• NEANIAS Space Research Community

Active regions (ARs) are typical magnetic structures found in the solar atmosphere. We calculate several magnetohydrostatic (MHS) equilibrium models that include the effect of a finite plasma-$\beta$ and gravity and that are representative of these structures in three dimensions. The construction of the models is based on the use of two Euler potentials, $\alpha$ and $\beta$, that represent the magnetic field as ${\bf B}=\nabla \alpha \times \nabla \beta$. The ideal MHS nonlinear partial differential equations are solved numerically using finite elements in a fixed 3D rectangular domain. The boundary conditions are initially chosen to correspond to a potential magnetic field (current-free) with known analytical expressions for the corresponding Euler potentials. The distinctive feature is that we incorporate the effect of shear by progressively deforming the initial potential magnetic field. This procedure is quite generic and allows us to generate a vast variety of MHS models. The thermal structure of the ARs is incorporated through the dependence of gas pressure and temperature on the Euler potentials. Using this method we achieve the characteristic hot and over-dense plasma found in ARs, but we demonstrate that the method can also be applied to study configurations with open magnetic field lines. Furthermore, we investigate basic topologies that include neutral lines. Our focus is on the force balance of the structures and we do not consider the energy balance in the constructed models. In addition, we address the difficult question of the stability of the calculated 3D models. We find that if the plasma is convectively stable, then the system is not prone in general to develop magnetic Rayleigh-Taylor instabilities. Comment: Accepted for publication in A&A

EBEX is a NASA-funded balloon-borne experiment designed to measure the polarization of the cosmic microwave background (CMB). Observations will be made using 1432 transition edge sensor (TES) bolometric detectors read out with frequency multiplexed SQuIDs. EBEX will observe in three frequency bands centered at 150, 250, and 410 GHz, with 768, 384, and 280 detectors in each band, respectively. This broad frequency coverage is designed to provide valuable information about polarized foreground signals from dust. The polarized sky signals will be modulated with an achromatic half wave plate (AHWP) rotating on a superconducting magnetic bearing (SMB) and analyzed with a fixed wire grid polarizer. EBEX will observe a patch covering ~1% of the sky with 8' resolution, allowing for observation of the angular power spectrum from \ell = 20 to 1000. This will allow EBEX to search for both the primordial B-mode signal predicted by inflation and the anticipated lensing B-mode signal. Calculations to predict EBEX constraints on r using expected noise levels show that, for a likelihood centered around zero and with negligible foregrounds, 99% of the area falls below r = 0.035. This value increases by a factor of 1.6 after a process of foreground subtraction. This estimate does not include systematic uncertainties. An engineering flight was launched in June, 2009, from Ft. Sumner, NM, and the long duration science flight in Antarctica is planned for 2011. These proceedings describe the EBEX instrument and the North American engineering flight. 12 pages, 9 figures, Conference proceedings for SPIE Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy V (2010)

Abstract We report the detection of benzene ( c -C 6 H 6 ) in the upper atmospheres of Jupiter at midlatitudes and Saturn (disk average). Observations with the Short-Wavelength Spectrometer of the Infrared Space Observatory reveal emission from the Q -branch of benzene around 14.84 μm on these two planets but not on Uranus and Neptune. Column densities have been derived through radiative transfer calculations assuming various mixing ratio profiles. The inferred abundances are 9 +4.5 −7.5 ×10 14 molecules cm −2 above the 50-mbar level on Jupiter and 4.7 +2.1 −1.1 ×10 13 molecules cm −2 above the 10-mbar level on Saturn. Upper limits have been derived for Uranus and Neptune. Results are compared with existing chemical models.

Extreme Ultraviolet Explorer satellite observations of Jupiter's Io plasma torus conducted over a two-year time period before, during and after the impacts of comet Shoemaker-Levy/9 reveal that no new spectral features appeared in the 400–715 A spectral region. Io torus emission line luminosities remained stable to within ±20% and showed no strong coherent increasing or decreasing trend during the weeks preceding or following the impact events. This work supersedes our previous claims of possible luminosity changes to the torus derived from the same data (McGrath et al., Science, 267, 1313, 1995)

Dense gas clouds containing OH, CO, NH3 and H2CO are found in the inner part of the Hi nuclear disk. The molecular spectral lines allow direct observations of the kinematics of the gas near the galactic centre. Strong absorption of the thermal continuum sources by OH and H2CO shows that much of the gas on the near side of the centre can be located in a massive ‘ring’ expanding at 130 km s -1 which may have originated close to the nucleus about 106 yr ago. Observations of CO emission from beyond the centre show that the far side of the ‘ring’ is expanding at a lower velocity, less than 90 km s-1. Observations of CO and NH3 emission with positive velocities for l< 360° are needed to establish whether the ‘ring’ is a continuous structure.

