive vertical mixing as is done in several (global) operational models. Model sensitivity runs showed that for weak-wind conditions the inversion strength depends much more on details of the land-atmosphere coupling than on the turbulent mixing. The presented results indicate that in principle the physical parametrizations of large-scale atmospheric models are sufficiently equipped for modelling stably-stratified conditions for a wide range of forcing conditions.

  16. Openness to Experience and Night-Sky Watching Interest as Predictors of Reading for Pleasure: Path Analysis of a Mediation Model

    Science.gov (United States)

    Kelly, William E.

    2010-01-01

    The relation between reading for pleasure, night-sky watching interest, and openness to experience were examined in a sample of 129 college students. Results of a path analysis examining a mediation model indicated that the influence of night-sky interest on reading for pleasure was not mediated by the broad personality domain openness to…

  17. ESA Sky

    OpenAIRE

    Merin, Bruno

    2015-01-01

    The ESAC Science Data Centre, ESDC, is working on a science-driven discovery portal for all its astronomy missions with the provisional name Multi-Mission Interface. The first public release of this service will be demonstrated, featuring an interface for sky exploration and for single and multiple target searches. It requires no prior knowledge of any of the missions involved. From a technical point of view, the system offers all-sky projections of full mission datasets using a new-generatio...

  18. Fading Skies

    Science.gov (United States)

    Sio, Betsy Menson

    2009-01-01

    A sky fading from blue to white to red at the horizon, and water darkening from light to midnight blue. Strong diagonals slashing through the image, drawing a viewer's eyes deeper into the picture, and delicate trees poised to convey a sense of beauty. These are the fascinating strengths of the ukiyo-e woodblock prints of Japanese artist Ando…

  19. Google Sky: A Digital View of the Night Sky

    Science.gov (United States)

    Connolly, A. Scranton, R.; Ornduff, T.

    2008-11-01

    From its inception Astronomy has been a visual science, from careful observations of the sky using the naked eye, to the use of telescopes and photographs to map the distribution of stars and galaxies, to the current era of digital cameras that can image the sky over many decades of the electromagnetic spectrum. Sky in Google Earth (http://earth.google.com) and Google Sky (http://www.google.com/sky) continue this tradition, providing an intuitive visual interface to some of the largest astronomical imaging surveys of the sky. Streaming multi-color imagery, catalogs, time domain data, as well as annotating interesting astronomical sources and events with placemarks, podcasts and videos, Sky provides a panchromatic view of the universe accessible to anyone with a computer. Beyond a simple exploration of the sky Google Sky enables users to create and share content with others around the world. With an open interface available on Linux, Mac OS X and Windows, and translations of the content into over 20 different languages we present Sky as the embodiment of a virtual telescope for discovery and sharing the excitement of astronomy and science as a whole.

  20. Sky Surveys

    OpenAIRE

    Djorgovski, S. G.; Mahabal, A. A.; Drake, A.J.; Graham, M. J.; C. Donalek

    2012-01-01

    Sky surveys represent a fundamental data basis for astronomy. We use them to map in a systematic way the universe and its constituents, and to discover new types of objects or phenomena. We review the subject, with an emphasis on the wide-field imaging surveys, placing them in a broader scientific and historical context. Surveys are the largest data generators in astronomy, propelled by the advances in information and computation technology, and have transformed the ways in which astronomy is...

  1. Mapping correlation of a simulated dark matter source and a point source in the gamma-ray sky - Oral Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Gibson, Alexander [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-23

    In my research, I analyzed how two gamma-ray source models interact with one another when optimizing to fit data. This is important because it becomes hard to distinguish between the two point sources when they are close together or looking at low energy photons. The reason for the first is obvious, the reason why they become harder to distinguish at lower photon energies is the resolving power of the Fermi Gamma-Ray Space Telescope gets worse at lower energies. When the two point sources are highly correlated (hard to distinguish between), we need to change our method of statistical analysis. What I did was show that highly correlated sources have larger uncertainties associated with them, caused by an optimizer not knowing which point source’s parameters to optimize. I also mapped out where their is high correlation for 2 different theoretical mass dark matter point sources so that people analyzing them in the future knew where they had to use more sophisticated statistical analysis.

  2. Galaxy Evolution Insights from Spectral Modeling of Large Data Sets from the Sloan Digital Sky Survey

    Energy Technology Data Exchange (ETDEWEB)

    Hoversten, Erik A. [Johns Hopkins Univ., Baltimore, MD (United States)

    2007-10-01

    This thesis centers on the use of spectral modeling techniques on data from the Sloan Digital Sky Survey (SDSS) to gain new insights into current questions in galaxy evolution. The SDSS provides a large, uniform, high quality data set which can be exploited in a number of ways. One avenue pursued here is to use the large sample size to measure precisely the mean properties of galaxies of increasingly narrow parameter ranges. The other route taken is to look for rare objects which open up for exploration new areas in galaxy parameter space. The crux of this thesis is revisiting the classical Kennicutt method for inferring the stellar initial mass function (IMF) from the integrated light properties of galaxies. A large data set (~ 105 galaxies) from the SDSS DR4 is combined with more in-depth modeling and quantitative statistical analysis to search for systematic IMF variations as a function of galaxy luminosity. Galaxy Hα equivalent widths are compared to a broadband color index to constrain the IMF. It is found that for the sample as a whole the best fitting IMF power law slope above 0.5 M is Γ = 1.5 ± 0.1 with the error dominated by systematics. Galaxies brighter than around Mr,0.1 = -20 (including galaxies like the Milky Way which has Mr,0.1 ~ -21) are well fit by a universal Γ ~ 1.4 IMF, similar to the classical Salpeter slope, and smooth, exponential star formation histories (SFH). Fainter galaxies prefer steeper IMFs and the quality of the fits reveal that for these galaxies a universal IMF with smooth SFHs is actually a poor assumption. Related projects are also pursued. A targeted photometric search is conducted for strongly lensed Lyman break galaxies (LBG) similar to MS1512-cB58. The evolution of the photometric selection technique is described as are the results of spectroscopic follow-up of the best targets. The serendipitous discovery of two interesting blue compact dwarf galaxies is reported. These

  3. Night sky quality monitoring in existing and planned dark sky parks by digital cameras

    OpenAIRE

    Kolláth, Zoltán; Dömény, Anita

    2017-01-01

    A crucial part of the qualification of international dark sky places (IDSPs) is the objective measurement of night time sky luminance or radiance. Modern digital cameras provide an alternative way to perform all sky imaging either by a fisheye lens or by a mosaic image taken by a wide angle lens. Here we present a method for processing raw camera images to obtain calibrated measurements of sky quality. The comparison of the night sky quality of different European locations is also presented t...

  4. Daylighting analysis of rooflights through model measurements in the artificial sky

    Energy Technology Data Exchange (ETDEWEB)

    Filetoht, Levente I. [University of Technnology and Economics, Budapest, Hungary (Hungary)

    2000-07-01

    In investigating the daylighting of rooflights, it can be assumed that they are behaving as luminaires-having a major role in the lighting features of the interior space. Until now there is not enough precise information on these daylighting systems, and because of this, it is difficult to predict precisely the quality and quantity of illuminance and the light distribution in the interior. The exact behavior of the rooflights are complex and sophisticated. Their features are based on their geometry, reflectance and transmittance of their non-transparent, transparent and translucent surfaces. The effect of these features can not be predicted of calculated using the traditional mathematical methods. I am investigating roof-lighting systems taking into account the complex effects of their parts, using a completely new method based on a series of model measurements under artificial sky. Investigating the roof-light as a complex system which consist of relatively large surfaces and the effects of surfaces on other surfaces. Considering the different illuminance fields of the different types of roof-lighting systems. I will be able to determine the light distribution and efficiency of the system as well. The results of this research will lead to the development of a new computer software which is beyond the scope of this paper. [Spanish] Al investigar la iluminacion de luz de dia de luces de techo puede suponerse que se estan comportando como luminarias teniendo un papel principal en las caracteristicas de iluminacion del espacio interior. Hasta ahora no existe ninguna informacion precisa de estos sistemas de iluminacion de dia y a causa de ello es dificil predecir con precision la calidad y cantidad de iluminancia y la distribucion de la luz en el interior. El comportamiento exacto de las luces de techo es complejo y sofisticado. Sus caracteristicas estan basadas en su geometria, reflectancia y trasmitancia de sus superficies no transparentes, transparentes y

  5. Quest for safer skies: Modeling golden eagles and wind energy to reduce turbine risk

    Science.gov (United States)

    Todd Katzner; Tricia Miller; Scott. Stoleson

    2014-01-01

    In a patch of sky above Pennsylvania, a golden eagle moves languidly, never flapping but passing quickly as it cruises southward on a cushion of air. It is migrating to its wintering grounds after a season of breeding in Quebec. As part of a team studying eagles on a daily basis—a project supported by the U.S. Forest Service (USFS), West Virginia University,...

  6. MODELING OF THE ZODIACAL EMISSION FOR THE AKARI/IRC MID-INFRARED ALL-SKY DIFFUSE MAPS

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, Toru; Ishihara, Daisuke; Kaneda, Hidehiro; Nakamichi, Keichiro; Takaba, Sachi; Kobayashi, Hiroshi [Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan); Ootsubo, Takafumi [Graduate School of Arts and Sciences, The University of Tokyo, Meguro-ku, Tokyo 153-8902 (Japan); Pyo, Jeonghyun [Korea Astronomy and Space Science Institute, Daejeon 305-348 (Korea, Republic of); Onaka, Takashi, E-mail: kondo@u.phys.nagoya-u.ac.jp, E-mail: ishihara@u.phys.nagoya-u.ac.jp [Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2016-03-15

    The zodiacal emission, which is the thermal infrared (IR) emission from the interplanetary dust (IPD) in our solar system, has been studied for a long time. Nevertheless, accurate modeling of the zodiacal emission has not been successful to reproduce the all-sky spatial distribution of the zodiacal emission, especially in the mid-IR where the zodiacal emission peaks. Therefore, we aim to improve the IPD cloud model based on Kelsall et al., using the AKARI 9 and 18 μm all-sky diffuse maps. By adopting a new fitting method based on the total brightness, we have succeeded in reducing the residual levels after subtraction of the zodiacal emission from the AKARI data and thus in improving the modeling of the zodiacal emission. Comparing the AKARI and the COBE data, we confirm that the changes from the previous model to our new model are mostly due to model improvements, but not temporal variations between the AKARI and the COBE epoch, except for the position of the Earth-trailing blob. Our results suggest that the size of the smooth cloud, a dominant component in the model, is about 10% more compact than previously thought, and that the dust sizes are not large enough to emit blackbody radiation in the mid-IR. Furthermore, we detect a significant isotropically distributed IPD component, owing to an accurate baseline measurement with AKARI.

  7. Assimilation of clear sky Atmospheric Infrared Sounder radiances in short-term regional forecasts using community models

    Science.gov (United States)

    Lim, Agnes H. N.; Jung, James A.; Huang, Hung-Lung Allen; Ackerman, Steven A.; Otkin, Jason A.

    2014-01-01

    Regional assimilation experiments of clear-sky Atmospheric Infrared Sounder (AIRS) radiances were performed using the gridpoint statistical interpolation three-dimensional variational assimilation system coupled to the weather research and forecasting model. The data assimilation system and forecast model used in this study are separate community models; it cannot be assumed that the coupled systems work optimally. Tuning was performed on the data assimilation system and forecast model. Components tuned included the background error covariance matrix, the satellite radiance bias correction, the quality control procedures for AIRS radiances, the forecast model resolution, and the infrared channel selection. Assimilation metrics and diagnostics from the assimilation system were used to identify problems when combining separate systems. Forecasts initiated from analyses after assimilation were verified with model analyses, rawinsondes, nonassimilated satellite radiances, and 24 h-accumulated precipitation. Assimilation of clear sky AIRS radiances showed the largest improvement in temperature and radiance brightness temperature bias when compared with rawinsondes and satellite observations, respectively. Precipitation skill scores displayed minor changes with AIRS radiance assimilation. The 00 and 12 coordinated universal time (UTC) forecasts were typically of better quality than the 06 and 18 UTC forecasts, possibly due to the amount of AIRS data available for each assimilation cycle.

  8. Between Earth and Sky

    DEFF Research Database (Denmark)

    Carter, Adrian

    2009-01-01

    to rescue architecture from the sterile impasse of late-modernism. In his works the basic elements of lived space become present: the earth, the sky and the `between` of human existence." Jørn Utzon's architecture ranges from the modest to the monumental; from the Kingo courtyard houses, the finest...

  9. Dark-Skies Awareness

    Science.gov (United States)

    Walker, Constance E.

    2009-05-01

    The arc of the Milky Way seen from a truly dark location is part of our planet's natural heritage. More than one fifth of the world population, two thirds of the United States population and one half of the European Union population have already lost naked eye visibility of the Milky Way. This loss, caused by light pollution, is a serious and growing issue that impacts astronomical research, the economy, ecology, energy conservation, human health, public safety and our shared ability to see the night sky. For this reason, "Dark Skies” is a cornerstone project of the International Year of Astronomy. Its goal is to raise public awareness of the impact of artificial lighting on local environments by getting people worldwide involved in a variety of programs that: 1. Teach about dark skies using new technology (e.g., an activity-based planetarium show on DVD, podcasting, social networking on Facebook and MySpace, a Second Life presence) 2. Provide thematic events on light pollution at star parties and observatory open houses (Dark Skies Discovery Sites, Nights in the (National) Parks, Sidewalk Astronomy) 3. Organize events in the arts (e.g., a photography contest) 4. Involve citizen-scientists in naked-eye and digital-meter star hunting programs (e.g., GLOBE at Night, "How Many Stars?", the Great World Wide Star Count and the radio frequency interference equivalent: "Quiet Skies") and 5. Raise awareness about the link between light pollution and public health, economic issues, ecological consequences, energy conservation, safety and security, and astronomy (e.g., The Starlight Initiative, World Night in Defense of Starlight, International Dark Sky Week, International Dark-Sky Communities, Earth Hour, The Great Switch Out, a traveling exhibit, downloadable posters and brochures). The presentation will provide an update, describe how people can become involved and take a look ahead at the program's sustainability. For more information, visit www.darkskiesawareness.org.

  10. Fast All-Sky Radiation Model for Solar Applications (FARMS): A Brief Overview of Mechanisms, Performance, and Applications: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Yu; Sengupta, Manajit

    2016-06-01

    Solar radiation can be computed using radiative transfer models, such as the Rapid Radiation Transfer Model (RRTM) and its general circulation model applications, and used for various energy applications. Due to the complexity of computing radiation fields in aerosol and cloudy atmospheres, simulating solar radiation can be extremely time-consuming, but many approximations--e.g., the two-stream approach and the delta-M truncation scheme--can be utilized. To provide a new fast option for computing solar radiation, we developed the Fast All-sky Radiation Model for Solar applications (FARMS) by parameterizing the simulated diffuse horizontal irradiance and direct normal irradiance for cloudy conditions from the RRTM runs using a 16-stream discrete ordinates radiative transfer method. The solar irradiance at the surface was simulated by combining the cloud irradiance parameterizations with a fast clear-sky model, REST2. To understand the accuracy and efficiency of the newly developed fast model, we analyzed FARMS runs using cloud optical and microphysical properties retrieved using GOES data from 2009-2012. The global horizontal irradiance for cloudy conditions was simulated using FARMS and RRTM for global circulation modeling with a two-stream approximation and compared to measurements taken from the U.S. Department of Energy's Atmospheric Radiation Measurement Climate Research Facility Southern Great Plains site. Our results indicate that the accuracy of FARMS is comparable to or better than the two-stream approach; however, FARMS is approximately 400 times more efficient because it does not explicitly solve the radiative transfer equation for each individual cloud condition. Radiative transfer model runs are computationally expensive, but this model is promising for broad applications in solar resource assessment and forecasting. It is currently being used in the National Solar Radiation Database, which is publicly available from the National Renewable Energy

  11. Self-Presentation: A Conceptualization and Model.

    Science.gov (United States)

    Schlenker, Barry R.

    This paper provides a conceptual definition and model of self-presentational behavior. Self-presentation is defined as the attempt to control self-relevant images before real or imagined others. Several aspects of the definition are discussed along with the notion that people's self-presentations represent the choice of the most desirable images…

  12. Sky Surveys

    Science.gov (United States)

    Djorgovski, S. George; Mahabal, Ashish; Drake, Andrew; Graham, Matthew; Donalek, Ciro

    Sky surveys represent a fundamental data basis for astronomy. We usethem to map in a systematic way the universe and its constituents andto discover new types of objects or phenomena. We review the subject,with an emphasis on the wide-field, imaging surveys, placing them ina broader scientific and historical context. Surveys are now the largestdata generators in astronomy, propelled by the advances in informationand computation technology, and have transformed the ways in whichastronomy is done. This trend is bound to continue, especially with thenew generation of synoptic sky surveys that cover wide areas of the skyrepeatedly and open a new time domain of discovery. We describe thevariety and the general properties of surveys, illustrated by a number ofexamples, the ways in which they may be quantified and compared, andoffer some figures of merit that can be used to compare their scientificdiscovery potential. Surveys enable a very wide range of science, and that isperhaps their key unifying characteristic. As new domains of the observableparameter space open up thanks to the advances in technology, surveys areoften the initial step in their exploration. Some science can be done withthe survey data alone (or a combination of data from different surveys),and some require a targeted follow-up of potentially interesting sourcesselected from surveys. Surveys can be used to generate large, statisticalsamples of objects that can be studied as populations or as tracers of largerstructures to which they belong. They can be also used to discover orgenerate samples of rare or unusual objects and may lead to discoveriesof some previously unknown types. We discuss a general framework ofparameter spaces that can be used for an assessment and comparison ofdifferent surveys and the strategies for their scientific exploration. As we aremoving into the Petascale regime and beyond, an effective processing andscientific exploitation of such large data sets and data streams pose

  13. A Model of Triadic Post-Tonality for a Neoconservative Postmodern String Quartet by Sky Macklay

    Directory of Open Access Journals (Sweden)

    Zane Gillespie

    2017-09-01

    Full Text Available This article proposes a non-plural perspective on the analysis of triadic music, offering Sky Macklay’s Many Many Cadences as a case study. Part one is a discussion of the work’s harmony-voice leading nexus, followed by a discussion of the five conditions of correspondence as implied by this string quartet that articulate a single tonal identity. Part three focuses on a strictly kinematic analysis of the work’s harmonic progressions that evinces this identity and establishes its general applicability. In the final section, the data generated by this analysis conveys the inherent possibility of a single, all-encompassing kinematic, thereby pointing beyond the particularities of Many Many Cadences while informing my formal interpretation of the work.

  14. Polarization optics of the Brewster's dark patch visible on water surfaces versus solar height and sky conditions: theory, computer modeling, photography, and painting.

    Science.gov (United States)

    Takács, Péter; Barta, András; Pye, David; Horváth, Gábor

    2017-10-20

    When the sun is near the horizon, a circular band with approximately vertically polarized skylight is formed at 90° from the sun, and this skylight is only weakly reflected from the region of the water surface around the Brewster's angle (53° from the nadir). Thus, at low solar heights under a clear sky, an extended dark patch is visible on the water surface when one looks toward the north or south quarter perpendicular to the solar vertical. In this work, we study the radiance distribution of this so-called Brewster's dark patch (BDP) in still water as functions of the solar height and sky conditions. We calculate the pattern of reflectivity R of a water surface for a clear sky and obtain from this idealized situation the shape of the BDP. From three full-sky polarimetric pictures taken about a clear, a partly cloudy, and an overcast sky, we determine the R pattern and compose from that synthetic color pictures showing how the radiance distribution of skylight reflected at the water surface and the BDPs would look under these sky conditions. We also present photographs taken without a linearly polarizing filter about the BDP. Finally, we show a 19th century painting on which a river is seen with a dark region of the water surface, which can be interpreted as an artistic illustration of the BDP.

  15. Integrated high-resolution array CGH and SKY analysis of homozygous deletions and other genomic alterations present in malignant mesothelioma cell lines.

    Science.gov (United States)

    Klorin, Geula; Rozenblum, Ester; Glebov, Oleg; Walker, Robert L; Park, Yoonsoo; Meltzer, Paul S; Kirsch, Ilan R; Kaye, Frederic J; Roschke, Anna V

    2013-05-01

    High-resolution oligonucleotide array comparative genomic hybridization (aCGH) and spectral karyotyping (SKY) were applied to a panel of malignant mesothelioma (MMt) cell lines. SKY has not been applied to MMt before, and complete karyotypes are reported based on the integration of SKY and aCGH results. A whole genome search for homozygous deletions (HDs) produced the largest set of recurrent and non-recurrent HDs for MMt (52 recurrent HDs in 10 genomic regions; 36 non-recurrent HDs). For the first time, LINGO2, RBFOX1/A2BP1, RPL29, DUSP7, and CCSER1/FAM190A were found to be homozygously deleted in MMt, and some of these genes could be new tumor suppressor genes for MMt. Integration of SKY and aCGH data allowed reconstruction of chromosomal rearrangements that led to the formation of HDs. Our data imply that only with acquisition of structural and/or numerical karyotypic instability can MMt cells attain a complete loss of tumor suppressor genes located in 9p21.3, which is the most frequently homozygously deleted region. Tetraploidization is a late event in the karyotypic progression of MMt cells, after HDs in the 9p21.3 region have already been acquired. Published by Elsevier Inc.

  16. The Big Sky Model: A Regional Collaboration for Participatory Research on Environmental Health in the Rural West

    Science.gov (United States)

    Ward, Tony J.; Vanek, Diana; Marra, Nancy; Holian, Andrij; Adams, Earle; Jones, David; Knuth, Randy

    2010-01-01

    The case for inquiry-based, hands-on, meaningful science education continues to gain credence as an effective and appropriate pedagogical approach (Karukstis 2005; NSF 2000). An innovative community-based framework for science learning, hereinafter referred to as the Big Sky Model, successfully addresses these educational aims, guiding high school and tribal college students from rural areas of Montana and Idaho in their understanding of chemical, physical, and environmental health concepts. Students participate in classroom lessons and continue with systematic inquiry through actual field research to investigate a pressing, real-world issue: understanding the complex links between poor air quality and respiratory health outcomes. This article provides background information, outlines the procedure for implementing the model, and discusses its effectiveness as demonstrated through various evaluation tools. PMID:20428505

  17. Automatic Rotational Sky Quality Meter (R-SQM) Design and Software for Astronomical Observatories

    Science.gov (United States)

    Dogan, E.; Ozbaldan, E. E.; Shameoni, Niaei M.; Yesilyaprak, C.

    2016-12-01

    We have presented the new design of Sky Quality Meter (SQM) device that is an automatic rotational model of sky quality meter (R-SQM) carried out by DAG (Eastern Anatolia Observatory) Technical Team. R-SQM is required for determining the long-term changes of sky quality of an astronomical observatory and consists of four SQM devices mounted on a rotating shaft with different angles for scanning all sky. This system is controlled by a Raspberry Pi control card and a step motor with its driver and a special software.

  18. VLITE Surveys the Sky: A 340 MHz Companion to the VLA Sky Survey (VLASS)

    Science.gov (United States)

    Peters, Wendy; Clarke, Tracy; Brisken, Walter; Cotton, William; Richards, Emily E.; Giacintucci, Simona; Kassim, Namir

    2018-01-01

    The VLA Low Band Ionosphere and Transient Experiment (VLITE; ) is a commensal observing system on the Karl G. Janksy Very Large Array (VLA) which was developed by the Naval Research Laboratory and NRAO. A 64 MHz sub-band from the prime focus 240-470 MHz dipoles is correlated during nearly all regular VLA observations. VLITE uses dedicated samplers and fibers, as well as a custom designed, real-time DiFX software correlator, and requires no additional resources from the VLA system running the primary science program. The experiment has been operating since November 2014 with 10 antennas; a recent expansion in summer 2017 increased that number to 16 and more than doubled the number of baselines.The VLA Sky Survey (VLASS; https://science.nrao.edu/science/surveys/vlass >), is an ongoing survey of the entire sky visible to the VLA at a frequency of 2-4 GHz. The observations are made using an "on-the-fly" (OTF) continuous RA scanning technique which fills in the sky by observing along rows of constant declination. VLITE breaks the data into 2-second integrations and correlates these at a central position every 1.5 degrees. All data for each correlator position is imaged separately, corrected and weighted by an appropriately elongated primary beam model, and then combined in the image plane to create a mosaic of the sky. A catalog of the sources is extracted to provide a 340 MHz sky model.We present preliminary images and catalogs from the 2017 VLASS observations which began in early September, 2017, and continued on a nearly daily basis throughout the fall. In addition to providing a unique sky model at 340 MHz, these data complement VLASS by providing spectral indices for all cataloged sources.

  19. Sky cover from MFRSR observations

    Directory of Open Access Journals (Sweden)

    E. Kassianov

    2011-07-01

    Full Text Available The diffuse all-sky surface irradiances measured at two nearby wavelengths in the visible spectral range and their modeled clear-sky counterparts are the main components of a new method for estimating the fractional sky cover of different cloud types, including cumuli. The performance of this method is illustrated using 1-min resolution data from a ground-based Multi-Filter Rotating Shadowband Radiometer (MFRSR. The MFRSR data are collected at the US Department of Energy Atmospheric Radiation Measurement (ARM Climate Research Facility (ACRF Southern Great Plains (SGP site during the summer of 2007 and represent 13 days with cumuli. Good agreement is obtained between estimated values of the fractional sky cover and those provided by a well-established independent method based on broadband observations.

  20. Simulating the WFXT sky.

    Science.gov (United States)

    Tozzi, P.; Santos, J.; Yu, H.; Bignamini, A.; Rosati, P.; Borgani, S.; Campana, S.; Conconi, P.; Gilli, R.; Paolillo, M.; Ptak, A.; WFXT Team

    We investigate the scientific impact of the Wide Field X-ray Telescope mission. We present simulated images and spectra of X-ray sources as observed from the three surveys planned for the nominal 5-year WFXT lifetime. The goal of these simulations is to provide WFXT images of the extragalactic sky in different energy bands based on accurate description of AGN populations, normal and star forming galaxies, groups and clusters of galaxies. The images are realized using a detailed PSF model, instrumental and physical backgrounds/foregrounds, accurate model of the effective area and the related vignetting effect. The simulated images can be used to evaluate the flux limits for detection of point and extended sources, the effect of source confusion at very faint fluxes, and in general the efficiency of detection algorithms. We also simulate the spectra of the detected sources, in order to address specific science topics which are unique to WFXT. Among them, we focus on the characterization of the Intra Cluster Medium (ICM) of high-z clusters, and in particular on the measurement of the redshift from the ICM spectrum in order to build a cosmological sample of galaxy clusters. The end-to-end simulation procedure presented here, is a valuable tool in optimizing the mission design, characterizing the WFXT discovery space and verifying the connection between mission requirements and scientific goals. Thanks to this effort, we can conclude on firm basis that an X-ray mission optimized for surveys like WFXT is necessary to bring X-ray astronomy at the level of the optical, IR, submm and radio wavebands as foreseen in the coming decade.

  1. The Sky at Night

    CERN Document Server

    Moore, Patrick

    2010-01-01

    For more than 50 years now Sir Patrick Moore has presented the BBC Television series Sky at Night; not a month has been missed – a record for any television series, and a record which may never be broken. Every three years or so a book is published covering the main events in both astronomy and space research. This is the 13th volume, not only a record of the programmes but also of the great advances and discoveries during the period covered - eclipses, comets, and the strange chemical lakes of Titan, for instance, but also anniversaries such as the fifteenth “birthday” of the Hubble Space Telescope, and not forgetting the programme celebrating the Sky at Night’s 50th year, attended by astronaut Piers Sellars and many others who appeared on the programme over the years. All the chapters are self-contained, and fully illustrated. In this new Sky at Night book you will find much to entertain you. It will appeal to amateurs and professionals alike.

  2. Daytime Water Detection Based on Sky Reflections

    Science.gov (United States)

    Rankin, Arturo; Matthies, Larry; Bellutta, Paolo

    2011-01-01

    A water body s surface can be modeled as a horizontal mirror. Water detection based on sky reflections and color variation are complementary. A reflection coefficient model suggests sky reflections dominate the color of water at ranges > 12 meters. Water detection based on sky reflections: (1) geometrically locates the pixel in the sky that is reflecting on a candidate water pixel on the ground (2) predicts if the ground pixel is water based on color similarity and local terrain features. Water detection has been integrated on XUVs.

  3. Searching for beyond the minimal supersymmetric standard model at the laboratory and in the sky

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ju Min

    2010-09-15

    We study the collider signals as well as Dark Matter candidates in supersymmetric models. We show that the collider signatures from a supersymmetric Grand Unification model based on the SO(10) gauge group can be distinguishable from those from the (constrained) minimal supersymmetric Standard Model, even though they share some common features. The N=2 supersymmetry has the characteristically distinct phenomenology, due to the Dirac nature of gauginos, as well as the extra adjoint scalars. We compute the cold Dark Matter relic density including a class of one-loop corrections. Finally, we discuss the detectability of neutralino Dark Matter candidate of the SO(10) model by the direct and indirect Dark Matter search experiments. (orig.)

  4. Night sky luminance under clear sky conditions: Theory vs. experiment

    Science.gov (United States)

    Kocifaj, Miroslav

    2014-05-01

    Sky glow is caused by both natural phenomena and factors of anthropogenic origin, and of the latter ground-based light sources are the most important contributors for they emit the spatially linked spectral radiant intensity distribution of artificial light sources, which are further modulated by local atmospheric optics and perceived as the diffuse light of a night sky. In other words, sky glow is closely related to a city's shape and pattern of luminaire distribution, in practical effect an almost arbitrary deployment of random orientation of heterogeneous electrical light sources. Thus the luminance gradation function measured in a suburban zone or near the edges of a city is linked to the City Pattern or vice versa. It is shown that clear sky luminance/radiance data recorded in an urban area can be used to retrieve the bulk luminous/radiant intensity distribution if some a-priori information on atmospheric aerosols is available. For instance, the single scattering albedo of aerosol particles is required under low turbidity conditions, as demonstrated on a targeted experiment in the city of Frýdek-Mistek. One of the main advantages of the retrieval method presented in this paper is that the single scattering approximation is satisfactorily accurate in characterizing the light field near the ground because the dominant contribution to the sky glow has originated from beams propagated along short optical paths.

  5. Dark Sky Protection and Education - Izera Dark Sky Park

    Science.gov (United States)

    Berlicki, Arkadiusz; Kolomanski, Sylwester; Mrozek, Tomasz; Zakowicz, Grzegorz

    2015-08-01

    Darkness of the night sky is a natural component of our environment and should be protected against negative effects of human activities. The night darkness is necessary for balanced life of plants, animals and people. Unfortunately, development of human civilization and technology has led to the substantial increase of the night-sky brightness and to situation where nights are no more dark in many areas of the World. This phenomenon is called "light pollution" and it can be rank among such problems as chemical pollution of air, water and soil. Besides the environment, the light pollution can also affect e.g. the scientific activities of astronomers - many observatories built in the past began to be located within the glow of city lights making the night observations difficult, or even impossible.In order to protect the natural darkness of nights many so-called "dark sky parks" were established, where the darkness is preserved, similar to typical nature reserves. The role of these parks is not only conservation but also education, supporting to make society aware of how serious the problem of the light pollution is.History of the dark sky areas in Europe began on November 4, 2009 in Jizerka - a small village situated in the Izera Mountains, when Izera Dark Sky Park (IDSP) was established - it was the first transboundary dark sky park in the World. The idea of establishing that dark sky park in the Izera Mountains originated from a need to give to the society in Poland and Czech Republic the knowledge about the light pollution. Izera Dark Sky Park is a part of the astro-tourism project "Astro Izery" that combines tourist attraction of Izera Valley and astronomical education under the wonderful starry Izera sky. Besides the IDSP, the project Astro Izery consists of the set of simple astronomical instruments (gnomon, sundial), natural educational trail "Solar System Model", and astronomical events for the public. In addition, twice a year we organize a 3-4 days

  6. Nightscape Photography Reclaims the Natural Sky

    Science.gov (United States)

    Tafreshi, Babak

    2015-08-01

    Nightscape photos and timelapse videos, where the Earth & sky are framed together with an astronomical purpose, support the dark skies activities by improving public awareness. TWAN or The World at Night program (www.twanight.org) presents the world's best collection of such landscape astrophotos and aims to introduce the night sky as a part of nature, an essential element of our living environment besides being the astronomers lab. The nightscape images also present views of our civilizations landmarks, both natural and historic sites, against the night-time backdrop of stars, planets, and celestial events. In this context TWAN is a bridge between art, science and culture.TWAN images contribute to programs such as the Dark Sky Parks by the International Dark Sky Association or Starlight reserves by assisting local efforts in better illustrating their dark skies and by producing stunning images that not only educate the local people on their night sky heritage also communicate with the governments that are responsible to support the dark sky area.Since 2009 TWAN organizes the world's largest annual photo contest on nightscape imaging, in collaboration with the Dark Skies Awareness, National Optical Astronomy Observatory, and Astronomers Without Borders. The International Earth & Sky Photo Contest promotes the photography that documents the beauty of natural skies against the problem of light pollution. In 2014 the entries received from about 50 countries and the contest result news was widely published in the most popular sources internationally.*Babak A. Tafreshi is a photographer and science communicator. He is the creator of The World At Night program, and a contributing photographer to the National Geographic, Sky&Telescope magazine, and the European Southern Observatory. http://twanight.org/tafreshi

  7. LSST Site: Sky Brightness Data

    Science.gov (United States)

    Burke, Jamison; Claver, Charles

    2015-01-01

    The Large Synoptic Survey Telescope (LSST) is an upcoming robotic survey telescope. At the telescope site on Cerro Pachon in Chile there are currently three photodiodes and a Canon camera with a fisheye lens, and both the photodiodes and Canon monitor the night sky continuously. The NIST-calibrated photodiodes directly measure the flux from the sky, and the sky brightness can also be obtained from the Canon images via digital aperture photometry. Organizing and combining the two data sets gives nightly information of the development of sky brightness across a swath of the electromagnetic spectrum, from blue to near infrared light, and this is useful for accurately predicting the performance of the LSST. It also provides data for models of moonlight and twilight sky brightness. Code to accomplish this organization and combination was successfully written in Python, but due to the backlog of data not all of the nights were processed by the end of the summer.Burke was supported by the NOAO/KPNO Research Experiences for Undergraduates (REU) Program which is funded by the National Science Foundation Research Experiences for Undergraduates Program (AST-1262829).

  8. Network based sky Brightness Monitor

    Science.gov (United States)

    McKenna, Dan; Pulvermacher, R.; Davis, D. R.

    2009-01-01

    We have developed and are currently testing an autonomous 2 channel photometer designed to measure the night sky brightness in the visual wavelengths over a multi-year campaign. The photometer uses a robust silicon sensor filtered with Hoya CM500 glass. The Sky brightness is measured every minute at two elevation angles typically zenith and 20 degrees to monitor brightness and transparency. The Sky Brightness monitor consists of two units, the remote photometer and a network interface. Currently these devices use 2.4 Ghz transceivers with a free space range of 100 meters. The remote unit is battery powered with day time recharging using a solar panel. Data received by the network interface transmits data via standard POP Email protocol. A second version is under development for radio sensitive areas using an optical fiber for data transmission. We will present the current comparison with the National Park Service sky monitoring camera. We will also discuss the calibration methods used for standardization and temperature compensation. This system is expected to be deployed in the next year and be operated by the International Dark Sky Association SKYMONITOR project.

  9. Diagnosis of clear sky ultraviolet radiation for Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lemus Deschamps, L. [Bureau of Meteorology Research Centre (Australia); Galindo, I.; Solano, R.; Elizalde, A.T.; Fonseca, J. [Centro Universitario de Investigaciones en Ciencias del Ambiente, University of Colima (Mexico)

    2002-07-01

    A discrete-ordinate radiative transfer model is employed to develop a regional clear sky ultraviolet (UV) diagnosis system. The clear sky UV radiation, weighted by the spectral sensitivity of human skin is calculated using the Total Ozone Mapping Spectrometer (TOMS) data sets. Examples of the geographical clear sky UV Index distributions are presented and the model results are compared with surface UV measurements from University of Colima for 1999. [Spanish] Utilizando un modelo de transferencia de radiacion de ordenadas discretas se desarrolla un sistema para el diagnostico de la distribucion de radiacion ultravioleta para cielo despejado en la Republica Mexicana. La radiacion para cielo despejado se obtiene utilizando la respuesta espectral de la piel humana y los datos de satelite de ozono total registrados por el espectrometro TOMS. Se presentan ejemplos del Indice de radiacion ultravioleta (UV Index) calculados con el modelo y se comparan con las mediciones en superficie obtenidas en la Universidad de Colima durante 1999.

  10. Accounting for the effects of sastrugi in the CERES clear-sky Antarctic shortwave angular distribution models

    Science.gov (United States)

    Corbett, J.; Su, W.

    2015-08-01

    The Cloud and the Earth's Radiant Energy System (CERES) instruments on NASA's Terra, Aqua and Soumi NPP satellites are used to provide a long-term measurement of Earth's energy budget. To accomplish this, the radiances measured by the instruments must be inverted to fluxes by the use of a scene-type-dependent angular distribution model (ADM). For permanent snow scenes over Antarctica, shortwave (SW) ADMs are created by compositing radiance measurements over the full viewing zenith and azimuth range. However, the presence of small-scale wind blown roughness features called sastrugi cause the BRDF (bidirectional reflectance distribution function) of the snow to vary significantly based upon the solar azimuth angle and location. This can result in monthly regional biases between -12 and 7.5 Wm-2 in the inverted TOA (top-of-atmosphere) SW flux. The bias is assessed by comparing the CERES shortwave fluxes derived from nadir observations with those from all viewing zenith angles, as the sastrugi affect fluxes inverted from the oblique viewing angles more than for the nadir viewing angles. In this paper we further describe the clear-sky Antarctic ADMs from Su et al. (2015). These ADMs account for the sastrugi effect by using measurements from the Multi-Angle Imaging Spectro-Radiometer (MISR) instrument to derive statistical relationships between radiance from different viewing angles. We show here that these ADMs reduce the bias and artifacts in the CERES SW flux caused by sastrugi, both locally and Antarctic-wide. The regional monthly biases from sastrugi are reduced to between -5 and 7 Wm-2, and the monthly-mean biases over Antarctica are reduced by up to 0.64 Wm-2, a decrease of 74 %. These improved ADMs are used as part of the Edition 4 CERES SSF (Single Scanner Footprint) data.

  11. Dark Skies are a Universal Resource. So are Quiet Skies!

    Science.gov (United States)

    Maddalena, Ronald J.; Heatherly, S.

    2008-05-01

    You've just purchased your first telescope. But where to set it up? Certainly not a WalMart parking lot. Too much light pollution! In the same way that man-made light obscures our night sky and blinds ground-based optical telescopes, man-made radio signals blind radio telescopes as well. NRAO developed the Quiet Skies project to increase awareness of radio frequency interference (RFI) and radio astronomy in general by engaging students in local studies of RFI. To do that we created a sensitive detector which measures RFI. We produced 20 of these, and assembled kits containing detectors and supplementary materials for loan to schools. Students conduct experiments to measure the properties of RFI in their area, and input their measurements into a web-based data base. The Quiet Skies project is a perfect complement to the IYA Dark Skies Awareness initiative. We hope to place 500 Quiet Skies detectors into the field through outreach to museums and schools around the world. Should we be successful, we will sustain this global initiative via a continuing loan program. One day we hope to have a publicly generated image of the Earth which shows RFI much as the Earth at Night image illustrates light pollution. The poster will present the components of the project in detail, including our plans for IYA, and various low-cost alternative strategies for introducing RFI and radio astronomy to the public. We will share the results of some of the experiments already being performed by high school students. Development of the Quiet Skies project was funded by a NASA IDEAS grant. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  12. The Global Earthquake Model - Past, Present, Future

    Science.gov (United States)

    Smolka, Anselm; Schneider, John; Stein, Ross

    2014-05-01

    The Global Earthquake Model (GEM) is a unique collaborative effort that aims to provide organizations and individuals with tools and resources for transparent assessment of earthquake risk anywhere in the world. By pooling data, knowledge and people, GEM acts as an international forum for collaboration and exchange. Sharing of data and risk information, best practices, and approaches across the globe are key to assessing risk more effectively. Through consortium driven global projects, open-source IT development and collaborations with more than 10 regions, leading experts are developing unique global datasets, best practice, open tools and models for seismic hazard and risk assessment. The year 2013 has seen the completion of ten global data sets or components addressing various aspects of earthquake hazard and risk, as well as two GEM-related, but independently managed regional projects SHARE and EMME. Notably, the International Seismological Centre (ISC) led the development of a new ISC-GEM global instrumental earthquake catalogue, which was made publicly available in early 2013. It has set a new standard for global earthquake catalogues and has found widespread acceptance and application in the global earthquake community. By the end of 2014, GEM's OpenQuake computational platform will provide the OpenQuake hazard/risk assessment software and integrate all GEM data and information products. The public release of OpenQuake is planned for the end of this 2014, and will comprise the following datasets and models: • ISC-GEM Instrumental Earthquake Catalogue (released January 2013) • Global Earthquake History Catalogue [1000-1903] • Global Geodetic Strain Rate Database and Model • Global Active Fault Database • Tectonic Regionalisation Model • Global Exposure Database • Buildings and Population Database • Earthquake Consequences Database • Physical Vulnerabilities Database • Socio-Economic Vulnerability and Resilience Indicators • Seismic

  13. Optical Sky Brightness at Dome C, Antarctica

    Science.gov (United States)

    Kenyon, S.; Storey, J. W. V.; Burton, M. G.

    2006-08-01

    Dome C, Antarctica is a prime site for astronomical observations in terms of climate, wind speeds and turbulence. The infrared and terahertz sky backgrounds are the lowest of any inhabited place on Earth. However, at present little is known about the optical sky brightness and atmospheric extinction. Using a variety of modelling techniques together with data from the South Pole, we estimate the brightness of the night sky including the contributions from scattered sunlight, moonlight, aurorae, airglow, zodiacal light and artificial sources. We compare our results to another prime astronomical site, Mauna Kea. We find moonlight has significantly less effect at Dome C than at Mauna Kea. Aurorae are expected to have a minor impact at both sites, and zodiacal light is expected to be less at Dome C than at Mauna Kea. Airglow emissions at Dome C are expected to be similar to those at temperate sites. With proper planning, artificial sources of light pollution should be non-existent. The overall atmospheric extinction, or opacity, is expected to be the minimum possible. We conclude that Dome C is a very promising site not only for infrared and terahertz astronomy, but for optical astronomy as well..

  14. Model for Presenting Resources in Scholar's Portal

    Science.gov (United States)

    Feeney, Mary; Newby, Jill

    2005-01-01

    Presenting electronic resources to users through a federated search engine introduces unique opportunities and challenges to libraries. This article reports on the decision-making tools and processes used for selecting collections of electronic resources by a project team at the University of Arizona (UA) Libraries for the Association of Research…

  15. Evaluation of three empirical reference evapotranspiration models at a tropical station under three sky conditions using two solar radiation estimation methods

    Directory of Open Access Journals (Sweden)

    C. J. Ejieji

    2012-08-01

    Full Text Available An existing solar radiation model developed at Ilorin and found to be more reliable than Angstrom-type and Hargreaves solar radiation equations was used in the FAO Penman-Monteith reference evapotranspiration model (FAOPM to obtain daily reference crop evapotranspiration (ETo for a 32-year (1970 to 2001 period. The number of days having all the required input meteorological data was 9335. The sky conditions of the days were classified as clear, partially cloudy or cloudy depending on the cloudiness index i.e. the ratio of diffuse solar radiation to total solar radiation. The ETo values obtained with FAOPM were compared with predictions of three simpler empirical ETo models namely the Hargreaves (HGRV, Jensen and Haise (JHSE and Blaney-Morin-Nigeria (BMN models. When the more reliable solar radiation model was used in HGRV and JHSE, their performances were better than when the solar radiation equation of Hargreaves was used. Generally the three simpler models overpredicted ETo. The bias, root mean square difference (RSMD and absolute error of prediction deteriorated with sky cloudiness when the solar radiation equation of Hargreaves was used. Linear regression equations with zero intercepts were developed for the estimation of FAOPM predictions from those of the simpler ETo models. The regression equations relating the predictions of FAOPM to those of HGRV generally yielded the highest coefficients of determination and the lowest standard errors of regression. The predictions of HGRV were also the closest to the corresponding FAOPM predictions under the various sky conditions. Based on the outcome of the regression analysis and the ease of application of HGRV, the FAOPM-versus-HGRV regression equations were recommended for the estimation of FAOPM predictions of daily ETo when the use of FAOPM is necessary but not feasible because of incomplete input data.

  16. Anthropogenic changes in the surface all-sky UV-B radiation through 1850–2005 simulated by an Earth system model

    OpenAIRE

    Yokohata, T.; Sudo, K; Takemura, T.; Watanabe, S.; Kawase, H.

    2012-01-01

    The historical anthropogenic change in the surface all-sky UV-B (solar ultraviolet: 280–315 nm) radiation through 1850–2005 is evaluated using an Earth system model. Responses of UV-B dose to anthropogenic changes in ozone and aerosols are separately evaluated using a series of historical simulations including/excluding these changes. Increases in these air pollutants cause reductions in UV-B transmittance, which occur gradually/rapidly before/after 1950 in and downwind of industrial a...

  17. Anthropogenic changes in the surface all-sky UV-B radiation through 1850–2005 simulated by an Earth system model

    OpenAIRE

    Watanabe, S.; Takemura, T.; Sudo, K; Yokohata, T.; Kawase, H.

    2012-01-01

    The historical anthropogenic change in the surface all-sky UV-B (solar ultraviolet: 280–315 nm) radiation through 1850–2005 is evaluated using an Earth system model. Responses of UV-B dose to anthropogenic changes in ozone and aerosols are separately evaluated using a series of historical simulations including/excluding these changes. Increases in these air pollutants cause reductions in UV-B transmittance, which occur gradually/rapidly before/after 1950 in and downwind of industrial and defo...

  18. Sky Subtraction with Fiber-Fed Spectrograph

    Science.gov (United States)

    Rodrigues, Myriam

    2017-09-01

    "Historically, fiber-fed spectrographs had been deemed inadequate for the observation of faint targets, mainly because of the difficulty to achieve high accuracy on the sky subtraction. The impossibility to sample the sky in the immediate vicinity of the target in fiber instruments has led to a commonly held view that a multi-object fibre spectrograph cannot achieve an accurate sky subtraction under 1% contrary to their slit counterpart. The next generation of multi-objects spectrograph at the VLT (MOONS) and the planed MOS for the E-ELT (MOSAIC) are fiber-fed instruments, and are aimed to observed targets fainter than the sky continuum level. In this talk, I will present the state-of-art on sky subtraction strategies and data reduction algorithm specifically developed for fiber-fed spectrographs. I will also present the main results of an observational campaign to better characterise the sky spatial and temporal variations ( in particular the continuum and faint sky lines)."

  19. Close to the Sky

    Science.gov (United States)

    2007-11-01

    Today, a new ALMA outreach and educational book was publicly presented to city officials of San Pedro de Atacama in Chile, as part of the celebrations of the anniversary of the Andean village. ESO PR Photo 50a/07 ESO PR Photo 50a/07 A Useful Tool for Schools Entitled "Close to the sky: Biological heritage in the ALMA area", and edited in English and Spanish by ESO in Chile, the book collects unique on-site observations of the flora and fauna of the ALMA region performed by experts commissioned to investigate it and to provide key initiatives to protect it. "I thank the ALMA project for providing us a book that will surely be a good support for the education of children and youngsters of San Pedro de Atacama. Thanks to this publication, we expect our rich flora and fauna to be better known. I invite teachers and students to take advantage of this educational resource, which will be available in our schools", commented Ms. Sandra Berna, the Mayor of San Pedro de Atacama, who was given the book by representatives of the ALMA global collaboration project. Copies of the book 'Close to the sky' will be donated to all schools in the area, as a contribution to the education of students and young people in northern Chile. "From the very beginning of the project, ALMA construction has had a firm commitment to environment and local culture, protecting unique flora and fauna species and preserving old estancias belonging to the Likan Antai culture," said Jacques Lassalle, who represented ALMA at the hand-over. "Animals like the llama, the fox or the condor do not only live in the region where ALMA is now being built, but they are also key elements of the ancient Andean constellations. In this sense they are part of the same sky that will be explored by ALMA in the near future." ESO PR Photo 50c/07 ESO PR Photo 50c/07 Presentation of the ALMA book The ALMA Project is a giant, international observatory currently under construction on the high-altitude Chajnantor site in Chile

  20. Tropospheric haze and colors of the clear daytime sky.

    Science.gov (United States)

    Lee, Raymond L

    2015-02-01

    To casual observers, haze's visible effects on clear daytime skies may seem mundane: significant scattering by tropospheric aerosols visibly (1) reduces the luminance contrast of distant objects and (2) desaturates sky blueness. However, few published measurements of hazy-sky spectra and chromaticities exist to compare with these naked-eye observations. Hyperspectral imaging along sky meridians of clear and hazy skies at one inland and two coastal sites shows that they have characteristic colorimetric signatures of scattering and absorption by haze aerosols. In addition, a simple spectral transfer function and a second-order scattering model of skylight reveal the net spectral and colorimetric effects of haze.

  1. The role of aerosol absorption in driving clear-sky solar dimming over East Asia

    Science.gov (United States)

    Persad, Geeta G.; Ming, Yi; Ramaswamy, V.

    2014-09-01

    Surface-based observations indicate a significant decreasing trend in clear-sky downward surface solar radiation (SSR) over East Asia since the 1960s. This "dimming" is thought to be driven by the region's long-term increase in aerosol emissions, but little work has been done to quantify the underlying physical mechanisms or the contribution from aerosol absorption within the atmospheric column. Given the distinct climate impacts that absorption-driven dimming may produce, this constitutes an important, but thus far rather neglected, line of inquiry. We examine experiments conducted in the Geophysical Fluid Dynamics Laboratory's atmospheric general circulation models, AM2.1 and AM3, in order to analyze the model-simulated East Asian clear-sky SSR trends. We also use the models' stand-alone radiation module to examine the contribution from various aerosol characteristics in the two models (such as burden, mixing state, hygroscopicity, and seasonal distribution) to the trends. Both models produce trends in clear-sky SSR that are comparable to that observed but via disparate mechanisms. Despite their different aerosol characteristics, the models produce nearly identical increases in aerosol absorption since the 1960s, constituting as much as half of the modeled clear-sky dimming. This is due to a compensation between the differences in aerosol column burden and mixing state assumed in the two models, i.e., plausible clear-sky SSR simulations can be achieved via drastically different aerosol parameterizations. Our novel results indicate that trends in aerosol absorption drive a large portion of East Asian clear-sky solar dimming in the models presented here and for the time periods analyzed and that mechanistic analysis of the factors involved in aerosol absorption is an important diagnostic in evaluating modeled clear-sky solar dimming trends.

  2. Preserving Dark Skies: Do Astronomers Care?

    Science.gov (United States)

    Davis, D. R.; Crawford, D. L.

    2001-12-01

    Ground based telescopes are, even in this era of planetary missions and space telescopes, the dominant source of data on solar system objects. Yet many of the premier observing sites in the world are threatened by increasing artificial light that is scattered into the sky - light pollution. World class observing sites such as Mt. Wilson have long since lost the ability to do cutting edge faint object science and observatories in Southern Arizona have been recently threatened - the Canoa Ranch development being the most recent example. Yet there are actions that can be taken to preserve dark skies, not only for astronomy, but also for the benefit of all humanity. Lead by astronomers, effective outdoor lighting codes have been produced and adopted by many jurisdictional authorities. Advocacy organizations such as the International Dark-sky Association (IDA) distribute educational material on how to preserve dark skies through good outdoor lighting practices. Other institutions, such as the National Park Service, are realizing that dark skies are an integral part of the wilderness experience and are taking steps to preserve the quality of their skies. However, the primary beneficaries of dark sky preservation efforts, namely the ground based astronomical community, have largely failed to become involved in efforts to preserve dark skies. For example, only a few percent of the membership of the American Astronomical Society is active in light pollution work or is even a member of IDA. In this presentation, Iwe will outline what is being done locally to preserve dark skies througout the world. In addition, some observations on the level of support from the astronomical community will be offered.

  3. Astronomy Education Under Dark Skies

    Science.gov (United States)

    Cecylia Molenda-Zakowicz, Joanna

    2015-08-01

    We have been providing professional support for the high school students and the astronomy teachers since 2007. Our efforts include organizing astronomy events that take from several hours, like, e.g., watching the transit of Venus, to several days, like the workshops organized in the framework of the projects 'School Workshops on Astronomy' (SWA) and 'Wygasz'.The SWA and Wygasz workshops include presentations by experts in astronomy and space science research, presentations prepared by students being supervised by those experts, hands-on interactive experience in the amateur astrophotography, various pencil-and-paper exercises, and other practical activities. We pay particular attention to familiarize the teachers and students with the idea and the necessity of protecting the dark sky. The format of these events allows also for some time for teachers to share ideas and best practices in teaching astronomy.All those activities are organized either in the Izera Dark-Sky Park in Poland or in other carefuly selected locations in which the beauty of the dark night sky can be appreciated.

  4. Single-footprint retrievals for AIRS using a fast TwoSlab cloud-representation model and the SARTA all-sky infrared radiative transfer algorithm

    Directory of Open Access Journals (Sweden)

    S. DeSouza-Machado

    2018-01-01

    Full Text Available One-dimensional variational retrievals of temperature and moisture fields from hyperspectral infrared (IR satellite sounders use cloud-cleared radiances (CCRs as their observation. These derived observations allow the use of clear-sky-only radiative transfer in the inversion for geophysical variables but at reduced spatial resolution compared to the native sounder observations. Cloud clearing can introduce various errors, although scenes with large errors can be identified and ignored. Information content studies show that, when using multilayer cloud liquid and ice profiles in infrared hyperspectral radiative transfer codes, there are typically only 2–4 degrees of freedom (DOFs of cloud signal. This implies a simplified cloud representation is sufficient for some applications which need accurate radiative transfer. Here we describe a single-footprint retrieval approach for clear and cloudy conditions, which uses the thermodynamic and cloud fields from numerical weather prediction (NWP models as a first guess, together with a simple cloud-representation model coupled to a fast scattering radiative transfer algorithm (RTA. The NWP model thermodynamic and cloud profiles are first co-located to the observations, after which the N-level cloud profiles are converted to two slab clouds (TwoSlab; typically one for ice and one for water clouds. From these, one run of our fast cloud-representation model allows an improvement of the a priori cloud state by comparing the observed and model-simulated radiances in the thermal window channels. The retrieval yield is over 90 %, while the degrees of freedom correlate with the observed window channel brightness temperature (BT which itself depends on the cloud optical depth. The cloud-representation and scattering package is benchmarked against radiances computed using a maximum random overlap (RMO cloud scheme. All-sky infrared radiances measured by NASA's Atmospheric Infrared Sounder (AIRS and NWP

  5. Presentation

    Directory of Open Access Journals (Sweden)

    Eduardo Vicente

    2013-06-01

    effectivities more than a number of fixed essential characteristics. Luiz Artur Ferrareto (UFRGS, undertaking a theoretical proposal for categorizing radio content in four different levels of planning (segment, form, programming and content itself tries to “compare and contrast the practices of Brazilian commercial broadcasting companies to those used on the radio in the United States, a reference market for our national entrepreneurs”. Madalena Oliveira (University of Minho focuses on the current stage of communication researches in Portugal reflecting on the challenges for studying a culture based on listening in times of looking. Marko Ala-Fossi, (University of Tampere beginning with the statement that “radio evolution greatly depends not only on the cultural context of a country but also on the whole social, political, economic development of societies” gives us a projection on radio development around the world for the next decades. Closing the dossier, Rafael Duarte Oliveira Venancio (UFU assuming radio as language by definition and not as a device understands it as a section and an operating model in such language as it intersects the world. Another six articles, not enrolled in the dossier, round the edition off. Fernando de Tacca debates the category of “photocine” recurring to three recent Spanish productions. Gustavo Souza investigates the possibility of identifying a point of view in documentary movies while establishing a debate that joins the materialities of image and sound with the subjectivity resulting from interpretation. Vinicius Bandeira develops on the special duplicity present in the movies between what is and what is not subsumed by the camera. Neide Jallageas proposes the study of visual communication design from the first modelings, attempting especially to the radical propositions from the early XXth century avant-garde movement. Gilson Schwartz debates on the impact from the distribution of videogames as hegemonic cultural practice in

  6. 2013 Australasian sky guide

    CERN Document Server

    Lomb, Nick

    2012-01-01

    Compact, easy to use and reliable, this popular guide contains everything you need to know about the southern night sky with monthly star maps, diagrams and details of all the year's exciting celestial events. Wherever you are in Australia or New Zealand, easy calculations allow you to determine when the Sun, Moon and planets will rise and set throughout the year. Also included is information on the latest astronomical findings from space probes and telescopes around the world. The Sky guide has been published annually by the Powerhouse Museum, Sydney, since 1991. It is recommended for photogr

  7. The monthly sky guide

    CERN Document Server

    Ridpath, Ian

    2006-01-01

    In full colour throughout, the seventh edition of Ian Ridpath and Wil Tirion's famous guide to the night sky is fully revised and updated for planet positions and forthcoming eclipses up to the end of the year 2011. The book contains a chapter on the main sights visible in each month of the year, and is an easy-to-use companion to the night sky. It will help you to identify prominent stars, constellations, star clusters, nebulae and galaxies, to watch out for meteor showers, and to follow the movement of the four brightest planets. Most of the sights described are visible to the naked eye and

  8. Use of Meteosat data to produce sky luminance maps

    OpenAIRE

    Ineichen, Pierre

    1996-01-01

    The objective of the subtask is to derive a model to evaluate the luminance distribution of the sky vault on the basis of Meteosat data. This information is a key element in the field of building energy saving, it is the basis of indoor daylight calculation. Evaluation programs like Genelux (LASH-ENTPE) need this sky luminance distribution to perform their calculations. Sky luminance distribution models have been developed in the last years on the basis of horizontal diffuse illuminance. Thei...

  9. Characterizing Sky Spectra Using SDSS BOSS Data

    Science.gov (United States)

    Florez, Lina Maria; Strauss, Michael A.

    2018-01-01

    In the optical/near-infrared spectra gathered by a ground-based telescope observing very faint sources, the strengths of the emission lines due to the Earth’s atmosphere can be many times larger than the fluxes of the sources we are interested in. Thus the limiting factor in faint-object spectroscopy is the degree to which systematics in the sky subtraction can be minimized. Longwards of 6000 Angstroms, the night-sky spectrum is dominated by multiple vibrational/rotational transitions of the OH radical from our upper atmosphere. While the wavelengths of these lines are the same in each sky spectrum, their relative strengths vary considerably as a function of time and position on the sky. The better we can model their strengths, the better we can hope to subtract them off. We expect that the strength of lines from common upper energy levels will be correlated with one another. We used flux-calibrated sky spectra from the Sloan Digital Sky Survey Baryon Oscillation Spectroscopic Survey (SDSS BOSS) to explore these correlations. Our aim is to use these correlations for creating improved sky subtraction algorithms for the Prime Focus Spectrograph (PFS) on the 8.2-meter Subaru Telescope. When PFS starts gathering data in 2019, it will be the most powerful multi-object spectrograph in the world. Since PFS will be gathering data on sources as faint as 24th magnitude and fainter, it's of upmost importance to be able to accurately measure and subtract sky spectra from the data that we receive.

  10. Calibration of an all-sky camera for obtaining sky radiance at three wavelengths

    Directory of Open Access Journals (Sweden)

    R. Román

    2012-08-01

    Full Text Available This paper proposes a method to obtain spectral sky radiances, at three wavelengths (464, 534 and 626 nm, from hemispherical sky images. Images are registered with the All-Sky Imager installed at the Andalusian Center for Environmental Research (CEAMA in Granada (Spain. The methodology followed in this work for the absolute calibration in radiance of this instrument is based on the comparison of its output measurements with modelled sky radiances derived from the LibRadtran/UVSPEC radiative transfer code under cloud-free conditions. Previously, in order to check the goodness of the simulated radiances, these are compared with experimental values recorded by a CIMEL sunphotometer. In general, modelled radiances are in agreement with experimental data, showing mean differences lower than 20% except for the pixels located next to the Sun position that show larger errors.

    The relationship between the output signal of the All-Sky Imager and the modelled sky radiances provides a calibration matrix for each image. The variability of the matrix coefficients is analyzed, showing no significant changes along a period of 5 months. Therefore, a unique calibration matrix per channel is obtained for all selected images (a total of 705 images per channel. Camera radiances are compared with CIMEL radiances, finding mean absolute differences between 2% and 15% except for pixels near to the Sun and high scattering angles. We apply these calibration matrices to three images in order to study the sky radiance distributions for three different sky conditions: cloudless, overcast and partially cloudy. Horizon brightening under cloudless conditions has been observed together with the enhancement effect of individual clouds on sky radiance.

  11. The observer's sky atlas

    CERN Document Server

    Karkoschka, E

    2007-01-01

    This title includes a short introduction to observing, a thorough description of the star charts and tables, a glossary and much more. It is perfect for both the beginner and seasoned observer. It is fully revised edition of a best-selling and highly-praised sky atlas.

