Nouvelles approches en theorie du champ moyen dynamique: le cas du pouvoir thermoelectrique et celui de l'effet orbital d'un champ magnetique

NASA Astrophysics Data System (ADS)

Arsenault, Louis-Francois

Les applications reliees a la generation d'energie motivent la recherche de materiaux ayant un fort pouvoir thermoelectrique (S). De plus, S nous renseigne sur certaines proprietes fondamentales des materiaux, comme, par exemple, la transition entre l'etat coherent et incoherent des quasi-particules lorsque la temperature augmente. Empiriquement, la presence de fortes interactions electron-electron peut mener a un pouvoir thermoelectrique geant. Nous avons donc etudie le modele le plus simple qui tient compte de ces fortes interactions, le modele de Hubbard. La theorie du champ moyen dynamique (DMFT) est tout indiquee dans ce cas. Nous nous sommes concentres sur un systeme tridimensionnel (3d) cubique a face centree (fcc), et ce, pour plusieurs raisons. A) Ce type de cristal est tres commun dans la nature. B) La DMFT donne de tres bons resultats en 3d et donc ce choix sert aussi de preuve de principe de la methode. C) Finalement, a cause de la frustration electronique intrinseque au fcc, celui-ci ne presente pas de symetrie particule-trou, ce qui est tres favorable a l'apparition d'une grande valeur de S. Ce travail demontre que lorsque le materiau est un isolant a demi-remplissage a cause des fortes interactions (isolant de Mott), il est possible d'obtenir de grands pouvoirs thermoelectriques en le dopant legerement. C'est un resultat pratique important. Du point de vue methodologique, nous avons montre comment la limite de frequence infinie de S et l'approche dite de Kelvin, qui considere la limite de frequence nulle avant la limite thermodynamique pour S, donnent des estimations fiables de la vraie limite continue (DC) dans les domaines de temperature appropriee. Ces deux approches facilitent grandement les calculs en court-circuit ant la necessite de recourir a de problematiques prolongements analytiques. Nous avons trouve que la methode de calcul a frequence infinie fonctionne bien lorsque les echelles d'energie sont relativement faibles. En d'autres termes, cette approche donne une bonne representation de S lorsque le systeme devient coherent. Les calculs montrent aussi que la formule Kelvin est precise lorsque la fonction spectrale des electrons devient incoherente, soit a plus haute temperature. Dans la limite Kelvin, S est essentiellement l'entropie par particule, tel que propose il y a longtemps. Nos resultats demontrent ainsi que la vision purement entropique de S est la bonne dans le regime incoherent, alors que dans le regime coherent, l'approche a frequence infinie est meilleure. Nous avons utilise une methode a la fine pointe, soit le Monte-Carlo quantique en temps continu pour resoudre la DMFT. Pour permettre une exploration rapide du diagramme de phase, nous avons du developper une nouvelle version de la methode des perturbations iterees pour qu'elle soit applicable aussi a forte interaction au-dela de la valeur critique de la transition de Mott. Un autre sujet a aussi ete aborde. L'effet orbital du champ magnetique dans les systemes electroniques fortement correles est une question tres importante et peu developpee. Cela est d'autant plus essentiel depuis la decouverte des oscillations quantiques dans les supraconducteurs a haute temperature (haut- Tc). Par desir de developper une methode la moins biaisee possible, nous avons derive la DMFT lorsqu'un champ se couplant a l'operateur energie cinetique par la substitution de Peierls est present. Ce type d'approche est necessaire pour comprendre entre autres l'effet de la physique de Mott sur des phenomenes tels que les oscillations quantiques. Nous avons obtenu un resultat tres important en demontrant rigoureusement que la relation d'auto-coherence de la DMFT et le systeme intermediaire d'impurete quantique restent les memes. L'effet du champ peut etre contenu dans la fonction de Green locale, ce qui constitue la grande difference avec le cas habituel. Ceci permet de continuer a utiliser les solutionneurs d'impuretes standards, qui sont de plus en plus puissants. Nous avons aussi developpe la methode pour le cas d'un empilement de plans bidimensionnels selon z, ce qui permet d'etudier l'effet orbital du champ dans des nanostructures et meme dans les materiaux massifs, si le nombre de plans est suffisant pour obtenir la limite tridimensionnelle. Mots cles : Pouvoir thermoelectrique, Theorie du Champ Moyen Dynamique, Modele de Hubbard, Effet orbital du champ magnetique, Electrons fortement correles, Materiaux quantiques, Theorie des perturbations iterees

Astigmatism-corrected echelle spectrometer using an off-the-shelf cylindrical lens.

PubMed

Fu, Xiao; Duan, Fajie; Jiang, Jiajia; Huang, Tingting; Ma, Ling; Lv, Changrong

2017-10-01

As a special kind of spectrometer with the Czerny-Turner structure, the echelle spectrometer features two-dimensional dispersion, which leads to a complex astigmatic condition. In this work, we propose an optical design of astigmatism-corrected echelle spectrometer using an off-the-shelf cylindrical lens. The mathematical model considering astigmatism introduced by the off-axis mirrors, the echelle grating, and the prism is established. Our solution features simplified calculation and low-cost construction, which is capable of overall compensation of the astigmatism in a wide spectral range (200-600 nm). An optical simulation utilizing ZEMAX software, astigmatism assessment based on Zernike polynomials, and an instrument experiment is implemented to validate the effect of astigmatism correction. The results demonstrated that astigmatism of the echelle spectrometer was corrected to a large extent, and high spectral resolution better than 0.1 nm was achieved.

Elaboration de nouvelles approches micromecaniques pour l'optimisation des performances mecaniques des materiaux heterogenes

NASA Astrophysics Data System (ADS)

Aboutajeddine, Ahmed

Les modeles micromecaniques de transition d'echelles qui permettent de determiner les proprietes effectives des materiaux heterogenes a partir de la microstructure sont consideres dans ce travail. L'objectif est la prise en compte de la presence d'une interphase entre la matrice et le renforcement dans les modeles micromecaniques classiques, de meme que la reconsideration des approximations de base de ces modeles, afin de traiter les materiaux multiphasiques. Un nouveau modele micromecanique est alors propose pour tenir compte de la presence d'une interphase elastique mince lors de la determination des proprietes effectives. Ce modele a ete construit grace a l'apport de l'equation integrale, des operateurs interfaciaux de Hill et de la methode de Mori-Tanaka. Les expressions obtenues pour les modules globaux et les champs dans l'enrobage sont de nature analytique. L'approximation de base de ce modele est amelioree par la suite dans un nouveau modele qui s'interesse aux inclusions enrobees avec un enrobage mince ou epais. La resolution utilisee s'appuie sur une double homogeneisation realisee au niveau de l'inclusion enrobee et du materiau. Cette nouvelle demarche, permettra d'apprehender completement les implications des approximations de la modelisation. Les resultats obtenus sont exploites par la suite dans la solution de l'assemblage de Hashin. Ainsi, plusieurs modeles micromecaniques classiques d'origines differentes se voient unifier et rattacher, dans ce travail, a la representation geometrique de Hashin. En plus de pouvoir apprecier completement la pertinence de l'approximation de chaque modele dans cette vision unique, l'extension correcte de ces modeles aux materiaux multiphasiques est rendue possible. Plusieurs modeles analytiques et explicites sont alors proposee suivant des solutions de differents ordres de l'assemblage de Hashin. L'un des modeles explicite apparait comme une correction directe du modele de Mori-Tanaka, dans les cas ou celui ci echoue a donner de bons resultats. Finalement, ce modele de Mori-Tanaka corrige est utilise avec les operateurs de Hill pour construire un modele de transition d'echelle pour les materiaux ayant une interphase elastoplastique. La loi de comportement effective trouvee est de nature incrementale et elle est conjuguee a la relation de la plasticite de l'interphase. Des simulations d'essais mecaniques pour plusieurs proprietes de l'interphase plastique a permis de dresser des profils de l'enrobage octroyant un meilleur comportement au materiau.

New On-Orbit Sensitivity Calibrationfor All STIS Echelle Modes

NASA Astrophysics Data System (ADS)

Aloisi, Alessandra; Bohlin, Ralph; Quijano, Jessica Kim

2007-01-01

On-orbit sensitivities for the 32 medium- and high-resolution STIS echelle secondarymodes were determined for the rst time using observations of the fundamental DAwhite dwarf standard star G191-B2B. Revised on-orbit sensitivities for the 12 mediumandhigh-resolution echelle prime modes based on observations of the same standardstar are also presented. We review the procedures and assumptions used to derive theadopted throughputs and implement them into the pipeline.

VizieR Online Data Catalog: WIYN open cluster study. LIX. RVs of NGC 6791 (Tofflemire+, 2014)

NASA Astrophysics Data System (ADS)

Tofflemire, B. M.; Gosnell, N. M.; Mathieu, R. D.; Platais, I.

2014-11-01

Our observations utilize the Hydra Multi-Object Spectrograph (MOS) on the WIYN 3.5m telescope. We use 3.1'' diameter fibers along with the bench spectrograph echelle grating, resulting in a spectral resolution of ~20000 (15km/s). See Geller et al. 2008 (cat. J/AJ/135/2264; Paper XXXII) for full details about our observing and data reduction procedures. Variations in our methods from previous WIYN Open Cluster Study (WOCS) radial velocity papers are given in Section 3. (3 data files).

Filtrage Lineaire par Morceaux Avec Petit Bruit d’Observation (Piecewise Linear Filtering with Small Observation Noise)

DTIC Science & Technology

1990-11-19

stir divers exemple-s le comportement des filtres l)r0pose5 par ra.)pDort ceux du processus estliner et dti filtre optimal obtenu de fa~on approch6e...Piecewise monotone filtering with small observation noise, Siam J., Control Optim. 20, 261-285, 1989 . Vii [10 W.ll. Fleming and R.W. Rishel...Milbeiro, de Oliveira : Filtres approch~s pour un probl~me de filtrage non lin~aire discret avec petit bruit d’observation,rapport INVRIA, 1142. 1989

Instrumentation progress at the Giant Magellan Telescope project

NASA Astrophysics Data System (ADS)

Jacoby, George H.; Bernstein, R.; Bouchez, A.; Colless, M.; Crane, Jeff; DePoy, D.; Espeland, B.; Hare, Tyson; Jaffe, D.; Lawrence, J.; Marshall, J.; McGregor, P.; Shectman, Stephen; Sharp, R.; Szentgyorgyi, A.; Uomoto, Alan; Walls, B.

2016-08-01

Instrument development for the 24m Giant Magellan Telescope (GMT) is described: current activities, progress, status, and schedule. One instrument team has completed its preliminary design and is currently beginning its final design (GCLEF, an optical 350-950 nm, high-resolution and precision radial velocity echelle spectrograph). A second instrument team is in its conceptual design phase (GMACS, an optical 350-950 nm, medium resolution, 6-10 arcmin field, multi-object spectrograph). A third instrument team is midway through its preliminary design phase (GMTIFS, a near-IR YJHK diffraction-limited imager/integral-field-spectrograph), focused on risk reduction prototyping and design optimization. A fourth instrument team is currently fabricating the 5 silicon immersion gratings needed to begin its preliminary design phase (GMTNIRS, a simultaneous JHKLM high-resolution, AO-fed, echelle spectrograph). And, another instrument team is focusing on technical development and prototyping (MANIFEST, a facility robotic, multifiber feed, with a 20 arcmin field of view). In addition, a medium-field (6 arcmin, 0.06 arcsec/pix) optical imager will support telescope and AO commissioning activities, and will excel at narrow-band imaging. In the spirit of advancing synergies with other groups, the challenges of running an ELT instrument program and opportunities for cross-ELT collaborations are discussed.

WIYN bench upgrade: a revitalized spectrograph

NASA Astrophysics Data System (ADS)

Bershady, M.; Barden, S.; Blanche, P.-A.; Blanco, D.; Corson, C.; Crawford, S.; Glaspey, J.; Habraken, S.; Jacoby, G.; Keyes, J.; Knezek, P.; Lemaire, P.; Liang, M.; McDougall, E.; Poczulp, G.; Sawyer, D.; Westfall, K.; Willmarth, D.

2008-07-01

We describe the redesign and upgrade of the versatile fiber-fed Bench Spectrograph on the WIYN 3.5m telescope. The spectrograph is fed by either the Hydra multi-object positioner or integral-field units (IFUs) at two other ports, and can be configured with an adjustable camera-collimator angle to use low-order and echelle gratings. The upgrade, including a new collimator, charge-coupled device (CCD) and modern controller, and volume-phase holographic gratings (VPHG), has high performance-to-cost ratio by combining new technology with a system reconfiguration that optimizes throughput while utilizing as much of the existing instrument as possible. A faster, all-refractive collimator enhances throughput by 60%, nearly eliminates the slit-function due to vignetting, and improves image quality to maintain instrumental resolution. Two VPH gratings deliver twice the diffraction efficiency of existing surface-relief gratings: A 740 l/mm grating (float-glass and post-polished) used in 1st and 2nd-order, and a large 3300 l/mm grating (spectral resolution comparable to the R2 echelle). The combination of collimator, high-quantum efficiency (QE) CCD, and VPH gratings yields throughput gain-factors of up to 3.5.

Post-SM4 Sensitivity Calibration of the STIS Echelle Modes

NASA Astrophysics Data System (ADS)

Bostroem, K. Azalee; Aloisi, A.; Bohlin, R.; Hodge, P.; Proffitt, C.

2012-01-01

On-orbit sensitivity curves for all echelle modes were derived for post - servicing mis- sion 4 data using observations of the DA white dwarf G191-B2B. Additionally, new echelle ripple tables and grating dependent bad pixel tables were created for the FUV and NUV MAMA. We review the procedures used to derive the adopted throughputs and implement them in the pipeline as well as the motivation for the modification of the additional reference files and pipeline procedures.

Unexpected series of regular frequency spacing of δ Scuti stars in the non-asymptotic regime. II. Sample-Echelle diagrams and rotation

DOE PAGES

Paparo, M.; Benko, J. M.; Hareter, M.; ...

2016-06-17

A sequence search method was developed for searching for regular frequency spacing in δ Scuti stars by visual inspection (VI) and algorithmic search. The sample contains 90 δ Scuti stars observed by CoRoT. An example is given to represent the VI. The algorithm (SSA) is described in detail. The data treatment of the CoRoT light curves, the criteria for frequency filtering, and the spacings derived by two methods (i.e., three approaches: VI, SSA, and FT) are given for each target. Echelle diagrams are presented for 77 targets for which at least one sequence of regular spacing was identified. Comparing the spacing and the shifts between pairs of echelle ridges revealed that at least one pair of echelle ridges is shifted to midway between the spacing for 22 stars. The estimated rotational frequencies compared to the shifts revealed rotationally split doublets, triplets, and multiplets not only for single frequencies, but for the complete echelle ridges in 31 δ Scuti stars. Furthermore, using several possible assumptions for the origin of the spacings, we derived the large separation (more » $${\\rm{\\Delta }}\

Unexpected series of regular frequency spacing of δ Scuti stars in the non-asymptotic regime. II. Sample-Echelle diagrams and rotation

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

Paparo, M.; Benko, J. M.; Hareter, M.

A sequence search method was developed for searching for regular frequency spacing in δ Scuti stars by visual inspection (VI) and algorithmic search. The sample contains 90 δ Scuti stars observed by CoRoT. An example is given to represent the VI. The algorithm (SSA) is described in detail. The data treatment of the CoRoT light curves, the criteria for frequency filtering, and the spacings derived by two methods (i.e., three approaches: VI, SSA, and FT) are given for each target. Echelle diagrams are presented for 77 targets for which at least one sequence of regular spacing was identified. Comparing the spacing and the shifts between pairs of echelle ridges revealed that at least one pair of echelle ridges is shifted to midway between the spacing for 22 stars. The estimated rotational frequencies compared to the shifts revealed rotationally split doublets, triplets, and multiplets not only for single frequencies, but for the complete echelle ridges in 31 δ Scuti stars. Furthermore, using several possible assumptions for the origin of the spacings, we derived the large separation (more » $${\\rm{\\Delta }}\

Battage de pieux métalliques dans la roche

NASA Astrophysics Data System (ADS)

Holeyman, Alain

2017-12-01

Le problème du battage d'un pieu tubulaire en acier dans un massif rocheux est abordé sous deux volets : numérique et expérimental. L'approche numérique par éléments finis couplant une modélisation lagrangienne du pieu en mouvement à une modélisation eulérienne du massif en place (approche CEL) permet de suivre l'émergence de la plastification dans le tube en acier en cours de pénétration, naissant en pointe pour se propager vers la tête du pieu. Un cas d'étude en conditions axisymétriques est présenté pour une roche dont la résistance à la compression simple σc vaut 28 MPa. L'approche expérimentale poursuivie en laboratoire a mis en jeu trois matériaux synthétisés sous la forme de monolithes dans lesquels le battage d'un tube en acier inoxydable a été entrepris. Les résultats de ces essais largement instrumentés indiquent que le battage est aisé dans un mortier cellulaire dont la résistance à la compression simple σc n'excède pas 6 MPa mais pratiquement impossible dans un mortier dont la résistance à la compression simple s'approche de 28 MPa. Le battage dans un mortier dont la résistance à la compression simple vaut 11 MPa s'est révélée encore faisable sous une hauteur de chute raisonnable. Les résultats obtenus avec les 3 matériaux mis en œuvre à ce jour indiquent que la résistance unitaire croît depuis environ 2 σc en surface pour atteindre 6 à 8 σc à une pénétration équivalente à 15-20 fois l'épaisseur du tube. Article introduit à la Revue française de Géotechnique en support à la Conférence Coulomb 2017 intitulée « Comportement axial des pieux sous sollicitations dynamiques extrêmes »

Le modele de Hubbard bidimensionnel a faible couplage: Thermodynamique et phenomenes critiques

NASA Astrophysics Data System (ADS)

Roy, Sebastien

Une etude systematique du modele de Hubbard en deux dimensions a faible couplage a l'aide de la theorie Auto-Coherente a Deux Particules (ACDP) dans le diagramme temperature-dopage-interaction-sauts permet de mettre en evidence l'influence des fluctuations magnetiques sur les proprietes thermodynamiques du systeme electronique sur reseau. Le regime classique renormalise a temperature finie pres du dopage nul est marque par la grandeur de la longueur de correlation de spin comparee a la longueur thermique de de Broglie et est caracterisee par un accroissement drastique de la longueur de correlation de spin. Cette croissance exponentielle a dopage nul marque la presence d'un pic de chaleur specifique en fonction de la temperature a basse temperature. Une temperature de crossover est alors associee a la temperature a laquelle la longueur de correlation de spin est egale a la longueur thermique de de Broglie. C'est a cette temperature caracteristique, ou est observee l'ouverture du pseudogap dans le poids spectral, que se situe le maximum du pic de chaleur specifique. La presence de ce pic a des consequences sur l'evolution du potentiel chimique avec le dopage lorsque l'uniformite thermodynamique est respectee. Les contraintes imposees par les lois de la thermodynamique font en sorte que l'evolution du potentiel chimique avec le dopage est non triviale. On demontre entre autres que le potentiel chimique est proportionnel a la double occupation qui est reliee au moment local. Par ailleurs, une derivation de la fonction de mise a l'echelle de la susceptibilite de spin a frequence nulle au voisinage d'un point critique marque sans equivoque la presence d'un point critique quantique en dopage pour une valeur donnee de l'interaction. Ce point critique, associe a une transition de phase magnetique en fonction du dopage a temperature nulle, induit un comportement non trivial sur les proprietes physiques du systeme a temperature finie. L'approche quantitative ACDP permet de calculer une echelle de temperature concrete pour laquelle ce point critique a des repercussions. Dans le regime critique, la longueur de correlation enregistre plutot une dependance en 1T Finalement, une synthese de ces resultats permet d'aborder une mise en application pratique de ces methodes d'analyse pour les supraconducteurs a haute temperature critique dopes aux electrons tels que le Nd2--xCe xCuO4+/-delta. Une comparaison entre les resultats theoriques et les mesures experimentales pour ce materiau est effectuee.

THE SOLAR NEIGHBORHOOD. XXVI. AP Col: THE CLOSEST (8.4 pc) PRE-MAIN-SEQUENCE STAR

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

Riedel, Adric R.; Henry, Todd J.; Jao, Wei-Chun

2011-10-15

We present the results of a multi-technique investigation of the M4.5Ve flare star AP Col, which we discover to be the nearest pre-main-sequence star. These include astrometric data from the CTIO 0.9 m, from which we derive a proper motion of 342.0 {+-} 0.5 mas yr{sup -1}, a trigonometric parallax of 119.21 {+-} 0.98 mas (8.39 {+-} 0.07 pc), and photometry and photometric variability at optical wavelengths. We also provide spectroscopic data, including radial velocity (22.4 {+-} 0.3 km s{sup -1}), lithium equivalent width (EW) (0.28 {+-} 0.02 A), H{alpha} EW (-6.0 to -35 A), vsin i (11 {+-} 1more » km s{sup -1}), and gravity indicators from the Siding Spring 2.3 m WiFeS, Lick 3 m Hamilton echelle, and Keck-I HIRES echelle spectrographs. The combined observations demonstrate that AP Col is the closer of only two known systems within 10 pc of the Sun younger than 100 Myr. Given its space motion and apparent age of 12-50 Myr, AP Col is likely a member of the recently proposed {approx}40 Myr old Argus/IC 2391 Association.« less

CERES: A Set of Automated Routines for Echelle Spectra

NASA Astrophysics Data System (ADS)

Brahm, Rafael; Jordán, Andrés; Espinoza, Néstor

2017-03-01

We present the Collection of Elemental Routines for Echelle Spectra (CERES). These routines were developed for the construction of automated pipelines for the reduction, extraction, and analysis of spectra acquired with different instruments, allowing the obtention of homogeneous and standardized results. This modular code includes tools for handling the different steps of the processing: CCD image reductions; identification and tracing of the echelle orders; optimal and rectangular extraction; computation of the wavelength solution; estimation of radial velocities; and rough and fast estimation of the atmospheric parameters. Currently, CERES has been used to develop automated pipelines for 13 different spectrographs, namely CORALIE, FEROS, HARPS, ESPaDOnS, FIES, PUCHEROS, FIDEOS, CAFE, DuPont/Echelle, Magellan/Mike, Keck/HIRES, Magellan/PFS, and APO/ARCES, but the routines can be easily used to deal with data coming from other spectrographs. We show the high precision in radial velocity that CERES achieves for some of these instruments, and we briefly summarize some results that have already been obtained using the CERES pipelines.

Interoperable Risk Management in a Joint Interagency Multinational Environment

DTIC Science & Technology

2007-08-01

est ensuite examinée par rapport à l’approche rendue obligatoire par le Conseil du Trésor. Un examen effectué par le Chef – Service d’examen (2004...relativement à la compréhension du MDN/des FC en matière de gestion des risques. De plus, un examen effectué par le Chef – Service d’examen (2004) a...to support further improvement. The Treasury Board of Canada Secretariat’s framework for risk management is also reflected in a companion

Cataclysmic variables. Recent multi-frequency observations and theoretical developments; Proceedings of the 93rd IAU Colloquium, Bamberg, West Germany, June 16-19, 1986

NASA Technical Reports Server (NTRS)

Drechsel, H. (Editor); Rahe, J. (Editor); Kondo, Y. (Editor)

1987-01-01

Papers are presented on the formation and evolution of low-mass close binaries with compact components, the periods of cataclysmic variables, multiwavelength observations of dwarf novae during outbursts, and radio emission from cataclysmic variables. Also considered are long-term optical photometry of the dwarf nova VW Hyi, periodic modulations in the optical light curves of EX Hydrae, and Echelle-Mepsicron time-resolved spectroscopy of the dwarf nova SS Cygni. Other topics include UV and X-ray observations of cataclysmic variables, new EXOSAT observations of TV Columbae, accretion disk evolution, and the boundary layer in cataclysmic variables.

The coude spectrograph and echelle scanner of the 2.7 m telescope at McDonald Observatory.

NASA Technical Reports Server (NTRS)

Tull, R. G.

1972-01-01

Discussion of certain design aspects of the coude spectrograph, and description of the coude scanner that uses some of the spectrograph optics. The configuration of the large echelle grating used is reviewed along with the systems of computer scanner control and data handling.

The Coude spectrograph and echelle scanner of the 2.7 m telescope at McDonald observatory

NASA Technical Reports Server (NTRS)

Tull, R. G.

1972-01-01

The design of the Coude spectrograph of the 2.7 m McDonald telescope is discussed. A description is given of the Coude scanner which uses the spectrograph optics, the configuration of the large echelle and the computer scanner control and data systems.

Optical design for CETUS: a wide-field 1.5m aperture UV payload being studied for a NASA probe class mission study

NASA Astrophysics Data System (ADS)

Woodruff, Robert A.; Hull, Tony; Heap, Sara R.; Danchi, William; Kendrick, Stephen E.; Purves, Lloyd

2017-09-01

We are developing a NASA Headquarters selected Probe-class mission concept called the Cosmic Evolution Through UV Spectroscopy (CETUS) mission, which includes a 1.5-m aperture diameter large field-of-view (FOV) telescope optimized for UV imaging, multi-object spectroscopy, and point-source spectroscopy. The optical system includes a Three Mirror Anastigmatic (TMA) telescope that simultaneously feeds three separate scientific instruments: the near-UV (NUV) Multi-Object Spectrograph (MOS) with a next-generation Micro-Shutter Array (MSA); the two-channel camera covering the far-UV (FUV) and NUV spectrum; and the point-source spectrograph covering the FUV and NUV region with selectable R 40,000 echelle modes and R 2,000 first order modes. The optical system includes fine guidance sensors, wavefront sensing, and spectral and flat-field in-flight calibration sources. This paper will describe the current optical design of CETUS.

Optical design for CETUS: a wide-field 1.5m aperture UV payload being studied for a NASA probe class mission study

NASA Astrophysics Data System (ADS)

Woodruff, Robert; Robert Woodruff, Goddard Space Flight Center, Kendrick Optical Consulting

2018-01-01

We are developing a NASA Headquarters selected Probe-class mission concept called the Cosmic Evolution Through UV Spectroscopy (CETUS) mission, which includes a 1.5-m aperture diameter large field-of-view (FOV) telescope optimized for UV imaging, multi-object spectroscopy, and point-source spectroscopy. The optical system includes a Three Mirror Anastigmatic (TMA) telescope that simultaneously feeds three separate scientific instruments: the near-UV (NUV) Multi-Object Spectrograph (MOS) with a next-generation Micro-Shutter Array (MSA); the two-channel camera covering the far-UV (FUV) and NUV spectrum; and the point-source spectrograph covering the FUV and NUV region with selectable R~ 40,000 echelle modes and R~ 2,000 first order modes. The optical system includes fine guidance sensors, wavefront sensing, and spectral and flat-field in-flight calibration sources. This paper will describe the current optical design of CETUS.

Optical Alignment and Diffraction Analysis for AIRES: An Airborne Infrared Echelle Spectrometer

NASA Technical Reports Server (NTRS)

Haas, Michael R.; Fonda, Mark (Technical Monitor)

2002-01-01

The optical design is presented for a long-slit grating spectrometer known as AIRES (Airborne InfraRed Echelle Spectrometer). The instrument employs two gratings in series: a small order sorter and a large steeply blazed echelle. The optical path includes four pupil and four field stops, including two narrow slits. A detailed diffraction analysis is performed using GLAD by Applied Optics Research to evaluate critical trade-offs between optical throughput, spectral resolution, and system weight and volume. The effects of slit width, slit length, oversizing the second slit relative to the first, on- vs off-axis throughput, and clipping at the pupil stops and other optical elements are discussed.

The ICE spectrograph for PEPSI at the LBT: preliminary optical design

NASA Astrophysics Data System (ADS)

Pallavicini, Roberto; Zerbi, Filippo M.; Spano, Paolo; Conconi, Paolo; Mazzoleni, Ruben; Molinari, Emilio; Strassmeier, Klaus G.

2003-03-01

We present a preliminary design study for a high-resolution echelle spectrograph (ICE) to be used with the spectropolarimeter PEPSI under development at the LBT. In order to meet the scientific requirements and take full advantage of the peculiarities of the LBT (i.e. the binocular nature and the adaptive optics capabilities), we have designed a fiber-fed bench mounted instrument for both high resolution (R ≍ 100,000; non-AO polarimetric and integral light modes) and ultra-high resolution (R ≍ 300,000; AO integral light mode). In both cases, 4 spectra per order (two for each primary mirror) shall be accomodated in a 2-dimensional cross dispersed echelle format. In order to obtain a resolution-slit product of ≍ 100,000 as required by the science case, we have considered two alternative designs, one with two R4 echelles in series and the other with a sigle R4 echelle and fiber slicing. A white-pupil design, VPH cross-dispersers and two cameras of different focal length for the AO and non-AO modes are adopted in both cases. It is concluded that the single-echelle fiber-slicer solution has to be preferred in terms of performances, complexity and cost. It can be implemented at the LBT in two phases, with the long-camera AO mode added in a second phase depending on the availability of funds and the time-scale for implementation of the AO system.

Validation materielle d'une architecture generique de reseaux avioniques basee sur une gestion modulaire de la redondance

NASA Astrophysics Data System (ADS)

Tremblay, Jose-Philippe

Les systemes avioniques ne cessent d'evoluer depuis l'apparition des technologies numeriques au tournant des annees 60. Apres le passage par plusieurs paradigmes de developpement, ces systemes suivent maintenant l'approche " Integrated Modular Avionics " (IMA) depuis le debut des annees 2000. Contrairement aux methodes anterieures, cette approche est basee sur une conception modulaire, un partage de ressources generiques entre plusieurs systemes et l'utilisation plus poussee de bus multiplexes. La plupart des concepts utilises par l'architecture IMA, bien que deja connus dans le domaine de l'informatique distribuee, constituent un changement marque par rapport aux modeles anterieurs dans le monde avionique. Ceux-ci viennent s'ajouter aux contraintes importantes de l'avionique classique telles que le determinisme, le temps reel, la certification et les cibles elevees de fiabilite. L'adoption de l'approche IMA a declenche une revision de plusieurs aspects de la conception, de la certification et de l'implementation d'un systeme IMA afin d'en tirer profit. Cette revision, ralentie par les contraintes avioniques, est toujours en cours, et offre encore l'opportunite de developpement de nouveaux outils, methodes et modeles a tous les niveaux du processus d'implementation d?un systeme IMA. Dans un contexte de proposition et de validation d'une nouvelle architecture IMA pour un reseau generique de capteurs a bord d?un avion, nous avons identifie quelques aspects des differentes approches traditionnelles pour la realisation de ce type d?architecture pouvant etre ameliores. Afin de remedier a certaines des differentes lacunes identifiees, nous avons propose une approche de validation basee sur une plateforme materielle reconfigurable ainsi qu'une nouvelle approche de gestion de la redondance pour l'atteinte des cibles de fiabilite. Contrairement aux outils statiques plus limites satisfaisant les besoins pour la conception d'une architecture federee, notre approche de validation est specifiquement developpee de maniere a faciliter la conception d'une architecture IMA. Dans le cadre de cette these, trois axes principaux de contributions originales se sont degages des travaux executes suivant les differents objectifs de recherche enonces precedemment. Le premier axe se situe au niveau de la proposition d'une architecture hierarchique de reseau de capteurs s'appuyant sur le modele de base de la norme IEEE 1451. Cette norme facilite l'integration de capteurs et actuateurs intelligents a tout systeme de commande par des interfaces normalisees et generiques.

VizieR Online Data Catalog: Abundance distribution of stars with planets (Bond+, 2006)

NASA Astrophysics Data System (ADS)

Bond, J. C.; Tinney, C. G.; Butler, R. P.; Jones, H. R. A.; Marcy, G. W.; Penny, A. J.; Carter, B. D.

2006-11-01

Spectroscopic observations of the target stars were obtained at the 3.9-m Anglo-Australian Telescope (AAT) between 1998 January and 2000 November as part of the AAPS. All of the spectra used were obtained with the University College London Echelle Spectrograph using the 31.6lines/mm echelle grating. (2 data files).

Unexpected effects of a trap in CCD echelle spectra of B-type stars

NASA Technical Reports Server (NTRS)

Morrison, Nancy D.; Zimba, Jason R.

1990-01-01

Because of the nature of echelle spectra, cosmetic defects such as traps may mimic real spectral features. An example from spectra taken at CTIO with a GEC CCD is presented, and it is shown how the affected pixels can be eliminated from the reduced spectrum, at a slight cost in signal-to-noise ratio.

GHRS Cycle 5 Echelle Wavelength Monitor

NASA Astrophysics Data System (ADS)

Soderblom, David

1995-07-01

This proposal defines the spectral lamp test for Echelle A. It is an internal test which makes measurements of the wavelength lamp SC2. It calibrates the carrousel function, Y deflections, resolving power, sensitivity, and scattered light. The wavelength calibration dispersion constants will be updated in the PODPS calibration data base. This proposal defines the spectral lamp test for Echelle B. It is an internal test which makes measurements of the wavelength lamp SC2. It calibrates the carrousel function, Y deflections, resolving power, sensitivity, and scattered light. The wavelength calibration dispersion constants will be updated in the PODPS calibration data base. It will be run every 4 months. The wavelengths may be out of range according to PEPSI or TRANS. Please ignore the errors.

Multi-resolution waveguide image slicer for the PEPSI instrument

NASA Astrophysics Data System (ADS)

Beckert, Erik; Strassmeier, Klaus G.; Woche, Manfred; Harnisch, Gerd; Hornaff, Marcel; Weber, Michael; Barnes, Stuart

2016-07-01

A waveguide image slicer with resolutions up to 270.000 (planned: 300.000) for the fiber fed PEPSI echelle spectrograph at the LBT and single waveguide thicknesses of down to 70 μm has been manufactured and tested. The waveguides were macroscopically prepared, stacked up to an order of seven and thinned back to square stack cross sections. A high filling ratio was achieved by realizing homogenous adhesive gaps of 3.6 μm, using index matching adhesives for TIR within the waveguides. The image slicer stacks are used in immersion mode and are miniaturized to enable implementation in a set of 2x8. The overall efficiency is between 92 % and 96 %.

ORAC-DR: One Pipeline for Multiple Telescopes

NASA Astrophysics Data System (ADS)

Cavanagh, B.; Hirst, P.; Jenness, T.; Economou, F.; Currie, M. J.; Todd, S.; Ryder, S. D.

ORAC-DR, a flexible and extensible data reduction pipeline, has been successfully used for real-time data reduction from UFTI and IRCAM (infrared cameras), CGS4 (near-infrared spectrometer), Michelle (mid-infrared imager and echelle spectrometer), at UKIRT; and SCUBA (sub-millimeter bolometer array) at JCMT. We have now added the infrared imaging spectrometers IRIS2 at the Anglo-Australian Telescope and UIST at UKIRT to the list of officially supported instruments. We also present initial integral field unit support for UIST, along with unofficial support for the imager and multi-object spectrograph GMOS at Gemini. This paper briefly describes features of the pipeline along with details of adopting ORAC-DR for other instruments on telescopes around the world.

LE MAINTIEN DU POUVOIR CHEZ LA PERSONNE ÂGÉE HÉBERGÉE SOUFFRANT DE DÉFICITS COGNITIFS

PubMed Central

Vézina, Aline; Pelletier, Daniel

2013-01-01

Cet article théorique interpelle à la fois la recherche et l’intervention, à l’égard du mieux-être des personnes âgées hébergées présentant des troubles cognitifs associés à des démences dégénératives. Appuyé par la perspective de l’interactionnisme symbolique, il met l’accent sur les interactions entre le personnel soignant (infirmière, infirmière auxiliaire, préposée, ergothérapeute, personnel de réadaptation et des loisirs, travailleuse sociale, etc.) et les proches aidants, dans un objectif de maintien du pouvoir pour et par la personne âgée. Sous l’angle de l’approche centrée sur la personne, qui affirme l’importance de dépasser l’âgisme et l’impuissance quant à la démence, il aborde deux approches : l’approche prothétique élargie et l’approche biographique qui permettent de soutenir l’identité et l’affirmation de soi de la personne âgée hébergée souffrant de déficits cognitifs. PMID:24795486

A Python Script for Aligning the STIS Echelle Blaze Function

NASA Astrophysics Data System (ADS)

Baer, Malinda; Proffitt, Charles R.; Lockwood, Sean A.

2018-01-01

Accurate flux calibration for the STIS echelle modes is heavily dependent on the proper alignment of the blaze function for each spectral order. However, due to changes in the instrument alignment over time and between exposures, the blaze function can shift in wavelength. This may result in flux calibration inconsistencies of up to 10%. We present the stisblazefix Python module as a tool for STIS users to correct their echelle spectra. The stisblazefix module assumes that the error in the blaze alignment is a linear function of spectral order, and finds the set of shifts that minimizes the flux inconsistencies in the overlap between spectral orders. We discuss the uses and limitations of this tool, and show that its use can provide significant improvements to the default pipeline flux calibration for many observations.

Vector magnetic field observations with the Haleakala polarimeter

NASA Technical Reports Server (NTRS)

Mickey, D. L.

1985-01-01

Several enhancements were recently made to the Haleakala polarimeter. Linear array detectors provide simultaneous resolution over a 3-A wavelength range, with spectral resolution of 40 mA. Optical fibers are now used to carry the intensity-modulated light from the rotating quarter-wave plate polarimeter to the echelle spectrometer, permitting its removal from the spar to a more stable environment. These changes, together with improved quarter-wave plates, reduced systematic errors to a few parts in 10,000 for routine observations. Examples of Stokes profiles and derived magnetic field maps are presented.

MIRADAS control system

NASA Astrophysics Data System (ADS)

Rosich Minguell, Josefina; Garzón Lopez, Francisco

2012-09-01

The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS, a near-infrared multi-object echelle spectrograph operating at spectral resolution R=20,000 over the 1-2.5μm bandpass) was selected in 2010 by the Gran Telescopio Canarias (GTC) partnership as the next-generation near-infrared spectrograph for the world's largest optical/infrared telescope, and is being developed by an international consortium. The MIRADAS consortium includes the University of Florida, Universidad de Barcelona, Universidad Complutense de Madrid, Instituto de Astrofísica de Canarias, Institut de Física d'Altes Energies, Institut d'Estudis Espacials de Catalunya and Universidad Nacional Autónoma de México. This paper shows an overview of the MIRADAS control software, which follows the standards defined by the telescope to permit the integration of this software on the GTC Control System (GCS). The MIRADAS Control System is based on a distributed architecture according to a component model where every subsystem is selfcontained. The GCS is a distributed environment written in object oriented C++, which runs components in different computers, using CORBA middleware for communications. Each MIRADAS observing mode, including engineering, monitoring and calibration modes, will have its own predefined sequence, which are executed in the GCS Sequencer. These sequences will have the ability of communicating with other telescope subsystems.

The re-flight of the Colorado high-resolution Echelle stellar spectrograph (CHESS): improvements, calibrations, and post-flight results

NASA Astrophysics Data System (ADS)

Hoadley, Keri; France, Kevin; Kruczek, Nicholas; Fleming, Brian; Nell, Nicholas; Kane, Robert; Swanson, Jack; Green, James; Erickson, Nicholas; Wilson, Jacob

2016-07-01

In this proceeding, we describe the scientific motivation and technical development of the Colorado High- resolution Echelle Stellar Spectrograph (CHESS), focusing on the hardware advancements and testing supporting the second flight of the payload (CHESS-2). CHESS is a far ultraviolet (FUV) rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium (ISM). CHESS is an objective f/12.4 echelle spectrograph with resolving power > 100,000 over the band pass 1000 - 1600 Å. The spectrograph was designed to employ an R2 echelle grating with "low" line density. We compare the FUV performance of experimental echelle etching processes (lithographically by LightSmyth, Inc. and etching via electron-beam technology by JPL Microdevices Laboratory) with traditional, mechanically-ruled gratings (Bach Research, Inc. and Richardson Gratings). The cross-dispersing grating, developed and ruled by Horiba Jobin-Yvon, is a holographically-ruled, "low" line density, powered optic with a toroidal surface curvature. Both gratings were coated with aluminum and lithium fluoride (Al+LiF) at Goddard Space Flight Center (GSFC). Results from final efficiency and reflectivity measurements for the optical components of CHESS-2 are presented. CHESS-2 utilizes a 40mm-diameter cross-strip anode readout microchannel plate (MCP) detector fabricated by Sensor Sciences, Inc., to achieve high spatial resolution with high count rate capabilities (global rates 1 MHz). We present pre-flight laboratory spectra and calibration results. CHESS-2 launched on 21 February 2016 aboard NASA/CU sounding rocket mission 36.297 UG. We observed the intervening ISM material along the sightline to epsilon Per and present initial characterization of the column densities, temperature, and kinematics of atomic and molecular species in the observation.

ZEUS-2: a second generation submillimeter grating spectrometer for exploring distant galaxies

NASA Astrophysics Data System (ADS)

Ferkinhoff, Carl; Nikola, Thomas; Parshley, Stephen C.; Stacey, Gordon J.; Irwin, Kent D.; Cho, Hsiao-Mei; Halpern, Mark

2010-07-01

ZEUS-2, the second generation (z)Redshift and Early Universe Spectrometer, like its predecessor is a moderate resolution (R~1000) long-slit, echelle grating spectrometer optimized for the detection of faint, broad lines from distant galaxies. It is designed for studying star-formation across cosmic time. ZEUS-2 employs three TES bolometer arrays (555 pixels total) to deliver simultaneous, multi-beam spectra in up to 4 submillimeter windows. The NIST Boulder-built arrays operate at ~100mK and are readout via SQUID multiplexers and the Multi-Channel Electronics from the University of British Columbia. The instrument is cooled via a pulse-tube cooler and two-stage ADR. Various filter configurations give ZEUS-2 access to 7 different telluric windows from 200 to 850 micron enabling the simultaneous mapping of lines from extended sources or the simultaneous detection of the 158 micron [CII] line and the [NII] 122 or 205 micron lines from z = 1-2 galaxies. ZEUS-2 is designed for use on the CSO, APEX and possibly JCMT.

High efficiency spectrographs for the EUV and soft X-rays

NASA Technical Reports Server (NTRS)

Cash, W.

1983-01-01

The use of grazing incidence optics and reflection grating designs is shown to be a method that improves the performance of spectrographs at wavelengths shorter than 1200 A. Emphasis is laid on spectroscopic designs for X ray and EUV astronomy, with sample designs for an objective reflection grating spectrograph (ORGS) and an echelle spectrograph for wavelengths longer than 100 A. Conical diffraction allows operations at grazing incidence in the echelle spectrograph. In ORGS, the extreme distance of X ray objects aids in collimating the source radiation, which encounters conical diffraction within the instrument, proceeds parallel to the optical axis, and arrives at the detector. A series of gratings is used to achieve the effect. A grazing echelle is employed for EUV observations, and offers a resolution of 20,000 over a 300 A bandpass.

GUIs in the MIDAS environment

NASA Technical Reports Server (NTRS)

Ballester, P.

1992-01-01

MIDAS (Munich Image Data Analysis System) is the image processing system developed at ESO for astronomical data reduction. MIDAS is used for off-line data reduction at ESO and many astronomical institutes all over Europe. In addition to a set of general commands, enabling to process and analyze images, catalogs, graphics and tables, MIDAS includes specialized packages dedicated to astronomical applications or to specific ESO instruments. Several graphical interfaces are available in the MIDAS environment: XHelp provides an interactive help facility, and XLong and XEchelle enable data reduction of long-slip and echelle spectra. GUI builders facilitate the development of interfaces. All ESO interfaces comply to the ESO User Interfaces Common Conventions which secures an identical look and feel for telescope operations, data analysis, and archives.

Approaches to the Implementation of Environment Pollution Prevention Technologies at Military Bases (Approches de l’application des techniques de prevention de la pollution sur les bases militaires)

DTIC Science & Technology

2000-04-01

The objective is to support the development and effective use of national defence research and technology and to meet the military needs of the...on materials and energy through developing an effective management system. There are many definitions to describe environmental auditing. I would...anthropogenic increase of CH4 (e.g., from rice fields). Therefore the net effect of aircraft is a negative RF due to the CH4 changes: -0.014 Wm" 2 in 1992

An Externally Dispersed Interferometer for Sensitive Doppler Extrasolar Planet Searches

NASA Astrophysics Data System (ADS)

Ge, Jian; Erskine, David J.; Rushford, Mike

2002-09-01

A new kind of instrument for sensitive Doppler extrasolar planet searches, called an externally dispersed interferometer, is described in this paper. It is a combination of an optical Michelson-type interferometer and an intermediate-resolution grating spectrometer. The interferometer measures Doppler radial velocity (RV) variations of starlight through the phase shifts of moiré fringes, created by multiplication of the interferometer fringes with stellar absorption lines. The intermediate-resolution spectrograph disperses the moiré fringes into thousands of parallel-wavelength channels. This increases the instrument bandwidth and fringe visibility by preventing fringe cross-talk between neighboring spectral lines. This results in a net increase in the signal-to-noise ratio over an interferometer used alone with broadband light. Compared to current echelle spectrometers for extrasolar planet searches, this instrument offers two unique instrument properties: a simple, stable, well-defined sinusoidal instrument response function (point-spread function) and magnification of Doppler motion through moiré fringe techniques. Since instrument noise is chiefly limited by the ability to characterize the instrument response, this new technique provides unprecedented low instrumental noise in an economical compact apparatus, enabling higher precision for Doppler RV measurements. In practice, the moiré magnification can be 5-10 times depending on the interferometer comb angle. This instrument has better sensitivity for smaller Doppler shifts than echelle spectrometers. The instrument can be designed with much lower spectral resolving power without losing Doppler sensitivity and optimized for higher throughput than echelle spectrometers to allow a potential survey for planets around fainter stars than current magnitude limits. Lab-based experiments with a prototype instrument with a spectral resolution of R~20,000 demonstrated ~0.7 m s-1 precision for short-term RV measurements. A fiber-fed version of the prototype with R~5600 was tested with starlight at the Lick 1 m telescope and demonstrated ~7 m s-1 RV precision at 340 Å bandwidth. The increased velocity noise is attributed to the lower spectral resolution, lower fringe visibility, and uncontrolled instrument environment.

Total reduction of distorted echelle spectrograms - An automatic procedure. [for computer controlled microdensitometer

NASA Technical Reports Server (NTRS)

Peterson, R. C.; Title, A. M.

1975-01-01

A total reduction procedure, notable for its use of a computer-controlled microdensitometer for semi-automatically tracing curved spectra, is applied to distorted high-dispersion echelle spectra recorded by an image tube. Microdensitometer specifications are presented and the FORTRAN, TRACEN and SPOTS programs are outlined. The intensity spectrum of the photographic or electrographic plate is plotted on a graphic display. The time requirements are discussed in detail.

Establishment and correction of an Echelle cross-prism spectrogram reduction model

NASA Astrophysics Data System (ADS)

Zhang, Rui; Bayanheshig; Li, Xiaotian; Cui, Jicheng

2017-11-01

The accuracy of an echelle cross-prism spectrometer depends on the matching degree between the spectrum reduction model and the actual state of the spectrometer. However, the error of adjustment can change the actual state of the spectrometer and result in a reduction model that does not match. This produces an inaccurate wavelength calibration. Therefore, the calibration of a spectrogram reduction model is important for the analysis of any echelle cross-prism spectrometer. In this study, the spectrogram reduction model of an echelle cross-prism spectrometer was established. The image position laws of a spectrometer that varies with the system parameters were simulated to the influence of the changes in prism refractive index, focal length and so on, on the calculation results. The model was divided into different wavebands. The iterative method, least squares principle and element lamps with known characteristic wavelength were used to calibrate the spectral model in different wavebands to obtain the actual values of the system parameters. After correction, the deviation of actual x- and y-coordinates and the coordinates calculated by the model are less than one pixel. The model corrected by this method thus reflects the system parameters in the current spectrometer state and can assist in accurate wavelength extraction. The instrument installation and adjustment would be guided in model-repeated correction, reducing difficulty of equipment, respectively.

EGRAM- ECHELLE SPECTROGRAPH DESIGN AID

NASA Technical Reports Server (NTRS)

Dantzler, A. A.

1994-01-01

EGRAM aids in the design of spectrographic systems that utilize an echelle-first order cross disperser combination. This optical combination causes a two dimensional echellogram to fall on a detector. EGRAM describes the echellogram with enough detail to allow the user to effectively judge the feasibility of the spectrograph's design. By iteratively altering system parameters, the desired echellogram can be achieved without making a physical model. EGRAM calculates system parameters which are accurate to the first order and compare favorably to results from ray tracing techniques. The spectrographic system modelled by EGRAM consists of an entrance aperture, collimator, echelle, cross dispersion grating, focusing options, and a detector. The system is assumed to be free of aberrations and the echelle, cross disperser, and detector should be planar. The EGRAM program is menu driven and has a HELP facility. The user is prompted for information such as minimum and maximum wavelengths, slit dimensions, ruling frequencies, detector geometry, and angle of incidence. EGRAM calculates the resolving power and range of order numbers covered by the echellogram. A numerical map is also produced. This tabulates the order number, slit bandpass, and high/middle/low wavelengths. EGRAM can also compute the centroid coordinates of a specific wavelength and order (or vice versa). EGRAM is written for interactive execution and is written in Microsoft BASIC A. It has been implemented on an IBM PC series computer operating under DOS. EGRAM was developed in 1985.

Conception de lois de pilotage robustes et sequencement de gains par l'approche de systemes lineaires a parametres variants

NASA Astrophysics Data System (ADS)

Hentabli, Kamel

Cette recherche s'inscrit dans le cadre du projet de recherche Active Control Technology entre l'Ecole de Technologie Superieure et le constructeur Bombardier Aeronautique . Le but est de concevoir des strategies de commandes multivariables et robustes pour des modeles dynamiques d'avions. Ces strategies de commandes devraient assurer a l'avion une haute performance et satisfaire des qualites de vol desirees en l'occurrence, une bonne manoeuvrabilite, de bonnes marges de stabilite et un amortissement des mouvements phugoides et rapides de l'avion. Dans un premier temps, nous nous sommes principalement interesses aux methodes de synthese LTI et plus exactement a l'approche Hinfinity et la mu-synthese. Par la suite, nous avons accorde un interet particulier aux techniques de commande LPV. Pour mener a bien ce travail, nous avons envisage une approche frequentielle, typiquement Hinfinity. Cette approche est particulierement interessante, dans la mesure ou le modele de synthese est construit directement a partir des differentes specifications du cahier des charges. En effet, ces specifications sont traduites sous forme de gabarits frequentiels, correspondant a des ponderations en entree et en sortie que l'on retrouve dans la synthese Hinfinity classique. Par ailleurs, nous avons utilise une representation de type lineaire fractionnelle (LFT), jugee mieux adaptee pour la prise en compte des differents types d'incertitudes, qui peuvent intervenir sur le systeme. De plus, cette representation s'avere tres appropriee pour l'analyse de la robustesse via les outils de la mu-analyse. D'autre part, afin d'optimiser le compromis entre les specifications de robustesse et de performance, nous avons opte pour une structure de commande a 2 degres de liberte avec modele de reference. Enfin, ces techniques sont illustrees sur des applications realistes, demontrant ainsi la pertinence et l'applicabilite de chacune d'elle. Mots cles. Commande de vol, qualites de vol et manoeuvrabilite, commande robuste, approche Hinfinity , mu-synthese, systemes lineaires a parametres variants, sequencement de gains, transformation lineaire fractionnelle, inegalite matricielle lineaire.

Approche structurée en pratique familiale pour les patients ayant des problèmes de mémoire

PubMed Central

Lee, Linda; Weston, W. Wayne; Heckman, George; Gagnon, Micheline; Lee, F. Joseph; Sloka, Scott

2013-01-01

Résumé Objectif Présenter aux médecins de famille une approche structurée pour les patients qui présentent des problèmes de mémoire. Sources des données Cette approche se fonde sur un programme agréé de formation clinique sur la mémoire, élaboré par le Centre for Family Medicine Memory Clinic en partenariat avec le Collège des médecins de famille de l’Ontario. Message principal Le recours à une approche structurée de raisonnement clinique peut aider les médecins à poser un diagnostic exact chez des patients qui présentent des problèmes de mémoire. Le délirium, la dépression et les causes réversibles doivent être exclus, pour ensuite faire une différenciation entre le vieillissement cognitif normal, la déficience cognitive légère et la démence. Il est essentiel de procéder à une anamnèse collatérale et à une évaluation fonctionnelle exacte. Les formes courantes de la démence peuvent être cliniquement différenciées par la séquence dans laquelle les symptômes apparaissent et par la façon dont les déficits cognitifs évoluent avec le temps. Habituellement, les signes précoces de la démence d’Alzheimer comportent une déficience de la mémoire épisodique, tandis que la démence due principalement à des causes vasculaires peut se présenter par une perte précoce de la fonction exécutive et de la fonction visuospatiale, ainsi que des caractéristiques cliniques particulières. Conclusion Une approche de raisonnement clinique peut aider les médecins à poser des diagnostics précoces et exacts qui peuvent orienter une prise en charge appropriée et améliorer les soins aux patients qui ont des problèmes de mémoire.

The third flight of CHESS: Preliminary analysis of interstellar H2 on the β1 Sco sightline

NASA Astrophysics Data System (ADS)

Kruczek, Nick; France, Kevin

2018-01-01

We describe the scientific motivation and technical development of the Colorado High-resolution Echelle Stellar Spectrograph (CHESS), focusing on the preliminary science results for the third launch of the payload (CHESS-3). CHESS is a far ultraviolet rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium. CHESS is an objective echelle spectrograph, which uses a mechanically-ruled echelle and a powered (f/12.4) cross-dispersing grating, and is designed to achieve a resolving power R > 100,000 over the band pass λλ 1000-1600 Å. CHESS-3 launched on 14 June 2017 aboard NASA/CU sounding rocket mission 36.323 UG. The target for the flight was β1 Sco, a B1V star with a sightline that is likely sampling translucent material. We present flight results of interstellar molecular hydrogen excitation, including initial measurements of the column density and temperature, on the sightline.

Automated Software Generation Approaches for the Design and Development of Guidance and Control Systems Software (Les Differentes Approches Generation pour la Conception et le Developpement de Logiciels de Guidage et de Pilotage)

DTIC Science & Technology

1992-03-01

de Logiciels") etaient en cours de developpement pour resoudre des problimes similaires dans le monde de la gestion . le Panel... gestion des sp cifications, d’algorithmes et de reprtsentations. Techniques et Sciences Informatiques, 4(3), 1985. 4-21 R. Jacquart, M. Lemoine, and G...Guidance and Control Systems Software (Les Diff~rentes Approches "G6neration" pour la Conception et le D~veloppement de Logiciels de Guidage et de

The optical design of the G-CLEF Spectrograph: the first light instrument for the GMT

NASA Astrophysics Data System (ADS)

Ben-Ami, Sagi; Epps, Harland; Evans, Ian; Mueller, Mark; Podgorski, William; Szentgyorgyi, Andrew

2016-08-01

The GMT-Consortium Large Earth Finder (G-CLEF), the first major light instrument for the GMT, is a fiber-fed, high-resolution echelle spectrograph. In the following paper, we present the optical design of G-CLEF. We emphasize the unique solutions derived for the spectrograph fiber-feed: the Mangin mirror that corrects the cylindrical field curvature, the implementation of VPH grisms as cross dispersers, and our novel solution for a multi-colored exposure meter. We describe the spectrograph blue and red cameras comprised of 7 and 8 elements respectively, with one aspheric surface in each camera, and present the expected echellogram imaged on the instrument focal planes. Finally, we present ghost analysis and mitigation strategy that takes into account both single reflection and double reflection back scattering from various elements in the optical train.

Radial velocity confirmation of Kepler-91 b. Additional evidence of its planetary nature using the Calar Alto/CAFE instrument

NASA Astrophysics Data System (ADS)

Lillo-Box, J.; Barrado, D.; Henning, Th.; Mancini, L.; Ciceri, S.; Figueira, P.; Santos, N. C.; Aceituno, J.; Sánchez, S. F.

2014-08-01

The object transiting the star Kepler-91 was recently assessed as being of planetary nature. The confirmation was achieved by analysing the light-curve modulations observed in the Kepler data. However, quasi-simultaneous studies claimed a self-luminous nature for this object, thus rejecting it as a planet. In this work, we apply anindependent approach to confirm the planetary mass of Kepler-91b by using multi-epoch high-resolution spectroscopy obtained with the Calar Alto Fiber-fed Echelle spectrograph (CAFE). We obtain the physical and orbital parameters with the radial velocity technique. In particular, we derive a value of 1.09 ± 0.20 MJup for the mass of Kepler-91b, in excellent agreement with our previous estimate that was based on the orbital brightness modulation.

VizieR Online Data Catalog: Infrared spectroscopy of symbiotic stars. XI. (Fekel+, 2017)

NASA Astrophysics Data System (ADS)

Fekel, F. C.; Hinkle, K. H.; Joyce, R. R.; Wood, P. R.

2017-06-01

Our spectroscopic observations in the southern hemisphere were initially acquired from 2001 March through 2002 December. We observed at the Mount Stromlo Observatory (MSO), which is located near Canberra, Australia, and used the 1.88m telescope and coude spectrograph. The detector to record our spectra was an infrared camera, NICMASS, that was developed at the University of Massachusetts. It produced a 2 pixel resolving power of 44000 at a wavelength of 1.623μm. Between 2003 February and 2010 June we obtained some additional spectra with the 8m Gemini South telescope, located at Cerro Pachon, Chile. We used the Phoenix cryogenic echelle spectrograph. That spectrograph enabled us to observe at several different infrared wavelength regions including 1.563, 2.226, and 2.364μm, and the Gemini South spectra have a resolving power equal to either 50000 or 70000. >From 2009 May through 2010 June we also used the 1.5m telescope at the Cerro Tololo Inter-American Observatory (CTIO). That telescope is operated by the Small and Moderate Aperature Research Telescope System (SMARTS) consortium of universities and other organizations. During that time period, we acquired five spectra with the 1.5m telescope, a fiber fed echelle spectrograph, and a 2K SITe CCD. The spectra have a resolving power of ~25000 at 5500Å. The echelle spectrograms from the 1.5m SMARTS telescope cover the wavelength range 4020-7300Å. We chose to measure velocities in one of the reddest orders of the SMARTS echelle spectrograms at a wavelength region near 7130Å. (5 data files).

Pulsations in the atmosphere of the rapidly oscillating star 33 Lib

NASA Astrophysics Data System (ADS)

Sachkov, M.; Hareter, M.; Ryabchikova, T.; Wade, G.; Kochukhov, O.; Shulyak, D.; Weiss, W. W.

2011-10-01

In 2009, the rapidly oscillating peculiar A-type (roAp) star 33 Lib was the target of an intense observing campaign, combining ground-based spectroscopy with space photometry obtained with the Microvariability and Oscillation of STars (MOST) satellite. We collected 780 spectra using the Echelle Spectro Polarimetric Device for the Observation of Stars (ESPaDOnS) spectrograph attached at the 3.6-m Canada-France-Hawaii Telescope and 374 spectra with the Fibre-fed Echelle Spectrograph attached at the 2.56-m Nordic Optical Telescope to perform time-resolved spectroscopy of 33 Lib. In addition, we used 111 Ultraviolet and Visual Echelle Spectrograph (UVES) spectra (2004) from the European Southern Observatory archive to check mode stability. Frequency analysis of the new radial velocity (RV) measurements confirms the previously reported frequency pattern (two frequencies and the first harmonic of the main one) and reveals an additional frequency at 1.991 mHz. The new frequency solution perfectly reproduces the RV variations from the 2004 and 2009 observational sets, providing strong support for p mode stability in this roAp star over at least 5 years.

SpecTracer: A Python-Based Interactive Solution for Echelle Spectra Reduction

NASA Astrophysics Data System (ADS)

Romero Matamala, Oscar Fernando; Petit, Véronique; Caballero-Nieves, Saida Maria

2018-01-01

SpecTracer is a newly developed interactive solution to reduce cross dispersed echelle spectra. The use of widgets saves the user the steep learning curves of currently available reduction software. SpecTracer uses well established image processing techniques based on IRAF to succesfully extract the stellar spectra. Comparisons with other reduction software, like IRAF, show comparable results, with the added advantages of ease of use, platform independence and portability. This tool can obtain meaningful scientific data and serve also as a training tool, especially for undergraduates doing research, in the procedure for spectroscopic analysis.

VizieR Online Data Catalog: Line list for red giants in open clusters (Reddy+, 2015)

NASA Astrophysics Data System (ADS)

Reddy, A. B. S.; Giridhar, S.; Lambert, D. L.

2017-11-01

Observations were carried out during observing runs in 2011 May and November, 2012 November and 2013 March using the Robert G. Tull echelle spectrograph (Tull et al. 1995PASP..107..251T) at the coude focus of the 2.7m Harlan J. Smith telescope located at the McDonald Observatory. On all occasions we employed a 2048x2048 24μm pixel, backside-illuminated, anti-reflection coated CCD as a detector and the 52.67 grooves/mm echelle grating with exposures centred at 5060Å. (2 data files).

Elemental abundance analyses with Complejo Astronomico EL Leoncito REOSC echelle spectrograms. III. HR 4487, 14 Hydrae, and 3 Centauri A

NASA Astrophysics Data System (ADS)

Pintado, O. I.; Adelman, S. J.; Gulliver, A. F.

1998-05-01

Using CASLEO echelle spectrograms, elemental abundances are derived for the sharp-lined non-magnetic CP stars HR 4487, 14 Hya, and 3 Cen A. The first two stars are members of the Mercury-Manganese subgroup and have abundances which are similar to other such peculiar stars. The third is a hotter related star. The detection of Mn II lines in its spectrum adds to this relationship. Table 3 is avaible electronically vit the CDS via anonymous ftp 130.79.128.5 or http://cdsweb.u-strasbg.fr/Abstract.html.