The visual location accuracy of assembly robot is affected directly by the accuracy of image segmentation. Most traditional algorithms couldn’t meet the industrial manufacture rhythm of Printed Circuit Board Assembly (PCBA) components. As a result, this paper proposed a novel superpixels image segmentation algorithm for PCBA components. Firstly, the salient feature was extracted by Histogram-based Contrast (HC) algorithm. Then, the salience map was extracted according to the Simple Non-Iterative Clustering (SNIC) superpixels segmentation algorithm. A new method was proposed to obtain information entropy by creating a new superpixels image. Ultimately, the segmented image was obtained according to the information entropy. According to the experimental results, the F-measure, the MAE and the time were 0.7979, 0.040567 and 179.12851s respectively, showing that the proposed algorithm was better than the other six algorithms.

Aims. The main purpose of our investigation is to construct the long-time light curve of the PMS star V 1184 Tau. We consider the study of the photometrical variability of PMS stars as very important for understanding stellar evolution. The unusual photometric variability of V 1184 Tau was reported in previous studies as well, but the nature of the observed deep minima is still under discussion. Methods. We present recent data from CCD photometry and from archival photographic plates. The photometric BVRI data presented in this paper were collected from November 2005 to November 2007. To construct the historical light curve of V 1184 Tau, a search for archived photographic observations in the Wide-Field Plate Database (WFPDB) was made. As a result, 412 photographic plates were found containing the field of V 1184 Tau. A part of the plates were scanned at our request and a magnitude estimation was made of V 1184 Tau. Results. Our recent photometric data suggest that the star brightness is still near the minimum. Thus the period of strong light variations that started in 2003 continues up to the present, hence more than 4 years. Our data from the archival photographic plates suggest that an unknown minimum of brightness exists in the approximate period 1980-1985. Taking all available photometric and spectroscopic data into account we must reject the hypothesis that V 1184 Tau is an FU Orionis type object. V 1184 Tau is a G type low-mass star whose spectrum is similar to WTT stars, but its photometric behavior is typical of the UX Orionis variable stars. Assuming the obscuration from orbiting dust clouds as a reason for a deep minimum, we estimate the approximate period of obscurations and the interval between two deep minima. Our calculations give a 25-28 year period between the two minima and approximately 8-10 year duration of the minima.

En este artículo presentamos la investigación que desarrollamos desde hace dos años trabajando con recursos y herramientas tic para enseñar a las personas mayores su uso, funcionalidades y beneficios que les pueden aportar. Consideramos que en la sociedad actual no hemos dado una respuesta satisfactoria a la formación de este colectivo de personas mayores que pensamos que está desfavorecido y lo estamos considerando una necesidad ante los constantes avances y cambios referidos a las tecnologías. Las herramientas que hemos incorporado son la pizarra digital y tabletas para navegación por internet y uso de algunas aplicaciones relacionadas con los dispositivos Android y referidas al dibujo y las mejoras cognitivas; robots básicos para iniciar la programación, la implicación emocional y el pensamiento lógico, y gafas de realidad virtual para acercar la novedad inmersiva en el conocimiento o recuerdo de diferentes entornos. Los buenos resultados obtenidos en este periodo nos animan a continuar y consolidar el proyecto de investigación y definir los modelos didácticos más adecuados y las competencias básicas digitales pertinentes. In this article, we present the research we have been developing for the last two years, working with ict resources and tools to teach older people about its use, functionalities and benefits that can be provided to them. We believe that in today’s society we have not given a satisfactory response to the formation of this group of older people that we think is disadvantaged in terms of the use of ict training and we are considering it a necessity in the face of constant advances and changes related to technologies. The tools we have incorporated are the digital board and tablets for Internet browsing and use of some applications related to Android devices and referred to drawing and cognitive improvements, basic robots to start programming, emotional involvement and logical thinking and glasses of virtual reality to bring the immersive novelty in the knowledge or memory of different environments.The good results obtained in this period encourage us to continue and consolidate the research project and define the most appropriate didactic models and the relevant digital basic competences.

International audience; During sensemaking, people annotate insights: underlining sentences in a document or circling regions on a map. They jot down their hypotheses: drawing correlation lines on scatterplots or creating personal legends to track patterns. We present ActiveInk, a system enabling people to seamlessly transition between exploring data and externalizing their thoughts using pen and touch. ActiveInk enables the natural use of pen for active reading behaviors, while supporting analytic actions by activating any of these ink strokes. Through a qualitative study with eight participants, we contribute observations of active reading behaviors during data exploration and design principles to support sensemaking.