  12. The Big Sky inside

    Science.gov (United States)

    Adams, Earle; Ward, Tony J.; Vanek, Diana; Marra, Nancy; Hester, Carolyn; Knuth, Randy; Spangler, Todd; Jones, David; Henthorn, Melissa; Hammill, Brock; Smith, Paul; Salisbury, Rob; Reckin, Gene; Boulafentis, Johna

    2009-01-01

    The University of Montana (UM)-Missoula has implemented a problem-based program in which students perform scientific research focused on indoor air pollution. The Air Toxics Under the Big Sky program (Jones et al. 2007; Adams et al. 2008; Ward et al. 2008) provides a community-based framework for understanding the complex relationship between poor…

  13. On the relation between zenith sky brightness and horizontal illuminance

    Science.gov (United States)

    Kocifaj, M.; Posch, Th.; Solano Lamphar, H. A.

    2015-01-01

    The effects of artificial light at night are an emergent research topic for astronomers, physicists, engineers and biologists around the world. This leads to a need for measurements of the night sky brightness (= diffuse luminance of the night sky) and nocturnal illuminance. Currently, the most sensitive light meters measure the zenith sky brightness in magV/arcsec2 or - less frequently - in cd m-2. However, the horizontal illuminance resulting only from the night sky is an important source of information that is difficult to obtain with common instruments. Here we present a set of approximations to convert the zenith luminance into horizontal illuminance. Three different approximations are presented for three idealized atmospheric conditions: homogeneous sky brightness, an isotropically scattering atmosphere and a turbid atmosphere. We also apply the resulting conversion formulae to experimental data on night sky luminance, obtained during the past three years.

  14. Dark Skies: Local Success, Global Challenge

    Science.gov (United States)

    Lockwood, G. W.

    2009-01-01

    The Flagstaff, Arizona 1987 lighting code reduced the growth rate of man-made sky glow by a third. Components of the code include requirements for full cutoff lighting, lumens per acre limits in radial zones around observatories, and use of low-pressure sodium monochromatic lighting for roadways and parking lots. Broad public acceptance of Flagstaff's lighting code demonstrates that dark sky preservation has significant appeal and few visibility or public safety negatives. An inventory by C. Luginbuhl et al. of the light output and shielding of a sampling of various zoning categories (municipal, commercial, apartments, single-family residences, roadways, sports facilities, industrial, etc.), extrapolated over the entire city, yields a total output of 139 million lumens. Commercial and industrial sources account for 62% of the total. Outdoor sports lighting increases the total by 24% on summer evenings. Flagstaff's per capita lumen output is 2.5 times greater than the nominal 1,000 lumens per capita assumed by R. Garstang in his early sky glow modeling work. We resolved the discrepancy with respect to Flagstaff's measured sky glow using an improved model that includes substantial near ground attenuation by foliage and structures. A 2008 university study shows that astronomy contributes $250M annually to Arizona's economy. Another study showed that the application of lighting codes throughout Arizona could reduce energy consumption significantly. An ongoing effort led by observatory directors statewide will encourage lighting controls in currently unregulated metropolitan areas whose growing sky glow threatens observatory facilities more than 100 miles away. The national press (New York Times, the New Yorker, the Economist, USA Today, etc.) have publicized dark sky issues but frequent repetition of the essential message and vigorous action will be required to steer society toward darker skies and less egregious waste.

  15. Building models for marketing decisions : Past, present and future

    NARCIS (Netherlands)

    Leeflang, PSH; Wittink, DR

    We review five eras of model building in marketing, with special emphasis on the fourth and the fifth eras, the present and the future. At many firms managers now routinely use model-based results for marketing decisions. Given an increasing number of successful applications, the demand for models

  16. Building models for marketing decisions : past, present and future

    NARCIS (Netherlands)

    Leeflang, P.S.H.; Wittink, Dick R.

    2000-01-01

    We review five eras of model building in marketing, with special emphasis on the fourth and the fifth eras, the present and the future. At many firms managers now routinely use model-based results for marketing decisions. Given an increasing number of successful applications, the demand for models

  17. Recovering alternative presentation models of a web page with VAQUITA

    OpenAIRE

    Bouillon, Laurent; Vanderdonckt, Jean; Souchon, Nathalie

    2002-01-01

    VAQUITA allows developers to reverse engineer a presentation model of a web page according to multiple reverse engineering options. The alternative models offered by these options not only widen the spectrum of possible presentation models but also encourage developers in exploring multiple reverse engineering strategies. The options provide filtering capabilities in a static analysis of HTML code that are targeted either at multiple widgets simultaneously or at single widgets ...

  18. Infrared Sky Surveys

    Science.gov (United States)

    Price, Stephan D.

    2009-02-01

    A retrospective is given on infrared sky surveys from Thomas Edison’s proposal in the late 1870s to IRAS, the first sensitive mid- to far-infrared all-sky survey, and the mid-1990s experiments that filled in the IRAS deficiencies. The emerging technology for space-based surveys is highlighted, as is the prominent role the US Defense Department, particularly the Air Force, played in developing and applying detector and cryogenic sensor advances to early mid-infrared probe-rocket and satellite-based surveys. This technology was transitioned to the infrared astronomical community in relatively short order and was essential to the success of IRAS, COBE and ISO. Mention is made of several of the little known early observational programs that were superseded by more successful efforts.

  19. The VLA Sky Survey

    Science.gov (United States)

    Lacy, Mark; VLASS Survey Team, VLASS Survey Science Group

    2018-01-01

    The VLA Sky Survey (VLASS), which began in September 2017, is a seven year project to image the entire sky north of Declination -40 degrees in three epochs. The survey is being carried out in I,Q and U polarization at a frequency of 2-4GHz, and a resolution of 2.5 arcseconds, with each epoch being separated by 32 months. Raw data from the survey, along with basic "quicklook" images are made freely available shortly after observation. Within a few months, NRAO will begin making available further basic data products, including refined images and source lists. In this talk I shall describe the science goals and methodology of the survey, the current survey status, and some early results, along with plans for collaborations with external groups to produce enhanced, high level data products.

  20. Simplified Night Sky Display System

    Science.gov (United States)

    Castellano, Timothy P.

    2010-01-01

    A document describes a simple night sky display system that is portable, lightweight, and includes, at most, four components in its simplest configuration. The total volume of this system is no more than 10(sup 6) cm(sup 3) in a disassembled state, and weighs no more than 20 kilograms. The four basic components are a computer, a projector, a spherical light-reflecting first surface and mount, and a spherical second surface for display. The computer has temporary or permanent memory that contains at least one signal representing one or more images of a portion of the sky when viewed from an arbitrary position, and at a selected time. The first surface reflector is spherical and receives and reflects the image from the projector onto the second surface, which is shaped like a hemisphere. This system may be used to simulate selected portions of the night sky, preserving the appearance and kinesthetic sense of the celestial sphere surrounding the Earth or any other point in space. These points will then show motions of planets, stars, galaxies, nebulae, and comets that are visible from that position. The images may be motionless, or move with the passage of time. The array of images presented, and vantage points in space, are limited only by the computer software that is available, or can be developed. An optional approach is to have the screen (second surface) self-inflate by means of gas within the enclosed volume, and then self-regulate that gas in order to support itself without any other mechanical support.

  1. An Innovative Collaboration on Dark Skies Education

    Science.gov (United States)

    Walker, Constance E.; Mayer, M.; EPO Students, NOAO

    2011-01-01

    Dark night skies are being lost all over the globe, and hundreds of millions of dollars of energy are being wasted in the process.. Improper lighting is the main cause of light pollution. Light pollution is a concern on many fronts, affecting safety, energy conservation, cost, human health, and wildlife. It also robs us of the beauty of viewing the night sky. In the U.S. alone, over half of the population cannot see the Milky Way from where they live. To help address this, the National Optical Astronomy Observatory Education and Public Outreach (NOAO EPO) staff created two programs: Dark Skies Rangers and GLOBE at Night. Through the two programs, students learn about the importance of dark skies and experience activities that illustrate proper lighting, light pollution's effects on wildlife and how to measure the darkness of their skies. To disseminate the programs locally in an appropriate yet innovative venue, NOAO partnered with the Cooper Center for Environmental Learning in Tucson, Arizona. Operated by the largest school district in Tucson and the University of Arizona College of Education, the Cooper Center educates thousands of students and educators each year about ecology, science, and the beauty and wonders of the Sonoran Desert. During the first academic year (2009-2010), we achieved our goal of reaching nearly 20 teachers in 40 classrooms of 1000 students. We gave two 3-hour teacher-training sessions and provided nineteen 2.5-hour on-site evening sessions on dark skies activities for the students of the teachers trained. One outcome of the program was the contribution of 1000 "GLOBE at Night 2010” night-sky brightness measurements by Tucson students. Training sessions at similar levels are continuing this year. The partnership, planning, lesson learned, and outcomes of NOAO's collaboration with the environmental center will be presented.

  2. Sensitivity of clear-sky direct radiative effect of the aerosol to micro-physical properties by using 6SV radiative transfer model: preliminary results

    Science.gov (United States)

    Bassani, Cristiana; Tirelli, Cecilia; Manzo, Ciro; Pietrodangelo, Adriana; Curci, Gabriele

    2015-04-01

    The aerosol micro-physical properties are crucial to analyze their radiative impact on the Earth's radiation budget [IPCC, 2007]. The 6SV model, last generation of the Second Simulation of a Satellite Signal in the Solar Spectrum (6S) radiative transfer code [Kotchenova et al., 2007; Vermote et al., 1997] has been used to perform physically-based atmospheric correction of hyperspectral airborne and aircraft remote sensing data [Vermote et al., 2009; Bassani et al. 2010; Tirelli et al., 2014]. The atmospheric correction of hyperspectral data has been shown to be sensitive to the aerosol micro-physical properties, as reported in Bassani et al., 2012. The role of the aerosol micro-physical properties on the accuracy of the atmospheric correction of hyperspectral data acquired over water and land targets is investigated within the framework of CLAM-PHYM (Coasts and Lake Assessment and Monitoring by PRISMA HYperspectral Mission) and PRIMES (Synergistic use of PRISMA products with high resolution meteo-chemical simulations and their validation on ground and from satellite) projects, both funded by Italian Space Agency (ASI). In this work, the results of the radiative field of the Earth/Atmosphere coupled system simulated by using 6SV during the atmospheric correction of hyperspectral data are presented. The analysis of the clear-sky direct radiative effect is performed considering the aerosol micro-physical properties used to define the aerosol model during the atmospheric correction process. In particular, the AERONET [Holben et al., 1998] and FLEXAOD [Curci et al., 2014] micro-physical properties are used for each image to evaluate the contribution of the size distribution and refractive index of the aerosol type on the surface reflectance and on the direct radiative forcing. The results highlight the potential of the hyperspectral remote sensing data for atmospheric studies as well as for environmental studies. Currently, the future hyperspectral missions, such as the

  3. Comparison of the observed and calculated clear sky greenhouse effect - Implications for climate studies

    Science.gov (United States)

    Kiehl, J. T.; Briegleb, B. P.

    1992-01-01

    The clear sky greenhouse effect is defined in terms of the outgoing longwave clear sky flux at the top of the atmosphere. Recently, interest in the magnitude of the clear sky greenhouse effect has increased due to the archiving of the clear sky flux quantity through the Earth Radiation Budget Experiment (ERBE). The present study investigates to what degree of accuracy this flux can be analyzed by using independent atmospheric and surface data in conjunction with a detailed longwave radiation model. The conclusion from this comparison is that for most regions over oceans the analyzed fluxes agree to within the accuracy of the ERBE-retrieved fluxes (+/- 5 W/sq m). However, in regions where deep convective activity occurs, the ERBE fluxes are significantly higher (10-15 W/sq m) than the calculated fluxes. This bias can arise from either cloud contamination problems or variability in water vapor amount. It is argued that the use of analyzed fluxes may provide a more consistent clear sky flux data set for general circulation modeling validation. Climate implications from the analyzed fluxes are explored. Finally, results for obtaining longwave surface fluxes over the oceans are presented.

  4. Presenting Cultural Heritage Landscapes - from GIS via 3d Models to Interactive Presentation Frameworks

    Science.gov (United States)

    Prechtel, N.; Münster, S.; Kröber, C.; Schubert, C.; Schietzold, S.

    2013-07-01

    Two current projects of the authors try to approach cultural heritage landscapes from both cultural sciences and geography through a combination of customised geo-information (GIS) and visualisation/presentation technology. In excess of a mere academic use, easyto- handle virtual 3D web presentations may contribute to knowledge, esteem, commemoration and preservation. The examples relate to pre-historic Scythian burial sites in the South-Siberian Altay Mountains ("Uch Enmek") as well as to a "virtual memorial" of contemporary history ("GEPAM"), a chapter of Jewish prosecution in the "Third Reich", which historically connects the town of Dresden with the Czech Terezin (Theresienstadt). It is common knowledge that a profound understanding of (pre-)historic artefacts and places may reflect a larger environment as well as an individual geographic setting. Coming from this background, the presented projects try to find technical solutions. They start from GIS models and aim at customised interactive presentations of 3D models. In using the latter a widely-spanned public is invited to a land- or townscape of specific cultural importance. The geographic space is thought to work as a door to a repository of educational exhibits under the umbrella of a web application. Within this concept a landscape/townscape also accounts for the time dimension in different scales (time of construction/operation versus actual state, and in sense of a season and time of the day as a principal modulator of visual perception of space).

  5. The sky as a topic in science education

    Science.gov (United States)

    Galili, Igal; Weizman, Ayelet; Cohen, Ariel

    2004-07-01

    The concepts of sky and visibility distance, as perceived by different learners, are investigated for the first time as a subject of a science education research. Mental models of students with regard to the subject were elicited. They were interpreted in terms of two-level hierarchy: schemes and facets-of-knowledge (defined in the paper). Our results suggest that many students do not consider sky to be a scientific (physical) concept. The majority perceives the sky as having an oblate profile. Among the parameters that determine this profile were mentioned daytime, atmosphere, geometry of the situation, and weather conditions. The students hold two major explanatory views (schemes) with regard to the sky: the sky is the atmosphere and the sky is the appearance of space. With regard to the visibility distance, the two following schemes prevail: vision weakens with the distance and natural obstacles determine vision distance. No significant correlation was found between the views regarding the sky appearance and the vision distance. Students do not relate Moon illusion to the profile of sky or visibility distance. The notions of sky and visibility distance are argued for inclusion into science curriculum, and implications of the findings to a constructivist instruction of the considered concepts and phenomena are discussed.

  6. Why Is the Sky Dark at Night?

    Science.gov (United States)

    Stinner, Arthur

    2014-01-01

    The puzzle as to just why the sky is dark at night, given that there are so many stars, has been around at least since Newton. This article summarizes six cosmological models that have been used to attempt to give an account of this puzzle including the Copernican universe, the Newton-Halley universe, the nineteenth century "one galaxy"…

  7. Gender Roles and Night-Sky Watching among College Students

    Science.gov (United States)

    Kelly, William E.; McGee, Catherine M.

    2012-01-01

    The present study investigated the relationship between gender roles and night-sky watching in a sample of college students (N=161). The Bem Sex-Role Inventory (BSRI) and the Noctcaelador Inventory (NI) were used to investigate the differences between gender role groups for night-sky watching. The results supported the hypothesis that androgynous…

  8. Light pollution: Assessment of sky glow on two dark sky regions of Portugal.

    Science.gov (United States)

    Lima, Raul Cerveira; Pinto da Cunha, José; Peixinho, Nuno

    2016-01-01

    Artificial light at night (ALAN), producing light pollution (LP), is not a matter restricted to astronomy anymore. Light is part of modern societies and, as a consequence, the natural cycle day-night (bright-dark) has been interrupted in a large segment of the global population. There is increasing evidence that exposure to certain types of light at night and beyond threshold levels may produce hazardous effects to humans and the environment. The concept of "dark skies reserves" is a step forward in order to preserve the night sky and a means of enhancing public awareness of the problem of spread of light pollution worldwide. The aim of this study was to assess the skyglow at two sites in Portugal, the Peneda-Gerês National Park (PNPG) and the region now known as Dark Sky Alqueva Reserve. The latter site was classified as a "Starlight Tourism Destination" by the Starlight Foundation (the first in the world to achieve this classification) following a series of night sky measurements in situ described herein. The measurements at PNPG also contributed to the new set of regulations concerning light pollution at this national park. This study presents the first in situ systematic measurements of night sky brightness, showing that at the two sites the skies are mostly in levels 3 to 4 of the Bortle 9-level scale (with level 1 being the best achievable). The results indicate that the sources of light pollution and skyglow can be attributed predominantly to contamination from nearby urban regions.

  9. The Rainbow Sky

    CERN Document Server

    Buick, Tony

    2010-01-01

    The world is full of color, from the blue ocean and the yellow daffodils and sunflowers in green carpeted meadows to the majestic purple mountains in the distance and brightly hued coral reefs off the edges of tropical coasts. But what is color, exactly? Why do we see things in different colors? Do we all see the same colors? Like the surface of our planet, the sky above us offers us an endless palette of color, a visual feast for the eyes. Besides atmospheric phenomena such as sunsets and rainbows, there are the many varied worlds of the Solar System, which we can spy through our telescopes, with their subtle colorings of beige and blue and green. Faraway star systems have suns that come in shades ranging from red and yellow to blue and white. Scientists even often use "false colors" to enhance the features of images they take of structures, such as the rings of Saturn and Jupiter’s clouds. This book, with its clear explanations of what makes the sky such a colorful place and in its great wealth of picture...

  10. Sun, Earth and Sky

    CERN Document Server

    Lang, Kenneth R

    2006-01-01

    This Second Edition of Sun, Earth and Sky updates the popular text by providing comprehensive accounts of the most recent discoveries made by five modern solar spacecraft during the past decade. Their instruments have used sound waves to peer deep into the Sun’s inner regions and measure the temperature of its central nuclear reactor, and extended our gaze far from the visible Sun to record energetic outbursts that threaten Earth. Breakthrough observations with the underground Sudbury Neutrino Observatory are also included, which explain the new physics of ghostly neutrinos and solve the problematic mismatch between the predicted and observed amounts of solar neutrinos. This new edition of Sun, Earth and Sky also describes our recent understanding of how the Sun’s outer atmosphere is heated to a million degrees, and just where the Sun’s continuous winds come from. As humans we are more intimately linked with our life-sustaining Sun than with any other astronomical object, and the new edition therefore p...

  11. Presenting an Evaluation Model for the Cancer Registry Software.

    Science.gov (United States)

    Moghaddasi, Hamid; Asadi, Farkhondeh; Rabiei, Reza; Rahimi, Farough; Shahbodaghi, Reihaneh

    2017-12-01

    As cancer is increasingly growing, cancer registry is of great importance as the main core of cancer control programs, and many different software has been designed for this purpose. Therefore, establishing a comprehensive evaluation model is essential to evaluate and compare a wide range of such software. In this study, the criteria of the cancer registry software have been determined by studying the documents and two functional software of this field. The evaluation tool was a checklist and in order to validate the model, this checklist was presented to experts in the form of a questionnaire. To analyze the results of validation, an agreed coefficient of %75 was determined in order to apply changes. Finally, when the model was approved, the final version of the evaluation model for the cancer registry software was presented. The evaluation model of this study contains tool and method of evaluation. The evaluation tool is a checklist including the general and specific criteria of the cancer registry software along with their sub-criteria. The evaluation method of this study was chosen as a criteria-based evaluation method based on the findings. The model of this study encompasses various dimensions of cancer registry software and a proper method for evaluating it. The strong point of this evaluation model is the separation between general criteria and the specific ones, while trying to fulfill the comprehensiveness of the criteria. Since this model has been validated, it can be used as a standard to evaluate the cancer registry software.

  12. Possibilistic Fuzzy Net Present Value Model and Application

    Directory of Open Access Journals (Sweden)

    S. S. Appadoo

    2014-01-01

    Full Text Available The cash flow values and the interest rate in the net present value (NPV model are usually specified by either crisp numbers or random variables. In this paper, we first discuss some of the recent developments in possibility theory and find closed form expressions for fuzzy possibilistic net present value (FNPV. Then, following Carlsson and Fullér (2001, we discuss some of the possibilistic moments related to FNPV model along with an illustrative numerical example. We also give a unified approach to find higher order moments of FNPV by using the moment generating function introduced by Paseka et al. (2011.

  13. Numerical modelling of present and future hydrology at Laxemar- Simpevarp

    Energy Technology Data Exchange (ETDEWEB)

    Sassner, Mona; Sabel, Ulrika (DHI Sverige AB (Sweden)); Bosson, Emma; Berglund, Sten (Svensk Kaernbraenslehantering AB (Sweden))

    2011-04-15

    The Swedish Nuclear Fuel and Waste Management Company (SKB) has performed site investigations at two potential sites for a final repository for spent nuclear fuel. This report presents results of water flow modelling of the Laxemar area. The modelling reported in this document is focused on the near-surface groundwater, i.e. groundwater in Quaternary deposits and shallow rock, and surface water systems, and was performed using the MIKE SHE tool. The main objective of the modelling was to provide input to the radionuclide transport and dose calculations that were carried out as a part of the comparison between the Laxemar and Forsmark sites

  14. Comparison of Predictive Models for PV Module Performance (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Marion, B.

    2008-05-01

    This paper examines three models used to estimate the maximum power (P{sub m}) of PV modules when the irradiance and PV cell temperature are known: (1) the power temperature coefficient model, (2) the PVFORM model, and (3) the bilinear interpolation model. A variation of the power temperature coefficient model is also presented that improved model accuracy. For modeling values of P{sub m}, an 'effective' plane-of-array (POA) irradiance (E{sub e}) and the PV cell temperature (T) are used as model inputs. Using E{sub e} essentially removes the effects of variations in solar spectrum and reflectance losses, and permits the influence of irradiance and temperature on model performance for P{sub m} to be more easily studied. Eq. 1 is used to determine E{sub e} from T and the PV module's measured short-circuit current (I{sub sc}). Zero subscripts denote performance at Standard Reporting Conditions (SRC).

  15. Accounting for the effects of sastrugi in the CERES clear-sky Antarctic shortwave angular distribution models

    OpenAIRE

    Corbett, J.; Su, W.

    2015-01-01

    The Cloud and the Earth's Radiant Energy System (CERES) instruments on NASA's Terra, Aqua and Soumi NPP satellites are used to provide a long-term measurement of Earth's energy budget. To accomplish this, the radiances measured by the instruments must be inverted to fluxes by the use of a scene-type-dependent angular distribution model (ADM). For permanent snow scenes over Antarctica, shortwave (SW) ADMs are created by compositing radiance measurements over the full viewin...

  16. Advances in Modeling Eclipsing Binary Stars in the Era of Large All-Sky Surveys with EBAI and PHOEBE

    Science.gov (United States)

    Prša, A.; Guinan, E. F.; Devinney, E. J.; Degroote, P.; Bloemen, S.; Matijevič, G.

    2012-04-01

    With the launch of NASA's Kepler mission, stellar astrophysics in general, and the eclipsing binary star field in particular, has witnessed a surge in data quality, interpretation possibilities, and the ability to confront theoretical predictions with observations. The unprecedented data accuracy and an essentially uninterrupted observing mode of over 2000 eclipsing binaries is revolutionizing the field. Amidst all this excitement, we came to realize that our best models to describe the physical and geometric properties of binaries are not good enough. Systematic errors are evident in a large range of binary light curves, and the residuals are anything but Gaussian. This is crucial because it limits us in the precision of the attained parameters. Since eclipsing binary stars are prime targets for determining the fundamental properties of stars, including their ages and distances, the penalty for this loss of accuracy affects other areas of astrophysics as well. Here, we propose to substantially revamp our current models by applying the lessons learned while reducing, modeling, and analyzing Kepler data.

  17. Macro-System Model Project #AN011 (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, M. F.; Diakov, V.; Sa, T. J.; Goldsby, M.

    2010-06-08

    A review of the Macro-System Model for hydrogen production pathways analysis, including objectives, accomplishments, collaborations, and future work. Presented at the 2010 U.S. Department of Energy Hydrogen Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting, June 7-11, 2010, in Washington, DC.

  18. The new World Atlas of Artificial Sky Brightness

    Science.gov (United States)

    Falchi, Fabio; Cinzano, Pierantonio; Kyba, Christopher C. M.; Portnov, Boris A.

    2015-08-01

    I present the main steps toward the completion of the new World Atlas of Artificial Sky Brightness (WA II) and some results. The computational technique has been updated, in comparison to the first World Atlas, to take into account both sources and sites elevation. The elevation data are from USGS GTOPO30 global digital elevation model, with the same pixel size as the WA II maps. The upward emission function used to compute the Atlas is a three parameters function. The parameters can be constrained to the database of Earth based night sky brightness measurements. In this way we can use the better fitting upward function for the final map’s calibration. We maintained constant atmosphere parameters over the entire Earth, identical to those used for the first Atlas (Garstang atmospheric clarity coefficient k=1, equivalent to a vertical extinction at sea level of 0.33 magnitude in the V band). This was done in order to avoid introducing a local bias due to different conditions that may confound the light pollution propagation effects. The radiance data used are those from Visible Infrared Imaging Radiometer Suite (VIIRS) Day-Night Band (DNB) on board the Suomi NPP satellite. The use of this newly available radiance data allows for an increased real resolution, even while maintaining the same 30"x30" lat-lon pixel size. Anyway, a higher resolution is really appreciable only in the immediate proximity of sources of light pollution (e.g. inside a big city). The VIIRS DNB data used for the input data were chosen from the months ranging from May to September in order to avoid introducing bias from the variable snow coverage in mid to high northern latitudes. In the southern hemisphere this problem is far less pronounced. The WA II takes advantage of the now enormous database of Earth based sky brightness measurements obtained mainly with Sky Quality Meters, but also with CCD measurements.

  19. The hunt for 100% sky coverage

    Science.gov (United States)

    Meimon, Serge; Fusco, Thierry; Clenet, Yann; Conan, Jean-Marc; Assémat, François; Michau, Vincent

    2010-07-01

    Tomographic AO (or Wide Field AO) systems use LGS to build a 3D model of turbulence, but rely on NGS for low order sensing. .To preserve reasonable sky coverage, each photon coming from the NGS to sense Tip Tilt has to be optimally exploited. That means a smart control law, a low detection noise, a concentration of the photons onto a small patch and a wave front sensor concept with favorable noise propagation. In this paper, we describe the system choices that were made during the E-ELT laser tomographic system ATLAS phase A study, in order to get a sky coverage as close as possible to 100%. A correct estimation of the sky coverage is therefore a key issue. We have developped a sky coverage estimation strategy based on a Besaņcon model starfield generation, a star(s) selection tool, and a careful estimation of the residual anisoplanatism (after reconstruction process between the NGSs), noise and temporal contributors. We describe the details of the procedure, and derive the ATLAS expected performance.

  20. Recent Characterization of the Night-Sky Irradiance in the Visible/Near-Infrared Spectral Band

    Science.gov (United States)

    Moore, Carolynn; Wood, Michael; Bender, Edward; Hart, Steve

    2018-01-01

    The U.S. Army RDECOM CERDEC NVESD has made numerous characterizations of the night sky over the past 45 years. Up until the last four years, the measurement devices were highly detector-limited, which led to low spectral resolution, marginal sensitivity in no-moon conditions, and the need for inferential analysis of the resulting data. In 2014, however, the PhotoResearch Model PR-745 spectro-radiometer established a new state of the art for measurement of the integrated night-sky irradiance over the Visible-to-Near-Infrared (VNIR) spectral band (400-1050nm). This has enabled characterization of no-moon night-sky irradiance with a spectral bandwidth less than 15 nanometers, even when this irradiance is attenuated by heavy clouds or forest canopy. Since 2014, we have conducted a series of night-sky data collections at remote sites across the United States. The resulting data has provided new insights into natural radiance variations, cultural lighting impacts, and the spectrally-varying attenuation caused by cloud cover and forest canopy. Several new metrics have also been developed to provide insight into these newly-found components and temporal variations. The observations, findings and conclusions of the above efforts will be presented, including planned near-term efforts to further characterize the night-sky irradiance in the Visible/Near-Infrared spectral band.

  1. The clear‐sky index to separate clear‐sky from cloudy‐sky situations in climate research

    National Research Council Canada - National Science Library

    Marty, Christoph; Philipona, Rolf

    2000-01-01

    .... A Clear‐Sky Index (CSI) to separate clear‐sky from cloudy‐sky situations has therefore been introduced, using accurate atmospheric longwave radiation in conjunction with air temperature and humidity measurements at the station. This clear...

  2. Predictive Models of Li-ion Battery Lifetime (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G.; Shi, Y.; Pesaran, A.

    2014-09-01

    Predictive models of Li-ion battery reliability must consider a multiplicity of electrochemical, thermal and mechanical degradation modes experienced by batteries in application environments. Complicating matters, Li-ion batteries can experience several path dependent degradation trajectories dependent on storage and cycling history of the application environment. Rates of degradation are controlled by factors such as temperature history, electrochemical operating window, and charge/discharge rate. Lacking accurate models and tests, lifetime uncertainty must be absorbed by overdesign and warranty costs. Degradation models are needed that predict lifetime more accurately and with less test data. Models should also provide engineering feedback for next generation battery designs. This presentation reviews both multi-dimensional physical models and simpler, lumped surrogate models of battery electrochemical and mechanical degradation. Models are compared with cell- and pack-level aging data from commercial Li-ion chemistries. The analysis elucidates the relative importance of electrochemical and mechanical stress-induced degradation mechanisms in real-world operating environments. Opportunities for extending the lifetime of commercial battery systems are explored.

  3. RECONSTRUCTION OF SKY ILLUMINATION DOMES FROM GROUND-BASED PANORAMAS

    Directory of Open Access Journals (Sweden)

    F. Coubard

    2012-07-01

    Full Text Available The knowledge of the sky illumination is important for radiometric corrections and for computer graphics applications such as relighting or augmented reality. We propose an approach to compute environment maps, representing the sky radiance, from a set of ground-based images acquired by a panoramic acquisition system, for instance a mobile-mapping system. These images can be affected by important radiometric artifacts, such as bloom or overexposure. A Perez radiance model is estimated with the blue sky pixels of the images, and used to compute additive corrections in order to reduce these radiometric artifacts. The sky pixels are then aggregated in an environment map, which still suffers from discontinuities on stitching edges. The influence of the quality of estimated sky radiance on the simulated light signal is measured quantitatively on a simple synthetic urban scene; in our case, the maximal error for the total sensor radiance is about 10%.

  4. Nuclear model developments in FLUKA for present and future applications

    Directory of Open Access Journals (Sweden)

    Cerutti Francesco

    2017-01-01

    Full Text Available The FLUKAS code [1–3] is used in research laboratories all around the world for challenging applications spanning a very wide range of energies, projectiles and targets. FLUKAS is also extensively used for in hadrontherapy research studies and clinical planning systems. In this paper some of the recent developments in the FLUKAS nuclear physics models of relevance for very different application fields including medical physics are presented. A few examples are shown demonstrating the effectiveness of the upgraded code.

  5. Nuclear model developments in FLUKA for present and future applications

    Science.gov (United States)

    Cerutti, Francesco; Empl, Anton; Fedynitch, Anatoli; Ferrari, Alfredo; Ruben, GarciaAlia; Sala, Paola R.; Smirnov, George; Vlachoudis, Vasilis

    2017-09-01

    The FLUKAS code [1-3] is used in research laboratories all around the world for challenging applications spanning a very wide range of energies, projectiles and targets. FLUKAS is also extensively used for in hadrontherapy research studies and clinical planning systems. In this paper some of the recent developments in the FLUKAS nuclear physics models of relevance for very different application fields including medical physics are presented. A few examples are shown demonstrating the effectiveness of the upgraded code.

  6. Present-day heat flow model of Mars

    Science.gov (United States)

    Parro, Laura M.; Jiménez-Díaz, Alberto; Mansilla, Federico; Ruiz, Javier

    2017-04-01

    Until the acquisition of in-situ measurements, the study of the present-day heat flow of Mars must rely on indirect methods, mainly based on the relation between the thermal state of the lithosphere and its mechanical strength, or on theoretical models of internal evolution. Here, we present a first-order global model for the present-day surface heat flow for Mars, based on the radiogenic heat production of the crust and mantle, on scaling of heat flow variations arising from crustal thickness and topography variations, and on the heat flow derived from the effective elastic thickness of the lithosphere beneath the North Polar Region. Our preferred model finds heat flows varying between 14 and 25 mW m-2, with an average value of 19 mW m-2. Similar results (although about ten percent higher) are obtained if we use heat flow based on the lithospheric strength of the South Polar Region. Moreover, expressing our results in terms of the Urey ratio (the ratio between total internal heat production and total heat loss through the surface), we estimate values close to 0.7-0.75, which indicates a moderate contribution of secular cooling to the heat flow of Mars (consistent with the low heat flow values deduced from lithosphere strength), unless heat-producing elements abundances for Mars are subchondritic.

  7. Euroconference on the appropriate modellings of galaxy evolution from their cosmological formation to their presently observable structures

    CERN Document Server

    Stasińska, Grażyna; Harfst, Stefan; Kroupa, Pavel; Theis, Christian; THE EVOLUTION OF GALAXIES

    2003-01-01

    Galaxies have a history This has become clear from recent sky surveys which have shown that distant galaxies, formed early in the life of the Universe, differ from the nearby ones New observational windows at ultraviolet, infrared and millimetric wavelengths (provided by ROSAT, IRAM, IUE, IRAS, ISO) have revealed that galaxies contain a wealth of components very hot gas, atomic hydrogen, molecules, dust, dark matter A significant advance is expected from the results of new instruments (VLT, FIRST, XMM) which will allow one to explore the most distant Universe Three Euroconferences were planned to punctuate this new epoch in galactic research, bringing together specialists in various fields of Astronomy This book contains the proceedings of the third conference and presents the actual state-of-the-art of modelling galaxy evolution

  8. Anthropogenic changes in the surface all-sky UV-B radiation through 1850–2005 simulated by an Earth system model

    Directory of Open Access Journals (Sweden)

    S. Watanabe

    2012-06-01

    Full Text Available The historical anthropogenic change in the surface all-sky UV-B (solar ultraviolet: 280–315 nm radiation through 1850–2005 is evaluated using an Earth system model. Responses of UV-B dose to anthropogenic changes in ozone and aerosols are separately evaluated using a series of historical simulations including/excluding these changes. Increases in these air pollutants cause reductions in UV-B transmittance, which occur gradually/rapidly before/after 1950 in and downwind of industrial and deforestation regions. Furthermore, changes in ozone transport in the lower stratosphere, which is induced by increasing greenhouse gas concentrations, increase ozone concentration in the extratropical upper troposphere and lower stratosphere. These transient changes work to decrease the amount of UV-B reaching the Earth's surface, counteracting the well-known effect increasing UV-B due to stratospheric ozone depletion, which developed rapidly after ca. 1980. As a consequence, the surface UV-B radiation change between 1850 and 2000 is negative in the tropics and NH extratropics and positive in the SH extratropics. Comparing the contributions of ozone and aerosol changes to the UV-B change, the transient change in ozone absorption of UV-B mainly determines the total change in the surface UV-B radiation at most locations. On the other hand, the aerosol direct and indirect effects on UV-B play an equally important role to that of ozone in the NH mid-latitudes and tropics. A typical example is East Asia (25° N–60° N and 120° E–150° E, where the effect of aerosols (ca. 70% dominates the total UV-B change.

  9. Using cluster analysis and a classification and regression tree model to developed cover types in the Sky Islands of southeastern Arizona

    Science.gov (United States)

    Jose M. Iniguez; Joseph L. Ganey; Peter J. Daughtery; John D. Bailey

    2005-01-01

    The objective of this study was to develop a rule based cover type classification system for the forest and woodland vegetation in the Sky Islands of southeastern Arizona. In order to develop such a system we qualitatively and quantitatively compared a hierarchical (Ward’s) and a non-hierarchical (k-means) clustering method. Ecologically, unique groups represented by...

  10. Using cluster analysis and a classification and regression tree model to developed cover types in the Sky Islands of southeastern Arizona [Abstract

    Science.gov (United States)

    Jose M. Iniguez; Joseph L. Ganey; Peter J. Daugherty; John D. Bailey

    2005-01-01

    The objective of this study was to develop a rule based cover type classification system for the forest and woodland vegetation in the Sky Islands of southeastern Arizona. In order to develop such system we qualitatively and quantitatively compared a hierarchical (Ward’s) and a non-hierarchical (k-means) clustering method. Ecologically, unique groups and plots...

  11. Promoting Landspace Astrophotography for Dark Sky Preservation in Nepal

    Science.gov (United States)

    Dwa, Manisha; Bhattarai, Suresh

    2015-08-01

    This paper will present astrophotography and dark sky preservation initiatives and its impact in Nepal. It will highlight the astrophotography and the dark skies Initiatives of Nepal Astronomical Society (NASO) since 2007. Some case studies from the landspace astrophotography by TWAN, EurAstro Mission and others promoted by NASO will be discussed in details. It will also present our collaborative approach with the media to take the idea of dark sky peservation to Nepalese Community in the country and abroad. Some success stories linked with UNESCO World Heritage Sites of Nepal will be discussed in brief. Our appreach of introducing such photography as a tool for astronomy communication will be discussed.

  12. Exploring the Variable Sky with the Sloan Digital Sky Survey

    Science.gov (United States)

    2007-12-01

    2004) monitors 700 deg2 of sky from V ¼ 13:5 to a limit of V ¼ 21. 3. ROTSE-I ( Akerlof et al. 2000) monitors the entire ob- servable sky twice a...Washington. REFERENCES Adelman-McCarthy, J. K., et al. 2007, ApJS, 172, in press Akerlof , C., et al. 2000, AJ, 119, 1901 Alcock, C., et al. 2001, ApJS, 136

  13. Modeling population exposures to silver nanoparticles present in consumer products

    Science.gov (United States)

    Royce, Steven G.; Mukherjee, Dwaipayan; Cai, Ting; Xu, Shu S.; Alexander, Jocelyn A.; Mi, Zhongyuan; Calderon, Leonardo; Mainelis, Gediminas; Lee, KiBum; Lioy, Paul J.; Tetley, Teresa D.; Chung, Kian Fan; Zhang, Junfeng; Georgopoulos, Panos G.

    2014-11-01

    Exposures of the general population to manufactured nanoparticles (MNPs) are expected to keep rising due to increasing use of MNPs in common consumer products (PEN 2014). The present study focuses on characterizing ambient and indoor population exposures to silver MNPs (nAg). For situations where detailed, case-specific exposure-related data are not available, as in the present study, a novel tiered modeling system, Prioritization/Ranking of Toxic Exposures with GIS (geographic information system) Extension (PRoTEGE), has been developed: it employs a product life cycle analysis (LCA) approach coupled with basic human life stage analysis (LSA) to characterize potential exposures to chemicals of current and emerging concern. The PRoTEGE system has been implemented for ambient and indoor environments, utilizing available MNP production, usage, and properties databases, along with laboratory measurements of potential personal exposures from consumer spray products containing nAg. Modeling of environmental and microenvironmental levels of MNPs employs probabilistic material flow analysis combined with product LCA to account for releases during manufacturing, transport, usage, disposal, etc. Human exposure and dose characterization further employ screening microenvironmental modeling and intake fraction methods combined with LSA for potentially exposed populations, to assess differences associated with gender, age, and demographics. Population distributions of intakes, estimated using the PRoTEGE framework, are consistent with published individual-based intake estimates, demonstrating that PRoTEGE is capable of capturing realistic exposure scenarios for the US population. Distributions of intakes are also used to calculate biologically relevant population distributions of uptakes and target tissue doses through human airway dosimetry modeling that takes into account product MNP size distributions and age-relevant physiological parameters.

  14. Sky Mining - Application to Photomorphic Redshift Estimation

    Science.gov (United States)

    Nayak, Pragyansmita

    severity every day, alternative method "Photometric redshift" has been studied in the past. It uses the brightness of the object viewed through various standard filters, each of which lets through a relatively broad spectrum of colors. However, these methods are bound by the degeneracy problem (objects with different color profiles have the same redshift) which leads to low predictive accuracy. As part of our study, we are looking beyond color attributes to identify other measured attributes as degeneracy resolvers as well as generate estimators that are highly accurate; termed as "Photomorphic redshift" estimators. The present study investigates the photometric information of the objects such as color and magnitude (= observed flux) and morphology attributes such as shape, size, orientation and concentration in the different wavelengths. The specific type of magnitude used in this study are the PSF, Fiber and Petrosian magnitude. The morphology attributes are the ratio of Fiber to Petrosian magnitude, concentration index and Petrosian radius. All these attributes are in the five bands ugriz of the Sloan Digital Sky Survey (SDSS). Machine learning techniques based on Naive Bayes (NB), Bayesian Network (BN) and Generalized Linear Model (GLM) are researched to better understand their applicability, advantages and resulting predictive performance in terms of efficiency and accuracy. Note: The SDSS Data Release (DR) 10 data was used in the executed experiments (total of 700,777 galaxies with forty-five attributes associated with each galaxy). The significant findings of the present work are as follows: 1. Magnitude and morphology attributes have been found to be successful degeneracy resolvers. 2. Magnitude and morphology attributes have been found to be better redshift estimators than color attributes alone. 3. Naive Bayes, Bayesian Network and GLM have been found to be viable redshift estimation methods. Attribute selection is an important factor in computational performance

  15. Digital all-sky polarization imaging of partly cloudy skies.

    Science.gov (United States)

    Pust, Nathan J; Shaw, Joseph A

    2008-12-01

    Clouds reduce the degree of linear polarization (DOLP) of skylight relative to that of a clear sky. Even thin subvisual clouds in the "twilight zone" between clouds and aerosols produce a drop in skylight DOLP long before clouds become visible in the sky. In contrast, the angle of polarization (AOP) of light scattered by a cloud in a partly cloudy sky remains the same as in the clear sky for most cases. In unique instances, though, select clouds display AOP signatures that are oriented 90 degrees from the clear-sky AOP. For these clouds, scattered light oriented parallel to the scattering plane dominates the perpendicularly polarized Rayleigh-scattered light between the instrument and the cloud. For liquid clouds, this effect may assist cloud particle size identification because it occurs only over a relatively limited range of particle radii that will scatter parallel polarized light. Images are shown from a digital all-sky-polarization imager to illustrate these effects. Images are also shown that provide validation of previously published theories for weak (approximately 2%) polarization parallel to the scattering plane for a 22 degrees halo.

  16. SkyGlowNet as a Vehicle for STEM Education

    Science.gov (United States)

    Flurchick, K. M.; Craine, E. R.; Culver, R. B.; Deal, S.; Foster, C.

    2013-06-01

    SkyGlowNet is an emerging network of internet-enabled sky brightness meters (iSBM) that continuously record and log sky brightness at the zenith of each network node site. Also logged are time and weather information. These data are polled at a user-defined frequency, typically about every 45 seconds. The data are uploaded to the SkyGlowNet website, initially to a proprietary area where the data for each institution are embargoed for one or two semesters as students conduct research projects with their data. When released from embargo, the data are moved to another area where they can be accessed by all SkyGlowNet participants. Some of the data are periodically released to a public area on the website. In this presentation we describe the data formats and provide examples of both data content and the structure of the website. Early data from two nodes in the SkyGlowNet have been characterized, both quantitatively and qualitatively, by undergraduate students at NCAT. A summary of their work is presented here. These analyses are of utility in helping those new to looking at these data to understand how to interpret them. In particular, we demonstrate differences between effects on light at night and sky brightness due to astronomical cycles, atmospheric phenomena, and artificial lighting. Quantitative characterization of the data includes statistical analyses of parsed segments of the temporal data stream. An attempt is made to relate statistical metrics to specific types of phenomena.

  17. Uncertainties of parameterized surface downward clear-sky shortwave and all-sky longwave radiation.

    Directory of Open Access Journals (Sweden)

    S. Gubler

    2012-06-01

    Full Text Available As many environmental models rely on simulating the energy balance at the Earth's surface based on parameterized radiative fluxes, knowledge of the inherent model uncertainties is important. In this study we evaluate one parameterization of clear-sky direct, diffuse and global shortwave downward radiation (SDR and diverse parameterizations of clear-sky and all-sky longwave downward radiation (LDR. In a first step, SDR is estimated based on measured input variables and estimated atmospheric parameters for hourly time steps during the years 1996 to 2008. Model behaviour is validated using the high quality measurements of six Alpine Surface Radiation Budget (ASRB stations in Switzerland covering different elevations, and measurements of the Swiss Alpine Climate Radiation Monitoring network (SACRaM in Payerne. In a next step, twelve clear-sky LDR parameterizations are calibrated using the ASRB measurements. One of the best performing parameterizations is elected to estimate all-sky LDR, where cloud transmissivity is estimated using measured and modeled global SDR during daytime. In a last step, the performance of several interpolation methods is evaluated to determine the cloud transmissivity in the night.

    We show that clear-sky direct, diffuse and global SDR is adequately represented by the model when using measurements of the atmospheric parameters precipitable water and aerosol content at Payerne. If the atmospheric parameters are estimated and used as a fix value, the relative mean bias deviance (MBD and the relative root mean squared deviance (RMSD of the clear-sky global SDR scatter between between −2 and 5%, and 7 and 13% within the six locations. The small errors in clear-sky global SDR can be attributed to compensating effects of modeled direct and diffuse SDR since an overestimation of aerosol content in the atmosphere results in underestimating the direct, but overestimating the diffuse SDR. Calibration of LDR parameterizations

  18. Reach the sky

    Science.gov (United States)

    Mariana Peicuti, Cristina

    2017-04-01

    I am working as primary teacher at Scoala Gimnaziala Dumbrava,Timis County, Romania & my pupils has 6 to 10 years old. I was&I am a main pillar in my community, always disseminating knowledge and experience to students, other teachers in the school area &Timis County.Astronomy is the must favorite subject of my students from my classes. They are very courious & always come to me with questions about Earth and Sky because Curriculum scientific disciplines provides too little information about Earth and Sky.I need to know more about how to teach space contents into my classes&what competencies can form in elementary school and also to share my experience to the others.As a result of participation at this meeting I want to attract as many students to astronomy,science/STEM disciplines&space technologies, to astronomy topics and exploration of outer space.Schools needs to be prepared for social life needs,new generations needs,on science/space technologies,which are one of the key points for developing the knowledge society.I intend to introduce new scientific activities as part of the existing curriculum.I am passionate about astronomy,I need to know new approaches and new ideas for primary because I think Science is very important in daily life. Here are some developed activities with pupils from K-2 grade levels wich I wish share with colleagues in Viena. Subject: MATHEMATICS. Primary Topic: MEASUREMENT : -+= ☼ Rockets by Size. Students cut out,color and sequence paper rockets/Read the information on the International Space Station and rockets/Gather pictures of different types of rockets/Print/cut out/color&laminate rocket drawings/Find objects in the room to put in order by height. ☼ Oil Spot Photometer - Measure the brightness of the sun using cooking oil and a white card. A smear of oil on a white card becomes a powerful tool for comparing the brightness of two light sources, including the sun. ☼ The Sundial & Making Shadows-device to measure time by the

  19. Simulations of the Microwave Sky

    Energy Technology Data Exchange (ETDEWEB)

    Sehgal, Neelima; /KIPAC, Menlo Park; Bode, Paul; /Princeton U., Astrophys. Sci. Dept.; Das, Sudeep; /Princeton U., Astrophys. Sci. Dept. /Princeton U.; Hernandez-Monteagudo, Carlos; /Garching, Max Planck Inst.; Huffenberger, Kevin; /Miami U.; Lin, Yen-Ting; /Tokyo U., IPMU; Ostriker, Jeremiah P.; /Princeton U., Astrophys. Sci. Dept.; Trac, Hy; /Harvard-Smithsonian Ctr. Astrophys.

    2009-12-16

    We create realistic, full-sky, half-arcminute resolution simulations of the microwave sky matched to the most recent astrophysical observations. The primary purpose of these simulations is to test the data reduction pipeline for the Atacama Cosmology Telescope (ACT) experiment; however, we have widened the frequency coverage beyond the ACT bands and utilized the easily accessible HEALPix map format to make these simulations applicable to other current and near future microwave background experiments. Some of the novel features of these simulations are that the radio and infrared galaxy populations are correlated with the galaxy cluster and group populations, the primordial microwave background is lensed by the dark matter structure in the simulation via a ray-tracing code, the contribution to the thermal and kinetic Sunyaev-Zel'dovich (SZ) signals from galaxy clusters, groups, and the intergalactic medium has been included, and the gas prescription to model the SZ signals has been refined to match the most recent X-ray observations. The cosmology adopted in these simulations is also consistent with the WMAP 5-year parameter measurements. From these simulations we find a slope for the Y{sub 200} - M{sub 200} relation that is only slightly steeper than self-similar, with an intrinsic scatter in the relation of {approx} 14%. Regarding the contamination of cluster SZ flux by radio galaxies, we find for 148 GHz (90 GHz) only 3% (4%) of halos have their SZ decrements contaminated at a level of 20% or more. We find the contamination levels higher for infrared galaxies. However, at 90 GHz, less than 20% of clusters with M{sub 200} > 2.5 x 10{sup 14}M{sub {circle_dot}} and z < 1.2 have their SZ decrements filled in at a level of 20% or more. At 148 GHz, less than 20% of clusters with M{sub 200} > 2.5 x 10{sup 14}M{sub {circle_dot}} and z < 0.8 have their SZ decrements filled in at a level of 50% or larger. Our models also suggest that a population of very high flux

  20. Armenian Names of Sky Constellations

    Science.gov (United States)

    Mickaelian, A. M.; Farmanyan, S. V.; Mikayelyan, A. A.

    2016-12-01

    The work is devoted to the correction and recovery of the Armenian names of the sky constellations, as they were forgotten or distorted during the Soviet years, mainly due to the translation from Russian. A total of 34 constellation names have been corrected. A brief overview of the history of the division of the sky into constellations and their naming is also given. At the end, the list of all 88 constellations is given with the names in Latin, English, Russian and Armenian.

  1. Treasures of the Southern Sky

    CERN Document Server

    Gendler, Robert; Malin, David

    2011-01-01

    In these pages, the reader can follow the engaging saga of astronomical exploration in the southern hemisphere, in a modern merger of aesthetics, science, and a story of human endeavor. This book is truly a celebration of southern skies.  Jerry Bonnell, Editor - Astronomy Picture of the Day The southern sky became accessible to scientific scrutiny only a few centuries ago, after the first European explorers ventured south of the equator. Modern observing and imaging techniques have since revealed what seems like a new Universe, previously hidden below the horizon, a fresh astronomical bounty of beauty and knowledge uniquely different from the northern sky. The authors have crafted a book that brings this hidden Universe to all, regardless of location or latitude. Treasures of the Southern Sky celebrates the remarkable beauty and richness of the southern sky in words and with world-class imagery. In part, a photographic anthology of deep sky wonders south of the celestial equator, this book also celebrates th...

  2. ESA Sky: a new Astronomy Multi-Mission Interface

    OpenAIRE

    Merín, Bruno; Salgado, Jesús; Giordano, Fabrizio; Baines, Deborah; Sarmiento, María-Henar; Martí, Belén López; Racero, Elena; Gutiérrez, Raúl; Pollock, Andy; Rosa, Michael; Castellanos, Javier; González, Juan,; De león, Ignacio; de Landaluce, Iñaki Ortiz; de Teodoro, Pilar

    2015-01-01

    We present a science-driven discovery portal for all the ESA Astronomy Missions called ESA Sky that allow users to explore the multi-wavelength sky and to seamlessly retrieve science-ready data in all ESA Astronomy mission archives from a web application without prior-knowledge of any of the missions. The first public beta of the service has been released, currently featuring an interface for exploration of the multi-wavelength sky and for single and/or multiple target searches of science-rea...

  3. The Emu Sky Knowledge of the Kamilaroi and Euahlayi Peoples

    CERN Document Server

    Fuller, Robert; Norris, Ray; Trudgett, Michelle

    2014-01-01

    This paper presents a detailed study of the knowledge of the Kamilaroi and Euahlayi peoples about the Emu in the Sky. This study was done with ethnographic data that was not previously reported in detail. We surveyed the literature to find that there are widespread reports of an Emu in the Sky across Australian Aboriginal language groups, but little detailed knowledge available in the literature. This paper reports and describes a comprehensive Kamilaroi and Euahlayi knowledge of the Emu in the Sky and its cultural context.

  4. The night sky brightness at McDonald Observatory

    Science.gov (United States)

    Kalinowski, J. K.; Roosen, R. G.; Brandt, J. C.

    1975-01-01

    Baseline observations of the night sky brightness in B and V are presented for McDonald Observatory. In agreement with earlier work by Elvey and Rudnick (1937) and Elvey (1943), significant night-to-night and same-night variations in sky brightness are found. Possible causes for these variations are discussed. The largest variation in sky brightness found during a single night is approximately a factor of two, a value which corresponds to a factor-of-four variation in airglow brightness. The data are used to comment on the accuracy of previously published surface photometry of M 81.

  5. Sky Background Variability Measured on Maunakea at Gemini North Observatory

    Science.gov (United States)

    Smith, Adam B.; Roth, Katherine; Stephens, Andrew W.

    2016-01-01

    Gemini North has recently implemented a Quality Assessment Pipeline (QAP) that automatically reduces images in realtime to determine sky condition quantities, including background sky brightness from the optical to near-infrared. Processing archived images through the QAP and mining the results allows us to look for trends and systematic issues with the instruments and optics during the first decade of Gemini.Here we present the results of using the QAP calculated values to quantify how airglow affects the background sky brightness of images taken with Gemini's imaging instruments, GMOS and NIRI, as well as searching for other factors that may cause changes in the sky brightness. By investigating the dependence of measured sky brightness as a function of a variety of variables, including time after twilight, airmass, season, distance from the moon, air temperature, etc., we quantify the effect of sky brightness and its impact on the sensitivity of Gemini optical and near-infrared imaging data. These measurements will be used to determine new sky background relationships for Maunakea, and to improve the Gemini Integration Time Calculators (ITCs).

  6. Infrared Sky Imager (IRSI) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Victor R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-04-01

    The Infrared Sky Imager (IRSI) deployed at the Atmospheric Radiation Measurement (ARM) Climate Research Facility is a Solmirus Corp. All Sky Infrared Visible Analyzer. The IRSI is an automatic, continuously operating, digital imaging and software system designed to capture hemispheric sky images and provide time series retrievals of fractional sky cover during both the day and night. The instrument provides diurnal, radiometrically calibrated sky imagery in the mid-infrared atmospheric window and imagery in the visible wavelengths for cloud retrievals during daylight hours. The software automatically identifies cloudy and clear regions at user-defined intervals and calculates fractional sky cover, providing a real-time display of sky conditions.

  7. Urban artificial light emission function determined experimentally using night sky images

    Science.gov (United States)

    Solano Lamphar, Héctor Antonio; Kocifaj, Miroslav

    2016-09-01

    To date, diverse approximations have been developed to interpret the radiance of a night sky due to light emissions from ground-based light sources. The radiant intensity distribution as a function of zenith angle is one of the most unknown properties because of the collective effects of all artificial, private and public lights. The emission function (EF) is, however, a key property in modeling the skyglow under arbitrary conditions, and thus it is equally required by modelers, light pollution researchers, and also experimentalists who are using specialized devices to study the diffuse light of a night sky. In this paper, we present the second generation of a dedicated measuring system intended for routine monitoring of a night sky in any region. The experimental technology we have developed is used to interpret clear sky radiance data recorded at a set of discrete distances from a town (or city) with the aim to infer the fraction of upwardly emitted light (F), that is a parameter scaling the bulk EF. The retrieval of the direct upward emissions has been improved by introducing a weighting factor that is used to eliminate imperfections of experimental data and thus to make the computation of F more stable when processing the radiance data taken at two adjacent measuring points. The field experiments made in three Mexican cities are analyzed and the differences found are discussed.

  8. A Parabolic Model Presentation of Solar Radiation Data at a ...

    African Journals Online (AJOL)

    Ife, Nigeria has been analysed and simple parabolic models established for predicting them. The models appear in the form of parabolic equations with three parameters. The necessary physical interpretations of the model parameters, their ...

  9. Methodology for geometric modelling. Presentation and administration of site descriptive models; Metodik foer geometrisk modellering. Presentation och administration av platsbeskrivande modeller

    Energy Technology Data Exchange (ETDEWEB)

    Munier, Raymond [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Hermanson, Jan [Golder Associates (Sweden)

    2001-03-01

    This report presents a methodology to construct, visualise and present geoscientific descriptive models based on data from the site investigations, which the SKB currently performs, to build an underground nuclear waste disposal facility in Sweden. It is designed for interaction with SICADA (SKB:s site characterisation database) and RVS (SKB:s Rock Visualisation System). However, the concepts of the methodology are general and can be used with other tools capable of handling 3D geometries and parameters. The descriptive model is intended to be an instrument where site investigation data from all disciplines are put together to form a comprehensive visual interpretation of the studied rock mass. The methodology has four main components: 1. Construction of a geometrical model of the interpreted main structures at the site. 2. Description of the geoscientific characteristics of the structures. 3. Description and geometrical implementation of the geometric uncertainties in the interpreted model structures. 4. Quality system for the handling of the geometrical model, its associated database and some aspects of the technical auditing. The geometrical model forms a basis for understanding the main elements and structures of the investigated site. Once the interpreted geometries are in place in the model, the system allows for adding descriptive and quantitative data to each modelled object through a system of intuitive menus. The associated database allows each geometrical object a complete quantitative description of all geoscientific disciplines, variabilities, uncertainties in interpretation and full version history. The complete geometrical model and its associated database of object descriptions are to be recorded in a central quality system. Official, new and old versions of the model are administered centrally in order to have complete quality assurance of each step in the interpretation process. The descriptive model is a cornerstone in the understanding of the

  10. Pi in the Sky

    Science.gov (United States)

    O'Brien, W. P.

    2008-12-01

    Pi In The Sky (PITS) consists of a loose collection of virtual globe (VG) activities with a slight mathematical twist, wherein students search for interesting circular structures on the surface of Earth (Moon or other planets) and measure the circumference C and diameter D of each structure, using the built-in VG measure tool, in order to determine experimental values of pi from the C/D ratios. Examples of man-made circular structures visible using VG browsers include Fermilab and l"Arc de Triomphe roundabout; quasi-circular natural structures include certain volcano calderas and impact craters. Since a circle is but a special case of an ellipse, a natural extension of the activity involves making similar measurements of perimeter P, semi-major axis a, and semi-minor axis b of a visible elliptical structure (such as one of the thousands of elliptical Carolina bays, enigmatic depressions on the Atlantic Coast of North America) and solving for pi using Ramanujan's first approximation for the dependence of the perimeter of an ellipse on a and b. PITS exercises can be adapted to a wide range of student ages and teaching goals. For instance, K-6 students could measure C and D of the huge irrigation circles near Circle, Texas, to discover pi in the same way they might infer pi from measurements of coffee-can lids in math class. Middle school and high school students could move beyond man-made circles to consider the near-circularity of certain volcano calderas and impact craters in earth science units, make measurements for Olympus Mons on Mars or Crater Kepler on the moon in astronomy units, or search for circularity among Arctic thermokarst lakes as an introduction to climate change in tundra environments in environmental science units; such studies might ignite student curiosity about planetary processes. High school students of analytic geometry could examine several elliptical Carolina bays and calculate not only values of pi (as noted above) but also determine the

  11. Making sense to modelers: Presenting UML class model differences in prose

    DEFF Research Database (Denmark)

    Störrle, Harald

    2013-01-01

    Understanding the difference between two models, such as different versions of a design, can be difficult. It is a commonly held belief in the model differencing community that the best way of presenting a model difference is by using graph or tree-based visualizations. We disagree and present an...

  12. Exmoor - Europe's first International Dark Sky Reserve

    Science.gov (United States)

    Owens, S.

    2011-12-01

    On 2011 October 9 Exmoor National Park in the southwest of England was designated as Europe's first International Dark Sky Reserve by the International Dark Skies Association. This is a huge achievement, and follows three years of work by park authorities, local astronomers, lighting engineers and the resident community. Exmoor Dark Sky Reserve follows in the footsteps of Galloway Forest Dark Sky Park, set up in 2009, and Sark Dark Sky Island, established in January 2011.

  13. Modeling of present and Eemian stable water isotopes in precipitation

    DEFF Research Database (Denmark)

    Sjolte, Jesper

    The subject of this thesis is the modeling of the isotopic temperature proxies d18O, dD and deuterium excess in precipitation. Two modeling studies were carried out, one using the regional climate model, and one using a global climate model. In the regional study the model was run for the period...... the modeled isotopes do not agree with ice core data. The discrepancy between the model output and the ice core data is attributed to the boundary conditions, where changes in ice sheets and vegetation have not been accounted for....

  14. OpenDolphin: presentation models for compelling user interfaces

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    Shared applications run on the server. They still need a display, though, be it on the web or on the desktop. OpenDolphin introduces a shared presentation model to clearly differentiate between "what" to display and "how" to display. The "what" is managed on the server and is independent of the UI technology whereas the "how" can fully exploit the UI capabilities like the ubiquity of the web or the power of the desktop in terms of interactivity, animations, effects, 3D worlds, and local devices. If you run a server-centric architecture and still seek to provide the best possible user experience, then this talk is for you. About the speaker Dierk König (JavaOne Rock Star) works as a fellow for Canoo Engineering AG, Basel, Switzerland. He is a committer to many open-source projects including OpenDolphin, Groovy, Grails, GPars and GroovyFX. He is lead author of the "Groovy in Action" book, which is among ...