High resolution middle infrared spectrometer, a part of atmospheric chemistry suite (ACS) for EXOMARS 2016 trace gas orbiter

NASA Astrophysics Data System (ADS)

Trokhimovskiy, Alexander; Korablev, Oleg; Ivanov, Yurii; Syniavskyi, Ivan; Montmessin, Franck; Fedorova, Anna

2017-11-01

The Atmospheric Chemistry Suite (ACS) package is a part of Russian contribution to ExoMars ESARoscosmos mission for studies of the Martian atmosphere and climate. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. The mid-infrared (MIR) channel is a cross-dispersion high resolution echelle instrument dedicated to solar occultation measurements and sensitive studies of trace gases. The MIR channel is a spectrometer working in 2.3-4.2 μm spectral range, covering simultaneously up to almost 300 nm per exposure, targeting the resolving power of 50,000. A crossdispersion concept on echelle and ordinary diffraction grating allows acquisition of the wide wavelength domain at once. That provides a strategic advantage for maximizing the number of gaseous species detected simultaneously and good special resolution of measurements during fast occultation sessions. Moving the second grating allows to switch from one group of the diffraction orders to another prior to a series of measurements, or desired positions during one measurement sequence. The concept of the cross-dispersion echelle instrument, which is widely accepted in astronomy, has been already employed in planetary missions with VIRTIS-H instrument presently in flight on Rosetta and Venus Express missions. Targeting very high spectral resolution the MIR channel operates in solar occultation only. A telescope with relative aperture of 1∶3 forms the image of the solar disk on the slit. The FOV is determined by the slit and it consists 0.1×2.9 mrad. The spectral resolution of the spectrometer is fully slit-limited, and the resolving power of λ/Δλ >= 50000 at 3.3 μm is supported. Two secondary cross-dispersion diffraction gratings (plain, 180 and 361 grooves per mm) are mounted back-to-back on a stepper motor to change observed echelle orders. We have chosen two secondary gratings philosophy to switch between them depending on the long or short wavelength range we are on. Changing the position of the secondary grating in angular steps of 1.8°, from 10 to 30 echelle orders are available for simultaneous record depending on the wavelength. 100 steps are evidently used to switch between gratings prior measurements. The full spectral range is covered on diffraction orders from 142 to 248. For each observation detector area is covered by 10 to 30 stripes, each corresponding to single echelle diffraction order. Given the complexity of the diffraction orders pattern, full detector frames will be transmitted to the ground, with lossless compression. However, the onboard averaging will be possible. Single data frame will be accumulated for 0.5 seconds, stacking of a number of shorter exposures.

STS-111 Onboard Photo of the International Space Station

NASA Technical Reports Server (NTRS)

2002-01-01

Backdropped against the blackness of space is the International Space Station (ISS), as viewed from the approching Space Shuttle Orbiter Endeavour, STS-111 mission, in June 2002. Expedition Five replaced Expedition Four crew after remaining a record-setting 196 days in space. Three spacewalks enabled the STS-111 crew to accomplish the delivery and installation of the Mobile Remote Servicer Base System (MBS), an important part of the Station's Mobile Servicing System that allows the robotic arm to travel the length of the Station, which is necessary for future construction tasks; the replacement of a wrist roll joint on the Station's robotic arm, and the task of unloading supplies and science experiments from the Leonardo Multi-Purpose Logistics Module, which made its third trip to the orbital outpost. The STS-111 mission, the 14th Shuttle mission to visit the ISS, was launched on June 5, 2002 and landed June 19, 2002.

International Space Station (ISS)

NASA Image and Video Library

2002-06-07

Backdropped against the blackness of space is the International Space Station (ISS), as viewed from the approching Space Shuttle Orbiter Endeavour, STS-111 mission, in June 2002. Expedition Five replaced Expedition Four crew after remaining a record-setting 196 days in space. Three spacewalks enabled the STS-111 crew to accomplish the delivery and installation of the Mobile Remote Servicer Base System (MBS), an important part of the Station's Mobile Servicing System that allows the robotic arm to travel the length of the Station, which is necessary for future construction tasks; the replacement of a wrist roll joint on the Station's robotic arm, and the task of unloading supplies and science experiments from the Leonardo Multi-Purpose Logistics Module, which made its third trip to the orbital outpost. The STS-111 mission, the 14th Shuttle mission to visit the ISS, was launched on June 5, 2002 and landed June 19, 2002.

The third flight of the Colorado high-resolution echelle stellar spectrograph (CHESS): improvements, calibrations, and preliminary results

NASA Astrophysics Data System (ADS)

Kruczek, Nicholas; Nell, Nicholas; France, Kevin; Hoadley, Keri; Fleming, Brian; Kane, Robert; Ulrich, Stefan; Egan, Arika; Beatty, Dawson

2017-08-01

In this proceeding, we describe the scientific motivation and technical development of the Colorado HighResolution Echelle Stellar Spectrograph (CHESS), focusing on the hardware advancements and testing of components for the third launch of the payload (CHESS-3). CHESS is a far ultraviolet rocket-borne instrument designed to study the atomic-to-molecular transitions within translucent cloud regions in the interstellar medium. CHESS is an objective echelle spectrograph, which uses a mechanically-ruled echelle and a powered (f/12.4) crossdispersing grating, and is designed to achieve a resolving power R > 100,000 over the bandpass λλ 1000-1600 Å. Results from final efficiency and reflectivity measurements for the optical components of CHESS-3 are presented. An important role of sounding rocket experiments is the testing and verification of the space flight capabilities of experimental technologies. CHESS-3 utilizes a 40mm-diameter cross-strip anode microchannel plate detector fabricated by Sensor Sciences LLC, capable of achieving high spatial resolution and a high global count rate (˜1 MHz). We present pre-flight laboratory spectra and calibration results, including wavelength solution and resolving power of the instrument. The fourth launch of CHESS (CHESS-4) will demonstrate a δ-doped CCD, assembled in collaboration with the Microdevices Laboratory at JPL and Arizona State University. In support of CHESS-4, the CHESS-3 payload included a photomultiplier tube, used as a secondary confirmation of the optical alignment of the payload during flight. CHESS-3 launched on 26 June 2017 aboard NASA/CU sounding rocket mission 36.323 UG. We present initial flight results for the CHESS-3 observation of the β1 Scorpii sightline.

Fixed Delay Interferometry for Doppler Extrasolar Planet Detection

NASA Astrophysics Data System (ADS)

Ge, Jian

2002-06-01

We present a new technique based on fixed delay interferometry for high-throughput, high-precision, and multiobject Doppler radial velocity (RV) surveys for extrasolar planets. The Doppler measurements are conducted by monitoring the stellar fringe phase shifts of the interferometer instead of absorption-line centroid shifts as in state-of-the-art echelle spectroscopy. High Doppler sensitivity is achieved through optimizing the optical delay in the interferometer and reducing photon noise by measuring multiple fringes over a broad band. This broadband operation is performed by coupling the interferometer with a low- to medium-resolution postdisperser. The resulting fringing spectra over the bandpass are recorded on a two-dimensional detector, with fringes sampled in the slit spatial direction and the spectrum sampled in the dispersion direction. The resulting total Doppler sensitivity is, in theory, independent of the dispersing power of the postdisperser, which allows for the development of new-generation RV machines with much reduced size, high stability, and low cost compared to echelles. This technique has the potential to improve RV survey efficiency by 2-3 orders of magnitude over the cross-dispersed echelle spectroscopy approach, which would allow a full-sky RV survey of hundreds of thousands of stars for planets, brown dwarfs, and stellar companions once the instrument is operated as a multiobject instrument and is optimized for high throughput. The simple interferometer response potentially allows this technique to be operated at other wavelengths independent of popular iodine reference sources, being actively used in most of the current echelles for Doppler planet searches, to search for planets around early-type stars, white dwarfs, and M, L, and T dwarfs for the first time. The high throughput of this instrument could also allow investigation of extragalactic objects for RV variations at high precision.

Strategies facilitant les tests en pre-certification pour la robustesse a l'egard des radiations =

NASA Astrophysics Data System (ADS)

Souari, Anis

Les effets des radiations cosmiques sur l'electronique embarquee preoccupent depuis. quelques decennies les chercheurs interesses par la robustesse des circuits integres. Plusieurs. recherches ont ete menees dans cette direction, principalement pour les applications spatiales. ou l’environnement de leur deploiement est hostile. En effet, ces environnements sont denses. en termes de particules qui, lorsqu’elles interagissent avec les circuits integres, peuvent. mener a leur dysfonctionnement, voir meme a leur destruction. De plus, les effets des. radiations s’accentuent pour les nouvelles generations des circuits integres ou la diminution. de la taille des transistors et l’augmentation de la complexite de ces circuits augmentent la. probabilite d’apparition des anomalies et par consequence la croissance des besoins de test. L’expansion de l’electronique grand public (commercial off-the-shelf, COTS) et l’adoption. de ces composants pour des applications critiques comme les applications avioniques et. spatiales incitent egalement les chercheurs a doubler les efforts de verification de la fiabilite. de ces circuits. Les COTS, malgre leurs meilleures caracteristiques en comparaison avec les. circuits durcis tolerants aux radiations qui sont couteux et en retard en termes de technologie. utilisee, sont vulnerables aux radiations. Afin d’ameliorer la fiabilite de ces circuits, une evaluation de leur vulnerabilite dans les. differents niveaux d’abstraction du flot de conception est recommandee. Ceci aide les. concepteurs a prendre les mesures de mitigation necessaires sur le design au niveau. d’abstraction en question. Enfin, afin de satisfaire les exigences de tolerance aux pannes, des. tests tres couteux de certification, obtenus a l’aide de bombardement de particules (protons, neutrons, etc.), sont necessaires. Dans cette these, nous nous interessons principalement a definir une strategie de precertification. permettant d’evaluer d’une facon realiste la sensibilite des circuits integres face. aux effets des radiations afin d’eviter d’envoyer des circuits non robustes a la phase tres. couteuse de la certification. Les circuits cibles par nos travaux sont les circuits integres. programmables par l’usager (FPGA) a base de memoire SRAM et le type de pannes ciblees, causees par les radiations, est les SEU (single event upset) consistant a un basculement de. l’etat logique d’un element de memoire a son complementaire. En effet, les FPGA a base de. memoire SRAM sont de plus en plus demandes par la communaute de l’aerospatial grace a. leurs caracteristiques de prototypage rapide et de reconfiguration sur site mais ils sont. vulnerables face aux radiations ou les SEU sont les pannes les plus frequentes dans les. elements de memoire de type SRAM. Nous proposons une nouvelle approche d’injection de. pannes par emulation permettant de mimer les effets des radiations sur la memoire de. configuration des FPGA et de generer des resultats les plus fideles possibles des resultats des. tests de certification. Cette approche est basee sur la consideration de la difference de. sensibilite des elements de memoire de configuration lorsqu’ils sont a l’etat '1' et a l’etat '0', observee sous des tests acceleres sous faisceaux de protons au renomme laboratoire. TRIUMF, dans la procedure de generation des sequences de test dans le but de mimer la. distribution des pannes dans la memoire de configuration. Les resultats des experimentations. de validation montrent que la strategie proposee est efficace et genere des resultats realistes. Ces resultats revelent que ne pas considerer la difference de sensibilite peut mener a une. sous-estimation de la sensibilite des circuits face aux radiations. Dans la meme optique d’optimisation de la procedure d’injection des pannes par emulation, a. savoir le test de pre-certification, nous proposons une methodologie permettant de maximiser. la detection des bits critiques (bits provoquant une defaillance fonctionnelle s’ils changent. d’etat) pour un nombre bien determine de SEU (qui est le modele de pannes adopte) ou de. maximiser la precision de l’estimation de nombre des bits critiques. Pour ce faire, une. classification des bits de configuration en differents ensembles est tout d’abord mise en. oeuvre, selon leur contenu, les ressources qu’ils configurent et leur criticite. Ensuite, une. evaluation de la sensibilite de chaque ensemble est accomplie. Enfin, la priorisation. d’injection des pannes dans les ensembles les plus sensibles est recommandee. Plusieurs. scenarios d’optimisation d’injection des pannes sont proposes et les resultats sont compares. avec ceux donnes par la methode conventionnelle d’injection aleatoire des pannes. La. methodologie d’optimisation proposee assure une amelioration de plus de deux ordres de. grandeur. Une derniere approche facilitant l’evaluation de la sensibilite des bits configurant les LUT. (look up table) de FPGA, les plus petites entites configurables du FPGA permettant. d’implementer des fonctions combinatoires, utilises par un design est presentee. Elle permet. l’identification facile et sans cout en termes d’utilisation du materiel ou d’outils externes des. bits des LUT. L’approche proposee est simple et efficace, offrant une couverture de pannes. de 100 % et applicable aux nouvelles generations des FPGA de Xilinx. Les approches proposees contribuent a repondre aux exigences du cahier des charges de cette. these et a achever les objectifs definis. Le realisme et la maximisation de l’estimation de la. vulnerabilite des circuits sous test offerts par les nouvelles approches assurent le. developpement d’une strategie de test en pre-certification efficace. En effet, la premiere. approche d’injection de pannes considerant la difference de sensibilite relative des elements. de memoire selon leur contenu genere des resultats donnant une erreur relative atteignant. 3.1 % quand compares aux resultats obtenus a TRIUMF alors que l’erreur relative donnee. par la comparaison des resultats d’une injection conventionnelle aleatoire de pannes avec. ceux de TRIUMF peut atteindre la valeur de 75 %. De plus, l’application de cette approche a. des circuits plus conventionnels montre que 2.3 fois plus d’erreurs sont detectees en. comparaison avec l’injection aleatoire des pannes. Ceci suggere que ne pas considerer la. difference de sensibilite relative dans la procedure d’emulation peut mener a une sousestimation. de la sensibilite du design face aux radiations. Les resultats de la deuxieme. approche proposee ont ete aussi compares aux resultats d’une injection aleatoire de pannes. L’approche proposee, maximisant le nombre des bits critiques inverses, permet d’atteindre. un facteur d’acceleration de 108 de la procedure d’injection des pannes en comparaison a. l’approche aleatoire. Elle permet aussi de minimiser l’erreur d’estimation du nombre des bits. critiques pour atteindre une valeur de ±1.1 % calculee pour un intervalle de confiance de. 95 % tandis que la valeur d’erreur d’estimation des bits critiques generee par l’approche. aleatoire d’injection des pannes pour le meme intervalle de confiance peut atteindre ±8.6 %. Enfin, la derniere approche proposee d’injection de pannes dans les LUT se distingue des. autres approches disponibles dans la litterature par sa simplicite tout en assurant une. couverture maximale de pannes de 100 %. En effet, l’approche proposee est independante. des outils externes permettant d’identifier les bits configurant les LUT qui sont obsoletes ou. ne supportent pas les nouvelles generations des FPGA. Elle agit directement sur les fichiers. generes par l’outil de synthese adopte.

Alpha Centauri at a Crossroads

NASA Astrophysics Data System (ADS)

Ayres, Thomas

2015-10-01

Nearby Alpha Centauri AB (G2V+K1V) contains the two best characterized solar-like dwarf stars, which also have the best studied multi-MK coronal X-ray activity cycles, extending back to the 1970's. Objective is to continue tracking the evolving multi-decadal high-energy narrative of Alpha Cen with semiannual X-ray pointings in Chandra Cycles 16-18, as the system reaches a coronal crossroads: solar twin A rising toward starspot cycle maximum, K-type companion B sinking into a minimum. HST/STIS UV spectra will support and leverage the X-ray measurements by probing chromospheric and subcoronal dynamics, with connection to the corona through the FUV Fe XII 1242 forbidden line. Only Chandra can resolve the AB X-ray pair as the Alpha Cen orbit also reaches a crossroads in 2016 (only 4 separation), and only HST/STIS can measure the bright Alpha Cen stars with sufficient UV spectral resultion and wavelength coherence. What's more, the recent validation of the STIS NDA,B,C long slits for echelle use now make feasible NUV E230H measurements (e.g., of key chromospheric tracers Mg II 2800 and Mg I 2852) which heretofore were not practical in a long-term program of this nature.

Alpha Centauri at a Crossroads

NASA Astrophysics Data System (ADS)

Ayres, Thomas

2016-10-01

Nearby Alpha Centauri AB (G2V+K1V) contains the two best characterized solar-like dwarf stars, which also have the best studied multi-MK coronal X-ray activity cycles, extending back to the 1970's. Objective is to continue tracking the evolving multi-decadal high-energy narrative of Alpha Cen with semiannual X-ray pointings in Chandra Cycles 16-18, as the system reaches a coronal crossroads: solar twin A rising toward starspot cycle maximum, K-type companion B sinking into a minimum. HST/STIS UV spectra will support and leverage the X-ray measurements by probing chromospheric and subcoronal dynamics, with connection to the corona through the FUV Fe XII 1242 forbidden line. Only Chandra can resolve the AB X-ray pair as the Alpha Cen orbit also reaches a crossroads in 2016 (only 4 separation), and only HST/STIS can measure the bright Alpha Cen stars with sufficient UV spectral resolution and wavelength coherence. What's more, the recent validation of the STIS NDA,B,C long slits for echelle use now make feasible NUV E230H measurements (e.g., of key chromospheric tracers Mg II 2800 and Mg I 2852) which heretofore were not practical in a long-term program of this nature.

Fiber Mode Scrambler for the Subaru Infrared Doppler Instrument (IRD)

NASA Astrophysics Data System (ADS)

Ishizuka, Masato; Kotani, Takayuki; Nishikawa, Jun; Kurokawa, Takashi; Mori, Takahiro; Kokubo, Tsukasa; Tamura, Motohide

2018-06-01

We report the results of fiber mode scrambler experiments for the Infra-Red Doppler instrument (IRD) on the Subaru 8.2-m telescope. IRD is a fiber-fed, high precision radial velocity (RV) instrument to search for exoplanets around nearby M dwarfs at near-infrared wavelengths. It is a high-resolution spectrograph with an Echelle grating. The expected RV measurement precision is ∼1 m s‑1 with a state of the art laser frequency comb for the wavelength calibration. In IRD observations, one of the most significant instrumental noise is a change of intensity distribution of multi-mode fiber exit, which degrades RV measurement precision. To stabilize the intensity distribution of fiber exit an introduction of fiber mode scrambler is mandatory. Several kinds of mode scramblers have been suggested in previous research, though it is necessary to determine the most appropriate mode scrambler system for IRD. Thus, we conducted systematic measurements of performance for a variety of mode scramblers, both static and dynamic. We tested various length multi-mode fibers, an octagonal fiber, a double fiber scrambler, and two kinds of dynamic scramblers, and their combinations. We report the performances of these mode scramblers and propose candidate mode scrambler systems for IRD.

VizieR Online Data Catalog: Photmetry and spectroscopy of PMS stars in NGC 2264 (Lim+, 2016)

NASA Astrophysics Data System (ADS)

Lim, B.; Sung, H.; Kim, J. S.; Bessell, M. S.; Hwang, N.; Park, B.-G.

2018-04-01

Queue scheduled observations were carried out on 2015 April 1 and November 24 with the multi-object high resolution echelle spectrograph Hectochelle attached to the 6.5m telescope of the MMT observatory. The resolving power of the spectrograph (R~34,000) is high enough to detect the LiI λ6708 resonance doublet with little blending from adjacent metallic lines. The multi-object capability allowed us to simultaneously obtain 240 target and sky spectra in a single observation. The OB 26 filter transmits the wavelength range 6530-6715Å, and therefore the useful spectral features Hα λ6563 and HeI λ6678 could also be observed along with the LiI λ6708 line. The spectra of a total of 134 PMS stars were taken in two sets of exposure times -8 minutes x3 for bright stars (V<13.6mag) and 30 minutes x3 for fainter stars. Offset sky spectra were also obtained to correct for the contributions of locally variable nebula emission lines to the spectra of the faint stars. Calibration frames, such as dome flat and comparison spectra, were also acquired, just before and after the target exposure. (1 data file).

The Open Cluster Chemical Abundances and Mapping (OCCAM) Survey: Current Status

NASA Astrophysics Data System (ADS)

Frinchaboy, Peter; O'Connell, Julia; Donor, John; Cunha, Katia; Thompson, Benjamin; Melendez, Matthew; Shetrone, Matthew; Zasowski, Gail; Majewski, Steven R.; APOGEE TEAM

2018-01-01

The Open Cluster Chemical Analysis and Mapping (OCCAM) survey aims to produce a comprehensive, uniform, infrared-based data set forhundreds of open clusters, and constrain key Galactic dynamical and chemical parameters using the SDSS/APOGEE survey and follow-up from the McDonald Observatory Otto Struve 2.1-m telescope and Sandiford Cass Echelle Spectrograph (R ~ 60,000). We report on multi-element radial abundance gradients obtained from a sample of over 30 disk open clusters. The APOGEE chemical abundances were derived automatically by the ASPCAP pipeline and these are part of the SDSS IV Data Release 14, optical follow-up were analyzed using equivalent width analysis and spectral synthesis. We present the current open cluster sample that spans a significant range in age allowing exploration of the evolution of the Galactic abundance gradients. This work is supported by an NSF AAG grants AST-1311835 & AST-1715662.

Thirty Years, One Million Spectra: Public Access to the SAO Spectral Archives

NASA Astrophysics Data System (ADS)

Mink, J.; Moran, S.

2015-09-01

Over the last 30 years, the SAO Telescope Data Center has reduced and archived over 1,000,000 spectra, consisting of 287,000 spectra from five high dispersion Echelle spectrographs and 717,000 spectra from four low dispersion spectrographs, across three telescopes. 151,000 spectra from six instruments are currently online and publicly available, covering many interesting objects in the northern sky, including most of the galaxies in the Updated Zwicky Catalog which are reachable through NED or Simbad. A majority of the high dispersion spectra will soon be made public, as will more data from the MMT multi-fiber spectrographs. Many objects in the archive have multiple spectra over time, which make them a valuable resource for archival time-domain studies. We are now developing a system to make all of the public spectra more easily searchable and viewable through the Virtual Observatory.

Echelle Data Reduction Cookbook

NASA Astrophysics Data System (ADS)

Clayton, Martin

This document is the first version of the Starlink Echelle Data Reduction Cookbook. It contains scripts and procedures developed by regular or heavy users of the existing software packages. These scripts are generally of two types; templates which readers may be able to modify to suit their particular needs and utilities which carry out a particular common task and can probably be used `off-the-shelf'. In the nature of this subject the recipes given are quite strongly tied to the software packages, rather than being science-data led. The major part of this document is divided into two sections dealing with scripts to be used with IRAF and with Starlink software (SUN/1).

Performance of the CHIRON high-resolution Echelle spectrograph

NASA Astrophysics Data System (ADS)

Schwab, Christian; Spronck, Julien F. P.; Tokovinin, Andrei; Szymkowiak, Andrew; Giguere, Matthew; Fischer, Debra A.

2012-09-01

CHIRON is a fiber-fed Echelle spectrograph with observing modes for resolutions from 28,000 to 120,000, built primarily for measuring precise radial velocities (RVs). We present the instrument performance as determined during integration and commissioning. We discuss the PSF, the effect of glass inhomogeneity on the cross-dispersion prism, temperature stabilization, stability of the spectrum on the CCD, and detector characteristics. The RV precision is characterized, with an iodine cell or a ThAr lamp as the wavelength reference. Including all losses from the sky to the detector, the overall efficiency is about 6%; the dominant limitation is coupling losses into the fiber due to poor guiding.

Elemental abundance analyses with Complejo Astronomico. EL Leoncito REOSC echelle spectrograms. I. κ Cancri, HR 7245, and ξ Octantis

NASA Astrophysics Data System (ADS)

Pintado, O. I.; Adelman, S. J.

1996-08-01

Elemental abundances are derived for three sharp-lined stars κ Cnc, HR 7245, and ξ Oct using REOSC echelle spectrograms obtained at CASLEO. Comparisons are made with published equivalent widths. The derived abundances for κ Cnc and ξ Oct are slightly larger than those obtained with other high dispersion spectrographs. HR 7245 exhibits a pattern of abundance anomalies similar to other Mercury-Manganese stars. The spectra of the two HgMn stars in the λλ4640-5100 region exhibit an interesting and useful variety of lines which can be used to supplement analyses of the photographic region.

FIEStool: Automated data reduction for FIber-fed Echelle Spectrograph (FIES)

NASA Astrophysics Data System (ADS)

Stempels, Eric; Telting, John

2017-08-01

FIEStool automatically reduces data obtained with the FIber-fed Echelle Spectrograph (FIES) at the Nordic Optical Telescope, a high-resolution spectrograph available on a stand-by basis, while also allowing the basic properties of the reduction to be controlled in real time by the user. It provides a Graphical User Interface and offers bias subtraction, flat-fielding, scattered-light subtraction, and specialized reduction tasks from the external packages IRAF (ascl:9911.002) and NumArray. The core of FIEStool is instrument-independent; the software, written in Python, could with minor modifications also be used for automatic reduction of data from other instruments.

Photoelectrochemical fabrication of spectroscopic diffraction gratings, phase 2

NASA Technical Reports Server (NTRS)

Rauh, R. David; Carrabba, Michael M.; Li, Jianguo; Cartland, Robert F.; Hachey, John P.; Mathew, Sam

1990-01-01

This program was directed toward the production of Echelle diffraction gratings by a light-driven, electrochemical etching technique (photoelectrochemical etching). Etching is carried out in single crystal materials, and the differential rate of etching of the different crystallographic planes used to define the groove profiles. Etching of V-groove profiles was first discovered by us during the first phase of this project, which was initially conceived as a general exploration of photoelectrochemical etching techniques for grating fabrication. This highly controllable V-groove etching process was considered to be of high significance for producing low pitch Echelles, and provided the basis for a more extensive Phase 2 investigation.

Deep echelle spectrophotometry of S 311, a Galactic HII region located outside the solar circle

NASA Astrophysics Data System (ADS)

García-Rojas, J.; Esteban, C.; Peimbert, A.; Peimbert, M.; Rodríguez, M.; Ruiz, M. T.

2005-09-01

We present echelle spectrophotometry of the Galactic HII region S 311. The data have been taken with the Very Large Telescope Ultraviolet-Visual Echelle Spectrograph in the 3100-10400 Årange. We have measured the intensities of 263 emission lines; 178 are permitted lines of H0, D0 (deuterium), He0, C0, C+, N0, N+, O0, O+, S+, Si0, Si+, Ar0 and Fe0; some of them are produced by recombination and others mainly by fluorescence. Physical conditions have been derived using different continuum- and line-intensity ratios. We have derived He+, C++ and O++ ionic abundances from pure recombination lines as well as abundances from collisionally excited lines for a large number of ions of different elements. We have obtained consistent estimations of t2 applying different methods. We have found that the temperature fluctuations paradigm is consistent with the Te(HeI) versus Te(HI) relation for HII regions, in contrast with what has been found for planetary nebulae. We report the detection of deuterium Balmer lines up to Dδ in the blue wings of the hydrogen lines, whose excitation mechanism seems to be continuum fluorescence.

VizieR Online Data Catalog: Keck+Magellan survey for LLSs. III. (Prochaska+, 2015)

NASA Astrophysics Data System (ADS)

Prochaska, J. X.; O'Meara, J. M.; Fumagalli, M.; Bernstein, R. A.; Burles, S. M.

2016-01-01

The sample presented in this manuscript is intended to be a nearly all-inclusive set of Lyman Limit Systems (LLSs) discovered in the high-dispersion (echelle or echellette; R>5000) spectra that we have gathered at the Keck and Magellan telescopes. Regarding Keck, we have examined all of the data obtained by Principal Investigators (PIs) A. M. Wolfe and J. X. Prochaska at the W. M. Keck Observatory through 2012 April, and from PIs Burles, O'Meara, Bernstein, and Fumagalli at Magellan through 2012 July. We also include the Keck spectra analyzed by Penprase et al. (2010, J/ApJ/721/1). We present data obtained at the W. M. Keck and Las Campanas Observatories using the twin 10m Keck I and Keck II telescopes and the twin 6.5m Baade and Clay telescopes. Altogether, we used four spectrometers: (1) the High Resolution Echelle Spectrometer (HIRES); (2) the Echellette Spectrograph and Imager (ESI); (3) the Magellan Inamori Kyocera Echelle (MIKE); and (4) the Magellan Echellette Spectrograph (MagE). Observing logs for the HIRES and MIKE spectra are provided in Tables 1 and 2. (5 data files).

Spectrum of Th-Ar Hollow Cathode Lamps

National Institute of Standards and Technology Data Gateway

SRD 161 NIST Spectrum of Th-Ar Hollow Cathode Lamps (Web, free access)   This atlas presents observations of the infra-red (IR) spectrum of a low current Th-Ar hollow cathode lamp with the 2-m Fourier transform spectrometer (FTS) at NIST. These observations establish more than 2400 lines that are suitable for use as wavelength standards in the range 691 nm to 5804 nm. The observations were made in collaboration with the European Southern Observatory (ESO), in order to provide calibration reference data for new high-resolution Echelle spectrographs, such as the Cryogenic High-Resolution IR Echelle Spectrograph ([CRIRES]), ESO's new IR spectrograph at the Very Large Telescope in Chile.

Internal motions of HII regions and giant HII regions

NASA Technical Reports Server (NTRS)

Chu, You-Hua; Kennicutt, Robert C., Jr.

1994-01-01

We report new echelle observations of the kinematics of 30 HII regions in the Large Magellanic Clouds (LMC), including the 30 Doradus giant HII region. All of the HII regions possess supersonic velocity dispersions, which can be attributed to a combination of turbulent motions and discrete velocity splitting produced by stellar winds and/or embedded supernova remnants (SNRs). The core of 30 Dor is unique, with a complex velocity structure that parallels its chaotic optical morphology. We use our calibrated echelle data to measure the physical properties and energetic requirements of these velocity structures. The most spectacular structures in 30 Dor are several fast expanding shells, which appear to be produced at least partially by SNRs.

The assembly, calibration, and preliminary results from the Colorado high-resolution Echelle stellar spectrograph (CHESS)

NASA Astrophysics Data System (ADS)

Hoadley, Keri; France, Kevin; Nell, Nicholas; Kane, Robert; Schultz, Ted; Beasley, Matthew; Green, James; Kulow, Jen; Kersgaard, Eliot; Fleming, Brian

2014-07-01

The Colorado High-resolution Echelle Stellar Spectrograph (CHESS) is a far ultraviolet (FUV) rocket-borne experiment designed to study the atomic-to-molecular transitions within translucent interstellar clouds. CHESS is an objective echelle spectrograph operating at f/12.4 and resolving power of 120,000 over a band pass of 100 - 160 nm. The echelle flight grating is the product of a research and development project with LightSmyth Inc. and was coated at Goddard Space Flight Center (GSFC) with Al+LiF. It has an empirically-determined groove density of 71.67 grooves/mm. At the Center for Astrophysics and Space Astronomy (CASA) at the University of Colorado (CU), we measured the efficiencies of the peak and adjacent dispersion orders throughout the 90 - 165 nm band pass to characterize the behavior of the grating for pre-flight calibrations and to assess the scattered-light behavior. The crossdispersing grating, developed and ruled by Horiba Jobin-Yvon, is a holographically-ruled, low line density (351 grooves/mm), powered optic with a toroidal surface curvature. The CHESS cross-disperser was also coated at GSFC; Cr+Al+LiF was deposited to enhance far-UV efficiency. Results from final efficiency and reflectivity measurements of both optics are presented. We utilize a cross-strip anode microchannel plate (MCP) detector built by Sensor Sciences to achieve high resolution (25 μm spatial resolution) and data collection rates (~ 106 photons/second) over a large format (40mm round, digitized to 8k x 8k) for the first time in an astronomical sounding rocket flight. The CHESS instrument was successfully launched from White Sands Missile Range on 24 May 2014. We present pre-flight sensitivity, effective area calculations, lab spectra and calibration results, and touch on first results and post-flight calibration plans.

The science case of the PEPSI high-resolution echelle spectrograph and polarimeter for the LBT

NASA Astrophysics Data System (ADS)

Strassmeier, K. G.; Pallavicini, R.; Rice, J. B.; Andersen, M. I.

2004-05-01

We lay out the scientific rationale for and present the instrumental requirements of a high-resolution adaptive-optics Echelle spectrograph with two full-Stokes polarimeters for the Large Binocular Telescope (LBT) in Arizona. Magnetic processes just like those seen on the Sun and in the space environment of the Earth are now well recognized in many astrophysical areas. The application to other stars opened up a new field of research that became widely known as the solar-stellar connection. Late-type stars with convective envelopes are all affected by magnetic processes which give rise to a rich variety of phenomena on their surface and are largely responsible for the heating of their outer atmospheres. Magnetic fields are likely to play a crucial role in the accretion process of T-Tauri stars as well as in the acceleration and collimation of jet-like flows in young stellar objects (YSOs). Another area is the physics of active galactic nucleii (AGNs) , where the magnetic activity of the accreting black hole is now believed to be responsible for most of the behavior of these objects, including their X-ray spectrum, their notoriously dramatic variability, and the powerful relativistic jets they produce. Another is the physics of the central engines of cosmic gamma-ray bursts, the most powerful explosions in the universe, for which the extreme apparent energy release are explained through the collimation of the released energy by magnetic fields. Virtually all the physics of magnetic fields exploited in astrophysics is somehow linked to our understanding of the Sun's and the star's magnetic fields.

Precision stellar radial velocity measurements with FIDEOS at the ESO 1-m telescope of La Silla

NASA Astrophysics Data System (ADS)

Vanzi, L.; Zapata, A.; Flores, M.; Brahm, R.; Tala Pinto, M.; Rukdee, S.; Jones, M.; Ropert, S.; Shen, T.; Ramirez, S.; Suc, V.; Jordán, A.; Espinoza, N.

2018-07-01

We present results from the commissioning and early science programs of FIbre Dual Echelle Optical Spectrograph (FIDEOS), the new high-resolution echelle spectrograph developed at the Centre of Astro Engineering of Pontificia Universidad Catolica de Chile, and recently installed at the ESO 1-m telescope of La Silla. The instrument provides spectral resolution R ˜ 43 000 in the visible spectral range 420-800 nm, reaching a limiting magnitude of 11 in V band. Precision in the measurement of radial velocity is guaranteed by light feeding with an octagonal optical fibre, suitable mechanical isolation, thermal stabilization, and simultaneous wavelength calibration. Currently the instrument reaches radial velocity stability of ˜8 m s-1 over several consecutive nights of observation.

VizieR Online Data Catalog: Abundance ratio for 5 local stellar associations (Reddy+, 2015)

NASA Astrophysics Data System (ADS)

Reddy, A. B. S.; Lambert, D. L.

2018-01-01

In this paper, we have performed a homogeneous and a comprehensive abundance analysis using high-resolution spectroscopy. High-resolution and high signal-to-noise (S/N) spectra of the program stars were obtained during the nights of 2015 February 10-11 with the Robert G. Tull coude cross-dispersed echelle spectrograph (Tull et al. 1995PASP..107..251T) of the 2.7 m Harlan J. Smith reflector at the McDonald Observatory. We employed a Tektronix 2048x2048 24 μm pixel, backside illuminated and anti-reflection coated CCD as a detector and an R2 echelle grating with 52.67 grooves/mm with exposures centred at 5060 Å. (7 data files).

VizieR Online Data Catalog: MUSCLES Treasury Survey. IV. M dwarf UV fluxes (Youngblood+, 2017)

NASA Astrophysics Data System (ADS)

Youngblood, A.; France, K.; Loyd, R. O. P.; Brown, A.; Mason, J. P.; Schneider, P. C.; Tilley, M. A.; Berta-Thompson, Z. K.; Buccino, A.; Froning, C. S.; Hawley, S. L.; Linsky, J.; Mauas, P. J. D.; Redfield, S.; Kowalski, A.; Miguel, Y.; Newton, E. R.; Rugheimer, S.; Segura, A.; Roberge, A.; Vieytes, M.

2018-02-01

We selected stars with HST UV spectra and ground-based optical spectra either obtained directly by us or available in the VLT/XSHOOTER or Keck/HIRES public archives. Several targets have spectroscopic data obtained with the Dual Imaging Spectrograph (DIS) on the ARC 3.5m telescope at Apache Point Observatory (APO), R~2500, or the REOSC echelle spectrograph on the 2.15m telescope at Complejo Astronomico El Leoncito (CASLEO), R~12000, within a day or two of the HST observations. We also gathered spectra of GJ1132, GJ1214, and Proxima Cen on the nights of 2016 March 7-9 using the MIKE echelle spectrograph on the Magellan Clay telescope. (2 data files).

Design of FHiRE: the Fiber High Resolution Echelle Spectrograph

NASA Astrophysics Data System (ADS)

Pierce, Michael J.; McLane, Jacob N.; Pilachowski, C. A.; Kobulnicky, Henry; Jang-Condell, Hannah

2018-01-01

The enormous success of the Kepler mission in the discovery of transiting exoplanets implies that the majority of stars have planetary systems. NASA's upcomming Transiting Exoplanet Survey Satellite (TESS) is designed to survey the brightest stars over the entire sky, systems that are accessible to spectroscopic follow-up with mid-sized telescopes. We have undertaken the development of a precision radial velocity spectrograph with the goal of providing ground-based suppoert for TESS. The instrument, known as FHiRE (Fiber High Resolution Echelle spectrograph), is being developed in collaboration with Indiana University and will deployed at the 2.3-meter telescope of the Wyoming InfraRed Observatory (WIRO). FHiRE features a traditional white pupil echelle design with R ~ 60,000 that is fed via two optical fibers from the telescope. Both the science fiber and a simultaneously sampled Thorium-Argon comparison fiber will make use of double mode scramblers. FHiRE itself will be housed within a vacuum enclosure in order to minimize any temperatue variations of the instrument and maximize its radial velocity precision. Together, these two features should enable FHiRE to reach a long-term velocity precision of < 1 m/s. We present the design of FHiRE and its expected performance. In a companion poster (Jang-Condell et al.) we will present the exoplanet science goals of the project.

Minerva-Red: Small Planets Orbiting Small Stars

NASA Astrophysics Data System (ADS)

Blake, Cullen

2018-06-01

Recent results from Kepler and ground-based exoplanet surveys suggest that low-mass stars are host to numerous small planets. Since low-mass stars are intrinsically faint at optical wavelengths, obtaining the Doppler precision necessary to detect these companions remains a challenge for existing instruments. I will describe MINERVA-Red, a project to use a robotic, near-infrared optimized 0.7-meter telescope and a specialized Doppler spectrometer to carry out an intensive, multi-year campaign designed to reveal the planetary systems orbiting some of the closest stars to the Sun. The MINERVA-Red cross-dispersed echelle spectrograph is optimized for the “deep red”, between 800 nm and 900 nm, where the stars that will be targeted are relatively bright. The instrument is very compact and designed for the ultimate in Doppler precision – it uses a single-mode fiber input. I will describe the spectrometer and the status of the MINERVA-Red project, which is expected to begin routine operations at Whipple Observatory on Mt Hopkins, Arizona, in 2018.

VizieR Online Data Catalog: WOCS. LXXV. Hyades&Praesepe stellar lithium data (Cummings+, 2017)

NASA Astrophysics Data System (ADS)

Cummings, J. D.; Deliyannis, C. P.; Maderak, R. M.; Steinhauer, A.

2018-05-01

The Hyades and Praesepe open star clusters were both observed using the Hydra multi-object spectrograph on the WIYN 3.5-meter telescope using the 316@63.4 echelle grating in order 8 with the X19 filter. The spectra span from 6450 to 6850 Å. All Hyades stars and a majority of Praesepe stars were observed with blue cable, which yielded R~13600. The remaining Praesepe stars were observed with the red cable, which yielded a moderately higher R~17600. The Hyades data were acquired over seven nights from 2009 February 2 to 23. Using two red-cable configurations, we obtained spectra of 34 Praesepe candidate cluster members on 1997 November 16 and 18. Using seven blue cable configurations, we obtained spectra of 66 candidate cluster members during seven nights on 2001 December 2; 2005 May 1 and 2; 2006 January 25 and 26; and 2006 February 2 and 3. (2 data files).

MINERVA-Red: A Census of Planets Orbiting the Nearest Low-mass Stars to the Sun

NASA Astrophysics Data System (ADS)

Blake, Cullen; Johnson, John; Plavchan, Peter; Sliski, David; Wittenmyer, Robert A.; Eastman, Jason D.; Barnes, Stuart

2015-01-01

Recent results from Kepler and ground-based exoplanet surveys suggest that low-mass stars host numerous small planets. Since low-mass stars are intrinsically faint at optical wavelengths, obtaining the Doppler precision necessary to detect these companions remains a challenge for existing instruments. We describe MINERVA-Red, a project to use a dedicated, robotic, near-infrared optimized 0.7 meter telescope and a specialized Doppler spectrometer to carry out an intensive, multi-year campaign designed to reveal the planetary systems orbiting some of the closest stars to the Sun. The MINERVA-Red cross-dispersed echelle spectrograph is optimized for the 'deep red', between 800 nm and 900 nm, where these stars are relatively bright. The instrument is very compact and designed for the ultimate in Doppler precision by using single-mode fiber input. We describe the spectrometer and the status of the MINERVA-Red project, which is expected to begin routine operations at Whipple Observatory on Mt Hopkins, Arizona, in 2015.

VizieR Online Data Catalog: Solar-type stars from SDSS-III MARVELS. VI. HD 87646 (Ma+, 2016)

NASA Astrophysics Data System (ADS)

Ma, B.; Ge, J.; Wolszczan, A.; Muterspaugh, M. W.; Lee, B.; Henry, G. W.; Schneider, D. P.; Martin, E. L.; Niedzielski, A.; Xie, J.; Fleming, S. W.; Thomas, N.; Williamson, M.; Zhu, Z.; Agol, E.; Bizyaev, D.; da Costa, L. N.; Jiang, P.; Fiorenzano, A. F. M.; Hernandez, J. I. G.; Guo, P.; Grieves, N.; Li, R.; Liu, J.; Mahadevan, S.; Mazeh, T.; Nguyen, D. C.; Paegert, M.; Sithajan, S.; Stassun, K.; Thirupathi, S.; van Eyken, J. C.; Wan, X.; Wang, J.; Wisniewski, J. P.; Zhao, B.; Zucker, S.

2016-11-01

We have obtained a total of 16 observations of HD87646 using the W.M. Keck Exoplanet Tracker (KeckET) from 2006 December to 2007 June. The radial velocities obtained are listed in Table1. The KeckET instrument was constructed in 2005 August-2006 February with support from the Keck Foundation. It was coupled with a wide field Sloan Digital Sky Survey telescope (SDSS) and used for the pilot Multi-Object APO RV Exoplanet Large-Area Survey (MARVELS). This is the sixth paper in this series, examining the low-mass companions around solar-type stars from the SDSS-III MARVELS survey (Wisniewski et al. 2012, Cat. J/AJ/143/107; Fleming et al. 2012AJ....144...72F; Ma et al. 2013AJ....145...20M; Jiang et al. 2013AJ....146...65J; De Lee et al. 2013AJ....145..155D). The KeckET instrument consists of eight subsystems-a multi-object fiber feed, an iodine cell, a fixed-delay interferometer system, a slit, a collimator, a grating, a camera, and a 4k*4k CCD detector. In addition, it contains four auxiliary subsystems: the interferometer control, an instrument calibration system, a photon flux monitoring system, and a thermal probe and control system. The instrument is fed with 60 fibers with 200μm core diameters, which are coupled to 180μm core diameter short fibers from the SDSS telescope, corresponding to 3arcsec on the sky at f/5. The resolving power for the spectrograph is R=5100, and the wavelength coverage is ~900Å, centered at 5400Å. KeckET has one spectrograph and one 4k*4k CCD camera that captures one of the two interferometer outputs, and has a 5.5% detection efficiency from the telescope to the detector without the iodine cell under the typical APO seeing conditions (~1.5arcsec seeing). The CCD camera records fringing spectra from 59 objects in a single exposure. Subsequent observations were performed using the Exoplanet Tracker (ET) instrument at Kitt Peak National Observatory (KPNO). Initial follow-up was performed in 2007 November. Additional data points were obtained at KPNO in 2008 January, February, and May. The integration time was 35-40 minutes in 2007 November and 20 minutes in 2008 January, February, and May. A total of 40 data points were obtained from 2007 November to 2008 May and are also listed in Table1. Follow-up observations of HD87646 were conducted with the fiber-fed High Resolution Spectrograph (HRS) of the Hobby Eberley telescope (HET). The observations were executed in queue scheduled mode and used a 2 arcsec fiber, with the HRS slit set, to yield a spectral resolution of R~60000. A total of 29 data points were obtained between 2007 December and 2008 March. The HRS spectra consisted of 46 echelle orders recorded on the blue CCD (407-592nm) and 24 orders on the red one (602-784nm). The spectral data used for RV measurements were extracted from the 17 orders (505-592nm) in which the I2 cell superimposed strong absorption lines. The radial velocities obtained are also provided in Table1. HD87646 was selected as an radial velocity survey target by the Multi-object APO RV Exoplanet Large-area Survey (MARVELS) preselection criterion. The star has been monitored at 23 epochs using the MARVELS instrument mounted on the SDSS 2.5m Telescope at APO between 2009 May and 2011 December. The MARVELS instrument is a fiber-fed dispersed fixed-delay interferometer instrument capable of observing 60 objects simultaneously and covers a wavelength range of 5000-5700Å with a resolution of R~12000. The final differential radial velocity products are included in the SDSS Data Release 12 (Alam et al. 2015ApJS..219...12A) and are presented in Table1. We have obtained additional observations of HD87646 with a fiber-fed echelle spectrograph situated at the 2m Automatic Spectroscopic Telescope (AST) in the Fairborn Observatory. Through 2011 June, the detector was a 2048*4096 SITe ST-002A CCD with 15μm pixels. The AST echelle spectrograph has 21 orders that cover the wavelength range of 4920-7100Å, and has an average resolution of 0.17Å. In the summer of 2011, the SITe CCD detector and dewar were replaced with a Fairchild 486 CCD having 4K*4K 15μm pixels, which required a new readout electronics package, and a new dewar with a Cryotiger refrigeration system. The echelle spectrograms that were obtained with this new detector have 48 orders, covering the wavelength range of 3800-8260Å. A total of 135 data points were obtained from 2009 March through 2013 October and are listed in Table1. (1 data file).

Process analysis of recycled thermoplasts from consumer electronics by laser-induced plasma spectroscopy.

PubMed

Fink, Herbert; Panne, Ulrich; Niessner, Reinhard

2002-09-01

An experimental setup for direct elemental analysis of recycled thermoplasts from consumer electronics by laser-induced plasma spectroscopy (LIPS, or laser-induced breakdown spectroscopy, LIBS) was realized. The combination of a echelle spectrograph, featuring a high resolution with a broad spectral coverage, with multivariate methods, such as PLS, PCR, and variable subset selection via a genetic algorithm, resulted in considerable improvements in selectivity and sensitivity for this complex matrix. With a normalization to carbon as internal standard, the limits of detection were in the ppm range. A preliminary pattern recognition study points to the possibility of polymer recognition via the line-rich echelle spectra. Several experiments at an extruder within a recycling plant demonstrated successfully the capability of LIPS for different kinds of routine on-line process analysis.

AIRES: An Airborne Infra-Red Echelle Spectrometer for SOFIA

NASA Technical Reports Server (NTRS)

Dotson, Jessie J.; Erickson, Edwin F.; Haas, Michael R.; Colgan, Sean W. J.; Simpson, Janet P.; Telesco, Charles M.; Pina, Robert K.; Wolf, Juergen; Young, Erick T.

1999-01-01

SOFIA will enable astronomical observations with unprecedented angular resolution at infrared wavelengths obscured from the ground. To help open this new chapter in the exploration of the infrared universe, we are building AIRES, an Airborne Infra-Red Echelle Spectrometer. AIRES will be operated as a first generation, general purpose facility instrument by USRA, NASA's prime contractor for SOFIA. AIRES is a long slit spectrograph operating from 17 - 210 microns. In high resolution mode the spectral resolving power is approx. 10(exp 6) microns/A or approx. 10(exp 4) at 100 microns. Unfortunately, since the conference, a low resolution mode with resolving power about 100 times lower has been deleted due to budgetary constraints. AIRES includes a slit viewing camera which operates in broad bands at 18 and 25 microns.

VizieR Online Data Catalog: Detailed abundances of KOI stars with planets. I. (Schuler+, 2015)

NASA Astrophysics Data System (ADS)

Schuler, S. C.; Vaz, Z. A.; Katime Santrich, O. J.; Cunha, K.; Smith, V. V.; King, J. R.; Teske, J. K.; Ghezzi, L.; Howell, S. B.; Isaacson, H.

2016-03-01

We have analyzed high-resolution, high-signal-to-noise ratio (S/N) spectra of seven stars, each of which has at least one confirmed small planet discovered by Kepler. The spectra of these stars were obtained as part of the Kepler Follow-up Observing Program (KFOP). The 10m Keck I telescope and High Resolution Echelle Spectrometer (HIRES) are being utilized for precise RV measurements of high-priority KOIs. The KFOP spectra are characterized by a spectral resolution of R=50000 and span 3650-7950Å with incomplete coverage in the reddest orders. Additional observations of Kepler-21 were made independently with Keck/HIRES and the 4m Mayall telescope and echelle spectrograph at Kitt Peak National Observatory (KPNO) in UT 2011. (4 data files).

An echelle spectrograph for middle ultraviolet solar spectroscopy from rockets.

PubMed

Tousey, R; Purcell, J D; Garrett, D L

1967-03-01

An echelle grating spectrograph is ideal for use in a rocket when high resolution is required becaus itoccupies a minimum of space. The instrument described covers the range 4000-2000 A with a resolution of 0.03 A. It was designed to fit into the solar biaxial pointing-control section of an Aerobee-150 rocket. The characteristics of the spectrograph are illustrated with laboratory spectra of iron and carbon are sources and with solar spectra obtained during rocket flights in 1961 and 1964. Problems encountered in analyzing the spectra are discussed. The most difficult design problem was the elimination of stray light when used with the sun. Of the several methods investigated, the most effective was a predispersing system in the form of a zero-dispersion double monochromator. This was made compact by folding the beam four times.

VizieR Online Data Catalog: Abundance analysis of 9 very metal-poor stars (O'Malley+, 2017)

NASA Astrophysics Data System (ADS)

O'Malley, E. M.; McWilliam, A.; Chaboyer, B.; Thompson, I.

2017-10-01

We were awarded time on HST to obtain fine guidance sensor (FGS) parallaxes of nine very metal-poor stars with the goal of extending the range of metallicities below at least [Fe/H]=-2.3dex for stars with well-determined parallaxes. High-resolution spectroscopy of the nine target stars were obtained between 2008 and 2012 using the Magellan Inamori Kyocera Echelle (MIKE) double spectrograph on the 6.5m Magellan II Clay Telescope at Las Campanas Observatory, Chile (R=48000 for the red side and R=55000 for the blue side), and the High-Resolution Echelle Spectrometer (HiRES) on the twin telescopes at the W. M. Keck Observatory (R~70500). A log of the spectroscopic observations along with the HST F606W magnitudes and parallaxes appears in Table 1. (5 data files).

Optical design of a versatile FIRST high-resolution near-IR spectrograph

NASA Astrophysics Data System (ADS)

Zhao, Bo; Ge, Jian

2012-09-01

We report the update optical design of a versatile FIRST high resolution near IR spectrograph, which is called Florida IR Silicon immersion grating spectromeTer (FIRST). This spectrograph uses cross-dispersed echelle design with white pupils and also takes advantage of the image slicing to increase the spectra resolution, while maintaining the instrument throughput. It is an extremely high dispersion R1.4 (blazed angle of 54.74°) silicon immersion grating with a 49 mm diameter pupil is used as the main disperser at 1.4μm -1.8μm to produce R=72,000 while an R4 echelle with the same pupil diameter produces R=60,000 at 0.8μm -1.35μm. Two cryogenic Volume Phase Holographic (VPH) gratings are used as cross-dispersers to allow simultaneous wavelength coverage of 0.8μm -1.8μm. The butterfly mirrors and dichroic beamsplitters make a compact folding system to record these two wavelength bands with a 2kx2k H2RG array in a single exposure. By inserting a mirror before the grating disperser (the SIG and the echelle), this spectrograph becomes a very efficient integral field 3-D imaging spectrograph with R=2,000-4,000 at 0.8μm-1.8μm by coupling a 10x10 telescope fiber bundle with the spectrograph. Details about the optical design and performance are reported.

Current Calibration Efforts and Performance of the HST Space Telescope Imaging Spectrograph: Echelle Flux Calibration, the BAR5 Occulter, and Lamp Lifetimes

NASA Astrophysics Data System (ADS)

Monroe, TalaWanda R.; Aloisi, Alessandra; Debes, John H.; Jedrzejewski, Robert I.; Lockwood, Sean A.; Peeples, Molly S.; Proffitt, Charles R.; Riley, Allyssa; Walborn, Nolan R.

2016-06-01

The variety of operating modes of the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) continues to allow STIS users to obtain unique, high quality observations and cutting-edge results 19 years after its installation on HST. STIS is currently the only instrument available to the astronomy community that allows high spectral and spatial resolution spectroscopy in the FUV and NUV, including echelle modes. STIS also supports solar-blind imaging in the FUV. In the optical, STIS provides long-slit, first-order spectra that take advantage of HST's superb spatial resolution, as well as several unique unfiltered coronagraphic modes, which continue to benefit the exoplanet and debris-disk communities. The STIS instrument team monitors the instrument’s health and performance over time to characterize the effects of radiation damage and continued use of the detectors and optical elements. Additionally, the STIS team continues to improve the quality of data products for the user community. We present updates on efforts to improve the echelle flux calibration of overlapping spectral orders due to changes in the grating blaze function since HST Servicing Mission 4, and efforts to push the contrast limit and smallest inner working angle attainable with the coronagraphic BAR5 occulter. We also provide updates on the performance of the STIS calibration lamps, including work to maintain the accuracy of the wavelength calibration for all modes.

Precision measures of the primordial deuterium abundance.

NASA Astrophysics Data System (ADS)

Cooke, R. J.; Pettini, M.; Jorgenson, R. A.; Murphy, M. T.; Steidel, C. C.

Near-pristine damped Lyman-alpha systems (DLAs) are the ideal environments to measure the primordial abundance of deuterium. In this conference report, I summarise our ongoing research programme to obtain the most precise determination of the primordial deuterium abundance from five high redshift DLAs. From this sample, we derive (D/H)_p = (2.53±0.04)×105, corresponding to a baryon density 100 Omega_b ,0 h2 = 2.202±0.046 assuming the standard model of Big Bang Nucleosynthesis. This value is in striking agreement with that measured from the temperature fluctuations imprinted on the cosmic microwave background. Although we find no strong evidence for new physics beyond the standard model, this line of research shows great promise in the near-future, when the next generation 30+ m telescopes equipped with echelle spectrographs come online.

Relation of cyclic loading pattern to microstructural fracture in creep fatigue

NASA Technical Reports Server (NTRS)

Manson, S. S.; Halford, G. R.; Oldrieve, R. E.

1983-01-01

Creep-fatigue-environment interaction is discussed using the 'strainrange partitioning' (SRP) framework as a basis. The four generic SRP strainrange types are studied with a view of revealing differences in micromechanisms of deformation and fatigue degradation. Each combines in a different manner the degradation associated with slip-plane sliding, grain-boundary sliding, migration, cavitation, void development and environmental interaction; hence the approch is useful in delineating the relative importance of these mechanisms in the different loadings. Micromechanistic results are shown for a number of materials, including 316 SS, wrought heat resistant alloys, several nickel-base superalloys, and a tantalum base alloy, T-111. Although there is a commonality of basic behavior, the differences are useful in delineation several important principles of interpretation. Some quantitative results are presented for 316 SS, involving crack initiation and early crack growth, as well as the interaction of low-cycle fatigue with high-cycle fatigue.

The health promoting school and social justice in a global environment.

PubMed

Parsons, C

2004-01-01

Globalisation is present whether recognised in SARS, global terrorism, finance or youth music. With the growth of the health promoting school movement in this context and the increased numbers of countries and schools involved, eight themes are proposed as critical to how the Health Promotion School move forward. They are concerned with: the diverse origins and alliances of forces in the movement; holistic and ecological approach; its status as a global movement; the tension between and empowerment or compliances model; evidence-based and values-based approches; the radical vision; social capital and social inclusion; and sustainability. Reaching the level of acceptance the Health Promotion School has acheived may lead to settling into comfortable official recognition--and assured funding--and losing its militancy. Can the Health Promotion School challenge health inequalities on a national and international scale and can it be a force for social inclusion?

The robotized workstation "MASTER" for users with tetraplegia: description and evaluation.

PubMed

Busnel, M; Cammoun, R; Coulon-Lauture, F; Détriché, J M; Le Claire, G; Lesigne, B

1999-07-01

The rehabilitation robotics MASTER program was developed by the French Atomic Energy Commission (CEA) and evaluated by the APPROCHE Rehabilitation centers. The aim of this program is to increase the autonomy and quality of life of persons with tetraplegia in domestic and vocational environments. Taking advantage of its experience in nuclear robotics, the CEA has supported studies dealing with the use of such technical aids in the medical area since 1975 with the SPARTACUS project, followed by MASTER 10 years later, and its European extension in the framework of the TIDE/RAID program. The present system is composed of a fixed robotized workstation that includes a six-axis SCARA robot mounted on a rail to allow horizontal movement and is equipped with tools for various tasks. The Operator Interface (OI) has been carefully adapted to the most severe tetraplegia. Results are given following a 2-year evaluation in real-life situations.

Segunda discontinuidad de Balmer y procesos físicos en envolturas extendidas de estrellas Be

NASA Astrophysics Data System (ADS)

Bibbo, I.; Cruzado, A.; Ringuelet, A.

We study a group of Be stars in which the second Balmer jump is observed. Our aim is to correlate the second Balmer jump with other spectral features. Spectroscopic observations were performed with the 2.15 m telescope at Complejo Astronómico el Leoncito, CASLEO (San Juan, Argentina). In December 2001 and August 2002 high resolution echelle spectra were obtained with a REOSC echelle spectrograph. We find that, when a second Balmer jump in emission is observed, an emission in λ = 4233,17 Å of FeII multiplet 27 is also, generally seen. Besides, the electron temperature of the region of the envelope where the second jump is formed is estimated assuming that radiative recombinations cause the flux emission in the Balmer continuum. The temperature values obtained in this way are found correlated with the measure of the second Balmer jump.

Elemental abundance analyses with Complejo Astronomico El Leoncito REOSC echelle spectrograms. IV. Extensions of nine previous analyses

NASA Astrophysics Data System (ADS)

Adelman, S. J.; Pintado, O. I.

2000-02-01

Using new CASLEO echelle spectrograms, we extended our elemental abundances of the sharp-lined Mercury-Manganese stars mu Lep, 14 Hya, kappa Cnc, HR 4487, HR 4817, 28 Her, and HR 7245, the closely related star 3 Cen A, and 7 Sex an A0 V star with Population I abundances, but with Population II star space motions. The lambda lambda 4500-6200 region contains a sufficient number of lines to derive high-quality abundances of these stars. For most stars, the new spectra provide additional lines for the analyses which improve their quality as well as help fill in the periodic table. Table~5 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strabg.fr/Abstract.html}

VizieR Online Data Catalog: Radial velocities of HD 96511, HR 7578, and KZ And (Fekel+, 2017)

NASA Astrophysics Data System (ADS)

Fekel, F. C.; Henry, G. W.; Tomkin, J.

2018-06-01

Our new spectroscopic observations of HD 96511, HR 7578, and KZ And were obtained at three observatories. The majority were acquired from 2003 through 2017 with the Tennessee State University 2 m automatic spectroscopic telescope (AST) and a fiber-fed echelle spectrograph. That telescope is part of Fairborn Observatory near Washington Camp in the Patagonia Mountains of southeastern Arizona (Eaton & Williamson 2004SPIE.5496..710E, 2007PASP..119..886E). From 2005 through 2011 we acquired additional spectrograms at the Kitt Peak National Observatory (KPNO) with the coude feed telescope and coude spectrograph. Most of the observations were obtained with a Texas Instruments (TI) CCD detector. Finally, at McDonald Observatory in 2005 and 2006 we collected four spectra with the 2.1 m telescope, the Sandiford Cassegrain echelle spectrograph (McCarthy et al. 1993PASP..105..881M), and a Reticon CCD. (5 data files).

Immersion echelle spectrograph

DOEpatents

Stevens, Charles G.; Thomas, Norman L.

2000-01-01

A small spectrograph containing no moving components and capable of providing high resolution spectra of the mid-infrared region from 2 microns to 4 microns in wavelength. The resolving power of the spectrograph exceeds 20,000 throughout this region and at an optical throughput of about 10.sup.-5 cm.sup.2 sr. The spectrograph incorporates a silicon immersion echelle grating operating in high spectral order combined with a first order transmission grating in a cross-dispersing configuration to provide a two-dimensional (2-D) spectral format that is focused onto a two-dimensional infrared detector array. The spectrometer incorporates a common collimating and condensing lens assembly in a near aberration-free axially symmetric design. The spectrometer has wide use potential in addition to general research, such as monitoring atmospheric constituents for air quality, climate change, global warming, as well as monitoring exhaust fumes for smog sources or exhaust plumes for evidence of illicit drug manufacture.

Performance of a laser frequency comb calibration system with a high-resolution solar echelle spectrograph

NASA Astrophysics Data System (ADS)

Doerr, H.-P.; Kentischer, T. J.; Steinmetz, T.; Probst, R. A.; Franz, M.; Holzwarth, R.; Udem, Th.; Hänsch, T. W.; Schmidt, W.

2012-09-01

Laser frequency combs (LFC) provide a direct link between the radio frequency (RF) and the optical frequency regime. The comb-like spectrum of an LFC is formed by exact equidistant laser modes, whose absolute optical frequencies are controlled by RF-references such as atomic clocks or GPS receivers. While nowadays LFCs are routinely used in metrological and spectroscopic fields, their application in astronomy was delayed until recently when systems became available with a mode spacing and wavelength coverage suitable for calibration of astronomical spectrographs. We developed a LFC based calibration system for the high-resolution echelle spectrograph at the German Vacuum Tower Telescope (VTT), located at the Teide observatory, Tenerife, Canary Islands. To characterize the calibration performance of the instrument, we use an all-fiber setup where sunlight and calibration light are fed to the spectrograph by the same single-mode fiber, eliminating systematic effects related to variable grating illumination.

PEPSI spectro-polarimeter for the LBT

NASA Astrophysics Data System (ADS)

Strassmeier, Klaus G.; Hofmann, Axel; Woche, Manfred F.; Rice, John B.; Keller, Christoph U.; Piskunov, N. E.; Pallavicini, Roberto

2003-02-01

PEPSI (Postham Echelle Polarimetric and Spectroscopic Instrument) is to use the unique feature of the LBT and its powerful double mirror configuration to provide high and extremely high spectral resolution full-Stokes four-vector spectra in the wavelength range 450-1100nm. For the given aperture of 8.4m in single mirror mode and 11.8m in double mirror mode, and at a spectral resolution of 40,000-300,000 as designed for the fiber-fed Echelle spectrograph, a polarimetric accuracy between 10-4 and 10-2 can be reached for targets with visual magnitudes of up to 17th magnitude. A polarimetric accuracy better than 10-4 can only be reached for either targets brighter than approximately 10th magnitude together wiht a substantial trade-off wiht the spectral resolution or with spectrum deconvolution techniques. At 10-2, however, we will be able to observe the brightest AGNs down to 17th magnitude.

VizieR Online Data Catalog: Abundances of bright metal-poor stars (Schlaufman+, 2014)

NASA Astrophysics Data System (ADS)

Schlaufman, K. C.; Casey, A. R.

2016-11-01

As input to our sample selection, we use the APASS DR6 Catalog, the 2MASS All-Sky Point Source Catalog, and the AllWISE Source Catalog (Henden+ 2012JAVSO..40..430H; Skrutskie+ 2006AJ....131.1163S; Wright+ 2010AJ....140.1868W; Mainzer+ 2011ApJ...731...53M). We followed up our metal-poor star candidates with the Mayall 4m/Echelle, Gemini South/GMOS-S, and Magellan/MIKE telescopes and spectrographs. We observed 98 stars with the Mayall 4m/Echelle on 2013 June 25-27. We observed 90 stars with Gemini South/GMOS-S in service mode from 2014 March to July (R~3700). We observed 416 stars with Magellan/MIKE on 2014 June 21-23 and July 8-10 (R~41000 in the blue and R~35000 in the red). (3 data files).