  15. BIG SKY CARBON SEQUESTRATION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Susan M. Capalbo

    2004-06-01

    soil C in the partnership region, and to design a risk/cost effectiveness framework to make comparative assessments of each viable sink, taking into account economic costs, offsetting benefits, scale of sequestration opportunities, spatial and time dimensions, environmental risks, and long term viability. Scientifically sound information on MMV is critical for public acceptance of these technologies. Two key deliverables were completed this quarter--a literature review/database to assess the soil carbon on rangelands, and the draft protocols, contracting options for soil carbon trading. To date, there has been little research on soil carbon on rangelands, and since rangeland constitutes a major land use in the Big Sky region, this is important in achieving a better understanding of terrestrial sinks. The protocols developed for soil carbon trading are unique and provide a key component of the mechanisms that might be used to efficiently sequester GHG and reduce CO{sub 2} concentrations. Progress on other deliverables is noted in the PowerPoint presentations. A series of meetings held during the second quarter have laid the foundations for assessing the issues surrounding the implementation of a market-based setting for soil C credits. These meetings provide a connection to stakeholders in the region and a basis on which to draw for the DOE PEIS hearings. Finally, the education and outreach efforts have resulted in a comprehensive plan and process which serves as a guide for implementing the outreach activities under Phase I. While we are still working on the public website, we have made many presentations to stakeholders and policy makers, connections to other federal and state agencies concerned with GHG emissions, climate change, and efficient and environmentally-friendly energy production. In addition, we have laid plans for integration of our outreach efforts with the students, especially at the tribal colleges and at the universities involved in our partnership

  16. All-Sky Observational Evidence for An Inverse Correlation Between Dust Temperature and Emissivity Spectral Index

    Science.gov (United States)

    Liang, Z.; Fixsen, D. J.; Gold, B.

    2012-01-01

    We show that a one-component variable-emissivity-spectral-index model (the free- model) provides more physically motivated estimates of dust temperature at the Galactic polar caps than one- or two-component fixed-emissivity-spectral-index models (fixed- models) for interstellar dust thermal emission at far-infrared and millimeter wavelengths. For the comparison we have fit all-sky one-component dust models with fixed or variable emissivity spectral index to a new and improved version of the 210-channel dust spectra from the COBE-FIRAS, the 100-240 micrometer maps from the COBE-DIRBE and the 94 GHz dust map from the WMAP. The best model, the free-alpha model, is well constrained by data at 60-3000 GHz over 86 per cent of the total sky area. It predicts dust temperature (T(sub dust)) to be 13.7-22.7 (plus or minus 1.3) K, the emissivity spectral index (alpha) to be 1.2-3.1 (plus or minus 0.3) and the optical depth (tau) to range 0.6-46 x 10(exp -5) with a 23 per cent uncertainty. Using these estimates, we present all-sky evidence for an inverse correlation between the emissivity spectral index and dust temperature, which fits the relation alpha = 1/(delta + omega (raised dot) T(sub dust) with delta = -.0.510 plus or minus 0.011 and omega = 0.059 plus or minus 0.001. This best model will be useful to cosmic microwave background experiments for removing foreground dust contamination and it can serve as an all-sky extended-frequency reference for future higher resolution dust models.

  17. Cosmology with all-sky surveys

    Science.gov (United States)

    Bilicki, Maciej

    2016-06-01

    Various aspects of cosmology require comprehensive all-sky mapping of the cosmic web to considerable depths. In order to probe the whole extragalactic sky beyond 100 Mpc, one must draw on multiwavelength datasets and state-of-the-art photometric redshift techniques. Here I summarize our dedicated program that employs the largest photometric all-sky surveys - 2MASS, WISE and SuperCOSMOS - to obtain accurate redshift estimates of millions of galaxies. The first outcome of these efforts - the 2MASS Photometric Redshift catalog (2MPZ) - was publicly released in 2013 and includes almost 1 million galaxies with a median redshift of z˜0.1. I discuss how this catalog was constructed and how it is being used for various cosmological tests. I also present how combining the WISE mid-infrared survey with SuperCOSMOS optical data allowed us to push to depths over 1 Gpc on unprecedented angular scales. These photometric redshift samples, with about 20 million sources in total, provide access to volumes large enough to study observationally the Copernican Principle of universal homogeneity and isotropy, as well as to probe various aspects of dark energy and dark matter through cross-correlations with other data such as the cosmic microwave or gamma-ray backgrounds. Last but not least, they constitute a test-bed for forthcoming wide-angle multi-million galaxy samples expected from such instruments as the SKA, Euclid, or LSST.

  18. An Investigation of LED Street Lighting's Impact on Sky Glow

    Energy Technology Data Exchange (ETDEWEB)

    Kinzey, Bruce R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Perrin, Tess E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Miller, Naomi J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kocifaj, Miroslav [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Aube, Martin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lamphar, Hector A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2017-04-25

    A significant amount of public attention has recently focused on perceived impacts of converting street lighting from incumbent lamp-based products to LED technology. Much of this attention pertains to the higher content of short wavelength light (commonly referred to as "blue light") of LEDs and its attendant influences on sky glow (a brightening of the night sky that can interfere with astronomical observation and may be associated with a host of other issues). The complexity of this topic leads to common misunderstandings and misperceptions among the public, and for this reason the U.S. Department of Energy Solid-State Lighting Program embarked on a study of sky glow using a well-established astronomical model to investigate some of the primary factors influencing sky glow. This report details the results of the investigation and attempts to present those results in terms accessible to the general lighting community. The report also strives to put the results into a larger context, and help educate interested readers on various topics relevant to the issues being discussed.

  19. Dark sky enters the lexicon

    Science.gov (United States)

    Showstack, Randy

    2012-01-01

    “Basketbrawl,” “cloud music,” “humblebrag,” and “occupy Wall Street.” These are some of the catchwords and phrases that lexicographer Grant Barrett included in a year-end newspaper column, “Which words will live on?,” in the New York Times on 31 December 2011. Among the couple dozen examples of new language was “dark sky.” Barrett wrote that it “designates a place free of nighttime light pollution. For example, the island of Sark in the English Channel is a dark-sky island.”

  20. BehavePlus fire modeling system: Past, present, and future

    Science.gov (United States)

    Patricia L. Andrews

    2007-01-01

    Use of mathematical fire models to predict fire behavior and fire effects plays an important supporting role in wildland fire management. When used in conjunction with personal fire experience and a basic understanding of the fire models, predictions can be successfully applied to a range of fire management activities including wildfire behavior prediction, prescribed...

  1. Past and present of sediment and carbon biogeochemical cycling models

    Directory of Open Access Journals (Sweden)

    F. T. Mackenzie

    2004-01-01

    Full Text Available The global carbon cycle is part of the much more extensive sedimentary cycle that involves large masses of carbon in the Earth's inner and outer spheres. Studies of the carbon cycle generally followed a progression in knowledge of the natural biological, then chemical, and finally geological processes involved, culminating in a more or less integrated picture of the biogeochemical carbon cycle by the 1920s. However, knowledge of the ocean's carbon cycle behavior has only within the last few decades progressed to a stage where meaningful discussion of carbon processes on an annual to millennial time scale can take place. In geologically older and pre-industrial time, the ocean was generally a net source of CO2 emissions to the atmosphere owing to the mineralization of land-derived organic matter in addition to that produced in situ and to the process of CaCO3 precipitation. Due to rising atmospheric CO2 concentrations because of fossil fuel combustion and land use changes, the direction of the air-sea CO2 flux has reversed, leading to the ocean as a whole being a net sink of anthropogenic CO2. The present thickness of the surface ocean layer, where part of the anthropogenic CO2 emissions are stored, is estimated as of the order of a few hundred meters. The oceanic coastal zone net air-sea CO2 exchange flux has also probably changed during industrial time. Model projections indicate that in pre-industrial times, the coastal zone may have been net heterotrophic, releasing CO2 to the atmosphere from the imbalance between gross photosynthesis and total respiration. This, coupled with extensive CaCO3 precipitation in coastal zone environments, led to a net flux of CO2 out of the system. During industrial time the coastal zone ocean has tended to reverse its trophic status toward a non-steady state situation of net autotrophy, resulting in net uptake of anthropogenic CO2 and storage of carbon in the coastal ocean, despite the significant calcification

  2. Bonissone CIDU Presentation: Design of Local Fuzzy Models

    Data.gov (United States)

    National Aeronautics and Space Administration — After reviewing key background concepts in fuzzy systems and evolutionary computing, we will focus on the use of local fuzzy models, which are related to both kernel...

  3. DBI in the Sky

    Energy Technology Data Exchange (ETDEWEB)

    Alishahiha, M

    2004-04-19

    We analyze the spectrum of density perturbations generated in models of the recently discovered ''D-cceleration'' mechanism of inflation. In this scenario, strong coupling quantum field theoretic effects sum to provide a DBI-like action for the inflaton. We show that the model has a strict lower bound on the non-Gaussianity of the CMBR power spectrum at an observable level, and is thus falsifiable. This in particular observationally distinguishes this mechanism from traditional slow roll inflation generated by weakly interacting scalar fields. The model also favors a large observable tensor component to the CMBR spectrum.

  4. All-Sky Microwave Imager Data Assimilation at NASA GMAO

    Science.gov (United States)

    Kim, Min-Jeong; Jin, Jianjun; El Akkraoui, Amal; McCarty, Will; Todling, Ricardo; Gu, Wei; Gelaro, Ron

    2017-01-01

    Efforts in all-sky satellite data assimilation at the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center have been focused on the development of GSI configurations to assimilate all-sky data from microwave imagers such as the GPM Microwave Imager (GMI) and Global Change Observation Mission-Water (GCOM-W) Advanced Microwave Scanning Radiometer 2 (AMSR-2). Electromagnetic characteristics associated with their wavelengths allow microwave imager data to be relatively transparent to atmospheric gases and thin ice clouds, and highly sensitive to precipitation. Therefore, GMAOs all-sky data assimilation efforts are primarily focused on utilizing these data in precipitating regions. The all-sky framework being tested at GMAO employs the GSI in a hybrid 4D-EnVar configuration of the Goddard Earth Observing System (GEOS) data assimilation system, which will be included in the next formal update of GEOS. This article provides an overview of the development of all-sky radiance assimilation in GEOS, including some performance metrics. In addition, various projects underway at GMAO designed to enhance the all-sky implementation will be introduced.

  5. SKYMONITOR: A Global Network for Sky Brightness Measurements

    Science.gov (United States)

    Davis, Donald R.; Mckenna, D.; Pulvermacher, R.; Everett, M.

    2010-01-01

    We are implementing a global network to measure sky brightness at dark-sky critical sites with the goal of creating a multi-decade database. The heart of this project is the Night Sky Brightness Monitor (NSBM), an autonomous 2 channel photometer which measures night sky brightness in the visual wavelengths (Mckenna et al, AAS 2009). Sky brightness is measured every minute at two elevation angles typically zenith and 20 degrees to monitor brightness and transparency. The NSBM consists of two parts, a remote unit and a base station with an internet connection. Currently these devices use 2.4 Ghz transceivers with a range of 100 meters. The remote unit is battery powered with daytime recharging using a solar panel. Data received by the base unit is transmitted via email protocol to IDA offices in Tucson where it will be collected, archived and made available to the user community via a web interface. Two other versions of the NSBM are under development: one for radio sensitive areas using an optical fiber link and the second that reads data directly to a laptop for sites without internet access. NSBM units are currently undergoing field testing at two observatories. With support from the National Science Foundation, we will construct and install a total of 10 units at astronomical observatories. With additional funding, we will locate additional units at other sites such as National Parks, dark-sky preserves and other sites where dark sky preservation is crucial. We will present the current comparison with the National Park Service sky monitoring camera. We anticipate that the SKYMONITOR network will be functioning by the end of 2010.

  6. Sky Observations by the Book

    Science.gov (United States)

    Trundle, Kathy Cabe; Sackes, Mesut

    2008-01-01

    The "National Science Education Standards (NSES)" state that students in grades K-4 are expected to understand that astronomical objects in the sky, including the Sun, Moon, and stars--have properties, locations, and patterns of movement that can be observed and described. They further suggest using an inquiry-based approach to teach…

  7. Deep-Sky Video Astronomy

    CERN Document Server

    Massey, Steve

    2009-01-01

    A guide to using modern integrating video cameras for deep-sky viewing and imaging with the kinds of modest telescopes available commercially to amateur astronomers. It includes an introduction and a brief history of the technology and camera types. It examines the pros and cons of this unrefrigerated yet highly efficient technology

  8. The sky in Mayan literature.

    Science.gov (United States)

    Aveni, A. F.

    Based on a workshop, Hamilton, NY (USA), Nov 1989. The goal of this meeting was to assess some of the recent advances in Maya glyphic decipherment to understand the nature and extent of Maya knowledge about the natural world, specifically the sky environment as revealed in the codices and related texts.

  9. Present-day heat flow model of Mars

    National Research Council Canada - National Science Library

    Laura M Parro; Alberto Jiménez-díaz; Federico Mansilla; Javier Ruiz

    2017-01-01

    Until the acquisition of in-situ measurements, the study of the present-day heat flow of Mars must rely on indirect methods, mainly based on the relation between the thermal state of the lithosphere...

  10. BIG SKY CARBON SEQUESTRATION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Susan M. Capalbo

    2004-06-30

    The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership fall into four areas: evaluation of sources and carbon sequestration sinks; development of GIS-based reporting framework; designing an integrated suite of monitoring, measuring, and verification technologies; and initiating a comprehensive education and outreach program. At the first two Partnership meetings the groundwork was put in place to provide an assessment of capture and storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research. During the third quarter, planning efforts are underway for the next Partnership meeting which will showcase the architecture of the GIS framework and initial results for sources and sinks, discuss the methods and analysis underway for assessing geological and terrestrial sequestration potentials. The meeting will conclude with an ASME workshop (see attached agenda). The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the efforts of other western DOE partnerships. Efforts are also being made to find funding to include Wyoming in the coverage areas for both geological and terrestrial sinks and sources. The Partnership recognizes the critical importance of measurement

  11. SkyNet: A Modular Nuclear Reaction Network Library

    Science.gov (United States)

    Lippuner, Jonas; Roberts, Luke F.

    2017-12-01

    Almost all of the elements heavier than hydrogen that are present in our solar system were produced by nuclear burning processes either in the early universe or at some point in the life cycle of stars. In all of these environments, there are dozens to thousands of nuclear species that interact with each other to produce successively heavier elements. In this paper, we present SkyNet, a new general-purpose nuclear reaction network that evolves the abundances of nuclear species under the influence of nuclear reactions. SkyNet can be used to compute the nucleosynthesis evolution in all astrophysical scenarios where nucleosynthesis occurs. SkyNet is free and open source, and aims to be easy to use and flexible. Any list of isotopes can be evolved, and SkyNet supports different types of nuclear reactions. SkyNet is modular so that new or existing physics, like nuclear reactions or equations of state, can easily be added or modified. Here, we present in detail the physics implemented in SkyNet with a focus on a self-consistent transition to and from nuclear statistical equilibrium to non-equilibrium nuclear burning, our implementation of electron screening, and coupling of the network to an equation of state. We also present comprehensive code tests and comparisons with existing nuclear reaction networks. We find that SkyNet agrees with published results and other codes to an accuracy of a few percent. Discrepancies, where they exist, can be traced to differences in the physics implementations.

  12. Estimating net present value variability for deterministic models

    NARCIS (Netherlands)

    van Groenendaal, W.J.H.

    1995-01-01

    For decision makers the variability in the net present value (NPV) of an investment project is an indication of the project's risk. So-called risk analysis is one way to estimate this variability. However, risk analysis requires knowledge about the stochastic character of the inputs. For large,

  13. Minimal Z' models present bounds and early LHC reach

    CERN Document Server

    Salvioni, Ennio; Zwirner, Fabio

    2009-01-01

    We consider `minimal' Z' models, whose phenomenology is controlled by only three parameters beyond the Standard Model ones: the Z' mass and two effective coupling constants. They encompass many popular models motivated by grand unification, as well as many arising in other theoretical contexts. This parameterization takes also into account both mass and kinetic mixing effects, which we show to be sizable in some cases. After discussing the interplay between the bounds from electroweak precision tests and recent direct searches at the Tevatron, we extend our analysis to estimate the early LHC discovery potential. We consider a center-of-mass energy from 7 towards 10 TeV and an integrated luminosity from 50 to several hundred pb^-1, taking all existing bounds into account. We find that the LHC will start exploring virgin land in parameter space for M_Z' around 700 GeV, with lower masses still excluded by the Tevatron and higher masses still excluded by electroweak precision tests. Increasing the energy up to 10...

  14. Surviving the present: Modeling tools for organizational change

    Energy Technology Data Exchange (ETDEWEB)

    Pangaro, P. (Pangaro Inc., Washington, DC (United States))

    1992-01-01

    The nuclear industry, like the rest of modern American business, is beset by a confluence of economic, technological, competitive, regulatory, and political pressures. For better or worse, business schools and management consultants have leapt to the rescue, offering the most modern conveniences that they can purvey. Recent advances in the study of organizations have led to new tools for their analysis, revision, and repair. There are two complementary tools that do not impose values or injunctions in themselves. One, called the organization modeler, captures the hierarchy of purposes that organizations and their subparts carry out. Any deficiency or pathology is quickly illuminated, and requirements for repair are made clear. The second, called THOUGHTSTICKER, is used to capture the semantic content of the conversations that occur across the interactions of parts of an organization. The distinctions and vocabulary in the language of an organization, and the relations within that domain, are elicited from the participants so that all three are available for debate and refinement. The product of the applications of these modeling tools is not the resulting models but rather the enhancement of the organization as a consequence of the process of constructing them.

  15. Colors of the daytime overcast sky

    Science.gov (United States)

    Lee, Raymond L., Jr.; Hernández-Andrés, Javier

    2005-09-01

    Time-series measurements of daylight (skylight plus direct sunlight) spectra beneath overcast skies reveal an unexpectedly wide gamut of pastel colors. Analyses of these spectra indicate that at visible wavelengths, overcasts are far from spectrally neutral transmitters of the daylight incident on their tops. Colorimetric analyses show that overcasts make daylight bluer and that the amount of bluing increases with cloud optical depth. Simulations using the radiative-transfer model MODTRAN4 help explain the observed bluing: multiple scattering within optically thick clouds greatly enhances spectrally selective absorption by water droplets. However, other factors affecting overcast colors seen from below range from minimal (cloud-top heights) to moot (surface colors).

  16. Teach and Touch the Earth and Sky

    Science.gov (United States)

    Florina Tendea, Camelia

    2017-04-01

    My name is Camelia Florina Tendea. I am primary school teacher at "Horea, Closca and Crisan" Secondary School, in Brad, a town in the west side of Transylvania. I am permanently interested to develop my knowledge and teaching skills about space sciences (Earth and Sky) because the new generations of students are very well informed and couriouse about these topics. In this context the teachers must be prepared to deal with such requests in school. Introducing of activity: For a primary school teacher is a real challenge teaching about Earth and Sky, so I consider that a collaboration with science teachers, engineers and other specialists in the sciences is absolutely essential and beneficial in the educational design. In my opinion, the contents about Earth ans Sky-Space in a single word- are very attractive for students and they are a permanent source of discoveries and provide a multidisciplinary vision, so required in the education. Possible contents to teach in primary school: about Earth: -Terra -the third Planet from the Sun; How Earth spins; Land and water; The Earth seen from space, Trip between Earth and Moon,Weather Phenomena; the Poles; about Sky: Solar System, Asteroids, Comets, Meteorites; Rosetta Mission or rendez-vous with a comet; Sun.Moon. Earth. Eclipse;Light Pollution and protection of the night sky; Life in Space. Astronauts and experiences; Mission X:- Train Like an Astronaut;About ISS. For teachers it is important to know from the beginning how they teach, a viable support is the teaching of STEM subjects, which provides access to careers in astronomy, science/technology space. We could teach about earth and sky using different kinds of experiments, simulations, hands-on activities, competitions, exhibitions, video presentations. Competences developed in primary school through these contents: Comunication, individual studying, understanding and valorisation of scientific information, relating to the natural environment. In addition, they are

  17. The fast transient sky with Gaia

    Science.gov (United States)

    Wevers, Thomas; Jonker, Peter G.; Hodgkin, Simon T.; Kostrzewa-Rutkowska, Zuzanna; Harrison, Diana L.; Rixon, Guy; Nelemans, Gijs; Roelens, Maroussia; Eyer, Laurent; van Leeuwen, Floor; Yoldas, Abdullah

    2018-01-01

    The ESA Gaia satellite scans the whole sky with a temporal sampling ranging from seconds and hours to months. Each time a source passes within the Gaia field of view, it moves over 10 charge coupled devices (CCDs) in 45 s and a light curve with 4.5 s sampling (the crossing time per CCD) is registered. Given that the 4.5 s sampling represents a virtually unexplored parameter space in optical time domain astronomy, this data set potentially provides a unique opportunity to open up the fast transient sky. We present a method to start mining the wealth of information in the per CCD Gaia data. We perform extensive data filtering to eliminate known onboard and data processing artefacts, and present a statistical method to identify sources that show transient brightness variations on ≲2 h time-scales. We illustrate that by using the Gaia photometric CCD measurements, we can detect transient brightness variations down to an amplitude of 0.3 mag on time-scales ranging from 15 s to several hours. We search an area of ∼23.5 deg2 on the sky and find four strong candidate fast transients. Two candidates are tentatively classified as flares on M-dwarf stars, while one is probably a flare on a giant star and one potentially a flare on a solar-type star. These classifications are based on archival data and the time-scales involved. We argue that the method presented here can be added to the existing Gaia Science Alerts infrastructure for the near real-time public dissemination of fast transient events.

  18. Big Sky Carbon Sequestration Partnership

    Energy Technology Data Exchange (ETDEWEB)

    Susan M. Capalbo

    2005-11-01

    The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I fall into four areas: evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; development of GIS-based reporting framework that links with national networks; designing an integrated suite of monitoring, measuring, and verification technologies and assessment frameworks; and initiating a comprehensive education and outreach program. The groundwork is in place to provide an assessment of storage capabilities for CO2 utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research agenda in Carbon Sequestration. The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the efforts of other DOE regional partnerships. The Partnership recognizes the critical importance of measurement, monitoring, and verification technologies to support not only carbon trading but all policies and programs that DOE and other agencies may want to pursue in support of GHG mitigation. The efforts in developing and implementing MMV technologies for geological sequestration reflect this concern. Research is also underway to identify and validate best management practices for soil C in the

  19. Curiosities of the sky

    CERN Document Server

    Serviss, Garrett P

    2012-01-01

    Long before figures like Carl Sagan and Neil deGrasse Tyson simplified astronomy for popular consumption, Garrett P. Serviss was traveling the United States with an early version of a PowerPoint presentation to teach people about eclipses, the orbit of the planets, and other celestial concepts. This basic introduction to the subject is simple and enjoyable enough to ensure that science-phobes or young readers won't be turned off.

  20. Presenting of Indifference Management Model of Education System in Ardabil Province Using Structural Equation Modeling

    Science.gov (United States)

    Abolfazli, Elham; Saidabadi, Reza Yousefi; Fallah, Vahid

    2016-01-01

    The purpose of the present study is to investigate indifference management structural model in education system of Ardabil Province. The research method was integration study using Alli modeling. Statistical society of research was 420 assistant professors of educational science, managers, and deputies of Ardabil's second period of high schools…

  1. ACTPol: On-Sky Performance and Characterization

    Science.gov (United States)

    Grace, E.; Beall, J.; Bond, J. R.; Cho, H. M.; Datta, R.; Devlin, M. J.; Dunner, R.; Fox, A. E.; Gallardo, P.; Hasselfield, M.; hide

    2014-01-01

    ACTPol is the polarization-sensitive receiver on the Atacama Cosmology Telescope. ACTPol enables sensitive millimeter wavelength measurements of the temperature and polarization anisotropies of the Cosmic Microwave Background (CMB) at arcminute angular scales. These measurements are designed to explore the process of cosmic structure formation, constrain or determine the sum of the neutrino masses, probe dark energy, and provide a foundation for a host of other cosmological tests. We present an overview of the first season of ACTPol observations focusing on the optimization and calibration of the first detector array as well as detailing the on-sky performance.

  2. Blue Sky Matter

    DEFF Research Database (Denmark)

    Jensen, Ole B.; Vannini, Phillip

    2016-01-01

    In this article we present a theoretical framework for an understanding of the relationship between the material design of mobilities technologies and the multisensorial human body. Situating our work in the emerging field of “mobilities design” within the broader so-called mobilities turn, we......, and end with a conclusion that offers a fl at ontological view of mobilities design. We argue that according the material design of mobilities technologies must be inscribed on equal terms with the sensing human subject if we are to claim that we have reached a better understanding of how mobility feels....

  3. Validation of spectral sky radiance derived from all-sky camera images – a case study

    Directory of Open Access Journals (Sweden)

    K. Tohsing

    2014-07-01

    Full Text Available Spectral sky radiance (380–760 nm is derived from measurements with a hemispherical sky imager (HSI system. The HSI consists of a commercial compact CCD (charge coupled device camera equipped with a fish-eye lens and provides hemispherical sky images in three reference bands such as red, green and blue. To obtain the spectral sky radiance from these images, non-linear regression functions for various sky conditions have been derived. The camera-based spectral sky radiance was validated using spectral sky radiance measured with a CCD spectroradiometer. The spectral sky radiance for complete distribution over the hemisphere between both instruments deviates by less than 20% at 500 nm for all sky conditions and for zenith angles less than 80°. The reconstructed spectra of the wavelengths 380–760 nm between both instruments at various directions deviate by less than 20% for all sky conditions.

  4. MODELS OF STATE REFORMS IN AGRICULTURE: PAST AND PRESENT

    Directory of Open Access Journals (Sweden)

    А Г Киселев

    2017-12-01

    Full Text Available The article outlines social and economic consequences of collectivization to compare this state policy with the changes in agriculture in the 1990s, and to estimate chances of the Russian agriculture to overcome the current crisis. The article is based on archive data on collectivization and on the program developed by the Academy of High Ecotechnologies. The authors believe that at the time of collectivization, it was a way to optimize agriculture: largely due to collectivization, though with all its losses and ‘extremes’, the soviet agriculture was partially industrialized and provided the country with food in the hardest years of the Great Patriotic War and in the post-war period, thus ensuring the food security of the Soviet state. The ‘emergency’ model of the so-called ‘return to civilization’ that was adopted under the reforms of the 1990s aimed at turning the collective farmer into an individual farmer or a rural wageworker, but such a social ‘migration’ strategy imposed ‘from above’ deformed the rural social stratum and determined serious economic problems. Today the authors consider the neo-collective farms as a promising perspec-tive. They also support the program developed by the Academy of High Ecotechnologies for intensification of agricultural production on the basis of progressive domestic and foreign technologies, which will allow to increase the agricultural production in the next three to five years by several times. In particular, for more effective use of agricultural technologies and processing industries, the program suggests develop-ing the enlarged organizational-economic structures - ‘agropromkhozes’.

  5. The Sky, A User's Guide

    Science.gov (United States)

    Levy, David H.

    This is an ideal book for starting astronomy. It stirs the imagination, and puts observation of the sky into the framework of leisure activity as well as a personal adventure. Written by an award winning astronomer, it is a non-technical guide to the night sky, full of practical hints. The author's lively style enthuses, entertains and informs. * know the constellations, even if you live in a large city * observe the Sun safely * find out how comets are discovered * watch a star vary in brightness from week to week * explore star clusters and remote galaxies. Author David Levy is one of the world's foremost amateur astronomers. He has discovered 17 comets. Minor Planet 3673 Levy is named in his honour. An English graduate, Levy has written a beautiful introduction to the glories of the observable universe of constellations, stars and galaxies.

  6. Mining the SDSS SkyServer SQL queries log

    Science.gov (United States)

    Hirota, Vitor M.; Santos, Rafael; Raddick, Jordan; Thakar, Ani

    2016-05-01

    SkyServer, the Internet portal for the Sloan Digital Sky Survey (SDSS) astronomic catalog, provides a set of tools that allows data access for astronomers and scientific education. One of SkyServer data access interfaces allows users to enter ad-hoc SQL statements to query the catalog. SkyServer also presents some template queries that can be used as basis for more complex queries. This interface has logged over 330 million queries submitted since 2001. It is expected that analysis of this data can be used to investigate usage patterns, identify potential new classes of queries, find similar queries, etc. and to shed some light on how users interact with the Sloan Digital Sky Survey data and how scientists have adopted the new paradigm of e-Science, which could in turn lead to enhancements on the user interfaces and experience in general. In this paper we review some approaches to SQL query mining, apply the traditional techniques used in the literature and present lessons learned, namely, that the general text mining approach for feature extraction and clustering does not seem to be adequate for this type of data, and, most importantly, we find that this type of analysis can result in very different queries being clustered together.

  7. BIG SKY CARBON SEQUESTRATION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Susan M. Capalbo

    2004-10-31

    The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership fall into four areas: evaluation of sources and carbon sequestration sinks; development of GIS-based reporting framework; designing an integrated suite of monitoring, measuring, and verification technologies; and initiating a comprehensive education and outreach program. At the first two Partnership meetings the groundwork was put in place to provide an assessment of capture and storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research. During the third quarter, planning efforts are underway for the next Partnership meeting which will showcase the architecture of the GIS framework and initial results for sources and sinks, discuss the methods and analysis underway for assessing geological and terrestrial sequestration potentials. The meeting will conclude with an ASME workshop. The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the efforts of other western DOE partnerships. Efforts are also being made to find funding to include Wyoming in the coverage areas for both geological and terrestrial sinks and sources. The Partnership recognizes the critical importance of measurement, monitoring, and verification

  8. Modelling constraints on the emission inventory and on vertical dispersion for CO and SO2 in the Mexico City Metropolitan Area using Solar FTIR and zenith sky UV spectroscopy

    Directory of Open Access Journals (Sweden)

    B. de Foy

    2007-01-01

    Full Text Available Emissions of air pollutants in and around urban areas lead to negative health impacts on the population. To estimate these impacts, it is important to know the sources and transport mechanisms of the pollutants accurately. Mexico City has a large urban fleet in a topographically constrained basin leading to high levels of carbon monoxide (CO. Large point sources of sulfur dioxide (SO2 surrounding the basin lead to episodes with high concentrations. An Eulerian grid model (CAMx and a particle trajectory model (FLEXPART are used to evaluate the estimates of CO and SO2 in the current emission inventory using mesoscale meteorological simulations from MM5. Vertical column measurements of CO are used to constrain the total amount of emitted CO in the model and to identify the most appropriate vertical dispersion scheme. Zenith sky UV spectroscopy is used to estimate the emissions of SO2 from a large power plant and the Popocatépetl volcano. Results suggest that the models are able to identify correctly large point sources and that both the power plant and the volcano impact the MCMA. Modelled concentrations of CO based on the current emission inventory match observations suggesting that the current total emissions estimate is correct. Possible adjustments to the spatial and temporal distribution can be inferred from model results. Accurate source and dispersion modelling provides feedback for development of the emission inventory, verification of transport processes in air quality models and guidance for policy decisions.

  9. The Impact of Assimilation of GPM Clear Sky Radiance on HWRF Hurricane Track and Intensity Forecasts

    Science.gov (United States)

    Yu, C. L.; Pu, Z.

    2016-12-01

    The impact of GPM microwave imager (GMI) clear sky radiances on hurricane forecasting is examined by ingesting GMI level 1C recalibrated brightness temperature into the NCEP Gridpoint Statistical Interpolation (GSI)- based ensemble-variational hybrid data assimilation system for the operational Hurricane Weather Research and Forecast (HWRF) system. The GMI clear sky radiances are compared with the Community Radiative Transfer Model (CRTM) simulated radiances to closely study the quality of the radiance observations. The quality check result indicates the presence of bias in various channels. A static bias correction scheme, in which the appropriate bias correction coefficients for GMI data is evaluated by applying regression method on a sufficiently large sample of data representative to the observational bias in the regions of concern, is used to correct the observational bias in GMI clear sky radiances. Forecast results with and without assimilation of GMI radiance are compared using hurricane cases from recent hurricane seasons (e.g., Hurricane Joaquin in 2015). Diagnoses of data assimilation results show that the bias correction coefficients obtained from the regression method can correct the inherent biases in GMI radiance data, significantly reducing observational residuals. The removal of biases also allows more data to pass GSI quality control and hence to be assimilated into the model. Forecast results for hurricane Joaquin demonstrates that the quality of analysis from the data assimilation is sensitive to the bias correction, with positive impacts on the hurricane track forecast when systematic biases are removed from the radiance data. Details will be presented at the symposium.

  10. A simple formula for determining globally clear skies

    Energy Technology Data Exchange (ETDEWEB)

    Long, C.N.; George, A.T.; Mace, G.G. [Penn State Univ., University Park, PA (United States)] [and others

    1996-04-01

    Surface measurements to serve as {open_quotes}ground truth{close_quotes} are of primary importance in the development of retrieval algorithms using satellite measurements to predict surface irradiance. The most basic algorithms of this type deal with clear sky (i.e., cloudless) top-to-surface shortwave (SW) transfer, serving as a necessary prerequisite towards treating both clear and cloudy conditions. Recently, atmosphere SW cloud forcing to infer the possibility of excess atmospheric absorption (compared with model results) in cloudy atmospheres. The surface component of this ratio relies on inferring the expected clear sky SW irradiance to determine the effects of clouds on the SW energy budget. Solar renewable energy applications make use of clear and cloud fraction climatologies to assess solar radiation resources. All of the above depend to some extent on the identification of globally clear sky conditions and the attendant measurements of downwelling SW irradiance.

  11. Providing Diurnal Sky Cover Data at ARM Sites

    Energy Technology Data Exchange (ETDEWEB)

    Klebe, Dimitri I. [Solmirus Corporation, Colorado Springs, CO (United States)

    2015-03-06

    The Solmirus Corporation was awarded two-year funding to perform a comprehensive data analysis of observations made during Solmirus’ 2009 field campaign (conducted from May 21 to July 27, 2009 at the ARM SGP site) using their All Sky Infrared Visible Analyzer (ASIVA) instrument. The objective was to develop a suite of cloud property data products for the ASIVA instrument that could be implemented in real time and tailored for cloud modelers. This final report describes Solmirus’ research and findings enabled by this grant. The primary objective of this award was to develop a diurnal sky cover (SC) data product utilizing the ASIVA’s infrared (IR) radiometrically-calibrated data and is described in detail. Other data products discussed in this report include the sky cover derived from ASIVA’s visible channel and precipitable water vapor, cloud temperature (both brightness and color), and cloud height inferred from ASIVA’s IR channels.

  12. Radiative sky cooling: fundamental physics, materials, structures, and applications

    Science.gov (United States)

    Sun, Xingshu; Sun, Yubo; Zhou, Zhiguang; Alam, Muhammad Ashraful; Bermel, Peter

    2017-07-01

    Radiative sky cooling reduces the temperature of a system by promoting heat exchange with the sky; its key advantage is that no input energy is required. We will review the origins of radiative sky cooling from ancient times to the modern day, and illustrate how the fundamental physics of radiative cooling calls for a combination of properties that may not occur in bulk materials. A detailed comparison with recent modeling and experiments on nanophotonic structures will then illustrate the advantages of this recently emerging approach. Potential applications of these radiative cooling materials to a variety of temperature-sensitive optoelectronic devices, such as photovoltaics, thermophotovoltaics, rectennas, and infrared detectors, will then be discussed. This review will conclude by forecasting the prospects for the field as a whole in both terrestrial and space-based systems.

  13. The Tomaraho Conception of the Sky

    CERN Document Server

    Sequera, Guillermo

    2011-01-01

    The small community of the Tomaraho, an ethnic group culturally derived from the Zamucos, became known in the South American and world anthropological scenario in recent times. This group, far from the banks of the Paraguay river, remained concealed from organized modern societies for many years. Like any other groups of people in close contact with nature, the Tomaraho developed a profound and rich world view which parallels other more widely researched aboriginal cultures as well as showing distinctive features of their own. This is also apparent in their imagery of the sky and of the characters that are closely connected with the celestial sphere. This paper is based on the lengthy anthropological studies of G. Sequera. We have recently undertaken a project to carry out a detailed analysis of the different astronomical elements present in the imagined sky of the Tomaraho and other Chamacoco ethnic groups. We will briefly review some aspects of this aboriginal culture: places where they live, regions of inf...

  14. An All-Sky Portable (ASP) Optical Catalogue

    Science.gov (United States)

    Flesch, Eric Wim

    2017-06-01

    This optical catalogue combines the all-sky USNO-B1.0/A1.0 and most-sky APM catalogues, plus overlays of SDSS optical data, into a single all-sky map presented in a sparse binary format that is easily downloaded at 9 Gb zipped. Total count is 1 163 237 190 sources and each has J2000 astrometry, red and blue magnitudes with PSFs and variability indicator, and flags for proper motion, epoch, and source survey and catalogue for each of the photometry and astrometry. The catalogue is available on http://quasars.org/asp.html, and additional data for this paper is available at http://dx.doi.org/10.4225/50/5807fbc12595f.

  15. The spectrum of the Kitt Peak night sky

    Science.gov (United States)

    Massey, Philip; Gronwall, Caryl; Pilachowski, Catherine A.

    1990-08-01

    Absolute spectrophotometry of the Kitt Peak night sky at a variety of azimuths an zenith angles is presented, and the effect of population increase in Pima County on the dark-sky properties of Kitt Peak National Observatory in Arizona is studied. The results confirm that Kitt Peak remains a dark site, even after significant recent population growth of the surrounding area. The major line contributor to the B band is Hg, while the dominant source of contamination to the V-band measures are atmospheric lines, most notably O I 5577 A. Using fluxed observations of street lamps it was found that the relative contribution to light pollution in the yellow-red (5000 A - 6500 A) is 10 percent Hg, 30 percent LPS, and 60 percent HPS. No significant azimuthal effects are seen; it is noted that the sky remains equally dark toward Phoenix and Tucson as it does in other directions for zenith distances of 60 deg or less.

  16. APPLIANCE OF COMPETITORS TECHNIQUES IN LEADING THE SKIES IN TURNING

    Directory of Open Access Journals (Sweden)

    Rašid Hadžić

    2009-11-01

    Full Text Available Competitors techniques in skiing characterize driving on edges, without gliding in certain fazes of turning. Today that characteristic is more and more present in all di- scipline, (downhill, super G, giant slalom and slalom so we can talk about appliance of basic technique of leading skies on all disciplines, with differences in position of skies in amplitude of moving and frequencies of changes of edges. From that point of view we distinct three typical shape of moving in turning, which have mutual distinction in influence on ski loading, and that has influence on tur- ning line and acceleration or checking in certain fazes of turning.

  17. Clear-Sky Narrowband Albedo Variations Derived from VIRS and MODIS Data

    Science.gov (United States)

    Sun-Mack, Sunny; Chen, Yan; Arduini, Robert F.; Minnis, Patrick

    2004-01-01

    A critical parameter for detecting clouds and aerosols and for retrieving their microphysical properties is the clear-sky radiance. The Clouds and the Earth's Radiant Energy System (CERES) Project uses the visible (VIS; 0.63 m) and near-infrared (NIR; 1.6 or 2.13 m) channels available on same satellites as the CERES scanners. Another channel often used for cloud and aerosol, and vegetation cover retrievals is the vegetation (VEG; 0.86- m) channel that has been available on the Advanced Very High Resolution Radiometer (AVHRR) for many years. Generally, clear-sky albedo for a given surface type is determined for conditions when the vegetation is either thriving or dormant and free of snow. Snow albedo is typically estimated without considering the underlying surface type. The albedo for a surface blanketed by snow, however, should vary with surface type because the vegetation often emerges from the snow to varying degrees depending on the vertical dimensions of the vegetation. For example, a snowcovered prairie will probably be brighter than a snowcovered forest because the snow typically falls off the trees exposing the darker surfaces while the snow on a grassland at the same temperatures will likely be continuous and, therefore, more reflective. Accounting for the vegetation-induced differences should improve the capabilities for distinguishing snow and clouds over different surface types and facilitate improvements in the accuracy of radiative transfer calculations between the snow-covered surface and the atmosphere, eventually leading to improvements in models of the energy budgets over land. This paper presents a more complete analysis of the CERES spectral clear-sky reflectances to determine the variations in clear-sky top-of-atmosphere (TOA) albedos for both snow-free and snow-covered surfaces for four spectral channels using data from Terra and Aqua.. The results should be valuable for improved cloud retrievals and for modeling radiation fields.

  18. MonetDB/SQL Meets SkyServer: the Challenges of a Scientific Database.

    NARCIS (Netherlands)

    M.G. Ivanova (Milena); N.J. Nes (Niels); R.A. Goncalves (Romulo); M.L. Kersten (Martin)

    2007-01-01

    textabstractThis paper presents our experiences in porting the Sloan Digital Sky Survey(SDSS)/ SkyServer to the state-of-the-art open source database system MonetDB/SQL. SDSS acts as a well-documented benchmark for scientific database management. We have achieved a fully functional prototype for the

  19. The LOFAR Multifrequency Snapshot Sky Survey (MSSS). I. Survey description and first results

    NARCIS (Netherlands)

    Heald, G. H.; Pizzo, R. F.; Orrú, E.; Breton, R. P.; Carbone, D.; Ferrari, C.; Hardcastle, M. J.; Jurusik, W.; Macario, G.; Mulcahy, D.; Rafferty, D.; Asgekar, A.; Brentjens, M.; Fallows, R. A.; Frieswijk, W.; Toribio, M. C.; Adebahr, B.; Arts, M.; Bell, M. R.; Bonafede, A.; Bray, J.; Broderick, J.; Cantwell, T.; Carroll, P.; Cendes, Y.; Clarke, A. O.; Croston, J.; Daiboo, S.; de Gasperin, F.; Gregson, J.; Harwood, J.; Hassall, T.; Heesen, V.; Horneffer, A.; van der Horst, A. J.; Iacobelli, M.; Jelić, V.; Jones, D.; Kant, D.; Kokotanekov, G.; Martin, P.; McKean, J. P.; Morabito, L. K.; Nikiel-Wroczyński, B.; Offringa, A.; Pandey, V. N.; Pandey-Pommier, M.; Pietka, M.; Pratley, L.; Riseley, C.; Rowlinson, A.; Sabater, J.; Scaife, A. M. M.; Scheers, L. H. A.; Sendlinger, K.; Shulevski, A.; Sipior, M.; Sobey, C.; Stewart, A. J.; Stroe, A.; Swinbank, J.; Tasse, C.; Trüstedt, J.; Varenius, E.; van Velzen, S.; Vilchez, N.; van Weeren, R. J.; Wijnholds, S.; Williams, W. L.; de Bruyn, A. G.; Nijboer, R.; Wise, M.; Alexov, A.; Anderson, J.; Avruch, I. M.; Beck, R.; Bell, M. E.; van Bemmel, I.; Bentum, M. J.; Bernardi, G.; Best, P.; Breitling, F.; Brouw, W. N.; Brüggen, M.; Butcher, H. R.; Ciardi, B.; Conway, J. E.; de Geus, E.; de Jong, A.; de Vos, M.; Deller, A.; Dettmar, R.-J.; Duscha, S.; Eislöffel, J.; Engels, D.; Falcke, H.; Fender, R.; Garrett, M. A.; Grießmeier, J.; Gunst, A. W.; Hamaker, J. P.; Hessels, J. W. T.; Hoeft, M.; Hörandel, J.; Holties, H. A.; Intema, H.; Jackson, N. J.; Jütte, E.; Karastergiou, A.; Klijn, W. F. A.; Kondratiev, V. I.; Koopmans, L. V. E.; Kuniyoshi, M.; Kuper, G.; Law, C.; van Leeuwen, J.; Loose, M.; Maat, P.; Markoff, S.; McFadden, R.; McKay-Bukowski, D.; Mevius, M.; Miller-Jones, J. C. A.; Morganti, R.; Munk, H.; Nelles, A.; Noordam, J. E.; Norden, M. J.; Paas, H.; Polatidis, A. G.; Reich, W.; Renting, A.; Röttgering, H.; Schoenmakers, A.; Schwarz, D.; Sluman, J.; Smirnov, O.; Stappers, B. W.; Steinmetz, M.; Tagger, M.; Tang, Y.; ter Veen, S.; Thoudam, S.; Vermeulen, R.; Vocks, C.; Vogt, C.; Wijers, R. A. M. J.; Wucknitz, O.; Yatawatta, S.; Zarka, P.

    2015-01-01

    We present the Multifrequency Snapshot Sky Survey (MSSS), the first northern-sky Low Frequency Array (LOFAR) imaging survey. In this introductory paper, we first describe in detail the motivation and design of the survey. Compared to previous radio surveys, MSSS is exceptional due to its intrinsic

  20. The Sky Polarization Observatory (SPOrt) experiment

    Science.gov (United States)

    Carretti, E.

    We present the Sky Polarization Observatory (SPOrt), an experiment aimed at measuring the Cosmic Microwave Background Polarization (CMBP) on large angular scales, scales on which the information about the formation epoch of the first structrures (e.g. galaxies) reside. SPOrt is an ASI funded programme and has been selected by ESA to be flown onboard the International Space Station (ISS). It consists of four radiometers in the 22-90 GHz range and it will be the first space experiment expressly devoted to polarization measurements of CMB. In particular it has been designed to minimize systematic effects at a level negligible for CMBP, which is about 2 orders of magnitude lower the CMB anisotropy signal, main target of experiments like WMAP and PLANCK. The experiment will be presented in both its two relevant aspects: scientific goals and design description with particular emphasis to its cleanness with respect to instrumental contaminations.

  1. A large anisotropy in the sky distribution of 3CRR quasars and other radio galaxies

    Science.gov (United States)

    Singal, Ashok K.

    2015-06-01

    We report the presence of large anisotropies in the sky distributions of powerful extended quasars as well as some other sub-classes of radio galaxies in the 3CRR survey, the most reliable and most intensively studied complete sample of strong steep-spectrum radio sources. The anisotropies lie about a plane passing through the equinoxes and the north celestial pole. Out of a total of 48 quasars in the sample, 33 of them lie in one half of the observed sky and the remaining 15 in the other half. The probability that in a random distribution of 3CRR quasars in the sky, statistical fluctuations could give rise to an asymmetry in observed numbers up to this level is only ˜1 %. Also only about 1/4th of Fanaroff-Riley 1 (FR1) type of radio galaxies lie in the first half of the observed sky and the remainder in the second half. If we include all the observed asymmetries in the sky distributions of quasars and radio galaxies in the 3CRR sample, the probability of their occurrence by a chance combination reduces to ˜2×10-5. Two pertinent but disturbing questions that could be raised here are—firstly why should there be such large anisotropies present in the sky distribution of some of the strongest and most distant discrete sources, implying inhomogeneities in the universe at very large scales (covering a fraction of the universe)? Secondly why should such anisotropies lie about a great circle decided purely by the orientation of earth's rotation axis and/or the axis of its revolution around the sun? It seems yet more curious when we consider the other anisotropies, e.g., an alignment of the four normals to the quadrupole and octopole planes in the CMBR with the cosmological dipole and the equinoxes. Then there is the other recently reported large dipole anisotropy in the NVSS radio source distribution differing in magnitude from the CMBR dipole by a factor of four, and therefore not explained as due to the peculiar motion of the Solar system, yet aligned with the CMBR

  2. Night sky a falcon field guide

    CERN Document Server

    Nigro, Nicholas

    2012-01-01

    Night Sky: A Falcon Field Guide covers both summer and winter constellations, planets, and stars found in the northern hemisphere. Conveniently sized to fit in a pocket and featuring detailed photographs, this informative guide makes it easy to identify objects in the night sky even from one's own backyard. From information on optimal weather conditions, preferred viewing locations, and how to use key tools of the trade, this handbook will help you adeptly navigate to and fro the vast and dynamic nighttime skies, and you'll fast recognize that the night sky's the limit.

  3. Short Timescale Variability In The Faint Sky Variability Survey

    NARCIS (Netherlands)

    Morales-Rueda, L.; Groot, P.J.; Augusteijn, T.; Nelemans, G.A.; Vreeswijk, P.M.; Besselaar, E.J.M. van den

    2006-01-01

    We present the V band variability analysis of the point sources in the Faint Sky Variability Survey on time scales from 24 minutes to tens of days. We find that about one percent of the point sources down to V = 24 are variables. We discuss the variability detection probabilities for each field

  4. Short timescale variability in the faint sky variability survey

    NARCIS (Netherlands)

    Morales-Rueda, L.; Groot, P.J.; Augusteijn, T.; Nelemans, G.A.; Vreeswijk, P.M.; Besselaar, E.J.M. van den

    2006-01-01

    We present the V-band variability analysis of the Faint Sky Variability Survey (FSVS). The FSVS combines colour and time variability information, from timescales of 24 minutes to tens of days, down to V = 24. We find that �1% of all point sources are variable along the main sequence reaching �3.5%

  5. Distribution of hourly variability index of sky clearness | Madhlopa ...

    African Journals Online (AJOL)

    Clouds affect the values of insolation for solar technology and other applications. To detect the presence of variability in the sky clearness, an hourly variability index ( 3) is calculated. The present study examined the frequency distribution of this variable as a tool for assessing the utilizability of solar radiation at a site.

  6. An efficient method for removing point sources from full-sky radio interferometric maps

    Science.gov (United States)

    Berger, Philippe; Oppermann, Niels; Pen, Ue-Li; Shaw, J. Richard

    2017-12-01

    A new generation of wide-field radio interferometers designed for 21-cm surveys is being built as drift scan instruments allowing them to observe large fractions of the sky. With large numbers of antennas and frequency channels, the enormous instantaneous data rates of these telescopes require novel, efficient, data management and analysis techniques. The m-mode formalism exploits the periodicity of such data with the sidereal day, combined with the assumption of statistical isotropy of the sky, to achieve large computational savings and render optimal analysis methods computationally tractable. We present an extension to that work that allows us to adopt a more realistic sky model and treat objects such as bright point sources. We develop a linear procedure for deconvolving maps, using a Wiener filter reconstruction technique, which simultaneously allows filtering of these unwanted components. We construct an algorithm, based on the Sherman-Morrison-Woodbury formula, to efficiently invert the data covariance matrix, as required for any optimal signal-to-noise ratio weighting. The performance of our algorithm is demonstrated using simulations of a cylindrical transit telescope.

  7. The Gamma-ray Sky with Fermi

    Science.gov (United States)

    Thompson, David

    2012-01-01

    Gamma rays reveal extreme, nonthermal conditions in the Universe. The Fermi Gamma-ray Space Telescope has been exploring the gamma-ray sky for more than four years, enabling a search for powerful transients like gamma-ray bursts, novae, solar flares, and flaring active galactic nuclei, as well as long-term studies including pulsars, binary systems, supernova remnants, and searches for predicted sources of gamma rays such as dark matter annihilation. Some results include a stringent limit on Lorentz invariance derived from a gamma-ray burst, unexpected gamma-ray variability from the Crab Nebula, a huge gamma-ray structure associated with the center of our galaxy, surprising behavior from some gamma-ray binary systems, and a possible constraint on some WIMP models for dark matter.

  8. Death of Darkness: Artificial Sky Brightness in the Anthropocene

    Science.gov (United States)

    Zender, C. S.

    2016-12-01

    Many species (including ours) need darkness to survive and thrive yet light pollution in the anthropocene has received scant attention in Earth System Models (ESMs). Anthropogenic aerosols can brighten background sky brightness and reduce the contrast between skylight and starlight. These are both aesthetic and health-related issues due to their accompanying disruption of circadian rhythms. We quantify aerosol contributions to light pollution using a single-column night sky model, NiteLite, suitable for implementation in ESMs. NiteLite accounts for physiologcal (photopic and scotopic vision, retinal diameter/age), anthropogenic (light and aerosol pollution properties), and natural (surface albedo, trace gases) effects on background brightness and threshold visibility. We find that stratospheric aerosol injection contemplated as a stop-gap measure to counter global warming would increase night-sky brightness by about 25%, and thus eliminate last pristine dark sky areas on Earth. Our results suggest that ESMs incorporate light pollution so that associated societal impacts can be better quantified and included in policy deliberations.

  9. Sky alert! when satellites fail

    CERN Document Server

    Johnson, Les

    2013-01-01

    How much do we depend on space satellites? Defense, travel, agriculture, weather forecasting, mobile phones and broadband, commerce...the list seems endless. But what would our live be like if the unimaginable happened and, by accident or design, those space assets disappeared? Sky Alert! explores what our world would be like, looking in turn at areas where the loss could have catastrophic effects. The book - demonstrates our dependence on space technology and satellites; - outlines the effect on our economy, defense, and daily lives if satellites and orbiting spacecraft were destroyed; - illustrates the danger of dead satellites, spent rocket stages, and space debris colliding with a functioning satellites; - demonstrates the threat of dramatically increased radiation levels associated with geomagnetic storms; - introduces space as a potential area of conflict between nations.

  10. Protecting Dark Skies in Chile

    Science.gov (United States)

    Smith, R. Chris; Sanhueza, Pedro; Phillips, Mark

    2018-01-01

    Current projections indicate that Chile will host approximately 70% of the astronomical collecting area on Earth by 2030, augmenting the enormous area of ALMA with that of three next-generation optical telescopes: LSST, GMTO, and E-ELT. These cutting-edge facilities represent billions of dollars of investment in the astronomical facilities hosted in Chile. The Chilean government, Chilean astronomical community, and the international observatories in Chile have recognized that these investments are threatened by light pollution, and have formed a strong collaboration to work at managing the threats. We will provide an update on the work being done in Chile, ranging from training municipalities about new lighting regulations to exploring international recognition of the dark sky sites of Northern Chile.

  11. Blue Skies, Coffee Creamer, and Rayleigh Scattering

    Science.gov (United States)

    Liebl, Michael

    2010-01-01

    The first physical explanation of Earths blue sky was fashioned in 1871 by Lord Rayleigh. Many discussions of Rayleigh scattering and approaches to studying it both in and out of the classroom are available. Rayleigh scattering accounts for the blue color of the sky and the orange/red color of the Sun near sunset and sunrise, and a number of…

  12. Optical sky brightness at Dome A, Antarctica, from the Nigel experiment

    Science.gov (United States)

    Sims, Geoff; Ashley, Michael C. B.; Cui, Xiangqun; Everett, Jon R.; Feng, Longlong; Gong, Xuefei; Hengst, Shane; Hu, Zhongwen; Lawrence, Jon S.; Luong-van, Daniel M.; Shang, Zhaohui; Storey, John W. V.; Wang, Lifan; Yang, Huigen; Yang, Ji; Zhou, Xu; Zhu, Zhengxi

    2010-07-01

    Nigel is a fiber-fed UV/visible grating spectrograph with a thermoelectrically-cooled 256×1024 pixel CCD camera, designed to measure the twilight and night sky brightness from 300nm to 850 nm. Nigel has three pairs of fibers, each with a field-of-view with an angular diameter of 25 degrees, pointing in three fixed positions towards the sky. The bare fibers are exposed to the sky with no additional optics. The instrument was deployed at Dome A, Antarctica in January 2009 as part of the PLATO (PLATeau Observatory) robotic observatory. During the 2009 winter, Nigel made approximately six months of continuous observations of the sky, with typically 104 deadtime between exposures. The resulting spectra provide quantitative information on the sky brightness, the auroral contribution, and the water vapour content of the atmosphere. We present details of the design, construction and calibration of the Nigel spectrometer, as well some sample spectra from a preliminary analysis.

  13. Spatiotemporal change of sky polarization during the total solar eclipse on 29 March 2006 in Turkey: polarization patterns of the eclipsed sky observed by full-sky imaging polarimetry.

    Science.gov (United States)

    Sipocz, Brigitta; Hegedüs, Ramón; Kriska, György; Horváth, Gábor

    2008-12-01

    Using 180 degrees field-of-view (full-sky) imaging polarimetry, we measured the spatiotemporal change of the polarization of skylight during the total solar eclipse on 29 March 2006 in Turkey. We present our observations here on the temporal variation of the celestial patterns of the degree p and angle alpha of linear polarization of the eclipsed sky measured in the red (650 nm), green (550 nm), and blue (450 nm) parts of the spectrum. We also report on the temporal and spectral change of the positions of neutral (unpolarized, p = 0) points, and points with local minima or maxima of p of the eclipsed sky. Our results are compared with the observations performed by the same polarimetric technique during the total solar eclipse on 11 August 1999 in Hungary. Practically the same characteristics of celestial polarization were encountered during both eclipses. This shows that the observed polarization phenomena of the eclipsed sky may be general.

  14. The new world atlas of artificial night sky brightness

    Science.gov (United States)

    Falchi, Fabio; Cinzano, Pierantonio; Duriscoe, Dan; Kyba, Christopher C. M.; Elvidge, Christopher D.; Baugh, Kimberly; Portnov, Boris A.; Rybnikova, Nataliya A.; Furgoni, Riccardo

    2016-01-01

    Artificial lights raise night sky luminance, creating the most visible effect of light pollution—artificial skyglow. Despite the increasing interest among scientists in fields such as ecology, astronomy, health care, and land-use planning, light pollution lacks a current quantification of its magnitude on a global scale. To overcome this, we present the world atlas of artificial sky luminance, computed with our light pollution propagation software using new high-resolution satellite data and new precision sky brightness measurements. This atlas shows that more than 80% of the world and more than 99% of the U.S. and European populations live under light-polluted skies. The Milky Way is hidden from more than one-third of humanity, including 60% of Europeans and nearly 80% of North Americans. Moreover, 23% of the world’s land surfaces between 75°N and 60°S, 88% of Europe, and almost half of the United States experience light-polluted nights. PMID:27386582

  15. BIG SKY CARBON SEQUESTRATION PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Susan M. Capalbo

    2005-01-31

    The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I fall into four areas: evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; development of GIS-based reporting framework that links with national networks; designing an integrated suite of monitoring, measuring, and verification technologies and assessment frameworks; and initiating a comprehensive education and outreach program. The groundwork is in place to provide an assessment of storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that would complement the ongoing DOE research. Efforts are underway to showcase the architecture of the GIS framework and initial results for sources and sinks. The region has a diverse array of geological formations that could provide storage options for carbon in one or more of its three states. Likewise, initial estimates of terrestrial sinks indicate a vast potential for increasing and maintaining soil C on forested, agricultural, and reclaimed lands. Both options include the potential for offsetting economic benefits to industry and society. Steps have been taken to assure that the GIS-based framework is consistent among types of sinks within the Big Sky Partnership area and with the efforts of other western DOE partnerships. The Partnership recognizes the critical importance of measurement, monitoring, and verification technologies to support not only carbon trading but all policies and programs that DOE and other agencies may want to pursue in support of GHG mitigation. The efforts in developing and implementing MMV technologies for geological sequestration reflect this concern. Research is

  16. Exploring Milkyway Halo Substructures with Large-Area Sky Surveys

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ting [Texas A & M Univ., College Station, TX (United States)

    2016-01-01

    Over the last two decades, our understanding of the Milky Way has been improved thanks to large data sets arising from large-area digital sky surveys. The stellar halo is now known to be inhabited by a variety of spatial and kinematic stellar substructures, including stellar streams and stellar clouds, all of which are predicted by hierarchical Lambda Cold Dark Matter models of galaxy formation. In this dissertation, we first present the analysis of spectroscopic observations of individual stars from the two candidate structures discovered using an M-giant catalog from the Two Micron All-Sky Survey. The follow-up observations show that one of the candidates is a genuine structure which might be associated with the Galactic Anticenter Stellar Structure, while the other one is a false detection due to the systematic photometric errors in the survey or dust extinction in low Galactic latitudes. We then presented the discovery of an excess of main sequence turn-off stars in the direction of the constellations of Eridanus and Phoenix from the first-year data of the Dark Energy Survey (DES) – a five-year, 5,000 deg2 optical imaging survey in the Southern Hemisphere. The Eridanus-Phoenix (EriPhe) overdensity is centered around l ~ 285° and b ~ -60° and the Poisson significance of the detection is at least 9σ. The EriPhe overdensity has a cloud-like morphology and the extent is at least ~ 4 kpc by ~ 3 kpc in projection, with a heliocentric distance of about d ~ 16 kpc. The EriPhe overdensity is morphologically similar to the previously-discovered Virgo overdensity and Hercules-Aquila cloud. These three overdensities lie along a polar plane separated by ~ 120° and may share a common origin. In addition to the scientific discoveries, we also present the work to improve the photometric calibration in DES using auxiliary calibration systems, since the photometric errors can cause false detection in first the halo substructure. We present a detailed description of the two

  17. NASA Science Engagement Through "Sky Art"

    Science.gov (United States)

    Bethea, K. L.; Damadeo, K.

    2013-12-01

    Sky Art is a NASA-funded online community where the public can share in the beauty of nature and the science behind it. At the center of Sky Art is a gallery of amateur sky photos submitted by users that are related to NASA Earth science mission research areas. Through their submissions, amateur photographers from around the world are engaged in the process of making observations, or taking pictures, of the sky just like many NASA science instruments. By submitting their pictures and engaging in the online community discussions and interactions with NASA scientists, users make the connection between the beauty of nature and atmospheric science. Sky Art is a gateway for interaction and information aimed at drawing excitement and interest in atmospheric phenomena including sunrises, sunsets, moonrises, moonsets, and aerosols, each of which correlates to a NASA science mission. Educating the public on atmospheric science topics in an informal way is a central goal of Sky Art. NASA science is included in the community through interaction from scientists, NASA images, and blog posts on science concepts derived from the images. Additionally, the website connects educators through the formal education pathway where science concepts are taught through activities and lessons that align with national learning standards. Sky Art was conceived as part of the Education and Public Outreach program of the SAGE III on ISS mission. There are currently three other NASA mission involved with Sky Art: CALIPSO, GPM, and CLARREO. This paper will discuss the process of developing the Sky Art online website, the challenges of growing a community of users, as well as the use of social media and mobile applications in science outreach and education.