The high-resolution cross-dispersed echelle white-pupil spectrometer of the McDonald Observatory 2.7-m telescope

NASA Technical Reports Server (NTRS)

Tull, Robert G.; Macqueen, Phillip J.; Sneden, Christopher; Lambert, David L.

1995-01-01

A new high-resolution cross-dispersed echelle spectrometer has been installed at the coude focus of the McDonald Observatory 2.7-m telescope. Its primary goal was simultaneously to gather spectra over as much of the spectral range 3400 A to 1 micrometer as practical, at a resolution R identical with lambda/Delta lambda which approximately = 60,000 with signal-to-noise ratio of approximately 100 for stars down to magnitude 11, using 1-h exposures. In the instrument as built, two exposures are all that are needed to cover the full range. Featuring a white-pupil design, fused silica prism cross disperser, and folded Schmidt camera with a Tektronix 2048x2048 CCD used at either of two foci, it has been in regularly scheduled operation since 1992 April. Design details and performance are described.

Spectroscopical Study of Faint Southern Cepheids with Southern African Large Telescope (salt). First Results.

NASA Astrophysics Data System (ADS)

Usenko, I. A.; Kniazev, A. Yu.; Kovtyukh, V. V.; Belik, S. I.; Berdnikov, L. N.

First Cepheids observations using echelle-spectrograph HRS fed by Southern African Large Telescope (SALT) were realized during 2016. All spectra have been obtained in the medium resoltion mode (R≍ 31000-41000) wth high S/N ratio near 50-220. All data were processed using package developed by authors based on the standard system of astronomical data reduction MIDAS. Using new echelle data we found the atmosphere parameters and chemical composition for 30 faint Cepheids of southern hemisphere, where for the most of theses stars these results we obtained for the first time. 28 stars are Cepheids after the first-dredge up stage, while ASAS 075842-25336.1 and ASAS 1131714-6605.0 having remarkable Li I 6707.8 Å absorption line and anomalous CNO and Na content could be consider as first crossing of the Cepheids instability strip.

Effet de la composition des materiaux composites sur la caracterisation et detection par ondes de Lamb

NASA Astrophysics Data System (ADS)

Ostiguy, Pierre-Claude

Les matériaux composites sont de plus en plus utilisés en aéronautique. Leurs excellentes propriétés mécaniques et leur faible poids leur procurent un avantage certain par rapport aux matériaux métalliques. Ceux-ci étant soumis à diverses conditions de chargement et environnementales, ils sont suceptibles de subir plusieurs types d'endommagements, compromettant leur intégrité. Des méthodes fiables d'inspection sont donc nécessaires pour évaluer leur intégrité. Néanmoins, peu d'approches non destructives, embarquées et efficaces sont présentement utilisées. Ce travail de recherche se penche sur l'étude de l'effet de la composition des matériaux composites sur la détection et la caractérisation par ondes guidées. L'objectif du projet est de développer une approche de caractérisation mécanique embarquée permettant d'améliorer la performance d'une approche d'imagerie par antenne piézoélectriques sur des structures composite et métalliques. La contribution de ce projet est de proposer une approche embarquée de caractérisation mécanique par ultrasons qui ne requiert pas une mesure sur une multitude d'échantillons et qui est non destructive. Ce mémoire par articles est divisé en quatre parties, dont les parties deux A quatre présentant les articles publiés et soumis. La première partie présente l'état des connaissances dans la matière nécessaires à l'acomplissement de ce projet de maîtrise. Les principaux sujets traités portent sur les matériaux composites, propagation d'ondes, la modélisation des ondes guidées, la caractérisation par ondes guidées et la surveillance embarquée des structures. La deuxième partie présente une étude de l'effet des propriétés mécaniques sur la performance de l'algorithme d'imagerie Excitelet. L'étude est faite sur une structure isotrope. Les résultats ont démontré que l'algorithme est sensible à l'exactitude des propriétés mécaniques utilisées dans le modèle. Cette sensibilité a également été explorée afin de développer une méthode embarquée permettant d'évaluer les propriétés mécaniques d'une structure. La troisième partie porte sur une étude plus rigoureuse des performances de la méthode de caractérisation mécanique embarquée. La précision, la répétabilité et la robustesse de la méthode sont validés à l'aide d'un simulateur par FEM. Les propriétés estimées avec l'approche de caractérisation sont à moins de 1% des propriétés utilisées dans le modèle, ce qui rivalise avec l'incertitude des méthodes ASTM. L'analyse expérimentale s'est avérée précise et répétable pour des fréquences sous les 200 kHz, permettant d'estimer les propriétés mécaniques à moins de 1% des propriétés du fournisseur. La quatrième partie a démontrée la capacité de l'approche de caractérisation à identifier les propriétés mécaniques d'une plaques composite orthotrope. Les résultats estimés expérimentalement sont inclus dans les barres d'incertitude des propriétés estimées à l'aide des tests ASTM. Finalement, une simulation FEM a démontré la précision de l'approche avec des propriétés mécaniques à moins de 4 % des propriétés du modèle simulé. Mots-clés : Inspection non destructive, composites, caractérisation mécanique, ultrasons, imagerie, SHM, ondes guidées.

Pour une approche des grammaires d'apprentissage (Toward an Approach to Learners' Grammars).

ERIC Educational Resources Information Center

Feve, Guy

1984-01-01

An approach to teaching grammar that combines an understanding of the error patterns of nonnative speakers and a theoretical model that describes that language is better suited than most to the actual audience of that instruction. (MSE)

VizieR Online Data Catalog: IRAS 22023+5249 spectroscopy (Sarkar+, 2012)

NASA Astrophysics Data System (ADS)

Sarkar, G.; Garcia-Hernandez, D. A.; Parthasarathy, M.; Manchado, A.; Garcia-Lario, P.; Takeda, Y.

2012-10-01

IRAS 22023+5249 was observed on 14 July 2001 using the Utrecht Echelle Spectrograph on the 4.2m William Herschel Telescope at the Roque de los Muchachos Observatory in La Palma (Spain). (3 data files).

The Owl and other strigiform nebulae: multipolar cavities within a filled shell

NASA Astrophysics Data System (ADS)

García-Díaz, Ma T.; Steffen, W.; Henney, W. J.; López, J. A.; García-López, F.; González-Buitrago, D.; Áviles, A.

2018-06-01

We present the results of long-slit echelle spectroscopy and deep narrow-band imaging of the Owl Nebula (NGC 3587), obtained at the Observatorio Astronómico Nacional, San Pedro Mártir. These data allow us to construct an iso-velocity data cube and develop a 3-D morpho-kinematic model. We find that, instead of the previously assumed bipolar dumbbell shape, the inner cavity consists of multi-polar fingers within an overall tripolar structure. We identify three additional planetary nebulae that show very similar morphologies and kinematics to the Owl, and propose that these constitute a new class of strigiform (owl-like) nebulae. Common characteristics of the strigiform nebulae include a double-shell (thin outside thick) structure, low-luminosity and high-gravity central stars, the absence of a present-day stellar wind, and asymmetric inner cavities, visible in both optical and mid-infrared emission lines, that show no evidence for surrounding bright rims. The origin of the cavities is unclear, but they may constitute relics of an earlier stage of evolution when the stellar wind was active.

Multi-object medium resolution optical spectroscopy at the E-ELT

NASA Astrophysics Data System (ADS)

Spanò, Paolo; Bonifacio, Piercarlo

2008-07-01

We present the design of a compact medium resolution spectrograph (R~15,000-20,000), intended to operate on a 42m telescope in seeing-limited mode. Our design takes full advantage of some new technology optical components, like volume phase holographic (VPH) gratings. At variance with the choice of complex large echelle spectrographs, which have been the standard on 8m class telescopes, we selected an efficient VPH spectrograph with a limited beam diameter, in order to keep overall dimensions and costs low, using proven available technologies. To obtain such a resolution, we need to moderately slice the telescope image plane onto the spectrograph entrance slit (5-6 slices). Then, standard telescope AO-mode (GLAO, Ground Layer Adaptive Optics) can be used over a large field of view (~10 arcmin), without loosing efficiency. Multiplex capabilities can greatly increase the observing efficiency. A robotic pick-up mirror system can be implemented, within conventional environmental conditions (temperature, pressure, gravity, size), demanding only standard mechanical and optical tolerances. A modular approach allows us scaling multiplex capabilities on overall costs and available space.

Caracterisation pratique des systemes quantiques et memoires quantiques auto-correctrices 2D

NASA Astrophysics Data System (ADS)

Landon-Cardinal, Olivier

Cette these s'attaque a deux problemes majeurs de l'information quantique: - Comment caracteriser efficacement un systeme quantique? - Comment stocker de l'information quantique? Elle se divise done en deux parties distinctes reliees par des elements techniques communs. Chacune est toutefois d'un interet propre et se suffit a elle-meme. Caracterisation pratique des systemes quantiques. Le calcul quantique exige un tres grand controle des systemes quantiques composes de plusieurs particules, par exemple des atomes confines dans un piege electromagnetique ou des electrons dans un dispositif semi-conducteur. Caracteriser un tel systeme quantique consiste a obtenir de l'information sur l'etat grace a des mesures experimentales. Or, chaque mesure sur le systeme quantique le perturbe et doit done etre effectuee apres avoir reprepare le systeme de facon identique. L'information recherchee est ensuite reconstruite numeriquement a partir de l'ensemble des donnees experimentales. Les experiences effectuees jusqu'a present visaient a reconstruire l'etat quantique complet du systeme, en particulier pour demontrer la capacite de preparer des etats intriques, dans lesquels les particules presentent des correlations non-locales. Or, la procedure de tomographie utilisee actuellement n'est envisageable que pour des systemes composes d'un petit nombre de particules. Il est donc urgent de trouver des methodes de caracterisation pour les systemes de grande taille. Dans cette these, nous proposons deux approches theoriques plus ciblees afin de caracteriser un systeme quantique en n'utilisant qu'un effort experimental et numerique raisonnable. - La premiere consiste a estimer la distance entre l'etat realise en laboratoire et l'etat cible que l'experimentateur voulait preparer. Nous presentons un protocole, dit de certification, demandant moins de ressources que la tomographie et tres efficace pour plusieurs classes d'etats importantes pour l'informatique quantique. - La seconde approche, dite de tomographie variationnelle, propose de reconstruire l'etat en restreignant l'espace de recherche a une classe variationnelle plutot qu'a l'immense espace des etats possibles. Un etat variationnel etant decrit par un petit nombre de parametres, un petit nombre d'experiences peut suffire a identifier les parametres variationnels de l'etat experimental. Nous montrons que c'est le cas pour deux classes variationnelles tres utilisees, les etats a produits matriciels (MPS) et l'ansatz pour intrication multi-echelle (MERA). Memoires quantiques auto-correctrices 2D. Une memoire quantique auto-correctrice est un systeme physique preservant de l'information quantique durant une duree de temps macroscopique. Il serait done l'equivalent quantique d'un disque dur ou d'une memoire flash equipant les ordinateurs actuels. Disposer d'un tel dispositif serait d'un grand interet pour l'informatique quantique. Une memoire quantique auto-correctrice est initialisee en preparant un etat fondamental, c'est-a-dire un etat stationnaire de plus basse energie. Afin de stocker de l'information quantique, il faut plusieurs etats fondamentaux distincts, chacun correspondant a une valeur differente de la memoire. Plus precisement, l'espace fondamental doit etre degenere. Dans cette these, on s'interesse a des systemes de particules disposees sur un reseau bidimensionnel (2D), telles les pieces sur un echiquier, qui sont plus faciles a realiser que les systemes 3D. Nous identifions deux criteres pour l'auto-correction: - La memoire quantique doit etre stable face aux perturbations provenant de l'environnement, par exemple l'application d'un champ magnetique externe. Ceci nous amene a considerer les systemes topologiques 2D dont les degres de liberte sont intrinsequement robustes aux perturbations locales de l'environnement. - La memoire quantique doit etre robuste face a un environnement thermique. Il faut s'assurer que les excitations thermiques n'amenent pas deux etats fondamentaux distincts vers le meme etat excite, sinon l'information aura ete perdue. Notre resultat principal montre qu'aucun systeme topologique 2D n'est auto-correcteur: l'environnement peut changer l'etat fondamental en deplacant aleatoirement de petits paquets d'energie, un mecanisme coherent avec l'intuition que tout systeme topologique admet des excitations localisees ou quasiparticules. L'interet de ce resultat est double. D'une part, il oriente la recherche d'un systeme auto-correcteur en montrant qu'il doit soit (i) etre tridimensionnel, ce qui est difficile a realiser experimentalement, soit (ii) etre base sur des mecanismes de protection nouveaux, allant au-dela des considerations energetiques. D'autre part, ce resultat constitue un premier pas vers la demonstration formelle de l'existence de quasiparticules pour tout systeme topologique.

The formation and evolution of high-redshift dusty galaxies

NASA Astrophysics Data System (ADS)

Ma, Jingzhe; Gonzalez, Anthony H.; Ge, Jian; Vieira, Joaquin D.; Prochaska, Jason X.; Spilker, Justin; Strandet, Maria; Ashby, Matthew; Noterdaeme, Pasquier; Lundgren, Britt; Zhao, Yinan; Ji, Tuo; Zhang, Shaohua; Caucal, Paul; SPT SMG Collaboration

2017-01-01

Star formation and chemical evolution are among the biggest questions in galaxy formation and evolution. High-redshift dusty galaxies are the best sites to investigate mass assembly and growth, star formation rates, star formation history, chemical enrichment, and physical conditions. My thesis is based on two populations of high-redshift dusty galaxies, submillimeter galaxies (SMGs) and quasar 2175 Å dust absorbers, which are selected by dust emission and dust absorption, respectively.For the SMG sample, I have worked on the gravitationally lensed dusty, star-forming galaxies (DSFGs) at 2.8 < z < 5.7, which were first discovered by the South Pole Telescope (SPT) and further confirmed by ALMA. My thesis is focused on the stellar masses and star formation rates of these objects by means of multi-wavelength spectral energy distribution (SED) modelling. The data include HST/WFC3, Spitzer/IRAC, Herschel/PACS, Herschel/SPIRE, APEX/Laboca and SPT. Compared to the star-forming main sequence (MS), these DSFGs have specific SFRs that lie above the MS, suggesting that we are witnessing ongoing strong starburst events that may be driven by major mergers. SPT0346-52 at z = 5.7, the most extraordinary source in the SPT survey for which we obtained Chandra X-ray and ATCA radio data, was confirmed to have the highest star formation surface density of any known galaxy at high-z.The other half of my thesis is focused on a new population of quasar absorption line systems, 2175 Å dust absorbers, which are excellent probes of gas and dust properties, chemical evolution and physical conditions in the absorbing galaxies. This sample was selected from the SDSS and BOSS surveys and followed up with the Echelle Spectrographs and Imager on the Keck-II telescope, the Red & Blue Channel Spectrograph on the Multiple Mirror Telescope, and the Ultraviolet and Visible Echelle Spectrograph onboard the Very Large Telescope. We found a correlation between the presence of the 2175 Å bump and other ingredients including high metallicity, high depletion level, overall low ionization state of gas, neutral carbon and molecules. I have also pushed forward this study by using HST IR grism to link the absorber and the host galaxy.

ARC-2009-ACD09-0108-001

NASA Image and Video Library

2009-02-08

An SUV-sized Asteroid 2008TC# Impacts on October 7, 2008 in the Nubian Desert, Northern Sudan: Dr. Peter Jenniskens, NASA/SETI joined Muawia Shaddas of the University of Khartoum in leading an expedition on a search for samples. (approch station 6) Photo Credit: NASA/SETI/P. Jenniskens

Evaluation d'un ecosysteme pastoral sahelien: Apport de la geomatique (Oursi, Burkina Faso)

NASA Astrophysics Data System (ADS)

Kabore, Seraphine Sawadogo

L'objectif principal de cette recherche est la mise au point d'une architecture d'integration de donnees socio-bio-geographiques et de donnees satellitales dans un Systeme d'Information Geographique (SIG) en vue d'une aide a la prise de decisions dans un environnement semi-aride au nord du Burkina Faso. Elle repond a la question fondamentale de l'interpretation des effets des facteurs climatiques et socioeconomiques sur le milieu pastoral. La recherche s'est appuyee sur plusieurs hypotheses de travail: possibilite d'utilisation de modele de simulation, d'approche multicritere et de donnees de teledetection dans un cadre de systeme d'information geographique. L'evolution spatiotemporelle des parametres de productivite du milieu a ete evaluee par approche dynamique selon le modele de Wu et al. (1996) qui modelise les interactions entre le climat, le milieu physique, le vegetal et l'animal pour mieux quantifier la biomasse primaire. A ce modele, quatre parametres ont ete integres par approche floue et multicritere afin de prendre en compte la dimension socioeconomique de la productivite pastorale (apport majeur de la recherche): la sante, l'education, l'agriculture et l'eau. La teledetection (imagerie SPOT) a permis de definir la production primaire a partir de laquelle les simulations ont ete realisees sur 10 annees. Les resultats obtenus montrent une bonne correlation entre biomasse primaire in situ et celle calculee pour les deux modeles, avec toutefois une meilleure efficacite du modele modifie (4 fois plus) dans les zones de forte productivite ou l'on note un taux de surexploitation agricole eleve. A cause de la variabilite spatiale de la production primaire in situ, les erreurs des resultats de simulation (8 a 11%) sont acceptables et montrent la pertinence de l'approche grace a l'utilisation des SIG pour la spatialisation et l'integration des differents parametres des modeles. Les types de production secondaire preconises (production de lait pendant 7 mois ou de viande pendant 6 mois) sont bases sur les besoins de l'UBT et le disponible fourrager qui est de qualite mediocre en saison seche. Dans les deux cas de figure, un deficit fourrager est observe. Deux types de transhumance sont proposes afin d'assurer une production durable selon deux scenarios: exploitation rationnelle des unites pastorales selon un plan de rotation annuelle et mise en defens a moyen terme des zones degradees pour une regeneration. Les zones potentielles pour la transhumance ont ete determinees selon les limites acceptables des criteres d'exploitation durable des milieux saheliens definis par Kessler (1994) soit 0,2 UBT.ha-1.

Synthese de champs sonores adaptative

NASA Astrophysics Data System (ADS)

Gauthier, Philippe-Aubert

La reproduction de champs acoustiques est une approche physique au probleme technologique de la spatialisation sonore. Cette these concerne l'aspect physique de la reproduction de champs acoustiques. L'objectif principal est l'amelioration de la reproduction de champs acoustiques par "synthese de champs acoustiques" ("Wave Field Synthesis", WFS), une approche connue, basee sur des hypotheses de champ libre, a l'aide du controle actif par l'ajout de capteurs de l'erreur de reproduction et d'une boucle fermee. Un premier chapitre technique (chapitre 4) expose les resultats d'appreciation objective de la WFS par simulations et mesures experimentales. L'effet indesirable de la salle de reproduction sur les qualites objectives de la WFS fut illustre. Une premiere question de recherche fut ensuite abordee (chapitre 5), a savoir s'il est possible de reproduire des champs progressifs en salle dans un paradigme physique de controle actif: cette possibilite fut prouvee. L'approche technique privilegiee, "synthese de champs adaptative" ("Adaptive Wave Field Synthesis" [AWFS]), fut definie, puis simulee (chapitre 6). Cette approche d'AWFS comporte une originalite en controle actif et en reproduction de champs acoustiques: la fonction cout quadratique representant la minimisation des erreurs de reproduction inclut une regularisation de Tikhonov avec solution a priori qui vient de la WFS. L'etude de l'AWFS a l'aide de la decomposition en valeurs singulieres (chapitre 7) a permis de comprendre les mecanismes propres a l'AWFS. C'est la deuxieme principale originalite de la these. L'algorithme FXLMS (LMS et reference filtree) est modifie pour l'AWFS (chapitre 8). Le decouplage du systeme par decomposition en valeurs singulieres est illustre dans le domaine du traitement de signal et l'AWFS basee sur le controle independant des modes de rayonnement est simulee (chapitre 8). Ce qui constitue la troisieme originalite principale de cette these. Ces simulations du traitement de signal montrent l'efficacite des algorithmes et la capacite de l'AWFS a attenuer les erreurs attribuables a des reflexions acoustiques. Le neuvieme chapitre presente des resultats experimentaux d'AWFS. L'objectif etait de valider la methode et d'evaluer les performances de l'AWFS. Un autre algorithme prometteur est aussi teste. Les resultats demontrent la bonne marche de l'AWFS et des algorithmes testes. Autant dans le cas de la reproduction de champs harmoniques que dans le cas de la reproduction de champs a large bande, l'AWFS reduit l'erreur de reproduction de la WFS et les effets indesirables causes par les lieux de reproduction.

Chemical abundances of fast-rotating massive stars. I. Description of the methods and individual results

NASA Astrophysics Data System (ADS)

Cazorla, Constantin; Morel, Thierry; Nazé, Yaël; Rauw, Gregor; Semaan, Thierry; Daflon, Simone; Oey, M. S.

2017-07-01

Aims: Recent observations have challenged our understanding of rotational mixing in massive stars by revealing a population of fast-rotating objects with apparently normal surface nitrogen abundances. However, several questions have arisen because of a number of issues, which have rendered a reinvestigation necessary; these issues include the presence of numerous upper limits for the nitrogen abundance, unknown multiplicity status, and a mix of stars with different physical properties, such as their mass and evolutionary state, which are known to control the amount of rotational mixing. Methods: We have carefully selected a large sample of bright, fast-rotating early-type stars of our Galaxy (40 objects with spectral types between B0.5 and O4). Their high-quality, high-resolution optical spectra were then analysed with the stellar atmosphere modelling codes DETAIL/SURFACE or CMFGEN, depending on the temperature of the target. Several internal and external checks were performed to validate our methods; notably, we compared our results with literature data for some well-known objects, studied the effect of gravity darkening, or confronted the results provided by the two codes for stars amenable to both analyses. Furthermore, we studied the radial velocities of the stars to assess their binarity. Results: This first part of our study presents our methods and provides the derived stellar parameters, He, CNO abundances, and the multiplicity status of every star of the sample. It is the first time that He and CNO abundances of such a large number of Galactic massive fast rotators are determined in a homogeneous way. Based on observations obtained with the Heidelberg Extended Range Optical Spectrograph (HEROS) at the Telescopio Internacional de Guanajuato (TIGRE) with the SOPHIE échelle spectrograph at the Haute-Provence Observatory (OHP; Institut Pytheas; CNRS, France), and with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph at the Magellan II Clay telescope. Based also on archival data from the Galactic O-Star Spectroscopic Survey (GOSSS), the Anglo-Australian Telescope (AAT) equipped with the University College London Echelle Spectrograph (UCLES), the ESO/La Silla Observatory with the Fiber-fed Extended Range Optical Spectrograph (FEROS; programmes 70.D-0110, 075.D-0061, 076.C-0431, 081.D-2008, 083.D-0589, 086.D-0997, 087.D-0946, 089.D-0189, 089.D-0975, 179.C-0197, and the High Accuracy Radial velocity Planet Searcher (HARPS; programme 60.A-9036), the Pic du Midi Observatory equipped with the NARVAL spectropolarimeter, the San Pedro Mártir (SPM) observatory with the Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations (ESPRESSO), the OHP with the AURELIE and ELODIE échelle spectrographs, the Nordic Optical Telescope (NOT) with the FIbre-fed Echelle Spectrograph (FIES), the Canada-France-Hawaii Telescope (CFHT), with the Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) spectrograph, the Leonhard Euler Telescope with the CORALIE spectrograph.Table F.2 is also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/603/A56

VizieR Online Data Catalog: NGC5897 red giant abundances (Koch+, 2014)

NASA Astrophysics Data System (ADS)

Koch, A.; McWilliam, A.

2014-03-01

Our observations were performed with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph at the 6.5-m Magellan2/Clay Telescope at Las Campanas Observatory, Chile. The data were gathered over four nights in May 2013. (2 data files).

High Resolution Spectrograph for the Hobby-Eberly Telescope

NASA Astrophysics Data System (ADS)

Tull, R. G.; MacQueen, P. J.; Good, J.; Epps, H. W.; HET HRS Team

1998-12-01

A fiber fed high-resolution spectrograph (HRS) is under construction for the Hobby-Eberly Telescope (HET). The primary resolving power originally specified, from astrophysical considerations, was R = 60,000 with a fiber of diameter at least 1 arc-second, with full spectral coverage limited only by the combined band-pass of the HET, the optical fiber, and the image detector. This was achieved in the final design with a high blaze angle R-4 echelle mosaic, white pupil design, image slicing, and a large area CCD mosaic illuminated by an eight element refractive camera. Two back-to-back, user selectable first-order diffraction gratings are employed for cross dispersion, to separate echelle spectral orders; the entire spectral range (420 - 1,000 nm) can be covered in as few as two exposures. Critical issues addressed in the design are cross dispersion and order spacing, sky subtraction, echelle and CCD selection, fiber optic feed and scrambling, and image or pupil slicing. In the final design meeting the requirements we exploited the large-area 4096 square CCD, image slicing, and the optical performance of the white-pupil design to acquire a range of 30,000 < R < 120,000 with fibers of diameter 2 and 3 arc-seconds, without sacrificing full spectral coverage. Design details will be presented. Limiting magnitude is projected to be about V = 19 (for S/N = 10) at the nominal R = 60,000 resolving power. The poster display will outline performance characteristics expected in relation to projected astrophysical research capabilities outlined by Sneden et al., in this conference. HRS is supported by generous grants from NSF, NASA, the State of Texas, and private philanthropy, with matching funds granted by the University of Texas and by McDonald Observatory.

An accessible echelle pipeline and its application to a binary star

NASA Astrophysics Data System (ADS)

Carmichael, Theron; Johnson, John Asher

2018-01-01

Nearly every star observed in the Galaxy has one or more companions that play an integral role in the evolution of the star. Whether it is a planet or another star, a companion opens up opportunities for unique forms of analysis to be done on a system. Some 2400 lightyears away, there is a 3-10 Myr old binary system called KH 15D, which not only includes two T Tauri K-type stars in a close orbit of 48 days, but also a truncated, coherently precessing warped disk in a circumbinary orbit.In binary systems, a double-lined spectroscopic binary may be observable in spectra. This is a spectrum that contains a mixture of each star's properties and manifests as two sets of spectral emission and absorption lines that correspond to each star. Slightly different is a single-lined spectroscopic binary, where only one set of spectral lines from one star is visible. The data of KH 15D are studied in the form of a double single-lined spectroscopic binary. This means that at two separate observing times, a single-lined spectroscopic binary is obtained from one of the stars of KH 15D. This is possible because of the circumbinary disk that blocks one star at a time from view.Here, we study this binary system with a combination of archival echelle data from the Keck Observatory and new echelle data from Las Campanas Observatory. This optical data is reduced with a new Python-based pipeline available on GitHub. The objective is to measure the mass function of the binary star and refine the current values of each star's properties.

Une approche communicative de la lecture (A Communicative Approach to Reading).

ERIC Educational Resources Information Center

Lehmann, Denis; Moirand, Sophie

1980-01-01

A number of classroom techniques are presented that illustrate the diversity of competencies necessary to reading in a second language, even more complex in their many combinations. It is proposed that evaluation of reading competence is difficult, if not impossible, by anyone but the student. (MSE)

Design and Construction of VUES: The Vilnius University Echelle Spectrograph

NASA Astrophysics Data System (ADS)

Jurgenson, Colby; Fischer, Debra; McCracken, Tyler; Sawyer, David; Giguere, Matt; Szymkowiak, Andrew; Santoro, Fernando; Muller, Gary

2016-03-01

In February 2014, the Yale Exoplanet Laboratory was commissioned to design, build, and deliver a high resolution (R=60,000) spectrograph for the 1.65m telescope at the Molėtai Astronomical Observatory. The observatory is operated by the Institute of Theoretical Physics and Astronomy at Vilnius University. The Vilnius University Echelle Spectrograph (VUES) is a white-pupil design that is fed via an octagonal fiber from the telescope and has an operational bandpass from 400nm to 880nm. VUES incorporates a novel modular optomechanical design that allows for quick assembly and alignment on commercial optical tables. This approach allowed the spectrograph to be assembled and commissioned at Yale using lab optical tables and then reassembled at the observatory on a different optical table with excellent repeatability. The assembly and alignment process for the spectrograph was reduced to a few days, allowing the spectrograph to be completely disassembled for shipment to Lithuania, and then installed at the observatory during a 10-day period in June of 2015.

Imaging spectroscopy of Mars in the thermal infrared: seasonal variations of H2O2 and mapping of the D/H ratio

NASA Astrophysics Data System (ADS)

Encrenaz, Therese; DeWitt, Curtis; Richter, Matthew; Greathouse, Thomas; Fouchet, Thierry; Lefevre, Franck; Montmessin, Franck; Forget, Francois; Bezard, Bruno; Atreya, Sushil

2017-04-01

Since 2002, we have been monitoring the spatial distribution and the seasonal variations of H2O2 on Mars, using high-resolution imaging spectroscopy with the Texas Echelon Cross Echelle Spectrograph (TEXES) at the Infrared Telescope Facility (IRTF) at Maunakea Observatory (Hawaii). These observations have shown that a better agreement with global climate models is obtained when heterogeneous chemistry is introduced in the photochemical model (Encrenaz et al. 2015, AA 578, A127). In addition, in April 2014, we have obtained a map of D/H on Mars using the Echelon Cross Echelle Spectrograph (EXES) aboard the stratospheric Observatory for Infrared Astronomy (SOFIA; Encrenaz et al. 2015, AA 586, A62). In 2016, new observations have been obtained on H2O2 with TEXES and on D/H with EXES, allowing us to better analyze the seasonal variations of these parameters. These data will be presented and compared with previous measurements.

HESP: Instrument control, calibration and pipeline development

NASA Astrophysics Data System (ADS)

Anantha, Ch.; Roy, Jayashree; Mahesh, P. K.; Parihar, P. S.; Sangal, A. K.; Sriram, S.; Anand, M. N.; Anupama, G. C.; Giridhar, S.; Prabhu, T. P.; Sivarani, T.; Sundararajan, M. S.

Hanle Echelle SPectrograph (HESP) is a fibre-fed, high resolution (R = 30,000 and 60,000) spectrograph being developed for the 2m HCT telescope at IAO, Hanle. The major components of the instrument are a) Cassegrain unit b) Spectrometer instrument. An instrument control system interacting with a guiding unit at Cassegrain interface as well as handling spectrograph functions is being developed. An on-axis auto-guiding using the spill-over angular ring around the input pinhole is also being developed. The stellar light from the Cassegrain unit is taken to the spectrograph using an optical fiber which is being characterized for spectral transmission, focal ratio degradation and scrambling properties. The design of the thermal enclosure and thermal control for the spectrograph housing is presented. A data pipeline for the entire Echelle spectral reduction is being developed. We also plan to implement an instrument physical model based calibration into the main data pipeline and in the maintenance and quality control operations.

Spectroscopic Instrumentation in Undergraduate Astronomy Laboratories

NASA Astrophysics Data System (ADS)

Ludovici, Dominic; Mutel, Robert Lucien; Lang, Cornelia C.

2017-01-01

We have designed and built two spectrographs for use in undergraduate astronomy laboratories at the University of Iowa. The first, a low cost (appx. $500) low resolution (R ~ 150 - 300) grating-prism (grism) spectrometer consists of five optical elements and is easily modified to other telescope optics. The grism spectrometer is designed to be used in a modified filter wheel. This type of spectrometer allows students to undertake projects requiring sensitive spectral measurements, such as determining the redshifts of quasars. The second instrument is a high resolution (R ~ 8000), moderate cost (appx. $5000) fiber fed echelle spectrometer. The echelle spectrometer will allow students to conduct Doppler measurements such as those used to study spectroscopic binaries. Both systems are designed to be used with robotic telescope systems. The availability of 3D printing enables both of these spectrographs to be constructed in hands-on instrumentation courses where students build and commission their own instruments. Additionally, these instruments enable introductory majors and non-majors laboratory students to gain experience conducting their own spectroscopic observations.

Optical design of the PEPSI high-resolution spectrograph at LBT

NASA Astrophysics Data System (ADS)

Andersen, Michael I.; Spano, Paolo; Woche, Manfred; Strassmeier, Klaus G.; Beckert, Erik

2004-09-01

PEPSI is a high-resolution, fiber fed echelle spectrograph with polarimetric capabilities for the LBT. In order to reach a maximum resolution R=120.000 in polarimetric mode and 300.000 in integral light mode with high efficiency in the spectral range 390-1050~nm, we designed a white-pupil configuration with Maksutov collimators. Light is dispersed by an R4 31.6 lines/mm monolithic echelle grating mosaic and split into two arms through dichroics. The two arms, optimized for the spectral range 390-550~nm and 550-1050~nm, respectively, consist of Maksutov transfer collimators, VPH-grism cross dispersers, optimized dioptric cameras and 7.5K x 7.5K 8~μ CCDs. Fibers of different core sizes coupled to different image-slicers allow a high throughput, comparable to that of direct feed instruments. The optical configuration with only spherical and cylindrical surfaces, except for one aspherical surface in each camera, reduces costs and guarantees high optical quality. PEPSI is under construction at AIP with first light expected in 2006.

PEPSI: the Potsdam Echelle Polarimetric and Spectroscopic Instrument for the LBT

NASA Astrophysics Data System (ADS)

Strassmeier, K. G.; Woche, M.; Ilyin, I.; Popow, E.; Bauer, S.-M.; Dionies, F.; Fechner, T.; Weber, M.; Hofmann, A.; Storm, J.; Materne, R.; Bittner, W.; Bartus, J.; Granzer, T.; Denker, C.; Carroll, T.; Kopf, M.; DiVarano, I.; Beckert, E.; Lesser, M.

2008-07-01

We present the status of PEPSI, the bench-mounted fibre-fed and stabilized "Potsdam Echelle Polarimetric and Spectroscopic Instrument" for the 2×8.4m Large Binocular Telescope in southern Arizona. PEPSI is under construction at AIP and is scheduled for first light in 2009/10. Its ultra-high-resolution mode will deliver an unprecedented spectral resolution of approximately R=310,000 at high efficiency throughout the entire optical/red wavelength range 390-1050nm without the need for adaptive optics. Besides its polarimetric Stokes IQUV mode, the capability to cover the entire optical range in three exposures at resolutions of 40,000, 130,000 and 310,000 will surpass all existing facilities in terms of light-gathering-power times spectral-coverage product. A solar feed will make use of the spectrograph also during day time. As such, we hope that PEPSI will be the most powerful spectrometer of its kind for the years to come.

VizieR Online Data Catalog: Accurate astrometry & RVs of 4 multiple systems (Tokovinin+, 2017)

NASA Astrophysics Data System (ADS)

Tokovinin, A.; Latham, D. W.

2017-10-01

The outer subsystems are classical visual binaries. Historic micrometric measurements and modern speckle interferometric data have been obtained from the WDS database on our request. Additionally, we secured new speckle astrometry and relative photometry of two systems at the 4.1m SOAR telescope. Published radial velocities (RVs) are used here together with the new data. The RVs were measured with the CfA Digital Speedometers, initially using the 1.5m Wyeth Reflector at the Oak Ridge Observatory in the town of Harvard, Massachusetts, and subsequently with the 1.5m Tillinghast Reflector at the Whipple Observatory on Mount Hopkins, Arizona. Starting in 2009, the new fiber-fed Tillinghast Reflector Echelle Spectrograph (TRES) was used. The spectral resolution was 44000 for all three spectrographs. Two objects, HIP 101955 and 103987, were observed in 2015 with the CHIRON echelle spectrograph at the 1.5m telescope at CTIO with a spectral resolution of 80000. (4 data files).

VizieR Online Data Catalog: Radial velocity follow-up of the HD 3167 system (Gandolfi+, 2017)

NASA Astrophysics Data System (ADS)

Gandolfi, D.; Barragan, O.; Hatzes, A. P.; Fridlund, M.; Fossati, L.; Donati, P.; Johnson, M. C.; Nowak, G.; Prieto-Arranz, J.; Albrecht, S.; Dai, F.; Deeg, H.; Endl, M.; Grziwa, S.; Hjorth, M.; Korth, J.; Nespral, D.; Saario, J.; Smith, A. M. S.; Antoniciello, G.; Alarcon, J.; Bedell, M.; Blay, P.; Brems, S. S.; Cabrera, J.; Csizmadia, S.; Cusano, F.; Cochran, W. D.; Eigmuller, P.; Erikson, A.; Gonzalez Hernandez, J. I.; Guenther, E. W.; Hirano, T.; Suarez Mascareno, A.; Narita, N.; Palle, E.; Parviainen, H.; Patzold, M.; Persson, C. M.; Rauer, H.; Saviane, I.; Schmidtobreick, L.; van Eylen, V.; Winn, J. N.; Zakhozhay, O. V.

2018-06-01

We used the FIbre-fed Echelle Spectrograph (FIES; Frandsen & Lindberg 1999anot.conf...71F; Telting et al. 2014AN....335...41T) mounted at the 2.56 m Nordic Optical Telescope (NOT) of Roque de los Muchachos Observatory (La Palma, Spain) to acquire 37 high-resolution spectra (R~67000) in 12 different nights between July and September 2016. We also acquired 50 spectra with the HARPS spectrograph (R~115000; Mayor et al. 2003Msngr.114...20M) and 32 spectra with the HARPS-N spectrograph (R~115000; Cosentino et al. 2012SPIE.8446E..1VC). HARPS and HARPS-N are fiber-fed cross-dispersed echelle spectrographs specifically designed to achieve very high-precision long-term RV stabilities (<1 m/s). They are mounted at the ESO-3.6 m telescope of La Silla observatory (Chile) and at the 3.58 m Telescopio Nazionale Galileo (TNG) of Roque de los Muchachos Observatory (La Palma, Spain). (1 data file).

TESS Follow-up Observing Programs at the University of Wyoming

NASA Astrophysics Data System (ADS)

Jang-Condell, Hannah; Kasper, David; Kar, Aman; Sorber, Rebecca; Hancock, Daniel A.; Leuquire, Jacob D.; Suhaimi, Afiq; Kobulnicky, Henry A.; Pierce, Michael; Pilachowski, Catherine A.

2018-06-01

The Transiting Exoplanet Survey Satellite (TESS), launched in Spring 2018, will detect thousands of new exoplanet candidates. These candidates will need to be vetted by ground-based observatories to rule out false positives. The Observatories at the University of Wyoming are well-positioned to take active roles in TESS Follow-Up Observing Program (TFOP) Working Groups. The 0.6-m Red Buttes Observatory has already demonstrated its capability to do precision photometric monitoring of transiting exoplanet targets as a participant in the Kilodegree Extremely Little Telescope Follow-Up Network (KELT-FUN). A new echelle spectrograph, Fiber High-Resolution Echelle (FHiRE), being built for the 2.3-m Wyoming InfraRed Observatory (WIRO), will enable precision radial velocity measurements of exoplanet candidates. Over 180 nights/year at both observatories will be available to our team to undertake follow-up observations of TESS Objects of Interest (TOIs). We anticipate making significant contributions to new exoplanet discoveries in the era of TESS.

A reduction package for cross-dispersed echelle spectrograph data in IDL

NASA Astrophysics Data System (ADS)

Hall, Jeffrey C.; Neff, James E.

1992-12-01

We have written in IDL a data reduction package that performs reduction and extraction of cross-dispersed echelle spectrograph data. The present package includes a complete set of tools for extracting data from any number of spectral orders with arbitrary tilt and curvature. Essential elements include debiasing and flatfielding of the raw CCD image, removal of scattered light background, either nonoptimal or optimal extraction of data, and wavelength calibration and continuum normalization of the extracted orders. A growing set of support routines permits examination of the frame being processed to provide continuing checks on the statistical properties of the data and on the accuracy of the extraction. We will display some sample reductions and discuss the algorithms used. The inherent simplicity and user-friendliness of the IDL interface make this package a useful tool for spectroscopists. We will provide an email distribution list for those interested in receiving the package, and further documentation will be distributed at the meeting.

Traduction et langues de specialite: Approches theoriques et considerations pedagogiques (Translation and Specialty Languages: Theoretical Approaches and Pedagogic Considerations).

ERIC Educational Resources Information Center

Guevel, Zelie, Ed.; Valentine, Egan, Ed.

Essays on the teaching of translation and on specialized translation, all in French, include: "Perspectives d'optimisation de la formation du traducteur: quelques reflexions" ("Perspectives on Optimization of Training of Translation Teachers: Some Reflections") (Egan Valentine); "L'enseignement de la revision…

Vers une approche plus rationnelle des temps verbaux (Toward a More Rational Approach to Verb Tenses).

ERIC Educational Resources Information Center

Montredon, Jacques

1983-01-01

Experiences in teaching French verb tenses to Japanese students are used to illustrate teaching techniques that not only help students acquire verb forms but also present them as a coherent linguistic unity tied to fundamental communicative needs. A variety of exercises are included. (MSE)

"Techniques d'expression,""approche communicative," meme combat? ("Expressive Techniques,""Communicative Approach," Same Struggle?)

ERIC Educational Resources Information Center

Vives, Robert

1983-01-01

Based on a literature review and analysis of teaching methods and objectives, it is proposed that the emphasis on communicative competence ascendant in French foreign language instruction is closely related to, and borrows from, expressive techniques taught in French native language instruction in the 1960s. (MSE)

Synthetic Strategies to Terpene Quinones/Hydroquinones

PubMed Central

Gordaliza, Marina

2012-01-01

The cytotoxic and antiproliferative properties of many natural sesquiterpene-quinones and -hydroquinones from sponges offer promising opportunities for the development of new drugs. A review dealing with different strategies for obtaining bioactive terpenyl quinones/hydroquinones is presented. The different synthetic approches for the preparation of the most relevant quinones/hydroquinones are described. PMID:22412807

On the design of the PEPSI spectropolarimeter for the LBT

NASA Astrophysics Data System (ADS)

Ilyin, I.; Strassmeier, K. G.; Woche, M.; Dionies, F.; Di Varano, I.

2011-10-01

We present the design concept of the spectropolarimeter for the high-resolution echelle spectrograph PEPSI to be installed at the 2×8.4 m Large Binocular Telescope (LBT) in Arizona. We discuss the optical key elements, the principles of operations of the instrument and its instrumental polarization effects.

VizieR Online Data Catalog: 6 cold-gas-bearing debris-disc stars spectra (Rebollido+, 2018)

NASA Astrophysics Data System (ADS)

Rebollido, I.; Eiroa, C.; Montesinos, B.; Maldonado, J.; Villaver, E.; Absi, O.; Bayo, A.; Canovas, H.; Carmona, A.; Chen, Ch.; Ertel, S.; Garufi, A.; Henning, T.; Iglesias, D. P.; Launhardt, R.; Liseau, R.; Meeus, G.; Moor, A.; Mora, A.; Olofsson, J.; Rauw, G.; Riviere-Marichalar, P.

2018-02-01

Spectra obtained with Mercator (La Palma, Spain), NOT (La Palma, Spain) and Tigre (La Luz, Mexico) echelle spectrographs. Observation dates range from September 2015 to July 2016. They were reduced using instrument pipelines. Barycentric correction has been applied to all spectra. (2 data files).

Diagnostic et traitement du prurit

PubMed Central

Nowak, Dominik; Yeung, Jensen

2017-01-01

Résumé Objectif Décrire une approche permettant une évaluation simplifiée et une différenciation précise des démangeaisons chez la plupart des patients dans les soins de première ligne, et offrir une mise à jour sur les traitements non pharmacologiques, topiques et systémiques à notre disposition. Sources d’information Une recherche a été effectuée dans MEDLINE (Ovid) et PubMed, à l’aide des mots-clés anglais itch ou pruritus. Pour chaque cause et chaque traitement relevé, la recherche a été affinée en ajoutant les mots-clés appropriés, et des recherches subséquentes ont été effectuées à la main dans les références des articles relevés. Message principal Il n’existe pas de bonnes données cumulées tirées d’essais de bonne qualité sur le traitement du prurit, et les traitements qui existent donnent des résultats variables. Les principales causes des démangeaisons généralisées sont la xérose et l’eczéma. Le problème se résorbe, dans la plupart des cas, à l’aide de traitements non pharmacologiques, y compris l’hydratation fréquente. En cas d’échec, des investigations plus poussées sont justifiées pour orienter le traitement subséquent à l’aide de l’une des nombreuses approches topiques et systémiques spécifiques à la cause qui sont disponibles. Conclusion Les démangeaisons chroniques peuvent être incapacitantes pour les patients. L’approche dont il est question ici permet de simplifier l’évaluation et de différencier de manière précise la plupart des démangeaisons dans les soins de première ligne. PMID:29237631

MSE spectrograph optical design: a novel pupil slicing technique

NASA Astrophysics Data System (ADS)

Spanò, P.

2014-07-01

The Maunakea Spectroscopic Explorer shall be mainly devoted to perform deep, wide-field, spectroscopic surveys at spectral resolutions from ~2000 to ~20000, at visible and near-infrared wavelengths. Simultaneous spectral coverage at low resolution is required, while at high resolution only selected windows can be covered. Moreover, very high multiplexing (3200 objects) must be obtained at low resolution. At higher resolutions a decreased number of objects (~800) can be observed. To meet such high demanding requirements, a fiber-fed multi-object spectrograph concept has been designed by pupil-slicing the collimated beam, followed by multiple dispersive and camera optics. Different resolution modes are obtained by introducing anamorphic lenslets in front of the fiber arrays. The spectrograph is able to switch between three resolution modes (2000, 6500, 20000) by removing the anamorphic lenses and exchanging gratings. Camera lenses are fixed in place to increase stability. To enhance throughput, VPH first-order gratings has been preferred over echelle gratings. Moreover, throughput is kept high over all wavelength ranges by splitting light into more arms by dichroic beamsplitters and optimizing efficiency for each channel by proper selection of glass materials, coatings, and grating parameters.

KECK NIRSPEC RADIAL VELOCITY OBSERVATIONS OF LATE-M DWARFS

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

Tanner, Angelle; White, Russel; Bailey, John

2012-11-15

We present the results of an infrared spectroscopic survey of 23 late-M dwarfs with the NIRSPEC echelle spectrometer on the Keck II telescope. Using telluric lines for wavelength calibration, we are able to achieve measurement precisions of down to 45 m s{sup -1} for our late-M dwarfs over a one- to four-year long baseline. Our sample contains two stars with radial velocity (RV) variations of >1000 m s{sup -1}. While we require more measurements to determine whether these RV variations are due to unseen planetary or stellar companions or are the result of starspots known to plague the surface ofmore » M dwarfs, we can place upper limits of <40 M{sub J} sin i on the masses of any companions around those two M dwarfs with RV variations of <160 m s{sup -1} at orbital periods of 10-100 days. We have also measured the rotational velocities for all the stars in our late-M dwarf sample and offer our multi-order, high-resolution spectra over 2.0-2.4 {mu}m to the atmospheric modeling community to better understand the atmospheres of late-M dwarfs.« less

Study Abroad as Professional Development for FSL Teachers

ERIC Educational Resources Information Center

Wernicke, Meike

2010-01-01

In July 2009, a group of over 80 FSL teachers from British Columbia (BC) participated in a two-week sojourn at the "Centre d'Approches vivantes des Langues et des Medias" (CAVILAM) in Vichy, France, as part of an initiative to address the critical shortage of qualified French language teachers in the province. After almost four decades…

La complexite de l'implantation de l'approche socio-constructiviste et de l'integration des TIC (The Complexity of Implementing the Socio-constructivist Approach and Integrating ICT).

ERIC Educational Resources Information Center

Viens, Jacques; Renaud, Luc

2001-01-01

The education programs of Quebec have a social constructivist focus characterized by project teaching, learner autonomy, cooperation, and metacognition. However, important technological and pedagogical hurdles must be overcome before these new practices can be implemented. (Author/SV)

An Integer Optimization Approch To A Probabilistic Reserve Site Selection Problem

Treesearch

Robert G. Haight; Charles S. Revelle; Stephanie A. Snyder

2000-01-01

Human economic and agricultural activities contribute to the endangerment of over 900 species that are currently listed or proposed for listing under the federal Endangered Species Act in the United States (Dobson et al. 1997). One approach to conserving the elements of biological diversity--including plants, animals, and ecological communities--is to establish and...

COURSE OUTLINE FOR SECOND SIX WEEKS OF SCIENCE-LEVEL III, TALENT PRESERVATION CLASSES.

ERIC Educational Resources Information Center

Houston Independent School District, TX.

EACH UNIT IS OF APPROXIMATELY 6 WEEKS' DURATION. UNITS ARE ON ENERGY AND THE HUMAN BODY, HEAT, ELECTRICITY AND MACHINES, CONSUMER SCIENCE FROM A COMMUNICATION AND PHYSICAL SCIENCE APPROACH, AND CONSUMER SCIENCE FROM BIOLOGICAL AND EARTH APPROCH. IN ALL UNITS, AS MANY CONCEPTS AS POSSIBLE SHOULD BE RELATED TO THE STUDENTS' EXPERIENCES. IN…

Development of Multiple-Element Flame Emission Spectrometer Using CCD Detection

ERIC Educational Resources Information Center

Seney, Caryn S.; Sinclair, Karen V.; Bright, Robin M.; Momoh, Paul O.; Bozeman, Amelia D.

2005-01-01

The full wavelength coverage of charge coupled device (CCD) detector when coupled with an echelle spectrography, the system allows for simultaneously multiple element spectroscopy to be performed. The multiple-element flame spectrometer was built and characterized through the analysis of environmentally significant elements such as Ca, K, Na, Cu,…

Follow-up spectroscopy and photometry of Dwarf Nova V392 Per

NASA Astrophysics Data System (ADS)

Mugrauer, M.; Gilbert, H.; Hoffmann, S.

2018-05-01

On 2018 May 1th 20 UT (JD=2458240.333) we took spectroscopic data of the dwarf nova V392 Per (ATel #11588; ATel #11601; ATel #11605) with the echelle spectrograph FLECHAS (Mugrauer et al. 2014, AN 335, 417) at the 90cm telescope of the University Observatory Jena.

Theory of Mind "Emotion", Developmental Characteristics and Social Understanding in Children and Adolescents with Intellectual Disabilities

ERIC Educational Resources Information Center

Thirion-Marissiaux, Anne-Francoise; Nader-Grosbois, Nathalie

2008-01-01

Patterns of development of ToM-emotion abilities in intellectually disabled (ID) children and typically developing (TD) children matched on their developmental age were investigated. The links between cognition, language, social understanding and ToM-emotion abilities were examined. EDEI-R (Perron-Borelli, M. (1996). "Echelles Differentielles…

Theory of Mind "Beliefs", Developmental Characteristics and Social Understanding in Children and Adolescents with Intellectual Disabilities

ERIC Educational Resources Information Center

Thirion-Marissiaux, Anne-Francoise; Nader-Grosbois, Nathalie

2008-01-01

Patterns of development of ToM belief abilities in intellectually disabled (ID) children and typically developing (TD) children matched on their developmental age were investigated. The links between cognition, language, social understanding and ToM belief abilities were examined. EDEI-R [Perron-Borelli M. (1996). "Echelles Differentielles…

NanoVipa: a miniaturized high-resolution echelle spectrometer, for the monitoring of young stars from a 6U Cubesat

NASA Astrophysics Data System (ADS)

Bourdarot, G.; Le Coarer, E.; Bonfils, X.; Alecian, E.; Rabou, P.; Magnard, Y.

2017-12-01

We introduce to astrophysical instrumentation and space optics the use of virtually imaged phased array (VIPA) to shrink échelle spectrometers and/or increase their resolution. Here, we report on both a concept of an echelle spectrometer with resolution R=50{,}000 (@653nm), which fits a 6U nanosatellite platform ({{1U= 10 cm × 10 cm × 10 cm}}), and on our laboratory tests on a R=200{,}000 demonstrator. The outline of our paper is as follows: Sect. 1 introduces our concept of a 6U payload comprising an échelle spectrometer based on the VIPA. We present also the science cases of monitoring young stars, and the wider science landscape amenable with larger telescopes. Section 2 gives a more detailed description of the VIPA and of its implementation in a cross-dispersed spectrometer. Section 3 shows the first results at R=200{,}000 we already achieved at the Institut de Planétologie et d'Astrophysique de Grenoble (IPAG). Finally, Sect. 4 is a discussion on the remaining technical points to study.

Calibration Efforts and Unique Capabilities of the HST Space Telescope Imaging Spectrograph

NASA Astrophysics Data System (ADS)

Monroe, TalaWanda R.; Proffitt, Charles R.; Welty, Daniel; Branton, Doug; Carlberg, Joleen K.; debes, John Henry; Lockwood, Sean; Riley, Allyssa; Sohn, Sangmo Tony; Sonnentrucker, Paule G.; Walborn, Nolan R.; Jedrzejewski, Robert I.

2018-01-01

The Space Telescope Imaging Spectrograph (STIS) continues to offer the astronomy community the ability to carry out innovative UV and optical spectroscopic and imaging studies, two decades after its deployment on the Hubble Space Telescope (HST). Most notably, STIS provides spectroscopy in the FUV and NUV, including high spectral resolution echelle modes, imaging in the FUV, optical spectroscopy, and coronagraphic capabilities. Additionally, spatial scanning on the CCD with the long-slits is now possible to enable very high S/N spectroscopic observations without saturation while mitigating telluric and fringing concerns in the far red and near-IR. This new mode may especially benefit the diffuse interstellar bands and exoplanet transiting communities. We present recent calibration efforts for the instrument, including work to optimize the calibration of the echelle spectroscopic modes by improving the flux agreement of overlapping spectral orders affected by changes in the grating blaze function since HST Servicing Mission 4. We also discuss considerations to maintain the wavelength precision of the spectroscopic modes, and the current capabilities of CCD spectroscopic spatial trails.

Design study of the PEPSI polarimeter for the LBT

NASA Astrophysics Data System (ADS)

Hofmann, A.; Strassmeier, K. G.; Woche, M.

2002-07-01

We present the conceptual design of the two polarimetric channels of the PEPSI spectropolarimeter for the Large Binocular Telescope (LBT). The two direct Gregorian f/15 focii of the LBT will take up two identical but independent full-Stokes IQUV polarimeters that themselves fiberfeed a high-resolution Echelle spectrograph (see the accompanying paper by Zerbi et al.). The polarizing units will be based on super-achromatic Fresnel-rhomb retarders and Foster prisms. A total of four fibers are foreseen to simultaneously direct two ordinary and two extraordinary light beams to the Echelle spectrograph. Both polarimetric units are layed out in a modular design, each one optimized to the polarization state in which it is used. A number of observing modes can be chosen that are optimized to the type of polarization that is expected from the target, e.g. circularly and linearly polarized light simultaneously, or linearly polarized light in both polarimeters, or integral light from one and polarized light from the other telescope, a.s.o.. Calibration would be provided for each polarimeter separately.

Ironing Out the Wrinkles

NASA Astrophysics Data System (ADS)

Ayres, Thomas

2009-07-01

This is a Calibration Archival proposal to develop, implement, and test enhancements to the pipeline wavelength scales of STIS echelle spectra, to take full advantage of the extremely high performance of which the instrument is capable. The motivation is a recent extensive investigation--The Deep Lamp Project--which identified systematic wavelength distortions in all 44 primary and secondary settings of the four STIS echelle modes: E140M, E140H, E230M, and E230H. The method was to process deep exposures of the onboard Pt/Cr-Ne calibration source as if they were science images, and measure deviations of the lamp lines from their laboratory wavelengths. An approach has been developed to correct the distortions post facto, but it would be preferable to implement a more robust dispersion model in the pipeline itself. The proposed study will examine a more extensive set of WAVECALs than in the exploratory Deep Lamp effort, and will benefit from a new laboratory line list specifically for the STIS lamps. Ironing out the wrinkles in the STIS wavelength scales will impact many diverse science investigations, especially the Legacy Archival project "StarCAT."

IMPROVED Ti II log(gf) VALUES AND ABUNDANCE DETERMINATIONS IN THE PHOTOSPHERES OF THE SUN AND METAL-POOR STAR HD 84937

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

Wood, M. P.; Lawler, J. E.; Sneden, C.

2013-10-01

Atomic transition probability measurements for 364 lines of Ti II in the UV through near-IR are reported. Branching fractions from data recorded using a Fourier transform spectrometer (FTS) and a new echelle spectrometer are combined with published radiative lifetimes to determine these transition probabilities. The new results are in generally good agreement with previously reported FTS measurements. Use of the new echelle spectrometer, independent radiometric calibration methods, and independent data analysis routines enables a reduction of systematic errors and overall improvement in transition probability accuracy over previous measurements. The new Ti II data are applied to high-resolution visible and UVmore » spectra of the Sun and metal-poor star HD 84937 to derive new, more accurate Ti abundances. Lines covering a range of wavelength and excitation potential are used to search for non-LTE effects. The Ti abundances derived using Ti II for these two stars match those derived using Ti I and support the relative Ti/Fe abundance ratio versus metallicity seen in previous studies.« less

VizieR Online Data Catalog: Radial velocities of HD 133131A and HD 133131B (Teske+, 2016)

NASA Astrophysics Data System (ADS)

Teske, J. K.; Shectman, S. A.; Vogt, S. S.; Diaz, M.; Butler, R. P.; Crane, J. D.; Thompson, I. B.; Arriagada, P.

2017-05-01

The radial velocity observations of HD133131A and B are part of the large Magellan Planet Search Program, which began in 2002 and is surveying a sample of ~500 of the nearest stars (<100pc). The survey was started with observations from the Magellan Inamori Kyocera Echelle (MIKE) echelle spectrograph, mounted for a limited time on the Magellan I (Baade), but mostly on Magellan II (Clay), 6.5m telescopes at Las Campanas Observatory. In 2010, the survey switched to using the Carnegie Planet Finder Spectrograph (PFS), a temperature-controlled high-resolution echelle spectrograph built for precision radial velocity observations, on Magellan II. Only HD133131A observations from MIKE are included here. Using a 0.35*5'' slit, MIKE provides spectra with R~70000 in the blue and ~50000 in the red and covers 3900-6200Å. Only the red MIKE orders are used for radial velocity determination, while the blue orders provide coverage of the CaIIH and K lines for monitoring stellar activity. The MIKE observations of HD133131A span 2003 June to 2009 July, with total exposure times ranging from 150 to 600s, depending on observing conditions. Both HD133131A and B were observed with PFS, the former observations ranging from 2010 February to 2015 September, and the latter from 2010 August to 2015 September. PFS has a more limited wavelength range than MIKE (3880-6680Å), but still covers the entire iodine wavelength region, CaIIH and K, and Hα. We use a 0.5*2.5'' slit for target observations, providing R~80000 in the iodine region. The total exposure times for the A component range from 285 to 720s, and for the B component range from 282 to 800s. (6 data files).

Compact high-resolution echelle-AOTF NIR spectrometer for atmospheric measurements

NASA Astrophysics Data System (ADS)

Korablev, Oleg I.; Bertaux, Jean-Loup; Vinogradov, Imant I.; Kalinnikov, Yurii K.; Nevejans, D.; Neefs, E.; Le Barbu, T.; Durry, G.

2017-11-01

A new concept of a high-resolution near-IR spectrometer consisting of an echelle grating combined with an acousto-optic tunable filter (AOTF) for separation of diffraction orders, is developed for space-borne studies of planetary atmospheres. A compact design with no moving parts within the mass budget of 3-5 kg allows to reach the resolving power λ/Δλ of 20000-30000. Only a small piece of spectrum in high diffraction orders can be measured at a time, but thanks to flexibility of the AOTF electrical tuning, such pieces of spectrum can be measured randomly and rapidly within the spectral range. This development can be used for accurate measurements of important atmospheric gases, such as CO2 in terrestrial atmosphere, isotopic ratios and minor gases. A spectrometer, based on this principle, SOIR (Solar Occultation InfraRed) is being built for Venus Express (2005) ESA mission. Instruments based on this principle have high potential for the studies of the Earth, in particular for measurements of isotopes of water in the lower atmosphere, either in solar occultation profiling (tangent altitude <10 km), or observing solar glint for integral quantities of the components. Small size of hardware makes them ideal for micro-satellites, which are now agile enough to provide necessary pointing for solar occultation or glint observations. Also, the atmosphere of Mars has never been observed at local scales with such a high spectral resolution. A laboratory prototype consisting of 275-mm echelle spectrometer with Hamamatsu InGaAs 512-pixel linear array and the AOTF has demonstrated λ/Δλ≍30000 in the spectral range of 1-1.7 μm. The next set up, covering the spectral ranges of 1-1.7 μm and 2.3-4.3 μm, and the Venus Express SOIR are briefly discussed.

Optimization of an Advanced Multi-Junction Solar-Cell Design for Space Environments (AM0) Using Nearly Orthogonal Latin Hypercubes

DTIC Science & Technology

2017-06-01

AN ADVANCED MULTI-JUNCTION SOLAR -CELL DESIGN FOR SPACE ENVIRONMENTS (AM0) USING NEARLY ORTHOGONAL LATIN HYPERCUBES by Silvio Pueschel June...ADVANCED MULTI-JUNCTION SOLAR -CELL DESIGN FOR SPACE ENVIRONMENTS (AM0) USING NEARLY ORTHOGONAL LATIN HYPERCUBES 5. FUNDING NUMBERS 6. AUTHOR(S) Silvio...multi-junction solar cells with Silvaco Atlas simulation software. It introduces the nearly orthogonal Latin hypercube (NOLH) design of experiments (DoE

A Case Study in User Support for Managing OpenSim Based Multi User Learning Environments

ERIC Educational Resources Information Center

Perera, Indika; Miller, Alan; Allison, Colin

2017-01-01

Immersive 3D Multi User Learning Environments (MULE) have shown sufficient success to warrant their consideration as a mainstream educational paradigm. These are based on 3D Multi User Virtual Environment platforms (MUVE), and although they have been used for various innovative educational projects their complex permission systems and large…

Le programme "La francophonie": Une approche internationale et interdisciplinaire (The Francophony Program: An International and Interdisciplinary Approach).

ERIC Educational Resources Information Center

Bras, Monique

The origins, development, and organization of a set of instructional materials entitled "La Francophonie" at North Carolina Central University are described. The project grew out of American students' disaffection for language learning in the mid 1960's and the narrow focus of much college-level instruction. The program consists of two…

Approche pedagogique d'un classique du cinema quebecois: Mon Oncle Antoine (Instructional Approach to a Quebec Film Classic: My Uncle Antoine).