  18. New science catalogs of UV sources from the GALEX sky surveys, matched to optical-IR surveys. Related science tools, models, and first results on the characterization of evolved Galactic stellar populations.

    Science.gov (United States)

    Bianchi, Luciana; Shiao, Bernie; Thilker, David; Barr, Robert; Girardi, Leo

    2018-01-01

    GUVcat is a new, expanded and improved catalog of Ultraviolet (UV) sources from the GALEX surveys (Bianchi et al. 2017, ApJ Suppl, 230, 24; arXiv:1704.05903). It contains 83million unique sources measured in FUV and NUV (duplicate measurements and rim artifacts removed) at AIS depth (about FUV colors to classify sources by astrophysical class, and to characterize classes of stellar sources to which UV data are uniquely sensitive, such as hot white dwarfs (WD), including elusive types of binaries. We compared the content of Galactic sources with Milky Way models, computed with different prescriptions. We also matched GUVcat with the first Gaia source and Gaia TGAS releases, which add precise position and G-band photometry for the bright sources, and direct distance measurements for a few very bright sources. GALEX spectra are also available and included in the analysis. Follow-up observations with HST are ongoing for an exploratory subsample.The source catalogs and related tools are available from the uvsky web site http://dolomiti.pha.jhu.edu/uvsky/#GUVcat . GUVcat_AIS is also available from MAST casjobs and soon from Vizier. A useful tool for calculating the effective area coverage of GUVcat, and of the matched catalogs, in user-chosen regions of the sky, is also available at the above url.Acknowledgements: Partial support for this work was provided by NASA grants: NNX16AF40G, NNX14AF88G, HST-GO-14119.001

  19. A Regional, Multi-Stakeholder Collaboration for Dark-Sky Protection in Flagstaff, Arizona

    Science.gov (United States)

    Hall, Jeffrey C.

    2018-01-01

    Flagstaff, Arizona is home to almost $200M in astronomical assets, including Lowell Observatory's 4.3-meter Discovery Channel Telescope and the Navy Precision Optical Interferometer, a partnership of Lowell, the U. S. Naval Observatory, and the Naval Research Laboratory. The City of Flagstaff and surrounding Coconino County have comprehensive and effective dark-sky ordinances, but continued regional growth has the potential to degrade the area's dark skies to a level at which observatory missions could be compromised. As a result, a wide array of stakeholders (the observatories, the City, the County, local dark-sky advocates, the business and tourism communities, the national parks and monuments, the Navajo Nation, the U. S. Navy, and others) have engaged in three complementary efforts to ensure that Flagstaff and Coconino County protect the area's dark skies while meeting the needs of the various communities and providing for continued growth and development. In this poster, I will present the status of Flagstaff's conversion to LED outdoor lighting, the Mission Compatibility Study carried out by the Navy to evaluate the dark-sky effects of buildout in Flagstaff, and the Joint Land Use Study (JLUS) presently underway among all the aforementioned stakeholders. Taken in sum, the efforts represent a comprehensive and constructive approach to dark-sky preservation region-wide, and they show what can be achieved when a culture of dark-sky protection is present and deliberate efforts are undertaken to maintain it for decades to come.

  20. Sky dancer: an intermittent system

    Science.gov (United States)

    Cros, Anne; Rodríguez Romero, Jesse Alexander; Damián Díaz Andrade, Oscar

    2009-11-01

    Sky dancers attract people sight to make advertising. What is the origin of those large vertical tubes fluctuations above an air blower? This study complements the previous one [1] about the system analysis from a dynamical system point of view. As a difference from the ``garden hose-instability'' [2], the tube shape has got ``break points''. Those ``break points'' separate the air-filled bottom tube portion from its deflated top portion. We record the tube dynamics with a high-speed videocamera simultaneously that we measure the pressure at the air blower exit. The intermittent pressure evolution displays picks when the tube fluctuates. We compare those overpressure values with the ones that appears in a rigid tube whose exit is partially obstructed. [1] F. Castillo Flores & A. Cros ``Transition to chaos of a vertical collapsible tube conveying air flow'' J. Phys.: Conf. Ser. 166, 012017 (2009). [2] A. S. Greenwald & J. Dungundji ``Static and dynamic instabilities of a propellant line'' MIT Aeroelastic and Structures Research Lab, AFOSR Sci. Report: AFOSR 67-1395 (1967).

  1. Big Sky Carbon Sequestration Partnership

    Energy Technology Data Exchange (ETDEWEB)

    Susan Capalbo

    2005-12-31

    The Big Sky Carbon Sequestration Partnership, led by Montana State University, is comprised of research institutions, public entities and private sectors organizations, and the Confederated Salish and Kootenai Tribes and the Nez Perce Tribe. Efforts under this Partnership in Phase I are organized into four areas: (1) Evaluation of sources and carbon sequestration sinks that will be used to determine the location of pilot demonstrations in Phase II; (2) Development of GIS-based reporting framework that links with national networks; (3) Design of an integrated suite of monitoring, measuring, and verification technologies, market-based opportunities for carbon management, and an economic/risk assessment framework; (referred to below as the Advanced Concepts component of the Phase I efforts) and (4) Initiation of a comprehensive education and outreach program. As a result of the Phase I activities, the groundwork is in place to provide an assessment of storage capabilities for CO{sub 2} utilizing the resources found in the Partnership region (both geological and terrestrial sinks), that complements the ongoing DOE research agenda in Carbon Sequestration. The geology of the Big Sky Carbon Sequestration Partnership Region is favorable for the potential sequestration of enormous volume of CO{sub 2}. The United States Geological Survey (USGS 1995) identified 10 geologic provinces and 111 plays in the region. These provinces and plays include both sedimentary rock types characteristic of oil, gas, and coal productions as well as large areas of mafic volcanic rocks. Of the 10 provinces and 111 plays, 1 province and 4 plays are located within Idaho. The remaining 9 provinces and 107 plays are dominated by sedimentary rocks and located in the states of Montana and Wyoming. The potential sequestration capacity of the 9 sedimentary provinces within the region ranges from 25,000 to almost 900,000 million metric tons of CO{sub 2}. Overall every sedimentary formation investigated

  2. Teaching Chemistry Using October Sky

    Science.gov (United States)

    Goll, James G.; Wilkinson, Lindsay J.; Snell, Dolores M.

    2009-02-01

    The first artificial satellite, Sputnik, was launched over fifty years ago, on October 4, 1957, marking the beginning of the space age. The launch of Sputnik inspired coal miners’ sons in Coalwood, West Virginia, to form a rocket research program. The story of these coal miners’ sons was told by Homer Hickham, Jr., in the book Rocket Boys: A Memoir, and later in the movie adaptation October Sky. Both the book and the movie show the importance of mentoring from a teacher, Frieda Riley, who encouraged the Rocket Boys in their endeavors. The story of the Rocket Boys can be used in science classrooms as a means to teach the scientific process and to create what is termed in both the book and movie as a body of knowledge. Several chemical principles important in the development of rocket propellant systems were depicted in the book and movie. These propellant systems are comparable to those used for the solid rocket boosters used to launch the space shuttles. The use of popular media in the classroom can engage and inspire students and teachers alike.

  3. Hunting the Southern Skies with SIMBA

    Science.gov (United States)

    2001-08-01

    PR Photo 28a/01 [Preview - JPEG: 400 x 568 pix - 61k] [Normal - JPEG: 800 x 1136 pix - 200k] Caption : This intensity-coded, false-colour SIMBA image is centered on the infrared source IRAS 17175-3544 and covers the well-known high-mass star formation complex NGC 6334 , at a distance of 5500 light-years. The southern bright source is an ultra-compact region of ionized hydrogen ("HII region") created by a star or several stars already formed. The northern bright source has not yet developed an HII region and may be a star or a cluster of stars that are presently forming. A remarkable, narrow, linear dust filament extends over the image; it was known to exist before, but the SIMBA image now shows it to a much larger extent and much more clearly. This and the following images cover an area of about 15 arcmin x 6 arcmin on the sky and have a pixel size of 8 arcsec. ESO PR Photo 28b/01 ESO PR Photo 28b/01 [Preview - JPEG: 532 x 400 pix - 52k] [Normal - JPEG: 1064 x 800 pix - 168k] Caption : This SIMBA image is centered on the object IRAS 18434-0242 . It includes many bright sources that are associated with dense cores and compact HII regions located deep inside the cloud. A much less detailed map was made several years ago with a single channel bolometer on SEST. The new SIMBA map is more extended and shows more sources. ESO PR Photo 28c/01 ESO PR Photo 28c/01 [Preview - JPEG: 400 x 505 pix - 59k] [Normal - JPEG: 800 x 1009 pix - 160k] Caption : Another SIMBA image is centered on IRAS 17271-3439 and includes an extended bright source that is associated with several compact HII regions as well as a cluster of weaker sources. Some of the recent SIMBA images are shown above; they were taken during test observations, and within a pilot survey of high-mass starforming regions . Stars form in interstellar clouds that consist of gas and dust. The denser parts of these clouds can collapse into cold and dense cores which may form stars. Often many stars are formed in clusters, at

  4. Angle of sky light polarization derived from digital images of the sky under various conditions.

    Science.gov (United States)

    Zhang, Wenjing; Cao, Yu; Zhang, Xuanzhe; Yang, Yi; Ning, Yu

    2017-01-20

    Skylight polarization is used for navigation by some birds and insects. Skylight polarization also has potential for human navigation applications. Its advantages include relative immunity from interference and the absence of error accumulation over time. However, there are presently few examples of practical applications for polarization navigation technology. The main reason is its weak robustness during cloudy weather conditions. In this paper, the real-time measurement of the sky light polarization pattern across the sky has been achieved with a wide field of view camera. The images were processed under a new reference coordinate system to clearly display the symmetrical distribution of angle of polarization with respect to the solar meridian. A new algorithm for the extraction of the image axis of symmetry is proposed, in which the real-time azimuth angle between the camera and the solar meridian is accurately calculated. Our experimental results under different weather conditions show that polarization navigation has high accuracy, is strongly robust, and performs well during fog and haze, clouds, and strong sunlight.

  5. Present status on atomic and molecular data relevant to fusion plasma diagnostics and modeling

    Energy Technology Data Exchange (ETDEWEB)

    Tawara, H. [ed.

    1997-01-01

    This issue is the collection of the paper presented status on atomic and molecular data relevant to fusion plasma diagnostics and modeling. The 10 of the presented papers are indexed individually. (J.P.N.)

  6. The GMRT 150 MHz all-sky radio survey. First alternative data release TGSS ADR1

    Science.gov (United States)

    Intema, H. T.; Jagannathan, P.; Mooley, K. P.; Frail, D. A.

    2017-02-01

    We present the first full release of a survey of the 150 MHz radio sky, observed with the Giant Metrewave Radio Telescope (GMRT) between April 2010 and March 2012 as part of the TIFR GMRT Sky Survey (TGSS) project. Aimed at producing a reliable compact source survey, our automated data reduction pipeline efficiently processed more than 2000 h of observations with minimal human interaction. Through application of innovative techniques such as image-based flagging, direction-dependent calibration of ionospheric phase errors, correcting for systematic offsets in antenna pointing, and improving the primary beam model, we created good quality images for over 95 percent of the 5336 pointings. Our data release covers 36 900 deg2 (or 3.6 π steradians) of the sky between -53° and +90° declination (Dec), which is 90 percent of the total sky. The majority of pointing images have a noise level below 5 mJy beam-1 with an approximate resolution of 25''×25'' (or 25''×25''/ cos(Dec-19°) for pointings south of 19° declination). We have produced a catalog of 0.62 Million radio sources derived from an initial, high reliability source extraction at the seven sigma level. For the bulk of the survey, the measured overall astrometric accuracy is better than two arcseconds in right ascension and declination, while the flux density accuracy is estimated at approximately ten percent. Within the scope of the TGSS alternative data release (TGSS ADR) project, the source catalog, as well as 5336 mosaic images (5°×5°) and an image cutout service, are made publicly available at the CDS as a service to the astronomical community. Next to enabling a wide range of different scientific investigations, we anticipate that these survey products will provide a solid reference for various new low-frequency radio aperture array telescopes (LOFAR, LWA, MWA, SKA-low), and can play an important role in characterizing the epoch-of-reionisation (EoR) foreground. The TGSS ADR project aims at

  7. Astronomy and civilization in the new enlightenment passions of the skies

    CERN Document Server

    Tymieniecka, Anna-Teresa

    2011-01-01

    This volume presents astronomy as the fulcrum of the sciences, giving full expression to the human passion for the skies. It illustrates how the interplay between human beings and the celestial realm has informed civilizational trends.

  8. Cloud classification using whole-sky imager data

    Energy Technology Data Exchange (ETDEWEB)

    Buch, K.A. Jr.; Sun, C.H.; Thorne, L.R. [Sandia National Labs., Livermore, CA (United States)

    1996-04-01

    Clouds are one of the most important moderators of the earth radiation budget and one of the least understood. The effect that clouds have on the reflection and absorption of solar and terrestrial radiation is strongly influenced by their shape, size, and composition. Physically accurate parameterization of clouds is necessary for any general circulation model (GCM) to yield meaningful results. The work presented here is part of a larger project that is aimed at producing realistic three-dimensional (3D) volume renderings of cloud scenes based on measured data from real cloud scenes. These renderings will provide the important shape information for parameterizing GCMs. The specific goal of the current study is to develop an algorithm that automatically classifies (by cloud type) the clouds observed in the scene. This information will assist the volume rendering program in determining the shape of the cloud. Much work has been done on cloud classification using multispectral satellite images. Most of these references use some kind of texture measure to distinguish the different cloud types and some also use topological features (such as cloud/sky connectivity or total number of clouds). A wide variety of classification methods has been used, including neural networks, various types of clustering, and thresholding. The work presented here uses binary decision trees to distinguish the different cloud types based on cloud features vectors.

  9. Estimation of global illuminance for clear skies at Madrid

    Energy Technology Data Exchange (ETDEWEB)

    Robledo, L. [Departamento de Sistemas Inteligentes Aplicados, E.U. Informatica, Universidad Politecnica de Madrid, Madrid (Spain); Soler, A. [Departamento de Fisica e Instalaciones, ETSAM, Madrid (Spain)

    2000-07-01

    Two elementary empirical models for the dependence of global illuminance on solar elevation for clear skies are provided. The models are developed from hourly data obtained from 1 year data collected at the International Daylight Measurement Programme (IDMP) general class station at the Escuela Tecnica Superior de Arquitectura in Madrid (ETSAM), and are statistically assessed with data obtained during another period of 6 months. Values of the mean bias deviation (MBD) and root mean square deviation (RMSD) of respectively less than 5% and 7% of the average illuminance measured were obtained. The qualitative dependence of global illuminance on solar elevation, common to that found by other researchers for other locations is justified, and found to be different to that given by Vazquez and Bernabeu [D. Vazquez, E. Bernabeu, Quantitative estimation of clear sky light in Madrid, Energy and Buildings, 26 (1997) 331] using data obtained at a site which is in close proximity to our station. (author)

  10. The SkyMapper Transient Survey

    Science.gov (United States)

    Scalzo, R. A.; Yuan, F.; Childress, M. J.; Möller, A.; Schmidt, B. P.; Tucker, B. E.; Zhang, B. R.; Onken, C. A.; Wolf, C.; Astier, P.; Betoule, M.; Regnault, N.

    2017-07-01

    The SkyMapper 1.3 m telescope at Siding Spring Observatory has now begun regular operations. Alongside the Southern Sky Survey, a comprehensive digital survey of the entire southern sky, SkyMapper will carry out a search for supernovae and other transients. The search strategy, covering a total footprint area of 2 000 deg2 with a cadence of ⩽5 d, is optimised for discovery and follow-up of low-redshift type Ia supernovae to constrain cosmic expansion and peculiar velocities. We describe the search operations and infrastructure, including a parallelised software pipeline to discover variable objects in difference imaging; simulations of the performance of the survey over its lifetime; public access to discovered transients; and some first results from the Science Verification data.

  11. Aladin Lite: Lightweight sky atlas for browsers

    Science.gov (United States)

    Boch, Thomas

    2014-02-01

    Aladin Lite is a lightweight version of the Aladin tool, running in the browser and geared towards simple visualization of a sky region. It allows visualization of image surveys (JPEG multi-resolution HEALPix all-sky surveys) and permits superimposing tabular (VOTable) and footprints (STC-S) data. Aladin Lite is powered by HTML5 canvas technology and is easily embeddable on any web page and can also be controlled through a Javacript API.

  12. The Mythology of the Night Sky

    Science.gov (United States)

    Falkner, David E.

    The word "planet" comes from the Latin word planeta and the Greek word planes, which means "wanderer." When the ancient Greeks studied the night sky they noticed that most of the stars remained in the same position relative to all the other stars, but a few stars seem to move in the sky from day to day, week to week, and month to month. The Greeks called these rogue stars "wanderers" because they wandered through the starry background.

  13. Stability of FORS2 Sky Flats

    Science.gov (United States)

    Boffin, Henri M. J.; Dobrzycka, D.; Hummel, C.; Moehler, S.; Smoker, J.; Anderson, J.; Dias, B.

    2017-09-01

    "The FORS2 calibration plan previously had a validity for imaging sky flatfields of four days. This placed some stress on the observers, especially during periods of bad weather. We therefore decided to analyse a series of flats to check if it was possible to extend this validity range, and if yes, to what level. The analysis allowed us to change the FORS2 calibration plan, increasing the validity of sky flats from four to 14 days."

  14. Robust Synchronization Models for Presentation System Using SMIL-Driven Approach

    Science.gov (United States)

    Asnawi, Rustam; Ahmad, Wan Fatimah Wan; Rambli, Dayang Rohaya Awang

    2013-01-01

    Current common Presentation System (PS) models are slide based oriented and lack synchronization analysis either with temporal or spatial constraints. Such models, in fact, tend to lead to synchronization problems, particularly on parallel synchronization with spatial constraints between multimedia element presentations. However, parallel…

  15. The Next Generation Sky Survey and the Quest for Cooler Brown Dwarfs

    OpenAIRE

    Kirkpatrick, J. Davy

    2002-01-01

    The Next Generation Sky Survey (NGSS) is a proposed NASA MIDEX mission to map the entire sky in four infrared bandpasses - 3.5, 4.7, 12, and 23 um. The seven-month mission will use a 50-cm telescope and four-channel imager to survey the sky from a circular orbit above the Earth. Expected sensitivities will be half a million times that of COBE/DIRBE at 3.5 and 4.7 um and a thousand times that of IRAS at 12 and 23 um. NGSS will be particularly sensitive to brown dwarfs cooler than those present...

  16. Receptive fields of locust brain neurons are matched to polarization patterns of the sky.

    Science.gov (United States)

    Bech, Miklós; Homberg, Uwe; Pfeiffer, Keram

    2014-09-22

    Many animals, including insects, are able to use celestial cues as a reference for spatial orientation and long-distance navigation [1]. In addition to direct sunlight, the chromatic gradient of the sky and its polarization pattern are suited to serve as orientation cues [2-5]. Atmospheric scattering of sunlight causes a regular pattern of E vectors in the sky, which are arranged along concentric circles around the sun [5, 6]. Although certain insects rely predominantly on sky polarization for spatial orientation [7], it has been argued that detection of celestial E vector orientation may not suffice to differentiate between solar and antisolar directions [8, 9]. We show here that polarization-sensitive (POL) neurons in the brain of the desert locust Schistocerca gregaria can overcome this ambiguity. Extracellular recordings from POL units in the central complex and lateral accessory lobes revealed E vector tunings arranged in concentric circles within large receptive fields, matching the sky polarization pattern at certain solar positions. Modeling of neuronal responses under an idealized sky polarization pattern (Rayleigh sky) suggests that these "matched filter" properties allow locusts to unambiguously determine the solar azimuth by relying solely on the sky polarization pattern for compass navigation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. A physiological production model for cocoa (Theobroma cacao): model presentation validation and application

    NARCIS (Netherlands)

    Zuidema, P.A.; Leffelaar, P.A.; Gerritsma, W.; Mommer, L.; Anten, N.P.R.

    2005-01-01

    In spite of the economic importance and extensive agronomic literature on cocoa, no physiological production model has been developed for cocoa so far. Such a model would be very useful to compare yields in different climates and cropping systems, and to set the agenda for future agronomic research.

  18. Educating for the Preservation of Dark Skies

    Science.gov (United States)

    Preston, Sandra Lee; Cianciolo, Frank; Wetzel, Marc; Finkelstein, Keely; Wren, William; Nance, Craig

    2015-08-01

    The stars at night really are big and bright deep in the heart of Texas at the McDonald Observatory near Fort Davis, Texas. Each year 80,000 visitors from all over the world make the pilgrimage to the Observatory to attend one of the three-times-a-week star parties. Many experience, for the first time, the humbling, splendor of a truly dark night sky. Over the last several years, the Observatory has experienced dramatic increases in visitation demonstrating the public’s appetite for science education, in general, and interest in the night sky, in particular. This increasing interest in astronomy is, ironically, occurring at a time when most of humanity’s skies are becoming increasingly light-polluted frustrating this natural interest. Dark skies and knowledgeable education and outreach staff are an important resource in maintaining the public’s interest in astronomy, support for astronomical research, and local tourism.This year Observatory educators were inspired by the observance of the International Year of Light to promote healthy outdoor lighting through its popular Astronomy Day distance learning program. This program reaches tens of thousands of K-12 students in Texas and other states with a message of how they can take action to preserve dark skies. As well, more than a thousand Boy Scouts visiting during the summer months receive a special program, which includes activities focusing on good lighting practices, thereby earning them credits toward an astronomy badge.The Observatory also offers a half-a-dozen K-12 teacher professional development workshops onsite each year, which provide about 90 teachers with dark skies information, best-practice lighting demonstrations, and red flashlights. Multi-year workshops for National Park and State of Texas Parks personnel are offered on dark sky preservation and sky interpretation at McDonald and a Dark Skies fund for retrofitting lights in the surrounding area has been established. The Observatory also uses

  19. Improved Estimates of Clear Sky Longwave Flux and Application to the Tropical Greenhouse Effect

    Science.gov (United States)

    Collins, W. D.

    1997-01-01

    The first objective of this investigation is to eliminate the clear-sky offset introduced by the scene-identification procedures developed for the Earth Radiation Budget Experiment (ERBE). Estimates of this systematic bias range from 10 to as high as 30 W/sq m. The initial version of the ScaRaB data is being processed with the original ERBE algorithm. Since the ERBE procedure for scene identification is based upon zonal flux averages, clear scenes with longwave emission well below the zonal mean value are mistakenly classified as cloudy. The erroneous classification is more frequent in regions with deep convection and enhanced mid- and upper-tropospheric humidity. We will develop scene identification parameters with zonal and/or time dependence to reduce or eliminate the bias in the clear- sky data. The modified scene identification procedure could be used for the ScaRaB-specific version of the Earth-radiation products. The second objective is to investigate changes in the clear-sky Outgoing Longwave Radiation (OLR) associated with decadal variations in the tropical and subtropical climate. There is considerable evidence for a shift in the climate state starting in approximately 1977. The shift is accompanied by higher SSTs in the equatorial Pacific, increased tropical convection, and higher values of atmospheric humidity. Other evidence indicates that the humidity in the tropical troposphere has been steadily increasing over the last 30 years. It is not known whether the atmospheric greenhouse effect has increased during this period in response to these changes in SST and precipitable water. We will investigate the decadal-scale fluctuations in the greenhouse effect using Nimbus-7, ERBE, and ScaRaB measurements spaning 1979 to the present. The data from the different satellites will be intercalibrated by comparison with model calculations based upon ship radiosonde observations. The fluxes calculated from the radiation model will also be used for validation of the

  20. Reconstructing daily clear-sky land surface temperature for cloudy regions from MODIS data

    Science.gov (United States)

    Sun, Liang; Chen, Zhongxin; Gao, Feng; Anderson, Martha; Song, Lisheng; Wang, Limin; Hu, Bo; Yang, Yun

    2017-08-01

    Land surface temperature (LST) is a critical parameter in environmental studies and resource management. The MODIS LST data product has been widely used in various studies, such as drought monitoring, evapotranspiration mapping, soil moisture estimation and forest fire detection. However, cloud contamination affects thermal band observations and will lead to inconsistent LST results. In this study, we present a new Remotely Sensed DAily land Surface Temperature reconstruction (RSDAST) model that recovers clear sky LST for pixels covered by cloud using only clear-sky neighboring pixels from nearby dates. The reconstructed LST was validated using the original LST pixels. Model shows high accuracy for reconstructing one masked pixel with R2 of 0.995, bias of -0.02 K and RMSE of 0.51 K. Extended spatial reconstruction results show a better accuracy for flat areas with R2 of 0.72‒0.89, bias of -0.02-0.21 K, and RMSE of 0.92-1.16 K, and for mountain areas with R2 of 0.81-0.89, bias of -0.35-1.52 K, and RMSE of 1.42‒2.24 K. The reconstructed areas show spatial and temporal patterns that are consistent with the clear neighbor areas. In the reconstructed LST and NDVI triangle feature space which is controlled by soil moisture, LST values distributed reasonably and correspond well to the real soil moisture conditions. Our approach shows great potential for reconstructing clear sky LST under cloudy conditions and provides consistent daily LST which are critical for daily drought monitoring.

  1. Aquarius Whole Range Calibration: Celestial Sky, Ocean, and Land Targets

    Science.gov (United States)

    Dinnat, Emmanuel P.; Le Vine, David M.; Bindlish, Rajat; Piepmeier, Jeffrey R.; Brown, Shannon T.

    2014-01-01

    Aquarius is a spaceborne instrument that uses L-band radiometers to monitor sea surface salinity globally. Other applications of its data over land and the cryosphere are being developed. Combining its measurements with existing and upcoming L-band sensors will allow for long term studies. For that purpose, the radiometers calibration is critical. Aquarius measurements are currently calibrated over the oceans. They have been found too cold at the low end (celestial sky) of the brightness temperature scale, and too warm at the warm end (land and ice). We assess the impact of the antenna pattern model on the biases and propose a correction. We re-calibrate Aquarius measurements using the corrected antenna pattern and measurements over the Sky and oceans. The performances of the new calibration are evaluated using measurements over well instrument land sites.

  2. An investigation of atmospheric turbidity of Thai sky

    Energy Technology Data Exchange (ETDEWEB)

    Chaiwiwatworakul, P.; Chirarattananon, S. [Energy Programme, Asian Institute of Technology, Klong Luang, Pathum Thani (Thailand)

    2004-07-01

    An investigation of atmospheric turbidity has been undertaken for tropical Thai sky. Values of turbidity indices, namely, Linke factor (T{sub L}), Angstrom coefficient ({beta}) and illuminance turbidity factor (T{sub il}) are derived directly from measurements taken by pyrheliometer, Volz sun photometer and beam illuminance meter. Monthly mean values and frequency of occurrence of the value of each turbidity index are used to characterize variations of atmospheric turbidity. Simple polynomial equations are developed for computing values of Linke factor and illuminance turbidity factor as functions of solar altitude angle. Using the values of Linke factor and illuminance turbidity factor obtained from the models developed, values of beam normal irradiance and illuminance can be calculated accurately under clear sky conditions. Values of daylight illuminance are useful for daylighting application that contributes to energy conservation for buildings. Knowledge of the size of beam normal irradiance is useful for calculation of cooling load in air-conditioning buildings in tropical climate. (author)

  3. Dark Skies are a Universal Resource: IYA Programs on Dark Skies Awareness

    Science.gov (United States)

    Walker, Constance E.; Bueter, C.; Pompea, S. M.; Berglund, K.; Mann, T.; Gay, P.; Crelin, B.; Collins, D.; Sparks, R.

    2008-05-01

    The loss of a dark night sky as a natural resource is a growing concern. It impacts not only astronomical research, but also health, ecology, safety, economics and energy conservation. Because of its relevance, "Dark Skies” is a theme of the US Node for the International Year of Astronomy (IYA). Its goal is to raise public awareness of the impact of artificial lighting on local environments by getting people involved in a variety of dark skies-related programs. To reach this goal, the ASP session will immerse participants in hands-on, minds-on activities, events and resources on dark skies awareness. These include a planetarium show on DVD, podcasting, social networking, a digital photography contest, The Great Switch Out, Earth Hour, National Dark Skies Week, a traveling exhibit, a 6-minute video tutorial, Dark Skies Teaching Sites, Astronomy Nights in the (National) Parks, Sidewalk Astronomy Nights, and unaided-eye and digital-meter star counting programs like GLOBE at Night. The ASP "Dark Skies” session is offered to provide IYA dark skies-related programs to a variety of attendees. Participants include professional or amateur astronomers, education and public outreach professionals, science center/museum/planetarium staff and educators who want to lead activities involving dark skies awareness in conjunction with IYA. During the session, each participant will be given a package of educational materials on the various dark skies programs. We will provide the "know-how” and the means for session attendees to become community leaders in promoting these dark skies programs as public events at their home institutions during IYA. Participants will be able to jump-start their education programs through the use of well-developed instructional materials and kits sent later if they commit to leading IYA dark skies activities. For more information about the IYA Dark Skies theme, visit http://astronomy2009.us/darkskies/.

  4. [The backgroud sky subtraction around [OIII] line in LAMOST QSO spectra].

    Science.gov (United States)

    Shi, Zhi-Xin; Comte, Georges; Luo, A-Li; Tu, Liang-Ping; Zhao, Yong-Heng; Wu, Fu-Chao

    2014-11-01

    At present, most sky-subtraction methods focus on the full spectrum, not the particular location, especially for the backgroud sky around [OIII] line which is very important to low redshift quasars. A new method to precisely subtract sky lines in local region is proposed in the present paper, which sloves the problem that the width of Hβ-[OIII] line is effected by the backgroud sky subtraction. The exprimental results show that, for different redshift quasars, the spectral quality has been significantly improved using our method relative to the original batch program by LAMOST. It provides a complementary solution for the small part of LAMOST spectra which are not well handled by LAMOST 2D pipeline. Meanwhile, This method has been used in searching for candidates of double-peaked Active Galactic Nuclei.

  5. Dark Skies are a Universal Resource: Programs Planned for the International Year of Astronomy

    Science.gov (United States)

    Walker, Constance E.; US IYA Dark Skies Working Group

    2008-05-01

    The dark night sky is a natural resource that is being lost by much of the world's population. This loss is a growing, serious issue that impacts not only astronomical research, but also human health, ecology, safety, economics and energy conservation. One of the themes of the US Node targeted for the International Year of Astronomy (IYA) is "Dark Skies are a Universal Resource". The goal is to raise public awareness of the impact of artificial lighting on local environments by getting people involved locally in a variety of dark skies-related events. To reach this goal, activities are being developed that: 1) Teach about dark skies using new technology (e.g., an activity-based planetarium show on DVD, podcasting, social networking) 2) Provide thematic events on light pollution at star parties and observatory open houses (Dark Skies Teaching Sites, Astronomy Nights in the (National) Parks, Sidewalk Astronomy Nights) 3) Organize events in the arts (e.g., a photography contest) 4) Involve citizen-scientists in unaided-eye and digital-meter star counting programs (e.g., GLOBE at Night, "How Many Stars?” and the Great World Wide Star Count) and 5) Raise awareness about the link between light pollution and public health, economic issues, ecological consequences, energy conservation, safety and security (e.g., The Great Switch Out, Earth Hour, National Dark Skies Week, traveling exhibits and a 6-minute video tutorial on lighting issues). To deliver these programs, strategic networks have been established with the ASP's Night Sky Network's astronomy clubs, Astronomy from the Ground Up's science and nature centers and the Project and Family ASTRO programs, as well as the International Dark-Sky Association, GLOBE and the Astronomical League, among others. The poster presentation will outline the activities being developed, the plans for funding, implementation, marketing and the connections to the global cornerstone IYA project, "Dark Skies Awareness".

  6. Mira Soars Through the Sky

    Science.gov (United States)

    2007-01-01

    [figure removed for brevity, see original site] [figure removed for brevity, see original site] Figure 1Figure 2 New ultraviolet images from NASA's Galaxy Evolution Explorer shows a speeding star that is leaving an enormous trail of 'seeds' for new solar systems. The star, named Mira (pronounced my-rah) after the latin word for 'wonderful,' is shedding material that will be recycled into new stars, planets and possibly even life as it hurls through our galaxy. In figure 1, the upper panel shows Mira's full, comet-like tail as seen only in shorter, or 'far' ultraviolet wavelengths, while the lower panel is a combined view showing both far and longer, or 'near' ultraviolet wavelengths. The close-up picture at bottom gives a better look at Mira itself, which appears as a pinkish dot, and is moving from left to right in this view. Shed material appears in light blue. The dots in the picture are stars and distant galaxies. The large blue dot on the left side of the upper panel, and the large yellow dot in the lower panel, are both stars that are closer to us than Mira. The Galaxy Evolution Explorer discovered the strange tail during part of its routine survey of the entire sky at ultraviolet wavelengths. When astronomers first saw the picture, they were shocked because Mira has been studied for over 400 years yet nothing like this has ever been documented before. Mira's comet-like tail stretches a startling 13 light-years across the sky. For comparison, the nearest star to our sun, Proxima Centauri, is only about 4 light-years away. Mira's tail also tells a tale of its history -- the material making it up has been slowly blown off over time, with the oldest material at the end of the tail being released about 30,000 years ago (figure 2). Mira is a highly evolved, 'red giant' star near the end of its life. Technically, it is called an asymptotic giant branch star. It is red in color and bloated; for example, if a red giant were to replace our sun, it would engulf

  7. From Sky to Archive: Long Term Management of Sky Survey Data

    Science.gov (United States)

    Darch, Peter T.; Sands, Ashley E.; Borgman, Christine; Golshan, Milena S.; Traweek, Sharon

    2017-01-01

    Sky survey data may remain scientifically valuable long beyond the end of a survey’s operational period, both for continuing inquiry and for calibrating and testing instruments for subsequent generations of surveys. Astronomy infrastructure has many stakeholders, including those concerned with data management. Research libraries are increasingly partnering with scholars to sustain access to data.The Sloan Digital Sky Survey (SDSS) was among the first major scientific projects to partner with libraries in this way, embarking on a data transfer process with two university libraries. We report on a qualitative case study of this process.Ideally, long-term sustainability of sky survey data would be a key part of planning and construction, but rarely does this occur. Teams are under pressure to deliver a project on time and on budget that produces high-quality data during its operational period, leaving few resources available to plan long-term data management. The difficulty of planning is further compounded by the complexity of predicting circumstances and needs of the astronomy community in future decades. SDSS team members regarded libraries, long-lived institutions concerned with access to scholarship, as a potential solution to long-term data sustainability.As the SDSS data transfer was the first of this scale attempted - 160 TB of data - astronomers and library staff were faced with scoping the range of activities involved. They spent two years planning this five-year process. While successful overall as demonstration projects, the libraries encountered many obstacles. We found all parties experienced difficulty in articulating their notions of “scientific data,” “archiving,” “serving,” and “providing access” to the datasets. Activities and interpretations of the data transfer process varied by institutional motivations for participation and by available infrastructure. We conclude several, rather than a single, “library solutions” for long

  8. Hermite scatterers in an ultraviolet sky

    Science.gov (United States)

    Parker, Kevin J.

    2017-12-01

    The scattering from spherical inhomogeneities has been a major historical topic in acoustics, optics, and electromagnetics and the phenomenon shapes our perception of the world including the blue sky. The long wavelength limit of ;Rayleigh scattering; is characterized by intensity proportional to k4 (or λ-4) where k is the wavenumber and λ is the wavelength. With the advance of nanotechnology, it is possible to produce scatterers that are inhomogeneous with material properties that are functions of radius r, such as concentric shells. We demonstrate that with proper choice of material properties linked to the Hermite polynomials in r, scatterers can have long wavelength scattering behavior of higher powers: k8, k16, and higher. These ;Hermite scatterers; could be useful in providing unique signatures (or colors) to regions where they are present. If suspended in air under white light, the back-scattered spectrum would be shifted from blue towards violet and then ultraviolet as the higher order Hermite scatterers were illuminated.

  9. Dark Skies, Bright Kids Year 9

    Science.gov (United States)

    Burkhardt, Andrew Michael; Mathews, Allison M.; Johnson, Kelsey E.; Avilez, Ian; Beale, Luca; Bittle, Lauren E.; Bordenave, David; Finn, Molly; Firebaugh, Ariel; Hancock, Danielle; Hughes, Paul; Rochford Hayes, Christian; Lewis, Hannah; Linden, Sean; Liss, Sandra; Liu, Mengyao; McNair, Shunlante; Murphy, Edward; Prager, Brian; Pryal, Matthew; Richardson, Whitney; Song, Yiqing; Troup, Nicholas; Villadsen, Jackie; Wenger, Trey V.; Wilson, Robert Forrest

    2018-01-01

    We present updates from the ninth year of operation of Dark Skies, Bright Kids (DSBK) including new club content, continued assessments, and our seventh annual Star Party. DSBK is an entirely volunteer-run outreach organization based out of the Department of Astronomy at the University of Virginia. Our core mission is to enhance elementary science education and literacy in Virginia through fun, hands-on activities that introduce basic Astronomy concepts. DSBK’s most fundamental program is an 8-10 week long after-school Astronomy camp at surrounding local elementary schools, where each week introduces new concepts through interactive hands-on activities. Over the past two summers, we have traveled to four rural Virginia locations to bring week-long Astronomy camps to otherwise overlooked elementary school districts. These programs aim to inspire a curiosity for science and include inquiry based activities in topics ranging from the electromagnetic spectrum to the classification and evolution of galaxies. We strive to be self-reflective in our mission to inspire scientific curiosity in the minds of underserved demographics. In this effort, we continually assess the effectiveness of each activity through feedback in student-kept journal pages and observed excitement levels. This self-reflection has initiated the development of new curriculum. In addition, differing from our normal collaboration with local elementary schools, we have found great success partnering with local youth organizations, who may better represent DSBK's target demographics and have infrastructure to support incoming outreach groups.

  10. SkyLine and SkyGas: Novel automated technologies for automatic GHG flux measurements

    Science.gov (United States)

    Ineson, Philip; Stockdale, James

    2014-05-01

    1. Concerns for the future of the Earth's climate centre around the anthropogenically-driven continuing increases in atmospheric concentrations of the major 'greenhouse gases' (GHGs) which include CO2, CH4 and N2O. A major component of the global budgets for all three of these gases is the flux between the atmosphere and terrestrial ecosystems. 2. Currently, these fluxes are poorly quantified, largely due to technical limitations associated with making these flux measurements. Whilst eddy covariance systems have greatly improved such measurements at the ecosystem scale, flux measurements at the plot scale are commonly made using labour intensive traditional 'cover box' approaches; technical limitations have frequently been a bottle-neck in producing adequate and appropriate GHG flux data necessary for making land management decisions. For example, there are almost no night time flux data for N2O fluxes, and frequently such data are only measured over bare soil patches. 3. We have been addressing the design of novel field equipment for the automation of GHG flux measurements at the chamber and plot scale and will present here some of the technical solutions we have developed. These solutions include the development of the SkyLine and SkyGas approaches which resolve many of the common problems associated with making high frequency, sufficiently replicated GHG flux measurements under field conditions. 4. Unlike most other automated systems, these technologies 'fly' a single chamber to the measurement site, rather than have multiple replicated chambers and analysers. We will present data showing how such systems can deliver high time and spatial resolution flux data, with a minimum of operator intervention and, potentially, at relatively low per plot cost. We will also show how such measurements can be extended to monitoring fluxes from freshwater features in the landscape.

  11. The night sky companion a yearly guide to sky-watching 2008-2009

    CERN Document Server

    Plotner, Tammy

    2007-01-01

    The Night Sky Companion is a comprehensive guide to what can be explored in the heavens on a nightly basis. Designed to appeal to readers at all skill levels, it provides a digest for sky watchers interested in all types of astronomical information.

  12. Estimating Heat and Mass Transfer Processes in Green Roof Systems: Current Modeling Capabilities and Limitations (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Tabares Velasco, P. C.

    2011-04-01

    This presentation discusses estimating heat and mass transfer processes in green roof systems: current modeling capabilities and limitations. Green roofs are 'specialized roofing systems that support vegetation growth on rooftops.'

  13. Lithium-Ion Battery Safety Study Using Multi-Physics Internal Short-Circuit Model (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, G-.H.; Smith, K.; Pesaran, A.

    2009-06-01

    This presentation outlines NREL's multi-physics simulation study to characterize an internal short by linking and integrating electrochemical cell, electro-thermal, and abuse reaction kinetics models.

  14. Daytime Water Detection Based on Sky Reflections

    Science.gov (United States)

    Rankin, Arturo L.; Matthies, Larry H.; Bellutta, Paolo

    2011-01-01

    Robust water detection is a critical perception requirement for unmanned ground vehicle (UGV) autonomous navigation. This is particularly true in wide-open areas where water can collect in naturally occurring terrain depressions during periods of heavy precipitation and form large water bodies. One of the properties of water useful for detecting it is that its surface acts as a horizontal mirror at large incidence angles. Water bodies can be indirectly detected by detecting reflections of the sky below the horizon in color imagery. The Jet Propulsion Laboratory (JPL) has implemented a water detector based on sky reflections that geometrically locates the pixel in the sky that is reflecting on a candidate water pixel on the ground and predicts if the ground pixel is water based on color similarity and local terrain features. This software detects water bodies in wide-open areas on cross-country terrain at mid- to far-range using imagery acquired from a forward-looking stereo pair of color cameras mounted on a terrestrial UGV. In three test sequences approaching a pond under a clear, overcast, and cloudy sky, the true positive detection rate was 100% when the UGV was beyond 7 meters of the water's leading edge and the largest false positive detection rate was 0.58%. The sky reflection based water detector has been integrated on an experimental unmanned vehicle and field tested at Ft. Indiantown Gap, PA, USA.

  15. A Prognostic Model for Development of Profound Shock among Children Presenting with Dengue Shock Syndrome.

    Directory of Open Access Journals (Sweden)

    Phung Khanh Lam

    Full Text Available To identify risk factors and develop a prediction model for the development of profound and recurrent shock amongst children presenting with dengue shock syndrome (DSS.We analyzed data from a prospective cohort of children with DSS recruited at the Paediatric Intensive Care Unit of the Hospital for Tropical Disease in Ho Chi Minh City, Vietnam. The primary endpoint was "profound DSS", defined as ≥2 recurrent shock episodes (for subjects presenting in compensated shock, or ≥1 recurrent shock episodes (for subjects presenting initially with decompensated/hypotensive shock, and/or requirement for inotropic support. Recurrent shock was evaluated as a secondary endpoint. Risk factors were pre-defined clinical and laboratory variables collected at the time of presentation with shock. Prognostic model development was based on logistic regression and compared to several alternative approaches.The analysis population included 1207 children of whom 222 (18% progressed to "profound DSS" and 433 (36% had recurrent shock. Independent risk factors for both endpoints included younger age, earlier presentation, higher pulse rate, higher temperature, higher haematocrit and, for females, worse hemodynamic status at presentation. The final prognostic model for "profound DSS" showed acceptable discrimination (AUC=0.69 for internal validation and calibration and is presented as a simple score-chart.Several risk factors for development of profound or recurrent shock among children presenting with DSS were identified. The score-chart derived from the prognostic models should improve triage and management of children presenting with DSS in dengue-endemic areas.

  16. Transferring the calibration of direct solar irradiance to diffuse-sky radiance measurements for CIMEL Sun-sky radiometers.

    Science.gov (United States)

    Li, Zhengqiang; Blarel, Luc; Podvin, Thierry; Goloub, Philippe; Buis, Jean-Pierre; Morel, Jean-Philippe

    2008-04-01

    Two types of sunphotometric measurement are considered in this study: direct-Sun irradiance and diffuse-sky radiance. Based on CIMEL CE318 Sun-sky radiometer characteristics, we introduce a gain-corrected solid angle that allows interconverting calibration coefficients of these two types of measurement, thus realizing a "vicarious" radiance calibration. The accuracy of the gain-corrected solid angle depends on the number of available historical calibration records. The method is easy to use, provided that at least one laboratory calibration has been made previously. Examples coming from three distinct CE318 versions belonging to the AERONET/PHOTONS network are presented to provide details on the vicarious calibration method and protocols. From the error propagation analysis and the comparison with laboratory results, the uncertainty of the vicarious radiance calibration is shown to be comparable with the laboratory one, e.g., 3%-5%.

  17. Bianchi I model: an alternative way to model the present-day Universe

    NARCIS (Netherlands)

    Russell, Esra; Kılınç, Can Battal; Pashaev, Oktay K.

    Although the new era of high-precision cosmology of the cosmic microwave background (CMB) radiation improves our knowledge to understand the infant as well as the present-day Universe, it also leads us to question the main assumption of the exact isotropy of the CMB. There are two pieces of

  18. Estimation of aerosol optical properties from all-sky imagers

    Science.gov (United States)

    Kazantzidis, Andreas; Tzoumanikas, Panagiotis; Salamalikis, Vasilios; Wilbert, Stefan; Prahl, Christoph

    2015-04-01

    Aerosols are one of the most important constituents in the atmosphere that affect the incoming solar radiation, either directly through absorbing and scattering processes or indirectly by changing the optical properties and lifetime of clouds. Under clear skies, aerosols become the dominant factor that affect the intensity of solar irradiance reaching the ground. It has been shown that the variability in direct normal irradiance (DNI) due to aerosols is more important than the one induced in global horizontal irradiance (GHI), while the uncertainty in its calculation is dominated by uncertainties in the aerosol optical properties. In recent years, all-sky imagers are used for the detection of cloud coverage, type and velocity in a bouquet of applications including solar irradiance resource and forecasting. However, information about the optical properties of aerosols could be derived with the same instrumentation. In this study, the aerosol optical properties are estimated with the synergetic use of all-sky images, complementary data from the Aerosol Robotic Network (AERONET) and calculations from a radiative transfer model. The area of interest is Plataforma Solar de Almería (PSA), Tabernas, Spain and data from a 5 month period are analyzed. The proposed methodology includes look-up-tables (LUTs) of diffuse sky radiance of Red (R), Green (G) and Blue (B) channels at several zenith and azimuth angles and for different atmospheric conditions (Angström α and β, single scattering albedo, precipitable water, solar zenith angle). Based on the LUTS, results from the CIMEL photometer at PSA were used to estimate the RGB radiances for the actual conditions at this site. The methodology is accompanied by a detailed evaluation of its robustness, the development and evaluation of the inversion algorithm (derive aerosol optical properties from RGB image values) and a sensitivity analysis about how the pre-mentioned atmospheric parameters affect the results.

  19. A Radiometric All-Sky Infrared Camera (RASICAM) for DES/CTIO

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Peter M.; Rogers, Howard; Schindler, Rafe H.; /SLAC

    2010-08-25

    A novel radiometric all-sky infrared camera [RASICAM] has been constructed to allow automated real-time quantitative assessment of night sky conditions for the Dark Energy Camera [DECam] located on the Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile. The camera is optimized to detect the position, motion and optical depth of thin, high (8-10km) cirrus clouds and contrails by measuring their apparent temperature above the night sky background. The camera system utilizes a novel wide-field equiresolution catadioptic mirror system that provides sky coverage of 2{pi} azimuth and 14-90{sup o} from zenith. Several new technological and design innovations allow the RASICAM system to provide unprecedented cloud detection and IR-based photometricity quantification. The design of the RASICAM system is presented.

  20. Spectrometer for Sky-Scanning Sun-Tracking Atmospheric Research (4STAR: Instrument Technology

    Directory of Open Access Journals (Sweden)

    Yohei Shinozuka

    2013-08-01

    Full Text Available The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR combines airborne sun tracking and sky scanning with diffraction spectroscopy to improve knowledge of atmospheric constituents and their links to air-pollution/climate. Direct beam hyper-spectral measurement of optical depth improves retrievals of gas constituents and determination of aerosol properties. Sky scanning enhances retrievals of aerosol type and size distribution. 4STAR measurements will tighten the closure between satellite and ground-based measurements. 4STAR incorporates a modular sun-tracking/ sky-scanning optical head with fiber optic signal transmission to rack mounted spectrometers, permitting miniaturization of the external optical head, and future detector evolution. Technical challenges include compact optical collector design, radiometric dynamic range and stability, and broad spectral coverage. Test results establishing the performance of the instrument against the full range of operational requirements are presented, along with calibration, engineering flight test, and scientific field campaign data and results.

  1. Secrets to Successful Earth and Sky Photography

    Science.gov (United States)

    Tafreshi, Babak A.

    In the absolute silence of a desert night, surrounded by an arena of celestial beauties, a gentle breeze shifts the tiny grains of sand around me. There is a patchy glow of light visible all across the eastern horizon. It is gradually ascending over the sand dunes. The glow represents billions of stars in our home galaxy rising above the horizon of our planet. I have seen such dream-like starry scenes from many locations; from the boundless dark skies of the African Sahara when the summer Milky Way was arching over giant sandstones, to the shimmering beauty of the Grand Canyon under moonlight, and the transparent skies of the Himalayas when the bright stars of winter were rising above where the highest peak on Earth (Mt. Everest) meets the sky. These are forever-engraved moments in my memory. Astrophotography is not only about recording the celestial world. It can lead you to a life of adventure and discovery (Fig. 1).

  2. Hyperspectral all-sky imaging of auroras.

    Science.gov (United States)

    Sigernes, Fred; Ivanov, Yuriy; Chernouss, Sergey; Trondsen, Trond; Roldugin, Alexey; Fedorenko, Yury; Kozelov, Boris; Kirillov, Andrey; Kornilov, Ilia; Safargaleev, Vladimir; Holmen, Silje; Dyrland, Margit; Lorentzen, Dag; Baddeley, Lisa

    2012-12-03

    A prototype auroral hyperspectral all-sky camera has been constructed and tested. It uses electro-optical tunable filters to image the night sky as a function of wavelength throughout the visible spectrum with no moving mechanical parts. The core optical system includes a new high power all-sky lens with F-number equal to f/1.1. The camera has been tested at the Kjell Henriksen Observatory (KHO) during the auroral season of 2011/2012. It detects all sub classes of aurora above ~½ of the sub visual 1kR green intensity threshold at an exposure time of only one second. Supervised classification of the hyperspectral data shows promise as a new method to process and identify auroral forms.

  3. Launch window definition for sky target experiments.

    Science.gov (United States)

    Michaud, N. H.

    1973-01-01

    This paper is a brief report on the computer program developed for the Extraterrestrial Physics Barium Ion Cloud (BIC) Project. The mathematical analysis developed for the program along with its programing characteristics are pointed out to show that this program is adaptable to similar sky target projects. Definite viewing constraints are specified so that the chosen ground tracking stations can photograph the behavior of the sky target after its release. Viewing factors include the illumination of the target by the sun, the relative elevation look angle to the target from each tracking station, the solar and lunar depression angles at each tracking station, and the total sky background brightness of the target relative to each tracking station. Numeric values are assigned to each factor through program input. The program output is flexible so that the results of the window calculations can be studied to the depth required.

  4. The red-sky enigma over Svalbard in December 2002

    Directory of Open Access Journals (Sweden)

    F. Sigernes

    2005-07-01

    Full Text Available On 6 December 2002, during winter darkness, an extraordinary event occurred in the sky, as viewed from Longyearbyen (78° N, 15° E, Svalbard, Norway. At 07:30 UT the southeast sky was surprisingly lit up in a deep red colour. The light increased in intensity and spread out across the sky, and at 10:00 UT the illumination was observed to reach the zenith. The event died out at about 12:30 UT. Spectral measurements from the Auroral Station in Adventdalen confirm that the light was scattered sunlight. Even though the Sun was between 11.8 and 14.6deg below the horizon during the event, the measured intensities of scattered light on the southern horizon from the scanning photometers coincided with the rise and setting of the Sun. Calculations of actual heights, including refraction and atmospheric screening, indicate that the event most likely was scattered solar light from a target below the horizon. This is also confirmed by the OSIRIS instrument on board the Odin satellite. The deduced height profile indicates that the scattering target is located 18–23km up in the stratosphere at a latitude close to 73–75° N, southeast of Longyearbyen. The temperatures in this region were found to be low enough for Polar Stratospheric Clouds (PSC to be formed. The target was also identified as PSC by the LIDAR systems at the Koldewey Station in Ny-Ålesund (79° N, 12° E. The event was most likely caused by solar illuminated type II Polar Stratospheric Clouds that scattered light towards Svalbard. Two types of scenarios are presented to explain how light is scattered. Keywords. Atmospheric composition and structure (Transmissions and scattering of radiation; Middle atmospherecomposition and chemistry; Instruments and techniques – History of geophysics (Atmospheric Sciences; The red-sky phenomena

  5. Object-oriented DFD models to present the functional and behavioral views

    Energy Technology Data Exchange (ETDEWEB)

    Maxted, A.

    1993-06-01

    An object-oriented methodology is presented that is based on two sets of Data Flow Diagrams (DFDs): one for the functional view, and one for the behavioral view. The functional view presents the information flow between shared objects. These objects map to the classes identified in the structural view (e.g., Information Model). The behavioral view presents the flow of information between control components and relates these components to their state models. Components appearing in multiple views provide a bridge between the views. The top-down hierarchical nature of the DFDs provide a needed overview or road map through the software system.

  6. Advanced Models and Controls for Prediction and Extension of Battery Lifetime (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Smith, K.; Wood, E.; Santhanagopalan, S.; Kim, G.; Pesaran, A.

    2014-02-01

    Predictive models of capacity and power fade must consider a multiplicity of degradation modes experienced by Li-ion batteries in the automotive environment. Lacking accurate models and tests, lifetime uncertainty must presently be absorbed by overdesign and excess warranty costs. To reduce these costs and extend life, degradation models are under development that predict lifetime more accurately and with less test data. The lifetime models provide engineering feedback for cell, pack and system designs and are being incorporated into real-time control strategies.

  7. Sky-view factor visualization for detection of archaeological remains

    Science.gov (United States)

    Kokalj, Žiga; Oštir, Krištof; Zakšek, Klemen

    2013-04-01

    Many archaeological remains are covered by sand or vegetation but it still possible to detect them by remote sensing techniques. One of them is airborne laser scanning that enables production of digital elevation models (DEM) of very high resolution (better than 1 m) with high relative elevation accuracy (centimetre level), even under forest. Thus, it has become well established in archaeological applications. However, effective interpretation of digital elevation models requires appropriate data visualization. Analytical relief shading is used in most cases. Although widely accepted, this method has two major drawbacks: identifying details in deep shades and inability to properly represent linear features lying parallel to the light beam. Several authors have tried to overcome these limitations by changing the position of the light source or by filtering. This contribution addresses the DEM visualization problem by sky-view factor, a visualization technique based on diffuse light that overcomes the directional problems of hill-shading. Sky-view factor is a parameter that describes the portion of visible sky limited by relief. It can be used as a general relief visualization technique to show relief characteristics. In particular, we show that this visualization is a very useful tool in archaeology. Applying the sky-view factor for visualization purposes gives advantages over other techniques because it reveals small (or large, depending on the scale of the observed phenomenon and consequential algorithm settings) relief features while preserving the perception of general topography. In the case study (DEM visualization of a fortified enclosure of Tonovcov grad in Slovenia) we show that for the archaeological purposes the sky-view factor is the optimal DEM visualization method. Its ability to consider the neighborhood context makes it an outstanding tool when compared to other visualization techniques. One can choose a large search radius and the most important

  8. Sky radiance at a coastline and effects of land and ocean reflectivities

    Directory of Open Access Journals (Sweden)

    A. Kreuter

    2017-12-01

    Full Text Available We present a unique case study of the spectral sky radiance distribution above a coastline. Results are shown from a measurement campaign in Italy involving three diode array spectroradiometers which are compared to 3-D model simulations from the Monte Carlo model MYSTIC. On the coast, the surrounding is split into two regions, a diffusely reflecting land surface and a water surface which features a highly anisotropic reflectance function. The reflectivities and hence the resulting radiances are a nontrivial function of solar zenith and azimuth angle and wavelength. We show that for low solar zenith angles (SZAs around noon, the higher land albedo causes the sky radiance at 20° above the horizon to increase by 50 % in the near infrared at 850 nm for viewing directions towards the land with respect to the ocean. Comparing morning and afternoon radiances highlights the effect of the ocean's sun glint at high SZA, which contributes around 10 % to the measured radiance ratios. The model simulations generally agree with the measurements to better than 10 %. We investigate the individual effects of model input parameters representing land and ocean albedo and aerosols. Different land and ocean bi-directional reflectance functions (BRDFs do not generally improve the model agreement. However, consideration of the uncertainties in the diurnal variation of aerosol optical depth can explain the remaining discrepancies between measurements and model. We further investigate the anisotropy effect of the ocean BRDF which is featured in the zenith radiances. Again, the uncertainty of the aerosol loading is dominant and obscures the modelled sun glint effect of 7 % at 650 nm. Finally, we show that the effect on the zenith radiance is restricted to a few kilometres from the coastline by model simulations along a perpendicular transect and by comparing the radiances at the coast to those measured at a site 15 km inland. Our findings are relevant to

  9. Numerical modeling of present-day stress field and deformation pattern in Anatolia

    OpenAIRE

    Dwivedi, Sunil Kumar; Hayashi, Daigoro; 林, 大五郎

    2010-01-01

    The present-day stress field in the Earth's crust is important and provides insights into mechanisms that drive plate motions. In this study, an elastic plane stress finite element modeling incorporating realistic rock parameters have been used to calculate the stress field, displacement field and deformation of the plate interactions in Anatolia. Modeled stress data for the African-Arabian-Anatolian plate interactions with fixed Eurasian platform correlate well with observed stress indicator...

  10. Night-sky brightness monitoring in Hong Kong: a city-wide light pollution assessment.

    Science.gov (United States)

    Pun, Chun Shing Jason; So, Chu Wing

    2012-04-01

    Results of the first comprehensive light pollution survey in Hong Kong are presented. The night-sky brightness was measured and monitored around the city using a portable light-sensing device called the Sky Quality Meter over a 15-month period beginning in March 2008. A total of 1,957 data sets were taken at 199 distinct locations, including urban and rural sites covering all 18 Administrative Districts of Hong Kong. The survey shows that the environmental light pollution problem in Hong Kong is severe-the urban night skies (sky brightness at 15.0 mag arcsec(- 2)) are on average ~ 100 times brighter than at the darkest rural sites (20.1 mag arcsec(- 2)), indicating that the high lighting densities in the densely populated residential and commercial areas lead to light pollution. In the worst polluted urban location studied, the night-sky at 13.2 mag arcsec(- 2) can be over 500 times brighter than the darkest sites in Hong Kong. The observed night-sky brightness is found to be affected by human factors such as land utilization and population density of the observation sites, together with meteorological and/or environmental factors. Moreover, earlier night skies (at 9:30 p.m. local time) are generally brighter than later time (at 11:30 p.m.), which can be attributed to some public and commercial lightings being turned off later at night. On the other hand, no concrete relationship between the observed sky brightness and air pollutant concentrations could be established with the limited survey sampling. Results from this survey will serve as an important database for the public to assess whether new rules and regulations are necessary to control the use of outdoor lightings in Hong Kong.

  11. Modelling of present and future hydrology and solute transport at Forsmark. SR-Site Biosphere

    Energy Technology Data Exchange (ETDEWEB)

    Bosson, Emma (Swedish Nuclear Fuel and Waste Management Co., Stocholm (Sweden)); Sassner, Mona; Sabel, Ulrika; Gustafsson, Lars-Goeran (DHI Sverige AB (Sweden))

    2010-10-15

    Radioactive waste from nuclear power plants in Sweden is managed by the Swedish Nuclear Fuel and Waste Management Co, SKB. SKB has performed site investigations at two different locations in Sweden, referred to as the Forsmark and Laxemar-Simpevarp areas, with the objective of siting a final repository for high-level radioactive waste. In 2009 a decision was made to focus on the Forsmark site. This decision was based on a large amount of empirical evidence suggesting Forsmark to be more suitable for a geological repository /SKB 2010b/. This report presents model results of numerical flow and transport modelling of surface water and near-surface groundwater at the Forsmark site for present and future conditions. Both temperate and periglacial climates have been simulated. Also different locations of the shoreline have been applied to the model, as well as different models of vegetation and Quaternary deposits. The modelling was performed using the modelling tool MIKE SHE and was based on the SDM-Site Forsmark MIKE SHE model (presented by Bosson et al. in SKB report R-08-09). The present work is a part of the biosphere modelling performed for the SR-Site safety assessment. The Forsmark area has a flat, small-scale topography. The study area is almost entirely below 20 m.a.s.l. (metres above sea level). There is a strong correlation between the topography of the ground surface and the ground water level in the Quaternary deposits (QD); thus, the surface water divides and the groundwater divides for the QD can be assumed to coincide. No major water courses flow through the catchment. Small brooks, which often dry out in the summer, connect the different sub-catchments with each other. The main lakes in the area, Lake Bolundsfjaerden, Lake Fiskarfjaerden, Lake Gaellsbotraesket and Lake Eckarfjaerden, all have sizes of less than one km2. The lakes are in general shallow. Approximately 70% of the catchment areas are covered by forest. Agricultural land is only present in

  12. Go-To Telescopes Under Suburban Skies

    CERN Document Server

    Monks, Neale

    2010-01-01

    For the last four centuries stargazers have turned their telescopes to the night skies to look at its wonders, but only in this age of computers has it become possible to let the telescope find for you the object you are looking for! So-called “go-to” telescopes are programmed with the locations of thousands of objects, including dazzling distant Suns, stunning neighboring galaxies, globular and open star clusters, the remnants of past supernovae, and many other breathtaking sights. This book does not tell you how to use your Go-to telescope. Your manual will help you do that. It tells you what to look for in the deep sky and why, and what equipment to best see it with. Organized broadly by what is best for viewing in the northern hemisphere in different seasons, Monks further divides the sights of each season into groupings such as “Showpiece Objects,” “Interesting Deep Sky Objects,” and “Obscure and Challenging Deep Sky Objects.” He also tells what objects are visible even in light-polluted ...

  13. Kinesthetic Astronomy: The Sky Time Lesson.

    Science.gov (United States)

    Morrow, Cherilynn A.

    2000-01-01

    Describes a lesson in which students perform simple body movements in order to gain insight into the relationship between time and the astronomical motions of the earth, and how these motions influence what we see in the sky at various times of the day and year. (WRM)

  14. Sirius brightest diamond in the night sky

    CERN Document Server

    Holberg, Jay B

    2007-01-01

    This book describes why Sirius has been regarded as an important fixture of the night sky since the beginnings of history. It also examines the part that Sirius has played in how we came to achieve our current scientific understanding of stars.

  15. Spectral karyotyping (SKY) in hematological neoplasia

    Science.gov (United States)

    Preiss, Birgitte S.; Pedersen, Rikke K.; Kerndrup, Gitte B.

    2001-07-01

    From November 1, 1997 till November 1, 2000 we have investigated 204 cases of acute myeloid leukemia (AML) (nequals95), acute lymphatic leukemia (ALL) (nequals40), myelodysplastic syndrome (MDS) (nequals11), chronic myeloid leukemia (CML) (nequals9), chronic lymphatic leukemia (CLL) (nequals4) and non-Hodgkin lymphoma (NHL) (nequals45) cytogenetically, using G-band analysis and spectral karyotyping (SKY). By SKY we were able to detect the abnormal clones in all cases but 9. In the G-band preparations these cases showed very few abnormal mitoses. The SKY either extended or confirmed the G-band findings in 94% of those with an abnormal karyotype. Cryptic translocations (translocations not suspected from the G-band karyotype) were found in 71 cases (26 AML, 9 ALL, 5 MDS, 2 CLL and 29 NHL). We find SKY a powerful adjuvant diagnostic tool that does not compromise one of the advantages of karyotyping techniques, the analysis of the entire genome which, in contrast to molecular biological techniques, still leave the possibility to get mroe answers than questions posed.

  16. Observing and drawing the deep sky

    Science.gov (United States)

    Moore, S.

    2004-02-01

    Despite advances in photographic emulsions and the rapid evolution of CCD cameras, drawing is still a valid and enjoyable method of recording the appearance of deep-sky objects. It is cheap, simple and most importantly, you do not have to be a great artist to make a permanent record of what you observe.

  17. Assimilating All-Sky GPM Microwave Imager(GMI) Radiance Data in NASA GEOS-5 System for Global Cloud and Precipitation Analyses

    Science.gov (United States)

    Kim, M. J.; Jin, J.; McCarty, W.; Todling, R.; Holdaway, D. R.; Gelaro, R.

    2014-12-01

    The NASA Global Modeling and Assimilation Office (GMAO) works to maximize the impact of satellite observations in the analysis and prediction of climate and weather through integrated Earth system modeling and data assimilation. To achieve this goal, the GMAO undertakes model and assimilation development, generates products to support NASA instrument teams and the NASA Earth science program. Currently Atmospheric Data Assimilation System (ADAS) in the Goddard Earth Observing System Model, Version 5(GEOS-5) system combines millions of observations and short-term forecasts to determine the best estimate, or analysis, of the instantaneous atmospheric state. However, ADAS has been geared towards utilization of observations in clear sky conditions and the majority of satellite channel data affected by clouds are discarded. Microwave imager data from satellites can be a significant source of information for clouds and precipitation but the data are presently underutilized, as only surface rain rates from the Tropical Rainfall Measurement Mission (TRMM) Microwave Imager (TMI) are assimilated with small weight assigned in the analysis process. As clouds and precipitation often occur in regions with high forecast sensitivity, improvements in the temperature, moisture, wind and cloud analysis of these regions are likely to contribute to significant gains in numerical weather prediction accuracy. This presentation is intended to give an overview of GMAO's recent progress in assimilating the all-sky GPM Microwave Imager (GMI) radiance data in GEOS-5 system. This includes development of various new components to assimilate cloud and precipitation affected data in addition to data in clear sky condition. New observation operators, quality controls, moisture control variables, observation and background error models, and a methodology to incorporate the linearlized moisture physics in the assimilation system are described. In addition preliminary results showing impacts of

  18. Retrieving Clear-Sky Surface Skin Temperature for Numerical Weather Prediction Applications from Geostationary Satellite Data

    Directory of Open Access Journals (Sweden)

    Baojuan Shan

    2013-01-01

    Full Text Available Atmospheric models rely on high-accuracy, high-resolution initial radiometric and surface conditions for better short-term meteorological forecasts, as well as improved evaluation of global climate models. Remote sensing of the Earth’s energy budget, particularly with instruments flown on geostationary satellites, allows for near-real-time evaluation of cloud and surface radiation properties. The persistence and coverage of geostationary remote sensing instruments grant the frequent retrieval of near-instantaneous quasi-global skin temperature. Among other cloud and clear-sky retrieval parameters, NASA Langley provides a non-polar, high-resolution land and ocean skin temperature dataset for atmospheric modelers by applying an inverted correlated k-distribution method to clear-pixel values of top-of-atmosphere infrared temperature. The present paper shows that this method yields clear-sky skin temperature values that are, for the most part, within 2 K of measurements from ground-site instruments, like the Southern Great Plains Atmospheric Radiation Measurement (ARM Infrared Thermometer and the National Climatic Data Center Apogee Precision Infrared Thermocouple Sensor. The level of accuracy relative to the ARM site is comparable to that of the Moderate-resolution Imaging Spectroradiometer (MODIS with the benefit of an increased number of daily measurements without added bias or increased error. Additionally, matched comparisons of the high-resolution skin temperature product with MODIS land surface temperature reveal a level of accuracy well within 1 K for both day and night. This confidence will help in characterizing the diurnal and seasonal biases and root-mean-square differences between the retrievals and modeled values from the NASA Goddard Earth Observing System Version 5 (GEOS-5 in preparation for assimilation of the retrievals into GEOS-5. Modelers should find the immediate availability and broad coverage of these skin temperature

  19. South polar permanent CO2 ice cap presentation in the Global Mars Multiscale Model

    Science.gov (United States)

    Fazel-Rastgar, Farahnaz

    2018-02-01

    The atmospheric influence caused by the Martian permanent south CO2 ice cap is examined to improve the Global Mars Multiscale Model (GM3) to see if it can significantly improve the representation of south polar meteorology. However, the seasonal carbon dioxide ice in the polar regions is presented in the surface ice simulation by the Global Mars Multiscale Model but the model does not produce a permanent south CO2 ice cap, and the physics code must modify to capture the realistic physical such as ice process detail; probably makes a bias in terms of total CO2 ice and meteorological processes in the model aside from ice formation. The permanent south CO2 ice cap in the model can significantly improve the representation of south polar meteorology for example in predicted surface temperatures, surface pressures, horizontal and zonal winds over the south cap and possible initiation of dust storms at south polar region during the southern summer period.

  20. CLIMBER-2: a climate system model of intermediate complexity. Pt. 1. Model description and performance for present climate

    Energy Technology Data Exchange (ETDEWEB)

    Petoukhov, V.; Ganopolski, A.; Brovkin, V.; Claussen, M.; Eliseev, A.; Kubatzki, C.; Rahmstorf, S.

    1998-02-01

    A 2.5-dimensional climate system model of intermediate complexity CLIMBER-2 and its performance for present climate conditions are presented. The model consists of modules describing atmosphere, ocean, sea ice, land surface processes, terrestrial vegetation cover, and global carbon cycle. The modules interact (on-line) through the fluxes of momentum, energy, water and carbon. The model has a coarse spatial resolution, allowing nevertheless to capture the major features of the Earth`s geography. The model describes temporal variability of the system on seasonal and longer time scales. Due to the fact that the model does not employ any type of flux adjustment and has fast turnaround time, it can be used for study of climates significantly different from the present one and allows to perform long-term (multimillennia) simulations. The constraints for coupling the atmosphere and ocean without flux adjustment are discussed. The results of a model validation against present climate data show that the model successfully describes the seasonal variability of a large set of characteristics of the climate system, including radiative balance, temperature, precipitation, ocean circulation and cryosphere. (orig.) 62 refs.

  1. The High Time Resolution Radio Sky

    Science.gov (United States)

    Thornton, D.

    2013-11-01

    each orbit, PSR J1729-2117 which is an unusual isolated recycled pulsar, and PSR J2322-2650 which has a companion of very low mass - just 7 × 10^{-4} {M}_{⊙}, amongst others. I begin this thesis with the study of these pulsars and discuss their histories. In addition, I demonstrate that optical observations of the companions to some of the newly discovered pulsars in the High Time Resolution Universe survey may result in a measurement of their age and that of the pulsar. I have discovered five new extragalactic single radio bursts, confirming them as an astronomical population. These appear to occur frequently, with a rate of 1.0^{+0.6}_{-0.5} × 10^4 sky^{-1} day^{-1}. The sources are likely at cosmological distances - with redshifts between 0.45 and 1.45, making them more than half way to the Big Bang in the most distant case. This implies their luminosities must be enormous, 10^{31} to 10^{33} J emitted in just a few milliseconds. Their source is unknown but I present an analysis of the options. I also perform a population simulation of the bursts which demonstrates how their intrinsic spectrum could be measured, even for unlocalised FRBs: early indications are that the spectral index of FRBs < 0.

  2. Validation of spectral sky radiance derived from all-sky camera images -- a case study

    National Research Council Canada - National Science Library

    Tohsing, K; Schrempf, M; Riechelmann, S; Seckmeyer, G

    2014-01-01

    .... The HSI consists of a commercial compact CCD (charge coupled device) camera equipped with a fish-eye lens and provides hemispherical sky images in three reference bands such as red, green and blue...

  3. To Fly in the Sky.

    Science.gov (United States)

    Brodie, Carolyn S.

    1995-01-01

    Suggests activities for students that focus on airplanes, famous pilots, and travel. Provides a list of suggested titles with the following topics: history of flight and airplanes; airplanes and flying information; paper and model airplanes; Charles Lindbergh; Amelia Earhart; the Wright Brothers; videos; and picture books. (AEF)

  4. Implementing Adaptability in the Standard Reference Model for Intelligent Multimedia Presentation Systems

    NARCIS (Netherlands)

    L. Rutledge (Lloyd); L. Hardman (Lynda); J.R. van Ossenbruggen (Jacco); D.C.A. Bulterman (Dick)

    1998-01-01

    textabstractThis paper discusses the implementation of adaptability in environments that are based on the Standard Reference Model for Intelligent Multimedia Presentation Systems. This adaptability is explored in the context of style sheets, which are represented in such formats as DSSSL. The use of

  5. Mobile Applications in Cell Biology Present New Approaches for Cell Modelling

    Science.gov (United States)

    de Oliveira, Mayara Lustosa; Galembeck, Eduardo

    2016-01-01

    Cell biology apps were surveyed in order to identify whether there are new approaches for modelling cells allowed by the new technologies implemented in tablets and smartphones. A total of 97 apps were identified in 3 stores surveyed (Apple, Google Play and Amazon), they are presented as: education 48.4%, games 26.8% and medicine 15.4%. The apps…

  6. Gamma-sky.net: Portal to the gamma-ray sky

    Science.gov (United States)

    Voruganti, Arjun; Deil, Christoph; Donath, Axel; King, Johannes

    2017-01-01

    http://gamma-sky.net is a novel interactive website designed for exploring the gamma-ray sky. The Map View portion of the site is powered by the Aladin Lite sky atlas, providing a scalable survey image tesselated onto a three-dimensional sphere. The map allows for interactive pan and zoom navigation as well as search queries by sky position or object name. The default image overlay shows the gamma-ray sky observed by the Fermi-LAT gamma-ray space telescope. Other survey images (e.g. Planck microwave images in low/high frequency bands, ROSAT X-ray image) are available for comparison with the gamma-ray data. Sources from major gamma-ray source catalogs of interest (Fermi-LAT 2FHL, 3FGL and a TeV source catalog) are overlaid over the sky map as markers. Clicking on a given source shows basic information in a popup, and detailed pages for every source are available via the Catalog View component of the website, including information such as source classification, spectrum and light-curve plots, and literature references. We intend for gamma-sky.net to be applicable for both professional astronomers as well as the general public. The website started in early June 2016 and is being developed as an open-source, open data project on GitHub (https://github.com/gammapy/gamma-sky). We plan to extend it to display more gamma-ray and multi-wavelength data. Feedback and contributions are very welcome!

  7. Shifting skies: a studio investigation into representations of the sky, atmosphere and weather

    OpenAIRE

    Henriksen, Kari

    2017-01-01

    This project investigates representations of the sky, atmosphere and weather in Western art in order to ascertain the effectiveness of the metaphorical use of atmosphere to convey notions of loss and transience. The exegesis examines the historical representation and meaning of the sky and atmospheric phenomena in Western visual art. This includes a critique of Romanticism and the philosophies of the Sublime. The research explores the conceptual underpinnings of the visual depiction of the...

  8. Accuracy of the hypothetical sky-polarimetric Viking navigation versus sky conditions: revealing solar elevations and cloudinesses favourable for this navigation method.

    Science.gov (United States)

    Száz, Dénes; Farkas, Alexandra; Barta, András; Kretzer, Balázs; Blahó, Miklós; Egri, Ádám; Szabó, Gyula; Horváth, Gábor

    2017-09-01

    According to Thorkild Ramskou's theory proposed in 1967, under overcast and foggy skies, Viking seafarers might have used skylight polarization analysed with special crystals called sunstones to determine the position of the invisible Sun. After finding the occluded Sun with sunstones, its elevation angle had to be measured and its shadow had to be projected onto the horizontal surface of a sun compass. According to Ramskou's theory, these sunstones might have been birefringent calcite or dichroic cordierite or tourmaline crystals working as polarizers. It has frequently been claimed that this method might have been suitable for navigation even in cloudy weather. This hypothesis has been accepted and frequently cited for decades without any experimental support. In this work, we determined the accuracy of this hypothetical sky-polarimetric Viking navigation for 1080 different sky situations characterized by solar elevation θ and cloudiness ρ, the sky polarization patterns of which were measured by full-sky imaging polarimetry. We used the earlier measured uncertainty functions of the navigation steps 1, 2 and 3 for calcite, cordierite and tourmaline sunstone crystals, respectively, and the newly measured uncertainty function of step 4 presented here. As a result, we revealed the meteorological conditions under which Vikings could have used this hypothetical navigation method. We determined the solar elevations at which the navigation uncertainties are minimal at summer solstice and spring equinox for all three sunstone types. On average, calcite sunstone ensures a more accurate sky-polarimetric navigation than tourmaline and cordierite. However, in some special cases (generally at 35° ≤ θ ≤ 40°, 1 okta ≤ ρ ≤ 6 oktas for summer solstice, and at 20° ≤ θ ≤ 25°, 0 okta ≤ ρ ≤ 4 oktas for spring equinox), the use of tourmaline and cordierite results in smaller navigation uncertainties than that of calcite

  9. SkyNet: Modular nuclear reaction network library

    Science.gov (United States)

    Lippuner, Jonas; Roberts, Luke F.

    2017-10-01

    The general-purpose nuclear reaction network SkyNet evolves the abundances of nuclear species under the influence of nuclear reactions. SkyNet can be used to compute the nucleosynthesis evolution in all astrophysical scenarios where nucleosynthesis occurs. Any list of isotopes can be evolved and SkyNet supports various different types of nuclear reactions. SkyNet is modular, permitting new or existing physics, such as nuclear reactions or equations of state, to be easily added or modified.

  10. A simple evaluation of global and diffuse luminous efficacy for all sky conditions in tropical and humid climate

    Energy Technology Data Exchange (ETDEWEB)

    Fakra, A.H.; Boyer, H.; Miranville, F.; Bigot, D. [Building Physics and Systems Laboratory (LPBS), University of La Reunion, 117 rue du general Ailleret, Tampon 97430 (Reunion)

    2011-01-15

    This paper presents initial values of global and diffuse luminous efficacy at Saint-Pierre (Reunion Island). Firstly, data used were measured for a period of 6 months, from February to June 2008. During this period, all defined day-types have been studied (clear, cloudy and intermediate). Generally, the meteorological database of Reunion does not contain information for illuminance values. On the other hand, the local meteorological center has a 60-years-old database for solar irradiance (W/m{sup 2}). So it is important to determine Luminous Efficacy in order to find illuminance from solar irradiance (or luminance from solar radiance). The measured data were analyzed, and empirical constant models were developed and presented in this paper in order to determine luminous efficacy under different sky conditions. A comparison between these empirical constants (models) and existing models has been made. The method used to define sky conditions (overcast, intermediate and clear) and day-types characterization as well as classification will be presented in this work. (author)

  11. Bell violation in the sky

    Energy Technology Data Exchange (ETDEWEB)

    Choudhury, Sayantan [Tata Institute of Fundamental Research, Department of Theoretical Physics, Mumbai (India); TIFR, DTP, Mumbai (India); Panda, Sudhakar [Institute of Physics, Bhubaneswar, Odisha (India); Homi Bhabha National Institute, Mumbai (India); Singh, Rajeev [Savitribai Phule Pune University, Department of Physics, Pune (India)

    2017-02-15

    In this work, we have studied the possibility of setting up Bell's inequality violating experiment in the context of cosmology, based on the basic principles of quantum mechanics. First we start with the physical motivation of implementing the Bell inequality violation in the context of cosmology. Then to set up the cosmological Bell violating test experiment we introduce a model independent theoretical framework using which we have studied the creation of new massive particles by implementing the WKB approximation method for the scalar fluctuations in the presence of additional time-dependent mass contribution in the cosmological perturbation theory. Here for completeness we compute the total number density and the energy density of the newly created particles in terms of the Bogoliubov coefficients using the WKB approximation method. Next using the background scalar fluctuation in the presence of a new time-dependent mass contribution, we explicitly compute the expression for the one point and two point correlation functions. Furthermore, using the results for a one point function we introduce a new theoretical cosmological parameter which can be expressed in terms of the other known inflationary observables and can also be treated as a future theoretical probe to break the degeneracy amongst various models of inflation. Additionally, we also fix the scale of inflation in a model-independent way without any prior knowledge of primordial gravitational waves. Also using the input from a newly introduced cosmological parameter, we finally give a theoretical estimate for the tensor-to-scalar ratio in a model-independent way. Next, we also comment on the technicalities of measurements from isospin breaking interactions and the future prospects of newly introduced massive particles in a cosmological Bell violating test experiment. Further, we cite a precise example of this setup applicable in the context of string theory motivated axion monodromy model. Then we

  12. Presenting 3-D models of geological materials on the World Wide Web

    Science.gov (United States)

    Marschallinger, R.; Johnson, S. E.

    2001-05-01

    In this article, we show how current World Wide Web technology can be used to present computerized 3-D models of geological materials. Unlike traditional, paper-based publishing, World Wide Web documents can incorporate several visualization techniques, some of which allow interactive user control. The concepts behind still images, animations, video sequences, object movies and virtual reality models are introduced. The advantages and pitfalls of the different visualization techniques are described, and their potential for the communication of 3-D models of geological materials is discussed. Web-resources providing the necessary browsing, playback and interaction software as well as specific authoring tools are referenced. In the HTML version of this article, which can be found on the accompanying CD-ROM, examples of 3-D macro- and microstructure reconstructions of geological materials are included as color images, animated sequences and interactive 3-D models.

  13. Modeling δ18O in tropical precipitation and the surface ocean for present-day climate

    Science.gov (United States)

    Brown, J.; Simmonds, I.; Noone, D.

    2006-03-01

    The Melbourne University atmospheric general circulation model with stable water isotope tracers is used to examine the variability of isotopic ratios of precipitation and the surface ocean in the tropics for present-day (1950-1999) climate. Surface ocean isotopic ratios are simulated interactively using a one-dimensional scheme that reproduces key features of the observed tropical isotopic spatial distribution and seasonal and interannual variability. The seasonal and interannual variability of modeled isotopic ratios of tropical precipitation is strongly associated with changes in precipitation amount, in agreement with previous isotopic modeling studies. Modeled isotopic ratios of both precipitation and surface ocean water respond to El Niño-Southern Oscillation (ENSO), although the spatial patterns of ENSO and monsoon isotopic responses differ from observations because of biases in the simulated tropical climate. The model captures the dependence of the interannual variability of precipitation isotopic ratios over the tropical Andes on local temperature and precipitation variability and moisture balance over the Amazon basin but fails to reproduce a significant ENSO precipitation or isotope signal over this region. Modeled precipitation isotopic ratios are significantly correlated with local precipitation amount but not with local or regional temperature at Tibetan Plateau ice core sites on interannual timescales, in disagreement with the interpretation of these ice core records as temperature proxies. Surface ocean isotopic ratios are used to calculate modeled "coral," isotopic ratios which are compared with modern coral records, reproducing observed interannual variability where precipitation is well simulated.

  14. Google Sky as an Interactive Content Delivery System

    Science.gov (United States)

    Parrish, Michael

    2009-05-01

    In support of the International Year of Astronomy New Media Task Group's mission to create online astronomy content, several existing technologies are being leveraged. With this undertaking in mind, Google Sky provides an immersive contextual environment for both exploration and content presentation. As such, it affords opportunities for new methods of interactive media delivery. Traditional astronomy news sources and blogs are able to literally set a story at the location of their topic. Furthermore, audio based material can be complimented by a series of locations in the form of a guided tour. In order to provide automated generation and management of this content, an open source software suite has been developed.

  15. SCExAO: First Results and On-Sky Performance

    Science.gov (United States)

    Currie, Thayne; Guyon, Olivier; Martinache, Frantz; Clergeon, Christophe; McElwain, Michael; Thalmann, Christian; Jovanovic, Nemanja; Singh, Garima; Kudo, Tomoyuki

    2013-01-01

    We present new on-sky results for the Subaru Coronagraphic Extreme Adaptive Optics imager (SCExAO) verifying and quantifying the contrast gain enabled by key components: the closed-loop coronagraphic low-order wavefront sensor (CLOWFS) and focal plane wavefront control ("speckle nulling"). SCExAO will soon be coupled with a high-order, Pyramid wavefront sensor which will yield greater than 90% Strehl ratio and enable 10(exp 6) -10(exp 7) contrast at small angular separations allowing us to image gas giant planets at solar system scales. Upcoming instruments like VAMPIRES, FIRST, and CHARIS will expand SCExAO's science capabilities.

  16. The albedo of snow for partially cloudy skies

    Science.gov (United States)

    Choudhury, B. J.; Chang, A. T. C.

    1980-01-01

    The input parameters of the model are atmospheric precipitable water, ozone content, turbidity, cloud optical thickness, size and shape of ice crystal of snow and surface pressure. The model outputs spectral and integrated solar flux snow reflectance as a function of solar elevation and fractional cloudcover. The model is illustrated using representative parameters for the Antarctic coastal regions. The albedo for a clear sky depends inversely on the solar elevation. At high elevation the albedo depends primarily upon the grain size; at low elevation this dependence is on grain size and shape. The gradient of the albedo-elevation curve increases as the grains get larger and faceted. The albedo for a dense overcast is a few percent higher than the clear sky albedo at high elevations. A simple relation between the grain size and the overcast albedo is obtained. For a set of grain size and shape, the albedo matrices (the albedo as a function of solar elevation and fractional cloudcover) are tabulated.

  17. Sky Dancer: a chaotic system

    Science.gov (United States)

    Cros, Anne; Castillo Flores, Fernando; Le Gal, Patrice

    2008-11-01

    We present the experimental study of a collapsible tube conveying an ascending air flow. An extreme of the membrane tube is mounted on the air blower exit, while the other extreme is free. The flow velocity can be varied. For low speeds -- and tubes short enough -- the cylinder stands up (stable state). As the velocity is increased, the system presents sporadic turbulent fluctuations, when the tube bends and rises again. As the air speed is increased again, the intermittent events become more and more frequent. Films realized in front of the system permit to observe waves that propagate in the tube. We measure that these waves have a sonic speed, confirming previous results. Moreover, films taken from the top of the system allow a quantitative characterization of the transition to chaos. By processing the images, we can reduce the evolution of the system to two states: stable (when it is raised) and chaotic (when the tube fluctuates). The histograms of unstable / stable states are coherent with an intermittent transition in the theory of chaos.

  18. KioskAR: An Augmented Reality Game as a New Business Model to Present Artworks

    Directory of Open Access Journals (Sweden)

    Yoones A. Sekhavat

    2016-01-01

    Full Text Available This paper presents the architecture of KioskAR, which is a pervasive game implemented using augmented reality (AR. This game introduces a new business model that makes it possible for players to present their artworks in virtual kiosks using augmented reality, while they are having fun playing the game. In addition to competition between the players in the game, this game requires social interaction between players to earn more points. A user study is conducted to evaluate the sense of presence and the usability of the application. The results of experiments show that KioskAR can achieve a high level of usability as well as sense of presence.

  19. 3D instantaneous dynamics modeling of present-day Aegean subduction

    Science.gov (United States)

    Glerum, Anne; Spakman, Wim; van Hinsbergen, Douwe; Pranger, Casper

    2017-04-01

    To study the sensitivity of surface observables to subduction and mantle flow, i.e. the coupling of crustal tectonics and the underlying mantle dynamics, we have developed 3D numerical models of the instantaneous crust-mantle dynamics of the eastern Mediterranean. These models comprise both a realistic crust-lithosphere system and the underlying mantle. The focus for this presentation lies on the regional crustal flow response to the present-day Aegean subduction system. Our curved model domain measures 40°x40°x2900km with the Aegean subduction system taken as the geographic center. Model set-ups are based on geological and geophysical data of the eastern Mediterranean. We first create a 3D synthetic geometry of the crust-lithosphere system in a stand-alone program, including the present-day configuration of the plates in the region and crust and lithosphere thickness variations abstracted from Moho and LAB maps (Faccenna et al., 2014, Carafa et al., 2015). In addition we construct the geometry of the Aegean slab from a seismic tomography model (UU-P07; Amaru, 2007) and earthquake hypocenters (NCEDC, 2014). Geometries are then imported into the finite element code ASPECT (Kronbichler et al., 2012) using specially designed plugins. The mantle initial temperature conditions can include deviations from an adiabatic profile obtained from conversion of the UU-P07 seismic velocity anomalies to temperature anomalies using a depth-dependent scaling (Karato, 2008). We model compressible mantle flow for which material properties are obtained from thermodynamics P-T lookup-tables (Perple_X, Connolly, 2009) in combination with nonlinear viscoplastic rheology laws. Sublithospheric flow through the lateral model boundaries is left free via open boundary conditions (Chertova et al., 2012), while plate motion is prescribed at the model sides in terms of relative as well as absolute plate motion velocities (e.g. Doubrovine et al., 2012). So far, we used a free-slip surface, but

  20. Temperature trends during the Present and Last Interglacial periods - a multi-model-data comparison

    Science.gov (United States)

    Bakker, P.; Masson-Delmotte, V.; Martrat, B.; Charbit, S.; Renssen, H.; Gröger, M.; Krebs-Kanzow, U.; Lohmann, G.; Lunt, D. J.; Pfeiffer, M.; Phipps, S. J.; Prange, M.; Ritz, S. P.; Schulz, M.; Stenni, B.; Stone, E. J.; Varma, V.

    2014-09-01

    Though primarily driven by insolation changes associated with well-known variations in Earth's astronomical parameters, the response of the climate system during interglacials includes a diversity of feedbacks involving the atmosphere, ocean, sea ice, vegetation and land ice. A thorough multi-model-data comparison is essential to assess the ability of climate models to resolve interglacial temperature trends and to help in understanding the recorded climatic signal and the underlying climate dynamics. We present the first multi-model-data comparison of transient millennial-scale temperature changes through two intervals of the Present Interglacial (PIG; 8-1.2 ka) and the Last Interglacial (LIG; 123-116.2 ka) periods. We include temperature trends simulated by 9 different climate models, alkenone-based temperature reconstructions from 117 globally distributed locations (about 45% of them within the LIG) and 12 ice-core-based temperature trends from Greenland and Antarctica (50% of them within the LIG). The definitions of these specific interglacial intervals enable a consistent inter-comparison of the two intervals because both are characterised by minor changes in atmospheric greenhouse gas concentrations and more importantly by insolation trends that show clear similarities. Our analysis shows that in general the reconstructed PIG and LIG Northern Hemisphere mid-to-high latitude cooling compares well with multi-model, mean-temperature trends for the warmest months and that these cooling trends reflect a linear response to the warmest-month insolation decrease over the interglacial intervals. The most notable exception is the strong LIG cooling trend reconstructed from Greenland ice cores that is not simulated by any of the models. A striking model-data mismatch is found for both the PIG and the LIG over large parts of the mid-to-high latitudes of the Southern Hemisphere where the data depicts negative temperature trends that are not in agreement with near zero

  1. Modeling nonstationary extreme wave heights in present and future climates of Greek Seas

    Directory of Open Access Journals (Sweden)

    Panagiota Galiatsatou

    2016-01-01

    Full Text Available In this study the generalized extreme value (GEV distribution function was used to assess nonstationarity in annual maximum wave heights for selected locations in the Greek Seas, both in the present and future climates. The available significant wave height data were divided into groups corresponding to the present period (1951–2000, a first future period (2001–2050, and a second future period (2051–2100. For each time period, the parameters of the GEV distribution were specified as functions of time-varying covariates and estimated using the conditional density network (CDN. For each location and selected time period, a total number of 29 linear and nonlinear models were fitted to the wave data, for a given combination of covariates. The covariates used in the GEV-CDN models consisted of wind fields resulting from the Regional Climate Model version 3 (RegCM3 developed by the International Center for Theoretical Physics (ICTP with a spatial resolution of 10 km × 10 km, after being processed using principal component analysis (PCA. The results obtained from the best fitted models in the present and future periods for each location were compared, revealing different patterns of relationships between wind components and extreme wave height quantiles in different parts of the Greek Seas and different periods. The analysis demonstrates an increase of extreme wave heights in the first future period as compared with the present period, causing a significant threat to Greek coastal areas in the North Aegean Sea and the Ionian Sea.

  2. Exploring the Night Sky with Binoculars

    Science.gov (United States)

    Moore, Patrick

    On a clear, starry night, the jewelled beauty and unimaginable immensity of our Universe is awe-inspiring. Star-gazing with binoculars is rewarding and may begin a lifelong hobby! Patrick Moore has painstakingly researched Exploring the Night Sky with Binoculars to describe how to use binoculars for astronomical observation. He explains basic astronomy and the selection of binoculars, then discusses the stars, clusters, nebulae and galaxies that await the observer. The sky seen from northern and southern hemispheres is charted season by season, with detailed maps of all the constellations. The reader can also observe the Sun, Moon, planets, comets and meteors. With many beautiful illustrations, this handbook will be helpful and encouraging to casual observers and those cultivating a more serious interest. The enjoyment of amateur astronomy is now available to everybody.

  3. Simulation of the present-day climate with the climate model INMCM5

    Science.gov (United States)

    Volodin, E. M.; Mortikov, E. V.; Kostrykin, S. V.; Galin, V. Ya.; Lykossov, V. N.; Gritsun, A. S.; Diansky, N. A.; Gusev, A. V.; Iakovlev, N. G.

    2017-12-01

    In this paper we present the fifth generation of the INMCM climate model that is being developed at the Institute of Numerical Mathematics of the Russian Academy of Sciences (INMCM5). The most important changes with respect to the previous version (INMCM4) were made in the atmospheric component of the model. Its vertical resolution was increased to resolve the upper stratosphere and the lower mesosphere. A more sophisticated parameterization of condensation and cloudiness formation was introduced as well. An aerosol module was incorporated into the model. The upgraded oceanic component has a modified dynamical core optimized for better implementation on parallel computers and has two times higher resolution in both horizontal directions. Analysis of the present-day climatology of the INMCM5 (based on the data of historical run for 1979-2005) shows moderate improvements in reproduction of basic circulation characteristics with respect to the previous version. Biases in the near-surface temperature and precipitation are slightly reduced compared with INMCM4 as well as biases in oceanic temperature, salinity and sea surface height. The most notable improvement over INMCM4 is the capability of the new model to reproduce the equatorial stratospheric quasi-biannual oscillation and statistics of sudden stratospheric warmings.

  4. Simulation of the present-day climate with the climate model INMCM5

    Science.gov (United States)

    Volodin, E. M.; Mortikov, E. V.; Kostrykin, S. V.; Galin, V. Ya.; Lykossov, V. N.; Gritsun, A. S.; Diansky, N. A.; Gusev, A. V.; Iakovlev, N. G.

    2017-02-01

    In this paper we present the fifth generation of the INMCM climate model that is being developed at the Institute of Numerical Mathematics of the Russian Academy of Sciences (INMCM5). The most important changes with respect to the previous version (INMCM4) were made in the atmospheric component of the model. Its vertical resolution was increased to resolve the upper stratosphere and the lower mesosphere. A more sophisticated parameterization of condensation and cloudiness formation was introduced as well. An aerosol module was incorporated into the model. The upgraded oceanic component has a modified dynamical core optimized for better implementation on parallel computers and has two times higher resolution in both horizontal directions. Analysis of the present-day climatology of the INMCM5 (based on the data of historical run for 1979-2005) shows moderate improvements in reproduction of basic circulation characteristics with respect to the previous version. Biases in the near-surface temperature and precipitation are slightly reduced compared with INMCM4 as well as biases in oceanic temperature, salinity and sea surface height. The most notable improvement over INMCM4 is the capability of the new model to reproduce the equatorial stratospheric quasi-biannual oscillation and statistics of sudden stratospheric warmings.

  5. A review of the evidence linking adult attachment theory and chronic pain: presenting a conceptual model.

    Science.gov (United States)

    Meredith, Pamela; Ownsworth, Tamara; Strong, Jenny

    2008-03-01

    It is now well established that pain is a multidimensional phenomenon, affected by a gamut of psychosocial and biological variables. According to diathesis-stress models of chronic pain, some individuals are more vulnerable to developing disability following acute pain because they possess particular psychosocial vulnerabilities which interact with physical pathology to impact negatively upon outcome. Attachment theory, a theory of social and personality development, has been proposed as a comprehensive developmental model of pain, implicating individual adult attachment pattern in the ontogenesis and maintenance of chronic pain. The present paper reviews and critically appraises studies which link adult attachment theory with chronic pain. Together, these papers offer support for the role of insecure attachment as a diathesis (or vulnerability) for problematic adjustment to pain. The Attachment-Diathesis Model of Chronic Pain developed from this body of literature, combines adult attachment theory with the diathesis-stress approach to chronic pain. The evidence presented in this review, and the associated model, advances our understanding of the developmental origins of chronic pain conditions, with potential application in guiding early pain intervention and prevention efforts, as well as tailoring interventions to suit specific patient needs.

  6. Aquarius L-Band Radiometers Calibration Using Cold Sky Observations

    Science.gov (United States)

    Dinnat, Emmanuel P.; Le Vine, David M.; Piepmeier, Jeffrey R.; Brown, Shannon T.; Hong, Liang

    2015-01-01

    An important element in the calibration plan for the Aquarius radiometers is to look at the cold sky. This involves rotating the satellite 180 degrees from its nominal Earth viewing configuration to point the main beams at the celestial sky. At L-band, the cold sky provides a stable, well-characterized scene to be used as a calibration reference. This paper describes the cold sky calibration for Aquarius and how it is used as part of the absolute calibration. Cold sky observations helped establish the radiometer bias, by correcting for an error in the spillover lobe of the antenna pattern, and monitor the long-term radiometer drift.

  7. All-sky radiance simulation of Megha-Tropiques SAPHIR microwave ...

    Indian Academy of Sciences (India)

    Incorporation of cloud- and precipitation-affected radiances from microwave satellite sensors in data assimilation system has a great potential in improving the accuracy of numerical model forecasts over the regions of high impact weather. By employing the multiple scattering radiative transfer model RTTOVSCATT,all-sky ...

  8. Stellar mass of elliptical galaxies in the Sloan Digital Sky Survey

    Science.gov (United States)

    Chen, Chen-Hung; Ko, Chung-Ming

    2015-08-01

    Stellar mass is an important ingredient in the study of the evolution of galaxies. As an alternative to the dark matter paradigm, MOdified Newtonian Dynamics (MOND) provides us a tool to estimate more directly the baryonic mass of a galaxy via its dynamical mass. As most baryons are resided in stars in an elliptical galaxy, we estimate its stellar mass by calculating its dynamical mass in the framework of MOND. Hernquist model is adopted for the mass distribution. We select elliptical galaxies with measured velocity dispersion and effective radius between redshift 0.05 and 0.5 from the main galaxy sample and the luminous red galaxy sample in the Sloan Digital Sky Survey. In this contribution we present the evolution of the stellar mass of elliptical galaxies with redshift.

  9. Alligator Rivers Analogue project. Geochemical modelling of present-day groundwaters. Final Report - Volume 12

    Energy Technology Data Exchange (ETDEWEB)

    Sverjensky, D. A. [The John Hopkins Univ, Dept of Earth and Planetary Sciences, Baltimore (United States)

    1992-12-31

    The main purpose of this report is to summarize geochemical modeling studies of the present-day Koongarra groundwaters. Information on the present-day geochemistry and geochemical processes at Koongarra forms a basis for a present-day analogue for nuclear waste migration. The present-day analogue is built on studies of the mineralogy and petrology of the Koongarra deposit, and chemical analyses of present-day groundwaters from the deposit. The overall approach taken in the present study has been to carry out a series of aqueous speciation and state of saturation calculations, including chemical mass transfer calculations, to address the possible control over the chemistry of the present-day for the groundwaters at Koongarra. The most important implication of the present study for the migration of radionuclides is the strong role played by the water-rock interactions, both above and below the water table, influencing the overall chemical evolution of the groundwaters. Thus, the results show that the chemical evolution of waters is strongly controlled by the initial availability of CO{sub 2} and the mineral assemblage encountered, which together determine the major element evolution of the waters by controlling the pH. The relative rates of evolution of the pH and the oxidation state of the groundwaters are also critical to the mobility of uranium. The shallow Koongarra waters are sufficiently oxidising that they can dissolve and transport uranium even under acidic conditions. Under the more reducing condition of the deep groundwaters, is the pH level that permits uranium transport as carbonate complexes. However, if the oxidation state decreases to much lower levels, it would be expected that uranium become immobile. All the speciation and state of saturation calculations carried out in the present study are available from the author, on request 22 refs., 7 tabs., 18 figs.

  10. Presenting the Students' Academic Achievement Causal Model based on Goal Orientation.

    Science.gov (United States)

    Nasiri, Ebrahim; Pour-Safar, Ali; Taheri, Mahdokht; Sedighi Pashaky, Abdullah; Asadi Louyeh, Ataollah

    2017-10-01

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

  11. Chemistry-climate model SOCOL: a validation of the present-day climatology

    Directory of Open Access Journals (Sweden)

    T. Egorova

    2005-01-01

    Full Text Available In this paper we document 'SOCOL', a new chemistry-climate model, which has been ported for regular PCs and shows good wall-clock performance. An extensive validation of the model results against present-day climate data obtained from observations and assimilation data sets shows that the model describes the climatological state of the atmosphere for the late 1990s with reasonable accuracy. The model has a significant temperature bias only in the upper stratosphere and near the tropopause at high latitudes. The latter is the result of the rather low vertical resolution of the model near the tropopause. The former can be attributed to a crude representation of radiation heating in the middle atmosphere. A comparison of the simulated and observed link between the tropical stratospheric structure and the strength of the polar vortex shows that in general, both observations and simulations reveal a higher temperature and ozone mixing ratio in the lower tropical stratosphere for the case with stronger Polar night jet (PNJ and slower Brewer-Dobson circulation as predicted by theoretical studies.

  12. The cosmological principle is not in the sky

    Science.gov (United States)

    Park, Chan-Gyung; Hyun, Hwasu; Noh, Hyerim; Hwang, Jai-chan

    2017-08-01

    The homogeneity of matter distribution at large scales, known as the cosmological principle, is a central assumption in the standard cosmological model. The case is testable though, thus no longer needs to be a principle. Here we perform a test for spatial homogeneity using the Sloan Digital Sky Survey Luminous Red Galaxies (LRG) sample by counting galaxies within a specified volume with the radius scale varying up to 300 h-1 Mpc. We directly confront the large-scale structure data with the definition of spatial homogeneity by comparing the averages and dispersions of galaxy number counts with allowed ranges of the random distribution with homogeneity. The LRG sample shows significantly larger dispersions of number counts than the random catalogues up to 300 h-1 Mpc scale, and even the average is located far outside the range allowed in the random distribution; the deviations are statistically impossible to be realized in the random distribution. This implies that the cosmological principle does not hold even at such large scales. The same analysis of mock galaxies derived from the N-body simulation, however, suggests that the LRG sample is consistent with the current paradigm of cosmology, thus the simulation is also not homogeneous in that scale. We conclude that the cosmological principle is neither in the observed sky nor demanded to be there by the standard cosmological world model. This reveals the nature of the cosmological principle adopted in the modern cosmology paradigm, and opens a new field of research in theoretical cosmology.

  13. The Second Data Release of the Sloan Digital Sky Survey

    CERN Document Server

    Abazajian, Kevork; ̈ueros, Marcel A. Ag; Allam, Sahar S.; Anderson, KurtS. J.; Anderson, Scott F.; Annis, James; Bahcall, Neta A.; Baldry, Ivan K.; StevenBastian; Berlind, Andreas; Bernardi, Mariangela; Blanton, Michael R.; BochanskiJr., John J.; Boroski, William N.; Briggs, John W.; Brinkmann, J.; Brunner, Robert J.; ́ari, Tam ́asBudav; Carey, Larry N.; Carliles, Samuel; Castander, Francisco J.; Connolly, A. J.; Csabai, Istvan; Doi, Mamoru; Dong, Feng; Eisenstein, Daniel J.; Evans, Michael L.; Fan, Xiaohui; Finkbeiner, Douglas P.; Friedman, Scott D.; Frieman, Joshua A.; Fukugita, Masataka; Gal, RoyR.; Gillespie, Bruce; Glazebrook, Karl; Gray, Jim; Grebel, Eva K.; Gunn, James E.; Gurbani, Vijay K.; Hall, Patrick B.; Hamabe, Masaru; Harris, Frederick H.; C.Harris, Hugh; Harvanek, Michael; Heckman, Timothy M.; Hendry, John S.; Hennessy, Gregory S.; Hindsley, Robert B.; Hogan, Craig J.; Hogg, David W.; Holmgren, Donald J.; Ichikawa, Shin-ichi; Ichikawa, Takashi; Ivezic, Zeljko; Jester, Sebastian; Johnston, David E.; Jorgensen, AndersM.; Kent, Stephen M.; Kleinman, S. J.; Knapp, G. R.; Kniazev, Alexei Yu.; Kron, Richard G.; Krzesinski, Jurek; Kunszt, Peter Z.; Kuropatkin, Nickolai; Q.Lamb, Donald; Lampeitl, Hubert; Lee, Brian C.; Leger, R. French; Li, Nolan; Lin, Huan; Loh, Yeong-Shang; Long, Daniel C.; Loveday, Jon; Lupton, Robert H.; Malik, Tanu; BruceMargon; Matsubara, Takahiko; McGehee, Peregrine M.; McKay, Timothy A.; AveryMeiksin; Munn, Jeffrey A.; Nakajima, Reiko; Nash, Thomas; Neilsen, Eric H. Jr.; JoNewberg, Heidi; Newman, Peter R.; Nichol, Robert C.; Nicinski, Tom; Nieto-Santisteban, Maria; Nitta, Atsuko; Okamura, Sadanori; O'Mullane, William; Ostriker, Jeremiah P.; Owen, Russell; Padmanabhan, Nikhil; Peoples, John; Pier, Jeffrey R.; Pope, Adrian C.; Quinn, Thomas R.; Richards, Gordon T.; Richmond, Michael W.; Rix, Hans-Walter; Rockosi, Constance M.; Schlegel, David J.; Schneider, Donald P.; Scranton, Ryan; Sekiguchi, Maki; Seljak, Uros; Sergey, Gary; Sesar, Branimir; Sheldon, Erin; Shimasaku, Kazu; Siegmund, Walter A.; Silvestri, Nicole M.; Smith, J. Allyn; ́c, Vernesa Smolči; Snedden, Stephanie A.; AlbertStebbins; Stoughton, Chris; Strauss, Michael A.; SubbaRao, Mark; Szalay, Alexander S.; Szapudi, Istv ́an; Szkody, Paula; Szokoly, Gyula P.; Tegmark, Max; Teodoro, Luis; Thakar, AniruddhaR.; Tremonti, Christy; Tucker, Douglas L.; Uomoto, Alan; Vanden Berk, Daniel E.; Vandenberg, Jan; Vogeley, Michael S.; Voges, Wolfgang; Vogt, Nicole P.; M.Walkowicz, Lucianne; Wang, Shu-i; Weinberg, David H.; West, Andrew A.; White, Simon D.M.; Wilhite, BrianC.; Xu, Yongzhong; Yanny, Brian; Yasuda, Naoki; Yip, Ching-Wa; Yocum, D. R.; York, Donald G.; Zehavi, Idit; Zibetti, Stefano; Zucker, Daniel B.

    2004-01-01

    The Sloan Digital Sky Survey has validated and made publicly available its Second Data Release. This data release consists of 3324 square degrees of five-band (u g r i z) imaging data with photometry for over 88 million unique objects, 367,360 spectra of galaxies, quasars, stars and calibrating blank sky patches selected over 2627 degrees of this area, and tables of measured parameters from these data. The imaging data reach a depth of r ~ 22.2 (95% completeness limit for point sources) and are photometrically and astrometrically calibrated to 2% rms and 100 milli-arcsec rms per coordinate, respectively. The imaging data have all been processed through a new version of the SDSS imaging pipeline, in which the most important improvement since the last data release is fixing an error in the model fits to each object. The result is that model magnitudes are now a good proxy for point spread function (PSF) magnitudes for point sources, and Petrosian magnitudes for extended sources. The spectroscopy extends from 38...

  14. The Catalina Sky Survey: Status, Discoveries and the Future

    Science.gov (United States)

    Johnson, Jess A.; Christensen, Eric J.; Gibbs, Alex R.; Grauer, Albert D.; Hill, Richard E.; Kowalski, Richard A.; Larson, Steve M.; Shelly, Frank J.

    2014-11-01

    On 1 January 2014, the Catalina Sky Survey kicked off its year with the discovery of 2014 AA, a small Apollo-type NEO that entered the atmosphere over the mid-Atlantic ocean 21 hours after discovery. As of 12 August 2014, the Catalina Sky Survey (CSS) has discovered 5192 Near Earth Objects. Accounting for nearly two thirds of all NEO discoveries since 2005, and over 46% of all known NEOs, CSS has a long history of being an effective dedicated NEO survey, and pending upgrades will allow it to continue its productivity into the foreseeable future.We present an overview of our facilities and equipment, the current status of survey operations, an overview of recent discoveries and discovery statistics, and the status of recent and pending upgrades to our instrumentation and equipment. The 1.0m follow-up telescope on Mt. Lemmon is now operational (MPC code I52) and providing asteroid astrometry. A new camera for the 1.5 m telescope (G96) will increase the field four times to 5 square degrees and may be operational by the end of the year. A similar camera for the Catalina Schmidt telescope (703) will follow with a 19.4 square degree field. These upgrades will substantially increase the NEO discovery rate from CSS. Additionally, software upgrades to accommodate the larger data flow are in process. Finally, we will discuss ways in which our data are being used for other purposes within the astronomical community, including the search for optical transients (Catalina Real-Time Transient Survey), and the public search for NEOs through the Asteroid Zoo program, developed by Planetary Resources, Inc. in collaboration with CSS and Zooniverse, under the auspices of NASA's Asteroid Grand Challenge initiative. The Catalina Sky Survey is funded by NASA’s Near Earth Objects Observation Program.

  15. The GLOBE at Night Campaign: Promoting Dark Skies Awareness Beyond IYA2009

    Science.gov (United States)

    Walker, Constance E.

    2010-01-01

    One of the most productive programs in the IYA2009 Dark Skies Awareness Cornerstone Project has been GLOBE at Night. The GLOBE at Night program has endeavored to promote social awareness of the dark sky by getting the general public to measure light pollution and submit results on-line. During IYA2009 alone, over 15,700 measurements from 70 countries were contributed during the 2-week campaign period. That amount is twice the number of measurements on average from previous years. The GLOBE at Night website explains clearly the simple-to-participate-in 5 step program and offers background information and interactive games on key concepts. The program has been expanded to include trainings of the general public, but especially educators in schools, museums and science centers, in unique ways. Education kits for Dark Skies Awareness have been distributed at these training workshops. The kit includes material for a light shielding demonstration, a digital Sky Quality Meter and Dark Skies Ranger Activities. The activities are on how unshielded light wastes energy, how light pollution affects wildlife and how you can participate in a citizen-science star-hunt like GLOBE at Night. In addition, projects are being developed for what to do with the data once it is taken. There were particularly spirited and creative GLOBE at Night campaigns around the world in 2009. One such "poster child” was carried out by 6500 students in northern Indiana. The students produced 3,391 GLOBE at Night measurements. To visualize the magnitudes of dark sky lost to light pollution, these students removed over 12,000 of the 35,000 stacked LEGO blocks that represented an ideal night sky across the school district. The presentation will provide an update with lessons learned, describe how people can become involved and take a look ahead at the program's sustainability. For further information, visit www.globe.gov/globeatnight.

  16. Dark Skies Ahead? Activities to Raise Awareness during the International Year of Astronomy

    Science.gov (United States)

    Walker, Constance E.; Isbell, D.; Pompea, S.

    2007-12-01

    "Dark Skies as a Universal Resource” is one of 7 themes targeted for the International Year of Astronomy in 2009. The theme's goal is to raise public awareness of the impact of artificial lighting on local environments and the ongoing loss of a dark night sky as a natural resource for much of the world's population. To reach this goal, activities are being developed which highlight dark skies preservation issues 1) through new technology (e.g., programs at planetaria, blogging, podcasting); 2) at events such as star parties and observatory open houses; 3) in arts, entertainment and storytelling (e.g., art competitions, documentaries, lectures, native American traditions); 4) through unaided-eye and digital-meter star count programs involving citizen-scientists; and 5) by relating them to public health, economic issues, ecological consequences, energy conservation, safety and security. A centerpiece of the Dark Skies theme is the unaided-eye and digital-meter versions of the GLOBE at Night program. The unaided-eye version directs citizen-scientists on how to observe and record the brightness of the night sky by matching its appearance toward the constellation of Orion with one of 7 stellar maps of different limiting magnitudes. For the "digital” version, low-cost meters are used by citizen-scientists to measure the integrated sky brightness. Data sets and maps of both versions are supplied on-line for further capstone activities. In the presentation, we will outline the activities being developed as well as plans for funding, implementation, marketing and the connections to the global cornerstone IYA project, "Dark Skies Awareness".

  17. The interactive sky: a browsable allsky image

    Science.gov (United States)

    Tancredi, Gonzalo; Da Rosa, Fernando; Roland, Santiago; Almenares, Luciano; Gomez, Fernando

    2015-08-01

    We are conducting a project to make available panoramas of the night sky of the southern hemisphere, based on a mosaic of hundred of photographs. Each allsky panorama is a giant image composed by hundreds of high-resolution photos taken in the course of one night. The panoramas are accessible with a web-browser and the public is able to zoom on them and to see the sky with better quality than the naked eye. We are preparing 4 sets of panoramas corresponding to the four seasons.The individual images are taken with a 16 Mpixels DLSR camera with a 50 mm lens mounted on a Gigapan EPIC robotic camera mounts. These devices and a autoguiding telescope are mounted in a equatorial telescope mount, which allows us to have exposure of several tens seconds. The images are then processed and stitched to create the gigantic panorama, with typical weight of several GBytes.The limiting magnitude is V~8. The panoramas include more than 50 times more stars those detected with the naked eye.In addition to the allsky panoramas, we embedded higher resolution images of specific regions of interest such as: emission nebulae and dark, open and globular clusters and galaxies; which can be zoomed.The photographs have been acquiring since December 2014 in a dark place with low light pollution in the countryside of Uruguay; which allows us to achieve deep sky objects.These panoramas will be available on a website and can be accessed with any browser.This tool will be available for teaching purposes, astronomy popularization or introductory research. Teacher guides will be developed for educational activities at different educational levels.While there are similar projects like Google Sky, the methodology used to generate the giant panoramas allows a much more realistic view, with a background of continuous sky without sharp edges. Furthermore, while the planetarium software is based on drawings of the stars, our panoramas are based on real images.This is the first project with these

  18. Future Sky Surveys: New Discovery Frontiers

    Science.gov (United States)

    Tyson, J. Anthony; Borne, Kirk D.

    2012-03-01

    Driven by the availability of new instrumentation, there has been an evolution in astronomical science toward comprehensive investigations of new phenomena. Major advances in our understanding of the Universe over the history of astronomy have often arisen from dramatic improvements in our capability to observe the sky to greater depth, in previously unexplored wavebands, with higher precision, or with improved spatial, spectral, or temporal resolution. Substantial progress in the important scientific problems of the next decade (determining the nature of dark energy and dark matter, studying the evolution of galaxies and the structure of our own Milky Way, opening up the time domain to discover faint variable objects, and mapping both the inner and outer Solar System) can be achieved through the application of advanced data mining methods and machine learning algorithms operating on the numerous large astronomical databases that will be generated from a variety of revolutionary future sky surveys. Over the next decade, astronomy will irrevocably enter the era of big surveys and of really big telescopes. New sky surveys (some of which will produce petabyte-scale data collections) will begin their operations, and one or more very large telescopes (ELTs = Extremely Large Telescopes) will enter the construction phase. These programs and facilities will generate a remarkable wealth of data of high complexity, endowed with enormous scientific knowledge discovery potential. New parameter spaces will be opened, in multiple wavelength domains as well as the time domain, across wide areas of the sky, and down to unprecedented faint source flux limits. The synergies of grand facilities, massive data collections, and advanced machine learning algorithms will come together to enable discoveries within most areas of astronomical science, including Solar System, exo-planets, star formation, stellar populations, stellar death, galaxy assembly, galaxy evolution, quasar evolution

  19. Modelling present and future African climate using CMIP5scenarios in HadGEM2-ES

    Science.gov (United States)

    Shimizu, M. H.; Diallo, M.; Dike, V. N.

    2014-12-01

    The present precipitation and temperature patterns and expected future changes (2073-2098) in Africa are investigated using the Hadley Centre Global Environmental Model 2-Earth System (HadGEM2-ES) under the fifth phase of the Coupled Model Intercomparison Project (CMIP5) protocols for historical and future emission scenarios simulations.In a CMIP5 multimodel analysis, the annual cycles of temperature and precipitation simulated by HadGEM2-ES were very close to the multimodel ensemble mean. HadGEM2-ES temperature simulation compares well with the National Center for Atmospheric Research (NCAR) reanalysis over the 1979-2004 periods, except for a summer overestimation in Central Africa, and a winter underestimation in tropical West Africa. The precipitation simulation compared well with the Global Precipitation Climatology Project (GPCP) data from 1979 to 2004 over the entire Africa, except in the Intertropical Convergence Zone (ITCZ), where the model fails to capture adequately the transition phase of the monsoon circulation. The dry regimes over Northern Africa as well as the wetter regime occurring over Central Africa, which is mainly regulated by the ITCZ displacement, and during the austral summer of Southern Africa, are also fairly reproduced by the HadGEM2-ES model. The model projects for the end of the 21st century a rainy South Africa, a change of the flood/drought cycle in the Tropics and a warming over the whole continent, varying from 3 to 7 ∘ C. HadGEM2-ES performance for Nigeria shows good reproduction of precipitation seasonal cycles for some locations, outside the ITCZ. However, the comparison with in situ measurement in Ilorin and Lagos shows the model is not being able to reproduce the precipitation annual cycle. Future projections for Nigeria exhibit warming everywhere and an enhancement of precipitation, especially in the northern part of the country.

  20. Models and (some) Searches for CPT Violation: From Early Universe to the Present Era

    Science.gov (United States)

    Mavromatos, Nick E.

    2017-07-01

    In the talk, I review theoretical models, inspired by quantum gravity, that may violate CPT symmetry. The amount of violation today (which is constrained severely by a plethora of experiments that I will not describe due to lack of space) need not be the same with the one that occurred in the Early Universe,. In certain models, one can obtain a precise temperature dependence of CPT violating effects, which is such that these effects are significant during the radiation era of the Universe, but are damped quickly so that they do not to affect nucleosynthesis and are negligible in the present epoch (that is, beyond experimental detection with the current experimental sensitivity). The CPT Violation (CPTV) in these models may arise from special properties of the background over which the fields of the model are propagating upon and be responsible for the generation of a matter-antimatter asymmetry, where any CP violation effects could only assist in the creation of the asymmetry, the dominant effect being CPTV. However, there are cases, where the CPTV arises as a consequence of an ill-defined CPT operator due to decoherence as a result of quantum gravity environmental degrees of freedom, inaccessible to a low-energy observer. I also discuss briefly the current-era phenomenology of some of the above models; in particular, for the ones involving decoherence-induced CPT violation, I argue that entangled states of neutral mesons (Kaons or B-systems) can provide smoking-gun sensitive tests or even falsify some of these models. If CPT is ill-defined one may also encounter violations of the spin-statistics theorem, with possible consequences for the Pauli Exclusion Principle.

  1. International spring school observing the X-and gamma-ray sky

    Energy Technology Data Exchange (ETDEWEB)

    Paul, J.; Longair, M.; Von Ballmoos, P.; Daigne, F.; Baring, M.; Gudel, M.; King, A.; Dotani, T.; Arnaud, M.; Gudel, M.; Malzac, J.; Servillat, M.; Soldi, S.; Corbel, S.; Beckmann, V.; Rodriguez, J.; Erlund, M.; Bodaghee, A.; Graham, J.; Ruiz, A.; Corbel, S.; Fabian, A.; Tagger, M.; Grenier, I.; Bernard, R.; Jackson, N.; Eckart, A.; Grenier, I.; Belloni, T.; Stella, L.; Vink, J.; KnodLseder, J.; Hermsen, W.; Ferrando, Ph.; Ibragimov, A

    2006-07-01

    This school, dedicated to young researchers, will clarify our present knowledge of the X-ray sky and give the opportunity to learn about the observatories and tools which are available. The contributions have been organized into 3 issues: -) fundamental physics, -) X-ray and Gamma-ray instruments and analysis techniques, and -) astrophysical objects. This document gathers only the slides of the presentations.

  2. Developing an efficient modelling and data presentation strategy for ATDEM system comparison and survey design

    Science.gov (United States)

    Combrinck, Magdel

    2015-10-01

    Forward modelling of airborne time-domain electromagnetic (ATDEM) responses is frequently used to compare systems and design surveys for optimum detection of expected mineral exploration targets. It is a challenging exercise to display and analyse the forward modelled responses due to the large amount of data generated for three dimensional models as well as the system dependent nature of the data. I propose simplifying the display of ATDEM responses through using the dimensionless quantity of signal-to-noise ratios (signal:noise) instead of respective system units. I also introduce the concept of a three-dimensional signal:noise nomo-volume as an efficient tool to visually present and analyse large amounts of data. The signal:noise nomo-volume is a logical extension of the two-dimensional conductance nomogram. It contains the signal:noise values of all system time channels and components for various target depths and conductances integrated into a single interactive three-dimensional image. Responses are calculated over a complete survey grid and therefore include effects of system and target geometries. The user can interactively select signal:noise cut-off values on the nomo-volume and is able to perform visual comparisons between various system and target responses. The process is easy to apply and geophysicists with access to forward modelling airborne electromagnetic (AEM) and three-dimensional imaging software already possess the tools required to produce and analyse signal:noise nomo-volumes.

  3. The Relationship between Spiritual Health and other Dimensions of Health: Presentation of a Model

    Directory of Open Access Journals (Sweden)

    Akram Heidari

    2016-06-01

    Full Text Available Attitudes to humankind will have different effects on health service delivery. Health might used to be intended to provide physical health in the past; today, however, many researchers and clinicians consider the concept health to be beyond physical health. In support of this claim, it is enough to indicate that the bio-psycho-social model has for years been held by scientific communities to be a fully admitted model. However, the missing ring in this model, as suggested by many, is the spiritual health. In recent years, the relationship between spirituality and clinical interventions with a comprehensive focus on health has been under increasing scrutiny. Although different models have been presented for investigation of the relationship between spiritual health and other dimensions, the fundamental challenge in this regard is the actual place of spiritual health compared with other dimensions. In this article, attempts are made to address the position and weight of spiritual health from the Islam’s point of view.

  4. Evolution of the Model of the Clinical Practice of Emergency Medicine: 1979 to Present.

    Science.gov (United States)

    Counselman, Francis L; Beeson, Michael S; Marco, Catherine A; Adsit, Susan K; Harvey, Anne L; Keehbauch, Julia N

    2017-02-01

    The Model of the Clinical Practice of Emergency Medicine (the EM Model) is a three-dimensional representation of the clinical practice of emergency medicine. It is a product of successful collaboration involving the American Board of Emergency Medicine (ABEM), the American College of Emergency Physicians (ACEP), the Society for Academic Emergency Medicine (SAEM), the Emergency Medicine Residents' Association (EMRA), the Council of Emergency Medicine Residency Directors (CORD), the Residency Review Committee for Emergency Medicine (RRC-EM), and the American Academy of Emergency Medicine (AAEM). In 2017, the most recent update and revision of the EM Model will be published. This document will represent the culmination of nearly 40 years of evolution, from a simple listing of presenting patient complaints, clinical symptoms, and disease states into a three-dimensional representation of the clinical practice of emergency medicine. These dimensions include conditions and components, physician tasks, and patient acuity. In addition, over the years, two other documents have been developed, the Knowledge, Skills, and Abilities (KSAs) and the Emergency Medicine Milestones. Both serve as related and complementary educational and assessment tools. This article will review the development of the EM Model from its inception in 1979 to today. © 2016 by the Society for Academic Emergency Medicine.