ERIC Educational Resources Information Center

Viswanathan, Jacqueline

1990-01-01

An approach that introduces a Quebec film into a college-level course for advanced students of French is described. The technique addresses three aspects of the film: organization; the significance of certain film-making processes; and cultural and social aspects of the film as they relate to Quebecoise culture. (MSE)

Etude vibroacoustique d'un systeme coque-plancher-cavite avec application a un fuselage simplifie

NASA Astrophysics Data System (ADS)

Missaoui, Jemai

L'objectif de ce travail est de developper des modeles semi-analytiques pour etudier le comportement structural, acoustique et vibro-acoustique d'un systeme coque-plancher-cavite. La connection entre la coque et le plancher est assuree en utilisant le concept de rigidite artificielle. Ce concept de modelisation flexible facilite le choix des fonctions de decomposition du mouvement de chaque sous-structure. Les resultats issus de cette etude vont permettre la comprehension des phenomenes physiques de base rencontres dans une structure d'avion. Une approche integro-modale est developpee pour calculer les caracteristiques modales acoustiques. Elle utilise une discretisation de la cavite irreguliere en sous-cavites acoustiques dont les bases de developpement sont connues a priori. Cette approche, a caractere physique, presente l'avantage d'etre efficace et precise. La validite de celle-ci a ete demontree en utilisant des resultats disponibles dans la litterature. Un modele vibro-acoustique est developpe dans un but d'analyser et de comprendre les effets structuraux et acoustiques du plancher dans la configuration. La validite des resultats, en termes de resonance et de fonction de transfert, est verifiee a l'aide des mesures experimentales realisees au laboratoire.

Algorithmes et architectures pour ordinateurs quantiques supraconducteurs

NASA Astrophysics Data System (ADS)

Blais, Alexandre

Depuis sa formulation, la theorie de l'information a ete basee, implicitement, sur les lois de la physique classique. Une telle formulation est toutefois incomplete puisqu'elle ne tient pas compte de la realite quantique. Au cours des vingt dernieres annees, l'expansion de la theorie de l'information englobant les effets purement quantiques a connu un interet grandissant. La realisation d'un systeme de traitement de l'information quantique, un ordinateur quantique, presente toutefois de nombreux defis. Dans ce document, on s'interesse a differents aspects concernant ces defis. On commence par presenter des concepts algorithmiques comme l'optimisation de calculs quantiques et le calcul quantique geometrique. Par la suite, on s'interesse au design et a differents aspects de l'utilisation de qubits bases sur les jonctions Josephson. En particulier, un nouveau design de qubit supraconducteur est suggere. On presente aussi une approche originale pour l'interaction entre qubits. Cette approche est tres generale puisqu'elle peut etre appliquee a differents designs de qubits. Finalement, on s'interesse a la lecture des qubits supraconducteurs de flux. Le detecteur suggere ici a l'avantage de pouvoir etre decouple du qubit lorsqu'il n'y a pas de mesure en cours.

VizieR Online Data Catalog: New FeI level energies from stellar spectra. II. (Peterson+, 2017)

NASA Astrophysics Data System (ADS)

Peterson, R. C.; Kurucz, R. L.; Ayres, T. R.

2017-06-01

All of the new space-based UV spectra were obtained at a two-pixel resolution of 110000 with the E230H echelle grating of the Space Telescope Imaging Spectrograph (STIS) on HST, under program GO-14161 (R. Peterson, PI). See section 2 for further explanations. (2 data files).

An Operational Implementation of a CBRN Sensor-Driven Modeling Paradigm for Stochastic Event Reconstruction

DTIC Science & Technology

2010-05-01

Eight (GS) and Twenty (G20) Summits , Francophonie Summit]. iv DRDC Suffield TR 2010-070 Somma ire An Operational Implementation of a CBRN Sensor...terrain Joint Urban 2003 effectuee a Oklahoma City, Okla- homa ), qui comprend le transport et la dispersion d’un agent a une echelle complexe urbaine

Self-Efficacy Beliefs amongst Parents of Young Children: Validation of a Self-Report Measure

ERIC Educational Resources Information Center

Meunier, Jean-Christophe; Roskam, Isabelle

2009-01-01

The self-efficacy belief (SEB) concept is discussed in the context of parenting. A questionnaire, the "Echelle Globale du Sentiment de Competence Parentale" (EGSCP), assessing several domain-specific SEBs and three related cognitive constructs, was developed with 705 French-speaking parents of 3- to 7-year-old children. The EGSCP displayed good…

The opto-mechanical design of the GMT-Consortium Large Earth Finder (G-CLEF)

NASA Astrophysics Data System (ADS)

Mueller, Mark; Szentgyorgyi, Andrew; Baldwin, Daniel; Bean, Jacob; Ben-Ami, Sagi; Brennan, Patricia; Budynkiewicz, J.; Chun, Moo-Yung; Crane, Jeffrey D.; Epps, Harland; Evans, Ian; Evans, Janet; Foster, Jeff; Frebel, Anna; Gauron, Thomas; Glenday, Alex; Hare, Tyson; Jang, Bi-Ho; Jang, Jeong-Gyun; Jordan, Andreas; Kim, Jihun; Kim, Kang-Min; Mendes de Oliveira, Claudia; Lopez-Morales, Mercedes; McCracken, Kenneth; McMuldroch, Stuart; Miller, Joseph; Oh, Jae Sok; Onyuksel, Cem; Ordway, Mark; Park, Chan; Park, Sung-Joon; Paxson, Charles; Phillips, David; Plummer, David; Podgorski, William; Seifahrt, Andreas; Steiner, Joao; Uomoto, Alan; Walsworth, Ronald; Yu, Young-Sam

2016-08-01

The GMT-Consortium Large Earth Finder (G-CLEF) is a fiber-fed, optical echelle spectrograph selected as the first light instrument for the Giant Magellan Telescope (GMT) now under construction at the Las Campanas Observatory in Chile. G-CLEF has been designed to be a general-purpose echelle spectrograph with precision radial velocity (PRV) capability for exoplanet detection. The radial velocity (RV) precision goal of G-CLEF is 10 cm/sec, necessary for detection of Earth-sized exoplanets. This goal imposes challenging stability requirements on the optical mounts and the overall spectrograph support structures especially when considering the instrument's operational environment. The accuracy of G-CLEF's PRV measurements will be influenced by minute changes in temperature and ambient air pressure as well as vibrations and micro gravity-vector variations caused by normal telescope slewing. For these reasons we have chosen to enclose G-CLEF's spectrograph in a well-insulated, vibration isolated vacuum chamber in a gravity invariant location on GMT's azimuth platform. Additional design constraints posed by the GMT telescope include: a limited space envelope, a thermal emission ceiling, and a maximum weight allowance. Other factors, such as manufacturability, serviceability, available technology and budget are also significant design drivers. All of the above considerations must be managed while ensuring performance requirements are achieved. In this paper, we discuss the design of G-CLEF's optical mounts and support structures including the choice of a low coefficient of thermal expansion (CTE) carbon-fiber optical bench to minimize the system's sensitivity to thermal soaks and gradients. We discuss design choices made to the vacuum chamber geared towards minimize the influence of daily ambient pressure variations on image motion during observation. We discuss the design of G-CLEF's insulated enclosure and thermal control systems which will maintain the spectrograph at milli-Kelvin level stability while simultaneously limiting thermal emissions into the telescope dome. Also discussed are micro gravity-vector variations caused by normal telescope slewing, their uncorrected influence on image motion, and how they are dealt with in the design. Finally, we discuss G-CLEF's front-end assembly and fiber-feed system as well as other interface challenges presented by the telescope, enclosure and neighboring instrumentation.

The opto-mechanical design of the GMT-consortium large earth finder (G-CLEF)

NASA Astrophysics Data System (ADS)

Mueller, Mark; Baldwin, Daniel; Bean, Jacob; Bergner, Henry; Bigelow, Bruce; Chun, Moo-Young; Crane, Jeffrey; Foster, Jeff; Fżrész, Gabor; Gauron, Thomas; Guzman, Dani; Hertz, Edward; Jordán, Andrés.; Kim, Kang-Min; McCracken, Kenneth; Norton, Timothy; Ordway, Mark; Park, Chan; Park, Sang; Podgorski, William A.; Szentgyorgyi, Andrew; Uomoto, Alan; Yuk, In-Soo

2014-08-01

The GMT-Consortium Large Earth Finder (G-CLEF) is a fiber fed, optical echelle spectrograph that has been selected as a first light instrument for the Giant Magellan Telescope (GMT) currently under construction at the Las Campanas Observatory in Chile's Atacama desert region. We designed G-CLEF as a general-purpose echelle spectrograph with precision radial velocity (PRV) capability used for exoplanet detection. The radial velocity (RV) precision goal of GCLEF is 10 cm/sec, necessary for detection of Earth-sized planets orbiting stars like our Sun in the habitable zone. This goal imposes challenging stability requirements on the optical mounts and the overall spectrograph support structures. Stability in instruments of this type is typically affected by changes in temperature, orientation, and air pressure as well as vibrations caused by telescope tracking. For these reasons, we have chosen to enclose G-CLEF's spectrograph in a thermally insulated, vibration isolated vacuum chamber and place it at a gravity invariant location on GMT's azimuth platform. Additional design constraints posed by the GMT telescope include: a limited space envelope, a thermal emission ceiling, and a maximum weight allowance. Other factors, such as manufacturability, serviceability, available technology and budget are also significant design drivers. All of the previously listed considerations must be managed while ensuring that performance requirements are achieved. In this paper, we discuss the design of G-CLEF's optical mounts and support structures including technical choices made to minimize the system's sensitivity to thermal gradients. A more general treatment of the properties of G-CLEF can be found elsewhere in these proceedings1. We discuss the design of the vacuum chamber which houses the irregularly shaped optical bench and optics while conforming to a challenging space envelope on GMT's azimuth platform. We also discuss the design of G-CLEF's insulated enclosure and thermal control systems which maintain the spectrograph at milli-Kelvin level stability while simultaneously limiting the maximum thermal emission into the telescope dome environment. Finally, we discuss G-CLEF's front-end assembly and fiber-feed system as well as other interface challenges presented by the telescope, enclosure and neighboring instrumentation.

Infrared Spectroscopy of Disilicon-Carbide Si_2C

NASA Astrophysics Data System (ADS)

Witsch, Daniel; Lutter, Volker; Fuchs, Guido W.; Gauss, Jürgen; Giesen, Thomas

2017-06-01

Small silicon and carbon containing molecules are thought to be important building blocks of interstellar grains. Some of them have been detected in circumstellar environments of late-type stars by means of rotational spectroscopy e.g., SiC, SiC_2, Si_2C, c-SiC_3, SiC_4, while centro-symmetric species, e.g., C_3, C_4, C_5, Si_2C_2, Si_2C_3, can only be detected by vibrational transitions, mainly in the infrared. In view of a new generation of high resolution infrared telescope instruments, e.g., EXES (Echelon-Cross-Echelle Spectrograph) onboard SOFIA (Observatory for Infrared Astronomy) and TEXES (Texas Echelon Cross Echelle Spectrograph) at the Gemini-North observatory, accurate laboratory data of small silicon-carbides in the infrared region are of high demand. In this talk we present first laboratory data of the Si_2C asymmetric stretching mode at 1200 cm^{-1}. A pulsed Nd:YAG-laser is used to vaporize a solid target of silicon exposed to a dilute sample of methane in helium buffer gas. Si_2C is formed in an adiabatic expansion of a supersonic jet and radiation of a quantum cascade laser is used to record rotationally resolved spectra. To date, 160 ro-vibrational lines and have been assigned to the asymmetric stretching vibration of Si_2C, and derived molecular parameters are in excellent agreement with ab initio calculations. In our global fit analysis recently published microwave laboratory data (McCarthy et al. 2015) and astronomical data (Cernicharo et al. 2015) were taken into account. Our new results allow for the identification of Si_2C by means of high resolution infrared astronomy towards the warm background of carbon-rich stars. McCarthy M.C., Baraban J.H., Changala P.B., Stanton J.F., Martin-Drumel M.A, Thorwirth S., et al., J. Chem. Phys. Lett. 6, 2107-2111 (2015). Cernicharo J., McCarthy M.C., Gottlieb C.A., Agundez M., Velilla Prieto L., Baraban J.H., et al. Astrophys. J. Lett. 806,L3 (2015).

A Multi-object Exoplanet Detecting Technique

NASA Astrophysics Data System (ADS)

Zhang, K.

2011-05-01

Exoplanet exploration is not only a meaningful astronomical action, but also has a close relation with the extra-terrestrial life. High resolution echelle spectrograph is the key instrument for measuring stellar radial velocity (RV). But with higher precision, better environmental stability and higher cost are required. An improved technique of RV means invented by David J. Erskine in 1997, External Dispersed Interferometry (EDI), can increase the RV measuring precision by combining the moderate resolution spectrograph with a fixed-delay Michelson interferometer. LAMOST with large aperture and large field of view is equipped with 16 multi-object low resolution fiber spectrographs. And these spectrographs are capable to work in medium resolution mode (R=5{K}˜10{K}). LAMOST will be one of the most powerful exoplanet detecting systems over the world by introducing EDI technique. The EDI technique is a new technique for developing astronomical instrumentation in China. The operating theory of EDI was generally verified by a feasibility experiment done in 2009. And then a multi-object exoplanet survey system based on LAMOST spectrograph was proposed. According to this project, three important tasks have been done as follows: Firstly, a simulation of EDI operating theory contains the stellar spectrum model, interferometer transmission model, spectrograph mediation model and RV solution model. In order to meet the practical situation, two detecting modes, temporal and spatial phase-stepping methods, are separately simulated. The interference spectrum is analyzed with Fourier transform algorithm and a higher resolution conventional spectrum is resolved. Secondly, an EDI prototype is composed of a multi-object interferometer prototype and the LAMOST spectrograph. Some ideas are used in the design to reduce the effect of central obscuration, for example, modular structure and external/internal adjusting frames. Another feasibility experiment was done at Xinglong Station in 2010. A related spectrum reduction program and the instrumental stability were tested by obtaining some multi-object interference spectrum. Thirdly, studying the parameter optimization of fixed-delay Michelson interferometer is helpful to increase its inner thermal stability and reduce the external environmental requirement. Referring to Wide-angle Michelson Interferometer successfully used in Upper Atmospheric Wind field, a glass pair selecting scheme is given. By choosing a suitable glass pair of interference arms, the RV error can be stable as several hundred m\\cdots^{-1}\\cdot{dg}C^{-1}. Therefore, this work is helpful to deeply study EDI technique and speed up the development of multi-object exoplanet survey system. LAMOST will make a greater contribution to astronomy when the combination between its spectrographs and EDI technique comes true.

Generating Computer Forensic Super Timelines under Linux: A Comprehensive Guide for Windows-based Disk Images

DTIC Science & Technology

2011-10-01

mémorandum technique fournit donc une description détaillée de l’approche des auteurs pour produire des calendriers des événements plus détaillés dans...SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT

An Improvement of Robust Biometrics-Based Authentication and Key Agreement Scheme for Multi-Server Environments Using Smart Cards.

PubMed

Moon, Jongho; Choi, Younsung; Jung, Jaewook; Won, Dongho

2015-01-01

In multi-server environments, user authentication is a very important issue because it provides the authorization that enables users to access their data and services; furthermore, remote user authentication schemes for multi-server environments have solved the problem that has arisen from user's management of different identities and passwords. For this reason, numerous user authentication schemes that are designed for multi-server environments have been proposed over recent years. In 2015, Lu et al. improved upon Mishra et al.'s scheme, claiming that their remote user authentication scheme is more secure and practical; however, we found that Lu et al.'s scheme is still insecure and incorrect. In this paper, we demonstrate that Lu et al.'s scheme is vulnerable to outsider attack and user impersonation attack, and we propose a new biometrics-based scheme for authentication and key agreement that can be used in multi-server environments; then, we show that our proposed scheme is more secure and supports the required security properties.

Observations of hydrogen-rich supernovae in the first days after explosion and new instruments to study them

NASA Astrophysics Data System (ADS)

Rubin, Adam; PTF

2018-01-01

I will discuss our results studying light curves of hydrogen-rich supernovae during the first few days after explosion. The first days of emission encode important information about the physical system, and it is possible to relate the early-time light curve to the radius of the progenitor star by using shock-cooling models. I will show the first systematic application of these models to data from the Palomar Transient Factory (PTF). We found that R-band data alone at PTF cadence cannot constrain the radius but can constrain the energy per unit mass of the explosion, uncovering new correlations with other supernova observables. We constrained the radii for events with multi-wavelength observations, and for two events observed with the Kepler mission at 30 min cadence. I will discuss improved observing strategies to obtain more constraining results in the future. Some tensions have arisen between our results and the expected radii from identified progenitors of hydrogen-rich supernovae. The resolution of these tensions may be related to the effect of circumstellar material on the light curves, motivating future systematic spectroscopic sequencing of these events. To this end, we have designed a new medium resolution UV-VIS spectrograph. The Multi-Imaging Transient Spectrograph (MITS) is the R~4500 UV-VIS arm of the Son Of X-Shooter (SOXS) spectrograph proposed for ESO’s 3.6 m New Technology Telescope. Our design divides the spectrum into several sub-bands, allowing optimization for each narrow part of the spectrum. We estimate a 50-100% improvement in throughput relative to a classical 4-C echelle design. Our design has passed a preliminary design review and is expected on the telescope in early 2021.

Inspiring Equal Contribution and Opportunity in a 3D Multi-User Virtual Environment: Bringing Together Men Gamers and Women Non-Gamers in Second Life[R

ERIC Educational Resources Information Center

deNoyelles, Aimee; Seo, Kay Kyeong-Ju

2012-01-01

A 3D multi-user virtual environment holds promise to support and enhance student online learning communities due to its ability to promote global synchronous interaction and collaboration, rich multisensory experience and expression, and elaborate design capabilities. Second Life[R], a multi-user virtual environment intended for adult users 18 and…

The Time-Dependent Sensitivity of the MAMA and CCD Long-Slit Gratings

NASA Astrophysics Data System (ADS)

Holland, Stephen T.; Aloisi, Alessandra; Bostroem, Azalee; Oliveria, Cristina; Proffitt, Charles

2014-12-01

We present the results of observing flux standard stars used to determine trends in the sensitivities of the five STIS low-resolution, long-slit gratings between 1997 and 2013. Also, the assumption that the sensitivity trends for the medium-resolution and echelle gratings are the same as those for the corresponding low-resolution gratings is tested.

VizieR Online Data Catalog: Chemical compositions of 11 RR Lyrae (For+, 2011)

NASA Astrophysics Data System (ADS)

For, B.-Q.; Sneden, C.; Preston, G. W.

2012-01-01

The spectroscopic data were obtained with the du Pont 2.5m telescope at the Las Campanas Observatory (LCO), using a cross-dispersed echelle spectrograph with a total wavelength coverage of 3500-9000Å. See Section 3 of For et al. 2011, Cat. J/ApJS/194/38, for details of data reduction. (4 data files).

Affordable spectroscopy for 1m-class telescopes: recent developments and applications

NASA Astrophysics Data System (ADS)

Csák, B.; Kovács, J.; Szabó, Gy. M.; Kiss, L. L.; Dózsa, Á.; Sódor, Á.; Jankovics, I.

2014-03-01

Doppler observations of exoplanet systems have been a very expensive technique, mainly due to the high costs of high-resolution stable spectrographs. Recent advances in instrumentation enable affordable Doppler planet detections with surprisingly small optical telescopes. We investigate the possibility of measuring Doppler reflex motion of planet hosting stars with small-aperture telescopes that have traditionally been neglected for this kind of studies. After thoroughly testing the recently developed and commercially available Shelyak eShel echelle spectrograph, we demonstrated that it is routinely possible to achieve velocity precision at the 100 m s-1 level, reaching down to ¬± 50 m s-1 for the best cases. We describe our off-the-shelf instrumentation, including a new 0.5m RC telescope at the Gothard Astrophysical Observatory of Loránd E&ötv&ös University equipped with an intermediate resolution fiber-fed echelle spectrograph. We present some follow-up radial velocity measurements of planet hosting stars and point out that updating the orbital solution of Doppler-planets is a very important task that can be fulfilled with sub-meter sized optical telescopes without requesting very expensive telescope times on 2—4 m (or larger) class telescopes.

Open source pipeline for ESPaDOnS reduction and analysis

NASA Astrophysics Data System (ADS)

Martioli, Eder; Teeple, Doug; Manset, Nadine; Devost, Daniel; Withington, Kanoa; Venne, Andre; Tannock, Megan

2012-09-01

OPERA is a Canada-France-Hawaii Telescope (CFHT) open source collaborative software project currently under development for an ESPaDOnS echelle spectro-polarimetric image reduction pipeline. OPERA is designed to be fully automated, performing calibrations and reduction, producing one-dimensional intensity and polarimetric spectra. The calibrations are performed on two-dimensional images. Spectra are extracted using an optimal extraction algorithm. While primarily designed for CFHT ESPaDOnS data, the pipeline is being written to be extensible to other echelle spectrographs. A primary design goal is to make use of fast, modern object-oriented technologies. Processing is controlled by a harness, which manages a set of processing modules, that make use of a collection of native OPERA software libraries and standard external software libraries. The harness and modules are completely parametrized by site configuration and instrument parameters. The software is open- ended, permitting users of OPERA to extend the pipeline capabilities. All these features have been designed to provide a portable infrastructure that facilitates collaborative development, code re-usability and extensibility. OPERA is free software with support for both GNU/Linux and MacOSX platforms. The pipeline is hosted on SourceForge under the name "opera-pipeline".

Can we use adaptive optics for UHR spectroscopy with PEPSI at the LBT?

NASA Astrophysics Data System (ADS)

Sacco, Germano G.; Pallavicini, Roberto; Spano, Paolo; Andersen, Michael; Woche, Manfred F.; Strassmeier, Klaus G.

2004-10-01

We investigate the potential of using adaptive optics (AO) in the V, R, and I bands to reach ultra-high resolution (UHR, R >= 200,000) in echelle spectrographs at 8-10m telescopes. In particular, we investigate the possibility of implementing an UHR mode for the fiber-fed spectrograph PEPSI (Potsdam Echelle Polarimetric and Spectrographic Instrument) being developed for the Large Binocular Telescope (LBT). By simulating the performances of the advanced AO system that will be available at first light at the LBT, and by using first-order estimates of the spectrograph performances, we calculate the total efficiency and signal to noise ratio (SNR) of PEPSI in the AO mode for stars of different magnitudes, different fiber core sizes, and different fractions of incident light diverted to the wavefront sensor. We conclude that AO can provide a significant advantage, of up to a factor ~2 in the V, R and I bands, for stars brighter than mR ~ 12 - 13. However, if these stars are observed at UHR in non-AO mode, slit losses caused by the need to use a very narrow slit can be compensated more effectively by the use of image slicers.

AIRES: an Airborne Infra-Red Echelle Spectrometer for SOFIA

NASA Astrophysics Data System (ADS)

Erickson, E. F.; Haas, M. R.; Colgan, S. W. J.; Roellig, T.; Simpson, J. P.; Telesco, C. M.; Pina, R. K.; Young, E. T.; Wolf, J.

1997-12-01

The Stratospheric Observatory for Infrared Astronomy, SOFIA, is a 2.7 meter telescope which is scheduled to begin observations in a Boeing 747 in October 2001. Among other SOFIA science instruments recently selected for development is the facility spectrometer AIRES. AIRES is designed for studies of a broad range of phenomena occuring in the interstellar medium (ISM) which are uniquely enabled by SOFIA. Examples include accretion and outflow in protostars and young stellar objects, the morphology, dynamics, and excitation of neutral and ionized gas at the Galactic center, and the recycling of material to the ISM from evolved stars. Astronomers using AIRES will be able to select any wavelength from 17 to 210 mu m., with corresponding spectral resolving powers ranging from 60,000 to 4000 in less than a minute. This entire wavelength range is important because it contains spectral features, often widely separated in wavelength, which characterize fundamental ISM processes. AIRES will utilize two-dimensional detector arrays and a large echelle grating to achieve spectral imaging with excellent sensitivity and unparalleled angular resolution at these wavelengths. As a facility science instrument, AIRES will provide guest investigators frequent opportunities for far infrared spectroscopic observations when SOFIA begins operations.

VizieR Online Data Catalog: weak G-band stars abundances (Palacios+, 2016)

NASA Astrophysics Data System (ADS)

Palacios, A.; Jasniewicz, G.; Masseron, T.; Thevenin, F.; Itam-Pasquet, J.; Parthasarathy, M.

2016-05-01

Seventeen southern wGb stars were observed at La Silla, ESO Chile, with the high-efficiency Fiber-fed Extended Range Optical Spectrograph FEROS spectrograph mounted on the 2.2m telescope. FEROS is a bench-mounted, thermally controlled, prism-cross-dispersed echelle spectrograph, providing, in a single spectrogram spread over 39 orders, almost complete spectral coverage from ~350 to ~920nm at a resolution of 48000. The FEROS observations were carried out during an observing run between May 10 and 13, 2012. All these spectra were flat-fielded and calibrated by means of ThArNe exposures using standard processing tools available at ESO. In addition, two northern wGb stars, HD 18474 and HD 166208, were observed in service mode at the Observatoire du Pic du Midi, France, with the NARVAL spectrograph mounted on the Bernard Lyot 2.0m telescope. The NARVAL instrument consists of a bench-mounted cross-dispersed echelle spectrograph, fibre-fed from a Cassegrain-mounted polarimeter unit. It was used in its non-polarimetric mode; it provided almost complete spectral coverage from ~375 to ~1050nm at a resolution of 75000 in a single spectrogram spread over 40 orders. (6 data files).

VizieR Online Data Catalog: V-band photometry and RVs of V482 Persei system (Torres+, 2017)

NASA Astrophysics Data System (ADS)

Torres, G.; Lacy, C. H. S.; Fekel, F. C.; Wolf, M.; Muterspaugh, M. W.

2018-05-01

Differential photometry of V482 Per was obtained by measuring images collected with two different robotic telescopes: the URSA WebScope at the University of Arkansas at Fayetteville, AR, and the NFO WebScope near Silver City, NM. All observations were made through a Bessel V filter. Observations were made between 2001 December and 2016 January, and are presented in Tables 1 and 2. V482 Per was monitored spectroscopically with two different instruments. We observed it between 2009 November and 2017 February at the Harvard-Smithsonian Center for Astrophysics (CfA) with the Tillinghast Reflector Echelle Spectrograph (TRES) on the 1.5m Tillinghast reflector at the Fred L. Whipple Observatory (Mount Hopkins, AZ). The wavelength coverage is approximately 3900-9100Å, with a resolving power R~44000. From 2011 November through 2017 April, we additionally acquired 37 useful spectra of V482 Per with the Tennessee State University 2m Automatic Spectroscopic Telescope (AST) and a fiber-fed echelle spectrograph at the Fairborn Observatory in southeast Arizona. We used only the wavelength region from 4920 to 7100Å, with a resolving power R~15000 at 6000Å. (6 data files).

VizieR Online Data Catalog: Line list for stellar chemical abundances (Bedell+, 2014)

NASA Astrophysics Data System (ADS)

Bedell, M.; Melendez, J.; Bean, J. L.; Ramirez, I.; Leite, P.; Asplund, M.

2017-05-01

The five solar spectra used in this analysis were obtained with very high resolution and signal-to-noise ratios (S/Ns) characteristic of data used in past stellar abundance analyses. Two spectra were taken with the Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) instrument (Donati 2003, Solar Polarization (ASP Conf. Ser. 307), ed. J. Trujillo-Bueno & J. Sanchez Almeida (San Francisco, CA: ASP), 41) at the 3.6 m Canada-France-Hawaii Telescope on the night of 2013 March 4. The asteroids Ceres and Vesta were each observed in "star only" mode at a spectral resolving power R=81000. The remaining three solar spectra were taken with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph (Bernstein et al. 2003SPIE.4841.1694B) at the 6.5 m Magellan Clay telescope. The asteroid Vesta was observed twice and Iris was observed once during three separate observing runs spanning January to September of 2011. All observations were carried out in MIKE's standard setup with the 0.35 arcsec width slit, giving a spectral resolving power of R=83000 on the blue CCD and 65000 on the red CCD. (1 data file).

Using CeSiC for UV spectrographs for the WSO/UV

NASA Astrophysics Data System (ADS)

Reutlinger, A.; Gál, C.; Brandt, C.; Haberler, P.; Zuknik, K.-H.; Sedlmaier, T.; Shustov, B.; Sachkov, M.; Moisheev, A.; Kappelmann, N.; Barnstedt, J.; Werner, K.

2017-11-01

The World Space Observatory Ultraviolet (WSO/UV) is a multi-national project lead by the Russian Federal Space Agency (Roscosmos) with the objective of high performance observations in the ultraviolet range. The 1.7 m WSO/UV telescope feeds UV spectrometers and UV imagers. The UV spectrometers comprise two high resolution Echelle spectrographs for the 100 - 170 nm and 170 - 300 nm wavelength range and a long slit spectrograph for the 100 - 300 nm band. All three spectrometers represent individual instruments that are assembled and aligned separately. In order to save mass while maintaining high stiffness, the instruments are combined to a monoblock. Cesic has been selected to reduce CTE related distortions of the instruments. In contrast to aluminium, the stable structure of Cesic is significantly less sensitive to thermal gradients. No further mechanism for focus correction with high functional, technical and operational complexity and dedicated System costs are necessary. Using Cesic also relaxes the thermal control requirements of +/-5°C, which represents a considerable cost driver for the S/C design. The WUVS instrument is currently studied in the context of a phase B2 study by Kayser-Threde GmbH including a Structural Thermal Model (STM) for verification of thermal and mechanical loads, stability due to thermal distortions and Cesic manufacturing feasibility.

Creating Multisensory Environments: Practical Ideas for Teaching and Learning. David Fulton/Nasen

ERIC Educational Resources Information Center

Davies, Christopher

2011-01-01

Multi-sensory environments in the classroom provide a wealth of stimulating learning experiences for all young children whose senses are still under development. "Creating Multisensory Environments: Practical Ideas for Teaching and Learning" is a highly practical guide to low-cost cost, easy to assemble multi-sensory environments. With a…

Exploration of Force Transition in Stability Operations Using Multi-Agent Simulation

DTIC Science & Technology

2006-09-01

risk, mission failure risk, and time in the context of the operational threat environment. The Pythagoras Multi-Agent Simulation and Data Farming...NUMBER OF PAGES 173 14. SUBJECT TERMS Stability Operations, Peace Operations, Data Farming, Pythagoras , Agent- Based Model, Multi-Agent Simulation...the operational threat environment. The Pythagoras Multi-Agent Simulation and Data Farming techniques are used to investigate force-level

Advanced structural design for precision radial velocity instruments

NASA Astrophysics Data System (ADS)

Baldwin, Dan; Szentgyorgyi, Andrew; Barnes, Stuart; Bean, Jacob; Ben-Ami, Sagi; Brennan, Patricia; Budynkiewicz, Jamie; Chun, Moo-Young; Conroy, Charlie; Crane, Jeffrey D.; Epps, Harland; Evans, Ian; Evans, Janet; Foster, Jeff; Frebel, Anna; Gauron, Thomas; Guzman, Dani; Hare, Tyson; Jang, Bi-Ho; Jang, Jeong-Gyun; Jordan, Andres; Kim, Jihun; Kim, Kang-Min; Mendes de Oliveira, Claudia; Lopez-Morales, Mercedes; McCracken, Kenneth; McMuldroch, Stuart; Miller, Joseph; Mueller, Mark; Oh, Jae Sok; Ordway, Mark; Park, Byeong-Gon; Park, Chan; Park, Sung-Joon; Paxson, Charles; Phillips, David; Plummer, David; Podgorski, William; Seifahrt, Andreas; Stark, Daniel; Steiner, Joao; Uomoto, Alan; Walsworth, Ronald; Yu, Young-Sam

2016-07-01

The GMT-Consortium Large Earth Finder (G-CLEF) is an echelle spectrograph with precision radial velocity (PRV) capability that will be a first light instrument for the Giant Magellan Telescope (GMT). G-CLEF has a PRV precision goal of 40 cm/sec (10 cm/s for multiple measurements) to enable detection of Earth-like exoplanets in the habitable zones of sun-like stars1. This precision is a primary driver of G-CLEF's structural design. Extreme stability is necessary to minimize image motions at the CCD detectors. Minute changes in temperature, pressure, and acceleration environments cause structural deformations, inducing image motions which degrade PRV precision. The instrument's structural design will ensure that the PRV goal is achieved under the environments G-CLEF will be subjected to as installed on the GMT azimuth platform, including: Millikelvin (0.001 °K) thermal soaks and gradients 10 millibar changes in ambient pressure Changes in acceleration due to instrument tip/tilt and telescope slewing Carbon fiber/cyanate composite was selected for the optical bench structure in order to meet performance goals. Low coefficient of thermal expansion (CTE) and high stiffness-to-weight are key features of the composite optical bench design. Manufacturability and serviceability of the instrument are also drivers of the design. In this paper, we discuss analyses leading to technical choices made to minimize G-CLEF's sensitivity to changing environments. Finite element analysis (FEA) and image motion sensitivity studies were conducted to determine PRV performance under operational environments. We discuss the design of the optical bench structure to optimize stiffness-to-weight and minimize deformations due to inertial and pressure effects. We also discuss quasi-kinematic mounting of optical elements and assemblies, and optimization of these to ensure minimal image motion under thermal, pressure, and inertial loads expected during PRV observations.

Multi-task Gaussian process for imputing missing data in multi-trait and multi-environment trials.

PubMed

Hori, Tomoaki; Montcho, David; Agbangla, Clement; Ebana, Kaworu; Futakuchi, Koichi; Iwata, Hiroyoshi

2016-11-01

A method based on a multi-task Gaussian process using self-measuring similarity gave increased accuracy for imputing missing phenotypic data in multi-trait and multi-environment trials. Multi-environmental trial (MET) data often encounter the problem of missing data. Accurate imputation of missing data makes subsequent analysis more effective and the results easier to understand. Moreover, accurate imputation may help to reduce the cost of phenotyping for thinned-out lines tested in METs. METs are generally performed for multiple traits that are correlated to each other. Correlation among traits can be useful information for imputation, but single-trait-based methods cannot utilize information shared by traits that are correlated. In this paper, we propose imputation methods based on a multi-task Gaussian process (MTGP) using self-measuring similarity kernels reflecting relationships among traits, genotypes, and environments. This framework allows us to use genetic correlation among multi-trait multi-environment data and also to combine MET data and marker genotype data. We compared the accuracy of three MTGP methods and iterative regularized PCA using rice MET data. Two scenarios for the generation of missing data at various missing rates were considered. The MTGP performed a better imputation accuracy than regularized PCA, especially at high missing rates. Under the 'uniform' scenario, in which missing data arise randomly, inclusion of marker genotype data in the imputation increased the imputation accuracy at high missing rates. Under the 'fiber' scenario, in which missing data arise in all traits for some combinations between genotypes and environments, the inclusion of marker genotype data decreased the imputation accuracy for most traits while increasing the accuracy in a few traits remarkably. The proposed methods will be useful for solving the missing data problem in MET data.

Heterogeneous variances in multi-environment yield trials for corn hybrids

USDA-ARS?s Scientific Manuscript database

Recent developments in statistics and computing have enabled much greater levels of complexity in statistical models of multi-environment yield trial data. One particular feature of interest to breeders is simultaneously modeling heterogeneity of variances among environments and cultivars. Our obj...

A Qualitative Case Study Approach To Examine Information Resources Management. (Utilisation d'une Approche Qualitative par Methode de cas pour Etudier la Gestion des Ressources D'information).

ERIC Educational Resources Information Center

Bergeron, Pierrette

1997-01-01

Illustrates how a qualitative approach was used to study the complex and poorly defined concept of information resources management. Explains the general approach to data collection, its advantages and limitations, and the process used to analyze the data. Presents results, along with lessons learned through using method. (Author/AEF)

Les Representations Sociales de la Ville Chez les Ecoliers de Deux Villes Europeennes, d'Arles et de Sparte: Une Approche Comparative.

ERIC Educational Resources Information Center

Zafeirakou, Aegli

1998-01-01

In an exchange program, 11- and 12-year olds from Arles (France) (n=25) and Sparta (Greece) (n=27) visited each other's cities and explored the culture and history. This study explores the ways they conceptualized the cultural patrimony of both cities through student drawings. The exchange created opportunities for dialog about European culture.…

Learning from Experience: A New Approach for Teacher Upgrading = Apprendre par l'experience: Une nouvelle approche en matiere de formation et de perfectionnement des enseignants. Notes, Comments...No. 190.

ERIC Educational Resources Information Center

Barkatoolah, Amina B. S.

Two of Unesco's major education programs, the universalizaation of basic education and literacy education, have emphasized the need for teachers trained in their particular disciplines and pedagogical techniques. Developing countries, faced with a shortage of qualified teachers, have realized that they cannot rely solely on the formal education…

IFLA General Conference 1991. Division of Regional Activities: Section of Africa; Section of Asia and Oceania; Section of Latin America and the Carribean. Booklet 8.

ERIC Educational Resources Information Center

International Federation of Library Associations and Institutions, The Hague (Netherlands).

The six papers in this collection were presented at three sections of the Division of Regional Activities: (1) "A la recherche d'Approches adaptees aux Besoins en Documentation des Africains (In Search of an Approach Adapted to the Information Needs of Africans)" (Touria Temsamani Haji, Morocco); (2) "People's Libraries: An African…

QUELS FUTURS TRAITEMENTS POUR LA DEPENDANCE AU TABAC ET AU CANNABIS?

PubMed Central

LE FOLL, Bernard; JUSTINOVA, Zuzana; TANDA, Gianlugi; GOLDBERG, Steven R.

2009-01-01

RESUME Plus de trois millions de morts sont attribués au tabagisme dans le monde par an, et l’usage de tabac est en progression dans les pays en voie de développement. L’usage de tabac est donc une des rares causes de mortalité qui augmente, avec une prévision de plus de 10 millions de morts par an dans 30–40 ans. Le cannabis ou marijuana est la drogue illicite la plus consommée dans le monde et il n’y a actuellement pas de traitement disponible. Bien que les systèmes dopaminergiques jouent un rôle central dans les effets renforçants des drogues, d’autres systèmes sont impliqués. Nous présentons ici des résultats récents obtenus avec des antagonistes des récepteurs cannabinoides CB1, des récepteurs D3 de la dopamine et des récepteurs opioïdes. Ces antagonistes qui modulent de façon directe ou indirecte la transmission dopaminergique cérébrale représentent des approches prometteuses pour le traitement du tabagisme ou de la dépendance au cannabis. Ces approches sont à valider dans des essais cliniques. PMID:18663981

Implementation of a Multi-Robot Coverage Algorithm on a Two-Dimensional, Grid-Based Environment

DTIC Science & Technology

2017-06-01

two planar laser range finders with a 180-degree field of view , color camera, vision beacons, and wireless communicator. In their system, the robots...Master’s thesis 4. TITLE AND SUBTITLE IMPLEMENTATION OF A MULTI -ROBOT COVERAGE ALGORITHM ON A TWO -DIMENSIONAL, GRID-BASED ENVIRONMENT 5. FUNDING NUMBERS...path planning coverage algorithm for a multi -robot system in a two -dimensional, grid-based environment. We assess the applicability of a topology

An Improvement of Robust Biometrics-Based Authentication and Key Agreement Scheme for Multi-Server Environments Using Smart Cards

PubMed Central

Moon, Jongho; Choi, Younsung; Jung, Jaewook; Won, Dongho

2015-01-01

In multi-server environments, user authentication is a very important issue because it provides the authorization that enables users to access their data and services; furthermore, remote user authentication schemes for multi-server environments have solved the problem that has arisen from user’s management of different identities and passwords. For this reason, numerous user authentication schemes that are designed for multi-server environments have been proposed over recent years. In 2015, Lu et al. improved upon Mishra et al.’s scheme, claiming that their remote user authentication scheme is more secure and practical; however, we found that Lu et al.’s scheme is still insecure and incorrect. In this paper, we demonstrate that Lu et al.’s scheme is vulnerable to outsider attack and user impersonation attack, and we propose a new biometrics-based scheme for authentication and key agreement that can be used in multi-server environments; then, we show that our proposed scheme is more secure and supports the required security properties. PMID:26709702

'Putting it on the table': direct-manipulative interaction and multi-user display technologies for semi-immersive environments and augmented reality applications.

PubMed

Encarnação, L Miguel; Bimber, Oliver

2002-01-01

Collaborative virtual environments for diagnosis and treatment planning are increasingly gaining importance in our global society. Virtual and Augmented Reality approaches promised to provide valuable means for the involved interactive data analysis, but the underlying technologies still create a cumbersome work environment that is inadequate for clinical employment. This paper addresses two of the shortcomings of such technology: Intuitive interaction with multi-dimensional data in immersive and semi-immersive environments as well as stereoscopic multi-user displays combining the advantages of Virtual and Augmented Reality technology.

Extremely metal-deficient red giants. IV - Equivalent widths for 36 halo giants

NASA Technical Reports Server (NTRS)

Luck, R. E.; Bond, H. E.

1985-01-01

Further work on a study of 36 metal-poor field red giants is reported. Chemical abundances previously determined were based on model stellar atmosphere analyses of equivalent widths from photographic image-tube echelle spectrograms obtained with with 4-m reflectors at Kitt Peak and Cerro Tololo. A tabulation of the equivalent-width data (a total of 18, 275 equivalent widths) is presented.

Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph and FORS2 spectroscopy of the GRB 081008 afterglow

NASA Astrophysics Data System (ADS)

D'Elia, V.; Campana, S.; Covino, S.; D'Avanzo, P.; Piranomonte, S.; Tagliaferri, G.

2011-11-01

We aim at studying the gamma-ray burst (GRB), GRB 081008, environment by analysing the spectra of its optical afterglow. Ultraviolet and Visual Echelle Spectrograph/Very Large Telescope (UVES/VLT) high-resolution spectroscopy of GRB 081008 was secured ˜5 h after the Swift-BAT trigger. Our data set also comprises three VLT/FORS2 nearly simultaneous spectra of the same source. The availability of nearly simultaneous high- and low-resolution spectra for a GRB afterglow is an extremely rare event. The GRB-damped Lyman α system at z= 1.9683 shows that the interstellar medium (ISM) of the host galaxy is constituted by at least three components which contribute to the line profiles. Component I is the redmost one, and is 20 and 78 km s-1 redward components II and III, respectively. We detect several ground state and excited absorption features in components I and II. These features have been used to compute the distances between the GRB and the absorbers. Component I is found to be 52 ± 6 pc away from the GRB, while component II presents few excited transitions and its distance is 200+60- 80 pc. Component III only features a few, low-ionization and saturated lines suggesting that it is even farther from the GRB. Component I represents the closest absorber ever detected near a GRB. This (relatively) low distance can possibly be a consequence of a dense GRB environment, which prevents the GRB prompt/afterglow emission to strongly affect the ISM up to higher distances. The hydrogen column density associated with GRB 081008 is log NH/cm-2= 21.11 ± 0.10, and the metallicity of the host galaxy is in the range of [X/H] =-1.29 to -0.52. In particular, we found [Fe/H] =-1.19 ± 0.11 and [Zn/H] =-0.52 ± 0.11 with respect to solar values. This discrepancy can be explained by the presence of dust in the GRB ISM, given the opposite refractory properties of iron and zinc. By deriving the depletion pattern for GRB 081008, we find the optical extinction in the visual band to be AV˜ 0.19 mag. The curve-of-growth analysis applied to the FORS2 spectra brings column densities consistent at the 3σ level to that evaluated from the UVES data using the line-fitting procedure. This reflects the low saturation of the detected GRB 081008 absorption features. Based on observations collected at the European Southern Observatory, ESO, the VLT/Kueyen telescope, Paranal, Chile, in the framework of the programme 082-0755.

40 CFR 59.506 - How do I demonstrate compliance if I manufacture multi-component kits?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 5 2010-07-01 2010-07-01 false How do I demonstrate compliance if I manufacture multi-component kits? 59.506 Section 59.506 Protection of Environment ENVIRONMENTAL PROTECTION... § 59.506 How do I demonstrate compliance if I manufacture multi-component kits? (a) If you manufacture...

Approche statistique de l'aridification de l'Afrique de l'Ouest

NASA Astrophysics Data System (ADS)

Hubert, Pierre; Carbonnel, Jean-Pierre

1987-11-01

The statistical study of 42 rainfall series from Niger to Senegal, the length of which is between 37 and 97 years, points out the nonstationarity of these series and suggests a climatic jump about 1969-1970. An integrated autoregressive model (ARIMA) of order ( p, 1, 0) can be fitted to most of these series but such a model remains useless for operational purposes. Some climatological, meteorological and hydrological consequences are discussed.

The Complexity Construct in Political Psychology: Personological and Cognitive Approaches

DTIC Science & Technology

2010-02-01

raisonnement et du processus de prise de décision conciliant, ouvert et reposant sur l’information. Les deux approches font appel à une analyse de...positions in order to make room for the next generation. The elderly must resign themselves to “let go” of their family domination and employment in... employment positions. This would only contribute to an adversarial relationship (albeit reversed), where resources are still not distributed with social

L'integration de la grammaire dans une approche interactive/experientielle en francais de base (The Integration of Grammar in an Interactive/Experiential Approach in Core French).

ERIC Educational Resources Information Center

Jean, Gladys

1999-01-01

Examines the integration of grammar into second-language instruction, specifically in core French courses in Canada. A brief overview of studies on this topic in different settings is followed by an attempt to demonstrate how the limited results of available studies can offer a starting point for finding solutions to the problems of integrating…

Apprentissage de l'expression orale en autonomie. Implications de l'approche fonctionelle (Learning Oral Expression in Independent Study. Implications of the Functional Approach). Melanges pedagogiques.

ERIC Educational Resources Information Center

Abe, D.; And Others

Within the CRAPEL autonomous learning scheme, modular material is being developed for communicative oral expression. The purpose of this material is twofold: (1) to enable the learner to define his or her own needs in communicative terms, that is, to analyse a situation in terms of communicative acts needed in a given situation, the relationships…

Multi-Robot, Multi-Target Particle Swarm Optimization Search in Noisy Wireless Environments

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

Kurt Derr; Milos Manic

Multiple small robots (swarms) can work together using Particle Swarm Optimization (PSO) to perform tasks that are difficult or impossible for a single robot to accomplish. The problem considered in this paper is exploration of an unknown environment with the goal of finding a target(s) at an unknown location(s) using multiple small mobile robots. This work demonstrates the use of a distributed PSO algorithm with a novel adaptive RSS weighting factor to guide robots for locating target(s) in high risk environments. The approach was developed and analyzed on multiple robot single and multiple target search. The approach was further enhancedmore » by the multi-robot-multi-target search in noisy environments. The experimental results demonstrated how the availability of radio frequency signal can significantly affect robot search time to reach a target.« less

Multi-AUV Target Search Based on Bioinspired Neurodynamics Model in 3-D Underwater Environments.

PubMed

Cao, Xiang; Zhu, Daqi; Yang, Simon X

2016-11-01

Target search in 3-D underwater environments is a challenge in multiple autonomous underwater vehicles (multi-AUVs) exploration. This paper focuses on an effective strategy for multi-AUV target search in the 3-D underwater environments with obstacles. First, the Dempster-Shafer theory of evidence is applied to extract information of environment from the sonar data to build a grid map of the underwater environments. Second, a topologically organized bioinspired neurodynamics model based on the grid map is constructed to represent the dynamic environment. The target globally attracts the AUVs through the dynamic neural activity landscape of the model, while the obstacles locally push the AUVs away to avoid collision. Finally, the AUVs plan their search path to the targets autonomously by a steepest gradient descent rule. The proposed algorithm deals with various situations, such as static targets search, dynamic targets search, and one or several AUVs break down in the 3-D underwater environments with obstacles. The simulation results show that the proposed algorithm is capable of guiding multi-AUV to achieve search task of multiple targets with higher efficiency and adaptability compared with other algorithms.

Characterisation of Fibre Reinforced Titanium Matrix Composites. (La Caracterisation des Materiaux Composites a Matrice de Titane Renforces par Fibres)

DTIC Science & Technology

1994-02-01

devait servir de forum pour un 6change d’informations sur ce sujet important. Dans ce cas. [a caracterisation se ref~re A l’analyse du comportement des...phases de d~veloppement et de mise a l’echelle. mais aussi aux activites de caracterisation et de demonstration des composants. Dans le cas des materiaux

HPF: The Habitable Zone Planet Finder at the Hobby-Eberly Telescope

NASA Astrophysics Data System (ADS)

Wright, Jason T.; Mahadevan, Suvrath; Hearty, Fred; Monson, Andy; Stefansson, Gudmundur; Ramsey, Larry; Ninan, Joe; Bender, Chad; Kaplan, Kyle; Roy, Arpita; Terrien, Ryan; Robertson, Paul; Halverson, Sam; Schwab, Christian; Kanodia, Shubham

2018-01-01

The Habitable Zone Planet Finder (HPF) is an ultra-stable NIR (ZYJ) high resolution echelle spectrograph on the 10-m Hobby-Eberly Telescope capable of 1-3 m/s Doppler velocimetry on nearby late M dwarfs (M4-M9). This precision is sufficient to detect terrestrial planets in the Habitable Zones of these relatively unexplored stars. Here we present its capabilities and early commissioning results.

A search for lithium in Pleiades brown dwarf candidates using the Keck hires echelle

NASA Technical Reports Server (NTRS)

Marcy, Geoffrey W.; Basri, Gibor; Graham, James R.

1994-01-01

We report Keck Observatory high-resolution echelle spectra of lithium at 670.8 nm in two of the lowest luminosity brown dwarf candidates in the Pleiades. These objects have estimated masses of 0.055 to 0.059 solar mass from their location on a color-magnitude diagram relative to theoretical isochrones. Stellar interior models predict that Li has not burned in them. However, we find no evidence of the Li line, at limits 100 to 1000 times below the initial abundance. This indicates that Li has in fact been depleted, presumably by nuclear processing as occurs in Pleiades stars. Interior models suggest that such large Li depletion occurs only for objects with M greater than 0.09 solar mass at the age of the Pleiades. Thus, it is unlikely that the candidates are brown dwarfs. The brown dwarf candidates present a conflict: either they have masses greater than suggested from their placement on the H-R diagram, or they do have the very low suggested masses but are nonetheless capable of destroying Li, in only 70 Myr. Until this dilemma is resolved, the photometric identification of brown dwarfs will remain difficult. Resolution may reside in higher T(sub eff) derived from optical and IR colors or in lower T(sub eff) in the interior models.

WILSON-BAPPU EFFECT: EXTENDED TO SURFACE GRAVITY

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

Park, Sunkyung; Kang, Wonseok; Lee, Jeong-Eun

2013-10-01

In 1957, Wilson and Bappu found a tight correlation between the stellar absolute visual magnitude (M{sub V} ) and the width of the Ca II K emission line for late-type stars. Here, we revisit the Wilson-Bappu relationship (WBR) to claim that the WBR can be an excellent indicator of stellar surface gravity of late-type stars as well as a distance indicator. We have measured the width (W) of the Ca II K emission line in high-resolution spectra of 125 late-type stars obtained with the Bohyunsan Optical Echelle Spectrograph and adopted from the Ultraviolet and Visual Echelle Spectrograph archive. Based onmore » our measurement of the emission line width (W), we have obtained a WBR of M{sub V} = 33.76 - 18.08 log W. In order to extend the WBR to being a surface gravity indicator, stellar atmospheric parameters such as effective temperature (T{sub eff}), surface gravity (log g), metallicity ([Fe/H]), and micro-turbulence ({xi}{sub tur}) have been derived from self-consistent detailed analysis using the Kurucz stellar atmospheric model and the abundance analysis code, MOOG. Using these stellar parameters and log W, we found that log g = -5.85 log W+9.97 log T{sub eff} - 23.48 for late-type stars.« less

Updates on the Performance and Calibration of HST/STIS

NASA Astrophysics Data System (ADS)

Lockwood, Sean A.; Monroe, TalaWanda R.; Ogaz, Sara; Branton, Doug; Carlberg, Joleen K.; Debes, John H.; Jedrzejewski, Robert I.; Proffitt, Charles R.; Riley, Allyssa; Sohn, Sangmo Tony; Sonnentrucker, Paule; Walborn, Nolan R.; Welty, Daniel

2018-06-01

The Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) has been in orbit for 21 years and continues to produce high quality scientific results using a diverse complement of operating modes. These include spatially resolved spectroscopy in the UV and optical, high spatial resolution echelle spectroscopy in the UV, and solar-blind imaging in the UV. In addition, STIS possesses unique visible-light coronagraphic modes that keep the instrument at the forefront of exoplanet and debris-disk research. As the instrument's characteristics evolve over its lifetime, the instrument team at the Space Telescope Science Institute monitors its performance and works towards improving the quality of its data products. Here we present updates on the status of the STIS CCD and FUV & NUV MAMA detectors, as well as changes to the CalSTIS reduction pipeline. We also discuss progress toward the recalibration of the E140M/1425 echelle mode. The E140M grating blaze function shapes have changed since flux calibration was carried out following SM4, which limits the relative photometric flux accuracy of some spectral orders up to 5-10% at the edges. In Cycle 25 a special calibration program was executed to obtain updated sensitivity curves for the E140M/1425 setting.

VizieR Online Data Catalog: The G+M eclipsing binary V530 Orionis photometry (Torres+, 2014)

NASA Astrophysics Data System (ADS)

Torres, G.; Lacy, C. H. S.; Pavlovski, K.; Feiden, G. A.; Sabby, J. A.; Bruntt, H.; Clausen, J. V.

2017-08-01

V530 Ori was monitored spectroscopically with three different instruments over a period of more than 17 yr. Observations began at the Harvard-Smithsonian Center for Astrophysics (CfA) in 1996 June with a Cassegrain-mounted echelle spectrograph ("Digital Speedometer", DS; Latham 1992ASPC...32..110L) attached to the 1.5 m Tillinghast reflector at the F. L. Whipple Observatory (Mount Hopkins, AZ). We gathered a further 30 spectra of V530 Ori at the Kitt Peak National Observatory (KPNO) from 1999 March to 2001 January, using the coude-feed telescope and the coude spectrometer. Finally, 41 additional observations were obtained at the CfA from 2009 November to 2014 March with the Tillinghast Reflector Echelle Spectrograph (TRES; Furesz 2008, PhD thesis , Univ. Szeged, Hungary) on the 1.5 m telescope mentioned earlier. Two sets of V-band images of V530 Ori were obtained with independent robotic telescopes operating at the University of Arkansas (URSA WebScope) and near Silver City, NM (NFO WebScope) from 2001 January to 2012 February. Differential photometric measurements of V530 Ori were also gathered with the Stromgren Automatic Telescope at ESO (La Silla, Chile), during several campaigns from 2001 January to 2006 February. (5 data files).

Prise en charge des troubles de consommation d’opioïdes en première ligne

PubMed Central

Srivastava, Anita; Kahan, Meldon; Nader, Maya

2017-01-01

Résumé Objectif Conseiller les médecins quant aux options thérapeutiques à recommander à des populations précises de patients : approche axée sur l’abstinence, traitement d’entretien par la buprénorphine-naloxone ou traitement d’entretien par la méthadone. Sources d’information Une recherche sur PubMed a été effectuée, et on a relevé dans les publications les données sur l’efficacité, l’innocuité et le profil d’effets indésirables de l’approche axée sur l’abstinence, du traitement par la buprénorphine-naloxone et du traitement par la méthadone. Les études d’observation et interventionnelles ont été incluses. Message principal La méthadone et la buprénorphine-naloxone sont substantiellement plus efficaces que l’approche axée sur l’abstinence. La méthadone présente un taux de rétention plus élevé que la buprénorphine-naloxone, alors que la buprénorphine-naloxone présente un risque plus faible de surdose. Les médecins devraient recommander le traitement par la méthadone ou la buprénorphine-naloxone plutôt que l’approche axée sur l’abstinence, et ce, à tous les groupes de patients (données de niveau I). La méthadone est préférable à la buprénorphine-naloxone chez les patients qui présentent un risque élevé d’abandon, comme les usagers d’opioïdes par injection (données de niveau I). Les jeunes et les femmes enceintes qui font usage d’opioïdes par injection devraient aussi recevoir la méthadone d’abord (données de niveau III). Si la buprénorphine-naloxone est prescrite en premier, il faut faire passer rapidement le patient à la méthadone si les symptômes de sevrage, les fortes envies ou la consommation d’opioïdes persistent malgré une dose optimale de buprénorphine-naloxone (données de niveau II). La buprénorphine-naloxone est recommandée chez les usagers d’opioïdes sur ordonnance par voie orale socialement stables, surtout s’ils ont un emploi ou si leurs obligations familiales les empêchent de se rendre à la pharmacie tous les jours, s’ils ont une affection médicale ou psychiatrique exigeant des soins réguliers de première ligne (données de niveau IV), ou encore si leur emploi exige une fonction cognitive ou un rendement psychomoteur élevés (données de niveau III). La buprénorphine-naloxone est aussi recommandée chez les patients qui présentent un risque élevé de toxicité à la méthadone, tels que les personnes âgées, les personnes qui prennent de fortes doses de benzodiazépines ou d’autres sédatifs, les gros buveurs, les personnes dont la tolérance aux opioïdes est faible et les personnes à risque de prolongement de l’intervalle QT (données de niveau III). Conclusion Il faut tenir compte des caractéristiques et des préférences individuelles des patients lors de la sélection d’un traitement de première intention par un agoniste des opioïdes. Chez les patients qui présentent un risque élevé d’abandon (adolescents et patients socialement instables), la rétention en traitement doit avoir préséance sur les autres considérations cliniques. Chez les patients qui présentent un risque élevé de toxicité (comme les usagers abusifs d’alcool ou de benzodiazépines), la sécurité a sans doute préséance. Ce qu’il importe le plus de considérer toutefois, c’est que le traitement par un agoniste des opioïdes est beaucoup plus efficace que l’approche axée sur l’abstinence. PMID:28292811

Applications of Multi-Agent Technology to Power Systems

NASA Astrophysics Data System (ADS)

Nagata, Takeshi

Currently, agents are focus of intense on many sub-fields of computer science and artificial intelligence. Agents are being used in an increasingly wide variety of applications. Many important computing applications such as planning, process control, communication networks and concurrent systems will benefit from using multi-agent system approach. A multi-agent system is a structure given by an environment together with a set of artificial agents capable to act on this environment. Multi-agent models are oriented towards interactions, collaborative phenomena, and autonomy. This article presents the applications of multi-agent technology to the power systems.

Combining engineered cell-sensors with multi-agent systems to realize smart environment

NASA Astrophysics Data System (ADS)

Chen, Mei

2013-03-01

The connection of everything in a sensory and an intelligent way is a pursuit in smart environment. This paper introduces the engineered cell-sensors into the multi-agent systems to realize the smart environment. The seamless interface with the natural environment and strong information-processing ability of cell with the achievements of synthetic biology make the construction of engineered cell-sensors possible. However, the engineered cell-sensors are only simple-functional and unreliable computational entities. Therefore how to combine engineered cell-sensors with digital device is a key problem in order to realize the smart environment. We give the abstract structure and interaction modes of the engineered cell-sensors in order to introduce engineered cell-sensors into multi-agent systems. We believe that the introduction of engineered cell-sensors will push forward the development of the smart environment.

Caracterisation des proprietes acoustiques des materiaux poreux a cellules ouvertes et a matrice rigide ou souple

NASA Astrophysics Data System (ADS)

Salissou, Yacoubou

L'objectif global vise par les travaux de cette these est d'ameliorer la caracterisation des proprietes macroscopiques des materiaux poreux a structure rigide ou souple par des approches inverses et indirectes basees sur des mesures acoustiques faites en tube d'impedance. La precision des approches inverses et indirectes utilisees aujourd'hui est principalement limitee par la qualite des mesures acoustiques obtenues en tube d'impedance. En consequence, cette these se penche sur quatre problemes qui aideront a l'atteinte de l'objectif global precite. Le premier probleme porte sur une caracterisation precise de la porosite ouverte des materiaux poreux. Cette propriete en est une de passage permettant de lier la mesure des proprietes dynamiques acoustiques d'un materiau poreux aux proprietes effectives de sa phase fluide decrite par les modeles semi-phenomenologiques. Le deuxieme probleme traite de l'hypothese de symetrie des materiaux poreux selon leur epaisseur ou un index et un critere sont proposes pour quantifier l'asymetrie d'un materiau. Cette hypothese est souvent source d'imprecision des methodes de caracterisation inverses et indirectes en tube d'impedance. Le critere d'asymetrie propose permet ainsi de s'assurer de l'applicabilite et de la precision de ces methodes pour un materiau donne. Le troisieme probleme vise a mieux comprendre le probleme de transmission sonore en tube d'impedance en presentant pour la premiere fois un developpement exact du probleme par decomposition d'ondes. Ce developpement permet d'etablir clairement les limites des nombreuses methodes existantes basees sur des tubes de transmission a 2, 3 ou 4 microphones. La meilleure comprehension de ce probleme de transmission est importante puisque c'est par ce type de mesures que des methodes permettent d'extraire successivement la matrice de transfert d'un materiau poreux et ses proprietes dynamiques intrinseques comme son impedance caracteristique et son nombre d'onde complexe. Enfin, le quatrieme probleme porte sur le developpement d'une nouvelle methode de transmission exacte a 3 microphones applicable a des materiaux ou systemes symetriques ou non. Dans le cas symetrique, on montre que cette approche permet une nette amelioration de la caracterisation des proprietes dynamiques intrinseques d'un materiau. Mots cles. materiaux poreux, tube d'impedance, transmission sonore, absorption sonore, impedance acoustique, symetrie, porosite, matrice de transfert.

Managing Cognitive Load in Educational Multi-User Virtual Environments: Reflection on Design Practice

ERIC Educational Resources Information Center

Nelson, Brian C.; Erlandson, Benjamin E.

2008-01-01

In this paper, we explore how the application of multimedia design principles may inform the development of educational multi-user virtual environments (MUVEs). We look at design principles that have been shown to help learners manage cognitive load within multimedia environments and conduct a conjectural analysis of the extent to which such…

Socialisation for Learning at a Distance in a 3-D Multi-User Virtual Environment

ERIC Educational Resources Information Center

Edirisingha, Palitha; Nie, Ming; Pluciennik, Mark; Young, Ruth

2009-01-01

This paper reports findings of a pilot study that examined the pedagogical potential of "Second Life" (SL), a popular three-dimensional multi-user virtual environment (3-D MUVE) developed by the Linden Lab. The study is part of a 1-year research and development project titled "Modelling of Secondlife Environments"…

Numerical simulation of steady cavitating flow of viscous fluid in a Francis hydroturbine

NASA Astrophysics Data System (ADS)

Panov, L. V.; Chirkov, D. V.; Cherny, S. G.; Pylev, I. M.; Sotnikov, A. A.

2012-09-01

Numerical technique was developed for simulation of cavitating flows through the flow passage of a hydraulic turbine. The technique is based on solution of steady 3D Navier—Stokes equations with a liquid phase transfer equation. The approch for setting boundary conditions meeting the requirements of cavitation testing standard was suggested. Four different models of evaporation and condensation were compared. Numerical simulations for turbines of different specific speed were compared with experiment.