  5. Estimation of clear sky hourly global solar radiation in Iraq

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jumaily, Kais J.; Al-Zuhairi, Munya F.; Mahdi, Zahraa S. [Department of Atmospheric Sciences, College of Science, Al-Mustansiriyah University, Baghdad (Iraq)

    2012-07-01

    The availability of hourly solar radiation data is very important for applications utilizing solar energy and for climate and environmental aspects. The aim of this work is to use a simple model for estimating hourly global solar radiation under clear sky condition in Iraq. Calculations were compared with measurements obtained from local station in Baghdad city and from Meteosat satellite data for different locations in Iraq. The statistical test methods of the mean bias error (MBE), root mean square error (RMSE) and t-test were used to evaluate the performance of the model. Results indicated that a fairly good agreement exists between calculated and measured values for all locations in Iraq. Since the model is independent of any meteorological variable, it would be of a practical use for rural areas where no meteorological data are available.

  6. Analysis of Ozone in Cloudy Versus Clear Sky Conditions

    Science.gov (United States)

    Strode, Sarah; Douglass, Anne; Ziemke, Jerald

    2016-01-01

    Convection impacts ozone concentrations by transporting ozone vertically and by lofting ozone precursors from the surface, while the clouds and lighting associated with convection affect ozone chemistry. Observations of the above-cloud ozone column (Ziemke et al., 2009) derived from the OMI instrument show geographic variability, and comparison of the above-cloud ozone with all-sky tropospheric ozone columns from OMI indicates important regional differences. We use two global models of atmospheric chemistry, the GMI chemical transport model (CTM) and the GEOS-5 chemistry climate model, to diagnose the contributions of transport and chemistry to observed differences in ozone between areas with and without deep convection, as well as differences in clean versus polluted convective regions. We also investigate how the above-cloud tropospheric ozone from OMI can provide constraints on the relationship between ozone and convection in a free-running climate simulation as well as a CTM.

  7. The Sondrestrom Research Facility All-sky Imagers

    Science.gov (United States)

    Kendall, E. A.; Grill, M.; Gudmundsson, E.; Stromme, A.

    2010-12-01

    The Sondrestrom Upper Atmospheric Research Facility is located near Kangerlussuaq, Greenland, just north of the Arctic Circle and 100 km inland from the west coast of Greenland. The facility is operated by SRI International in Menlo Park, California, under the auspices of the U.S. National Science Foundation. Operating in Greenland since 1983, the Sondrestrom facility is host to more than 20 instruments, the majority of which provide unique and complementary information about the arctic upper atmosphere. Together these instruments advance our knowledge of upper atmospheric physics and determine how the tenuous neutral gas interacts with the charged space plasma environment. The suite of instrumentation supports many disciplines of research - from plate tectonics to auroral physics and space weather. The Sondrestrom facility has recently acquired two new all-sky imagers. In this paper, we present images from both new imagers, placing them in context with other instruments at the site and detailing to the community how to gain access to this new data set. The first new camera replaces the intensified auroral system which has been on site for nearly three decades. This new all-sky imager (ASI), designed and assembled by Keo Scientific Ltd., employs a medium format 180° fisheye lens coupled to a set of five 3-inch narrowband interference filters. The current filter suite allows operation at the following wavelengths: 750 nm, 557.7 nm, 777.4 nm, 630.0 nm, and 732/3 nm. Monochromatic images from the ASI are acquired at a specific filter and integration time as determined by a unique configuration file. Integrations as short as 0.5 sec can be commanded for exceptionally bright features. Preview images are posted to the internet in near real-time, with final images posted weeks later. While images are continuously collected in a "patrol mode," users can request special collection sequences for targeted experiments. The second new imager installed at the Sondrestrom

  8. The VLA Sky Survey (VLASS): Overview and First Results

    Science.gov (United States)

    Myers, Steven T.; VLASS Survey Team, Survey Science Group (SSG)

    2018-01-01

    The VLA Sky Survey (VLASS) is a 5520 hour spectropolarimetric synoptic survey covering the 33885 square degrees of the sky above Declination -40 degrees from 2-4 GHz at 2.5" angular resolution using the upgraded Karl G. Jansky Very Large Array (VLA). Over the survey duration of 7 years, each area of the sky will be covered in 3 epochs spaced 32 months apart, to a projected depth of 0.12mJy/beam rms noise per epoch and 0.07mJy/beam for 3 epochs combined. The VLASS employs on-the-fly mosaicking (OTFM) to rapidly scan the sky with a net speed of approximately 20 sq. degrees per hour. The high-level science goals for the survey include the identification and precise location of radio transients, the measurement of magnetic fields in our galaxy and beyond, and the study of radio emission from galaxies and active galactic nuclei throughout the Universe. The ability of the VLASS to see through dust allows us to unveil phenomena such as hidden cosmic explosions, emission from deep within our galaxy, and supermassive black holes buried within host galaxies.The VLASS was proposed in 2014 by our community-led Survey Science Group (SSG). VLASS Pilot observations were taken in mid-2016, and the first epoch covering half the area (VLASS1.1) commenced in September 2017. The raw data from the VLASS are available in the NRAO archive immediately with no proprietary period. The Basic Data Products (BDP) that will be produced by the survey team are public and will additionally include: calibrated visibility data, quick-look continuum images (with a goal of posting to the archive within 1 week of observation), single-epoch and cumulative combined-epoch images, spectral image cubes, and basic object catalogs. Single-epoch and cumulative images are in intensity and linear polarization (Stokes IQU). In addition to the BDP provided by NRAO and served through the NRAO archive, there are plans for Enhanced Data Products and Services to be provided by the community in partnership with the

  9. Radiative forcing by aerosols as derived from the AeroCom present-day and pre-industrial simulations

    Directory of Open Access Journals (Sweden)

    M. Schulz

    2006-01-01

    Full Text Available Nine different global models with detailed aerosol modules have independently produced instantaneous direct radiative forcing due to anthropogenic aerosols. The anthropogenic impact is derived from the difference of two model simulations with prescribed aerosol emissions, one for present-day and one for pre-industrial conditions. The difference in the solar energy budget at the top of the atmosphere (ToA yields a new harmonized estimate for the aerosol direct radiative forcing (RF under all-sky conditions. On a global annual basis RF is −0.22 Wm−2, ranging from +0.04 to −0.41 Wm−2, with a standard deviation of ±0.16 Wm−2. Anthropogenic nitrate and dust are not included in this estimate. No model shows a significant positive all-sky RF. The corresponding clear-sky RF is −0.68 Wm−2. The cloud-sky RF was derived based on all-sky and clear-sky RF and modelled cloud cover. It was significantly different from zero and ranged between −0.16 and +0.34 Wm−2. A sensitivity analysis shows that the total aerosol RF is influenced by considerable diversity in simulated residence times, mass extinction coefficients and most importantly forcing efficiencies (forcing per unit optical depth. The clear-sky forcing efficiency (forcing per unit optical depth has diversity comparable to that for the all-sky/ clear-sky forcing ratio. While the diversity in clear-sky forcing efficiency is impacted by factors such as aerosol absorption, size, and surface albedo, we can show that the all-sky/clear-sky forcing ratio is important because all-sky forcing estimates require proper representation of cloud fields and the correct relative altitude placement between absorbing aerosol and clouds. The analysis of the sulphate RF shows that long sulphate residence times are compensated by low mass extinction coefficients and vice versa. This is explained by more sulphate particle humidity growth and thus higher extinction in those models where short-lived sulphate

  10. Design and creating model and interactive presentation of GEM for Microcosm Exhibition

    CERN Document Server

    Lakdee, Natthaphop

    2017-01-01

    GEM or Gas Electron Multiplier is the newer and easier way to amplify electron signal than conventional CSS. It was first created by Fabio Sauli at CERN in 1997 and was developed to get better efficiency over time. Right now, it was brought to use in many detector stations at CERN. To make GEM more publicly known, one of the ways is show in Microcosm Exhibition which is always visited by people from around the world everyday, so my main project as summer student is to design and create the model and interactive presentation which make GEM interesting and easy to understand by ordinary people.

  11. The Biggest Star in the Sky

    Science.gov (United States)

    1997-03-01

    years. This title has now been taken by R Doradus. R Doradus is a variable star in the constellation of Dorado (the Swordfish), located in the far southern sky. At a distance of about 200 light years it is relatively nearby. R Doradus is a variable star with a period of about 338 days, changing its magnitude from approximately 4.8 at maximum (when it is visible with the unaided eye) to 6.6 at minimum (when it requires a small telescope). Interferometry at the NTT In August 1993, the team of astronomers [1] pointed the ESO 3.5-metre New Technology Telescope (NTT) towards R Doradus. For these observations, the NTT was covered with an opaque mask with seven holes arranged on a 3.3-metre diameter circle. Each of these holes had a diameter of 25 cm, which was smaller than the cells of turbulence in the atmosphere above. The main motivation for using the mask was to suppress the effects of the turbulence and in this way restore the full resolution capability of the NTT [2]. Caption to ESO PR Photo 07/97 [JPG, 63k] The seven light beams from a star were brought to interfere with each other at the telescope's focus. Each pair of holes in the mask produced a fringe pattern in the image of the star, so at any moment there were 21 distinct fringe patterns (see ESO Press Photo 07/97 [63k] ). A camera in the focal plane recorded these fringes, their contrast being determined during subsequent computer analysis. A star which is very far away will appear too small for its disk to be resolved by the telescope. All of the 21 fringes will then have approximately the same contrast. On the other hand, if the star is closer by and has a perceptible size, the contrast of the fringe patterns will be reduced for widely separate mask holes. By comparing the fringe contrast of the target star with that of a more distant, unresolved star, it is then possible to estimate the size of the target. The present NTT observations were made at infrared wavelengths (1.25 microns) with the SHARP camera

  12. The spectral amplification effect of clouds to the night sky radiance in Madrid

    Science.gov (United States)

    Aubé, M.; Kocifaj, M.; Zamorano, J.; Solano Lamphar, H. A.; Sanchez de Miguel, A.

    2016-09-01

    Artificial Light at Night (ALAN) may have various environmental impacts ranging from compromising the visibility of astronomical objects to the perturbation of circadian cycles in animals and humans. In the past much research has been carried out to study the impact of ALAN on the radiance of the night sky during clear sky conditions. This was mainly justified by the need for a better understanding of the behavior of ALAN propagation into the environment in order to protect world-class astronomical facilities. More recently, alongside to the threat to the natural starry sky, many issues have emerged from the biological science community. It has been shown that, nearby or inside cities, the presence of cloud cover generally acts as an amplifier for artificial sky radiance while clouds behave as attenuators for remote observers. In this paper we show the spectral behavior of the zenith sky radiance amplification factor exerted by clouds inside a city. We compare in-situ measurements made with the spectrometer SAND-4 with a numerical model applied to the specific geographical context of the Universidad Complutense de Madrid in Spain.

  13. Hydrological Modeling in Northern Tunisia with Regional Climate Model Outputs: Performance Evaluation and Bias-Correction in Present Climate Conditions

    Directory of Open Access Journals (Sweden)

    Asma Foughali

    2015-07-01

    Full Text Available This work aims to evaluate the performance of a hydrological balance model in a watershed located in northern Tunisia (wadi Sejnane, 378 km2 in present climate conditions using input variables provided by four regional climate models. A modified version (MBBH of the lumped and single layer surface model BBH (Bucket with Bottom Hole model, in which pedo-transfer parameters estimated using watershed physiographic characteristics are introduced is adopted to simulate the water balance components. Only two parameters representing respectively the water retention capacity of the soil and the vegetation resistance to evapotranspiration are calibrated using rainfall-runoff data. The evaluation criterions for the MBBH model calibration are: relative bias, mean square error and the ratio of mean actual evapotranspiration to mean potential evapotranspiration. Daily air temperature, rainfall and runoff observations are available from 1960 to 1984. The period 1960–1971 is selected for calibration while the period 1972–1984 is chosen for validation. Air temperature and precipitation series are provided by four regional climate models (DMI, ARP, SMH and ICT from the European program ENSEMBLES, forced by two global climate models (GCM: ECHAM and ARPEGE. The regional climate model outputs (precipitation and air temperature are compared to the observations in terms of statistical distribution. The analysis was performed at the seasonal scale for precipitation. We found out that RCM precipitation must be corrected before being introduced as MBBH inputs. Thus, a non-parametric quantile-quantile bias correction method together with a dry day correction is employed. Finally, simulated runoff generated using corrected precipitation from the regional climate model SMH is found the most acceptable by comparison with runoff simulated using observed precipitation data, to reproduce the temporal variability of mean monthly runoff. The SMH model is the most accurate to

  14. Modeling past, present, and future basal ice amounts in the snowpack at a High Arctic site

    Science.gov (United States)

    Kohler, J.; van Pelt, W.

    2016-12-01

    Winter snow is a key factor affecting many aspects of polar ecosystems. Snowpack thickness, and ice layers formed within and, particularly, at the base of the snowpack, have all been linked to fluctuations in High Arctic animal populations in Svalbard. In northwestern Svalbard, measurements of snow properties have been made along a series of transects around the peninsula Brøggerhalvøya annually since 2002. Measurements are made over a 1-2 day period in April/May, with soundings made at 100-200 m intervals along transects, and snow pits dug at regular intervals to determine the snowpack stratigraphy, in particular the basal ice layer thickness. In 2010, 2012 and 2015, extreme winter warm periods, with temperatures well above freezing, led to the formation of a pervasive ground-ice layer, whose average was 10 cm thick or more across low-lying terrain around the peninsula. Here we present the results from a model used to simulate the winter snowpack and, more importantly, the development of the ice layer at the base of the snowpack. The model couples a surface energy balance model to a multilayer snow model simulating vertical evolution of density, temperature and water content, accounting for percolation, refreezing, storage and water runoff, and to a soil model to simulate heat conduction beneath the snowpack. Forcing is provided by data from nearby meteorological station data, and covers the period 1969-2016. The model is calibrated to the snowpack measurements around the peninsula, and is able to successfully simulate the significant icing events of the past decades, both those measured since 2002 and earlier events that were noted by biologists working in the area. We evaluate the development of the winter snowpack under future climate warming scenarios by performing a temperature sensitivity analysis. We rerun the model holding all meteorological forcing parameters constant except for temperature. We adjust temperature non-linearly to simulate the changes

  15. Presenting the students’ academic achievement causal model based on goal orientation

    Directory of Open Access Journals (Sweden)

    EBRAHIM NASIRI

    2017-10-01

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

  16. Presenting a conceptual model of data collection to manage the groundwater quality

    Directory of Open Access Journals (Sweden)

    Nourbakhsh Zahra

    2017-12-01

    Full Text Available A conceptual model was proposed in the present study, which highlighted important independent and dependent variables in order to managing the groundwater quality. Furthermore, the methods of selection of variable and collection of related data were explained. The study was carried out in the Tajan Plain, north of Iran; 50 drinking wells were considered as sampling points. In this model the Analytical Hierarchy Process (AHP was proposed to select the indicator water quality parameters. According to expert opinions and characteristics of the study area ten factors were chosen as variables influencing the quality of groundwater (land use types, lithology units, geology units, distance of wells to the outlet, distance to the residential areas, direction toward the residential areas, depth of the groundwater table, the type of aquifer, transmissivity and population. Geographic Information System (AecGIS 9.3 was used to manage the spatial-based variables and the data of non-spatial-based variables were obtained from relevant references. A database, which contains all collected data related to groundwater quality management in the studied area, was created as the output of the model. The output of this conceptual model can be used as an input for quantitative and mathematical models. Results show that 6 parameters (sulphate, iron, nitrate, electrical conductivity, calcium, and total dissolved solids (TDS were the best indicators for groundwater quality analysis in the area. More than 50% of the wells were drilled in the depth of groundwater table about 5 meters, in this low depth pollutants can load into the wells and also 78% of the wells are located within 5 km from the urban area; it can be concluded from this result that the intensive urban activities could affect groundwater quality.

  17. The Automatic Recognition of the Abnormal Sky-subtraction Spectra Based on Hadoop

    Science.gov (United States)

    An, An; Pan, Jingchang

    2017-10-01

    The skylines, superimposing on the target spectrum as a main noise, If the spectrum still contains a large number of high strength skylight residuals after sky-subtraction processing, it will not be conducive to the follow-up analysis of the target spectrum. At the same time, the LAMOST can observe a quantity of spectroscopic data in every night. We need an efficient platform to proceed the recognition of the larger numbers of abnormal sky-subtraction spectra quickly. Hadoop, as a distributed parallel data computing platform, can deal with large amounts of data effectively. In this paper, we conduct the continuum normalization firstly and then a simple and effective method will be presented to automatic recognize the abnormal sky-subtraction spectra based on Hadoop platform. Obtain through the experiment, the Hadoop platform can implement the recognition with more speed and efficiency, and the simple method can recognize the abnormal sky-subtraction spectra and find the abnormal skyline positions of different residual strength effectively, can be applied to the automatic detection of abnormal sky-subtraction of large number of spectra.

  18. Night Sky preservation and restoration in U.S. National Parks

    Science.gov (United States)

    Duriscoe, Dan M.; Ament, Nate

    2015-08-01

    The U.S. National Park Service (NPS) Night Skies Program contributes to the recognition of certain outstanding NPS lands as dark sky places. A combination of efforts including measuring resource condition, within-park outdoor lighting control, education outreach for visitors, and engagement with surrounding communities helps establish and maintain such places. In certain circumstances, communities and protected areas join forces in a cooperative effort to preserve the natural nocturnal environment of a region. One recent example, the Colorado Plateau Dark Sky Cooperative, is taking lighting, conservation, and educational steps to fulfill the mission of the NPS Call To Action- Starry Starry Night. This voluntary initiative forms America’s first Dark Sky Cooperative, and links communities, tribes, businesses, state/federal agencies, and citizens in a collaborative effort to celebrate the view of the cosmos, minimize the impact of outdoor lighting, and ultimately restore natural darkness to the area. We[AN1] present progress and accomplishments of established dark sky parks and reserves in the western U.S., with particular emphasis on public response to the actions taken and the results achieved.

  19. COSMO-SkyMed an existing opportunity for observing the Earth

    Science.gov (United States)

    F. Covello; Battazza, F.; Coletta, A.; Lopinto, E.; Fiorentino, C.; Pietranera, L.; Valentini, G.; Zoffoli, S.

    2010-04-01

    COnstellation of small Satellites for Mediterranean basin Observation (COSMO-SkyMed) is the largest Italian investment in Space Systems for Earth Observation, commissioned and funded by Italian Space Agency (ASI) and Italian Ministry of Defence (MoD). COSMO-SkyMed is a Dual-Use (Civilian and Defence) end-to-end Earth Observation System aimed at establishing a global service supplying provision of data, products and services compliant with well-established international standards and relevant to a wide range of applications, such as Risk Management, Scientific and Commercial Applications and Defence Applications. The system consists of a constellation of four LEO mid-sized satellites, each equipped with a multi-mode high-resolution SAR operating at X-band. Three out of four COSMO-SkyMed satellites have been successfully launched the 8th of June, the 9th of December 2007 and the 25th of October 2008 respectively, while the remaining satellite will be deployed within 2010. COSMO-SkyMed 1 and 2 completed their commissioning phase to test, verify and qualify the overall system and from the 1st of August 2008 both satellites are in the operational phase. The third satellite is still performing its commissioning and it is expected to enter in operation in the second half of 2009. The results of the commissioning phase of COSMO-SkyMed 1 and 2 are presented together with the Scientific Mission Exploitation strategy (i.e. Announcement of Opportunity, Background Mission).

  20. Derivation of Sky-View Factors from LIDAR Data

    Science.gov (United States)

    Kidd, Christopher; Chapman, Lee

    2013-01-01

    The use of Lidar (Light Detection and Ranging), an active light-emitting instrument, is becoming increasingly common for a range of potential applications. Its ability to provide fine resolution spatial and vertical resolution elevation data makes it ideal for a wide range of studies. This paper demonstrates the capability of Lidar data to measure sky view factors (SVF). The Lidar data is used to generate a spatial map of SVFs which are then compared against photographically-derived SVF at selected point locations. At each location three near-surface elevations measurements were taken and compared with collocated Lidar-derived estimated. It was found that there was generally good agreement between the two methodologies, although with decreasing SVF the Lidar-derived technique tended to overestimate the SVF: this can be attributed in part to the spatial resolution of the Lidar sampling. Nevertheless, airborne Lidar systems can map sky view factors over a large area easily, improving the utility of such data in atmospheric and meteorological models.

  1. Parametric Modeling of Urban Landscape: Decoding the Brasilia of Lucio Costa from Modernism to Present Days

    Directory of Open Access Journals (Sweden)

    Ana Clara Moura

    2014-05-01

    Full Text Available The paper presents the case study of the Pilot-Plan of Brasilia, important example of modernist urban design protected as human heritage. Discusses a methodological process to promote visualization of maximum envelops of urban volumes, organized in a set of rules and scripts which structures urban parameters in a logic of volume constructions. Applies City Engine - ESRI facilities to construct and visualize the urban rules. It has the goal to promote characterization, analysis, proposals and simulation of urban parameters in order to support decision making in land use transformation. The research deals with the difficulties of management urban pressure of transformation and the maintenance of urban cultural heritage. The methodology defends the change from authorial urban design to the decoding of collective values and goals. The 3D modeling and dynamic visualization promotes the composition of the whole, which means to work in a relative mode, and not in an absolute sense. Although it had been developed for a particular case study, the protected historical area of Brasilia, it presents methodological processes of how to structure rules of three-dimensional modeling to simulate the maximum constructive authorized by planning legislation (maximum envelopes, so that it can be reapplied in any other situation of definition of parameters in urban master plans and in laws for land use and occupation.

  2. Geographical Information System Model for Potential Mines Data Management Presentation in Kabupaten Gorontalo

    Science.gov (United States)

    Roviana, D.; Tajuddin, A.; Edi, S.

    2017-03-01

    Mining potential in Indonesian is very abundant, ranging from Sabang to Marauke. Kabupaten Gorontalo is one of many places in Indonesia that have different types of minerals and natural resources that can be found in every district. The abundant of mining potential must be balanced with good management and ease of getting information by investors. The current issue is, (1) ways of presenting data/information about potential mines area is still manually (the maps that already capture from satellite image, then printed and attached to information board in the office) it caused the difficulties of getting information; (2) the high cost of maps printing; (3) the difficulties of regency leader (bupati) to obtain information for strategic decision making about mining potential. The goal of this research is to build a model of Geographical Information System that could provide data management of potential mines, so that the investors could easily get information according to their needs. To achieve that goal Research and Development method is used. The result of this research, is a model of Geographical Information System that implemented in an application to presenting data management of mines.

  3. Simulation of present-day precipitation over India using a regional climate model

    Science.gov (United States)

    Maurya, Rajesh Kumar Singh; Singh, G. P.

    2016-04-01

    The objective of the present paper is to examine the capability of the regional climate model version 3 (RegCM3) to simulate the annual as well as seasonal precipitation variability over the Indian subcontinent. RegCM3 has been run at 40 km horizontal resolution for the period of 1982-2006 continuously and model results were compared to the observed precipitation datasets of India Meteorological Department (IMD) and CPC Merged Analysis of Precipitation (CMAP). Model evaluation has been done using different statistical methods like mean bias error (MBE), root mean square error, mean percentage error (MPE) and studied the spatial pattern of annual and seasonal variability and trend. Daily precipitation data at 1° × 1° grids of IMD have been used to study observed climatological means (both annual and seasonal), regression trends, interannual and intraseasonal variability over India from 1951 to 2007. The spatial distribution of annual precipitation shows a decreasing trend over west coast of India, central India, hilly region of India and an increasing trend is found over the northwest India, peninsular India and northeast India. The temporal distribution of daily precipitation shows highest rainfall of 18 mm/day in mid July (in composite flood cases only) and 12 mm/day during August (in composite drought cases only). The RegCM3 simulated annual and seasonal precipitation variability is close to the observed IMD and CMAP over all India (AI). During winter and pre-monsoon season, the model has overestimated the mean precipitation while underestimated in summer and post-monsoon season. Overall, annual precipitation showed the deficiency of -22.44 % compared to IMD and -1.41 % compared to CMAP over India. To understand the possible cause of annual and seasonal precipitation biases over India and its six homogeneous regions, the vertical difference (model mines National Centre for Environmental Prediction; NCEP) fields of water vapor mixing ratio (WVMR) and air

  4. Brightness map of the zodiacal emission from the AKARI IRC All-Sky Survey

    Science.gov (United States)

    Pyo, J.; Ueno, M.; Kwon, S. M.; Hong, S. S.; Ishihara, D.; Ishiguro, M.; Usui, F.; Ootsubo, T.; Mukai, T.

    2010-11-01

    The first Japanese infrared space mission AKARI successfully scanned the whole sky with its two main instruments, the Infrared Camera (IRC) and the Far-Infrared Surveyor (FIS). The AKARI All-Sky Survey provides us with an invaluable opportunity to examine the zodiacal emission (ZE) over the entire sky in the leading as well as the trailing direction of the Earth's motion. We describe our efforts to reduce the ZE brightness map from the AKARI's survey in the 9 μm waveband. Compared with the interplanetary dust cloud model of Kelsall et al. (1998), the map requires an increase of the contribution of the resonance ring component to the ZE brightness by about 20%. We paid special attention to the north and south ecliptic pole brightnesses. The symmetry plane's inclination and longitude of ascending node need to be modified from those in Kelsall et al. (1998) to reach a best fit to the observed pole brightness difference.

  5. Battery Ownership Model: A Tool for Evaluating the Economics of Electrified Vehicles and Related Infrastructure (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, M.; Brooker, A.; Johnson, C.; Mendelsohn, M.; Neubauer, J.; Pesaran, A.

    2010-11-01

    This presentation uses a vehicle simulator and economics model called the Battery Ownership Model to examine the levelized cost per mile of conventional (CV) and hybrid electric vehicles (HEVs) in comparison with the cost to operate an electric vehicle (EV) under a service provider business model. The service provider is assumed to provide EV infrastructure such as charge points and swap stations to allow an EV with a 100-mile range to operate with driving profiles equivalent to CVs and HEVs. Battery cost, fuel price forecast, battery life, and other variables are examined to determine under what scenarios the levelized cost of an EV with a service provider can approach that of a CV. Scenarios in both the United States as an average and Hawaii are examined. The levelized cost of operating an EV with a service provider under average U.S. conditions is approximately twice the cost of operating a small CV. If battery cost and life can be improved, in this study the cost of an EV drops to under 1.5 times the cost of a CV for U.S. average conditions. In Hawaii, the same EV is only slightly more expensive to operate than a CV.

  6. A model presented for classification ECG signals base on Case-Based Reasoning

    Directory of Open Access Journals (Sweden)

    Elaheh Sayari

    2013-07-01

    Full Text Available Early detection of heart diseases/abnormalities can prolong life and enhance the quality of living through appropriate treatment; thus classifying cardiac signals will be helped to immediate diagnosing of heart beat type in cardiac patients. The present paper utilizes the case base reasoning (CBR for classification of ECG signals. Four types of ECG beats (normal beat, congestive heart failure beat, ventricular tachyarrhythmia beat and atrial fibrillation beat obtained from the PhysioBank database was classified by the proposed CBR model. The main purpose of this article is classifying heart signals and diagnosing the type of heart beat in cardiac patients that in proposed CBR (Case Base Reasoning system, Training and testing data for diagnosing and classifying types of heart beat have been used. The evaluation results from the model are shown that the proposed model has high accuracy in classifying heart signals and helps to clinical decisions for diagnosing the type of heart beat in cardiac patients which indeed has high impact on diagnosing the type of heart beat aided computer.

  7. The Sky in your Hands - From the planetarium to the classroom

    Science.gov (United States)

    Canas, L.; Borges, I.; Ortiz-Gil, A.

    2013-09-01

    "The sky in your hands" is a project created in 2009, during the International Year of Astronomy in Spain, with the goal to create an image of the Universe for the visually impaired audiences. Includes a planetarium show with an audio component and tactile semi - spheres where the public can touch constellations and other objects of the Universe. Following the spirit of the IYA2009, the authors of this project made all products available to everyone that wishes to use them in outreach activities and science education. From observation and analyses of several groups of students and teachers that visited "The sky in your hands" Portuguese adaptation in Lisbon Planetarium, our team concluded that much could be done in classroom with students to make their process of learning easier and more motivating. Additionally it was noticed that for some schools it was difficult to travel with students to visit the planetarium. With this experience in mind different resources and materials were adapted to be used in classroom. Through this adaptation all students including those visually impaired can build a simple tactile image of a constellation and, working in small groups, can use low cost, recycled materials to build these tactile models. Students can record a new audio file explaining the astronomical concepts of the model they have built and include the m in a story. The groups include visually impaired and non-visually impaired students, as different skills from different students complete each other in order to accomplish the task in a more successful way. Afterwards each group presents the work to their peers. With this poster we plan to share our experience with the community where the collaboration between informal science learning in science centers, museums or planetariums and formal learning in school improves science learning, inspires students and facilitates their understanding of the nature of science in general.

  8. Aladin Lite: Embed your Sky in the Browser

    Science.gov (United States)

    Boch, T.; Fernique, P.

    2014-05-01

    I will introduce and describe Aladin Lite1, a lightweight interactive sky viewer running natively in the browser. The past five years have seen the emergence of powerful and complex web applications, thanks to major improvements in JavaScript engines and the advent of HTML5. At the same time, browser plugins Java applets, Flash, Silverlight) that were commonly used to run rich Internet applications are declining and are not well suited for mobile devices. The Aladin team took this opportunity to develop Aladin Lite, a lightweight version of Aladin geared towards simple visualization of a sky region. Relying on the widely supported HTML5 canvas element, it provides an intuitive user interface running on desktops and tablets. This first version allows one to interactively visualize multi-resolution HEALPix image and superimpose tabular data and footprints. Aladin Lite is easily embeddable on any web page and may be of interest for data providers which will be able to use it as an interactive previewer for their own image surveys, previously pre-processed as explained in details in the poster "Create & publish your Hierarchical Progressive Survey". I will present the main features of Aladin Lite as well as the JavaScript API which gives the building blocks to create rich interactions between a web page and Aladin Lite.

  9. DESCQA: An Automated Validation Framework for Synthetic Sky Catalogs

    Science.gov (United States)

    Mao, Yao-Yuan; Kovacs, Eve; Heitmann, Katrin; Uram, Thomas D.; Benson, Andrew J.; Campbell, Duncan; Cora, Sofía A.; DeRose, Joseph; Di Matteo, Tiziana; Habib, Salman; Hearin, Andrew P.; Bryce Kalmbach, J.; Krughoff, K. Simon; Lanusse, François; Lukić, Zarija; Mandelbaum, Rachel; Newman, Jeffrey A.; Padilla, Nelson; Paillas, Enrique; Pope, Adrian; Ricker, Paul M.; Ruiz, Andrés N.; Tenneti, Ananth; Vega-Martínez, Cristian A.; Wechsler, Risa H.; Zhou, Rongpu; Zu, Ying; The LSST Dark Energy Science Collaboration

    2018-02-01

    The use of high-quality simulated sky catalogs is essential for the success of cosmological surveys. The catalogs have diverse applications, such as investigating signatures of fundamental physics in cosmological observables, understanding the effect of systematic uncertainties on measured signals and testing mitigation strategies for reducing these uncertainties, aiding analysis pipeline development and testing, and survey strategy optimization. The list of applications is growing with improvements in the quality of the catalogs and the details that they can provide. Given the importance of simulated catalogs, it is critical to provide rigorous validation protocols that enable both catalog providers and users to assess the quality of the catalogs in a straightforward and comprehensive way. For this purpose, we have developed the DESCQA framework for the Large Synoptic Survey Telescope Dark Energy Science Collaboration as well as for the broader community. The goal of DESCQA is to enable the inspection, validation, and comparison of an inhomogeneous set of synthetic catalogs via the provision of a common interface within an automated framework. In this paper, we present the design concept and first implementation of DESCQA. In order to establish and demonstrate its full functionality we use a set of interim catalogs and validation tests. We highlight several important aspects, both technical and scientific, that require thoughtful consideration when designing a validation framework, including validation metrics and how these metrics impose requirements on the synthetic sky catalogs.

  10. Rapid All-Sky Transient Discovery and Analysis with Evryscope

    Science.gov (United States)

    Corbett, Henry T.; Law, Nicholas; Fors, Octavi; Ratzloff, Jeff; Goeke, Erin; Howard, Ward S.

    2018-01-01

    The Evryscope is an array of 24 small telescopes on a common mount, capable of observing the entire visible sky down to g' ~ 16 with a two-minute cadence. Each exposure covers 8000 square degrees over 691 MPix and requires minimal readout time, providing 97% continuous coverage of the night sky. The system's large field of view and rapid cadence enable exploration of a previously inaccessible parameter space of bright and fast transients, including nearby microlensing events, supernovae, and kilonovae GW counterparts. The first instrument, located at CTIO in Chile, was deployed in mid-2015 and is currently in production creating multi-year light curves with percent-level precision. A second identical system is on track for deployment at Mount Laguna Observatory in California in early 2018. Once operational, the two sites will provide simultaneous two-color photometry over a 4000 square degree overlapping region accessible to both instruments, operating as a combined discovery and follow-up network for transient phenomena on all nearby stars and many nearby galaxies. I will present recent science results from the Evryscope and an overview of our data reduction pipeline.

  11. Sky and Elemental Planetary Mapping Via Gamma Ray Emissions

    Science.gov (United States)

    Roland, John M.

    2011-01-01

    Low-energy gamma ray emissions ((is) approximately 30keV to (is) approximately 30MeV) are significant to astrophysics because many interesting objects emit their primary energy in this regime. As such, there has been increasing demand for a complete map of the gamma ray sky, but many experiments to do so have encountered obstacles. Using an innovative method of applying the Radon Transform to data from BATSE (the Burst And Transient Source Experiment) on NASA's CGRO (Compton Gamma-Ray Observatory) mission, we have circumvented many of these issues and successfully localized many known sources to 0.5 - 1 deg accuracy. Our method, which is based on a simple 2-dimensional planar back-projection approximation of the inverse Radon transform (familiar from medical CAT-scan technology), can thus be used to image the entire sky and locate new gamma ray sources, specifically in energy bands between 200keV and 2MeV which have not been well surveyed to date. Samples of these results will be presented. This same technique can also be applied to elemental planetary surface mapping via gamma ray spectroscopy. Due to our method's simplicity and power, it could potentially improve a current map's resolution by a significant factor.

  12. Introduction to the Arizona Sky Island Arthropod Project (ASAP): Systematics, Biogeography, Ecology, and Population Genetics of Arthropods of the Madrean Sky Islands.

    Science.gov (United States)

    Moore, Wendy; Meyer, Wallace M; Eble, Jeffrey A; Franklin, Kimberly; Wiens, John F; Brusca, Richard C

    2013-01-01

    The Arizona Sky Island Arthropod Project (ASAP) is a new multi-disciplinary research program at the University of Arizona that combines systematics, biogeography, ecology, and population genetics to study origins and patterns of arthropod diversity along elevation gradients and among mountain ranges in the Madrean Sky Island Region. Arthropods represent taxonomically and ecologically diverse organisms that drive key ecosystem processes in this mountain archipelago. Using data from museum specimens and specimens we obtain during long-term collecting and monitoring programs, ASAP will document arthropod species across Arizona's Sky Islands to address a number of fundamental questions about arthropods of this region. Baseline data will be used to determine climatic boundaries for target species, which will then be integrated with climatological models to predict future changes in arthropod communities and distributions in the wake of rapid climate change. ASAP also makes use of the natural laboratory provided by the Sky Islands to investigate ecological and genetic factors that influence diversification and patterns of community assembly. Here, we introduce the project, outline overarching goals, and describe preliminary data from the first year of sampling ground-dwelling beetles and ants in the Santa Catalina Mountains.

  13. Introduction to the Arizona Sky Island Arthropod Project (ASAP): Systematics, Biogeography, Ecology, and Population Genetics of Arthropods of the Madrean Sky Islands

    Science.gov (United States)

    Moore, Wendy; Meyer, Wallace M.; Eble, Jeffrey A.; Franklin, Kimberly; Wiens, John F.; Brusca, Richard C.

    2014-01-01

    The Arizona Sky Island Arthropod Project (ASAP) is a new multi-disciplinary research program at the University of Arizona that combines systematics, biogeography, ecology, and population genetics to study origins and patterns of arthropod diversity along elevation gradients and among mountain ranges in the Madrean Sky Island Region. Arthropods represent taxonomically and ecologically diverse organisms that drive key ecosystem processes in this mountain archipelago. Using data from museum specimens and specimens we obtain during long-term collecting and monitoring programs, ASAP will document arthropod species across Arizona's Sky Islands to address a number of fundamental questions about arthropods of this region. Baseline data will be used to determine climatic boundaries for target species, which will then be integrated with climatological models to predict future changes in arthropod communities and distributions in the wake of rapid climate change. ASAP also makes use of the natural laboratory provided by the Sky Islands to investigate ecological and genetic factors that influence diversification and patterns of community assembly. Here, we introduce the project, outline overarching goals, and describe preliminary data from the first year of sampling ground-dwelling beetles and ants in the Santa Catalina Mountains. PMID:25505938

  14. A model study of present-day Hall-effect circulators

    Energy Technology Data Exchange (ETDEWEB)

    Placke, B. [RWTH Aachen University, Institute for Quantum Information, Aachen (Germany); Bosco, S. [RWTH Aachen University, Institute for Quantum Information, Aachen (Germany); Juelich-Aachen Research Alliance (JARA), Fundamentals of Future Information Technologiesh, Juelich (Germany); DiVincenzo, D.P. [RWTH Aachen University, Institute for Quantum Information, Aachen (Germany); Juelich-Aachen Research Alliance (JARA), Fundamentals of Future Information Technologiesh, Juelich (Germany); Peter Gruenberg Institute, Theoretical Nanoelectronics, Forschungszentrum Juelich, Juelich (Germany)

    2017-12-15

    Stimulated by the recent implementation of a three-port Hall-effect microwave circulator of Mahoney et al. (MEA), we present model studies of the performance of this device. Our calculations are based on the capacitive-coupling model of Viola and DiVincenzo (VD). Based on conductance data from a typical Hall-bar device obtained from a two-dimensional electron gas (2DEG) in a magnetic field, we numerically solve the coupled field-circuit equations to calculate the expected performance of the circulator, as determined by the S parameters of the device when coupled to 50Ω ports, as a function of frequency and magnetic field. Above magnetic fields of 1.5 T, for which a typical 2DEG enters the quantum Hall regime (corresponding to a Landau-level filling fraction ν of 20), the Hall angle θ{sub H} = tan{sup -1} σ{sub xy}/σ{sub xx} always remains close to 90 , and the S parameters are close to the analytic predictions of VD for θ{sub H} = π/2. As anticipated by VD, MEA find the device to have rather high (kΩ) impedance, and thus to be extremely mismatched to 50Ω, requiring the use of impedance matching. We incorporate the lumped matching circuits of MEA in our modeling and confirm that they can produce excellent circulation, although confined to a very small bandwidth. We predict that this bandwidth is significantly improved by working at lower magnetic field when the Landau index is high, e.g. ν = 20, and the impedance mismatch is correspondingly less extreme. Our modeling also confirms the observation of MEA that parasitic port-to-port capacitance can produce very interesting countercirculation effects. (orig.)

  15. Predicting Clear-Sky Reflectance Over Snow/Ice in Polar Regions

    Science.gov (United States)

    Chen, Yan; Sun-Mack, Sunny; Arduini, Robert F.; Hong, Gang; Minnis, Patrick

    2015-01-01

    Satellite remote sensing of clouds requires an accurate estimate of the clear-sky radiances for a given scene to detect clouds and aerosols and to retrieve their microphysical properties. Knowing the spatial and angular variability of clear-sky albedo is essential for predicting clear-sky radiance at solar wavelengths. The Clouds and the Earth's Radiant Energy System (CERES) Project uses the nearinfrared (NIR; 1.24, 1.6 or 2.13 micrometers), visible (VIS; 0.63 micrometers) and vegetation (VEG; 0.86 micrometers) channels available on the Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) to help identify clouds and retrieve their properties in both snow-free and snow-covered conditions. Thus, it is critical to have reliable distributions of clear-sky albedo for all of these channels. In CERES Edition 4 (Ed4), the 1.24-micrometer channel is used to retrieve cloud optical depth over snow/ice-covered surfaces. Thus, it is especially critical to accurately predict the 1.24-micrometer clear-sky albedo alpha and reflectance rho for a given location and time. Snow albedo and reflectance patterns are very complex due to surface texture, particle shapes and sizes, melt water, and vegetation protrusions from the snow surface. To minimize those effects, this study focuses on the permanent snow cover of Antarctica where vegetation is absent and melt water is minimal. Clear-sky albedos are determined as a function of solar zenith angle (SZA) from observations over all scenes determined to be cloud-free to produce a normalized directional albedo model (DRM). The DRM is used to develop alpha(SZA=0 degrees) on 10 foot grid for each season. These values provide the basis for predicting r at any location and set of viewing & illumination conditions. This paper examines the accuracy of this approach for two theoretical snow surface reflectance models.

  16. Coherently combining short data segments for all-sky semi-coherent continuous gravitational wave searches

    CERN Document Server

    Goetz, Evan

    2015-01-01

    We present a method for coherently combining short data segments from gravitational-wave detectors to improve the sensitivity of semi-coherent searches for continuous gravitational waves. All-sky searches for continuous gravitational waves from unknown sources are computationally limited. The semi-coherent approach reduces the computational cost by dividing the entire observation timespan into short segments to be analyzed coherently, then combined together incoherently. Semi-coherent analyses that attempt to improve sensitivity by coherently combining data from multiple detectors face a computational challenge in accounting for uncertainties in signal parameters. In this article, we lay out a technique to meet this challenge using summed Fourier transform coefficients. Applying this technique to one all-sky search algorithm called TwoSpect, we confirm that the sensitivity of all-sky, semi-coherent searches can be improved by coherently combining the short data segments. For misaligned detectors, however, thi...

  17. Search for neutrino point sources with an all-sky autocorrelation analysis in IceCube

    Energy Technology Data Exchange (ETDEWEB)

    Turcati, Andrea; Bernhard, Anna; Coenders, Stefan [TU, Munich (Germany); Collaboration: IceCube-Collaboration

    2016-07-01

    The IceCube Neutrino Observatory is a cubic kilometre scale neutrino telescope located in the Antarctic ice. Its full-sky field of view gives unique opportunities to study the neutrino emission from the Galactic and extragalactic sky. Recently, IceCube found the first signal of astrophysical neutrinos with energies up to the PeV scale, but the origin of these particles still remains unresolved. Given the observed flux, the absence of observations of bright point-sources is explainable with the presence of numerous weak sources. This scenario can be tested using autocorrelation methods. We present here the sensitivities and discovery potentials of a two-point angular correlation analysis performed on seven years of IceCube data, taken between 2008 and 2015. The test is applied on the northern and southern skies separately, using the neutrino energy information to improve the effectiveness of the method.

  18. Sloan Digital Sky Survey Photometric Calibration Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Marriner, John; /Fermilab

    2012-06-29

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  19. The stargazer's guide to the night sky

    CERN Document Server

    Lisle, Jason, Dr

    2012-01-01

    Explore the night sky, identify stars, constellations, and even planets. Stargaze with a telescope, binoculars, or even your naked eye. Allow Dr. Jason Lisle, a research scientist with a masters and PhD in astrophysics, to guide you in examining the beauty of God's Creation with 150 full color star-charts. Learn the best ways and optimal times to observe planets and stars with easy to use illustrations. Create or expand the hobby of stargazing; an outdoor, educational hobby to enjoy with friends or family.

  20. Vanilla Sky – El cuento del narcisista

    OpenAIRE

    Graham St. John STOTT

    2016-01-01

    Vanilla Sky (2001), de Cameron Crowe, normalmente se aprecia como un juego intelectual; no obstante, su temática es mucho más oscura que lo que dicha etiqueta podría sugerir. Mientras recorre las diferentes fases del sueño de David Aames (un sueño en el que se mueve de una pretensión de amor a una de homicidio), nos damos cuenta de que David padece un trastorno de la autoestima. Utilizando como referencia Atracción Fatal (1987), de Adrian Lyne, para demostrar la incapacidad de tener en cuenta...

  1. The SPHEREx All-Sky Spectral Survey

    Science.gov (United States)

    Bock, James; SPHEREx Science Team

    2018-01-01

    SPHEREx, a mission in NASA's Medium Explorer (MIDEX) program that was selected for Phase A in August 2017, is an all-sky survey satellite designed to address all three science goals in NASA's astrophysics division, with a single instrument, a wide-field spectral imager. SPHEREx will probe the physics of inflation by measuring non-Gaussianity by studying large-scale structure, surveying a large cosmological volume at low redshifts, complementing high-z surveys optimized to constrain dark energy. The origin of water and biogenic molecules will be investigated in all phases of planetary system formation - from molecular clouds to young stellar systems with protoplanetary disks - by measuring ice absorption spectra. We will chart the origin and history of galaxy formation through a deep survey mapping large-scale spatial power in two deep fields located near the ecliptic poles. Following in the tradition of all-sky missions such as IRAS, COBE and WISE, SPHEREx will be the first all-sky near-infrared spectral survey. SPHEREx will create spectra (0.75 – 4.2 um at R = 41; and 4.2 – 5 um at R = 135) with high sensitivity making background-limited observations using a passively-cooled telescope with a wide field-of-view for large mapping speed. During its two-year mission, SPHEREx will produce four complete all-sky maps that will serve as a rich archive for the astronomy community. With over a billion detected galaxies, hundreds of millions of high-quality stellar and galactic spectra, and over a million ice absorption spectra, the archive will enable diverse scientific investigations including studies of young stellar systems, brown dwarfs, high-redshift quasars, galaxy clusters, the interstellar medium, asteroids and comets. All aspects of the instrument and spacecraft have high heritage. SPHEREx requires no new technologies and carries large technical and resource margins on every aspect of the design. SPHEREx is a partnership between Caltech and JPL, following the

  2. Night-sky brightness monitoring in Hong Kong - a city-wide light pollution assessment

    OpenAIRE

    Pun, Chun Shing Jason; So, Chu Wing

    2011-01-01

    Results of the first comprehensive light pollution survey in Hong Kong are presented. The night-sky brightness was measured and monitored around the city using a portable light sensing device called the Sky Quality Meter over a 15-month period beginning in March 2008. A total of 1,957 data sets were taken at 199 distinct locations, including urban and rural sites covering all 18 Administrative Districts of Hong Kong. The survey shows that the environmental light pollution problem in Hong Kong...

  3. The changing radiative forcing of fires: global model estimates for past, present and future

    Directory of Open Access Journals (Sweden)

    D. S. Ward

    2012-11-01

    Full Text Available Fires are a global phenomenon that impact climate and biogeochemical cycles, and interact with the biosphere, atmosphere and cryosphere. These impacts occur on a range of temporal and spatial scales and are difficult to quantify globally based solely on observations. Here we assess the role of fires in the climate system using model estimates of radiative forcing (RF from global fires in pre-industrial, present day, and future time periods. Fire emissions of trace gases and aerosols are derived from Community Land Model simulations and then used in a series of Community Atmosphere Model simulations with representative emissions from the years 1850, 2000, and 2100. Additional simulations are carried out with fire emissions from the Global Fire Emission Database for a present-day comparison. These results are compared against the results of simulations with no fire emissions to compute the contribution from fires. We consider the impacts of fire on greenhouse gas concentrations, aerosol effects (including aerosol effects on biogeochemical cycles, and land and snow surface albedo. Overall, we estimate that pre-industrial fires were responsible for a RF of −1 W m−2 with respect to a pre-industrial climate without fires. The largest magnitude pre-industrial forcing from fires was the indirect aerosol effect on clouds (−1.6 W m−2. This was balanced in part by an increase in carbon dioxide concentrations due to fires (+0.83 W m−2. The RF of fires increases by 0.5 W m−2 from 1850 to 2000 and 0.2 W m−2 from 1850 to 2100 in the model representation from a combination of changes in fire activity and changes in the background environment in which fires occur, especially increases and decreases in the anthropogenic aerosol burden. Thus, fires play an important role in both the natural equilibrium climate and the climate perturbed by anthropogenic activity and need to be considered in future

  4. Geometric modelling of channel present in reservoir petroleum using Bezier splines; Modelagem da geometria de paleocanais presentes em reservatorios petroliferos usando splines de Bezier

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Carlos Eduardo S. [Universidade Federal de Campina Grande, PB (Brazil). Programa de Recursos Humanos 25 da ANP]. E-mail: carlos@dme.ufcg.edu.br; Silva, Rosana M. da [Universidade Federal de Campina Grande, PB (Brazil). Dept. de Matematica e Estatistica]. E-mail: rosana@dme.ufcg.edu.br

    2004-07-01

    This work presents an implementation of a synthetic model of a channel found in oil reservoir. The generation these models is one of the steps to the characterization and simulation of the equal probable three-dimensional geological scenery. O implemented model was obtained from fitting techniques of geometric modeling of curves and surfaces to the geological parameters (width, thickness, sinuosity and preferential direction) that defines the form to be modeled. The parameter sinuosity is related with the parameter wave length and the local amplitude of the channel, the parameter preferential direction indicates the way of the flow and the declivity of the channel. The modeling technique used to represent the surface of the channel is the sweeping technique, the consist in effectuate a translation operation from a curve along a guide curve. The guide curve, in our implementation, was generated by the interpolation of points obtained form sampled values or simulated of the parameter sinuosity, using the cubic splines of Bezier technique. A semi-ellipse, determinate by the parameter width and thickness, representing a transversal section of the channel, is the transferred curve through the guide curve, generating the channel surface. (author)

  5. Investigating the Effective Factors on Entering into International Markets by Presenting the Local Islamic Model

    Directory of Open Access Journals (Sweden)

    Sayyed Mohammad Ali Alamolhodaei

    2015-03-01

    Full Text Available The internationalization of small and medium size businesses is regarded as one of the most leading general policies in many of the world’s countries. The reason is that it is often the small and medium size companies which have a vital role in industrial innovation and gain profit for their societies through economic development. This research has investigated and identified the effective factors (organizational factors and business etiquette in Islam on entering into international markets by presenting local Islamic model in the companies of incubator of Science and Technology Park. The statistical population of the research includes the existing companies of Incubator of Mashhad Science and Technology Park. The statistical sample was investigated through simple random sampling from managers of active companies in export in Science and Technology Park. AMOS and SPSS software were applied for data analysis to identify the effects among variables survey research methodology and questionnaire tools were used.

  6. Promoter or enhancer, what's the difference? Deconstruction of established distinctions and presentation of a unifying model.

    Science.gov (United States)

    Andersson, Robin

    2015-03-01

    Gene transcription is strictly controlled by the interplay of regulatory events at gene promoters and gene-distal regulatory elements called enhancers. Despite extensive studies of enhancers, we still have a very limited understanding of their mechanisms of action and their restricted spatio-temporal activities. A better understanding would ultimately lead to fundamental insights into the control of gene transcription and the action of regulatory genetic variants involved in disease. Here, I review and discuss pros and cons of state-of-the-art genomics methods to localize and infer the activity of enhancers. Among the different approaches, profiling of enhancer RNAs yields the highest specificity and may be superior in detecting in vivo activity. I discuss their apparent similarities to promoters, which challenge the established view of enhancers and promoters as distinct entities, and present a unifying model of regulatory elements in transcriptional regulation, in which activity, transcriptional output and regulatory function is context specific. © 2015 WILEY Periodicals, Inc.

  7. Modeling ultrafast laser-induced nanocavitation around plasmonic nanoparticles (Conference Presentation)

    Science.gov (United States)

    Meunier, Michel; Dagallier, Adrien; Lachaine, Rémi; Boutopoulos, Christos; Boulais, Étienne

    2017-03-01

    Vapor nanobubbles generated around plasmonic nanoparticles (NPs) by ultrafast laser irradiation are efficient for inducing localized damage to living cells. Killing targeted cancer cells or gene delivery can therefore be envisioned using this new technology [1,2]. The extent of the damage and its non-lethal character are linked to the size of the nanobubble. Precise understanding of the mechanisms leading to bubble formation around plasmonic nanostructures is necessary to optimize the technique. In this presentation, we present a complete model that successfully describes all interactions occurring during the irradiation of plasmonics nanostructures by an ultrafast laser of various pulse widths and fluences. Nanoavitation is caused by the interplay between heat conduction at the NP-medium interface and non-linear plasmon-enhanced photoionization of a nanoplasma in the near-field [3-5], the former being dominant for in-resonance and the latter for off-resonance irradiation. Modeling of the whole laser-nanoparticle interaction, together with the help of the shadowgraphic imaging and scattering techniques [3-5], give valuable insight on the mechanisms of cavitation at the nanoscale, leading to possible optimization of the nanostructure for bubble-based nanomedicine applications. 1- E. Boulais, R. Lachaine, A. Hatef, and M. Meunier, Journal of Photochemistry and Photobiology C: Photochemistry Reviews 17, 26-49 (2013). 2- E. Bergeron, S. Patskovsky, D. Rioux, and M. Meunier, Nanoscale 7,17836-17847 (2015). 3- E. Boulais, R. Lachaine, and M. Meunier, Nano Letters 12, 4763-4769 (2012). 4- R. Lachaine, E. Boulais, and M. Meunier, ACS Photonics 1, 331-336 (2014). 5- C. Boutopoulos, A. Hatef, M. Fortin-Deschênes, and M. Meunier Nanoscale 7,11758-11765 (2015).

  8. ISOCT study of collagen crosslinking of collagen in cancer models (Conference Presentation)

    Science.gov (United States)

    Spicer, Graham; Young, Scott T.; Yi, Ji; Shea, Lonnie D.; Backman, Vadim

    2016-03-01

    The role of extracellular matrix modification and signaling in cancer progression is an increasingly recognized avenue for the progression of the disease. Previous study of field effect carcinogenesis with Inverse Spectroscopic Optical Coherence Tomography (ISOCT) has revealed pronounced changes in the nanoscale-sensitive mass fractal dimension D measured from field effect tissue when compared to healthy tissue. However, the origin of this difference in tissue ultrastructure in field effect carcinogenesis has remained poorly understood. Here, we present findings supporting the idea that enzymatic crosslinking of the extracellular matrix is an effect that presents at the earliest stages of carcinogenesis. We use a model of collagen gel with crosslinking induced by lysyl oxidase (LOXL4) to recapitulate the difference in D previously reported from healthy and cancerous tissue biopsies. Furthermore, STORM imaging of this collagen gel model verifies the morphologic effects of enzymatic crosslinking at length scales as small as 40 nm, close to the previously reported lower length scale sensitivity threshold of 35 nm for ISOCT. Analysis of the autocorrelation function from STORM images of collagen gels and subsequent fitting to the Whittle-Matérn correlation function shows a similar effect of LOXL4 on D from collagen measured with ISOCT and STORM. We extend this to mass spectrometric study of tissue to directly measure concentrations of collagen crosslink residues. The validation of ISOCT as a viable tool for non-invasive rapid quantification of collagen ultrastructure lends it to study other physiological phenomena involving ECM restructuring such as atherosclerotic plaque screening or cervical ripening during pregnancy.

  9. Lung respiration motion modeling: a sparse motion field presentation method using biplane x-ray images

    Science.gov (United States)

    Chen, Dong; Xie, Hongzhi; Zhang, Shuyang; Gu, Lixu

    2017-10-01

    Respiration-introduced tumor location uncertainty is a challenge in the precise lung biopsy for lung lesions. Current statistical modeling approaches hardly capture the complex local respiratory motion information. In this study, we formulate a statistical respiratory motion model using biplane x-ray images to improve the accuracy of motion field estimation by efficiently preserving local motion details for specific patients. Given CT data sets of 18 healthy subjects at end-expiratory and end-inspiratory breathing phases, the respiratory motion field is constructed based on deformation vector fields which are extracted from these CT data sets, and a lung contour motion repository respiratory is generated dependent on displacements of boundary control points. By varying the sparse weight coefficients of the statistical sparse motion field presentation (SMFP) method, the newly-input motion field is approximately presented by a sparse linear combination of a subset of the motion repository. The SMFP method is employed twice in the coefficient optimization process. Finally, these non-zero coefficients are fine-tuned to maximize the similarity between the projection image of reconstructed volumetric images and the current x-ray image. We performed the proposed method for estimating respiratory motion field on ten subject datasets and compared the result with the PCA method. The maximum average target registration error of the PCA-based and the SMFP-based respiratory motion field estimation are 3.1(2.0) and 2.9(1.6) mm, respectively. The maximum average symmetric surface distance of two methods are 2.5(1.6) and 2.4(1.3) mm, respectively.

  10. SkyMine Carbon Mineralization Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Joe Jones; Clive Barton; Mark Clayton; Al Yablonsky; David Legere

    2010-09-30

    This Topical Report addresses accomplishments achieved during Phase 1 of the SkyMine{reg_sign} Carbon Mineralization Pilot Project. The primary objectives of this project are to design, construct, and operate a system to capture CO{sub 2} from a slipstream of flue gas from a commercial coal-fired cement kiln, convert that CO{sub 2} to products having commercial value (i.e., beneficial use), show the economic viability of the CO{sub 2} capture and conversion process, and thereby advance the technology to a point of readiness for commercial scale demonstration and proliferation. The project will also substantiate market opportunities for the technology by sales of chemicals into existing markets, and identify opportunities to improve technology performance and reduce costs at commercial scale. The primary objectives of Phase 1 of the project were to elaborate proven SkyMine{reg_sign} process chemistry to commercial pilot-scale operation and complete the preliminary design ('Reference Plant Design') for the pilot plant to be built and operated in Phase 2. Additionally, during Phase 1, information necessary to inform a DOE determination regarding NEPA requirements for the project was developed, and a comprehensive carbon lifecycle analysis was completed. These items were included in the formal application for funding under Phase 2. All Phase 1 objectives were successfully met on schedule and within budget.

  11. Intercomparisons of Nine Sky Brightness Detectors

    Directory of Open Access Journals (Sweden)

    Henk Spoelstra

    2011-10-01

    Full Text Available Nine Sky Quality Meters (SQMs have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across the Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between ±14%. Individual night time sums range from −16% to +20%. Intercalibration reduces this to 0.5%, and −7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 ± 0.003 mcd/m2 on 12 April, and the largest value was 5.94 ± 0.03 mcd/m2 on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent.

  12. SkyMine Carbon Mineralization Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Christenson, Norm; Walters, Jerel

    2014-12-31

    This Topical Report addresses accomplishments achieved during Phase 2b of the SkyMine® Carbon Mineralization Pilot Project. The primary objectives of this project are to design, construct, and operate a system to capture CO2 from a slipstream of flue gas from a commercial coal-fired cement kiln, convert that CO2 to products having commercial value (i.e., beneficial use), show the economic viability of the CO2 capture and conversion process, and thereby advance the technology to the point of readiness for commercial scale demonstration and deployment. The overall process is carbon negative, resulting in mineralization of CO2 that would otherwise be released into the atmosphere. The project will also substantiate market opportunities for the technology by sales of chemicals into existing markets, and identify opportunities to improve technology performance and reduce costs at the commercial scale. The project is being conducted in two phases. The primary objectives of Phase 1 were to evaluate proven SkyMine® process chemistry for commercial pilot-scale operation and complete the preliminary design for the pilot plant to be built and operated in Phase 2, complete a NEPA evaluation, and develop a comprehensive carbon life cycle analysis. The objective of Phase 2b was to build the pilot plant to be operated and tested in Phase 2c.

  13. Petyarre and Moffat: 'Looking from the Sky'

    Directory of Open Access Journals (Sweden)

    Linnell Secomb

    2013-08-01

    Full Text Available Moffatt’s Up in the Sky series draws attention to the relation between sky and earth, through the content and camera angles of the images. Similarly, Kathleen Petyarre’s Central Desert acrylic dot painting evokes this relation representing country and Dreaming from a celestial perspective—as she says ‘looking from the sky’. Yet here any association between these artists seems to end with the urban artist refusing to engage Aboriginal tradition and the desert artist focused on Dreaming, country and heritage. However, a further connection between these disparate works may also be discerned as each, in differing ways, transforms our conventional perceptions of space and time. Reading these images in relation to Walter Benjamin’s concepts of the auratic and of messianic time, I suggest that each restructures dimension and duration putting in question the (postmodern calibrations of our space/time experience. This paper stages an engagement between these artists’ works and Benjamin’s concepts exploring the variations and modifications of the spatial and the temporal that hybrid cross-cultural exchanges require and facilitate.

  14. Deep sky observing an astronomical tour

    CERN Document Server

    Coe, Steven R

    2016-01-01

    This updated second edition has all of the information needed for your successful forays into deep sky observing. Coe uses his years of experience to give detailed practical advice about how to find the best observing site, how to make the most of the time spent there, and what equipment and instruments to take along. There are comprehensive lists of deep sky objects of all kinds, along with Steve's own observations describing how they look through telescopes with apertures ranging from 4 inches to 36 inches (0.1 - 0.9 meters). Binocular observing also gets its due, while the lists of objects have been amended to highlight only the best targets. A new index makes finding targets easier than ever before, while the selection of viewing targets has been revised from the first edition. Most of all, this book is all about how to enjoy astronomy. The author's enthusiasm and sense of wonder shine through every page as he invites you along on a tour of some of the most beautiful and fascinating sites in the deep ...

  15. COSMO-SkyMed and GIS applications

    Science.gov (United States)

    Milillo, Pietro; Sole, Aurelia; Serio, Carmine

    2013-04-01

    Geographic Information Systems (GIS) and Remote Sensing have become key technology tools for the collection, storage and analysis of spatially referenced data. Industries that utilise these spatial technologies include agriculture, forestry, mining, market research as well as the environmental analysis . Synthetic Aperture Radar (SAR) is a coherent active sensor operating in the microwave band which exploits relative motion between antenna and target in order to obtain a finer spatial resolution in the flight direction exploiting the Doppler effect. SAR have wide applications in Remote Sensing such as cartography, surface deformation detection, forest cover mapping, urban planning, disasters monitoring , surveillance etc… The utilization of satellite remote sensing and GIS technology for this applications has proven to be a powerful and effective tool for environmental monitoring. Remote sensing techniques are often less costly and time-consuming for large geographic areas compared to conventional methods, moreover GIS technology provides a flexible environment for, analyzing and displaying digital data from various sources necessary for classification, change detection and database development. The aim of this work si to illustrate the potential of COSMO-SkyMed data and SAR applications in a GIS environment, in particular a demostration of the operational use of COSMO-SkyMed SAR data and GIS in real cases will be provided for what concern DEM validation, river basin estimation, flood mapping and landslide monitoring.

  16. SOUTH POL: Revealing the Polarized Southern Sky

    Science.gov (United States)

    Magalhaes, Antonio Mario Mario; Ramírez, Edgar; Ribeiro, Nadili; Seriacopi, Daiane; Rubinho, Marcelo; Ferrari, Tiberio; Rodrigues, Claudia; Schoenell, William; Herpich, Fabio; Pereyra, Antonio

    2018-01-01

    SOUTH POL will be a survey of the Southern sky in optical polarized light. It will use a newly built polarimeter for T80-S, an 84 cm robotic telescope installed at Cerro Tololo (CTIO), Chile. It will initially cover the sky South of declination -15 deg with a polarimetric accuracy < 0.1% at V~14-15. The telescope and camera combination covers a field of about 2.0 square degrees.SOUTH POL will impact areas such as Cosmology, Extragalactic Astronomy, Interstellar Medium of the Galaxy and Magellanic Clouds, Star Formation, Stellar Envelopes, Stellar Explosions and Solar System.The polarimeter has just been commissioned in mid-November, 2017. The data reduction pipeline has already been built. We will describe the instrument and the data reduction, as well as a few of the science cases. The survey is expected to begin midway through the 1st semester of 2018. Both catalog data and raw images will be made available.

  17. A water balance model for Saxonian catchments - present state and projections up to 2100

    Science.gov (United States)

    Winkler, Peter; Hauffe, Corina; Baldy, Agnes; Schwarze, Robert

    2014-05-01

    The impact of climate change on the regional water balance regime may have severe consequences for agriculture, forestry and water resources management. In this respect the following questions arise: Will extensive irrigation be necessary on Saxonian crop land in future? Which are the necessary adaptions in water resources management? Are new agricultural and forestry concepts necessary? Therefore, the project KliWES aims at modelling the present water balance regime for whole Saxonia (with the exception of the mining regions and the Elbe-corridor which is largely governed by flood events). Moreover, the effects of climate projections from the WetReg model (CEC) on the water balance regime have been investigated. The calibration strategy relies on splitting up the measured discharges into the major water balance components (evaporation, surface flow, subsurface flow and percolation) by a geometrical analysis of the hydrograph (DIFGA, Schwarze et al.). Thereafter, the water balance software ArcEGMO (Pfützner et al.) has been calibrated on these water balance components. Calibration parameters include correction factors for soil macroporosity, evapo-transpiration and the distribution factor between fast and slow groundwater components. Geological and Soil data have been drawn from official databases (LfULG). Subareas where no continuous gauge data are available have been parametrised by a regionalisation procedure relying on correlations between parameters and physical properties of the subareas considered. Possibilities and limitations of such a regionalisation procedure have been pointed out. Focal point of the present study is an investigation of water balance components in different spatial and temporal resolutions. The Results of the model for the climate projections show drastic increase of evaporation and decrease of groundwater recharge especially in the north-eastern parts of Saxonia (Lausitz). Here, this problem is worsened by the predominantly sandy soils

  18. Using routine meteorological data to derive sky conditions

    Directory of Open Access Journals (Sweden)

    D. Pagès

    2003-03-01

    Full Text Available Sky condition is a matter of interest for public and weather predictors as part of weather analyses. In this study, we apply a method that uses total solar radiation and other meteorological data recorded by an automatic station for deriving an estimation of the sky condition. The impetus of this work is the intention of the Catalan Meteorological Service (SMC to provide the public with real-time information about the sky condition. The methodology for deriving sky conditions from meteorological records is based on a supervised classification technique called maximum likelihood method. In this technique we first need to define features which are derived from measured variables. Second, we must decide which sky conditions are intended to be distinguished. Some analyses have led us to use four sky conditions: (a cloudless or almost cloudless sky, (b scattered clouds, (c mostly cloudy – high clouds, (d overcast – low clouds. An additional case, which may be treated separately, corresponds to precipitation (rain or snow. The main features for estimating sky conditions are, as expected, solar radiation and its temporal variability. The accuracy of this method of guessing sky conditions compared with human observations is around 70% when applied to four sites in Catalonia (NE Iberian Peninsula. The agreement increases if we take into account the uncertainty both in the automatic classifier and in visual observations.Key words. Meteorological and atmospheric dynamics (instruments and techniques; radiative processes – Atmospheric composition and structure (cloud physics and chemistry

  19. Sky type discrimination using a ground-based sun photometer

    Science.gov (United States)

    DeFelice, Thomas P.; Wylie, Bruce K.

    2001-01-01

    A 2-year feasibility study was conducted at the USGS EROS Data Center, South Dakota (43.733°N, 96.6167°W) to assess whether a four-band, ground-based, sun photometer could be used to discriminate sky types. The results indicate that unique spectral signatures do exist between sunny skies (including clear and hazy skies) and cirrus, and cirrostratus, altocumulus or fair-weather cumulus, and thin stratocumulus or altostratus, and fog/fractostratus skies. There were insufficient data points to represent other cloud types at a statistically significant level.

  20. Short time-scale variability in the Faint Sky Variability Survey

    NARCIS (Netherlands)

    Morales-Rueda, L.; Groot, P.J.; Augusteijn, T.; Nelemans, G.A.; Vreeswijk, P.M.; Besselaar, E.J.M. van den

    2006-01-01

    We present the V-band variability analysis of the point sources in the Faint Sky Variability Survey on time-scales from 24 min to tens of days. We find that about one per cent of the point sources down to V = 24 are variables. We discuss the variability-detection probabilities for each field

  1. The Cosmic Lens All-Sky Survey parent population : I. Sample selection and number counts

    NARCIS (Netherlands)

    McKean, J. P.; Browne, I. W. A.; Jackson, N. J.; Fassnacht, C. D.; Helbig, P.

    We present the selection of the Jodrell Bank Flat-spectrum (JBF) radio source sample, which is designed to reduce the uncertainties in the Cosmic Lens All-Sky Survey (CLASS) gravitational lensing statistics arising from the lack of knowledge about the parent population luminosity function. From

  2. All-sky search for short gravitational-wave bursts in the first Advanced LIGO run

    NARCIS (Netherlands)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Phythian-Adams, A.T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.T.; Aguiar, O. D.; Aiello, L.; Ain, A.; Allen, B.; Allocca, A.; Altin, P. A.; Ananyeva, A.; Anderson, S. B.; Anderson, W. G.; Appert, S.; Arai, K.; Araya, M. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Avila-Alvarez, A.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, R.D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Beer, C.; Bejger, M.; Belahcene, I.; Belgin, M.; Bell, A. S.; Berger, B. K.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Billman, C. R.; Birch, M.J.; Birney, R.; Birnholtz, O.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blackman, J.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, A.L.S.; Bock, O.; Boer, M.; Bogaert, J.G.; Bohe, A.; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Broida, J. E.; Brooks, A. F.; Brown, A.D.; Brown, D.; Brown, N. M.; Brunett, S.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cabero, M.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Bustillo, J. Calderon; Callister, T. A.; Calloni, E.; Camp, J. B.; Canepa, M.; Cannon, K. C.; Cao, H.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Diaz, J. Casanueva; Casentini, C.; Caudill, S.; Cavaglia, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Baiardi, L. Cerboni; Cerretani, G.; Cesarini, E.; Chamberlin, S. J.; Chan, M.; Chao, D. S.; Charlton, P.; Chassande-Mottin, E.; Cheeseboro, B. D.; Chen, H. Y.; Chen, Y; Cheng, H. -P.; Chincarini, A.; Chiummo, A.; Chmiel, T.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Qian; Chua, A. J. K.; Chua, S. E.; Chung, E.S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Cocchieri, C.; Coccia, E.; Cohadon, P. -F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M., Jr.; Conti, L.; Cooper, S. J.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, A.C.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J. -P.; Countryman, S. T.; Couvares, P.; Covas, P. B.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Creighton, J. D. E.; Creighton, T. D.; Cripe, J.; Crowder, S. G.; Cullen, T. J.; Cumming, A.; Cunningham, A.L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Dasgupta, A.; Costa, C. F. Da Silva; Dattilo, V.; Dave, I.; Davier, M.; Davies, G. S.; Davis, D.; Daw, E. J.; Day, B.; Day, R.; De, S.; Debra, D.; Debreczeni, G.; Degallaix, J.; De laurentis, M.; Deleglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dergachev, V.A.; Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Devenson, J.; Devine, R. C.; Dhurandhar, S.; Diaz, M. C.; Di Fiore, L.; Giovanni, M.G.; Di Girolamo, T.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Doctor, Z.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Dorrington, I.; Douglas, R.; Alvarez, M. Dovale; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H. -B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Eisenstein, R. A.; Essick, R. C.; Etienne, Z.; Etzel, T.; Evans, M.C.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.M.; Farinon, S.; Farr, B.; Farr, W. M.; Fauchon-Jones, E. J.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Galiana, A. Fernandez; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M; Fong, H.; Forsyth, S. S.; Fournier, J. -D.; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fries, E. M.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H.; Gadre, B. U.; Gaebel, S. M.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gaur, G.; Gayathri, V.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghonge, S.; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.P.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; Gonzalez, R.G.; Castro, J. M. Gonzalez; Gopakumar, A.; Gorodetsky, M. L.; Gossan, S. E.; Lee-Gosselin, M.; Gouaty, R.; Grado, A.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.M.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Buffoni-Hall, R.; Hall, E. D.; Hammond, G.L.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hanson, P.J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C. -J.; Haughian, K.; Healy, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Henry, J.A.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hofman, D.; Holt, K.; Holz, D. E.; Hopkins, P.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J. -M.; Isi, M.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jimenez-Forteza, F.; Johnson, W.; Jones, I.D.; Jones, R.; Jonker, R. J. G.; Ju, L.; Junker, J.; Kalaghatgi, C. V.; Kandhasamy, S.; Kang, G.H.; Kanner, J. B.; Karki, S.; Karvinen, K. S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kefelian, F.; Keitel, D.; Kelley, D. B.; Kennedy, R.E.; Key, J. S.; Khalili, F. Y.; Khan, I.; Khan., S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, Chunglee; Kim, J. C.; Kim, Whansun; Kim, W.; Kim, Y.M.; Kimbrell, S. J.; King, E. J.; King, P. J.; Kirchhoff, R.; Kissel, J. S.; Klein, B.; Kleybolte, L.; Klimenko, S.; Koch, P.; Koehlenbeck, S. M.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kraemer, H.C.; Kringel, V.; Krishnan, B.; Krolak, A.; Kuehn, G.; Kumar, P.; Kumar, R.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lang, R. N.; Lange, J.; Lantz, B.; Lanza, R. K.; Lartaux-Vollard, A.; Lasky, P. D.; Laxen, M.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C.H.; Lee, K.H.; Lee, M.H.; Lee, K.; Lehmann, J.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Liu, J.; Lockerbie, N. A.; Lombardi, A. L.; London, L. T.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lovelace, G.; Luck, H.; Lundgren, A. P.; Lynch, R.; Ma, Y.; Macfoy, S.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magana-Sandoval, F.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Marka, S.; Marka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martynov, D. V.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Mastrogiovanni, S.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGrath Hoareau, C.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McRae, T.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mendoza-Gandara, D.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Metzdorff, R.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, A. L.; Miller, F.A.; Miller, B.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B.C.; Moore, J.C.; Moraru, D.; Gutierrez Moreno, M.; Morriss, S. R.; Mours, B.; Mow-Lowry, C. M.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, S.D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Muniz, E. A. M.; Murray, P.G.; Mytidis, A.; Napier, K.; Nardecchia, I.; Naticchioni, L.; Nelemans, G.; Nelson, T. J. N.; Gutierrez-Neri, M.; Nery, M.; Neunzert, A.; Newport, J. M.; Newton-Howes, G.; Nguyen, T. T.; Nissanke, S.; Nitz, A.; Noack, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; Oelker, E.; Ogin, G. H.; Oh, J.; Oh, S. H.; Ohme, F.; Oliver, M. B.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Overmier, H.; Owen, B. J.; Pace, A. E.; Page, J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.S; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Castro-Perez, J.; Perreca, A.; Perri, L. M.; Pfeiffer, H. P.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poe, M.; Poggiani, R.; Popolizio, P.; Post, A.; Powell, J.; Prasad, J.; Pratt, J. W. W.; Predoi, V.; Prestegard, T.; Prijatelj, M.; Principe, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L. G.; Puncken, O.; Punturo, M.; Puppo, P.; Puerner, M.; Qi, H.; Qin, J.; Qiu, S.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rajan, C.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Rhoades, E.; Ricci, F.; Riles, K.; Rizzo, D.M.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, R.; Romie, J. H.; Rosinska, D.; Rowan, S.; Ruediger, A.; Ruggi, P.; Ryan, K.A.; Sachdev, P.S.; Sadecki, T.; Sadeghian, L.; Sakellariadou, M.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sampson, L. M.; Sanchez, E. J.; Sandberg, V.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O.; Savage, R. L.; Sawadsky, A.; Schale, P.; Scheuer, J.; Schmidt, E.; Schmidt, J; Schmidt, P.; Schnabel, R.B.; Schofield, R. M. S.; Schoenbeck, A.; Schreiber, K.E.C.; Schuette, D.; Schutz, B. F.; Schwalbe, S. G.; Scott, J.; Scott, M.S.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Setyawati, Y.; Shaddock, D. A.; Shaffer, T. J.; Shahriar, M. S.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sieniawska, M.; Sigg, D.; Silva, António Dias da; Singer, A; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, B.; Smith, J.R.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Spencer, A. P.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stevenson-Moore, P.; Stone, J.R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strigin, S. E.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sunil, S.; Sutton, P. J.; Swinkels, B. L.; Szczepanczyk, M. J.; Tacca, M.D.; Talukder, D.; Tanner, D. B.; Tapai, M.; Taracchini, A.; Taylor, W.R.; Theeg, T.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thrane, E.; Tippens, T.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Toland, K.; Tomlinson, C.; Tonelli, M.; Tornasi, Z.; Torrie, C. I.; Torya, D.; Travasso, F.; Traylor, G.; Trifiro, D.; Trinastic, J.; Tringali, M. C.; Trozzo, L.; Tse, M.; Tso, R.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; van Bakel, N.; van Beuzekom, M.G.; van den Brand, J. F. J.; Van Den Broeck, C.F.F.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Varma, V.; Vass, S.; Vasuth, M.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P.J.; Venkateswara, K.; Venugopalan, G.; Verkindt, D.; Vetrano, F.; Vicere, A.; Viets, A. D.; Vinciguerra, S.; Vine, D. J.; Vinet, J. -Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D. V.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, MT; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Watchi, J.; Weaver, B.; Wei, L. -W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Wen, L.M.; Wessels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; Whiting, B. F.; Whittle, C.; Williams, D.; Williams, D.R.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Woehler, J.; Worden, J.; Wright, J.L.; Wu, D.S.; Wu, G.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yap, M. J.; Yu, Hang; Yu, Haocun; Yvert, M.; Zadrozny, A.; Zangrando, L.; Zanolin, M.; Zendri, J. -P.; Zevin, M.; Zhang, L.; Zhang, M.; Zhang, T.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, S.J.; Zhu, X. J.; Zucker, M. E.; Zweizig, J.

    2017-01-01

    We present the results from an all-sky search for short-duration gravitational waves in the data of the first run of the Advanced LIGO detectors between September 2015 and January 2016. The search algorithms use minimal assumptions on the signal morphology, so they are sensitive to a wide range of

  3. Planck early results. VIII. The all-sky early Sunyaev-Zeldovich cluster sample

    DEFF Research Database (Denmark)

    Poutanen, T.; Natoli, P.; Polenta, G.

    2011-01-01

    We present the first all-sky sample of galaxy clusters detected blindly by the Planck satellite through the Sunyaev-Zeldovich (SZ) effect from its six highest frequencies. This early SZ (ESZ) sample is comprised of 189 candidates, which have a high signal-to-noise ratio ranging from 6 to 29. Its ...

  4. The Hipparcos, Tycho, TRC, and ACT catalogues - A whole sky comparison of the proper motions

    NARCIS (Netherlands)

    Hoogerwerf, R; Blaauw, A

    We present a whole sky comparison of the proper motions contained in the Hipparcos Catalogue, the Tycho Catalogue, the Tycho Reference Catalogue (TRC), and the Astro-graphic Catalogue plus Tycho Reference Catalogue (ACT). The catalogues are compared in the 20 declination zones defined by the

  5. The "Sky on Earth" Project: A Synergy between Formal and Informal Astronomy Education

    Science.gov (United States)

    Rossi, Sabrina; Giordano, Enrica; Lanciano, Nicoletta

    2016-01-01

    In this paper we present the "Sky on Earth" project funded in 2008 by the Italian Ministry of Instruction, Research and University, inside its annual public outreach education program. The project's goal was to realise a stable and open-access astronomical garden, where children, teachers and citizens could be engaged in investigations…

  6. A Comprehensive Approach to Dark Skies Research and Education at NOAO

    Science.gov (United States)

    Walker, Constance E.; Pompea, S. M.; Sparks, R. T.

    2013-01-01

    NOAO and its Education and Public Outreach group play an important role locally, nationally, and internationally in raising dark skies awareness. For the past 3 years NOAO has co-hosted the international “Earth and Sky” photo contest. In 2012 there were over 600 entries contributed within 3 weeks. NOAO also created a series of audio podcasts based on serial-type skits featuring a caped dark-skies hero who typically “saves the night” by mitigating upward directed lights with shields, thereby saving sea turtles, minimizing health effects, conserving energy, or keeping the public safe. To help understand the effects of light pollution, a citizen-science campaign called GLOBE at Night was started seven years ago. The worldwide campaign involves the public in recording night sky brightness data by matching the view of a constellation like Orion with maps of progressively fainter stars. Every year, NOAO adds more opportunities for participation: more campaigns during the year, Web applications for smart phones, objective measurements with sky brightness meters, and a GLOBE at Night Facebook page. Campaigns will run roughly the first 10 days of January through May in 2013. The EPO group created “Dark Skies Rangers”, a suite of well-tested and evaluated hands-on, minds-on activities that have children building star-brightness “readers,” creating glow-in-the-dark tracings to visualize constellations, and role-playing confused sea turtles. They also created a model city with shielded lights to stop upward light, examine different kinds of bulbs for energy efficiency, and perform an outdoor lighting audit of their school or neighborhood to determine ways to save energy. In the REU program at NOAO North, the undergraduate students have been doing research over the last 3 summers on effect of light pollution on endangered bats and characterizing the behavior of sky brightness over time across Tucson and on nearby astronomical mountaintops. For more information

  7. Disaggregation of remotely sensed soil moisture under all sky condition using machine learning approach in Northeast Asia

    Science.gov (United States)

    Kim, S.; Kim, H.; Choi, M.; Kim, K.

    2016-12-01

    Estimating spatiotemporal variation of soil moisture is crucial to hydrological applications such as flood, drought, and near real-time climate forecasting. Recent advances in space-based passive microwave measurements allow the frequent monitoring of the surface soil moisture at a global scale and downscaling approaches have been applied to improve the spatial resolution of passive microwave products available at local scale applications. However, most downscaling methods using optical and thermal dataset, are valid only in cloud-free conditions; thus renewed downscaling method under all sky condition is necessary for the establishment of spatiotemporal continuity of datasets at fine resolution. In present study Support Vector Machine (SVM) technique was utilized to downscale a satellite-based soil moisture retrievals. The 0.1 and 0.25-degree resolution of daily Land Parameter Retrieval Model (LPRM) L3 soil moisture datasets from Advanced Microwave Scanning Radiometer 2 (AMSR2) were disaggregated over Northeast Asia in 2015. Optically derived estimates of surface temperature (LST), normalized difference vegetation index (NDVI), and its cloud products were obtained from MODerate Resolution Imaging Spectroradiometer (MODIS) for the purpose of downscaling soil moisture in finer resolution under all sky condition. Furthermore, a comparison analysis between in situ and downscaled soil moisture products was also conducted for quantitatively assessing its accuracy. Results showed that downscaled soil moisture under all sky condition not only preserves the quality of AMSR2 LPRM soil moisture at 1km resolution, but also attains higher spatial data coverage. From this research we expect that time continuous monitoring of soil moisture at fine scale regardless of weather conditions would be available.

  8. The Past, Present, and Future of Computational Models of Cognitive Development

    Science.gov (United States)

    Schlesinger, Matthew; McMurray, Bob

    2012-01-01

    Does modeling matter? We address this question by providing a broad survey of the computational models of cognitive development that have been proposed and studied over the last three decades. We begin by noting the advantages and limitations of computational models. We then describe four key dimensions across which models of development can be…

  9. Sky dancer: the threshold of the buckling instability

    Science.gov (United States)

    Cros, Anne; Ibarra Nuño, Rodolfo; Michon, Bastien

    2012-11-01

    The sky dancer is a fabric-made large vertical tube which may ``dance'' above an air blower. We reproduced in laboratory reduced models, with diameters between 2.2 and 3 cm, and lengths varying from 45 to 95 cm. We measured the air speed and the pressure at the tube basis for the lower threshold of the tube. This threshold separates two regimes: the first one which appears for the lower velocities, when the tube falls down because of its own weight, from the second one, which corresponds to the stable regime, for which the tube stands up. Our measurements show that the air pressure thresholds get values equal to the pressure performed by the tube weight. We discuss our results and compare them with previous studies which dealt with thicker-walled tubes.

  10. USING OF NET PRESENT VALUE (NPV) TO TEST THE INTEGRATED MODEL IN BUILDING MANAGEMENT INFORMATION SYSTEMS

    OpenAIRE

    Omar, Mohammad; Abdullah, Khairul

    2017-01-01

    The integrated model is a new model that is recently developed in order to build the management information systems (MIS's) by using the classical approach system development methodology. The integrated model aims to address the drawbacks of the classical approach in consumption additional time and cost while building the MIS's. The integrated model was subjected to two tests by using the mathematical probability theories in order to ensure the validity of the integrated model in it...

  11. Towards artificial tissue models: past, present, and future of 3D bioprinting.

    Science.gov (United States)

    Arslan-Yildiz, Ahu; El Assal, Rami; Chen, Pu; Guven, Sinan; Inci, Fatih; Demirci, Utkan

    2016-03-01

    Regenerative medicine and tissue engineering have seen unprecedented growth in the past decade, driving the field of artificial tissue models towards a revolution in future medicine. Major progress has been achieved through the development of innovative biomanufacturing strategies to pattern and assemble cells and extracellular matrix (ECM) in three-dimensions (3D) to create functional tissue constructs. Bioprinting has emerged as a promising 3D biomanufacturing technology, enabling precise control over spatial and temporal distribution of cells and ECM. Bioprinting technology can be used to engineer artificial tissues and organs by producing scaffolds with controlled spatial heterogeneity of physical properties, cellular composition, and ECM organization. This innovative approach is increasingly utilized in biomedicine, and has potential to create artificial functional constructs for drug screening and toxicology research, as well as tissue and organ transplantation. Herein, we review the recent advances in bioprinting technologies and discuss current markets, approaches, and biomedical applications. We also present current challenges and provide future directions for bioprinting research.

  12. Past and present variability of the solar-terrestrial system: measurement, data analysis and theoretical models

    Energy Technology Data Exchange (ETDEWEB)

    Cini Castagnoli, G.; Provenzale, A. [eds.

    1997-12-31

    The course Past and present variability of the solar-terrestrial system: measurement, data analysis and theoretical models is explicitly devoted to these issues. A solar cycle ago, in summer 1985, G. Cini organized a similar school, in a time when this field was in a very early stage of development and definitely fewer high-quality measurements were available. After eleven years, the field has grown toward becoming a robust scientific discipline, new data have been obtained, and new ideas have been proposed by both solar physicists and climate dynamicists. For this reason, the authors felt that it was the right time to organize a new summer school, with the aim of formalizing the developments that have taken place during these years, and also for speculating and maybe dreaming of new results that will be achieved in the upcoming years. The papers of the lectures have now been collected in this volume. First, in order to know what the authors talking about, they need to obtain reliable data from terrestrial archives,and to properly date the records that have been measured. To these crucial aspects is devoted the first part of the book, dealing with various types of proxy data and with the difficult issue of the dating of the records.

  13. [Proposed difficult airway teaching methodology. Presentation of an interactive fresh frozen cadaver model].

    Science.gov (United States)

    Catalá Bauset, J C; de Andres Ibañez, J A; Valverde Navarro, A; Martinez Soriano, F

    2014-04-01

    The aim of this paper is to present a methodology based on the use of fresh-frozen cadavers for training in the management of the airway, and to evaluate the degree of satisfaction among learning physicians. About 6 fresh-frozen cadavers and 14 workstations were prepared where participants were trained in the different skills needed for airway management. The details of preparation of the cadavers are described. The level of satisfaction of the participant was determined using a Likert rating scale of 5 points, at each of the 14 stations, as well as the overall assessment and clinical usefulness of the course. The mean overall evaluation of the course and its usefulness was 4.75 and 4.9, out of 5, respectively. All parts of the course were rated above 4 out of 5. The high level of satisfaction of the course remained homogeneous in the 2 editions analysed. The overall satisfaction of the course was not finally and uniquely determined by any of its particular parts. The fresh cadaver model for training physicians in techniques of airway management is a proposal satisfactory to the participant, and with a realism that approaches the live patient. Copyright © 2013 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Published by Elsevier España. All rights reserved.

  14. Being present in action: a theoretical model about the interlocking between intentions and environmental affordances

    Directory of Open Access Journals (Sweden)

    Stefano eTriberti

    2016-01-01

    Full Text Available Recent neuropsychological evidence suggest that a key role in linking perceptions and intentions is played by sense of presence. Despite this phenomenon having been studied primarily in the field of virtual reality (conceived as the illusion of being in the virtual space, recent research highlighted that it is a fundamental feature of everyday experience. Specifically, the function of presence as a cognitive process is to locate the Self in a physical space or situation, based on the perceived possibility to act in it; so, the variations in sense of presence allow one to continuously adapt his own action to the external environment. Indeed intentions, as the cognitive antecedents of action, are not static representations of the desired outcomes, but dynamic processes able to adjust their own representational content according to the opportunities/restrictions emerging in the environment. Focusing on the peculiar context of action mediated by interactive technologies, we here propose a theoretical model showing how each level of an intentional hierarchy (future-directed; present directed; and motor intentions can interlock with environmental affordances in order to promote a continuous stream of action and activity.

  15. Novel Threadlike Structures May Be Present on the Large Animal Organ Surface: Evidence in Swine Model

    Directory of Open Access Journals (Sweden)

    Kyoung-Hee Bae

    2013-01-01

    Full Text Available Background. The types of embryonic development probably provoke different paths of novel threadlike structure (NTS development. The authors hypothesized that NTS may be easily observed on the surface of swine intestines by using trypan blue staining method and visualization under an optical microscope. Methods. General anesthesia was administered to 2 Yorkshire pigs. The abdominal walls of the pigs were carefully dissected along the medial alba. NTSs were identified on organ surfaces under a stereoscopic microscope after trypan blue staining. Isolated NTS specimens obtained from the large intestine were subjected to 4′,6-diamidino-2-phenylindole (DAPI staining and observed using the polarized light microscopy to confirm whether the obtained structure fits the definition of NTS. Results. We found elastic, semitransparent threadlike structures (forming a network structure that had a milky-white color in situ and in vivo in swine large intestines. The samples showed distinct extinction of polarized light at every 90 degrees, and nucleus was shown to be rod shaped by DAPI staining, indicating that they meet the criteria of NTS. Conclusion. We used a swine model to demonstrate that NTS may be present on large animal organ surfaces. Our results may permit similar studies by using human specimens.

  16. The global blue-sky albedo change between 2000 - 2015 seen from MODIS

    Science.gov (United States)

    Chrysoulakis, N.; Mitraka, Z.; Gorelick, N.

    2016-12-01

    The land surface albedo is a critical physical variable, which influences the Earth's climate by affecting the energy budget and distribution in the Earth-atmosphere system. Blue-sky albedo estimates provide a quantitative means for better constraining global and regional scale climate models. The Moderate Resolution Imaging Spectroradiometer (MODIS) albedo product includes parameters for the estimation of both the directional-hemispherical surface reflectance (black-sky albedo) and the bi-hemispherical surface reflectance (white-sky albedo). This dataset was used here for the blue-sky albedo estimation over the globe on an 8-day basis at 0.5 km spatial resolution for the whole time period covered by MODIS acquisitions (i.e. 2000 until today). To estimate the blue-sky albedo, the fraction of the diffused radiation is needed, a function of the Aerosol Optical Thickness (AOT). Required AOT information was acquired from the MODIS AOT product at 1̊ × 1̊ spatial resolution. Since the blue-sky albedo depends on the solar zenith angle (SZA), the 8-day mean blue-sky albedo values were computed as averages of the corresponding values for the representative SZAs covering the 24-hour day. The estimated blue-sky albedo time series was analyzed to capture changes during the 15 period. All computation were performed using the Google Earth Engine (GEE). The GEE provided access to all the MODIS products needed for the analysis without the need of searching or downloading. Moreover, the combination of MODIS products in both temporal and spatial terms was fast and effecting using the GEE API (Application Program Interface). All the products covering the globe and for the time period of 15 years were processed via a single collection. Most importantly, GEE allowed for including the calculation of SZAs covering the 24-hour day which improves the quality of the overall product. The 8-day global products of land surface albedo are available through http://www.rslab.gr/downloads.html

  17. Validation of spatially resolved all sky imager derived DNI nowcasts

    Science.gov (United States)

    Kuhn, Pascal; Wilbert, Stefan; Schüler, David; Prahl, Christoph; Haase, Thomas; Ramirez, Lourdes; Zarzalejo, Luis; Meyer, Angela; Vuilleumier, Laurent; Blanc, Philippe; Dubrana, Jean; Kazantzidis, Andreas; Schroedter-Homscheidt, Marion; Hirsch, Tobias; Pitz-Paal, Robert

    2017-06-01

    Mainly due to clouds, Direct Normal Irradiance (DNI) displays short-term local variabilities affecting the efficiency of concentrating solar power (CSP) plants. To enable efficient plant operation, DNI nowcasts in high spatial and temporal resolutions for 15 to 30 minutes ahead are required. Ground-based All Sky Imagers (ASI) can be used to detect, track and predict 3D positions of clouds possibly shading the plant. The accuracy and reliability of these ASI-derived DNI nowcasts must be known to allow its application in solar power plants. Within the framework of the European project DNICast, an ASI-based nowcasting system was developed and implemented at the Plataforma Solar de Almería (PSA). Its validation methodology and validation results are presented in this work. The nowcasting system outperforms persistence forecasts for volatile irradiance situations.

  18. The Evryscopes: monitoring the entire sky for exciting events

    Science.gov (United States)

    Law, Nicholas; Corbett, Hank; Howard, Ward S.; Fors, Octavi; Ratzloff, Jeff; Barlow, Brad; Hermes, JJ

    2018-01-01

    The Evryscope is a new type of array telescope which monitors the entire accessible sky in each exposure. The system, with 700 MPix covering an 8000-square-degree field of view, is building many-year-length, high-cadence light curves for every accessible object brighter than ∼16th magnitude. Every night, we add 600 million object detections to our databases, including exoplanet transits, microlensing events, nearby extragalactic transients, and a wide range of other short timescale events. I will present our science plans, the status of our current Evryscope systems (operational in Chile and soon California), the big-data analysis required to explore the petabyte-scale dataset we are collecting over the next few years, and the first results from the telescopes.

  19. On the COSMO-SkyMed Exploitation for Interferometric DEM Generation

    Science.gov (United States)

    Teresa, C. M.; Raffaele, N.; Oscar, N. D.; Fabio, B.

    2011-12-01

    DEM products for Earth observation space-borne applications are being to play a role of increasing importance due to the new generation of high resolution sensors (both optical and SAR). These new sensors demand elevation data for processing and, on the other hand, they provide new possibilities for DEM generation. Till now, for what concerns interferometric DEM, the Shuttle Radar Topography Mission (SRTM) has been the reference product for scientific applications all over the world. SRTM mission [1] had the challenging goal to meet the requirements for a homogeneous and reliable DEM fulfilling the DTED-2 specifications. However, new generation of high resolution sensors (including SAR) pose new requirements for elevation data in terms of vertical precision and spatial resolution. DEM are usually used as ancillary input in different processing steps as for instance geocoding and Differential SAR Interferometry. In this context, the recent SAR missions of DLR (TerraSAR-X and TanDEM-X) and ASI (COSMO-SkyMed) can play a promising role thanks to their high resolution both in space and time. In particular, the present work investigates the potentialities of the COSMO/SkyMed (CSK) constellation for ground elevation measurement with particular attention devoted to the impact of the improved spatial resolution wrt the previous SAR sensors. The recent scientific works, [2] and [3], have shown the advantages of using CSK in the monitoring of terrain deformations caused by landslides, earthquakes, etc. On the other hand, thanks to the high spatial resolution, CSK appears to be very promising in monitoring man-made structures, such as buildings, bridges, railways and highways, thus enabling new potential applications (urban applications, precise DEM, etc.). We present results obtained by processing both SPOTLIGHT and STRIPMAP acquisitions through standard SAR Interferometry as well as multi-pass interferometry [4] with the aim of measuring ground elevation. Acknowledgments

  20. Characteristics of Tropical Cyclones in High-Resolution Models of the Present Climate

    Science.gov (United States)

    Shaevitz, Daniel A.; Camargo, Suzana J.; Sobel, Adam H.; Jonas, Jeffery A.; Kim, Daeyhun; Kumar, Arun; LaRow, Timothy E.; Lim, Young-Kwon; Murakami, Hiroyuki; Roberts, Malcolm J.; hide

    2014-01-01

    The global characteristics of tropical cyclones (TCs) simulated by several climate models are analyzed and compared with observations. The global climate models were forced by the same sea surface temperature (SST) in two types of experiments, using a climatological SST and interannually varying SST. TC tracks and intensities are derived from each model's output fields by the group who ran that model, using their own preferred tracking scheme; the study considers the combination of model and tracking scheme as a single modeling system, and compares the properties derived from the different systems. Overall, the observed geographic distribution of global TC frequency was reasonably well reproduced. As expected, with the exception of one model, intensities of the simulated TC were lower than in observations, to a degree that varies considerably across models.

  1. Characteristics of Tropical Cyclones in High-resolution Models in the Present Climate

    Science.gov (United States)

    Shaevitz, Daniel A.; Camargo, Suzana J.; Sobel, Adam H.; Jonas, Jeffrey A.; Kim, Daehyun; Kumar, Arun; LaRow, Timothy E.; Lim, Young-Kwon; Murakami, Hiroyuki; Reed, Kevin; hide

    2014-01-01

    The global characteristics of tropical cyclones (TCs) simulated by several climate models are analyzed and compared with observations. The global climate models were forced by the same sea surface temperature (SST) fields in two types of experiments, using climatological SST and interannually varying SST. TC tracks and intensities are derived from each model's output fields by the group who ran that model, using their own preferred tracking scheme; the study considers the combination of model and tracking scheme as a single modeling system, and compares the properties derived from the different systems. Overall, the observed geographic distribution of global TC frequency was reasonably well reproduced. As expected, with the exception of one model, intensities of the simulated TC were lower than in observations, to a degree that varies considerably across models.

  2. AMSR2 all-sky radiance assimilation and its impact on the analysis and forecast of Hurricane Sandy with a limited-area data assimilation system

    Directory of Open Access Journals (Sweden)

    Chun Yang

    2016-06-01

    Full Text Available A method to assimilate all-sky radiances from the Advanced Microwave Scanning Radiometer 2 (AMSR2 was developed within the Weather Research and Forecasting (WRF model's data assimilation (WRFDA system. The four essential elements are: (1 extending the community radiative transform model's (CRTM interface to include hydrometeor profiles; (2 using total water Qt as the moisture control variable; (3 using a warm-rain physics scheme for partitioning the Qt increment into individual increments of water vapour, cloud liquid water and rain; and (4 adopting a symmetric observation error model for all-sky radiance assimilation.Compared to a benchmark experiment with no AMSR2 data, the impact of assimilating clear-sky or all-sky AMSR2 radiances on the analysis and forecast of Hurricane Sandy (2012 was assessed through analysis/forecast cycling experiments using WRF and WRFDA's three-dimensional variational (3DVAR data assimilation scheme. With more cloud/precipitation-affected data being assimilated around tropical cyclone (TC core areas in the all-sky AMSR2 assimilation experiment, better analyses were obtained in terms of the TC's central sea level pressure (CSLP, warm-core structure and cloud distribution. Substantial (>20 % error reduction in track and CSLP forecasts was achieved from both clear-sky and all-sky AMSR2 assimilation experiments, and this improvement was consistent from the analysis time to 72-h forecasts. Moreover, the all-sky assimilation experiment consistently yielded better track and CSLP forecasts than the clear-sky did for all forecast lead times, due to a better analysis in the TC core areas. Positive forecast impact from assimilating AMSR2 radiances is also seen when verified against the European Center for Medium-Range Weather Forecasts (ECMWF analysis and the Stage IV precipitation analysis, with an overall larger positive impact from the all-sky assimilation experiment.

  3. Dark Skies, Bright Kids: Year 2

    Science.gov (United States)

    Carlberg, Joleen K.; Johnson, K.; Lynch, R.; Walker, L.; Beaton, R.; Corby, J.; de Messieres, G.; Drosback, M.; Gugliucci, N.; Jackson, L.; Kingery, A.; Layman, S.; Murphy, E.; Richardson, W.; Ries, P.; Romero, C.; Sivakoff, G.; Sokal, K.; Trammell, G.; Whelan, D.; Yang, A.; Zasowski, G.

    2011-01-01

    The Dark Skies, Bright Kids (DSBK) outreach program brings astronomy education into local elementary schools in central Virginia's Southern Albemarle County through an after-school club. Taking advantage of the unusually dark night skies in the rural countryside, DSBK targets economically disadvantaged schools that tend to be underserved due to their rural locale. The goals of DSBK are to foster children's natural curiosity, demonstrate that science is a fun and creative process, challenge students' conceptions of what a scientist is and does, and teach some basic astronomy. Furthermore, DSBK works to assimilate families into students' education by holding family observing nights at the school. Now in its third semester, DSBK has successfully run programs at two schools with very diverse student populations. Working with these students has helped us to revise our activities and to create new ones. A by-product of our work has been the development of lesson plans, complete with learning goals and detailed instructions, that we make publically available on our website. This year we are expanding our repertoire with our new planetarium, which allows us to visualize topics in novel ways and supplements family observing on cloudy nights. The DSBK volunteers have also created a bilingual astronomy artbook --- designed, written, and illustrated by UVa students --- that we will publish and distribute to elementary schools in Virginia. Our book debuted at the last AAS winter meeting, and since then it has been extensively revised and updated with input from many individuals, including parents, professional educators, and a children's book author. Because the club is currently limited to serving a few elementary schools, this book will be part of our efforts to broaden our impact by bringing astronomy to schools we cannot go to ourselves and reaching out to Spanish-speaking communities at the same time.

  4. 76 FR 42704 - Sky River LLC; Notice of Filing

    Science.gov (United States)

    2011-07-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Sky River LLC; Notice of Filing Take notice that, on July 8, 2011, Sky River LLC filed to amend its Open Access Transmission Tariff (OATT) filing, submitted on April 1, 2011 and...

  5. Evaluation of the cloudy sky solar UVA radiation exposures.

    Science.gov (United States)

    Parisi, A V; Downs, N; Turner, J

    2014-09-05

    The influence of cloud on the solar UVA (320-400 nm) exposures over five minute periods on a horizontal plane has been investigated. The first approach used cloud modification factors that were evaluated using the influence of clouds on the global solar exposures (310-2800 nm) and a model developed to apply these to the clear sky UVA exposures to allow calculation of the five minute UVA exposures for any cloud conditions. The second approach established a relationship between the UVA and the global solar exposures. The models were developed using the first six months of data in 2012 for SZA less than or equal to 70° and were applied and evaluated for the exposures in the second half of 2012. This comparison of the modelled exposures for all cloud conditions to the measured data provided an R(2) of 0.8 for the cloud modification model, compared to an R(2) of 0.7 for the UVA/global model. The cloud modification model provided 73% of the five minute exposures within 20% of the measured UVA exposures. This was improved to 89% of the exposures within 20% of the measured UVA exposures for the cases of cloud with the sun not obscured. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Dark Skies Yuma: An NOAO and APS Program on Light Pollution Education

    Science.gov (United States)

    Pompea, Stephen M.; Walker, C. E.; Dugan, C.; Roddy, W. T.; Newhouse, M.

    2014-01-01

    Fifteen Yuma 6th grade teachers participated in a dark skies preservation and energy conservation professional development and classroom program delivered by NOAO during 2013. Two teacher professional development workshops and a culminating Family Science Night for students to display projects occurred. Between workshops, support was provided through real-time video conferencing using iPads. In the first workshop the teachers were provided foundational, scaffolded activities in accordance with STEM standards, resource materials in kits to facilitate the activities, and firsthand experiences in doing the activities with students. The second workshop focused on dark skies and energy education projects done in March and April. Teachers received training on how to work with classes on outdoor lighting in their communities and distinguish between energy efficient and wasteful outdoor lighting. In May, 2013, student projects were presented to parents and the school community as part of a Family Science Night and served as a form of authentic assessment of the students’ work. Participants will take away from this presentation new techniques for using iPads to sustain a community of educators as well as immersing them (and in turn, their students) in Project Based Learning after a scaffolded sequence of activities on dark skies preservation and energy conservation. View a video of the Family Science Night event at http://www.noao.edu/education/video/Dark-Skies-A-Night-of-Light/.

  7. The Past, Present and Future of Cyber-Physical Systems: A Focus on Models

    Directory of Open Access Journals (Sweden)

    Edward A. Lee

    2015-02-01

    Full Text Available This paper is about better engineering of cyber-physical systems (CPSs through better models. Deterministic models have historically proven extremely useful and arguably form the kingpin of the industrial revolution and the digital and information technology revolutions. Key deterministic models that have proven successful include differential equations, synchronous digital logic and single-threaded imperative programs. Cyber-physical systems, however, combine these models in such a way that determinism is not preserved. Two projects show that deterministic CPS models with faithful physical realizations are possible and practical. The first project is PRET, which shows that the timing precision of synchronous digital logic can be practically made available at the software level of abstraction. The second project is Ptides (programming temporally-integrated distributed embedded systems, which shows that deterministic models for distributed cyber-physical systems have practical faithful realizations. These projects are existence proofs that deterministic CPS models are possible and practical.

  8. Contributions of artificial lighting sources on light pollution in Hong Kong measured through a night sky brightness monitoring network

    Science.gov (United States)

    Pun, Chun Shing Jason; So, Chu Wing; Leung, Wai Yan; Wong, Chung Fai

    2014-05-01

    Light pollution is a form of environmental degradation in which excessive artificial outdoor lighting, such as street lamps, neon signs, and illuminated signboards, affects the natural environment and the ecosystem. Poorly designed outdoor lighting not only wastes energy, money, and valuable Earth resources, but also robs us of our beautiful night sky. Effects of light pollution on the night sky can be evaluated by the skyglow caused by these artificial lighting sources, through measurements of the night sky brightness (NSB). The Hong Kong Night Sky Brightness Monitoring Network (NSN) was established to monitor in detail the conditions of light pollution in Hong Kong. Monitoring stations were set up throughout the city covering a wide range of urban and rural settings to continuously measure the variations of the NSB. Over 4.6 million night sky measurements were collected from 18 distinct locations between May 2010 and March 2013. This huge dataset, over two thousand times larger than our previous survey [1], forms the backbone for studies of the temporal and geographical variations of this environmental parameter and its correlation with various natural and artificial factors. The concepts and methodology of the NSN were presented here, together with an analysis of the overall night sky conditions in Hong Kong. The average NSB in Hong Kong, excluding data affected by the Moon, was 16.8 mag arcsec-2, or 82 times brighter than the dark site standard established by the International Astronomical Union (IAU) [2]. The urban night sky was on average 15 times brighter than that in a rural location, firmly establishing the effects of artificial lighting sources on the night sky.

  9. The New Progress of the Starry Sky Project of China

    Science.gov (United States)

    Wang, Xiaohua

    2015-08-01

    Since the 28th General Assembly of IAU, the SSPC team made new progress:1. Enhanced the function of the SSPC team-- Established the contact with IAU C50, IUCN Dark Skies Advisory Group, AWB and IDA,and undertakes the work of the IDA Beijing Chapter.-- Got supports from China’s National Astronomical Observatories, Beijing Planetarium, and Shanghai Science and Technology Museum.-- Signed cooperation agreements with Lighting Research Center, English Education Group and law Firm; formed the team force.2. Put forward a proposal to national top institutionThe SSPC submitted the first proposal about dark sky protection to the Chinese People’s Political Consultative Conference.3. Introduced the Criteria and Guideline of dark sky protectionThe SSPC team translated 8 documents of IDA, and provided a reference basis for Chinese dark sky protection.4. Actively establish dark sky places-- Plan a Dark Sky Reserve around Ali astronomical observatory (5,100m elevation) in Tibet. China’s Xinhua News Agency released the news.-- Combining with Hangcuo Lake, a National Natural Reserve and Scenic in Tibet, to plan and establish the Dark Sky Park.-- Cooperated with Shandong Longgang Tourism Group to construct the Dream Sky Theme Park in the suburbs of Jinan city.In the IYL 2015, the SSPC is getting further development:First, make dark sky protection enter National Ecological Strategy of “Beautiful China”. We call on: “Beautiful China” needs “Beautiful Night Sky” China should care the shared starry sky, and left this resource and heritage for children.Second, hold “Cosmic Light” exhibition in Shanghai Science and Technology Museum on August.Third, continue to establish Dark Sky Reserve, Park and Theme Park. We want to make these places become the bases of dark sky protection, astronomical education and ecological tourism, and develop into new cultural industry.Fourth, actively join international cooperation.Now, “Blue Sky, White Cloud and Starry Sky “have become

  10. Disaggregation of Active/Passive Microwave Soil Moisture Under All-sky Condition Using Machine learning approach

    Science.gov (United States)

    Kim, Seongkyun; Kim, Hyunglok; Choi, Minha

    2017-04-01

    Remotely sensed soil moisture products measured from the active/passive microwave sensors on-board satellite platforms have a great impact on many hydro-meteorological analyses at a global scale. However, its coarse spatial resolution interrupts local scale soil moisture applications. Moreover, most downscaling methods using optical and thermal dataset, are applicable only in cloud-free conditions; thus developed downscaling method under all sky condition is essential for the construction of spatio-temporal continuity of datasets at fine resolution. In present study Support Vector Machine (SVM) regression model was utilized to downscale the satellite-based soil moisture retrievals. The 12.5 km spatial resolution of active microwave soil moisture datasets from the Advanced Scatterometer (ASCAT) and the 40 km resolution of passive microwave soil moisture datasets from the Soil Moisture Active Passive (SMAP) passive soil moisture were disaggregated to 1 km high resolution products over Northeast Asia in 2016. Optically derived estimates of surface temperature (LST), normalized difference vegetation index (NDVI), and its cloud products were obtained from MODerate Resolution Imaging Spectroradiometer (MODIS) for the purpose of downscaling soil moisture in finer resolution under all sky condition. Furthermore, a comparison analysis between in situ and downscaled soil moisture products was also conducted for quantitatively assessing its accuracy.

  11. Gaia, an all sky astrometric and photometric survey

    Science.gov (United States)

    Carrasco, J. M.

    2017-04-01

    Gaia space mission includes a low resolution spectroscopic instrument to classify and parametrize the observed sources. Gaia is a full-sky unbiased survey down to about 20th magnitude. The scanning law yields a rather uniform coverage of the sky over the full mission. The data reduction is a global one over the full mission. Both sky coverage and data reduction strategy ensure an unprecedented all-sky homogeneous spectrophotometric survey. Certainly, that survey is of interest for future on-ground and space projects (LSST, PLATO, EUCLID, ...). This work addresses the exploitation of the Gaia spectrophotometry as standard photometry reference through the discussion of the sky coverage, the spectrophotometric precision and the expected uncertainties of the synthetic photometry derived from the low resolution Gaia spectra and photometry.

  12. Stability of the nine sky quality meters in the Dutch night sky brightness monitoring network.

    Science.gov (United States)

    den Outer, Peter; Lolkema, Dorien; Haaima, Marty; van der Hoff, Rene; Spoelstra, Henk; Schmidt, Wim

    2015-04-22

    In the context of monitoring abundance of artificial light at night, the year-to-year stability of Sky Quality Meters (SQMs) is investigated by analysing intercalibrations derived from two measurement campaigns that were held in 2011 and 2012. An intercalibration comprises a light sensitivity factor and an offset for each SQM. The campaigns were concerned with monitoring measurements, each lasting one month. Nine SQMs, together forming the Night Sky Brightness Monitoring network (MHN) in The Netherlands, were involved in both campaigns. The stability of the intercalibration of these instruments leads to a year-to-year uncertainty (standard deviation) of 5% in the measured median luminance occurring at the MHN monitoring locations. For the 10-percentiles and 90-percentiles, we find 8% and 4%, respectively. This means that, for urban and industrial areas, changes in the sky brightness larger than 5% become detectable. Rural and nature areas require an 8%-9% change of the median luminance to be detectable. The light sensitivety agrees within 8% for the whole group of SQMs.

  13. Day/night whole sky imagers for 24-h cloud and sky assessment: history and overview.

    Science.gov (United States)

    Shields, Janet E; Karr, Monette E; Johnson, Richard W; Burden, Art R

    2013-03-10

    A family of fully automated digital whole sky imagers (WSIs) has been developed at the Marine Physical Laboratory over many years, for a variety of research and military applications. The most advanced of these, the day/night whole sky imagers (D/N WSIs), acquire digital imagery of the full sky down to the horizon under all conditions from full sunlight to starlight. Cloud algorithms process the imagery to automatically detect the locations of cloud for both day and night. The instruments can provide absolute radiance distribution over the full radiance range from starlight through daylight. The WSIs were fielded in 1984, followed by the D/N WSIs in 1992. These many years of experience and development have resulted in very capable instruments and algorithms that remain unique. This article discusses the history of the development of the D/N WSIs, system design, algorithms, and data products. The paper cites many reports with more detailed technical documentation. Further details of calibration, day and night algorithms, and cloud free line-of-sight results will be discussed in future articles.

  14. Rapid Prototyping — A Tool for Presenting 3-Dimensional Digital Models Produced by Terrestrial Laser Scanning

    Directory of Open Access Journals (Sweden)

    Juho-Pekka Virtanen

    2014-07-01

    Full Text Available Rapid prototyping has received considerable interest with the introduction of affordable rapid prototyping machines. These machines can be used to manufacture physical models from three-dimensional digital mesh models. In this paper, we compare the results obtained with a new, affordable, rapid prototyping machine, and a traditional professional machine. Two separate data sets are used for this, both of which were acquired using terrestrial laser scanning. Both of the machines were able to produce complex and highly detailed geometries in plastic material from models based on terrestrial laser scanning. The dimensional accuracies and detail levels of the machines were comparable, and the physical artifacts caused by the fused deposition modeling (FDM technique used in the rapid prototyping machines could be found in both models. The accuracy of terrestrial laser scanning exceeded the requirements for manufacturing physical models of large statues and building segments at a 1:40 scale.

  15. The Impact of Peer Observation and Feedback on Technical Seminar Presentations: A Constructive Model

    Science.gov (United States)

    Vani, V. Vijaya

    2015-01-01

    The present paper attempts to showcase the need and importance of peer observation and feedback in developing technical seminar presentation skills of the students at tertiary level. The paper endeavors to know whether a structured format will help students to know what they have to observe in the seminar presentations to give constructive…

  16. Hyperspectral imaging simulation of object under sea-sky background

    Science.gov (United States)

    Wang, Biao; Lin, Jia-xuan; Gao, Wei; Yue, Hui

    2016-10-01

    Remote sensing image simulation plays an important role in spaceborne/airborne load demonstration and algorithm development. Hyperspectral imaging is valuable in marine monitoring, search and rescue. On the demand of spectral imaging of objects under the complex sea scene, physics based simulation method of spectral image of object under sea scene is proposed. On the development of an imaging simulation model considering object, background, atmosphere conditions, sensor, it is able to examine the influence of wind speed, atmosphere conditions and other environment factors change on spectral image quality under complex sea scene. Firstly, the sea scattering model is established based on the Philips sea spectral model, the rough surface scattering theory and the water volume scattering characteristics. The measured bi directional reflectance distribution function (BRDF) data of objects is fit to the statistical model. MODTRAN software is used to obtain solar illumination on the sea, sky brightness, the atmosphere transmittance from sea to sensor and atmosphere backscattered radiance, and Monte Carlo ray tracing method is used to calculate the sea surface object composite scattering and spectral image. Finally, the object spectrum is acquired by the space transformation, radiation degradation and adding the noise. The model connects the spectrum image with the environmental parameters, the object parameters, and the sensor parameters, which provide a tool for the load demonstration and algorithm development.

  17. Lake Michigan lake trout PCB model forecast post audit (oral presentation)

    Science.gov (United States)

    Scenario forecasts for total PCBs in Lake Michigan (LM) lake trout were conducted using the linked LM2-Toxics and LM Food Chain models, supported by a suite of additional LM models. Efforts were conducted under the Lake Michigan Mass Balance Study and the post audit represents an...

  18. Presenting Thin Media Models Affects Women's Choice of Diet or Normal Snacks

    Science.gov (United States)

    Krahe, Barbara; Krause, Christina

    2010-01-01

    Our study explored the influence of thin- versus normal-size media models and of self-reported restrained eating behavior on women's observed snacking behavior. Fifty female undergraduates saw a set of advertisements for beauty products showing either thin or computer-altered normal-size female models, allegedly as part of a study on effective…

  19. Present-day 3D structural model of the Po Valley basin, Northern Italy

    NARCIS (Netherlands)

    Turrini, C.; Lacombe, O.; Roure, F.

    2014-01-01

    A 3D structural model of the Po Valley basin (Northern Italy) was built by integrating the dataset available from the public domain (DEM, wells, isobath-maps, cross-sections, outcrop-trends).The model shows the complex foredeep-foreland architecture across the basin, from the Moho level to the

  20. The effect of PLS regression in PLS path model estimation when multicollinearity is present

    DEFF Research Database (Denmark)

    Nielsen, Rikke; Kristensen, Kai; Eskildsen, Jacob

    PLS path modelling has previously been found to be robust to multicollinearity both between latent variables and between manifest variables of a common latent variable (see e.g. Cassel et al. (1999), Kristensen, Eskildsen (2005), Westlund et al. (2008)). However, most of the studies investigate...... models with relatively few variables and very simple dependence structures compared to the models that are often estimated in practical settings. A recent study by Nielsen et al. (2009) found that when model structure is more complex, PLS path modelling is not as robust to multicollinearity between...... latent variables as previously assumed. A difference in the standard error of path coefficients of as much as 83% was found between moderate and severe levels of multicollinearity. Large differences were found not only for large path coefficients, but also for small path coefficients and in some cases...

  1. The MOXE X-ray all-sky monitor for Spectrum-X-Gamma

    Energy Technology Data Exchange (ETDEWEB)

    In`t Zand, J.J.M.; Priedhorsky, W.C.; Moss, C.E. [and others

    1994-08-01

    MOXE is an X-ray all-sky monitor to be flown on the Russian Spectrum-X-Gamma satellite, to be launched in a few years. It will monitor several hundred X-ray sources on a daily basis, and will be the first instrument to monitor most of the X-ray sky most of the time. MOXE will alert users of more sensitive instruments on Russia`s giant high energy astrophysics observatory and of other instruments to transient activity. MOXE consists of an array of 6 X-ray pinhole cameras, sensitive from 3 to 25 keV, which views 4{pi} steradians (except for a 20{degree} {times} 80{degree} patch which includes the Sun). The pinhole apertures of 0.625 {times} 2.556 cm{sup 2} imply an angular resolution of 2{degree}.4 {times} 9{degree}.7 (on-axis). The MOXE hardware program includes an engineering model, now delivered, and a flight model. The flight instrument will mass approximately 118 kg and draw 38 Watts. For a non-focusing all-sky instrument that is limited by sky background, the limiting sensitivity is a function only of detector area. MOXE, with 6,000 cm{sup 2} of detector area, will, for a 24 hrs exposure, have a sensitivity of approximately 2 mCrab. MOXE distinguishes itself with respect to other all-sky monitors in its high duty cycle, thus being particularly sensitive to transient phenomena with time scales between minutes and hours.

  2. Promoting Dark Sky Protection in Chile: the Gabriel Mistral IDA Dark Sky Sanctuary and Other AURA Initiatives

    Science.gov (United States)

    Smith, R. Chris; Smith, Malcolm; Pompea, Stephen; Sanhueza, Pedro; AURA-Chile EPO Team

    2018-01-01

    For over 20 years, AURA has been leading efforts promoting the protection of dark skies in northern Chile. Efforts began in the early 1990s at AURA's Cerro Tololo Inter-American Observatory (CTIO), working in collaboration with other international observatories in Chile including Las Campanas Observatory (LCO) and the European Southern Observatory (ESO). CTIO also partnered with local communities, for example supporting Vicuña's effort to establish the first municipal observatory in Chile. Today we have developed a multifaceted effort of dark sky protection, including proactive government relations at national and local levels, a strong educational and public outreach program, and a program of highlighting international recognition of the dark skies through the IDA Dark Sky Places program. Work on international recognition has included the declaration of the Gabriel Mistral IDA Dark Sky Sanctuary, the first such IDA sanctuary in the world.

  3. The great canoes in the sky starlore and astronomy of the South Pacific

    CERN Document Server

    Chadwick, Stephen Robert

    2017-01-01

    Presenting spectacular photographs of astronomical objects of the southern sky, all taken by author Stephen Chadwick, this book explores what peoples of the South Pacific see when they look up at the heavens and what they have done with this knowledge. From wives killing brothers to emus rising out of the desert and great canoes in the sky, this book offers the perfect blend of science, tradition and mythology to bring to life the most famous sights in the heavens above the southern hemisphere. The authors place this starlore in the context of contemporary understandings of astronomy. The night sky of southern societies is as rich in culture as it is in stars. Stories, myths and legends based on constellations, heavenly bodies and other night sky phenomena have played a fundamental role in shaping the culture of pre-modern civilizations throughout the world. Such starlore continues to influence societies throughout the Pacific to this day, with cultures throughout the region – from Australia and New Zealand...

  4. Dark Skies Awareness Programs for the International Year of Astronomy: Involvement, Outcomes and Sustainability

    Science.gov (United States)

    Walker, Constance E.

    2010-01-01

    The preservation of dark skies is a growing global concern, yet it is one of the easiest environmental problems people can address on local levels. For this reason, the goal of the IYA Dark Skies Awareness Cornerstone Project is to raise public awareness of the impact of artificial lighting on local environments by getting people worldwide involved in a variety of programs. These programs provide resources on light pollution for new technologies like a presence in Second Life and podcasts, for local thematic events at national parks and observatory open houses, for international thematic events like International Dark Skies Week and Earth Hour, for a program in the arts like an international photo contest, for global citizen-science programs that measure night sky brightness worldwide, and for educational materials like a kit with a light shielding demonstration. These programs have been successfully used around the world during IYA to raise awareness of the effects of light pollution on public health, economic issues, ecological consequences, energy conservation, safety and security, and astronomy. The presentation will provide an update, take a look ahead at the project's sustainability, and describe how people can be involved in the future. Information about the programs is at www.darkskiesawareness.org.

  5. Treaty on Open Skies sensor technologies with potential international safeguards applications

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, M.B.

    1996-12-01

    The Treaty on Open Skies is a precedent-setting agreement that allows signatory states to fly aircraft over each other`s territory with sensor systems. The purpose of the Treaty is to improve confidence and security with respect to military activities of the signatories. This paper reviews the sensor technology that is currently allowed by the Treaty on Open Skies and potential future sensor technology. The Treaty on Open Skies does have provisions to allow for the improvement of the technology of the current sensor systems and for the proposal of new sensors after a period of time. This can occur only after the Treaty has been ratified and has entered into force. If this regime was to be used for other than Treaty on Open Skies applications some modifications to the allowed sensor technology should be examined. This paper presents some ideas on potential improvements to existing allowed sensor technology as well as some suggested new advanced sensor systems that would be useful for future potential monitoring of safeguard`s related activities. This paper addresses advanced imaging sensors and non-imaging sensors for potential use in aerial remote sensing roles that involve international data sharing.