Trust Repair between a Military Organization and a Local Population: A Pilot Study

DTIC Science & Technology

2011-02-01

l’aspect « public » du paradigme IIMP, une approche relativement nouvelle pour un grand nombre de militaires et le plus grand des défis pour les...questionnaires were reviewed and approved by the DRDC Human Research Ethics Committee (HREC) and all participants received remuneration according to DRDC...Form. The Human Research Ethics Committee (HREC) of Defence Research and Development Canada (DRDC) has approved this study (L-701A). If you have

Circadian Countermeasures in the High Arctic during Summer

DTIC Science & Technology

2014-11-01

qualité du sommeil, comparativement à l’hiver (Paul, M. A., R.J. Love, A.M. Hawton et coll., Melatonin production, sleep patterns and modeled... Comparativement aux conditions de 2012, le commandant (cmdt) et l’adjudant de la station (adj Sta) en poste en juin 2014 ont adopté une approche prudente au...intervals under dim light conditions (᝺ lux; [15-18]). The time of the first sample that exceeds a prescribed threshold is designated as DLMO. In this

VizieR Online Data Catalog: Spectroscopic and photometric properties of Tombaugh 1 (Sales+, 2016)

NASA Astrophysics Data System (ADS)

Sales Silva, J. V.; Carraro, G.; Anthony-Twarog, B. J.; Moni Bidin, C.; Costa, E.; Twarog, B. A.

2018-03-01

Photometry for Tombaugh 1 was secured in 2010 December during a five-night run using the Cerro Tololo Inter-American Observatory 1.0 m telescope operated by the SMARTS consortium (http://www.astro.yale.edu/smarts). The telescope is equipped with an STA 4064x4064 CCD camera (http://www.astronomy.ohio-state.edu/Y4KCam/detector) with 15 μm pixels, yielding a scale of 0.289"/pixel and a field of view (FOV) of 20'x20' at the Cassegrain focus of the telescope. Over the night of 2010 January 5, we observed 10 potential cluster stars (nine clump stars and one Cepheid; see Section 4.1) with the Inamori-Magellan Areal Camera & Spectrograph (IMACS; Dressler et al. 2006SPIE.6269E..0FD) attached to the Magellan telescope (6.5 m) located at Las Campanas, Chile. The spectra were obtained using the Multi-Object Echelle (MOE) mode with two exposures, one of 900 s and the other of 1200 s. Our spectra have a resolution of R~20000, while the spectral coverage depends on the location of the star on the multislit mask, but it generally goes from 4200 to 9100 Å. The detector consists of a mosaic with eight CCDs with gaps of about 0.93 mm between the CCDs, causing small gaps in stellar spectra. (7 data files).

Fast analysis of wood preservers using laser induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Uhl, A.; Loebe, K.; Kreuchwig, L.

2001-06-01

Laser-induced breakdown spectroscopy (LIBS) is used for the investigation of wood preservers in timber and in furniture. Both experiments in laboratory and practical applications in recycling facilities and on a building site prove the new possibilities for the fast detection of harmful agents in wood. A commercial system was developed for mobile laser-plasma-analysis as well as for industrial use in sorting plants. The universal measuring principle in combination with an Echelle optics permits real simultaneous multi-element-analysis in the range of 200-780 nm with a resolution of a few picometers. It enables the user to detect main and trace elements in wood within a few seconds, nearly independent of the matrix, knowing that different kinds of wood show an equal elemental composition. Sample preparation is not required. The quantitative analysis of inorganic wood preservers (containing, e.g. Cu, Cr, B, As, Pb, Hg) has been performed exactly using carbon as reference element. It can be shown that the detection limits for heavy metals in wood are in the ppm-range. Additional information is given concerning the quantitative analysis. Statistical data, e.g. the standard deviation (S.D.), were determined and calibration curves were used for each particular element. A comparison between ICP-AES and LIBS is given using depth profile correction factors regarding the different penetration depths with respect to the different volumes in wood analyzed by both analytical methods.

Design of the TMT Mid-Infrared Echelle: Science Drivers and Design Overview

DTIC Science & Technology

2006-01-01

plausibility of an extra-terrestrial origin for the prebiotic compounds that led to the emergence of life on Earth. MIRES imaging of debris disks will...explore mechanisms by which water and prebiotic organic compounds may have been delivered to planetary surfaces. These studies will be highly synergistic...that are precursors to complex prebiotic compounds. The high sensitivity also allows the exploration of a wider range of wavelengths, including those

VizieR Online Data Catalog: Echelle spectra of 10 bright asteroids (Zwitter+, 2007)

NASA Astrophysics Data System (ADS)

Zwitter, T.; Mignard, F.; Crifo, F.

2006-10-01

Table 5 gives observed spectra of twilight and asteroids rebinned to the same wavelength bins, continuum normalized and Doppler shifted to zero radial velocity. Asteroid spectra of 1 Ceres, 2 Pallas, 3 Juno, 4 Vesta, 9 Metis, 21 Lutetia, 27 Euterpe, 40 Harmonia, 49 Pales, and 80 Sappho are given. Spectra of observed twilight sky and of a theoretical Kurucz Solar model are added for comparison. (1 data file).

GHRS Ech-B Wavelength Monitor -- Cycle 4

NASA Astrophysics Data System (ADS)

Soderblom, David

1994-01-01

This proposal defines the spectral lamp test for Echelle B. It is an internal test which makes measurements of the wavelength lamp SC2. It calibrates the carrousel function, Y deflections, resolving power, sensitivity, and scattered light. The wavelength calibration dispersion constants will be updated in the PODPS calibration data base. It will be run every 4 months. The wavelengths may be out of range according to PEPSI or TRANS. Please ignore the errors.

Proposed design class of grazing incidence echelle spectrometers - Critical analysis and reevaluation

NASA Technical Reports Server (NTRS)

Hettrick, M. C.; Jelinsky, P.; Bowyer, S.; Malina, R. F.

1984-01-01

The class of miltibounce grazing spectrometers proposed by Cash (1982) and by McClintock and Cash (1982) is analyzed, and performance values significantly lower than asserted by these authors are found. Ray tracing calculations used to examine the design parameters given in the above papers are reported, as is the efficiency which results from use of accepted reflectance data. Several schemes which can improve some of the performance parameters are indicated.

The Use of a UNIX-Based Workstation in the Information Systems Laboratory

DTIC Science & Technology

1989-03-01

system. The conclusions of the research and the resulting recommendations are presented in Chapter III. These recommendations include how to manage...required to run the program on a new system, these should not be significant changes. 2. Processing Environment The UNIX processing environment is...interactive with multi-tasking and multi-user capabilities. Multi-tasking refers to the fact that many programs can be run concurrently. This capability

EDMC: An enhanced distributed multi-channel anti-collision algorithm for RFID reader system

NASA Astrophysics Data System (ADS)

Zhang, YuJing; Cui, Yinghua

2017-05-01

In this paper, we proposes an enhanced distributed multi-channel reader anti-collision algorithm for RFID environments which is based on the distributed multi-channel reader anti-collision algorithm for RFID environments (called DiMCA). We proposes a monitor method to decide whether reader receive the latest control news after it selected the data channel. The simulation result shows that it improves interrogation delay.

Conception, elaboration et mise a l'essai d'un simulateur interactif permettant une approche modelisante: Application aux lois de la genetique mendelienne

NASA Astrophysics Data System (ADS)

Lasri, Abdel-Halim

Dans cette recherche-developpement, nous avons concu, developpe et mis a l'essai un simulateur interactif pour favoriser l'apprentissage des lois probabilistes impliqees dans la genetique mendelienne. Cet environnement informatise devra permettre aux etudiants de mener des experiences simulees, utilisant les statistiques et les probebilites comme outils mathematiques pour modeliser le phenomene de la transmission des caracteres hereditaires. L'approche didactique est essentiellement orientee vers l'utilisation des methodes quantitatives impliquees dans l'experimentation des facteurs hereditaires. En incorporant au simulateur le principe de la "Lunette cognitive" de Nonnon (1986), l'etudiant fut place dans une situation ou il a pu synchroniser la perception de la representation iconique (concrete) et symbolique (abstraite) des lois probabilistes de Mendel. A l'aide de cet environnement, nous avons amene l'etudiant a identifier le(s) caractere(s) hereditaire(s) des parents a croiser, a predire les frequences phenotypiques probables de la descendance issue du croisement, a observer les resultats statistiques et leur fluctuation au niveau de l'histogramme des frequences, a comparer ces resultats aux predictions anticipees, a interpreter les donnees et a selectionner en consequence d'autres experiences a realiser. Les etapes de l'approche inductive sont privilegiees du debut a la fin des activites proposees. L'elaboration, du simulateur et des documents d'accompagnement, a ete concue a partir d'une vingtaine de principes directeurs et d'un modele d'action. Ces principes directeurs et le modele d'action decoulent de considerations theoriques psychologiques, didactiques et technologiques. La recherche decrit la structure des differentes parties composant le simulateur. L'architecture de celui-ci est construite autour d'une unite centrale, la "Principale", dont les liens et les ramifications avec les autres unites confere a l'ensemble du simulateur sa souplesse et sa facilite d'utilisation. Le simulateur "Genetique", a l'etat de prototype, et la documentation qui lui est afferente ont ete soumis a deux mises a l'essai: l'une fonctionnelle, l'autre empirique. La mise a l'essai fonctionnelle, menee aupres d'un groupe d'enseignants experts, a permis d'identifier les lacunes du materiel elabore afin de lui apporter les reajustements qui s'imposaient. La mise a l'essai empirique, conduite par un groupe de onze (11) etudiants de niveau secondaire, avait pour but, d'une part, de tester la facilite d'utilisation du simulateur "Genetique" ainsi que les documents d'accompagnement et, d'autre part, de verifier si les participants retiraient des avantages pedagogiques de cet environnement. Trois techniques furent exploitees pour recolter les donnees de la mise a l'essai empirique. L'analyse des resultats a permis de faire un retour critique sur les productions concretes de cette recherche et d'apporter les modifications necessaires tant au simulateur qu'aux documents d'accompagnement. Cette analyse a permis egalement de conclure que notre simulateur interactif favorise une approche inductive permettant aux etudiants de s'approprier les lois probabilistes de Mendel. Enfin, la conclusion degage des pistes de recherches destinees aux etudes ulterieures, plus particulierement celles qui s'interessent a developper des simulateurs, afin d'integrer a ceux-ci des representations concretes et abstraites presentees en temps reel. Les disquettes du simulateur "Genetique" et les documents d'accompagnement sont annexes a la presente recherche.

The multi-queue model applied to random access protocol

NASA Astrophysics Data System (ADS)

Fan, Xinlong

2013-03-01

The connection of everything in a sensory and an intelligent way is a pursuit in smart environment. This paper introduces the engineered cell-sensors into the multi-agent systems to realize the smart environment. The seamless interface with the natural environment and strong information-processing ability of cell with the achievements of synthetic biology make the construction of engineered cell-sensors possible. However, the engineered cell-sensors are only simple-functional and unreliable computational entities. Therefore how to combine engineered cell-sensors with digital device is a key problem in order to realize the smart environment. We give the abstract structure and interaction modes of the engineered cell-sensors in order to introduce engineered cell-sensors into multi-agent systems. We believe that the introduction of engineered cell-sensors will push forward the development of the smart environment.

40 CFR 300.140 - Multi-regional responses.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 28 2011-07-01 2011-07-01 false Multi-regional responses. 300.140 Section 300.140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY... hazardous waste management facilities located in the coastal zone, responsibility for response action shall...

40 CFR 300.140 - Multi-regional responses.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 29 2013-07-01 2013-07-01 false Multi-regional responses. 300.140 Section 300.140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY... hazardous waste management facilities located in the coastal zone, responsibility for response action shall...

40 CFR 300.140 - Multi-regional responses.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 27 2010-07-01 2010-07-01 false Multi-regional responses. 300.140 Section 300.140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY... hazardous waste management facilities located in the coastal zone, responsibility for response action shall...

40 CFR 300.140 - Multi-regional responses.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 29 2012-07-01 2012-07-01 false Multi-regional responses. 300.140 Section 300.140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY... hazardous waste management facilities located in the coastal zone, responsibility for response action shall...

40 CFR 300.140 - Multi-regional responses.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 28 2014-07-01 2014-07-01 false Multi-regional responses. 300.140 Section 300.140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY... hazardous waste management facilities located in the coastal zone, responsibility for response action shall...

Genomic-Enabled Prediction Kernel Models with Random Intercepts for Multi-environment Trials.

PubMed

Cuevas, Jaime; Granato, Italo; Fritsche-Neto, Roberto; Montesinos-Lopez, Osval A; Burgueño, Juan; Bandeira E Sousa, Massaine; Crossa, José

2018-03-28

In this study, we compared the prediction accuracy of the main genotypic effect model (MM) without G×E interactions, the multi-environment single variance G×E deviation model (MDs), and the multi-environment environment-specific variance G×E deviation model (MDe) where the random genetic effects of the lines are modeled with the markers (or pedigree). With the objective of further modeling the genetic residual of the lines, we incorporated the random intercepts of the lines ([Formula: see text]) and generated another three models. Each of these 6 models were fitted with a linear kernel method (Genomic Best Linear Unbiased Predictor, GB) and a Gaussian Kernel (GK) method. We compared these 12 model-method combinations with another two multi-environment G×E interactions models with unstructured variance-covariances (MUC) using GB and GK kernels (4 model-method). Thus, we compared the genomic-enabled prediction accuracy of a total of 16 model-method combinations on two maize data sets with positive phenotypic correlations among environments, and on two wheat data sets with complex G×E that includes some negative and close to zero phenotypic correlations among environments. The two models (MDs and MDE with the random intercept of the lines and the GK method) were computationally efficient and gave high prediction accuracy in the two maize data sets. Regarding the more complex G×E wheat data sets, the prediction accuracy of the model-method combination with G×E, MDs and MDe, including the random intercepts of the lines with GK method had important savings in computing time as compared with the G×E interaction multi-environment models with unstructured variance-covariances but with lower genomic prediction accuracy. Copyright © 2018 Cuevas et al.

Genomic-Enabled Prediction Kernel Models with Random Intercepts for Multi-environment Trials

PubMed Central

Cuevas, Jaime; Granato, Italo; Fritsche-Neto, Roberto; Montesinos-Lopez, Osval A.; Burgueño, Juan; Bandeira e Sousa, Massaine; Crossa, José

2018-01-01

In this study, we compared the prediction accuracy of the main genotypic effect model (MM) without G×E interactions, the multi-environment single variance G×E deviation model (MDs), and the multi-environment environment-specific variance G×E deviation model (MDe) where the random genetic effects of the lines are modeled with the markers (or pedigree). With the objective of further modeling the genetic residual of the lines, we incorporated the random intercepts of the lines (l) and generated another three models. Each of these 6 models were fitted with a linear kernel method (Genomic Best Linear Unbiased Predictor, GB) and a Gaussian Kernel (GK) method. We compared these 12 model-method combinations with another two multi-environment G×E interactions models with unstructured variance-covariances (MUC) using GB and GK kernels (4 model-method). Thus, we compared the genomic-enabled prediction accuracy of a total of 16 model-method combinations on two maize data sets with positive phenotypic correlations among environments, and on two wheat data sets with complex G×E that includes some negative and close to zero phenotypic correlations among environments. The two models (MDs and MDE with the random intercept of the lines and the GK method) were computationally efficient and gave high prediction accuracy in the two maize data sets. Regarding the more complex G×E wheat data sets, the prediction accuracy of the model-method combination with G×E, MDs and MDe, including the random intercepts of the lines with GK method had important savings in computing time as compared with the G×E interaction multi-environment models with unstructured variance-covariances but with lower genomic prediction accuracy. PMID:29476023

A New Time-varying Concept of Risk in a Changing Climate.

PubMed

Sarhadi, Ali; Ausín, María Concepción; Wiper, Michael P

2016-10-20

In a changing climate arising from anthropogenic global warming, the nature of extreme climatic events is changing over time. Existing analytical stationary-based risk methods, however, assume multi-dimensional extreme climate phenomena will not significantly vary over time. To strengthen the reliability of infrastructure designs and the management of water systems in the changing environment, multidimensional stationary risk studies should be replaced with a new adaptive perspective. The results of a comparison indicate that current multi-dimensional stationary risk frameworks are no longer applicable to projecting the changing behaviour of multi-dimensional extreme climate processes. Using static stationary-based multivariate risk methods may lead to undesirable consequences in designing water system infrastructures. The static stationary concept should be replaced with a flexible multi-dimensional time-varying risk framework. The present study introduces a new multi-dimensional time-varying risk concept to be incorporated in updating infrastructure design strategies under changing environments arising from human-induced climate change. The proposed generalized time-varying risk concept can be applied for all stochastic multi-dimensional systems that are under the influence of changing environments.

Risk Assessment References: Documented Literature Search

DTIC Science & Technology

2012-10-01

the Minister of National Defence, 2012 © Sa Majesté la Reine (en droit du Canada), telle que représentée par le ministre de la Défense nationale...vise à démontrer la valeur de l’approche scientifique pour améliorer les capacités de gestion des situations d’urgence en se concentrant sur...l’évaluation des risques et les infrastructures essentielles. Au cours de la première phase du projet, RDDC a effectué une analyse documentaire

The Meta-Organization: A Research and Conceptual Landscape

DTIC Science & Technology

2011-06-01

la Reine (en droit du Canada), telle que représentée par le ministre de la Défense nationale...une approche globale en nous intéressant plus particulièrement aux problèmes pernicieux, à la convergence et à l’association, et à la gestion des ...rédigé dans le cadre du projet de modélisation de la collaboration et de la prise de décisions méta-organisationnelles financé par le

Prediction of Aerodynamic Characteristics of Fighter Wings at High Angles of Attack.

DTIC Science & Technology

1984-03-01

potential distribution throughout the network of four points on a body surface great- ly facilitates the flow analysis procedure. Tangential velocity...expensive of computer time. For example, as quoted by McLean, using this coarsest grid network , each 0 surface of the 727-200 wing required 10 minutes of...1980. 19. Le Balleur, J.C. and Neron , M., "Calcul D’Ecoulements3 Visqueux Decolles sur Profils D’Ailes par une Approche de Couplage", AGARn CP-291

Decision Rules for Pictorial Threat Classification

DTIC Science & Technology

2009-07-01

utilise un seul indice pour classifier des cibles, et la stratégie de classification bayesienne qui repose sur des modèles de statistiques...L’approche heuristique consistant à « ne garder que le meilleur en vue de la classification » (TTB-C) repose sur l’hypothèse qu’un seul repère, hautement...stratégie bayesienne repose sur le recrutement de mécanismes perceptuels automatiques, elle peut s’avérer plus profitable dans des situations où

SoC: Une Nouvelle Approche de l’Amelioration des Performances des Systemes pour Combattre les Problemes de Disponibilite a Long Terme (SoC: A New Approach to Enhance System Performances and to Combat the Long-Term Availability Issue)

DTIC Science & Technology

2001-01-01

cin~tique Properties»> ou o IP »>. En fait, ces IP ne sont rien (exemple : un missile en vol libre ). Meme si on peut d’autres que des composants sur...probablement pas radicalement le problkme peuvent soit achet~s soit &tre issus de conceptions au niveau des composants 6lectroniques. pr&c~dentes. Les

Building Effective Collaboration in a Comprehensive Approach (Etablissement d’une collaboration efficace selon une approche globale)

DTIC Science & Technology

2017-11-01

Improvement on this Construct Table Table 3-1 Inter-Agency Maturity Levels 3-3 Table 5-1 High -Low Scores for the Inter-Team Cooperation...Factors 5-4 Table 5-2 High -Low Scores for the Individual Interaction Format Items 5-4 Table 5-3 Number of Military and Civilian Respondents by Civil...a wilful dismissal of the capabilities of other entities, which can lead to an escalation of tensions within the CA collective. As a consequence, it

Experimental Investigations on the Distortion of ISAR Images Using Different Radar Waveforms

DTIC Science & Technology

2003-09-01

des cibles fera partie int~grante d’une nouvelle approche pour la gestion des donn~es relatives A l’espace de combat, comme les nouvelles initiatives de ... risque de tir fratricide en conditions de combat. En somme, l’identification des cibles, particuli~rement en mode de non-cooperation, jouera un r~le...Defence, 2003 © Sa majest6 la reine, repr~sent~e par le ministre de la Defense nationale, 2003 Abstract Experimental results have shown that the

Abundances in the Young Globulars Ruprecht 106 and PAL 12

NASA Astrophysics Data System (ADS)

Brown, J. A.; Wallerstein, G.; Zucker, D.

1995-12-01

We have observed two red giants in each of the young globular clusters Ruprecht 106 and Pal 12 with the CTIO 4m echelle and analyzed the spectra for chemical composition. We find for Rup 106 [Fe/H] =~ -1.5, [O/Fe] =~ 0.0, and [alpha /Fe] =~ -0.2. For Pal 12 we find [Fe/H] =~ -1.0 and [alpha /Fe] =~ -0.05; we have no information on oxygen in Pal 12. The light odd-Z metals Na and Al are both overdeficient in both clusters' stars. The stars are all CN-weak compared to similar giants in nearby globulars of comparable [Fe/H]. The abundance results for Rup 106 rule out the possibility that the apparent youth of the cluster as derived from its color-magnitude diagram is caused by an anomalous composition; the lack of results for oxygen prevent us from making a similar statement for Pal 12. These abundances imply a very different star formation history for the material from which these clusters formed, compared to the well-studied old nearby globulars, and are consistent with the suggestion that these clusters are accreted objects, and were not formed in the same environment as the old clusters.

Redefining the "Normal" Worker: Law and Policy Choices for Work-Family Balance in Canada: Redéfinir le 'travailleur normal': Regard sur les choix législatifs et de politiques publiques en matière de conciliation travail-famille au Canada.

PubMed

Bernstein, Stéphanie; Valentini, Mathilde

2017-11-01

While the need to reconcile work and family life has been recognized in discrete ways in legislation and policy over the years, there has not been a substantial shift away from the archetype of the "unencumbered" (male) worker to a new model of the "normal" worker. In Canada and elsewhere, legislative protection does not allow women or men to effectively reconcile work and family responsibilities over the life cycle. This paper examines the different ways in which work-family balance is regulated, with a focus on the Canadian federal jurisdiction and the province of Quebec, and underlines the need for coherent labor and social policy. The paper also explores the development of multi-stakeholder initiatives on work-family balance, including the development of voluntary standards and a proposal for a work-family "framework" law to ensure coherence among different laws and programs affecting work-family balance. The paper concludes by confirming the need to move away from an individualized approach toward a more mainstreamed and collectivized approach to work-family balance. Résumé Bien que la nécessité de concilier travail et vie familiale ait fait l'objet d'une reconnaissance timide dans la législation et les politiques publiques au fil des ans, il n'y a pas eu de changement substantiel de l'archétype du travailleur « sans engagements » (homme) vers un nouveau modèle de « travailleur normal ». Au Canada et ailleurs, la protection législative ne permet pas aux femmes ou aux hommes d'arrimer efficacement leurs responsabilités professionnelles et familiales au cours de leur vie. Cet article examine les différentes façons dont la conciliation travail-famille est réglementée, particulièrement en droit fédéral canadien et dans la province de Québec, et souligne la nécessité d'une politique sociale et de travail cohérente. Le texte explore également le développement d'initiatives multipartites, y compris l'élaboration de normes volontaires de style ISO et une proposition de loi-cadre travail-famille afin d'assurer une cohérence entre les différents lois et programmes touchant la conciliation famille-travail au Québec. L'article conclut en confirmant la nécessité de passer d'une approche individualisée à une approche plus intégrée et collectivisée de la conciliation travail-famille.

Bayesian Genomic Prediction with Genotype × Environment Interaction Kernel Models

PubMed Central

Cuevas, Jaime; Crossa, José; Montesinos-López, Osval A.; Burgueño, Juan; Pérez-Rodríguez, Paulino; de los Campos, Gustavo

2016-01-01

The phenomenon of genotype × environment (G × E) interaction in plant breeding decreases selection accuracy, thereby negatively affecting genetic gains. Several genomic prediction models incorporating G × E have been recently developed and used in genomic selection of plant breeding programs. Genomic prediction models for assessing multi-environment G × E interaction are extensions of a single-environment model, and have advantages and limitations. In this study, we propose two multi-environment Bayesian genomic models: the first model considers genetic effects (u) that can be assessed by the Kronecker product of variance–covariance matrices of genetic correlations between environments and genomic kernels through markers under two linear kernel methods, linear (genomic best linear unbiased predictors, GBLUP) and Gaussian (Gaussian kernel, GK). The other model has the same genetic component as the first model (u) plus an extra component, f, that captures random effects between environments that were not captured by the random effects u. We used five CIMMYT data sets (one maize and four wheat) that were previously used in different studies. Results show that models with G × E always have superior prediction ability than single-environment models, and the higher prediction ability of multi-environment models with u and f over the multi-environment model with only u occurred 85% of the time with GBLUP and 45% of the time with GK across the five data sets. The latter result indicated that including the random effect f is still beneficial for increasing prediction ability after adjusting by the random effect u. PMID:27793970

Bayesian Genomic Prediction with Genotype × Environment Interaction Kernel Models.

PubMed

Cuevas, Jaime; Crossa, José; Montesinos-López, Osval A; Burgueño, Juan; Pérez-Rodríguez, Paulino; de Los Campos, Gustavo

2017-01-05

The phenomenon of genotype × environment (G × E) interaction in plant breeding decreases selection accuracy, thereby negatively affecting genetic gains. Several genomic prediction models incorporating G × E have been recently developed and used in genomic selection of plant breeding programs. Genomic prediction models for assessing multi-environment G × E interaction are extensions of a single-environment model, and have advantages and limitations. In this study, we propose two multi-environment Bayesian genomic models: the first model considers genetic effects [Formula: see text] that can be assessed by the Kronecker product of variance-covariance matrices of genetic correlations between environments and genomic kernels through markers under two linear kernel methods, linear (genomic best linear unbiased predictors, GBLUP) and Gaussian (Gaussian kernel, GK). The other model has the same genetic component as the first model [Formula: see text] plus an extra component, F: , that captures random effects between environments that were not captured by the random effects [Formula: see text] We used five CIMMYT data sets (one maize and four wheat) that were previously used in different studies. Results show that models with G × E always have superior prediction ability than single-environment models, and the higher prediction ability of multi-environment models with [Formula: see text] over the multi-environment model with only u occurred 85% of the time with GBLUP and 45% of the time with GK across the five data sets. The latter result indicated that including the random effect f is still beneficial for increasing prediction ability after adjusting by the random effect [Formula: see text]. Copyright © 2017 Cuevas et al.

The Moderating Effect of Health-Improving Workplace Environment on Promoting Physical Activity in White-Collar Employees: A Multi-Site Longitudinal Study Using Multi-Level Structural Equation Modeling.

PubMed

Watanabe, Kazuhiro; Otsuka, Yasumasa; Shimazu, Akihito; Kawakami, Norito

2016-02-01

This longitudinal study aimed to investigate the moderating effect of health-improving workplace environment on relationships between physical activity, self-efficacy, and psychological distress. Data were collected from 16 worksites and 129 employees at two time-points. Health-improving workplace environment was measured using the Japanese version of the Environmental Assessment Tool. Physical activity, self-efficacy, and psychological distress were also measured. Multi-level structural equation modeling was used to investigate the moderating effect of health-improving workplace environment on relationships between psychological distress, self-efficacy, and physical activity. Psychological distress was negatively associated with physical activity via low self-efficacy. Physical activity was negatively related to psychological distress. Physical activity/fitness facilities in the work environment exaggerated the positive relationship between self-efficacy and physical activity. Physical activity/fitness facilities in the workplace may promote employees' physical activity.

Electronic Structure Calculations and Adaptation Scheme in Multi-core Computing Environments

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

Seshagiri, Lakshminarasimhan; Sosonkina, Masha; Zhang, Zhao

2009-05-20

Multi-core processing environments have become the norm in the generic computing environment and are being considered for adding an extra dimension to the execution of any application. The T2 Niagara processor is a very unique environment where it consists of eight cores having a capability of running eight threads simultaneously in each of the cores. Applications like General Atomic and Molecular Electronic Structure (GAMESS), used for ab-initio molecular quantum chemistry calculations, can be good indicators of the performance of such machines and would be a guideline for both hardware designers and application programmers. In this paper we try to benchmarkmore » the GAMESS performance on a T2 Niagara processor for a couple of molecules. We also show the suitability of using a middleware based adaptation algorithm on GAMESS on such a multi-core environment.« less

Analysis of yield and oil from a series of canola breeding trials. Part II. Exploring variety by environment interaction using factor analysis.

PubMed

Cullis, B R; Smith, A B; Beeck, C P; Cowling, W A

2010-11-01

Exploring and exploiting variety by environment (V × E) interaction is one of the major challenges facing plant breeders. In paper I of this series, we presented an approach to modelling V × E interaction in the analysis of complex multi-environment trials using factor analytic models. In this paper, we develop a range of statistical tools which explore V × E interaction in this context. These tools include graphical displays such as heat-maps of genetic correlation matrices as well as so-called E-scaled uniplots that are a more informative alternative to the classical biplot for large plant breeding multi-environment trials. We also present a new approach to prediction for multi-environment trials that include pedigree information. This approach allows meaningful selection indices to be formed either for potential new varieties or potential parents.

Coupled multi-disciplinary simulation of composite engine structures in propulsion environment

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Singhal, Surendra N.

1992-01-01

A computational simulation procedure is described for the coupled response of multi-layered multi-material composite engine structural components which are subjected to simultaneous multi-disciplinary thermal, structural, vibration, and acoustic loadings including the effect of hostile environments. The simulation is based on a three dimensional finite element analysis technique in conjunction with structural mechanics codes and with acoustic analysis methods. The composite material behavior is assessed at the various composite scales, i.e., the laminate/ply/constituents (fiber/matrix), via a nonlinear material characterization model. Sample cases exhibiting nonlinear geometrical, material, loading, and environmental behavior of aircraft engine fan blades, are presented. Results for deformed shape, vibration frequency, mode shapes, and acoustic noise emitted from the fan blade, are discussed for their coupled effect in hot and humid environments. Results such as acoustic noise for coupled composite-mechanics/heat transfer/structural/vibration/acoustic analyses demonstrate the effectiveness of coupled multi-disciplinary computational simulation and the various advantages of composite materials compared to metals.

VizieR Online Data Catalog: Star cluster Gaia 1 stars equivalent widths (Koch+, 2018)

NASA Astrophysics Data System (ADS)

Koch, A.; Hansen, T.; Kunder, A.

2017-09-01

Observations of four candidate members were taken during four nights in March 2017 using the Echelle spectrograph at the 2.5-m du Pont telescope at the Las Campanas Observatory, Chile, with a seeing of 0.7"-1.0" throughout the nights. Our spectroscopic set-up included a 1.0" slit with 2x1 binning in spectral and spatial dimensions, resulting in a resolving power of R~25000. (2 data files).

The New Instrument Suite of the TSU/Fairborn 2m Automatic Spectroscopic Telescope

NASA Astrophysics Data System (ADS)

Muterspaugh, Matthew W.; Maxwell, T.; Williamson, M. W.; Fekel, F. C.; Ge, J.; Kelly, J.; Ghasempour, A.; Powell, S.; Zhao, B.; Varosi, F.; Schofield, S.; Liu, J.; Warner, C.; Jakeman, H.; Avner, L.; Swihart, S.; Harrison, C.; Fishler, D.

2014-01-01

Tied with the Liverpool Telescope as the world's largest fully robotic optical research telescope, Tennessee State University's (TSU) 2m Automatic Spectroscopic Telescope (AST) has recently been upgraded to improve performance and increase versatility by supporting multiple instruments. Its second-generation instrument head enables us to rapidly switch between any of up to twelve fibers optics, each of which can supply light to a different instrument. In 2013 construction was completed on a new temperature-controlled guest instrument building, and two new high resolution spectrographs were commissioned. The current set of instrumentation includes (1) the telescope's original R=30,000 echelle spectrograph (0.38--0.83 microns simultaneous), (2) a single order R=7,000 spectrograph centered at Ca H&K features, (3) a single-mode-fiber fed miniature echelle spectrograph (R=100,000; 0.48--0.62 microns simultaneous), (4) the University of Florida's EXPERT-3 spectrograph (R=100,000; 0.38--0.9 microns simultaneous; vacuum and temperature controlled) and (5) the University of Florida's FIRST spectrograph (R=70,000$; 0.8--1.35 or 1.4--1.8 microns simultaneous; vacuum and temperature controlled). Future instruments include the Externally Dispersed Interferometry (EDI) Testbed, a combination low resolution dispersed spectrograph and Fourier Transform Spectrograph. We welcome inquiries from the community in regards to observing access and/or proposals for future guest instruments.

The NASA Exoplanet Science Institute Archives: KOA and NStED

NASA Astrophysics Data System (ADS)

Berriman, G. B.; Ciardi, D.; Abajian, M.; Barlow, T.; Bryden, G.; von Braun, K.; Good, J.; Kane, S.; Kong, M.; Laity, A.; Lynn, M.; Elroy, D. M.; Plavchan, P.; Ramirez, S.; Schmitz, M.; Stauffer, J.; Wyatt, P.; Zhang, A.; Goodrich, R.; Mader, J.; Tran, H.; Tsubota, M.; Beekley, A.; Berukoff, S.; Chan, B.; Lau, C.; Regelson, M.; Saucedo, M.; Swain, M.

2010-12-01

The NASA Exoplanet Science Institute (NExScI) maintains a series of archival services in support of NASA’s planet finding and characterization goals. Two of the larger archival services at NExScI are the Keck Observatory Archive (KOA) and the NASA Star and Exoplanet Database (NStED). KOA, a collaboration between the W. M. Keck Observatory and NExScI, serves raw data from the High Resolution Echelle Spectrograph (HIRES) and extracted spectral browse products. As of June 2009, KOA hosts over 28 million files (4.7 TB) from over 2,000 nights. In Spring 2010, it will begin to serve data from the Near-Infrared Echelle Spectrograph (NIRSPEC). NStED is a general purpose archive with the aim of providing support for NASA’s planet finding and characterization goals, and stellar astrophysics. There are two principal components of NStED: a database of (currently) all known exoplanets, and images; and an archive dedicated to high precision photometric surveys for transiting exoplanets. NStED is the US portal to the CNES mission CoRoT, the first space mission dedicated to the discovery and characterization of exoplanets. These archives share a common software and hardware architecture with the NASA/IPAC Infrared Science Archive (IRSA). The software architecture consists of standalone utilities that perform generic query and retrieval functions. They are called through program interfaces and plugged together to form applications through a simple executive library.

NRES: The Network of Robotic Echelle Spectrographs

NASA Astrophysics Data System (ADS)

Siverd, Robert; Brown, Timothy M.; Henderson, Todd; Hygelund, John; Barnes, Stuart; Bowman, Mark; De Vera, Jon; Eastman, Jason D.; Kirby, Annie; Norbury, Martin; Smith, Cary; Taylor, Brook; Tufts, Joseph; Van Eyken, Julian C.

2017-06-01

Las Cumbres Observatory (LCO) is building the Network of Robotic Echelle Spectrographs (NRES), which will consist of four to six identical, optical (390 - 860 nm) high-precision spectrographs, each fiber-fed simultaneously by up to two 1-meter telescopes and a Thorium-Argon calibration source. We plan to install one at up to 6 observatory sites in the Northern and Southern hemispheres, creating a single, globally-distributed, autonomous spectrograph facility using up to ten 1-m telescopes. Simulations suggest we will achieve long-term radial velocity precision of 3 m/s in less than an hour for stars brighter than V = 11 or 12. Following a few months of on-sky evaluation at our BPL test facility, the first spectrograph unit was shipped to CTIO in late 2016 and installed in March 2017. Barring serious complications, we expect regular scheduled science observing to begin in mid-2017. Three additional units are in building or testing phases and slated for deployment in late 2017. Acting in concert, these four spectrographs will provide a new, unique facility for stellar characterization and precise radial velocities. We will briefly overview the LCO telescope network, the NRES spectrograph design, the advantages it provides, and development challenges we encountered along the way. We will further discuss real-world performance from our first unit, initial science results, and the ongoing software development effort needed to automate such a facility for a wide array of science cases.

StarCAT: A Catalog of Space Telescope Imaging Spectrograph Ultraviolet Echelle Spectra of Stars

NASA Astrophysics Data System (ADS)

Ayres, Thomas R.

2010-03-01

StarCAT is a catalog of high resolution ultraviolet spectra of objects classified as "stars," recorded by Space Telescope Imaging Spectrograph (STIS) during its initial seven years of operations (1997-2004). StarCAT is based on 3184 echelle observations of 545 distinct targets, with a total exposure duration of 5.2 Ms. For many of the objects, broad ultraviolet coverage has been achieved by splicing echellegrams taken in two or more FUV (1150-1700 Å) and/or NUV (1600-3100 Å) settings. In cases of multiple pointings on conspicuously variable sources, spectra were separated into independent epochs. Otherwise, different epochs were combined to enhance the signal-to-noise ratio (S/N). A post-facto correction to the calstis pipeline data sets compensated for subtle wavelength distortions identified in a previous study of the STIS calibration lamps. An internal "fluxing" procedure yielded coherent spectral energy distributions (SEDs) for objects with broadly overlapping wavelength coverage. The best StarCAT material achieves 300 m s-1 internal velocity precision; absolute accuracy at the 1 km s-1 level; photometric accuracy of order 4%; and relative flux precision several times better (limited mainly by knowledge of SEDs of UV standard stars). While StarCAT represents a milestone in the large-scale post-processing of STIS echellegrams, a number of potential improvements in the underlying "final" pipeline are identified.

Accuracies of univariate and multivariate genomic prediction models in African cassava.

PubMed

Okeke, Uche Godfrey; Akdemir, Deniz; Rabbi, Ismail; Kulakow, Peter; Jannink, Jean-Luc

2017-12-04

Genomic selection (GS) promises to accelerate genetic gain in plant breeding programs especially for crop species such as cassava that have long breeding cycles. Practically, to implement GS in cassava breeding, it is necessary to evaluate different GS models and to develop suitable models for an optimized breeding pipeline. In this paper, we compared (1) prediction accuracies from a single-trait (uT) and a multi-trait (MT) mixed model for a single-environment genetic evaluation (Scenario 1), and (2) accuracies from a compound symmetric multi-environment model (uE) parameterized as a univariate multi-kernel model to a multivariate (ME) multi-environment mixed model that accounts for genotype-by-environment interaction for multi-environment genetic evaluation (Scenario 2). For these analyses, we used 16 years of public cassava breeding data for six target cassava traits and a fivefold cross-validation scheme with 10-repeat cycles to assess model prediction accuracies. In Scenario 1, the MT models had higher prediction accuracies than the uT models for all traits and locations analyzed, which amounted to on average a 40% improved prediction accuracy. For Scenario 2, we observed that the ME model had on average (across all locations and traits) a 12% improved prediction accuracy compared to the uE model. We recommend the use of multivariate mixed models (MT and ME) for cassava genetic evaluation. These models may be useful for other plant species.

The Control Based on Internal Average Kinetic Energy in Complex Environment for Multi-robot System

NASA Astrophysics Data System (ADS)

Yang, Mao; Tian, Yantao; Yin, Xianghua

In this paper, reference trajectory is designed according to minimum energy consumed for multi-robot system, which nonlinear programming and cubic spline interpolation are adopted. The control strategy is composed of two levels, which lower-level is simple PD control and the upper-level is based on the internal average kinetic energy for multi-robot system in the complex environment with velocity damping. Simulation tests verify the effectiveness of this control strategy.

Global Village as Virtual Community (On Writing, Thinking, and Teacher Education).

ERIC Educational Resources Information Center

Polin, Linda

1993-01-01

Describes virtual communities known as Multi-User Simulated Environment (MUSE) or Multi-User Object Oriented environment (MOO), text-based computer "communities" whose inhabitants are a combination of the real people and constructed objects that people agree to treat as real. Describes their uses in the classroom. (SR)

PMHT Approach for Multi-Target Multi-Sensor Sonar Tracking in Clutter.

PubMed

Li, Xiaohua; Li, Yaan; Yu, Jing; Chen, Xiao; Dai, Miao

2015-11-06

Multi-sensor sonar tracking has many advantages, such as the potential to reduce the overall measurement uncertainty and the possibility to hide the receiver. However, the use of multi-target multi-sensor sonar tracking is challenging because of the complexity of the underwater environment, especially the low target detection probability and extremely large number of false alarms caused by reverberation. In this work, to solve the problem of multi-target multi-sensor sonar tracking in the presence of clutter, a novel probabilistic multi-hypothesis tracker (PMHT) approach based on the extended Kalman filter (EKF) and unscented Kalman filter (UKF) is proposed. The PMHT can efficiently handle the unknown measurements-to-targets and measurements-to-transmitters data association ambiguity. The EKF and UKF are used to deal with the high degree of nonlinearity in the measurement model. The simulation results show that the proposed algorithm can improve the target tracking performance in a cluttered environment greatly, and its computational load is low.

Application du concept de maillon faible à un critère d'endurance multiaxial

NASA Astrophysics Data System (ADS)

Flacelière, L.; Morel, F.; Palin-Luc, T.

2002-12-01

En fatigue à grand nombre de cycle, il est aujourd'hui admis que la distribution des contraintes, ainsi que la taille des composants, sont responsables de variations de la limite de fatigue. Sous chargement uniaxial ou multiaxial, on peut montrer qu'une approche statistique dite du maillon le plus faible, combiné à un critère multiaxial d'endurance basé sur une analyse micro plastique, permet de prédire la limite de fatigue de plusieurs matériaux métalliques. Quatre types de chargement sont analysés (traction-compression, torsion, flexion rotative et flexion plane), puis comparées aux résultats expérimentaux, pour une fonte et deux aciers haute résistance. L'approche statistique proposée permet d'intégrer un certain nombre d'aspects: la dispersion des données pour tous types de chargement, l'effet de gradient et l'influence de la présence de défauts matériaux. Enfin, ce modèle rend également compte de la diminution de la limite de fatigue avec l'augmentation du volume contraint. Les prédictions des probabilités de rupture sont raisonnables bien que seules des limites de fatigue relatives à des probabilités de rupture de 50% soient utilisées pour l'identification des paramètres du modèle.

Prédiction du comportement à long terme des matériaux polymères

NASA Astrophysics Data System (ADS)

Lemaire, J.

1998-06-01

Most of the world activity on research, development and control of polymer durability is still based on empirical techniques developed in the early ages of polymer uses. Those techniques should be critically analysed considering the state of the art in the fundamental understanding of these complex phenomena. A more rational approach is described, especially to predict the lifetime of polymeric materials in environmental conditions. That approach is based on the recognition of the chemical evolution mechanisms. Les activités de recherche, développement et contrôle de durabilité des matériaux polymères sont encore, pour une part très importante, basées sur l'emploi de techniques empiriques dont les principes ont été énoncés dès le début de l'exploitation de ces matériaux. Une analyse critique de ces méthodes s'impose aujourd'hui en tenant compte de l'avancement des connaissances. Une approche plus rationnelle est décrite, approche basée sur la reconnaissance des mécanismes d'évolution chimique. A titre d'exemple, le mécanisme d'évolution du PVC sous contraintes conjuguées de l'UV, de la chaleur et de l'oxygène, est décrit. Des études récentes de photooxydation de polymères conducteurs au sein de polyéthylène sont également succinctement rapportées.

A multi-band environment-adaptive approach to noise suppression for cochlear implants.

PubMed

Saki, Fatemeh; Mirzahasanloo, Taher; Kehtarnavaz, Nasser

2014-01-01

This paper presents an improved environment-adaptive noise suppression solution for the cochlear implants speech processing pipeline. This improvement is achieved by using a multi-band data-driven approach in place of a previously developed single-band data-driven approach. Seven commonly encountered noisy environments of street, car, restaurant, mall, bus, pub and train are considered to quantify the improvement. The results obtained indicate about 10% improvement in speech quality measures.

Modeling activity recognition of multi resident using label combination of multi label classification in smart home

NASA Astrophysics Data System (ADS)

Mohamed, Raihani; Perumal, Thinagaran; Sulaiman, Md Nasir; Mustapha, Norwati; Zainudin, M. N. Shah

2017-10-01

Pertaining to the human centric concern and non-obtrusive way, the ambient sensor type technology has been selected, accepted and embedded in the environment in resilient style. Human activities, everyday are gradually becoming complex and thus complicate the inferences of activities when it involving the multi resident in the same smart environment. Current works solutions focus on separate model between the resident, activities and interactions. Some study use data association and extra auxiliary of graphical nodes to model human tracking information in an environment and some produce separate framework to incorporate the auxiliary for interaction feature model. Thus, recognizing the activities and which resident perform the activity at the same time in the smart home are vital for the smart home development and future applications. This paper will cater the above issue by considering the simplification and efficient method using the multi label classification framework. This effort eliminates time consuming and simplifies a lot of pre-processing tasks comparing with previous approach. Applications to the multi resident multi label learning in smart home problems shows the LC (Label Combination) using Decision Tree (DT) as base classifier can tackle the above problems.

Modular "plug-and-play" capsules for multi-capsule environment in the gastrointestinal tract.

PubMed

Phee, S J; Ting, E K; Lin, L; Huynh, V A; Kencana, A P; Wong, K J; Tan, S L

2009-01-01

The invention of wireless capsule endoscopy has opened new ways of diagnosing and treating diseases in the gastrointestinal tract. Current wireless capsules can perform simple operations such as imaging and data collection (like temperature, pressure, and pH) in the gastrointestinal tract. Researchers are now focusing on adding more sophisticated functions such as drug delivery, surgical clips/tags deployment, and tissue samples collection. The finite on-board power on these capsules is one of the factors that limits the functionalities of these wireless capsules. Thus multiple application-specific capsules would be needed to complete an endoscopic operation. This would give rise to a multi-capsule environment. Having a modular "plug-and-play" capsule design would facilitate doctors in configuring multiple application-specific capsules, e.g. tagging capsule, for use in the gastrointestinal tract. This multi-capsule environment also has the advantage of reducing power consumption through asymmetric multi-hop communication.

Expert diagnostics system as a part of analysis software for power mission operations

NASA Technical Reports Server (NTRS)

Harris, Jennifer A.; Bahrami, Khosrow A.

1993-01-01

The operation of interplanetary spacecraft at JPL has become an increasingly complex activity. This complexity is due to advanced spacecraft designs and ambitious mission objectives which lead to operations requirements that are more demanding than those of any previous mission. For this reason, several productivity enhancement measures are underway at JPL within mission operations, particularly in the spacecraft analysis area. These measures aimed at spacecraft analysis include: the development of a multi-mission, multi-subsystem operations environment; the introduction of automated tools into this environment; and the development of an expert diagnostics system. This paper discusses an effort to integrate the above mentioned productivity enhancement measures. A prototype was developed that integrates an expert diagnostics system into a multi-mission, multi-subsystem operations environment using the Galileo Power / Pyro Subsystem as a testbed. This prototype will be discussed in addition to background information associated with it.

Aborder la syllogomanie en médecine familiale

PubMed Central

Frank, Christopher; Misiaszek, Brian

2012-01-01

Résumé Objectif Examiner comment se présente la syllogomanie et suggérer aux médecins de famille des approches et des ressources pour sa prise en charge. Source des données On a fait une recension dans PubMed de 2001 à mai 2011. Le mot-clé MeSH hoarding a été utilisé pour identifier la recherche à ce sujet et passer en revue les articles portant sur les aspects neuropsychologiques de l’accumulation pathologique, son diagnostic et son traitement. Message principal La syllogomanie ou accumulation pathologique est souvent un problème peu évident en médecine familiale. Les patients qui ont une syllogomanie se présentent souvent à cause d’un événement sentinelle comme une chute ou un incendie à leur domicile. Quoique la syllogomanie soit traditionnellement associée à un trouble obsessionnel-compulsif, le plus souvent, les patients ont une maladie systémique secondaire associée à un comportement syllogomaniaque ou ont une syllogomanie en l’absence de caractéristiques compulsives considérables. On s’attend à ce que la syllogomanie soit incluse dans la 5e édition du Manuel diagnostique et statistique des troubles mentaux. Si possible, il vaut mieux prendre en charge la syllogomanie selon une approche multidisciplinaire. Un nombre grandissant de centres offrent des programmes pour améliorer les symptômes ou réduire les dangers. Il a été démontré que la prise en charge pharmacologique a une certaine utilité pour traiter les causes secondaires. Chez les personnes plus âgées, des problèmes comme la démence, la dépression et la toxicomanie sont souvent associés à un comportement d’accumulation pathologique. Il faudrait essayer de maintenir les patients à domicile dans la mesure du possible, mais l’évaluation de la capacité devrait guider l’approche à adopter. Conclusion L’accumulation pathologique est plus fréquente que ne le pensent les médecins de famille. Si on identifie une syllogomanie, il faudrait rechercher des ressources locales pour contribuer à la prise en charge. Il faut évaluer et traiter les causes sous-jacentes lorsqu’elles sont cernées. On s’attend à ce que la syllogomanie primaire compte parmi les nouveaux diagnostics dans la 5e édition du Manuel diagnostique et statistique des troubles mentaux.

Évaluer les risques dans le cas de troubles mentaux indifférenciés

PubMed Central

Silveira, José; Rockman, Patricia; Fulford, Casey; Hunter, Jon

2016-01-01

Résumé Objectif Proposer aux médecins de soins primaires une approche novatrice pour la détermination des risques et la prise de décisions cliniques connexes dans la prise en charge de troubles mentaux indifférenciés. Sources de l’information Nous avons procédé à une recherche documentaire dans PubMed, CINAHL, PsycINFO et Google Scholar à l’aide des expressions de recherche suivantes, en anglais : diagnostic uncertainty, diagnosis, risk identification, risk assessment/methods, risk, risk factors, risk management/methods, cognitive biases and psychiatry, decision making, mental disorders/diagnosis, clinical competence, evidence-based medicine, interviews as topic, psychiatry/education, psychiatry/methods, documentation/methods, forensic psychiatry/education, forensic psychiatry/methods, mental disorders/classification, mental disorders/psychology, violence/prevention and control et violence/psychology. Message principal Les troubles mentaux constituent une grande part de la pratique en soins primaires; ils se présentent souvent de manière indifférenciée et ce, pendant de longues périodes. La difficile quête d’un diagnostic peut détourner l’attention de la détermination des risques, parce que nous présumons souvent qu’il faut un diagnostic avant d’amorcer un traitement. Cette situation peut avoir contribué par inadvertance à des événements indésirables. Il faudrait en priorité se concentrer sur les points saillants relatifs aux risques que présente le patient. Cet article propose une approche novatrice pour organiser les renseignements sur le patient afin d’aider à la détermination des risques et à la prise de décisions relativement à la prise en charge des patients souffrant de troubles mentaux indifférenciés. Conclusion Une approche structurée peut aider les médecins à gérer l’incertitude clinique fréquente dans la détermination des risques chez des patients souffrant de troubles mentaux, et à composer avec l’anxiété et les biais cognitifs courants qui influencent la prise de décisions en matière de risques. En se concentrant sur les risques, les déficiences fonctionnelles et les symptômes connexes à l’aide d’un cadre novateur, les médecins peuvent répondre aux besoins immédiats de leurs patients tout en continuant à rechercher un diagnostic précis et à établir un traitement à long terme. PMID:27965332

Improving the psychosocial work environment at multi-ethnic workplaces: a multi-component intervention strategy in the cleaning industry.

PubMed

Smith, Louise Hardman; Hviid, Kirsten; Frydendall, Karen Bo; Flyvholm, Mari-Ann

2013-10-14

Global labour migration has increased in recent years and immigrant workers are often recruited into low status and low paid jobs such as cleaning. Research in a Danish context shows that immigrants working in the cleaning industry often form social networks based on shared languages and backgrounds, and that conflict between different ethnic groups may occur. This paper evaluates the impact of a multi-component intervention on the psychosocial work environment at a multi-ethnic Danish workplace in the cleaning sector. The intervention included Danish lessons, vocational training courses, and activities to improve collaboration across different groups of cleaners. Interviews about the outcome of the intervention were conducted with the cleaners and their supervisor. The Copenhagen Psychosocial Questionnaire was used as a supplement to the interviews. The results suggest that the psychosocial work environment had improved after the intervention. According to the interviews with the cleaners, the intervention had led to improved communication, trust, and collaboration. These findings are supported by the questionnaire where social support from supervisor and colleagues, social community, trust, and teamwork seem to have improved together with meaning of work, rewards, and emotional demands. The design of the intervention may provide inspiration for future psychosocial work environment interventions at multi-ethnic work places.

Improving the Psychosocial Work Environment at Multi-Ethnic Workplaces: A Multi-Component Intervention Strategy in the Cleaning Industry

PubMed Central

Smith, Louise Hardman; Hviid, Kirsten; Frydendall, Karen Bo; Flyvholm, Mari-Ann

2013-01-01

Global labour migration has increased in recent years and immigrant workers are often recruited into low status and low paid jobs such as cleaning. Research in a Danish context shows that immigrants working in the cleaning industry often form social networks based on shared languages and backgrounds, and that conflict between different ethnic groups may occur. This paper evaluates the impact of a multi-component intervention on the psychosocial work environment at a multi-ethnic Danish workplace in the cleaning sector. The intervention included Danish lessons, vocational training courses, and activities to improve collaboration across different groups of cleaners. Interviews about the outcome of the intervention were conducted with the cleaners and their supervisor. The Copenhagen Psychosocial Questionnaire was used as a supplement to the interviews. The results suggest that the psychosocial work environment had improved after the intervention. According to the interviews with the cleaners, the intervention had led to improved communication, trust, and collaboration. These findings are supported by the questionnaire where social support from supervisor and colleagues, social community, trust, and teamwork seem to have improved together with meaning of work, rewards, and emotional demands. The design of the intervention may provide inspiration for future psychosocial work environment interventions at multi-ethnic work places. PMID:24129115

Collaboration Modality, Cognitive Load, and Science Inquiry Learning in Virtual Inquiry Environments

ERIC Educational Resources Information Center

Erlandson, Benjamin E.; Nelson, Brian C.; Savenye, Wilhelmina C.

2010-01-01

Educational multi-user virtual environments (MUVEs) have been shown to be effective platforms for situated science inquiry curricula. While researchers find MUVEs to be supportive of collaborative scientific inquiry processes, the complex mix of multi-modal messages present in MUVEs can lead to cognitive overload, with learners unable to…

Introducing ORACLE: Library Processing in a Multi-User Environment.

ERIC Educational Resources Information Center

Queensland Library Board, Brisbane (Australia).

Currently being developed by the State Library of Queensland, Australia, ORACLE (On-Line Retrieval of Acquisitions, Cataloguing, and Circulation Details for Library Enquiries) is a computerized library system designed to provide rapid processing of library materials in a multi-user environment. It is based on the Australian MARC format and fully…

Secure Cooperative Data Access in Multi-Cloud Environment

ERIC Educational Resources Information Center

Le, Meixing

2013-01-01

In this dissertation, we discuss the problem of enabling cooperative query execution in a multi-cloud environment where the data is owned and managed by multiple enterprises. Each enterprise maintains its own relational database using a private cloud. In order to implement desired business services, parties need to share selected portion of their…

Preservice Teachers Experience Reading Response Pedagogy in a Multi-User Virtual Environment

ERIC Educational Resources Information Center

Dooley, Caitlin McMunn; Calandra, Brendan; Harmon, Stephen

2014-01-01

This qualitative case study describes how 18 preservice teachers learned to nurture literary meaning-making via activities based on Louise Rosenblatt's Reader Response Theory within a multi-user virtual environment (MUVE). Participants re-created and responded to scenes from selected works of children's literature in Second Life as a way to…

The circumstellar envelopes of F- and G-type supergiants in the Large Magellanic Cloud

NASA Technical Reports Server (NTRS)

Hagen, W.; Humphreys, R. M.; Stencel, R. E.

1981-01-01

The outer atmospheres of four F- and G-type supergiants in the LMC are compared with those of their Milky Way counterparts by means of 2.5 and 5.1 A/mm high dispersion Echelle spectra. Na I D line doubling indicates extensive circumstellar envelopes, mass loss rates greater than 0.00001 solar masses/year, and outflow velocities of 10-60 km/sec. The Ca II H and K lines yield new data on extragalactic star chromospheres.

Spectroastrometric Study of Ro-vibrational CO Emission from the Herbig Ae Star HD 179218 with ISHELL on the NASA Infrared Telescope Facility

NASA Astrophysics Data System (ADS)

Brittain, Sean D.; Carr, John S.; Najita, Joan R.

2018-07-01

We present analysis of commissioning M-band data acquired with the infrared echelle spectrograph (iSHELL) on NASA’s Infrared Telescope Facility. In this paper we describe the delivered performance of the instrument for these M-band observations and the data reduction process. The feasibility of using iSHELL for spectro-astrometry is tested on the Herbig Ae/Be star HD 179218 and we show that sub-milliarcsecond fidelity is achievable..

The Atmosphere as Laboratory: Aeronomy by Astronomy

NASA Technical Reports Server (NTRS)

Slanger, T. G.; Cosby, P. C.; Huestis, D. L.

2002-01-01

Astronomical sky spectra, which are byproducts of long-slit observations with echelle spectrographs on large telescopes, provide a unique platform for studying the optical emissions of excited molecules and atoms in the terrestrial atmosphere that can greatly extend present knowledge based on laboratory spectra. This paper summarizes some of the advances that have been made in our understanding of the lower electronic states of O2 and other species from the sky spectra and from direct observations of the Venus nightglow.

The Solar Spectrum 3069A-2095A from the Echelle Spectrograph Flown in 1961-1964. An Extension of Rowland’s Preliminary Table of Solar Spectrum Wavelengths.

DTIC Science & Technology

1982-12-30

Brown S. PERFORMING ORGANIZATION NAME AND ADORESS 10. PROGRAM ELEMENT. PROJECT TASK AREA & WORK UNIT NUMBERS Naval Research Laboratory 61153N...laboratory wavelengths and lished work available to mid-1981. Predicted wavelengths intensities. Although the dispersion was not constant have been used where...solar ledger. Throughout the identification work , how- Multiplet numbers (column 4) are taken from three ever, multiplet structure was considered in

Variable interstellar absorption lines in young stellar aggregates

NASA Astrophysics Data System (ADS)

Krełowski, J.; Strobel, A.; Vješnica, S.; Melekh, D.; Bondar, A.

2018-06-01

The variability of interstellar atomic lines, sporadically reported in the astronomical literature, has been confirmed both in the case of the nearby hot star δ Ori and the very young and violent star-forming region η Carinae, using high-resolution echelle spectra. The presented variability concerns the intensities and profiles of Na I, K I and Ca II. The time-scale of the above-mentioned variations clearly suggests very local phenomena as their cause. It is important to say that not all interstellar lines vary in unison.

The Spectrum analysis of three chromospherically active binary stars.

NASA Astrophysics Data System (ADS)

Gu, Shenghong; Tan, Huisong; Liu, Yuefu

1999-12-01

The authors present the research results on new CCD spectroscopic observations of three chromospherically active binary stars (BY Dra class), which were obtained by means of Coudé echelle spectrograph fed by the 2.16 m telescope at Beijing Astronomical Observatory. With the aid of stellar model atmosphere, the autors have analyzed these spectra and derived the average metal abundance and Li abundance of three systems. Using two special spectral lines, they have alsop discussed the chromospheric activity indicators of them.

A pressure scanning Fabry-Perot magnetometer.

NASA Technical Reports Server (NTRS)

Fay, T. D.; Wyller, A. A.

1971-01-01

Description of an oscillating magnetic analyzer (KDP crystal plus Glan-Thompson prism) coupled to an echelle-interferometer spectrograph, and of single-slit magnetometer which by pressure variations can be made to scan the entire profiles of the circularly and linearly polarized Zeeman components. Freon gas is used as the scanner gas with wavelength displacements of 0.02 A per 0.1 in. Hg pressure change at the NaD lines. The available scan range is 15 A in the visual spectral region.

VizieR Online Data Catalog: The hot Jupiter Kepler-13Ab planet's occultation (Shporer+, 2014)

NASA Astrophysics Data System (ADS)

Shporer, A.; O'Rourke, J. G.; Knutson, H. A.; Szabo, G. M.; Zhao, M.; Burrows, A.; Fortney, J.; Agol, E.; Cowan, N. B.; Desert, J.-M.; Howard, A. W.; Isaacson, H.; Lewis, N. K.; Showman, A. P.; Todorov, K. O.

2017-07-01

Here we carry out an atmospheric characterization of Kepler-13Ab by measuring its occultation in four different wavelength bands, from the infrared (IR; Spitzer/Infrared array camera (IRAC) 4.5 um and 3.6 um), through the near-IR (NIR; Ks band), to the optical (Kepler). We also analyze the Kepler phase curve and obtain Keck/high-resolution echelle spectrometer (HIRES) spectra that result in revised parameters for the objects in the system. (4 data files).

VizieR Online Data Catalog: Spectroscopy of V Tri (Ren+, 2017)

NASA Astrophysics Data System (ADS)

Ren, A. B.; Zhang, X. B.; Fu, J. N.; Zhang, Y. P.; Cang, T. Q.; Fox-Machado, L.; Li, C. Q.; Khokhuntod, P.; Luo, Y. P.

2017-08-01

The spectroscopic observations for V Tri were carried out with the 2.12m telescope at the Observatorio Astronemico Nacional on the Sierra San Pedro Martir (OAN-SPM) in Mexico on 2015 November 03 and 05. We used a 2048*2048 E2V CCD-4240 to collect the high-resolution (the maximum resolution is R=18000 at 5000Å) echelle spectra at the slit size 1''. The spectral range coverage was from 3800 to 7100Å (4 data files).

Mode identification from spectroscopy of gravity-mode pulsators

NASA Astrophysics Data System (ADS)

Pollard, K. R.; Brunsden, E.; Cottrell, P. L.; Davie, M.; Greenwood, A.; Wright, D. J.; De Cat, P.

2014-02-01

The gravity modes present in γ Doradus stars probe the deep stellar interiors and are thus of particular interest in asteroseismology. For the MUSICIAN programme at the University of Canterbury, we obtain extensive high-resolution echelle spectra of γ Dor stars from the Mt John University Observatory in New Zealand. We analyze these to obtain the pulsational frequencies and identify these with the multiple pulsational modes excited in the star. A summary of recent results from our spectroscopic mode-identification programme is given.

Incrementando la calidad de los espectros echelle

NASA Astrophysics Data System (ADS)

Pintado, O. I.; Adelman, S. J.

For more than 10 years we have obtained spectra with the REOSC and EBASIM spectrograph at CASLEO. Usually we use IRAF to extract the spectra. Then we normalized the 1-d spectra and measured the lines with REDUCE. In this paper we compare the results obtained using each program in different parts of the spectrum measurements process. Wih EBASIM, or 4th magnitude stars and 120 minute exposures we obtain signal-to-noise ratios near 500 in the center of the orders

VizieR Online Data Catalog: Abundances for all seven stars in Latham 1 (O'Connell+, 2016)

NASA Astrophysics Data System (ADS)

O'Connell, J. E.; Martens, K.; Frinchaboy, P. M.

2017-03-01

Observations for all target stars were obtained at McDonald Observatory with the Otto Struve 2.1m telescope instrumented with the Sandiford Cass Echelle Spectrometer (SES; R=λ/Δλ~60000) in 2013 and 2014 June. The spectrograph setup was centered near 6175Å in 2013 and 6375Å in 2014 with wavelength coverage spanning from ~5350-6560Å and ~5560-6750Å, respectively (see Table2 for observation dates and exposure times). (3 data files).

bHROS: A New High-Resolution Spectrograph Available on Gemini South

NASA Astrophysics Data System (ADS)

Margheim, S. J.; Gemini bHROS Team

2005-12-01

The Gemini bench-mounted High-Resolution Spectrograph (bHROS) is available for science programs beginning in 2006A. bHROS is the highest resolution (R=150,000) optical echelle spectrograph optimized for use on an 8-meter telescope. bHROS is fiber-fed via GMOS-S from the Gemini South focal plane and is available in both a dual-fiber Object/Sky mode and a single (larger) Object-only mode. Instrument characteristics and sample data taken during commissioning will be presented.

40 CFR 721.10183 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10183 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-199) is subject to reporting under this section for the...

40 CFR 721.10155 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10155 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-177) is subject to reporting under this section for the...

40 CFR 721.10183 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10183 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-199) is subject to reporting under this section for the...

40 CFR 721.10155 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10155 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-177) is subject to reporting under this section for the...

40 CFR 721.10663 - Functionalized multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... Specific Chemical Substances § 721.10663 Functionalized multi-walled carbon nanotubes (generic). (a... generically as functionalized multi-walled carbon nanotubes (PMN P-12-44) is subject to reporting under this... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Functionalized multi-walled carbon...

40 CFR 721.10663 - Functionalized multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2014 CFR

2014-07-01

... Specific Chemical Substances § 721.10663 Functionalized multi-walled carbon nanotubes (generic). (a... generically as functionalized multi-walled carbon nanotubes (PMN P-12-44) is subject to reporting under this... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Functionalized multi-walled carbon...

40 CFR 721.10183 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10183 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-199) is subject to reporting under this section for the...

40 CFR 721.10155 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10155 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-177) is subject to reporting under this section for the...

40 CFR 721.10183 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10183 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-199) is subject to reporting under this section for the...

40 CFR 721.10155 - Multi-walled carbon nanotubes (generic).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Multi-walled carbon nanotubes (generic... Specific Chemical Substances § 721.10155 Multi-walled carbon nanotubes (generic). (a) Chemical substance... multi-walled carbon nanotubes (PMN P-08-177) is subject to reporting under this section for the...

Home and Work Neighborhood Environments in Relation to Body Mass Index: The Multi-Ethnic Study of Atherosclerosis (MESA)

PubMed Central

Moore, Kari; Diez Roux, Ana V.; Auchincloss, Amy; Evenson, Kelly R.; Kaufman, Joel; Mujahid, Mahasin; Williams, Kayleen

2013-01-01

Background Little is known about neighborhood characteristics of workplaces, the extent to which they are independently and synergistically correlated with residential environments, and their impact on health. Methods This study investigated cross-sectional relationships between home and workplace neighborhood environments with body mass index (BMI) in 1,503 working participants of the Multi-Ethnic Study of Atherosclerosis (MESA) with mean age 59.6 (SD=7.4). Neighborhood features were socioeconomic status (SES), social environment (aesthetic quality, safety, and social cohesion), and physical environment (walking environment, recreational facilities, and food stores) derived from census data, locational data on businesses, and survey data. Paired t-tests and correlations compared environments overall and by distance between locations. Cross-classified multi-level models estimated associations with BMI. Results Home neighborhoods had more favorable social environments while workplaces had more favorable SES and physical environments. Workplace and home measures were correlated (0.39–0.70) and differences between home and workplaces were larger as distance increased. Associations between BMI and neighborhood SES and recreational facilities were stronger for home environment (P≤0.05) but did not significantly differ for healthy food, safety, or social cohesion. Healthy food availability at home and work appeared to act synergistically (interaction P=0.01). Conclusions Consideration of workplace environment may enhance our understanding of how place affects BMI. PMID:23868527

A Framework for Applying Point Clouds Grabbed by Multi-Beam LIDAR in Perceiving the Driving Environment

PubMed Central

Liu, Jian; Liang, Huawei; Wang, Zhiling; Chen, Xiangcheng

2015-01-01

The quick and accurate understanding of the ambient environment, which is composed of road curbs, vehicles, pedestrians, etc., is critical for developing intelligent vehicles. The road elements included in this work are road curbs and dynamic road obstacles that directly affect the drivable area. A framework for the online modeling of the driving environment using a multi-beam LIDAR, i.e., a Velodyne HDL-64E LIDAR, which describes the 3D environment in the form of a point cloud, is reported in this article. First, ground segmentation is performed via multi-feature extraction of the raw data grabbed by the Velodyne LIDAR to satisfy the requirement of online environment modeling. Curbs and dynamic road obstacles are detected and tracked in different manners. Curves are fitted for curb points, and points are clustered into bundles whose form and kinematics parameters are calculated. The Kalman filter is used to track dynamic obstacles, whereas the snake model is employed for curbs. Results indicate that the proposed framework is robust under various environments and satisfies the requirements for online processing. PMID:26404290

Toward the Development of a Canadian Less Lethal Weapon Approval Process: A Study of Contemporary Process Models

DTIC Science & Technology

2011-10-01

la Reine (en droit du Canada), telle que représentée par le ministre de la Défense nationale, 2011...validés par l’autorité d’approbation. Lorsqu’il n’existe pas de normes officielles, on utilise une approche de gestion du risque qui comprend une plus...gouvernance qui reprend les éléments clés du modèles du Royaume-Uni, l’incorporation d’un processus de gestion du risque, un énoncé des

C3I for Crisis, Emergency and Consequence Management (C3I pour la gestion des crises, des urgences et de leurs consequences)

DTIC Science & Technology

2009-05-01

Quelque soit le contexte, l’aide à la décision passe par une analyse en profondeur de trois (3) aspects importants interdépendants, à savoir le...information, including suggestions for reducing this burden to Department of Defense , Washington Headquarters Services, Directorate for Information...type de menace, nécessite en effet d’adopter une approche collective de la sécurité étendue à une coopération avec de multiples organisations civiles

Conference Proceedings on Landing Gear Design Loads (Les Charges de Dimensionnenment dans des Atterrisseurs).

DTIC Science & Technology

1991-06-01

de diff~rents parametres d’atterrissage. Ainsi !a not,,- 3 T-A-8863 ASG pr~sente les conditions initiales d’impact sous !a forme d’une cocbinaison de...comportement dynamique des sous -structures correspond antes. On peut tralter des syst~mes pouvant comporter plusleurs centaines de degr~s de libert6. Enfin, le...verticaux, l’avantage d’un tel modcle en atterrisseur sou plc est d’obtenlr une approche rationnelle des efforts lon~itudinaux du pli~nom~ne de misc en

MULTI-MEDIA MODELING : RESEARCH AND DEVELOPMENT

EPA Science Inventory

Developed by ORD in collaboration with OSW, the Multimedia, Multi-pathway, Multi-receptor Risk Assessment (3MRA) national risk assessment methodology is designed to assess risks at sites containing source(s) of contamination that may release contaminants to the environment. Or...

A collaborative interaction and visualization multi-modal environment for surgical planning.

PubMed

Foo, Jung Leng; Martinez-Escobar, Marisol; Peloquin, Catherine; Lobe, Thom; Winer, Eliot

2009-01-01

The proliferation of virtual reality visualization and interaction technologies has changed the way medical image data is analyzed and processed. This paper presents a multi-modal environment that combines a virtual reality application with a desktop application for collaborative surgical planning. Both visualization applications can function independently but can also be synced over a network connection for collaborative work. Any changes to either application is immediately synced and updated to the other. This is an efficient collaboration tool that allows multiple teams of doctors with only an internet connection to visualize and interact with the same patient data simultaneously. With this multi-modal environment framework, one team working in the VR environment and another team from a remote location working on a desktop machine can both collaborate in the examination and discussion for procedures such as diagnosis, surgical planning, teaching and tele-mentoring.

A Multi-User Virtual Environment for Building and Assessing Higher Order Inquiry Skills in Science

ERIC Educational Resources Information Center

Ketelhut, Diane Jass; Nelson, Brian C.; Clarke, Jody; Dede, Chris

2010-01-01

This study investigated novel pedagogies for helping teachers infuse inquiry into a standards-based science curriculum. Using a multi-user virtual environment (MUVE) as a pedagogical vehicle, teams of middle-school students collaboratively solved problems around disease in a virtual town called River City. The students interacted with "avatars" of…

Civic Participation among Seventh-Grade Social Studies Students in Multi-User Virtual Environments

ERIC Educational Resources Information Center

Zieger, Laura; Farber, Matthew

2012-01-01

Technological advances on the Internet now enable students to develop participation skills in virtual worlds. Similar to controlling a character in a video game, multi-user virtual environments, or MUVEs, allow participants to interact with others in synchronous, online settings. The authors of this study created a link between MUVEs and…

Exploring the Integration of Technology into Jewish Education: Multi-User Virtual Environments and Supplementary School Settings

ERIC Educational Resources Information Center

Sohn, Johannah Eve

2014-01-01

This descriptive case study explores the implementation of a multi-user virtual environment (MUVE) in a Jewish supplemental school setting. The research was conducted to present the recollections and reflections of three constituent populations of a new technology exploring constructivist education in the context of supplemental and online…

40th Annual Armament Systems: Guns-Ammunition-Rockets-Missiles Conference and Exhibition

DTIC Science & Technology

2005-04-28

Session: Medium Caliber System Oerlikon Ammunition for New Defense Environment, Mr. Allan N. Buckley, BTECH Oerlikon Contraves Pyrotec AG Multi...Environment Mr. Allan N. Buckley, BTECH Oerlikon Contraves Pyrotec AG Force Protection - Multi Mission Vehicle Armament & Air Burst Munition for...determine homogeneity – Propellant contains ~3% by weight of FS grains to adjust K

Tools and Methods for Risk Management in Multi-Site Engineering Projects

NASA Astrophysics Data System (ADS)

Zhou, Mingwei; Nemes, Laszlo; Reidsema, Carl; Ahmed, Ammar; Kayis, Berman

In today's highly global business environment, engineering and manufacturing projects often involve two or more geographically dispersed units or departments, research centers or companies. This paper attempts to identify the requirements for risk management in a multi-site engineering project environment, and presents a review of the state-of-the-art tools and methods that can be used to manage risks in multi-site engineering projects. This leads to the development of a risk management roadmap, which will underpin the design and implementation of an intelligent risk mapping system.

Chemical study of the metal-rich globular cluster NGC 5927

NASA Astrophysics Data System (ADS)

Mura-Guzmán, A.; Villanova, S.; Muñoz, C.; Tang, B.

2018-03-01

Globular clusters (GCs) are natural laboratories where stellar and chemical evolution can be studied in detail. In addition, their chemical patterns and kinematics can tell us to which Galactic structure (disc, bulge, halo or extragalactic) the cluster belongs to. NGC 5927 is one of most metal-rich GCs in the Galaxy and its kinematics links it to the thick disc. We present abundance analysis based on high-resolution spectra of seven giant stars. The data were obtained using Fibre Large Array Multi Element Spectrograph/Ultraviolet Echelle Spectrograph (UVES) spectrograph mounted on UT2 telescope of the European Southern Observatory. The principal objective of this work is to perform a wide and detailed chemical abundance analysis of the cluster and look for possible Multiple Populations (MPs). We determined stellar parameters and measured 22 elements corresponding to light (Na, Al), alpha (O, Mg, Si, Ca, Ti), iron-peak (Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn), and heavy elements (Y, Zr, Ba, Ce, Nd, Eu). We found a mean iron content of [Fe/H] = -0.47 ± 0.02 (error on the mean). We confirm the existence of MPs in this GC with an O-Na anti-correlation, and moderate spread in Al abundances. We estimate a mean [α/Fe] = 0.25 ± 0.08. Iron-peak elements show no significant spread. The [Ba/Eu] ratios indicate a predominant contribution from SNeII for the formation of the cluster.

A Search for the Transit of HD 168443b: Improved Orbital Parameters and Photometry

NASA Astrophysics Data System (ADS)

Pilyavsky, Genady; Mahadevan, Suvrath; Kane, Stephen R.; Howard, Andrew W.; Ciardi, David R.; de Pree, Chris; Dragomir, Diana; Fischer, Debra; Henry, Gregory W.; Jensen, Eric L. N.; Laughlin, Gregory; Marlowe, Hannah; Rabus, Markus; von Braun, Kaspar; Wright, Jason T.; Wang, Xuesong X.

2011-12-01

The discovery of transiting planets around bright stars holds the potential to greatly enhance our understanding of planetary atmospheres. In this work we present the search for transits of HD 168443b, a massive planet orbiting the bright star HD 168443 (V = 6.92) with a period of 58.11 days. The high eccentricity of the planetary orbit (e = 0.53) significantly enhances the a priori transit probability beyond that expected for a circular orbit, making HD 168443 a candidate for our ongoing Transit Ephemeris Refinement and Monitoring Survey. Using additional radial velocities from Keck High Resolution Echelle Spectrometer, we refined the orbital parameters of this multi-planet system and derived a new transit ephemeris for HD 168443b. The reduced uncertainties in the transit window make a photometric transit search practicable. Photometric observations acquired during predicted transit windows were obtained on three nights. Cerro Tololo Inter-American Observatory 1.0 m photometry acquired on 2010 September 7 had the required precision to detect a transit but fell just outside of our final transit window. Nightly photometry from the T8 0.8 m automated photometric telescope at Fairborn Observatory, acquired over a span of 109 nights, demonstrates that HD 168443 is constant on a timescale of weeks. Higher-cadence photometry on 2011 April 28 and June 25 shows no evidence of a transit. We are able to rule out a non-grazing transit of HD 168443b.

Computer aided design environment for the analysis and design of multi-body flexible structures

NASA Technical Reports Server (NTRS)

Ramakrishnan, Jayant V.; Singh, Ramen P.

1989-01-01

A computer aided design environment consisting of the programs NASTRAN, TREETOPS and MATLAB is presented in this paper. With links for data transfer between these programs, the integrated design of multi-body flexible structures is significantly enhanced. The CAD environment is used to model the Space Shuttle/Pinhole Occulater Facility. Then a controller is designed and evaluated in the nonlinear time history sense. Recent enhancements and ongoing research to add more capabilities are also described.

The GMT-Consortium Large Earth Finder (G-CLEF): an optical Echelle spectrograph for the Giant Magellan Telescope (GMT)

NASA Astrophysics Data System (ADS)

Szentgyorgyi, Andrew; Baldwin, Daniel; Barnes, Stuart; Bean, Jacob; Ben-Ami, Sagi; Brennan, Patricia; Budynkiewicz, Jamie; Chun, Moo-Young; Conroy, Charlie; Crane, Jeffrey D.; Epps, Harland; Evans, Ian; Evans, Janet; Foster, Jeff; Frebel, Anna; Gauron, Thomas; Guzmán, Dani; Hare, Tyson; Jang, Bi-Ho; Jang, Jeong-Gyun; Jordan, Andres; Kim, Jihun; Kim, Kang-Miin; Mendes de Oliveira, Claudia Mendes; Lopez-Morales, Mercedes; McCracken, Kenneth; McMuldroch, Stuart; Miller, Joseph; Mueller, Mark; Oh, Jae Sok; Onyuksel, Cem; Ordway, Mark; Park, Byeong-Gon; Park, Chan; Park, Sung-Joon; Paxson, Charles; Phillips, David; Plummer, David; Podgorski, William; Seifahrt, Andreas; Stark, Daniel; Steiner, Joao; Uomoto, Alan; Walsworth, Ronald; Yu, Young-Sam

2016-08-01

The GMT-Consortium Large Earth Finder (G-CLEF) will be a cross-dispersed, optical band echelle spectrograph to be delivered as the first light scientific instrument for the Giant Magellan Telescope (GMT) in 2022. G-CLEF is vacuum enclosed and fiber-fed to enable precision radial velocity (PRV) measurements, especially for the detection and characterization of low-mass exoplanets orbiting solar-type stars. The passband of G-CLEF is broad, extending from 3500Å to 9500Å. This passband provides good sensitivity at blue wavelengths for stellar abundance studies and deep red response for observations of high-redshift phenomena. The design of G-CLEF incorporates several novel technical innovations. We give an overview of the innovative features of the current design. G-CLEF will be the first PRV spectrograph to have a composite optical bench so as to exploit that material's extremely low coefficient of thermal expansion, high in-plane thermal conductivity and high stiffness-to-mass ratio. The spectrograph camera subsystem is divided into a red and a blue channel, split by a dichroic, so there are two independent refractive spectrograph cameras. The control system software is being developed in model-driven software context that has been adopted globally by the GMT. G-CLEF has been conceived and designed within a strict systems engineering framework. As a part of this process, we have developed a analytical toolset to assess the predicted performance of G-CLEF as it has evolved through design phases.

Genomic-Enabled Prediction in Maize Using Kernel Models with Genotype × Environment Interaction

PubMed Central

Bandeira e Sousa, Massaine; Cuevas, Jaime; de Oliveira Couto, Evellyn Giselly; Pérez-Rodríguez, Paulino; Jarquín, Diego; Fritsche-Neto, Roberto; Burgueño, Juan; Crossa, Jose

2017-01-01

Multi-environment trials are routinely conducted in plant breeding to select candidates for the next selection cycle. In this study, we compare the prediction accuracy of four developed genomic-enabled prediction models: (1) single-environment, main genotypic effect model (SM); (2) multi-environment, main genotypic effects model (MM); (3) multi-environment, single variance G×E deviation model (MDs); and (4) multi-environment, environment-specific variance G×E deviation model (MDe). Each of these four models were fitted using two kernel methods: a linear kernel Genomic Best Linear Unbiased Predictor, GBLUP (GB), and a nonlinear kernel Gaussian kernel (GK). The eight model-method combinations were applied to two extensive Brazilian maize data sets (HEL and USP data sets), having different numbers of maize hybrids evaluated in different environments for grain yield (GY), plant height (PH), and ear height (EH). Results show that the MDe and the MDs models fitted with the Gaussian kernel (MDe-GK, and MDs-GK) had the highest prediction accuracy. For GY in the HEL data set, the increase in prediction accuracy of SM-GK over SM-GB ranged from 9 to 32%. For the MM, MDs, and MDe models, the increase in prediction accuracy of GK over GB ranged from 9 to 49%. For GY in the USP data set, the increase in prediction accuracy of SM-GK over SM-GB ranged from 0 to 7%. For the MM, MDs, and MDe models, the increase in prediction accuracy of GK over GB ranged from 34 to 70%. For traits PH and EH, gains in prediction accuracy of models with GK compared to models with GB were smaller than those achieved in GY. Also, these gains in prediction accuracy decreased when a more difficult prediction problem was studied. PMID:28455415

Genomic-Enabled Prediction in Maize Using Kernel Models with Genotype × Environment Interaction.

PubMed

Bandeira E Sousa, Massaine; Cuevas, Jaime; de Oliveira Couto, Evellyn Giselly; Pérez-Rodríguez, Paulino; Jarquín, Diego; Fritsche-Neto, Roberto; Burgueño, Juan; Crossa, Jose

2017-06-07

Multi-environment trials are routinely conducted in plant breeding to select candidates for the next selection cycle. In this study, we compare the prediction accuracy of four developed genomic-enabled prediction models: (1) single-environment, main genotypic effect model (SM); (2) multi-environment, main genotypic effects model (MM); (3) multi-environment, single variance G×E deviation model (MDs); and (4) multi-environment, environment-specific variance G×E deviation model (MDe). Each of these four models were fitted using two kernel methods: a linear kernel Genomic Best Linear Unbiased Predictor, GBLUP (GB), and a nonlinear kernel Gaussian kernel (GK). The eight model-method combinations were applied to two extensive Brazilian maize data sets (HEL and USP data sets), having different numbers of maize hybrids evaluated in different environments for grain yield (GY), plant height (PH), and ear height (EH). Results show that the MDe and the MDs models fitted with the Gaussian kernel (MDe-GK, and MDs-GK) had the highest prediction accuracy. For GY in the HEL data set, the increase in prediction accuracy of SM-GK over SM-GB ranged from 9 to 32%. For the MM, MDs, and MDe models, the increase in prediction accuracy of GK over GB ranged from 9 to 49%. For GY in the USP data set, the increase in prediction accuracy of SM-GK over SM-GB ranged from 0 to 7%. For the MM, MDs, and MDe models, the increase in prediction accuracy of GK over GB ranged from 34 to 70%. For traits PH and EH, gains in prediction accuracy of models with GK compared to models with GB were smaller than those achieved in GY. Also, these gains in prediction accuracy decreased when a more difficult prediction problem was studied. Copyright © 2017 Bandeira e Sousa et al.

Pre-Service Teachers' Perspectives on Using Scenario-Based Virtual Worlds in Science Education

ERIC Educational Resources Information Center

Kennedy-Clark, Shannon

2011-01-01

This paper presents the findings of a study on the current knowledge and attitudes of pre-service teachers on the use of scenario-based multi-user virtual environments in science education. The 28 participants involved in the study were introduced to "Virtual Singapura," a multi-user virtual environment, and completed an open-ended questionnaire.…

The Impact of Student Self-Efficacy on Scientific Inquiry Skills: An Exploratory Investigation in "River City," a Multi-User Virtual Environment

ERIC Educational Resources Information Center

Ketelhut, Diane Jass

2007-01-01

This exploratory study investigated data-gathering behaviors exhibited by 100 seventh-grade students as they participated in a scientific inquiry-based curriculum project delivered by a multi-user virtual environment (MUVE). This research examined the relationship between students' self-efficacy on entry into the authentic scientific activity and…

In-Pile Instrumentation Multi- Parameter System Utilizing Photonic Fibers and Nanovision

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

Burgett, Eric

2015-10-13

An advanced in-pile multi-parameter reactor monitoring system is being proposed in this funding opportunity. The proposed effort brings cutting edge, high fidelity optical measurement systems into the reactor environment in an unprecedented fashion, including in-core, in-cladding and in-fuel pellet itself. Unlike instrumented leads, the proposed system provides a unique solution to a multi-parameter monitoring need in core while being minimally intrusive in the reactor core. Detector designs proposed herein can monitor fuel compression and expansion in both the radial and axial dimensions as well as monitor linear power profiles and fission rates during the operation of the reactor. In additionmore » to pressure, stress, strain, compression, neutron flux, neutron spectra, and temperature can be observed inside the fuel bundle and fuel rod using the proposed system. The proposed research aims at developing radiation-hard, harsh-environment multi-parameter systems for insertion into the reactor environment. The proposed research holds the potential to drastically increase the fidelity and precision of in-core instrumentation with little or no impact in the neutron economy in the reactor environment while providing a measurement system capable of operation for entire operating cycles.« less

40 CFR 180.1149 - Inclusion bodies of the multi-nuclear polyhedrosis virus of Anagrapha falcifera; exemption from...

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Inclusion bodies of the multi-nuclear... Inclusion bodies of the multi-nuclear polyhedrosis virus of Anagrapha falcifera; exemption from the requirement of a tolerance. The microbial pest control agent inclusion bodies of the multi-nuclear...

Development of a Multi-Disciplinary Computing Environment (MDICE)

NASA Technical Reports Server (NTRS)

Kingsley, Gerry; Siegel, John M., Jr.; Harrand, Vincent J.; Lawrence, Charles; Luker, Joel J.

1999-01-01

The growing need for and importance of multi-component and multi-disciplinary engineering analysis has been understood for many years. For many applications, loose (or semi-implicit) coupling is optimal, and allows the use of various legacy codes without requiring major modifications. For this purpose, CFDRC and NASA LeRC have developed a computational environment to enable coupling between various flow analysis codes at several levels of fidelity. This has been referred to as the Visual Computing Environment (VCE), and is being successfully applied to the analysis of several aircraft engine components. Recently, CFDRC and AFRL/VAAC (WL) have extended the framework and scope of VCE to enable complex multi-disciplinary simulations. The chosen initial focus is on aeroelastic aircraft applications. The developed software is referred to as MDICE-AE, an extensible system suitable for integration of several engineering analysis disciplines. This paper describes the methodology, basic architecture, chosen software technologies, salient library modules, and the current status of and plans for MDICE. A fluid-structure interaction application is described in a separate companion paper.

VizieR Online Data Catalog: Interferometry and spectroscopy of sigma Orionis (Schaefer+, 2016)

NASA Astrophysics Data System (ADS)

Schaefer, G. H.; Hummel, C. A.; Gies, D. R.; Zavala, R. T.; Monnier, J. D.; Walter, F. M.; Turner, N. H.; Baron, F.; Ten Brummelaar, T.; Che, X.; Farrington, C. D.; Kraus, S.; Sturmann, J.; Sturmann, L.

2017-03-01

Interferometric data on the σ Orionis triple system were collected between 2010 and 2013 at the CHARA Array located on Mount Wilson, California. The array has six 1m telescopes arranged in a Y configuration with baselines ranging from 34 to 331m. here are two telescopes in each arm, labeled as E (East), W (West), and S (South). We used the Michigan Infrared Combiner (MIRC) to combine the light from three to six telescopes simultaneously. All data were collected after the photometric channels were installed in MIRC; the photometric channels measure the amount of light received from each telescope during the observations to improve the calibration. We used the low spectral resolution prism (R~42) to disperse the fringes across eight spectral channels in the H band (λ=1.5-1.8μm). Navy Prototype Optical Interferometer (NPOI) observations of σ Orionis were collected over a period from 2000 to 2013. Initially, the observations were obtained with the 3-beam combiner, and then, starting in 2002, with the 6-beam hybrid combiner. The NPOI beam combiners disperse the light and record the visibility spectra from 550 to 850 nm in 16 spectral channels. In total, some 59 nights of observations were executed, of which 26 nights were of good quality. The calibrators were selected from a list of single stars maintained at NPOI with diameters estimated from V and (V-K) using the surface brightness relation published by Mozurkewich et al. 2003AJ....126.2502M and van Belle et al. 2009MNRAS.394.1925V. The information for all of the calibrators is given in Table5. We obtained new spectroscopic radial velocity measurements of σ Orionis Aa,Ab using the 1.5m telescope at Cerro Tololo Inter-American Observatory (CTIO). We obtained 40 observations on 29 nights using the Fiber Echelle (FE) Spectrograph (http://www.ctio.noao.edu/~atokovin/echelle/FECH-overview.html) (R=25000, λ=4800-7000Å) between UT 2008 September 23 and 2009 February 21. Additional observations were obtained using the Chiron fiber-fed echelle spectrometer equipped with an image slicer (R=78000, λ=4550-8800Å) on 10 nights between UT 2012 November 4 and 2013 February 2 and 11 nights between UT 2016 January 21 and March 27. The Chiron observations were concentrated near the periastron passage of the close pair. The median radial velocities of σ Ori Aa and Ab, measured from the selected spectral lines, are presented in Table8. (5 data files).

Methods for radiation detection and characterization using a multiple detector probe

DOEpatents

Akers, Douglas William; Roybal, Lyle Gene

2014-11-04

Apparatuses, methods, and systems relating to radiological characterization of environments are disclosed. Multi-detector probes with a plurality of detectors in a common housing may be used to substantially concurrently detect a plurality of different radiation activities and types. Multiple multi-detector probes may be used in a down-hole environment to substantially concurrently detect radioactive activity and contents of a buried waste container. Software may process, analyze, and integrate the data from the different multi-detector probes and the different detector types therein to provide source location and integrated analysis as to the source types and activity in the measured environment. Further, the integrated data may be used to compensate for differential density effects and the effects of radiation shielding materials within the volume being measured.

Spatially extended K Iλ7699 emission in the nebula of VY CMa: kinematics and geometry

NASA Astrophysics Data System (ADS)

Smith, Nathan

2004-04-01

Long-slit echelle spectra reveal bright extended emission from the K Iλ7699 resonance line in the reflection nebula surrounding the extreme red supergiant VY Canis Majoris. The central star has long been known for its unusually bright K I emission lines, but this is the first report of intrinsic emission from K I in the nebula. The extended emission is not just a reflected spectrum of the star, but is due to resonant scattering by K atoms in the outer nebula itself, and is therefore a valuable probe of the kinematics and geometry of the circumstellar environment of VY CMa. Dramatic velocity structure is seen in the long-slit spectra, and most lines of sight through the nebula intersect multiple distinct velocity components. A faint `halo' at large distances from the star does appear to show a reflected spectrum, however, and suggests a systemic velocity of +40 km s-1 with respect to the Sun. The most striking feature is blueshifted emission from the filled interior of a large shell seen in images; the kinematic structure is reminiscent of a Hubble flow, and provides strong evidence for asymmetric and episodic mass loss due to localized eruptions on the stellar surface.

A Multi-Agent Environment for Negotiation

NASA Astrophysics Data System (ADS)

Hindriks, Koen V.; Jonker, Catholijn M.; Tykhonov, Dmytro

In this chapter we introduce the System for Analysis of Multi-Issue Negotiation (SAMIN). SAMIN offers a negotiation environment that supports and facilitates the setup of various negotiation setups. The environment has been designed to analyse negotiation processes between human negotiators, between human and software agents, and between software agents. It offers a range of different agents, different domains, and other options useful to define a negotiation setup. The environment has been used to test and evaluate a range of negotiation strategies in various domains playing against other negotiating agents as well as humans. We discuss some of the results obtained by means of these experiments.

A Summary of the Naval Postgraduate School Research Program

DTIC Science & Technology

1989-08-30

5 Fundamental Theory for Automatically Combining Changes to Software Systems ............................ 6 Database -System Approach to...Software Engineering Environments(SEE’s) .................................. 10 Multilevel Database Security .......................... 11 Temporal... Database Management and Real-Time Database Computers .................................... 12 The Multi-lingual, Multi Model, Multi-Backend Database

Design of supply chain in fuzzy environment

NASA Astrophysics Data System (ADS)

Rao, Kandukuri Narayana; Subbaiah, Kambagowni Venkata; Singh, Ganja Veera Pratap

2013-05-01

Nowadays, customer expectations are increasing and organizations are prone to operate in an uncertain environment. Under this uncertain environment, the ultimate success of the firm depends on its ability to integrate business processes among supply chain partners. Supply chain management emphasizes cross-functional links to improve the competitive strategy of organizations. Now, companies are moving from decoupled decision processes towards more integrated design and control of their components to achieve the strategic fit. In this paper, a new approach is developed to design a multi-echelon, multi-facility, and multi-product supply chain in fuzzy environment. In fuzzy environment, mixed integer programming problem is formulated through fuzzy goal programming in strategic level with supply chain cost and volume flexibility as fuzzy goals. These fuzzy goals are aggregated using minimum operator. In tactical level, continuous review policy for controlling raw material inventories in supplier echelon and controlling finished product inventories in plant as well as distribution center echelon is considered as fuzzy goals. A non-linear programming model is formulated through fuzzy goal programming using minimum operator in the tactical level. The proposed approach is illustrated with a numerical example.

The KALI multi-arm robot programming and control environment

NASA Technical Reports Server (NTRS)

Backes, Paul; Hayati, Samad; Hayward, Vincent; Tso, Kam

1989-01-01

The KALI distributed robot programming and control environment is described within the context of its use in the Jet Propulsion Laboratory (JPL) telerobot project. The purpose of KALI is to provide a flexible robot programming and control environment for coordinated multi-arm robots. Flexibility, both in hardware configuration and software, is desired so that it can be easily modified to test various concepts in robot programming and control, e.g., multi-arm control, force control, sensor integration, teleoperation, and shared control. In the programming environment, user programs written in the C programming language describe trajectories for multiple coordinated manipulators with the aid of KALI function libraries. A system of multiple coordinated manipulators is considered within the programming environment as one motion system. The user plans the trajectory of one controlled Cartesian frame associated with a motion system and describes the positions of the manipulators with respect to that frame. Smooth Cartesian trajectories are achieved through a blending of successive path segments. The manipulator and load dynamics are considered during trajectory generation so that given interface force limits are not exceeded.

Digital fabrication of multi-material biomedical objects.

PubMed

Cheung, H H; Choi, S H

2009-12-01

This paper describes a multi-material virtual prototyping (MMVP) system for modelling and digital fabrication of discrete and functionally graded multi-material objects for biomedical applications. The MMVP system consists of a DMMVP module, an FGMVP module and a virtual reality (VR) simulation module. The DMMVP module is used to model discrete multi-material (DMM) objects, while the FGMVP module is for functionally graded multi-material (FGM) objects. The VR simulation module integrates these two modules to perform digital fabrication of multi-material objects, which can be subsequently visualized and analysed in a virtual environment to optimize MMLM processes for fabrication of product prototypes. Using the MMVP system, two biomedical objects, including a DMM human spine and an FGM intervertebral disc spacer are modelled and digitally fabricated for visualization and analysis in a VR environment. These studies show that the MMVP system is a practical tool for modelling, visualization, and subsequent fabrication of biomedical objects of discrete and functionally graded multi-materials for biomedical applications. The system may be adapted to control MMLM machines with appropriate hardware for physical fabrication of biomedical objects.

Multi Car Elevator Control by using Learning Automaton

NASA Astrophysics Data System (ADS)

Shiraishi, Kazuaki; Hamagami, Tomoki; Hirata, Hironori

We study an adaptive control technique for multi car elevators (MCEs) by adopting learning automatons (LAs.) The MCE is a high performance and a near-future elevator system with multi shafts and multi cars. A strong point of the system is that realizing a large carrying capacity in small shaft area. However, since the operation is too complicated, realizing an efficient MCE control is difficult for top-down approaches. For example, “bunching up together" is one of the typical phenomenon in a simple traffic environment like the MCE. Furthermore, an adapting to varying environment in configuration requirement is a serious issue in a real elevator service. In order to resolve these issues, having an autonomous behavior is required to the control system of each car in MCE system, so that the learning automaton, as the solutions for this requirement, is supposed to be appropriate for the simple traffic control. First, we assign a stochastic automaton (SA) to each car control system. Then, each SA varies its stochastic behavior distributions for adapting to environment in which its policy is evaluated with each passenger waiting times. That is LA which learns the environment autonomously. Using the LA based control technique, the MCE operation efficiency is evaluated through simulation experiments. Results show the technique enables reducing waiting times efficiently, and we confirm the system can adapt to the dynamic environment.

Design and implementation of space physics multi-model application integration based on web

NASA Astrophysics Data System (ADS)

Jiang, Wenping; Zou, Ziming

With the development of research on space environment and space science, how to develop network online computing environment of space weather, space environment and space physics models for Chinese scientific community is becoming more and more important in recent years. Currently, There are two software modes on space physics multi-model application integrated system (SPMAIS) such as C/S and B/S. the C/S mode which is traditional and stand-alone, demands a team or workshop from many disciplines and specialties to build their own multi-model application integrated system, that requires the client must be deployed in different physical regions when user visits the integrated system. Thus, this requirement brings two shortcomings: reducing the efficiency of researchers who use the models to compute; inconvenience of accessing the data. Therefore, it is necessary to create a shared network resource access environment which could help users to visit the computing resources of space physics models through the terminal quickly for conducting space science research and forecasting spatial environment. The SPMAIS develops high-performance, first-principles in B/S mode based on computational models of the space environment and uses these models to predict "Space Weather", to understand space mission data and to further our understanding of the solar system. the main goal of space physics multi-model application integration system (SPMAIS) is to provide an easily and convenient user-driven online models operating environment. up to now, the SPMAIS have contained dozens of space environment models , including international AP8/AE8 IGRF T96 models and solar proton prediction model geomagnetic transmission model etc. which are developed by Chinese scientists. another function of SPMAIS is to integrate space observation data sets which offers input data for models online high-speed computing. In this paper, service-oriented architecture (SOA) concept that divides system into independent modules according to different business needs is applied to solve the problem of the independence of the physical space between multiple models. The classic MVC(Model View Controller) software design pattern is concerned to build the architecture of space physics multi-model application integrated system. The JSP+servlet+javabean technology is used to integrate the web application programs of space physics multi-model. It solves the problem of multi-user requesting the same job of model computing and effectively balances each server computing tasks. In addition, we also complete follow tasks: establishing standard graphical user interface based on Java Applet application program; Designing the interface between model computing and model computing results visualization; Realizing three-dimensional network visualization without plug-ins; Using Java3D technology to achieve a three-dimensional network scene interaction; Improved ability to interact with web pages and dynamic execution capabilities, including rendering three-dimensional graphics, fonts and color control. Through the design and implementation of the SPMAIS based on Web, we provide an online computing and application runtime environment of space physics multi-model. The practical application improves that researchers could be benefit from our system in space physics research and engineering applications.

A theoretical framework for negotiating the path of emergency management multi-agency coordination.

PubMed

Curnin, Steven; Owen, Christine; Paton, Douglas; Brooks, Benjamin

2015-03-01

Multi-agency coordination represents a significant challenge in emergency management. The need for liaison officers working in strategic level emergency operations centres to play organizational boundary spanning roles within multi-agency coordination arrangements that are enacted in complex and dynamic emergency response scenarios creates significant research and practical challenges. The aim of the paper is to address a gap in the literature regarding the concept of multi-agency coordination from a human-environment interaction perspective. We present a theoretical framework for facilitating multi-agency coordination in emergency management that is grounded in human factors and ergonomics using the methodology of core-task analysis. As a result we believe the framework will enable liaison officers to cope more efficiently within the work domain. In addition, we provide suggestions for extending the theory of core-task analysis to an alternate high reliability environment. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Enhancement of Cross-Cultural Communication within a Multi-Ethnic Environment: The Educational Function of the U.S. Air Force Office of Social Actions.

ERIC Educational Resources Information Center

Schnell, James A.

The U.S. Air Force attempts to minimize racial and sexual discrimination by incorporating federal laws into its infrastructure and by exercising consistent enforcement of these laws. This leads to a development of cross-cultural communication among various subcultures within a multi-ethnic environment. The Social Actions Office at each Air Force…

Creating an Effective Educational Environment for Adult Learners: A Qualitative, Multi-Case Study of Off-Campus Center Administrator's Use of Invitational Leadership

ERIC Educational Resources Information Center

McKnight, Carolyn P.

2012-01-01

This qualitative, multi-case study was designed to examine off-campus centers and their administrators in creating an effective learning environment for adult learners. Serving as the conceptual framework, invitational leadership theory is a holistic approach which nurtures the belief that everyone is intrinsically motivated and it is the leaders'…

Multi-Sensory Rooms: Comparing Effects of the Snoezelen and the Stimulus Preference Environment on the Behavior of Adults with Profound Mental Retardation

ERIC Educational Resources Information Center

Fava, Leonardo; Strauss, Kristin

2010-01-01

The present study examined whether Snoezelen and Stimulus Preference environments have differential effects on disruptive and pro-social behaviors in adults with profound mental retardation and autism. In N = 27 adults these target behaviors were recorded for a total of 20 sessions using both multi-sensory rooms. Three comparison groups were…

THE METALLICITY OF THE PLEIADES

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

Soderblom, David R.; Laskar, Tanmoy; Valenti, Jeff A.

2009-11-15

We have measured the abundances of Fe, Si, Ni, Ti, and Na in 20 Pleiades stars with T {sub eff} values near solar and with low vsin i using high-resolution, high signal-to-noise echelle spectra. We have validated our procedures by also analyzing 10 field stars of a range of temperatures and metallicities that were observed by Valenti and Fischer. Our result for the Pleiades is [Fe/H] = +0.03 {+-} 0.02 {+-} 0.05 (statistical and systematic). The average of published measurements for the Pleiades is +0.042 {+-} 0.021.

VizieR Online Data Catalog: CARMENES radial velocity curves of 7 M-dwarf (Trifonov+, 2018)

NASA Astrophysics Data System (ADS)

Trifonov, T.; Kuerster, M.; Zechmeister, M.; Tal-Or, L.; Caballero, J. A.; Quirrenbach, A.; Amado, P. J.; Ribas, I.; Reiners, A.; Reffert, S.; Dreizler, S.; Hatzes, A. P.; Kaminski, A.; Launhardt, R.; Henning, T.; Montes, D.; Bejar, V. J. S.; Mundt, R.; Pavlov, A.; Schmitt, J. H. M. M.; Seifert, W.; Morales, J. C.; Nowak, G.; Jeffers, S. V.; Rodriguez-Lopez, C.; Del Burgo, C.; Anglada-Escude, G.; Lopez-Santiago, J.; Mathar, R. J.; Ammler-von Eiff, M.; Guenther, E. W.; Barrado, D.; Gonzalez Hernandez, J. I.; Mancini, L.; Stuermer, J.; Abril, M.; Aceituno, J.; Alonso-Floriano, F. J.; Antona, R.; Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro, M.; Baroch, D.; Bauer, F. F.; Becerril, S.; Benitez, D.; Berdinas, Z. M.; Bergond, G.; Bluemcke, M.; Brinkmoeller, M.; Cano, J.; Cardenas Vazquez, M. C.; Casal, E.; Cifuentes, C.; Claret, A.; Colome, J.; Cortes-Contreras, M.; Czesla, S.; Diez-Alonso, E.; Feiz, C.; Fernandez, M.; Ferro, I. M.; Fuhrmeister, B.; Galadi-Enriquez, D.; Garcia-Piquer, A.; Garcia Vargas, M. L.; Gesa, L.; Gomez Galera, V.; Gonzalez-Peinado, R.; Groezinger, U.; Grohnert, S.; Guardia, J.; Guijarro, A.; de Guindos, E.; Gutierrez-Soto, J.; Hagen, H.-J.; Hauschildt, P. H.; Hedrosa, R. P.; Helmling, J.; Hermelo, I.; Hernandez Arabi, R.; Hernandez Castano, L.; Hernandez Hernando, F.; Herrero, E.; Huber, A.; Huke, P.; Johnson, E.; de Juan, E.; Kim, M.; Klein, R.; Klueter, J.; Klutsch, A.; Lafarga, M.; Lampon, M.; Lara, L. M.; Laun, W.; Lemke, U.; Lenzen, R.; Lopez Del Fresno, M.; Lopez-Gonzalez, J.; Lopez-Puertas, M.; Lopez Salas, J. F.; Luque, R.; Magan Madinabeitia, H.; Mall, U.; Mandel, H.; Marfil, E.; Marin Molina, J. A.; Maroto Fernandez, D.; Martin, E. L.; Martin-Ruiz, S.; Marvin, C. J.; Mirabet, E.; Moya, A.; Moreno-Raya, M. E.; Nagel, E.; Naranjo, V.; Nortmann, L.; Ofir, A.; Oreiro, R.; Palle, E.; Panduro, J.; Pascual, J.; Passegger, V. M.; Pedraz, S.; Perez-Calpena, A.; Perez Medialdea, D.; Perger, M.; Perryman, M. A. C.; Pluto, M.; Rabaza, O.; Ramon, A.; Rebolo, R.; Redondo, P.; Reinhardt, S.; Rhode, P.; Rix, H.-W.; Rodler, F.; Rodriguez, E.; Rodriguez Trinidad, A.; Rohlo, R.-R.; Rosich, A.; Sadegi, S.; Sanchez-Blanco, E.; Sanchez Carrasco, M. A.; Sanchez-Lopez, A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schaefer, S.; Schiller, J.; Schoefer, P.; Schweitzer, A.; Solano, E.; Stahl, O.; Strachan, J. B. P.; Suarez, J. C.; Tabernero, H. M.; Tala, M.; Tulloch, S. M.; Veredas, G.; Vico Linares, J. I.; Vilardel, F.; Wagner, K.; Winkler, J.; Woltho, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.

2017-10-01

The two CARMENES spectrographs are grism cross-dispersed, white pupil, echelle spectrograph working in quasi-Littrow mode using a two-beam, two-slice image slicer. The visible spectrograph covers the wavelength range from 0.52um to 1.05um with 61 orders, a resolving power of R=94600, and a mean sampling of 2.8 pixels per resolution element. The data presented in this paper were taken during the early phase of operation of the CARMENES visible-light spectrograph. (8 data files).

Optical design for a breadboard high-resolution spectrometer for SIRTF/IRS

NASA Astrophysics Data System (ADS)

Brown, Robert J.; Houck, James R.; van Cleve, Jeffrey E.

1996-11-01

The optical design of a breadboard high resolution infrared spectrometer for the IRS instrument on the SIRTF mission is discussed. The spectrometer uses a crossed echelle grating configuration to cover the spectral region from 10 to 20 micrometer with a resolving power of approximately equals 600. The all reflective spectrometer forms a nearly diffraction limited image of the two dimensional spectrum on a 128 multiplied by 128 arsenic doped silicon area array with 75 micrometer pixels. The design aspects discussed include, grating numerology, image quality, packaging and alignment philosophy.

Echelle Spectroscopy and Abundances in Ruprecht 106 and ARP 2

NASA Astrophysics Data System (ADS)

Brown, Jeffery A.; Wallerstein, George; Zucker, Daniel

1996-04-01

This is a preliminary report on abundances for two red giants each in the young globular clusters Ruprecht 106 and Pal 12. For Rup 106, we find [Fe/H] = -1.50 but almost all other elements are more deficient than iron, in reverse of the pattern in most metal-poor stars; the exception is oxygen, with [O/Fe] =~ 0.0. Pal 12 is less depleted, with [Fe/H] = -1.0, and has more nearly solar abundance ratios; we have no data on oxygen in Pal 12.

Abundancias químicas de ψ Octantis

NASA Astrophysics Data System (ADS)

Medina, M. C.; Pintado, O. I.

Se determinan las abundancias químicas de ψ Oct usando espectros obtenidos con EBASIM en CASLEO. Los valores iniciales de temperatura efectiva y gravedad superficial se calculan con la fotometría uvbyβ. Esta estrella fue estudiada por Pintado y Adelman (1996) usando espectros REOSC y Adelman y otros (1993), este último basado en espectros echelle obtenidos con el Telescopio Anglo Australiano. Comparamos nuestros resultados con los de los trabajos anteriormente mencionados, pudiéndose realizar una evaluación de la calidad de los espectros EBASIM.

Atlas of Vega: 3850-6860 Å

NASA Astrophysics Data System (ADS)

Kim, Hyun-Sook; Han, Inwoo; Valyavin, G.; Lee, Byeong-Cheol; Shimansky, V.; Galazutdinov, G. A.

2009-10-01

We present a high resolving power (λ/Δλ = 90,000) and high signal-to-noise ratio (˜700) spectral atlas of Vega covering the 3850-6860 Å wavelength range. The atlas is a result of averaging of spectra recorded with the aid of the echelle spectrograph BOES fed by the 1.8 m telescope at Bohyunsan Observatory (Korea). The atlas is provided only in machine-readable form (electronic data file) and will be available in the SIMBAD database upon publication. Based on data collected with the 1.8 m telescope operated at BOAO Observatory, Korea.

Data reductions and data quality for the high resolution spectrograph on the Southern African Large Telescope

NASA Astrophysics Data System (ADS)

Crawford, S. M.; Crause, Lisa; Depagne, Éric; Ilkiewicz, Krystian; Schroeder, Anja; Kuhn, Rudolph; Hettlage, Christian; Romero Colmenaro, Encarni; Kniazev, Alexei; Väisänen, Petri

2016-08-01

The High Resolution Spectrograph (HRS) on the Southern African Large Telescope (SALT) is a dual beam, fiber-fed echelle spectrograph providing high resolution capabilities to the SALT observing community. We describe the available data reduction tools and the procedures put in place for regular monitoring of the data quality from the spectrograph. Data reductions are carried out through the pyhrs package. The data characteristics and instrument stability are reported as part of the SALT Dashboard to help monitor the performance of the instrument.

Multi-agent framework for negotiation in a closed environment

NASA Astrophysics Data System (ADS)

Cretan, Adina; Coutinho, Carlos; Bratu, Ben; Jardim-Goncalves, Ricardo

2013-10-01

The goal of this paper is to offer support for small and medium enterprises which cannot or do not want to fulfill a big contract alone. Each organization has limited resources and in order to better accomplish a higher external demand, the managers are forced to outsource parts of their contracts even to concurrent organizations. In this concurrent environment each enterprise wants to preserve its decision autonomy and to disclose as little as possible from its business information. To describe this interaction, our approach is to define a framework for managing parallel and concurrent negotiations among independent organizations acting in the same industrial market. The complexity of our negotiation framework is done by the dynamic environment in which multi-attribute and multi-participant negotiations are racing over the same set of resources. Moreover, the proposed framework helps the organizations within the collaborative networked environment to augment their efficiency and ability to react to unforeseen situations, thus improving their market competitiveness.

Do outdoor environmental noise and atmospheric NO2 levels spatially overlap in urban areas?

PubMed

Tenailleau, Quentin M; Bernard, Nadine; Pujol, Sophie; Parmentier, Anne-Laure; Boilleaut, Mathieu; Houot, Hélène; Joly, Daniel; Mauny, Frédéric

2016-07-01

The urban environment holds numerous emission sources for air and noise pollution, creating optimum conditions for environmental multi-exposure situations. Evaluation of the joint-exposure levels is the main obstacle for multi-exposure studies and one of the biggest challenges of the next decade. The present study aims to describe the noise/NO2 multi-exposure situations in the urban environment by exploring the possible discordant and concordant situations of both exposures. Fine-scale diffusion models were developed in the European medium-sized city of Besançon (France), and a classification method was used to evaluate the multi-exposure situations in the façade perimeter of 10,825 buildings. Although correlated (Pearson's r = 0.64, p < 0.01), urban spatial distributions of the noise and NO2 around buildings do not overlap, and 30% of the buildings were considered to be discordant in terms of the noise and NO2 exposure levels. This discrepancy is spatially structured and associated with variables describing the building's environment. Our results support the presence of several co-existing, multi-exposure situations across the city impacted by both the urban morphology and the emission and diffusion/propagation phases of each pollutant. Identifying the mechanisms of discrepancy and convergence of multi-exposure situations could help improve the health risk assessment and public health. Copyright © 2016 Elsevier Ltd. All rights reserved.

Introduction to investigations of the negative corona and EHD flow in gaseous two-phase fluids

NASA Astrophysics Data System (ADS)

Jerzy, MIZERACZYK; Artur, BERENDT

2018-05-01

Research interests have recently been directed towards electrical discharges in multi-phase environments. Natural electrical discharges, such as lightning and coronas, occur in the Earth’s atmosphere, which is actually a mixture of gaseous phase (air) and suspended solid and liquid particulate matters (PMs). An example of an anthropogenic gaseous multi-phase environment is the flow of flue gas through electrostatic precipitators (ESPs), which are generally regarded as a mixture of a post-combustion gas with solid PM and microdroplets suspended in it. Electrical discharges in multi-phase environments, the knowledge of which is scarce, are becoming an attractive research subject, offering a wide variety of possible discharges and multi-phase environments to be studied. This paper is an introduction to electrical discharges in multi-phase environments. It is focused on DC negative coronas and accompanying electrohydrodynamic (EHD) flows in a gaseous two-phase fluid formed by air (a gaseous phase) and solid PM (a solid phase), run under laboratory conditions. The introduction is based on a review of the relevant literature. Two cases will be considered: the first case is of a gaseous two-phase fluid, initially motionless in a closed chamber before being subjected to a negative corona (with the needle-to-plate electrode arrangement), which afterwards induces an EHD flow in the chamber, and the second, of a gaseous two-phase fluid flowing transversely with respect to the needle-to-plate electrode axis along a chamber with a corona discharge running between the electrodes. This review-based introductory paper should be of interest to theoretical researchers and modellers in the field of negative corona discharges in single- or two-phase fluids, and for engineers who work on designing EHD devices (such as ESPs, EHD pumps, and smoke detectors).

Multi-Dimensional Optimization for Cloud Based Multi-Tier Applications

ERIC Educational Resources Information Center

Jung, Gueyoung

2010-01-01

Emerging trends toward cloud computing and virtualization have been opening new avenues to meet enormous demands of space, resource utilization, and energy efficiency in modern data centers. By being allowed to host many multi-tier applications in consolidated environments, cloud infrastructure providers enable resources to be shared among these…

An Applied-Scientific Approach to Field Assessments - Try It Out - A Field Guide for Practitioners (Une approche scientifique des evaluations de terrain - Essayer le - Un guide de terrain a destination des praticiens)

DTIC Science & Technology

2017-12-01

settings – be it field trials, field experiments, tests or evaluations . This guide is based on experience of the the NATO STO Task Group (HFM-211...practice by the Task Group. Feedback from defence colleges and Training and Evaluation staffs is highly welcomed. ES - 2 STO-TR-HFM-211 Une... evaluation programs have been setup to analyse and demonstrate the added value and effectiveness of new developments such as new operational concepts, new

Endommagement d'un composite polypropylène renforcé par des fibres de verre courtes : approche expérimentale

NASA Astrophysics Data System (ADS)

Laksimi, Abdelouahed; Bounouas, Lahsen; Benmedakhene, Salim; Azari, Zitoun; Imad, Abdellatif

To obtain good mechanical performance of the composite material, it is important to optimise the fibres ratio as well as the fibre/matrix interface quality which have influence on the damage. The main objective of this study is to determine the structural parameters influence on damage evolution concerning two types of polypropylene glass fibres composites. With a classical approach of damage mechanical theory which consists of load-unload tensile tests, acoustic emission permits to detect and follow damage mechanisms during loading. Fractographic analysis highlights the different assumptions and conclusions for this study.

Approche du Processus d'Auto-Formation Inspiree de la Methode des "Histoires de vie" dans le cadre de la Formation continuee des institutrices maternelles en Communaute francaise de Belgique (Approach to the Process of Self-Instruction Inspired by the "Life History" Method in the Framework of the Continuing Education of Preschool Teachers in the French-Speaking Community in Belgium).

ERIC Educational Resources Information Center

Brandt, Madeleine

1994-01-01

Describes a study of the use of a critical events questionnaire and "educational biography" as means of training preschool teachers to question their role as teachers; to question their relationship with children; and to liberate their consciousness. Discusses the quantitative and qualitative results of the self-evaluation processes. (AC)

Optimization of multi-environment trials for genomic selection based on crop models.

PubMed

Rincent, R; Kuhn, E; Monod, H; Oury, F-X; Rousset, M; Allard, V; Le Gouis, J

2017-08-01

We propose a statistical criterion to optimize multi-environment trials to predict genotype × environment interactions more efficiently, by combining crop growth models and genomic selection models. Genotype × environment interactions (GEI) are common in plant multi-environment trials (METs). In this context, models developed for genomic selection (GS) that refers to the use of genome-wide information for predicting breeding values of selection candidates need to be adapted. One promising way to increase prediction accuracy in various environments is to combine ecophysiological and genetic modelling thanks to crop growth models (CGM) incorporating genetic parameters. The efficiency of this approach relies on the quality of the parameter estimates, which depends on the environments composing this MET used for calibration. The objective of this study was to determine a method to optimize the set of environments composing the MET for estimating genetic parameters in this context. A criterion called OptiMET was defined to this aim, and was evaluated on simulated and real data, with the example of wheat phenology. The MET defined with OptiMET allowed estimating the genetic parameters with lower error, leading to higher QTL detection power and higher prediction accuracies. MET defined with OptiMET was on average more efficient than random MET composed of twice as many environments, in terms of quality of the parameter estimates. OptiMET is thus a valuable tool to determine optimal experimental conditions to best exploit MET and the phenotyping tools that are currently developed.

Gestion des ressources hydriques adaptee aux changements climatiques pour la production optimale d'hydroelectricite. Etude de cas: Bassin versant de la riviere Manicouagan

NASA Astrophysics Data System (ADS)

Haguma, Didier

Il est dorenavant etabli que les changements climatiques auront des repercussions sur les ressources en eau. La situation est preoccupante pour le secteur de production d'energie hydroelectrique, car l'eau constitue le moteur pour generer cette forme d'energie. Il sera important d'adapter les regles de gestion et/ou les installations des systemes hydriques, afin de minimiser les impacts negatifs et/ou pour capitaliser sur les retombees positives que les changements climatiques pourront apporter. Les travaux de la presente recherche s'interessent au developpement d'une methode de gestion des systemes hydriques qui tient compte des projections climatiques pour mieux anticiper les impacts de l'evolution du climat sur la production d'hydroelectricite et d'etablir des strategies d'adaptation aux changements climatiques. Le domaine d'etude est le bassin versant de la riviere Manicouagan situe dans la partie centrale du Quebec. Une nouvelle approche d'optimisation des ressources hydriques dans le contexte des changements climatiques est proposee. L'approche traite le probleme de la saisonnalite et de la non-stationnarite du climat d'une maniere explicite pour representer l'incertitude rattachee a un ensemble des projections climatiques. Cette approche permet d'integrer les projections climatiques dans le probleme d'optimisation des ressources en eau pour une gestion a long terme des systemes hydriques et de developper des strategies d'adaptation de ces systemes aux changements climatiques. Les resultats montrent que les impacts des changements climatiques sur le regime hydrologique du bassin de la riviere Manicouagan seraient le devancement et l'attenuation de la crue printaniere et l'augmentation du volume annuel d'apports. L'adaptation des regles de gestion du systeme hydrique engendrerait une hausse de la production hydroelectrique. Neanmoins, une perte de la performance des installations existantes du systeme hydrique serait observee a cause de l'augmentation des deversements non productibles dans le climat futur. Des strategies d'adaptation structurale ont ete analysees pour augmenter la capacite de production et la capacite d'ecoulement de certaines centrales hydroelectriques afin d'ameliorer la performance du systeme. Une analyse economique a permis de choisir les meilleures mesures d'adaptation et de determiner le moment opportun pour la mise en oeuvre de ces mesures. Les resultats de la recherche offrent aux gestionnaires des systemes hydriques un outil qui permet de mieux anticiper les consequences des changements climatiques sur la production hydroelectrique, incluant le rendement de centrales, les deversements non productibles et le moment le plus opportun pour inclure des modifications aux systemes hydriques. Mots-cles : systemes hydriques, adaptation aux changements climatiques, riviere Manicouagan

A Gradient Optimization Approach to Adaptive Multi-Robot Control

DTIC Science & Technology

2009-09-01

implemented for deploying a group of three flying robots with downward facing cameras to monitor an environment on the ground. Thirdly, the multi-robot...theoretically proven, and implemented on multi-robot platforms. Thesis Supervisor: Daniela Rus Title: Professor of Electrical Engineering and Computer...often nonlinear, and they are coupled through a network which changes over time. Thirdly, implementing multi-robot controllers requires maintaining mul

Cultural Geography Modeling and Analysis in Helmand Province

DTIC Science & Technology

2010-10-01

the application of an agent-based model called “Cultural Geography” to represent the civilian populace. This project uses a multi-agent system ...represent the civilian populace. This project uses a multi-agent system consisting of an environment, agents, objects (things), operations that can be...environments[1]. The model is patterned after the conflict eco- system described by Kilcullen[2] in an attempt to capture the complexities of irregular

Applying the Neurodynamics of Emotional Circular Causalities in Psychosocial and Cognitive Therapy using Multi-Sensory Environments: An ORBDE Case Study Analysis.

PubMed

Ryan, Janice

2017-10-01

This exploratory, evidence-based practice research study focuses on presenting a plausible mesoscopic brain dynamics hypothesis for the benefits of treating clients with psychosocial and cognitive challenges using a mindful therapeutic approach and multi-sensory environments. After an extensive neuroscientific review of the therapeutic benefits of mindfulness, a multi-sensory environment is presented as a window of therapeutic opportunity to more quickly and efficiently facilitate the neurobiological experience of becoming more mindful or conscious of self and environment. The complementary relationship between the default mode network and the executive attention network is offered as a neurobiological hypothesis that could explain positive occupational engagement pattern shifts in a case study video of a hospice client with advanced dementia during multi-sensory environment treatment. Orbital Decomposition is used for a video analysis that shows a significant behavioral pattern shift consistent with dampening of the perceptual system attractors that contribute to negative emotional circular causalities in a variety of client populations. This treatment approach may also prove to be valuable for any person who has developed circular causalities due to feelings of isolation, victimization, or abuse. A case is made for broader applications of this intervention that may positively influence perception during the information transfer and processing of hippocampal learning. Future research is called for to determine if positive affective, interpersonal, and occupational engagement pattern shifts during treatment are related to the improved default mode network-executive attention network synchrony characteristic of increased mindfulness.

Fault recovery for real-time, multi-tasking computer system

NASA Technical Reports Server (NTRS)

Hess, Richard (Inventor); Kelly, Gerald B. (Inventor); Rogers, Randy (Inventor); Stange, Kent A. (Inventor)

2011-01-01

System and methods for providing a recoverable real time multi-tasking computer system are disclosed. In one embodiment, a system comprises a real time computing environment, wherein the real time computing environment is adapted to execute one or more applications and wherein each application is time and space partitioned. The system further comprises a fault detection system adapted to detect one or more faults affecting the real time computing environment and a fault recovery system, wherein upon the detection of a fault the fault recovery system is adapted to restore a backup set of state variables.

SO2 Spectroscopy with A Tunable UV Laser

NASA Technical Reports Server (NTRS)

Morey, W. W.; Penney, C. M.; Lapp, M.

1973-01-01

A portion of the fluorescence spectrum of SO2 has been studied using a narrow wavelength doubled dye laser as the exciting source. One purpose of this study is to evaluate the use of SO2 resonance re-emission as a probe of SO2 in the atmosphere. When the SO2 is excited by light at 300.2 nm, for example, a strong reemission peak is observed which is Stokes-shifted from the incident light wavelength by the usual Raman shift (the VI symmetric vibration frequency 1150.5/cm ). The intensity of this peak is sensitive to small changes (.01 nm) in the incident wavelength. Measurements of the N2 quenching and self quenching of this re-emission have been obtained. Preliminary analysis of this data indicates that the quenching is weak but not negligible. The dye laser in our system is pumped by a pulsed N2 laser. Tuning 'and spectral narrowing are accomplished using a telescope-echelle grating combination. In a high power configuration the resulting pulses have a spectral width of about 5 x 10(exp -3) nm and a time duration of about 6 nsec. The echelle grating is rotated by a digital stepping motor, such that each step shifts the wavelength by 6 x 10(exp -4) nm. In addition to the tunable, narrow wavelength uv source and spectral analysis of the consequent re-emission, the system also provides time resolution of the re-emitted light to 6 nsec resolution. This capability is being used to study the lifetime of low pressure S02 fluorescence at different wavelengths and pressures.