  6. On the characteristic equation (Formula presented.) and its use in the context of a cell population model

    NARCIS (Netherlands)

    Diekmann, Odo; Getto, Philipp; Nakata, Yukihiko

    2016-01-01

    In this paper we characterize the stability boundary in the (Formula presented.) -plane, for fixed (Formula presented.) with (Formula presented.) , for the characteristic equation from the title. Subsequently we describe a nonlinear cell population model involving quiescence and show that this

  7. Introducing WISDEM:An Integrated System Modeling for Wind Turbines and Plant (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Dykes, K.; Graf, P.; Scott, G.; Ning, A.; King, R.; Guo, Y.; Parsons, T.; Damiani, R.; Felker, F.; Veers, P.

    2015-01-01

    The National Wind Technology Center wind energy systems engineering initiative has developed an analysis platform to leverage its research capabilities toward integrating wind energy engineering and cost models across wind plants. This Wind-Plant Integrated System Design & Engineering Model (WISDEM) platform captures the important interactions between various subsystems to achieve a better National Wind Technology Center wind energy systems engineering initiative has developed an analysis platform to leverage its research capabilities toward integrating wind energy engineering and cost models across wind plants. This Wind-Plant Integrated System Design & Engineering Model (WISDEM) platform captures the important interactions between various subsystems to achieve a better understanding of how to improve system-level performance and achieve system-level cost reductions. This work illustrates a few case studies with WISDEM that focus on the design and analysis of wind turbines and plants at different system levels.

  8. Environmental Models as a Service: Enabling Interoperability through RESTful Endpoints and API Documentation (presentation)

    Science.gov (United States)

    Achieving interoperability in environmental modeling has evolved as software technology has progressed. The recent rise of cloud computing and proliferation of web services initiated a new stage for creating interoperable systems. Scientific programmers increasingly take advantag...

  9. Developing Charismatic Delivery through Transformational Presentations: Modeling the Persona of Steve Jobs

    Science.gov (United States)

    Ivic, Rebecca K.; Green, Robert J.

    2012-01-01

    How can public speaking instructors teach students how to be charismatic and confident speakers? The activity presented in this article suggests that instructors foster competent and charismatic presentational skills by having students channel the stylistic capabilities of an exceptional speaker. The activity requires students to take on the…

  10. Global Clear-Sky Surface Skin Temperature from Multiple Satellites Using a Single-Channel Algorithm with Angular Anisotropy Corrections

    Science.gov (United States)

    Scarino, Benjamin R.; Minnis, Patrick; Chee, Thad; Bedka, Kristopher M.; Yost, Christopher R.; Palikonda, Rabindra

    2017-01-01

    Surface skin temperature (T(sub s)) is an important parameter for characterizing the energy exchange at the ground/water-atmosphere interface. The Satellite ClOud and Radiation Property retrieval System (SatCORPS) employs a single-channel thermal-infrared (TIR) method to retrieve T(sub s) over clear-sky land and ocean surfaces from data taken by geostationary Earth orbit (GEO) and low Earth orbit (LEO) satellite imagers. GEO satellites can provide somewhat continuous estimates of T(sub s) over the diurnal cycle in non-polar regions, while polar T(sub s) retrievals from LEO imagers, such as the Advanced Very High Resolution Radiometer (AVHRR), can complement the GEO measurements. The combined global coverage of remotely sensed T(sub s), along with accompanying cloud and surface radiation parameters, produced in near-realtime and from historical satellite data, should be beneficial for both weather and climate applications. For example, near-realtime hourly T(sub s) observations can be assimilated in high-temporal-resolution numerical weather prediction models and historical observations can be used for validation or assimilation of climate models. Key drawbacks to the utility of TIR-derived T(sub s) data include the limitation to clear-sky conditions, the reliance on a particular set of analyses/reanalyses necessary for atmospheric corrections, and the dependence on viewing and illumination angles. Therefore, T(sub s) validation with established references is essential, as is proper evaluation of T(sub s) sensitivity to atmospheric correction source. This article presents improvements on the NASA Langley GEO satellite and AVHRR TIR-based T(sub s) product that is derived using a single-channel technique. The resulting clear-sky skin temperature values are validated with surface references and independent satellite products. Furthermore, an empirically adjusted theoretical model of satellite land surface temperature (LST) angular anisotropy is tested to improve

  11. Sky luminance distribution in Pamplona (Spain) during the summer period

    Science.gov (United States)

    Torres, J. L.; de Blas, M.; García, A.; Gracia, A.; de Francisco, A.

    2010-04-01

    In this work the outdoor daylight conditions in Pamplona (South Europe) during the summer period have been studied. The selected sky type (from fifteen standards) at a given moment is the one exhibiting the lowest RMSD when comparing the theoretical and experimental luminance distributions in the sky hemisphere. Two year data of luminance distribution registered every 10 min in 145 positions of the sky hemisphere have been used for selecting the sky type. The most frequent sky type in Pamplona is V.5 (cloudless polluted with a broad solar corona), with an occurrence of 29.5%. This result coincides with the one observed in a previous study in Athens. Six types of sky (V.5, IV.4, III.4, III.3, V.4 y II.2) out of the fifteen standards become practically the 80% of all the studied ones. Regarding a possible use in daylight climate studies, the frequency of occurrence of the fifteen types of sky for fourteen solar elevation intervals has been included.

  12. Review of past and present research on experimental models of moyamoya disease

    Directory of Open Access Journals (Sweden)

    Shuji Hamauchi

    2015-01-01

    Full Text Available Moyamoya disease (MMD is characterized by a progressive steno-occlusive disease affecting the terminal portions of the cerebral internal carotid artery (ICA and by formation of an abnormal vascular network at the base of the brain. Several pathogeneses, including inflammation, immune complex, upregulation of angiogenic factors, and abnormality of endothelial progenitor cells (EPCs have been hypothesized. However, the mechanisms of MMD are largely unknown, and in vivo and in vitro models of MMD have not yet been established. Previously, inflammation- and immune-complex-related animal models have been reported but failed to reproduce severe stenotic lesions in the terminal portion of ICA. Thereafter, several clinical studies revealed that angiogenic activity of circulating EPCs was defective in MMD patients. These results suggested that the function and quantity of EPCs could be useful as a cellular model of MMD. Very recently, RING finger protein 213 (RNF213 was identified as an MMD susceptibility gene, a discovery that led to the efforts to generate gene mutation-based animal models. Although RNF213 knockout animal models have not yet successfully represented the phenotype of MMD, they have provided new insights into the role of RNF213 in remodeling after vascular injury and postischemic angiogenesis. Furthermore, the use of induced pluripotent stem cells (iPSCs and an appropriate differentiation protocol have made it possible to obtain abundant quantities of MMD-specific vascular cells. In summary, studies have shown that endothelial cells derived from MMD-iPSCs have impaired angiogenic activity, which is a finding consistent with the results of EPC studies. Further studies are needed to create true MMD-specific experimental models to promote understanding of MMC pathogenesis and aid drug development.

  13. Pesticides in groundwater: modelling and data analysis of the past, present and future

    DEFF Research Database (Denmark)

    Binning, Philip John; McKnight, Ursula S.; Malaguerra, Flavio

    to jointly manage our groundwater and surface water resources. Here, observed pesticide data is analyzed and combined with models to address these questions and needs. Groundwater and surface water pesticide observations reflect the fact that these two hydrological components have a strong interaction....... For example, many older and banned pesticides are detected in streams and reflect the groundwater baseflow contribution to stream flow. Models of groundwater age and pesticide transport demonstrate the importance of geology and pumping regime in determining observed groundwater concentrations. Finally...

  14. Cataloging the Entire Sky with NOAO

    Science.gov (United States)

    Nidever, David; Dey, Arjun; Olsen, Knut; Nikutta, Robert; Juneau, Stephanie; NOAO Data Lab Team

    2018-01-01

    More than two thirds of the sky has now been imaged in at least one band with NOAO's telescopes. The large majority of these data were obtained for PI-led projects and surveys, and thus far only a small fraction have been released to the community via well-calibrated and easily accessible catalogs. We are remedying this by creating a catalog of sources from most of the public data taken using the CTIO-4m+DECam and KPNO-4m+Mosaic3. This catalog, called the NOAO Source Catalog (NSC), currently covers ~25,000 square degrees, contains 20 billion individual measurements of 2 billion unique objects, and has 10-sigma depths of ~23rd magnitude in most broad-band filters and astrometric accuracy of ~20 mas. The NSC can be used to investigate stellar streams, dwarf satellite galaxies, galaxy distributions, variable stars and other transients. I will give an overview of the first public data release distributed through NOAO Data Lab and discuss initial results from a search for Milky Way satellite galaxies using the new catalog.

  15. Asymmetric sky from the long mode modulations

    Science.gov (United States)

    Abolhasani, Ali Akbar; Baghram, Shant; Firouzjahi, Hassan; Namjoo, Mohammad Hossein

    2014-03-01

    The observed hemispherical power asymmetry in cosmic microwave background radiation may have originated from the modulations of superhorizon long-wavelength modes. In this work, we unveil different aspects of asymmetries generated from the long-wavelength mode modulations. We show that the same mechanism that leads to the observed cosmic microwave background hemispherical power asymmetry via superhorizon long-mode perturbation also yields dipole asymmetry in (a) the tensor perturbations power spectrum and (b) the halo bias parameter. These are different phenomena relevant to different cosmological histories, but both share the same underlying mechanism in generating asymmetries in the sky. We obtain the set of consistency conditions relating the amplitude of dipole asymmetries generated on tensor perturbations and halo bias parameter to the amplitude of dipole asymmetry generated on cosmic microwave background power spectrum. In addition, we show that this mechanism does not produce dipole asymmetry in acceleration expansion in an ΛCDM Universe because the superhorizon curvature perturbation is conserved in this background.

  16. Vanilla Sky – El cuento del narcisista

    Directory of Open Access Journals (Sweden)

    Graham St. John STOTT

    2016-09-01

    Full Text Available Vanilla Sky (2001, de Cameron Crowe, normalmente se aprecia como un juego intelectual; no obstante, su temática es mucho más oscura que lo que dicha etiqueta podría sugerir. Mientras recorre las diferentes fases del sueño de David Aames (un sueño en el que se mueve de una pretensión de amor a una de homicidio, nos damos cuenta de que David padece un trastorno de la autoestima. Utilizando como referencia Atracción Fatal (1987, de Adrian Lyne, para demostrar la incapacidad de tener en cuenta las necesidades de otros, la película de Crowe nos muestra un caso práctico de trastorno narcisista de la personalidad. David mata porque no es capaz de aceptar las exigencias de otros, ya que supondría para él ponerse en una condición inferior a la autosuficiencia. No resulta sorprendente, por lo tanto, su horror cuando al final de la película se despierta y descubre que su amante sigue viva.

  17. Dark Skies, Bright Kids Year 6

    Science.gov (United States)

    Liss, Sandra; Troup, Nicholas William; Johnson, Kelsey E.; Barcos-Munoz, Loreto D.; Beaton, Rachael; Bittle, Lauren; Borish, Henry J.; Burkhardt, Andrew; Corby, Joanna; Dean, Janice; Hancock, Danielle; King, Jennie; Prager, Brian; Romero, Charles; Sokal, Kimberly R.; Stierwalt, Sabrina; Wenger, Trey; Zucker, Catherine

    2015-01-01

    Now entering our sixth year of operation, Dark Skies, Bright Kids (DSBK) is an entirely volunteer-run outreach organization based out of the Department of Astronomy at the University of Virginia. Our core mission is to enhance elementary science education and literacy in central Virginia through fun, hands-on activities that introduce basic Astronomy concepts beyond Virginia's Standards of Learning. Our primary focus is hosting an 8-10 week after-school astronomy club at underserved elementary and middle schools. Each week, DSBK volunteers take the role of coaches to introduce astronomy-related concepts ranging from the Solar System to galaxies to astrobiology, and to lead students in interactive learning activities. Another hallmark of DSBK is hosting our Annual Central Virginia Star Party, a free event open to the community featuring star-gazing and planetarium shows.DSBK has amassed over 15,000 contact hours since 2009 and we continue to broaden our impact. One important step we have taken in the past year is to establish a graduate student led assessment program to identify and implement directed learning goals for DSBK outreach. The collection of student workbooks, observations, and volunteer surveys indicates broad scale success for the program both in terms of student learning and their perception of science. The data also reveal opportunities to improve our organizational and educational practices to maximize student achievement and overall volunteer satisfaction for DSBK's future clubs and outreach endeavors.

  18. Blue Sky Birds Come to the World

    Directory of Open Access Journals (Sweden)

    Bura Sabiha Kelek

    2015-06-01

    Full Text Available The New Supply System comes to all fields for logistics.Drone is an unmanned vehicle for loading and unloading packages.Perhaps we can imagine it as a ‘’blue sky bird’’. This new trend has three important impacts that are determined by technoligical capabilities, ,regularity pressure, and public acceptance so that it will be dealed within current powers and circumstances. This kind of vehicles are used in different capacities, such as multicopter,drone or robot.Logistics’ issues are interested in short-term delivery systems for customer satisfaction but all developments go through GPS so it is based on 21st century technological developments, which have been tested on a short-term basis and will be expected to be of use in 2 years. The purpose of this research is to give lead to researchers information about risk and the advantages of using the technology in this manner.Some advantages and disadvantages ,schedules’ problems in the system will be identifed.

  19. WFIRST: Simulating the Wide-Field Sky

    Science.gov (United States)

    Peeples, Molly; WFIRST Wide Field Imager Simulations Working Group

    2018-01-01

    As astronomy’s first high-resolution wide-field multi-mode instrument, simulated data will play a vital role in the planning for and analysis of data from WFIRST’s WFI (Wide Field Imager) instrument. Part of the key to WFIRST’s scientific success lies in our ability to push the systematics limit, but in order to do so, the WFI pipeline will need to be able to measure and take out said systematics. The efficacy of this pipeline can only be verified with large suites of synthetic data; these data must include both the range of astrophysical sky scenes (from crowded starfields to high-latitude grism data observations) and the systematics from the detector and telescope optics the WFI pipeline aims to mitigate. We summarize here(1) the status of current and planned astrophysical simulations in support of the WFI,(2) the status of current WFI instrument simulators and requirements on future generations thereof, and(3) plans, methods, and requirements on interfacing astrophysical simulations and WFI instrument simulators.

  20. Lighting up the sky for CERN's anniversary

    CERN Multimedia

    2004-01-01

    For CERN's Golden Jubilee, the Canton of Geneva, supported by the Pays de Gex local authorities, lit up eight points around the LHC ring. On the date of CERN's fiftieth anniversary, 29 September 2004, the Organization's Host State authorities gave the Laboratory a gift of light. As night fell, twenty-four powerful floodlights blazed into the night sky from the eight access points to the future LHC. For the many spectators gathered at a special vantage point above the village of Crozet, these beams emanating from the valley floor marked out the locations of the access shafts around the 27-km of the LHC tunnel.The event was organised by the Department of Justice, Police and Security of the Canton of Geneva, with the participation of the Crozet local council and support of local councils in the Canton of Geneva, the Communauté des communes of the Pays de Gex, and the Ain Préfecture. This joint gift from the local authorities on both sides of the French-Swiss border has great symbolic value for an organisatio...

  1. CALCLENS: weak lensing simulations for large-area sky surveys and second-order effects in cosmic shear power spectra

    Science.gov (United States)

    Becker, Matthew R.

    2013-10-01

    I present a new algorithm, Curved-sky grAvitational Lensing for Cosmological Light conE simulatioNS (CALCLENS), for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This new algorithm properly accounts for the sky curvature and boundary conditions, is able to produce redshift-dependent shear signals including corrections to the Born approximation by using multiple-plane ray tracing and properly computes the lensed images of source galaxies in the light cone. The key feature of this algorithm is a new, computationally efficient Poisson solver for the sphere that combines spherical harmonic transform and multigrid methods. As a result, large areas of sky (˜10 000 square degrees) can be ray traced efficiently at high resolution using only a few hundred cores. Using this new algorithm and curved-sky calculations that only use a slower but more accurate spherical harmonic transform Poisson solver, I study the convergence, shear E-mode, shear B-mode and rotation mode power spectra. Employing full-sky E/B-mode decompositions, I confirm that the numerically computed shear B-mode and rotation mode power spectra are equal at high accuracy (≲1 per cent) as expected from perturbation theory up to second order. Coupled with realistic galaxy populations placed in large N-body light cone simulations, this new algorithm is ideally suited for the construction of synthetic weak lensing shear catalogues to be used to test for systematic effects in data analysis procedures for upcoming large-area sky surveys. The implementation presented in this work, written in C and employing widely available software libraries to maintain portability, is publicly available at http://code.google.com/p/calclens.

  2. A rigorous treatment of a follow-the-leader traffic model with traffic lights present

    Energy Technology Data Exchange (ETDEWEB)

    Argall, Brenna; Cheleshkin, Eugene; Greenberg, J.M.; Hinde, Colin; Lin, Pei-Jen

    2003-07-16

    Traffic flow on a unidirectional roadway in the presence of traffic lights is modeled. Individual car responses to green, yellow, and red lights are postulated and these result in rules governing the acceleration and deceleration of individual cars. The essence of the model is that only specific cars are directly affected by the lights. The other cars behave according to simple follow-the-leader rules which limit their speed by the spacing between it and the car directly ahead. The model has a number of desirable properties; namely cars do not run red lights, cars do not smash into one another, and cars exhibit no velocity reversals. In a situation with multiple lights operating in-phase we get, after an initial startup period, a constant number of cars through each light during any green-yellow period. Moreover, this flux is less by one or two cars per period than the flux obtained in discretized versions of the idealized Lighthill, Whitham, Richards model which allows for infinite accelerations.

  3. First-order fire effects on herbs and Shrubs: present knowledge and process modeling needs

    Science.gov (United States)

    Kirsten Stephan; Melanie Miller; Matthew B. Dickinson

    2010-01-01

    Herbaceous plants and shrubs have received little attention in terms of fire effects modeling despite their critical role in ecosystem integrity and resilience after wildfires and prescribed burns. In this paper, we summarize current knowledge of direct effects of fire on herb and shrub (including cacti) vegetative tissues and seed banks, propose key components for...

  4. Promoter or enhancer, what's the difference? Deconstruction of established distinctions and presentation of a unifying model

    DEFF Research Database (Denmark)

    Andersson, Robin

    2015-01-01

    Gene transcription is strictly controlled by the interplay of regulatory events at gene promoters and gene-distal regulatory elements called enhancers. Despite extensive studies of enhancers, we still have a very limited understanding of their mechanisms of action and their restricted spatio...... a unifying model of regulatory elements in transcriptional regulation, in which activity, transcriptional output and regulatory function is context specific....

  5. Modelling past, present and future peatland carbon accumulation across the pan-Arctic region

    Directory of Open Access Journals (Sweden)

    N. Chaudhary

    2017-09-01

    Full Text Available Most northern peatlands developed during the Holocene, sequestering large amounts of carbon in terrestrial ecosystems. However, recent syntheses have highlighted the gaps in our understanding of peatland carbon accumulation. Assessments of the long-term carbon accumulation rate and possible warming-driven changes in these accumulation rates can therefore benefit from process-based modelling studies. We employed an individual-based dynamic global ecosystem model with dynamic peatland and permafrost functionalities and patch-based vegetation dynamics to quantify long-term carbon accumulation rates and to assess the effects of historical and projected climate change on peatland carbon balances across the pan-Arctic region. Our results are broadly consistent with published regional and global carbon accumulation estimates. A majority of modelled peatland sites in Scandinavia, Europe, Russia and central and eastern Canada change from carbon sinks through the Holocene to potential carbon sources in the coming century. In contrast, the carbon sink capacity of modelled sites in Siberia, far eastern Russia, Alaska and western and northern Canada was predicted to increase in the coming century. The greatest changes were evident in eastern Siberia, north-western Canada and in Alaska, where peat production hampered by permafrost and low productivity due the cold climate in these regions in the past was simulated to increase greatly due to warming, a wetter climate and higher CO2 levels by the year 2100. In contrast, our model predicts that sites that are expected to experience reduced precipitation rates and are currently permafrost free will lose more carbon in the future.

  6. Modelling past, present and future peatland carbon accumulation across the pan-Arctic region

    Science.gov (United States)

    Chaudhary, Nitin; Miller, Paul A.; Smith, Benjamin

    2017-09-01

    Most northern peatlands developed during the Holocene, sequestering large amounts of carbon in terrestrial ecosystems. However, recent syntheses have highlighted the gaps in our understanding of peatland carbon accumulation. Assessments of the long-term carbon accumulation rate and possible warming-driven changes in these accumulation rates can therefore benefit from process-based modelling studies. We employed an individual-based dynamic global ecosystem model with dynamic peatland and permafrost functionalities and patch-based vegetation dynamics to quantify long-term carbon accumulation rates and to assess the effects of historical and projected climate change on peatland carbon balances across the pan-Arctic region. Our results are broadly consistent with published regional and global carbon accumulation estimates. A majority of modelled peatland sites in Scandinavia, Europe, Russia and central and eastern Canada change from carbon sinks through the Holocene to potential carbon sources in the coming century. In contrast, the carbon sink capacity of modelled sites in Siberia, far eastern Russia, Alaska and western and northern Canada was predicted to increase in the coming century. The greatest changes were evident in eastern Siberia, north-western Canada and in Alaska, where peat production hampered by permafrost and low productivity due the cold climate in these regions in the past was simulated to increase greatly due to warming, a wetter climate and higher CO2 levels by the year 2100. In contrast, our model predicts that sites that are expected to experience reduced precipitation rates and are currently permafrost free will lose more carbon in the future.

  7. Near-infrared sky background fluctuations at mid- and low latitudes

    Science.gov (United States)

    Moreels, G.; Clairemidi, J.; Faivre, M.; Pautet, D.; Rubio da Costa, F.; Rousselot, P.; Meriwether, J. W.; Lehmacher, G. A.; Vidal, E.; Chau, J. L.; Monnet, G.

    2008-10-01

    The emission of the upper atmosphere introduces an additional variable component into observations of astronomical objects in the NIR 700 3,000 nm range. The subtraction of this component is not easy because it varies during the night by as much as 100% and it is not homogeneous over the sky. A program aimed at measuring and understanding the main characteristics of the atmospheric NIR emission was undertaken. A 512 × 512 CCD camera equipped with a RG780/2 mm filter is used to obtain images of the sky in a 36° × 36° field of view. The intensities of a given star and of the nearby region devoid of star in a 439 arcmin2 area are monitored during periods of time of several hours. The sky intensity measured in the 754 900 nm bandpass, reduced to zenith and zero airmass is comprised between mag20 and mag18.5 per arcsecond2. A diminution by a factor of two during the night is frequently observed. Intensity fluctuations having an amplitude of 15% and periods of 5 40 min are present in the images with a structure of regularly spaced stripes. The fluctuations of the NIR sky background intensity are due to (1) the chemical evolution of the upper atmosphere composition during the night and (2) dynamical processes such as tides with periods of 3 6 h or gravity waves with periods of several tens of minutes. We suggest that a monitoring of the sky background intensity could be set up when quantitative observations of astronomical objects require exposure times longer than ~10 min. The publication is illustrated with several video films accessible on the web site http://www.obs-besancon.fr/nirsky/ fr/nirsky/" TargetType="URL"/> . Enter username: nirsky and password: skynir.

  8. Body wave travel times and amplitudes for present-day seismic model of Mars

    Science.gov (United States)

    Raevskiy, Sergey; Gudkova, Tamara

    At the moment Martian interior structure models are constrained by the satellite observational data (the mass, the moment of inertia factor, the Love number k _{2}) (Konopliv et al., 2011) and high pressure experimental data (Bertka and Fei, 1997). Seismological observations could provide unparalleled capability for studying Martian interiors. Future missions include seismic experiments on Mars (Lognonné et al., 2012). The main instrument for these seismic experiments is a broadband seismometer (Robert et al., 2012). When seismic measurements are not yet available, physically consistent interior models, characterized by properties of relevant minerals, make possible to study of the seismic response of the planet. \\To estimate travel times for direct P, S, core reflected PcP, ScS and core refracted PKP body waves as a function of epicentral distance and hypocentral depth, as well as their amplitudes at the surface for a given marsquake, software product was developed in MatLab, as it encompasses many plotting routines that plot resulting travel times and ray paths. The computational results have been compared with the program TTBox (Knapmeyer, 2004). The code computes seismic ray paths and travel times for a one-dimentional spherical interior model (density and seismic velocities are functions of a radius only). Calculations of travel times tables for direct P, S, core reflected PcP, ScS and core refracted PKP waves and their amplitudes are carried out for a trial seismic model of Mars M14_3 from (Zharkov et al., 2009): the core radius is 1800 km, the thickness of the crust is 50 km. Direct and core reflected P and S waves are recorded to a maximum epicentral distance equal to about 100(°) , and PKP arrivals can be detected for epicental distances larger than 150(°) . The shadow zone is getting wider in comparison with previous results (Knapmeyer, 2010), as the liquid core radius of the seismic model under consideration is larger. Based on the estimates of

  9. Getting Students to Observe the Night Sky, Even When Your Sky is Cloudy Half the Time

    Science.gov (United States)

    Shipman, Harry L.

    2010-01-01

    Teachers of introductory astronomy classes often wish to get our students to look at the night sky However, most educational institutions in America are located in regions where cloudy nights are relatively common. This paper describes a low cost way to integrate observations into a course which lacks a dedicated astronomy lab. Students in two large. general science classes in fall 2008 and spring 2009 were asked to participate in one of two global star-counting projects. The fall project was coordinated by UCAR and asked for observations of the constellation Cygnus (http://www.windows.ucar.edu/citizen_science/starcount/results.html). The spring project was run by Project Globe and asked for observations of the constellation Orion. (http://www.globe.gov/GaN/ ). In both cases, students simply find the constellation, match the star pattern to charts that go to different limiting magnitudes, and report the data to the coordinating organization. A copy of the report is sent to the course instructor. The instructor can ask for additional information. Did it work? The success of this project was evaluated by analyzing the e-mail messages that students returned in response to the assignment. In both courses, a very large majority of the students actually did the exercise and submitted a report. Students reported that observing the sky in this way was satisfying to them., and sometimes the reports were quite enthusiastic. In spring 2009, some preparatory activies were conducted during class that were designed to sensitize students to the beauty of the sky. Analysis of student reports indicated that these preparatory activities were helpful, but not as helpful as the instructor would like. This research is part of the Teacher Professional Continuum project at the University of Delaware, which is supported by the National Science Foundation.

  10. Recommendations on presenting LHC searches for missing transverse energy signals using simplified s-channel models of dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Boveia, Antonio [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Antwerp Univ., Wilrijk (Belgium); Buchmueller, Oliver [Imperial College, London (United Kingdom); Busoni, Giorgio [Univ. of Melbourne (Australia); D' Eramo, Francesco [Univ. of California, Santa Cruz, CA (United States); De Roeck, Albert [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Antwerp Univ., Wilrijk (Belgium); De Simone, Andrea [Istituto Nazionale di Fisica Nucleare (INFN), Trieste (Italy); Doglioni, Caterina [Lund Univ. (Sweden); Dolan, Matthew J. [Univ. of Melbourne (Australia); Genest, Marie-Helene [Univ. of Grenoble, Saint-Martin-d' Hares (France); Hahn, Kristian [Northwestern Univ., Evanston, IL (United States); Haisch, Ulrich [Univ. of Oxford (United Kingdom); European Organization for Nuclear Research (CERN), Geneva (Switzerland); Harris, Philip C. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Heisig, Jan [RWTH Aachen Univ. (Germany); Ippolito, Valerio [Harvard Univ., Cambridge, MA (United States); Kahlhoefer, Felix [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Khoze, Velentin V. [Durham Univ. (United Kingdom); Kulkarni, Sichota [Austrian Academy of Sciences, Wien (Austria); Landsberg, Greg [Brown Univ., Providence, RI (United States); Lowette, Steven [Vrije Univ., Amsterdam (Netherlands); Malik, Sarah [Imperial College, London (United Kingdom); Mangano, Michelangelo [European Organization for Nuclear Research (CERN), Geneva (Switzerland); McCabe, Christopher [Univ. of Amsterdam (Netherlands); Mrenna, Stephen [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Pani, Priscilla [Stockholm Univ. (Sweden); du Pree, Tristan [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Riotto, Antonio [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Salek, David [Univ. of Amsterdam (Netherlands); Nikhef, Amsterdam (Netherlands); Schmidt-Hoberg, Kai [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Shepherd, William [Univ. of Copenhagen (Denmark); Tait, Tim M.P. [Univ. of California, Irvine, CA (United States); Wang, Lian-Tao [Univ. of Chicago, IL (United States); Worm, Steven [Science and Technology Facilities Council (STFC), Oxford (United Kingdom). Rutherford Appleton Lab. (RAL); Zurek, Kathryn [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-03-14

    This document summarises the proposal of the LHC Dark Matter Working Group on how to present LHC results on s-channel simplified dark matter models and to compare them to direct (indirect) detection experiments.

  11. Recommendations on presenting LHC searches for missing transverse energy signals using simplified $s$-channel models of dark matter

    CERN Document Server

    Boveia, Antonio; Busoni, Giorgio; D'Eramo, Francesco; De Roeck, Albert; De Simone, Andrea; Doglioni, Caterina; Dolan, Matthew J.; Genest, Marie-Helene; Hahn, Kristian; Haisch, Ulrich; Harris, Philip C.; Heisig, Jan; Ippolito, Valerio; Kahlhoefer, Felix; Khoze, Valentin V.; Kulkarni, Suchita; Landsberg, Greg; Lowette, Steven; Malik, Sarah; Mangano, Michelangelo; McCabe, Christopher; Mrenna, Stephen; Pani, Priscilla; Pree, Tristan du; Riotto, Antonio; Salek, David; Schmidt-Hoberg, Kai; Shepherd, William; Tait, Tim M. P.; Wang, Lian-Tao; Worm, Steven; Zurek, Kathryn

    2016-01-01

    This document summarises the proposal of the LHC Dark Matter Working Group on how to present LHC results on $s$-channel simplified dark matter models and to compare them to direct (indirect) detection experiments.

  12. Using Model-Based System Engineering to Provide Artifacts for NASA Project Life-Cycle and Technical Reviews Presentation

    Science.gov (United States)

    Parrott, Edith L.; Weiland, Karen J.

    2017-01-01

    This is the presentation for the AIAA Space conference in September 2017. It highlights key information from Using Model-Based Systems Engineering to Provide Artifacts for NASA Project Life-cycle and Technical Reviews paper.

  13. Absolute parameters of eclipsing binaries in Southern Hemisphere sky - II: QY Tel

    Science.gov (United States)

    Erdem, A.; Sürgit, D.; Engelbrecht, C. A.; van Heerden, H. P.; Manick, R.

    2016-11-01

    This paper presents the first analysis of spectroscopic and photometric observations of the neglected southern eclipsing binary star, QY Tel. Spectroscopic observations were carried out at the South African Astronomical Observatory in 2013. New radial velocity curves from this study and V light curves from the All Sky Automated Survey were solved simultaneously using modern light and radial velocity curve synthesis methods. The final model describes QY Tel as a detached binary star where both component stars fill at least half of their Roche limiting lobes. The masses and radii were found to be 1.32 (± 0.06) M⊙, 1.74 (± 0.15) R⊙ and 1.44 (± 0.09) M⊙, 2.70 (± 0.16) R⊙ for the primary and secondary components of the system, respectively. The distance to QY Tel was calculated as 365 (± 40) pc, taking into account interstellar extinction. The evolution case of QY Tel is also examined. Both components of the system are evolved main-sequence stars with an age of approximately 3.2 Gy, when compared to Geneva theoretical evolution models.

  14. Absolute parameters of detached binaries in the southern sky - III: HO Tel

    Science.gov (United States)

    Sürgit, D.; Erdem, A.; Engelbrecht, C. A.; van Heerden, H. P.; Manick, R.

    2017-07-01

    We present the first radial velocity analysis of the southern eclipsing binary star HO Tel, based on spectra obtained at the South African Astronomical Observatory in 2013. The orbital solution of this neglected binary gave the quite large spectroscopic mass ratio of 0.921(±0.005). The V light curve from the All Sky Automated Survey (ASAS) and Walraven five-colour (WULBV) photometric light curves (Spoelstra and Van Houten 1972) were solved simultaneously using the Wilson-Devinney code supplemented by the Monte Carlo search method. The final photometric model describes HO Tel as a detached binary star where both component stars fill about three-quarters of their Roche limiting lobes. The masses and radii were found to be 1.88(±0.04) M⊙, 2.28(±0.15) R⊙ and 1.73(±0.04) M⊙, 2.08(±0.16) R⊙ for the primary and secondary components of the system, respectively. The distance to HO Tel was calculated as 282(±30) pc, taking into account interstellar extinction. The evolution case of HO Tel was also examined. Both components of the system are evolved main-sequence stars with an age of approximately 1.1 Gy, when compared to Geneva theoretical evolution models.

  15. The present and future of the most favoured inflationary models after Planck 2015

    Energy Technology Data Exchange (ETDEWEB)

    Escudero, Miguel; Ramírez, Héctor; Boubekeur, Lotfi; Mena, Olga [Instituto de Física Corpuscular (IFIC), CSIC-Universitat de Valencia, Apartado de Correos 22085, E-46071 (Spain); Giusarma, Elena, E-mail: miguel.escudero@ific.uv.es, E-mail: hector.ramirez@ific.uv.es, E-mail: lboubekeur@usfq.edu.ec, E-mail: elena.giusarma@roma1.infn.it, E-mail: olga.mena@ific.uv.es [Physics Department and INFN, Università di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185, Rome (Italy)

    2016-02-01

    The value of the tensor-to-scalar ratio r in the region allowed by the latest Planck 2015 measurements can be associated to a large variety of inflationary models. We discuss here the potential of future Cosmic Microwave Background cosmological observations in disentangling among the possible theoretical scenarios allowed by our analyses of current Planck temperature and polarization data. Rather than focusing only on r, we focus as well on the running of the primordial power spectrum, α{sub s} and the running thereof, β{sub s}. If future cosmological measurements, as those from the COrE mission, confirm the current best-fit value for β{sub s} ∼> 10{sup −2} as the preferred one, it will be possible to rule-out the most favoured inflationary models.

  16. Modelling the many-body dynamics of heavy ion collisions. Present status and future perspective

    Energy Technology Data Exchange (ETDEWEB)

    Hartnack, Ch.; Puri, R.K.; Aichelin, J. [Centre National de la Recherche Scientifique, 44 - Nantes (France). Lab. de Physique Subatomique et des Technologies Associees; Konopka, J.; Bass, S.A.; Stoecker, H.; Greiner, W. [Johann Wolfgang Goethe Univ., Frankfurt am Main (Germany). Inst. fuer Theoretische Physik

    1996-12-31

    Basic problems of the semiclassical microscopic modelling of strongly interacting systems are discussed within the framework of Quantum Molecular Dynamics (QMD). It is shown that the same predictions can be obtained with several - numerically completely different and independently written -programs as far as the same model parameters are employed and the same basic approximations are made. Some of the physical results, however, depend also on rather technical parameters like the preparation of the initial configuration in phase space. This crucial problem is connected with the description of the ground state of single nuclei, which differs among the various approaches. An outlook to an improved molecular dynamics scheme for heavy ion collisions is given. (author). 86 refs.

  17. The chlorine budget of the present-day atmosphere - A modeling study

    Science.gov (United States)

    Weisenstein, Debra K.; Ko, Malcolm K. W.; Sze, Nien-Dak

    1992-01-01

    The contribution of source gases to the total amount of inorganic chlorine (ClY) is examined analytically with a time-dependent model employing 11 source gases. The source-gas emission data are described, and the modeling methodology is set forth with attention given to the data interpretation. The abundances and distributions are obtained for all 11 source gases with corresponding ClY production rates and mixing ratios. It is shown that the ClY production rate and the ClY mixing ratio for each source gas are spatially dependent, and the change in the relative contributions from 1950 to 1990 is given. Ozone changes in the past decade are characterized by losses in the polar and midlatitude lower stratosphere. The values for CFC-11, CCl4, and CH3CCl3 suggest that they are more evident in the lower stratosphere than is suggested by steady-state estimates based on surface concentrations.

  18. Present capabilities and new developments in antenna modeling with the numerical electromagnetics code NEC

    Energy Technology Data Exchange (ETDEWEB)

    Burke, G.J.

    1988-04-08

    Computer modeling of antennas, since its start in the late 1960's, has become a powerful and widely used tool for antenna design. Computer codes have been developed based on the Method-of-Moments, Geometrical Theory of Diffraction, or integration of Maxwell's equations. Of such tools, the Numerical Electromagnetics Code-Method of Moments (NEC) has become one of the most widely used codes for modeling resonant sized antennas. There are several reasons for this including the systematic updating and extension of its capabilities, extensive user-oriented documentation and accessibility of its developers for user assistance. The result is that there are estimated to be several hundred users of various versions of NEC world wide. 23 refs., 10 figs.

  19. The present-day climate of Greenland : a study with a regional climate model

    NARCIS (Netherlands)

    Ettema, J.

    2010-01-01

    Present-day climate of Greenland Over the past 20 years, the Greenland ice sheet (GrIS) has warmed. This temperature increase can be explained by an increase in downwelling longwave radiation due to a warmer overlying atmosphere. These temperature changes are strongly correlated to changes in the

  20. An interactive boundary layer modeling methodology for aerodynamic flows[Presentation

    CSIR Research Space (South Africa)

    Smith, L

    2011-11-01

    Full Text Available -1 Proceedings of the ASME 2011 International Mechanical Engineering Congress & Exposition IMECE2011 November 11-17, 2011, Denver, Colorado, USA AN INTERACTIVE BOUNDARY LAYER MODELING METHODOLOGY FOR AERODYNAMIC FLOWS Lelanie Smith, University of Pretoria..., Pretoria, Gauteng, South Africa Josua P Meyer, University of Pretoria, Pretoria, Gauteng, South Africa Oliver F Oxtoby, Council for Scientific and Industrial Research, Pretoria, Gauteng, South Africa Arnuad G Malan, Council for Scientific and Industrial...

  1. FDTD based model of ISOCT imaging for validation of nanoscale sensitivity (Conference Presentation)

    Science.gov (United States)

    Eid, Aya; Zhang, Di; Yi, Ji; Backman, Vadim

    2017-02-01

    Many of the earliest structural changes associated with neoplasia occur on the micro and nanometer scale, and thus appear histologically normal. Our group has established Inverse Spectroscopic OCT (ISOCT), a spectral based technique to extract nanoscale sensitive metrics derived from the OCT signal. Thus, there is a need to model light transport through relatively large volumes (< 50 um^3) of media with nanoscale level resolution. Finite Difference Time Domain (FDTD) is an iterative approach which directly solves Maxwell's equations to robustly estimate the electric and magnetic fields propagating through a sample. The sample's refractive index for every spatial voxel and wavelength are specified upon a grid with voxel sizes on the order of λ/20, making it an ideal modelling technique for nanoscale structure analysis. Here, we utilize the FDTD technique to validate the nanoscale sensing ability of ISOCT. The use of FDTD for OCT modelling requires three components: calculating the source beam as it propagates through the optical system, computing the sample's scattered field using FDTD, and finally propagating the scattered field back through the optical system. The principles of Fourier optics are employed to focus this interference field through a 4f optical system and onto the detector. Three-dimensional numerical samples are generated from a given refractive index correlation function with known parameters, and subsequent OCT images and mass density correlation function metrics are computed. We show that while the resolvability of the OCT image remains diffraction limited, spectral analysis allows nanoscale sensitive metrics to be extracted.

  2. Optical metabolic imaging measures early drug response in an allograft murine breast cancer model (Conference Presentation)

    Science.gov (United States)

    Sharick, Joe T.; Cook, Rebecca S.; Skala, Melissa C.

    2017-02-01

    Previous work has shown that cellular-level Optical Metabolic Imaging (OMI) of organoids derived from human breast cancer cell-line xenografts accurately and rapidly predicts in vivo response to therapy. To validate OMI as a predictive measure of treatment response in an immune-competent model, we used the polyomavirus middle-T (PyVmT) transgenic mouse breast cancer model. The PyVmT model includes intra-tumoral heterogeneity and a complex tumor microenvironment that can influence treatment responses. Three-dimensional organoids generated from primary PyVmT tumor tissue were treated with a chemotherapy (paclitaxel) and a PI3K inhibitor (XL147), each alone or in combination. Cellular subpopulations of response were measured using the OMI Index, a composite endpoint of metabolic response comprised of the optical redox ratio (ratio of the fluorescence intensities of metabolic co-enzymes NAD(P)H to FAD) as well as the fluorescence lifetimes of NAD(P)H and FAD. Combination treatment significantly decreased the OMI Index of PyVmT tumor organoids (padaptive immunity. Thus, this method is promising for use in humans to predict long-term treatment responses accurately and rapidly, and could aid in clinical treatment planning.

  3. Recommendations on presenting LHC searches for missing transverse energy signals using simplified s-channel models of dark matter

    DEFF Research Database (Denmark)

    Boveia, Antonio; Buchmueller, Oliver; Busoni, Giorgio

    2016-01-01

    This document summarises the proposal of the LHC Dark Matter Working Group on how to present LHC results on $s$-channel simplified dark matter models and to compare them to direct (indirect) detection experiments.......This document summarises the proposal of the LHC Dark Matter Working Group on how to present LHC results on $s$-channel simplified dark matter models and to compare them to direct (indirect) detection experiments....

  4. Measuring the color and brightness of artificial sky glow from cities using an all-sky imaging system calibrated with astronomical methods in the Johnson-Cousins B and V photometric systems

    Science.gov (United States)

    Pipkin, Ashley; Duriscoe, Dan M.; Lughinbuhl, Christian

    2017-01-01

    Artificial light at night, when observed at some distance from a city, results in a dome of sky glow, brightest at the horizon. The spectral power distribution of electric light utilized will determine its color of the light dome and the amount of light will determine its brightness. Recent outdoor lighting technologies have included blue-rich light emitting diode (LED) sources that may increase the relative amount of blue to green light in sky glow compared to typical high pressure sodium (HPS) sources with warmer spectra. Measuring and monitoring this effect is important to the preservation of night sky visual quality as seen from undeveloped areas outside the city, such as parks or other protected areas, since the dark-adapted human eye is more sensitive to blue and green. We present a method using a wide field CCD camera which images the entire sky in both Johnson V and B photometric bands. Standard stars within the images are used for calibration. The resulting all-sky brightness maps, and a derived B-V color index map, provide a means to assess and track the impact of specific outdoor lighting practices. We also present example data from several cities, including Las Vegas, Nevada, Flagstaff, Arizona, and Cheyenne, Wyoming.

  5. Supporting research and technology activities in the preparation of a three-dimensional map of the infrared sky

    Science.gov (United States)

    Tarter, Jill C.

    1993-01-01

    The final report for the period 15 Mar. 1986 to 31 Mar. 1993 for the Cooperative Agreement is presented. The purpose of this Cooperative Agreement was to collaborate with NASA civil servant and contractor personnel, and other Institute personnel in a project to use all available cataloged astronomical infrared data to construct a detailed three dimensional model of the infrared sky. Areas of research included: IRAS colors of normal stars and the infrared excesses in Be stars; galactic structure; how to use the observed IRAS source counts as a function of position to deduce the physical structure of the galaxy; IRAS properties of metal-poor stars; IRAS database studies; and solar space exploration including projects such as the Space Station Gas-Grain Simulator and the Mars Rover/Sample Return Mission.

  6. The cultural route of present and lost landscapes in the centre of Bucharest - digital model

    Science.gov (United States)

    Bostenaru-Dan, Maria

    2015-04-01

    We are developing a digital model of the Magheru boulevard in central Bucharest. This N-S axis in the centre of the city is a unique encounter with interwar architecture. It is a protected area in the city, with buildings listed individually or as group of monuments, and also with protection at urban planning level. But at the same time the landscape does not facilitate the building of urban routes between monuments. A GIS model of the area exists, but does not yet take into account this heritage value of the buildings, being developed in a civil engineering environment. It is also one of the few partial 3D models of Bucharest. It allows datascapes of various buidling characteristics. At the same time a 3D model which equally covers all items in an area is ressources expensive. Hence, we propose, similarly to strategic planning to do a Kevin Lynch type selection. Landmarks will be identified as nodes of the routes, and the remaining area treated as zone. Ways connect the nodes and we paid special attention as we will see to their landscape. We developed a concept on how to further build from the idea of layers in GIS to include the issue of scale. As such, floor plans can build strategic points for the nodes of the route such as in Nolli or Sitte plans. Cooperation between GIS and GoogleEarth is envisaged, since GoogleEarth allows for detailing in SketchUp for the interior space. This way we developed an alternative digital model to the levels of detail of CityGML, the classical for 3D city models. The route itself is to be analysed with the method of Space Syntax. While this part of the research focused on the built heritage, on culture, we included also issues of landscape. First, the landscape of the boulevard has to be shaped as to build the route between these nodes of the route. Our concept includes the creation of pocket parks and of links between the pocket parks through vegetal and mineral elements to connect them. Existing urban spaces and empty plots are

  7. Paper and Slides on Draft Nonroad Emission Inventory Model: Presented at 12th International Emission Inventory Conference, April 2003

    Science.gov (United States)

    Description of the most current draft of the NONROAD model and how it version differs from prior versions. Nationwide model outputs are presented and compared for HC, CO, NOx, PM, SOx (SO2), and fuel consumption, for diesel and for sparkignition engines.

  8. Treatment effect of balloon kyphoplasty and Sky expander kyphoplasty on vertebral compression fracture: a Meta-analysis

    Directory of Open Access Journals (Sweden)

    Wei HE

    2013-04-01

    Full Text Available Objective  To evaluate the treatment effect of balloon kyphoplasty (Pkp and Sky expander kyphoplasty (Sky on vertebral compression fracture, and provide a theoretical basis for clinical application. Methods  The database of Ovid medline, PubMed, Web of science, EMbase and CNKI from Jan. 1995 to Oct. 2012 were retrieved with computer, and relevant journals were manually retrieved, for the collection of the literature of therapeutic studies on treatment of vertebral compression fracture with Pkp and Sky method. The literature collected was then selected according to the inclusion and exclusion criteria, and analyzed by Meta-analysis software RevMan 5.0.25. Results  A total of 4 papers were selected based on that criterion, including 146 cases of Pkp group and 83 cases of Sky group. Random effect model analysis showed no significant difference existed between the two groups regarding postoperative anterior height and column height of vertebral body, Cobb angle and pain relieve (SMD=0.50, 95%CI -0.27–1.27; SMD=0.33, 95%CI -0.11–0.77; SMD=0.46, 95%CI -0.74–1.66; SMD=-0.09, 95%CI -0.37–0.18. However, the subgroup analysis showed the effect of Sky was better than that of Pkp on restoring anterior height and column height of vertebral body and Cobb angle. Conclusion  No significant difference was found regarding the treatment effect between Pkp and Sky method in the treatment of osteoporotic vertebral compression fracture, but the clinical effect of Sky was better because of fewer complications and lower medical cost.

  9. Models of presentation of intraarticular masses; Normas de presentacion de las masas intraarticulares

    Energy Technology Data Exchange (ETDEWEB)

    Vega, M. [Hospital Universitario Dr. Peset. Valencia (Spain); Molla, E. [Clinica Quiron. Valencia (Spain); Marti-Bonmati, L.; Galant, J. [Hospital San Juan. Alicante (Spain); Madariaga, B. [Hospital Clinico Zaragoza (Spain)

    2002-07-01

    Intraarticular masses are relatively rare, and their magnetic resonance (MR) features are little known. The purpose of this report was to asses the presentation and MR imaging findings associated with the different histological types encountered in a series of 22 patients. We review the MR imaging findings in 22 intraarticular masses (18 in knee, two in ankle and two in shoulder). The variables studied were: calcifications, edema, morphology, methemoglobin, hemosiderin, homogeneity, margins, bone changes, T1-weighted signal intensity, T2-weightes/STIR signal intensity, clinical presentation and patient age. The statistical relationships were determined by {chi}''2 test and ANOVA (Student-Newman-Keuls). Among the intraarticular masses, there were 14 cases of pigmented villonodular synovitis (SVNP) (63.6%), 3 cases of themangioma (13.6%), 3 cases of synovial sarcoma (13.6%) and 2 cases of chondrosarcoma (9.1%). Statistical significant relationships were observed between histological type and; calcifications (p=0.004), which were irregular in chondrosarcomas and appeared as phleboliths in hemangionas: morphology (p=0.007), which was serpiginous in hemangiomas and oval in focal SVNP; areas of hemosiderin (p=0.002)in SVNP and synovial sarcoma: clinica presentation (p=0.003), with skin changes in cases of hemangioma: and age (p=0.04), hemangioma patients being younger (mean: 21 years) and those with synovial sarcoma being older (mean: 56 years). In cases of intraarticular masses, the presence of calcification, tumor morphology, the presence of hemosiderin, patient age and clinical presentation show statistically significant differences depending on the histological type. (Author) 23 refs.

  10. Presentation, calibration and validation of the low-order, DCESS Earth System Model (Version 1

    Directory of Open Access Journals (Sweden)

    J. O. Pepke Pedersen

    2008-11-01

    Full Text Available A new, low-order Earth System Model is described, calibrated and tested against Earth system data. The model features modules for the atmosphere, ocean, ocean sediment, land biosphere and lithosphere and has been designed to simulate global change on time scales of years to millions of years. The atmosphere module considers radiation balance, meridional transport of heat and water vapor between low-mid latitude and high latitude zones, heat and gas exchange with the ocean and sea ice and snow cover. Gases considered are carbon dioxide and methane for all three carbon isotopes, nitrous oxide and oxygen. The ocean module has 100 m vertical resolution, carbonate chemistry and prescribed circulation and mixing. Ocean biogeochemical tracers are phosphate, dissolved oxygen, dissolved inorganic carbon for all three carbon isotopes and alkalinity. Biogenic production of particulate organic matter in the ocean surface layer depends on phosphate availability but with lower efficiency in the high latitude zone, as determined by model fit to ocean data. The calcite to organic carbon rain ratio depends on surface layer temperature. The semi-analytical, ocean sediment module considers calcium carbonate dissolution and oxic and anoxic organic matter remineralisation. The sediment is composed of calcite, non-calcite mineral and reactive organic matter. Sediment porosity profiles are related to sediment composition and a bioturbated layer of 0.1 m thickness is assumed. A sediment segment is ascribed to each ocean layer and segment area stems from observed ocean depth distributions. Sediment burial is calculated from sedimentation velocities at the base of the bioturbated layer. Bioturbation rates and oxic and anoxic remineralisation rates depend on organic carbon rain rates and dissolved oxygen concentrations. The land biosphere module considers leaves, wood, litter and soil. Net primary production depends on atmospheric carbon dioxide concentration and

  11. Modelling past landslide-induced tsunami in Lake Geneva to evaluate the present threat

    Science.gov (United States)

    Franz, Martin; Jaboyedoff, Michel; Podladchikov, Yury

    2014-05-01

    In the south-eastern part of Lake Geneva, in the community of Meillerie, France, is located a forested depression, which indicates that a landslide occurred at this place in a distant past. It is a partially submerged slide composed of Trias to Jurassic carbonates. As its volume is greater than 10 mio m3, we assume that a potential brusque failure would have generated an impulse wave able to spread across the lake and reach the location of contemporary cities. Since this type of events is still likely to occur nowadays, this study aims to characterise the tsunami triggered by the past landslide event in order to know the potential wave height in populated places around the lake for events of similar magnitude. The volume of the displaced mass is estimated using the inverse Sloping Local Base Level (SLBL) by subtracting the pre-failure topography (built with the SLBL) to the actual one. In order to model landslide-triggered tsunami, it is necessary to be able to simulate the generation, the propagation of the wave in the lake and on the shores. This task is performed using a two-dimensional numerical model based on the shallow water equations. The Lax-Friedrichs scheme is used for the numerical stabilisation. The preliminary results indicate that the wave propagated across the lake up to distant places. As the shores are today extensively urbanised, in a similar case, they would be subject to catastrophic consequences. Thus, sensitivity tests are conducted for variation of the size and the velocities of the landslide in the model in order to give a distribution of the associated risks.

  12. Building trusted national identity management systems: Presenting the privacy concern-trust (PCT) model

    DEFF Research Database (Denmark)

    Adjei, Joseph K.; Olesen, Henning

    This paper discusses the effect of trust and information privacy concerns on citizens’ attitude towards national identity management systems. We introduce the privacyconcerns- trust model, which shows the role of trust in mediating and moderating citizens’ attitude towards identity management...... systems. We adopted a qualitative research approach in our analysis of data that was gathered through a series of interviews and a stakeholder workshop in Ghana. Our findings indicate that, beyond the threshold level of trust, societal information privacy concern is low; hence, trust is high, thereby...... encouraging further institutional collaboration and acceptance of citizens’ informational self-determination....

  13. Modelling Groundwater Depletion at Regional and Global Scales: Present State and Future Prospects.

    Science.gov (United States)

    Wada, Yoshihide

    2015-01-01

    Except for frozen water in ice and glaciers, groundwater is the world's largest distributed store of freshwater and has strategic importance to global food and water security. In this paper, the most recent advances quantifying groundwater depletion (GWD) are comprehensively reviewed. This paper critically evaluates the recently advanced modeling approaches estimating GWD at regional and global scales, and the evidence of feedbacks to the Earth system including sea-level rise associated with GWD. Finally, critical challenges and opportunities in the use of groundwater are identified for the adaption to growing food demand and uncertain climate.

  14. Tropospheric haze and colors of the clear twilight sky.

    Science.gov (United States)

    Lee, Raymond L; Mollner, Duncan C

    2017-07-01

    At the earth's surface, clear-sky colors during civil twilights depend on the combined spectral effects of molecular scattering, extinction by tropospheric aerosols, and absorption by ozone. Molecular scattering alone cannot produce the most vivid twilight colors near the solar horizon, for which aerosol scattering and absorption are also required. However, less well known are haze aerosols' effects on twilight sky colors at larger scattering angles, including near the antisolar horizon. To analyze this range of colors, we compare 3D Monte Carlo simulations of skylight spectra with hyperspectral measurements of clear twilight skies over a wide range of aerosol optical depths. Our combined measurements and simulations indicate that (a) the purest antisolar twilight colors would occur in a purely molecular, multiple-scattering atmosphere, whereas (b) the most vivid solar-sky colors require at least some turbidity. Taken together, these results suggest that multiple scattering plays an important role in determining the redness of the antitwilight arch.

  15. Using All Sky Imaging to Improve Telescope Scheduling

    Science.gov (United States)

    Cole, Gary M.

    2017-06-01

    Automated scheduling makes it possible for a small telescope to observe a large number of targets in a single night. But when used in areas which have less-than-perfect sky conditions such automation can lead to large numbers of observations of clouds and haze. This paper describes the development of a "sky-aware" telescope automation system that integrates the data flow from an SBIG AllSky340c camera with an enhanced dispatch scheduler to make optimum use of the available observing conditions for two highly instrumented backyard telescopes. Using the minute by minute time series image stream and a self maintained reference database, the software maintains a file of sky brightness, transparency, stability, and forecasted visibility at several hundred grid positions. The scheduling software uses this information in real time to exclude targets obscured by clouds and select the best observing task, taking into account the requirements and limits of each instrument.

  16. Cloud Detection and Prediction with All Sky Cameras

    Directory of Open Access Journals (Sweden)

    Adam Jan

    2017-01-01

    This article gives a short overview about a method that uses an all sky camera with a 180 ° field of view to identify the cloud distribution by measuring the absorption of star light. It can be used to assign a sky quality rating to single spots, arbitrary regions or the whole sky at once within a 1 min exposure time. A cloud map can be created from the available data that can be used to determine shape and dimension of clouds and to predict their movement. The resulting data can be used by a scheduling algorithm or the operating crew to point the telescope to a different source before the current source gets covered by clouds. The all sky cameras used so far are located on La Palma at the observatory Roque de los Muchachos close to the telescopes FACT and MAGIC and the planned northern CTA site.

  17. Rapid approach to the quantitative determination of nocturnal ground irradiance in populated territories: a clear-sky case

    Science.gov (United States)

    Kocifaj, Miroslav; Petržala, Jaromír

    2016-11-01

    A zero-order approach to the solving of the radiative transfer equation and a method for obtaining the horizontal diffuse irradiance at night-time are both developed and intended for wide use in numerical predictions of nocturnal ground irradiance in populated territories. Downward diffuse radiative fluxes are computed with a two-stream approximation, and the data products obtained are useful for scientists who require rapid estimations of illumination levels during the night. The rapid technique presented here is especially important when the entire set of calculations is to be repeated for different lighting technologies and/or radiant intensity distributions with the aim of identifying high-level illuminance/irradiance, the spectral composition of scattered light or other optical properties of diffuse light at the ground level. The model allows for the computation of diffuse horizontal irradiance due to light emissions from ground-based sources with arbitrary spectral compositions. The optical response of a night sky is investigated using the ratio of downward to upward irradiance, R⊥, λ(0). We show that R⊥, λ(0) generally peaks at short wavelengths, thus suggesting that, e.g., the blue light of an LED lamp would make the sky even more bluish. However, this effect can be largely suppressed or even removed with the spectral sensitivity function of the average human eye superimposed on to the lamp spectrum. Basically, blue light scattering dominates at short optical distances, while red light is transmitted for longer distances and illuminates distant places. Computations are performed for unshielded as well as fully shielded lights, while the spectral function R⊥, λ(0) is tabulated to make possible the modelling of various artificial lights, including those not presented here.

  18. Measuring Overcast Colors with All-Sky Imaging

    Science.gov (United States)

    2008-04-01

    rather than diffusely reflected skylight spectra. To do so, I use a Photo Research PR-650 spectrora- diometer that has a spectral range of 380–780nm... Colorimetry of Overcasts from All-Sky Photographs Overcast skies yield an embarrassment of remote- sensing riches: cloud optical depths τ, radiances, and...chromaticity gamuts and turnings observed in real overcasts. Fig. 16. Scattering geometry for an object of radiance L0 seen by an observer through a multiple

  19. The Digital Sky Project: Database Technologies and Techniques

    Science.gov (United States)

    Brunner, Robert J.

    1998-05-01

    We will discuss the novel database technologies and techniques under development within the Digital Sky project which are required to seamlessly integrate and mine large datasets. The astronomical field is entering a new era as multiple, large area, digital sky surveys are coming on-line. These new datasets are not only interesting in their own right, but a truly revolutionary leap forward arises in the aggregation of complimentary, multi-wavelength surveys (i.e. the cross-identification of billions of sources). Federating these large, complex datasets, however, is not an easy task and represents a serious technical challenge. It is the solution to this challenge, as well as the development of the technology necessary to effectively mine the aggregate data, which is the goal of the Digital Sky project. These technologies include both hardware, to optimize the retrieval and analysis of geographically distributed datasets, and software, to simplify the ingestion of archives into the digital sky federation. For the former, we are utilizing our NPACI (National Partnership for Advanced Computational Infrastructure) relationship to identify new techniques for parallelizing both the retrieval and computational requirements, as well as innovative approaches, such as network weather, to improve the response between the distributed system components. In order to grow and develop, the digital sky will need to incorporate new surveys and datasets in addition to its original tenants: the 2MASS (2 Micron All Sky Survey) and DPOSS (Digitized Palomar Observatory Sky Survey) projects. This requirement necessitates a standardized, modular interface for each archive that allows for an exchange of both the types of data and the types of services provided by the constituent archives. This interface is built on a common sky partitioning scheme: the Hierarchical Triangulated Mesh, and a standardized metadata for astronomical surveys.

  20. Worldwide Impact: International Year of Astronomy Dark Skies Awareness Programs

    Science.gov (United States)

    Walker, C. E.; Pompea, S. M.; Isbell, D.

    2009-12-01

    The arc of the Milky Way seen from a truly dark location is part of our planet's natural heritage. More than one fifth of the world population, two thirds of the United States population and one half of the European Union population have already lost naked eye visibility of the Milky Way. This loss, caused by light pollution, is a serious and growing issue that impacts astronomical research, the economy, ecology, energy conservation, human health, public safety and our shared ability to see the night sky. For this reason, “Dark Skies Awareness” is a global cornerstone project of the International Year of Astronomy. Its goal is to raise public awareness of the impact of artificial lighting on local environments by getting people worldwide involved in a variety of programs through: - New Technology (website, podcasts, social networking, Second Life) - Educational Materials (Great Switch Out, a traveling exhibit, brochures, posters, CDs, DVDs, educational kit) - The Arts (photo contest) - Events (Earth Hour, International Dark Sky Week, World Night in Defense of Starlight, Dark Skies Discovery Sites, Sidewalk Astronomy, Nights in the Parks) - Citizen Science Programs (5 star hunting programs & Quiet Skies) Dark Skies Communities (Starlight Initiative, International Dark Sky Communities) Many countries around the world have participated in these programs. We will highlight 24 countries in particular and focus on successful techniques used in aspects of the programs, results and impact on the audience, and plans and challenges for maintaining or extending the program beyond the International Year of Astronomy. The International Year of Astronomy 2009 is partially funded from a grant from the National Science Foundation (NSF) Astronomy Division. The National Optical Astronomy Observatory is host to the IYA2009 Dark Skies Awareness programs and is operated by the Association of Universities for Research in Astronomy, Inc. under cooperative agreement with NSF.