GIARPS@TNG: GIANO-B and HARPS-N together for a wider wavelength range spectroscopy

NASA Astrophysics Data System (ADS)

Claudi, R.; Benatti, S.; Carleo, I.; Ghedina, A.; Guerra, J.; Micela, G.; Molinari, E.; Oliva, E.; Rainer, M.; Tozzi, A.; Baffa, C.; Baruffolo, A.; Buchschacher, N.; Cecconi, M.; Cosentino, R.; Fantinel, D.; Fini, L.; Ghinassi, F.; Giani, E.; Gonzalez, E.; Gonzalez, M.; Gratton, R.; Harutyunyan, A.; Hernandez, N.; Lodi, M.; Malavolta, L.; Maldonado, J.; Origlia, L.; Sanna, N.; Sanjuan, J.; Scuderi, S.; Seemann, U.; Sozzetti, A.; Perez Ventura, H.; Hernandez Diaz, M.; Galli, A.; Gonzalez, C.; Riverol, L.; Riverol, C.

2017-08-01

Since 2012, thanks to the installation of the high-resolution echelle spectrograph in the optical range HARPS-N, the Italian telescope TNG (La Palma) became one of the key facilities for the study of the extrasolar planets. In 2014 TNG also offered GIANO to the scientific community, providing a near-infrared (NIR) cross-dispersed echelle spectroscopy covering 0.97-2.45μm at a resolution of 50000. GIANO, although designed for direct light-feed from the telescope at the Nasmyth-B focus, was provisionally mounted on the rotating building and connected via fibers to only available interface at the Nasmyth-A focal plane. The synergy between these two instruments is particularly appealing for a wide range of science cases, especially for the search of exoplanets around young and active stars and the characterisation of their atmosphere. Through the funding scheme "WOW" (a Way to Others Worlds), the Italian National Institute for Astrophysics (INAF) proposed to position GIANO at the focal station for which it was originally designed and the simultaneous use of these spectrographs with the aim to achieve high-resolution spectroscopy in a wide wavelength range (0.383-2.45μm) obtained in a single exposure, giving rise to the project called GIARPS (GIANO-B & HARPS-N). Because of its characteristics, GIARPS can be considered the first and unique worldwide instrument providing not only high resolution in a large wavelength band, but also a high-precision radial velocity measurement both in the visible and in the NIR arm, since in the next future GIANO-B will be equipped with gas absorption cells.

Proposal for Implementing Multi-User Database (MUD) Technology in an Academic Library.

ERIC Educational Resources Information Center

Filby, A. M. Iliana

1996-01-01

Explores the use of MOO (multi-user object oriented) virtual environments in academic libraries to enhance reference services. Highlights include the development of multi-user database (MUD) technology from gaming to non-recreational settings; programming issues; collaborative MOOs; MOOs as distinguished from other types of virtual reality; audio…

Expressing Parallelism with ROOT

NASA Astrophysics Data System (ADS)

Piparo, D.; Tejedor, E.; Guiraud, E.; Ganis, G.; Mato, P.; Moneta, L.; Valls Pla, X.; Canal, P.

2017-10-01

The need for processing the ever-increasing amount of data generated by the LHC experiments in a more efficient way has motivated ROOT to further develop its support for parallelism. Such support is being tackled both for shared-memory and distributed-memory environments. The incarnations of the aforementioned parallelism are multi-threading, multi-processing and cluster-wide executions. In the area of multi-threading, we discuss the new implicit parallelism and related interfaces, as well as the new building blocks to safely operate with ROOT objects in a multi-threaded environment. Regarding multi-processing, we review the new MultiProc framework, comparing it with similar tools (e.g. multiprocessing module in Python). Finally, as an alternative to PROOF for cluster-wide executions, we introduce the efforts on integrating ROOT with state-of-the-art distributed data processing technologies like Spark, both in terms of programming model and runtime design (with EOS as one of the main components). For all the levels of parallelism, we discuss, based on real-life examples and measurements, how our proposals can increase the productivity of scientists.

Expressing Parallelism with ROOT

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

Piparo, D.; Tejedor, E.; Guiraud, E.

The need for processing the ever-increasing amount of data generated by the LHC experiments in a more efficient way has motivated ROOT to further develop its support for parallelism. Such support is being tackled both for shared-memory and distributed-memory environments. The incarnations of the aforementioned parallelism are multi-threading, multi-processing and cluster-wide executions. In the area of multi-threading, we discuss the new implicit parallelism and related interfaces, as well as the new building blocks to safely operate with ROOT objects in a multi-threaded environment. Regarding multi-processing, we review the new MultiProc framework, comparing it with similar tools (e.g. multiprocessing module inmore » Python). Finally, as an alternative to PROOF for cluster-wide executions, we introduce the efforts on integrating ROOT with state-of-the-art distributed data processing technologies like Spark, both in terms of programming model and runtime design (with EOS as one of the main components). For all the levels of parallelism, we discuss, based on real-life examples and measurements, how our proposals can increase the productivity of scientists.« less

Exploitation of Self Organization in UAV Swarms for Optimization in Combat Environments

DTIC Science & Technology

2008-03-01

behaviors and entangled hierarchy into Swarmfare [59] UAV simulation environment to include these models. • Validate this new model’s success through...Figure 4.3. The hierarchy of control emerges from the entangled hierarchy of the state relations at the simulation , swarm and rule/behaviors level...majors, major) Abstract Model Types (AMT) Figure A.1: SO Abstract Model Type Table 142 Appendix B. Simulators Comparision Name MATLAB Multi UAV MultiUAV

A framework for interactive visual analysis of heterogeneous marine data in an integrated problem solving environment

NASA Astrophysics Data System (ADS)

Liu, Shuai; Chen, Ge; Yao, Shifeng; Tian, Fenglin; Liu, Wei

2017-07-01

This paper presents a novel integrated marine visualization framework which focuses on processing, analyzing the multi-dimension spatiotemporal marine data in one workflow. Effective marine data visualization is needed in terms of extracting useful patterns, recognizing changes, and understanding physical processes in oceanography researches. However, the multi-source, multi-format, multi-dimension characteristics of marine data pose a challenge for interactive and feasible (timely) marine data analysis and visualization in one workflow. And, global multi-resolution virtual terrain environment is also needed to give oceanographers and the public a real geographic background reference and to help them to identify the geographical variation of ocean phenomena. This paper introduces a data integration and processing method to efficiently visualize and analyze the heterogeneous marine data. Based on the data we processed, several GPU-based visualization methods are explored to interactively demonstrate marine data. GPU-tessellated global terrain rendering using ETOPO1 data is realized and the video memory usage is controlled to ensure high efficiency. A modified ray-casting algorithm for the uneven multi-section Argo volume data is also presented and the transfer function is designed to analyze the 3D structure of ocean phenomena. Based on the framework we designed, an integrated visualization system is realized. The effectiveness and efficiency of the framework is demonstrated. This system is expected to make a significant contribution to the demonstration and understanding of marine physical process in a virtual global environment.

Proposed Methodology for Application of Human-like gradual Multi-Agent Q-Learning (HuMAQ) for Multi-robot Exploration

NASA Astrophysics Data System (ADS)

Narayan Ray, Dip; Majumder, Somajyoti

2014-07-01

Several attempts have been made by the researchers around the world to develop a number of autonomous exploration techniques for robots. But it has been always an important issue for developing the algorithm for unstructured and unknown environments. Human-like gradual Multi-agent Q-leaming (HuMAQ) is a technique developed for autonomous robotic exploration in unknown (and even unimaginable) environments. It has been successfully implemented in multi-agent single robotic system. HuMAQ uses the concept of Subsumption architecture, a well-known Behaviour-based architecture for prioritizing the agents of the multi-agent system and executes only the most common action out of all the different actions recommended by different agents. Instead of using new state-action table (Q-table) each time, HuMAQ uses the immediate past table for efficient and faster exploration. The proof of learning has also been established both theoretically and practically. HuMAQ has the potential to be used in different and difficult situations as well as applications. The same architecture has been modified to use for multi-robot exploration in an environment. Apart from all other existing agents used in the single robotic system, agents for inter-robot communication and coordination/ co-operation with the other similar robots have been introduced in the present research. Current work uses a series of indigenously developed identical autonomous robotic systems, communicating with each other through ZigBee protocol.

Accelerating three-dimensional FDTD calculations on GPU clusters for electromagnetic field simulation.

PubMed

Nagaoka, Tomoaki; Watanabe, Soichi

2012-01-01

Electromagnetic simulation with anatomically realistic computational human model using the finite-difference time domain (FDTD) method has recently been performed in a number of fields in biomedical engineering. To improve the method's calculation speed and realize large-scale computing with the computational human model, we adapt three-dimensional FDTD code to a multi-GPU cluster environment with Compute Unified Device Architecture and Message Passing Interface. Our multi-GPU cluster system consists of three nodes. The seven GPU boards (NVIDIA Tesla C2070) are mounted on each node. We examined the performance of the FDTD calculation on multi-GPU cluster environment. We confirmed that the FDTD calculation on the multi-GPU clusters is faster than that on a multi-GPU (a single workstation), and we also found that the GPU cluster system calculate faster than a vector supercomputer. In addition, our GPU cluster system allowed us to perform the large-scale FDTD calculation because were able to use GPU memory of over 100 GB.

Self-Tuning Fully-Connected PID Neural Network System for Distributed Temperature Sensing and Control of Instrument with Multi-Modules.

PubMed

Zhang, Zhen; Ma, Cheng; Zhu, Rong

2016-10-14

High integration of multi-functional instruments raises a critical issue in temperature control that is challenging due to its spatial-temporal complexity. This paper presents a multi-input multi-output (MIMO) self-tuning temperature sensing and control system for efficiently modulating the temperature environment within a multi-module instrument. The smart system ensures that the internal temperature of the instrument converges to a target without the need of a system model, thus making the control robust. The system consists of a fully-connected proportional-integral-derivative (PID) neural network (FCPIDNN) and an on-line self-tuning module. The experimental results show that the presented system can effectively control the internal temperature under various mission scenarios, in particular, it is able to self-reconfigure upon actuator failure. The system provides a new scheme for a complex and time-variant MIMO control system which can be widely applied for the distributed measurement and control of the environment in instruments, integration electronics, and house constructions.

Métier de sociologue, approche inductive et objet d'analyse. Brèves remarques à partir de Bourdieu.

PubMed

Hamel, Jacques

2015-05-01

This article seeks to reveal the role played by the inductive approach in sociology. Grounded Theory assumes its full importance in formulating sociological explanations. However, the theory does pose a problem, in that the "method" is not based on clearly defined operations, which remain implicit. This article attempts to show that the object of analysis-what is being analyzed-makes perceptible the operations implicitly conceived by the analyst, based on Grounded Theory. With qualitative analysis software, such as Atlas.ti, it is possible to shed light on these operations. The article is illustrated by the theory of Pierre Bourdieu and the epistemological considerations he developed as a result of his qualitative inquiry, La Misère du monde. Cet article cherche à montrer le rôle que joue l'approche inductive en sociologie. La Grounded Theory revêt son importance pour formuler l'explication sociologique. Celle-ci pose toutefois problème. En effet, la «méthode» ne repose pas sur des opérations clairement définies et celles-ci restent implicites. Dans cet article, on cherche à montrer que l'objet d'analyse-ce sur quoi porte l'analyse-rend perceptibles les opérations que l'analyste conçoit implicitement en s'appuyant sur la Grounded Theory. Les logiciels d'analyse qualitative, comme Atlas.ti, permettent d'autre part de les mettre en évidence. L'article est illustré par la théorie de Pierre Bourdieu et les considérations épistémologiques qu'a développées cet auteur à la suite de son enquête qualitative sur la Misère du monde. © 2015 Canadian Sociological Association/La Société canadienne de sociologie.

Répercussions psychosociales de la drépanocytose sur les parents d'enfants vivant à Kinshasa, République Démocratique du Congo: une étude qualitative

PubMed Central

Luboya, Evariste; Tshilonda, Jean-Christophe Bukasa; Ekila, Mathilde Bothale; Aloni, Michel Ntetani

2014-01-01

Introduction L'insuffisance des moyens de base pour le dépistage et la prise en charge de la socioculturel Africain. D'où la nécessité de réaliser un travail de mise en sens du vécu et des émotions en vue d'information et de soutien psychologique des familles des drépanocytaires. Cette étude a eu pour objectif d'identifier la nature des répercussions psychosociales de la drépanocytose chez les parents et chez les malades. Méthodes Une approche qualitative a été utilisée. Des entretiens ont été menés auprès des parents et des patients drépanocytaires. Nos résultats ont fait l'objet d'une analyse thématique articulée sur les circonstances de découvertes de la maladie, les répercussions de la maladie et la perception de la prise en charge. Résultats Nos interviews ont montré des répercussions psychosociales importantes chez les parents d'enfants drépanocytaires et de stigmatisation des difficultés d'insertion sociale et scolaire pour les enfants drépanocytaires. Ces derniers sont les grands oubliés des récits de parents. La prise en charge est uniquement médicale avec des ressources très limitées et aucun accompagnement psychologique de la famille n'est assuré. Conclusion La prise en charge de cette maladie nécessite la mise en place d'une politique de prise en charge basée sur une approche globale de la maladie. PMID:25574334

CLEW: A Cooperative Learning Environment for the Web.

ERIC Educational Resources Information Center

Ribeiro, Marcelo Blois; Noya, Ricardo Choren; Fuks, Hugo

This paper outlines CLEW (collaborative learning environment for the Web). The project combines MUD (Multi-User Dimension), workflow, VRML (Virtual Reality Modeling Language) and educational concepts like constructivism in a learning environment where students actively participate in the learning process. The MUD shapes the environment structure.…

Improved Radial Velocity Precision with a Tunable Laser Calibrator

NASA Astrophysics Data System (ADS)

Cramer, Claire; Brown, S.; Dupree, A. K.; Lykke, K. R.; Smith, A.; Szentgyorgyi, A.

2010-01-01

We present radial velocities obtained using a novel laser-based wavelength calibration technique. We have built a prototype laser calibrator for the Hectochelle spectrograph at the MMT 6.5 m telescope. The Hectochelle is a high-dispersion, fiber-fed, multi-object spectrograph capable of recording up to 240 spectra simultaneously with a resolving power of 40000. The standard wavelength calibration method makes use of spectra from thorium-argon hollow cathode lamps shining directly onto the fibers. The difference in light path between calibration and science light as well as the uneven distribution of spectral lines are believed to introduce errors of up to several hundred m/s in the wavelength scale. Our tunable laser wavelength calibrator solves these problems. The laser is bright enough for use with a dome screen, allowing the calibration light path to better match the science light path. Further, the laser is tuned in regular steps across a spectral order to generate a calibration spectrum, creating a comb of evenly-spaced lines on the detector. Using the solar spectrum reflected from the atmosphere to record the same spectrum in every fiber, we show that laser wavelength calibration brings radial velocity uncertainties down below 100 m/s. We present these results as well as an application of tunable laser calibration to stellar radial velocities determined with the infrared Ca triplet in globular clusters M15 and NGC 7492. We also suggest how the tunable laser could be useful for other instruments, including single-object, cross-dispersed echelle spectrographs, and adapted for infrared spectroscopy.

KiwiSpec - an advanced spectrograph for high resolution spectroscopy: prototype design and performance

NASA Astrophysics Data System (ADS)

Gibson, Steve; Barnes, Stuart I.; Hearnshaw, John; Nield, Kathryn; Cochrane, Dave; Grobler, Deon

2012-09-01

A new advanced high resolution spectrograph has been developed by Kiwistar Optics of Industrial Research Ltd., New Zealand. The instrument, KiwiSpec R4-100, is bench-mounted, bre-fed, compact (0.75m by 1.5m footprint), and is well-suited for small to medium-sized telescopes. The instrument makes use of several advanced concepts in high resolution spectrograph design. The basic design follows the classical white pupil concept in an asymmetric implementation and employs an R4 echelle grating illuminated by a 100mm diameter collimated beam for primary dispersion. A volume phase holographic grating (VPH) based grism is used for cross-dispersion. The design also allows for up to four camera and detector channels to allow for extended wavelength coverage at high eciency. A single channel prototype of the instrument has been built and successfully tested with a 1m telescope. Targets included various spectrophotometric standard stars and several radial velocity standard stars to measure the instrument's light throughput and radial velocity capabilities. The prototype uses a 725 lines/mm VPH grism, an off-the-shelf camera objective, and a 2k×2k CCD. As such, it covers the wavelength range from 420nm to 660nm and has a resolving power of R ≍ 40,000. Spectrophotometric and precision radial velocity results from the on-sky testing period will be reported, as well as results of laboratory-based measurements. The optical design of KiwiSpec, and the various multi-channel design options, will be presented elsewhere in these proceedings.

Application of Internal Standard Method for Several 3d-Transition Metallic Elements in Flame Atomic Absorption Spectrometry Using a Multi-wavelength High-resolution Spectrometer.

PubMed

Toya, Yusuke; Itagaki, Toshiko; Wagatsuma, Kazuaki

2017-01-01

We investigated a simultaneous internal standard method in flame atomic absorption spectrometry (FAAS), in order to better the analytical precision of 3d-transition metals contained in steel materials. For this purpose, a new spectrometer system for FAAS, comprising a bright xenon lamp as the primary radiation source and a high-resolution Echelle monochromator, was employed to measure several absorption lines at a wavelength width of ca. 0.3 nm at the same time, which enables the absorbances of an analytical line and also an internal standard line to be estimated. In considering several criteria for selecting an internal standard element and the absorption line, it could be suggested that platinum-group elements: ruthenium, rhodium, or palladium, were suitable for an internal standard element to determine the 3d-transition metal elements, such as titanium, iron, and nickel, by measuring an appropriate pair of these absorption lines simultaneously. Several variances of the absorption signal, such as a variation in aspirated amounts of sample solution and a short-period drift of the primary light source, would be corrected and thus reduced, when the absorbance ratio of the analytical line to the internal standard line was measured. In Ti-Pd, Ni-Rh, and Fe-Ru systems chosen as typical test samples, the repeatability of the signal respnses was investigated with/without the internal standard method, resulting in better precision when the internal standard method was applied in the FAAS with a nitrous oxide-acetylene flame rather than an air-acetylene flame.

Subjective scaling of mental workload in a multi-task environment

NASA Technical Reports Server (NTRS)

Daryanian, B.

1982-01-01

Those factors in a multi-task environment that contribute to the operators' "sense" of mental workload were identified. The subjective judgment as conscious experience of mental effort was decided to be the appropriate method of measurement. Thurstone's law of comparative judgment was employed in order to construct interval scales of subjective mental workload from paired comparisons data. An experimental paradigm (Simulated Multi-Task Decision-Making Environment) was employed to represent the ideal experimentally controlled environment in which human operators were asked to "attend" to different cases of Tulga's decision making tasks. Through various statistical analyses it was found that, in general, a lower number of tasks-to-be-processed per unit time (a condition associated with longer interarrival times), results in a lower mental workload, a higher consistency of judgments within a subject, a higher degree of agreement among the subjects, and larger distances between the cases on the Thurstone scale of subjective mental workload. The effects of various control variables and their interactions, and the different characteristics of the subjects on the variation of subjective mental workload are demonstrated.

Multi-filter spectrophotometry simulations

NASA Technical Reports Server (NTRS)

Callaghan, Kim A. S.; Gibson, Brad K.; Hickson, Paul

1993-01-01

To complement both the multi-filter observations of quasar environments described in these proceedings, as well as the proposed UBC 2.7 m Liquid Mirror Telescope (LMT) redshift survey, we have initiated a program of simulated multi-filter spectrophotometry. The goal of this work, still very much in progress, is a better quantitative assessment of the multiband technique as a viable mechanism for obtaining useful redshift and morphological class information from large scale multi-filter surveys.

Using Evaluation Research as a Means for Policy Analysis in a "New" Mission-Oriented Policy Context

ERIC Educational Resources Information Center

Amanatidou, Effie; Cunningham, Paul; Gök, Abdullah; Garefi, Ioanna

2014-01-01

Grand challenges stress the importance of multi-disciplinary research, a multi-actor approach in examining the current state of affairs and exploring possible solutions, multi-level governance and policy coordination across geographical boundaries and policy areas, and a policy environment for enabling change both in science and technology and in…

Cross-platform validation and analysis environment for particle physics

NASA Astrophysics Data System (ADS)

Chekanov, S. V.; Pogrebnyak, I.; Wilbern, D.

2017-11-01

A multi-platform validation and analysis framework for public Monte Carlo simulation for high-energy particle collisions is discussed. The front-end of this framework uses the Python programming language, while the back-end is written in Java, which provides a multi-platform environment that can be run from a web browser and can easily be deployed at the grid sites. The analysis package includes all major software tools used in high-energy physics, such as Lorentz vectors, jet algorithms, histogram packages, graphic canvases, and tools for providing data access. This multi-platform software suite, designed to minimize OS-specific maintenance and deployment time, is used for online validation of Monte Carlo event samples through a web interface.

The Effect of the Use of the 3-D Multi-User Virtual Environment "Second Life" on Student Motivation and Language Proficiency in Courses of Spanish as a Foreign Language

ERIC Educational Resources Information Center

Pares-Toral, Maria T.

2013-01-01

The ever increasing popularity of virtual worlds, also known as 3-D multi-user virtual environments (MUVEs) or simply virtual worlds provides language instructors with a new tool they can exploit in their courses. For now, "Second Life" is one of the most popular MUVEs used for teaching and learning, and although "Second Life"…

Alteration and Implementation of the CP/M-86 Operating System for a Multi-User Environment.

DTIC Science & Technology

1982-12-01

THE CP/M-86 OPERATING SYSTEM FOR A MULTI-USER ENVIRONMENT by Thomas V. Almquist and David S. Stevens C-, December 1982 ,LU Thesis Advisor : U. R. Kodres...tool$ 044, robo O0eA 6^900091 Approved for public release; distribution unlimited Alteration and Implementation of the CP/M-86 Operating System for a...SCIENCE IN COMPUTER SCIENCE from the NAVAL POSTGRADUATE SCHOOL December 1982 Authors: Approved by: ..... .. . . . . . . . . Thesis Advisor Second

Distribution of multi-resistant Gram-negative versus Gram-positive bacteria in the hospital inanimate environment.

PubMed

Lemmen, S W; Häfner, H; Zolldann, D; Stanzel, S; Lütticken, R

2004-03-01

We prospectively studied the difference in detection rates of multi-resistant Gram-positive and multi-resistant Gram-negative bacteria in the inanimate environment of patients harbouring these organisms. Up to 20 different locations around 190 patients were surveyed. Fifty-four patients were infected or colonized with methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant enterococci (VRE) and 136 with multi-resistant Gram-negative bacteria. The environmental detection rate for MRSA or VRE was 24.7% (174/705 samples) compared with 4.9% (89/1827 samples) for multi-resistant Gram-negative bacteria (P<0.001). Gram-positive bacteria were isolated more frequently than Gram-negatives from the hands of patients (P<0.001) and hospital personnel (P=0.1145). Environmental contamination did not differ between the intensive care units (ICUs) and the general wards (GWs), which is noteworthy because our ICUs are routinely disinfected twice a day, whereas GWs are cleaned just once a day with detergent. Current guidelines for the prevention of spread of multi-resistant bacteria in the hospital setting do not distinguish between Gram-positive and Gram-negative isolates. Our results suggest that the inanimate environment serves as a secondary source for MRSA and VRE, but less so for Gram-negative bacteria. Thus, strict contact isolation in a single room with complete barrier precautions is recommended for MRSA or VRE; however, for multi-resistant Gram-negative bacteria, contact isolation with barrier precautions for close contact but without a single room seems sufficient. This benefits not only the patients, but also the hospital by removing some of the strain placed on already over-stretched resources.

VizieR Online Data Catalog: Reflectance spectra of 12 Trojans and Hildas (Marsset+, 2014)

NASA Astrophysics Data System (ADS)

Marsset, M.; Vernazza, P.; Gourgeot, F.; Dumas, C.; Birlan, M.; Lamy, P.; Binzel, R. P.

2014-07-01

We present 17 reflectance spectra of 12 high albedo (pv>0.14) Trojans (8 objects) and Hildas (4 objects) obtained with the ESO/VLT Echelle spectrograph X-SHOOTER in the 0.3-2.2um spectral range (14 spectra) and with the NASA/IRTF spectrograph SpeX in the 0.8-2.5um spectral range (3 spectra). X-SHOOTER spectra were normalized to unity at 0.55um and SpeX spectra were normalized to unity at 2.2um . The spectra presented in this work were collected between April and December 2013. (18 data files).

VizieR Online Data Catalog: LCES HIRES/Keck radial velocity Exoplanet Survey (Butler+, 2017)

NASA Astrophysics Data System (ADS)

Butler, R. P.; Vogt, S. S.; Laughlin, G.; Burt, J. A.; Rivera, E. J.; Tuomi, M.; Teske, J.; Arriagada, P.; Diaz, M.; Holden, B.; Keiser, S.

2017-08-01

We present 60949 precision radial velocities of 1624 stars obtained over the past 20 years from the Lick-Carnegie Exoplanet Survey Team (LCES) survey with the HIgh-Resolution Echelle Spectrometer (HIRES) spectrometer on the Keck I telescope. We tabulate a list of 357 significant periodic signals that are of constant period and phase, and not coincident in period and/or phase with stellar activity indices. For this survey, the HIRES spectrometer was configured to operate at a nominal spectral resolving power of R~60000 and wavelength range of 3700-8000Å. (4 data files).

Stellar C III Emissions as a New Classification Parameter for (WC) Central Stars

NASA Technical Reports Server (NTRS)

Feibelman, W. A.

1999-01-01

We report detection of stellar C III lambda 1909 emission in International Ultraviolet Explorer (IUE) echelle spectra of early-type [WC] planetary nebula central stars (CSPNs). Additionally, stellar C III emission at lambda 2297 is observed in early- and late-type [WC) CSPNS. Inclusion of these C III features for abundance determinations may resolve a conflict of underabundance of C/O for early type [WC2] - [WC4] CSPNS. A linear dependence on stellar C III lambda 2297 equivalent widths can be used to indicate a new classification of type [WCUV] central stars.

Detection of Gaseous Methane on Pluto

NASA Technical Reports Server (NTRS)

Young, Leslie; Tokunaga, Alan; Elliot, J.; deBergh, Catherine; Owen, Tobias; Witteborn, Fred C. (Technical Monitor)

1995-01-01

We obtained Pluto's spectrum using the CSHELL echelle spectrograph at NASA's IRTF on Mauna Kea, on 25-26 May 1992, with a spectral resolution of 13,300. The spectral range (5998 - 6018 per centimeter, or 1661.8 - 1666.9 nm) includes the R(0) and the Q(1) - Q(9) lines of the 2v3 band of methane. The resulting spectrum shows the first detection of gaseous methane on Pluto, with a column height of 1.20 (sup +3.15) (sub -0.87) cm-A (3.22 (sup +8.46) (sub -2.34) x 10(exp 19) molecule per square centimeter)).

VizieR Online Data Catalog: Vi' LCs and RVs of the EB star TYC 5227-1023-1 (Traven+, 2017)

NASA Astrophysics Data System (ADS)

Traven, G.; Munari, U.; Dallaporta, S.; Zwitter, T.

2017-11-01

CCD photometry in the Landolt V and SLOAN i' bands of TYC5227-1023-1 has been obtained with ANS Collaboration telescope N.36 located in Cembra (Trento, Italy). Spectra of TYC 5227-1023-1 were secured in 2015-2016 with the Echelle+CCD spectrograph mounted on the 1.82m telescope operated by Osservatorio Astronomico di Padova atop Mt. Ekar (Asiago). Here we recall that the 3600-7400Å wavelength region is covered in 30 orders at a resolving power of 20000. (2 data files).

PEPSI, the High-Resolution Optical-IR Spectrograph for the LBT

NASA Astrophysics Data System (ADS)

Andersen, Michael; Strassmeier, Klaus; Hoffman, Axel; Woche, Manfred; Spano, Paolo

PEPSI is a high resolution fibre feed optical-IR polarimetric echelle spectrograph for the Large Binocular Telescope (LBT). PEPSI utilizes the two 8.4m LBT apertures to simultaneously record four polarization states at a resolution of 120.000. The extension of the coverage towards the IR is mainly motivated by the larger Zeeman splitting of IR lines, which would allow to study weaker/fainter magnetic structures on stars. The two optical arms, which also have an integral light mode with R up to 300.000, are under construction, while the IR arm is being designed.

VizieR Online Data Catalog: HI-selected Lyman limit systems metallicities (Lehner+, 2016)

NASA Astrophysics Data System (ADS)

Lehner, N.; O'Meara, J. M.; Howk, J. C.; Prochaska, J. X.; Fumagalli, M.

2018-04-01

All the new data presented here are from our Keck Observatory Database of Ionized Absorption toward Quasars (KODIAQ) database as part of our new KODIAQ Z survey (Lehner+ 2014, J/ApJ/788/119 ; O'Meara+ 2015, J/AJ/150/111). In short, these data were acquired with the HIgh Resolution Echelle Spectrometer (HIRES) on the Keck I telescope on Maunakea. These data were obtained by different PIs from different institutions with Keck access, and hundreds of spectra of QSOs at 0

Infrared Spectroscopy Data Reduction with ORAC-DR

NASA Astrophysics Data System (ADS)

Economou, F.; Jenness, T.; Cavanagh, B.; Wright, G. S.; Bridger, A. B.; Kerr, T. H.; Hirst, P.; Adamson, A. J.

ORAC-DR is a flexible and extensible data reduction pipeline suitable for both on-line and off-line use. Since its development it has been in use on-line at UKIRT for data from the infrared cameras UFTI and IRCAM and at JCMT for data from the sub-millimetre bolometer array SCUBA. We have now added a suite of on-line reduction recipes that produces publication quality (or nearly so) data from the CGS4 near-infrared spectrometer and the MICHELLE mid-infrared Echelle spectrometer. As an example, this paper briefly describes some pipeline features for one of the more commonly used observing modes.

SALT Spectroscopy of Evolved Massive Stars

NASA Astrophysics Data System (ADS)

Kniazev, A. Y.; Gvaramadze, V. V.; Berdnikov, L. N.

2017-06-01

Long-slit spectroscopy with the Southern African Large Telescope (SALT) of central stars of mid-infrared nebulae detected with the Spitzer Space Telescope and Wide-Field Infrared Survey Explorer (WISE) led to the discovery of numerous candidate luminous blue variables (cLBVs) and other rare evolved massive stars. With the recent advent of the SALT fiber-fed high-resolution echelle spectrograph (HRS), a new perspective for the study of these interesting objects is appeared. Using the HRS we obtained spectra of a dozen newly identified massive stars. Some results on the recently identified cLBV Hen 3-729 are presented.

Chemical composition of δ Scuti stars: 1. AO CVn, CP Boo, KW Aur

NASA Astrophysics Data System (ADS)

Galeev, A. I.; Ivanova, D. V.; Shimansky, V. V.; Bikmaev, I. F.

2012-11-01

We used high-resolution echelle spectra acquired with the 1.5-m Russian-Turkish Telescope to determine the fundamental atmospheric parameters and abundances of 30 chemical elements for three δ Scuti stars: AOCVn, CP Boo, and KWAur. The chemical compositions we find for these stars are similar to those for Am-star atmospheres, though some anomalies of up to 0.6-0.7 dex are observed for light and heavy elements. We consider the effect of the adopted stellar parameters (effective temperature, log g, microturbulent velocity) and the amplitude of pulsational variations on the derived elemental abundances.

The Evolution of Spiral Disks

NASA Astrophysics Data System (ADS)

Bershady, Matthew A.; Andersen, David R.

We report on aspects of an observational study to probe the mass assembly of large galaxy disks. In this contribution we focus on a new survey of integral-field Hα velocity-maps of nearby, face on disks. Preliminary results yield disk asymmetry amplitudes consistent with estimates based on the scatter in the local Tully-Fisher relation. We also show how the high quality of integral-field echelle spectroscopy enables determinations of kinematic inclinations to i ~20 °. This holds the promise that nearly-face-on galaxies can be included in the Tully-Fisher relation. Finally, we discuss the prospects for measuring dynamical asymmetries of distant galaxies.

Development of public science archive system of Subaro Telescope. 2

NASA Astrophysics Data System (ADS)

Yamamoto, Naotaka; Noda, Sachiyo; Taga, Masatoshi; Ozawa, Tomohiko; Horaguchi, Toshihiro; Okumura, Shin-Ichiro; Furusho, Reiko; Baba, Hajime; Yagi, Masafumi; Yasuda, Naoki; Takata, Tadafumi; Ichikawa, Shin-Ichi

2003-09-01

We report various improvements in a public science archive system, SMOKA (Subaru-Mitaka-Okayama-Kiso Archive system). We have developed a new interface to search observational data of minor bodies in the solar system. In addition, the other improvements (1) to search frames by specifying wavelength directly, (2) to find out calibration data set automatically, (3) to browse data on weather, humidity, and temperature, which provide information of image quality, (4) to provide quick-look images of OHS/CISCO and IRCS, and (5) to include the data from OAO HIDES (HIgh Dispersion Echelle Spectrograph), are also summarized.

VizieR Online Data Catalog: Spectra of KIC10661783 (Lehmann+, 2013)

NASA Astrophysics Data System (ADS)

Lehmann, H.; Southworth, J.; Tkachenko, A.; Pavlovski, K.

2013-08-01

In 2010, we obtained 26 high-resolution spectra of KIC 10661783 in seven almost consecutive nights using the Coude-echelle spectrograph at the 2-m telescope of the Thueringer Landessternwarte Tautenburg. The spectra have a resolving power of 64000 and cover the wavelength range 470-740nm. The exposure time was 30 min and the spectra have a signal-to-noise ratio of 90 on average. They were reduced using standard ESO-MIDAS packages and a routine for the calibration of the instrumental radial velocity zero-point using O2 telluric lines. (2 data files).

Partnering with Youth to Map Their Neighborhood Environments: A Multi-Layered GIS Approach

PubMed Central

Topmiller, Michael; Jacquez, Farrah; Vissman, Aaron T.; Raleigh, Kevin; Miller-Francis, Jenni

2014-01-01

Mapping approaches offer great potential for community-based participatory researchers interested in displaying youth perceptions and advocating for change. We describe a multi-layered approach for gaining local knowledge of neighborhood environments that engages youth as co-researchers and active knowledge producers. By integrating geographic information systems (GIS) with environmental audits, an interactive focus group, and sketch mapping, the approach provides a place-based understanding of physical activity resources from the situated experience of youth. Youth report safety and a lack of recreational resources as inhibiting physical activity. Maps reflecting youth perceptions aid policy-makers in making place-based improvements for youth neighborhood environments. PMID:25423245

A Logic for Inclusion of Administrative Domains and Administrators in Multi-domain Authorization

NASA Astrophysics Data System (ADS)

Iranmanesh, Zeinab; Amini, Morteza; Jalili, Rasool

Authorization policies for an administrative domain or a composition of multiple domains in multi-domain environments are determined by either one administrator or multiple administrators' cooperation. Several logic-based models for multi-domain environments' authorization have been proposed; however, they have not considered administrators and administrative domains in policies' representation. In this paper, we propose the syntax, proof theory, and semantics of a logic for multi-domain authorization policies including administrators and administrative domains. Considering administrators in policies provides the possibility of presenting composite administration having applicability in many collaborative applications. Indeed, administrators and administrative domains stated in policies can be used in authorization. The presented logic is based on modal logic and utilizes two calculi named the calculus of administrative domains and the calculus of administrators. It is also proved that the logic is sound. A case study is presented signifying the logic application in practical projects.

The constraint method: A new finite element technique. [applied to static and dynamic loads on plates

NASA Technical Reports Server (NTRS)

Tsai, C.; Szabo, B. A.

1973-01-01

An approch to the finite element method which utilizes families of conforming finite elements based on complete polynomials is presented. Finite element approximations based on this method converge with respect to progressively reduced element sizes as well as with respect to progressively increasing orders of approximation. Numerical results of static and dynamic applications of plates are presented to demonstrate the efficiency of the method. Comparisons are made with plate elements in NASTRAN and the high-precision plate element developed by Cowper and his co-workers. Some considerations are given to implementation of the constraint method into general purpose computer programs such as NASTRAN.

Quiz Making Activities Using the Multi-Mouse Quiz System in an Elementary School

ERIC Educational Resources Information Center

Zhou, Juan; Mori, Mikihiko; Ueda, Hiroshi; Kita, Hajime

2013-01-01

The Multi-Mouse Quiz System is an application used to treat quizzes in a classroom or other learning environment. The system comprises the Multi Mouse Quiz (MMQ) and MMQEditor. The MMQ is an application of Single Display Groupware (SDG), which enables multiple users to answer quizzes by connecting several mice to an ordinary computer. The…

Navigating to the Future: Understanding Common Tasks in a Multi-Campus Environment in the Dramatically Changing Acquisition World

ERIC Educational Resources Information Center

Bock, Julia; Burgos-Mira, Rosemary

2010-01-01

In the context of a diverse, multi-campus university, this study discusses historical factors and recent changes in scholarly communication and the economic impact of these changes as we seek to forge stronger cooperation among our campuses. After consulting literature, the authors found that issues relating to acquisitions of multi-campus…

Assessment and prediction of land ecological environment quality change based on remote sensing-a case study of the Dongting lake area in China

NASA Astrophysics Data System (ADS)

Hu, Wenmin; Wang, Zhongcheng; Li, Chunhua; Zhao, Jin; Li, Yi

2018-02-01

Multi-source remote sensing data is rarely used for the comprehensive assessment of land ecologic environment quality. In this study, a digital environmental model was proposed with the inversion algorithm of land and environmental factors based on the multi-source remote sensing data, and a comprehensive index (Ecoindex) was applied to reconstruct and predict the land environment quality of the Dongting Lake Area to assess the effect of human activities on the environment. The main finding was that with the decrease of Grade I and Grade II quality had a decreasing tendency in the lake area, mostly in suburbs and wetlands. Atmospheric water vapour, land use intensity, surface temperature, vegetation coverage, and soil water content were the main driving factors. The cause of degradation was the interference of multi-factor combinations, which led to positive and negative environmental agglomeration effects. Positive agglomeration, such as increased rainfall and vegetation coverage and reduced land use intensity, could increase environmental quality, while negative agglomeration resulted in the opposite. Therefore, reasonable ecological restoration measures should be beneficial to limit the negative effects and decreasing tendency, improve the land ecological environment quality and provide references for macroscopic planning by the government.

Weight gain prevention in the school worksite setting: Results of a multi-level cluster randomized trial

PubMed Central

Lemon, Stephenie C.; Wang, Monica L.; Wedick, Nicole M.; Estabrook, Barbara; Druker, Susan; Schneider, Kristin L.; Li, Wenjun; Pbert, Lori

2014-01-01

Objective To describe the effectiveness, reach and implementation of a weight gain prevention intervention among public school employees. Method A multi-level intervention was tested in a cluster randomized trial among 782 employees in 12 central Massachusetts public high schools from 2009 to 2012. The intervention targeted the nutrition and physical activity environment and policies, the social environment and individual knowledge, attitudes and skills. The intervention was compared to a materials only condition. The primary outcome measures were change in weight and body mass index (BMI) at 24-month follow-up. Implementation of physical environment, policy and social environment strategies at the school and interpersonal levels, and intervention participation at the individual level were assessed. Results At 24-month follow-up, there was a net change (difference of the difference) of −3.03 pounds (p=.04) and of −.48 BMI units (p=.05) between intervention and comparison conditions. The majority of intervention strategies were successfully implemented by all intervention schools, although establishing formal policies was challenging. Employee participation in programs targeting the physical and social environment was maintained over time. Conclusion This study supports that a multi-level intervention integrated within the organizational culture can be successfully implemented and prevent weight gain in public high school employees. PMID:24345602

Arctic Collaborative Environment: A New Multi-National Partnership for Arctic Science and Decision Support

NASA Technical Reports Server (NTRS)

Laymon, Charles A,; Kress, Martin P.; McCracken, Jeff E.; Spehn, Stephen L.; Tanner, Steve

2011-01-01

The Arctic Collaborative Environment (ACE) project is a new international partnership for information sharing to meet the challenges of addressing Arctic. The goal of ACE is to create an open source, web-based, multi-national monitoring, analysis, and visualization decision-support system for Arctic environmental assessment, management, and sustainability. This paper will describe the concept, system architecture, and data products that are being developed and disseminated among partners and independent users through remote access.

Multi-level Expression Design Language: Requirement level (MEDL-R) system evaluation

NASA Technical Reports Server (NTRS)

1980-01-01

An evaluation of the Multi-Level Expression Design Language Requirements Level (MEDL-R) system was conducted to determine whether it would be of use in the Goddard Space Flight Center Code 580 software development environment. The evaluation is based upon a study of the MEDL-R concept of requirement languages, the functions performed by MEDL-R, and the MEDL-R language syntax. Recommendations are made for changes to MEDL-R that would make it useful in the Code 580 environment.

IMPETUS - Interactive MultiPhysics Environment for Unified Simulations.

PubMed

Ha, Vi Q; Lykotrafitis, George

2016-12-08

We introduce IMPETUS - Interactive MultiPhysics Environment for Unified Simulations, an object oriented, easy-to-use, high performance, C++ program for three-dimensional simulations of complex physical systems that can benefit a large variety of research areas, especially in cell mechanics. The program implements cross-communication between locally interacting particles and continuum models residing in the same physical space while a network facilitates long-range particle interactions. Message Passing Interface is used for inter-processor communication for all simulations. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Media for 21st century--towards human communication media].

PubMed

Harashima, H

2000-05-01

Today, with the approach of the 21st century, attention is focused on multi-media communications combining computer, visual and audio technologies. This article discusses the communication media target and the technological problems constituting the nucleus of multi-media. The communication media is becoming an environment from which no one can escape. Since the media has such a great power, what is needed now is not to predict the future technologies, but to estimate the future world and take to responsibility for future environments.

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

Jensen, Colby B.; Folsom, Charles P.; Davis, Cliff B.

Experimental testing in the Multi-Static Environment Rodlet Transient Test Apparatus (SERTTA) will lead the rebirth of transient fuel testing in the United States as part of the Accident Tolerant Fuels (ATF) progam. The Multi-SERTTA is comprised of four isolated pressurized environments capable of a wide variety of working fluids and thermal conditions. Ultimately, the TREAT reactor as well as the Multi-SERTTA test vehicle serve the purpose of providing desired thermal-hydraulic boundary conditions to the test specimen. The initial ATF testing in TREAT will focus on reactivity insertion accident (RIA) events using both gas and water environments including typical PWR operatingmore » pressures and temperatures. For the water test environment, a test configuration is envisioned using the expansion tank as part of the gas-filled expansion volume seen by the test to provide additional pressure relief. The heat transfer conditions during the high energy power pulses of RIA events remains a subject of large uncertainty and great importance for fuel performance predictions. To support transient experiments, the Multi-SERTTA vehicle has been modeled using RELAP5 with a baseline test specimen composed of UO2 fuel in zircaloy cladding. The modeling results show the influence of the designs of the specimen, vehicle, and transient power pulses. The primary purpose of this work is to provide input and boundary conditions to fuel performance code BISON. Therefore, studies of parameters having influence on specimen performance during RIA transients are presented including cladding oxidation, power pulse magnitude and width, cladding-to-coolant heat fluxes, fuel-to-cladding gap, transient boiling effects (modified CHF values), etc. The results show the great flexibility and capacity of the TREAT Multi-SERTTA test vehicle to provide testing under a wide range of prototypic thermal-hydraulic conditions as never done before.« less

Retail food environments in Canada: Maximizing the impact of research, policy and practice.

PubMed

Minaker, Leia M

2016-06-09

Retail food environments are gaining national and international attention as important determinants of population dietary intake. Communities across Canada are beginning to discuss and implement programs and policies to create supportive retail food environments. Three considerations should drive the selection of food environment assessment methods: relevance (What is the problem, and how is it related to dietary outcomes?); resources (What human, time and financial resources are required to undertake an assessment?); and response (How will policy-makers find meaning out of and act on the information gained through the food environment assessment?). Ultimately, food environment assessments should be conducted in the context of stakeholder buy-in and multi-sectoral partnerships, since food environment solutions require multi-sectoral action. Partnerships between public health actors and the food and beverage industry can be challenging, especially when mandates are not aligned. Clarifying the motivations, expectations and roles of all stakeholders takes time but is important if the impact of food environment research, policy and practice is to be maximized. The articles contained in this special supplementary issue describe ongoing food environments research across Canada and fill some of the important gaps in the current body of Canadian food environments literature.

Cross-platform validation and analysis environment for particle physics

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

Chekanov, S. V.; Pogrebnyak, I.; Wilbern, D.

A multi-platform validation and analysis framework for public Monte Carlo simulation for high-energy particle collisions is discussed. The front-end of this framework uses the Python programming language, while the back-end is written in Java, which provides a multi-platform environment that can be run from a web browser and can easily be deployed at the grid sites. The analysis package includes all major software tools used in high-energy physics, such as Lorentz vectors, jet algorithms, histogram packages, graphic canvases, and tools for providing data access. This multi-platform software suite, designed to minimize OS-specific maintenance and deployment time, is used for onlinemore » validation of Monte Carlo event samples through a web interface.« less

Multiple-function multi-input/multi-output digital control and on-line analysis

NASA Technical Reports Server (NTRS)

Hoadley, Sherwood T.; Wieseman, Carol D.; Mcgraw, Sandra M.

1992-01-01

The design and capabilities of two digital controller systems for aeroelastic wind-tunnel models are described. The first allowed control of flutter while performing roll maneuvers with wing load control as well as coordinating the acquisition, storage, and transfer of data for on-line analysis. This system, which employs several digital signal multi-processor (DSP) boards programmed in high-level software languages, is housed in a SUN Workstation environment. A second DCS provides a measure of wind-tunnel safety by functioning as a trip system during testing in the case of high model dynamic response or in case the first DCS fails. The second DCS uses National Instruments LabVIEW Software and Hardware within a Macintosh environment.

CQPSO scheduling algorithm for heterogeneous multi-core DAG task model

NASA Astrophysics Data System (ADS)

Zhai, Wenzheng; Hu, Yue-Li; Ran, Feng

2017-07-01

Efficient task scheduling is critical to achieve high performance in a heterogeneous multi-core computing environment. The paper focuses on the heterogeneous multi-core directed acyclic graph (DAG) task model and proposes a novel task scheduling method based on an improved chaotic quantum-behaved particle swarm optimization (CQPSO) algorithm. A task priority scheduling list was built. A processor with minimum cumulative earliest finish time (EFT) was acted as the object of the first task assignment. The task precedence relationships were satisfied and the total execution time of all tasks was minimized. The experimental results show that the proposed algorithm has the advantage of optimization abilities, simple and feasible, fast convergence, and can be applied to the task scheduling optimization for other heterogeneous and distributed environment.

Unexpected series of regular frequency spacing of δ Scuti stars in the non-asymptotic regime - I. The methodology

DOE PAGES

Paparo, M.; Benko, J. M.; Hareter, M.; ...

2016-05-11

In this study, a sequence search method was developed to search the regular frequency spacing in δ Scuti stars through visual inspection and an algorithmic search. We searched for sequences of quasi-equally spaced frequencies, containing at least four members per sequence, in 90 δ Scuti stars observed by CoRoT. We found an unexpectedly large number of independent series of regular frequency spacing in 77 δ Scuti stars (from one to eight sequences) in the non-asymptotic regime. We introduce the sequence search method presenting the sequences and echelle diagram of CoRoT 102675756 and the structure of the algorithmic search. Four sequencesmore » (echelle ridges) were found in the 5–21 d –1 region where the pairs of the sequences are shifted (between 0.5 and 0.59 d –1) by twice the value of the estimated rotational splitting frequency (0.269 d –1). The general conclusions for the whole sample are also presented in this paper. The statistics of the spacings derived by the sequence search method, by FT (Fourier transform of the frequencies), and the statistics of the shifts are also compared. In many stars more than one almost equally valid spacing appeared. The model frequencies of FG Vir and their rotationally split components were used to formulate the possible explanation that one spacing is the large separation while the other is the sum of the large separation and the rotational frequency. In CoRoT 102675756, the two spacings (2.249 and 1.977 d –1) are in better agreement with the sum of a possible 1.710 d –1 large separation and two or one times, respectively, the value of the rotational frequency.« less

A new method for detecting velocity shifts and distortions between optical spectra

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

Evans, Tyler M.; Murphy, Michael T., E-mail: tevans@astro.swin.edu.au

2013-12-01

Recent quasar spectroscopy from the Very Large Telescope (VLT) and Keck suggests that fundamental constants may not actually be constant. To better confirm or refute this result, systematic errors between telescopes must be minimized. We present a new method to directly compare spectra of the same object and measure any velocity shifts between them. This method allows for the discovery of wavelength-dependent velocity shifts between spectra, i.e., velocity distortions, that could produce spurious detections of cosmological variations in fundamental constants. This 'direct comparison' method has several advantages over alternative techniques: it is model-independent (cf. line-fitting approaches), blind, in that spectralmore » features do not need to be identified beforehand, and it produces meaningful uncertainty estimates for the velocity shift measurements. In particular, we demonstrate that, when comparing echelle-resolution spectra with unresolved absorption features, the uncertainty estimates are reliable for signal-to-noise ratios ≳7 per pixel. We apply this method to spectra of quasar J2123–0050 observed with Keck and the VLT and find no significant distortions over long wavelength ranges (∼1050 Å) greater than ≈180 m s{sup –1}. We also find no evidence for systematic velocity distortions within echelle orders greater than 500 m s{sup –1}. Moreover, previous constraints on cosmological variations in the proton-electron mass ratio should not have been affected by velocity distortions in these spectra by more than 4.0 ± 4.2 parts per million. This technique may also find application in measuring stellar radial velocities in search of extra-solar planets and attempts to directly observe the expansion history of the universe using quasar absorption spectra.« less

Nebular and auroral emission lines of [Cl iii] in the optical spectra of planetary nebulae

PubMed Central

Keenan, Francis P.; Aller, Lawrence H.; Ramsbottom, Catherine A.; Bell, Kenneth L.; Crawford, Fergal L.; Hyung, Siek

2000-01-01

Electron impact excitation rates in Cl III, recently determined with the R-matrix code, are used to calculate electron temperature (Te) and density (Ne) emission line ratios involving both the nebular (5517.7, 5537.9 Å) and auroral (8433.9, 8480.9, 8500.0 Å) transitions. A comparison of these results with observational data for a sample of planetary nebulae, obtained with the Hamilton Echelle Spectrograph on the 3-m Shane Telescope, reveals that the R1 = I(5518 Å)/I(5538 Å) intensity ratio provides estimates of Ne in excellent agreement with the values derived from other line ratios in the echelle spectra. This agreement indicates that R1 is a reliable density diagnostic for planetary nebulae, and it also provides observational support for the accuracy of the atomic data adopted in the line ratio calculations. However the [Cl iii] 8433.9 Å line is found to be frequently blended with a weak telluric emission feature, although in those instances when the [Cl iii] intensity may be reliably measured, it provides accurate determinations of Te when ratioed against the sum of the 5518 and 5538 Å line fluxes. Similarly, the 8500.0 Å line, previously believed to be free of contamination by the Earth's atmosphere, is also shown to be generally blended with a weak telluric emission feature. The [Cl iii] transition at 8480.9 Å is found to be blended with the He i 8480.7 Å line, except in planetary nebulae that show a relatively weak He i spectrum, where it also provides reliable estimates of Te when ratioed against the nebular lines. Finally, the diagnostic potential of the near-UV [Cl iii] lines at 3344 and 3354 Å is briefly discussed. PMID:10759562

Major and minor oxide and trace element determination in silicate rocks by direct current plasma optical emission echelle spectrometry

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

Bankston, D.C.; Humphris, S.E.; Thompson, G.

1979-07-01

A technique for the determination of major concentrations of SiO/sub 2/, Al/sub 2/O/sub 3/, Fe/sub 2/O/sub 3/, MgO, CaO, Na/sub 2/O, and K/sub 2/O, minor levels of TiO/sub 2/, P/sub 2/O/sub 5/, and MnO, and trace concentrations of Ba, Cr, Cu, Ni, Sr, V, and Zn, in semi-microsamples 200 mg) of powdered whole rock, is described. Chemically diverse standard reference rocks are used both for calibration and assessment of accuracy. A lithium metaborate fusion melt of each standard or sample is dissolved in dilute HNO/sub 3/ containing Cs/sup +/ at a level of 0.2% (w/v). The resulting solution is usedmore » to perform all analyses except those for Na/sub 2/O and K/sub 2/O, which are determined in a portion of the original sample solution wherein the Cs/sup +/ concentration has been raised to 0.32% (w/v). Analyses of both portions of each sample solution are performed using an optical emission spectrometer/spectrograph equipped with an echelle monochromator and a dc argon plasma excitation source. Trace element detection limits ranged from 2 ppM for Cu to 15 ppM for Zn. A study of precision based on replicate determinations in three splits of the proposed USGS reference basalt BHVO-1 yielded the following results: (1) For analyses of the major and minor oxide constituents, values of the percent relative standard deviation (RSD) ranged from 1 for CaO, to 21 for P/sub 2/O/sub 5/. 2) For trace element determinations, values of the RSD ranged from 2 for Cu, to 19 for Zn. 2 figures, 11 tables.« less

New high-precision orbital and physical parameters of the double-lined low-mass spectroscopic binary BY Draconis

NASA Astrophysics Data System (ADS)

Hełminiak, K. G.; Konacki, M.; Muterspaugh, M. W.; Browne, S. E.; Howard, A. W.; Kulkarni, S. R.

2012-01-01

We present the most precise to date orbital and physical parameters of the well-known short period (P= 5.975 d), eccentric (e= 0.3) double-lined spectroscopic binary BY Draconis (BY Dra), a prototype of a class of late-type, active, spotted flare stars. We calculate the full spectroscopic/astrometric orbital solution by combining our precise radial velocities (RVs) and the archival astrometric measurements from the Palomar Testbed Interferometer (PTI). The RVs were derived based on the high-resolution echelle spectra taken between 2004 and 2008 with the Keck I/high-resolution echelle spectrograph, Shane/CAT/HamSpec and TNG/SARG telescopes/spectrographs using our novel iodine-cell technique for double-lined binary stars. The RVs and available PTI astrometric data spanning over eight years allow us to reach 0.2-0.5 per cent level of precision in Msin 3i and the parallax but the geometry of the orbit (i≃ 154°) hampers the absolute mass precision to 3.3 per cent, which is still an order of magnitude better than for previous studies. We compare our results with a set of Yonsei-Yale theoretical stellar isochrones and conclude that BY Dra is probably a main-sequence system more metal rich than the Sun. Using the orbital inclination and the available rotational velocities of the components, we also conclude that the rotational axes of the components are likely misaligned with the orbital angular momentum. Given BY Dra's main-sequence status, late spectral type and the relatively short orbital period, its high orbital eccentricity and probable spin-orbit misalignment are not in agreement with the tidal theory. This disagreement may possibly be explained by smaller rotational velocities of the components and the presence of a substellar mass companion to BY Dra AB.

A Decade Of Teacher Professional Development With SOFIA's EXES And TEXES

NASA Astrophysics Data System (ADS)

Hemenway, Mary Kay; Lacy, J. H.; Sneden, C.; Teacher Associates, EXES

2007-12-01

Since January 1998 central Texas grade 6-12 science and math teachers have met several times per year to learn first-hand about how a scientific instrument, the Echelon Cross Echelle Spectrograph (EXES), is being developed and built for SOFIA. In addition to learning about the technology of astronomical instrumentation, they have learned about the development of SOFIA, the scheduling and preparation for observing runs, and a wide range of astronomical topics. A typical Saturday meeting includes an update on SOFIA, EXES, and its ground-based prototype, TEXES (Texas Echelon Cross Echelle Spectrograph); one or more presentations on a science or technology topic; and a Standards-linked activity that they can carry back to use in their classrooms. A variety of guest-presenters - faculty, staff, and graduate students as well as visitors (e. g., Jackie Davidson and Alan Tokunaga) - enrich the program with their expertise. Field trips are important supplements to the program; the entire group visited Waco three times to observe the SOFIA aircraft modification while selected members have accompanied scientists to McDonald Observatory, IRTF, and Gemini for observing runs. In addition, the immediacy offered by live videoconferences with TEXES observers at IRTF and Gemini brought the participants a unique appreciation of nighttime observing at a professional observatory. The participants report their increased knowledge of astronomical concepts and of the culture of professional astronomy. By spreading the SOFIA EXES teacher program over its first decade of development, the staff has formed strong professional bonds with the participants while the participants have shared their experiences with each other. Support from USRA grant 8500-98-008 and the National Science Foundation AST-0607312 and AST- 0607708 is gratefully acknowledged.

Study of Extra-Solar Planets with the Advanced Fiber Optic Echelle

NASA Technical Reports Server (NTRS)

Noyes, Robert W.; Boyce, Joseph M. (Technical Monitor)

2002-01-01

This is the final report of NASA Grant NAG5-7505, for 'Study of Extra-solar Planets with the Advanced Fiber Optic Echelle'. This program was funded in response to our proposal submitted under NASA NRA 97-OSS-06, with a total period of performance from June 1, 1998 through Feb 28 2002. Principal Investigator is Robert W. Noyes; co-Investigators are Sylvain G. Korzennik (SAO), Peter Niserison (SAO), and Timothy M. Brown (High Altitude Observatory). Since the start of this program we have carried out more than 30 observing runs, typically of 5 to 7 days duration. We obtained a total of around 2000 usable observations of about 150 stars, where a typical observation consists of 3 exposures of 10 minutes each. Using this data base we detected thc two additional planetary companions to the star Upsilon Andromedae. This detection was made independently of, and essentially simultaneously with, a similar detection by the Berkeley group (Marcy et al): the fact that two data sets were completely independent and gave essentially the same orbital parameters for this three-planet system gave a strong confirmation of this important result. We also extended our previous detection of the planet orbiting Rho Coronae Borealis to get a better determination of its orbital eccentricity: e=0.13 +/- 0.05. We detected a new planet in orbit around the star HD 89744, with orbital period 256 days, semi-major axis 0.88 AU, eccentricity 0.70, and minimum mass m sini = 7.2 m(sub Jup). This discovery is significant because of the very high orbital eccentricity, arid also because HD 89744 has both high metallicity [Fe/H] and at the same time a low [C/Fe] abundance ratio.

Free-form reflective optics for mid-infrared camera and spectrometer on board SPICA

NASA Astrophysics Data System (ADS)

Fujishiro, Naofumi; Kataza, Hirokazu; Wada, Takehiko; Ikeda, Yuji; Sakon, Itsuki; Oyabu, Shinki

2017-11-01

SPICA (Space Infrared Telescope for Cosmology and Astrophysics) is an astronomical mission optimized for mid-and far-infrared astronomy with a cryogenically cooled 3-m class telescope, envisioned for launch in early 2020s. Mid-infrared Camera and Spectrometer (MCS) is a focal plane instrument for SPICA with imaging and spectroscopic observing capabilities in the mid-infrared wavelength range of 5-38μm. MCS consists of two relay optical modules and following four scientific optical modules of WFC (Wide Field Camera; 5'x 5' field of view, f/11.7 and f/4.2 cameras), LRS (Low Resolution Spectrometer; 2'.5 long slits, prism dispersers, f/5.0 and f/1.7 cameras, spectral resolving power R ∼ 50-100), MRS (Mid Resolution Spectrometer; echelles, integral field units by image slicer, f/3.3 and f/1.9 cameras, R ∼ 1100-3000) and HRS (High Resolution Spectrometer; immersed echelles, f/6.0 and f/3.6 cameras, R ∼ 20000-30000). Here, we present optical design and expected optical performance of MCS. Most parts of MCS optics adopt off-axis reflective system for covering the wide wavelength range of 5-38μm without chromatic aberration and minimizing problems due to changes in shapes and refractive indices of materials from room temperature to cryogenic temperature. In order to achieve the high specification requirements of wide field of view, small F-number and large spectral resolving power with compact size, we employed the paraxial and aberration analysis of off-axial optical systems (Araki 2005 [1]) which is a design method using free-form surfaces for compact reflective optics such as head mount displays. As a result, we have successfully designed compact reflective optics for MCS with as-built performance of diffraction-limited image resolution.

Unexpected series of regular frequency spacing of δ Scuti stars in the non-asymptotic regime - I. The methodology

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

Paparo, M.; Benko, J. M.; Hareter, M.

In this study, a sequence search method was developed to search the regular frequency spacing in δ Scuti stars through visual inspection and an algorithmic search. We searched for sequences of quasi-equally spaced frequencies, containing at least four members per sequence, in 90 δ Scuti stars observed by CoRoT. We found an unexpectedly large number of independent series of regular frequency spacing in 77 δ Scuti stars (from one to eight sequences) in the non-asymptotic regime. We introduce the sequence search method presenting the sequences and echelle diagram of CoRoT 102675756 and the structure of the algorithmic search. Four sequencesmore » (echelle ridges) were found in the 5–21 d –1 region where the pairs of the sequences are shifted (between 0.5 and 0.59 d –1) by twice the value of the estimated rotational splitting frequency (0.269 d –1). The general conclusions for the whole sample are also presented in this paper. The statistics of the spacings derived by the sequence search method, by FT (Fourier transform of the frequencies), and the statistics of the shifts are also compared. In many stars more than one almost equally valid spacing appeared. The model frequencies of FG Vir and their rotationally split components were used to formulate the possible explanation that one spacing is the large separation while the other is the sum of the large separation and the rotational frequency. In CoRoT 102675756, the two spacings (2.249 and 1.977 d –1) are in better agreement with the sum of a possible 1.710 d –1 large separation and two or one times, respectively, the value of the rotational frequency.« less

The EDIBLES survey II. The detectability of C60+ bands

NASA Astrophysics Data System (ADS)

Lallement, R.; Cox, N. L. J.; Cami, J.; Smoker, J.; Fahrang, A.; Elyajouri, M.; Cordiner, M. A.; Linnartz, H.; Smith, K. T.; Ehrenfreund, P.; Foing, B. H.

2018-06-01

Gas phase spectroscopic laboratory experiments for the buckminsterfullerene cation C60+ have resulted in accurate rest wavelengths for five C60+ transitions that have been compared with diffuse interstellar bands (DIBs) in the near infra-red. Detecting these in astronomical spectra is difficult because of the strong contamination of ground-based spectra by atmospheric water vapor, to the presence of weak and shallow stellar lines and/or blending with other weak DIBs. The detection of the two strong bands has been claimed by several teams, and the three additional and weaker bands have been detected in a few sources. Certain recent papers have argued against the identification of C60+ based on spectral analyses claiming (i) a large variation in the ratio of the equivalent widths of the 9632 and 9577 Å bands, (ii) a large redshift of the 9632 Å band for the Orion star HD 37022, and (iii) the non-detection of the weaker 9428 Å DIB. Here we address these three points: (i) We show that the model stellar line correction for the 9632 Å DIB overestimates the difference between the strengths of the lines in giant and dwarf star spectra, casting doubts on the conclusions about the ratio variability. (ii) Using high quality stellar spectra from the ESO Diffuse Interstellar Bands Large Exploration Survey (EDIBLES), recorded with the ESO/Paranal Ultraviolet Echelle Spectrograph (UVES) in about the same atmospheric conditions, we find no wavelength shift in the 9632 Å band toward HD 37022. (iii) Using EDIBLES spectra and data from the Echelle SpectroPolarimetric Device for the Observation of Stars (ESPaDOnS) at CFHT we show that the presence of a weak 9428 Å band cannot be ruled out, even in the same observations that a previous study claimed it was not present.

Exoplanet Transits of Stellar Active Regions

NASA Astrophysics Data System (ADS)

Giampapa, Mark S.; Andretta, Vincenzo; Covino, Elvira; Reiners, Ansgar; Esposito, Massimiliano

2018-01-01

We report preliminary results of a program to obtain high spectral- and temporal-resolution observations of the neutral helium triplet line at 1083.0 nm in transiting exoplanet systems. The principal objective of our program is to gain insight on the properties of active regions, analogous to solar plages, on late-type dwarfs by essentially using exoplanet transits as high spatial resolution probes of the stellar surface within the transit chord. The 1083 nm helium line is a particularly appropriate diagnostic of magnetized areas since it is weak in the quiet photosphere of solar-type stars but appears strongly in absorption in active regions. Therefore, during an exoplanet transit over the stellar surface, variations in its absorption equivalent width can arise that are functions of the intrinsic strength of the feature in the active region and the known relative size of the exoplanet. We utilized the Galileo Telescope and the GIANO-B near-IR echelle spectrograph to obtain 1083 nm spectra during transits in bright, well-known systems that include HD 189733, HD 209458, and HD 147506 (HAT-P-2). We also obtained simultaneous auxiliary data on the same telescope with the HARPS-N UV-Visible echelle spectrograph. We will present preliminary results from our analysis of the observed variability of the strength of the He I 1083 nm line during transits.Acknowledgements: Based on observations made with the Italian Telescopio Nazionale Galileo (TNG) operated on the island of La Palma by the Fundación Galileo Galilei of the INAF (Istituto Nazionale di Astrofisica) at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias. The NSO is operated by AURA under a cooperative agreement with the NSF.

A Bayesian Poisson-lognormal Model for Count Data for Multiple-Trait Multiple-Environment Genomic-Enabled Prediction

PubMed Central

Montesinos-López, Osval A.; Montesinos-López, Abelardo; Crossa, José; Toledo, Fernando H.; Montesinos-López, José C.; Singh, Pawan; Juliana, Philomin; Salinas-Ruiz, Josafhat

2017-01-01

When a plant scientist wishes to make genomic-enabled predictions of multiple traits measured in multiple individuals in multiple environments, the most common strategy for performing the analysis is to use a single trait at a time taking into account genotype × environment interaction (G × E), because there is a lack of comprehensive models that simultaneously take into account the correlated counting traits and G × E. For this reason, in this study we propose a multiple-trait and multiple-environment model for count data. The proposed model was developed under the Bayesian paradigm for which we developed a Markov Chain Monte Carlo (MCMC) with noninformative priors. This allows obtaining all required full conditional distributions of the parameters leading to an exact Gibbs sampler for the posterior distribution. Our model was tested with simulated data and a real data set. Results show that the proposed multi-trait, multi-environment model is an attractive alternative for modeling multiple count traits measured in multiple environments. PMID:28364037

Multi-AUV autonomous task planning based on the scroll time domain quantum bee colony optimization algorithm in uncertain environment

PubMed Central

Zhang, Rubo; Yang, Yu

2017-01-01

Research on distributed task planning model for multi-autonomous underwater vehicle (MAUV). A scroll time domain quantum artificial bee colony (STDQABC) optimization algorithm is proposed to solve the multi-AUV optimal task planning scheme. In the uncertain marine environment, the rolling time domain control technique is used to realize a numerical optimization in a narrowed time range. Rolling time domain control is one of the better task planning techniques, which can greatly reduce the computational workload and realize the tradeoff between AUV dynamics, environment and cost. Finally, a simulation experiment was performed to evaluate the distributed task planning performance of the scroll time domain quantum bee colony optimization algorithm. The simulation results demonstrate that the STDQABC algorithm converges faster than the QABC and ABC algorithms in terms of both iterations and running time. The STDQABC algorithm can effectively improve MAUV distributed tasking planning performance, complete the task goal and get the approximate optimal solution. PMID:29186166

Multi-AUV autonomous task planning based on the scroll time domain quantum bee colony optimization algorithm in uncertain environment.

PubMed

Li, Jianjun; Zhang, Rubo; Yang, Yu

2017-01-01

Research on distributed task planning model for multi-autonomous underwater vehicle (MAUV). A scroll time domain quantum artificial bee colony (STDQABC) optimization algorithm is proposed to solve the multi-AUV optimal task planning scheme. In the uncertain marine environment, the rolling time domain control technique is used to realize a numerical optimization in a narrowed time range. Rolling time domain control is one of the better task planning techniques, which can greatly reduce the computational workload and realize the tradeoff between AUV dynamics, environment and cost. Finally, a simulation experiment was performed to evaluate the distributed task planning performance of the scroll time domain quantum bee colony optimization algorithm. The simulation results demonstrate that the STDQABC algorithm converges faster than the QABC and ABC algorithms in terms of both iterations and running time. The STDQABC algorithm can effectively improve MAUV distributed tasking planning performance, complete the task goal and get the approximate optimal solution.

Application of zonal model on indoor air sensor network design

NASA Astrophysics Data System (ADS)

Chen, Y. Lisa; Wen, Jin

2007-04-01

Growing concerns over the safety of the indoor environment have made the use of sensors ubiquitous. Sensors that detect chemical and biological warfare agents can offer early warning of dangerous contaminants. However, current sensor system design is more informed by intuition and experience rather by systematic design. To develop a sensor system design methodology, a proper indoor airflow modeling approach is needed. Various indoor airflow modeling techniques, from complicated computational fluid dynamics approaches to simplified multi-zone approaches, exist in the literature. In this study, the effects of two airflow modeling techniques, multi-zone modeling technique and zonal modeling technique, on indoor air protection sensor system design are discussed. Common building attack scenarios, using a typical CBW agent, are simulated. Both multi-zone and zonal models are used to predict airflows and contaminant dispersion. Genetic Algorithm is then applied to optimize the sensor location and quantity. Differences in the sensor system design resulting from the two airflow models are discussed for a typical office environment and a large hall environment.

MAI-free performance of PMU-OFDM transceiver in time-variant environment

NASA Astrophysics Data System (ADS)

Tadjpour, Layla; Tsai, Shang-Ho; Kuo, C.-C. J.

2005-06-01

An approximately multi-user OFDM transceiver was introduced to reduce the multi-access interference (MAI ) due to the carrier frequency offset (CFO) to a negligible amount via precoding by Tsai, Lin and Kuo. In this work, we investigate the performance of this precoded multi-user (PMU) OFDM system in a time-variant channel environment. We analyze and compare the MAI effect caused by time-variant channels in the PMU-OFDM and the OFDMA systems. Generally speaking, the MAI effect consists of two parts. The first part is due to the loss of orthogonality among subchannels for all users while the second part is due to the CFO effect caused by the Doppler shift. Simulation results show that, although OFDMA outperforms the PMU-OFDM transceiver in a fast time-variant environment without CFO, PMU-OFDM outperforms OFDMA in a slow time-variant channel via the use of M/2 symmetric or anti-symmetric codewords of M Hadamard-Walsh codes.

Performance implications from sizing a VM on multi-core systems: A Data analytic application s view

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

Lim, Seung-Hwan; Horey, James L; Begoli, Edmon

In this paper, we present a quantitative performance analysis of data analytics applications running on multi-core virtual machines. Such environments form the core of cloud computing. In addition, data analytics applications, such as Cassandra and Hadoop, are becoming increasingly popular on cloud computing platforms. This convergence necessitates a better understanding of the performance and cost implications of such hybrid systems. For example, the very rst step in hosting applications in virtualized environments, requires the user to con gure the number of virtual processors and the size of memory. To understand performance implications of this step, we benchmarked three Yahoo Cloudmore » Serving Benchmark (YCSB) workloads in a virtualized multi-core environment. Our measurements indicate that the performance of Cassandra for YCSB workloads does not heavily depend on the processing capacity of a system, while the size of the data set is critical to performance relative to allocated memory. We also identi ed a strong relationship between the running time of workloads and various hardware events (last level cache loads, misses, and CPU migrations). From this analysis, we provide several suggestions to improve the performance of data analytics applications running on cloud computing environments.« less

Multi-scale Mexican spotted owl (Strix occidentalis lucida) nest/roost habitat selection in Arizona and a comparison with single-scale modeling results

Treesearch

Brad C. Timm; Kevin McGarigal; Samuel A. Cushman; Joseph L. Ganey

2016-01-01

Efficacy of future habitat selection studies will benefit by taking a multi-scale approach. In addition to potentially providing increased explanatory power and predictive capacity, multi-scale habitat models enhance our understanding of the scales at which species respond to their environment, which is critical knowledge required to implement effective...

Multi-Channel Electronically Scanned Cryogenic Pressure Sensor And Method For Making Same

NASA Technical Reports Server (NTRS)

Chapman, John J. (Inventor); Hopson, Purnell, Jr. (Inventor); Holloway, Nancy M. (Inventor)

2001-01-01

A miniature, multi-channel, electronically scanned pressure measuring device uses electrostatically bonded silicon dies in a multi-element array. These dies are bonded at specific sites on a glass, pre-patterned substrate. Thermal data is multiplexed and recorded on each individual pressure measuring diaphragm. The device functions in a cryogenic environment without the need of heaters to keep the sensor at constant temperatures.

Experiences with Interactive Multi-touch Tables

NASA Astrophysics Data System (ADS)

Fikkert, Wim; Hakvoort, Michiel; van der Vet, Paul; Nijholt, Anton

Interactive multi-touch tables can be a powerful means of communication for collaborative work as well as an engaging environment for competition. Through enticing gameplay we have evaluated user experience on competitive gameplay, collaborative work and musical expression. In addition, we report on our extensive experiences with two types of interactive multi-touch tables and we introduce a software framework that abstracts from their technical differences.

A Decision Support Framework For Science-Based, Multi-Stakeholder Deliberation: A Coral Reef Example

EPA Science Inventory

We present a decision support framework for science-based assessment and multi-stakeholder deliberation. The framework consists of two parts: a DPSIR (Drivers-Pressures-States-Impacts-Responses) analysis to identify the important causal relationships among anthropogenic environ...

Social Interactions and Games

ERIC Educational Resources Information Center

Uz, Cigdem; Cagiltay, Kursat

2015-01-01

Digital games have become popular due to great technological improvements in recent years. They have been increasingly transformed from co-located experiences into multi-played, socially oriented platforms (Herodotou, 2009). Multi-User Online Games provide the opportunity to create a social environment for friendships and strengthen the…

SmallTool - a toolkit for realizing shared virtual environments on the Internet

NASA Astrophysics Data System (ADS)

Broll, Wolfgang

1998-09-01

With increasing graphics capabilities of computers and higher network communication speed, networked virtual environments have become available to a large number of people. While the virtual reality modelling language (VRML) provides users with the ability to exchange 3D data, there is still a lack of appropriate support to realize large-scale multi-user applications on the Internet. In this paper we will present SmallTool, a toolkit to support shared virtual environments on the Internet. The toolkit consists of a VRML-based parsing and rendering library, a device library, and a network library. This paper will focus on the networking architecture, provided by the network library - the distributed worlds transfer and communication protocol (DWTP). DWTP provides an application-independent network architecture to support large-scale multi-user environments on the Internet.

Genomic Prediction Accounting for Genotype by Environment Interaction Offers an Effective Framework for Breeding Simultaneously for Adaptation to an Abiotic Stress and Performance Under Normal Cropping Conditions in Rice.

PubMed

Ben Hassen, Manel; Bartholomé, Jérôme; Valè, Giampiero; Cao, Tuong-Vi; Ahmadi, Nourollah

2018-05-09

Developing rice varieties adapted to alternate wetting and drying water management is crucial for the sustainability of irrigated rice cropping systems. Here we report the first study exploring the feasibility of breeding rice for adaptation to alternate wetting and drying using genomic prediction methods that account for genotype by environment interactions. Two breeding populations (a reference panel of 284 accessions and a progeny population of 97 advanced lines) were evaluated under alternate wetting and drying and continuous flooding management systems. The predictive ability of genomic prediction for response variables (index of relative performance and the slope of the joint regression) and for multi-environment genomic prediction models were compared. For the three traits considered (days to flowering, panicle weight and nitrogen-balance index), significant genotype by environment interactions were observed in both populations. In cross validation, predictive ability for the index was on average lower (0.31) than that of the slope of the joint regression (0.64) whatever the trait considered. Similar results were found for progeny validation. Both cross-validation and progeny validation experiments showed that the performance of multi-environment models predicting unobserved phenotypes of untested entrees was similar to the performance of single environment models with differences in predictive ability ranging from -6% to 4% depending on the trait and on the statistical model concerned. The predictive ability of multi-environment models predicting unobserved phenotypes of entrees evaluated under both water management systems outperformed single environment models by an average of 30%. Practical implications for breeding rice for adaptation to alternate wetting and drying system are discussed. Copyright © 2018, G3: Genes, Genomes, Genetics.

Evaluation of stormwater harvesting sites using multi criteria decision methodology

NASA Astrophysics Data System (ADS)

Inamdar, P. M.; Sharma, A. K.; Cook, Stephen; Perera, B. J. C.

2018-07-01

Selection of suitable urban stormwater harvesting sites and associated project planning are often complex due to spatial, temporal, economic, environmental and social factors, and related various other variables. This paper is aimed at developing a comprehensive methodology framework for evaluating of stormwater harvesting sites in urban areas using Multi Criteria Decision Analysis (MCDA). At the first phase, framework selects potential stormwater harvesting (SWH) sites using spatial characteristics in a GIS environment. In second phase, MCDA methodology is used for evaluating and ranking of SWH sites in multi-objective and multi-stakeholder environment. The paper briefly describes first phase of framework and focuses chiefly on the second phase of framework. The application of the methodology is also demonstrated over a case study comprising of the local government area, City of Melbourne (CoM), Australia for the benefit of wider water professionals engaged in this area. Nine performance measures (PMs) were identified to characterise the objectives and system performance related to the eight alternative SWH sites for the demonstration of the application of developed methodology. To reflect the stakeholder interests in the current study, four stakeholder participant groups were identified, namely, water authorities (WA), academics (AC), consultants (CS), and councils (CL). The decision analysis methodology broadly consisted of deriving PROMETHEE II rankings of eight alternative SWH sites in the CoM case study, under two distinct group decision making scenarios. The major innovation of this work is the development and application of comprehensive methodology framework that assists in the selection of potential sites for SWH, and facilitates the ranking in multi-objective and multi-stakeholder environment. It is expected that the proposed methodology will assist the water professionals and managers with better knowledge that will reduce the subjectivity in the selection and evaluation of SWH sites.

A comparative review of multi-risk modelling methodologies for climate change adaptation in mountain regions

NASA Astrophysics Data System (ADS)

Terzi, Stefano; Torresan, Silvia; Schneiderbauer, Stefan

2017-04-01

Keywords: Climate change, mountain regions, multi-risk assessment, climate change adaptation. Climate change has already led to a wide range of impacts on the environment, the economy and society. Adaptation actions are needed to cope with the impacts that have already occurred (e.g. storms, glaciers melting, floods, droughts) and to prepare for future scenarios of climate change. Mountain environment is particularly vulnerable to the climate changes due to its exposure to recent climate warming (e.g. water regime changes, thawing of permafrost) and due to the high degree of specialization of both natural and human systems (e.g. alpine species, valley population density, tourism-based economy). As a consequence, the mountain local governments are encouraged to undertake territorial governance policies to climate change, considering multi-risks and opportunities for the mountain economy and identifying the best portfolio of adaptation strategies. This study aims to provide a literature review of available qualitative and quantitative tools, methodological guidelines and best practices to conduct multi-risk assessments in the mountain environment within the context of climate change. We analyzed multi-risk modelling and assessment methods applied in alpine regions (e.g. event trees, Bayesian Networks, Agent Based Models) in order to identify key concepts (exposure, resilience, vulnerability, risk, adaptive capacity), climatic drivers, cause-effect relationships and socio-ecological systems to be integrated in a comprehensive framework. The main outcomes of the review, including a comparison of existing techniques based on different criteria (e.g. scale of analysis, targeted questions, level of complexity) and a snapshot of the developed multi-risk framework for climate change adaptation will be here presented and discussed.

Algebraic aspects of the driven dynamics in the density operator and correlation functions calculation for multi-level open quantum systems

NASA Astrophysics Data System (ADS)

Bogolubov, Nikolai N.; Soldatov, Andrey V.

2017-12-01

Exact and approximate master equations were derived by the projection operator method for the reduced statistical operator of a multi-level quantum system with finite number N of quantum eigenstates interacting with arbitrary external classical fields and dissipative environment simultaneously. It was shown that the structure of these equations can be simplified significantly if the free Hamiltonian driven dynamics of an arbitrary quantum multi-level system under the influence of the external driving fields as well as its Markovian and non-Markovian evolution, stipulated by the interaction with the environment, are described in terms of the SU(N) algebra representation. As a consequence, efficient numerical methods can be developed and employed to analyze these master equations for real problems in various fields of theoretical and applied physics. It was also shown that literally the same master equations hold not only for the reduced density operator but also for arbitrary nonequilibrium multi-time correlation functions as well under the only assumption that the system and the environment are uncorrelated at some initial moment of time. A calculational scheme was proposed to account for these lost correlations in a regular perturbative way, thus providing additional computable terms to the correspondent master equations for the correlation functions.

Multi-site pain and working conditions as predictors of work ability in a 4-year follow-up among food industry employees.

PubMed

Neupane, S; Virtanen, P; Leino-Arjas, P; Miranda, H; Siukola, A; Nygård, C-H

2013-03-01

We investigated the separate and joint effects of multi-site musculoskeletal pain and physical and psychosocial exposures at work on future work ability. A survey was conducted among employees of a Finnish food industry company in 2005 (n = 1201) and a follow-up survey in 2009 (n = 734). Information on self-assessed work ability (current work ability on a scale from 0 to 10; 7 = poor work ability), multi-site musculoskeletal pain (pain in at least two anatomical areas of four), leisure-time physical activity, body mass index and physical and psychosocial exposures was obtained by questionnaire. The separate and joint effects of multi-site pain and work exposures on work ability at follow-up, among subjects with good work ability at baseline, were assessed by logistic regression, and p-values for the interaction derived. Compared with subjects with neither multi-site pain nor adverse work exposure, multi-site pain at baseline increased the risk of poor work ability at follow-up, allowing for age, gender, occupational class, body mass index and leisure-time physical activity. The separate effects of the work exposures on work ability were somewhat smaller than those of multi-site pain. Multi-site pain had an interactive effect with work environment and awkward postures, such that no association of multi-site pain with poor work ability was seen when work environment was poor or awkward postures present. The decline in work ability connected with multi-site pain was not increased by exposure to adverse physical or psychosocial factors at work. © 2012 European Federation of International Association for the Study of Pain Chapters.

Teamwork: Education for Entrants to the Environment Professions

ERIC Educational Resources Information Center

Meehan, Barry; Thomas, Ian

2006-01-01

Numerous reports over recent years emphasise the importance of teamwork training in undergraduate programs in environment education at tertiary level. This paper describes a project undertaken by a team of final year undergraduate environment students from four faculties at RMIT University in Australia working on a multi-disciplinary environment…

The STIS MAMA status: Current detector performance

NASA Technical Reports Server (NTRS)

Danks, A. C.; Joseph, C.; Bybee, R.; Argebright, V.; Abraham, J.; Kimble, R.; Woodgate, B.

1992-01-01

The STIS (Space Telescope Imaging Spectrograph) is a second generation Hubble instrument scheduled to fly in 1997. Through a variety of modes, the instrument will provide spectral resolutions from R approximately 50 in the objective spectroscopy mode to 100,000 in the high resolution echelle mode in the wavelength region from 115 to 1000 nm. In the UV the instrument employs two MAMA (Multimode Anode Microchannel plate Arrays) 1024 by 1024 pixel detectors, which provide high DQE (Detective Quantum Efficiency), and good dynamic range and resolution. The current progress and performance of these detectors are reported, illustrating that the technology is mature and that the performance is very close to flight requirements.

High resolution spectrograph. [for LST

NASA Technical Reports Server (NTRS)

Peacock, K.

1975-01-01

The high resolution spectrograph (HRS) is designed to be used with the Large Space Telescope (LST) for the study of spectra of point and extended targets in the spectral range 110 to 410 nm. It has spectral resolutions of 1,000; 30,000; and 100,000 and has a field of view as large as 10 arc sec. The spectral range and resolution are selectable using interchangeable optical components and an echelle spectrograph is used to display a cross dispersed spectrum on the photocathode of either of 2 SEC orthicon image tubes. Provisions are included for wavelength calibration, target identification and acquisition and thermal control. The system considerations of the instrument are described.

VizieR Online Data Catalog: NiI transition probability measurements (Wood+, 2014)

NASA Astrophysics Data System (ADS)

Wood, M. P.; Lawler, J. E.; Sneden, C.; Cowan, J. J.

2014-04-01

As in much of our previous branching fraction work, this NiI branching fraction study makes use of archived FTS data from both the 1.0m Fourier Transform Spectrometer (FTS) previously at the National Solar Observatory (NSO) on Kitt Peak and the Chelsea Instruments FT500 UV FTS at Lund University in Sweden. Table 1 lists the 37 FTS spectra used in our NiI branching fraction study. All NSO spectra, raw interferograms, and header files are available in the NSO electronic archives. The 80 CCD frames of spectra from commercial Ni HCD lamps of the echelle spectrograph are listed in Table 2. (6 data files).

The Development of a 30-125 Micron Array for Airborne Astronomy

NASA Technical Reports Server (NTRS)

Mason, C. G.; Dotson, J. L.; Erickson, E. F.; Farhoomand, J.; Haas, M. R.; Koerber, C. T.; Prasad, A.; Sisson, D.; Witteborn, F. C.; DeVincenzi, Donald (Technical Monitor)

2002-01-01

The development of a 30-125 micron Ge:Sb photoconductor array for AIRES (Airborne Infra-Red Echelle Spectrometer) is described. The prototype array is a 2x24 module which can be close-stacked to provide larger two-dimensional formats. Light is focused onto each detector using a collecting cone with a 2 mm pitch. The array is read out by two Raytheon SBRC-190 cryogenic multiplexers that also provide a CTIA (capacitive transimpedance amplifier) unit cell for each detector. We discuss our results from a test series conducted to measure the array performance and to evaluate its suitability for airborne astronomy.

VizieR Online Data Catalog: Ultracool white dwarfs (Gianninas+, 2015)

NASA Astrophysics Data System (ADS)

Gianninas, A.; Curd, B.; Thorstensen, J. R.; Kilic, M.; Bergeron, P.; Andrews, J. J.; Canton, P.; Agueros, M. A.

2015-11-01

All our parallax data are from the 2.4m Hiltner telescope at Michigan-Dartmouth-MIT (MDM) Observatory on Kitt Peak, Arizona. We used a thinned SITe CCD (named 'echelle'); at the f7.5 focus, each 24um pixel subtended 0.275-arcsec, giving a field of view 9.4arcmin2. For all our parallax data, we used a 4-inch-square Kron-Cousins I-band filter, which did not vignette the CCD. Exposure times varied with the brightness of the object, but were typically a few hundred seconds. Our data were taken on numerous observing runs between 2007 and 2011. (4 data files).

A very demanding spectrometer optical design for ExoMars Mission

NASA Astrophysics Data System (ADS)

Belenguer, T.; Fernandez-Rodriguez, M.; Colombo, M.; Diaz-Catalá, E.; Sanchez-Páramo, J.

2017-11-01

The objective of this report is to present the study performed for a specially demanding solution of a spectrometer [1] design based on a transmissive holographic grating especially designed to actuate as the dispersion element. The main driver of the design has been to obtain a device with a clear reduction in mass, power and mechanical envelope with respect to the previous configuration based on a prism and/or Echelle grating. This simplification is produced mainly at expense of the waveband range. This study has been carried out by Laboratorio de Instrumentación Espacial (LINES) optical designers from Instituto Nacional de Técnica Aeroespacial (INTA).

Manganese Abundances in the Stars with Metallicities -1 <[Fe/H]< +0.3

NASA Astrophysics Data System (ADS)

Mishenina, T.; Gorbaneva, T.; Pignatari, M.; Thielemann, F.-K.; Korotin, S.

2018-01-01

We estimate the Mn abundances in the atmospheres of 247 F-G-K-type dwarf stars belonging to the thin and thick disk populations in the metallicity range -1 < [Fe/H] < +0.3. The observations were conducted using the 1.93 m telescope at Observatoire de Haute-Provence (OHP, France) equipped with the echelle type spectrographs ELODIE and SOPHIE. The abundances were derived under the LTE approximation; the synthetic spectrum for the Mn lines was computed accounting for the hyperfine structure. Starting from the results obtained, we discuss the evolution of the [Mn/Fe] ratio with respect to [Fe/H] in the galactic disk.

Waveguide image-slicers for ultrahigh resolution spectroscopy

NASA Astrophysics Data System (ADS)

Beckert, Erik; Strassmeier, Klaus G.; Woche, Manfred; Eberhardt, Ramona; Tünnermann, Andreas; Andersen, Michael

2008-07-01

Waveguide image-slicer prototypes with resolutions up to 310.000 for the fiber fed PEPSI echelle spectrograph at the LBT and single waveguide thicknesses of down to 30 μm have been manufactured. The waveguides were macroscopically prepared, stacked up to an order of 7 and thinned back to square stack cross sections. A high filling ratio was achieved by realizing homogenous adhesive gaps of 4.6 μm, using index matching adhesives for TIR within the waveguides. The image-slicer stacks can be used in immersion mode and are miniaturized to be implemented in a set of four, measurements indicate an overall efficiency of above 80% for them.

Lithium in M67

NASA Technical Reports Server (NTRS)

Hobbs, L. M.; Pilachowski, Catherine

1986-01-01

Echelle spectra recorded at the Li I 6707-A line are reported for seven main-sequence members and one cool subgiant in M67. The spectral types of the seven dwarfs studied range from about F8 at the turnoff point to about G5. The principal result is that the average lithium abundance in the three hottest main-sequence stars is 0.45 x 10 to the -9th. Any enrichment of lithium in the gas of the Galactic disk in the last 5 Gyr therefore has not exceeded a factor of about two and probably is entirely negligible, when the corresponding results for NGC 752 and the Hyades are taken into account.

The SPM Kinematic Catalogue of Planetary Nebulae

NASA Astrophysics Data System (ADS)

López, J. A.; Richer, M. G.; Riesgo, H.; Steffen, W.; García-Segura, G.; Meaburn, J.; Bryce, M.

The San Pedro Mártir Kinematic Catalogue of Planetary Nebulae aims at providing detailed kinematic information for galactic planetary nebulae (PNe) and bright PNe in the Local Group. The database provides long-slit, Echelle spectra and images where the location of the slits on the nebula are indicated. As a tool to help interpret the 2D line profiles or position-velocity data, an atlas of synthetic emission line spectra accompanies the Catalogue. The atlas has been produced with the code SHAPE and contains synthetic spectra for all the main morphological groups for a wide range of spatial orientations and slit locations over the nebula.

An IUE's eye view of cool-star outer atmospheres

NASA Technical Reports Server (NTRS)

Ayres, T. R.

1981-01-01

Three topics are discussed which together demonstrate the power of the IUE to probe the occurrences of chromospheres and coronas in the cool half of the HR diagram. These are: (1) the complementary low dispersion and echelle observing modes; (2) Mg II h and k: chromospheric cooling and width luminosity correlation; and (3) empirical correlations among chromospheric, transition region, and coronal emission. The spectra of alpha Centauri (G2 V + K1 V) and Capella (G6 III + F9 III) are compared with that of the Sun and recent low dispersion surveys of cool star emission in the 1150 A to 2000 A short wavelength region are summarized.

Achieving the resolution of the spectrograph of the 6m large Azimuthal telescope

NASA Astrophysics Data System (ADS)

Sazonenko, Dmitrii; Kukushkin, Dmitrii; Bakholdin, Alexey; Valyavin, Gennady

2016-08-01

Special Astrophysical Observatory of Russian Academy of Sciences (SAO RAS) creates a spectrograph with high spectral resolution for the 6-meter telescope. The spectrograph consists of a mobile unit located at the focus of the telescope's main mirror, a stationary part located under the telescope and optical fibers which transmit light from the mobile part to the stationary one. The spectral resolution of the stationary part should be R=100000. To achieve such a value, the scheme has two spectral elements, with cross-dispersion. The main spectral element is an echelle grating. The second spectral element is a prism with a diffraction grating on one facet.

Research on multi-user encrypted search scheme in cloud environment

NASA Astrophysics Data System (ADS)

Yu, Zonghua; Lin, Sui

2017-05-01

Aiming at the existing problems of multi-user encrypted search scheme in cloud computing environment, a basic multi-user encrypted scheme is proposed firstly, and then the basic scheme is extended to an anonymous hierarchical management authority. Compared with most of the existing schemes, the scheme not only to achieve the protection of keyword information, but also to achieve the protection of user identity privacy; the same time, data owners can directly control the user query permissions, rather than the cloud server. In addition, through the use of a special query key generation rules, to achieve the hierarchical management of the user's query permissions. The safety analysis shows that the scheme is safe and that the performance analysis and experimental data show that the scheme is practicable.

Relating Narrative, Inquiry, and Inscriptions: Supporting Consequential Play

NASA Astrophysics Data System (ADS)

Barab, Sasha A.; Sadler, Troy D.; Heiselt, Conan; Hickey, Daniel; Zuiker, Steven

2007-02-01

In this paper we describe our research using a multi-user virtual environment, Quest Atlantis, to embed fourth grade students in an aquatic habitat simulation. Specifically targeted towards engaging students in a rich inquiry investigation, we layered a socio-scientific narrative and an interactive rule set into a multi-user virtual environment gaming engine to establish a virtual world through which students learned about science inquiry, water quality concepts, and the challenges in balancing scientific and socio-economic factors. Overall, students were clearly engaged, participated in rich scientific discourse, submitted quality work, and learned science content. Further, through participation in this narrative, students developed a rich perceptual, conceptual, and ethical understanding of science. This study suggests that multi-user virtual worlds can be effectively leveraged to support academic content learning.

Erratum to: Relating Narrative, Inquiry, and Inscriptions: Supporting Consequential Play

NASA Astrophysics Data System (ADS)

Barab, Sasha A.; Sadler, Troy D.; Heiselt, Conan; Hickey, Daniel; Zuiker, Steven

2010-08-01

In this paper we describe our research using a multi-user virtual environment, Quest Atlantis, to embed fourth grade students in an aquatic habitat simulation. Specifically targeted towards engaging students in a rich inquiry investigation, we layered a socio-scientific narrative and an interactive rule set into a multi-user virtual environment gaming engine to establish a virtual world through which students learned about science inquiry, water quality concepts, and the challenges in balancing scientific and socio-economic factors. Overall, students were clearly engaged, participated in rich scientific discourse, submitted quality work, and learned science content. Further, through participation in this narrative, students developed a rich perceptual, conceptual, and ethical understanding of science. This study suggests that multi-user virtual worlds can be effectively leveraged to support academic content learning.

Sensei: A Multi-Modal Framework for Assessing Stress Resiliency

DTIC Science & Technology

2013-04-30

DATE MAY2013 2. REPORT TYPE 4. TITLE AND SUBTITLE Sensei: A Multi-Modal Framework for Assessing Stress Resiliency 6. AUTHOR(S) 7. PERFORMING...Report: Distribution A Page 1 of 3 SRI International (Sarnoff) Document Sensei: A Multi-Modal Framework for Assessing Stress Resiliency (April... Stress Markers in Real-Time in Lab Environment with graded exposure to ICT’s scenarios MAC 1-6 During this reporting period, we established

Multimedia-modeling integration development environment

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

Pelton, Mitchell A.; Hoopes, Bonnie L.

2002-09-02

There are many framework systems available; however, the purpose of the framework presented here is to capitalize on the successes of the Framework for Risk Analysis in Multimedia Environmental Systems (FRAMES) and Multi-media Multi-pathway Multi-receptor Risk Assessment (3MRA) methodology as applied to the Hazardous Waste Identification Rule (HWIR) while focusing on the development of software tools to simplify the module developer?s effort of integrating a module into the framework.

Multi-Agent Framework for Virtual Learning Spaces.

ERIC Educational Resources Information Center

Sheremetov, Leonid; Nunez, Gustavo

1999-01-01

Discussion of computer-supported collaborative learning, distributed artificial intelligence, and intelligent tutoring systems focuses on the concept of agents, and describes a virtual learning environment that has a multi-agent system. Describes a model of interactions in collaborative learning and discusses agents for Web-based virtual…

Multi-objective optimization of riparian buffer networks; valuing present and future benefits

EPA Science Inventory

Multi-objective optimization has emerged as a popular approach to support water resources planning and management. This approach provides decision-makers with a suite of management options which are generated based on metrics that represent different social, economic, and environ...

Exchange of Surfactant by Natural Organic Matter on the Surfaces of Multi-Walled Carbon Nanotubes

EPA Science Inventory

The increasing production and applications of multi-walled carbon nanotubes (MWCNTs) have elicited concerns regarding their release and potential adverse effects in the environment. To form stable aqueous MWCNTs suspensions, surfactants are often employed to facilitate dispersion...

Cryptanalysis and improvement of a biometrics-based authentication and key agreement scheme for multi-server environments.

PubMed

Yang, Li; Zheng, Zhiming

2018-01-01

According to advancements in the wireless technologies, study of biometrics-based multi-server authenticated key agreement schemes has acquired a lot of momentum. Recently, Wang et al. presented a three-factor authentication protocol with key agreement and claimed that their scheme was resistant to several prominent attacks. Unfortunately, this paper indicates that their protocol is still vulnerable to the user impersonation attack, privileged insider attack and server spoofing attack. Furthermore, their protocol cannot provide the perfect forward secrecy. As a remedy of these aforementioned problems, we propose a biometrics-based authentication and key agreement scheme for multi-server environments. Compared with various related schemes, our protocol achieves the stronger security and provides more functionality properties. Besides, the proposed protocol shows the satisfactory performances in respect of storage requirement, communication overhead and computational cost. Thus, our protocol is suitable for expert systems and other multi-server architectures. Consequently, the proposed protocol is more appropriate in the distributed networks.

Cryptanalysis and improvement of a biometrics-based authentication and key agreement scheme for multi-server environments

PubMed Central

Zheng, Zhiming

2018-01-01

According to advancements in the wireless technologies, study of biometrics-based multi-server authenticated key agreement schemes has acquired a lot of momentum. Recently, Wang et al. presented a three-factor authentication protocol with key agreement and claimed that their scheme was resistant to several prominent attacks. Unfortunately, this paper indicates that their protocol is still vulnerable to the user impersonation attack, privileged insider attack and server spoofing attack. Furthermore, their protocol cannot provide the perfect forward secrecy. As a remedy of these aforementioned problems, we propose a biometrics-based authentication and key agreement scheme for multi-server environments. Compared with various related schemes, our protocol achieves the stronger security and provides more functionality properties. Besides, the proposed protocol shows the satisfactory performances in respect of storage requirement, communication overhead and computational cost. Thus, our protocol is suitable for expert systems and other multi-server architectures. Consequently, the proposed protocol is more appropriate in the distributed networks. PMID:29534085

EPA Leadership in the Global Mercury Partnership

EPA Pesticide Factsheets

The Global Mercury Partnership is a voluntary multi-stakeholder partnership initiated in 2005 to take immediate actions to protect human health and the environment from the releases of mercury and its compounds to the environment.

MULTI: a shared memory approach to cooperative molecular modeling.

PubMed

Darden, T; Johnson, P; Smith, H

1991-03-01

A general purpose molecular modeling system, MULTI, based on the UNIX shared memory and semaphore facilities for interprocess communication is described. In addition to the normal querying or monitoring of geometric data, MULTI also provides processes for manipulating conformations, and for displaying peptide or nucleic acid ribbons, Connolly surfaces, close nonbonded contacts, crystal-symmetry related images, least-squares superpositions, and so forth. This paper outlines the basic techniques used in MULTI to ensure cooperation among these specialized processes, and then describes how they can work together to provide a flexible modeling environment.

Long-term Spectroscopic and Photometric Monitoring of Bright Interacting Algol-type Binary Stars

NASA Astrophysics Data System (ADS)

Reed, Phillip A.

2018-01-01

Binary stars have long been used as natural laboratories for studying such fundamental stellar properties as mass. Interacting binaries allow us to examine more complicated aspects such as mass flow between stars, accretion processes, magnetic fields, and stellar mergers. Algol-type interacting binary stars -- consisting of a cool giant or sub-giant donating mass to a much hotter, less evolved, and more massive main-sequence companion -- undergo steady mass transfer and have been used to measure mass transfer rates and to test stellar evolution theories. The method of back-projection Doppler tomography has also been applied to interacting Algols and has produced indirect velocity-space images of the accretion structures (gas streams, accretion disks, etc.) derived from spectroscopic observations of hydrogen and helium emission lines. The accretion structures in several Algol systems have actually been observed to change between disk-like states and stream-like states on timescales as short as several orbital cycles (Richards et al., 2014). Presented here are the first results from a project aimed at studying bright interacting Algol systems with simultaneous mid-resolution (11,000

Absolute Dimensions and Evolutionary Status of the Semi-detached Algol W Ursae Minoris

NASA Astrophysics Data System (ADS)

Park, Jang-Ho; Hong, Kyeongsoo; Koo, Jae-Rim; Lee, Jae Woo; Kim, Chun-Hwey

2018-03-01

Double-lined eclipsing binaries allow accurate and direct determination of fundamental parameters such as mass and radius for each component, and they provide important constraints on the stellar structure and evolution models. In this study, we aim to determine a unique set of binary parameters for the Algol system W UMi and to examine its evolutionary status. New high-resolution time-series spectroscopic observations were carried out during 14 nights from 2008 April to 2011 March, and a total of 37 spectra were obtained using the Bohyunsan Optical Echelle Spectrograph. We measured the radial velocities (RVs) for both components, and the effective temperature of the primary star was found to be T eff,1 = 9310 ± 90 K by a comparison of the observed spectra and the Kurucz models. The physical parameters of W UMi were derived by an analysis of our RV data together with the multi-band light curves of Devinney et al. The individual masses, radii, and luminosities of both components are M 1 = 3.68 ± 0.10 M ⊙ and M 2 = 1.47 ± 0.04 M ⊙, R 1 = 3.88 ± 0.03 R ⊙ and R 2 = 3.13 ± 0.03 R ⊙, and L 1 = 102 ± 1 L ⊙ and L 2 = 7.3 ± 0.1 L ⊙, respectively. A comparison of these parameters with theoretical stellar models showed that the primary component lies in the main-sequence band, while the less massive secondary is noticeably evolved. The results indicate that the initially more massive star became the present secondary by losing most of its own mass via mass transfer to the companion (present primary).

Multi-year assimilation of IASI and MLS ozone retrievals: variability of tropospheric ozone over the tropics in response to ENSO

NASA Astrophysics Data System (ADS)

Peiro, Hélène; Emili, Emanuele; Cariolle, Daniel; Barret, Brice; Le Flochmoën, Eric

2018-05-01

The Infrared Atmospheric Sounder Instrument (IASI) allows global coverage with very high spatial resolution and its measurements are promising for long-term ozone monitoring. In this study, Microwave Limb Sounder (MLS) O3 profiles and IASI O3 partial columns (1013.25-345 hPa) are assimilated in a chemistry transport model to produce 6-hourly analyses of tropospheric ozone for 6 years (2008-2013). We have compared and evaluated the IASI-MLS analysis and the MLS analysis to assess the added value of IASI measurements. The global chemical transport model MOCAGE (MOdèle de Chimie Atmosphérique à Grande Echelle) has been used with a linear ozone chemistry scheme and meteorological forcing fields from ERA-Interim (ECMWF global reanalysis) with a horizontal resolution of 2° × 2° and 60 vertical levels. The MLS and IASI O3 retrievals have been assimilated with a 4-D variational algorithm to constrain stratospheric and tropospheric ozone respectively. The ozone analyses are validated against ozone soundings and tropospheric column ozone (TCO) from the OMI-MLS residual method. In addition, an Ozone ENSO Index (OEI) is computed from the analysis to validate the TCO variability during the ENSO events. We show that the assimilation of IASI reproduces the variability of tropospheric ozone well during the period under study. The variability deduced from the IASI-MLS analysis and the OMI-MLS measurements are similar for the period of study. The IASI-MLS analysis can reproduce the extreme oscillation of tropospheric ozone caused by ENSO events over the tropical Pacific Ocean, although a correction is required to reduce a constant bias present in the IASI-MLS analysis.

A Multi-Wavelength Study of Parent Volatile Abundances in Comet C/2006 M4 (SWAN)

NASA Technical Reports Server (NTRS)

DiSanti, Michael A.; Villanueva, Geronimo L.; Milam, Stefanie N.; Zack, Lindsay N.; Bonev, Boncho P.; Mumma, Michael; Ziurys, Lucy M.; Anderson, William M.

2009-01-01

Volatile organic emissions were detected post-perihelion in the long period comet C/2006 M4 (SWAN) in October and November 2006. Our study combines target-of-opportunity, observations using the infrared Cryogenic Echelle Spectrometer (CSHELL) at the NASA-IRTF 3-m telescope, and millimeter wavelength observations using the Arizona Radio Observatory (ARO) 12-m telescope. Five parent volatiles were measured with CSHELL (H2O, CO, CH3OH, CH4, and C2H6), and two additional species (HCN and CS) were measured with the ARID 12-m. These revealed highly depleted CO and somewhat enriched CH3OH compared with abundances observed in the dominant group of long-period (Oort cloud) comets in our sample and similar to those observed recently in Comet 8P/Tuttle. This may indicate highly efficient H-atom addition to CO at very low temperature (approx.10-20 K) on the surfaces of interstellar (pre-cometary) grains. Comet C12006 M4 had nearly "normal" C2H6, and CH4, suggesting a processing history similar to that experienced by the dominant group. When compared with estimated water production at the time of the millimeter observations, HCN was slightly depleted compared with the normal abundance in comets based on 1R observations but was consistent with the majority of values from the millimeter. The ratio CS/HCN in C/2006 M4 was within the range measured in ten comets at millimeter wavelengths. The higher apparent H-atom conversion efficiency compared with most comets may indicate that the icy grains incorporated into C/2006 M4 were exposed to higher H-atom densities, or alternatively to similar densities but for a longer period of time.

Is the Young Star RZ Piscium Consuming Its Own (Planetary) Offspring?

NASA Astrophysics Data System (ADS)

Punzi, K. M.; Kastner, J. H.; Melis, C.; Zuckerman, B.; Pilachowski, C.; Gingerich, L.; Knapp, T.

2018-01-01

The erratically variable star RZ Piscium (RZ Psc) displays extreme optical dropout events and strikingly large excess infrared emission. To ascertain the evolutionary status of this intriguing star, we obtained observations of RZ Psc with the European Space Agency’s X-ray Multi-Mirror Mission (XMM-Newton), as well as high-resolution optical spectroscopy with the Hamilton Echelle on the Lick Shane 3 m telescope and with HIRES on the Keck I 10 m telescope. The optical spectroscopy data demonstrate that RZ Psc is a pre-main sequence star with an effective temperature of 5600 ± 75 K and log g of 4.35 ± 0.10. The ratio of X-ray to bolometric luminosity, {log}{L}X/{L}{bol}, lies in the range ‑3.7 to ‑3.2, consistent with ratios typical of young, solar-mass stars, thereby providing strong support for the young star status of RZ Psc. The Li absorption line strength of RZ Psc suggests an age in the range 30–50 Myr, which in turn implies that RZ Psc lies at a distance of ∼170 pc. Adopting this estimated distance, we find the Galactic space velocity of RZ Psc to be similar to the space velocities of stars in young moving groups near the Sun. Optical spectral features indicative of activity and/or circumstellar material are present in our spectra over multiple epochs, which provide evidence for the presence of a significant mass of circumstellar gas associated with RZ Psc. We suggest that the destruction of one or more massive orbiting bodies has recently occurred within 1 au of the star, and we are viewing the aftermath of such an event along the plane of the orbiting debris.

Qatar-2: A K Dwarf Orbited by a Transiting Hot Jupiter and a Longer-Period Massive Planet

NASA Astrophysics Data System (ADS)

Bryan, Marta; Alsubai, K. A.; Latham, D. W.; Quinn, S. N.; Collier Cameron, A.; Carter, J. A.; Buchave, L. A.

2012-01-01

We report the discovery and initial characterization of Qatar-2b, a hot Jupiter transiting a K dwarf in a circular orbit with a short period, Pb = 1.34 days. Differential photometry and model fitting of transit data from both KeplerCam and LCOGT yielded light curve parameters Rp/Rs, a/Rs, u1, u2, and i that were optimized using the Markov Chain Monte Carlo technique. Radial velocity measurements from the Tillinghast Reflector Echelle Spectrograph of Qatar-2 over a span of 153 days provided a mass estimate for Qatar-2b, with velocity residuals from the orbital solution that pointed to the presence of a third body in the system. The light curve parameter a/Rs and spectroscopic values for effective temperature and metallicity were used in conjunction with stellar models to estimate the mass and radius of Qatar-2, leading to a mass and radius for Qatar-2b of MP = 2.54 MJ and RP = 1.14 RJ, respectively. Next we used the Systemic Console to explore possible orbital solutions for the outer companion, Qatar-2c. Plausible solutions have periods slightly less than a year and a mass of several MJ. However, further observations are needed to determine a reliable orbit for Qatar-2c. Qatar-2 is only the fourth example in the short but growing list of systems with a transiting hot Jupiter and an outer companion. This system architecture is in sharp contrast to that found by Kepler for multi-transiting systems, which are dominated by objects smaller than Neptune, usually with tightly spaced orbits that must be nearly coplanar.

Immersive telepresence system using high-resolution omnidirectional movies and a locomotion interface

NASA Astrophysics Data System (ADS)

Ikeda, Sei; Sato, Tomokazu; Kanbara, Masayuki; Yokoya, Naokazu

2004-05-01

Technology that enables users to experience a remote site virtually is called telepresence. A telepresence system using real environment images is expected to be used in the field of entertainment, medicine, education and so on. This paper describes a novel telepresence system which enables users to walk through a photorealistic virtualized environment by actual walking. To realize such a system, a wide-angle high-resolution movie is projected on an immersive multi-screen display to present users the virtualized environments and a treadmill is controlled according to detected user's locomotion. In this study, we use an omnidirectional multi-camera system to acquire images real outdoor scene. The proposed system provides users with rich sense of walking in a remote site.

Supporting Uncertainty Reasoning in SIMulated Operators for Networks (SIMON) (Le support du raisonnement dans l’incertitude pour des operateurs simules dans un reseau)

DTIC Science & Technology

2005-12-01

moteur de simulation de l’Environnement Intégré de Modélisation de la Performance est utilisé de pair avec l’approche pour démontrer comment des...d’être utilisé dans les forces générées par ordinateur. Le travail ultérieur inclura plus d’essais, l’intégration avec les moteurs de simulateurs et...Aspects are reasoning units relevant to simulated tasks. Each Aspect schema is a 4-tuple: AspectSchema = <MA, WM, LM, CL>, where MA refers to meta

Calcul à la rupture en présence d'un écoulement : formulation cinématique avec un champ de pression approché

NASA Astrophysics Data System (ADS)

Corfdir, Alain

2006-03-01

We attempt here to use the kinematic method of yield design in the case of a porous medium subjected to flow (with or without free surface), without looking for the exact solution of the pressure field. The method proposed here is based on the use of approximate pressure fields. In this paper, we show how, under different conditions concerning the yield criterion and the velocity field, the use of such approximate fields allows one to obtain a necessary condition for stability without having to find the real pressure field. To cite this article: A. Corfdir, C. R. Mecanique 334 (2006).

Détection homodyne pour mémoires holographiques à stockage bit à bit

NASA Astrophysics Data System (ADS)

Maire, G.; Pauliat, G.; Roosen, G.

2006-10-01

Les mémoires holographiques à stockage bit à bit sont une alternative intéressante à l'approche holographique conventionnelle par pages de données du fait de leur architecture optique simplifiée. Nous proposons et validons ici une procédure de lecture adaptée à de telles mémoires et basée sur une détection homodyne de l'amplitude diffractée par les hologrammes. Ceci permet d'augmenter la quantité de signal utile détecté et s'avère donc prometteur pour accroître le taux de transfert de données de ces mémoires.

Binary-induced magnetic activity?. Time-series echelle spectroscopy and photometry of HD 123351 = CZ CVn

NASA Astrophysics Data System (ADS)

Strassmeier, K. G.; Carroll, T. A.; Weber, M.; Granzer, T.; Bartus, J.; Oláh, K.; Rice, J. B.

2011-11-01

Context. Multi-wavelength time-series observations with high cadence and long duration are needed to resolve and understand the many variations of magnetically active late-type stars, which is an approach often used to observe the Sun. Aims: We present a first and detailed study of the bright and active K0IV-III star HD 123351. Methods: We acquired a total of 955 high-resolution STELLA echelle spectra during the years 2006-2010 and a total of 2260 photometric VIC data points during 1998-2010. These data are complemented by some spectra from CFHT and KPNO. Results: The star is found to be a single-lined spectroscopic binary with a period of 147.8919 ± 0.0003 days and a large eccentricity of e = 0.8086 ± 0.0001. The rms of the orbital solution is just 47 m s-1, making it the most precise orbit ever obtained for an active binary system. The rotation period is constrained from long-term photometry to be 58.32 ± 0.01 days. It shows that HD 123351 is a very asynchronous rotator, rotating five times slower than the expected pseudo-synchronous value. Two spotted regions persisted throughout the 12 years of our observations. We interpret them as active longitudes on a differentially rotating surface with a ΔP/P of 0.076. Four years of Hα, Ca ii H&K and He i D3 monitoring identifies the same main periodicity as the photometry but dynamic spectra also indicate that there is an intermittent dependence on the orbital period, in particular for Ca ii H&K in 2008. Line-profile inversions of a pair of Zeeman sensitive/insensitive iron lines yield an average surface magnetic-flux density of 542 ± 72 G. The time series for 2008 is modulated by the stellar rotation as well as the orbital motion, such that the magnetic flux is generally weaker during times of periastron and that the chromospheric emissions vary in anti-phase with the magnetic flux. We also identify a broad and asymmetric lithium line profile and measure an abundance of log n(Li) = 1.70 ± 0.05. The star's position in the H-R diagram indicates a mass of 1.2 ± 0.1 M⊙ and an age of 6-7 Gyr. Conclusions: We interpret the anti-phase relation of the magnetic flux with the chromospheric emissions as evidence that there are two magnetic fields present at the same time, a localized surface magnetic field associated with spots and a global field that is oriented towards the (low-mass) secondary component. We suggest that the inter-binary field is responsible for the magnetic-flux dilution at periastron. It is also likely to be responsible for the unexpected slow and asynchronous rotation of the primary star. Based on data obtained with the STELLA robotic telescope in Tenerife, an AIP facility jointly operated by AIP and IAC, and the Potsdam Automatic Photoelectric Telescopes (APT) in Arizona, jointly operated by AIP and Fairborn Observatory.

VizieR Online Data Catalog: Radial velocities in M67. I. 1278 candidate members (Geller+, 2015)

NASA Astrophysics Data System (ADS)

Geller, A. M.; Latham, D. W.; Mathieu, R. D.

2015-10-01

This is the first in a series of papers studying the dynamical state of the old open cluster M67 through precise radial velocities. This is also the paper LXVII of the WIYN Open Cluster Study. Our radial velocity survey of M67 began as part of the dissertation work of Mathieu (1983PhDT.........8M), taking advantage of the CfA Digital Speedometers (DS). Three nearly identical instruments were used, initially on the MMT (from HJD2445337 to HJD2450830) and 1.5m Tillinghast Reflector (from HJD2444184 to HJD2454958) at the Fred Lawrence Whipple Observatory on Mount Hopins, Arizona, and then later on the 1.5m Wyeth Reflector (from HJD2445722 to HJD2453433) at the Oak Ridge Observatory in the Town of Harvard, Massachusetts. Subsequently the M67 target samples were expanded several times. Radial velocities measurements from other programs were integrated into the database, and our observational facilities were extended to include Hydra Multi-Object Spectrograph (MOS) at the WIYN Observatory (from HJD2453386 to HJD2456709) and the new Tillinghast Reflector Echelle Spectrograph (TRES) on the Tillinghast Reflector (from HJD2455143 to HJD2456801). Details about the telescopes, observing procedures, and data reductions of spectra obtained with the CfA DS can be found in Latham (1985srv..conf...21L, 1992ASPC...32..110L). The corresponding information for spectra obtained with Hydra at the WIYN Observatory can be found in Geller et al. 2008 (cat. J/AJ/135/2264), Geller et al. 2010 (cat. J/AJ/139/1383) and Hole et al. (2009). TRES is a stabilized fiber-fed echelle spectrograph with a CCD detector and resolution of 44000. The initial CfA sample was defined in 1982. The last surviving CfA Digital Speedometer, on the 1.5m Tillinghast Reflector, was retired in the summer of 2009. Over the following five observing seasons, TRES was used to continue the radial velocity observations of targets (mostly binaries) from both the CfA and the WIYN samples. Importantly, Roger Griffin and James Gunn also had a radial velocity program for M67 from 1971 to 1982 at the Palomar Hale 5m telescope (from HJD2440952 to HJD2445297), which they supplemented with contemporaneous observations obtained with the CORAVEL instrument (from HJD2444340 to HJD2446413) at Haute Provence for five of the binaries. Their target sample was very similar to our initial sample. We refer to the target stars and the measurements taken at all telescope/instrument pairs except WIYN/Hydra as the CfA sample and data. As of 2015 February, there are 447 stars in the CfA sample. WIYN observations of M67 began on 2005 January 15 as part of the WIYN Open Cluster Study (WOCS; Mathieu, 2000ASPC..198..517M). In total there are 1278 stars within the WIYN stellar sample; 382 of these stars are also in the CfA stellar sample. (1 data file).

Position-specific isotope modeling of organic micropollutants transformations through different reaction pathways

NASA Astrophysics Data System (ADS)

Jin, Biao; Rolle, Massimo

2016-04-01

Organic compounds are produced in vast quantities for industrial and agricultural use, as well as for human and animal healthcare [1]. These chemicals and their metabolites are frequently detected at trace levels in fresh water environments where they undergo degradation via different reaction pathways. Compound specific stable isotope analysis (CSIA) is a valuable tool to identify such degradation pathways in different environmental systems. Recent advances in analytical techniques have promoted the fast development and implementation of multi-element CSIA. However, quantitative frameworks to evaluate multi-element stable isotope data and incorporating mechanistic information on the degradation processes [2,3] are still lacking. In this study we propose a mechanism-based modeling approach to simultaneously evaluate concentration as well as bulk and position-specific multi-element isotope evolution during the transformation of organic micropollutants. The model explicitly simulates position-specific isotopologues for those atoms that experience isotope effects and, thereby, provides a mechanistic description of isotope fractionation occurring at different molecular positions. We validate the proposed approach with the concentration and multi-element isotope data of three selected organic micropollutants: dichlorobenzamide (BAM), isoproturon (IPU) and diclofenac (DCF). The model precisely captures the dual element isotope trends characteristic of different reaction pathways and their range of variation consistent with observed multi-element (C, N) bulk isotope fractionation. The proposed approach can also be used as a tool to explore transformation pathways in scenarios for which position-specific isotope data are not yet available. [1] Schwarzenbach, R.P., Egli, T., Hofstetter, T.B., von Gunten, U., Wehrli, B., 2010. Global Water Pollution and Human Health. Annu. Rev. Environ. Resour. doi:10.1146/annurev-environ-100809-125342. [2] Jin, B., Haderlein, S.B., Rolle, M., 2013. Integrated carbon and chlorine isotope modeling: Applications to chlorinated aliphatic hydrocarbons dechlorination. Environ. Sci. Technol. 47, 1443-1451. doi:10.1021/es304053h. [3] Jin, B., Rolle, M., 2014. Mechanistic approach to multi-element isotope modeling of organic contaminant degradation. Chemosphere 95, 131-139. doi:10.1016/j.chemosphere.2013.08.050.

Detection and Identification of Mars Analogue Volcano — Ice Interaction Environments

NASA Astrophysics Data System (ADS)

Cousins, C. R.; Crawford, I.; Gunn, M.; Harris, J. K.; Steele, A.

2012-03-01

Volcano-ice interaction produces many environments available to microbial colonisation. Similar processes are likely to have occurred on Mars, and are prime exobiology targets. Multi-instrument analyses of volcano-ice deposits are presented.

PROCESS DESIGN FOR ENVIRONMENT: A MULTI-OBJECTIVE FRAMEWORK UNDER UNCERTAINTY

EPA Science Inventory

Designing chemical processes for environment requires consideration of several indexes of environmental impact including ozone depletion and global warming potentials, human and aquatic toxicity, and photochemical oxidation, and acid rain potentials. Current methodologies like t...

A workout for virtual bodybuilders (design issues for embodiment in multi-actor virtual environments)

NASA Technical Reports Server (NTRS)

Benford, Steve; Bowers, John; Fahlen, Lennart E.; Greenhalgh, Chris; Snowdon, Dave

1994-01-01

This paper explores the issue of user embodiment within collaborative virtual environments. By user embodiment we mean the provision of users with appropriate body images so as to represent them to others and also to themselves. By collaborative virtual environments we mean multi-user virtual reality systems which support cooperative work (although we argue that the results of our exploration may also be applied to other kinds of collaborative systems). The main part of the paper identifies a list of embodiment design issues including: presence, location, identity, activity, availability, history of activity, viewpoint, action point, gesture, facial expression, voluntary versus involuntary expression, degree of presence, reflecting capabilities, manipulating the user's view of others, representation across multiple media, autonomous and distributed body parts, truthfulness and efficiency. Following this, we show how these issues are reflected in our own DIVE and MASSIVE prototype collaborative virtual environments.

Digital Topographic Mapping in Urban Obstructed Environment Based on Multi-GNSS Network RTK Technology

NASA Astrophysics Data System (ADS)

Guo, Qiuying; Zhao, Tonglong; Zhang, Chao; Wu, Xuxiang

2017-10-01

Digital topographic mapping experiments were carried out based on network RTK technology using GPS/BEIDOU/GLONASS multi-constellation compatible GNSS receivers in urban obstructed environment. Operation scheme and technique flow were discussed. Experimental results show that the horizontal position and elevation of the points measured by RTK can reach 2cm and 3cm precision level respectively in open environment. RTK initialization time needs about 3-5s. While in obstructed environment, such as high building and tree shanding, the RTK initialization time needs about dozens of seconds or tens of seconds, and sometimes floating solutions or even differential solutions were obtained. The impact of dense and tall building on RTK measurement is more seriously. It is more likely to get RTK fixed solution in the south side of high building than the north side of the building.

Conserving and Enhancing the Natural Environment: A Guide for Planning, Design, Construction, and Maintenance on New & Existing School Sites.

ERIC Educational Resources Information Center

Maryland State Dept. of Education, Baltimore. School Facilities Branch.

Natural environments on school sites provide considerable multi-disciplinary educational opportunities, many of which are "hands-on" experiences that stimulate learning. This document presents guidelines on conserving and enhancing the natural environment on school sites. It provides guidance for developing the site requirements in…

The Role of Environment Design in an Educational Multi-User Virtual Environment

ERIC Educational Resources Information Center

Papachristos, Nikiforos M.; Vrellis, Ioannis; Natsis, Antonis; Mikropoulos, Tassos A.

2014-01-01

This paper presents empirical results from an exploratory study conducted in an authentic educational situation with preservice education students enrolled in an undergraduate course, which was partially taught in Second Life. The study investigated the effect of environment design on presence, learning outcomes and the overall experience of the…

Concepts for a NASA Applied Spaceflight Environments Office

NASA Technical Reports Server (NTRS)

Edwards, David L.; Burns, Howard D.; Xapsos, Michael; Spann, Jim; Suggs, Robert

2010-01-01

The National Aeronautics and Space Administration (NASA) is launching a bold and ambitious new space initiative. A significant part of this new initiative includes exploration of new worlds, the development of more innovative technologies, and expansion our presence in the solar system. A common theme to this initiative is the exploration of space beyond Low Earth Orbit (LEO). As currently organized, NASA does not have an Agency-level office that provides coordination of space environment research and development. This has contributed to the formation of a gap between spaceflight environments knowledge and the application of this knowledge for multi-program use. This paper outlines a concept to establish a NASA-level Applied Spaceflight Environments (ASE) office that will provide coordination and funding for sustained multi-program support in three technical areas that have demonstrated these needs through customer requests. These technical areas are natural environments characterization and modeling, materials and systems analysis and test, and operational space environments modeling and prediction. This paper will establish the need for the ASE, discuss a concept for organizational structure and outline the scope in the three technical areas

A Bayesian Poisson-lognormal Model for Count Data for Multiple-Trait Multiple-Environment Genomic-Enabled Prediction.

PubMed

Montesinos-López, Osval A; Montesinos-López, Abelardo; Crossa, José; Toledo, Fernando H; Montesinos-López, José C; Singh, Pawan; Juliana, Philomin; Salinas-Ruiz, Josafhat

2017-05-05

When a plant scientist wishes to make genomic-enabled predictions of multiple traits measured in multiple individuals in multiple environments, the most common strategy for performing the analysis is to use a single trait at a time taking into account genotype × environment interaction (G × E), because there is a lack of comprehensive models that simultaneously take into account the correlated counting traits and G × E. For this reason, in this study we propose a multiple-trait and multiple-environment model for count data. The proposed model was developed under the Bayesian paradigm for which we developed a Markov Chain Monte Carlo (MCMC) with noninformative priors. This allows obtaining all required full conditional distributions of the parameters leading to an exact Gibbs sampler for the posterior distribution. Our model was tested with simulated data and a real data set. Results show that the proposed multi-trait, multi-environment model is an attractive alternative for modeling multiple count traits measured in multiple environments. Copyright © 2017 Montesinos-López et al.

Development of multi-year land cover data to assess wildfire impacts to coastal watersheds and the nearshore environment

NASA Astrophysics Data System (ADS)

Morrison, Katherine D.

In the Mediterranean ecosystems of coastal California, wildfire is a common disturbance that can significantly alter vegetation in watersheds that transport sediment and nutrients to the adjacent nearshore oceanic environment. We assess the impact of two wildfires that burned in 2008 on land cover and to the nearshore environment along the Big Sur coast in central California. We created a multi-year land cover dataset to assess changes to coastal watersheds as a result of fire. This land cover dataset was then used to model changes in nonpoint source pollutants transported to the nearshore environment. Results indicate post-fire increases in percent export compared to pre-fire years and also link wildfire severity to the specific land cover changes that subsequently increase exports of pollutants and sediment to the nearshore environment. This approach is a replicable across watersheds and also provides a framework for including the nearshore environment as a value at risk terrestrial land management revolving around wildfire, including suppression, thinning, and other activities that change land cover at a landscape scale.